Abstract:
A toothbrush and method of manufacture thereof is provided wherein the toothbrush has a neck, which is angled and longitudinally flexible with respect to the head and the handle. The flexible nature of the toothbrush is especially beneficial when used by wearers of various orthodontic devices such as braces

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates generally to toothbrushes, and specifically to toothbrushes for use by wearers of various orthodontic devices such as braces.  
           [0002]    Considerable difficulty has been encountered by wearers of orthodontic devices in keeping the teeth clean and free from plaque by brushing with conventional toothbrushes. It is difficult to apply enough pressure to overcome the impeding effect of the braces without injuring the gums and to obtain thorough access to all of the exposed tooth surfaces with the conventional toothbrush bristles. Sufficient pressure must be applied to the bristles so as to reach behind the brace elements. Furthermore, the presence of braces require a back and forth brushing motion which creates undue pressure, thus tending to result in pyorrhea. A toothbrush which meets the above-noted challenges is shown and described in Pavone, et al., U.S. Pat. No. 5,325,560.  
           [0003]    Pavone, et al. brings forth a toothbrush containing an elongated handle, a neck and a head having a bristle design and pattern which promotes effective brushing of the teeth while minimizing damage to the gums and allows for effective brushing action on all of the tooth surfaces despite the presence of orthodontic devices. The Pavone, et al. toothbrush bristles are designed so that the outermost rows are relatively soft and of long length, the bristles in the pattern gradually shortening in length and becoming stiffer, with the shortest and stiffest bristles being positioned along the center rows of the brush&#39;s longitudinal centerline axis. Also, the center rows of bristles are formed to be angled at their ends to reduce the pressure required to deflect the bristles beneath the brace elements thus reducing undue pressure against the gums. Furthermore, a flexible member compressibly supports the center rows of bristles. This reduced pressure avoids the tendency to develop pyorrhea disease.  
           [0004]    The Pavone, et al. toothbrush also includes an outer bumper protectively surrounding the toothbrush head and a lower tuft of bristles projecting from the lower portion of the handle. Therefore, the Pavone, et al. toothbrush protects the user&#39;s gums but also protects the orthodontic devices.  
         SUMMARY OF THE INVENTION  
         [0005]    The present invention provides an improvement to the Pavone, et al. toothbrush wherein the toothbrush has a neck which is angled and longitudinally flexible with respect to the head and the handle. The toothbrush of the present invention can be utilized with conventional toothbrushes or to maximize its value it can be utilized as a toothbrush made along the lines of that disclosed in the aforementioned Pavone, et al. patent.  
           [0006]    The above and other noted features of the present invention are further explained by a review of the accompanying detailed description and accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]    The objects an d features of the invention will become apparent from a reading of a detailed description taken in conjunction with the drawings, in which:  
         [0008]    [0008]FIG. 1 depicts the toothbrush of the present invention in relation to an orthodontic device and tooth;  
         [0009]    [0009]FIG. 2 is a side perspective view showing the preferred embodiment of a toothbrush arranged in accordance with the principles of the invention;  
         [0010]    [0010]FIG. 3 is a side view of the embodiment of FIG. 2;  
         [0011]    [0011]FIG. 4 is a fragmentary view of the toothbrush head taken from FIG. 2 showing a first embodiment flexible member;  
         [0012]    [0012]FIG. 5 is a sectional view of the embodiment taken along line  5 — 5  of FIG. 4;  
         [0013]    [0013]FIG. 6 is a fragmentary view of the toothbrush head taken from FIG. 2, showing an alternative embodiment flexible member;  
         [0014]    [0014]FIG. 7 is a sectional view of the alternative embodiment taken along line  7 - 7  of FIG. 6; and  
         [0015]    [0015]FIG. 8 is a sectional view of a third embodiment flexible member also taken along line  7 — 7  of FIG. 6.  
         [0016]    [0016]FIG. 9 is a side elevational view of a toothbrush made according to the present invention.  
         [0017]    [0017]FIG. 10 is a partial enlarged side elevational view of a toothbrush according to the present invention in an alternate preferred embodiment illustrating a portion of the handle, the neck and the head.  
         [0018]    [0018]FIG. 11 is a top elevational view of the toothbrush shown in FIG. 10.  
