MXPA01007964A - Toothbrush head with flexibly mounted bristles - Google Patents

Abstract

The present invention relates to a toothbrush (10) having bristles mounted on a flexibly resilient lattice network, such that the bristles deflect during brushing to conform to the various arcuate surfaces of the teeth for more effective cleaning thereof.

Description

HEAD OF TOOTHBRUSH WITH FLEXIBLE MOUNTED PIGS Field of the invention The present invention relates to toothbrush heads and more particularly to toothbrush heads having bristles mounted on an elastically flexible network, such that the bristles flex to conform to the configuration of the teeth.

Background of the Invention Conventional toothbrushes comprise smooth tufts each having a first end which is held captive in and fixed to a head of the brush, and a second end which is free and which is used for brushing. The free ends of the various tufts have a wrapping surface which is capable of being slightly deformed by the bristles that are bent when they come in contact with a surface to be brushed, but which is unable to properly mate to a surface having a surface. complex form with varying levels. Such a complex surface is present in the mouth, where the teeth generally rest in a "C" curve inside the lower and upper jaw, each row of teeth consequently having a convex outer curve and a concave inner curve. In addition, the teeth themselves have an outline in an arched shape that have significantly varying levels, including an interproximal area in deep "V" shape between one tooth and the next.

The desire of the users to make the bristles conform to the teeth and to penetrate the interproximal spaces between the teeth is expressed by the forced application of the brush to adequately deform the bristles to the arched contours of the denture. Such forced application of the brush against the teeth merely leads to excessive wear of the surfaces of the teeth between the teeth to provide the desired cleaning.

Toothbrushes such as those described in patent cooperation treatise WO 98/35584, having bristle tufts capable of forward and backward movement partially describe the above problem. The patent cooperation treaty WO 98/35584 discloses the tufts of bristles mounted on a flexible material held within an arrangement of rigid wells or wells whose connection to the frame or total skeleton of the brush has been broken. While the tufts are only connected to the brush by the elastic material these will move back and forth independently or move in all planes (up / down / sideways). However, such independent movement of the bristles will not cause them to conform to the configuration of the teeth.

U.S. Patent No. 4,633,542 discloses a toothbrush in which the bristles are slidably mounted within a rigid head, which rests on a flexible deformable membrane. There is a cavity inside the head inside the toothbrush below the membrane, such that the bristles are forced flexibly on the head while the bristles are applied to the teeth. This independent movement of the bristles, in a plane, can not cause them to conform to the arched, inclined surfaces of the teeth.

Patents of the United States of America Nos. ,355,546, 5,483,722 and 5,839,149 disclose toothbrushes whose heads are formed of a rigid frame supporting a flexible elastic member which has a series of linear parallel lines or arrangements of tufts of bristles, such lines of tufts of bristles are oriented as length of the toothbrush's longitudinal axis. In each of these patents the parallel lines of bristles are flexibly mounted, such that in brushing when a tooth is forced against the center line of the tufts, that line of tufts may yield away from the tooth, causing the adjacent lines of tufts of bristles to orient themselves around the sides of the tooth. While this contouring around the tooth is in two dimensions, these patents fail to face the total three-dimensional curvature of the teeth, especially the interproximal area in the form of a deep "V" between one tooth and the next.

U.S. Patent No. 5,651,158 discloses a flexible head toothbrush having many embodiments, including a first embodiment in which the bristles may be mounted on linked head segments by means of slots or slides, e.g. , flexible which can be filled with an elastic elastomer. A second embodiment comprises a brush head having mounted segments of bristles within a hard peripheral frame, the segments are linked at flat points located at 90 ° to the longitudinal axis of the handle, the linkage is of delegated sections such that the segments can be made to oscillate around these links, in addition to flexing. A third embodiment includes a hard peripheral frame containing a toothbrush head formed on one or more flexible and elastic bristle conveyor chains linked to one another and linked to at least one end of the frame. A fourth embodiment is formed of segments which are not joined to one another, but are flexibly and elastically linked to the handle or frame, where the link to the frame may be thin sections or spines. At each incorporation of the various segments or conveyors of sows may be flexed independently or at least in coordination with the adjacent segments or conveyors of sows within the chain of conveyors of sows; such limited coordination of the orientation of the bristle tufts around the teeth will not be able to provide the conformation of the various arcuate surfaces of the tooth surfaces necessary for effective cleaning.

