Abstract:
A hand vacuum cleaner is provided with a wand mounted to the dirty fluid inlet of the hand vacuum cleaner and the wand has a distal inlet that is mounted on a surface cleaning head. The hand vacuum cleaner has two cyclonic cleaning stages and a handle. In one embodiment, the handle has an upper end that is located that is located exterior to the second cyclonic stage and at a height intermediate the first and second spaced apart ends of the second cyclonic cleaning stage and a handle portion that extends upwardly when the hand vacuum cleaner is positioned on a horizontal surface. In another embodiment, the fluid flow motor and the handle are positioned rearward of the central axes of the first and second cyclonic cleaning stages.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     This application claims priority from U.S. patent application Ser. No. 11/953,292 which was filed on Dec. 10, 2007, which is allowed, and which claimed priority from U.S. Provisional applications 60/894,005 (filed on Mar. 9, 2007), 60/893,990 (filed on Mar. 9, 2007), and 60/869,586 (filed on Dec. 12, 2006), all of which are incorporated herein by reference in their entirety. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to surface cleaning apparatuses such as vacuum cleaners, wet/dry vacuum cleaner and carpet extractors. More particularly, the invention relates to surface cleaning apparatuses, which have a dirt bin having an off-centre inlet. 
     BACKGROUND 
     Surface cleaning apparatus have been developed which include one or more cyclonic cleaning stages. Each cleaning stage may include a single cyclone, or a plurality of cyclones positioned in parallel. Typically, in cleaning stages comprising a single cyclone, a dirt bin is positioned below the cyclone. The cyclone has an outlet, which is in fluid communication with an inlet of the dirt bin. Typically, the dirt bin and the cyclone are coaxial. The inlet to the dirt bin comprises an opening centrally positioned in an upper surface of the dirt bin. 
     For example, United States Patent Application Publication 2006/0130448 to Han et al. discloses a cyclone having a cubic dirt bin. The dirt bin is centrally positioned below the cyclone, such that the dirt bin and the cyclone are coaxial. A dirt inlet is positioned at the centre of the upper square surface of the dirt bin, aligned with a dirt outlet of the cyclone. 
     United States Patent Application Publication 2006/0123590 to Fester et al. discloses a surface cleaning apparatus having a first cleaning stage including a single cyclone, and a second cleaning stage including a plurality of cyclones in parallel. The cyclones of the second cleaning stage are arranged annularly around the cyclone of the first cleaning stage. The dirt bin of the first cleaning stage is coaxial with the cyclone of the first cleaning stage, and extends outwardly such that a portion is positioned underneath the cyclones of the second cleaning stage. The dirt inlet to the dirt bin is annular, and is centered about the longitudinal axis of the dirt bin. 
     SUMMARY 
     In one broad aspect, a surface cleaning apparatus is provided which has a collection chamber having an inlet that is off-centre from the centre of the collection chamber. 
     For example, the surface cleaning apparatus may comprise a fluid flow path extending from a dirt inlet to a clean fluid outlet, and a fluid flow motor positioned in the fluid flow path. A cyclonic cleaning stage is provided in the fluid flow path and comprises at least one, and preferably one, cyclone chamber. At least one dirt chamber is in fluid communication with the cyclone chamber and is positioned below the cyclone chamber. The dirt chamber has an upper portion proximate the cyclone chamber, a lower portion, a central axis extending vertically between the upper portion and the lower portion, and a dirt chamber inlet spaced from the central axis. The inlet is preferably provided in the top of the dirt chamber. 
     Embodiments in accordance with this broad aspect may be advantageous because the dirt chamber may have a larger cross sectional area than the cross sectional area of the cyclone chamber. Accordingly, the amount of dirt and/or water that may be collected in the dirt collection bin is increased. Further, the frequency with which the dirt chamber requires emptying is decreased. Further, by positioning the inlet off centre, the part of the dirt chamber distal to the inlet is more isolated from any fluid flow effects at the dirt inlet, thereby enhancing dirt retention in the dirt chamber. 
