Abstract:
The present invention provides an interdental brush and a cap, said brush having a good handling property and a low manufacturing cost, said brush being stored with the cap on while adjusting the brush body at any angle. The handle member  3  supporting the brush body  2  includes a handle body  6,  an arm  12  extending from one end of the handle body  6,  a brush support  13  that holds a base of the brush body  2,  a first hinge  14  that connects the tip of the arm  12  and one end of the brush support  13  in a freely rotating manner, an operating portion  15  provided slidably at the other end of the handle member  3,  and a second hinge  16  that connects the tip of the operating portion  15  and the other end of the brush support  13  in a freely rotating manner.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of International Patent Application No. PCT/JP2004/016727, filed Nov. 11, 2004, which claims priority of Japanese Patent Application No. 2003-383772, filed Nov. 13, 2003. 
     
     TECHNICAL FIELD 
       [0002]    This invention relates to an adjustable interdental brush with a cap that can be attached and detached regardless of the brush body angle. 
       BACKGROUND 
       [0003]    The interdental brushes generally known and used consist of a handle and a brush body formed of a thin metal wire strand folded and twisted wherein a filament is captured between the wire. The brushes are generally cylindrical or cone-shaped and the handle is generally synthetic and often cylindrical of appropriate size to hold in the hand. A wire base of the brush body is often fixed onto the handle using methods such as insert molding and other physical joining methods including thermal fusion by high frequent and ultrasonic waves to integrate the brush body with the handle. 
         [0004]    The problem with such conventional interdental brushes is that the base was often bent to fit into the gap between teeth to insure the best angle between the handle member and the brush. Repeating this procedure will damage the wire quite easily in a fairly short time period. 
         [0005]    As a proposed solution, some interdental brushes have a handle, and a brush support member to fix and hold the brush body, with the tip of the handle branched in two on which the brush support member is pivotally supported in a freely rotating manner. (See Kokai Disclosure No. 9-121942 (Patent Document 1). However, such interdental brushes have the problem of increased manufacturing costs due to the increased number of parts necessary to make the brush support member. 
         [0006]    Another type of interdental brush has been proposed in which the handle is made of two sub-handles, right and left sub-handles symmetrically centered on a common axis to form one handle, with the tip of both sub-handles fixed via five rings with a wire support. (See Kokai Application No. 8-508179 (Patent Document 2). 
         [0007]    The interdental brush shown in Patent Document 2 adjusts the angle of the brush body against the handle by sliding the right and left sub-handles in the direction of the handle by which operation the cleaning action is enhanced. By forming the handle member so that these two sub-handles can open at an angle of 180°, the handle can be formed in one process whereby the number of parts and costs incurred are reduced. 
         [0008]    Patent Document 1: Kokai Disclosure No. 9-121942 
         [0009]    Patent Document 2: Kokai Application No. 8-508179 
       SUMMARY 
       [0010]    However, the problem with the interdental brush shown in Patent Document 2 lies in the fact that the handle member must be cast with the two sub-handles in the open position. This requires the surface area of the mold to be more than twice as large as that required for a conventional handle, negatively impacting productivity of manufacture. Moreover, to make a handle a convenient length to hold, a large mold is required, resulting again in increased cost. In addition, as this toothbrush adjusts the brush body by sliding the sub-handles, it is not easy to use due to the potential risk of accidentally sliding the sub-handle while using the interdental brush. As a result, interdental brushes made this way are generally small in size and hard to use. 
         [0011]    Here, an adjustable brush, which is easy-to-handle, cost-competitive and has a cap attachable to the brush regardless of its angle is disclosed. 
         [0012]    The interdental brush which meets the above requirements is one having a brush body and a handle member. The handle member consists of a handle, an arm extending from one end of the handle along the length of the handle, a brush support that holds the base of the brush body, a first hinge that connects the tip of the arm and one end of the brush support in a freely rotating manner, an operating portion situated in a position-changeable manner at the other end of the handle member and slidable along the length of the handle, and a second hinge that connects the tip of the operating portion and the other side of the brush support in a freely rotating manner. Changing a position of the operating portion along the handle&#39;s length enables the user to rotate the brush body about the hinge. 
