Patent Publication Number: US-2006000040-A1

Title: Surface cleaning apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This application is a continuation-in-part of application Ser. No. 10/431,783, filed May 8, 2003. This application also claims priority to the subject matter of U.S. Provisional Application No. 60/564,296, filed Apr. 22, 2004. 
    
    
     FIELD OF THE INVENTION  
      This invention relates to a surface cleaning apparatus, such as for a floor or upholstery.  
     BACKGROUND OF THE INVENTION  
      Conventional surface cleaning apparatus which do not use suction, such as sweeper type floor cleaning apparatus using rotatable brushes to pick up and collect particles and other debris, typically have a leading front face of the body of the sweeper apparatus with a substantially planar lower edge. During use, such a conventional sweeper requires a clearance distance to be maintained between the lower edge of the body of the sweeper apparatus and the surface to be cleaned.  
      If the clearance distance between the lower edge of the sweeper apparatus and the surface to be cleaned is too small, debris will accumulate in front of the lower edge of the front face of the sweeper apparatus and will be prevented from passing under the lower edge and being swept up by the bristles of brushes within the body of the apparatus. At present, to remove a piece of debris larger than the clearance between the lower edge and the surface to be cleaned, it is necessary either to pick up the debris by hand or to raise the body of the sweeper apparatus away from the surface to be cleaned and replace it over the larger debris. On the other hand, if the clearance distance between the lower edge of the sweeper apparatus and the surface to be cleaned is too great, turbulence caused by the rotation of the bristles can cause debris to be pushed along in front of the sweeper apparatus as the sweeper apparatus is pushed forward. As the clearance between the lower edge of the body of the sweeper and the surface to be cleaned is increased, the efficiency of the sweeper apparatus in picking up and collecting debris is reduced.  
      What is needed is a surface cleaning apparatus and cleaning method which is adapted to be able to efficiently pick up debris of varying sizes without the need to remove the surface cleaning apparatus from the surface to be cleaned.  
     SUMMARY OF THE INVENTION  
      It is therefore an object of the present invention to provide a surface cleaning apparatus which overcomes, or at least ameliorates, at least some of the problems of known apparatus.  
      In an embodiment, the invention provides a surface cleaning apparatus comprising a body having a forward compartment and a rear compartment, an elongate rotatable brush extending across the forward compartment, and a belt connecting an electric motor to the rotatable brush. The body includes a front face having a non-planar lower edge such that the distance between the lower edge and a plane of a surface to be cleaned is not uniform. The non-planar lower edge may be provided as a recess or notch in the front face. In an embodiment, the lower edge of the front face includes at least one recess or notch.  
      In another embodiment, the front wall of the surface cleaning apparatus has a lip of increased thickness relative to the thickness of the rest of the front wall. The lip is also at a higher elevation than the bottom surface of the body.  
      In still other embodiments, the surface cleaning apparatus includes an intermediate compartment defined by walls between the forward and intermediate compartment, between the rear and intermediate compartment, and the side walls of the body. The wall between the forward and intermediate compartment can be inclined rearwardly. The wall between the rear and intermediate compartments can serve to seal the rear compartment from the intermediate compartment. The intermediate compartment can be in the form of a removable tray, or the intermediate compartment can be emptied by removing a sidewall.  
      In an embodiment, the surface cleaning apparatus can also include an auxiliary brush. The auxiliary brush can extend from the forward compartment and can be connected to the same motor that drives the elongate brush. The auxiliary brush can also be inclined at an angle relative to the plane of the body of the surface cleaning apparatus.  
      In yet other embodiments, the front portion of the surface cleaning apparatus can be chamfered to increase the extent to which the bristles of the elongate brush protrude from the body. Additionally, a front part of the forward compartment can be removable to increase the extent that the bristles protrude from the surface cleaning apparatus.  
