Patent Publication Number: US-9427122-B2

Title: Surface cleaning apparatus

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application claims benefit under 35 USC 120 as continuation in part of co-pending U.S. patent application Ser. No. 13/781,441, filed on Feb. 28, 2013, and co-pending U.S. patent application Ser. No. 13/541,745, filed on Jul. 4, 2012, which is a divisional application of co-pending U.S. patent application Ser. No. 12/720,570, filed on Mar. 9, 2010, which itself claims the benefit of priority under 35 USC 119 from Canadian Patent Application No. 2,658,402, filed on Mar. 13, 2009, Canadian Patent Application No. 2,674,056, filed on Jul. 28, 2009 and Canadian Patent Application No. 2,678,220 filed Sep. 8, 2009, entitled SURFACE CLEANING APPARATUS, the specifications of each of which are incorporated herein by reference in their entirety. 
    
    
     FIELD 
     This specification relates to a surface cleaning apparatus. In one embodiment, the surface cleaning apparatus has an above floor cleaning wand, which preferably comprises, consists essentially of or consists of the handle assembly, wherein the above floor cleaning wand is removable for above floor cleaning by using a wand release actuator which is provided on the above floor cleaning wand and is removable with the above floor cleaning wand. In some embodiments, the surface cleaning apparatus is an upright surface cleaning apparatus which also comprises a portable surface cleaning unit, such as a hand vacuum cleaner or a pod, which is selectively detachable from the upper portion. The above floor cleaning wand may be removable by itself and/or with the portable surface cleaning unit. 
     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. Typically, an upright vacuum cleaner includes an upper portion or upper section, including an air treatment member such as one or more cyclones and/or filters, drivingly mounted to a surface cleaning head. An up flow conduit is typically provided between the surface cleaning head and the upper portion. In some such vacuum cleaners, a spine, casing or backbone extends between the surface cleaning head and the upper portion for supporting the air treatment member. The suction motor may be provided in the upper portion or in the surface cleaning head. 
     Surface cleaning apparatus having a portable cleaning module that is removably mounted to an upright vacuum cleaner are known. See for example U.S. Pat. Nos. 5,309,600, 4,635,315 and US 2011/0314629. US 2011/0314629 discloses an upright vacuum cleaner having a surface cleaning head and an upright section pivotally mounted thereto. A hand vacuum cleaner or a pod is removably mounted on the upper portion and is connected in airflow communication with the surface cleaning head via a flexible hose. A portion of the upper portion is bendable so as to allow the surface cleaning head to extend under furniture. This bendable portion is external to the airflow path. In use, the hand vacuum cleaner is locked on the upper portion. A user may manually unlock the hand vacuum cleaner so as to remove it for use as a hand vacuum cleaner and/or for emptying the cyclone bin assembly. In addition, an above floor cleaning wand may be provided and may be removable with the pod. 
     SUMMARY 
     This summary is intended to introduce the reader to the more detailed description that follows and not 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 a first aspect there is provided a surface cleaning apparatus wherein the wand is removable from the upper portion with the wand release actuator and, optionally the wand lock mechanism comprising the locking member, is removable with the wand. The wand may be removable mounted in the upper portion. An advantage of this design is that the upper portion on or in which the wand may be mounted may have a lower vertical extent, thereby simplifying the process for a user to reinsert the wand. For example, the user may have a lower target for aligning and installing the wand providing a better vantage to view the required action and permitting the user to handle the wand at a more comfortable height during the installation operation. 
     In accordance with this aspect, there is provided a surface cleaning apparatus comprising a surface cleaning head having a dirty air inlet, an upper portion moveably mounted to the surface cleaning head between a storage position and a floor cleaning position, a portable surface cleaning unit comprising a suction motor and an air treatment member removably mounted to the upper portion, an above floor cleaning wand removably mounted to the upper portion, a flexible air flow conduit forming at least part of an air flow path from the above floor cleaning wand to the surface cleaning unit, and a wand lock having a locked position in which the wand is secured to the upper portion and an unlocked position in which the wand is removable from the upper portion. The wand lock may include a wand release actuator which is provided on the wand and is removable with the wand from the upper portion. 
     In some embodiments, the wand lock may further include a locking member that is releasably engageable with the upper portion. 
     The surface cleaning apparatus may further include a longitudinally extending transmission member that drivingly connects the wand release actuator to the locking member. The transmission member may be translatable downwardly when the wand lock is moved to the unlocked position. 
     In some embodiments, the locking member may be translated laterally to a position in which it is disengaged from the upper portion when the transmission member is translated downwardly. 
     In some embodiments, the portable surface cleaning unit may be removably mounted on an outer surface of the upper portion. 
     In some embodiments, the portable surface cleaning unit and the above floor cleaning wand may each be individually removable from the upper portion. 
     In some embodiments, the portable surface cleaning unit and the above floor cleaning wand may each be individually removable from the upper portion. 
     The surface cleaning apparatus may further include a portable surface cleaning unit lock having a locked position in which the portable surface cleaning unit is secured to the upper portion and an unlocked position in which the portable surface cleaning unit is removable from the upper portion. The portable surface cleaning unit lock may include a portable surface cleaning unit release actuator which is provided on the portable surface cleaning unit and is removable with the portable surface cleaning unit from the upper portion. 
     In some embodiments, the portable surface cleaning unit may be removably mounted on an outer surface of the upper portion. 
     In some embodiments, the portable surface cleaning unit may also be removably mounted to the wand. 
     In some embodiments, the portable surface cleaning unit may be slidably receivable on upper mounting members that are provided on the wand. 
     In some embodiments, the wand may be removably received in the upper portion. 
     In some embodiments, the upper portion may be in air flow communication with the dirty air inlet and. When the wand is positioned in the upper portion, the wand may be in air flow communication with the dirty air inlet and part of the upper portion may extend around the wand. 
     The surface cleaning apparatus may further include an air flow passage from the dirty air inlet to the upper portion. An air inlet end of the wand may be aligned with an outlet end of the air flow passage when the wand is received in the upper portion. 
     In some embodiments, the wand may include a lower end that is received in the upper portion and an upper end. The lower end may include a wand air inlet and the upper end may include a wand air outlet. A handle may be provided proximate the upper end of the wand, whereby, when the wand is received in the upper portion, the wand may be drivingly connected to the surface cleaning head and the upper portion may be configured to stabilize the wand when the wand is drivingly connected to the surface cleaning head. 
     In some embodiments, the upper portion may be configured as an alignment member and the wand may be receivable in the upper portion in a particular alignment. 
     In some embodiments, the upper portion may be generally egg shaped in transverse section and a portion of an outer surface of the wand may be generally egg shaped in transverse section. 
     In some embodiments, the upper portion may extend upwardly to surround a sufficient portion of the wand when the wand is positioned in the upper portion whereby the wand will remain in the upper portion when the wand lock is in the unlocked position. 
     In a second aspect there is provided a surface cleaning apparatus wherein a portable surface cleaning unit, such as a pod or a hand vac is removable from the upper portion. The portable surface cleaning unit is mounted to the outer surface and the mounting means provides support to the portable surface cleaning unit when the portable cleaning unit is in a removable configuration (e.g., the portable cleaning unit release lock is released). Upper and lower mounting members are provided and one or both may be configured to inhibit both lateral movement and forward rotation of the surface cleaning unit. Accordingly the surface cleaning apparatus may be used as an upright vacuum cleaner in a floor cleaning mode with the portable surface cleaning unit mounted to the upper portion and the portable cleaning unit stably mounted in position as the handle is used to drive and, preferably, steer, the surface cleaning head. For example, upper portion may be provided with two laterally extending wings. The surface cleaning unit may have arms that surround the upper portion and have recesses for receiving the wings. The wings may have a sufficient height to prevent both lateral movement and forward rotation of the surface cleaning unit. This enables the portable unit to remain in position while the portable unit is in an unlocked mode. A second set of upper arms may be provided, e.g., on a removable wan to assist or prevent the surface cleaning unit rotating forward when the surface cleaning unit is unlocked. 
     In accordance with this aspect, there is provided a surface cleaning apparatus comprising a surface cleaning head having a dirty air inlet, an upper portion moveably mounted to the surface cleaning head between a storage position and a floor cleaning position, an above floor cleaning wand removably receivable in the upper portion and having a longitudinally extending axis, a flexible air flow conduit forming at least part of an air flow path from the above floor cleaning wand to the portable surface cleaning unit, a lower mounting member provided on an outer surface of the upper portion, an upper mounting member provided on at least one of the outer surface of the upper portion and the wand, and a portable surface cleaning unit comprising a suction motor and an air treatment member removably mounted to the upper portion. 
     In some embodiments, at least one of the upper and lower mounting members may inhibit rotational movement of the portable surface cleaning unit around the axis of the wand. 
     In some embodiments, the portable surface cleaning unit may be slidably mountable with respect to the upper and lower mounting members. 
     In some embodiments, the portable surface cleaning unit may be vertically removable from the upper and lower mounting members. 
     In some embodiments, the surface cleaning apparatus may further include a steering coupling wherein the upper portion may be steeringly coupled to the surface cleaning head. 
     In some embodiments, the lower mounting member may include a pair of lower wings extending laterally outwardly from the upper portion. The portable surface cleaning unit may have mating recesses provided on a lower surface thereof. 
     In some embodiments, the surface cleaning apparatus may further include a wand lock having a locked position in which the wand is secured to the upper portion and an unlocked position in which the wand is removable from the upper portion. The upper mounting member may be provided on the wand. 
     In some embodiments, the wand lock may be operable to remain in the unlocked position once moved to the unlocked position. The upper mounting member may include a pair of upper wings extending laterally outwardly from the wand. The portable surface cleaning unit may include a pair of arms that at least partially surround the upper wings, whereby the wand remains in position when the wand lock is moved to the unlocked position. 
     In some embodiments, the wand lock may be operable to remain in the unlocked position once moved to the unlocked position and the upper mounting member may include a pair of wings extending laterally outwardly from the wand. Each wing may have a first surface that faces towards the portable surface cleaning unit, and an opposed face. The portable surface cleaning unit may include a pair of arms wherein each arm contacts a portion of the opposed face of one of the wings, whereby the wand remains in position when the wand lock is moved to the unlocked position. 
     In accordance with this aspect, there is also provided another surface cleaning apparatus comprising a surface cleaning head having a dirty air inlet, an upper portion moveably mounted to the surface cleaning head between a storage position and a floor cleaning position, an above floor cleaning wand removably mounted to the upper portion, a flexible air flow conduit forming at least part of an air flow path from the above floor cleaning wand to the portable surface cleaning unit, a lower mounting member provided on an outer surface of the upper portion, an upper mounting member provided on at least one of the outer surface of the upper portion and the wand, a portable surface cleaning unit comprising a suction motor, and an air treatment member removably mounted on an outer surface of the upper portion. The portable surface cleaning unit may be slidably mountable with respect to the upper and lower mounting members. 
     In some embodiments, at least one of the upper and lower mounting members may inhibit rotational movement of the portable surface cleaning unit around a longitudinally extending axis of the wand. 
     In some embodiments, the portable surface cleaning unit may be vertically removable from the upper and lower mounting members. 
     In some embodiments, the surface cleaning apparatus may further include a steering coupling wherein the upper portion is steeringly coupled to the surface cleaning head. 
     In some embodiments, the lower mounting member may include a pair of lower wings extending laterally outwardly from the upper portion. The portable surface cleaning unit may have mating recesses provided on a lower surface thereof. 
     In some embodiments, the surface cleaning apparatus may further include a wand lock having a locked position in which the wand is secured to the upper portion and an unlocked position in which the wand is removable from the upper portion. The upper mounting member may be provided on the wand. 
     In some embodiments, the wand lock may be operable to remain in the unlocked position once moved to the unlocked position. The upper mounting member may include a pair of upper wings extending laterally outwardly from the wand. The portable surface cleaning unit may include a pair of arms that at least partially surround the upper wings, whereby the wand remains in position when the wand lock is moved to the unlocked position. 
     In some embodiments, the wand lock may be operable to remain in the unlocked position once moved to the unlocked position and the upper mounting member may include a pair of wings extending laterally outwardly from the wand. Each wing may have a first surface that faces towards the portable surface cleaning unit and an opposed face. The portable surface cleaning unit may include a pair of arms wherein each arm contacts a portion of the opposed face of one of the wings, whereby the wand remains in position when the wand lock is moved to the unlocked position. 
