Patent Publication Number: US-2023148814-A1

Title: Surface cleaning apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is:
         (a) a continuation-in-part of U.S. Patent Application Ser. No. 16/818,438, filed on Mar. 31, 2020, which is allowed, which itself claims priority from co-pending United States Provisional Patent Application No. 62/818,856, filed on Mar. 15, 2019, and also claims priority from U.S. patent application Ser. No. 62/1825,148, filed on Mar. 28, 2019;   (b) a continuation-in-part of U.S. patent application Ser. No. 17/458,217 which was filed on Aug. 26, 2021, which itself is continuation-in-part of U.S. patent application Ser. No. 17/342,410, filed on Jun. 8, 2021, which itself is a continuation of:
           a. U.S. patent Application Ser. No. 16/822,708, filed on Mar. 18, 2020;   b. U.S. patent application Ser. No. 16/823,191 filed on Mar. 18, 2020;   c. U.S. patent application Ser. No. 16/823,203, filed on Mar. 18, 2020; and,   d. U.S. patent application Ser. No. 16/823,216, filed on Mar. 18, 2020 and issued as U.S. Pat. No. 11/445,878 on Sep. 20, 2022;   
           (c) a continuation-in-part of U.S. patent application Ser. No. 17/342299 which was filed on Jun. 8, 2021, which itself is a continuation of U.S. patent application Ser. No. 16/900,465, filed on Jun. 12, 2020 and issued as U.S. Pat. No. 11,445,875 on Sep. 20, 2020, which itself is a continuation of U.S. patent application Ser. No. 15/642,781, filed Jul. 6, 2017, and issued as U.S. Pat. No. 10,722,086 on Jul. 28, 2020; and,   (d) a continuation-in-part of U.S. patent application Ser. No. 17/694,362 which was filed on Mar. 14, 2022, which itself is a continuation-in-part of U.S. patent application Ser. No. 17/471.041, filed on Sep. 9, 2021, which is a continuation of U.S. patent application Ser. No. 16/806,726, filed on Mar. 2, 2020, and issued as U.S. Pat. No. 11,219,906 on Jan. 11, 2022, which itself is a continuation-in-part of U.S. patent application Ser. No. 16/447,308, filed on Jun. 20, 2019 and issued as U.S. Pat. No. 10,966,583 on Apr. 6, 2021, which itself is a continuation-in-part of U.S. patent application Ser. No. 16/254,918, filed on Jan. 23, 2019 and issued as U.S. Pat. No. 10,828,649 on Nov. 10, 2020.       

     the entirety of each of which is incorporated herein by reference in its entirety. 
    
    
     FIELD 
     This disclosure relates generally to surface cleaning apparatus such as hand vacuum cleaners, upright vacuum cleaners, stick vacuum cleaners or canister vacuum cleaners, and, in particular, portable surface cleaning apparatus, such as hand vacuum cleaners. 
     INTRODUCTION 
     The following is not an admission that anything discussed below is part of the prior art or part of the common general knowledge of a person skilled in the art. 
     Various types of surface cleaning apparatus are known, including upright surface cleaning apparatus, canister surface cleaning apparatus, stick surface cleaning apparatus, central vacuum systems, and hand carriable surface cleaning apparatus such as hand vacuum cleaners. Further, various designs for cyclonic surface cleaning apparatus, including battery operated cyclonic hand vacuum cleaners are known in the art. 
     SUMMARY 
     The following introduction is provided to introduce the reader to the more detailed discussion to follow. The introduction is not intended to limit or define any claimed or as yet unclaimed invention. One or more inventions may reside in any combination or sub-combination of the elements or process steps disclosed in any part of this document including its claims and figures. 
     In accordance with an aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, a surface cleaning apparatus includes an air treatment assembly. A rib extends into a chamber of the assembly from a wall of the chamber, which may be a cyclone. The rib interrupts air flow, which may be cyclonic air flow, and encourages dirt accumulation adjacent the rib. The rib may be at one of the ends of the chamber, and optionally at an end at which an air outlet of the chamber is located. The rib may extend inwardly into the air treatment chamber from the air treatment chamber end wall (e.g., the outlet end wall). The rib may extend radially into the air treatment chamber from an air treatment chamber sidewall (e.g., radially inwardly) and/or axially from the air treatment chamber end wall. The air treatment chamber air outlet may comprise an air permeable portion through which the air flow path extends. The outlet may also include an air impermeable portion. The air permeable portion may be a porous portion comprising a porous material that extends inwardly from the air impermeable portion. The rib may extend co-extensively (i.e., with respect to a cyclone axis) along at least a portion of the cyclone chamber in which the impermeable portion of the outlet is provided. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, the air treatment inlet conduit extends into the air treatment chamber from an upstream opening to a downstream opening. The downstream opening may be a tangential opening into the chamber when the chamber is a cyclone chamber. The inlet may include an air permeable section (e.g., covered by porous material such as a mesh) that is discrete from the downstream opening of the inlet conduit. The bulk of air is directed through the downstream opening, which may be referred to as the primary opening. A lesser volume of air is allowed to pass through the air permeable section from the air treatment inlet conduit into the air treatment chamber. The downstream opening and the air permeable section provide alternate air exits which concurrently permit air flow therethrough. The air permeable section forms a secondary pathway between the air treatment inlet conduit and the air treatment chamber. This secondary pathway results in a reduction of the power required for the motor to produce a given air flow rate. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, the axial length of the downstream opening of the inlet conduit is variable. The axial length of the downstream opening may be varied to change the separation characteristics of the surface cleaning apparatus, such as to change backpressure or to change the ratio between an effective air inlet axial length and the chamber axial length. The ratio between the effective air inlet axial length and the chamber axial length affects the number of turns that air passing through the cyclone chamber is subject to, and so affects the efficiency of the surface cleaning apparatus. The axial length may be changed manually by a user or automatically, e.g., in response to, e.g., detecting that finer particles are being collected or that particles are making past the air treatment assembly of the surface cleaning apparatus. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, the air treatment inlet is selectively closeable by a closure member. When the closure member is in the open position, during operation of the surface cleaning apparatus, air flows through the air treatment inlet to the air treatment chamber. When the closure member is in the closed position, air flow through the air treatment inlet is inhibited. The closure member may be curved along at least one dimension with respect to a coordinate system defined by the apparatus longitudinal axis, the apparatus vertical axis, and the apparatus tangential axis. The closure member may therefore be referred to as a curved member. Optionally, the closure member is curved with respect only to a single dimension, as exemplified. In other words, the closure member may be arcuate in shape. The closure member may pivot about a closure axis of rotation between an open position and a closed position. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, the closure member moves axially with respect to the air treatment member longitudinal axis and/or the inlet conduit axis. The closure member may be an end wall of the air treatment inlet. The inlet end wall may extend transverse to the flow direction. The inlet end wall may include a generally planar inlet end wall upstream face, which may extend generally perpendicular to the flow direction. Alternatively, the closure member may close a tangential inlet to the air treatment chamber. The closure member may be received against a sidewall of the air treatment inlet and translate axially to close the tangential inlet. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, the air treatment assembly has an assembly free volume that includes the chamber free volume within the chamber and an inlet free volume within the air treatment inlet. The chamber free volume is an open space within the air treatment chamber outside the air treatment inlet and the air treatment outlet. The inlet free volume is an open space within the air treatment inlet that would be included in the air flow path if the closure member was not included in the surface cleaning apparatus. The closure member in the open position may be at least partially removed from the assembly free volume. The closure member in the open position may be fully removed from the assembly free volume. This aspect reduces the extent to which the closure member inhibits air flow when in the open position and/or reduces turbulence caused by a significant discontinuity in the transverse cross sectional area of the air treatment inlet at a downstream edge of the closure member when the closure member is in the open position. The closure member is moveable between the open and closed positions, and, when in the open position may be at least partially received in a closure recess or partially moved into or through a closure passage. The recess may have a mouth or port through which it is open to the assembly free volume, and the closure member may close the port when the closure member is in the open position. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, the surface cleaning apparatus includes a driving member drivingly connected to the closure member. The closure member may move in a first direction from the open position to the closed position. The closure member may move in a second direction from the closed position to the open position. The driving member may be operable to move the closure member in at least one of the first and second directions. The driving member may be any suitable driving member. The driving member may include a closure member actuator, such as an electromechanical actuator. The driving member may include a manually moveable member. The driving member may include a suction-powered piston. The driving member may include an external conduit (e.g., a removable wand) removably insertable into the surface cleaning apparatus. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, at least a portion of a first end of the chamber is moveable between a closed operating position and an open position. The chamber first end may include the evacuation opening, and the evacuation opening may be closed when the moveable portion of the chamber first end is in the closed operating position and open when the moveable portion of the chamber first end is in the open position. The moveable portion may be rotationally moveable, translationally moveable, or inflatable and deflatable. A docking station may be operable to move the moveable portion of the chamber first end between the closed operating position and the open position. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, at least a portion of an end of the air treatment chamber is translatable generally parallel to the chamber longitudinal axis. The axially moveable end portion is moveable between a first position and a second position that is axially spaced from the first position. The second position may be forward of the first position. The axially moveable end portion may act as a plunger, e.g., to move debris through the chamber. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, opening at least a portion of the chamber first end moves at least a portion of the chamber second end. The at least a portion of the chamber second end that moves in response to opening the at least a portion of the chamber first end may be joined thereto by a linking member. The at least a portion of the chamber second end that moves in response to opening the at least a portion of the chamber first end may be an axially moveable second end portion. The at least a portion of the chamber first end may be an axially moveable first end portion. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, a fluid driven moveable member of the surface cleaning apparatus is moveable via fluid pressure through the surface cleaning apparatus, and is moveable via the fluid pressure between a first position and a second position. It will be appreciated that the fluid pressure may be air pressure (i.e., suction) generated by an air moving member of the surface cleaning apparatus or docking station. The fluid driven moveable member may be received in the apparatus air flow path and/or the evacuation air flow path. The fluid driven moveable member may include or consist of the chamber first end or a moveable portion thereof. The fluid driven moveable member may include or consist of he chamber second end or a moveable portion thereof. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, a user interface is provided at an upper end of a pistol grip handle. This location provides the user interface at a convenient location for a user of the interface. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, the user interface overlies the main body housing. The main body housing may contain the suction motor. The user interface may overly the suction motor housing. The user interface may be separated such that the user interface is not attached to the suction motor housing. The user interface may be spaced from the main body housing, and may be spaced from the main body housing by a separation air gap. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, the surface cleaning apparatus includes an annular portion. The user interface may be provided on the annular portion. The user interface may be secured to the annular portion. Optionally, the annular portion is part of the apparatus rear end. The user interface may be curved to follow an annular surface of the annular portion. The user interface may include an information display having a display surface that faces radially outward. The user interface may also, or alternatively, include an information display having a display surface that faces rearwardly. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, the surface cleaning apparatus includes a filter that is removeable from an installed position to a removed position outside the main body housing. The filter is moveable between the installed and removed positions along a removal path. The removal path may extend past the user interface between the installed position and the removed position. The removal path may extend through the user interface. The filter may be, e.g., the post-motor filter. The post-motor filter may remove rearwardly though an annular user interface body. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, a filter is removable radially outwardly with respect to the apparatus longitudinal axis. The filter may be removeable in a direction that is generally perpendicular to the apparatus longitudinal axis. The filter is removeable between an installed position and a removed position, and is removeable along a removal path. The removal path may be a radially extending path, as exemplified. The removal path may be a laterally extending path. The removal path may be generally horizontal when the apparatus upper end is above the apparatus lower end, and may be generally parallel to the apparatus transverse axis. The surface cleaning apparatus may include a plurality of radially removable filters. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects a filter is at least partially nested within the air treatment outlet. Nesting the filter may allow the surface cleaning apparatus to have a shorter axial length. The filter at least partially nested withing the air treatment outlet may be the pre-motor filter. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, the surface cleaning apparatus includes an ultraviolet light source. The ultraviolet light source is operable to generate ultraviolet light. The ultraviolet light may be used to disinfect an interior or external surface of the surface cleaning apparatus (e.g., a handle external surface or an internal surface facing the air flow path). The ultraviolet light source may be arranged to direct the ultraviolet light into a light carrying structure (such as a light pipe). The apparatus may include at least one wall that is transparent to ultraviolet light. 
     In accordance with another aspect of this disclosure, which may be used alone or in combination with any one or more other aspects, the surface cleaning apparatus may include a dirt scoop. The dirt scoop is moveable between an operational position and an evacuation position. In the operational position, the dirt scoop extends into the air treatment chamber. As it moves to the evacuation position, the dirt scoop sweeps through the chamber to dislodge debris. 
     It will be appreciated by a person skilled in the art that an apparatus or method disclosed herein may embody any one or more of the features contained herein and that the features may be used in any particular combination or sub-combination. 
     These and other aspects and features of various embodiments will be described in greater detail below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a better understanding of the described embodiments and to show more clearly how they may be carried into effect, reference will now be made, by way of example, to the accompanying drawings in which: 
         FIG.  1    is perspective view of a surface cleaning apparatus, according to an embodiment; 
         FIG.  2    is an exploded perspective view of the surface cleaning apparatus of  FIG.  1   ; 
         FIG.  3    is a rear perspective view of an embodiment of a stick vacuum cleaner incorporating the surface cleaning apparatus of  FIG.  1    in an upright storage position; 
         FIG.  4    is a rear perspective view of the stick vacuum cleaner of  FIG.  3    in a reclined cleaning position; 
         FIG.  5    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  1   ; 
         FIG.  6    is an enlarged axial cross sectional view of a portion of the surface cleaning apparatus of  FIG.  1   ; 
         FIG.  7    is a transverse cross sectional view of another embodiment of a surface cleaning apparatus, with a closure member in an open position; 
         FIG.  8    is a transverse cross sectional view of the surface cleaning apparatus of  FIG.  7   , with the closure member in a closed position; 
         FIG.  9    is an axial cross sectional view of another embodiment of a surface cleaning apparatus, with a closure member in an open position; 
         FIG.  10    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  9   , with the closure member in a closed position; 
         FIG.  11    is a transverse cross sectional view of another portion of the surface cleaning apparatus of  FIG.  1   ; 
         FIG.  12    is another axial cross sectional view of the surface cleaning apparatus of  FIG.  1   ; 
         FIG.  13    is an enlarged axial cross sectional view of another portion of the surface cleaning apparatus of  FIG.  1   ; 
         FIG.  14    is a transverse cross sectional view of another portion of the surface cleaning apparatus of  FIG.  1   ; 
         FIG.  15    is another axial cross sectional view of the surface cleaning apparatus of  FIG.  1   ; 
         FIG.  16    is an enlarged axial cross sectional view of another portion of the surface cleaning apparatus of  FIG.  1   ; 
         FIG.  17    is a perspective view of n end of an embodiment of an external onduit, such as a rigid wand; 
         FIG.  18    is a perspective view of another embodiment of an external conduit; 
         FIG.  19    is a perspective view of another embodiment of an external conduit; 
         FIG.  20    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  1    having received therein the external conduit of  FIG.  19   ; 
         FIG.  21    is a perspective view of another embodiment of an external conduit; 
         FIG.  22    is an axial cross sectional view of another embodiment of a surface cleaning apparatus having received therein the external conduit of  FIG.  21   , with a moveable inlet member in a first position; 
         FIG.  23    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  22   , with the moveable inlet member in a second position; 
         FIG.  24    is an axial cross sectional view of another embodiment of a surface cleaning apparatus, with a moveable inlet member in a first position; 
         FIG.  25    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  24   , with the moveable inlet member in a second position; 
         FIG.  26    is an enlarged axial cross sectional view of a portion of the surface cleaning apparatus of  FIG.  24   , with the moveable inlet member in the second position: 
         FIG.  27    is an axial cross sectional view of another embodiment of a surface cleaning apparatus, with a moveable inlet member in a first position; 
         FIG.  28    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  27   , with the moveable inlet member in a second position; 
         FIG.  29    is an axial cross sectional view of another embodiment of a surface cleaning apparatus, with a moveable inlet member in a first position; 
         FIG.  30    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  29   , with the moveable inlet member in a second position; 
         FIG.  31    is an axial cross sectional view of a portion of another embodiment of a surface cleaning apparatus, with a closure member in a first position; 
         FIG.  32    is an axial cross sectional view of the portion of the surface cleaning apparatus of  FIG.  31   , with the closure member in a second position; 
         FIG.  33    is a transverse cross sectional view of an inlet of the surface cleaning apparatus of  FIG.  31   ; 
         FIG.  34    is an axial cross sectional view of another embodiment of a surface cleaning apparatus, with a closure member in a first position; 
         FIG.  35    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  34   , with the closure member in a second position; 
         FIG.  36    is an axial cross sectional view of another embodiment of a surface cleaning apparatus, with a closure member in a first position; 
         FIG.  37    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  36   , with the closure member in a second position; 
         FIG.  38    is an axial cross sectional view of another embodiment of a surface cleaning apparatus, with a closure member in a first position; 
         FIG.  39    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  38   , with the closure member in a second position; 
         FIG.  40    is an axial cross sectional view of another embodiment of a surface cleaning apparatus, with a closure member in a first position; 
         FIG.  41    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  40   , with the closure member in a second position 
         FIG.  42    is a transverse cross sectional view of a portion of another embodiment of a surface cleaning apparatus, with a closure member in a first position; 
         FIG.  43    is a transverse cross sectional view of the portion of the surface cleaning apparatus of  FIG.  42   , with the closure member in a second position; 
         FIG.  44    is an axial cross sectional view of a portion of another embodiment of a surface cleaning apparatus, with a closure member in a first position: 
         FIG.  45    is an axial cross sectional view of the portion of the surface cleaning apparatus of  FIG.  44   , with the closure member in a second position; 
         FIG.  46    is a perspective view of another embodiment of a surface cleaning apparatus; 
         FIG.  47    is an exploded view of the surface cleaning apparatus of  FIG.  46   ; 
         FIG.  48    is a front perspective view of the surface cleaning apparatus of  FIG.  46    docked at a docking station; 
         FIG.  49    is an axial cross sectional view of he surface cleaning apparatus of  FIG.  46    docked at the docking station; 
         FIG.  50    is an expanded axial cross sectional view of a portion of the surface cleaning apparatus of  FIG.  46    docked at the docking station; 
         FIG.  51    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  46    with a closure member in a first position; 
         FIG.  52    is an axial cross sectional view of the surface cleaning apparatus of  FIG.  46    with the closure member in a second position; 
         FIG.  53    is an enlarged axial cross sectional view of another portion of the surface cleaning apparatus of  FIG.  46    with the closure member in the first position; 
         FIG.  54    is an enlarged axial cross sectional view of the other portion of the surface cleaning apparatus of  FIG.  46    with the closure member in the second position; 
         FIG.  55    is a schematic cross sectional view of another embodiment of a surface cleaning apparatus, with a chamber first end in a first position and a chamber second end in a first position; 
         FIG.  56    is a schematic cross sectional view of the surface cleaning apparatus of  FIG.  55   , with the chamber first end in a second position; 
         FIG.  57    is a schematic cross sectional view of the surface cleaning apparatus of  FIG.  55   , with a chamber second end in a second position; 
         FIG.  58    is a schematic cross sectional view of the surface cleaning apparatus of  FIG.  55   , with a chamber second end in a third position; 
         FIG.  59    is a schematic cross sectional view of another embodiment of a surface cleaning apparatus, with a chamber first end in a first position and a chamber second end in a first position; 
         FIG.  60    is a schematic cross sectional view of the surface cleaning apparatus of  FIG.  59   , with the chamber first end in a second position and the chamber second end in a second position; 
         FIG.  61    is a schematic cross sectional view of the surface cleaning apparatus of  FIG.  59   , with the chamber first end in a third position and the chamber second end in a third position; 
         FIG.  62    is a front perspective view of another embodiment of a surface cleaning apparatus; 
         FIG.  63    is a rear perspective view of the surface cleaning apparatus of  FIG.  62   ; 
         FIG.  64    is a front perspective axial cross sectional view of the surface cleaning apparatus of  FIG.  62   ; 
         FIG.  65    is a rear perspective axial cross sectional view of the surface cleaning apparatus of  FIG.  62   ; 
         FIG.  66    is another rear perspective view of the surface cleaning apparatus of  FIG.  62   ; 
         FIG.  67    is a perspective view of the surface cleaning apparatus of  FIG.  62    docked at a docking station; 
         FIG.  68    is an axial cross sectional view of he surface cleaning apparatus of  FIG.  62    docked at the docking station; 
         FIG.  69    is an enlarged axial cross sectional view of a portion of the surface cleaning apparatus of  FIG.  62   ; 
         FIG.  70    is an exploded view of the surface cleaning apparatus of  FIG.  62   ; 
         FIG.  71    is a rear perspective view of another embodiment of a surface cleaning apparatus, with a filter in a first position; 
         FIG.  72    is a rear perspective view of the surface cleaning apparatus of  FIG.  71   , with the filter in a second position; 
         FIG.  73    is a schematic rear cross sectional view of another embodiment of a surface cleaning apparatus, with a filter in a first position; 
         FIG.  74    is a schematic rear cross sectional view of the surface cleaning apparatus of  FIG.  73   , with the filter in a second position; 
         FIG.  75    is a schematic cross sectional view of another embodiment of a surface cleaning apparatus, with a dirt scoop in a first position; and, 
         FIG.  76    is a schematic cross sectional view of the surface cleaning apparatus of  FIG.  75   , with the dirt scoop in a second position. 
     
    
    