      The invention also provides a method for cleaning a surface, such as a surface with large particles of dust or dirt. In an embodiment, a surface cleaning apparatus having a body, one or more compartments, and a front wall is provided, the front wall having a bottom surface with a lip as well as a notch or opening in the bottom surface. The body is then tilted forward so that the bottom surface lip contacts a surface to be cleaned. One or more particles on the surface to be cleaned are then admitted into the surface cleaning apparatus through the recess or notch. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      For a better understanding of the present invention and to show more clearly how it may be carried into effect reference will now be made, by way of example, to the accompanying drawings in which:  
       FIG. 1  is a plan view of one embodiment of a surface cleaning apparatus according to the present invention;  
       FIG. 2  is a side elevational view, partly in section, of the surface cleaning apparatus shown in  FIG. 1 ;  
       FIG. 3  is an perspective view of a front face of the surface cleaning apparatus of  FIGS. 1 and 2 ;  
       FIG. 4  is an elevational view of the surface cleaning apparatus of FIGS.  1  to  3  with an alternative handle;  
       FIG. 5  is a perspective view of another embodiment of a surface cleaning apparatus according to the present invention with a front face removed for clarity;  
       FIG. 6  is a perspective view of the apparatus of  FIG. 5 , with the front face of the housing thereof removed;  
       FIG. 7  is an underside view of the apparatus of  FIG. 5  with the front face removed for clarity;  
       FIG. 8  is perspective view of another embodiment of a surface cleaning apparatus according to the invention.  
       FIG. 9  is an underside view of the apparatus of  FIG. 8 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      In an embodiment corresponding to the surface cleaning apparatus shown in FIGS.  1  to  3 , the surface cleaning apparatus comprises a body  1 , suitably moulded of plastics material, and having at least two compartments and preferably at least three compartments.  
      A rear compartment  3  houses an electric motor  5  and a rechargeable battery pack  7 . The battery pack  7  may be connected to a mains power supply (not shown) for recharging the battery pack. The battery pack may either be connected to the mains supply whenever the apparatus is not in use or at suitable times when the battery pack has become depleted. Switch means (not shown) is provided to permit a user to energise and de-energise the motor  5  as desired. As an alternative to a rechargeable battery pack, the apparatus could employ disposable batteries or be mains powered, such as being adapted to operate by plugging into household electric current.  
      A forward compartment  9  houses an elongate rotatable brush arrangement  11 . The brush arrangement  11  is rotated in a direction denoted by arrow  19 , such that an upper surface of the brush arrangement is rotated away from the rear compartment  3 . For convenience a forward wall  201  of the forward compartment  9  is arcuate and extends around the periphery of the brush arrangement  11 . The bottom of the forward compartment is open at  13  to allow the bristles of the brush arrangement to contact a floor, carpet or the like over which the surface cleaning apparatus is to be moved.  
      In an embodiment, the forward wall  201  of the forward compartment is also the front wall  201  of the surface cleaning apparatus. The lower edge  203  of the front wall  201  is non-planar, as shown in  FIG. 3 . The lower edge  203  incorporates a recess  205  with a width in a range from about 20 mm to about 150 mm, preferably about 60 mm. The depth of the recess, that is the distance between the top  207  of the recess  205  and the lowest portion  209  of the lower edge  203  is nominally about 10 mm but may, for example, be in the range from about 4 mm to about 20 mm. The recess allows debris, such as dust, dirt and the like, too large to pass under the lowest portion  209  of the lower edge  203  to pass into the forward compartment and be picked up by means of the brush arrangement  11 . Turbulence caused by the rotation of the brush assembly, which could cause relatively small debris to be pushed along in front of the surface cleaning apparatus, is minimized as the majority of the lower edge is maintained in sufficiently close proximity to the surface to be cleaned. The distance between the surface to be cleaned and the lowest portion  209  of the lower edge  203  is nominally about 10 mm but may, for example, be in the range from about 4 mm to about 20 mm.  
      In another embodiment, the bottom surface of the front wall is elevated relative to the bottom surface of the body to create space for admitting particles into the forward compartment during the operation of the surface cleaning apparatus. For example, in the embodiment shown in  FIG. 8 , bottom surface  203  of the front wall  201  is higher in elevation than the bottom of body  1 . Front wall  201  also includes a notch or opening  205 . The notch or opening  205  increases the distance between the bottom surface  203  of the front wall and the surface being cleaned in the region of the notch. This allows larger particles be admitted through the notch and into the compartments of the surface cleaning apparatus. The notch  205  can be located anywhere on the front wall. Conveniently, the notch or opening can be located in the center of the front wall, as this allows a user to easily align the notch with a particle to be swept. Bottom surface  203  of front wall  201  further comprises a lip  92  which has an increased thickness relative to the front wall  201 . If the surface cleaning apparatus is tipped forward so that the bottom surface of the front wall comes into contact with a surface being cleaned, lip  92  reduces the likelihood that the bottom surface of the front wall will “dig in” to the surface. Instead, the thicker lip will more evenly distribute weight, making it easier to move the surface cleaning apparatus while being tipped forward.  
