Patent Publication Number: US-8117706-B2

Title: Manual cleaning instrument

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. §119 to Japanese Patent Application no. 2008-052843, filed in Japan on Mar. 4, 2008, the entire contents of which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The present invention relates to a manual cleaning instrument which is suitable for cleaning carpets, tatami (straw floor mats), flooring, sofas, chairs, vehicle compartments, and the like. 
     2. Prior Art 
     Cleaning instruments which employ a roll of adhesive tape, such as that disclosed in Japanese Unexamined Patent Application Publication 2003-265401, are widely used as conventional manual cleaning instruments. This cleaning instrument has advantages in terms of being compact and easy to store, and also in terms of ease of use. On the other hand, it is necessary to peel the adhesive tape off one sheet at a time once the dust collection has finished, and dispose of it, and this subsequent operation is a burden for the user. There is a further problem in that the cleaning instrument itself gets rid of detritus other than the dust which has been trapped, and therefore there is an increase in the overall amount of detritus. An additional problem is that most of the exposed face is covered by adhesive tape, and therefore the roll of adhesive tape adheres to surrounding articles when cleaning in tight places, such as under a bed, and the instrument cannot be moved smoothly. 
     There are also manual cleaning instruments which do not employ adhesive tape, such as that disclosed in Japanese Unexamined Patent Application Publication 2004-329618. This is an instrument which makes it possible to collect fibrous dust which has become entangled on carpets etc. when it is pushed against the floor surface, or the like, and moved back and forth. However, it is necessary to move the instrument back and forth while pressing it from above, and therefore it is difficult to reach into tight spaces such as under a bed. Furthermore, the back and forth movement sometimes produces an unpleasant clattering sound and vibration. It is also necessary to separate upper and lower cases in order to dispose of the dust collected. 
     SUMMARY OF THE INVENTION 
     Issues to be Resolved by the Invention 
     There is therefore a demand for a manual cleaning instrument with which collected dust can be easily disposed of, which enables cleaning in tight spaces, which is silent, and which is comfortable to use, and this is achieved without producing waste such as adhesive tape. 
     Means of Resolving the Issues 
     The present invention has been devised in order to resolve the issues outlined above, and an embodiment of the invention disclosed is a manual cleaning instrument furnished with: a base which has an internal space and which is provided with an introduction port for taking in dust by the communication of said internal space with the outside at the lower part, and also provided with a discharge port for discharging dust by the communication of the abovementioned internal space with the outside at the upper part, and moreover in which said discharge port is provided with a lid; a hollow dust trapping body which is held inside the abovementioned internal space of the abovementioned base so as to be able to revolve in a front-to-rear direction, and which is provided with a dust collection opening at the top; and a front dust removal body and a rear dust removal body which are held in the abovementioned base in positions to the front and rear of the abovementioned dust trapping body, and which are constantly urged so that the dust removal faces thereof abut the abovementioned dust trapping body, wherein the abovementioned dust trapping body has an outer peripheral face which is arcuate in cross section with the axis of revolution at the center, and part of said outer peripheral face is exposed from the abovementioned introduction port, and also a protrusion which protrudes radially outward and divides the abovementioned outer peripheral face into two regions, namely a front region and a rear region, is provided in the center of the peripheral length of the abovementioned outer peripheral face; a front dust trapping brush comprising an inclined pile whereof the tip ends are directed toward the front edge of the abovementioned dust collection opening of the abovementioned dust trapping body is provided in the abovementioned front region; a rear dust trapping brush comprising an inclined pile whereof the tip ends are directed toward the rear edge of the abovementioned dust collection opening of the abovementioned dust trapping body is provided in the abovementioned rear region; the abovementioned dust removal faces of each of the abovementioned front dust removal body and the abovementioned rear dust removal body face the abovementioned front region and the abovementioned rear region, respectively; a front dust removal brush comprising an inclined pile whereof the tip ends are directed toward the front edge of the abovementioned dust collection opening of the abovementioned dust trapping body is provided on the abovementioned dust removal face of the abovementioned front dust removal body; a rear dust removal brush comprising an inclined pile whereof the tip ends are directed toward the rear edge of the abovementioned dust collection opening of the abovementioned dust trapping body is provided on the abovementioned dust removal face of the abovementioned rear dust removal body; a handle which extends rearward is provided in the center in the direction of axial revolution of the abovementioned base; and a buffer member with which the edge of the abovementioned dust collection opening of the abovementioned dust trapping body in the direction of revolution comes into contact when the abovementioned dust trapping body has revolved a prescribed angle is provided in the abovementioned base. 
     According to an embodiment of the invention disclosed, dust can be collected simply by placing the manual cleaning instrument in contact with the surface to be cleaned and moving it back and forth. At this time, the revolution of the dust trapping body is limited by the buffer member, and therefore no unpleasant noise of impact is generated. Furthermore, a user can easily access tight spaces by grasping the handle. 
     An embodiment of the invention disclosed is a manual cleaning instrument, wherein the front edge of the abovementioned lid is pivotably supported at the front edge of the abovementioned discharge port, and a tongue piece which extends from the rear edge of the abovementioned lid latches onto an engaging part provided on the abovementioned handle. 
     According to an embodiment of the invention disclosed, dust can be released while the handle is still being gripped so the collected dust can be discharged. 
     An embodiment of the invention disclosed is a manual cleaning instrument as claimed, wherein provision is further made for a pair of wheels which are held on the abovementioned body so as to be able to revolve in the same direction as the direction of revolution of the abovementioned dust trapping body. 
     According to an embodiment of the invention disclosed, it is possible to suppress the unpleasant vibration which is produced when the manual cleaning instrument is pulled forward. 
     Effects of the Invention 
     According to the present invention, it is possible to provide a manual cleaning instrument with which it is possible to collect dust simply by gripping the handle and moving the manual cleaning instrument back and forth while the dust trapping body is in contact with the surface to be cleaned. At this time, the revolution of the dust trapping body is restricted by the buffer member, and therefore no unpleasant impact noise is produced. Furthermore, it is possible to clean in tight spaces by gripping the handle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an oblique view showing the manual cleaning instrument according to a first embodiment of the present invention; 
         FIG. 2  is a view in transverse section showing the cross section A-A in  FIG. 1 ; 
         FIG. 3  is a view of the bottom face and a partial view in section showing the cross section B-B in  FIG. 2 , which shows the manual cleaning instrument according to the first embodiment of the present invention; 
         FIG. 4  is a view in cross section showing the state in which the manual cleaning instrument according to the first embodiment of the present invention has been advanced; 
         FIG. 5  is a view in cross section showing the state in which the manual cleaning instrument according to the first embodiment of the present invention has been moved back; 
         FIG. 6  is an oblique view showing the manual cleaning instrument according to a second embodiment of the present invention; and 
         FIG. 7  is a view of the bottom face and a partial view in section showing the manual cleaning instrument according to the second embodiment of the present invention. 
     