     The drawings included herewith are for illustrating various examples of articles methods, and apparatuses of the teaching of the present specification and are not intended to limit the scope of what is taught in any way. 
     DESCRIPTION OF EXAMPLE EMBODIMENTS 
     Various apparatuses, methods and compositions are described below to provide an example of an embodiment of each claimed invention. No embodiment described below limits any claimed invention and any claimed invention may cover apparatuses and methods that differ from those described below. The claimed inventions are not limited to apparatuses, methods and compositions having all of the features of any one apparatus, method or composition described below or to features common to multiple or all of the apparatuses, methods or compositions described below. It is possible that an apparatus, method or composition described below is not an embodiment of any claimed invention. Any invention disclosed in an apparatus, method or composition described below that is not claimed in this document may be the subject matter of another protective instrument, for example, a continuing patent application, and the applicant(s), inventor(s) and/or owner(s) do not intend to abandon, disclaim, or dedicate to the public any such invention by its disclosure in this document. 
     The terms “an embodiment,” “embodiment,” “embodiments,” “the embodiment,” “the embodiments,” “one or more embodiments,” “some embodiments,” and “one embodiment” mean “one or more (but not all) embodiments of the present invention(s),” unless expressly specified otherwise. 
     The terms “including,” “comprising” and variations thereof mean “including but not limited to,” unless expressly specified otherwise. A listing of items does not imply that any or all of the items are mutually exclusive, unless expressly specified otherwise. The terms “a,” “an” and “the” mean “one or more,” unless expressly specified otherwise. 
     As used herein and in the claims, two or more parts are said to be “coupled”, “connected”, “attached”, or “fastened” where the parts are joined or operate together either directly or indirectly (i.e., through one or more intermediate parts), so long as a link occurs. As used herein and in the claims, two or more parts are said to be “directly coupled”, “directly connected”, “directly attached”, or “directly fastened” where the parts are connected in physical contact with each other. None of the terms “coupled”, “connected”, “attached”, and “fastened” distinguish the manner in which two or more parts are joined together. 
     Furthermore, it will be appreciated that for simplicity and clarity of illustration, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the example embodiments described herein. However, it will be understood by those of ordinary skill in the art that the example embodiments described herein may be practiced without these specific details. In other instances, well-known methods, procedures, and components have not been described in detail so as not to obscure the example embodiments described herein. Also, the description is not to be considered as limiting the scope of the example embodiments described herein. 
     General Description of a Surface Cleaning Apparatus 
     Referring to  FIGS.  1  and  2   , an exemplary embodiment of a surface cleaning apparatus is shown generally as  100 . The surface cleaning apparatus is exemplified as a hand vacuum cleaner with an apparatus front end  102 , an apparatus rear end  104 , an apparatus upper end  106  and an apparatus lower end  108 . An apparatus longitudinal axis  110  extends between the apparatus front end  102  and the apparatus rear end  104 . An apparatus vertical axis  112  extends between the apparatus upper end  106  and apparatus lower end  108 . The apparatus vertical axis  112  is perpendicular to the apparatus longitudinal axis  110 . An apparatus transverse axis  114  is perpendicular to each of the apparatus vertical axis  112  and the apparatus longitudinal axis  110 . 
     The surface cleaning apparatus  100  includes a main body  120 . The main body  120  includes a main body housing  122  and a handle  124 . 
     As exemplified, the handle  124  may be a pistol grip handle with a hand grip portion  126  that extends generally vertically. The handle  124  has a longest dimension in the direction of a handle longitudinal axis  128 . As exemplified, the handle longitudinal axis  128  may be generally transverse to the apparatus longitudinal axis  110 . 
     The handle  124  may be a pistol grip handle with a handle upper end  130  of the pistol grip handle mounted to a lower end of the surface cleaning apparatus  100 . The handle  124  may extend away from the main body housing  122 . The handle may be below the suction motor, the pre-motor filter, and/or the air treatment assembly. Arranging the handle below a heavy and/or bulky component of the surface cleaning apparatus  100  may result in a more desirable hand-feel of the surface cleaning apparatus  100 . 
     The handle upper end  130  may be mounted to one or more of a suction motor housing, the pre-motor filter housing and the air treatment assembly. For example, the handle upper end  130  may be mounted to each of the air treatment assembly and the pre-motor filter housing. Alternately, the handle upper end  130  may be mounted to each of the pre-motor filter housing and the suction motor housing. 
     It will be appreciated that the main body housing  122  and/or handle  124  may be in other configurations, shapes, and/or positions in other embodiments. 
     The illustrated example surface cleaning apparatus is a hand vacuum cleaner, which may also be referred to as a “handvac” or “hand-held vacuum cleaner”. As used herein, a hand vacuum cleaner is a vacuum cleaner that can be operated to clean a surface generally one-handedly. That is, the entire weight of the vacuum may be held by the same one hand used to direct a dirty air inlet of the vacuum cleaner with respect to a surface to be cleaned. For example, the handle and a clean air inlet may be rigidly coupled to each other (directly or indirectly) so as to move as one while maintaining a constant orientation relative to each other. This is to be contrasted with canister and upright vacuum cleaners, whose weight is typically supported by a surface (e.g., a floor) during use. 
     It will be appreciated that any one or more of the features of the surface cleaning apparatus  100  set out herein may alternately be used in any type of surface cleaning apparatus, such as an upright surface cleaning apparatus, a stick vac, a canister surface cleaning apparatus, an extractor or the like. It will also be appreciated that a surface cleaning apparatus may use any configuration of the operating components and the airflow paths exemplified herein. 
     As exemplified in  FIGS.  3  and  4   , it will also be appreciated that the surface cleaning apparatus  100  may form a part of a larger surface cleaning apparatus  152  (e.g., a stick vacuum cleaner). As exemplified, the surface cleaning apparatus  100  may be mounted to an outlet end of an upright support member or rigid wand or external conduit  140  (e.g., a wand of a stick vacuum). 
     The external conduit  140  may be a rigid conduit (e.g., formed of rigid plastic and/or metal). The external conduit  140  extends between an external conduit inlet end  142  and an external conduit outlet end  144 . The external conduit  140  includes an external conduit sidewall  146  extending between the external conduit inlet end  142  and the external conduit outlet end  144 . The external conduit  140  may be a linear rigid conduit extending linearly along an external conduit longitudinal axis  148  between the external conduit inlet end  142  and the external conduit outlet end  144 , the longitudinal axis extending along a longest dimension of the external conduit  140 . Alternatively, or additionally, the external conduit  140  may include a flexible portion and/or a non-linear portion. For example, the external conduit  140  may include a flexible hose portion and a rigid portion. 
     Optionally, the external conduit  140  is mounted (e.g., rotationally such as pivotally mounted) at an upstream end  142  to a surface cleaning head  150 , whereby the surface cleaning apparatus forms a stick type surface cleaning apparatus  152 . It will be appreciated that the external conduit  140  may be provided without the surface cleaning head  150 . For example, the external conduit  140  may be removably receivable in the surface cleaning apparatus  100  whereby an effective nozzle of the surface cleaning apparatus  100  is extended to the upstream end  142 , thereby extending the reach of the hand vacuum cleaner for, e.g., above floor cleaning. 
     As exemplified in  FIGS.  3  and  4   , the external conduit  140  and the surface cleaning head  150  are parts of a floor cleaning unit  154  to which the surface cleaning apparatus  100  may be removably mountable to form the stick type vacuum  152 . 
     In some embodiments, the surface cleaning apparatus  100  is operable in different modes, and may include a mode for use with the floor cleaning head  150  and a mode for use without the floor cleaning head. For example, when the surface cleaning apparatus  100  is mounted to the floor cleaning unit  154 , the surface cleaning apparatus  100  may be operable in a floor cleaner mode. When the surface cleaning apparatus  100  is removed from the floor cleaning unit  154 , the surface cleaning apparatus  100  may be operable in an above floor cleaning mode. The floor cleaning mode may provide a different (e.g., lesser) level of power to an air moving member of the hand vacuum unit than the above floor cleaning mode, resulting in, e.g., a different efficiency, run time, and/or physical configuration of the surface cleaning apparatus  100 , as discussed further elsewhere herein. 
     With the surface cleaning apparatus  100  mounted to the floor cleaning unit  154 , the surface cleaning head  150  and the external conduit  140  may be moveably mounted between an upright storage position ( FIG.  3   ) and a reclined cleaning position ( FIG.  4   ). As exemplified, the surface cleaning head  150  and the external conduit  140  are joined by a pivot joint  156  about which they pivot relative to one another to move between the upright storage position and the reclined cleaning position. 
     As exemplified in  FIGS.  5  and  6   , an apparatus air flow path  160  extends from an apparatus dirty air inlet  162  to an apparatus clean air outlet  164  (clean air outlet  164  is shown in, e.g.,  FIG.  1   ). 
     The apparatus dirty air inlet  162  may be provided at the apparatus front end  102 . As exemplified, the apparatus dirty air inlet  162  may be provided at the apparatus upper end  106 . The apparatus dirty air inlet  162  may be at a forwardmost part of the surface cleaning apparatus  100 , and may be directed forwardly as exemplified (i.e., opening forwardly). It will be appreciated that the dirty air inlet may be located elsewhere, such as the lower end of the lower end of the air treatment assembly. 
     The apparatus dirty air inlet  162  may be provided at an inlet end of an inlet conduit  170 . The inlet conduit extends from the apparatus dirty air inlet  162  rearwardly. 
     The inlet conduit  170  extends from an inlet conduit inlet end  172  to an inlet conduit outlet end  174 . Optionally, as exemplified, the inlet conduit outlet end  174  is within an internal chamber of the surface cleaning apparatus  100  (e.g., an air treatment chamber which may be a cyclone chamber). Accordingly, the inlet conduit may be inserted into the air treatment chamber. Alternately, the inlet conduit  170  may be provided external to the internal chamber and may have an outlet port that is also an inlet port provide din a wall (e.g., a sidewall) of the internal chamber. The inlet conduit  170  may be a generally linear conduit having an inlet conduit longitudinal axis  176  along a longest dimension of the inlet conduit and extending between the inlet conduit inlet end  172  and the inlet conduit outlet end  174 . The inlet conduit longitudinal axis  176  may extend between the apparatus front end  102  and the apparatus rear end  104 , and, as exemplified, may be generally horizontal when the apparatus upper end  106  is above the apparatus lower end  108 . The inlet conduit longitudinal axis  176  may be generally parallel to the apparatus longitudinal axis  110 . 
     As exemplified, the inlet conduit  170  may form a nozzle  180  of the surface cleaning apparatus  100 . Alternatively, or additionally, the inlet conduit  170  may be connected or directly connected to an accessory, such as the external conduit  140  (e.g., a wand). The accessory may be any suitable accessory tool such as a rigid air flow conduit (e.g., an above floor cleaning wand), a crevice tool, a mini brush, and the like. The accessory may be coupled to the surface cleaning apparatus  100  such that the accessory is in air flow communication with the dirty air inlet (e.g., in air flow communication with the inlet conduit  170 ). For example, the accessory may be or include a conduit (e.g., external conduit  140 ), and the conduit of the accessory may be received within the inlet conduit  170  or may receive the inlet conduit  10  within the accessory conduit. Optionally, one or more releasable fasteners may be used to couple the accessory to the surface cleaning apparatus  100 , such as clips or magnets. Alternatively, or additionally, the accessory may be held in air flow communication with the dirty air inlet via a friction fit (e.g., between an outer diameter of an accessory conduit and an inner diameter of the inlet conduit  170 , or vice versa). Alternately, it will be understood that the inlet conduit  170  could be slideably receivable in an accessory conduit. 
     As exemplified in  FIGS.  1  and  2   , the inlet conduit  170  may project forward alone. In other words, the inlet conduit  170  may extend forwardly of the rest of the surface cleaning apparatus  100 , with no other member of the surface cleaning apparatus  100  extending forwardly with the inlet conduit  170 . Alternatively, as exemplified in  FIGS.  46  to  54   , one or more additional component, such as an electrical coupler  380 , may project forward alongside the inlet conduit. As exemplified in  FIGS.  46  to  54   , the inlet conduit  170  may be part of the main body  120 . Where the main body  120  includes a rearward portion (e.g., main body housing  122 ) and the inlet conduit is at the apparatus front end  102 , the inlet conduit  170  may be joined to the rearward portion by any suitable structure, e.g., a portion of the main body housing  122 , a plurality of discrete arms in parallel to one another, or, as exemplified in  FIGS.  46  and  47   , a main body shell  182 . Alternatively, as exemplified in  FIGS.  1  and  2   , the inlet conduit  170  is part of a front portion of a body that is removably coupled to the main body  120  (e.g., the air treatment assembly  200 , in the exemplary embodiment). 
     It will also be appreciated that, in some embodiments, the surface cleaning apparatus  100  may not include an inlet conduit  170 , and the apparatus dirty air inlet  162  may instead open directly into a downstream chamber (e.g., an air treatment chamber  210 ) rather than being at an upstream end of a conduit. However, a conduit  170  allows a nozzle  180  to be formed for application to a surface that is to be cleaned. 
     As exemplified in  FIGS.  1  and  2   , the apparatus clean air outlet  164  may be provided at a lateral portion of the apparatus rear end  104 . The apparatus clean air outlet  164  may include a grill  190  located on a lateral surface of the surface cleaning apparatus  100 . As exemplified, the apparatus clean air outlet  164  may include openings (e.g., grill  190 ) on each lateral side of the apparatus rear end  104 . The openings on each of the lateral sides of the apparatus rear end  104  may be generally equivalent in cross sectional area to encourage balanced air flow out each side of the surface cleaning apparatus  100  through the apparatus clean air outlet  164 . 
     As exemplified, the apparatus rear end  104  may have a main body housing sidewall  192  that extends to a main body rear face  194  of the main body housing  122 . The apparatus clean air outlet  164  may be provided in the main body housing sidewall  192 . Optionally, the main body housing sidewall  192  is a generally cylindrical wall, and the main body rear face  194  includes a rear surface of a planar rear wall  196 , as exemplified. Optionally, the main body rear face  194  is a rear face of the surface cleaning apparatus  100  as a whole (i.e., nothing overlying the main body rear face  194 ). However, it will be appreciated that in some embodiments the surface cleaning apparatus  100  may include a body overlying the rear face  194  of the housing  122 , such as a user interface support body as discussed further elsewhere herein. 
     It will also be appreciated that the apparatus dirty air inlet  162  and/or the apparatus clean air outlet  164  may be provided at different locations and/or be of different configurations. 
     As exemplified in  FIGS.  5  and  6   , the surface cleaning apparatus  100  includes an air treatment assembly  200 . The apparatus air flow path  160  extends through the air treatment assembly  200 . The air treatment assembly  200  is configured to remove particles of dirt and other debris from the airflow and/or otherwise treat the airflow. The air treatment assembly includes one or more air treatment members  202 . Any air treatment member or members known in the art may be used. For example, the surface cleaning apparatus may use one or more cyclones, bags, screens, physical filter media (e.g., foam, felt, HEPA) or the like. The air treatment assembly  200  may be removably mounted between the apparatus dirty air inlet  162  and the main body housing  122 . As exemplified in  FIGS.  63  to  70   , the air treatment assembly  200  may be removably receivable in a cavity between the inlet conduit  170  and the main body housing  122 . Alternatively, as exemplified in  FIGS.  1  and  2   , the air treatment assembly  200  may include the inlet conduit  170  (e.g., with the inlet conduit  170  extending forwardly from the air treatment assembly  200 , optionally from an upper portion of the front end of the air treatment assembly  200 ), and the air treatment assembly  200  may be removably coupled to the main body housing  122 , e.g., a front end of the main body. The air treatment assembly  200  may be removeable from the main body housing  122  in any suitable direction, such as upwardly and/or downwardly and/or forwardly (e.g., as exemplified in  FIG.  2   ). 
     It will be appreciated that the air treatment assembly  200  may include any suitable number of air treatment stages, each with any suitable number of air treatment members in parallel. For example, the air treatment member  202  may include a first separation stage with a single air treatment member (e.g., a cyclone or momentum separator) and a downstream second stage comprising a plurality of air treatment members (e.g., an array of mini cyclones in parallel with one another). 
     As exemplified in  FIGS.  5  and  6   , the air treatment assembly  200  may comprise a single cleaning stage. A single cleaning stage may include, e.g., a single cyclonic stage (which may comprise one or more cyclones in parallel), or a single non-cyclonic momentum separator chamber. As exemplified, the single cleaning stage may comprise a single air treatment member, and, as such, the air treatment assembly  200  may be referred to as air treatment member  202 . 
     An air treatment member longitudinal axis  204  extends between an air treatment member first end  206  (e.g., front end) and an air treatment member second end  208  (e.g., rear end). As exemplified, the air treatment member longitudinal axis  204  may be generally parallel to the apparatus longitudinal axis  110  and/or the inlet conduit longitudinal axis  176 . The air treatment member longitudinal axis  204  may be generally transverse to the handle longitudinal axis  128 . The air treatment member longitudinal axis  204  may be generally horizontal when the apparatus upper end  106  is above the apparatus lower end  108 . 
     The exemplary air treatment member  202  includes an air treatment chamber  210 . The air treatment chamber  210  has a chamber housing  212  having a chamber first end  214  and a chamber second end  216  axially spaced from the chamber first end  214  along the chamber longitudinal axis  218 . The air treatment chamber  210  may be a cyclone chamber, as exemplified, and the chamber longitudinal axis  218  may be a cyclone axis of revolution. The chamber longitudinal axis  218  may be a generally horizontal axis when the apparatus upper end  106  is above the apparatus lower end  108 , and may extend between the apparatus front end  102  and the apparatus rear end  104 . The chamber first end  214  may be a front end and the chamber second end  216  may be a rear end. 
     The air treatment chamber  210  includes a chamber sidewall  220  extending between the chamber first end  214  and the chamber second end  216 . The air treatment chamber sidewall  220  may be a generally cylindrical sidewall. A generally cylindrical sidewall encourages cyclonic air flow within the chamber. The air treatment chamber sidewall  220  may have a generally constant diameter along the chamber longitudinal axis  218 . However, it will be appreciated that any suitable shape may be used for the air treatment chamber. 
     The chamber longitudinal axis  218  may be the same as the air treatment member longitudinal axis  204 . The air treatment member longitudinal axis  204  may be centrally located within the air treatment chamber  210 . The air treatment member longitudinal axis  204  may be a central axis extending through a radial centre of the chamber sidewall  220 . The chamber longitudinal axis  218  may extend along a longest dimension of the air treatment chamber  210 , as exemplified. As exemplified, the air treatment chamber  210  may include a chamber first end wall  222  (e.g., front end wall) at the chamber first end  214  and a chamber second end wall  224  (e.g., rear end wall) at the chamber second end  216 . The end walls may close the ends of the chamber. The chamber sidewall  220  may extend between the chamber first end wall  222  to the chamber second end wall  224 . The first end wall may be a front end wall and the second end wall may be a rear end wall. The first and second end walls may each extend generally vertically and/or transversely when the apparatus upper end  106  is above the apparatus lower end  108 . 
     One or both of the end walls, or a portion of one or each of the end walls, may be openable to, e.g., allow for dirt removal. Alternatively, or additionally, the sidewall or a portion thereof may be openable. As exemplified, the chamber first end wall  222  may be pivotally coupled to the chamber sidewall  220  at pivot joint  226 . The chamber first end wall  222  may be openable by pivoting the first end wall  222  about a pivot axis  228  of the pivot joint  226  (see, e.g.,  FIG.  2   ). The pivot axis  228  may be generally perpendicular to the apparatus longitudinal axis  110  and/or the apparatus vertical axis  112 . Optionally, as exemplified, the inlet conduit  170  may be part of the openable first end  222 , and may be provided on a front face of the air treatment assembly  200  such as on the openable assembly first wall  222 . Alternately the inlet conduit  170  may remain in position while a portion of the first wall  222  below the inlet conduit  170  is opened, e.g., pivoted open. The openable end wall or portion thereof may be latched shut, e.g., by a latch  229  opposite the pivot joint  226 . 
     The air treatment inlet  230  includes a chamber inlet opening  234 , and the air treatment outlet  232  includes a chamber outlet opening  236 , with the air flow path extending through the chamber inlet opening  234  and the chamber outlet opening  236 . However, it will be appreciated that in some embodiments the air treatment inlet  230  and/or the air treatment outlet  232  may include more than just an opening. As exemplified, the air treatment outlet  232  may include a screen that may be a vortex finder  238  extending into the air treatment chamber, and the air treatment inlet  230  may include a projecting conduit  240  extending into the air treatment chamber  210 . Including bodies that extend into the air treatment chamber  210  allows for greater control over air flow within the chamber and/or a more compact construction. It will be appreciated that the air treatment member may have any air inlet and any air outlet known in the art. 
     Optionally, the treatment inlet  230  comprises a projecting conduit  240  into which the outlet end of the inlet conduit  170  may be removably insertable. It will be appreciated that part or all of the air treatment inlet  230  may be positioned exterior or interior of the air treatment member. For example, the air treatment inlet  230  may be exterior (e.g., above) the air treatment chamber and a sidewall of the air treatment inlet  230  may have a port that communicates with the air treatment chamber via a port in the sidewall of the air treatment chamber. Alternately, the air treatment inlet  230  may have an outlet end that is within the air treatment chamber. In such a case, the air treatment inlet  230  may be located radially inward of the chamber sidewall  220 . The air treatment inlet  230  may extend axially inward of the chamber first end  214  and have an outlet end that is located axially inwardly of the chamber second end  216 , as exemplified. As exemplified, the air treatment inlet  230  may extend axially into the air treatment chamber  210  by an axial projecting length  242 . The axial projecting length  242  may be between 10 mm and 100 mm, between 25 mm and 75 mm, or, optionally, between 40 mm and 60 mm. Optionally, the air treatment inlet  230  located radially in the air treatment chamber  210  by a radial projecting distance  244  that is between 0.1 times and 0.5 times the cyclone diameter  246 , between 0.25 times and 0.45 times the cyclone diameter  246 , or, optionally, between 0.3 times and 0.4 times the cyclone diameter  246 . However, it will also be appreciated that in some embodiments the air treatment inlet may be located in the chamber sidewall  220  of the air treatment assembly (i.e., include or consist of an opening through the chamber sidewall  220 ). 
     The air treatment inlet  230  may optionally have an axial inner (outlet) end that is closer to the chamber first end  214  than the chamber second end  216 , and may project into the air treatment chamber  210  from the air treatment chamber first end  214 . An inlet at the air treatment first end  214  allows for a more compact construction. However, it will be appreciated that the air treatment inlet  230  may alternatively be located at a rear or midway position of the air treatment assembly  200 , and may be located on the same or the opposite end from the air treatment outlet  232 . The exemplary air treatment member  202  is a uniflow cyclone, however it will be appreciated that in other embodiments the air treatment member  202  may be a reverse flow cyclone. 
     It will be appreciated that in embodiments in which the air treatment inlet  230  projects into the air treatment chamber  210 , the air treatment inlet  230  includes an inlet upstream end  250  and an inlet downstream or outlet end  252 . The air treatment inlet  230  includes an inlet longitudinal axis  254  extending between the inlet upstream end  250  and the inlet downstream end  252 . The inlet upstream end  250  includes an inlet upstream opening  256  through which the air flow path enters the air treatment inlet  230  and the inlet downstream end includes an inlet downstream opening  258  through which the air flow path exits the air treatment inlet  230  and enters the air treatment chamber  210 . The air treatment inlet  230  includes an inlet sidewall  260  extending between the inlet upstream end  250  and the inlet downstream end  252 . The inlet upstream opening  256  may be an axial opening through which the inlet longitudinal axis  254  extends. The air treatment inlet may extend axially to an open downstream end which may be the inlet downstream opening  258 . Alternately, or in addition, the inlet downstream opening  258  may be a sidewall opening in the inlet sidewall  260 . 
     The air treatment assembly  200  includes a dirt collection region  300 . In some embodiments, the dirt collection region  300  may be external to the air treatment chamber  210 . The dirt collection region may be located in a separate dirt collection chamber from the air treatment chamber  210 . The separate dirt collection chamber may communicate with the air treatment chamber  210  via a dirt outlet (e.g., an opening in a wall of the air treatment chamber or a gap between walls of the air treatment chamber). 
     Alternatively, as exemplified, the dirt collection region  300  may be an area of the air treatment chamber  210  (i.e., is internal to the air treatment chamber  210 ). The dirt collection region  300  may include, e.g., a lower portion of the air treatment chamber  210 . The dirt collection region  300  may be at the air treatment front end  206  and/or the air treatment rear end  208 . The dirt collection region  300  may be axially outward (e.g., forward) of the chamber inlet port  294  and/or axially outward (e.g., rearward) of an air permeable portion of the air treatment outlet  232 . 
     It will be appreciated that the air treatment assembly  200  may include any suitable number of discrete dirt collection regions  300 . In some embodiments, the air treatment assembly  200  may include separate collection regions for fine dirt and for coarse dirt, or separate dirt outlets to a common dirt collection chamber for fine dirt and for coarse dirt. It will be understood that the air treatment chamber  210  and dirt collection region  300  may be of any configuration suitable for separating dirt from an air stream and collecting the separated dirt, respectively. 
     As exemplified in  FIGS.  7  to  10   , the air treatment assembly  200  may include a closure member  310  selectively closing a portion of the air flow path through the air treatment assembly  200  such that air flow therethrough is inhibited. Where the air treatment assembly  200  includes the air treatment chamber  210 , the closure member  310  may selectively close the air treatment inlet  230 , such as by closing the chamber inlet opening  234  or fully blocking the air flow path within a conduit of the air treatment inlet  230 . 
     The surface cleaning apparatus  100  may include a closure seat  312  against which the closure member  310  seats when closed (see for example  FIG.  7   ). The closure member  310  may rest against the closure seat  312  at each point about a perimeter  314  of the closure member  310 . The closure seat  312  may face upstream or downstream, and a downstream surface or an upstream surface of the closure member  310  may seat against the closure seat when the closure member  310  is closed. Alternatively, the closure member  310  may be received within a conduit in the closed position without seating against a seat, and the surface cleaning apparatus  100  may not include the closure seat  312  (see for example  FIGS.  31  and  32   ). Optionally, the closure member  310  includes a sealing material thereon to be sandwiched (e.g., at each point around a perimeter of the closure member  310 ) between the closure member  310  and conduit walls or a closure seat  312  when the closure member  310  is closed. 
     Optionally, the closure member  310  is biased to the closed position (e.g.,  FIG.  7   ). The surface cleaning apparatus  100  may include a closure biasing member  316  (e.g., a spring ora compressible balloon, an embodiment exemplified in  FIGS.  36  and  37   ) biasing the closure member to the closed position. Optionally, the closure member  310  is a generally planar member, as exemplified in  FIGS.  36  and  37   . Optionally, the closure member  310  is a curved member. 
     The closure member  310  may be operable to close the apparatus air flow path  160  to prevent dirt from traveling up the path towards the apparatus dirty air inlet  162 . For example, the closure member  310  may prevent dirt from falling out of the surface cleaning apparatus  100  when the surface cleaning apparatus  100  is not operating (i.e., when the suction motor is not powered up). It will be appreciated that the closure member  310  may be used when the dirt collection region  300  is an internal dirt collection region within the air treatment chamber  210 . The closure member  310  may be particularly useful with an internal dirt collection region  300  to prevent dirt from retreating along the air flow path out of the air treatment chamber  210 . 
     As exemplified in  FIG.  5   , the surface cleaning apparatus  100  also includes an air moving member  320 . The apparatus air flow path  160  extends through the air moving member  320 . The air moving member  320  is provided to generate vacuum suction through the air flow path  160 . The air moving member may include a suction motor and fan assembly  322 , which may be referred to as suction motor  322 . 
     The suction motor  322  is contained within a suction motor housing  324 . The suction motor housing  324  may form part of the outer surface of the main body housing  122 , or may be internal thereto. The suction motor housing  324  may be of any suitable construction, including any of those exemplified herein. 
     The suction motor  322  in the illustrated example is positioned downstream from the air treatment member  202 , although it will be appreciated that the suction motor  322  may be positioned upstream of the air treatment member  202  (e.g., a dirty air motor) in alternative embodiments. As exemplified, the motor  322  may be rearward of the cyclone air treatment assembly  200 . The suction motor  322  may be located at the apparatus rear end  104 , and may be located at the apparatus upper end  106 , as exemplified. Air may travel rearwardly from the air treatment assembly  200  to the suction motor  322 , and air flow direction between the air treatment member  202  and the suction motor  322  may have a rearward component at each point along the way. 
     The suction motor  322  rotates about a central motor axis of rotation  326 . Preferably, when the apparatus upper end  106  is positioned above the apparatus lower end  108 , the motor axis of rotation  326  is oriented generally horizontally and extends between the apparatus front end  102  and the apparatus rear end  104 . In other examples, however, the motor axis of rotation  326  may extend at any angle to the horizontal, or it may extend vertically. Accordingly, the suction motor  322  may be oriented in any direction within the surface cleaning apparatus  100 . The suction motor axis of rotation  326  may be spaced (e.g., vertically spaced) from the apparatus longitudinal axis  110 , or it may be coaxial therewith as exemplified. As exemplified, the suction motor axis of rotation  326  may intersect the air treatment assembly  200 . 
     The surface cleaning apparatus  100  may include one or more filters, such as a pre-motor filter  330  in the air flow path  160  upstream of the suction motor  322  (e.g., upstream of the motor  322  and downstream of the air treatment assembly  200 ) and/or a post-motor filter  332  in the air flow path  160  downstream of the suction motor  322 . The pre-motor filter  330  and the post-motor filter  332  may be formed from any suitable physical, porous filter media and may have any suitable shape, including the examples disclosed herein. For example, the pre-motor filter  330  and/or the post-motor filter  332  may be one or more of a foam filter, felt filter, HEPA filter, other physical filter media, electrostatic filter, and the like. Optionally, one or both of the premotor filter  330  and the post motor filter  332  includes a series of screens, and, optionally, each downstream screen of the filter has finer pores than the preceding upstream screen. 
     The pre-motor filter  330  may be provided in a pre-motor filter housing  334 . The pre-motor filter housing  334  may be of any suitable construction, including any of those exemplified herein. The pre-motor filter housing  334  may be operable or accessible to allow the pre-motor filter  330  to be cleaned and/or replaced. As exemplified, the suction motor axis of rotation  326  may intersect the pre-motor filter  330 . 
     As exemplified in  FIGS.  62  to  68   , the pre-motor filter  330  may be provided as part of the air treatment assembly  200  and removable therewith. The pre-motor filter  330  may be received in a pre-motor filter housing  334  that is built into the air treatment assembly  200 . Alternatively, as exemplified in  FIG.  5   , the pre-motor filter  330  may be part of the main body housing  122  (e.g., part of a front end, as exemplified) and not removeable as part of the air treatment assembly  200 . In such an embodiment, the front end of the pre-motor filter may be revealed when the air treatment assembly is removed. 
     The pre-motor filter  330  may come in any suitable shape or location, however, as exemplified, the pre-motor filter  330  may have a longest dimension in a longitudinal (horizontal) direction along a pre-motor filter longitudinal axis  336 . The pre-motor filter may be a donut filter, with a cylindrical body of filtration material surrounding a central cavity, as illustrated. The donut filter may be arranged with the central cavity extending generally horizontally, with an upstream end closed by a filter end cap  338  and the downstream end open (e.g., into the suction motor housing  324 , as exemplified). The pre-motor filter longitudinal axis  336  may be generally parallel to and/or coaxial with the apparatus longitudinal axis  110 , the air treatment longitudinal axis  204 , the motor axis of rotation  326 , and/or the inlet conduit longitudinal axis  176 . The donut filter may be cylindrical or frusto-conical in shape. 
     The post-motor filter  332  may be provided in a post-motor filter housing  340 . The post-motor filter housing  340  may form part of the outer surface of the main body housing  122 . The post-motor filter housing  340  may be of any suitable construction, including any of those exemplified herein. The post-motor filter housing  340  may be openable or accessible to allow the post-motor filter  332  to be cleaned and/or replaced. 
     The post-motor filter  332  may be located radially outwards of the suction motor  322 , as exemplified. Optionally, the post-motor filter  332  may be sandwiched between the suction motor housing  324  and the chamber sidewall  220 . 
     As exemplified, power may be supplied to the surface cleaning apparatus  100  (e.g., to components or elements such as the suction motor  322 ) from an on-board energy storage member  350  (e.g., one or more capacitors or batteries). For example, the on-board energy storage member  350  may be a battery or a plurality of batteries. 
     The on-board energy storage member  350  may be provided in a pack (e.g., a removeable pack). The pack may be a battery pack. Optionally, the energy storage member  350  is provided at a base of the handle  124 . The energy storage member  350  may be provided at a lower end  352  of a pistol grip handle  124 . Optionally, the energy storage member  350  is opposite the motor  322  across the handle  124 . The handle longitudinal axis  128  may extend through each of the motor  322  and the energy storage member  350 . However, it will be appreciated that the on-board energy storage member and/or pack may be provided at any configuration and/or location in the surface cleaning apparatus  100 . 
     It will be appreciated that in some examples, the surface cleaning apparatus  100  may alternatively or additionally include a power cord to supply power to the components of the surface cleaning apparatus  100  (e.g., the motor  322 ) directly, and/or to supply power to the on-board energy storage member  350  (e.g., a capacitor or battery) to supply power to powered components (e.g., the suction motor  322 ). 
     As exemplified in  FIG.  11   , it will also be appreciated that the surface cleaning apparatus  100  includes a user interface  360 . The user interface  360  may be communicatively coupled to a control system  370  of the surface cleaning apparatus  100 . The control system  370  may include one or more onboard processors communicatively coupled to one or more on board data storage systems storing instructions. The instructions include routines or schedules for operating the surface cleaning apparatus  100 , and may include routines or schedules for operating the surface cleaning apparatus  100  in response to input. The input may be user input (e.g., via the user interface  360 ), such as turning the apparatus on or off or selecting an operational mode. The input may be from one or more components of the surface cleaning apparatus  100 , such as from an on-board sensor. The surface cleaning apparatus may include one or more sensors. It will be appreciated that any suitable sensor may be included, including any of the sensors described herein. The control system  370  (e.g., the one or more processors) may be communicatively coupled to one or more sensors and/or actuators to receive input and/or provide operation commands thereto. 
     The control system  370  (e.g., the one or more processors) may be communicatively coupled to the user interface to receive user input and/or provide information. The user interface  360  provides information to the user and/or includes at least one control operable by the user (e.g., an on/off control, which may be a button or touch sensitive area of the user interface). The user interface  360  may provide information about at least one operating mode of the surface cleaning apparatus  100  (e.g., information about which mode is active). The user interface  360  may provide information about a charge level of an energy storage member  350 . The user interface may include at least one interface toggle  362 . The interface toggle  362  may be referred to as a control of the surface cleaning apparatus. The interface toggle  362  may be a soft toggle (e.g., a touch sensitive area of the touchscreen) or a physically moveable toggle such as a slider, a pivoting switch, or a depressible button. The user interface may include an information display  364 , such as a touchscreen, a display screen, or an illuminable icon. 
     It will be appreciated that the control system  370  may be communicatively coupled to one or more powered component of the surface cleaning apparatus to control operations thereof (e.g., to activate, deactivate, and/or change a setting such as a mode thereof). A powered component may be, e.g., a powered valve, a powered actuator, or a powered interface (e.g., a display screen, a touchscreen or illuminated icon), such as any of the powered components described subsequently herein. A powered component may be coupled to a power supply of the surface cleaning apparatus, such as a power supply member or a power cord, to receive power therefrom. 
     A powered actuator may be, e.g., a solenoid or another electromechanical actuator such as a linear actuator or a motor which may be provided for any use described subsequently herein. It will be appreciated that in some embodiments a powered actuator may be independent from the control system  370 , such as a powered actuator that is controlled by a simple circuit. A simple circuit may not include a processor or a data storage device, such as a circuit with a toggle (e.g., a switch, slider or button) that closes the circuit when activated and breaks the circuit when deactivated. 
     It will be appreciated that the surface cleaning apparatus may include one or more actuators that is unpowered or that may be realized by a powered component or an unpowered component as described subsequently herein. An unpowered actuator may be, e.g., an aneroid capsule or piston. It will be appreciated that an actuator as described herein may be powered or unpowered, unless otherwise specified. An actuator may include a mechanical coupling to a moveable member which the actuator is provided to move. An actuator may be a linear actuator. An actuator may be a dedicated actuator provided to move only one movable member, or may be a common actuator operable to move more than one movable member (e.g., at the same time, or separately as directed by the control system  370 ). 
     The user interface  360  may provide information about at least one operating mode of the surface cleaning apparatus  100 . The user interface  360  may include a button that a user may press to toggle between, e.g., operational states of the surface cleaning apparatus  100 . For example, the user may toggle between a floor cleaning mode in which the suction motor  322  is provided with a first power level and an above floor cleaning mode in which the suction motor  322  is provided with a second power level that is higher than the first power level (i.e., to rotate the fan faster). In some embodiments, the user interface  360  may provide information about a charge level of the energy storage member  350 . 
     It will be appreciated that the user interface  360  may be provided at any suitable location on the surface cleaning apparatus  100 , and may be any suitable user interface. Optionally, the user interface  360  is provided on the handle and/or an upper surface of the surface cleaning apparatus  100  for ease of access or visibility, as discussed further elsewhere herein. 
     Optionally, as exemplified in  FIGS.  46  and  47   , an electrical connector  380  may be provided at the front end  102  to provide electricity to an attachment (e.g., the floor cleaning head) from the surface cleaning apparatus  100  (e.g., from an optional on-board energy storage member  350 ). The electrical connector  380  may be provided adjacent the dirty air inlet  162  (e.g., to be contacted by an electrical connector of the attachment adjacent the air outlet of the attachment). As exemplified, the electrical connector  380  may be directly beside (e.g., above) the dirty air inlet  162 . In other words, the electrical connector  380  may be close enough to the inlet  162 to be mated to an electrical connector mounted on a wand that is joined to the inlet  162 . For example, the electrical connector may be within 10 cm, 5 cm, or 3 cm of the inlet  162 . 
     In some embodiments, the portion of the external conduit  140  (e.g., the wand) which is connected to (e.g., inserted into) the nozzle  180  (e.g., into the air treatment inlet  230  and/or the inlet conduit  170 ) includes an external conduit electrical connector  380  that is also inserted into the nozzle. The external conduit electrical connector  380  may be on an exterior surface of the sidewall of the external conduit  140 , as exemplified. Optionally, the external conduit electrical connector is also an alignment member. Optionally, the external conduit electrical connector  380  is at the end of the external conduit  140 . 
     General Description of a Docking Station 
     As exemplified in  FIGS.  48  to  50   , it will be appreciated that the surface cleaning apparatus  100  may, optionally, be docked with a docking station  390 . The docking station  390  may evacuate and/or charge the surface cleaning apparatus  100  when the surface cleaning apparatus  100  is docked. 
     As exemplified in  FIGS.  48  to  50   , the docking station  390  may include an evacuation air flow passage  392  between an evacuation air inlet  394  and an evacuation air outlet  396 . An evacuation air treatment assembly  398  is provided in the evacuation air flow passage  392  to separate dirt. The docking station  390  may include an evacuation air moving member  400  in the air flow path  160 . It will be appreciated that in some embodiments, as exemplified in  FIGS.  67  and  68   , the docking station  390  may not include an air moving member, with air movement through the air flow path  160  driven by an external air moving member, such as the motor  322  of a docked surface cleaning apparatus  100 . 
     The docking station  390  may be used to evacuate the surface cleaning apparatus  100 . When the surface cleaning apparatus  100  is docked with the docking station  390 , an evacuation air flow path  392  may extend through the docking station  390  and the docked surface cleaning apparatus  100 . The evacuation air flow path  392  extends from an evacuation dirty air inlet  394  to an evacuation clean air outlet  396 . It will be appreciated that the evacuation dirty air inlet  394  may be provided at any suitable location of the surface cleaning apparatus  100  or the docking station  390 . It will also be appreciated that the evacuation clean air outlet  396  may be provided at any suitable location of the surface cleaning apparatus  100  or the docking station  390 . It will also be appreciated that the evacuation air flow path  392  may include a portion of the apparatus air flow path  160 . Optionally, the evacuation air flow path  392  does not include all of the apparatus air flow path  160 . The evacuation air flow path  392  may not include the dirty air inlet  162  and/or clean air outlet  164 . For example, one or more valves may close off a portion of the apparatus air flow path  160  and/or open a portion of the evacuation air flow path  392 , and may be moved manually, in response to a user input or automatically in response to the surface cleaning apparatus being docked. 
