Method for producing a toothbrush, toothbrush and device for producing a toothbrush

Abstract

The invention relates to a method for producing a toothbrush (1) that has a shape which is suitable for simultaneously cleaning a plurality of tooth surfaces, having the following steps: producing a bundle support (2) having a base (4) and at least two limbs (6), each of which is connected to the base (4) via a hinge (10) and each of which is provided with at least one bristle bundle (8), and shaping the bundle support (2) into the shape which is suitable for simultaneously cleaning a plurality of tooth surfaces by pivoting the limbs (6) in their respective hinges towards one another. The invention also relates to a device which is suitable for carrying out said method and to a toothbrush (1) produced according to said method.

Description

[0001] Method for producing a toothbrush, toothbrush and device for producing a toothbrush The present invention relates to a method for producing a toothbrush with a shape suitable for cleaning several tooth surfaces simultaneously, as well as to such a toothbrush and a device for producing such a toothbrush. In the field of tooth cleaning, efforts are known to provide a device that can clean several teeth and in particular several tooth surfaces of the teeth simultaneously and thus reduce the time required for tooth cleaning compared to the use of conventional manual toothbrushes. Many such devices are said to be able to clean the teeth of the entire jaw or even the upper and lower jaw simultaneously.WO 2018 / 014061 A1, for example, proposes a mouthpiece designed like a denture guard, comprising a carrier with cleaning elements arranged thereon, which are arranged on the carrier for simultaneous engagement with essentially all teeth of an upper jaw and / or a lower jaw of a user. However, toothbrushes known from the prior art with a shape suitable for the simultaneous cleaning of several tooth surfaces are usually of inadequate quality or difficult and complex to manufacture. It is an object of the present invention to remedy at least one of these disadvantages.To achieve this object, the present invention proposes a method for producing a toothbrush with a shape suitable for the simultaneous cleaning of several tooth surfaces, which comprises the following steps: producing a bundle carrier with a base and at least two legs, each of which is connected to the base via a hinge and each provided with at least one bundle of bristles, and reshaping the bundle carrier into the shape suitable for the simultaneous cleaning of several tooth surfaces, in particular a single tooth, by pivoting the legs in their hinge towards one another. The shape suitable for the simultaneous cleaning of several tooth surfaces is preferably a U-shape or at least a shape that enables the legs to simultaneously clean the inside of at least one tooth with one leg and the opposite outside of the tooth with the other leg.As a rule, the legs are provided on opposite sides of the base. The base can have cleaning elements for cleaning a chewing surface or an incisal edge of at least one tooth. The forming process generally leads to a plastic change in the shape of the bundle carrier. During the manufacture of the bundle carrier, the legs and preferably also the base are provided with bundles of bristles. This can be achieved by first producing a body forming the bundle carrier, which is usually made of plastic and is provided with blind holes, which are subsequently filled with bundles of bristles. The bundles of bristles are usually attached to the bundle carrier body by means of anchors.Alternatively, the bristle bundles can be provided with a thickened portion prior to production of the bundle carrier body, which is inserted into an injection mold for producing the bundle carrier body by injection molding a plastic, and is flowed around during injection molding and accordingly sealed into the solidified plastic. In addition to these two more conventional techniques for attaching the bristle bundle to the bundle carrier body, any type of attachment is conceivable within the scope of the present invention. For example, by introducing a thickened portion provided by melting at the attachment-side end of the bristle bundle into a hole or blind hole in the bundle carrier body, the diameter of which is dimensioned such that it can accommodate the thickened portion. The thickened portion usually has an extension in the cross-sectional direction of the bristle bundle that is greater than the diameter of the bristle bundle.After the thickening is introduced into the bundle carrier body, the plastic material is forced into the hole on the surface of the bundle carrier body penetrated by the bristle bundle to form a positive stop for the thickening, allowing the actual bundle to pass through; see EP 3448201 B1. The above techniques can be used as desired in the manufacture of the bundle carrier. Alternatively or additionally, the base can have a TPE cleaning element molded onto it, which interacts with the chewing surface. The bundle carrier is usually made of a hard component. This refers to a material selected from the group consisting of PP, PA, PET, ABS, PBT, and PE.The legs of the bundle carrier produced in this way, provided with bristle bundles, are pivoted towards each other so that the surfaces of the legs through which the bristle bundles extend face each other and form a receiving space between them adapted to accommodate a tooth. The adaptation can be such that the tooth fits between the use-side ends of the bristle bundles without deforming them. In this case, opposing tooth surfaces of one tooth can be brushed by a relative movement of the toothbrush essentially transversely to the row of teeth. If one or more cleaning elements and / or