Toothbrush and process for producing such a toothbrush

Abstract

The invention relates to a toothbrush having a handle and a head part, on which bristle filaments and at least one flexible cleaning element are arranged. According to the invention, the at least one flexible cleaning element is arranged on a carrier element which consists of a hard material and is connected to the head part. The invention also relates to a process for producing such a toothbrush.

Description

22 22′ made of flexible material covers the underside of the head and handle parts 1, 2.

FIGS. 9a-f show a further example of a toothbrush according to the invention. The head part 1 has a prepared region 13 for the carrier element 5 of the additional part 4, said region being larger than the carrier element 5 itself. The region 13 is, for example, a hole which passes all the way through the head part 1, see sectional drawings from FIGS. 9b, d and e. The region 13 has two lateral grooves 13a, the shape of which is adapted to the shape of two lateral extensions 5b of the carrier element 5. The latter is inserted into the head part 1 and latches there. The play of the carrier element 5 within the region 13, which allows lateral displacement and/or a pivoting movement about the axis defined by the extensions 5b, results in a particular level of elasticity or resilient action of the additional part 4. The rear side of the head part 1, again, may be covered by a layer of soft material.

FIGS. 10a-j show a further example of a toothbrush produced by means of AFT. FIGS. 10a-c correspond to FIGS. 7a-c and each show the carrier plate 5 in various process stages. FIGS. 10d-f show the same carrier plate 5 in section along line I-I indicated in FIG. 10a. The centrally arranged flexible element 6 is sheet-like or sail-like and is undulating in plan view (FIG. 10h). As is illustrated in FIGS. 10e and f, the flexible structure comprises laterally integrally formed regions 6″ which, in the assembled state (FIG. 10h), bound the toothbrush head 1 laterally and terminate more or less flush with the outer contour of the head part. They serve, for example, as impact protection and/or for additionally massaging the gums. The regions 6″ likewise have holes 21′ for accommodating clusters of bristles 3, which are thus suspended in an elastic manner and are particularly compliant during cleaning.

The carrier element 5 provided with conventional bristles 3 and the flexible structure 6, 6′, 6″ is inserted into a cutout 13 in the brush head 1. The brush head 1 is illustrated in various views without the carrier element 5 in FIGS. 10g and j and with the carrier element 5 inserted in FIGS. 10h and i. On its lateral border, the brush head 1 or the cutout 13 has lateral openings 25, which are adapted to the lateral flexible regions 6″ previously molded on the carrier element 5.

The carrier element 5 is connected to the brush head 1 by means of ultrasonic welding. The welding surface 26 is indicated by dashed lines. In order to realize the welding, the carrier element has, on its bottom border, a welding border 26′ which, during assembly, rests on the base of the cutout 13, the contact surface defining the welding surface 26. The welding border 26′ melts under the influence of ultrasound, with the result that the two parts 5 and 1 are connected to one another.

Since elastomeric material can only be welded ultrasonically to a limited extent, the welding surface 26, as far as possible, is kept free of this material, for example as in the case of the toothbrush from FIG. 7 or, with only minimal interruptions, as in the case of the toothbrush from FIG. 10. The aim, in both cases, is to seal the cavity 28 between the carrier element 5 and head part 1 to the full extent, in order to prevent the ingress of water and germs. For this purpose, the injection point of the flexible material is preferably selected to be on the bristle-carrying front side of the carrier element 5, in order that no unnecessary material bridges reduce the size of the welding surface 26. If further flexible elements 22″ are provided on the head part 1, in particular on the rear side thereof, they are positioned such that they do not reduce the size of the welding surface 26. For example, these elements and the corresponding injection point are located fully within that region on the rear side of the head part 1 (not illustrated) which is defined by the welding surface 26. The entire contact surface between the head part 1 and carrier element 5 is preferably welded over at least 25%, particularly preferably along the periphery of the head (line 26).

In the example from FIG. 10, the flexible regions 6′ interrupt the welding surface 26, with the result that non-welded locations 27 are produced there. These are advantageously arranged on the side of the head part 1, while the longitudinally front and rear regions of the carrier element 5 are firmly welded to the head part 1. This ensures that the carrier element 5 is held securely since the front and rear regions are subjected to an extremely high level of loading by the cleaning movement and corresponding leverages.