      The height of the notch or opening should be sufficient to allow particles to be taken into the intermediate compartment while the body is being tipped forward. In an embodiment, the height of the opening relative to the bottom surface of the front wall is the same as the distance from the bottom surface of the front wall to the bottom of the surface cleaning apparatus body. For example, if the bottom surface of the front wall is higher in elevation than the surface to be swept by 1 cm (when the body is not tipped forward), the elevation of the bottom surface in the notch relative to the bottom surface of the rest of the front wall would also be 1 cm. This would lead to a total elevation for the bottom surface of the opening of 2 cm relative to a surface to be cleaned.  
      The width of the notch or opening can be of any convenient size, as long as the width is small enough to prevent undue stress on the front wall when the body is tipped forward to bring the bristles into closer contact with a surface. Thus, the notch or opening can have various widths, as the width of the front wall could range from as small as 4 inches to as large as 20 inches. Other common widths for the front wall include 8 inches, 10 inches, 11.5 inches, 13 inches, 14 inches, and 15 inches. In an embodiment, the width of the opening is at least 10% of the width of the front wall and preferably at least 15%. In an embodiment, the width of the opening is 33% or less of the width of the front wall and preferably 25% or less.  FIGS. 3, 8 , and  9  show examples of a notch or opening  205  in a front wall  201 .  
      The rear of the forward compartment is a rearwardly inclined wall  15  which allows debris to be propelled up the wall due to rotation of the brush arrangement  11  and to pass over the wall into an intermediate compartment  17  which will be described in more detail hereinafter. The wall  15  extends upwardly to about the same height as the top of the brush arrangement  11  and is angled rearwardly (i.e. away from the forward compartment) at an angle of about 18 degrees. The precise angle is not important, but the inclination facilitates the passage of the debris up and over the wall and at the same time facilitates retention of the debris within the intermediate compartment  17 . The brush arrangement extends substantially the entire width of the forward compartment and is provided with two helically arranged rows of bristles. The two rows are diametrically opposed and each row is in the form of a pair of separate helices which twist in opposite directions and meet substantially midway between the ends of the brush arrangement.  
      The intermediate compartment  17  is positioned between the wall  15  and a wall  21  which encloses the electrical components  5 ,  7  in the rear compartment  3 , the wall  21  protecting the components in the rear compartment from the ingress of debris. The intermediate compartment  17  also has a lower wall, an upper wall and side walls formed by the outer wall of the body  1 . Debris therefore accumulates within the intermediate compartment  17 . The intermediate compartment is provided with a removable closure to facilitate the removal of debris. For example, one of the walls, such as a side wall, the upper wall or the lower wall, can be removed in order that the debris can be emptied from the intermediate compartment, the removed wall being replaced once the compartment has been emptied. The removable wall may comprise a clear section to enable a user to determine when the intermediate compartment requires emptying. Ideally, side wall  23  is removable for emptying purposes. The wall  15  provides the advantage that debris does not readily escape from the intermediate compartment  17  and, even if the body of the surface cleaning apparatus is inclined such that the forward compartment is below the intermediate compartment, the debris does not escape from the intermediate compartment. Alternatively, the intermediate compartment can comprise a removable tray. In such an embodiment, the side wall  23  can form a part of the removable tray.  
      In an embodiment, the brush arrangement  11  is rotated by the motor  5  by way of toothed rollers  25 ,  27  attached to the motor and to the brush, respectively, and by way of a toothed belt  29 , for example of elastomeric material, extending around the two rollers. The toothed belt  29  is enclosed within a tunnel  31  where it passes through the intermediate compartment  17  in order to prevent the ingress of debris into the rear compartment  3 . The tunnel  31  may pass through the intermediate compartment  17  at any convenient point. However, particularly in the event side wall  23  is removable for emptying purposes, the tunnel may be arranged at that side of the intermediate compartment  17  remote from the side wall  23 .  
      In an embodiment, a handle  33  is attached to the body  1  in the region of the rear compartment  3 , the body being formed with a recess  35  beneath the handle to allow the handle to be gripped while maintaining a low profile for the surface cleaning apparatus. The handle  33  may be in two parts, a first part  37  which is secured to the body  1  and a second part  39  which can be removed from the first part and replaced by a longer handle part  41  as shown in  FIG. 4 . The longer handle part  41  is provided with swivel means  43  to allow the handle part  41  to rotate about the axis thereof relative to the body  1  and with pivot means  45  to allow the handle part to pivot about an axis transverse to the axial direction of the handle part to enable the surface cleaning apparatus to be steered by the user. As an alternative to interchangeable handles, the handle part  41  may be removably engageable with the handle part  33 . In such a case, the handle part  33  is arranged such that the swivel means  43  functions only in certain positions of the handle part  33  in order that movement can be inhibited when the handle part  33  is used alone.  