     The air moving member  400  is configured to move air from the surface cleaning apparatus  100  into the docking station upstream of at least one docking station air treatment member  202  through an evacuation opening  410  in the surface cleaning apparatus  100 . The evacuation opening  410  may be a selectively closeable opening, such that the evacuation opening  410  may be closed when the surface cleaning apparatus  100  is not docked. Although it will be appreciated that in some embodiments the evacuation opening  410  may not be closeable, for example the evacuation opening may include the dirty air inlet of the surface cleaning apparatus  100  and may include the air treatment inlet  230  (i.e., air moves out the dirty air inlet  162  through the evacuation air flow path  392  during an evacuation operation). A selectively openable evacuation opening  410  may be opened in any suitable way, including manually or automatically. 
     it will be appreciated that the evacuation opening  410  may be any suitable opening, and may be part of the chamber first end  214 . The evacuation opening  410  may include or consist of the air treatment inlet  230  and the dirty air inlet  162 , which may be selectively closed by, e.g., the closure member  310  (see for example  FIG.  49   ). Alternately, part or all of the front wall of the air treatment assembly (e.g., the portion below the inlet conduit  170 ) may be openable. The evacuation opening  410  may alternately be a selectively closeable aperture through a sidewall of the air treatment assembly  200  (e.g., the chamber sidewall  220 ) or through an end wall of the air treatment assembly  200 . The evacuation opening may be a gap between walls when the walls are moved apart. The evacuation opening may be closed by a moveable flap or panel. The evacuation opening may be opened and/or closed by rotational or translational movement of a member which selectively closes the evacuation opening. It will be appreciated that the location and size of the evacuation opening  410  may be selected based on the configuration of the docking station  390 . 
     Dirt may be carried out of the surface cleaning apparatus  100  and into the docking station  390  through the evacuation opening when the evacuation opening is open. Dirt may be inhibited from moving through the evacuation opening when the evacuation opening is closed, such as by a moveable door. 
     The docking station  390  optionally provides a charge to the surface cleaning apparatus  100  to, e.g., charge an onboard energy storage member  350 . In some embodiments, the docking station  390  provides a charge to the surface cleaning apparatus  100  without being configured to evacuate the surface cleaning apparatus  100  (e.g., without including an air flow path or treatment member to receive dirt). The docking station  390  may include a cord to be plugged into, e.g., a residential outlet, to supply electrical power to the docking station  390 , to be supplied to the surface cleaning apparatus  100  and/or to an onboard component such as the motor  322 . 
     It will be appreciated that any suitable docking station  390  may be used, or the surface cleaning apparatus  100  may be used and provided without a docking station  390 . 
     Rib Arrester 
     The following is a description of a rib arrestor  420  provided in the air treatment assembly  200 , which may be used by itself or in combination with one or more of the air inlet with a side opening, the variable area inlet downstream opening, the curved closure member, the axially moving closure member, the withdrawable closure member, the closure member moved by a driving member, the openable chamber first end, the axially moveable chamber end, moving using fluid pressure, positioning of the user interface, the filter removeable past the user interface, the radially-removeable post-motor filter, the nested filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     In accordance with this aspect, as exemplified in  FIGS.  11  to  13   , the air treatment assembly  200  includes a rib  420  extending into a chamber of the assembly  200  from a wall of the chamber. The rib  420  interrupts air flow (cyclonic air flow if the chamber is a cyclone chamber) and encourages dirt accumulation adjacent the rib  420 . The rib  420  may be at one of the ends of the chamber, and optionally at an end at which an air outlet of the chamber is located. Accordingly, the rib may create an area at the air outlet end of the air treatment chamber which has diminished or minimal or no air circulation and, accordingly, dirt, e.g., finer dirt, may be accumulated therein. 
     Optionally, as exemplified in  FIG.  13   , the air treatment outlet  232  may comprise an outlet air permeable portion  422  and a downstream outlet air impermeable portion  424  through which the apparatus air flow path  160  extends. The outlet air permeable portion  422  may be an outlet porous portion comprising an outlet porous material  426 , e.g., a screen. The air treatment outlet  232  may include a central open region through which the air treatment longitudinal axis  218  extends, with a screen or other outlet porous material  426  through which the apparatus air flow path  160  passes. 
     As exemplified, the outlet air impermeable portion  424  and the outlet porous portion  422  are parts of a vortex finder  238  of a cyclone. In such an embodiment, the air treatment outlet  232  includes the vortex finder  238 , and may consist of the vortex finder  238 . 
     The outlet air impermeable portion  424  may be a conduit having an air impermeable sidewall extending between inlet and outlet ends, such as a linear cylindrical conduit as exemplified. The outlet porous portion  422  has an axially inward end  430  and an opposite axially outward end  432 . The axially outward end  432  is located at the inner end  434  of the outlet air impermeable portion  424 . The outlet air impermeable portion  424  extends between the inner end  434  and an outward end  436 . As exemplified, the outlet porous portion  422  may extend further inwardly into the air treatment chamber  210  fro the inner end  434  of the outlet air impermeable portion  424 . 
     As exemplified, the air impermeable portion  424  may include, or consist of, an annular portion of the vortex finder  238 . As exemplified, the air impermeable portion  424  may include an annular strip extending a predetermined axial length along the longitudinal axis  218 , and the strip may have a generally constant axial length around the circumference. For example, the axial length of the strip of the impermeable portion  242  may be between 1 mm and 10 mm, 2 mm and 8 mm, or about 5 mm. In some embodiments, the air impermeable portion may include a projecting portion  425  ( FIG.  11   ) extending further axially than the remainder. The projecting portion may comprise ribs that assist in maintaining the shape of the screen during use. 
     The rib  420  may extend co-extensively (i.e., with respect to the cyclone axis  218 ) along at least a portion of, and optionally all of, the air treatment chamber  210  in which the outlet air impermeable portion  424  of the air treatment outlet  232  is provided. The rib  420  and outlet air impermeable portion  424  may extend into the air treatment chamber  210  from a common wall. As exemplified, both the outlet air impermeable portion  424  and the rib  420  extend into the air treatment chamber  210  from the treatment chamber second end  216  (e.g., a rear end, and may extend from the treatment chamber second end wall  224 ). The rib  420  and outlet air impermeable portion  424  together form a dead zone  440  between the rib and the air impermeable portion. As exemplified, the dead zone  440  is at the treatment chamber second end  216 . 
     It will be appreciated that the rib  420  may extend further into the air treatment chamber  210  along the air treatment longitudinal axis  218  than the impermeable portion, or the impermeable portion may extend further into the air treatment chamber  210  along the air treatment longitudinal axis  218  than the rib, or the rib  420  and outlet air impermeable portion  424  may extend equally far into the air treatment chamber  210 . Optionally, the rib  420  extends into the air treatment chamber only coextensively with the outlet air impermeable portion  424 , and not with the outlet permeable portion  422 . In other words, the forward end of the rib is located at or rearward of the porous portion  422  and accordingly, the rib  420  may extend into the air treatment chamber  210  to a distance equal to or less than the outlet air impermeable portion  424 . Keeping the rib  420  from extending coextensively with the outlet air permeable portion  422  may reduce the obstruction of airflow into the permeable portion. 
     The rib  420  may extend inwardly, e.g., axially inwardly, into the air treatment chamber  210  from an end wall  224  of the air treatment chamber. However, it will be appreciated that the rib may be provided in any suitable location. For example, the rib may have a rear side that terminates prior to the end wall  224 . Accordingly, for example, the rib could extend rearward from the front end of the air impermeable portion  424  or rearward from a location rearward of the air impermeable portion  424  and may terminate at or forward of the rear wall  224 . As exemplified, the rib  420  extends into the air treatment chamber  210  from the air treatment chamber rear wall  224 . 
     The rib  420  may also extend inwardly, e.g., radially inwardly, from a sidewall  220  of the air treatment chamber and/or the air impermeable portion  424 . As exemplified, the rib  420  extends into the air treatment chamber  210  from the cyclone sidewall  220 . 
     As exemplified, the rib  420  is positioned between the air treatment outlet  232  and the cyclone sidewall  220 . Accordingly, the rib  420  is radially outward from the outlet air impermeable portion  424 . The rib may have a radial width equal to the distance from the impermeable portion  424  to the sidewall  220  or a distance that is smaller. Accordingly, the radial inner side of the rib may terminate prior to the impermeable portion  424  and/or the radial outer side of the rib  420  may terminate prior to the sidewall  220 . 
     Optionally, as exemplified, the impermeable portion  242  faces the rib  420 . It will be appreciated that only the portion of the outlet that faces the rib  420  need be air impermeable. Accordingly, the impermeable portion  244  may extends circumferentially at least 10°, at least 20°, or at least 30° from the location of the rib  420 . The impermeable portion  244  may lead the rib  420  (i.e., begins upstream of the rib) in a direction of cyclonic flow within the chamber by at least 1°, at least 2°, or at least 5°. 
     As exemplified, the rear end of the air treatment chamber  210  is located at the end wall on which the air treatment outlet  232  (vortex finder  238 ) is provided. This allows the pre-motor filter  330  to have a larger size in a direction transverse to the longitudinal axis (e.g., a larger diameter) than if the air treatment chamber  210  extended to a position rearward of the front end of the pre-motor filter  330 , which allows for the axial length of the surface cleaning apparatus  100  to be shortened. Alternately, the rear end of the air treatment chamber  210  may be rearward of the rear end of the vortex finder, in which case, the rear end of the rib  420  may extend rearward of the vortex finder to or towards the rear end of the air treatment chamber. 
     The rib  420  may extend in a generally axial direction. As exemplified, the rib  420  may be a planar body extending in a plane that is generally parallel to the air treatment longitudinal axis  218  (e.g., the cyclone axis of rotation). The rib  420  extends to a rib axially inner end  442 . As exemplified, the rib axially inner end  442  may be closer to the front end of the air treatment chamber  210  than the opposite end of the rib  420 . Optionally, as exemplified, the rib axially inner end  442  is curved. The curved end extends further into the air treatment chamber  210  on a radially outer side  444  of the rib  420  than on a radially inner side  446  of the rib  20 . As exemplified, the rib axially inner end  442  may include a rounded curve between a radially inner side  446  and an axially innermost edge  448 . 
     Optionally, the rib  420  has an axial length  450  of 4 mm to 50 mm, 8 mm to 25 mm, or, optionally, 12 mm to 18 mm. The outlet air impermeable portion  424  may have an axial length  452  of 0 mm to 50 mm, 0 mm to 25 mm, or, optionally, 0 mm to 15 mm. Optionally, the rib  420  has a radial height  454  that is equal to or a fraction of the radial distance  456  between the outlet air impermeable portion  424  and the chamber sidewall  220 . The rib  420  may have a height  454  of 0.1 to 1 times the radial distance  456 , 0.25 time to 0.75 times the radial distance  456 , or, preferably, 0.4 times to 0.6 times the radial distance  456 . However, it will be appreciated that the rib  420  may be provided in any suitable shape and size. 
     It will also be appreciated that the assembly  200  may include one or more ribs. Where the assembly  200  includes a plurality of discrete ribs, the ribs may be angularly spaced apart about the cyclone axis of rotation  218 . Additionally. or alternatively, the ribs may be angularly spaced apart about the air treatment outlet  232 . The ribs  420  may be evenly spaced apart, may be of the same or different sizes and may be provided on the same or different walls. 
     Air Inlet with a Side Opening 
     The following is a description of air inlet with a side opening that may be used by itself or in combination with one or more of the rib arrester, the variable area inlet downstream opening, the curved closure member, the axially moving closure member, the withdrawable closure member, the closure member moved by a driving member, the openable chamber first end, the axially moveable chamber end, moving using fluid pressure, positioning of the user interface, the filter removeable past the user interface, the radially-removeable post-motor filter, the nested filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     In accordance with this aspect, the air inlet  230  of an air treatment chamber, which may be a cyclone chamber, has a side opening. The air inlet may comprise an axial extending conduit, such as inlet conduit  170  which has an opening in the axial extending sidewall thereof. In such a case, the external conduit, when provided, may have a downstream end that terminates forward of (upstream of) the sidewall opening. Alternately, the side opening  474 ,  476  may be in external conduit sidewall  146  (see, e.g.,  FIG.  17   ). Accordingly, when the external conduit  140  is inserted into the dirty air inlet, the sidewall opening may open onto the air treatment chamber (e.g., there may be no internal conduit  170  or the internal conduit  170  may terminate forward of or upstream of the downstream end of the portion of the external conduit  140  with the sidewall opening). It will be appreciated that if an inlet conduit  170  with a sidewall opening is also provided with a sidewall opening of the external conduit sidewall  146 , then the sidewall opening of the external conduit sidewall  146  and the sidewall opening of the inlet conduit  170  are preferable aligned during use of the surface cleaning apparatus. 
     If a sidewall opening of the external conduit sidewall  146  is provided, then the external conduit  140  may have an inlet end wall  262  at a downstream end thereof. Such an end wall may close of the downstream end of the external conduit such that the sidewall opening(s) are the only air outlet. In such a case, the inlet end wall  262  may provide rigidity to the downstream end of the external conduit. 
     If the air flow conduit (external conduit  140  and/or internal conduit  170 ) has a closed end, e.g., inlet end wall  262  or external conduit end wall  270 , then part of the sidewall opening may comprise an air permeable section  460  (e.g., mesh may be provided to cover part of the sidewall opening). For example, two sidewall openings may be provided, which may be on opposed sides of the air flow conduit. In such a case, one of the sidewall openings may be provided with an air permeable section  460 . 
     If the air flow conduit (external conduit  140  and/or internal conduit  170 ) has an open end, then part or all of the sidewall opening may comprise an air permeable section  460 . One or more air permeable sections  460  may be provided upstream of the inlet downstream opening  258  in a sidewall of the inlet conduit  170 . 
     In any embodiment, the air permeable section  460  may extend to the downstream end of the air flow conduit (e.g., inlet end wall  262  if the air flow conduit has a closed downstream end) or may terminate upstream thereof. 
     The following is a discussion of an inlet conduit with a side opening wherein the external conduit terminates forward of the sidewall opening. It will be appreciated that the same features may be used with an external conduit with a sidewall opening. 
     If the inlet downstream opening  258  into the air treatment chamber is only through the sidewall, then the inlet downstream end  252  may include an inlet end wall  262 . The inlet sidewall  260  may extend along part or all of the inlet longitudinal axis and may optionally extend forwardly from the end wall  262 . 
     The inlet end wall  262  may extend across the inlet longitudinal axis  254  and may close off the downstream end of the inlet sidewall  260 . The inlet end wall  262  may optionally be planar, and may optionally extend generally perpendicular to the inlet longitudinal axis  254 . The inlet end wall  262  may be removeable from the inlet sidewall in some embodiments. 
     As exemplified in  FIG.  6   , the inlet upstream opening  256  may include or consist of the chamber inlet opening  234  (i.e., the upstream end of the conduit leading to the sidewall opening or provided at the upstream end of the sidewall opening) and the inlet downstream opening  258  may include or consist of an opening (e.g., a sidewall opening) in a projecting conduit sidewall  248  of the projecting conduit  240 . The inlet sidewall  260  may include or consist of the projecting conduit sidewall  248 , and the inlet end wall  262  may include or consist of a projecting conduit end wall  264  of the projecting conduit. 
     Alternately, as exemplified in  FIGS.  20 ,  22 , and  23   , the air treatment inlet  230  includes the external conduit  140  that is removably received in the projecting conduit  240 , and the diameter of the inlet upstream opening  256  is limited by the inner diameter of the external conduit  140 , while the inlet downstream opening is limited by the overlapping portions of downstream openings  474 ,  476  in the external conduit  140  and the projecting conduit  240 . 
     As exemplified in  FIGS.  20 ,  22 , and  23   , the inlet sidewall  260  may include the projecting conduit sidewall  248  and/or the external conduit sidewall  146 , and the inlet end wall  262  may include the projecting conduit end wall  264  and/or an external conduit end wall  270 . 
     The external conduit end wall  270  may be a removeable end wall or cap, although it will be appreciated that if the external conduit  140  is received in the projecting conduit  240  and the projecting conduit  240  includes the projecting conduit end wall  264 , the external conduit  140  may not require an end wall or end cap to direct airflow through sidewall openings and may not include an end wall or end cap closing the end of the external conduit sidewall  146 . However, the end cap  270  may provide greater structural strength to the downstream end of the external conduit  140 . In some embodiments, the external conduit  140  is made of metal. Optionally, the external conduit  140  is a thin-walled conduit. The external conduit sidewall  146  may be a thin wall formed of metal. The external conduit end cap  270  may support the end of the external conduit  140  in embodiments in which one or more openings  474 ,  476  are formed in the sidewall, particularly where the openings extend to the downstream end of the external conduit sidewall  146 . 
     It will also be appreciated that the inlet end wall  262  and/or inlet sidewall  260  may include an alternative member, such as a further body received within the external conduit  140  and/or the projecting conduit  240 , such as a moveable inlet member  280  as discussed further elsewhere herein. 
     Referring again to  FIGS.  5  and  6   , the projecting conduit  240  extends between a projecting conduit inlet end  266  and a projecting conduit outlet end  268 . The chamber inlet opening  234  is at the projecting conduit inlet end  266 . The chamber inlet opening  234  may be an opening in a chamber end wall, such as the chamber first end wall  222  as exemplified. The projecting conduit  240  also includes a projecting conduit outlet opening  282  at the projecting conduit outlet end  268 . 
     The air treatment inlet  230  may be a hooked inlet. As exemplified. the projecting conduit inlet opening  284  and the projecting conduit outlet opening  282  may extend in non-parallel planes to change the direction of air flow along the apparatus air flow path  160 . The air treatment inlet  230  may also be a tangential inlet for a cyclone. As exemplified, the projecting conduit outlet opening  282  may extend generally parallel to the air treatment member longitudinal axis  204  (e.g., a cyclone axis). The projecting conduit outlet opening  282  may extend in a plane that is generally parallel to the air treatment member longitudinal axis  204 . 
     in some embodiments, the air treatment inlet  230  has an effective air inlet length  290 , the effective air inlet length  290  being the axial length of the inlet downstream opening  258 . As exemplified, this may be the axial length of the projection conduit outlet opening  282  where the protection conduit outlet opening  282  defines the inlet downstream opening  258 . The effective air inlet length  290  may be between 10 mm and 100 mm, between  25  mm and  75  mm, or optionally, between 40 mm and 60 mm. The effective air inlet length  290  may be generally equal to the projecting length  242  when the projecting conduit outlet opening  282  extends the length of the projecting conduit, as exemplified in  FIG.  6   . 
     The air treatment chamber  210  may have a chamber axial length  292  that is between 1.5 times and 10 times the effective air inlet length  290 , between 2.5 times and 6 times the effective air inlet length  290 , or, optionally, between 3 times and 4 times the effective air inlet length  290 . The ratio between the effective air inlet length  290  and the chamber axial length  292  affects the number of turns that air is subject to as it passes through the air treatment chamber  210 . Optionally, the ratio is selected to provide at least 2, 2.5, 3 or more turns. As discussed further elsewhere herein, the ratio between the effective air inlet length  290  and the chamber axial length  292  may be variable. 
     As exemplified in  FIGS.  5  and  6   , the projecting conduit  240  may be a generally linear conduit with a projecting conduit longitudinal axis extending between the inlet and outlet ends. The projecting conduit  240  includes a projecting conduit sidewall  248  extending between the inlet and outlet ends. As exemplified, the projecting conduit  240  may include or consist of the inlet conduit outlet end  174 . 
     As exemplified, the air treatment inlet  230  may include a downstream portion of the inlet conduit  170 . The downstream portion of the inlet conduit  170  may form the projecting conduit  240 , as exemplified. As exemplified in  FIGS.  5  and  6   , the inlet conduit  170  may extend into the air treatment assembly  200 . The inlet conduit  170  may extend into the air treatment chamber  210  of the air treatment assembly  200 . Optionally, the air treatment inlet  230  (e.g., the downstream end of the inlet conduit  170 ) extends into the air treatment chamber  210  from an end thereof and along (e.g., against) the chamber sidewall  220 , as exemplified. 
     The inlet conduit  170  includes an inlet conduit sidewall  178  extending between the inlet conduit upstream end  172  and the inlet conduit downstream end  174 . As exemplified, the projecting conduit sidewall  248  may form an outlet end portion of the inlet conduit sidewall  178 . 
     The projecting conduit outlet opening  282  is provided at the inlet conduit downstream end  174 . As exemplified, the projecting conduit outlet opening  282  may be a port opening into the air treatment chamber  210 . As exemplified, the projecting conduit outlet opening  282  may be an unobstructed opening (e.g., not covered by a screen or other porous member). As exemplified, the projecting conduit outlet opening  282  may be located at a chamber inlet port  294  of the air treatment chamber  210 . 
     As discussed previously, if a sidewall opening is provided and an end wall is not provided, or if two sidewall openings are provided, whether or not an end wall is provided, then an air treatment chamber air inlet  230  may include an air permeable section  460   
     As exemplified in  FIGS.  14  to  16   , an air treatment chamber air inlet  230  includes an air permeable section  460  in addition to the inlet downstream opening  258 . The bulk of air is directed through the inlet downstream opening  258 , which is open and does not have a mesh material or the like and which may be referred to as the primary opening. A lesser volume of air is allowed to pass through the air permeable section  460 , e.g., from the air treatment inlet  230  into the air treatment chamber  210 . The inlet downstream opening  258  and the air permeable section  460  provide parallel routes. 
     The air permeable section  460  may comprise or consist of an opening  462  through the inlet sidewall  260  with a barrier  464  to reduce airflow therethrough. The barrier  464  is permeable to air (i.e., porous) thereby essentially partially closing the opening  462  while permitting air flow therethrough. The barrier  464  may encourage air flow through the inlet downstream opening  258 . As exemplified in  FIGS.  15  and  16   , the air permeable section  460  is a porous section. The air permeable section  460  includes a porous material  464  closing the opening  462  in the inlet sidewall  260 . In some embodiments, the porous material  464  is a mesh material. The mesh material may have a pore size of 20 mesh to 200 mesh, 40 mesh to 160 mesh, or, optionally, 80 mesh to 120 mesh. However. it will be appreciated that the porous material  464  may be any suitable porous material, such as foam or felt or a perforated wall. 
     The air permeable section  460  and the inlet downstream opening  258  each open into the free volume  470  of the air treatment chamber  210 . Upon exiting either of the air permeable section  460  or the inlet downstream opening  258 , the air enters the free volume  470  of the air treatment chamber  210 . The air permeable section  460  forms a secondary pathway between the air treatment inlet  230  and the air treatment chamber  210 . This secondary pathway results in a reduction of the power required for the motor  322  to produce a given air flow rate. 
     Optionally, this secondary pathway results in a reduction in the power requirement of between 0.5 Watts and 10 Watts, 1 Watt and 6 Watts, or 2 Watts and 4 Watts. 
     In the exemplified embodiment of  FIGS.  15  and  16   , the air treatment chamber air inlet  230  includes the projecting conduit  240  with the projecting conduit outlet opening  282  opening to the chamber inlet port  294  and a secondary opening  472  through which air may pass, and the inlet air permeable section  460  may include or consist of the secondary opening  472 . 
     As exemplified, the secondary opening  472  may be an opening in the projection conduit sidewall  248 . The secondary opening may have the same axial length as the outlet opening  282  or it may be longer or shorter. Alternately, or in addition, the secondary opening may be opposed to the outlet opening or it may be axially spaced from the projecting conduit outlet opening  282  by, e.g., a portion of the projecting conduit sidewall  248 . 
     Alternatively, as exemplified in  FIGS.  17  to  20   , the air treatment chamber air inlet  230  may include the external conduit  140 . It will be appreciated that air treatment chamber air inlet  230  may include the external conduit  140  without an integral projection conduit  240 , or, as exemplified, may include both the projection conduit  240  and the external conduit  140 . 
     As exemplified in  FIG.  20   , the inlet downstream opening  258  may be formed by overlapping openings of the external conduit  140  and the projecting conduit  240 . Similarly, the inlet air permeable portion may be formed by the overlapping openings of the external conduit  140  and the projecting conduit  240 . 
     As exemplified in  FIGS.  15  and  16   , the projection conduit  240  may include the projection conduit outlet opening  282  and the separate secondary opening  472 , while the external conduit  140  may include a first downstream opening  474  and a second downstream opening  476  separate from the first downstream opening  474  separated by a portion of the external conduit sidewall  146 . The first downstream opening  474  and the second downstream opening  476  of the external conduit  140  may be openings in the external conduit sidewall  146 , as exemplified. The air treatment inlet  230  may include the projection conduit  240  with the external conduit  140  received in the projection conduit  240  with the first downstream opening  474  aligned with the projection conduit outlet opening  282  and the second downstream opening  476  aligned with the secondary opening  472 . It will be appreciated that in embodiments in which the air permeable section  460  is a porous section and is formed by overlapping openings of multiple members, the porous material  464  may be included in only one of the multiple members. For example, the porous material  464  may extend across the second downstream opening  476  while the secondary opening  472  is unobstructed. 
     Optionally, the air permeable section  460  is opposed to the inlet downstream opening  258  across an interior passage of the air treatment inlet  230 . The air permeable section  460  may include a portion that is opposite (i.e., directly across from) the inlet downstream opening  258 , as exemplified. 
     The air permeable section  460  and/or the inlet downstream opening  258  may be provided upstream of the inlet end wall  262 . Optionally, the air permeable section  460  and/or the inlet downstream opening  258  is downstream of a wand or auxiliary cleaning tool. In some embodiments, the air permeable section  460  and/or the inlet downstream opening  258  have downstream ends that are located at the inlet end wall  262  (e.g., abutting the end wall). However, it will be appreciated that the air permeable section  460  and/or the inlet downstream opening  258  may be provided at any suitable location opening into the air treatment chamber  210 . 
     As exemplified in  FIGS.  21  to  23   , in embodiments in which the external conduit  140  is received in the projecting conduit  240 , the external conduit  140  and the projecting conduit  240  may each include an alignment member. The alignment members are provided to assist a user in inserting the external conduit  140  into the projecting conduit  240  in an appropriate orientation. Optionally, the alignment members  480 ,  482  are arranged to prevent the external conduit  140  from being inserted if misaligned. The projecting conduit alignment member  480  and the external conduit alignment member  482  may be coupled when the external conduit  140  is received in the projecting conduit  240  in a suitable position in which at least one opening of the external conduit  140  is aligned with at least one opening in the projecting conduit  240  to allow airflow therethrough. 
     Optionally, one of the projecting conduit alignment member  480  and the external conduit alignment member  482  is a male member and the other is a corresponding female member. For example, the male member may be a radial projection (e.g., a key), and the female member may be a corresponding channel. In some embodiments, the alignment members may be electrical connectors. The projecting conduit alignment member  480  may be a female electrical connector, and the external conduit alignment member  482  may be a male electrical connector. 
     Variable Area Inlet Downstream Opening 
     The following is a description of an inlet downstream opening  258  having a variable cross sectional area, which may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the curved closure member, the axially moving closure member, the withdrawable closure member, the closure member moved by a driving member, the openable chamber first end, the axially moveable chamber end, moving using fluid pressure, positioning of the user interface, the filter removeable past the user interface, the radially-removeable post-motor filter, the nested filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     In accordance with this aspect, as exemplified in  FIGS.  21  to  23   , the inlet downstream opening  258  of the air treatment inlet  230  has a variable cross sectional area. The inlet downstream opening  258  has a cross sectional area that is variable between a first cross sectional area and a second cross sectional area that is less than the first cross sectional area. The size of the cross sectional area of the inlet downstream opening  258  may be varied to change the separation characteristics of the surface cleaning apparatus  100 , such as to change backpressure or to change the ratio between the effective air inlet length  290  and the chamber axial length  292 . As discussed elsewhere herein, the ratio between the effective air inlet length  290  and the chamber axial length  292  affects the number of turns that air passing through the cyclone chamber is subject to, and so affects the efficiency of the surface cleaning apparatus  100 . 
     Accordingly, the first cross sectional area may have a first effective air inlet length and the second cross sectional area may have a second effective air inlet length that is less than the first effective air inlet length. Air flowing through a cyclone may have a greater number of turns in the cyclone chamber  210  when the inlet downstream opening  258  has the second, shorter effective air inlet length rather than the first effective air inlet length. 
     It will be appreciated that the cross sectional area of a sidewall inlet may be changed in any suitable way. In some embodiments, the air treatment inlet  230  is reconfigured by moving a moveable inlet member  280  of the air treatment inlet  230  to adjust the size of the cross sectional area (e.g., axial length) of the inlet downstream opening  258 . It will be appreciated that the cross sectional area of the inlet downstream opening  258  may vary as the moveable inlet member  280  moves. The moveable inlet member  280  may be moveable between a first member position in which the inlet downstream opening  258  has a first cross sectional area and a second member position in which the inlet downstream opening  258  has a second cross sectional area that is less than the first cross sectional area. 
     The moving member  280  may be any suitable member. For example, in embodiments in which the air treatment inlet  230  includes one conduit (e.g., external conduit  140 ) received within another (e.g., inlet conduit  170 ) with the inlet downstream opening  258  formed by overlapping sidewall openings of the conduits, one conduit may be the moveable inlet member  280  and may be adjusted within the other to change the size (e.g., axial length) of the inlet downstream opening  258 . 
     Alternatively, as exemplified in  FIGS.  21  to  23   , the moveable inlet member  280  may be a blocking member receivable within a conduit of the air treatment inlet  230 . The blocking member blocks off a portion of the conduit to force the air flow path  160  out of a sidewall outlet of a conduit upstream of the blocking member. For example, the blocking member may be an end wall  262 ,  270 . Alternately, it will be appreciated that the moveable inlet member  280  may be or include the closure member  310 , or the closure member  310  may include the moveable inlet member  280 . 
     The moveable inlet member  280  may be moveable from a first member position to a second member position. In the first position, the moveable inlet member  280  may block or partially block the downstream end of a conduit and in the second position, the moveable inlet member  280  may open or partially open the downstream end of a conduit. Accordingly, adjusting the position of the moveable inlet member  280  may adjust the amount of air exiting axially out of the downstream end of a conduit and the amount exiting through a sidewall opening of a conduit. Alternately, the first position may be upstream of the second position whereby, as the moveable inlet member  280  is moved from a second downstream position to a first upstream position, the length of a sidewall outlet is shortened. 
     It will be appreciated that the moveable inlet member  280  may be moveable in any suitable way. The movable member  280  may be moveable between a position in an air inlet conduit of the air treatment chamber and a position removed therefore. For example, the moveable member may move about a pivot axis or along a liner path (e.g., a radial path with respect to the air treatment member longitudinal axis) between a position received in the projecting conduit  240  and/or the external conduit  140  and a position removed from within the projecting conduit  240  and/or the external conduit  140 . Alternately, or in addition, the moveable inlet member  280  may be axially moveable parallel to the air treatment member longitudinal axis  204  and/or the inlet conduit axis  174 . The moveable inlet member  280  is moveable to a position at which it blocks off a portion of a sidewall opening that would otherwise be available to the air flow path  160  and may therefore be referred to as a blocking member. 
     The moveable inlet member  280  may form a terminal end  490  of the air treatment inlet  230  or of the external conduit  140  or of any conduit in which it is provided. 
     As exemplified in  FIGS.  21  to  23   , the inlet downstream opening  258  may extend to the moveable inlet member  280  when the moveable inlet member  280  is in it downstream position (see  FIG.  22   ). In this position, the moveable inlet member  280  forms an end wall of the air treatment inlet  230  at the outlet end thereof, and extends transverse to a flow direction of air through the upstream portion of the air treatment inlet  230 . As the moveable inlet member  280  moves to its upstream position, the length of the inlet downstream opening  258  is shortened whereby the effective air inlet length  290  of the inlet downstream opening  258  is varied. 
     The moveable inlet member may be part of the air treatment assembly and may be slideable receivable in the external conduit  140  when the external conduit  140  is inserted into the dirty air inlet. Accordingly, when the external conduit  140  is inserted into the dirty air inlet and the moveable member is at its axially inner (rearward) position, the moveable inlet member  280  may extend across the downstream end of the external conduit  140  to close off an internal passage of the external conduit  140  through which the air flow path  160  extends, effectively forming an end wall thereof. Alternately, the moveable inlet member  280  may be a moveable inlet end wall  262  of the external conduit  140  (e.g., a wand). Optionally, the moveable inlet member  280  may be part of the external conduit end cap  270  of the external conduit. As such, it may be removable with the external conduit from the surface cleaning apparatus. Alternately, if the external conduit  140  does not extend into the surface cleaning apparatus to the upstream (forward) position of the moveable member  280 , then the moveable member may move withing the inlet conduit  170 . 
     As exemplified in  FIGS.  24  to  26   , the moveable inlet member  280  may be received within the projecting conduit  240 . The moveable inlet member  280  may extend across the projecting conduit  240  to close off an internal passage of the projecting conduit  240  or a portion thereof through which the air flow path  160  extends. Accordingly, the moveable inlet member  280  may direct air that is traveling through the air flow path  160  to exit the projecting conduit  240  through a sidewall outlet that is located upstream of the moveable inlet member  280 . 
     In some embodiments, as exemplified in  FIGS.  24  and  25   , the moveable inlet member  280  may move along a moveable member track  492 . The track  492  may be or include, e.g., a rail. The moveable member track  492  may extend axially (i.e., parallel to the air treatment longitudinal axis  218 ). The moveable member track  492  may be fixed to, or built into, the chamber sidewall  220 , and may optionally extend only within the air treatment inlet  230 . The moveable member track  492  may be a linear rail, which may be provided in the inner side of the sidewall. 
     The cross sectional area may be changed automatically or manually, or the surface cleaning apparatus  100  may be configured such that both automatic and manual options are available. In embodiments in which the air treatment inlet  230  includes a moveable member  280 , the moveable inlet member  280  may be moved manually and/or automatically. For example, the moveable member may be moved by a manually moved mechanical link, air pressure or suction caused by the suction motor, and/or a further motor or a solenoid that is provided in addition to the suction motor, including any of the mechanisms described herein. 
     The moveable inlet member  280  may move in response to pressure changes within the surface cleaning apparatus  100 , such as within the air treatment inlet  230  and/or the free volume  470  of the air treatment chamber  210 . 
     Optionally, the moveable inlet member  280  moves to keep the pressure at a constant level. For example, if air pressure drops (due to dirt accumulating on a pre-motor filter or the screen of the vortex finder in a cyclone chamber), then the movable member  280  may move to increase the cross sectional area of the inlet downstream opening  258  thereby reducing the back pressure through the opening  258  and offsetting or partially offsetting the air pressure drop. This may assist in maintaining cyclonic flow as despite the pressure drop. 
     As exemplified in  FIGS.  25  and  26   , the moveable inlet member  280  may be manually moveable. Alternately, the moveable member may be automatically moved in response to a change of pressure or air flow through the surface cleaning apparatus. Accordingly, for example, one or more pressure or air flow sensors may be provided in the air flow path and upon issuance of a signal from one or more sensors, the position of the moveable member may be changed, e.g., by a solenoid or stepper motor. 
     An actuator  502  may be provided to control the movement of the moveable inlet member  280 . 
     As exemplified in  FIGS.  24  and  25   , the actuator  502  is a manually moveable toggle  500 , which may be on a surface of the main body  120 . For example, the manual toggle  500  may be a mechanical slider, as exemplified. The manual toggle  500  is provided to be manually manipulated (e.g., slid) by a user. The user may move the manual toggle  500  between a first toggle position ( FIG.  24   ) and a second toggle position ( FIG.  25   ). Moving the manual toggle  500  between the first toggle position and the second toggle position may move the moveable inlet member  280  between the first member position and the second member position. 
     The manual toggle  500  is drivingly coupled to the moveable inlet member  280  to move the moveable inlet member  280  between the first member position and the second member position 
     The manual toggle  500  may be mechanically linked directly to the moveable inlet member  280  such that moving the manual toggle  500  pushes and/or pulls the moveable inlet member  280 . In some embodiments, the when the manual toggle  500  is in the first toggle position the moveable inlet member  280  is in the first member position, and when the manual toggle  500  is in the second toggle position the moveable inlet member  280  is in the second member position. Accordingly, the manual toggle  500  may be a body that is directly secured to the moveable inlet member  280  as exemplified in  FIGS.  25  and  26    (e.g., molded as part thereof). 
     Alternatively, as exemplified in  FIGS.  27  and  28   , the manual toggle  500  may be mechanically drivingly coupled to the moveable inlet member  280  via mechanical coupling  504 . Manual toggle  500  may therefore be an actuator  502  that may be a body that is directly secured to a mechanical linkage  504  that is directly secured to the moveable inlet member  280 . 
     Alternately, an actuator  502  which actuates an electromechanical member, such as a motor (e.g., a stepper motor) or a solenoid may be provided to move the moveable inlet member  280  between the first member position and the second member position. Such an actuator, which may be referred to as a powered actuator may be coupled to a power supply of the surface cleaning apparatus (e.g., a battery). A powered actuator may be communicatively coupled to the control system to be controlled thereby. 
     Alternately, the actuator  502  may be an unpowered actuator such as, e.g., an aneroid capsule responsive to pressure changes. The moveable member actuator  502  may be controlled in any suitable way, such as by the manual toggle or automatically by signals generated by the control system  370  of the surface cleaning apparatus (e.g., in response to changes in pressure, changes in sensor values, or changes in operational modes). 
     The moveable member actuator  502  may optionally be a dedicated actuator for controlling only the moveable inlet member  280 . Any actuator discussed herein may be used. 
     Alternatively, moveable member actuator  502  may control another function of the surface cleaning apparatus  100  in addition to the moveable inlet member  280 . For example, the actuator  502  may be provided to control another setting of the surface cleaning apparatus  100  (i.e., presented to the user as being for the control of the other setting). For example, the actuator  502  may be a cleaning mode setting toggle (e.g., selecting between an above floor cleaning mode and a floor cleaning mode), and actuating the actuator  502  may select a mode of the surface cleaning apparatus  100 , and the moveable inlet member  280  may be adjusted to compliment the selected mode, as disused further elsewhere herein. In such a case, the surface cleaning apparatus  100  may not include any indicia indicating that the actuator  502  controls the moveable inlet member  280 . 
     Alternatively, or additionally (e.g., indirectly, as discussed further elsewhere herein), the cross-sectional area of the inlet downstream opening  258  may be automatically varied based upon an air flow rate of air in the air flow path  160 . When the air flow rate is a first flow rate, the inlet downstream opening  258  has a first cross-sectional area and when the air flow rate is a second flow rate that is lower than the first flow rate, the inlet downstream opening  258  has a second cross-sectional area that is different from the first cross-sectional area and may be smaller. The air flow rate may vary the cross-sectional area directly and/or indirectly. 
     The air flow rate may vary the cross sectional area directly, as the force of air impinging the moveable inlet member  280  may cause a change in the positioning of the moveable inlet member  280 . The moveable member may be biased to an upstream (forward) position. In such a case, if the first air flow rate is higher than the second air flow rate, then air impinging the moveable inlet member  280  at the first air flow rate (i.e., the higher air flow rate) may carry greater force and so moves the moveable inlet member  280  farther downstream (rearwardly) than air impinging the moveable inlet member  280  at the second air flow rate. Moving the moveable inlet member  280  farther downstream increases the axial length of the inlet downstream opening  258  and thereby enables a higher airflow into the air treatment member. Accordingly, the force of air may move the moveable inlet member  280  automatically to increase the axial length of the opening  258  and the biasing member (e.g., a spring) may move the moveable member to reduce the axial length of the opening  258  when the air flow rate decreases, all without user intervention. 
     As exemplified in  FIGS.  29  and  30   , the surface cleaning apparatus  100  may include a biasing member  506  (e.g., a spring or compressible balloon) biasing the movable member  280  to a position that results in a smaller cross sectional area of the inlet downstream opening  258 . The moveable inlet member  280  may be biased towards the second member position ( FIG.  30   ) by the biasing member  506 , and the force of air impinging the moveable inlet member  280  may overcome the force of the biasing member  506  to move the moveable inlet member  280  all or part of the way to the first member position ( FIG.  29   ). 
     Alternatively, or additionally, the cross sectional area of the inlet downstream opening  258  may vary automatically as the surface cleaning apparatus is reconfigured wherein the reconfiguration results in a change in the air flow rate. The change in air flow rate may be due to a change in power level provided to the suction motor and, accordingly, each of the air flow rate and the cross sectional area of the inlet downstream opening  258  may respond to a common input (e.g., a change in power level). Accordingly, the cross sectional area of the inlet downstream opening  258  and the air flow rate both respond to the same user action, such as a user activating a toggle, such as pushing a soft button (touch screen) or a hard button or moving a slider to change an operating mode of the surface cleaning apparatus (e.g., changing from a low flow mode to a high flow mode), or reconfiguring the surface cleaning apparatus  100 , such as mounting a portable unit to a floor cleaning unit  154  to form, e.g., a stick vacuum. 