     In some embodiments, the upper portion of the dirt chamber has a width, and the dirt chamber inlet is spaced from the central axis by distance of at least 10% of the width. In further embodiments, the dirt chamber inlet is spaced from the central axis by distance of at least 15% of the width. In yet further embodiments, the dirt chamber inlet is spaced from the central axis by distance of at least 25% of the width. 
     In some embodiments, the cyclonic cleaning stage comprises a single cyclone having a dirt outlet positioned at the dirt chamber inlet, which is defined in an upper surface of the dirt chamber. 
     In some embodiments the surface cleaning apparatus comprises a generally transversely extending plate positioned adjacent the dirt chamber inlet. In further embodiments, the plate is positioned in the dirt chamber below the dirt chamber inlet. 
     In some embodiments, the upper portion has a perimeter, and the dirt chamber inlet is proximate the perimeter. 
     In some embodiments, the cyclone chamber has a longitudinal axis, and the central axis of the dirt chamber is spaced from the longitudinal axis. 
     In some embodiments, the dirt chamber is cylindrical. 
     In some embodiments, the dirt chamber comprises at least two sidewalls that meet at an angle. Such embodiments may be advantageous because the configuration of the sidewalls may prevent cyclonic motion in the dirt chamber. Accordingly, the amount of dirt in the dirt chamber, which becomes re-entrained in air may be reduced. 
     In some embodiments, the cyclonic cleaning stage has a maximum cross sectional area in a plane transverse to the a longitudinal axis of the cyclonic cleaning stage and the dirt chamber has a maximum cross sectional area in a plane transverse to the central axis that is larger than the maximum cross sectional area of the cyclonic cleaning stage. 
     In some embodiments, the maximum cross sectional area of the dirt chamber is at least 50% larger than the maximum cross sectional area of the cyclonic cleaning stage. 
     In another broad aspect, a surface cleaning apparatus is provided. The surface cleaning apparatus comprises a fluid flow path extending from a dirt inlet to a clean fluid outlet, and a fluid flow motor positioned in the fluid flow path. The surface cleaning apparatus further comprises a first cyclonic cleaning stage comprising a cyclone chamber. A dirt chamber is in fluid communication with the cyclone chamber and positioned below the cyclone chamber. The dirt chamber has a dirt chamber inlet that is off-centre. 
     In some embodiments, the dirt chamber has an upper portion proximate the cyclone chamber, a lower portion, and a central axis extending vertically between the upper portion and the lower portion, and the dirt chamber inlet is spaced from the central axis. 
     In some embodiments, the dirt chamber has a width, and the dirt chamber inlet is off-centre by a distance of at least 10% of the width. In further embodiments, the dirt chamber inlet is off-centre by a distance of at least 15% of the width. In yet further embodiments, the dirt chamber inlet is off-centre by a distance of at least 25% of the width. 
     In some embodiments, the surface cleaning apparatus further comprises a generally transversely extending plate positioned adjacent the dirt chamber inlet. 
     In some embodiments, a plate is provided in a flow path from the cyclone chamber to the dirt chamber. In further embodiments, the plate is provided in the dirt chamber. 
     In some embodiments, the dirt chamber inlet comprises a dirt outlet of the cyclone chamber. 
     In some embodiments, the upper portion defines a perimeter, and the dirt chamber inlet is proximate the perimeter. 