         [0013]    The interdental brush may have a cap comprising a cap body covering the entire brush body, a cap base that is removably attachable to the brush support, and an opening formed by the cap base and cap body to cover the brush and the brush support. The cap preferably has an opening extending the length of the cap body and cap base to cover the entire brush body and brush support from the back. 
         [0014]    When the operating portion of the interdental brush has a sliding portion at the other end of the handle member that moves along the length of the handle, and when the above-mentioned position changing is done by sliding, moving the slide gives an optimum angle for the brush body depending on the gap between the teeth. This movement can be done easily and in a stable manner while holding the handle, with or without attaching the extension pipe. Thus, the operational performance of the interdental brush can be improved by fitting its brush angle to the gap between the teeth. 
         [0015]    Adding the position support means between the handle and the operating portion to keep the brush support at first and second positions centered on the first hinge can hold the brush at these switch-over positions, giving stability of the brush while cleaning, and hence, the operation of the brush can be enhanced by adjusting the brush angle to the optimum position. 
         [0016]    Connecting the tip of the arm to one end of the brush support via the first hinge and the tip of the operating portion and the other end of the brush support via the second hinge can hold the brush support at the alternative two positions centered on the first hinge, and the position of the brush body is stabilized while in operation and hence the operational performance of the brush is enhanced. In other words, for example, depicting the brush support as a square will locate both hinges at the ends of the diagonal line of the brush support, giving a distance between both hinges larger than that for the end-to-end length of the brush base. Thus, sliding the operating portion will generate a large slide friction due to the sideways movement, resulting in the operating portion being easy to hold at either of the two positions, and the brush support to be held in the two switch-over positions. 
         [0017]    The cap for the interdental brush comprises a cap body covering the entire brush and a detachable cap base that fit onto the brush body and brush support from the back. Thus, the cap fits quite easily and safely onto the brush body and brush support of the brush using the opening in the cap body and cap base. This is a benefit for elderly people with poor eyesight. In addition, because the cap is fitted to the brush support, the brush body angle can be adjusted easily and sanitarily while the cap is on it without using bare hands. Because the cap can be fitted to the toothbrush while holding the brush body at any angle, the brush can be stored while the brush body is disposed at any angle relative to the handle. 
         [0018]    References to directions (e.g., left/right, up/down) refer to the orientation within the various figures shown herein and are for convenience only. They should not be used to limit the invention. 
         [0019]    The productivity of manufacture of this interdental brush is increased and its cost reduced, as the handle, arm, brush support, operating portion, and hinges are integral parts of the handle member and can be molded in one process using synthetic resin. In addition, the handle length can be adjusted, making it convenient to hold by changing its size and by adding an extension pipe to form the handle of the brush. As it does not require opening the handle members to 180 degrees, unlike the brush shown in Patent Document 2, it does not require a large mold and hence, an easy-to-handle brush can be manufactured quite cost-effectively. Moreover, by adjusting the position of the operating portion along the length of the handle, an optimized angle of the brush body can be obtained to fit in the gaps between teeth and cleaning performance can be improved. Also, operation of the interdental brush can be improved, as it allows to hold stably the handle or the extension pipe connected thereto by hand. 
         [0020]    The cap for this interdental brush can fit the brush body and brush support with the cap body and cap base using the opening from the side, so that the cap can be attached to the brush for storage, whatever the angle of the brush body. Hence, the operation of attaching and detaching the cap from the toothbrush as well as the ease of storage with the cap attached can be enhanced. As the cap is held at the brush support, the brush angle can be adjusted with its cap on without touching the brush with bare hands, and the sanitary condition of the brush is maintained. 
     
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0021]      FIG. 1(   a ) is a front elevational view of the interdental brush;  FIG. 1(   b ) is a right side elevational view of the interdental brush of  FIG. 1(   a ). 
           [0022]      FIG. 2(   a ) is a cross-sectional view through line A-A of  FIG. 1  ( b );  FIG. 2(   b ) is a cross-sectional view through line B-B of  FIG. 1(   a ). 
           [0023]      FIG. 3(   a ) is a partial perspective view of the tiltable support;  FIG. 3(   b ) is a partial perspective view of the operating portion. 
           [0024]      FIG. 4  is a front elevational view of the interdental brush at the second position. 