     For example, the surface cleaning apparatus  100  is removably mountable to the floor cleaning unit  154  whereby, when the surface cleaning apparatus  100  is mounted to the floor cleaning unit  154  the surface cleaning apparatus is operable in an upright vacuum cleaner mode and, when the portable cleaning unit is removed from the floor cleaning unit  154 , the portable cleaning unit is operable in an above floor (hand vac) cleaning mode. The above floor vacuum cleaner mode may comprise the first air flow rate, e.g., as a result of a first power level being supplied to the suction motor  322 . The upright vacuum cleaning mode may comprise the second air flow rate that is lower than the first air flow rate, e.g., as a result of a second power level being supplied to the suction motor  322  that is less than the first power level. The above floor cleaning mode may be a high-power mode and the upright cleaning mode may be a low-power mode, wherein a low power mode may allow for a longer run time. If the power level of the suction motor  322  is automatically varied as an operating mode of the surface cleaning apparatus  100  is changed from the upright vacuum cleaner mode to the above floor cleaning mode, then the cross-section area of the air treatment inlet  230  may also be automatically varied as an operating mode of the surface cleaning apparatus is changed from the upright vacuum cleaner mode to the above floor cleaning mode. 
     This change in the cross-sectional area may be due to the change in air flow as discussed previously. Alternately, the change may be due to the moveable member being moved by the insertion of the external conduit  140  driving the moveable member  280  to the upright vacuum cleaner mode and the moveable member returning to the hand vac cleaning mode when the external conduit  140  is removed. The external conduit may be driving connected to the moveable member upon insertion and a biasing member may return the moveable member to the hand vac cleaning mode upon withdrawal of the external conduit. Alternately, the change may be due to an electromechanical member moving the moveable member in response to mounting and removing the surface cleaning apparatus from the floor cleaning unit (e.g., insertion and/or removal of the external conduit). 
     A lower power mode may result in a lower air flow rate which may result in a lower cyclone efficiency. The moveable inlet member  280  may be moved to decrease the axial length of a cyclone inlet to thereby to increase the number of turns of the air flow path  160  within the cyclone chamber  210 . The moveable inlet member  280  may be moved by any method discussed herein in response to the mode change or in response to the same user command that caused the mode change. 
     Alternately, or in addition, the cross-sectional area of the inlet downstream opening  258  may be varied based on dirt characteristics in the surface cleaning apparatus. The dirt characteristics may be one or more of the size (i.e., particle size) of dirt which is collected, the size of dirt that is expected to be collected (e.g., based on a mode selection), the size of dirt that is carried by an air flow path  160  downstream of a selected component  510  of the surface cleaning apparatus, and the dirt loading of an air flow path downstream of the selected component  510  of the surface cleaning apparatus  100 . It will be appreciated that the selected component  510  referred to above may be the inlet conduit  170 , a dirt separating component such as the air treatment chamber  210 , the air treatment assembly  200  as a whole, or the pre-motor filter  330 . The cross sectional area of the inlet downstream opening  258  may be varied (e.g., the effective air inlet length  290  varied) to change (i.e., increase or decrease) the efficiency of the air treatment chamber  210 . For example, the effective air inlet length  290  may be reduced to produce more turns in a cyclone chamber and to thereby remove finer dirt from the air flow path  160 . 
     For example, when dirt having a first size is collected the inlet downstream opening  258  may have the first cross-sectional area, and when dirt having a second size that is smaller than the first size is collected the inlet downstream opening  258  may have the second cross-sectional area. Alternately or in addition, when air downstream of the selected component  510  has a first dirt loading the inlet downstream opening  258  may have the first cross-sectional area, and when air downstream of the inlet downstream opening  258  has a second dirt loading that is higher than the first dirt loading the inlet downstream opening  258  may have the second cross-sectional area. 
     It will be appreciated that dirt particle size or dirt loading may be determined in any suitable way, such as via a dirt sensor  512 , as exemplified in  FIGS.  27  and  28   , or via user observation. In some embodiments, the dirt sensor  512  is operable to detect a size of dirt in an air flow path  160  and/or the dirt collection region  300 . A dirt sensor  512  that is operable to detect a size of dirt in the air flow path  160  may be referred to as a dirt size sensor. The dirt sensor  512  may determine an average, mean, or minimum particle size of detected particles, and may base its output on that value. Alternatively, or additionally, in some embodiments the dirt sensor  512  is operable to detect a dirt loading of an airstream. A dirt sensor  512  that is operable to detect dirt loading of an air stream may be referred to as a dirt loading sensor. The dirt sensor  512  may determine a proportional volume of dirt in the air stream, and base its output on that value. 
     It will be appreciated that the dirt sensor  512  may be any suitable sensor. In some embodiments, the dirt sensor  512  is an acoustic sensor (e.g., a microphone). For example, the output of the acoustic sensor may be used to gauge particle size. In some embodiments, the dirt sensor  512  is an optical sensor. In some embodiments, the dirt sensor  512  is a laser sensor. 
     The dirt sensor  512  may be located at any suitable location of the surface cleaning apparatus  100 . In some embodiments, the surface cleaning apparatus  100  includes a dirt sensor  512  in, or arranged to detect dirt in (i.e., directed towards), the air treatment chamber, the dirt collection region  300  and/or in a dirt outlet between the dirt collection region  300  and an air treatment chamber  210 . In some embodiments, the surface cleaning apparatus  100  includes a dirt sensor  512  in the air flow path  160  (e.g., in the inlet  170 ) or arranged to detect dirt travelling towards the air flow path  160  (e.g., in the external conduit  140 ). 
     In embodiments in which a dirt sensor  512  is in, or arranged to detect dirt in, the air flow path  160 , it will be appreciated that the dirt sensor may be in, or arranged to detect dirt in, any suitable location. That location may be within (e.g., as exemplified by sensor  512   a,  see  FIG.  28   ) or downstream of the air treatment outlet  232 , such as within or downstream of the vortex finder  238 ). That location may be at the air treatment chamber outlet end  216  upstream of the air treatment outlet  232 , or upstream of the pre-motor filter  330  (e.g., within the pre-motor filter housing  334  upstream of the pre-motor filter  330 , as exemplified by sensor  512   b ). That location may be upstream of the air treatment chamber, as exemplified by sensor  512   c.  In some embodiments, that location is downstream of the free volume  470  of the air treatment chamber  210 , downstream of the air treatment assembly  200  as a whole, and/or downstream of the pre-motor filter  330 , to detect changes in the size of dirt particles that are making it past these dirt separation components. It will be appreciated that any suitable number of dirt sensors may be used, and their outputs may be used in any suitable way, e.g., to send a signal which may be sent to a controller which in turns sends a signal to actuate an electromechanical member. 
     A user may manually change the position of the moveable inlet member  280  due to changing dirt characteristics. For example, the surface cleaning apparatus  100  may generate an alert to prompt a user to adjust the position of the moveable inlet member  280  based upon a dirt characteristic that is determined. The alert may be, e.g., an audible alert played by a speaker of the apparatus, or a visual alert displayed on the apparatus (e.g., a flashing light or an illuminated icon). In use, the user may respond to the alert by using actuator  502  to move the moveable inlet member  280 . 
     The alert may be generated in response to detecting a change in the size of dirt that is being collected or the size or amount of dirt that is travelling downstream of the air treatment chamber and/or the air treatment assembly. In some embodiments, the alert is generated in response to the output of the dirt sensor  512 . Alternatively, or additionally, the alert may be generated in response to a user action indicative that the surface cleaning apparatus  100  is being or will be used to collect dirt of a different size, such as switching a mode of operation (e.g., above floor vs. upright) or adding an attachment. 
     Alternatively or in addition, the cross-sectional area of the inlet downstream opening  258  may be automatically varied due to changing dirt characteristics. The variation may be in response to an output of a dirt sensor  512  or in response to a user action indicative that the surface cleaning apparatus  100  is being or will be used to collect dirt of a different size or to a reconfiguration of the surface cleaning apparatus to a different cleaning mode. The moveable member actuator  502  may move the moveable inlet member  280  in response to an output from the dirt sensor  512  indicative of a change in the dirt characteristics (e.g., particle size or dirt loading of an air flow stream), or in response to a user mode selection or accessory attachment. For example, when an output of the dirt sensor  512  is indicative of finer dirt being detected, the moveable member actuator  502  may move the movable member  280  to shorten the effective air input length  290 . 
     While in some embodiments the cross sectional area of the inlet downstream opening  258  changes in response to changes in the surface cleaning apparatus&#39; operational mode, it will be appreciated that in some embodiments the cross sectional area of the inlet downstream opening  258  may also vary within a single mode. For example, the cross sectional area of the inlet downstream opening  258  may vary during an upright mode if there is a change in dirt characteristics (e.g., a sensed change in dirt loading of an air stream). Similarly, the cross sectional area of the inlet downstream opening  258  may change during an above floor cleaning mode if there is a change in dirt characteristics (e.g., a sensed change in particle size). 
     Curved Closure Member 
     The following is a description of a closure member  310  which is curved, which may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the variable area inlet downstream opening, the axially moving closure member, the withdrawable closure member, the closure member moved by a driving member, the operable chamber first end, the axially moveable chamber end, moving using fluid pressure, positioning of the user interface, the filter removeable past the user interface, the radially-removeable post-motor filter, the nested filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     in accordance with this aspect, as exemplified in  FIGS.  7  to  10 ,  31  and  32   , the closure member  310  is curved along at least one dimension with respect to a coordinate system defined by the apparatus longitudinal axis  110 , the apparatus vertical axis  112 , and the apparatus transverse axis  114 . The closure member may therefore be referred to as a curved member. Optionally, the closure member  310  is curved with respect only to a single dimension, as exemplified. In other words, the closure member  310  may be arcuate in shape. 
     The closure member  310  may have a curved surface  520  which, in the closed position, curves in at least one plane of a set of axial planes, wherein the set of axial planes are each defined by any two of the apparatus longitudinal axis  110 , the apparatus vertical axis  112 , and the apparatus transverse axis  114  extending therein. As exemplified in  FIGS.  9  and  10   , the curved surface  520  in the closed position may curve in a first plane  522  of the set of axial planes in which the apparatus vertical axis  112  and the apparatus transverse axis  114  extend. As exemplified in  FIGS.  7  and  8   , the curved surface  520  in the closed position may curve in a second plane  524  of the set of axial planes in which the apparatus longitudinal axis  110  and the apparatus vertical axis  112  extend. It will be appreciated that the curved surface may also or alternatively curve in a third axial plane of the set of axial planes in which the apparatus longitudinal axis  110  and the apparatus transverse axis  114  extend. 
     As exemplified in  FIG.  33   , the closure member  310  may be curved in a selected plane  526  that is transverse to the axial direction (i.e., transverse to the apparatus longitudinal axis). The selected plane  526  may optionally be perpendicular to the apparatus longitudinal axis, as exemplified. As exemplified, the inlet sidewall  260  may be curved in the same selected plane  526 . Optionally, the inlet sidewall  260  and the closure member  310  each have a surface with a generally common curvature in the selected plane  526 . As exemplified in  FIGS.  31  to  33   , the closure member  310  in the open position may have a closure profile  530  in a plane that is transverse to the apparatus longitudinal axis (e.g., selected plane  526 ) that is similar to a sidewall profile  532  of the inlet sidewall  260  in the same plane. The closure member  310  may move longitudinally (i.e., generally parallel to the apparatus longitudinal axis  110 ) from an open position in which it is in the nozzle or within the air treatment inlet, to a closed position in which it closes the inlet downstream opening  258  in the inlet sidewall  260  of the air treatment inlet  230 . Alternatively, as exemplified in  FIGS.  9  and  10   , the closure member  310  may pivot down to the inlet sidewall  260  about an axis that extends generally parallel to the inlet sidewall  260 . 
     Optionally, at least one dimension of the curved surface  520  is linear with respect to the apparatus longitudinal axis  110 , the apparatus vertical axis  112 , and the apparatus transverse axis  114 . In other words, the closure surface may be arcuate in shape. Optionally, the curved surface  520  curves in only one plane of the set of axial planes when the closure member  310  is in the closed position. In other words, the curved surface  520  extends generally parallel to at least one of the set of axial planes. 
     In embodiments in which the surface cleaning apparatus  100  includes a closure seat  312 , the closure seat  312  may be a curved seat. The curved surface  520  may seat against (i.e., touch at each point along the closure perimeter  534 ) the curved closure seat  312  when the closure member  310  is in the closed position. The closure seat  312  may have a curvature that matches the curvature of the curved surface  520 . 
     As exemplified, the closure member  310  may be a thin body, such as a curved plate. The closure member  310  may have a first face  536  and an opposite second face  538 . The first face  536  and the second face  538  may extend generally parallel to one another, and may be of generally the same size and/or shape. The curved surface face  520  may be first face  536  or the second face  538 . 
     Optionally, the closure member  310  is shaped to match a shape of a component or opening of the air treatment inlet  230 . The closure member  310  may be shaped to match the shape of the inlet upstream opening  256  or the inlet downstream opening  258 . As exemplified in  FIGS.  7  and  8   , the inlet upstream opening  256  may be a circular shape curved along one dimension. The closure member  310  may be a curved and/or circular shape. As exemplified in  FIGS.  9  and  10   , the inlet downstream opening  258  may be a rectangular shape curved along one dimension (e.g., along a dimension parallel to the apparatus vertical axis  112 , as exemplified). The closure member  310  may be a rectangular shape and/or curved along one dimension. 
     The closure member  310  may pivot about a closure axis of rotation  540  between an open position ( FIG.  7   ) and a closed position ( FIG.  8   ). The closure member  310  may be pivotally coupled to a further body of the surface cleaning apparatus  100  by a closure pivot joint  542 . The closure axis of rotation  540  may extend in any suitable direction. Optionally, the closure axis of rotation  540  is generally parallel to one of the apparatus longitudinal axis  110 , the air treatment longitudinal axis  218 , the apparatus transverse axis  114 , or the apparatus vertical axis  112 . Optionally, the closure axis of  540  is generally perpendicular to one of the apparatus longitudinal axis  110 , the air treatment longitudinal axis  218 , the apparatus transverse axis  114 , or the apparatus vertical axis  112 . When closed, the closure member may extend generally perpendicular to the direction of air flow through the portion of the air flow path that the closure member closes when in the closed position. 
     As exemplified, the curved closure member may close an opening that is directed generally parallel to the conduit axis  254  or an opening in the inlet sidewall  260 . Optionally, as exemplified in  FIGS.  9  and  10   , the curved closure member  310  pivots down over an opening in the inlet sidewall  260 . 
     As discussed subsequently, it will be appreciated that the closure member  310  may be external to the air flow path  160  when in the closed position. For example, the closure member  310  may rotate or translate into a pocket that is located exterior to the air flow path (e.g., a pocket provided on an exterior surface of the inlet conduit  170 ). The pocket may have a port that opens onto the, e.g., inlet conduit  170 . When received in the pocket, the closure member may close the port and, optionally, form part of the surface of the air flow path (e.g., part of the inlet conduit  170 ) to thereby provide a smooth continuous surface of the air flow path. 
     Axially Moving Closure Member 
     The following is a description of a closure member  310  that is axially moveable, which may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the variable area inlet downstream opening, the curved closure member, the withdrawable closure member, the closure member moved by a driving member, the operable chamber first end, the axially moveable chamber end, moving using fluid pressure, the user interface on the handle, the user interface overlying the main body housing, the user interface on an annular portion, the filter removeable past the user interface, the radially-removeable post-motor filter, the nested filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     In accordance with this aspect, as exemplified in  FIGS.  34  to  39   , the closure member  310  moves axially with respect to the air treatment member longitudinal axis  204  and/or the inlet conduit axis  254  between a closed position ( FIG.  39   ) and/or a partially closed position ( FIG.  35   ) and an open position ( FIG.  34   ). When the closure member is in the open position, during operation of the surface cleaning apparatus, air flows through the air treatment inlet  230  to the air treatment chamber  210 . When the closure member  310  is in the closed position, air flow through the air treatment inlet  230  is inhibited. In the closed position, closure member may inhibit or prevent dirt exiting the surface cleaning apparatus when the suction motor is deenergized and, e.g., the dirty air inlet points downwardly. 
     When the closure member  310  is in the open position, airflow through the air flow path  160  may have a flow direction  550  at the location at which the closure member  310  is positioned when in the closed position (e.g., the position exemplified in  FIG.  38   ), and the closure member  310  may be moveable generally parallel to that flow direction  550  between the open and closed positions. The flow direction  550  may be axial with respect to the air treatment member longitudinal axis  204  and/or the inlet conduit axis  176 . The air treatment member  202  may have a first end and a second end, wherein the second end is spaced apart from the first end in the flow direction  550 . The flow direction  550  may be rearward. When the closure member  310  moves to the open position, the closure member moves axially in the flow direction and when the closure member  310  moves to the closed position, the closure member moves opposite to the flow direction  550  from the open position through the inlet conduit  170 , towards the inlet upstream end  250  of the air treatment inlet  230  to the closed position. 
     Optionally, in the closed position, the closure member abuts and end wall of port in the air flow path. For example, the upstream end of the inlet conduit  170  may have an inlet port and, in the closed position, the closure member  310  abuts the inlet port of the inlet conduit  170  or the upstream end of the air treatment inlet  230  may have an inlet port (i.e., the chamber inlet opening  234 ), and, in the closed position, the closure member  310  abuts the inlet port of the air treatment inlet  230 . 
     It will be appreciated that the closure member  310  may have any suitable shape. The closure member  310  may be, e.g., circular, oval, or square, and may be, e.g., planar or curved. Optionally, the closure member  310  is shaped to match a shape of a component or opening of the air treatment inlet  230  that is to be closed. Accordingly, for example, the closure member  310  may be shaped to match the shape of the inlet upstream opening  256  or the inlet downstream opening  258 . If the inlet upstream opening  256  is planar or circular in shape, then the closure member  310  may be planar and/or circular in shape. The inlet downstream opening  258  may be a rectangular shape curved along one dimension (e.g., along a dimension parallel to the apparatus vertical axis  112 , as exemplified) in which case the closure member  310  may be a rectangular shape and/or curved along one dimension. The closure member  310  may cover a cross sectional area that is equal to a cross sectional area of the inlet upstream opening  256  and/or the inlet downstream opening  258  if the closure member is to seat in the opening or larger if the closure member is to overlie the opening when in the closed position. 
     It will be appreciated that t the closure member  310  may be the inlet end wall  262 . Alternatively, as exemplified in  FIGS.  31  and  32   , the closure member  310  may extend generally parallel to the flow direction  550 . 
     As exemplified in  FIGS.  31  and  32   , the closure member  310  may close a tangential inlet to the air treatment chamber  210  (i.e., as opposed to a transversely extending opening). The closure member  310  may be axially moveable to a position in which it extends across (Le., closes) a sidewall opening  258 . As exemplified in  FIG.  32    in the closed position the closure member may close the air treatment downstream opening  258 . In the open position, the closure member  310  may be received against a wall of the air treatment member  202 , extending across the wall (e.g., the inlet sidewall  260 ) and may therefore overly the sidewall. The closure member may have the shape of an annulus sector. The closure member  310  may move generally along the wall of the air treatment member  202  between (i.e., translating between) the closed and open positions. In some embodiments, an axially extending surface of the closure member  310  along a longest dimension of the closure member  310  faces an axially extending surface of the air treatment member  202  that has the outlet  258  so as to overlie the outlet  258  when in the closed position, and, optionally, the closure member  310  moves generally parallel to the axially extending surface of the air treatment member between the closed and open positions. In some embodiments, the closure member  310  moves rearwardly and/or in the flow direction  550  from the open position to the closed position. 
     It will be appreciated that the closure member  310  may be moved in any suitable way. The closure member  310  may be moved manually or automatically. The closure member  310  may be moved, e.g., by air pressure or suction generated by the suction motor or by any of the driving members discussed elsewhere herein. The closure member may be moved by being pushed back by an upstream end of the external conduit  140  when the external conduit  140  is inserted into the nozzle  180 , by an actuator of the surface cleaning apparatus  100  other than the suction motor, or by a manual sider or other manual toggle accessible to the user from outside the surface cleaning apparatus as discussed previously. 
     In some embodiments, the closure member  310  moves along a closure member track  560  which may include a rail. The closure member track  560  may be a linear track. The closure member track  560  may extend only within the air treatment inlet  230 , or may extend beyond the air treatment inlet  230  (e.g., into a free volume of the air treatment chamber  210  or elsewhere). Optionally, the closure member  310  moves longitudinally on a rail to the inlet end of the inlet conduit  170  to close the inlet conduit  170 . 
     Withdrawable Closure Member 
     The following is a description of a closure member  310  that can be withdrawn from the air flow path. The closure member  310  may be at least partially moveable to close a port or into or through a recess or passage formed in a wall or by a plurality of walls of the air treatment member  202 . This aspect may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the variable area inlet downstream opening, the curved closure member, the axially moving closure member, the closure member moved by a driving member, the openable chamber first end, the axially moveable chamber end, moving using fluid pressure, positioning of the user interface, the filter removeable past the user interface, the radially-removeable post-motor filter, the nested filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     It will be appreciated the closure member  310  may be provided in any portion of the air flow path, optionally upstream of the air treatment assembly  200 . 
     In accordance with this aspect, as exemplified in  FIGS.  40  to  56   , the air treatment assembly  200  has an assembly free volume  570  that includes the chamber free volume  470  of the air treatment chamber  210  and an inlet free volume  572  of the air treatment inlet  230 . The chamber free volume is an open space within the air treatment chamber  210  outside the air treatment inlet  230  and the air treatment outlet  232 . The inlet free volume  572  is an open space within the air treatment inlet  230  and that is part of the air flow path  160  when the closure member  310  is in the closed position. 
     In the open position, the closure member  310  may be at least partially removed from the assembly free volume  570  or fully removed from the assembly free volume  570 . This aspect reduces the extent to which the closure member  310  inhibits air flow when in the open position and/or reduces turbulence caused by a significant discontinuity in the transverse cross sectional area of the air treatment inlet  230  at a downstream edge of the closure member  310  when the closure member  310  is in the open position. 
     Optionally, when in the open position, the closure member  310  may be at least partially moved into or through a closure passage  574  (as exemplified in  FIGS.  40  and  41   ) and may be at least partially or fully received in a closure recess (e.g., pocket  580 , exemplified in  FIGS.  42  and  43   ) or it may be moved to close a port in a wall of the air flow path  160  (as exemplified in  FIGS.  53  and  54   ). Optionally, the closure member  310  in the open position is fully received in the closure recess or fully moved into or through the closure passage  574  or moved to close a port and form a smooth wall section at the location of the port. It will be appreciated that the closure passage may be similar to the closure recess, but extending all the way through the wall or walls to an exterior of the air treatment assembly  200  (and, optionally, to an exterior of the surface cleaning apparatus  100 ) such that the closure member  310  may be fully withdrawn from the air treatment assembly  200  through the closure passage. 
     The closure recess may be formed in a single wall, e.g., a recess in a smooth and continuous surface which surface optionally continues a significant portion of the way around the recess (e.g., at least 50%, 75% or 90% of a perimeter of the recess). The closure recess may be formed between walls. The closure recess has a mouth or port which opens into the air flow path, such as into the chamber free volume  470  or into the inlet free volume  572 . The recess may be exterior to the assembly free volume. 
     As exemplified in  FIGS.  51  and  52   , the closure recess, also referred to as a closure member pocket  580 , may be formed in a sidewall (as exemplified in  FIGS.  42  to  54   ) or end wall (as exemplified in  FIGS.  55  and  56   ) of the air treatment member  202 . In some embodiments, the closure member pocket  580  is formed in one and only one wall. Optionally, the closure member pocket is formed in the chamber sidewall  220 , the inlet sidewall  260 , the inlet conduit sidewall  178  (e.g., including the nozzle  180 , as exemplified in  FIGS.  42  and  43   ), and/or the inlet end wall  262 . Optionally, the closure member pocket  580  is formed in an axially extending sidewall (i.e., extending generally parallel to the apparatus longitudinal axis  218 ). However, as exemplified in  FIGS.  53  and  54   , it will be appreciated that the closure member pocket  580  may alternatively be formed in a sidewall  260  that does not extend axially. 
     As exemplified in  FIG.  52   , the closure member  310  may be at least partially withdrawn into a closure member pocket  580  formed in the inlet end wall  262 . The pocket  580  may be located further in the flow direction  550  (e.g., rearward) from the dirty air inlet  162  than the inlet downstream opening  258 , as exemplified. Alternatively, the inlet downstream opening  258  may be further in the flow direction (e.g., rearward) from the dirty air inlet  162  than the closure member pocket  580 . The closure member pocket  580  may be formed in a wall of the inlet conduit  170  and/or nozzle  180 . 
     Optionally, the closure member  310  is withdrawn into a sidewall of a generally smooth-walled bore. The smooth-walled bore is optionally a generally linear bore. As exemplified in  FIGS.  42  to  43   , the inlet sidewall  260  and/or inlet conduit sidewall  178  forms a generally smooth-walled bore  568  and the closure member pocket  580  or passage  574  is formed in the inlet sidewall  260  or inlet conduit sidewall  178  such that at least a portion of the closure member  310  may be withdrawn into the sidewall. 
     As exemplified in  FIGS.  44  and  45   , the closure member  310  may pivot about the pivot axis to rotate upwards into the pocket  580  and downward to cover an opening of the inlet  230  (e.g., the inlet upstream opening  256 , as exemplified). As exemplified in  FIGS.  42  and  43   , the inlet conduit sidewall  178  may form the generally smooth-walled bore  568 , and the closure member pocket  580  may be formed in the inlet conduit sidewall  178  such that at least a portion of the closure member  310  may be withdrawn into the inlet conduit sidewall  178 . As exemplified in  FIGS.  42  and  43   , the nozzle  180  may have a closure member pocket  580  formed in a wall therein (e.g., in a sidewall thereof) such that at least a portion of the closure member  310  may be withdrawn into the nozzle wall. Although it will be appreciated that the pocket  580  may alternately be formed in a sidewall of the inlet  230  (e.g., a portion of the inlet conduit sidewall  178  that extends into the air treatment chamber). It will also be appreciated that, when in the closed position, the closure member  310  may form part of the smooth-walled bore  568  and may be continuous part thereof. 
     As exemplified, the closure member pocket  580  may include at least a portion that is exterior to the assembly free volume  570 . The closure member pocket  580  may extend outward from the assembly free volume  570 . Optionally, the pocket may have a depth such that when in the closed position, the closure member may abut an inner surface of the wall defining the pocket  580  and may be flush with the smooth-walled bore  568 . 
     At least a portion of the closure member  310  in the closed position may be positioned in the assembly free volume  570  or the air treatment inlet  230 . Optionally, substantially all or all of the closure member  310  in the closed position is positioned in the air treatment inlet  230  in the closed position. 
     As discussed previously, in the open position, the closure member  310  may merge with a wall of the air treatment assembly  200 . In other words, as exemplified in  FIGS.  53  and  54   , a face  590  of the closure member  310  in the open position, which may be directed towards the air flow path  160 , may extend in a common surface with an abutting wall face  592  of an abutting wall  594  which is also directed towards the air flow path  160 , the common surface having a constant curvature along a line  596  extending across the face  590  and the abutting wall face  592  (and, optionally, a constant curvature along another line crossing the first line at a  90  degree angle). Where the closure member  310  in the open member position merges with a wall of the air flow path, such as a wall of the air treatment assembly  200 , the closure member  310  in the open member position may be referred to as forming a portion of the wall of the air flow path, such as a wall of the air treatment assembly  200 . 
     As exemplified, the closure member pocket  580  may have a mouth or pocket port  600  by which the closure member pocket  580  is open to the assembly free volume  570 . The closure member  310  may close the pocket port  600  when the closure member is in the open member position. Accordingly, when the closure member  310  closes the pocket port  600  and is flush with the surrounding surface, the closure member  310  may be referred to as having merged with the surrounding wall of the air treatment assembly  200 , and may be referred to as forming a portion of a smooth wall of the air treatment assembly  200 . Optionally, the pocket port  600  is in an axially extending sidewall of the air treatment chamber  210 . Such as the chamber sidewall  220  or the inlet sidewall  260 , and the closure member  310  merges with axially extending sidewall. 
     The closure member  310  may be moveable between the open member position and the closed member position by rotating about the closure axis of rotation  540 , the closure axis of rotation is exterior to the assembly free volume  570 . Optionally, the closure axis of rotation is exterior to the air treatment chamber  210 . The closure axis of rotation  540  may extend through the closure member pocket  580 . The closure axis of rotation  540  may be parallel to the air treatment longitudinal axis  218  and/or the flow direction  550 . The closure axis of rotation  540  may be perpendicular to the air treatment longitudinal axis  218  and/or the flow direction  550 . 
     As exemplified in  FIGS.  44  and  45   , the closure member  310  may have a first end  610  comprising a rotational mount  612  and a second opposed end  614 . The closure axis or rotation may be an axis of rotation of the rotational mount  612 . The closure member  310  may extend generally perpendicular to the air treatment longitudinal axis  218  and/or the apparatus longitudinal axis  110  when in the closed position. The second opposed end  614  of the closure member  310  may rotate towards the second end  216  of the air treatment chamber  210  as the closure member moves to the open position. 
     The Closure Member is Moved by a Driving Member 
     The following is a description of a driving member  630  that is operable to move the closure member  310 , which may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the variable area inlet downstream opening, the curved closure member, the axially moving closure member, the withdrawable closure member, the openable chamber first end, the axially moveable chamber end, moving using fluid pressure, positioning of the user interface, the filter removeable past the user interface, the radially-removeable post-motor filter, the nested filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     In accordance with this aspect, as exemplified in  FIGS.  34  to  39   , the surface cleaning apparatus  100  includes a driving member  630  drivingly connected to the closure member  310 . The closure member  310  may move in a first direction  632  from the open position to the closed position. The closure member  310  may move in a second direction  634  from the closed position to the open position. The driving member  630  may be operable to move the closure member  310  in at least one of the first and second directions. Optionally, the driving member  630  is operable to move the closure member  310  in both the first direction  632  and the second direction  634 . 
     Optionally, the driving member is operable to move the closure member from the open member position to the closed member position, and the closure member is biased to the open member position by a biasing member. The driving member  630  may move the closure member to the open member position when activated, and the biasing member may move the closure member form the open member position to the closed member position when the driving member is not activated. Optionally, the driving member is operable to move the closure member from the closed member position to the open member position, and the closure member is biased to the closed member position by a biasing member. The driving member  630  may move the closure member to the closed member position when activated, and the biasing member may move the closure member form the closed member position to the open member position when the driving member is not activated. 
     It will be appreciated that the driving member  630  may be any suitable driving member, including any of the driving members described herein. 
     The driving member  630  may be any actuator that is operatively connected to (e.g., drivingly connected to) the closure member  310  to move the closure member  310  in at least one direction in response to an event, such as one or more of the suction motor being actuated or deenergized, the surface cleaning apparatus being connected to or removed from a floor cleaning unit and the air treatment assembly or a subcomponent thereof being removed or reinstalled in the surface cleaning apparatus. It will be appreciated that the closure member  310  may be automatically moved upon the occurrence of an event. The actuation of the movement of the closure member may be controlled automatically by signals generated by the control system  370  of the surface cleaning apparatus  100  (e.g., in response to changes in pressure, changes in sensor values, or changes in operational modes). 
     Accordingly, the driving member may be mechanically or electromechanically or fluidically connected to the closure member  310  to move the closure member upon the occurrence of the event. 
     The driving member  630  may comprise a closure member actuator  640 , as exemplified in  FIGS.  34  and  35   . The closure member actuator  640  may be any suitable actuator. The closure member actuator  640  may act only on the closure member  310 , e.g., it may be a separate actuator from the actuator for the suction motor  322 , may therefore be a dedicated actuator for controlling only the closure member  310 . 
     The closure member actuator  640  may be a powered actuator. A powered actuator may be an electromechanical actuator, such as a motor or solenoid. A powered actuator may be coupled to a power supply of the surface cleaning apparatus (e.g., a battery). A powered actuator may be a linear actuator. A powered actuator may be communicatively coupled to the control system to be directed thereby. Accordingly, upon actuation (e.g., a button being pushed, a soft control on a touch screen being touched or an event occurring, a signal may be sent to the closure member actuator  640  whereupon the closure member  310  is moved. 
     Alternately, an unpowered actuator may be used. The unpowered actuator may be any such actuator discussed herein such as an aneroid capsule responsive to pressure changes or a closure mechanical coupling (a mechanical linkage)  646  drivingly coupled to the manually moveable toggle  642 . The closure mechanical coupling  646  mechanically drivingly couples an upline apparatus  648  (e.g., any actuator disclosed herein) to the closure member  310 . The upline apparatus  648  may be any actuator discussed elsewhere herein, and may be manually actuated by a user or may be actuated automatically upon the occurrence of an event. 
     The closure member actuator  640  may itself comprise an on/off actuator  650  (see for example  FIGS.  34  and  35   ). Optionally, the on/off actuator  650  may be a toggle such as a button, pivoting switch or slider. The toggle may be manually moveable (e.g., a depressible button, pivoting switch or slider), or electronically activated (e.g., a soft button, such as presented on a touchscreen). The on/off actuator  650  may be the manually moveable toggle  642 . In some embodiments, the on/off actuator  650  is operable to actuate the suction motor  322  when the on/off actuator  650  is set to on and which is operable to deenergize the suction motor  322  when the on/off actuator  650  is set to off. The closure member  310  may move from the open position to the closed position in response to the on/off actuator  650  being set to off. The closure member  310  may move from the closed position to the open position in response to the on/off actuator being set to on. 
     As discussed with respect to actuator  502 , the on/off actuator  650  may be mechanically drivingly connected to the closure member  310 . In some embodiments, an on/off actuator  650  that is mechanically drivingly connected to the closure member  310  is a manually moveable slider. In embodiments in which the on/off actuator  650  is mechanically drivingly connected to the closure member  310 , the driving member  630  may include the on/off actuator  650  and the mechanical linkage  646 . 
     Alternatively, or additionally, when the on/off actuator  650  is transitioned to on or to off, a signal may be issued which causes an electromechanical member  640  (e.g., the moveable member actuator  502 ) to drive the closure member  310  to the open position or the closed position, respectively. 
     Optionally, the closure member  310  may move in response to the on/off actuator  650  after a predetermined time delay. For example, the closure member  310  may be moved to the closed position after a closing time delay of between 0.1 seconds and 10 seconds, 1 seconds and 5 seconds, or 2 seconds and 4 seconds following the transition of the on/off actuator to off. Accordingly, the air flow produced by the suction motor may terminate or substantially terminate prior to the closure member moving to the closed position. Alternately or in addition, the closure member  310  may move to the open position after the on/off actuator  650  is moved to on with a lesser opening time delay than the opening time delay. 
     Suction produced by the suction motor  322  may moves the driving member  630  which moves the closure member  310  from the closed position to the open position. Accordingly, the main on/off switch of the surface cleaning apparatus may be the on/off actuator  650 . As exemplified in  FIGS.  38  and  39   . the driving member  630  may include a piston  660  that is moveable between an open piston position and a closed piston position. The piston may be drivingly connected to (e.g., mechanically or fluidically connected to) the closure member such that the closure member is moved to the closed member position when the piston is in the closed piston position and is moved to the open member position when the piston is moved to the open piston position. The piston  660  may be moveable within a cylinder  662 . When the suction motor  322  is on, the suction generated by the suction motor  322  may drive the piston  660  to move, e.g., within the cylinder  662 . The piston  660  may be mechanically coupled to the closure member  310  to move the closure member as the piston moves. The driving member  630  may include the piston  660  and the closure mechanical linkage  646  between the piston and the closure member  310 . The piston may be biased (e.g., by biasing member  664 ) to return to the closed position. 
     Alternately or in addition, the driving member  630  may include the external conduit  140 . If an external conduit is removably insertable, then insertion of the external conduit  140  into the nozzle  180  may move the closure member  310 . The upstream end of the external conduit  140  may bear against the closure member  310  as the external conduit  140  is inserted into the nozzle, pushing the closure member  310  before it. For example, the closure member  310  may move axially to close the air treatment chamber  210  automatically when the external conduit  140  is removed. The air treatment inlet  230  may include an axially moving closure member  310  which slides closed when the external conduit  140  is removed and slides axially inwardly due to engagement between the upstream end of the external conduit  140  and the closure member  310  when the external conduit  140  is inserted. 
     As exemplified by  FIGS.  36  and  37   , the driving member  630  may comprise an engagement member  680  provided on the external conduit  140  (e.g., the end wall) and a driving actuator  682  that is operatively connected to the closure member  310  whereby upon insertion of the external conduit  140  into the dirty air inlet, the engagement member contacts the driving actuator  682  which moves the closure member from the closed position to the open position. The engagement member  680  maybe, e.g., the end cap of the external conduit  140  or a downstream end of the sidewall of the external conduit  140 . The driving actuator  682  may include, e.g., a mating engagement member that is drivingly connected to the closure member (e.g., a physical body projecting from the closure member) to be impacted by the engagement member. The driving actuator  682  may include, e.g., a toggle communicatively coupled to the closure member actuator  640 , whereby the toggle is triggered by the engagement member to actuate the closure member actuator  640 . 
     Optionally, the external conduit  140  includes a catch to engage the closure member  310  to draw the closure member  310  to the closed member position when the external conduit  140  is withdrawn. 
     Optionally, mounting the surface cleaning apparatus  100  to the floor cleaning unit  154  moves the closure member  310  from the closed position to the open position, such as by the external conduit  140  being inserted into the dirty air inlet when the surface cleaning apparatus is mounted to the floor cleaning unit, or an electromechanical member being actuated upon the surface cleaning apparatus being mounted to the floor cleaning unit. 
     Optionally, the closure member  310  may move to the open member position when the air treatment assembly  200  is coupled to the main body  120 , and moves to the closed member position when the air treatment assembly  200  is removed. A mechanical or electromechanical member may move the closure member  310  when the main body  120  and the air treatment assembly  200  are separated. The mechanical member may be, e.g., a physical catch or magnet on the main body  120  that engages the closure member  310  (e.g., a corresponding catch or magnet of the closure member) to drive the closure member to the open or closed position as the air treatment assembly  200  is joined to or removed from the main body  120 . The electromechanical member may be, e.g., the closure member actuator  640  which receives a signal to move the closure member  310  in response to detection that the air treatment assembly  200  is being removed from or coupled to the main body  120 . Optionally, the closure member  310  is biased to the open member positions by a biasing member. Optionally, removing the air treatment assembly  200  from the main body  120  overcomes the force of the biasing member to move the closure member  310  to the closed position. Optionally, the closure member  310  is biased to the closed member positions by a biasing member. Optionally, coupling the air treatment assembly  200  to the main body  120  overcomes the force of the biasing member to move the closure member  310  to the closed position. 
     Axially Moveable Chamber End 