     In a third aspect there is provided a surface cleaning apparatus having an upper portion wherein an above floor cleaning wand is removably receivable in the upper portion and the upper portion and wand are configured to permit the wand to be driving connected to the surface cleaning head when the wand is installed in the upper portion. A portable surface cleaning unit may be removably mounted, e.g., to an outer surface of the upper portion. 
     For example, the upper portion may surround the up flow duct from the surface cleaning head and may be non-circular, e.g., egg shaped, and the inlet end of the wand may have a mating shape. Accordingly, the wand may be dynamically stably mounted when inserted into the upper portion. For example, the upper portion provides lateral support for the wand when the wand is inserted into the upper portion. This supports the mechanical stresses imposed when the wand is used to steer the surface cleaning head. In addition a keyed slot may also be provided in the upper housing to assist in aligning the wand during insertion. 
     In accordance with this aspect, there is provided a surface cleaning apparatus comprising a surface cleaning head having a dirty air inlet, an upper portion moveably mounted to the surface cleaning head between a storage position and a floor cleaning position, a portable surface cleaning unit comprising a suction motor and an air treatment member removably mounted to the upper portion, an above floor cleaning wand removably receivable in the upper portion, a wand lock having a locked position in which the wand is secured to the upper portion and an unlocked position in which the wand is removable from the upper portion, and a flexible air flow conduit forming at least part of an air flow path from the above floor cleaning wand to the surface cleaning unit. The wand may include a lower end and an upper end. The lower end may be received in the upper portion and include a wand air inlet. The upper end may include a wand air outlet. A handle may be provided proximate the upper end of the wand, whereby, when the wand is received in the upper portion, the wand may be drivingly connected to the surface cleaning head. The upper portion may be configured to stabilize the wand when the wand is drivingly connected to the surface cleaning head. 
     In some embodiments, the upper portion may be in air flow communication with the dirty air inlet and, when the wand is positioned in the upper portion, the wand may be in air flow communication with the dirty air inlet and part of the upper portion may extend around the wand. 
     In some embodiments, the surface cleaning apparatus may further include an air flow passage from the dirty air inlet to the upper portion and an air inlet end of the wand may be aligned with an outlet end of the air flow passage when the wand is received in the upper portion. 
     In some embodiments, the upper portion may be configured as an alignment member and the wand may be receivable in the upper portion in a particular alignment. 
     In some embodiments, the upper portion may be generally egg shaped in transverse section and a portion of an outer surface of the wand may be generally egg shaped in transverse section. 
     In some embodiments, the upper portion may extend upwardly to surround a sufficient portion of the wand when the wand is positioned in the upper portion whereby the wand will remain in the upper portion when the wand lock is in the unlocked position. 
     In some embodiments, the portable surface cleaning unit may be removably mounted on an outer surface of the upper portion. 
     In some embodiments, the portable surface cleaning unit may also be removably mounted to the wand. 
     In some embodiments, the portable surface cleaning unit may be slidably receivable on upper mounting members that are provided on the wand. 
     In some embodiments, the upper portion may terminate below an upper end of the portable surface cleaning unit. 
     In some embodiments, the flexible air flow conduit may include an electrified flexible air flow conduit having a wand electrical engagement member. The upper portion may have an interior in which the wand may be received. The interior may include a cleaning head electrical engagement member and the electrical engagement members may be electrically connected when the electrified flexible air flow conduit is received in the upper portion whereby the electrified flexible air flow conduit is electrically connected to the surface cleaning head. 
     In some embodiments, the surface cleaning apparatus may further include an air flow passage from the dirty air inlet to the upper portion and an air inlet end of the wand may be aligned with an outlet end of the air flow passage when the wand is received in the upper portion. 
     In some embodiments, the outlet end of the air flow passage and the cleaning head electrical engagement member may be positioned at a lower end of the interior. 
     In accordance with this aspect, there is also provided surface cleaning apparatus comprising a surface cleaning head having a dirty air inlet and an electrically operated component, an upper portion moveably mounted to the surface cleaning head between a storage position and a floor cleaning position, the upper portion having an interior, an air flow passage extends from the dirty air inlet to the upper portion and an outlet of the air flow passage is located in the interior, a portable surface cleaning unit comprising a suction motor and an air treatment member removably mounted to the upper portion, an above floor cleaning wand removably receivable in the upper portion, the wand comprising a lower end having an air inlet and an upper end having an air outlet, a wand lock having a locked position in which the wand is secured to the upper portion and an unlocked position in which the wand is removable from the upper portion, and an electrified flexible air flow conduit forming at least part of an air flow path from the above floor cleaning wand to the surface cleaning unit and electrically connecting the surface cleaning head to the surface cleaning unit at a location on in the interior when the wand is received in the upper portion. 
     In some embodiments, the upper portion may be configured as a first alignment member, and the wand may be receivable in the upper portion in a particular alignment. 
     In some embodiments, the surface cleaning apparatus may further include a cleaning head electrical engagement member located in the interior that is electrically connectable with a wand electrical engagement member provided on the wand when the wand is received in the upper portion. A second alignment member may be associated with the cleaning head electrical engagement member. 
     In some embodiments, the upper portion may be generally egg shaped in transverse section and a portion of an outer surface of the wand may be generally egg shaped in transverse section. 
     In some embodiments, the upper portion may extend upwardly to surround a sufficient portion of the wand when the wand is positioned in the upper portion whereby the wand will remain in the upper portion when the wand lock is in the unlocked position. 
     In accordance with this aspect, there is also provided a surface cleaning apparatus comprising a surface cleaning head having a dirty air inlet, an upper portion moveably mounted to the surface cleaning head between a storage position and a floor cleaning position, a portable surface cleaning unit comprising a suction motor and an air treatment member removably mounted to the upper portion, an above floor cleaning wand removably receivable in the upper portion, a wand lock having a locked position in which the wand is secured to the upper portion and an unlocked position in which the wand is removable from the upper portion, and a flexible air flow conduit forming at least part of an air flow path from the above floor cleaning wand to the surface cleaning unit. The upper portion may extend upwardly to surround a sufficient portion of the wand when the wand is positioned in the upper portion whereby the wand will remain in the upper portion when the wand lock is in the unlocked position. 
     In some embodiments, the upper portion may be configured as a first alignment member, and the wand may be receivable in the upper portion in a particular alignment. 
     In some embodiments, the flexible air flow conduit is electrified and the surface cleaning apparatus further comprises a power tool that is powered by a circuit that includes the flexible electrified air flow conduit. 
     In some embodiments, the surface cleaning head is adapted to removable receive a hard floor cleaning member. 
     In some embodiments, the upper portion is steeringly coupled to the surface cleaning head. 
     It will be appreciated by a person skilled in the art that a surface cleaning apparatus 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. 
     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. 
    
    
     
       DRAWINGS 
         FIG. 1  is a front perspective view of a surface cleaning apparatus in a storage position; 
         FIG. 2  is a rear perspective view of the surface cleaning apparatus of  FIG. 1 , in the storage position; 
         FIG. 3  is a front perspective view of the surface cleaning apparatus of  FIG. 1 , in a floor cleaning position; 
         FIG. 3 a    is a side elevation view of the surface cleaning apparatus of  FIG. 1 , in a storage position; 
         FIG. 4  is a partial cross-sectional view taken along line  4 - 4  in  FIG. 1 ; 
         FIG. 5  is a rear perspective view of the surface cleaning apparatus of  FIG. 1 , in a partially disassembled configuration; 
         FIG. 6  is a front perspective view of the surface cleaning apparatus of  FIG. 1 , with the pod removed but still in air flow communication with the surface cleaning head; 
         FIG. 7  is a front perspective view of the surface cleaning apparatus of  FIG. 1 , in an above-floor cleaning configuration; 
         FIG. 8  is a front perspective view of the surface cleaning apparatus of  FIG. 1  wherein the cyclone bin assembly has been removed; 
         FIG. 9  is a rear perspective view of the portable surface cleaning unit with the cyclone bin assembly removed; 
         FIG. 10  is a front perspective view of a cyclone bin assembly with the lid in an open position; 
         FIG. 11  is a rear perspective view of the above floor cleaning wand disconnected from an upper portion for use in above floor cleaning, the remaining parts have been removed for clarity; 
         FIG. 12  is a top plan view of the upper portion and the surface cleaning head of  FIG. 11 ; 
         FIG. 13  is a top plan view of the surface cleaning apparatus of  FIG. 1 , with the above floor cleaning wand removed from the upper portion; 
         FIG. 14  is a rear perspective view of the above floor cleaning wand partially removed from the upper portion; 
         FIG. 15  is a rear perspective view of the portable surface cleaning unit; 
         FIG. 16  is a bottom plan view of the surface cleaning unit of  FIG. 15 ; 
         FIG. 17  is a front elevation view of the upper portion and the surface cleaning head of  FIG. 11 ; 
         FIG. 18  is a cross-sectional view taken alone line  18 - 18  in  FIG. 11 ; 
         FIG. 19  is a cross-sectional view taken alone line  19 - 19  in  FIG. 4 ; 
         FIG. 20  is a rear elevation view of the surface cleaning unit of  FIG. 15 ; 
         FIGS. 21 a -21 d    are rear perspective views of the surface cleaning unit of  FIG. 15  with a rear wall removed and the locking mechanism in different positions; 
         FIG. 22  is a partial rear sectional perspective view of the wand of  FIG. 11 ; 
         FIGS. 23 a -23 d    are partial rear perspective views of the wand of  FIG. 11  with an outer wall removed. 
         FIG. 24  is a front perspective view of an alternate example of a upright surface cleaning apparatus with a removable surface cleaning unit mounted thereto; 
         FIG. 25  is a side elevation view of the surface cleaning apparatus of  FIG. 24 ; 
         FIG. 26  is a side elevation view of the surface cleaning apparatus of  FIG. 24  with the cleaning unit removed from the upper portion; 
         FIG. 27  is a side elevation view of the surface cleaning apparatus of  FIG. 24  with the cleaning unit separated from the flexible hose; 
         FIG. 27 a    is a front perspective view of a mounting member for the portable surface cleaning unit of  FIGS. 24-27 ; 
         FIG. 28  is a front perspective view of a further alternate example of a upright surface cleaning apparatus with a removable surface cleaning unit mounted thereto; 
         FIG. 28 a    is a front perspective view of an auxiliary cleaning tool that may be connected to the inlet end of the above floor cleaning wand; 
         FIG. 28 b    is a front perspective view of a power tool that may be connected to the inlet end of the above floor cleaning wand; 
         FIG. 29  is a front perspective view for the surface cleaning apparatus of  FIG. 1  with the surface cleaning unit and the hose removed; 
         FIG. 30  is a partial cross-sectional view in perspective taken along line  4 - 4  in  FIG. 1 ; 
         FIGS. 31-33  are front perspective view of the surface cleaning unit being mounted on the upper portion; 
         FIG. 34  is a front perspective view of an alternate floor cleaning tool which includes a suction inlet and a hard floor cleaning cloth; 
         FIG. 35  is a bottom plan view of the alternate floor cleaning tool of  FIG. 34 ; 
         FIG. 36  is a front perspective view of the alternate floor cleaning tool of  FIG. 34  with the hard floor cleaning cloth removed; 
         FIG. 37  is a bottom perspective view of the alternate floor cleaning tool of  FIG. 34  with the hard floor cleaning cloth removed; and, 
         FIG. 38  is a perspective view of the cleaning surface of the hard floor cleaning cloth. 
     
    
    
     DESCRIPTION OF VARIOUS EMBODIMENTS 
     Various apparatuses or processes will be 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 processes or apparatuses that differ from those described below. The claimed inventions are not limited to apparatuses or processes having all of the features of any one apparatus or process described below or to features common to multiple or all of the apparatuses described below. It is possible that an apparatus or process described below is not an embodiment of any claimed invention. Any invention disclosed in an apparatus or process 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 applicants, inventors or owners do not intend to abandon, disclaim or dedicate to the public any such invention by its disclosure in this document. 
     General Description of an Upright Vacuum Cleaner 
     Referring to  FIGS. 1-3 , a first embodiment of a surface cleaning apparatus  100  is shown. In the embodiment shown, the surface cleaning apparatus  100  is an upright vacuum cleaner. In alternate embodiments, the surface cleaning apparatus may be another suitable type of surface cleaning apparatus, such as a stick vac, a wet-dry type vacuum cleaner or a carpet extractor. 