     In some embodiments, the surface cleaning apparatus further comprises a second cyclonic cleaning stage downstream from the cyclone. In some such embodiments, the second cyclonic cleaning stage comprises a plurality of cyclone in parallel. In some further embodiments, the first cyclonic cleaning stage comprises a single cyclone. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other advantages of the present invention will be more fully and particularly understood in connection with the following description of the preferred embodiments of the invention in which: 
         FIG. 1A  is a perspective illustration of an embodiment of a surface cleaning apparatus of the present invention; 
         FIG. 1B  is a perspective illustration of another embodiment of a surface cleaning apparatus of the present invention; 
         FIG. 1C  is a perspective illustration of another embodiment of a surface cleaning apparatus of the present invention; 
         FIG. 1D  is a perspective illustration of another embodiment of a surface cleaning apparatus of the present invention; 
         FIG. 2A  is a cross-sectional view of the embodiment of  FIG. 1A , taken along line  2 A- 2 A; 
         FIG. 2B  is a cross sectional view of the embodiment of  FIG. 1B , taken along line  2 B- 2 B; 
         FIG. 2C  is a cross sectional view of the embodiment of  FIG. 1C , taken along line  2 C- 2 C; 
         FIG. 2D  is an exploded view of the embodiment of  FIG. 1D ; 
         FIGS. 3A to 5A  are top views of various embodiments of a dirt chamber of the present invention; 
         FIGS. 3B to 5B  are side views of the embodiments of  FIGS. 3A to 5A ; 
         FIGS. 3C-5C  are perspective views of the embodiments of  FIGS. 3A to 5A ; 
         FIG. 6  is a perspective view of the surface cleaning apparatus of  FIG. 1A , showing a panel in an opened position; and, 
         FIG. 7  is a perspective view of the surface cleaning apparatus of  FIG. 2A , showing a panel in an opened position. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Embodiments of a surface cleaning apparatus  110  of the present invention are shown in  FIGS. 1A-1D . As shown in  FIGS. 1A and 1C , the surface cleaning apparatus  110  may be a hand vacuum cleaner, which may be converted to a shoulder strap vacuum cleaner by the addition of a shoulder strap (not shown). Alternatively, as shown in  FIGS. 1B and 1D , the surface cleaning apparatus  110  may be a shop-vac or wet/dry type vacuum cleaner. In other embodiments, the surface cleaning apparatus  110  may be another type of surface cleaning apparatus, for example an upright vacuum cleaner, a canister type vacuum cleaner, a stick vacuum cleaner, a back pack vacuum cleaner, a carpet extractor or the like. 
     The surface cleaning apparatus  110  comprises a dirty fluid inlet  112 , a clean fluid outlet  114 , and a fluid flow path extending therebetween. At least one cyclonic cleaning stage  116  is provided in the fluid flow path. A fluid flow motor  118  is positioned in the fluid flow path for drawing a fluid (e.g. air or water) from the dirty fluid inlet  112  to the clean fluid outlet  114 . The surface cleaning apparatus may draw in water and/or air that may have entrained therein dirt through inlet  112  and discharge air through outlet  114 . The water and/or dirt will accumulate in dirt chamber  144 . 
     Referring to  FIGS. 2A to 2D , dirty fluid entering dirty fluid inlet  112  is directed to cyclonic cleaning stage  116 . As is known in the art, a hose or wand having a distal inlet that may be mounted on a surface cleaning head may be attached to inlet  112 . In the embodiments shown, cyclonic cleaning stage  116  comprises a single cyclone chamber  120  extending longitudinally along a first longitudinal axis  122 . In other embodiments, cyclonic cleaning stage  116  may comprise a plurality of cyclones. Cyclone chamber  120  comprises a clean air outlet  124 , and a dirt and/or water outlet  126 . A dirt chamber  144 , as will be described further hereinbelow, is positioned below dirt outlet  126 . It will be appreciated that other cleaning or treatment stages may be provided upstream of the cyclone inlet. 
     In some embodiments, air exiting cyclone chamber  120  may be directed past motor  118 , and out of clean fluid outlet  114 . Alternatively, air exiting cyclone chamber  120  may be directed to one or more additional cleaning stages, such as another component, for example housing a filter prior to flowing to motor  118 . The second cleaning  128  stage comprises a plurality of second cyclones  130  in parallel. 