     The following is a description of an air treatment chamber  210  wherein the chamber first end  214  is openable and a portion of the opposed end  216  is moveable (e.g., concurrently or subsequently). This aspect may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the variable area inlet downstream opening, the curved closure member, the axially moving closure member, the withdrawable closure member, the closure member moved by a driving member, the axially moveable chamber end, moving using fluid pressure, positioning of the user interface, the filter removeable past the user interface, the radially-removeable post-motor filter, the nested filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     In accordance with this aspect, the openable chamber first end  214 , which may be the forward end of the air treatment chamber or assembly, may be opened to enable the porous outlet member of the chamber (e.g., a vortex finder) to advance to a position wherein the porous member may be cleaned (e.g., to remove hair wrapped therearound) or removed for cleaning. The porous member may advance by itself or with other portions of the assembly, e.g., the rear (outlet) end of the assembly or chamber. The porous member may advance to a position proximate the open first end (the evacuation opening  410 ) or outwardly of the open first end, i.e., part or all of the porous member may advance to a position outwardly of the open first end. 
     As exemplified in  FIGS.  59  to  61   , at least a portion of an end of the air treatment chamber  210  is translatable generally parallel to the chamber longitudinal axis  218 , and will be referred to as an axially moveable end portion  680 . The axially moveable end portion is moveable between a first position ( FIG.  59   ) and a second position ( FIG.  61   ) that is axially spaced from the first position. Optionally, the second position is forward of the first position. The axially moveable end portion  680  may act as a plunger, e.g., to move debris through the chamber. 
     Accordingly, at least a portion of the chamber first end  214  may be moveable between a closed operating position ( FIG.  55   ) in which the evacuation opening  410  is closed and an open position ( FIG.  56   ) in which the evacuation opening  410  is opened. In the open position, the moveable portion of the chamber first end  214  may be open such that dirt may move out of the dirt collection region  300  through the evacuation opening  410 . In the closed position, the moveable portion of the chamber first end  214  is closed to inhibit movement of dirt out of the dirt collection region  300  through the evacuation opening  410 . Accordingly, the open position of the moveable portion of the chamber first end  214  may be referred to as an open evacuation position. 
     The moveable portion of the chamber first end  214  may comprise or consist of the front wall of the air treatment assembly (e.g., the chamber first end wall  222 ), a portion of the front wall of the air treatment assembly (e.g., movable first end portion  388 , which may be a flap, see  FIG.  50   ) or part or all of the front wall of the air treatment assembly and part of the sidewall thereof. Part or all of the inlet conduit  170  may be part of the moveable portion of the chamber first end  214  (see for example  FIG.  56   ). The moveable portion of the chamber first end  214  may include the dirty air inlet  162 , the inlet conduit  170  or a portion thereof, and/or the air treatment inlet  230  or a portion thereof. 
     Optionally, the moveable portion of the chamber first end  214  is rotatably moveable. The moveable portion of the chamber first end  214  may rotate forwardly (see for example  FIG.  56   ). Accordingly, the moveable portion of the chamber first end  214  may be rotationally mounted at a first end  700  thereof, and a second end  702  thereof opposite to the first end  700  may rotate forwardly as the chamber first end wall  222  or the portion thereof is opened. The moveable portion of the chamber first end  214  may be secured at a rotational mount  704  to a fixed wall of the air treatment assembly, such as the chamber sidewall  220  or a further portion of the chamber first end wall  222 . Accordingly, the moveable portion of the chamber first end  214  may pivot about an axis of the rotational mount  704  between the open position and the closed position. 
     Alternately, or in addition, the moveable portion of the chamber first end  214  may be translationally moveable (see for example  FIG.  60   ). The moveable portion of the chamber first end  214  may be mounted to a fixed wall of the air treatment assembly and/or the main body via a track, and may move along the track between the open and closed positions. The moveable portion of the chamber first end  214  may move linearly between the open and closed positions. The moveable portion of the chamber first end  214  may translate forwardly, as exemplified in  FIGS.  59  to  61   . Translational movement is described further elsewhere herein. 
     Alternately, or in addition, the moveable portion of the chamber first end  214  may be inflatable and deflatable. Moving between the open and closed positions may include, or consist of, inflating or deflating a member that is drivingly connected to the moveable portion of the chamber first end  214 . When an inflatable member is inflated, the moveable portion of the chamber first end  214  may be closed, and when the inflatable member is deflated the moveable portion of the chamber first end  214  may be opened. 
     It will be appreciated that the moveable portion of the chamber first end  214  may be moved by any suitable actuator and any actuator discussed herein may be sued. Accordingly, the surface cleaning apparatus may include a first end actuator to move the chamber first end  214 , which may any of the actuators described herein or a dedicated actuator. For example, the moveable portion of the chamber first end  214  is manually moveable, such as by a first end manually moveable member  670 . This manually moveable member may extend to an exterior of the surface cleaning apparatus  100 , and may be a slider or depressible button or pivotal switch. The first end manually movable member  670  may be drivingly coupled to the moveable portion of the chamber first end  214  to move the moveable portion of the chamber first end  214 . The manually moveable member may be moved by a user or moved by the docking station when the surface cleaning apparatus is docked. It will be appreciated that the first end manually moveable member  670  may be any of the manually moveable members described herein (e.g., the manually movable toggle  500 ) or a dedicated member the movement of which only affects movement of the moveable portion of the chamber first end  214 . 
     It will be appreciated that the moveable portion of the chamber first end  214  may be moved directly by a user. For example, a user may grasp the moveable portion of the chamber first end  214  and pull or push it. In such embodiments, the moveable portion of the chamber first end  214  may be referred to as a manually moveable member. 
     Alternately, the moveable portion of the chamber first end  214  may be pneumatically moveable. The moveable portion of the chamber first end  214  may be arranged to be drawn between the open and closed positions by suction generated by the suction motor  322  or a suction motor of the docking station  390 . Pneumatical movement is described further elsewhere herein. 
     Optionally, the moveable portion of the chamber first end  214  may be moved upon or subsequent to the surface cleaning apparatus being docked at a docking station  390 . For example, docking the surface cleaning apparatus  100  with the docking station  390  may move the moveable portion of the chamber first end  214  from the closed operating position to the open position. Optionally, a portion of the docking station drivingly engage the surface cleaning apparatus to open the moveable portion of the chamber first end  214  when the surface cleaning apparatus  100  is being docked. A mechanical linkage may be provided whereupon the docking station may push or pull the moveable portion of the chamber first end  214  open. The moveable portion of the chamber first end  214  maybe biased to the closed operating position. Undocking the surface cleaning apparatus  100  from the docking station  390  may move the moveable portion of the chamber first end  214  from the open position to the closed operating position. Alternately or in addition, a portion of the docking station  390  may be coupled to the moveable portion of the chamber first end  214  to close the chamber first end  214  when the surface cleaning apparatus  100  is being undocked. For example, a catch on the docking station  390  may pull a door shut or pull a component to a closed position as the surface cleaning apparatus  100  is pulled away from the docking station. 
     The axially moveable end portion  680  may be at least a portion of the chamber second end  216  and may also include at least a portion of the chamber first end  214 . The chamber second end  216  may be moveable after or with the opening of the chamber first end  214 . Optionally, the chamber second end  216  may not be moveable while the chamber first end  214  remains closed. 
     It will be appreciated that the surface cleaning apparatus  100  may include two axially moveable end portions  680 , i.e., at least a portion of the chamber first end  214  and at least a portion of the chamber second end  216 . For example, as exemplified in  FIGS.  59 - 61   , the first and second ends  214 ,  216  may each translate forward. In embodiments in which the apparatus includes two axially moveable end portions  680 , the portions may be secured together such that one can be moved by moving another. One of the portions may be drivingly connected to the other portion. The portions may be connected by a linking member  734 . The linking member  734  may be a mechanical linkage. For example, the linking member  734  may include an arm, such as an arm of fixed length or a telescoping arm. The linking member  734  may include an electromechanical member. The electromechanical member of the linking member  734  may be responsive to movement of one position, and respond by moving the other simultaneously or sequentially (e.g., after a predetermined time delay or change in the separation distance  684 ). 
     Portions secured together may be fixed together with a constant separation distance  684  between them (e.g., translate together as one body), or may be separated by a variable separation distance  684 . For example, portions may be joined by a telescoping arm such that a range of separation distances are possible. 
     The axially moveable end portion  680  may include the chamber second end wall  224  or a portion thereof and/or the air treatment outlet  232  or a portion thereof. The air treatment outlet  232  may include a porous member  422  (e.g., a screen or a pre-motor filter received in the air treatment outlet  232 ) and the axially moveable end portion  680  may include at least a portion of the porous member  422 , and optionally the entire porous member. 
     If a pre-motor filter is provided, then the axially moveable end portion  680  may include at least a portion of the pre-motor filter housing  334 , e.g., a forward portion  686  of the pre-motor filter housing and a laterally encircling wall  688 . Optionally, the axially moveable end portion  680  may not include an end wall  690  of the pre-motor filter housing  334  that is at an end of the pre-motor filter housing which is farthest from the chamber first end  214  (e.g., a rearward end of the pre-motor filter housing  334 , as exemplified). 
     Alternately, or in addition, the axially moveable end portion  680  may include at least a portion of or the entirety of the suction motor housing  324  and accordingly the suction motor  322  may be moveable with the axially moveable end portion  680 . 
     The axially moveable end portion  680  may be moveably secured to a supporting sidewall  692  of the air treatment assembly  200  and/or the main body  120 . As exemplified, the supporting sidewall  692  may include the chamber sidewall  220  and/or the main body sidewall  192 . 
     The surface cleaning apparatus  100  may include, as exemplified, a track  730  along which the axially moveable end portion  680  moves. The axially moveable end portion  680  may slide along the track  730 . The track  730  may be a linear track  730 . The track  730  may be parallel to the supporting sidewall  692  of the surface cleaning apparatus  100 . The track  730  may be provided in the supporting sidewall  692 . For example, the track  730  may include a member embedded in the supporting sidewall  692 , or may include a channel formed in the supporting sidewall  692 . Optionally, the supporting sidewall  692  and the track  730  are each axially extending. 
     The track  730  may include a sealing member  732  received between the axially moveable end portion  680  and a wall along which the axially moveable end portion  680  moves. The sealing member  732  may be, e.g., a felt sealing member. The sealing member  732  may separate the axially moveable end portion  680  from a wall (e.g., the chamber sidewall  220 ) along which the axially moveable end portion slides. The sealing member  732  may be sandwiched between the axially moveable end portion  680  and the chamber sidewall  220  throughout the movement between the closed position and the open position. 
     It will be appreciated that the track  730  may be a dedicated track along which an axially moveable end portion  680  moves, with a separate track provided for each axially moveable end portion. However, as exemplified, in some embodiments more than one axially moveable end portion is carried by a common track  730 . As exemplified, an axially moveable second end portion  680   b  is coupled to the track directly while an axially moveable first end portion  680   a  is coupled to the track indirectly (e.g., via the axially moveable first end portion  680   a ). The axially moveable first end portion  680   a  is an axially moveable end portion  680  that includes at least a portion of the chamber first end  214 . The axially moveable second end portion  680   b  is an axially moveable end portion  680  that includes at least a portion of the chamber second end  216 . 
     The track may include a rail  710  between the axially moveable end portion  680  and the supporting sidewall  692 . The axially moveable end portion  680  may ride along the rail  710  as the axially moveable end portion  680  moves between the first and second positions. 
     In some embodiments, the rail  710  is a telescoping rail, as exemplified. The telescoping rail may include at least a first rail body  712  and a second rail body  714 . The second rail body may be moveably secured to the first rail body  712  and moveable between a retracted position generally coextensive with the first rail body  712  and an extended position extending past an end of the first rail body  712 . The first rail body  712  may be secured to one of the axially moveable end portion  680  and the supporting sidewall  692 , while the second rail body  714  may be secured to the other of the axially moveable end portion  680  and the supporting sidewall  692 . 
     Accordingly, it will be appreciated that the at least a portion of the second end portion  680   b  may move concurrently or sequentially (e.g., subsequent to) with the at least a portion of the first end portion  680 a. The subsequent movement may be delayed by a predetermined time period. The predetermined time period may be, e.g., between 0.1 seconds and 10 seconds, between 0.1 seconds and 5 seconds, or between 0.1 seconds and 2 seconds. Additionally, or alternatively, the subsequent movement may be delayed by a predetermined change in the separation distance  684 . The predetermined change may be, e.g., between 0.1 times and 2 times the original separation distance, between 0.2 times and 1 time the original separation distance, or between 0.2 times and 0.5 times the original separation distance. A delay allows dirt in the air treatment chamber to decompress, and may loosen the dirt. For example, elongated dirt, such as hair. may decompress. 
     Optionally, the at least a portion of the second end portion  680   b  is moved by opening the at least a portion of the first end portion  680 a, but the separation distance  684  between the two is greater subsequent to the movement than prior to the movement. A greater separation distance provides further space for the dirt received therebetween to decompress. 
     The axially moveable end portion  680  may be moved by any suitable driving member, including any discussed with moving the chamber first end  214  to the open position. 
     The air treatment chamber  210  may be emptiable by opening the chamber first end  214  and moving at least a portion of the chamber second end  216  axially towards the chamber first end  214 . 
     Moving Using Fluid Pressure 
     The following is a description of moving a portion a fluid driven moveable member of the surface cleaning apparatus (e.g., part or all of the first end  214  and or the second opposed end  216 ) via fluid pressure, which may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the variable area inlet downstream opening, the curved closure member, the axially moving closure member, the withdrawable closure member, the closure member moved by a driving member, the operable chamber first end, the axially moveable chamber end, positioning of the user interface, the filter removeable past the user interface, the radially-removeable post-motor filter, the nested filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     In accordance with this aspect, as exemplified in  FIGS.  57  and  58   , a fluid driven moveable member  720  of the surface cleaning apparatus  100  is moveable via fluid pressure between a first position and a second position. It will be appreciated that the fluid pressure may be air pressure (i.e., suction) generated by an air moving member of the surface cleaning apparatus or a docking station or exhaust air from a suction motor. 
     If a docking station is provided, then when the apparatus is docked, the fluid driven moveable member  720 , which is in the first position, may be received in the evacuation air flow path such that air flow through the evacuation air flow path will act on the fluid driven moveable member  720  when the fluid driven moveable member is in the first position to move the fluid driven moveable member  720  to a second or evacuation position. In other words, air flow through the evacuation air flow path may move the fluid driven member from the first position (i.e., towards the second position). Accordingly, the first position may be referred to as the operational, cleaning or use position. Such air flow may be produced by a suction motor in the surface cleaning apparatus, the docking station or both. 
     Alternately or in addition, air flow through the apparatus air flow path when the surface cleaning apparatus is not docked may act on the fluid driven moveable member  720  to move the fluid driven member from the first position to the second. 
     It will be appreciated that the fluid driven moveable member  720  may move (push or pull) part or all of the first end  214  and or the second opposed end  216  axially, such as along a rail  710  as discussed previously. 
     An air impermeable member may be moved to enable air flow to move the fluid driven moveable member  720 . For example, a valve or other closure member may be provided to close part of the air flow path  160  such that air flow may move the fluid driven moveable member  720 . When it is desired to empty the dirt collection region  300 , the air impermeable member may be moved to an evacuation position. In which air flow may act on the fluid driven moveable member  720  to move the fluid driven moveable member  720  and therefore part or all of the first end  214  and or the second opposed end  216  may be moved. For example, the valve may be moved to close the vortex finder (e.g., it may be moved to close the outlet port at the downstream end of the vortex finder), e.g., by an actuator as discussed elsewhere herein or by air flow from the suction motor of the surface cleaning apparatus and/or the docking station drawing air in a reverse flow direction through the air treatment assembly thereby pushing or drawing the valve to close the port. When this occurs, the air flow path between the suction motor and the vortex finder may become sealed and form an evacuation air flow path and air flow may push the second opposed end  216 , and the first end  214  if linked thereto) axially forwardly to open the dirt collection region. 
     To enable the apparatus air flow path to be active (i.e., the surface cleaning apparatus is to be used to clean a surface), the air impermeable member (e.g., valve) is moved, (e.g., by air flow or a biasing member or an electromechanical member or the like) to an operational position (e.g., the valve does not close the outlet port of the vortex finder). It will be appreciated that the valve may be moveable axially. 
     It will be appreciated that the fluid driven moveable member  720  may include or consist of the chamber first end  214  and/or a moveable portion thereof and/or the chamber second end  216  or a moveable portion thereof and the ends may be linked for movement as discussed previously. 
     Accordingly, the moveable portion of the chamber second end may move forwardly as dirt is sucked out of dirt collection region  300  when the surface cleaning apparatus  100  is docked with the docking station  390 . 
     Optionally, the fluid driven moveable member  720  is biased to the evacuation (dirt emptying) position. Air pressure may move the fluid driven moveable member  720  to the operating (surface cleaning) position. When suction is terminated, then the fluid driven moveable member  720  moves to the evacuation position. Alternately, the fluid driven moveable member  720  may be biased to the operating position. Suction may move the fluid driven moveable member  720  to the evacuation position. When suction is terminated, then the fluid driven moveable member  720  moves to the operating position. Alternately, the fluid driven moveable member  720  is not biased to either position. Suction from the air moving member of the evacuation air flow path  392 , through the evacuation air flow path  392 , may move the fluid driven moveable member  720  to the evacuation position. Suction from the suction motor  322 , through the apparatus air flow path  160 , may move the fluid driven moveable member  720  to the operating position. 
     Positioning of the User Interface 
     The following is a description of the positioning and mounting of the user interface  360  on the handle, which may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the variable area inlet downstream opening, the curved closure member, the axially moving closure member, the withdrawable closure member, the closure member moved by a driving member, the operable chamber first end, the axially moveable chamber end, moving using fluid pressure, the filter removeable past the user interface, the radially-removeable post-motor filter, the nested filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     The user interface may be provided on the handle, e.g., an upper end of the handle or a lower end of the handle  124 , an energy storage member  350 , an energy storage member housing  381  ( FIG.  5   ) configured to receive the energy storage member  350 , or a supporting body that overlies a portion of the main body  120  such as a rearwardly or upwardly facing portion of a body 
     in accordance with this aspect, as exemplified in  FIGS.  62  to  68    the user interface  360  may be provided at an upper end of the pistol grip handle  124 . This location provides the user interface at a convenient location for a user of the interface. 
     The user interface  360  may be located within an upper half, upper third, or upper quarter of a length of the handle  124  along the handle longitudinal axis  128  when the apparatus upper end  106  is above the apparatus lower end  108 . 
     Alternately, the user interface  360  may be located within a lower half, lower third, or lower quarter of a length of the handle  124  along the handle longitudinal axis  128  when the apparatus upper end  106  is above the apparatus lower end  108 . 
     Optionally, the user interface  360  is on a rear portion of the upper end of the pistol grip handle  124  when the apparatus rear end  104  is rearward of the apparatus front end  102 . 
     Optionally, the user interface  360  may be above the hand grip portion  126  of the handle  124 . 
     Alternately, as exemplified in  FIGS.  69  and  70    the user interface  360  may overly the main body housing  122 , such as the portion of the main body housing  122  that houses the suction motor  322 . Accordingly, the user interface  360  may overly or be rearward of the suction motor housing  324 , at a rear end of the main body. As exemplified, the main body housing  122  has a rear end  756 , and the user interface  360  may overly the rear end  756 . The rear end  756  may be a rear end of the suction motor housing  324 . Accordingly, the user interface may be a separate member such that the user interface is not attached to the suction motor housing or the main body and may be attached to the handle but positioned overlying the motor housing, e.g., a rear end of the main body. 
     As exemplified in  FIGS.  69  and  70   , the user interface  360  is at a rear end of the main body housing  122  and overlies a rear end of the suction motor housing  324 . The user interface  360  may be spaced from the suction motor housing  324  by a separation air gap  742 . However, it will be appreciated that the user interface  360  may alternatively, or additionally, be separated from the main body housing  122  by one or more other bodies, such as a post-motor filter  332  or post-motor filter housing  340 . 
     The user interface  360  may include or be provided on a supporting body  740 . The supporting body  740  is configured as a mount to receive the user interface  360  at a desired location, e.g., overlying the main body housing  122  (e.g., overlying or rearward of the suction motor housing  324 , at a rear end of the main body). Accordingly, the supporting body  740  may extend over (e.g., spaced from and facing, or facing and optionally abutting) the main body housing  122 . As exemplified in  FIGS.  69  and  70   , the supporting body  740  is part of the rear end of the hand vacuum cleaner and is mounted rearward of the suction motor housing  324 . 
     In this example, the user interface  360  may include a facing surface  744  facing or directly facing a housing facing surface  746  across the gap  742 . Optionally, the facing surface  744  and the housing facing surface  746  are separated by a generally constant distance across the faces. 
     By using a supporting body  740 , the user interface  360  may be rearward of the main body housing. The user interface  360  may overly the main body rear face  194  of the main body housing  122 . The main body rear face  194  may form the housing facing surface. 
     Accordingly, as exemplified, the user interface  360  faces rearwardly. In other words, the user interface includes a surface visible from rearward of the surface cleaning apparatus along the apparatus longitudinal axis. 
     Optionally, the user interface  360  may form a rear face of the surface cleaning apparatus  100  as a whole. In other words, the surface cleaning apparatus may not include any further body rearwardly overlying a rear face of the user interface  360 . Optionally, the user interface  360  forms a rearmost portion of the apparatus upper end  106 . 
     As exemplified in  FIGS.  69  and  70   , the surface cleaning apparatus  100  includes a support arm  750  that retains the supporting body  740  at the desired location. The support arm  750  extends between a first arm end  752  and a second arm end  754 . The first arm end  752  may be secured or directly secured to the main body  120  (e.g., the main body housing  122 ), the suction motor housing and/or the handle. For example, the support arm may be a separate part that is secured (e.g., mounted to) the main body  120 . Alternately or in addition, the support arm  750  (e.g., first arm end  752 ) may be secured to the handle, e.g., an upper end fop the handle. 
     The second arm end  754  provides support for the user interface  360  and may be secured or directly secured to the user interface  360  and/or secured or directly secured to the supporting body  740 . Optionally, as exemplified, the support arm  750  may join lower ends of the supporting body  740  and the main body housing  122 . Accordingly, the support arm  750  enables the support body  740  to be mounted at an alternate location, such as a rear end of the main body. 
     As exemplified, the support arm may extend rearwardly from the main body  120 . The support arm  750  may extend from the main body rear face  194 , and may extend to the supporting body  740 . 
     Alternately or in addition, the support arm  750  may extend from the pistol grip handle  124 , such as the upper end  130  of the pistol grip handle  124  (i.e., above the hand grip portion). The support arm  750  may extend rearwardly from the upper end  130  of the pistol grip handle  124 . Accordingly, the support arm may be or may extend to a position that is rearward of the suction motor. 
     It will be appreciated that in some embodiments the gap  742  may be contained within and/or exterior to cladding  758 , which bridges the lateral edges  760  of the gap (Le., radially outward edges with respect to the apparatus longitudinal axis  110 ). Accordingly, the gap  742  may not be visible from an exterior of the surface cleaning apparatus  100 . Optionally, the cladding  758  holds the supporting member  740  in position, e.g., it may be secured to the rear end of the main body (e.g., the motor housing) and/or upper end  130  of the handle, and the support arm  750  may not be included. 
     Optionally, the user interface  360  overlying the main body housing does not include any interface toggles or controls  362 . The user interface  360  overlying the main body housing  122  may include one or more information displays  364 , without including interface toggles  362 , such as to avoid running wires from that interface back through the motor housing. If controls are provided or a readout from sensors is required, then wires may extend along of through the support arm  750 . 
     In some embodiments, as exemplified in  FIGS.  59  to  61    the main body  120  has a cavity  770  provided at the apparatus rear end  104 , and the suction motor  322  is positioned in the cavity  770  and a user interface  360  is provided on or at the apparatus rear end  104 . The suction motor housing  324  may also be in the cavity  770 . The user interface  360  may accordingly overly the suction motor  322  and/or suction motor housing  324  in the cavity  770 . 
     The user interface  360  may be separated from the suction motor  322  and/or suction motor housing  324  by a portion of the cavity  770  (i.e., an air gap). The apparatus rear end  104  includes an apparatus rear wall  772 , which may be a rear wall of the cavity  770 . The user interface  360  may be provided on the apparatus rear wall  772 . 
     Alternately, or in addition, as exemplified in  FIGS.  69  and  70   , the surface cleaning apparatus  100  may include an annular portion  780 . The annular portion  780  may be a ring-shaped body or a portion of an annular body (e.g., an annulus sector) that has a radial or generally radial outwardly facing surface. The annular portion  780  may be integrally formed with the main body  120 , or, as exemplified, an independently formed body directly or indirectly secured to the main body  120 , e.g., by a support arm  740  and or a supporting body  740 . 
     Optionally, the annular portion is part of the apparatus rear end  104 . 
     The user interface  360  may be provided on the annular portion  780  (e.g., on the radial or generally radial outwardly facing surface). The user interface  360  may be secured to the annular portion or be part of the annular portion. 
     As exemplified in  FIG.  70   , the user interface  360  may be curved to follow an annular surface of the annular portion  780 . The user interface  360  may include a substrate  782 , such as a flexible panel. The substrate  782  may be curved when mounted to the annular portion  780 . 
     It will be appreciated that, in such an embodiment, the user interface  360  may include one or more interface toggles  362  or controls and/or information displays  364  on the substrate  782 . 
     As exemplified, the user interface  360  may include an information display  364  having a display surface that faces radially outward. For example, the information display  364  may be a screen having a display surface facing radially outward (i.e., generally perpendicular to an annular longitudinal axis  784  of the annular portion  780 ) and optionally upwardly. The information display  364  may be, e.g., an illuminated icon with an illuminated surface facing radially outward. 
     Optionally, the substrate  782  has a radially outward-facing surface on which the information display is provided. 
     The user interface  360  may include a plurality of information displays facing radially outward. 
     Optionally, a protective cover  786  overlies the information display  364 . It will be appreciated that the user interface  360  may also, or alternatively, include an information display  364  having a display surface that faces rearwardly. 
     Filter Removeable Past the User Interface 
     The following is a description of a filter that is visible through and/or removeable through the user interface  360 , which may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the variable area inlet downstream opening, the curved closure member, the axially moving closure member, the withdrawable closure member, the closure member moved by a driving member, the openable chamber first end, the axially moveable chamber end, moving using fluid pressure, positioning of the user interface, the radially-removeable post-motor filter, the nested filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     In accordance with this aspect, as exemplified in  FIGS.  71  and  72   , the surface cleaning apparatus  100  includes a filter  790  that is removeable from an installed position ( FIG.  71   ) to a removed position ( FIG.  72   ) outside the main body housing  122 . The filter  790  is moveable between the installed and removed positions along a removal path  792 . As exemplified, the removal path  792  may extend through the user interface  360  between the installed position and the removed position. Accordingly, a rearwardly removable filter may be removable while the user interface  360  remains in position as the filter is removed. The filter  790  may be, e.g., the post-motor filter  332 . 
     As exemplified, the filter  790  may be a rearwardly removeable filter and the removal path  792  may extend generally parallel to the apparatus longitudinal axis  110 , or may include at least a rearward component to a motion vector at each point along the removal path  792 . 
     When installed, the filter  790  may be at the apparatus rear end  104 . The filter  790  may be part of the apparatus rear end  104 . In some embodiments, the apparatus rear end  104  includes a rear wall  772  (e.g., the main body rear wall  196 ), and the rear wall  772  may be part of a filter housing  796  for the filter  790  (e.g., the post-motor filter housing  340 ), and may optionally remove with the filter  790 . 
     As exemplified, the user interface  360  is provided at the apparatus rear end  104  and may be part of the apparatus rear end  104 . 
     As discussed previously, the user interface may be on an annular member or an annulus sector or it may be part of an annular member or an annulus sector. As such, the user interface  360  may be provided radially outward of the filter  790  and/or the filter housing  796  in the installed position, radially outward of the filter in a partially removed position, and/or radially outward of the removal path  792 . If the user interlace  360  is has a central hollow portion (e.g., it may be annular), then the user interface  360  may surround the filter  790  and/or the filter housing  796  in the installed position, radially outward of the filter in a partially removed position, and/or radially outward of the removal path  792 . 
     Optionally, the user interface  360  is part of the filter housing  796 . 
     Radially-Removeable Post-Motor Filter 
     The following is a description of a radially-removable post-motor filter  332 , which may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the variable area inlet downstream opening, the curved closure member, the axially moving closure member, the withdrawable closure member, the closure member moved by a driving member, the openable chamber first end, the axially moveable chamber end, moving using fluid pressure, positioning of the user interface, the filter removeable past the user interface, the nested filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     In accordance with this aspect, as exemplified in  FIGS.  73  and  74   , a filter  800  is removable radially outwardly with respect to the apparatus longitudinal axis  110 . The filter  800  (e.g., which may be the post-motor filter  332 ) may be removeable in a direction that is generally perpendicular to the apparatus longitudinal axis  110 . As exemplified, the filter  800  is removeable between an installed position ( FIG.  73   ) and a removed position ( FIG.  74   ), and is removeable along a removal path  802 . The removal path  802  may be a radially extending path, as exemplified. The removal path  802  may be a laterally extending path  802 . 
     The filter  800  may overly at least a portion of the suction motor  322  and/or the suction motor housing  324 . Optionally, the filter  800  is seated on the suction motor housing  324 . 
     The surface cleaning apparatus  100  may include a plurality of radially removeable filters  800  (e.g., two or more). The plurality of radially removeable filters  800  may each be separately removeable or concurrently removably. Each of the plurality of radially removeable filters may separately overly the at least a portion of the suction motor  322  and/or the suction motor housing  324 . Each of the plurality of radially removeable filters may separately be seated on the suction motor housing  324 . 
     One or more of the plurality of radially removeable filters  800  may remove in a different direction to one or more other filters of the plurality of filters. 
     As exemplified, two filters  800 , each of which is shaped as an annulus sector (e.g., they may be semi-circular filters  800 ), are provided. The filters  800  are removeable in opposite directions. As exemplified, the removal path of each filter is generally horizontal (lateral) when the apparatus upper end  106  is above the apparatus lower end  108 , and may be generally parallel to the apparatus transverse axis  114 . It will be appreciated that if the position of the filters is rotated 90°, then the filters may be removable radially but one would remove upwardly and one would remove downwardly. 
     Nested Filter 
     The following is a description of a filter that is at least partially nested within the air treatment outlet  232 , which may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the variable area inlet downstream opening, the curved closure member the axially moving closure member, the withdrawable closure member, the closure member moved by a driving member, the openable chamber first end, the axially moveable chamber end, moving using fluid pressure, the user interface on the handle, the user interface overlying the main body housing, the user interface on an annular portion, the filter removeable past the user interface, the radially-removeable post-motor filter, the ultraviolet disinfection, and the dirt scoop, which are set out herein. 
     In accordance with this aspect, as exemplified in  FIGS.  62  to  68   , a filter, which may be the pre-motor filter  330 , is at least partially nested within the air treatment outlet  232 . Nesting the filter may allow the surface cleaning apparatus  100  to have a shorter axial length without shortening a pre-motor filter. 
     The porous member  422  of the air treatment outlet  232  may be rigid, e.g., it may be a screen that is made of a mesh material. As exemplified, the screen may be conical or frusto-conical in shape. It will be appreciated that the air treatment outlet  232  may be any shaped which enables a filter to be at least partially nested therein. 
     The filter may itself be rigid. For example, a pre-motor filter  330  may comprise a pleated filter material  814 . The pleated filter material includes pleats  816 , and the pleats  816  may extend in a forward/rearward direction. The pleats  816  may extend generally parallel to the apparatus longitudinal axis  110 . The pre-motor filter  330  may have a hollow interior  818 . The hollow interior  818  may be downstream of the pleated filter material  814 . The hollow interior  818  may have an outlet end  820 , and a suction motor inlet end  822  of the suction motor  322  may face the outlet end  820  of the hollow interior  818  when the filter is in an operational position. It will be appre 3 ciated that any filter material f any shape may be used. 
     The filter is at least partially nested in the air treatment outlet  232 , e.g., a vortex finder. The filter may extend part way into the air treatment outlet  232  or substantially the entre way into the air treatment outlet  232 . As exemplified in  FIG.  64   , the forward end of the filter is located at a forward end of a vortex finder. 
     It will also be appreciated that part or all of the filter may be nested into the air treatment outlet  232 . As exemplified in  FIG.  64   , about half of the filter is nested in the air treatment outlet  232 . As exemplified, the filter may include an unnested (rearward) end  812  opposite the nested end  810 , wherein the unnested end being outside the air treatment chamber  210  and/or outside the air treatment outlet  232 . The unnested end  812  may have a larger diameter than would be practical within the air treatment outlet  232 . It will be appreciated that 25%, 50%, 75% or more of the filter may be nested in the air treatment outlet  232 . 
     In order to enable more of the filter to be nested in the air treatment outlet  232 , the filter may have a similar shape as the air treatment outlet  232  but with a smaller diameter. As exemplified, the filter is a rigid frusto-conical pre-motor filter. As the air treatment outlet  232  is frusto-conical, the filter may also be frusto-conical but with a diameter at a nested (forward) end  810  that is small enough to allow the air flow path to extend past the nested end  810  internal of the air treatment outlet  232 . 
     As exemplified, the air treatment outlet  232  and the nested end  810  of the filter are each axially inward of the air treatment chamber inlet opening  234 . 
     Ultraviolet Disinfection 
     The following is a description of ultraviolet disinfection, which may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the variable area inlet downstream opening, the curved closure member, the axially moving closure member, the withdrawable closure member, the closure member moved by a driving member, the openable chamber first end, the axially moveable chamber end, moving using fluid pressure, positioning of the user interface, the filter removeable past the user interface, the radially-removeable post-motor filter, the nested filter, and the dirt scoop, which are set out herein. 
     In accordance with this aspect, as exemplified in  FIGS.  75  and  76   , the surface cleaning apparatus  100  includes an ultraviolet light source  830 . The ultraviolet light source  830  is operable to generate ultraviolet light. 
     The ultraviolet light source  830  may be arranged to direct the ultraviolet light onto an interior and/or exterior surface of the surface cleaning apparatus  100  to disinfect the interior and/or exterior surface. For example, the light may be used to kill biological material on an interior surface that would cause an odour. The light may be used to kill biological material on an exterior surface that could be harmful to the user when the user uses the surface cleaning apparatus (e.g., the exterior surface may be a surface of the handle). 
     The ultraviolet light source  830  may be arranged to direct the ultraviolet light into a light carrying structure  832  (such as a light pipe) to be carried by the light carrying structure  832  to a distal location. For example, the source may be provided in the main body housing and the light carrying structure may carry the light to the handle and/or the interior of the air treatment chamber. 
     The surface cleaning apparatus  100  may include at least one member that is transparent to ultraviolet light, and the ultraviolet light may be directed through the transparent member (inwardly, e.g., into an air treatment chamber, or outwardly, through a handle). For example, the transparent member may be a wall of the handle  124 , and light may be directed to the external surface of the UV transparent wall of the handle  124  from within the handle  124  to disinfect an external surface of the handle  124 . 
     The ultraviolet light source  830  may be activated when the surface cleaning apparatus  100  is docked at a docking station or placed in a storage position wherein a user is not holding the surface cleaning apparatus. 
     Dirt Scoop 
     The following is a description of a dirt scoop, which may be used by itself or in combination with one or more of the rib arrester, the air inlet with a side opening, the variable area inlet downstream opening, the curved closure member, the axially moving closure member, the withdrawable closure member, the closure member moved by a driving member, the openable chamber first end, the axially moveable chamber end, moving using fluid pressure, positioning of the user interface, the filter removeable past the user interface, the radially-removeable post-motor filter, the nested filter, and the ultraviolet disinfection, which are set out herein. 
     In accordance with this aspect, as exemplified in  FIGS.  75  and  76    the surface cleaning apparatus  100  may include a dirt scoop  840 . The dirt scoop  840  is moveable between an operational position ( FIG.  75   ) and an evacuation position ( FIG.  76   ) wherein as the dirt scoop moves between the operational position and the evacuation position, the dirt scoop physically engages dirt in the air treatment member and moves the dirt outwardly from the air treatment member. 
     As exemplified, in the operational position, the dirt scoop  840  is located in the air treatment chamber  210 . It will be appreciated that the dirt scoop may be of any shape and may extend any amount into the air treatment member. As exemplified, the dirt scoop  840  is a linearly extending member. 
     The dirt scoop  840  may be mounted to a moveable carrying member  842 . As exemplified, the dirt scoop  840  is mounted to or provided as part of the air treatment inlet  230 . The moveable carrying member  842  may move when the evacuation opening  410  is opened. The moveable carrying member  842  may be pivotally mounted, and may move about a pivot axis when the evacuation opening  410  is opened. The dirt scoop  840  moves with the moveable carrying member  842 . 
     As the dirt scoop is moves with, e.g., the air treatment inlet  230 , it passes through part of the free volume  470  of the air treatment chamber  210  and may help to dislodge dirt within the air treatment chamber. The dirt scoop may sweep through part or all of the free volume  470  to dislodge dirt and move the dirt towards or out the evacuation opening  410 . 
     As exemplified, the dirt scoop  840  may extend between a first end  850  and an opposite second end  852 , with the first end  850  mounted to the moveable carrying member  842  and the second end  852  following an arc-shaped path  854  through the chamber. 
     As exemplified, the moveable carrying member  842  may be the air treatment inlet  230 . The dirt scoop may include a linearly extending member  846  extending into the air treatment chamber from the moveable carrying member. The dirt scoop may extend along a scoop longitudinal axis  844  between a first end and a second end opposite the first end. 
     The dirt scoop may be rigid or flexible. 
     The dirt scoop  840  may be positioned adjacent the chamber sidewall  220  in the operational position. The dirt scoop  840  may be spaced from the chamber sidewall  220  by, e.g., less than 10 mm, less than 5 mm, or less than 1 mm in the operational position. The scoop longitudinal axis  844  may be generally parallel to the chamber sidewall  220  in the operation position. As such, the dirt scoop may be positioned out of the air flow path of air in the air treatment chamber (e.g., it may be flush with or recessed into a sidewall of the air treatment chamber. 
     As used herein, the wording “and/or” is intended to represent an inclusive—or. That is, “X and/or Y” is intended to mean X or Y or both, for example. As a further example, “X, Y, and/or Z” is intended to mean X or Y or Z or any combination thereof. 
     While the above description describes features of example embodiments, it will be appreciated that some features and/or functions of the described embodiments are susceptible to modification without departing from the spirit and principles of operation of the described embodiments. For example, the various characteristics which are described by means of the represented embodiments or examples may be selectively combined with each other. Accordingly, what has been described above is intended to be illustrative of the claimed concept and non-limiting. It will be understood by persons skilled in the art that other variants and modifications may be made without departing from the scope of the invention as defined in the claims appended hereto. The scope of the claims should not be limited by the preferred embodiments and examples, but should be given the broadest interpretation consistent with the description as a whole. 
     Clause Set A 
     