           [0025]      FIG. 5(   a ) is a partial front cross-sectional view of a second embodiment of the interdental brush;  FIG. 5(   b ) is a right side elevational view of the interdental brush of  FIG. 5(   a ). 
           [0026]      FIG. 6(   a ) is a front elevational view of a third embodiment of the interdental brush at the first position;  FIG. 6(   b ) is a front elevational view of the interdental brush of  FIG. 6(   a ) at the second position. 
           [0027]      FIG. 7(   a ) is a partial front cross-sectional view of the cap and the interdental brush at the first position;  FIG. 7(   b ) is a cross-sectional view through line C-C of  FIG. 7(   a );  FIG. 7(   c ) is a right elevational view of the cap; and  FIG. 7(   d ) is a partial front cross-sectional view of the cap and the interdental brush at the second position. 
       
    
    
     DETAILED DESCRIPTION  
     Listing of Reference Numbers 
       1  Interdental brush 
       2  Brush body 
       3  Handle member 
       4  Wire 
       5  Brush 
       6  Handle body 
       10  Tiltable support portion 
       12  Arm 
       13  Brush support 
       14  First hinge 
       15  Operating portion 
       16  Second hinge 
       20  Slide guide 
       21  Stop 
       22  Cutout 
       23  Control portion 
       1 A Interdental brush 
       3 A Handle member 
       6 A Handle body 
       15 A Operating portion 
       30  Hole 
       31  Guiding plate 
       32  Slide hole 
       33  Engagement portion 
       34  Wider hole 
       1 B Interdental brush 
       3 B Handle member 
       6 B Handle body 
       15 B Operating portion 
       35  Recessed portion 
       36  Protrusion 
       50  Cap 
       51  Cap body 
       52  Cap base 
       53  Opening 
       54  Protrusion 
       55  Recessed portion 
       [0028]    As  FIG. 1  shows, the interdental brush  1  is comprised of the brush body  2  including the brush  5  and the wire  4 , and the handle member  3  supporting the brush body. 
         [0029]    The brush body  2  shown in  FIGS. 1 and 2  is made of thin wire  4  strands folded and twisted, and filaments captured radially by the wire  4 , in a well-known configuration. The profile of the brush  5  can be either cylindrical or conical. It can also be barrel-shaped with the outer diameter of the middle portion of the brush larger than that of the top or the bottom of it. The brush body  2  and handle can be made by a one-shot molding of synthetic resin, including the brush and its core support. 
         [0030]    As  FIGS. 1 to 4  show, the handle member  3  comprises a elongated handle  6  of appropriate size to hold in the hand and a tiltable support portion  10  attached to the upper end of the handle  6 . The brush body  2  is connected to the handle  6  in a freely movable manner by way of the tiltable support portion  10 . The handle member  3  is made of synthetic resin having a property capable of withstanding repeated bending of an integrally formed hinge and enough strength to serve as a handle, such as polyethylene, polypropylene or thermoplastic elastomer, and the handle member  3  is formed by one-shot molding by a method such as injection molding. 
         [0031]    As shown in  FIGS. 1(   a ) and  2 ( a ), the tiltable support portion  10  consists of an arm  12  extending upward from the left end (one side at the tip) of the upper, roughly even surface of the handle  6 , a brush support  13  with the bottom (the proximal end) of the wire  4  of the brush body  2  fixed therein, a first hinge  14  connecting the upper end of the arm  12  and left bottom end of the brush support  13  which rotate freely with respect to each other, an operating portion  15  at the right side (other side) of the handle member  3  in a manner that is freely slidable along the length of the handle  6 , and a second hinge  16 , comprising an integrally formed hinge, that connects the upper end of the operating portion  15  and the right upper end of the main body of the brush support  13  in a freely rotating and movable manner. The position of the brush support  13  is supported in a range of about 90 degrees centered on the first hinge  14  in a freely rotating and movable manner by operating the operating portion  15  upward or downward, between in a first position in  FIG. 1(   a ) with the brush body  2  directed upward or downward and in a second position in  FIG. 4  with the brush body  2  directed left or right direction. 