         [0019]    [0019]FIG. 12 is a view similar to that of FIG. 10 of an alternate preferred embodiment toothbrush according to the present invention.  
         [0020]    [0020]FIG. 13 is a top elevational view of the toothbrush shown in FIG. 12.  
         [0021]    [0021]FIG. 14 is a view similar to that of FIG. 10, being a sectional view of still another alternate preferred embodiment toothbrush according to the present invention.  
         [0022]    [0022]FIGS. 15 and 16 are sectional views illustrating the operation of fabricating a toothbrush as shown in FIG. 14 with certain items being distorted for purposes of illustration.  
         [0023]    [0023]FIG. 17 is a view similar to that of FIG. 15 illustrating fabrication operation for manufacturing a toothbrush as shown in FIG. 9 with certain items being distorted for purposes of illustration. 
     
    
     DETAILED DESCRIPTION  
       [0024]    FIGS.  2 - 5  show a toothbrush  10  arranged in accordance with the principles of the Pavone, et al. patent. The toothbrush  10  is used primarily for brushing teeth  11  with orthodontic devices such as braces  12 ; this is shown in FIG. 1. Referring to FIG. 2, the toothbrush  10  consists of an elongated handle  13 , a neck portion  14 , and a head  15  positioned thereabove. The head  15  and the neck  14  are preferably angled inward from the handle  13 . This allows for easy access to the inside of the teeth  11 .  
         [0025]    As can be seen in FIGS.  3 - 5 , the head  15  has an inside surface  22  and an outside surface  20 , both of which are peripherally surrounded and connected by a sidewall  24 . The toothbrush  10  is preferably molded from a polymeric material. Tufts  16  containing a plurality of bristles  18  are molded within the head  15  and project outwardly from the inside surface  22 . The bristles  18  are preferably of a nylon material. The tufts  16  of bristles  18  are arranged in a series of rows, thus forming a pattern upon the inside surface  22 . The length of the individual bristles  18  gradually vary from a maximum at the outermost rows  18   a  to a minimum length at the medial rows  18   b  centrally located therein. Coincidentally, the bristle  18  stiffness is selected to be at a minimum at the outermost rows  18   a  and gradually increase in stiffness to a maximum toward the center rows  18   b . The outer bristles  18   a  contact with the tooth surface  11  above and below the orthodontic device  12 , as well as penetrate the spaces between these devices  12 . The shorter and stiffer bristles  18   b  may become forced into relatively firm pressure against the tooth surfaces overlain by these braces  12 . As depicted in FIG. 5, the central two rows of bristles  18   b  have an angled portion  19  permanently formed inward toward the longitudinal axis or centerline of the toothbrush  10 . The base of these central bristles  18   b  extends perpendicularly from a plane normal to the inside surface  22  of the toothbrush head  15  and the inwardly angled portion  19  begins at a point at least halfway up the bristle. This configuration makes it much easier to deflect the tips of the bristles  18   b  beneath the brace elements  12  by the application of relatively moderate pressure against the tooth surface  11 .  
         [0026]    The outermost bristles  18   a  are mounted perpendicular to a plane  23  (FIG. 3) substantially parallel to the inside head surface  22  and are not angled outward as has been shown in various other patents such as: U.S. Pat. No. 2,797,424, “Toothbrush”, to Olson; U.S. Pat. No. 1,901,646, “Toothbrush”, to Hicks; U.S. Pat. No. 1,642,465, “Tooth And Massage Brush”, to Sheetz; U.S. Pat. No. 890,143, “Brush For Cleaning Artificial Sets of Teeth”, to Kuzzer; French No. 1,100,290 to Guzman; and, French 1,057,279 to Grignon. An end plane  50  created by the ends  48  of the outermost bristles is substantially parallel to the plane  23  when observed in the side view, as shown in FIG. 3.  
         [0027]    A flexible member  26  comprises a synthetic elastomeric material which retains the centrally located bristles  18   b  is preferably mounted to the inside surface  22 . Flexible member  26  is shown in FIG. 5. The flexible member  26  is comprised of a top surface  28  and a bottom surface  30 , both of which are longitudinally bordered and connected by sidewalls  32 . The ends of the flexible member  26  are open until located within the head  15 . This flexible member  26  serves to form an air pocket  34  therewithin. As can be seen in FIG. 4, this flexible member  26  contains a plurality of holes  36  within its top surface  28 . This allows the air  34  to be compressibly released when the central bristles  18   b  are compressed toward the inside surface  22  of the toothbrush head  15 .  
         [0028]    Referring to FIGS. 6 and 7, a flexible member  44  is shown. The flexible member  44  is envisioned to be a solid block of spongy material. This material may have voids or air bubbles therewithin. The flexible member  44  has a top surface  46  from which the center rows of bristles  18   b  extend. The flexible member  44  is bounded by toothbrush head inside walls  52  and is supported by an inside lower wall  51 .  
         [0029]    [0029]FIG. 8 depicts a flexible member  44  whereby a central portion of the head&#39;s outside surface  20  is removed therefrom to form an opening. Thus, a bottom surface  48  of the flexible member  44  is visible. Ledges  53  are formed around the opening and are integral with the head&#39;s outer surface  20 ; these ledges  53  serve to support the outermost portions of the flexible member  44  when the flexible member  44  is compressed. Additionally, a transparent polymeric material can be inserted into this central opening to form a transparent window  54 .  
         [0030]    As is shown in FIGS. 4 and 5, the toothbrush also incorporates a bumper  38  comprising a synthetic elastomeric material which encapsulates a portion of the toothbrush head  15 . The bumper  38  preferably has a cross sectional U-shape with a center portion  40  therein, and having outboard return flange portions  42  thereupon. The center portion  40  is attached to the side wall  24  and the bumper return flanges  42  are attached to the outermost edges of the inside surface  22  and the outside surface  20 . The bumper  38  serves to protect the orthodontic devices  12  during normal brushing of the teeth.  
         [0031]    Referring to FIGS. 2 and 3, another feature of the toothbrush encompasses a lower bristle tuft  46  molded within the lower end  44  of the toothbrush handle  13 . These bristles  46  can be used to brush in tooth crevices behind the orthodontic devices  12 . The lower bristles  46  are preferably molded from the same material as the bristles  18  in the head  15 .  
         [0032]    Referring to FIG. 9, a toothbrush  110 , according to the present invention has a head  115 . The head  115  may be identical to the aforementioned head  15  or can be a head of a conventional toothbrush. The head  115  is generally rigid in its longitudinal direction of extension. The head  115  has bristles  148  which extend in a generally downward direction as shown in FIG. 9.  
         [0033]    The toothbrush  110  has a neck  114 . The neck is flexibly connected with the head  115  along arrows  117 . The neck  114  angularly extends from the head  115  in a direction generally opposite a direction of extension of the bristles  148 . A handle  113  is provided. The handle is connected neck  114 . The handle  113  is generally rigid in its longitudinal direction of extension. The handle  113  is longitudinally flexibly connected with the neck  114 . The handle is provided to allow a teeth cleaning user to manipulate the toothbrush  110  within their oral cavity. The neck  114  is flexible with respect to the head  113  in the longitudinal direction along arrows  119 . The toothbrush  110  will typically be connected from a polymeric material. The head  115  and the handle  113  as shown in FIG. 9 extend in planes generally parallel to one another.  
         [0034]    Referring to FIGS. 10 and 11, a toothbrush  157  is provided. Toothbrush  157  has a handle  158 . Connected to the handle  158  is a neck  160 . The neck  160  is connected to a head  162 . The neck  160  has on its upper surface  164  and its lower surface  166  a series of grooves  168 . The grooves  168  are generally transverse a direction of extension of the neck  160 . The grooves  168  add flexure to the neck  160 .  
         [0035]    Referring to FIGS. 11 and 12, a toothbrush  187  is provided. The toothbrush  187  has a handle  188  which is similar to handle  158 . The handle  188  is connected with a neck  190 . The neck  190  is connected with a head  192 . The neck  190  has a series of longitudinal grooves or cut-outs  194 . The grooves  194  may be provided in a molding operation or may be cut-out from the toothbrush after the material fabricating the toothbrush has formed a permanent set.  
