Abstract:
The invention relates to a toothbrush comprising an elongate body having one end forming a head for mounting bristles, and an opposite end forming an elongate handle. In accordance with the invention, the head includes, over at least a fraction of its periphery, a flexible portion for protecting the gums of a user against impacts.

Description:
[0001]     The present invention relates to a toothbrush of the type commonly used for cleaning human or animal teeth.  
         [0002]     More precisely, the invention relates to a toothbrush comprising an elongate body having a head for mounting bristles at one end, and an elongate handle at an opposite end.  
       BACKGROUND OF THE INVENTION  
       [0003]     A very large number of toothbrushes are already in existence, and numerous improvements have already been made thereto, both concerning the shape or the anchoring of bristles in the head, and concerning the ergonomic shape for the elongate handle. Thus, there presently exist more than two thousand patents filed in the field of toothbrushes.  
         [0004]     A toothbrush conventionally comprises an elongate body having one end that forms a mount for bristles. The body comprises a handle with a head at one thereof. The head is generally flat in shape, having a face in which bristles are implanted, and a peripheral edge. The body is generally made of a relatively rigid plastics material so that the user holding the toothbrush by the handle can press the bristles of the brush against the teeth while exerting sufficient pressure to brush the teeth effectively.  
         [0005]     Attention has already been paid to the question of protecting the gums, to ensure that they are not injured while the teeth are being brushed. Proposals have thus been made to provide toothbrushes of hardness adapted to match the sensitivity of a user&#39;s gums. A user having sensitive gums will thus prefer to use a toothbrush having flexible bristles so that the bristles rubbing against the gums do not graze them.  
         [0006]     Nevertheless, the Applicant has found that injuries to the gums are due not solely to the bristles, but also to the head of a toothbrush. Even though the peripheral edge of the head is rounded so as to avoid presenting projecting edges that might graze the gums, it can happen that the peripheral edge of the head can strike the gum hard and graze it in the event of the user accidentally moving jerkily while brushing the teeth. This type of incident is particularly widespread among people having sensitive gums, and in particular among children having their teeth brushed by an adult not sufficiently skilled in handling the toothbrush.  
       OBJECT OF THE INVENTION  
       [0007]     An object of the invention is to devise a toothbrush that provides effective protection to the gums of the user, while remaining simple in design and inexpensive to manufacture.  
       GENERAL DEFINITION OF THE INVENTION  
       [0008]     In accordance with the invention, the above problem is solved by a toothbrush comprising an elongate body having one end forming a head for mounting bristles and an opposite end forming an elongate handle, wherein the head includes, over at least a fraction of its periphery, a flexible portion for protecting the gums of the user against impacts.  
         [0009]     Thus, because of the flexible portion of the head of the toothbrush, it is possible to provide bristles of considerable stiffness, i.e. suitable for effective brushing, insofar as any jerky movement by the user during brushing can lead only to softened contact of the flexible portion against the gum, thus without any risk of bruising or grazing the gum.  
         [0010]     In a particular embodiment, the head comprises a rigid support portion surrounded, over at least a fraction of its periphery, by a fitted flexible portion which is secured to said support portion.  
         [0011]     Provision can then be made for the fitted flexible portion to be made in the form of a fender having a rounded outside edge, said fender being secured to the rigid support portion by a permanent, non-separable connection, or in a variant for the rigid support portion to present a peripheral rib integral therewith, the fitted flexible portion then being made in the form of a fender presenting, over its entire length, a groove complementary to the peripheral rib, said fender being secured to said rigid support portion by snap-fastening. In which case, the fender is advantageously secured to the peripheral rib by snap-fastening in releasable manner so that said fender constitutes a part that is interchangeable.  
         [0012]     In another embodiment, the head comprises a rigid support portion having a peripheral zone that is treated locally in order to be made flexible, thereby constituting the flexible protective portion. In particular, the localized treatment is selected from: heat treatment; adding a softening additive; and treatment by radiation, in particular ultraviolet radiation.  
         [0013]     In yet another embodiment of the invention, the head comprises a support portion of flexible material presenting a peripheral rim integral therewith and forming the flexible protective portion, said peripheral rim defining a central cavity receiving a rigid plate in which the bristles are anchored.  
         [0014]     Provision can then be made for the rigid plate to be mechanically secured in the associated central cavity of the support portion, in particular by adhesive or snap-fastening, or in a variant for the rigid plate to be secured to the support portion by constituting an insert while the support portion is being molded.  
         [0015]     Other characteristics and advantages of the invention appear more clearly in the light of the following description and the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]     Reference is made to the figures of the accompanying drawings, in which:  
         [0017]      FIG. 1  is a perspective view of a toothbrush constituting a first embodiment of the invention;  
         [0018]      FIG. 2  is a fragmentary section view on a longitudinal midplane P of  FIG. 1 , showing a toothbrush head of this first embodiment;  
         [0019]      FIG. 3  is a section view analogous to that of  FIG. 2 , for a toothbrush head in a second embodiment of the invention;  
         [0020]      FIG. 4  is a fragmentary exploded perspective view of a toothbrush constituting a third embodiment of the invention;  
         [0021]      FIG. 5  is a section view showing a variant of the  FIG. 4  arrangement, in which the support portion is overmolded on a plate in which the bristles are anchored; and  
         [0022]      FIG. 6  shows a fourth embodiment of the invention. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0023]     With reference to the Figures, the toothbrush of the invention is referenced  1 . It comprises an elongate handle  10  made of an essentially rigid material, and a head referenced  2  which is secured to one end of the handle  10 .  