         [0032]    As  FIG. 1  shows, the L 1  length between the proximal end of the arm  12  and the first hinge  14  is almost equal to or slightly longer than the L 2  length between the right end of the bottom of the brush support  13  and the first hinge  14 . The L 3  length between the bottom of the brush support  13  and the second hinge  16  is almost equal to or slightly longer than the L 4  length between the right end of the handle  6  and the arm  12 . In addition, the upper surface of the handle  6  and the right surface of the arm  12  almost form a right angle. The same is true in the case of the angle between the lower surface of the brush support  13  and the right surface of the brush support  13 . When the brush support  13  is in the first position shown in  FIG. 1(   a ), the angle between the lower surface of the brush support  13  and the right surface of the arm  12  is almost at a right angle, whereas when the brush support is in the second position shown in  FIG. 4 , the lower surface of the brush support  13  is almost in contact with the right surface of the arm  12  (the lower side in  FIG. 1)  and the bottom surface of the brush support  13  is almost in contact with the upper surface of the handle  6  (the lower right side in  FIG. 1 ). In addition, in this second position, the second hinge  16  moves closer to the right end of the upper surface of the handle  6 . 
         [0033]    In this embodiment, the lengths and angles described above are for the purpose of enabling the rotation of the brush body  2  between the first and second positions shown in  FIGS. 1(   a ) and  4  over a range of rotation of approximately 90°. However, the range of rotation of the brush body  2  can be altered by changing these lengths and angles. 
         [0034]    In order to enable the operating portion  15  to slide only upward and downward freely along the handle  6 , a pair of slide guides  20  is formed extending along the upper handle  6 . A pair of stops  21  are formed on the opposite sides and at the lower end of the operating portion  15  to slidingly grip and fit into slide guides  20 . The operating portion  15  is thus slidingly fitted to the handle portion  6  with the stops  21  freely movable in the slide guides  20 . 
         [0035]    The front and the rear stops  21  are not disposed directly opposite each other, but are staggered a distance in an upward and a downward direction with respect to each other as are the front and the rear slide guides  20  in order to accommodate the stops  21  so that the handle member  3  can be molded by a pair of molds. It is possible to locate the stops  21  and slide guides  21  symmetrically in the front and the rear direction with respect to the handle  6 , though this would require slightly different molding configurations. 
         [0036]    Cutouts  22  are formed in each of the upper and the lower portion of the slide guides  20 , and the operating portion  15  can be fit onto the handle  6  by engaging the front and the rear stops  21  through the cutouts  22  into the slide guides  20  one after another, using the elasticity of the operating portion  15 . The control portion  23  is located between the upper and lower cutouts  22  which blocks the movement of the operating portion  15  downward by engaging the control portion  23  with the base of the stops  21 , when the brush body  2  is at the first position by moving the operating portion  15  upward, and which blocks the movement of the operating portion  15  upward by engaging the control portion  23  with the base of the stops  21 , when the brush body  2  is at the second position by moving the operating portion  15  downward. To move the operating portion  15  from the upper position to the lower position, or vice versa, the operating portion  15  should be forced to push upward or downward against the elasticity of the material beyond the control portion  23  to move the stops  21  to upper or lower cutouts  21 . A position maintaining means of the interdental brush  1  is structured by the cutouts  22 , control portion  23  and stops  21 . 
         [0037]    The interdental brush  1  is designed so that moving the operating portion  15  upward will make the brush body  2  and the brush support  13  rotate to the first position as shown in  FIG. 1  about the first hinge  14 , whereas moving the operating portion  15  downward will make the brush body  2  and the brush support  13  rotate to the second position about the first hinge  14 . By rotating the position of the operating portion  15 , cleaning can be done by changing the position of the brush body  2  to best suit the gap between the teeth. When the brush body  2  is in the first or second positions, the stops  21  on the operating portion  15  will engage the control portion  23  and cleaning can be done by stabilizing the brush body  2  at the appropriate position. The frictional engagement of the stops and slide guides is such that there is sufficient resistance that the angle of the brush body does not readily change during use, but the angle can be readily changed by the user. The ridges shown on operating portion  15  provide a tactile way for the user to overcome the frictional engagement and change the angle. 