    
    
     REFERENCE NUMERALS 
     
       
         
           
               
               
               
               
             
               
                   
               
             
            
               
                  1 
                 manual cleaning instrument 
                  2 
                 base 
               
               
                  21 
                 introduction port 
                  22 
                 discharge port 
               
               
                  23 
                 side wall 
                  24 
                 side wall 
               
               
                 241 
                 retaining hole 
                  25 
                 bearing 
               
               
                  26 
                 spacer wall 
                 261 
                 retaining hole 
               
               
                  27 
                 axle 
                 271 
                 recess 
               
               
                  28 
                 lid 
                 281 
                 open/close shaft 
               
               
                 282 
                 tongue piece 
                 283 
                 latching part 
               
               
                 284 
                 knob 
                 285 
                 cylindrical wall 
               
               
                 286 
                 cover 
                  3 
                 dust trapping body 
               
               
                  31 
                 dust collection opening 
                 311 
                 edge 
               
               
                  32 
                 peripheral wall 
                  33 
                 side wall 
               
               
                  34 
                 projection 
                  35 
                 protrusion 
               
               
                  36a 
                 front dust trapping brush 
                  36b 
                 rear dust trapping brush 
               
               
                  37 
                 dust collection chamber 
                  4a 
                 front dust removal body 
               
               
                  4b 
                 rear dust removal body 
                  41 
                 pivot shaft 
               
               
                  42 
                 spring 
                  43a 
                 front dust removal brush 
               