bristle bundles are also provided at the base, cleaning or brushing of the chewing surface of the corresponding tooth can also take place.The adaptation of the receiving space to the tooth can also be such that the tooth fits between the legs, but the distance between the usage-side ends of the bristle bundles protruding from opposite sides of the legs is less than the width of the tooth, so that the bristle bundles can permanently rest on the tooth surfaces of a single tooth on both sides. Preferably, the distance between the usage-side ends of the bristle bundles protruding from opposite sides of the legs can be adjusted, at least to a certain extent, by the user when using the toothbrush due to the articulated connection of the legs to the base. This makes it possible to adapt to the different shapes of the teeth in a row of teeth, as well as to the different individual tooth shapes of different users, and to adjust the contact force with which the usage-side ends of the bristle bundles are pressed onto the tooth surfaces.In the description, the width of the tooth is understood to be the extension transverse to the extension of the row of teeth in the dentition. The length of the tooth corresponds to its extension in the direction of the row of teeth in the dentition. It is understood that the human dentition describes a U-shape, so that the row of teeth is U-shaped in a plan view of one of the jaws in a direction orthogonal to the length and width of the teeth. According to a preferred development of the present invention, the bundle carrier is manufactured in one piece using an injection molding process, so that the injection-molded bundle carrier is finished off the tool. If part of the bundle carrier is encapsulated, it is designed as a two-component part. At least one of the hinges is injection-molded as a film hinge.The film hinge is generally formed by creating a thin section between each leg and the base compared to the adjacent sections. This can be achieved by having the injection mold for forming the bundle carrier have a projection on the surface forming a rear side of the bundle carrier at the locations that correspond to the locations of the film hinge. The thickness of the bundle carrier is understood to be an extension in a direction that runs transversely to the surface of the bundle carrier provided with bristle bundles. Accordingly, the front side of the bundle carrier has the surface of the bundle carrier provided with bristle bundles. The opposite surface of the bundle carrier therefore forms the rear side. The bristle bundles usually extend in line with the thickness of the bundle carrier.The length of the bundle carrier produced in this way is defined as the direction of the bundle carrier with its greatest extension transverse to the thickness of the bundle carrier. In the longitudinal direction of the bundle carrier, the base is provided between the legs. The width is defined as the extension of the bundle carrier in a third spatial direction that is orthogonal to the length and thickness of the bundle carrier. The base itself can be designed as a thin section that connects the two legs. In this respect, a film hinge provided by the base itself, which combines the hinges for both legs, may be sufficient. However, the base is preferably designed with a similar thickness to the legs, with a film hinge being formed between each leg and the base. The film hinges create an articulated connection between the legs and the base, which is easy to manufacture.More preferably, the leg, or at least one leg, can have one or more film hinges, whereby the legs can be applied or pressed against the tooth surfaces even more flexibly during use. According to a further preferred development of the present invention, the legs and the base are injection-molded such that they extend in the same plane. In particular, the surface of the bundle carrier, which forms the front side, extends in one plane. This allows the bristle bundles to be easily connected to the bundle carrier. In particular, the bristle bundles can be held by a holder with a flat contact surface, wherein the holder can simultaneously be used as an upper part of the injection mold for shaping the surface through which the bristle bundles penetrate.In any case, the bundle carrier can be provided with bristle bundles by arranging the attachment-side ends of the bristle bundles in one plane. According to a further preferred development of the present invention, after the legs have been pivoted, a plastic material is injection-molded onto at least one of the hinges. This allows the formed bundle carrier to be fixed in a shape suitable for the simultaneous cleaning of several tooth surfaces. By appropriately selecting the plastic material and the shape of the injection-molded plastic material, the flexibility of the hinges can be adapted to the desired requirements. These requirements can, for example, vary along the row of teeth of an individual user and, of course, also individually for each user. The plastic material can be, for example, PP, TPE, PU, ​​or silicone.It is also conceivable within the scope of the present invention that a hard component is first injection-molded, which is then over-molded with a soft component. In a secondary aspect, the present invention provides a toothbrush with a shape suitable for the simultaneous cleaning of several tooth surfaces. A toothbrush with such a shape is known, for example, from WO 2018 / 014061 A1. The toothbrush according to the present invention has a one-piece injection-molded bundle carrier with a base and at least two legs, each of which is connected to the base via a hinge and each provided with at least one bundle of bristles.As a rule, the legs extend obliquely or at a right angle from the base and form a receiving