The non-welded locations 27 are sealed by the flexible regions 6″ here in the manner of a sealing lip, with the result that only a very small amount of water, if any at all, can penetrate into the cavity 28. For a good sealing function, material with a Shore A hardness of 50 or less is preferably selected. Non-welded locations between the head part and carrier element may also be used specifically, in order to achieve a certain level of flexibility between the two hard components.

FIG. 11 shows various views of a further example of a toothbrush produced by AFT, in this case, with two sail-like flexible cleaning elements 6. The carrier element 5 is fully enclosed, around its periphery, by flexible material 6′, which, in the assembled state (plan-view illustration FIG. 11a) fully encloses the outer periphery of the head part 1 on the top side and serves as impact protection. In regions 6″, the soft material serves as a mount for lateral clusters of bristles 3 which are guided through the flexible material 6′.

As can be gathered from FIG. 11c, the hard components (carrier element 5 and head part 1) come into contact with one another along a surface 26 beneath the soft component in the region 6′ and can be welded here by means of ultrasound. The welding surface 26 is interrupted by the lateral regions 6″, although, as has been described above, a sufficient retaining action is achieved. The cavity 28 beneath the carrier element 5 is sealed by the flexible regions 6″ and the locations welded along the surface 26.

The method of welding and sealing the components which has been described above with reference to FIGS. 10 and 11 may also advantageously be used for other toothbrushes.

Claims

1. A toothbrush head, comprising:

a bristle-carrying head part;

bristle filaments and a cutout provided through the head part, the cutout including a bottom opening that is of a larger cross-section than an intermediate section of the cutout; and

a flexible, non-bristle cleaning element arranged on a carrier element, the cleaning element being made of a first material and the carrier element being made of a second, harder material, the carrier element including a base and a resiliently configured extension, the base having a cross-section larger than the intermediate section of the cutout, and the extension having an intermediate portion and a bottom with a cross-section that is larger than the intermediate portion of the extension and the intermediate section of the cutout, the bottom of the extension being resiliently inserted through the intermediate section of the cutout and into the bottom opening to prevent ready release of the carrier element from the head part by a snap-fit connection.

2. The toothbrush head according to claim 1, wherein the connection is sufficient to prevent detaching of the carrier element from the head part during use of the toothbrush.

3. The toothbrush head according to claim 1, wherein the connection is non-releasable.

4. The toothbrush head according to claim 1, wherein play between the carrier element and the head part at the cutout allows movement of the carrier element and the flexible cleaning element during use of the toothbrush.

5. The toothbrush head according to claim 1, wherein the flexible cleaning element is arranged to massage gums of the user.

6. The toothbrush head according to claim 1, wherein the flexible cleaning element is made from a thermoplastic elastomer.

7. The toothbrush head according to claim 1, wherein the flexible cleaning element includes rubber.

8. The toothbrush head according to claim 1, wherein the flexible cleaning element has a Shore A hardness of less than 90.

9. The toothbrush head according to claim 1, wherein the material of the carrier element is a polypropylene, styrene-acrylonitrile, acrylonitrile-butadiene-styrene, polyurethane or polyester.

10. The toothbrush head according to claim 1, wherein the flexible cleaning element and the carrier element are produced by two-component or multi-component injection molding and mated with a non-releasable connection.

11. The toothbrush head according to claim 1, wherein the flexible cleaning element is inclined out of the vertical to come into contact with at least one of the bristle filaments.

12. The toothbrush head according to claim 1, wherein the flexible cleaning element crosses over at least one of the bristle filaments.

13. The toothbrush head according to claim 1, wherein the flexible cleaning element has a rod-like shape.

14. The toothbrush head according to claim 1, wherein the carrier element is harder than the flexible cleaning element.

15. The toothbrush head according to claim 1, wherein the cutout extends entirely through the head part.

16. The toothbrush head according to claim 1, wherein the head part includes a plurality of cutouts and a plurality of flexible cleaning elements and carrier elements.

17. The toothbrush head according to claim 1, further comprising a handle connected to the head part.

18. A toothbrush head, comprising:

a bristle-carrying head part;

bristle filaments and a cutout provided on the head part;

a flexible, non-bristle cleaning element arranged on a carrier element, the carrier element being of a harder material than that of the flexible cleaning element, the carrier element including an extension that extends into the cutout and is connected to the head part by a not readily releasable snap-fit connection of the carrier element within the cutout; and

play between the carrier element and the head part at the cutout allows pivoting movement of the carrier element about an axis.

19. The toothbrush head according to claim 18, wherein the axis is substantially perpendicular to the longitudinal axis of the head part.

20. The toothbrush head according to claim 18, wherein the connection is sufficient to prevent detaching of the carrier element from the head part during use of the toothbrush.

21. The toothbrush head according to claim 18, wherein the flexible cleaning element is made from a thermoplastic elastomer.

22. The toothbrush head according to claim 18, wherein the flexible cleaning element includes rubber.

23. The toothbrush head according to claim 18, wherein the flexible cleaning element has a Shore A hardness of less than 90.

24. The toothbrush head according to claim 18, wherein the harder material of the carrier element is a polypropylene, styrene-acrylonitrile, acrylonitrile-butadiene-styrene, polyurethane or polyester.

25. The toothbrush head according to claim 18, wherein the flexible cleaning element is inclined out of the vertical to come into contact with at least one of the bristle filaments.

26. The toothbrush head according to claim 18, wherein the flexible cleaning element has a rod-like shape.

27. The toothbrush head according to claim 18,wherein the cutout is provided through the head part and includes an end opening that is of a larger cross-section than an intermediate section of the cutout.

28. The toothbrush head according to claim 18, further comprising a handle connected to the head part.

29. The toothbrush head according to claim 18, wherein the head is also formed from a material that is harder than the flexible, non-bristle containing cleaning element so that a hard material to hard material snap-fit connection is formed.

30. The toothbrush head according to claim 18, wherein the carrier extension is a snap-fitting element, and the snap-fitting element and the carrier form a single-piece body of the harder material.

31. The toothbrush head according to claim 18, wherein the not-readily releaseable snap-fit connection is formed by one of the extension and the head part resiliently deforming.

32. The toothbrush head according to claim 18, wherein the cleaning element is non-releasably attached to the carrier element through two component or multi-component injection molding.

33. The toothbrush head according to claim 18, wherein the head involves a plurality of cutouts and a plurality of snap-fit carrier elements.

34. A process for producing a toothbrush head comprising:

providing a head part with a cutout and with bristle filaments, the cutout having a bottom end opening that is of a larger cross-section than an intermediate section of the cutout;

providing a flexible, non-bristle cleaning element coupled to a carrier element, the cleaning element being made of first material and the carrier being made of a second, harder material;

providing the carrier element with a base having a cross-section larger than the intermediate section of the cutout and an extension having an intermediate portion and a resiliently configured bottom with a cross-section that is larger than the intermediate section of the extension and the intermediate section of the cutout;

inserting the bottom of the extension through the intermediate section of the cutout and into the bottom end opening; and

connecting the carrier element to the cutout of the head part in a not-readily releasable snap-fit connection.

35. The process as claimed in claim 34, wherein the connecting occurs after the toothbrush head is provided with the bristle filaments.

36. The process as claimed in claim 34, wherein the bristle filaments provided on the head part are processed prior to connecting the carrier element to the cutout of the head part.

37. The process as claimed in claim 34, wherein the processing includes at least one of rounding, cutting and machining processing operations.

38. The process as claimed in claim 34, wherein the flexible cleaning element and the carrier element are produced by two-component or multi-component injection molding.

39. The process as claimed in claim 34, further comprising:

providing the toothbrush head part with a handle.

40. The process according to claim 34, further comprising inserting the carrier element into the cutout from a bristle bearing front face of the head part.

41. A process for producing a toothbrush head of a toothbrush comprising:

providing a head part with a cutout and bristle filaments;

providing a non-bristle cleaning element of a first material coupled to a carrier element of a second, harder material, the carrier element being formed with an extension;

inserting the extension into the cutout;

connecting the carrier element to the cutout of the head part by a not readily releasable snap-fit connection of the carrier element within the cutout; and

providing play between the carrier element and the head part at the cutout that allows pivoting movement of the carrier element about axis.

42. The process as claimed in claim 41, wherein the connecting occurs after the toothbrush head is provided with the bristle filaments.

43. The process as claimed in claim 42, wherein the bristle filaments provided on the head part are processed prior to connecting the carrier element to the head part.

44. The process as claimed in claim 43, wherein the processing includes at least one of rounding, cutting and machining processing operations.