               
                  43b 
                 rear dust removal brush 
                  5 
                 wheel 
               
               
                  51 
                 projection 
                  6 
                 buffer member 
               
               
                  7 
                 handle 
                  71 
                 engaging part 
               
               
                 711 
                 projection 
               
               
                   
               
            
           
         
       
     
     SPECIFIC EMBODIMENTS OF THE PRESENT INVENTION 
     A description will be given next of modes of embodiment of the present invention, based on the figures. Note that the modes of embodiment described below are preferred modes of embodiment of the present invention, and therefore there are various preferable technical limitations, but the scope of the present invention is not limited to these modes, unless it is particularly stated in the following description that there is a limitation in the present invention. 
     Mode of Embodiment 1 
     The manual cleaning instrument according to Mode of Embodiment 1 of the present invention is shown in  FIGS. 1-3 .  FIG. 1  is an oblique view showing the manual cleaning instrument according to Mode of Embodiment 1,  FIG. 2  is a view in transverse section showing the cross section A-A in  FIG. 1 , and  FIG. 3  is a view of the bottom face and a partial view in section showing the cross section B-B in  FIG. 2 . Note that in the description given hereinafter the left in  FIG. 2  to shall refer to the front, and the right shall refer to the rear. 
     The main structural elements of the manual cleaning instrument  1  according to this mode of embodiment consist of: a base  2  which is prolonged by a handle  7  for the user to grasp; a substantially cylindrical dust trapping body  3  which is pivotably held inside the base  2 ; and a front dust removal body  4   a  and rear dust removal body  4   b  which abut the dust trapping body  3 . “Pivot” in this instance means a turning motion on a single axis through less than 360°. The base  2  and handle  7  may be separate members which are assembled as a single piece, or the handle  7  portion may be produced by bonding separate components, but in this mode of embodiment the base  2  and handle  7  are made of integrally molded plastic. 
     As shown in  FIGS. 2 and 3 , the base  2  is provided with side walls  23 ,  23 ,  24 ,  24 , and an opening is formed at the upper and lower faces. The opening at the lower face is an introduction port  21  for taking in dust, and the opening at the upper face is a discharge port  22  for discharging collected dust. 
     A bearing  25  for holding an open/close shaft  281  provided on a lid  28  is formed at the front edge of the discharge port  22  in order to pivotably hold the lid  28 . 
     An engaging part  71  is sunk into the handle  7 , and when the discharge port  22  is closed, a tongue piece  282  which projects rearward from the lid  28  is housed therein. A minute projection  711  for latching onto the tongue piece  282  is formed inside the engaging part  71 , and this allows latching when the lid  28  is in a closed state. 
     As shown in  FIG. 3 , circular retaining holes  241 ,  241  for pivotably holding the dust trapping body  3  are arranged on the same axis in the central part of the respective left and right side walls  24 ,  24  of the base  2 . In this mode of embodiment, the retaining holes  241  do not pass all the way through, but it is feasible for them to do so. Furthermore, a hanging hole  72  which can be used to hang the manual cleaning instrument  1  from a hook or to pass a thread through is formed passing vertically through the rear part of the handle  7 . 
     The dust trapping body  3  is pivotably held inside the base  2 . The dust trapping body  3  comprises a peripheral wall  32  and side walls  33 ,  33 , and it is a hollow, substantially semi-cylindrical member comprising a dust collection opening  31  at the top. In this mode of embodiment, a dust collection chamber  37  is delimited by the peripheral wall  32  and side walls  33 ,  33  which are integrally molded from plastic. Projections  34 ,  34  which are formed so as to project from the side walls  33 ,  33  coaxially with the center of the peripheral wall  32  are inserted into the retaining holes  241  which are provided in the side walls  24  of the base  2  so that the dust trapping body  3  is pivotably held by means of the base  2 . In this instance, the dust trapping body  3  is attached to the base  2  in a state in which part of the outer peripheral face is exposed, projecting somewhat further downward than the lower end edge of the introduction port  21 . 
