Abstract:
A toothbrush ( 10 ) is disclosed with soft fingers ( 16 ) mounted on the toothbrush head ( 14 ). During use of the tooth-brush the fingers move laterally relative to the axis of the tooth-brush thereby improving the tooth cleaning and gum massaging performance of the toothbrush. The lateral movement of the fingers is accomplished by relatively stiff ribs ( 24 ) which physically interconnect the fingers to flexible portions of the toothbrush head. The ribs translate flexure of the head into the lateral movement of the fingers.

Description:
This application is a national-stage filing under 35 USC 371 of International Application PCT/US2003/034108, filed on Oct. 24, 2003, which claims priority to U.S. Application 60/422,017 filed Oct. 28, 2002, both of which are incorporated by reference herein in their entirety. 

   BACKGROUND OF THE INVENTION 
   The present invention is directed to a toothbrush, either manual or powered, which includes a handle and a head. Cleaning elements are mounted to the head such as tufts of bristles. When toothpaste is applied to the cleaning elements the user inserts the head into the mouth and brushes the teeth in a known manner. 
   The head of a conventional toothbrush usually has a flat or slightly altered surface to which cleaning elements are attached. Usually the cleaning elements are strands of plastic material(s) formed into tufts, bundles or other groupings. The strands are attached to the head either before or after forming the toothbrush. 
   The toothbrush of the present invention facilitates more motion of cleaning elements in the toothbrush head thereby promoting healthy stimulation of gums and cleaner teeth. It is well known that the ideal brushing technique from a dental hygiene perspective is an up and down stroke along the vertical surface of teeth which massages the gums while cleaning the teeth. However, due to a number of factors, including ergonomic difficulties, haste, lack of education or the like, few consumers use the recommended brushing technique. Rather, the typical consumer brushes across their teeth in a horizontal motion rather than a vertical movement. Various approaches have been taken by others to translate horizontal brush movement into partial vertical movement of the bristles or cleaning elements. 
   Translation of horizontal to vertical movement of cleaning elements is accomplished in U.S. Pat. No. 4,783,869 through use of a helix groove in a movable shaft within a toothbrush handle. The groove receives a pin which rides in the groove. This mechanism causes the toothbrush head to partially rotate or oscillate as the handle moves left-to-right or vice versa in the user&#39;s mouth. That rotation or oscillation causes the cleaning elements to move in a vertical plane perpendicular to movement of the toothbrush handle. 
   U.S. Pat. No. 5,481,775 discloses an arcuate shaped base for a toothbrush. head aligned with the longitudinal axis of the head. A movable arcuate block containing cleaning elements is flexibly mounted on the toothbrush head. The block is free to slide on the head in a manner whereby the cleaning elements may travel in a vertical direction generally transverse to the typical side-to-side motion of the toothbrush. 
   U.S. Pat. No. 5,528,786 discloses pivotal mounting of cleaning elements that allows those elements to move up and down in concert with a side-to-side stroke along the teeth. 
   A general disclosure of flexible mounting for cleaning elements on a toothbrush head is contained in U.S. Pat. No. 5,839,149. In this patent the cleaning elements are mounted on a flexible membrane supported between a horseshoe shaped handle extension. 
   U.S. Pat. No. 6,141,817 discloses cleaning elements mounted on a flexible membrane that splay outward when the toothbrush is pressed against the user&#39;s teeth. 
   U.S. Pat. No. 6,338,176 B1 issued Jan. 15, 2002 to Smith, et al. discloses round sections of cleaning bristles mounted on individual pads that rotate within a toothbrush body. This converts backward and forward motion of the toothbrush into circular motion of the cleaning elements (column 1, lines 11-13). The bristles associated with each pad are of varying height to accommodate irregularities, gaps, pockets and contours in natural tooth formation (column 1, lines 40-45). The rotating cleaning elements can be supplemented with fixed cleaning elements adjacent thereto (FIG. 11; column 5, lines 43-49). 
   SUMMARY OF THE INVENTION 
   This invention provides transverse movement of cleaning elements relative to the longitudinal axis of a toothbrush head without the cumbersome hinges, mechanisms and helical channels described in the aforementioned prior art toothbrushes. Those prior art toothbrushes using mechanical means to introduce such movement have a common fault of creating interstices and voids in the toothbrush head that can harbor bacteria and germs. The mechanical parts also add to the manufacturing cost of such toothbrushes. 