     In the illustrated example, the surface cleaning apparatus  100  includes an upper portion or support structure  104  that is movably and drivingly connected to a surface cleaning head  108 . A surface cleaning unit  112  is mounted on the upper portion  104 . The surface cleaning apparatus  100  also has at least one dirty air inlet  116 , at least one clean air outlet  120 , and an air flow path or passage extending therebetween. In the illustrated example, the air flow path includes at least one flexible air flow conduit member (such as a hose  124  or other flexible conduit). Alternatively, the air flow path may be formed from rigid members. 
     At least one suction motor and at least one air treatment member are positioned in the air flow path to separate dirt and other debris from the airflow. The suction motor and the air treatment member may be provided in the upper portion and/or the surface cleaning head of an upright surface cleaning apparatus. Preferably, the suction motor and the air treatment member are provided in a removable surface cleaning unit. The air treatment member may be any suitable air treatment member, including, for example, one or more cyclones, filters, and bags, and preferably the at least one air treatment member is provided upstream from the suction motor. Preferably, as exemplified in  FIG. 4 , the portable surface cleaning unit  112  includes both the suction motor  128 , which may be in a motor housing  132 , and an air treatment member, which may be in the form of a cyclone bin assembly  136 . Accordingly, surface cleaning unit  112  may be a hand vacuum cleaner, a pod or the like. The motor housing  132  can include at least one removable or openable door  140  which may allow a user to access the interior of the motor housing  132 , for example to access the motor  128 , a filter or any other component within the housing  132 . The cyclone bin assembly  136  includes a cyclone chamber  144  and a dirt collection chamber  148 . 
     In the embodiment shown, the surface cleaning head  108  includes the dirty air inlet  116  in the form of a slot or opening  152  ( FIG. 4 ) formed in a generally downward facing surface of the surface cleaning head  108 . From the dirty air inlet  116 , the air flow path extends through the surface cleaning head  108 , and through an up flow conduit  156  ( FIG. 2 ) in the upper portion  104  to the surface cleaning unit  112 . In the illustrated example, the clean air outlet  120  is provided in the front of the surface cleaning unit  112 , and is configured to direct the clear air in a generally lateral direction, toward the front of the apparatus  100 . 
     A handle  160  is provided on the upper portion  104  to allow a user to manipulate the surface cleaning apparatus  100 . Referring to  FIGS. 2, 3, and 3   a , the upper portion extends along an upper axis  164  and is moveably mounted to the surface cleaning head  108 . In the illustrated example, the upper portion  104  is pivotally mounted to the surface cleaning head via a pivot joint  168 . The pivot joint  168  may be any suitable pivot joint. In this embodiment, the upper portion  104  is movable, relative to the surface cleaning head  108 , between a storage position ( FIG. 1 ), and a use or floor cleaning position ( FIG. 3 ). In the floor cleaning position, the upper portion  104  may be inclined relative to the surface being cleaned, and an angle  172  between a plane  176  parallel to the surface and the upper axis  164  may be between about 20° and about 85°. In the storage position ( FIG. 3 a   ), the upper portion  104  may be inclined relative to the surface being cleaned, and the angle  172  between the plane  176  parallel to the surface and the upper axis  164  may be between about 85° and 135°. 
     Alternatively, or in addition to being pivotally coupled to the surface cleaning head  108 , the upper portion  104  may also be rotatably mounted to surface cleaning head  108 . In this configuration, the upper portion  104 , and the surface cleaning unit  112  supported thereon, may be rotatable about the upper axis  164 . In this configuration, rotation of the upper portion  104  about the upper axis  164  may help steer the surface cleaning head  108  across the floor (or other surface being cleaned). Alternately, the upper portion  104  may be pivotally mounted to the surface cleaning head about a second pivot axis, or otherwise moveable mounted with respect to the surface cleaning head, to provide steering. 
     It will be appreciated that the forgoing discussion is exemplary and that an upright vacuum cleaner may use a surface cleaning head and upper portion of any design and they may be moveably connected together by any means known in the art. 
     Cleaning Modes 
     The following is a description of the components of the surface cleaning apparatus that are configured to be disconnectable that may be used by itself in any surface cleaning apparatus or in any combination or sub-combination with any other feature or features disclosed herein. 
     Accordingly, in one aspect, the upright vacuum cleaner  100  may be operable in a variety of different functional configurations or operating modes. The versatility of operating in different operating modes may be achieved by permitting the surface cleaning unit  112  to be detachable, e.g., from the upper portion  104 . Alternatively, or in addition, further versatility may be achieved by permitting portions of the vacuum cleaner (e.g., one or more of a surface cleaning head, an above floor cleaning wand, a handle assembly, a hose) to be detachable from each other at a plurality of locations, and re-connectable to each other in a variety of combinations and configurations. 
     In the examples illustrated, mounting the surface cleaning unit  112  on the upper portion  104  increases the weight of the upper portion  104  and can affect the maneuverability and ease of use of the surface cleaning apparatus  100 . With the surface cleaning unit  112  attached, the vacuum cleaner  100  may be operated like a traditional upright style vacuum cleaner, as illustrated in  FIGS. 1-3 and 25 . 
     Alternatively, in some cleaning situations the user may preferably detach the surface cleaning unit  112  from the upper portion  104  and choose to carry the surface cleaning unit  112  (e.g. by hand or by a strap) separately from the upper portion  104 , while still using the upper portion  104  to drivingly maneuver the surface cleaning head  108 . When the surface cleaning unit  112  is detached, a user may more easily maneuver the surface cleaning head  108  around or under obstacles, like furniture and stairs (e.g.,  FIG. 28 ). 
     To enable the vacuum suction generated by the surface cleaning unit  112  to remain in airflow communication with the surface cleaning head  108  when the surface cleaning unit  112  is detached from the support structure  104 , the airflow connection between the surface cleaning head  108  and the cleaning unit  112  is preferably at least partially formed by a flexible conduit, such as flexible hose  124 , which may be an electrified hose. Preferably, the hose  124  is extensible and more preferably is elastically or resiliently extensible. The use of a flexible conduit allows a user to detach the surface cleaning unit  112  and maintain a flow connection between the portable surface cleaning unit  112  and the surface cleaning head  108  without having to reconfigure or reconnect any portions of the airflow conduit  184  ( FIG. 6 ). 
     In the example shown, the airflow path between the surface cleaning head  108  and the cleaning unit  112  further includes an above floor cleaning wand  180 . Wand  180  may be positioned upstream of hose  124  and downstream of surface cleaning head  108 . Preferably, wand  180  may be drivingly connected to upper portion  104  so that wand  108  may be used to direct surface cleaning head  108  (e.g., forwardly and rearwardly) and, optionally, for also steering surface cleaning head  108 . Accordingly, wand  180  comprises a rigid airflow conduit having any suitable shape. For example, wand  180  may be straight as shown or it may be curved or bent. In some embodiments, wand  180  may be reconfigurable. For example, wand  108  may have upper and lower sections that are moveably mounted with respect to each other (e.g., pivotally connected) so that wand  180  may be converted from a straight configuration to a bent configuration. Further, wand  180  may have any suitable cross-sectional shape, such as a circular cross-section as shown, or another cross-sectional shape such as square, triangular, or another regular or irregular shape. 
     Wand  180  may be telescopic so that it is extendable. 
     In order to enable a user to use wand  180  to remotely maneuver surface cleaning head  108 , wand  180  may be provided with a handle assembly. Preferably, handle assembly or handle  160  is positioned proximate an upper (i.e. downstream) end  188  of wand  180 . For example, handle  160  may be connected to one or both of wand  180  and hose  124 . Optionally, handle  160  may form part of the airflow path between wand  180  and hose  124 . Alternatively, handle  160  may be peripherally attached to one or both of wand  180  and hose  124  without participating in the airflow communication between wand  180  and hose  124 . 
     A user may grasp a hand grip portion  182  of handle  160  to manipulate wand  180  (e.g. for moving upper portion  104  and steering surface cleaning head  108 ). In alternative embodiments, surface cleaning apparatus  100  may not include a handle  160  and instead a user may grasp wand  180  directly. 
     Reference is now made to  FIG. 5 . As shown, upper portion  104  is moveably mounted with respect to surface cleaning head  108 . Upper portion  104  may be connected to surface cleaning head  108  by any means known in the art, (e.g., it may be pivotally mounted, rotationally mounted or the like). As exemplified, pivot joint  168  permits upper portion  104  to tilt and/or pivot with respect to surface cleaning head  108 . 
     One or both of wand  180  and surface cleaning unit  112  may be selectively attached or detached from upper portion  104 . As exemplified, each of wand  180  and surface cleaning unit  112  is selectively attachable or detachable from upper portion  104 . An advantage of this design is that a user may convert the vacuum cleaner to a surface cleaning mode by removing the wand without having to remove surface cleaning unit  112 . Preferably, each of wand  180  and surface cleaning unit  112  may be selectively connected or disconnected from upper portion  104  independently of the other. For example, wand  180  and surface cleaning unit  112  may be connected or disconnected from upper portion  104  in any order, sequentially or simultaneously. This may simplify the reconfiguration of surface cleaning apparatus  100  into different cleaning modes without requiring disruption to the operation of surface cleaning apparatus  100 . 
     As exemplified, when upstream end  192  of wand  180  is connected to upper portion  104 , the surface cleaning head  108  participates in the airflow path in a floor cleaning mode, e.g., for cleaning floors, stairs, and the like. In such a case, the surface cleaning unit  112  may be mounted on upper portion  104 , for supporting the weight of surface cleaning unit on upper portion  104  (e.g., as shown in  FIGS. 3 and 25  which exemplifies a traditional floor cleaning mode for an upright vacuum cleaner). Alternately, surface cleaning unit  112  may be dismounted from upper portion  104  and carried by hand, worn as a backpack, or placed on the floor for example while wand  180  is connected to surface cleaning head  108  (e.g., as shown in  FIGS. 6 and 28  which exemplifies an alternate floor cleaning mode for an upright vacuum cleaner). 
     As exemplified, wand  180  may be disconnected from upper portion  104  for use in an above-floor cleaning mode. In one embodiment, surface cleaning unit  112  may be mounted on upper portion  104 , for supporting the weight of surface cleaning unit on upper portion  104  while wand  180  is used in the above floor cleaning mode (e.g., as shown in  FIGS. 7 and 24 ). Alternately, in another optional embodiment, surface cleaning unit  112  may also be dismounted from upper portion  104  and carried by hand, worn as a backpack, or placed on the floor for example while wand  180  is used in the above floor cleaning mode. 
     Wand  180  may be selectively connected or disconnected from the airflow path, such as when the extension in reach it provides is not required. For example, downstream end  188  of wand  180  may be separated from handle  160 . The reduced reach provided by this configuration may be advantageous where the user may wish to manipulate the cleaning surface by hand (e.g. separate cushions in a couch) while cleaning, or where the user may require fine control (e.g. to avoid sucking up objects on the cleaning surface). 
     If Wand  180  and surface cleaning unit  112  are each individually removable, then they may each be independently mounted to upper portion  104 . Wand  180  and surface cleaning unit  112  may connect to upper portion  104  in any suitable fashion. In the example shown, wand  180  is inserted into upper portion  104 , and surface cleaning unit  112  is mounted to an exterior of upper portion  104 . In such a case, upper portion  104  may provide part or all of the air flow path from surface cleaning head  108  to wand  180 . In other embodiments, upper portion  104  need not be part of the air flow path. For example, wand  180  may be mounted to the exterior of upper portion  104  and the inlet end may seat on an outlet end of a duct provided on the outer surface of the upper portion  104 . 
     Referring to  FIG. 6 , when the surface cleaning apparatus  100  is in use, a user may detach the surface cleaning unit  112  from the upper portion  104  without interrupting the airflow communication between the cleaning unit  112  and the surface cleaning head  108 . This allows a user to selectively detach and re-attach the cleaning unit  112  to the support structure  104  during use without having to stop and reconfigure the connecting hose  124  or other portions of the airflow conduit  184 . As exemplified, wand  180  is attached to upper portion  104  and surface cleaning unit  112  is detached from upper portion  104 . 
       FIG. 6  illustrates a configuration in which the vacuum cleaner  100  can be operated with the surface cleaning unit  112  detached from the upper portion  104  and the air flow path between the surface cleaning unit  112  and the surface cleaning head  108  remains intact. In this configuration, upper portion  104  may provide a connection between wand  180  and surface cleaning head  108 , which may permit surface cleaning head  108  to be driven by manipulating wand  180 . 
     In addition to being operable to clean floors or surfaces, the vacuum cleaner may be operated in a variety of cleaning modes that do not include use of the surface cleaning head, and may be generally described as above floor cleaning modes. This can generally include cleaning furniture, walls, drapes and other objects as opposed to cleaning a large, planar surface. 