     A protrusion  35  is provided on the outer peripheral face of the dust trapping body  3 , projecting radially outward in the center of the peripheral length thereof. The protrusion  35  comes into contact with the surface to be cleaned, and therefore it is preferably made of a soft material so as not to damage the surface to be cleaned, and a material with a large friction coefficient is preferable so as to allow the dust trapping body  3  to rotate by means of the friction with the surface to be cleaned. A rubber material is therefore suitable as the material for the protrusion  35 . Furthermore, in this mode of embodiment, one protrusion  35  is provided so as to extend along virtually the whole length of the dust trapping body  3 , but it is also feasible to provide a plurality of protrusions which are split in the axial direction. 
     The outer peripheral face of the dust trapping body  3  is divided into two regions, namely a front region and a rear region with the protrusion  35  as the boundary, a front dust trapping brush  36   a  comprising a short inclined pile whereof the tip ends are directed toward the front edge  311   a  of the dust collection opening  31  being provided in the front region, and a rear dust trapping brush  36   b  comprising a short inclined pile whereof the tip ends are directed toward the rear edge  311   b  of the dust collection opening  31  being provided in the rear region. 
     The base  2  is provided with a pair of left and right spacer walls  26 ,  26  which are parallel to the two left and right side walls  24 ,  24  and whereof the lower part is cut away in a semi-circular shape. A pair of retaining holes  261   a ,  261   a  and a pair of retaining holes  261   b ,  261   b  which are respectively provided on the left and right spacer walls  26 ,  26  are arranged on the same respective axis, and a front dust removal body  4   a  and rear dust removal body  4   b  (which will be described later) are pivotably held in that place. 
     As shown in  FIG. 2 , the front dust removal body  4   a  and rear dust removal body  4   b  are respectively provided between the side walls  23 ,  23  of the base  2  and the dust trapping body  3 . The faces of the front dust removal body  4   a  and rear dust removal body  4   b  which face the dust trapping body  3  are formed as a gentle arc shape. A pivot shaft  41  which projects outward to the left and right is formed at the upper part of the front dust removal body  4   a  and rear dust removal body  4   b , respectively, and the front dust removal body  4   a  and rear dust removal body  4   b  are able to pivot with the pivot shaft  41  at the center by insertion of said pivot shaft  41  into the retaining hole  261  of the spacer wall  26 . A spring  42  is provided around the outside of said pivot shaft  41 , and the front dust removal body  4   a  and rear dust removal body  4   b  are urged toward the dust trapping body  3  by means of the spring force of the spring  42 . In this mode of embodiment, a torsion spring is used as the spring  42 , but a compression spring or a plate spring may be used instead of this. Furthermore, it is also possible to mold the front dust removal body  4   a  and rear dust removal body  4   b  as a single piece with the base  2 , without using a separate spring, and the front dust removal body  4   a  and rear dust removal body  4   b  can be urged toward the dust trapping body  3  by being provided extending from the side wall  23 . 
     A front dust removal brush  43   a  comprising a short inclined pile whereof the tip ends are directed toward the front edge  311   a  of the opening  31  of the dust trapping body  3  is provided on the face of the front dust removal body  4   a  which faces the dust trapping body  3 , and a rear dust removal brush  43   b  comprising a short inclined pile whereof the tip ends are directed toward the rear edge  311   b  of the opening  31  of the dust trapping body  3  is provided on the face of the rear dust removal body  4   b  which faces the dust trapping body  3 . The front dust removal body  4   a  and rear dust removal body  4   b  are constantly urged by means of the spring  42 , and therefore the front dust removal brush  43   a  and front dust trapping brush  36   a  are in constant abutment, and the rear dust removal brush  43   b  and rear dust trapping brush  36   b  are in constant abutment. 
     The lid  28  which is substantially rectangular when seen as a plane is fitted to the discharge port  22  of the base  2  in such a way that in can open and close. The lid  28  in this mode of embodiment comprises the open/close shaft  281  at the front, and it is supported by the bearing  25  provided in the base  2 , and therefore it can pivot with the open/close shaft  281  at the center. In addition, the tongue piece  282  projects rearward from the lid  28 , and a latching part  283  which forms part of the tongue piece  282  engages with a projection  711  inside the engaging piece  71  which is sunk into the handle  7 , whereby the lid  28  can be closed. Furthermore, a knob  284  is formed at the tip end of the tongue piece  282 , and pushing the knob  284  upward allows the engagement to be released and the lid  28  to be opened. A configuration can be adopted here in which a torsion spring is provided between the open/close shaft  281  and bearing  25 , so that an urging force is constantly imparted to the lid  28 , and when the knob  284  is pushed up, the lid  28  opens with force. Moreover, the lid  28  is preferably made from transparent plastic so that it is possible to ascertain the amount of dust which has been collected without having to open the lid  28 , but the color and shape of the lid  28  may be appropriately selected. 