space for at least one tooth, which is dimensioned such that the inside of at least one tooth can be cleaned by one leg and the opposite outside of the tooth can be cleaned by the other leg at the same time. The surfaces of the legs through which the bristle bundles extend lie opposite each other. During use, at least one tooth is arranged between these opposite surfaces; the tooth is then located in the receiving space. The hinges can be designed as film hinges. The bundle carrier can be essentially U-shaped. The base can itself be U-shaped to replicate the U-shape of the human dentition. The base can be a rigid base whose shape extends over the entire dentition or only part of it.The base can also be divided into flexible segments. Each base segment can be connected to a neighboring base segment via a joint. This results in a toothbrush that can adapt as optimally as possible to the individual shape of the human dentition and can be used, for example, in the more curved area of ​​the front incisors or in the back area of ​​the dentition where the molars lie essentially straight one behind the other. The articulated connection of different base segments can be achieved by a film hinge or similar. Gussets or small recesses in which dirt could nest or which, due to their contours, could harm the sensitive oral mucosa, can be prevented by overmolding the base with a soft, elastic plastic.Such a covering can also be provided in the region of the articulated connection of various base segments. The toothbrush can in particular be manufactured according to the above method. Preferably, it has one or more features that result directly from the method described above. According to a preferred development, the toothbrush has at least one hinge reinforcement on each of the hinges. This can be made of plastic and injection-molded onto the hinges, i.e., formed onto the one-piece bundle carrier after it has hardened. This allows the flexibility of the hinge to be reduced, and the shape suitable for cleaning several tooth surfaces at the same time can be retained for longer. In the case of a film hinge, the hinge reinforcement usually at least partially compensates for the reduced thickness at the location of the film hinge.More preferably, the hinge reinforcements are each flush with the outer edges of the base and the outer edges of the respective leg. According to a further preferred embodiment, an outer side, which lies opposite the surfaces of the legs through which the bristle bundles extend, has a haptic design. This can be achieved, for example, by increased roughness of the outer side, knobs, or depressions. The haptic design allows the toothbrush to be gripped and moved with the thumb on the outer side of one leg and with another finger on the outer side of the other leg, like with pliers. Instead of the haptic design, or in addition to the haptic design, the toothbrush can have a generally elongated toothbrush handle, familiar from conventional toothbrushes, which serves to move the toothbrush manually. Alternatively or additionally, the toothbrush can comprise an electric drive.According to a further preferred development, two opposite sides of the base are each connected to two legs, which each form a receiving space between them for receiving at least one tooth. The number of legs per side is not limited per se by the present invention and can also vary. The legs can be arranged symmetrically or alternatively asymmetrically. According to a further preferred development, the base of the bundle carrier is provided with bundles of bristles which are intended for cleaning a chewing surface and are preferably arranged in a ring shape. According to a further preferred development, at least some and preferably all of the bundles of bristles of each leg are arranged in at least two rows provided next to one another and offset from one another. A row is understood here to be an arrangement of bundles of bristles one behind the other along the longitudinal extent of the legs.An offset results from a different position of the bristle bundles in one row in the longitudinal direction compared to the position of the bristle bundles in the other row. The bristle bundles can be contoured to adapt to the tooth shape. Contouring is understood to mean an arrangement of the use-side ends of individual filaments of a single bristle bundle in different planes. Each plane extends at right angles to the longitudinal extent of the individual filaments / bristles. Contouring can be achieved additionally or alternatively by the use-side ends of neighboring bristle bundles being in different planes. For example, the use-side ends of a single bristle bundle can lie in one plane, which, however, is different from the plane in which the use-side ends of the filaments of another bristle bundle, for example the neighboring bristle bundle, are located.Both types of contouring discussed above can be combined with one another, for example to form a cleaning-active surface formed by the usage-side ends of all filaments, which has a stepped, convex and / or concave shape, depending on which tooth shape is to be brushed or whether bristle bundles are also to reach into the interdental spaces. For this purpose, the bristle bundles can also have a few or even just a single filament. The bristle bundles can be shaped and thicknessed so that they can penetrate particularly into the interdental space. It goes without saying that the bristle bundles arranged on the leg can have filaments of identical or different diameters. The same applies to the diameter of an individual filament, for example for cleaning the interdental space.In a further subordinate product aspect, the present invention provides a toothbrush rail with a plurality of toothbrushes, which can be designed as