         [0038]    In the preferred embodiment, an interdental brush  1  with a handle  6  of appropriate length for ease of handling is provided. However, other battery-driven interdental brushes or other handles can be used by adding a short detachable extension pipe, and the brush can substitute for any other battery-driven interdental brush. Here, the brush body  2  is permanently fixed to the handle member  3  by embedding a wire  4  in the brush support  13 . However, it is also applicable to a system in which the brush body  2  can be replaced. It&#39;s also possible to engage a brush integrally formed with a brush body and a brush support to a handle member by using stops means. 
         [0039]    In another embodiment, as shown in  FIG. 5 , the interdental brush  1 A has a handle member  3 A with an elongated hole  30  extending through the front and rear sides of the body at the upper right of the handle  6 A. A guiding plate  31  is attached at the right of the hole  30 . A narrow slide hole  32  in the middle of the guiding plate  31  is in communication with hole  30  to accept the engagement portion  33  that protrudes from the free end of the operating portion  15 A. Wider holes  34  are located at the upper and lower ends of the slide hole  32 . In this embodiment, when the engagement portion  33  is fitted into the upper large hole  34 , the brush body  2  together with the brush support  13  is kept in the first position. When the engagement portion  33  is engaged in the lower large hole  34 , the brush body  2  together with the brush support  13  is kept at the second position. Moving the operating portion  15 A upward and downward will move the engagement portion  33  through the narrowed portion of the slide hole  32  to move to the upper or lower large holes  34  to keep the brush body  2  at the first or second positions changeably. 
         [0040]    In another embodiment, the handle member  3 B of the interdental brush  1 B as shown in  FIG. 6 , has more than one recessed portion  35  in the shape of, for example, a dovetail groove. The recesses  35  are located at intervals along the upper right surface of the handle  6 B to receive the protrusion  36  on operating portion  15 . When the protrusion  36  is engaged in one of the recesses  35 , the brush  2  is held in the first or second position. To rotate the brush  2 , the protrusion is disengaged from the recess and the operating portion  15  is moved so that the protrusion  36  is engaged with the other recess  35 . Any number of recesses  35  can be formed in the handle  6 B to hold the brush  2  in a plurality of different positions. In this embodiment, the brush body  2  is structured in a position-changeable manner between the first and the second position by moving the operating portions  15 ,  15 A and  15 B upward or downward. But it&#39;s also possible to make a structure capable of being changed in a plurality of positions, more than one. 
         [0041]    The cap  50  can be used for interdental brush  1 ,  1 A and  1 B, as well as other types of interdental brushes. As  FIG. 7  ( a ) shows, the cap  50  consists of a cap body  51  that covers the entire brush body  2  and a cap base  52  that engages the brush support  13 . An opening is provided at the right side of the cap body  51  so that the cap  50  may be placed over the brush  2  and brush support  13 . 
         [0042]    As  FIGS. 7  ( b ) and ( c ) show, long thin protrusions  54  are formed on the front and rear opposite sides of inner surface of the cap base  52 . The front and rear sides of the brush support  13  are provided with recessed portions  55  to receive the protrusions  54 . The cap  50  is fitted to the brush support  13  by engaging the protrusions  54  with the recessed portions  55  so that the cap may be attached and detached from the brush support  13 . The cap  50  thus may cover the entire brush body  2  and the brush support  13 . Alternatively, a hook system can be used to engage the cap base  52  to the brush support  13 . 
         [0043]    The cap  50  can be fitted to the interdental brush  1  while holding the brush body  2  and the brush support  13  in the first position as shown in  FIG. 7  ( a ) or the second position as shown in  FIG. 7  ( d ) and the interdental brush  1  can be stored in these respective positions with the cap  50  on. Therefore, the ease of fitting the cap  50  onto the interdental brush  1  and the ease of storing the interdental brush  1  with the cap  50  on is significantly enhanced. In addition, as the cap base  52  engages the brush support  13  to fix the cap  50  to the brush support  13 , the angle of the brush body  2  is adjustable while the cap  50  is on, to maintain sanitary conditions without touching the brush body  2 . 
         [0044]    The embodiments described above and illustrated in the figures are presented by way of examples only and not intended as a limitation upon the concepts and principles of the present invention. As such, it will be appreciated by one having ordinary skill in the art that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention.