Patent Publication Number: US-2012030892-A1

Title: Dust sheet for self-propelled floor cleaner

Description:
TECHNICAL FIELD 
     The present invention relates to an improvement of a dust sheet for a self-propelled floor cleaner. 
     BACKGROUND ART 
     A self-propelled floor cleaner having an annular dust sheet  1  attached to a bottom surface of disk-shaped main body parts  14  and  15  is available (refer to Non-Patent Document 1 and Patent Document 1). 
     A self-propelled floor cleaner of Non-Patent Document 1 moves with a wheel provided on a center portion of the bottom surface of a disk-shaped main body  14  (refer to  FIG. 13 ). 
     A self-propelled floor cleaner of Patent Document 1 has a ball  13  as a driving device in a hat-shaped main body  15  with its upper surface being open. The center of weight of this ball  13  is changed by an accommodated driving gear to cause movements (refer to  FIG. 14 ). 
     In any of the self-propelled floor cleaners, the main part  14  or  15  moves in a direction changed when colliding with a wall surface of a room, and the dust sheet  1  attached to the bottom surface of the main part  14  or  15  wipes a floor  17 . 
     At power-on, the cleaner is self-propelled all over the room to clean the floor, which is extremely convenient. However, since the main part  14  or  15  is in a disk shape so as not to damage the walls of the room and the dust sheet  1  has a size approximately the same as the bottom part of the main part  14  or  15 , corners  16  of the floor cannot be wiped. 
     PRIOR ART DOCUMENTS 
     Patent Document 
     Patent Document 1: Japanese Patent No. 3681728 
     Non-Patent Document 
     Non-Patent Document 1: Homepage of Flooring Cleaning Robot Moppy 
     SUMMARY OF THE INVENTION 
     Problem to be Solved by the Invention 
     A problem to be solved by the invention is to make it possible to clean even corners of a floor. 
     Means for Solving the Problem 
     A dust sheet of the invention of claim  1  is formed of an annular sheet with a rear surface having a peelable removable structure, the dust sheet being affixed to a circular bottom part of a disk-shaped self-propelled floor cleaner to wipe a floor surface with movement of the self-propelled floor cleaner, wherein 
     the dust sheet has an outer perimeter provided with at least one protrusion extending therefrom and protruding sideward from the bottom part when affixed to the self-propelled floor cleaner, and an adhesive member attachable to an upper surface of the self-propelled floor cleaner is mounted on an upper surface of a tip part of the protrusion. 
     In a dust sheet of the invention of claim  2 , a plurality of the protrusions are provided at regular intervals. 
     A dust sheet of the invention of claim  11  is formed of an annular sheet with a rear surface having a peelable removable structure, the dust sheet being affixed to a circular bottom part of a disk-shaped self-propelled floor cleaner to wipe a floor surface with movement of the self-propelled floor cleaner, wherein 
     when the dust sheet is affixed to the self-propelled floor cleaner, the dust sheet extends off an entire perimeter from an outer perimeter of the bottom part, and many incisions are provided to at least an extending-off part in a direction from a center toward the outer perimeter. 
     The protrusion includes one shaped so as to all extend from the outer perimeter of the bottom part of the self-propelled floor cleaner with an increased annular part of the dust sheet. Also, the dust sheet includes those made of woven fabric, unwoven fabric, and paper. 
     Effect of the Invention 
     In the invention of claim  1 , the dust sheet has at least one protrusion provided so as to protrude from the circular bottom surface of the disk-shaped self-propelled floor cleaner. Therefore, with the protrusion, even parts that could not be reached so far can be wiped. Also, when the protrusion has its tip bent and affixed to the upper surface of the self-propelled floor cleaner, the tip becomes less prone to bend (the protrusion is prevented from bending to crawl into the bottom part of the self-propelled floor cleaner), thereby allowing smoothing cleaning of the corners of the floor. 
     In the invention of claim  2 , since multiple protrusions are provided at regular intervals, the dust sheet can smoothly rotate. 
     In the invention of claim  11 , the dust sheet smoothly bends when touching a corner of the floor, thereby every corner can be cleaned. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       [ FIG. 1 ]  FIG. 1  is a bottom view of a self-propelled floor cleaner having a dust sheet affixed thereto. 
       [ FIG. 2 ]  FIG. 2  is a side view of the self-propelled floor cleaner having the dust sheet affixed thereto. 
       [ FIG. 3 ]  FIG. 3  is a plan view of the self-propelled floor cleaner having the dust sheet affixed thereto. 
       [ FIG. 4 ]  FIG. 4  is a diagram for describing that the self-propelled floor cleaner cleans the corners of a floor. 
       [ FIG. 5 ]  FIG. 5  is a side view of a self-propelled floor cleaner of another reference example. 
       [ FIG. 6 ]  FIG. 6  is a perspective view of the self-propelled floor cleaner of still another reference example. 
       [ FIG. 7 ]  FIG. 7  is a plan view of the self-propelled floor cleaner having a dust sheet of another reference example affixed thereto. 
       [ FIG. 8 ]  FIG. 8  is a plan view of the self-propelled floor cleaner having a dust sheet of still another reference example affixed thereto. 
       [ FIG. 9 ]  FIG. 9  is a perspective view of the self-propelled floor cleaner having affixed thereto a dust sheet in a shape different from those in each drawing above. 
       [ FIG. 10 ]  FIG. 10  is a perspective view of the self-propelled floor cleaner having affixed thereto the dust sheet of  FIG. 9  with many incisions. 
       [ FIG. 11 ]  FIG. 11  is a diagram of the state in which a dust sheet of an embodiment is affixed to the self-propelled floor cleaner. 
       [ FIG. 12 ]  FIG. 12  is a diagram for describing dimensions of a protrusion. 
       [ FIG. 13 ]  FIG. 13  is a side view of a conventional self-propelled floor cleaner. 
       [ FIG. 14 ]  FIG. 14  is a perspective view of another conventional self-propelled floor cleaner different from that of  FIG. 13 . 
     
    
    
     BEST MODES FOR CARRYING OUT THE INVENTION 
     Embodiment and others of the self-propelled floor cleaner according to the present invention are described below with reference to the drawings. 
       FIG. 1  is a bottom view of a self-propelled floor cleaner having a dust sheet affixed thereto.  FIG. 2  is a side view of the self-propelled floor cleaner having the dust sheet affixed thereto.  FIG. 3  is a plan view of the self-propelled floor cleaner having the dust sheet affixed thereto. 
       1  denotes a dust sheet with an annular sheet  2  having multiple (in the drawings, seven) protrusions  3  provided outside. 
     The annular sheet  2  has a size similar to that of a conventional sheet, and has an outer perimeter approximately equal to the outer perimeter of the bottom part of a self-propelled floor cleaner. The protrusions  3  each have an acutely pointed tip. 
     The annular sheet  2  and the protrusions  3  are integrated together, and both are bendable and produced from paper or fabric (woven fabric or unwoven fabric). 
     As with a conventional dust sheet, this dust sheet  1  has a removable structure, such as a hook-and-loop fastener, on the rear surface as before, thereby being removable from the bottom surface  5  of a disk-shaped self-propelled floor cleaner  4  (refer to  FIGS. 2 and 3 ). 
     As with a conventional self-propelled floor cleaner, the self-propelled floor cleaner  4  has a disk shape, and has a traveling part  6  and obstacle detecting means (not shown) on a bottom part  5 . 
     The traveling part  6  is composed of three wheels, that is, paired rear wheels  6   a,    6   a  spaced a predetermined distance apart and a front wheel  6   b  positioned at a center ahead of the rear wheels  6   a,    6   a.  Upon receiving power from an incorporated power supply (not shown), the rear wheels  6   a,    6   a  rotate. The front wheel  6   b  rotates by being pushed by the rear wheels  6   a,    6   a,  and has its direction changed by a control part (not shown). 
     The obstacle detecting means is composed of one or more sensors of a type, such as a sensor detecting rotation or halt of the front wheel  6   b  or an infrared ray sensor in the form of radiating infrared rays toward front downward and, when detecting rotation or halt of the wheel, detecting a wall surface a predetermined distance ahead, or detecting that no more floor surface is present, instructs the front wheel  6   b  to change a traveling direction and rotate the self-propelled floor cleaner  4 . 
       7  denotes a rod-shaped member installed upright and spaced a predetermined distance apart from an outer circumferential part on an upper surface of the self-propelled floor cleaner  4 . In the drawing, eight such members are provided at regular intervals. 
     An upper end of this rod-shaped member  7  has a height equal to or higher than an upper end of the self-propelled floor cleaner  4 , and this rod-shaped member  7  serves as space height detecting means. 
     With the rear wheels  6   a,    6   a  rotating upon receiving power from the power supply (not shown) incorporated in a main body, the above-structured self-propelled floor cleaner  4  travels on the floor. Then, cleaning is performed with the dust sheet  1  affixed to a bottom part  5  wiping the floor. Then, when the obstacle detecting means detects a wall surface a predetermined distance ahead or detects that no more floor surface is present (when the front wheel  6   b  does not rotate, or the sensor detects a wall surface a distance ahead, or detects that nor more floor surface is present), the control part instructs the front wheel  6   b  to rotate the self-propelled floor cleaner  4  and change the traveling direction. 
     Also, at corners of the floor, the protrusions  3  wipe every corners appropriately bending, which were unable to be wiped so far. (refer to  FIG. 4 ). 
     Furthermore, when the self-propelled floor cleaner  4  enters a space under a chair and the rod-shaped member  7  collides with an obstacle to cause the front wheel  6   b  not to rotate or when a sensor  8  mounted on the rod-shaped member  7  senses as such, the control part instructs the front wheel  6   b  to rotate the self-propelled floor cleaner  4  and change the traveling direction. 
     Next, another reference example is described. 
     In this reference example, while the shape of the dust sheet  1  is identical to that of the above reference example, the shape of the self-propelled floor cleaner  4  is different. 
     As depicted in  FIG. 5 , the self-propelled floor cleaner  4  has a shape in which a disk-shaped lower main body part  9  has fixed thereon a columnar-shaped upper main body part  10  with its outer diameter a size smaller than that of the lower main body part  9 , and the height of the lower main body part  9  and the upper main body part  10  together is equal to that of the above embodiment (approximately 5 cm). This upper main body part  10  serves as space height detecting means. 
     And, as with the above reference example, a traveling part  6  that can freely change the traveling direction and obstacle detecting means (not shown) are provided on the bottom part  5  of the lower main body part  9 . 
