BACKGROUND OF THE INVENTION AND PRIOR ART Mouth hygiene in general and dental care in particular have become in the recent years a major issue and it has now long been realized that correct teeth brushing plays a great role in ensuring the health of the teeth and gums.

Many recommendations have been issued throughout the years concerning correct strokes during the brushing for ensuring maximal penetration of the bristles between the teeth and accordingly a variety of inventions have been made in this field providing different solutions, e. g. converting linear strokes in one direction into strokes in a perpendicular direction, converting linear strokes into rotary of the bristles etc. Other recommendations are concerned with the firmness of brushing which as it has become apparent plays a great role in mouth hygiene. Various solutions have been provided in this regard as well such as, for example, bristles of varying length distributed along the toothbrush head, bristles of different rigidity, bristle tufts supported by springy members, elastic brush heads, etc.

It is furthermore appreciated that a conventional toothbrush has typically an essentially flat head portion and the bristles are secured thereto by different means, whereby it is assumed that bristles will penetrate between the teeth by the manual manipulation of the toothbrush imparted by the user or by forming the head of the toothbrush with several bristle tuft arrays which are in some way or another movable with respect to one another so as to assume different positions during a tooth brushing performance.

Many toothbrush heads are arranged such that the bristles are of uniform length which obviates their following the contour of the jaw of a person using it.

After a short while, typically several months, the bristles deform, owing to the pressure applied thereto by the user. Other toothbrushes are arranged such that the bristles are of different length and are adapted to improve penetration into the gaps between the teeth. Nevertheless, this arrangement provides a fixed contour of the brush which not only does not fit every individual, it differs at different locations when applied to the teeth.

Amongst a large variety of patents concerned with toothbrushes, US Patent No. 5,269, 038 discloses a toothbrush which automatically provides an up/down stroking action in concert with a side-to-side stroke action as the toothbrush is manipulated in a brushing process. The brush comprises two pairs of elongated bristle-carrying pads with the pads of each pair positioned side-by-side and the pairs of end-to-end. Each pad is hinged to the pad-holding end of the brush with the hinge axis being angularly related to an elongate axis of the pad. Owing to the structure of this toothbrush, in use, the bristles are allowed to follow the contour of a tooth and to penetrate into the space between the tooth and the gums. However, this toothbrush does not provide an arrangement for following the contour of the teeth in an arced shape.

US Patent No. 5,991, 959 discloses a toothbrush in which the head has a skeleton, a resilient member mounted on at least one type of the skeleton, tuft mounts in the skeleton and/or resilient member for receiving bristles, the resilient member bristle tuft being capable of toggling movement, the resilient member tuft mounts having an array of rigid receptacles or wells attached to the skeleton by a bridge hinge, characterized in that the bridge hinges are broken. A toothbrush in accordance with this patent has the advantage of the head being repeatedly and resiliently movable in a multidirectional manner to provide more effective cleaning.

However, this patent does not suggest an arrangement where the toothbrush head dynamically assumes the contour of the teeth.

A different arrangement is disclosed in US Patent No. 5,881, 426 wherein a brush is fitted with flexible bristles in which each bristle includes a flexion integral with the bristle to provide resilience to the bristle for flexing it along its longitudinal axis. The brush includes a perforated brush head for passing the bristles so as to maintain the bristles on their axis. This arrangement has a significant drawback in that it is quite likely that after a short while toothbrush and other dirt accumulates under the brush head and prevents the normal functioning of the brush. Furthermore, the axial extent of displacement is significantly restricted.

US Patent No. 5,839, 149 discloses a toothbrush wherein the brush head comprises a flexible member formed with a bristle support portion and adapted for resilient flexure and is caused to change its shape between a flat position and a deformed position in which side arrays of bristles tufts incline towards a central array of bristle tufts. The flexible member is deformable along an axis which is coaxial with elongate axis of the toothbrush handle and thus does not provide for the bristle tufts to follow the arc shape of the teeth of a user during a brushing process.

US Patent No. 5,774, 923 discloses still another toothbrush fitted with a flexibly linked zone at its head whereby a longitudinal axis of a head portion may intersect with a longitudinal axis of the handle of the toothbrush, though remaining in the same plane.

US Patent No. 2,819, 482 discloses a toothbrush wherein the head portion is formed with a resilient body mounted on a handle of the toothbrush and wherein a plurality of tuft arrays extend from the handle portion, through the resilient member and project out from the resilient member. This arrangement is useful in particular for massaging the mouth whilst on the other hand it constrains the bristle tufts and prevents them from deforming in any direction.

It is an object of the present invention to provide an improved and novel toothbrush for in the bristles mounted on the head portion assume the shape of the teeth and wherein the bristles penetrate into inter-teeth space, thereby ensuring improved contact of the bristles with the teeth and gum contour.

SUMMARY OF THE INVENTION The object of the present invention is to provide a toothbrush wherein the tuft arrays are mounted on a flexible bed having increased resiliency whereby it may be significantly elongated. The toothbrush head is devoid of any moving parts and, by one particular embodiment, the resilient member is molded to a support frame of the brush head without any additional components.

This arrangement renders the brush head a trampoline-like behavior whereby the bristles continuously displace along their longitudinal axis such that an optimal tooth brushing process takes place with essentially continuous contact with the surface of the teeth during a brushing process, ensuring improved penetration into the inter-teeth gaps.

In accordance with the present invention there is provided a toothbrush comprising an elongate handle fitted at one end thereof with a brush head, said brush head comprising a support frame accommodating a resilient bed fitted with a plurality of fixed bristle tufts; said bed being elastically deformable in a direction essentially parallel to an axis of the bristles.