     In one example of an above floor cleaning mode, as exemplified in  FIG. 7 , the surface cleaning unit  112  can remain mounted on the upper portion  104 . This eliminates the need for the user to separately support the weight of the surface cleaning unit  112  in an above floor cleaning mode. In the illustrated configuration, the surface cleaning unit  112  may remain mounted on the upper portion  104  and the wand  180  may be detached from upper portion  104  to provide an extended reach for above floor cleaning. Optionally, additional accessory tools may be coupled to the upstream end  192  of wand  180 , including for example a crevice tool, a cleaning brush (optionally an electrically powered brush or an air driven turbo brush) and any other type of accessory including a power tool such as a sander. 
     Further, as illustrated in  FIG. 5 , the upstream end  200  of the handle  160  may be separated from the downstream end  188  of wand  180 . In this configuration the upstream end  200  of the handle  160  can function as the dirty air inlet for the vacuum cleaner  100 . Optionally, accessory tools, such as wands, crevasse tools, turbo brushes, hoses or other devices may be coupled to the upstream end  200  of the handle  160 . 
     In another example of an above floor cleaning mode, as exemplified in  FIG. 5 , the surface cleaning unit  112  and wand  180  can both be detached from the upper portion  104 . The upstream end  200  of handle  160  may be selectively connected or disconnected from downstream end  188  of wand  180  as desired. This configuration may be advantageous when surface cleaning unit  112  must be held above the floor (e.g. while the user is standing on a ladder). In this case, the upper portion  104  and surface cleaning head  108  may add unnecessary weight to the surface cleaning unit  112 . This configuration may also be advantageous when the surface cleaning unit  112  is to be rested on a sloped surface. In this case, the rear wheels  204  and the front wheels or glides (not shown) of surface cleaning head  108  may allow surface cleaning unit  112  to roll away. By detaching surface cleaning unit  112  from surface cleaning head  108 , surface cleaning unit  112  may be placed directly on the sloped surface. Optionally, additional accessory tools may be coupled to the upstream end  192  of the wand  180 . 
     Optionally, one or more auxiliary support members, including for example a wheel and a roller, can be provided on the rear of the surface cleaning apparatus and/or the upper portion and configured to contact the floor (or other surface) when the upper portion is inclined or placed close to the surface. Providing an auxiliary support member may help carry some of the weight of the surface cleaning unit and/or upper portion when in a generally horizontal configuration. The auxiliary support member may also help the upper portion  104  and/or surface cleaning unit  112  to roll relatively easily over the floor when in a generally horizontal position. This may help a user to more easily maneuver the upper portion and/or surface cleaning unit under obstacles, such as a bed, cabinet or other piece of furniture. 
     Reference is now made to  FIGS. 24-27 , in which like part numbers refer to like parts in the other figures, where a surface cleaning apparatus  1500  is shown in accordance with another embodiment. As shown, surface cleaning apparatus  1500  includes an upper portion  104  connected by a joint  168  to a surface cleaning head  108  having a dirty air inlet  116 . A downstream end  1010  of upper portion  104  may define an opening  1014  for an air outlet  1074 . A wand  180  ( FIG. 24 ) is shown including an upstream end  192 , and a downstream end  188  in air flow communication with a hose  124 . Hose  124  is shown in air flow communication with a surface cleaning unit  112  having a cyclone bin assembly  136 , a motor housing  132 , and a clean air outlet  120 . 
       FIG. 27 a    shows an enlargement of mounting apparatus  1174  of upper portion  104 . As shown, mounting apparatus  1174  includes first and second wings  1508   a  and  1508   b . Wings  1508   a  and  1508   b  may be sized and positioned to be removably receivable in recesses of mounting member  1502 . In some examples, mounting apparatus  1174  may also provide a conduit  1510  for connecting surface cleaning unit  112  in air flow communication with hose  124 . As shown, conduit  1510  includes an air inlet  1512  that may be connected, and optionally removably connected, to a downstream end of hose  124 , and an air outlet  1514  that may be connected to surface cleaning unit  112  (e.g. when surface cleaning unit is mounted to mounted apparatus  1174 ). 
     In  FIG. 24 , an air flow pathway extends from upstream end  192  of wand  180  through wand  180  to downstream end  188  of wand  180 , through hose  124  into surface cleaning unit  112  through cyclone bin assembly  136  and motor housing  132 , and then to outlet  120 . In some examples, wand  180  may be shaped so that it can be received within or in air flow communication with upper opening  1014  of upper portion  104 . In these examples, when wand  180  is not in use it can be received within, and thereby stored within the upper portion  104  or mounted to downstream end  1014  of upper portion  104  (see for example  FIGS. 25-27 ). For example, upstream portion  1002  of wand  180  may be received in downstream portion  1006  of upper portion  104  such that outer walls  1022  of upstream portion  1022  and inner walls  1018  of downstream portion  1016  are in facing relationship. The air flow pathway may then extend from dirty air inlet  116  through surface cleaning head  108  to upper portion  104 , through air outlet  1074  into wand  180  and downstream to clean air outlet  120  as described above. 
     As shown, the apparatus  1500  may further include a handle  160  having a hand grip portion  182 . Handle  160  may be drivingly connected to surface cleaning head  108 , such as by way of upper portion  104  and joint  168  for steering apparatus  1500 . In some examples, wand  180  may be connected to handle  160 , such as shown in  FIG. 28 . For example, upstream end  200  of handle  160  may be connected to downstream end  188  of wand  180 . 
     Removable Cyclone 
     The following is a description of a removable cyclone that may be used by itself in any surface cleaning apparatus or in any combination or sub-combination with any other feature or features disclosed herein. 
     Reference is now made to  FIGS. 8 and 9 . Optionally, the cyclone bin assembly  136  may be detachable from the motor housing  132 . Providing a detachable cyclone bin assembly  136  may allow a user to carry the cyclone bin assembly  136  to a garbage can for emptying, without needing to carry or move the rest of the surface cleaning apparatus  100  or the surface cleaning unit  112 . Preferably, the cyclone bin assembly  136  can be separated from the motor housing  132  while the surface cleaning unit  112  is mounted on the upper portion  104  and also when the surface cleaning unit  112  is separated from the upper portion  104 .  FIG. 8  illustrates an embodiment where the cyclone bin assembly  136  is removable as a closed module, which may help prevent dirt and debris from spilling out of the cyclone bin assembly  136  during transport. 
     Optionally, as exemplified, removing the cyclone bin assembly  136  reveals a pre-motor filter chamber  208  that is positioned in the air flow path between the cyclone bin assembly  136  and the suction motor  128 . One or more filters may be provided in the pre-motor filter chamber  208  to filter the air exiting the cyclone bin assembly  136  before it reaches the motor  128 . In the illustrated example, the pre-motor filter includes at least a foam filter  212  positioned within the pre-motor filter chamber  208 . Preferably, filter  212  is removable to allow a user to clean and/or replace the filter  212  when it is dirty. Optionally, part or all of the sidewalls of the pre-motor filter chamber or housing  208  can be at least partially transparent so that a user can visually inspect the condition of the filter  212  without having to remove the cyclone bin assembly  136 . 
     In some embodiments, cyclone bin assembly  136  may extend below and partially surround pre-motor filter chamber  208 . In the illustrated embodiment, cyclone bin assembly  136  includes a cyclone chamber  144  aligned above pre-motor filter chamber  208  and a dirt collection chamber  148  extending below and forward of pre-motor filter chamber  208 . This may provide an enlarged dirt collection chamber  148  in a compact arrangement. In turn, the capacity of dirt collection chamber  148  may be increased which may permit surface cleaning apparatus  100  to be emptied less frequently. Still, in alternative embodiments, cyclone bin assembly  136  may be wholly positioned to one side of pre-motor filter chamber  208  (e.g. above pre-motor filter chamber  208 ). 
     Preferably, cyclone bin assembly  136  may be releasably connected to surface cleaning unit  112 . For example, surface cleaning unit  112  may include a locking mechanism having a locked position, in which cyclone bin assembly  136  may be inhibited from separating from surface cleaning unit  112 , and an unlocked position, in which cyclone bin assembly  136  may be freely removed from surface cleaning unit  112 . As exemplified, cyclone bin assembly  136  includes a locking mechanism  216  for releasably securing cyclone bin assembly  136  to surface cleaning unit  112 . In the example shown, locking mechanism  216  includes a locking member (or latch)  218  which may releasably engage a mating recess  220  in surface cleaning unit  112 . Recess  220  may be sized and positioned to receive locking mechanism  216  when cyclone bin assembly  136  is positioned in place on surface cleaning unit  112 . Locking mechanism  216  may interfere with the removal of cyclone bin assembly  136  from surface cleaning unit  112  by the interaction of locking member  218  with recess  220 . For example, a groove provided on latch  218  may engage the wall in which recess  220  is located. 
     Locking mechanism  216  may also include a lock-release actuator  224  which may be activated to move locking mechanism  216  to the unlocked position. Preferably, lock-release actuator  224  may be located on or proximate to handle  226  of cyclone bin assembly  136  so it may be actuated by a user using the same had as is used to hold handle  226 . This may permit a user to simultaneously grasp handle  226  and activate lock-release actuator  224 . As exemplified, a rear portion of handle  226  includes a lock-release actuator  224 . Activating lock-release actuator  224  may retract locking member  218  from recess  220  (e.g., by pivoting or rotating or translating latch  218  towards cyclone bin assembly  136 ) to place locking mechanism  216  in the unlocked position in which cyclone bin assembly  136  may be removed from surface cleaning unit  112 . 
     Referring now to  FIGS. 9 and 10 , cyclone bin assembly  136  may include one or more of an openable lid or bottom. This may provide access to empty dirt collection chamber  148  and/or cyclone chamber  144 . As exemplified, cyclone bin assembly  136  includes an openable lid  228 . Lid  228  may be movable between a closed position ( FIG. 9 ) in which lid  228  closes an upper end of cyclone bin assembly  136 , and an open position ( FIG. 10 ) in the upper end of cyclone bin assembly  136  is open. 
     Lid  228  of cyclone bin assembly  136  may be completely removed from cyclone bin assembly  136  in the open position. Alternatively, lid  228  may remain attached to cyclone bin assembly  136  in the open position. As exemplified, cyclone bin assembly  136  may include hinges  232  that pivotally connect lid  228  to cyclone bin assembly  136 . This may permit lid  228  to pivot to an open position while conveniently remaining connected to cyclone bin assembly  136 . 
     Wand Alignment 
     The following is a description of the wand alignment mechanism to assist in aligning the wand during insertion of the wand into the upper portion that may be used by itself in any surface cleaning apparatus or in any combination or sub-combination with any other feature or features disclosed herein. 
     Referring to  FIG. 5 , wand  180  may be removably mounted to upper portion  104  using any suitable mounting apparatus. Wand  180  and upper portion  104  may be configured to provide support and/or positioning or alignment of the wand  180  relative to the upper portion  104 . When connected to upper portion  104 , wand  180  may be stabilized to provide a driving connection between wand  180  and upper portion  104 . 
     In the example shown, upper portion  104  may be configured to receive an upstream end of wand  180  to connect wand  180  to upper portion  104 . When inserted, the outer wall of wand  180  and the inner wall of upper portion  104  may contact each other over a sufficient length to stabilize wand  180  so that upper portion  104  may provide a driving connection between wand  180  and surface cleaning head  108 . This may permit upper portion  104  to transmit forces applied to wand  180  (e.g. via handle  160  or directly to wand  180 ) to surface cleaning head  108  by way of, e.g., pivot joint  168 . For example, upper portion  104  may be rigidly connected to wand  180  to reduce or eliminate play between upper portion  104  and wand  180 . This may improve the handling of surface cleaning head  108  and thereby improve the user experience of apparatus  100 . 
     Reference is now to  FIG. 11 . As exemplified, wand  180  includes an upstream portion  1002  bordered by upstream end  192 . Upstream end  192  may define a wand air inlet for receiving dirty air to be communicated downstream through wand  180  to downstream end  188  ( FIG. 5 ). Further, upper portion  104  is shown including a downstream portion  1006  bordered by downstream end  1010 . As shown, downstream portion  1006  may include or surround an air outlet for discharging air received from surface cleaning head  108 , downstream (e.g. to wand  180 ). For example, downstream portion  1006  may comprise a cowl that surrounds and extends upwardly from the outlet of an air flow path extending through the surface cleaning head  108 . 