     With the rear wheels  6   a,    6   a  rotating upon receiving power from the power supply (not shown) incorporated in a main body, the above-structured self-propelled floor cleaner  4  travels on the floor. Then, cleaning is performed with the dust sheet  1  affixed to a bottom part  5  wiping the floor. Then, when the obstacle detecting means detects a wall surface a predetermined distance ahead or detects that no more floor surface is present (when the front wheel  6   b  does not rotate, or the sensor detects a wall surface a distance ahead, or detects that nor more floor surface is present), the control part instructs the front wheel  6   b  to rotate the self-propelled floor cleaner  4  and change the traveling direction. 
     Also, when the self-propelled floor cleaner  4  enters a space under a chair and the upper main body part  10  collides with an obstacle to cause the front wheel  6   b  not to rotate or when a sensor  8  mounted on the upper main body part  10  senses as such, the control part instructs the front wheel  6   b  to rotate the self-propelled floor cleaner  4  and change the traveling direction. 
     Next, still another reference example is described. 
     Also in this reference example, while the shape of the dust sheet  1  is identical to that of each of the above reference examples, the shape of a self-propelled floor cleaner is different. 
     As depicted in  FIG. 6 , a self-propelled floor cleaner  11  includes a main body part  12  having a cylindrical member mounted in an inner perimeter part of an annular member and a spherical-shape traveling part  13  accommodated inside the cylindrical member. When the main body part  12  hits an obstacle, the traveling part  13  touches any of a plurality of vertical slots to rotate the self-propelled floor cleaner  4 , and the traveling part  13  changes the traveling direction. 
     Also in this reference example, as with each of the above reference examples, a rod-shaped member  7  may be provided to an outer perimeter part of an upper surface of the annular member. 
     While the dust sheet  1  has seven protrusions  3  extending outside the annular sheet  2  in each of the above reference examples, the number of protrusions may be one or more. However, if the number is too small, occasions to touch the corners of the floor decrease, contrary to the object of wiping every corner. Therefore, three or more may be preferably provided. 
     Also, while the protrusion  3  is assumed to have a tip acutely pointed, without limitation, the tip may be rounded as depicted in  FIG. 7 . However, unless the tip is acutely shaped (at an acute angle or with the acutely-shaped tip rounded), the protrusion  3  may possibly extend off each corner at 90°, being unable to wipe well. 
     Furthermore, the dust sheet  1  at least protrudes from the circular bottom part of the self-propelled floor cleaner, and may be in a triangular shape as depicted in  FIG. 8 . 
     Still further, as depicted in  FIG. 9 , the annular part may be in a shape larger than the outer perimeter of the bottom part of the self-propelled floor cleaner  4  to entirely extend off the bottom part. This means that the protrusion of the present invention includes the one having such a shape as described above. In this case, however, the protrusion needs to be made of a flexible thin material so as to be bendable to touch easily the corners of the floor. 
     Still further, as depicted in  FIG. 10 , the annular part may be in a shape larger than the outer perimeter of the bottom part of the self-propelled floor cleaner  4  to entirely extend off the bottom part and may have many incisions  19  in a direction from the center of the dust sheet toward the outer perimeter. The dust sheet smoothly bends when touching a corner of the floor, thereby every corner can be cleaned. 
     Still further, when the protrusion  3  has each tip bent as depicted in  FIG. 11  and affixed to the self-propelled floor cleaner  4  with an adhesive (in the embodiment), a hook-and-loop fastener, or the like, the tip becomes less prone to bend, thereby eliminating the possibility of being unable to wipe the corners. 
     Still further, the rod-shaped member(s)  7  and the upper main body part  10  need not be provided with the sensor  8 . This is because an equivalent control can be performed even without the sensor  8  as long as it is detected that the front wheel  6   b  does not rotate. 
     Note that the protrusion  3  may preferably protrude more than each corner  18  of a rectangle circumscribed around the circular bottom part of the self-propelled floor cleaner  4 . This is because, if it is shorter as depicted in  FIG. 12 , the protrusion  3  cannot touch each corner of the floor even when the self-propelled floor cleaner collides with a wall surface. 
     DESCRIPTION OF REFERENCE NUMERALS 
     
         
           1  dust sheet 
           2  annular sheet 
           3  sheet protrusion 
           4  self-propelled floor cleaner 
           6  traveling part 
           7  contact sensor