By one particular embodiment the bristle tufts are molded into the bed and wherein the resilient bed is molded into the support frame.

The arrangement in accordance with the present invention is such that when a body applies axial force on the bristles, the support bed deforms so as to allow the bristles to assume a contour of said body. However, the support bed spontaneously returns to its initial shape upon cease of the axial force on the bristles.

By one particular design, the resilient bed is embedded within the support frame whereby periphery edges thereof are fixed to the support frame.

According to another aspect of the present invention there is provided a toothbrush for mounting on a toothbrush handle, said head comprising a fitting for articulating it to the handle, and having opposed top and bottom surfaces, which bristles projecting from said top surface, and a bristle bed made of an essentially resilient material and fixedly holding a plurality of bristle tufts, said support bed being deformable in a direction perpendicular to a longitudinal axis of the bristles.

BRIEF DESCRIPTION OF THE DRAWINGS In order to understand the invention and to see how it may be carried out in practice, an embodiment of the invention will now be described, by way of a non-limiting example only, with reference to the accompanying drawings, in which: Fig. 1 is an overall isometric view of a toothbrush in accordance with the present invention; Fig. 2 is a portion of the toothbrush head illustrating a support frame, the bristle carrying member and the bristles being removed ; Fig. 3 is an isometric, sectional view taken along line III-III in Fig. 1; Fig. 4 illustrates the toothbrush of the present invention at a side elevation, during a toothbrush process, applied to the teeth of an individual; Fig. 5A is an isometric view of a support frame in accordance with an embodiment of the invention; Fig. 5B is a section taken along line V-V in Fig. 5A ; and Fig. 5C is a section taken along line V-V in Fig. SA showing also a bristle support bed fitted with bristle tufts.

DETAILED DESCRIPTION OF THE INVENTION Fig. 1 illustrates a toothbrush in accordance with the present invention generally designated 20 comprising an elongate handle designated 22 and extending between a proximal end 24 and a distal end 26, and a brush head designated 30 integrally extending from said handle. Brush head 30 comprises a support frame 36 made of a rigid material and in the present example constitutes an integral extension of the handle 22. However, in accordance with an embodiment of the invention (not shown) head 30 may be removably connected to a handle of a toothbrush, e. g. an electric toothbrush in which case the frame 36 comprises suitable engagement means for coupling with a corresponding engagement arrangement of the handle.

As can best be seen in Fig. 2, support frame 36 is a two-layer hollow structure comprising a top member 38 and a bottom member 40, said top member having an upper surface 42. The top member 38 and the bottom member 40 are reinforced by integral supports 44 and 46 with a gap 48 extending between the two members and a central cavity 50 defined within said support frame 36.

As seen in Figs. 1 and 2, received within cavity 50 there is a bristle support bed 60 made of an elastically deformable material such as, for example, silicon rubber or other synthetic rubber having a significant elongation coefficient, e. g. of about 600% or so. In the present embodiment the bristle support bed 60 is molded within the cavity 50 and projects into the gaps 48 between the top member 38 and the bottom member 40 whereby it becomes secured at its perimeter to the support frame 36. Suitable gripping members 64 (Fig. 2) may be provided for increasing the support of the perimeter of the bristle support bed 60 within the frame 36.

As seen in Figs. 1 and 3, the bristle support bed 60 is essentially flush with the upper surface 42 of the top member 38 with a plurality of bristle tufts 66 upwardly projecting therefrom. In the present example, the bristle support bed is flush also at its bottom surface 65 with the lower surface 43 of the bottom member 40 (Fig. 3).

A person versed in the art will appreciate that the bristle tufts may be arranged at a variety of arrays, as known per se, and may also have different rigidity, different lengths, etc.

The arrangement of the toothbrush in accordance with the present invention is such that the bristle support bed 60 is significantly deformable in a direction essentially parallel to the longitudinal axis of bristle tufts 66 whereby depressing the bristles against the teeth 70 of an individual entails significant deformation of the bristle support bed 60 in a direction essentially parallel to a longitudinal axis of the bristles 66, whereby the free ends of the bristles assume the contour of the teeth 70 or of the gums, respectively, and whereby the bristles penetrate into the inter-teeth interstices for improved performances. As the brush displaces along the

jaw, the bristles continuously assume the respective shape, owing to high elasticity of the bristle support bed.

In the embodiment of Fig. 4 the bristle support bed 60 is illustrated in its defonned state where it extends beyond the lower surface 43 of the bottom member 40. It seen, the bottom surface of the support bed 60 assumes an undulating shape conforming essentially with the shape of the theath/gums.

Turning now to Figs. 5A to 5C, there is illustrated another embodiment of the invention wherein the support frame designated 76 comprises a top member 78 having an upper surface 80 and a bottom member 82 having a lower surface 84.

The main differences as compared with the previous embodiment is that the top member 78 is narrower and on that account the bottom member 82 is wider and furthermore, the bottom member 82 is formed with a bottom cover plate 86, which may be integrally formed therewith or attached thereto, e. g. by adhering or welding, etc.

As can be seen in Fig. 5C, the bristle support bed 90 is essentially flush with the upper surface 80 of the top member 78 and is supported at its perimeter as explained in connection with the previous embodiment, to the frame 76, leaving a deformation space 94 whereby, when the bristle support member 90 deforms it does not project beyond the lower surface 84 of the bottom member 82.

It is to be appreciated that the bristle support bed may be molded within the support frame or otherwise adhered thereto in a manner which provides peripheral support to the bristle support member whereby it will not disengage from the support frame as it deforms. Furthermore, it is advantageous that the bristle support bed is hermetically supported by the support frame whereby no liquids and dirt can enter and accumulate in the toothbrush head.