         
         1. A surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment chamber provided in the air flow path, the air flow chamber having an air treatment chamber air inlet and an air treatment chamber air outlet; and,   (c) a motor and fan assembly provided in the air flow path,   wherein the air treatment chamber air inlet of the air flow chamber comprises a conduit having a sidewall that extends longitudinally in a flow direction from an inlet end to an outlet end, and the sidewall has a porous section provided therein.   
     
         2. The surface cleaning apparatus of clause 1 wherein the porous section comprises mesh material. 
         3. The surface cleaning apparatus of clause 1 wherein the outlet end comprises an end wall and the sidewall has a side wall opening that is positioned upstream of the end wall. 
         4. The surface cleaning apparatus of clause 3 wherein the porous section is provided upstream of the end wall and is opposed to the side wall opening. 
         5. The surface cleaning apparatus of clause 3 wherein the end wall is removably mountable on the outlet end. 
         6. The surface cleaning apparatus of clause 3 wherein the porous section and the side wall opening have downstream ends that are located at the end wall. 
         7. The surface cleaning apparatus of clause 1 wherein the air treatment chamber air inlet is positioned internal of the air treatment chamber. 
         8. The surface cleaning apparatus of clause 7 wherein the air treatment chamber air inlet is integrally formed with the air treatment chamber. 
         9. The surface cleaning apparatus of clause 1 wherein the conduit is removably receivable in the dirty air inlet. 
         10. The surface cleaning apparatus of clause 9 wherein the outlet end comprises an end wall and the sidewall has a side wall opening that is positioned upstream of the end wall. 
         11. The surface cleaning apparatus of clause 10 wherein the porous section is provided upstream of the end wall and is opposed to the side wall opening. 
         12. The surface cleaning apparatus of clause 9 wherein the air treatment chamber air inlet comprises a longitudinally extending inlet passage having a passage sidewall with openings wherein, when the conduit is inserted into the longitudinally extending inlet passage, the porous section and the sidewall opening align with the openings of the longitudinally extending inlet passage. 
         13. The surface cleaning apparatus of clause 1 wherein the air treatment chamber comprises a cyclone, the outlet end comprises an end wall and the sidewall has a side wall opening that is positioned upstream of the end wall and a tangential inlet extends downstream from the side wall opening. 
         14. A surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment chamber provided in the air flow path, the air flow chamber having an air treatment chamber air inlet and an air treatment chamber air outlet; and,   (c) a motor and fan assembly provided in the air flow path,   wherein the air treatment chamber air inlet of the air flow chamber comprises an axial extending conduit having a sidewall that extends longitudinally in a flow direction from an inlet end to an outlet end, and the sidewall has a sidewall opening provided therein whereupon, on exiting the sidewall opening, the air enters the air treatment chamber.   
     