There is a need for a toothbrush, where the bristles coordinate their orientation to conform to the surfaces of the three-dimensional arched tooth and the interproximal area in the form of a deep "V" between one tooth and the next, so as to provide total cleanliness effective Synthesis of the Invention The present invention encompasses a toothbrush having tufts of bristles which are capable of an increased conformation to the surfaces of the arcuate teeth, said toothbrush comprises a handle having a longitudinal axis and at one end thereof a head that contains a plurality of tufts of bristles extending therefrom; such a head has a rigid periphery surrounding it with an opening extending therethrough and through which is an open net or lattice of flexible elastic spines; wherein, each bundle of bristles is anchored to said head at a node formed by the intersection of said spines. The lattice has a part which is free of spines, this part is located at the center of the head and on each side of the longitudinal axis, such that the lattice segments on each side of the longitudinal axis will be able to flex independently. Each segment of the lattice is flexed such that during brushing, while the tooth is forced against a bundle of bristles, that bunch of bristles may yield to the opening and the surrounding bristle tufts may tend to flex towards that tooth in particular, such tufts of flexing bristles that are formed around the three-dimensional, arched surfaces of the particular tooth for more effective cleaning thereof. Brief Description of the Drawings Figure 1 is a side plan view, showing the toothbrush with a typical flat bristle pattern.

Fig. 2 is a front plan view of the toothbrush showing within the head section the network of bristle tuft carriers supporting the bristles shown in Fig. 1.

Figure 3 is an enlarged front plan view of the head of the toothbrush shown in Figure 2.

Figure 4 is a sectional view, through section B-B of figure 3, showing in two dimensions the conformation of the bristles around the arched surfaces of a typical tooth.

Figure 5 is a detail of the tufts of bristles, showing the nodes within the network of the conveyors of the tufts of bristles, for example the fused ends of the tufts of bristles secured together by the connecting spines.

Figure 6 is an alternate detail of the bristle tufts as shown in Figure 5, for example the fused ends of the bristle tufts together by the spines that are connected overmolded with an elastomer.

Detailed description of the invention Referring now to the drawings, wherein the reference of similar numbers refers to the same or similar elements among the various figures, and in particular to figures 1 and 2; wherein a toothbrush 10 is shown, in accordance with the present invention. Referring specifically to Figure 2, a front flat view of such a toothbrush, 10, having a head, 18, integral with the handle, 12, extending therefrom and a longitudinal axis, A-A, therethrough. The head, 18, contains a face, 14, which has a central cavity through which is an open network or a lattice of flexible elastic bristle conveyors and which incorporate the features and construction of this invention. Shown in Figure 1, extending from the face, 14, there are rows of tufts of bristles, 16, transverse to the longitudinal axis A-A. Each bundle of bristles, 16, are embedded and supported by a node, 20, which as can be seen in Figure 3, is formed in the conjunction in which the structural elements or the dorsal spines, 22, of the network cross .

As in Figure 3, the face of the toothbrush of the present invention, 14, has a peripheral frame or a rigid periphery, 24, the rigid periphery defining an opening or opening extending through the head of the brush of teeth, 18. Alternatively, the toothbrush can also be formed with a plugging through the back of the head of the toothbrush in the form of a lower concave segment and separated from the lattice. In the case where the back of the toothbrush is enclosed, the lower concavity of the lattice can extend from 50 to 80% of the distance from the face to the rear, for example the depth of the toothbrush head, Such depth is about 1/4 of an inch. The flexing of the bristle conveyors in the concavity, during brushing, is illustrated by FIG. 4, which is a cross section B-B of FIG. 3, perpendicular to the longitudinal axis A-A of the toothbrush. Figure 4 only illustrates the conformation of the bristles around the tooth in two dimensions with the flexing of the central bristle, 26, in the direction of the arrow in figure 4. However, the flexing of the central bristle, 26, does not it can only cause the bristles perpendicular to the longitudinal axis AA to flex towards and conform to the tooth; but, also the adjacent bristles parallel to the longitudinal axis will be able to flex towards and conform around the tooth providing the present invention with the three dimensional conformity to the tooth for an effective cleaning thereof.