     The second cleaning stage  128  has, in the examples illustrated, a generally cylindrical configuration with a second longitudinal axis  132 . In the embodiments of  FIGS. 2A ,  2 B, and  2 D, the second axis  132  is parallel to, and laterally offset from, first axis  122 . In the embodiment of  FIG. 2C , the second axis  132  is parallel to and aligned with first axis  122 . In the embodiments shown in  FIGS. 2A and 2B , each of the second cyclones  130  in the assembly receives air from the clean air outlet  124  of the first cyclone, and discharges air through outlets  134  into a manifold  136 . Air is evacuated from the manifold  136  through a conduit  138  disposed centrally of the assembly. From the conduit  138  the air is drawn towards the motor  118 , and expelled from the apparatus  110  through the exhaust  114 . In the embodiment of  FIG. 2C , each of the second cyclones  130  receives air from the clean air outlet  124  of the first cyclone via a conduit  137 , and discharges air via outlets  134  into a manifold  139 . From manifold  139 , the air is drawn through a filter  141 , and past motor  118 . In the embodiment of  FIG. 2D , each of the second cyclones  130  receives air from the clean air outlet  124  of the first cyclone via a conduits  127 , and discharges air via outlets  134  into a motor housing  142 . Alternately or in addition, in some embodiments the additional cleaning stage  128  may include a filter element, such as a pre-motor foam membrane, disposed in the fluid stream between the cleaning stage  128  and the motor  118 . 
     In the embodiments shown in  FIGS. 2A-2C , motor  118  is disposed laterally adjacent the additional cleaning stage  128 , in a motor housing  142 . In the embodiment of  FIG. 2D , motor  118  is disposed laterally adjacent the first cleaning stage above the additional cleaning stage, namely filters  141  and second cyclonic cleaning stage  128 . In the embodiment of  FIG. 2A , motor  118  extends transverse to first longitudinal axis  122 . In the embodiment of  FIGS. 2B-2D , motor  118  extends parallel to first longitudinal axis  122 . The motor  118  is, in the examples illustrated, offset from the second cleaning stage  128 , having a portion that abuts or is adjacent at least a portion of the dirt chamber. It will also be appreciated that motor housing may be adjacent both the first and second housings and, thereby defining a generally triangular configuration in top plan view. Motor  118  may alternately be positioned at any other location known in the surface cleaning arts, such as above or below the cyclonic cleaning stage. 
     As previously mentioned, cyclone chamber  120  is in fluid communication with a dirt chamber  144 , which is positioned below the dirt outlet  126 . Dirt chamber  144  serves to collect dirt that is removed, e.g., from the air passing through cyclone chamber  120  or water drawn in through inlet  112 . Dirt chamber  144  may be of any configuration known in the art provided the dirt chamber inlet  150  is off centre. As exemplified, dirt chamber  144  comprises an upper portion  146 , which is proximate cyclone chamber  120 , and a lower portion  148 . Dirt chamber  144  is bounded by at least one wall. In the embodiments shown, dirt chamber  144  is bounded by a top wall  152  a bottom wall  154 , and at least one sidewall  156 . 
     Dirt chamber  144  further comprises a dirt chamber inlet  150 , which is preferably defined in upper portion  146 , and more preferably defined in top wall  152 . Dirt chamber inlet  150  is in fluid communication with dirt outlet  126  of cyclone chamber  120 . In some embodiments, as shown, dirt chamber inlet  150  and dirt outlet  126  may coincide. In other embodiments, dirt chamber inlet  150  and dirt outlet  126  may be separate, and may have a channel or passage providing fluid communication therebetween (not shown). 
     Dirt chamber inlet  150  may be of a variety of shapes and sizes. In the preferred embodiment, dirt chamber inlet  150  has a circular outer perimeter  162 . In further embodiments, wherein surface cleaning apparatus  110  comprises a divider plate, as will be described further hereinbelow, dirt chamber inlet  150  may be substantially annular. 
     Dirt chamber  144  may be of a variety of shapes and sizes. For example, in the embodiment of  FIGS. 1A ,  2 A, and  5 A- 5 C, dirt chamber  144  comprises two substantially rounded lobes having curved sidewalls  156 . In the embodiment of  FIGS. 1B ,  2 B,  1 C and  2 C, dirt chamber  144  comprises two lobes which comprise substantially straight sidewalls  156 . In the embodiment of  FIGS. 1D ,  2 D, and  3 A- 3 C, dirt chamber  144  comprises a single rectangular chamber. In the embodiment of  FIGS. 4A-4C , dirt chamber  144  comprises a single trapezoidal chamber. 