         15. The surface cleaning apparatus of clause 14 wherein the outlet end comprises an end wall. 
         16. The surface cleaning apparatus of clause 15 wherein the sidewall opening is located adjacent the end wall. 
         17. The surface cleaning apparatus of clause 14 wherein the conduit has a porous section. 
         18. The surface cleaning apparatus of clause 17 wherein the porous section comprises mesh material. 
         19. The surface cleaning apparatus of clause 17 wherein the outlet end comprises an end wall, the porous section is provided upstream of the end wall and is opposed to the side wall opening. 
       
    
     Clause Set B 
     
         
         1. A surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment chamber provided in the air flow path, the air flow chamber having an air treatment chamber air inlet and an air treatment chamber air outlet; and,   (c) a motor and fan assembly provided in the air flow path,   wherein the air treatment chamber air inlet of the air flow chamber comprises an axially extending conduit having a sidewall that extends longitudinally in a flow direction from an inlet end to an outlet end, the outlet end having an outlet port provided in the sidewall, wherein a cross-sectional area of the outlet port is variable.   
     
         2. The surface cleaning apparatus of clause 1 wherein the outlet port comprises an axially extending opening in the sidewall, the axially extending opening has an axial length. 
         3. The surface cleaning apparatus of clause 2 wherein the sidewall terminates at a terminal end which is located at the outlet end and the axially extending opening extends to the terminal end of the sidewall. 
         4. The surface cleaning apparatus of clause 3 further comprising an end wall that is provided at the outlet end of the conduit, the end wall extends transverse to the flow direction. 
         5. The surface cleaning apparatus of clause 4 wherein the axially extending opening extends to the end wall. 
         6. The surface cleaning apparatus of clause 4 wherein the end wall is moveably axially whereby the axial length of the outlet port is varied. 
         7. The surface cleaning apparatus of clause 1 wherein the cross-sectional area of the outlet port is varied based upon an air flow rate of air in the air flow path. 
         8. The surface cleaning apparatus of clause 1 wherein, when the air flow rate is a first flow rate, the outlet port has a first cross-sectional area and when the air flow rate is a second flow rate that is lower than the first flow rate, the outlet port has a second cross-sectional area that is smaller than the first cross-sectional area. 
         9. The surface cleaning apparatus of clause 8 wherein the cross-section area is automatically varied based on the air flow rate. 
         10. The surface cleaning apparatus of clause 8 wherein the surface cleaning apparatus comprises:
       (a) a floor cleaning unit comprising a surface cleaning head and upright support member moveably mounted between an upright storage position and a reclined cleaning position; and,   (b) a portable surface cleaning unit comprising the air treatment chamber and the suction motor,   
     
       
    
     wherein the portable cleaning unit is removably mountable to the floor cleaning unit whereby, when the portable cleaning unit is mounted to the floor cleaning unit, the surface cleaning apparatus is operable in an upright vacuum cleaner mode and, when the portable cleaning unit is removed from the floor cleaning unit, the portable cleaning unit is operable in an above floor cleaning mode, and 
     wherein, when the surface cleaning apparatus is operated in the upright vacuum cleaner mode, the air flow rate is the second flow rate and when the portable cleaning unit is operated in the above floor cleaning mode, the air flow rate is the first flow rate.
     11. The surface cleaning apparatus of clause 10 wherein the cross-section area is automatically varied as an operating mode of the surface cleaning apparatus is changed from the upright vacuum cleaner mode to the above floor cleaning mode.   12. The surface cleaning apparatus of clause 1 wherein, when a first power level is provided to the suction motor, the outlet port has a first cross-sectional area and, when a second power level is provided to the suction motor wherein the second power level is lower than the first power level, the outlet port has a second cross-sectional area that is smaller than the first cross-sectional area.   13. The surface cleaning apparatus of clause 12 wherein the cross-section area is automatically varied based on the power level.   14. The surface cleaning apparatus of clause 12 wherein the surface cleaning apparatus comprises:
       (a) a floor cleaning unit comprising a surface cleaning head and upright support member moveably mounted between an upright storage position and a reclined cleaning position; and,   (b) a portable surface cleaning unit comprising the air treatment chamber and the suction motor,   
       

     wherein the portable cleaning unit is removably mountable to the floor cleaning unit whereby, when the portable cleaning unit is mounted to the floor cleaning unit, the surface cleaning apparatus is operable in an upright vacuum cleaner mode and, when the portable cleaning unit is removed from the floor cleaning unit, the portable cleaning unit is operable in an above floor cleaning mode, and 
     wherein, when the surface cleaning apparatus is operated in the upright vacuum cleaner mode, the suction motor has provided to it the second power level and when the portable cleaning unit is operated in the above floor cleaning mode, the suction motor has provided to it the first power level.
     15. The surface cleaning apparatus of clause 14 wherein the power level is automatically varied as an operating mode of the surface cleaning apparatus is changed from the upright vacuum cleaner mode to the above floor cleaning mode.   

     The surface cleaning apparatus of clause 1 wherein the cross-sectional area of the outlet port is varied based on the size of dirt which is collected.
     16. The surface cleaning apparatus of clause 16 wherein, when the dirt having a first size is collected, the outlet port has a first cross-sectional area and when the dirt having a second size that is smaller than the first size is collected, the outlet port has a second cross-sectional area that is smaller than the first cross-sectional area.   17. The surface cleaning apparatus of clause 17 wherein the cross-sectional area of the outlet port is automatically varied based on the size of the dirt which is collected.   18. The surface cleaning apparatus of clause 17 wherein the cross-sectional area of the outlet port is manually varied.   

     Clause Set C 
     
         
         1. A surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment member provided in the air flow path, the air treatment member comprising an air treatment chamber having an air treatment chamber air inlet and an air treatment chamber air outlet, wherein the air treatment chamber air inlet comprises a portion in which air flows therethrough in a flow direction;   (c) a closure member which is moveable in the flow direction between an open position in which, during operation of the surface cleaning apparatus, air flows through the air treatment chamber air inlet to the air treatment chamber, and a closed position in which air flow through the air treatment chamber air inlet is inhibited; and,   (d) a motor and fan assembly provided in the air flow path.   
     
         2. The surface cleaning apparatus of clause 1 wherein the flow direction is axial. 
         3. The surface cleaning apparatus of clause 1 wherein the air treatment member has a first end and a second end, wherein the second end is spaced apart from the first end in the flow direction. 
         4. The surface cleaning apparatus of clause 3 wherein the air treatment chamber air inlet has an inlet end and an outlet end and the closure member moves in a direction opposite to the flow direction from the open position, through the inlet conduit, towards the inlet end of the conduit to the closed position. 
         5. The surface cleaning apparatus of clause 4 wherein the inlet end of the inlet conduit has an inlet port and, in the closed position, the closure member abuts the inlet port. 
         6. The surface cleaning apparatus of clause 4 wherein the inlet conduit has a sidewall that extends in the flow direction and the outlet end has an outlet port provided in the sidewall, the closure member comprises an end wall that extends transverse to the flow direction. 
         7. The surface cleaning apparatus of clause 6 wherein the inlet conduit removably receives an upstream air flow conduit and insertion of the upstream air flow conduit into the inlet conduit moves the closure member from the closed position to the open position. 
         8. The surface cleaning apparatus of clause 7 wherein the closure member is biased to the closed position. 
         9. The surface cleaning apparatus of clause 1 wherein the closure member moves along a rail from the closed position to the open position 
         10. The surface cleaning apparatus of clause 1 wherein the surface cleaning apparatus comprises:
       (a) a floor cleaning unit comprising a surface cleaning head; and   (b) a portable surface cleaning unit comprising the air treatment chamber and the suction motor.   
     
       
    
     wherein the portable cleaning unit is removably mountable to the floor cleaning unit whereby, when the portable cleaning unit is mounted to the floor cleaning unit, the surface cleaning apparatus is operable in a floor cleaner mode and, when the portable cleaning unit is removed from the floor cleaning unit, the portable cleaning unit is operable in an above floor cleaning mode, and wherein, mounting the portable cleaning unit to the floor cleaning unit moves the closure member from the closed position to the open position.
     11. The surface cleaning apparatus of clause 10 wherein the closure member is biased to the closed position.   12. The surface cleaning apparatus of clause 1 wherein the air treatment member has a first end and a second end, wherein the second end is spaced apart from the first end in an axial direction, the air treatment member has an axial extending sidewall and the air treatment chamber air inlet is provided in the sidewall.   13. The surface cleaning apparatus of clause 12 wherein the sidewall of the air treatment member is curved in a plane transverse to the axial direction and the closure member moves in the axial direction between the open and closed positions.   14. The surface cleaning apparatus of clause 13 wherein the closure member is curved in the plane transverse to the axial direction.   15. The surface cleaning apparatus of clause 1 further comprising an on/off actuator which is operable to actuate the suction motor when the actuator is set to on and which is operable to deenergize the suction motor when the actuator is set to off, and the closure member moves from the open position to the closed position in response to the actuator being set to off.   16. The surface cleaning apparatus of clause 15 wherein on/off actuator is mechanically drivingly connected to the closure member.   17. The surface cleaning apparatus of clause 15 wherein when the on/off actuator is transitioned to off, a signal is issued which causes an electromechanical member to drive the closure member to the closed position.   18. The surface cleaning apparatus of clause 1 wherein suction produced by the suction motor moves the closure member from the closed position to the open position.   

     Clause Set D 
     
         
         1. A surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet, the air flow path comprising an air treatment member;   (b) the air treatment member comprising an air treatment chamber having a first end, a second end, a sidewall extending between the first and second ends, a central axis extending from the first end to the second end through a center of the air treatment chamber, an air treatment chamber air inlet and an air treatment chamber air outlet:   (c) a closure member which is moveable between an open position in which at least a portion of the closure member is exterior to the air flow path whereby, during operation of the surface cleaning apparatus, air flows through the air treatment chamber air inlet to the air treatment chamber, and a closed position in which air flow through the air treatment chamber air inlet is inhibited: and,   (d) a motor and fan assembly provided in the air flow path.   
     
         2. The surface cleaning apparatus of clause 1 wherein, in the closed position, the at least a portion of the closure member closes a port in a wall of the air treatment chamber. 
         3. The surface cleaning apparatus of clause 1 wherein, in the open position, the at least a portion of the closure member forms a portion of the wall of the air flow path. 
         4. The surface cleaning apparatus of clause 3 wherein the air treatment chamber has a first end and a second end, wherein the second end is spaced apart from the first end in an axial direction, the air treatment chamber has an axial extending sidewall, the sidewall has a port that communicates with the pocket and the port is closed by the closure member when the closure member is in the open position. 
         5. The surface cleaning apparatus of clause 1 wherein the air treatment chamber has a first end and a second end, wherein the second end is spaced apart from the first end in an axial direction, the air treatment chamber has an axial extending sidewall, the sidewall has a port that communicates with the pocket and the port is closed by the closure member when the closure member is in the open position. 
         6. The surface cleaning apparatus of clause 1 further comprising a pocket that is exterior to the air treatment chamber and, when the closure member is in the open position, the at least a portion of the closure member is positioned in the pocket. 
         7. The surface cleaning apparatus of clause 1 further comprising a rotational axis whereby the closure member is rotatably moveable between the open position and the closed position, and the rotation axis is generally perpendicular to the central axis. 
         8. The surface cleaning apparatus of clause 7 wherein the closure member is planar. 
         9. The surface cleaning apparatus of clause 7 wherein the air treatment chamber air inlet is provided at the first end of the air treatment chamber, the closure member has a first end comprising a rotational mount and a second opposed end, the closure member extends generally perpendicular to the central axis when in the closed position and the second opposed end of the closure member rotates towards the second end of the air treatment chamber as the closure member moves to the open position. 
         10. The surface cleaning apparatus of clause 7 wherein the rotation axis is exterior to the air treatment chamber. 
         11. The surface cleaning apparatus of clause 1 further comprising a rotational axis whereby the closure member is rotatably moveable between the open position and the closed position, and the rotation axis is generally parallel to the central axis and spaced from the central axis in a direction transverse to the central axis. 
         12. The surface cleaning apparatus of clause 11 wherein the closure member is arcuate in shape. 
         13. The surface cleaning apparatus of clause 11 wherein the closure member has a profile in a plane that is transverse to the central axis that is similar to a profile of the sidewall in the plane. 
         14. The surface cleaning apparatus of clause  11  wherein the rotation axis is exterior to the air treatment chamber. 
         15. The surface cleaning apparatus of clause 1 further comprising an on/off actuator which is operable to actuate the suction motor when the actuator is set to on and which is operable to deenergize the suction motor when the actuator is set to off, and the closure member moves from the open position to the closed position in response to the actuator being set to off. 
         16. The surface cleaning apparatus of clause 15 wherein on/off actuator is mechanically drivingly connected to the closure member. 
         17. The surface cleaning apparatus of clause 15 wherein when the on/off actuator is transitioned to off a signal is issued which causes an electromechanical member to drive the closure member to the closed position. 
         18. The surface cleaning apparatus of clause 1 wherein suction produced by the suction motor moves the closure member from the closed position to the open position. 
         19. The surface cleaning apparatus of clause 1 wherein the surface cleaning apparatus comprises:
       (a) a floor cleaning unit comprising a surface cleaning head; and   (b) a portable surface cleaning unit comprising the air treatment chamber and the suction motor.   wherein the portable cleaning unit is removably mountable to the floor cleaning unit whereby, when the portable cleaning unit is mounted to the floor cleaning unit, the surface cleaning apparatus is operable in a floor cleaner mode and, when the portable cleaning unit is removed from the floor cleaning unit, the portable cleaning unit is operable in an above floor cleaning mode, and wherein, mounting the portable cleaning unit to the floor cleaning unit moves the closure member from the closed position to the open position.  20 . The surface cleaning apparatus of clause 1 wherein the air treatment chamber comprises a cyclone chamber and the central axis is a cyclone axis of rotation.   
     