Furthermore, within the present invention the lattice of the dorsal spines extending across the face, 14, of the toothbrush has a central part free of said dorsal spines, such that the central dorsal spines located on the head, , and parallel to the longitudinal axis, AA, they do not cross, for example they are not connected (see figure 3). This discontinuity within the lattice allows the separate bundle that supports the segments of the lattice, on each side of the longitudinal axis, to move independently. Such independent movement of the bunch that supports the network segments makes it easier for toothbrushes to simultaneously clean different teeth and areas of the denture as it occurs during brushing.

The head, 18, comprising the neck, the peripheral frame, 24, and the grid or conveyor network of flexible elastic bristles is preferably integral with the handle of the toothbrushes, 12, for example molded or otherwise formed as a simple piece. The periphery of the head, 24, is at least 1/32 of an inch wide, preferably at least 1/16 of an inch wide, so that it is rigid enough to adequately support the conveyor network of tufts of bristles, 20, attached to it.

The network of bristle tuft transporters, including the spines, 22, and the nodes, 20, are made of an elastic, flexible material, preferably of polypropylene.

Alternatively, the spines, 22, may be made of polyethylene or thermoplastic elastomer (TPE), or a combination thereof. The degree of flexibility or elasticity of the spines, 22, can be further controlled by varying their dimensions, for example by reducing the depth or thickness of each spine, 22, to provide additional flexibility or by providing an overlay of a second elastomer around each spine, 22, and node, 20, as illustrated in Figure 6. Suitable thermoplastic elastomeric materials include a thermoplastic vulcanite (TPV) which consists of a blend of polypropylene and EPDM (monomers) of propylene ethylene diene) which is available as Sandoprene (brand), described in U.S. Patent No. 5,393,796; or Vyram (brand), another thermoplastic vulcanite consisting of a mixture of polypropylene and natural rubber, both Santoprene and Vyram are elastomers marketed by Advanced Elastomer Systems LP, Akron, Ohio 44311. Another, and preferred thermoplastic elastomer is the Dynaflex G6713 (trade mark), marketed by GLS Corp. Cary, Illinois 60013. These and other suitable elastomers typically have a Shore A hardness of from about 13 to 96, with about 29 being the preferred hardness.

Current toothbrushes are typically molded of polypropylene, in the present invention it is preferable that the netting of conveyors of bristle tufts also be of polypropylene to facilitate the molding of a toothbrush step. If a clear appearance is desired, the handle, 12, the head, 18, and in the lattice may be polyester, such as a polyethylene terephthalate. The preferred polypropylene is Huntsman Polypropylene 5520 (brand), manufactured by the Huntsman Polypropylene Corporation, Hinsdale, Illinois 60521.

If desired, the toothbrush of the present invention can be molded as a "dual component" toothbrush, by which it means that the flexible elastic material of the lattice or net supporting the bristles is of a different material than that of the head of the hard plastic toothbrush, 18, and the handle, 12. The method of manufacturing such a dual component toothbrush by conventional dual component injection molding technology is well known in the art. For example, according to the present invention, the lattice material can be introduced into the head area by a second injection step, after that used in injection molding of the head implanting the hard bristle and the handle . In this second injection step the semi-finished toothbrush is placed in a second mold in which the material of the lattice is injected around the inside of the rigid periphery, 24. To increase the surface area for the elastomer to adhere to the Rigid periphery, 24, for increased adhesion thereto, a groove or channel can be provided around the inner upper surface of the rigid periphery.