         [0024]     In accordance with an essential characteristic of the invention, the head  2  of the toothbrush comprises, over at least a fraction of its periphery, a flexible portion for protecting the gum of the user against impacts.  
         [0025]      FIGS. 1 and 2  show a first embodiment of such a toothbrush.  
         [0026]     Specifically, the head  2  comprises a support portion  3  having bristles  4 , e.g. made of Nylon®, implanted in one face thereof, and a flexible peripheral portion  5 . 1  surrounding the support portion  3 . Thus, the rigid support portion  3  is surrounded over at a least a fraction of its periphery by a fitted flexible portion  5 . 1  which is secured to said support portion. Specifically, the fitted flexible portion  5 . 1  is made in the form of a fender having a rounded outside edge, said fender being secured to the support portion  3  by a permanent non-separable connection, e.g. by adhesive, heat-sealing, overmolding, or any other equivalent means.  
         [0027]     In the embodiment of  FIGS. 1 and 2 , the entire periphery of the support portion  3  is surrounded by the flexible fender  5 . 1 . Nevertheless, in a variant, provision could be made for only a fraction of the periphery to be concerned by the flexible fender  5 . 1 , in which case it will be appropriate to ensure that the flexible fender is provided at least on the distal end of the head  2 . It is this end which leads most often to impacts against the gum.  
         [0028]     The flexible fender  5 . 1  is made of any food-grade flexible material suitable for the application concerned, such as a suitable plastics material, rubber, foam, or the like.  
         [0029]      FIG. 3  shows a variant in which the head  2  comprises a rigid support portion  3  with a peripheral zone  5 . 2  subjected to local treatment in order to make it flexible, thereby constituting the protective flexible portion. Under such circumstances, the support portion  3  and the flexible portion  5 . 2  are made as a single piece of the same material such as a hard plastics material. The flexibility of the corresponding zone of the peripheral portion is then obtained by applying localized treatment to said zone, which treatment is represented diagrammatically in the figure by dots. This localized treatment may be performed by applying heat treatment to the zone in question, in particular in this case the distal end zone of the head  2 , or by adding a softening additive, or indeed by using radiation, in particular ultraviolet radiation. Other suitable treatments could naturally be envisaged.  
         [0030]     In a variant, it is possible to start conversely with a head made of flexible material that is hardened locally by treatment analogous to the above-described treatment in order to form the support portion  3 .  
         [0031]     With reference to  FIG. 4 , the toothbrush constituting the third embodiment comprises a head  2  in which the support portion  3  is made of a flexible material, and presents a peripheral rim  5 . 3  which is integral therewith. This peripheral rim  5 . 3  then forms the flexible protective portion.  
         [0032]     The peripheral rim  5 . 3  also defines a central cavity  7  that receives a set of bristles, in particular a rigid plate  6  in which said bristles  4  are anchored. The rigid plate  6  can be mechanically secured in the associated central cavity  7  of the support  3  by any other appropriate means such as adhesive or snap-fastening. When it is secured in releasable manner, that makes it possible in particular to replace the subassembly constituted by the plate  6  with the bristles  4 . Under such circumstances, it should be observed that the plate  6  should be made of a material that is essentially rigid, since given that the material constituting the support portion is flexible, it is necessary to preserve a degree of rigidity for the head of the toothbrush.  
         [0033]      FIG. 5  shows a variant in which the rigid plate  6  is secured to the support portion  3  by constituting an insert while the support portion is being molded. Under such circumstances, the plate  6  is associated with the support portion  3  by a connection that is not separable.  
         [0034]      FIG. 6  shows another variant of the invention reminiscent of the approach of the embodiment of  FIGS. 1 and 2 .  
         [0035]     In this case, the support portion  3 , which is made of a suitable rigid material, presents a peripheral rib  9  which is integral therewith. The fitted flexible portion, referenced  5 . 4 , is then made in the form of a fender that presents a groove  8  that is complementary to the peripheral rib  9  and that extends along its entire length. The fender  5 . 4  constituting the flexible portion for protecting the gum is then secured by being snap-fastened directly onto the peripheral rib  9  of the rigid support portion  3 .  
         [0036]     Preferably, a fender  5 . 4  that is secured to the peripheral rib  9  by snap-fastening is made to be removable so that said fender constitutes a part that is interchangeable. It is thus possible to put on sale a flexible fender for protecting the gums against impacts for the purpose of being fitted to toothbrushes that are not initially provided with a flexible peripheral portion.  
         [0037]     The invention is not limited to the embodiments described above, but on the contrary covers any variant using equivalent means to reproduce the essential characteristics specified above.  
         [0038]     In particular, the invention is not limited to any particular component materials for the flexible portion for protecting the gums, and it is possible to use any other suitable material, for example a material presenting characteristics of transparency or of luminosity for fancy toothbrushes.