      In some embodiments, the bristles of the brush arrangement  11  can extend outwardly from the aperture in the lower face of the forward compartment  9 , as shown for example in  FIG. 4 . In order to remove stubborn debris and/or to revitalise carpet, the lower edge of the front wall of the forward compartment may be chamfered, or the front wall may be movable (including removable), to increase the exposure of the bristles in this region. In this way, the forward part of the apparatus may be inclined relative to the surface to be cleaned, thereby increasing contact between the bristles and a surface to be cleaned and, on some surfaces, increasing the depth to which the bristles penetrate and clean the surface.  
       FIG. 8  shows the profile of a forward compartment according to another embodiment of the invention. In this embodiment, bottom surface  203  of the front wall  201  of the forward compartment is chamfered and at a higher elevation relative to the surface being swept than the bottom surface of the body. The higher elevation of bottom surface  203  is achieved by having the side wall of the forward compartment rise at an angle away from the surface to swept. In an embodiment, this angle is at least 5 degrees and preferably at least 10 degrees. In an embodiment, this angle is 20 degrees or less, preferably 15 degrees or less. Additionally, the bottom surface  203  of the faceplate is also angled away from the surface to be cleaned. The angle of the bottom surface relative to the surface to be cleaned can be any convenient angle, such as the same angle as the rise angle of the sidewall of the forward compartment relative to the surface being swept. In an embodiment, this angle is at least 5 degrees and preferably at least 10 degrees. In an embodiment, this angle is 20 degrees or less, preferably 15 degrees or less. In another embodiment, the front wall  201  may be movable (including removable) to increase the exposure of bristles to a surface to be cleaned.  
      An auxiliary rotary brush  11  may also be provided at the side of the brush arrangement  11  which incorporates the roller  27  and the belt  29 . Such an auxiliary brush is described, for example, in GB-A-1 547 286. Such an auxiliary brush is able to sweep debris into the path of the brush arrangement  11  which might otherwise be missed due to the lack of bristles in the region of the roller  27 . The auxiliary brush may be driven by any suitable means, such as gearing from the brush arrangement  11  or by friction with the surface to be swept, and is suspended from and extends outwardly beyond the body  1 . The auxiliary brush may comprise a cylindrical body rotatable about an axis which is inclined to the vertical by about 10 degrees so as to extend outwardly beyond the body  1 . Bristles protrude radially outwardly from the periphery of the cylindrical body, but need not be perpendicular to the axis of rotation and may preferably be at an angle of about 80 degrees to the axis of rotation so as to form a cone which increases in cross-section with increasing distance from the body  1 .  
      In another embodiment, the front wall  201  of the forward compartment  9  may be removed to expose the bristles at the front of the apparatus. This effectively increases the aperture in the forward compartment which would seriously impair the effectiveness of a suction cleaner, but in the present invention can effectively be used to assist in the sweeping of stairs, cleaning upholstery and carpets in vehicles and the like operations where a greater exposed area of bristles can be useful. As an alternative to removing the front wall of the compartment  9 , the front wall may be movable, for example pivotable or slidable, relative to the remainder of the compartment in order to expose the bristles.  
      Although not shown, the rear compartment  3  may be provided with ground-engaging wheels in order to assist mobility of the surface cleaning apparatus. The ground-engaging wheels may, for example, be formed externally in the side regions of the rear compartment  3  or may be provided within recesses formed at least partly beneath the rear compartment  3 .  
      Although the illustrated embodiments of the present invention are intended primarily for domestic use, the surface cleaning apparatus can also be used outdoors or in workshops if desired. However, it may be preferable to provide a more rugged design specifically adapted for such use.  
      In use of the surface cleaning apparatus according to various embodiments of the invention, the apparatus is placed upon a surface to be swept, such as a carpet, and the switch is operated to energise the motor. This rotates the brush arrangement to allow intake (sweeping) of debris from the surface and then propels the debris up and over an inclined wall and into an intermediate compartment where it is temporarily stored. As the surface cleaning apparatus is moved over the surface with the brush arrangement rotating, any further debris is similarly swept from the surface and propelled up and over the inclined wall and into the intermediate compartment. If there is a piece of relatively larger debris, the surface cleaning apparatus can be steered such that the recess in the front wall of the apparatus is passed over the larger debris and the debris is picked up by the rotating brush arrangement.  