     Wand  180  may be sized and shaped to be partially received inside upper portion  104 . As exemplified, upstream portion  1002  of wand  180  may be removably receivable inside downstream portion  1006  of upper portion  104 . Downstream end  1010  of upper portion  104  may define an opening  1014  for receiving upstream end  192  of wand  180 . 
     When wand  180  is received inside upper portion  104 , wand  180  and upper portion  104  may form a connection that provides stability to wand  180 . For example, mating elements of upper portion  104  and wand  180  may engage upon reception of wand  180  inside upper portion  104 , whether automatically (i.e. without user action) by the insertion of wand  180  into upper portion  104  or by manual user-actuation of a retention member. Referring now to  FIGS. 11-13 , downstream portion  1006  may include inner walls  1018  having a transverse profile that corresponds to the transverse profile of outer walls  1022  of the upstream portion  1002  of wand  180 . For example, the transverse profile of inner walls  1018  may have a substantially similar size and shape as the transverse profile of the outer walls  1022 . Preferably, the transverse profile of outer walls  1022  is slightly smaller than the transverse profile of inner walls  1018  to provide a sufficient clearance to permit insertion and removal of wand  180  without play when want  180  is inserted into upper portion  104 . This may permit upstream portion  1002  to be easily inserted into downstream portion  1006 . 
     The transverse profile of inner walls  1018  and outer walls  1022  may have any suitable shape. For example, the transverse profiles may be circular, triangular, square or another regular or irregular shape. Preferably, the transverse profiles have a non-circular or irregular shape such that outer walls  1022  may fit between inner walls  1018  in only one orientation. This may force wand  180  to be specifically oriented with respect to upper portion  104  (e.g. to provide an intended orientation of handle  160  to surface cleaning head  108 ). In the example shown, the transverse profiles of inner walls  1018  and outer walls  1022  may be described as “egg-shaped”. That is, the transverse profiles are generally rounded and taper in width from one side to the other. 
     Alternatively, or in addition to the correspondence in transverse profiles of inner and outer walls  1018  and  1022 , wand  180  and upper portion  104  may include mating elements that limit the number of orientations in which upstream portion  1002  may be received in downstream portion  1006 . For example, wand  180  and upper portion  104  may collectively include one or more mating protrusions and recesses. 
     In the example shown, wand  180  includes a protrusion (or key)  1026  in upstream portion  1002  that protrudes outwardly along outer wall  1022 . Protrusion  1026  is configured to mate with (i.e. insert into) recess (or slot)  1030  formed in a lip  1034  of inner walls  1018  when upstream portion  1002  is received in downstream portion  1006 . When wand  180  is correctly oriented with respect to upper portion  104 , key  1026  will align with slot  1030  to allow upstream portion  1002  to be inserted into downstream portion  1006 . However, lip  1034  of downstream portion  1006  will interfere with key  1026  if attempting to insert upstream portion  1002  into downstream portion  1006  while wand  180  is incorrectly oriented with respect to upper portion  104  such that key  1026  is misaligned with slot  1030 . 
     Connecting wand  180  to upper portion  104  extends the airflow pathway from wand  180  upstream through surface cleaning head  108 . The connection may also connect one or more other mechanical elements, such as locking members or linkages, and/or electrical elements, such as electrical power connectors. In this case, there may be limited relative orientations between wand  180  and upper portion  104  which completes the airflow, mechanical and/or electrical connections. For this reason, it may be advantageous to limit the orientations in which the upstream portion  1002  can be received in downstream portion  1006 , preferably to a single orientation. 
     In the example shown, hose  124  is electrified and comprises part of a circuit extending from surface cleaning unit  112  to surface cleaning head. Accordingly, surface cleaning unit  112  may be provided with the electrical cord or an on board power source and an electrical component in the surface cleaning head  108  may be powered via the hose  124  and wand  180 . Accordingly, wand  180  may provide an electrified air flow conduit for conducting electricity along the length of wand  180 . As exemplified, upstream portion  1002  of wand  180  includes an electrical connector  1038 , and downstream portion  1006  of upper portion  104  includes a mating electrical connector  1042 . Electrical connectors  1038  and  1042  may be any suitable mating electrical connectors, such as for example a male connector (or plug) and a female connector (or jack). Further, electrical connectors  1038  and  1042  may connect any number of electrical conductors (e.g. from 1 to 100 conductors). As exemplified, each of connectors  1038  and  1042  connects three electrical conductors  1046 . Upstream and downstream portions  1002  and  1006  may each include any number of mating electrical connectors, each of which may connect different electrical conductors. 
     In some cases, electrical connectors  1038  and  1042  may be somewhat fragile. For example, electrical connectors  1038  and  1042  may suffer damage if subjected to certain stresses. In one aspect, the stability provided by upper portion  104  to wand  180  may advantageously reduce stresses on electrical connectors  1038  and  1042 . For example, mating elements of upper portion  104  and wand  180 , other than electrical connectors  1038  and  1042  (such as key  1026  and slot  1030 , and/or the corresponding transverse profiles of walls  1018  and  1022 ) may provide stability (such as resistance to relative rotational movement between wand  180  and upper portion  104 ) which might otherwise be borne by electrical connectors  1042  and  1046 . 
     Preferably, once wand  180  is connected to upper portion  104 , wand  180  remains connected to upper portion  104  until wand  180  is selectively disconnected from upper portion  104 . For example, the connection between wand  180  and upper portion  104  may be maintained by friction which may be overcome by sufficient force, or may be maintained by one or more retentive elements which may be selectively disengaged. Wand  180  may include a locking mechanism that automatically engages downstream portion  1006  when upstream portion  1002  is inserted into downstream portion  1006 . When the locking mechanism is engaged with downstream portion  1006 , upstream portion  1002  cannot be withdrawn from downstream portion  1006  unless the locking mechanism is unlocked. This may prevent the wand from  180  from disconnecting from upper portion  104  while wand is used to maneuver surface cleaning head  108 , for example. 
     Reference is now made to  FIG. 11 . As exemplified, wand  180  includes a locking member  1050  and upper portion  104  includes an opening  1054 . Locking member  1050  may be sized and positioned to automatically project through opening  1054  after upstream portion  1002  is properly inserted into downstream portion  1006 . Thereafter, upstream portion  1002  cannot be disconnected from downstream portion  1006  without withdrawing locking member  1050  from opening  1054 . An actuator, e.g. button  1058 , is provided to selectively withdraw locking member  1050  from opening  1054 , and permit upstream portion  1002  to be freely separated from downstream portion  1006 . 
     Optionally, wand  180  may remain connected with upper portion  104  even while the connection is unlocked. For example, if upstream portion  1002  is received in downstream portion  1006 , then the contact between wand  180  and upper portion  104  may retain wand  180  in upper portion  104  even while the locking mechanism for locking the connection is unlocked. In this circumstance, upper portion  104  may be configured to support wand  180  in an upright position. This may permit a user to release control of wand  180  while unlocking the locking mechanism, without the risk of wand  180  toppling over. As exemplified, downstream portion  1006  of upper portion  104  surrounds upstream portion  1002  of wand  180  when upstream portion  1002  is received in downstream portion  1006 . Preferably, upper portion  104  surrounds a sufficient height of wand  180  to provide support to wand  180  to rest in the upright position. For example, upper portion  104  may surround any portion of the wand and may surround the entire wand. As exemplified, upper portion may surround between 10 percent and 30 percent of the total height of wand  180  (measured from upstream end  192  to downstream end  188 ), and more preferably about 20 percent of the total height of wand  180 . 
     Referring now to  FIG. 4 , wand  180  and surface cleaning unit  112  are shown connected to upper portion  104 . As shown, downstream end  1010  of upper portion  104  extends well above upstream end  192  of wand  180 . As exemplified, upstream end  192  is positioned proximate a lower end  1062  of surface cleaning unit  112  and well below upper end  1066  of surface cleaning unit  112  (when both surface cleaning unit  112  and wand  180  are connected to upper portion  104 ). It will be appreciated that upstream end  192  may seat against or in the outlet end of pivot joint  168 . 
     When wand  180  is connected to upper portion  104 , the airflow pathway may extend from dirty air inlet  116  through surface cleaning head  108 , through pivot joint  168 , optionally through upper portion  104  if upstream end  192  is positioned above the outlet end of pivot joint  168 , and into wand  180 . Preferably, at least the portion of the airflow pathway extending between surface cleaning head  108  and wand  180  is substantially air-tight to preserve the suction generated by suction motor  128 . Optionally, a bleed valve (not shown) may be provided to reduce suction for cleaning certain cleaning surfaces. In some embodiments, wand  180  may form an airtight seal with the airflow passage when connected to upper portion  104 . As exemplified, upstream end  192  of wand  180  may be urged against a seal  1070  (e.g. O-ring) surrounding air outlet  1074  of upper portion  104  when wand  180  is connected to upper portion  104 . Seal  1070  may prevent entry or escape of air through the interface between wand  180  and upper portion  104 . 
     Reference is now made to  FIG. 11 . As exemplified, lower portion  1002  of wand  180  has a transverse cross-section that is sized and shaped to form a tight fit inside downstream portion  1006  of upper portion  104 . In some cases, it may be difficult for a user to insert one element into another where the fit between those elements is tight. For example, precise alignment requiring fine motor skills may be required for those elements to be connected. In some embodiments, wand  180  and/or upper portion  104  may be configured to make inserting wand  180  into upper portion  104  easier and faster. 
     In the example shown, upstream portion  1002  of wand  180  includes a lower section  1078 , and an upper section  1082 . Lower section  1078  is bordered by upstream end  192 , and upper section  1082  is downstream of lower section  1078 . The transverse section of upper section  1082  may be sized and shaped to provide a tight fit with downstream portion  1006  of upper portion  104 . At the same time, lower section  1078  may have a substantially smaller transverse section, which may provide a greater margin for alignment error when firstly inserting lower section  1078  into opening  1014 . Accordingly, a user may insert upstream end  192  into upper portion  104 . This is facilitated by the clearance between the facing walls of upstream end  192  and upper portion  104 . Some or all of the weight of the wand  18 - 0  may then be supported by upper portion  104 . The user may then rotate wand  180  to the required insertion orientation and complete the insertion of wand  180  into upper portion  104  by inserting part or all of upper section  1082 . The stepwise insertion of a narrower lower section  1078  into upper portion  104  followed by a wider upper section  1082  may make inserting upstream portion  1002  into upper portion  104  easier for a user. Once lower section  1078  is inserted into opening  1014 , lateral movements of wand  180  are substantially constrained, by the interaction of lower section  1078  with inner walls  1018 , to positions that are in close proximity to the comparatively narrower range of positions that will allow upper section  1082  to pass through opening  1014  into downstream portion  1006 . Such constraint may make finding the correct position faster and easier for a user because the constraint increases the proportion of available positions that will allow upper section  1082  to enter downstream portion  1006 . 
     Alternatively, or in addition to a narrower lower section  1078 , downstream end  1010  of upper portion  104  at opening  1014  may be transversely inclined (or “sloped”). As shown, a front side  1086  of opening  1014  extends higher (i.e. further downstream) than the rear side  1090 . This may permit a user to more easily locate upstream portion  1002  into opening  1014 . In use, the user may simply move front side  1094  of upstream portion  1002  against front side  1086  of opening  1014  to align upstream portion  1002  with opening  1014 , and then move upstream portion  1002  downwardly through the remainder of opening  1014 . In this way, front side  1086  of opening  1014  may act as a guide for directing upstream portion  1002  downwardly into the remainder of opening  1014 . This may be easier to perform than having to maneuver upstream portion  1002  through a transversely uninclined (i.e. horizontal) opening, since such an opening forms a complete periphery at its uppermost edge. If upstream portion  1002  includes a narrower lower section  1078 , then preferably, lower and upper sections  1078  and  1082  may be flush along front side  1094  to permit upstream portion  1002  to slide downwardly through opening  1014 , as described above, without interference by an overhanging lip of upper section  1082 . 