described above and arranged in a row, so that the toothbrushes lined up next to one another form a receiving space for at least a portion of a dental arch. The row can extend, in particular, along a curved line. In a further subordinate aspect, the present invention provides a device for producing a toothbrush with a shape suitable for simultaneously cleaning multiple tooth surfaces.The device comprises a bristle and bundle carrier forming device for producing a bundle carrier with a base and at least two legs, each connected to the base via a hinge and each provided with at least one bristle bundle, and a forming device for forming the bundle carrier into a shape suitable for simultaneously cleaning several tooth surfaces, in which the legs are pivoted towards one another in their hinge. The device preferably comprises an injection molding device for encapsulating the formed bundle carrier. Further details and advantages of the present invention will become apparent from the following description of an exemplary embodiment in conjunction with the drawing.1 shows a cross-sectional view of an embodiment of a toothbrush according to the invention; Figure 2 shows a schematic view of part of a bristle and bundle carrier forming device; Figure 3 shows a schematic view of part of a forming device; and Figure 4 shows a perspective side view of a variant of a bristle bundle carrier. Figure 1 shows a cross-sectional view of a toothbrush 1 with an injection-molded bundle carrier 2, which has a base 4 and two legs 6 extending almost at right angles from the base 4, each provided with a plurality of bristle bundles 8 and each connected in one piece to the base 4 by a hinge 10 designed as a film hinge. In the exemplary embodiment, the base 4 is also provided with bristle bundles 8.The hinges 10 are each provided with a hinge reinforcement 12 made of a soft, elastic plastic material such as TPE or PU. In Figure 1, the use-side ends of the respective bristle bundles 8 are contoured. A cleaning-active surface 14 of the toothbrush 1 shown, formed by all use-side ends of the bristle bundles 8, is concave on both sides of the legs 6, corresponding to the physiological shape of a molar. The use-side ends of all bristle bundles 8 are located on different planes. This is achieved on the one hand by the bristle bundles 8.1, 8.4 at the edge of the cleaning-active surface 14 being longer than the bristle bundles 8.2, 8.3 in the middle of the cleaning-active surface 14, and on the other hand by the legs 6 each enclosing an angle of greater than 90° with the base 4 on the side of the hinge 10 facing the bristle bundles 8.The further the bristle bundles 8 are provided outwards (in relation to a distance from the base), the greater the distance between the opposing legs 6. As a result, the concave cleaning-active surface 14, which is indicated by a dashed line in Figure 1 in FIG. 1, is formed on both sides of a substantially U-shaped receiving space for receiving a tooth and is designated by reference numeral 16. Figures 2 and 3 illustrate the method for producing the toothbrush shown in Figure 1. Figure 2 schematically illustrates part of a bristle and bundle carrier molding device with a first tool half 18, which forms a mold cavity for injection molding the bundle carrier 2, and a second tool half 20 with holes through which the bristle bundles 8 are inserted.The bundle carrier 2 is injection-molded between these two tool halves 18, 20. In the second tool half 20, sprues communicating with the mold cavity can be provided, which are connected to a plasticizing unit via a distributor. The fastening-side ends of the bristle bundles 8 are provided with a thickened portion and protrude into the mold cavity, which is not visible in Fig. 2, since the plastic material forming the bristle carrier 2 is already poured into the first tool half 18 and encloses the fastening-side ends of the bristle bundles 8. After the plastic material has solidified, the fastening-side ends of the bristle bundles 8 are sealed in the bundle carrier 2, and the bristle-covered bundle carrier 2 can be demolded. Figure 3 schematically illustrates a part of the forming device with a support table 22 and two pivot arms 24 provided laterally on the support table 22, which can be pivoted about a pivot axis 26.The bristle-covered bundle carrier 2 is first laid flat on the support table 22, with the side arms 24 initially lying in the same plane as the support table 22 and the legs 6 of the bundle carrier 2 each resting on a pivot arm 24. The base 4 of the bundle carrier 2 is held on the support table 22 by a punch 28, while the pivot arms 24 are pivoted about their pivot axis 26, whereby the legs 6 are pivoted towards one another in their hinges 10. Figure 3 shows the situation after this pivoting process. The bristle-covered bundle carrier 2, which has also been plastically deformed in this way, can be gripped at the outer ends of the legs 6 with a gripper (not shown) and transferred to another injection mold (not shown) in order to inject the plastic material onto the hinges 10 to form the hinge reinforcement 12.Figure 4 shows a perspective side view of a variant of a bristle bundle carrier, which can be manufactured essentially in the same way as previously described in connection with Figures 2 and 3. The variant has two legs 6 at opposite ends of the base 4, wherein the bristle bundles 8 provided on the base 4 are arranged in a ring shape and the bristle bundles 8 provided on the legs 6 are arranged in two rows R1, R2. The two rows R1, R2 extend in the longitudinal direction L of the legs 8. The bristle bundles 8 of one row R1 are arranged offset from the bristle bundles 8 of the other row R2. The variant can be formed as previously described and provided with a hinge reinforcement on the hinges 10.