      In another embodiment, the surface cleaning apparatus can be tilted forward to bring the bristles into closer contact with the floor. For example, the apparatus could be tilted forward on a soft carpet surface in order to bring the rotating brush into greater contact with the surface being swept. In this situation, the lip of the bottom surface of the front wall can come into contact with the surface being swept, reducing the clearance between the bottom surface of the front wall and the surface being swept. This increases the contact between the brush and the surface being swept. Additionally, because of the notch in the front wall, the risk that particles may be pushed out of the way rather than being collected by the surface cleaning apparatus is greatly reduced. The notch or opening increases the distance between the bottom surface of the front wall and the surface being cleaned in the region of the notch. When the body is tilted forward, the notch facilitates intake of debris. By admitting a piece of debris through the notch, the piece of debris can be readily swept into the intermediate compartment. The notch can be located anywhere on the front wall. Conveniently, the notch or opening can be located in the center of the front wall, as this allows a user to easily align the notch with a particle to be swept.  
      The surface cleaning apparatus is extremely portable and can be employed wherever it may be required. For example, it can be used to sweep stairs without the need for electrical leads or suction hoses. The shape of the apparatus with the rounded shape of the rear compartment as illustrated facilitates movement of the apparatus over stairs, but ground engaging wheels may be provided to further facilitate such sweeping operations.  
      When the intermediate compartment is to be emptied, one wall of the compartment is removed as explained above and the debris can readily be discharged. The removable wall is then replaced. Alternatively, the intermediate compartment may be in the form of a tray which can be removed and emptied so as to discharge debris. The tray may comprise a section which is clear to enable a user to determine when the intermediate compartment requires emptying.  
      When the surface cleaning apparatus is not in use it can be stored, for example either in a cupboard or the like or plugged into a mains supply in order to recharge the battery  7 .  
      In various embodiments, the surface cleaning apparatus according to the invention incorporates an electrically driven brush arrangement. The brush arrangement is not driven by frictional forces between the surface cleaning apparatus and the surface over which it is to be moved. Thus, efficiency of the apparatus is not dependent on the nature of the frictional contact. Further, the apparatus does not rely on suction means to draw the debris into a storage chamber. Thus, efficiency of the apparatus is not dependent on the effectiveness of suction means and the substantial power drain of suction means on the rechargeable battery is avoided. In an alternative embodiment, however, the surface cleaning apparatus of this invention can be incorporated into a vacuum cleaner.  
      The provision of the motor at the rear of the apparatus eliminates the need for increased height should the motor be positioned over the compartment for collecting dust and the like and also provides effective full width cleaning which would not be possible if the motor was to be positioned within the compartment for collecting debris. In another embodiment, the drive means for the brush arrangement passes at least partly through the debris compartment.  
       FIGS. 5, 6  and  7  depict another embodiment of a surface cleaning apparatus according to the invention. Apparatus  102  for cleaning a surface  104  comprises a housing  106 , suitably of moulded plastics material, and effectively having three compartments. A rear compartment  108  houses an electric motor  110  and a rechargeable battery pack  112 . The battery pack  112  may be connected to a mains power supply (not shown) for recharging the battery pack. The battery pack may either be connected to the mains supply whenever the apparatus is not in use or at suitable times when the battery pack has become depleted. Switch means  113  is provided to permit a user to energise and de-energise the motor  110  as desired. As an alternative to a rechargeable battery pack, the apparatus could employ disposable batteries or be mains powered.  
      A forward compartment  114  houses a transversely-arranged elongate rotatable brush arrangement  116 , with bristles  118 . Such elongate rotatable brush arrangement  116  is sometimes known as a brush bar. The bottom of the forward compartment  114  is open at  120  to allow the bristles  118  of the elongate brush arrangement  116  to contact a floor, carpet or the like over which the apparatus is to be propelled. The rear of the forward compartment is a rearwardly inclined wall  122  which allows debris to be propelled up the wall due to rotation of the brush arrangement  116  and to pass over the wall into an intermediate compartment  124 . The front of the forward compartment is provided with a front wall (not shown) which comprises the front face of body of the apparatus and which may be removable if desired. Debris accumulating in the intermediate compartment  124  can be removed by opening a cover  126 . The wall  122  extends upwardly to about the same height as the top of the elongate brush arrangement  116  and may be angled rearwardly (i.e. away from the forward compartment) such as at an angle of about 18 degrees. The precise angle is not important, but the inclination facilitates the passage of the debris up and over the wall  122  and at the same time facilitates retention of the debris within the intermediate compartment  124 .  