45. The process as claimed in claim 41, wherein the flexible cleaning element and the carrier element are produced by a two-component or multi-component injection molding.

46. The process as claimed in claim 45, wherein the flexible cleaning element is produced from a thermoplastic elastomer or rubber and the carrier element is produced from a polypropylene, styrene-acrylonitrile, acrylonitrile-butadiene-styrene, polyurethane or polyester.

47. The process as claimed in claim 45, wherein the material of the flexible, non-bristle containing cleaning element and the harder material of the carrier are chosen to be compatible with each other to produce a non-releasable connection in the two component or multi-component injection molding process.

48. The process according to claim 41, further comprising:

providing the toothbrush head part with a handle.

49. The process according to claim 41, further comprising inserting the carrier element into the cutout from a bristle bearing front face of the head part.

50. A toothbrush, comprising;

a handle;

a head part;

a flexible structure made from a soft material;

a plate-like carrier element having a front side, a rear side and bristle receiving cutouts;

the carrier element being of a harder material than that of the flexible structure and connected to the head part such that the rear side of the carrier element faces a front side of the head part; and

bristle filaments guided through the bristle receiving cutouts, rear ends of the bristle filaments being melted, welded or adhesively bonded on the rear side of the carrier element;

wherein the flexible structure is provided on the head part and a corresponding injection point of the flexible structure is located on a rear side of the head part.

51. The toothbrush as claimed in claim 50, wherein a contact surface defining a welding surface between the carrier element and the head part is kept free from the soft material of the flexible structure.

52. The toothbrush as claimed in claim 51, wherein at least one flexible region interrupts the welding surface, with the result that non-welded locations are present.

53. The toothbrush as claimed in claim 52, wherein the head part comprises at least one lateral opening having a shape adapted to the at least one flexible region arranged laterally on the carrier element.

54. The toothbrush as claimed in claim 50, wherein at least one further flexible structure is attached to the plate-like carrier element.

55. The toothbrush as claimed in claim 54, wherein bristle receiving cutouts are provided in the further flexible structure.

56. The toothbrush as claimed in claim 50, wherein a play between the carrier element and the head part allows movement of the carrier element during use of the toothbrush.

57. The toothbrush as claimed in claim 50, wherein a non-releasable connection is provided between the carrier element and the head part.

58. The toothbrush as claimed in claim 57, wherein the non-releasable connection is achieved by clamping, snap-fitting, riveting, adhesive bonding, welding, ultrasonic welding or the supply of heat.

59. The toothbrush as claimed in claim 50, wherein the carrier element consists of the same material as the head part.

60. The toothbrush as claimed in claim 50, wherein the material of the carrier element is polypropylene, styrene-acrylonitrile, acrylonitrile-butadienestyrene, polyurethane or polyester.

61. The toothbrush as claimed in claim 50, wherein an injection point of a flexible material is located on the carrier element within a region defined by a connecting border between the carrier element and the head part.

62. The toothbrush as claimed in claim 61, wherein contacting locations between the head part and the carrier element are covered with the flexible material.

63. The toothbrush as claimed in claim 61, wherein the flexible material includes natural or synthetic rubber.

64. The toothbrush as claimed in claim 61, wherein the flexible material includes a thermoplastic elastomer.

65. The toothbrush as claimed in claim 61, wherein the flexible material has a Shore A hardness of less than 90.

66. A process for producing a toothbrush with a handle, a head part and a flexible structure made from a soft material, comprising:

providing a plate-like carrier element having a front side and a rear side and made from a harder material than that of the flexible structure;

providing a plurality of bristle filaments and guiding them through bristle receiving cutouts in the carrier element;

fastening rear ends of the bristles filaments on the rear side of the carrier element by melting, welding or adhesive bonding;

connecting the carrier element to the head part in a non-releasable manner such that the rear side of the carrier element faces a front side of the head part; and

injecting the soft material to an injection point on a rear side of the head part to provide the flexible structure on the head part.

67. A process for producing a toothbrush with a handle, a head part and a flexible structure made from a soft material, comprising:

providing a carrier element with at least one cleaning element and having a front side and a rear side and made from a harder material than that of the flexible structure;

connecting the carrier element to the head part in a non-releasable manner such that the rear side of the carrier element faces a front side of the head part; and

injecting the soft material to an injection point on a rear side of the head part to provide the flexible structure on the head part.