   This invention improves the movement of cleaning elements relative to a toothbrush head. That movement is induced by adding appropriately configured fingers to groups of cleaning elements, which fingers are attached by ribs to a flexible head. The ribs are relatively thin, typically rectangular, webs that connect the fingers to a flexible portion of the toothbrush head. As pressure is applied by the user to the toothbrush handle, the flexible portion of the toothbrush head underlying the finger moves. Because the ribs are physically attached to the flexible portion of the head, the movement of the head is translated to the fingers in a manner which causes the fingers to move laterally to the longitudinal axis of the head. This movement of the fingers wipes across teeth thereby providing extra cleaning of the teeth. The movement of the fingers closest to the gumline acts to massage the user&#39;s gums. 
   The “fingers” used in this invention may take a variety of shapes and materials. The entire finger can be made of elastomeric material. Alternatively, only a portion of the finger is made of elastomeric material with the tip facing away from the head comprised of bristles extending from the elastomeric material. Preferably the elastomeric material should extend far enough up the finger height to facilitate attachment of enough rib material to promote movement of the finger in the manner described herein. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side elevational overview of a toothbrush broken along its length having a flexible head with fingers mounted thereon, showing the ribs interconnecting the finger and flexible head. 
       FIG. 2  is a fragmental front plan view showing an arrangement of fingers connected by ribs to a flexible head. 
       FIG. 3  is a fragmental plan view of single finger connected by ribs to an unflexed toothbrush head. 
       FIGS. 4 and 5  are fragmental plan views of a single finger connected by ribs to a flexible head in flexed positions caused by movement of the flexible head. 
       FIG. 6-8  are fragmental plan views of multiple fingers interconnected to each other and to a flexible toothbrush head by ribs forming a web between the fingers. 
       FIG. 9  is a fragmental cross-sectional view in elevation of the fingers mounted in a flexible toothbrush head. 
       FIGS. 10-12  are fragmental elevational views of the fingers used with the toothbrush of the invention. 
       FIG. 13  is a side elevational view of a power toothbrush using a flexible head and gum stimulation fingers. 
       FIGS. 14 and 15  are cross sectional views of the fingers with ribs interconnecting the fingers to a flexible portion of the toothbrush head. 
   

   DETAILED DESCRIPTION OF INVENTION 
     FIGS. 1 and 2  illustrate a toothbrush  10  with a handle  12  and head  14 . Mounted on or in head  14  are fingers  16 , preferably having a tapered shape. As shown in  FIG. 2  fingers  16  are preferably arranged about the periphery of head  14 . That location materially assists the gum massaging effect of the finger movement contemplated by this invention. More particularly, when the longitudinal axis of toothbrush  10  is perpendicular to the axis of teeth being brushed, as is typical with most users, the fingers  16  are closest to the gumline. 
   The fingers  16  are preferably flexible and soft to the touch. Accordingly they may be formed of a soft elastomeric material. The general shape of fingers  16  is illustrated in  FIGS. 10-12 . As so illustrated they are tapered and comprise all elastomeric material ( FIG. 10 ) or a set of bristles  18  partially surrounded by elastomeric material  20  ( FIGS. 11 and 12 ). The elastomeric material should extend along the length of finger  16  a sufficient distance to facilitate attachment of ribs as described in more detail below. 
   To facilitate the therapeutic movement of fingers  16  it is important that head  14  of toothbrush  10  be flexible and that. fingers  16  be flexibly mounted in head  14 .  FIG. 9  illustrates one form of flexible mounting of fingers in head  14 . In this embodiment the head  14  has a box-like shape in cross section. At least the upper face  22  of head  14 , and preferably the entirety of head  14 , is made of a flexible material so that the axes of fingers  16  can move relative to the plane of toothbrush  10 . The fingers  16  project from apertures  26  in the flexible upper face  22  of head  14 . Any rib and finger  16  arrangement shown in  FIGS. 6-8  can be molded into the toothbrush head  14 . This flexible mounting in a flexible portion  22  of head  14  assists in obtaining the desired lateral movement of fingers relative to the axes of toothbrush  10 . The role of ribs in obtaining that movement is explained below. 
   Another means of imparting movement to the fingers  16  is illustrated in  FIGS. 14 and 15 . As illustrated, fingers  16  are physically linked to a flexible face  22 A of head  14  by angled rib  24 . Rib  24  can be integrally molded into head  14  and finger  16  during the manufacture of toothbrush  10 . It can also be formed of a more rigid (than elastomeric) material such as polypropylene in order to enhance lateral movement of fingers  16 . Flexible face  22 A of head  14  in this embodiment can be molded around frame members  26  forming the outer periphery of head  14 . These frame members  26  of head  14  may be attached to handle  12  of toothbrush  10  in a known manner. 