     As shown in  FIG. 2 , a cylindrical wall  285  projects from the lid  28  toward the dust trapping body  3 , and a buffer member  6  made of a soft material and shaped like a doughnut is provided around the outside of the cylindrical wall  285 . The buffer member  6  is disposed at a position which is an extension of the peripheral wall  32  of the dust trapping body  3  in the circumferential direction. By means of this, when the dust trapping body  3  pivots through a prescribed angle, the structure can be designed so that the edges  311   a , and  311   b  of the dust collection opening  31  of the dust trapping body  3  come into contact with the buffer member  6 . That is to say, it is possible to prevent impact noise from being produced by contact between the protrusion  35  and the dust removal bodies  4 . 
     A description will be given next of the state of use for the mode of embodiment described above. The handle  7  of the manual cleaning instrument  1  of this mode of embodiment is grasped, the dust trapping body  3  which is exposed from the introduction port  21  is brought into contact with the surface to be cleaned, and the manual cleaning instrument  1  is moved forward. When this is done, the protrusion  35  which projects from the dust trapping body  3  comes into contact with the surface to be cleaned, and is subjected to a rearward friction force, and therefore the dust trapping body  3  rotates in a counter-clockwise direction in  FIG. 2  and the edge  311   b  of the dust collection opening  31  comes into contact with the buffer member  6 , which stops the rotation. A cross section of the instrument at this time is shown in  FIG. 4 . Then, if the manual cleaning instrument  1  is moved further forward, dust on the surface to be cleaned is picked up and trapped by the front dust trapping brush  36   a  which is exposed at the bottom from the introduction port  21  of the base  2 . 
     Next, when the manual cleaning instrument  1  is moved back, the protrusion  35  which projects from the dust trapping body  3  is subjected to a forward friction force, and therefore the dust trapping body rotates in a clockwise direction in  FIG. 2 , and the edge  311   a  of the dust collection opening  31  comes into contact with the buffer member  6 , which stops the rotation. A cross section of the instrument at this time is shown in FIG.  5 . Note that in this state, dust which has been trapped on the front dust trapping brush  36   a  remains adhered to the front dust trapping brush  36   a . Then, if the manual cleaning instrument  1  is moved further back, dust on the surface to be cleaned is picked up and trapped by the rear dust trapping brush  36   b  which is exposed at the bottom from the introduction port  21  of the base  2 . 
     Next, when the manual cleaning instrument  1  is moved forward once again, the protrusion  35  which projects from the dust trapping body  3  comes into contact with the surface to be cleaned, and is subjected to a rearward friction force, and therefore the dust trapping body  3  starts to rotate in a counter-clockwise direction in  FIG. 2 . At this time, dust which has adhered to the front dust trapping brush  36   a  is picked up by the front dust removal brush  43   a  which it abuts, and this dust is transferred to the front dust removal brush  43   a . Then, the edge  311   b  of the opening  31  comes into contact with the buffer member  6 , which stops the rotation, and the state shown in  FIG. 4  is reached. At this time, dust does not adhere to the front dust trapping brush  36   a  which is exposed at the bottom from the introduction port  21  of the base  2 . Then, when the manual cleaning instrument  1  is moved further forward, dust on the surface to be cleaned is picked up and trapped by the front dust trapping brush  36   a  which is exposed at the bottom from the introduction port  21  of the base  2 . 
     Next, when the manual cleaning instrument  1  is moved back once again, the protrusion  35  which projects from the dust trapping body  3  comes into contact with the surface to be cleaned, and is subjected to a forward friction force, and therefore the dust trapping body  3  starts to rotate in a clockwise direction in  FIG. 2 . At this time, dust which has adhered to the rear dust trapping brush  36   b  is picked up by the rear dust removal brush  43   b  which it abuts, and this dust is transferred to the rear dust removal brush  43   b.    