     Reference is now made to  FIG. 14 . Alternately, or in addition, sloped opening  1014  may help to correct for rotational misalignment of wand  180  with respect to upper portion  104 . After at least partially inserting lower section  1078  of upstream portion  1002  of wand  180  through opening  1014  of upper portion  104 , if wand  180  is not properly oriented in rotation (i.e. rotationally misaligned) with opening  1014 , then a lip  1098  of upper section  1082  may contact downstream end  1010  at opening  1014 . In this case, the downward force F w  of wand  180 , whether gravity or user applied to the point of contact between lip  1098  and downstream end  1010 , is met with a reactionary force F N  by sloped downstream end  1010 . As shown, reactionary force F N  includes a vertical component of force F V  in opposition to downward for F W  in addition to a horizontal component of force F H . The horizontal component of force F H  urges the wand  180  to rotate back into alignment. For example, if wand  180  is rotated out of alignment in the clockwise direction  1102  then the component of force F H  urges the wand  180  to rotate counter-clockwise into alignment. In this way, sloped opening  1014  interacts with upper section  1082  of upstream portion  1002  to urge wand  180  into proper alignment for insertion into opening  1014 . 
     Wand Locking Mechanism 
     The following is a description of the wand locking mechanism that may be used by itself in any surface cleaning apparatus or in any combination or sub-combination with any other feature or features disclosed herein. 
     Reference is now made to  FIG. 11 . Preferably, once wand  180  is connected to upper portion  104 , wand  180  remains connected to upper portion  104  until wand  180  is selectively disconnected from upper portion  104 . The connection between wand  180  and upper portion  104  may be maintained by one or more retentive elements of a locking mechanism, which may be selectively disengaged. When the locking mechanism is engaged, upstream portion  1002  cannot be withdrawn from downstream portion  1006  unless the locking mechanism is unlocked. This may prevent the wand from  180  from disconnecting from upper portion  104  while wand  180  is used to maneuver surface cleaning head  108 , for example. 
     Reference is now made to  FIGS. 11 and 22 .  FIG. 22  shows a partial view of wand  180  including upstream portion  1002  with outer wall  1022  removed to expose the inner locking mechanism (or “wand lock”)  1106 . Wand lock  1106  may include a locking member that releasably engages upper portion  104  to selectively secure wand  180  to upper portion  104  in a locked position. As exemplified, wand lock  1106  includes a plunger  1050  which may extend through opening  1054  of downstream portion  1006  to obstruct the withdrawal of upstream portion  1002  from downstream portion  1006 . Further, plunger  1050  may be retractable to withdraw from opening  1054  and cease obstructing the withdrawal of upstream portion  1002  from downstream portion  1006 . 
     As exemplified, plunger  1050  is positioned in a slot  1110  for translation between an extended position (shown), and a retracted position. A resilient member, such as spring  1114  ( FIG. 23 a   ) may act upon plunger  1050  to bias plunger  1050  toward the extended or locked position. In the extended position, an end portion  1118  of plunger  1050  protrudes from slot  1110  through an opening  1122  in outer wall  1022 . In the retracted position, end portion  1118  of plunger  1050  is at least partially withdrawn back into slot  1110 . 
     Preferably, wand lock  1106  is configured to automatically lock wand  180  to upper portion  104 , upon insertion of wand  180  into upper portion  104 . For example, the locking member of wand lock  1106  may automatically engage upper portion  104  upon the insertion of upstream portion  1002  into downstream portion  1006 , thereby securing wand  180  to upper portion  104 . In some cases, the locking member may translate laterally (i.e. substantially perpendicularly to the airflow path) to releasably engage the upper portion  104 . As exemplified, plunger  1050  may automatically translate (or “extend”) laterally outwardly through opening  1054  in downstream portion  1006  upon the insertion of upstream portion  1002  into downstream portion  1006 , without requiring further user action. 
     In the example shown, end portion  1118  of plunger  1050  includes a lower side  1126  and an opposite upper side  1130 . Lower side  1126  includes a sloped face  1134 . First, plunger  1050  may be in the extended position while upstream portion  1002  is withdrawn from downstream portion  1006 . In the extended position, end portion  1118  including sloped face  1134  of lower side  1126  may protrude through opening  1122 . When inserting upstream portion  1002  into downstream portion  1006 , sloped face  1134  of lower side  1126  may make contact with downstream end  1010  at opening  1014  during insertion. For example, there may be less space between outer and inner walls  1022  and  1018  than the distance by which end portion  1118  protrudes through opening  1122  in the extended position. Downstream end  1010  may cam along sloped face  1134  forcing plunger  1050  to retract against the bias of spring  1114  until tip  1138  of plunger  1050  meets inner walls  1018 . Upon further insertion, plunger  1050  may align with opening  1054  and translate laterally under the bias of spring  1114  through opening  1054 . 
     When plunger  1050  is in the extended position and extending through opening  1054 , wand  180  may not be withdrawn from upper portion  104  without first at least partially retracting plunger  1050 . As exemplified, plunger  1050  includes an upper side  1130 . Upper side  1130  is shown including a sloped outboard face  1142  bordered by tip  1138 , and an unsloped (or less sloped) inboard face  1146  inboard of outboard face  1142 . Preferably, at least a portion of inboard face  1146  projects through opening  1054  in the extended position. In this case, inboard face  1146  may contact an upper wall of opening  1054  if upstream portion  1002  is attempted to be withdrawn from downstream portion  1006  without first retracting plunger  1050 . In turn, the slope of inboard face  1146  (or lack thereof) may be insufficient for the upper wall of opening  1054  to cam along inboard face  1146  to withdraw plunger  1050 . Accordingly, upstream portion  1002  cannot be withdrawn from downstream portion  1006 ; wand lock  1106  is in the locked (or “engaged”) position. 
     Wand lock  1106  may be unlocked by a mechanical, electrical, or electromechanical device in response to a user action. For example, wand lock  1106  may include a wand release actuator which operates to unlock wand lock  1106 . When wand lock  1106  is in the unlocked position, wand  180  may be freely removable from upper portion  104 . 
     As exemplified, upper portion  104  may terminate well below waist height. For example, upper portion may be 12-14 inches tall. An advantage of a shorter upper member is that it facilitates the insertion of wand  180  into upper portion  104 . In order to avoid a user having to bend over to release wand  180  while enabling wand  180  to be locked to upper portion  104 , an actuator  1058  may be provided at a height which may be actuated by a user while standing upright. An actuator, such as button  1058 , may be drivingly connected to lock  1106  by a longitudinally extending member, such as shaft  1150 . The actuator and shaft, as well as the linking member, may be provided as part of, and removable with, wand  180 . Accordingly, by incorporating the lock and actuator into wand  180 , upper portion  104  may be shorter. 
     For example, in the embodiment of  FIG. 22 , wand lock  1106  includes a longitudinally extending transmission member that drivingly connects the wand release actuator and the locking member. For example, the transmission member may be translatable downwardly to move the wand lock  1106  into the unlocked position. Moving the transmission member downwardly may cause the locking member to move laterally to a disengaged position, and set the wand lock  1106  in the unlocked position. 
     In the example shown, a button  1058  is mounted to wand  180  that drives a shaft  1150  to translate toward plunger  1050 . A biasing member, such as spring  1152  may bias shaft  1150  upwardly into a retracted position. Shaft  1150  may interact with plunger  1050  to move plunger  1050  into a retracted position, and thereby permit the upper wall of opening  1054  to clear at least inboard face  1146  (i.e. to engage with sloped outboard face  1142  instead, or to clear plunger  1050  altogether). As exemplified, plunger  1050  includes an upwardly-facing face  1154 , and shaft  1150  includes a lower portion  1158  including a downwardly-facing face  1162 . Faces  1154  and  1162  may be positioned to meet when shaft  1150  is translated downwardly toward plunger  1050  (as shown in  FIG. 23 b    when button is partially pressed to move the lock to the unlocked position). Faces  1154  and  1162  may be shaped to provide a caming action that retracts plunger  1050  against the bias of spring  1114  as shaft  1150  is further translated toward plunger  1050 . In the example shown, each of faces  1154  and  1162  are correspondingly sloped. As shaft  1150  is translated downwardly, face  1158  of shaft  1150  cams along face  1154  of plunger  1050  causing plunger  1050  to retract to the retracted position. In the retracted position, the upstream portion  1002  may be withdrawn from downstream portion  1006 ; the wand lock is unlocked (or “disengaged”). The upper wall of opening  1054  may be able to clear at least inboard face  1146  which was preventing the withdrawal in the locked condition. 
     Preferably, wand lock  1106  may remain in the unlocked (or “disengaged”) position after button  1058  is released. This may permit a user to use the same hand to activate button  1058  (unlocking wand  180 ) and to subsequently remove wand  180  from upper portion  104 . In the example shown, shaft  1150  may be biased (e.g. by a resilient element such as spring  1152 ) upwardly. When plunger  1050  is in the retracted position, shaft  1150  may obstruct plunger  1050  from extending under the bias of spring  1114 , and plunger  1050  may obstruct shaft  1150  from retracting upwardly. As exemplified, plunger  1050  includes a lip  1166  below face  1154 , and shaft  1150  includes a lip  1170  above face  1162 . Further, lower face  1162  may move past upper face  1154  during downward translation of shaft  1150 . When this occurs, plunger  1050  translates laterally outwardly a short distance moving lips  1166  and  1170  into contact. The contact between lips  1166  and  1170  prevents shaft  1150  from withdrawing upwardly. Further, the position of lower portion  1158  in front of plunger  1050  obstructs plunger  1050  (as shown in  FIG. 23 c   ) from further translation toward the extended position. Accordingly, the lock is maintained in the unlocked position. 
     Preferably, wand lock  1106  may be freed from maintaining the unlocked position upon removing and/or reinserting wand  180  into upper portion  104 . For example, shaft  1150  and plunger  1050  may be disentangled upon the withdrawal or reinsertion of upstream portion  1002  out of or into downstream portion  1006 . As exemplified, sloped outboard face  1142  and a portion of sloped lower face  1134  of plunger  1050  may protrude outwardly through opening  1122  in upstream portion  1002 , when plunger  1050  is in the retracted position. This may permit the upper wall of opening  1054  to cam sloped outboard face  1142  during withdrawal of upstream portion  1002  from downstream portion  1006  to further retract plunger  1050 . This moves lip  1166  of plunger  1050  out of contact with lip  1170  of shaft  1150  (as shown in  FIG. 23 d   ), allowing shaft  1150  to retract upwardly. After plunger  1050  clears the downstream end  1010  of upper portion  104 , plunger  1050  may extend under the bias of spring  1114  to the extended position. 
     Wand lock  1106  may also be maintained in the unlocked position while wand  180  is removed from upper portion  104 . For example, button  1058  may be depressed to retract plunger  1050  and entangle shaft  1150  with plunger  1050  while wand  180  is removed from upper portion  104 . In this case, reinserting wand  180  into upper portion  104  may release wand lock from the unlocked position. As exemplified, a portion of sloped lower face  1134  of plunger  1050  may protrude outwardly through opening  1122  in upstream portion  1002 , when plunger  1050  is in the retracted position. This may permit the downstream end  1010  at opening  1014  to cam sloped lower face  1134  during insertion of upstream portion  1002  into downstream portion  1006  to further retract plunger  1050 . This moves lip  1166  of plunger  1050  out of contact with lip  1170  of shaft  1150  (as shown in  FIG. 23 d   ), allowing shaft  1150  to retract upwardly. Once plunger  1050  aligns with opening  1054  in downstream portion  1006 , plunger  1050  may translate laterally outwardly under the bias of spring  1114  to the extended position. 
     Wand Lock Release Actuator 
     The following is a description of the wand lock release actuator that may be used by itself in any surface cleaning apparatus or in any combination or sub-combination with any other feature or features disclosed herein. 
     In some embodiments, the locking mechanism (e.g. wand lock  1106 ) that prevents wand  180  from being separated from upper portion  104  after they are connected, may be released by a wand lock release actuator. The actuator may have a mechanical, electrical, or electromechanical connection to the wand lock. Preferably, the actuator may be positioned remotely from upper portion  104  at a position above upper portion  104  toward handle  160  ( FIG. 5 ). For example, the actuator may be positioned above upper portion  104  on wand  180  or on handle  160 . In some cases, the actuator may be positioned between a user&#39;s knee height and chest height, and more preferably between a user&#39;s thigh height and waist height. This may reduce or eliminate the need for a user to bend over to activate the actuator to release the wand lock and separate the wand  180  from the upper portion  104  (e.g. to use the surface cleaning apparatus  100  in an above-floor cleaning mode). 
     Referring to  FIGS. 11 and 22 , as exemplified, a button  1058  may be positioned at approximately a midpoint along the length of wand  180 . Button  1058  is an example of a lock release actuator. This may generally correspond to a height of a user&#39;s thighs. As shown, button  1058  may be substantially parallel with an upper end  1066  of surface cleaning unit  112 . Button  1058  is drivingly connected to the plunger  1050  by shaft  1150 . 