One step of the molding process can be used in the manufacture of the toothbrushes of the present invention, when the head, 18, with has an opening extending through it and when the lattice from the same material as the remainder of the frame of the toothbrush, for example the head, 18, and the handle, 12. In contrast, a two-step molding process should be used when the head, 18, the toothbrush contains a concavity below the lattice, the latter with cavity is formed by the toothbrush having a backside enclosed, such an enclosure It is separated from the lattice. In such a two-step molding process, the toothbrush framework and the integral lattice are formed in a first injection mold and the semi-finished toothbrush is relocated in a second injection mold, wherein the back box is formed.

The ease of the two step injection molding of the toothbrushes of the present invention can be by the use of a two component mold. The two component molds are available from Machines Boucherie N.V. , Izegem, Belgium; such molds can be assembled in typical injection molding machines for such implementation of the two-step injection process, such machines include 300-ton two-component injection molding machines available from Engel Canada, Inc., Guelph, Ontario.

The bristles of the toothbrush can be implanted while the nodes of the flexible elastic elastomeric material of the net supporting the bristles are formed using non-basic in-mold (IMT) tuft technology as described in the US Pat. America Nos. 5,609,890, 5,390,984, and 5,533,791. Such technology of tufts in mold involves a process and the associated machinery where each tuft of the bristles are first preformed in a set by fusing their base of bristles together with a knob. This knob is then held in the mold in which the elastic flexible material of the net or lattice that supports the bristles that are injected, such that the material flowing around the knob, anchoring the tuft in place within the face of the toothbrush, 14. Figure 5 illustrates the tufts of the tuft technology in the bristle mold, 16; wherein, the material of the net supporting the bristles, for example the spines, 22, surrounds and anchors the knob, 28, at the base of each tuft of bristles, 16.

Claims (8)

1. A toothbrush having bristle tufts capable of providing improved compliance to the surfaces of the arched teeth, comprising: a handle having a longitudinal axis and a head at one end thereof, said head contains a face having a plurality of said tufts of bristles extending therefrom; said face has a rigid periphery, within such a rigid periphery is an opening extending therethrough; a network of flexible elastic spines that form a tang that extends through said opening and fastened to said rigid periphery; said entangled having a central part which is free of said spines; said entanglement has nodes located at the intersection of said spines, each node has a tuft of bristles anchored thereto.

2. The toothbrush as claimed in clause 1, characterized in that the rigid periphery is at least 1/32 of an inch wide.

3. The toothbrush as claimed in clause 1, characterized in that the spines are made of polypropylene, polyethylene, a thermoplastic elastomer, or a combination thereof.

4. A toothbrush exhibiting increased compliance to arched tooth surfaces to increase cleanliness, comprising: a handle having a longitudinal axis and a head at one end thereof, such a head contains a face having a plurality of tufts of bristles extending therefrom; said face has a rigid periphery, to which said rigid periphery are coupled a network of flexible elastic dorsal spines forming a lattice extending through said face; said lattice has a central part which is free of said spines; said lattice has nodes located at the intersection of the spines, each node has a tuft of bristles anchored therein; said head has a concave part therein, below said lattice and extending through said head.

5. The toothbrush as claimed in clause 4, characterized in that the concave part can extend from 50 to 80% of the depth of the head of the toothbrush.

6. The toothbrush as claimed in clause 4, characterized in that the rigid periphery is at least 1/32 of an inch wide.

7. The toothbrush as claimed in clause 4, characterized in that the back spines are polypropylene, polyethylene, and a thermoplastic elastomer, or a combination thereof.

8. A process for making a toothbrush, comprising: preforming the tufts of bristles by fusing the base of a plurality of bristles into a knob; placing the knobs of said tufts of preformed bristles into a toothbrush mold; injecting the flexible elastic material around the knobs to form nodes, whereby the flexible elastic material is enclosed within it and wherein said flexible elastic material forms dorsal spines connecting said nodes in a tangled through the face of said brush of teeth; said entangled has a central part which is free of any spine.