       
    
     Clause Set E 
     
         
         1. A surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment member provided in the air flow path, the air treatment member comprising an air treatment chamber having a first end, a second end, a sidewall extending between the first and second ends, a central axis extending from the first end to the second end through a center of the air treatment chamber, an air treatment chamber air inlet and an air treatment chamber air outlet;   (c) a closure member which is moveable between an open position in which, during operation of the surface cleaning apparatus, air flows through the air treatment chamber air inlet to the air treatment chamber, and a closed position in which air flow through the air treatment chamber air inlet is inhibited:   (d) a driving member driving connected to the closure member; and.   (e) a motor and fan assembly provided in the air flow path   
     
       
    
     wherein the closure member moves in a first direction from the open position to the closed position and in a second direction from the closed position to the open position, and the driving member is operable to move the closure member in at least one of the first and second directions.
     2. The surface cleaning apparatus of clause 1 wherein the driving member is operable to move the closure member in the first direction and in the second direction.   3. The surface cleaning apparatus of clause 1 further comprising an on/off actuator which is operable to actuate the suction motor when the actuator is set to on and which is operable to deenergize the suction motor when the actuator is set to off, and the driving member moves the closure member from the open position to the closed position in response to the actuator being set to off.   4. The surface cleaning apparatus of clause 3 wherein the driving member comprises a mechanical driving linkage whereby the on/off actuator is mechanically drivingly connected to the closure member mechanical driving linkage.   5. The surface cleaning apparatus of clause 3 wherein the driving member comprises an electromechanical member whereby when the on/off actuator is transitioned to off, a signal is issued which causes an electromechanical member to drive the closure member to the closed position.   6. The surface cleaning apparatus of clause 5 wherein the electromechanical member comprises a solenoid.   7. The surface cleaning apparatus of clause 3 wherein the closure member moves from the closed position to the open position in response to the actuator being set to on.   8. The surface cleaning apparatus of clause 1 wherein suction produced by the suction motor moves the driving member which moves the closure member from the closed position to the open position.   9. The surface cleaning apparatus of clause 7 wherein the driving member comprises a piston.   10. The surface cleaning apparatus of clause 7 wherein the closure member is biased to the closed position.   11. The surface cleaning apparatus of clause 1 wherein the driving member comprises a rigid air flow conduit that is removably insertable into the dirty air inlet whereby insertion of the rigid air flow conduit moves the closure member from the closed position to the open position.   12. The surface cleaning apparatus of clause 11 wherein the closure member s biased to the closed position.   13. The surface cleaning apparatus of clause 1 wherein a rigid air flow conduit is removably insertable into the dirty air inlet and the driving member comprises an engagement member provided on the rigid air flow conduit and an actuator that is operatively connected to the closure member whereby upon insertion of the rigid air flow conduit into the dirty air inlet, the engagement member contacts the actuator which moves the closure member from the closed position to the open position.   14. The surface cleaning apparatus of clause 13 wherein the actuator comprises a mating engagement member that is drivingly connected to the closure member.   15. The surface cleaning apparatus of clause 13 wherein the actuator comprises an electromechanical member.   15. The surface cleaning apparatus of clause 1 wherein the surface cleaning apparatus comprises:
       (a) a floor cleaning unit comprising a surface cleaning head; and   (b) a portable surface cleaning unit comprising the air treatment chamber and the suction motor.   
       

     wherein the portable cleaning unit is removably mountable to the floor cleaning unit whereby, when the portable cleaning unit is mounted to the floor cleaning unit, the surface cleaning apparatus is operable in a floor cleaner mode and, when the portable cleaning unit is removed from the floor cleaning unit, the portable cleaning unit is operable in an above floor cleaning mode, and 
     wherein, mounting the portable cleaning unit to the floor cleaning unit moves the closure member from the closed position to the open position.
     17. The surface cleaning apparatus of clause 16 wherein the floor cleaning unit comprises a rigid air flow conduit that is removably insertable into the portable surface cleaning unit, and the driving member comprises the rigid air flow conduit.   18. The surface cleaning apparatus of clause 17 wherein the driving member comprises an engagement member provided on the rigid air flow conduit and an actuator that is operatively connected to the closure member whereby upon insertion of the rigid air flow conduit into the portable surface cleaning unit, the engagement member contacts the actuator which moves the closure member from the closed position to the open position.   19. The surface cleaning apparatus of clause 16 wherein the driving member comprises an engagement member provided on the floor cleaning unit and an actuator that is operatively connected to the closure member whereby upon mounting the portable cleaning unit to the floor cleaning unit, the engagement member contacts the actuator which moves the closure member from the closed position to the open position.   

     Clause Set F 
     
         
         1. A hand surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) a cyclone provided in the air flow path, the cyclone comprising a cyclone chamber having a first end a second end, a sidewall extending between the first and second ends, a cyclone axis of rotation extending from the first end to the second end, a cyclone air inlet provided at the first end and a cyclone air outlet provided at the second end, the cyclone air outlet comprises an air impermeable portion and a porous portion; and,   (c) a motor and fan assembly provided in the air flow path wherein a rib, which is positioned between the cyclone air outlet and the sidewall, extends in a generally axial direction, and   
     
       
    
     wherein the rib extends co-extensively along at least a portion of the cyclone chamber in which the impermeable portion is provided.
     2. The surface cleaning apparatus of clause 1 wherein a plurality of ribs is provided and the ribs are angularly spaced apart around the cyclone air outlet.   3. The surface cleaning apparatus of clause 1 wherein the second end comprises a second end wall, and the rib extends inwardly into the cyclone chamber from the second end wall.   4. The surface cleaning apparatus of clause 1 wherein the second end comprises a second end wall, the impermeable portion extends inwardly into the cyclone chamber and has an inner end, the porous portion has an outward end located at the inner end of the impermeable portion, the porous portion extends further inwardly into the cyclone chamber from the inner end of the impermeable portion, the rib has a first side that is closer to the first end than the second end and the first side is positioned prior to the outward end.   5. The surface cleaning apparatus of clause 4 wherein the first end of the rib is curved.   6. The surface cleaning apparatus of clause 1 wherein the rib extends co-extensive only with the porous portion.   7. The surface cleaning apparatus of clause 1 wherein the rib has a first side that is closer to the first end than the second end and the first end of the rib is cured.   8. A surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet:   (b) a cyclone provided in the air flow path, the cyclone comprising a cyclone chamber having a first end, a second end, a sidewall extending between the first and second ends, a cyclone axis of rotation extending from the first end to the second end, a cyclone air inlet and a cyclone air outlet provided at the second end: and,   (c) a motor and fan assembly provided in the air flow path   
       

     wherein a rib, which is positioned between the cyclone air outlet and the sidewall, extends in a generally axial direction.
     9. The surface cleaning apparatus of clause 8 wherein a plurality of ribs is provided and the ribs are angularly spaced apart around the cyclone air outlet.   10. The surface cleaning apparatus of clause 8 wherein the cyclone air outlet comprises an air impermeable portion and a porous portion, and the rib extends co-extensively along at least a portion of the cyclone chamber in which the impermeable portion is provided.   11. The surface cleaning apparatus of clause 10 wherein the second end comprises a second end wall, the impermeable portion extends inwardly into the cyclone chamber and has an inner end, the porous portion has an outward end located at the inner end of the impermeable portion, the porous portion extends further inwardly into the cyclone chamber from the inner end of the impermeable portion, the rib has a first side that is closer to the first end than the second end and the first side is positioned prior to the outward end.   12. The surface cleaning apparatus of clause 10 wherein the rib extends co-extensive only with the porous portion.   7. The surface cleaning apparatus of clause 11 wherein the first end of the rib is curved.   14. The surface cleaning apparatus of clause 12 wherein the first end of the rib is curved.   15. The surface cleaning apparatus of clause 8 wherein the rib has a first side that is closer to the first end than the second end and the first end of the rib is curved.   16. The surface cleaning apparatus of clause 15 wherein the second end comprises a second end wall, and the rib extends inwardly into the cyclone chamber from the second end wall.   17. The surface cleaning apparatus of clause 8 wherein the second end comprises a second end wall, and the rib extends inwardly into the cyclone chamber from the second end wall.   18. The surface cleaning apparatus of clause 8 wherein the cyclone air inlet is provided at the first end.   19. The surface cleaning apparatus of clause 18 wherein the surface cleaning apparatus is a hand surface cleaning apparatus, the first end is a front end of the cyclone and the second end is a rear end of the cyclone.   

     Clause Set G 
     
         
         1. A surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment member provided in the air flow path, the air treatment member comprising an air treatment chamber comprising an air treatment chamber housing having a central axis that extends from a first end of the air treatment chamber housing to an axially spaced apart second end of the air treatment chamber housing through a center of the air treatment chamber, a sidewall extending between the first and second ends, an air treatment chamber air inlet and an air treatment chamber air outlet provided at the second end, at least a portion of the first end of the air treatment chamber housing is moveable between a closed operating position and an open position in which a first end of the air treatment chamber is opened; and,   (c) a motor and fan assembly provided in the air flow path,   
     
       
    
     wherein the air treatment chamber is emptyable by opening the first end of the air treatment chamber housing and moving at least a portion of the second end axially towards the first end of the air treatment chamber.
     2. The surface cleaning apparatus of clause 1 wherein the at least a portion of the second end is moved axially towards the first end of the air treatment chamber subsequent to the first end of the air treatment chamber housing being opened.   3. The surface cleaning apparatus of clause 1 wherein the at least a portion of the second end is moved axially towards the first end of the air treatment chamber as the first end of the air treatment chamber housing is opened.   4. The surface cleaning apparatus of clause 1 wherein the air treatment chamber air outlet comprises a porous member and the at least a portion of the second end comprises the porous member.   5. The surface cleaning apparatus of clause 1 wherein the second end comprises a second end wall and the at least a portion of the second end comprises a portion of the second end wall.   6. The surface cleaning apparatus of clause 1 wherein the air treatment chamber air outlet comprises a porous member and the second end comprises a second end wall and the at least a portion of the second end comprises the second end wall and the porous member.   7. The surface cleaning apparatus of clause 1 further comprising a track and the at least a portion of the second end is slidable axially along the track.   8. The surface cleaning apparatus of clause 7 wherein the track has an associated felt sealing member.   9. The surface cleaning apparatus of clause 7 wherein the track is provided in the sidewall.   10. The surface cleaning apparatus of clause 1 further comprising a pre-motor filter and the pre-motor filter is moveable with the at least a portion of the second end.   11. The surface cleaning apparatus of clause 1 wherein the first end of the air treatment chamber housing translates forwardly from the closed position to the open position.   12. The surface cleaning apparatus of clause 1 wherein the first end of the air treatment member housing is drivingly connected to the at least a portion of the second end by a linking member.   13. The surface cleaning apparatus of clause 12 wherein the linking member is a mechanical linkage.   14. The surface cleaning apparatus of clause 12 wherein the linking member comprises an electromechanical member.   15. The surface cleaning apparatus of clause 1 wherein operation of the suction motor produces an air flow that moves the at least a portion of the second end.   16. The surface cleaning apparatus of clause 1 wherein the first end comprises a first end wall and the at least a portion of the first end of the air treatment chamber housing comprises the first end wall.   17. The surface cleaning apparatus of clause 16 wherein the surface cleaning apparatus is a hand vacuum cleaner and the dirty air inlet is moveable with the first end wall.   18. The surface cleaning apparatus of clause 16 wherein the air treatment member further comprises an inlet conduit and the inlet conduit is moveable with the first end wall.   

     Clause Set H 
     
         
         1. A surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment member provided in the air flow path, the air treatment member comprising an air treatment chamber comprising an air treatment chamber housing having a central axis that extends from a first end of the air treatment chamber housing to an axially spaced apart second end of the air treatment chamber housing through a center of the air treatment chamber, a sidewall extending between the first and second ends, an air treatment chamber air inlet and an air treatment chamber air outlet provided at the second end, an openable portion of the air treatment chamber housing is moveable between a closed operating position and an open position in which the air treatment chamber is opened; and,   (c) a motor and fan assembly provided in the air flow path.   
     
       
    
     wherein the at least a portion of the second end is moveably mounted, and the at least a portion of the second end is moved as the air treatment chamber housing is opened.
     2. The surface cleaning apparatus of clause 1 wherein the openable portion of the air treatment chamber housing comprises at least a portion of the first end of the air treatment chamber housing.   3. The surface cleaning apparatus of clause 2 wherein at least a portion of the second end is moved axially towards the first end of the air treatment chamber as the air treatment chamber housing is opened.   4. The surface cleaning apparatus of clause 1 wherein at least a portion of the second end is moved towards an open portion of the air treatment chamber as the air treatment chamber housing is opened.   5. The surface cleaning apparatus of clause 1 wherein the air treatment chamber air outlet comprises a porous member and the at least a portion of the second end comprises the porous member.   6. The surface cleaning apparatus of clause 1 wherein the second end comprises a second end wall and the at least a portion of the second end comprises a portion of the second end wall.   7. The surface cleaning apparatus of clause 1 wherein the air treatment chamber air outlet comprises a porous member and the second end comprises a second end wall and the at least a portion of the second end comprises the second end wall and the porous member.   8. The surface cleaning apparatus of clause 1 further comprising a track and the at least a portion of the second end is slidable axially along the track.   9. The surface cleaning apparatus of clause 8 wherein the track has an associated felt sealing member.   10. The surface cleaning apparatus of clause 8 wherein the track is provided in the sidewall.   11. The surface cleaning apparatus of clause 1 further comprising a pre-motor filter and the pre-motor filter is moveable with the at least a portion of the second end.   12. The surface cleaning apparatus of clause 1 wherein the first end of the air treatment chamber housing translates forwardly from the closed position to the open position.   13. The surface cleaning apparatus of clause 1 wherein the openable portion of the air treatment chamber housing is drivingly connected to the at least a portion of the second end by a linking member.   14. The surface cleaning apparatus of clause 13 wherein the linking member is a mechanical linkage.   15. The surface cleaning apparatus of clause 13 wherein the linking member comprises an electromechanical member.   16. The surface cleaning apparatus of clause 1 wherein operation of the suction motor produces an air flow that moves the at least a portion of the second end.   17. The surface cleaning apparatus of clause 1 wherein the surface cleaning apparatus is a hand vacuum cleaner and the dirty air inlet is moveable with the openable portion.   18. The surface cleaning apparatus of clause 1 wherein the air treatment member further comprises an inlet conduit and the inlet conduit is moveable with the openable portion.   

     Clause Set I 
     
         
         1. A surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment member provided in the air flow path, the air treatment member comprising an air treatment chamber comprising an air treatment chamber housing having a central axis that extends from a first end of the air treatment chamber housing to an axially spaced apart second end of the air treatment chamber housing through a center of the air treatment chamber, a sidewall extending between the first and second ends, an air treatment chamber air inlet and an air treatment chamber air outlet provided at the second end, at least a portion of the first end of the air treatment chamber housing is moveable between a closed operating position and an open position in which a first end of the air treatment chamber is opened, wherein at least a portion of the first end of the air treatment chamber housing translates forwardly from the closed position to the open position; and,   (c) a motor and fan assembly provided in the air flow path.   
     
         2. The surface cleaning apparatus of clause 1 wherein the first end comprises a first end wall and the at least a portion of the first end of the air treatment chamber housing comprises the first end wall. 
         3. The surface cleaning apparatus of clause 2 wherein the surface cleaning apparatus is a hand vacuum cleaner and the dirty air inlet is moveable with the first end wall. 
         4. The surface cleaning apparatus of clause 2 wherein the air treatment member further comprises an inlet conduit and the inlet conduit is moveable with the first end wall. 
         5. The surface cleaning apparatus of clause 1 wherein at least a portion of the second end is moveably mounted, and the at least a portion of the second end is moved as the air treatment chamber housing is opened 
         6. The surface cleaning apparatus of clause 5 wherein the at least a portion of the second end is moveable axially. 
         7. The surface cleaning apparatus of clause 5 wherein the at least a portion of the second end is moved subsequent to the first end of the air treatment chamber housing translating forwardly. 
         8. The surface cleaning apparatus of clause 5 wherein the at least a portion of the second end is moved as the first end of the air treatment chamber housing translates forwardly. 
         9. The surface cleaning apparatus of clause 5 wherein the air treatment chamber air outlet comprises a porous member and the at least a portion of the second end comprises the porous member. 
         10. The surface cleaning apparatus of clause 5 wherein the second end comprises a second end wall and the at least a portion of the second end comprises a portion of the second end wall. 
         11. The surface cleaning apparatus of clause 5 wherein the air treatment chamber air outlet comprises a porous member and the second end comprises a second end wall and the at least a portion of the second end comprises the second end wall and the porous member. 
         12. The surface cleaning apparatus of clause 5 further comprising a track and the at least a portion of the second end is slidable axially along the track. 
         13. The surface cleaning apparatus of clause 12 wherein the track has an associated felt sealing member. 
         14. The surface cleaning apparatus of clause 12 wherein the track is provided in the sidewall. 
         15. The surface cleaning apparatus of clause 5 further comprising a pre-motor filter and the pre-motor filter is moveable with the at least a portion of the second end. 
         16. The surface cleaning apparatus of clause 5 wherein the first end of the air treatment member housing is drivingly connected to the at least a portion of the second end by a linking member. 
         17. The surface cleaning apparatus of clause 16 wherein the linking member is a mechanical linkage. 
         18. The surface cleaning apparatus of clause 16 wherein the linking member comprises an electromechanical member. 
         19. The surface cleaning apparatus of clause 5 wherein operation of the suction motor produces an air flow that moves the at least a portion of the second end. 
       
    
     Clause Set J 
     
         
         1. A surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment member provided in the air flow path, the air treatment member comprising an air treatment chamber comprising an air treatment chamber housing having a central axis that extends from a first end of the air treatment chamber housing to an axially spaced apart second end of the air treatment chamber housing through a center of the air treatment chamber, a sidewall extending between the first and second ends, an air treatment chamber air inlet and an air treatment chamber air outlet provided at the second end, an openable portion of the air treatment chamber housing is moveable between a closed operating position and an open position in which the air treatment chamber is opened; and,   (c) a motor and fan assembly provided in the air flow path.   
     
       
    
     wherein at least a portion of the second end is moveably mounted, and wherein operation of the suction motor produces an air flow that moves the at least a portion of the second end.
     2. The surface cleaning apparatus of clause 1 wherein the openable portion of the air treatment chamber housing comprises at least a portion of the first end of the air treatment chamber housing.   3. The surface cleaning apparatus of clause 2 wherein at least a portion of the second end is moved axially towards the first end of the air treatment chamber as the air treatment chamber housing is opened.   4. The surface cleaning apparatus of clause 1 wherein the at least a portion of the first end of the air treatment chamber housing is translatable forwardly from the closed position to the open position.   5. The surface cleaning apparatus of clause 1 wherein at least a portion of the second end is moved towards an open portion of the air treatment chamber as the air treatment chamber housing is opened.   6. The surface cleaning apparatus of clause 1 wherein the air treatment chamber air outlet comprises a porous member and the at least a portion of the second end comprises the porous member.   7. The surface cleaning apparatus of clause 1 wherein the second end comprises a second end wall and the at least a portion of the second end comprises a portion of the second end wall.   8. The surface cleaning apparatus of clause 1 wherein the air treatment chamber air outlet comprises a porous member and the second end comprises a second end wall and the at least a portion of the second end comprises the second end wall and the porous member.   9. The surface cleaning apparatus of clause 1 further comprising a track and the at least a portion of the second end is slidable axially along the track.   10. The surface cleaning apparatus of clause 10 wherein the track has an associated felt sealing member.   11. The surface cleaning apparatus of clause 10 wherein the track is provided in the sidewall.   12. The surface cleaning apparatus of clause 1 further comprising a pre-motor filter and the pre-motor filter is moveable with the at least a portion of the second end.   13. The surface cleaning apparatus of clause 1 wherein the suction motor is actuated to produce the air flow that moves the at least a portion of the second end upon the operable portion opening.   14. The surface cleaning apparatus of clause 1 wherein the suction motor is actuated to produce the air flow that moves the at least a portion of the second end upon the surface cleaning apparatus docking at a docking station.   15. The surface cleaning apparatus of clause 1 wherein the suction motor is actuated to produce the air flow that moves the at least a portion of the second end upon the air treatment member docking at a docking station.   

     Clause Set K 
     A hand surface cleaning apparatus having a front end and a rear end, the hand surface cleaning apparatus comprising:
         (a) an air flow path from a dirty air inlet to a clean air outlet:   (b) an air treatment member provided in the air flow path:   (c) a motor and fan assembly provided in the air flow path; and   (d) a user interface that is spaced from and overlies the rear end of the hand surface cleaning apparatus.       2. The hand surface cleaning apparatus of clause 1 further comprising a support arm, the support arm has a user interface support that is spaced from and overlies the rear end of the hand surface cleaning apparatus.   3. The hand surface cleaning apparatus of clause 2 wherein the user interface support faces rearwardly.   4. The hand surface cleaning apparatus of clause 2 further comprising an air gap provided between a rear end of a main body of the hand surface cleaning apparatus and the user interface support.   5. The hand surface cleaning apparatus of clause 4 further comprising a fan and suction motor housing and the rear end is a rear end of the fan and suction motor housing.   6. The hand surface cleaning apparatus of clause 1 wherein the support arm extends rearwardly from the rear end.   7. The hand surface cleaning apparatus of clause 1 further comprising a pistol grip handle that is provided on a lower end of the hand surface cleaning apparatus and the support arm extends rearwardly from the pistol grip handle.   8. The hand surface cleaning apparatus of clause 7 wherein the support arm extends rearwardly from an upper end of the pistol grip handle.   9. The hand surface cleaning apparatus of clause 7 further comprising an energy storage member provided at a lower end of the pistol grip handle.   10. The hand surface cleaning apparatus of clause 1 wherein the user interface provides information about at least one operating mode of the hand surface cleaning apparatus.   11. The hand surface cleaning apparatus of clause 1 further comprising an energy storage member and the user interface provides information about a charge level of the energy storage member.   12. The hand surface cleaning apparatus of clause 1 wherein the user interface includes at least one control of the hand surface cleaning apparatus.   13. A hand surface cleaning apparatus having a front end and a rear end, the hand surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment member provided in the air flow path;   (c) a motor and fan assembly provided in the air flow path;   (d) a pistol grip handle, wherein an upper end of the pistol grip handle is mounted to a lower end of the hand surface cleaning apparatus; and,   (e) a user interface provided on the handle, wherein the user interface provides information about at least one operating mode of the hand surface cleaning apparatus.   
       14. The hand surface cleaning apparatus of clause 13 wherein the user interface includes at least one control of the hand surface cleaning apparatus.   15. The hand surface cleaning apparatus of clause 13 further comprising an energy storage member provided at a lower end of the pistol grip handle.   16. The hand surface cleaning apparatus of clause 15 wherein the user interface is provided at an upper end of the pistol grip handle.   17. The hand surface cleaning apparatus of clause 13 further comprising an energy storage member and the user interface provides information about a charge level of the energy storage member.   18. The hand surface cleaning apparatus of clause 1 wherein the user interface provides information about at least one operating mode of the hand surface cleaning apparatus.   19. A hand surface cleaning apparatus having a front end and a rear end, the hand surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment member provided in the air flow paths.   (c) a motor and fan assembly provided in the air flow path;   (d) a pistol grip handle, wherein an upper end of the pistol grip handle is mounted to a lower end of the hand surface cleaning apparatus; and,   (e) a user interface provided on the handle, wherein the user interface is provided at an upper end of the pistol grip handle.   
       20. The hand surface cleaning apparatus of clause 19 wherein the user interface includes at least one control of the hand surface cleaning apparatus.   21. The hand surface cleaning apparatus of clause 19 further comprising an energy storage member provided at a lower end of the pistol grip handle.   22. The hand surface cleaning apparatus of clause 19 further comprising an energy storage member and the user interface also provides information about a charge level of the energy storage member.   

     Clause Set L 
     
         
         1. A hand surface cleaning apparatus having a front end and a rear end, the hand surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment member provided in the air flow path;   (c) a motor and fan assembly provided in the air flow path;   (d) a filter provided at the rear end of the hand surface cleaning apparatus; and   (e) a user interface provided at the rear end of the hand surface cleaning apparatus,   
     
       
    
     wherein the filter is removable rearwardly.
     2. The hand surface cleaning apparatus of clause 1 wherein the user interface remains in position when the filter is removed.   3. The hand surface cleaning apparatus of clause 1 wherein the rear end comprises a rear wall and the rear wall is part of a filter housing.   4. The hand surface cleaning apparatus of clause 1 wherein the user interface is positioned radially outwardly of the filter.   5. The hand surface cleaning apparatus of clause 1 further comprising a filter housing and the user interface is positioned radially outwardly of the filter housing.   6. The hand surface cleaning apparatus of clause 1 further comprising a filter housing and the user interface is part of the filter housing.   7. The hand surface cleaning apparatus of clause 1 wherein the rear end of the hand vacuum cleaner comprises an annular portion and the user interface is provided on the annular portion.   8. The hand surface cleaning apparatus of clause 7 wherein the user interface comprises an annulus sector of the annular portion.   9. The hand surface cleaning apparatus of clause 7 wherein the user interface comprises a display surface that faces radially outwardly.   10. The hand surface cleaning apparatus of clause 7 wherein the user interface comprises a display surface that faces rearwardly.   11. The hand surface cleaning apparatus of clause 1 wherein the user erface comprises a display surface that faces radially outwardly.   12. The hand surface cleaning apparatus of clause 1 wherein the user interface comprises a display surface that faces rearwardly.   13. The hand surface cleaning apparatus of clause 1 wherein the user interface provides information about at least one operating mode of the hand surface cleaning apparatus.   14. The hand surface cleaning apparatus of clause 13 wherein the user interface includes at least one control of the hand surface cleaning apparatus.   15. The hand surface cleaning apparatus of clause 13 further comprising an energy storage member and the user interface also provides information about a charge level of the energy storage member.   16. A hand surface cleaning apparatus having a front end and a rear end, the hand surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet:   (b) an air treatment member provided in the air flow path;   (c) a motor and fan assembly provided in the air flow path;   (d) a filter provided at the rear end of the hand surface cleaning apparatus; and   (e) a user interface provided at the rear end of the hand surface cleaning apparatus,   
       

     wherein the rear end of the hand vacuum cleaner comprises an annular portion and the user interface is provided on the annular portion.
     17. The hand surface cleaning apparatus of clause 16 wherein the user interface comprises an annulus sector of the annular portion.   18. The hand surface cleaning apparatus of clause 16 wherein the user interface comprises a display surface that faces radially outwardly.   19. The hand surface cleaning apparatus of clause 16 wherein the user interface comprises a display surface that faces rearwardly.   20. The hand surface cleaning apparatus of clause 16 wherein the user interface provides information about at least one operating mode of the hand surface cleaning apparatus.   21. The hand surface cleaning apparatus of clause 20 wherein the user interface includes at least one control of the hand surface cleaning apparatus.   22. The hand surface cleaning apparatus of clause 20 further comprising an energy storage member and the user interface also provides information about a charge level of the energy storage member.   

     Clause Set M 
     
         
         1. A hand surface cleaning apparatus having a front end and a rear end, the hand surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet;   (b) an air treatment chamber provided in the air flow path, the air treatment chamber comprising a front end, a rear end, an air treatment chamber air inlet and an air treatment chamber air outlet, the air treatment chamber air outlet comprising a rigid porous member   (c) a rigid frustoconical premotor filter that is at least partially nested in the porous member, the premotor filter comprises a pleated filter material; and,   (d) a motor and fan assembly provided in the air flow path.   
     
         2. The hand surface cleaning apparatus of clause 1 wherein the air treatment chamber comprises a cyclone having a cyclone axis of rotation wherein the cyclone axis of rotation extends through the front and rear ends of the hand vacuum cleaner. 
         3. The hand surface cleaning apparatus of clause 1 wherein the pleats extend in a forward/rearward direction. 
         4. The hand surface cleaning apparatus of clause 1 wherein the pre-motor filter has a hollow interior which is downstream of the pleated filter material, the hollow interior has an outlet end and an inlet end of the suction motor faces the outlet end of the hollow interior. 
         5. The hand surface cleaning apparatus of clause 1 wherein the rigid porous member comprises a screen. 
         6. The hand surface cleaning apparatus of clause 1 wherein the screen is conical or frustoconical in shape. 
         7. A hand surface cleaning apparatus having a front end and a rear end, the hand surface cleaning apparatus comprising:
       (a) an air flow path from a dirty air inlet to a clean air outlet:   (b) an air treatment chamber provided in the air flow path, the air treatment chamber comprising a front end, a rear end, an air treatment chamber air inlet and an air treatment chamber air outlet, the air treatment chamber air outlet comprising a porous member:   (c) a pre-motor filter that is at least partially nested in the porous member; and,   (d) a motor and fan assembly provided in the air flow path.   
     
         8. The hand surface cleaning apparatus of clause 7 wherein the air treatment chamber comprises a cyclone having a cyclone axis of rotation wherein the cyclone axis of rotation extends through the front and rear ends of the hand vacuum cleaner. 
         9. The hand surface cleaning apparatus of clause 7 wherein the pre-motorfilter comprises a pleated filter material. 
         10. The hand surface cleaning apparatus of clause 9 wherein the pleats extend in a forward/rearward direction. 
         11. The hand surface cleaning apparatus of clause 7 wherein the pre-motor filter has a hollow interior, the hollow interior has an outlet end and an inlet end of the suction motor faces the outlet end of the hollow interior. 
         12. The hand surface cleaning apparatus of clause 7 wherein the porous member is rigid. 
         13. The hand surface cleaning apparatus of clause 7 wherein the porous member comprises a screen. 
         14. The hand surface cleaning apparatus of clause 13 wherein the screen is conical or frustoconical in shape.