   The role of ribs  24  and flexible head  14  in imparting lateral movement to fingers  16  is illustrated in  FIGS. 2-5 .  FIG. 2  illustrates the location of fingers  16  and ribs along outer edges of flexible face  22  of head  14 . Other groups of bristles or cleaning elements  17  are arranged inboard of fingers  16  as illustrated in  FIG. 2 . Fingers  16  on the outer edge of head  14  are closest to the gum line when the user holds the toothbrush in a normal position, i.e., with the longitudinal axis perpendicular to the axis of the user&#39;s teeth. Ribs  24  extend from the side of finger  16  to the face  22  or  22 A of flexible head  14 . These ribs can have a triangular, trapezoidal or like shape that interconnect the finger  16  to the face of flexible head  14 . This interconnection assures lateral movement of finger  16  as the face  22  or  22 A deflects outward or inward along the longitudinal axis when in use as described below. 
   The lateral movement of finger  16  is illustrated in the sequence shown in  FIGS. 3-5 . In  FIG. 3  there is no deflection of face  22  or  22 A of flexible head  14 .  FIG. 4  represents a deflection of face  22  that stretches that face as shown by the arrows  23  at the edge of this fragmental view. When so stretched the ends  28  of rib  24  anchored to face  22  move away from each other. That movement exerts a lateral force on finger  16  causing it to move laterally toward the outside periphery of head  14  as indicated by the arrow  25  in  FIG. 4 . Conversely, when deflection of face  22  or  22 A of head  14  causes that face to compress, the ribs  24  push finger  16  laterally in the opposite direction as indicated by the arrow  25  in  FIG. 5 . Thus, as various forces are transmitted to flexible face  22  or  22 A of head  14  during use, that head moves in compression or expansion. That movement causes fingers  16  to move in a lateral direction thereby promoting tooth cleaning and gum stimulation. 
   Another embodiment of the invention illustrated in  FIGS. 14 and 15  shows ribs  24  oriented approximately 90 degrees to the longitudinal axis of toothbrush  10  versus approximately 45 degrees shown in  FIGS. 2-5 . In the former embodiment, movement of the flexible face  22 A in an upward direction ( FIG. 15 ) causes lateral inward movement of fingers  16  as illustrated by the arrows  27  in this Figure. Conversely, downward movement of flexible face  22 A would cause lateral movement of fingers  16  away from each other toward the outside of head  14  (not illustrated). 
   Other arrangements of ribs  24  and their attachment to fingers  16  are illustrated in  FIGS. 6-8 . As illustrated, multiple fingers  16  are interconnected by a continuous rib  24 .  FIG. 6  illustrates the interconnecting ribs  24  on one side of fingers  16 . Thus, upon deflection of flexible face  22  or  22 A of head  14  all fingers  16  move in the same direction as indicated by the arrows  29  in  FIGS. 6 and 7 . If it were desirable to have the fingers  16  move in different directions the arrangement of ribs  24  shown in  FIG. 8  can be utilized. 
   Any suitable form of cleaning elements may be used as the cleaning elements  17  in the broad practice of this invention. The term “cleaning elements” is intended to be used in a generic sense which could include conventional fiber bristles or massage elements or other forms of cleaning elements such as elastomeric fingers or walls arranged in a circular cross-sectional shape or any type of desired shape including straight portions or sinusoidal portions. 
   It is to be understood that the specific illustration of the cleaning elements is merely for exemplary purposes. The invention can be practiced with various combinations of the same or different cleaning element configurations (such as stapled or in-molded technology bristles, etc.) and/or with the same bristle or cleaning element materials (such as nylon bristles, spiral bristles, rubber bristles, etc.). Similarly, while  FIG. 2  illustrates the cleaning elements to be generally perpendicular to head  14 , some or all of the cleaning elements may be angled at various angles with respect to the outer surface of head  14 . It is thereby possible to select the combination of cleaning element configurations, materials and orientations to achieve specific intended results to deliver additional oral health benefits, like enhanced cleaning, tooth polishing, tooth whitening and/or massaging of the gums. 
     FIG. 13  illustrates a powered toothbrush  10 A containing the fingers  16  of the invention mounted on a flexible head  14  of the toothbrush. Cleaning elements  17  are preferably mounted inboard of fingers  16  as illustrated in  FIG. 2 . This embodiment includes a power driven movable disc or section  30  having cleaning elements. The movable section  30  could be oscillated rotationally such as by using the type of drive mechanism shown in U.S. Pat. No. 5,625,916, or could move in and out using the type of drive mechanism shown in U.S. Patent No. 35,941; all of the details of both patents are incorporated herein by reference thereto. Although  FIG. 13  shows movable section  30  to be at the distal end of the head, the movable section(s) could be located at any desired location on the head.