     The lock release actuator may be connected to wand  180 , and removable from upper portion  104  and surface cleaning unit  102  when wand  180  is separated from upper portion  104  and surface cleaning unit  102  (e.g. for use in an above-floor cleaning mode). Similarly, a longitudinally extending transmission member drivingly connecting the lock release actuator to the locking member of wand lock  1106  may be mounted to wand  180  and removable from upper portion  104  and surface cleaning unit  102  when wand  180  is separated from upper portion  104  and surface cleaning unit  102 . For example, wand lock  1106  in its entirety may be mounted to wand  180  and removable from upper portion  104  and surface cleaning unit  102  when wand  180  is separated from upper portion  104  and surface cleaning unit  102 . This may advantageously allow surface cleaning apparatus  100  to be easily reconfigured into different modes of operation. For example, when surface cleaning unit  112  is unmounted from (removed from) upper portion  104 , the wand lock  1106  may remain with wand  180  to allow wand  180  to remain releasably connected to upper portion  104 . 
     In the example shown, wand lock  1106  including button  1058 , shaft  1150 , and plunger  1050  are all connected to wand  180  independent of surface cleaning unit  112  and upper portion  104 , and remain so connected after surface cleaning unit  112  and upper portion  104  are separated from wand  180 . 
     Surface Cleaning Unit Mounting Structure 
     The following is a description of the surface cleaning unit mounting structure that may be used by itself in any surface cleaning apparatus or in any combination or sub-combination with any other feature or features disclosed herein. 
     Reference is now made to  FIG. 5 . Surface cleaning unit  112  may be removably mountable to one or more of upper portion  104  and wand  180 . Preferably, surface cleaning unit  112  may be mounted to upper portion  104  independent of wand  180 , such that surface cleaning unit  112  may be mounted and dismounted from upper portion  104  without adjusting the position of wand  180  or removing wand  180 . Accordingly, for example, wand  180  may remain in upper portion  104  while surface cleaning unit  112  is mounted to or removed from upper portion  104 . 
     Alternately, or in addition, when surface cleaning unit  112  is mounted to upper portion  104 , upper portion  104  may stabilize surface cleaning unit  112  (e.g. surface cleaning unit  112  may remain in a fixed position on upper portion  104  as upper portion  104  is manipulated to maneuver surface cleaning head  108 ). For example, upper portion  104  may inhibit translational movement of surface cleaning unit  112  along upper axis  164  ( FIG. 1 ) toward surface cleaning head  108 , and/or may inhibit rotational movement of surface cleaning unit  112  around upper axis  164 . 
     Accordingly, surface cleaning unit  112  may be mounted on the exterior of upper portion  112  by two mounting members wherein the mounting members are provided a two longitudinally (e.g., along axis  164 ) spaced apart locations wherein at least one of the two mounting members provides lateral stability as upper portion  104  is manipulated to maneuver surface cleaning head  108 . It will be appreciated that more than two mounting members may be provided. 
     Surface cleaning unit  112  may be slidably receivable on one or both of the mounting members. For example, surface cleaning unit  112  may have one or more recess to receive one of the mounting members therein. Accordingly, if one of the mounting members comprises a pair of laterally extending portions (e.g., left and right laterally extending wings that extend outwardly from opposed sides of the upper portion, or a mounting member provided on the front or rear of the exterior of the upper portion which has left and right laterally extending wings), then the surface cleaning unit  112  may have one or two groves in which the laterally extending position may be received. 
     One of the mounting members may have a sufficient height such that surface cleaning unit remains in a fixed position if wand  180  is removed and/or surface cleaning unit  112  is unlocked for removal from upper portion. For example, if the mounting member comprises laterally extending portions that are received in a recess, groove or the like then the engagement between abutting surfaces of the laterally extending portions and the recess, groove or the likes may dimensionally stabilize surface cleaning unit  112  in position in the unlocked position and with the wand removed. 
     Referring to  FIGS. 15-18 and 29-33 , surface cleaning unit  112  and upper portion  104  may include one or more mounting elements or members for connecting surface cleaning unit  112  to upper portion  104 . For example, the mounting elements may include outwardly projecting mounting members or wings and corresponding mounting recesses for receiving those mounting members. 
     As exemplified, upper portion  104  includes outwardly projecting wings  1174   a  and  1174   b . Wings  1174  are examples of mounting members. As shown, wings  1174  may extend laterally from a front side  1178  of upper portion  104 . Although upper portion  104  is shown including two mounting members, in alternative embodiments, upper portion  104  may include any suitable number of mounting members. For example, upper portion  104  may include between one wing  1174  and ten wings  1174 , which may extend in any number of directions. Further, wings  1174  may each be discrete elements, or they may be integrally formed as are  1174   a  and  1174   b  in the example shown. 
     As exemplified, surface cleaning unit  112  includes recesses  1182   a  and  1182   b . Each recess  1182  may include an opening  1186  in a bottom surface  1190  of surface cleaning unit  112 . Recesses  1182  may be sized and positioned to receive wings  1174 . For example, surface cleaning unit  112  may be positioned above upper portion  104  and lowered to slide wings  1174  into recesses  1182 . Thereafter, surface cleaning unit  112  may be separated from upper portion  104  by moving surface cleaning unit  112  vertically away from upper portion  104  to remove wings  1174  from recesses  1182 . 
     Although surface cleaning unit  112  is shown including two recesses  1182 , in alternative embodiments, surface cleaning unit  112  may include any suitable number of recesses for receiving some or all of the mounting members of upper portion  104 . Further, the arrangement of recesses and protruding mounting members may be reversed. Each of surface cleaning apparatus  112  and upper portion  104  may include one or more recesses and mounting members sized and positioned to mate with one another. 
     Optionally, openings  1186  to recesses  1182  may be shaped to make it easier for a user to insert wings  1174  into recesses  1182 . In some cases, mating recesses  1182  over wings  1174  may include lowering surface cleaning unit  112  onto upper portion  104 . The openings  1186  to recesses  1182  on the bottom surface  1190  of surface cleaning unit  112  may be well below a user&#39;s eye-level and obscured from view. This may make aligning openings  1186  with recesses  1182  more difficult. 
     As exemplified, each recess  1182  may be flared in a lower portion  1194  of the recess  1182  to provide an enlarged opening  1186 . Enlarged openings  1186  may make aligning openings  1186  over wings  1174  less difficult. Once wings  1174  enter the enlarged openings  1186 , surface cleaning unit  112  may self-align as surface cleaning unit  112  is lowered further and wings  1174  enter the narrower upper portions  1198  of recesses  1182 . 
     In the example shown, at least upper portion  1198  of each recess  1182  has a sectional profile that closely corresponds to the sectional profile of respective mating wings  1174 . This may provide a tight interface between recesses  1182  and wings  1174  for stabilizing surface cleaning unit  112  on upper portion  104 . 
     The fit between wings  1174  and recesses  1182  may stabilize surface cleaning unit  112  from rotating in all directions. This may prevent surface cleaning unit  112  from tipping over, e.g. when upper portion  104  is manipulated to maneuver surface cleaning head  108 . Further, wings  1174  may support surface cleaning unit  112  from translating toward surface cleaning head  108 . For example, one or more of recesses  1182  may include an end wall  1202  bordering upper portion  1198 . Wings  1174  may insert far enough into recesses  1182  that an upper surface  1204  of at least one of wings  1174  contacts an end wall  1202 . This contact may inhibit further translation of surface cleaning unit  112  toward surface cleaning head  108 . Accordingly, for example, if wand  180  is removed and/or surface cleaning unit  112  is unlocked for removal from upper portion, then surface cleaning unit  112  may remain in position on upper portion  104 . 
     In alternative embodiments, different mounting element(s) inhibit movement of surface cleaning unit  112  toward surface cleaning head  108 . In this case, recesses  1182  may be open ended (i.e. without end walls  1202 ), wings  1174  may not reach an end wall  1202 , or both. Instead the different mounting element(s) may inhibit movement of surface cleaning unit  112  toward surface cleaning head  108 . 
     Reference is now made to  FIGS. 15, 17, and 20 . In addition to, or instead of wings  1174  and recesses  1182 , surface cleaning unit  112  may include a different mounting member that engages downstream end  1010  of upper portion  104 . As exemplified, surface cleaning unit  112  includes a clip  1206 . Clip  1206  is an example of a mounting member. Clip  1206  may extend downwardly in spaced apart relation from a rear surface  1210  of surface cleaning unit  112  forming a slot  1214  for receiving a portion of downstream end  1010  of upper portion  104 . 
     In use, surface cleaning unit  112  may be lowered onto upper portion  104  such that a front side  1178  of downstream portion  1006  enters slot  1214 , and clip  1206  enters upper portion  104 . Clip  1206  may grasp front side  1178  of upper portion  104  to inhibit surface cleaning unit  112  from rotating forwardly, over surface cleaning head  108 , or rearwardly. In some cases, upper portion  104  may abut upper end  1218  of slot  1214  such that the weight of surface cleaning unit  112  may be supported on downstream end  1010  of upper portion  104 . Clip  1206  may be disconnected from upper portion  104  by raising surface cleaning unit  112  vertically away from upper portion  104 . Accordingly, upper portion  104  provides a support on which the surface cleaning unit  112  (clip  1206 ) seats when mounted to upper portion  104 . 
     As shown in  FIG. 18 , a clearance  1222  may be provided between inner wall  1018  of upper portion  104  and outer wall  1022  of wand  180 , toward the front side  1178  of upper portion  104 , when wand  180  is inserted into upper portion  104 . Clearance  1222  may provide space for clip  1206  to be received in upper portion  104  simultaneously with wand  180 . Further, either of clip  1206  or wand  180  may be removed from upper portion  104  while the other remains inserted in upper portion  104 . This may make reconfiguring surface cleaning apparatus  100  into different cleaning modes quick and easy. 
     Reference is now made to  FIGS. 11, 13, 15, and 20 . Alternatively, or in addition to wings  1174 , recesses  1182 , and clip  1206 , wand  180  may include mounting members for supporting surface cleaning unit  112  and or dynamically stabilizing or assisting in dynamically stabilizing surface cleaning unit  112  on upper portion  1104 . Accordingly, for example, the mounting members of wand  180  enhance stability of surface cleaning unit  112  when both wand  180  and surface cleaning unit  112  are connected to upper portion  104 . For example, mounting members of wand  180  may inhibit the rotation and/or the translation forward of surface cleaning unit  112 , e.g. when upper portion  104  and/or wand  180  are manipulated to maneuver surface cleaning head  108 . 
     As exemplified, wand  180  may include wings  1226   a  and  1226   b . Wings  1226  are examples of mounting members. Further, surface cleaning unit  112  may include arms  1230   a  and  1230   b  for at least partially surrounding wings  1226 . As shown, each arm  1230  may define a slot  1234  for receiving a wing  1226 . Preferably, slots  1234  are open ended. This may permit wings  1226  to be received from above or below slots  1234 . For example, if surface cleaning unit  112  is connected to upper portion  104 , then wings  1226  may enter and exit slots  1234  through the open upper end  1238  of slots  1234 , as wand  180  is lowered into upper portion  104  or raised away from upper portion  104 . Further, if wand  180  is connected to upper portion  104 , then wings  1226  may enter and exit through slots  1234  through the open bottom end  1242  of slots  1234 , as surface cleaning unit  112  is lowered onto upper portion  104  or raised away from upper portion  104 . 
     Slots  1234  may be shaped to make aligning wings  1226  with slots  1234  easier. As exemplified, each end  1238  and  1242  of slots  1234  may be flared to provide a widened opening for easier alignment with wings  1226 . Further, each slot  1234  may include a narrow region  1246  between upper and lower ends  1238  and  1242 . Preferably, narrow region  1246  may make contact with wings  1226  when wings  1226  are received in slots  1234 . As exemplified, each of wings  1226  includes a front surface  1250  that faces forward toward surface cleaning unit  112  (when surface cleaning unit  112  and wand  180  are connected to upper portion  104 ), and an opposite rear face  1254 . In use, when wings  1226  are received in slots  1234 , slots  1234  may contact at least a portion of rear faces  1254  of wings  1226 . This may permit arms  1230  to inhibiting surface cleaning unit  112  from tilting forwardly over surface cleaning head  108 . 