     Meanwhile, dust which has adhered to the front dust removal brush  43   a  is picked up by the front dust trapping brush  36   a  which it abuts, taken up to the edge  311   a  of the opening  31 , and stored inside the dust collection chamber  37 . 
     Then the edge  311   a  of the opening  31  comes into contact with the buffer member  6 , which stops the rotation, and the state shown in  FIG. 5  is reached. At this time, dust does not adhere to the rear dust trapping brush  36   b  which is exposed at the bottom from the introduction port  21  of the base  2 . Then, when the manual cleaning instrument  1  is moved further back, dust on the surface to be cleaned is picked up and trapped by the rear dust trapping brush  36   b  which is exposed at the bottom from the introduction port  21  of the base  2 . 
     Next, when the manual cleaning instrument  1  is moved forward once again, the protrusion  35  which projects from the dust trapping body  3  comes into contact with the surface to be cleaned, and is subjected to a rearward friction force, and therefore the dust trapping body  3  starts to rotate in a counter-clockwise direction in  FIG. 2 . At this time, dust which has adhered to the front dust trapping brush  36   a  is picked up by the dust removal brush  43   a  which it abuts, and this dust is transferred to the dust removal brush  43   a.    
     Meanwhile, dust which has adhered to the rear dust removal brush  43   b  is picked up by the rear dust trapping brush  36   b  which it abuts, taken up to the edge  311   b  of the opening  31 , and stored inside the dust collection chamber  37 . 
     Then the edge  311   b  of the opening  31  comes into contact with the buffer member  6 , which stops the rotation, and the state shown in  FIG. 4  is reached. At this time, dust does not adhere to the front dust trapping brush  36   a  which is exposed at the bottom from the introduction port  21  of the base  2 . Then, when the manual cleaning instrument  1  is moved further forward, dust on the surface to be cleaned is picked up and trapped by the front dust trapping brush  36   a  which is exposed at the bottom from the introduction port  21  of the base  2 . 
     By repeating the process described above, dust on the floor to be cleaned is collected in the dust collection chamber  37 , passing by the front dust trapping brush  36   a  and rear dust trapping brush  36   b , and the front dust removal brush  43   a  and rear dust removal brush  43   b . That is to say, the user can remove dust simply by bring the manual cleaning instrument  1  into contact with the surface to be cleaned and moving it back and forth. 
     Moreover, the dust removal bodies  4  are urged by the spring  42 , and it is possible to create a gap between the front dust removal brush  43   a  and rear dust removal brush  43   b , and the front dust trapping brush  36   a  and rear dust trapping brush  36   b , and therefore even dust having a large particle size can be smoothly conducted to the dust collection chamber  37 . Furthermore, the abutment of the front dust removal brush  43   a  and rear dust removal brush  43   b  with the front dust trapping brush  36   a  and rear dust trapping brush  36   b  is maintained by virtue of constant urging, and therefore dust which has adhered can be reliably picked up between them. 
     Even if the dust trapping body  3  reaches its maximum relative rotation with respect to the base  2 , the position of the buffer member  6  is set so that the opening  31  is not oriented toward the introduction port  21 , in other words so that the edges  311  of the opening  31  are not exposed from the introduction port  21 . Furthermore, the discharge opening  22  of the base  2  is closed off by the lid  28 . Accordingly, there is no risk of dust which has entered the dust collection chamber  37  spilling out during use. Furthermore, the edges  311  come into contact with the buffer member  6  before the protrusion  35  comes into contact with the front dust removal body  4   a  and rear dust removal body  4   b , and therefore the instrument can be moved back and forth in an agreeable manner, without any unpleasant impact noise being produced by the front dust removal body  4   a  and rear dust removal body  4   b.    
     When the user wishes to discharge the dust which has built up, if he operates the knob  284  to release the engagement, the lid  28  pivots about the axis of the open/close shaft  281 , and the discharge port  22  is opened, exposing the dust collection chamber  37 . It is then possible to remove the dust which has collected in the dust collection chamber  37 . Moreover, the knob  284  is housed inside the engaging part  71  of the handle  7 , and therefore the user can open the lid  28  with one hand while still grasping the handle  7 , and the dust which has collected in the dust collection chamber  37  falls out and is completely discharged by turning the discharge port  22  downward. 