         [0036]    Referring to FIG. 14, a toothbrush  207  is shown. Toothbrush  207  has a head  208 . Flexibly connected to the head  208  is a neck  210 . The toothbrush  207  has a handle  212  flexibly connected to the neck  210 . The handle  212  has a stiffener  214 . The stiffener  214  can be made from a generally rigid solid or hollow member which is fabricated from a polymeric material, wood or other cellulosic materials. In a similar fashion, the neck has a stiffener  216  and the head has a stiffener  218 . The stiffeners are encased in a polymeric material  220  which not only provides an outer form for the toothbrush  207  but also performs an adhesive function of connecting the stiffeners  212 ,  216  and  218  together. The polymeric material  220  can be a nature or synthetic elastomeric material. Depending upon the properties of the material  220 , and exterior of the toothbrush  207  can be covered with a thin sheet of plastic material  222  which is selected to give color and finish qualities which are most desirable.  
         [0037]    Referring to FIGS. 15 and 16, a molding process for fabricating a toothbrush  207  is shown. A mold  229  is provided having an upper half  230  and a lower half  232 . The mold has an upper injector  234  which is fitted material from a tank  236  containing plastic material  222 . The injector  234  is also associated with a blower  238  utilized for injecting pressurized air into the mold cavity  240  when the mold halves are closed (FIG. 16). Stiffeners  214 ,  216  and  218  are placed within the mold chamber and are positioned by appropriate fixtures  242 . Upon closure of the mold halves  230  and  232  together, plastic material  222  will be inserted into the mold cavity  240  by the injector  234 . Injector  234  will also deliver pressurized air provided by blower  238  into the mold chamber  240  causing the plastic material  222  to form a lining or outer coating for the toothbrush. After an appropriate cure period, wherein after the molds halves  230  and  232  can be appropriately heated or cooled, an injector  244  will inject into the mold the plastic material  220  which is held in a tank  246 . Again, after an appropriate cure time, the toothbrush head  208 , neck  210  and handle  207  will be formed and then removed from the mold halves  230 ,  232  which are then separated from one another.  
         [0038]    Referring to FIG. 17, a mold  330  is provided to form a tooth brush which is fabricated from two polymeric materials having varying flexure modulus. The first plastic material  332  which is generally rigid is contained within a tank  334 . Tank  334  is connected by a line  336  with a toothbrush handle injector  338 . Tank  334  is connected with a line  340  which is also connected with a head injector  342  and neck injectors  344  and  346 . A plastic material  350  is provided in a tank  352 . Tank  352  by line  354  is connected with an injector  356 . Tank  352  by line  358  is connected with an injector  360 . The mold  330  has an upper half  362  and a lower half  364  which are brought together. The upper half of the mold  330  has a line  366  connected with a blower  368 . In operation the mold halves  362  and  364  are brought together forming a mold chamber  370 . A controller (not shown) is utilized to control and sequence the injectors  338 ,  346 ,  356 ,  360 ,  344 ,  342 . The controller also turns on the blower  368  to pressurize the mold cavity  370  via the line  366 . The controller will then cause the injectors  338  and  342  either simultaneously or sequentially to inject the material  332  to form a handle  113  and a head  115 . The pressurization provided by line  366  prevents the high flexure modulus material from invading the neck portion of the mold chamber  370 . The controller will also subsequently cause injectors  346 ,  356 ,  360  and  344  to form an initial blend of materials from materials  332  and  350 . Initially the blend will be mainly from the high modulus material  332 , however, subsequently the controller will cause the blend to be gradually switched to an almost 100% blend of the material  350 . The result will be that a middle portion of the neck  114  will be the most flexible with the outer portions of the neck progressively being more rigid. Since the materials  332  and  350  are both thermoplastic resins the blend will help prevent delamination between two dissimilar materials to prevent the formation of a mold interface between the materials. The toothbrush  110  can then be taken from the mold and in a different embodiment (not shown) the toothbrush  110  can be provided with an outer coating in a process similar to that aforedescribed and referenced to FIGS. 15 and 16.  
         [0039]    It will be appreciated that the toothbrush of the present invention represents a significant improvement for brushing of teeth having attached orthodontic devices. While a number of specific embodiments of this toothbrush have been disclosed, it will be appreciated that various modifications may be made to this toothbrush without departing from the present invention.