     Alternatively, or in addition to providing support for surface cleaning unit  112 , the interaction between wings  1226  and arms  1230  may help to support wand  180  in an upright position. Wand  180  may be releasably securable to upper portion  104 . For example, a wand lock may be releasably engaged to secure wand  180  to upper portion  104 . However, in some embodiments, after the wand lock is disengaged, upper portion  104  may not provide good support to maintain wand  180  in position. For example, wand  180  may tip over after the wand lock is disengaged if no further support is provided. This may be exacerbated where the wand lock remains disengaged after a user ceases interaction with a wand lock release actuator. In this case, when a user activates the wand lock release actuator, the user may release control of wand  180 , such that wand  180  may fall over if no further support is provided to keep wand  180  in position. Such further support may be provided by arms  1230  which may receive wings  1226  to support wand  180  in an upright position, e.g. when wand lock is unlocked. This may provide a user with time to develop a proper grip on wand  180  after unlocking the wand lock. 
     In operation, a user may position surface cleaning unit  112  adjacent upper portion  104  and above upper wings  1226  and above lower wings  1174 . Slots  1234  may be generally aligned with upper wings  1226  and recesses  1182  may be generally aligned with lower wings  1174 . This is the position shown in  FIG. 31 . Surface cleaning unit  112  may then be lowered. As surface cleaning unit  112  is lowered, arms  1230  extend to surround upper wings  1226  and lower wings  1174  commence to be received in recesses  1182 . This is the position shown in  FIG. 32 . Continual lowering of surface cleaning unit to the mounted position shown in  FIG. 33  results in surface cleaning unit being seated on lower wings  1174 , clip  1206  being received in upper portion  104  and arms  1230  of the surface cleaning unit surrounding upper wings  1226  of the wand  180 . 
     Another example is provided in the embodiment of  FIGS. 25 and 27 . As shown, upper portion  104  may include mounting members  1174 , formed as wings, which are sized and positioned to be received in recesses of mounting member  1502  provided on a rear surface  1210  of surface cleaning unit  112 . Alternatively, or in addition, upper portion  104  may include a second mounting member  1504  sized and positioned to receive wheel  1506  which is supported on surface  1210 . In use, surface cleaning unit  112  may be positioned with mounting member  1502  and wheels  1506  aligned above mounting members  1174  and  1504 , and the lowered, so that mounting member  1502  slidingly engages mounting member  1174  and wheel  1506  seats on mounting member  1504 . 
     Surface Cleaning Unit Locking Mechanism 
     The following is a description of the surface cleaning unit locking mechanism that may be used by itself in any surface cleaning apparatus or in any combination or sub-combination with any other feature or features disclosed herein. 
     Preferably, once surface cleaning unit  112  is connected to upper portion  104 , surface cleaning unit  112  remains connected to upper portion  104  until surface cleaning unit  112  is selectively disconnected from upper portion  104 . The connection between surface cleaning unit  112  and upper portion  104  may be maintained by one or more retentive elements of a locking mechanism, which may be selectively disengaged. When the locking mechanism is engaged, surface cleaning unit  112  may not be separable from upper portion  104  unless the locking mechanism is unlocked. This may prevent the upper portion  104  from disconnecting from upper portion  104 , e.g. while upper portion  104  is used to maneuver surface cleaning head  108  or if surface cleaning apparatus  100  is carried by grasping surface cleaning unit  112 . 
     As discussed previously, upper portion  104  may terminate well below waist height. An advantage of a shorter upper member is that it facilitates the insertion of wand  180  into upper portion  104 . In order to avoid a user having to bend over to release surface cleaning unit  112  while enabling surface cleaning unit  112  to be locked to upper portion  104 , an actuator may be provided at a height which may be actuated by a user while standing upright. The actuator may be drivingly connected to lock by a longitudinally extending member, such as shaft. The actuator and shaft, as well as any linking member, may be provided as part of, and removable with, surface cleaning unit  112 . Accordingly, by incorporating the lock and actuator into surface cleaning unit  112 , upper portion  104  may be shorter. 
     Reference is made to  FIGS. 17, 20, and 21   a - d , where like part numbers refer to like parts in the other figures. As exemplified, surface cleaning unit  112  may include a locking mechanism  1258  that is substantially similar to wand lock  1106  describe above. Accordingly, the description below of locking mechanism  1258  is abbreviated so as not to unnecessarily repeat details and variants already described above. 
     In the example shown, locking mechanism  1258  may include an unlock actuator  1058  drivingly connected to a locking member  1050  by a longitudinally extending transmission member  1150 . Locking member  1050  may translate laterally outwardly to engage with upper portion  104 , placing locking mechanism  1258  into a locked position ( FIG. 21 a   ). Vertical translation of longitudinally extending transmission member  1150  toward locking member  1050  (e.g. by interaction with unlock actuator  1058 ) may urge locking member  1050  to translate laterally inwardly ( FIG. 21 b   ) to disengage with upper portion  104 , placing locking mechanism  1258  in an unlocked position ( FIG. 21 c   ). Once in the unlocked position, locking mechanism  1258  may remain unlocked until the surface cleaning unit  112  is withdrawn from upper portion  104  or reengaged with the upper portion  104 . The act of withdrawing or reengaging surface cleaning unit  112  with upper portion  104  may release locking mechanism  1258  from the unlocked position ( FIG. 21 d   ), allowing locking mechanism  1258  to move to the locked position when appropriate. 
     As exemplified, locking mechanism  1258  may be wholly connected to surface cleaning unit  112 . When surface cleaning unit  112  is removed from upper portion  104 , so too may locking mechanism  1258 , which may remain connected to surface cleaning unit  112 . In the example shown, locking mechanism  1258  is positioned behind rear surface  1210  of surface cleaning unit  112 . Locking member  1050  of locking mechanism  1258  is exemplified as a plunger which is extendable through an opening  1262  in rear surface  1210  of surface cleaning unit  112 . Locking member  1050  of locking mechanism  1258  may engage with a front side  1178  of upper portion  104 . As exemplified, front side  1178  includes an opening  1266 . Opening  1266  may be sized and positioned to receive locking member  1050  when locking mechanism  1258  is in the locked position. 
     Lock release actuator  1058  may be positioned in any suitable location. Preferably, lock release actuator  1058  is positioned proximate upper end  1066  of surface cleaning apparatus  112 . This may permit a user to activate lock release actuator  1058  (e.g. depressing a button actuator) with little or no bending over. Further, lock release actuator  1058  is preferably positioned proximate handle  160 . In some embodiments, this may permit a user to simultaneously grasp handle  160  and activate lock release actuator  1058 . In the example shown, lock release actuator  1058  is positioned on openable lid  228  of cyclone bin assembly  136 . As shown in  FIG. 23 , lock release actuator  1058  may extend through an opening  1270  in an inner surface of lid  216  for interacting with transmission member  1150 . When lid  216  is in an open position, as shown in  FIG. 23 , lock release actuator  1058  may disengage (e.g. separate from) transmission member  1150 . When lid  216  is in a closed position, lock release actuator  1058  may re-engage (e.g. reestablish contact with) transmission member  1150  for driving the translation of transmission member  1150 . 
     Preferably, locking mechanism  1258  inhibits vertical translation of surface cleaning unit  112  away from upper portion  104  (e.g. in the downstream direction) when locking mechanism  1258  is in the locked condition. However, in some embodiments, locking mechanism  1258  may not inhibit forward rotation (i.e. rotation over surface cleaning head  108 ) of locking mechanism  1258 , which in some circumstances may remove locking member  1050  from opening  1266  defeating locking mechanism  1258 . Therefore, surface cleaning apparatus  100  may include additional retentive elements for at least inhibiting forward rotation of surface cleaning unit  112  when connected to upper portion  104 . For example, one or both of surface cleaning unit  112  and upper portion  104  may include one or more mounting members, such as wings  1174  and/or clip  1206 , for mounting surface cleaning unit  112  to upper portion  104  and inhibiting at least forward rotation of surface cleaning unit  112 . 
     Alternate Attachments 
     The following is a description of alternate tools, such as cleaning tool, powered cleaning tools and power tools, such as a sander, a drill, a saw or a steam mop module, that may be attached, e.g., to the inlet end of wand  180  or the inlet end of handle  160 , and which may be used by itself in any surface cleaning apparatus or in any combination or sub-combination with any other feature or features disclosed herein. 
     In another example of the above floor cleaning mode that is exemplified in  FIG. 7 , the surface cleaning unit  112  can remain mounted on the upper portion  104  and the wand  180  can be detached from the upper portion  104  to provide an extended wand for above floor cleaning. Optionally, additional accessory tools may be coupled to the upstream end  192  of wand  180 , including for example), a cleaning brush  1512  (see  FIG. 28 a   ), optionally an electrically powered brush or an air driven turbo brush, and any other type of accessory including a power tool such as a sander  1526  (see  FIG. 28 b   ). 
       FIG. 28 a    shows an exemplary power brush tool  1512  that may be connected to an upstream end  192  of wand  180 , or to an upstream end  200  of handle  160 . As shown, power brush tool  1512  includes a dirty air inlet  1514  and a downstream air outlet  1516 . Upstream end  192  or  200  of wand  180  or handle  160  may be connected to downstream air outlet  1516  in any suitable fashion. For example, power brush tool  1512  may include a tool lock  1518  for securing power brush  1512  to wand  180  or handle  160 . Tool lock  1518  may further include a release actuator  1520  (e.g. button, switch, or lever) that may be activated to allow power brush  1512  to be freely removed from wand  180  or handle  160 . 
     Power brush tool  1512  may include a brush drive (not shown) in a drive housing  1522 . The brush drive may be drivingly connected to a rotatably mounted brush  1524  for rotating brush  1524 . Brush  1524  may be positioned proximate dirty air inlet  1514  for making contact with a cleaning surface to dislodge dirt thereon and direct dirt into dirty air inlet  1514 . Power brush tool  1512  may include an electrical engagement member (not shown) for connection with wand  180  or handle  160  to receive electricity to power the brush drive. Alternatively, or in addition, power brush tool  1512  may include an alternative source of power, such as one or more batteries. 
       FIG. 28 b    shows an exemplary power sander tool  1526  that may be connected to an upstream end  192  of wand  180  or to an upstream end  200  of handle  160 . Like parts numbers refer to like parts in other figures. As shown, power sanding tool  1526  may include a belt drive in a drive housing  1522 . The belt drive may be drivingly connected to a rotatably mounted sanding belt  1528  for rotating belt  1528 . Belt  1528  may be positioned proximate dirty air inlet  1514  for sanding a working surface. Power sander tool  1526  may include an electrical engagement member (not shown) for connection with wand  180  or handle  160  to receive electricity to power the brush drive. Alternatively, or in addition, power sander tool  1526  may include an alternative source of power, such as one or more batteries. 
     Reference is now made to  FIGS. 34-38 , which show another example of a surface cleaning head that may be connected to upper portion  104 , to an upstream end  192  of wand  180  or to an upstream end  200  of handle  160 . In the example shown, surface cleaning head  1600  includes a lower surface  1604  having a dirty air inlet  116  in air flow communication with an up flow conduit  1608 . As shown, lower surface  1604  may include a forward portion  1608  and a rearward portion  1612 . Forward portion  1608  may be provided with dirty air inlet  116 . A cleaning member, that may be a discrete cleaning sheet  1614  may be mounted, and preferably removably mounted, preferably rearward of dirty air inlet  116 . 
     Cleaning sheet  1614  may be any cleaning sheet known in the art, such as an electrostatic cleaning sheet, and may be disposable or reuseable (e.g., washable). Cleaning sheet may be useable by itself or with a liquid applied to the floor. Cleaning sheet  1614  may be securable to cleaning head  1600  by any means known in the art, such as mechanical engagement members (e.g., hook and loop fasteners) an adhesive and the like. As exemplified, sheet  1614  and cleaning head  1600  may be provided with engagement members such as hook and loop fasteners (e.g., sheet  1614  may be provided with hook fasteners  1620  and the upper surface of sheet mounting portion  1624  of cleaning head  1600  may be provided with loop fasteners  1622  that are engageable with hook fasteners  1624  Alternately or in addition, sheet  1614  may be provided with tabs  1616  and  1618 , which may be securable to each other be, e.g., mechanical engagement members (e.g., such as by hook and loop fasteners). For example, tab  1616  may be provided with hook fasteners and tabs  1618  may be provided with loop fasteners engageable with the hook fasteners of tab  1616 . Tabs  1616  and  1618  may be wrapped around sheet mounting portion  1624  and secured together so as to secure, or assist in securing cleaning sheet  1614  to cleaning  1600 . 
     What has been described above has been intended to be illustrative of the invention and non-limiting and 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.