     Mode of Embodiment 2 
     A manual cleaning instrument according to Mode of Embodiment 2 of the present invention is shown in  FIGS. 6 and 7 .  FIG. 6  is an oblique view showing the manual cleaning instrument according to Mode of Embodiment 2, and  FIG. 7  is a view of the bottom face and a partial view in cross section. The manual cleaning instrument  1  according to this mode of embodiment is an instrument in which detachable wheels  5 ,  5  are provided at the left- and right-hand ends of the manual cleaning instrument of Mode of Embodiment 1. 
     An axle  27  is projectingly provided at the side walls  24 , coaxially with the retaining holes  241 . The wheels  5  can then be rotatably held on the base  2  by the engagement of a projection  51  on the wheel  5  with a recess  271  in the axle  27 . “Rotation” in this instance means a turning motion on a single axis through 360° or more. The wheels  5  are made of plastic, and they engage by the elastic force of the material, and therefore the user can remove the wheels himself by releasing the abovementioned engagement. 
     In addition, the lid  28  is provided with a cover  286  which covers the top part of the wheels  5 . By means of this, there is no risk of interference with items around the wheels  5  when the cleaning instrument  1  is introduced into tight spaces etc., and this is preferable for allowing smooth access. 
     A description will be given next of the action of the wheels  5 . As stated in Mode of Embodiment 1, the manual cleaning instrument  1  is moved back and forth to enable trapping of dust on the surface to be cleaned. At this time, the front dust trapping brush  36   a  and rear dust trapping brush  36   b  slide over the surface to be cleaned, but a friction force in the direction of advance and the opposite direction is produced between the surface to be cleaned and the front dust trapping brush  36   a  and rear dust trapping brush  36   b . Meanwhile, the user grasps the handle  7  and applies a force in the direction of advance in resistance to the friction force. At this time, the point of action of the force exerted by the user is necessarily above the point of action of the friction force, and therefore this offset in the points of action of the force causes a rotation moment to be exerted on the manual cleaning instrument  1 . 
     When the manual cleaning instrument  1  is moved forward, the direction of the rotation moment acting on the manual cleaning instrument  1  is the counter-clockwise direction in  FIG. 2 . That is to say, it acts in the direction which presses the dust trapping body  3  against the surface to be cleaned. This rotation moment enables contact between the dust trapping brushes  36  and the surface to be cleaned to be strengthened, which enhances the dust trapping effect. 
     In contrast to this, when the manual cleaning instrument  1  is moved backward, the direction of the rotation moment acting on the manual cleaning instrument  1  is the clockwise direction in  FIG. 2 . That is to say, it acts in the direction which raises the dust trapping body  3  from the surface to be cleaned. This being so, contact between the front dust trapping brush  36   a  and rear dust trapping brush  36   b  and the surface to be cleaned is weakened, and the magnitude of the friction force may cause the instrument to rise from the surface to be cleaned. In this case, the dust trapping effect is lessened. There is an additional risk of self-induced vibration being generated, whereby the dust trapping body  3  repeatedly jumps from the surface to be cleaned and becomes grounded thereon. The vibration is transmitted to the handle  7 , which imparts a disagreeable feeling to the user who is holding it. 
     If the wheels  5  are provided in this case, it is possible to constantly ensure contact between the manual cleaning instrument  1  and the surface to be cleaned, and a damping effect on the vibration is demonstrated between the wheels  5  and the base  2 , making it possible to suppress the generation of self-induced vibration. In addition, even if self-induced vibration is generated, the vibration is transmitted toward the wheels, and it is possible to block disagreeable vibration from being transmitted to the handle  7 . 
     Moreover, the friction force generated varies according to the material from which the surface to be cleaned is made, and it may also be possible to move the instrument smoothly back and forth even without the wheels. Consequently, the wheels  5  are preferably detachably provided at the left and right ends of the base  2  so that the user can attach or detach them as appropriate. 
     As described above, with the manual cleaning instrument according to the present invention, it is possible to automatically trap dust simply by bringing the instrument into contact with the surface to be cleaned and moving it back and forth, and moreover the dust which has been collected can be easily disposed of.