      The elongate brush arrangement  116  is rotated by the motor  110  by way of toothed rollers  128 ,  130  attached to the motor and to the brush arrangement, respectively, and by way of a toothed belt  131 , for example of elastomeric material, extending around the two rollers. The toothed belt  131  is enclosed within a tunnel  132  where it passes through or alongside the intermediate compartment  124  in order to prevent the ingress of debris into the rear compartment  108 .  
      An auxiliary brush means  134  is provided extending in an additional housing  170  outwardly from the apparatus housing  106  at the right hand side of the elongate rotatable brush arrangement  116  as viewed from above and behind the apparatus  102 . The auxiliary brush means  134  is of substantially circular form and is supported for rotation about an axis  136 , which may be vertical or inclined to vertical, such as at an angle of about 10 degrees to vertical. The auxiliary brush means  134  has a body  138  provided with radial bristles  140  which are inclined at an acute angle to the axis of rotation  136  so as to effectively form a conical arrangement increasing in cross-section with increasing distance from the body  138 .  
      The auxiliary brush means  134  is rotatably driven from the rotating elongate brush arrangement  116  by a gear wheel  142  at the end of the elongate brush arrangement  116  which meshes with a further gear wheel  144  on the body  138  of the auxiliary brush means  134 . The auxiliary brush means  134  is caused to be rotated in an anti-clockwise direction denoted by arrow  146 , as viewed from above and behind the apparatus  102 . During such rotation of the auxiliary brush means  134 , a peripheral region thereof rotates from a sideways-directed position  148  ( FIG. 7 ) outside the housing  106  to an opposed sideways-directed position  150  covered by the housing  106 , through a forwardly-directed position  152 .  
      The apparatus  102  is provided with a handle  154  by means of which it can be propelled at least in a forwards direction  156 . Wheels  158  and  160  are provided to enable or assist manual propulsion of the apparatus across the surface  104  to be swept, such as a floor, stairway or upholstery. The handle  154  could be longer, or be of a different shape or form, as required.  
      The rotating auxiliary brush means  134  does not rely on contact with the surface  104  for its rotation and therefore provides more efficient sweeping of edge regions of the surface  104  regardless of the nature of the surface  104 . Furthermore, the direction of rotation  146  of the auxiliary brush means  134  ensures that debris is swept positively by the auxiliary brush arrangement  134  into a position ahead of the rotating elongate rotating brush assembly  116 , ready to be picked up by the elongate brush arrangement  116 .  
      If desired, instead of or in addition to the auxiliary brush means  134  provided extending outwardly from the right hand side of the housing  106 , a similar auxiliary brush means (not shown) could likewise be provided extending in an additional housing outwardly from the left hand side of the housing  106  and driven from the opposite end of the elongate brush arrangement  116 . Such additional or alternative auxiliary brush means differs from the auxiliary brush means  134  only in that it is caused to rotate in a clockwise, rather than anti-clockwise, direction as viewed from above and behind the apparatus  102 .  
      The additional housing  170  and the front wall  201  of the surface cleaning apparatus may be attached to the main housing  106  by means of clips (not shown). Therefore the additional housing  170  and the front wall  201  can be detached from the main housing  106  of the apparatus without the need for tools, to facilitate maintenance and/or repair of the elongate brush arrangement  116  and the auxiliary brush means  134 .  
      Instead of the apparatus  102  being provided with a battery or mains powered electric motor  110  to drive the elongate brush arrangement  116  and hence the auxiliary brush means  134 , a known form of friction drive means (not shown), resulting from propulsion of the apparatus  102  along the surface  104 , may be utilised to effect rotation of the elongate brush arrangement  116  and hence rotation of the auxiliary brush means  134 .  
      Although the front wall of the surface cleaning apparatus has been described as comprising a single recess such that the lower edge of the wall is non-planar it should be understood that the wall can comprise a plurality of recesses, or the lower edge can have an undulating surface such that the distance between the lower edge and the surface being cleaned can vary depending on the undulations.  
      Persons of ordinary skill in the art will recognize that many modifications may be made to the present invention without departing from the spirit and scope of the present invention. The embodiments described herein are meant to be illustrative only and should not be taken as limiting the invention, which is defined by the following claims.