[0002] List of reference symbols 1 Toothbrush 2 Bundle carrier 4 Base 6 Leg 8 Bristle bundle 10 Hinge 12 Hinge reinforcement 14 Cleaning-active surface 16 Receiving space 18 First tool half 20 Second tool half 22 Support table 24 Swivel arm 26 Swivel axis 28 Punch L Longitudinal direction of the legs R1, R2 row

Claims

Claims 1. A method for producing a toothbrush (1) with a shape suitable for the simultaneous cleaning of several tooth surfaces, comprising the following steps: producing a bundle carrier (2) with a base (4) and at least two legs (6), each connected to the base (4) via a hinge (10) and each provided with at least one bundle of bristles (8), and reshaping the bundle carrier (2) into the shape suitable for the simultaneous cleaning of several tooth surfaces by pivoting the legs (6) in their hinge (10) towards each other.

2. The method according to claim 1, characterized in that the bundle carrier (2) is produced in one piece by injection molding, and at least one of the hinges (10) is designed as a film hinge.

3. The method according to claim 2, characterized in that the legs (6) and the base (4) are injection molded such that they extend in the same plane.Method according to one of claims 1 to 3, characterized in that after the legs (6) have been pivoted, a plastic material is injection-molded onto at least one of the hinges (10).

5. Toothbrush (1) with a shape suitable for the simultaneous cleaning of several tooth surfaces, characterized by a one-piece injection-molded bundle carrier (2) with a base (4) and at least two legs (6), which are each connected to the base (4) via a hinge (10) and each provided with at least one bundle of bristles (8).

6. Toothbrush (1) according to claim 5, characterized by hinge reinforcements (12) provided on the hinges (10).

7. Toothbrush (1) according to claim 5 or 6, characterized in that the bundle carrier (2) is substantially U-shaped.

8. Toothbrush (1) according to one of claims 5 to 7, characterized in that the hinge reinforcements (12) are flush with outer edges of the base (4) and outer edges of the respective leg (6).

9. Toothbrush (1) according to one of claims 5 to 8, characterized in that an outer side, which lies opposite the surfaces of the legs (6) through which the bristle bundles (8) extend, is designed to be haptic.

10. Toothbrush (1) according to one of claims 5 to 9, characterized in that two opposite sides of the base (4) are each connected to two legs (6).

11. Toothbrush (1) according to one of claims 5 to 10, characterized in that the base (4) of the bundle carrier (2) is provided with bristle bundles (8), which are preferably arranged in a ring shape.Toothbrush (1) according to one of claims 5 to 11, characterized in that at least some and preferably all of the bristle bundles (8) of each leg (6) are arranged in at least two adjacent rows (R1, R2) and offset from one another.

13. Toothbrush rail with several toothbrushes according to one of claims 5 to 12, which are arranged next to one another in a row, so that the toothbrushes lined up next to one another form a receiving space for at least a section of a dental arch comprising several teeth.

14. Device for producing a toothbrush with a shape suitable for the simultaneous cleaning of several tooth surfaces, comprising a bristle and bundle carrier forming device for producing a bundle carrier (2) with a base (4) and at least two legs (6), each of which is connected to the base (4) via a hinge (10) and each of which is provided with at least one bristle bundle (8), and. a forming device for forming the bundle carrier (2) into a shape suitable for the simultaneous cleaning of several tooth surfaces, in which the legs (6) are pivoted toward one another in their hinges (10).

15. Device according to claim 14, characterized by an injection-molding device for overmolding the formed bundle carrier (2).

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