     In some embodiments shown, dirt chamber  144  comprises at least two sidewalls which meet at an angle. For example, in the embodiment of  FIGS. 2B-2D , sidewalls  156   a  and  156   b  meet at a corner  157 . Such embodiments may be advantageous because cyclonic action in the dirt chamber may be minimized or reduced by providing the dirt chamber with sidewalls, which meet at an angle. Accordingly, dirt in the dirt chamber may be prevented from being re-entrained the circulating air. In other embodiments, dirt chamber  144  may be of another shape. For example dirt chamber  144  may be cylindrical. 
     In the embodiments shown, dirt chamber  144  extends laterally beyond the cyclone chamber  120 . That is, if cyclonic cleaning stage  116  has a maximum cross sectional area in a plane transverse to axis  122  (e.g. parallel to bottom wall  154 ), and dirt chamber  144  has a maximum cross sectional area in a plane transverse to axis  122  (e.g. parallel to bottom wall  154 ), the maximum cross sectional area of dirt chamber  144  is greater than the maximum cross sectional area of cyclonic cleaning stage  116 . In some particular embodiments, the maximum cross sectional area of dirt chamber  144  is at least 25% larger, more preferably at least 50% larger and most preferably at least 75% larger than the maximum cross sectional area of cyclonic cleaning stage  116 . Such embodiments may be advantageous because the overall volume of the dirt chamber may be increased without increasing the footprint of surface cleaning apparatus  110 . In the embodiment of  FIGS. 1A ,  1 C and  1 D, dirt chamber  128  extends laterally such that a portion thereof is positioned beneath second cleaning stage  128 . In the embodiment of  FIG. 2A , dirt chamber  128  extends laterally such that a portion thereof is positioned beneath second cleaning stage  128 , and motor  118 . 
     It will be appreciated that in an alternate embodiment, dirt chamber  144  may have a cross sectional area in a plane transverse to axis  122  that is essentially the same as the cross sectional area of the cyclone  116  in a plane transverse to axis  122 . This may be achieved by placing inlet  150  below inlet  126  but at adjacent sidewall  156 . Thus the inlet  150  is off centre and dirt chamber  144  may be underneath only a portion of cyclone  116 . 
     Referring to  FIGS. 3A-3C , in some embodiments, dirt chamber  128  comprises a central axis  158  extending between upper portion  146 , and lower portion  148 . When surface cleaning apparatus  110  is positioned such that axis  122  extends vertically, central axis  158  may extend vertically between top wall  152  and bottom wall  154 . Central axis  158  is positioned such that it extends through a centroid  160  of top wall  152 . As used herein, the centroid of top wall  152  is defined as the point located centrally in the area A defined by dirt chamber  144  when viewed from above. For example, in the embodiment of  FIGS. 3A-3C  dirt chamber  144  is rectangular. When viewed from above, dirt chamber  130  has a Length L 1  and a width W 1 , and centroid  160  is positioned at a point corresponding to ½ L 1  and ½ W 1 . In another example, as shown in  FIGS. 4A-4C , dirt chamber is substantially trapezoidal when viewed from the front. Accordingly, top wall  152  of dirt chamber  144  has a length L 2 , bottom wall  154  of dirt chamber  144  has a length L 3 , and dirt chamber  144  has a width W 2 . When viewed from above, area A is defined by L 3  and W 2 . Therefore, in this embodiment, centroid  160  is positioned at a point corresponding to ½ L 3  and ½ W 2 . In another example, as shown in  FIGS. 5A-5C , dirt chamber has two elongate and rounded lobes. When viewed from above, dirt chamber  144  has an overall width W 3 , and an overall length L 4 . The centroid  160  is positioned at a point corresponding to ½ W 3  and ½ L 4 . 
     Dirt chamber inlet  150  is off centre with respect to dirt chamber  144 . That is, dirt chamber inlet  150  is spaced from central axis. In further embodiments, central axis  158  is spaced from longitudinal axis  122 . Such embodiments may allow for the volume of dirt chamber  144  to be increased, without substantially increasing the footprint of surface cleaning apparatus  110 . 
     Referring to  FIGS. 3A-5C , dirt chamber inlet  150  may be spaced from central axis  158  by a distance X, which is defined as the shortest distance between a perimeter  162  of dirt inlet  150 , and central axis  158 . Distance X may vary depending on a variety of factors. Dirt chamber inlet  150  may be spaced from the central axis by a distance of at least 10% of the maximum length, L max . In a preferred embodiment, dirt chamber inlet  150  is spaced from central axis  158  by a distance of at least 15% of L max . In a more preferred embodiment, dirt chamber inlet  150  is spaced from central axis  158  by a distance of at least 25% of L max . 
     In some particular embodiments, as shown in  FIGS. 5A-5C , the upper portion  146  of dirt chamber  144  has a perimeter  164 , and dirt chamber inlet  150  is adjacent the perimeter. 
     Referring to  FIGS. 6 and 7 , the dirt chamber  144  preferably has an openable panel  166  to facilitate emptying debris collected therein. In the embodiment of  FIG. 6 , panel  166  comprises bottom wall  15 , which is movable between open and closed positions. The bottom wall is preferably pivotally mounted to at least one sidewall  156 . In the embodiment of  FIG. 7 , panel  166  comprises top wall  152  of dirt chamber  132 . In this embodiment, when panel  166  is opened, cyclonic cleaning stage  116 , motor  118 , and second cleaning stage  128  pivot together with panel  166 . In other embodiments, dirt collection chamber  144  may be emptyable by any means known in the vacuum cleaner art. For example, dirt collection chamber  144  may be removably mounted to the surface cleaning apparatus or otherwise openable. 
     The apparatus  110  may also include a divider plate  168  positioned adjacent the dirt outlet  126  of the first cyclone chamber  120 . In the example illustrated in  FIGS. 2A-2C , the divider plate  168  is positioned within the dirt chamber  144 , adjacent to but spaced below the dirt outlet  126 . In other embodiments, divider palate  168  may be positioned within dirt outlet  126 . In such an embodiment, dirt chamber inlet  150  may be defined between top wall  152  and divider plate  168 , and may be substantially annular. The divider plate  168  may generally comprises a disc  170  that, when positioned below the dirt outlet  126 , has a diameter slightly greater than the diameter of the dirt outlet  126 , and disposed in facing relation to the dirt outlet  126 . The disc  170  is, in the example illustrated, supported by a pedestal  172 . In the embodiment of  FIGS. 2A and 2C , pedestal  172  extends upwardly from bottom wall  154  of the dirt chamber  144 . In the embodiment of  FIG. 2B  pedestal  172  extends downwardly from top wall  152  of dirt chamber  144 . Alternately, plate  168  may be mounted to a sidewall  156  of the dirt collection chamber  144 . 
     In the embodiment of  FIGS. 1A and 10 , the surface cleaning apparatus may be carried by a strap (not shown) or by using handle  174 . In the embodiments of  FIGS. 1B and 1D , the surface cleaning apparatus comprises one or more wheels  176 , glides, or the like, for moving surface cleaning apparatus  110  along a surface. 
     In some embodiments, dirt chamber  144  preferably forms a portion of a casing member  177  for the apparatus  110  that is of a unitary, integral construction. For example, casing member  177  may comprise dirt chamber  144 , the outer wall of cyclone chamber  120 , a housing for the second cleaning stage  128 , motor housing  142 , and handle  174 . 
     In some embodiments, dirt chamber  144  may comprise one or more liner bags  180 , for example as shown in  FIG. 2B , for lining dirt chamber  144  and aiding in emptying dirt chamber  144 . 
     It will be appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments or separate aspects, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment or aspect, may also be provided separately or in any suitable sub-combination. 
     Although the invention has been described in conjunction with specific embodiments thereof, if is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention.