Method for producing brushes, in particular interdental brushes, and brush, in particular interdental brush, and product group comprising a plurality of brushes

Patent metadata

Field	Value
Publication number	US-10299577-B2
Application number	US-201314410536-A
Country	US
Kind code	B2
Filing date	May 14, 2013
Priority date	Jul 2, 2012
Publication date	May 28, 2019
Grant date	May 28, 2019

Abstract

The invention relates to a brush, in particular an interdental brush, which comprises a bristle-carrying stem defining a longitudinal direction and having an elongate support core, a bristle area having bristles projecting from the bristle-carrying stem, and a neck element connecting the support core to a handle, wherein the handle, the support core and the neck element are injection molded integrally from a first plastics component, and wherein a second plastics component in the form of an integral layer and the bristles projecting therefrom is mounted on the support core. The invention also relates to corresponding product groups and to a corresponding method.

First claim

The invention claimed is:

1. A brush comprising:
a handle having a front end; and
a bristle-carrying stem having a longitudinal axis defining a longitudinal direction and including an elongated support core, an integral layer disposed on the support core, a bristle field having bristles configured to protrude from the integral layer and a neck element configured to connect the support core to the handle,
wherein the handle, the support core and the neck element are integrally formed from a first plastics material component,
the integral layer is formed from a second plastics material component by injecting the second plastics material component at an injection portion, which is situated at the front end of the handle facing the neck element,
the second plastics material component overlaps a part of a surface of the handle and covers a part of a surface on a rear side of the neck element, and
the neck element comprises a longitudinal, channel-like indentation configured to support flow of the second plastics material component from the handle to the support core.

2. The brush as claimed in claim 1 , wherein the second plastics material component partially surrounds the neck element.

3. The brush as claimed in claim 1 , wherein the integral layer forms a casing of the support core in a region of the bristle stem.

4. The brush as claimed in claim 1 , wherein a diameter of the support core is smaller than a diameter of the neck element.

5. The brush as claimed in claim 1 , wherein the integral layer is disposed on the support core flush with the neck element.

6. The brush as claimed in claim 1 , wherein the support core has a round, triangular or trapezoidal cross-section.

7. The brush as claimed in claim 1 , wherein the handle includes a notch disposed on an end of the handle opposite to the neck element in the longitudinal direction.

8. The brush as claimed in claim 1 , wherein the support core tapers toward an end of the support core opposite to the neck element in the longitudinal direction.

9. The brush as claimed in claim 1 , wherein the bristles are configured to protrude in a non-radial direction from the longitudinal axis of the support core.

10. The brush as claimed in claim 1 , wherein a length of the bristles decreases toward an end of the bristle stem opposite to the neck element in the longitudinal direction.

11. The brush as claimed in claim 1 , wherein the bristle field includes two rows of bristles, the two rows protruding substantially horizontally from the support core in a plane below the longitudinal axis of the support core.

12. The brush as claimed in claim 1 , wherein the bristle field includes three rows of bristles, the three rows converging toward an end of the bristle stem opposite to the neck element in the longitudinal direction and being arranged on a top surface of the support core.

13. The brush as claimed in claim 1 , wherein the second plastics material component substantially covers a surface of the support core.

14. The brush as claimed in claim 1 , wherein the bristle field includes two rows of bristles, the two rows converging toward an end of the bristle stem opposite to the neck element in the longitudinal direction, being arranged on a top surface of the support core and protruding from the top surface in an outward direction.

15. The brush as claimed in claim 1 , wherein the handle has a flat shape.

16. The brush as claimed in claim 15 , wherein the handle has a top surface and a bottom surface, both surfaces including trough-shaped indentations and at least one hole configured to accommodate a fingertip.

17. The brush as claimed in claim 16 , wherein the second plastics material component is disposed in the trough-shaped indentations and the at least one hole.

18. The brush as claimed in claim 16 , wherein the trough-shaped indentations include a structure.

19. The brush as claimed in claim 18 , wherein the structure is disposed on an edge or a bottom of the trough-shaped indentations.

20. The brush as claimed in claim 18 , wherein the structure is at least one selected from the group consisting of nubs, grooves and lamellae.

21. The brush as claimed in claim 20 , wherein at least one component of the structure projects through another component of the structure inside the structure.

22. The brush as claimed in claim 16 , wherein the trough-shaped indentations include closed and open trough-shaped indentations,
in the closed indentations, edges of the trough-shaped indentations are continuous, and
in the open indentations, the trough-shaped indentations are open at least at one end.

23. The brush as claimed in claim 16 , wherein the at least one hole is circular, oval or polygonal.

24. The brush as claimed in claim 16 , wherein the surfaces include small plates, and the small plates are oval, circular or rectangular.

25. A product group comprising several brushes as claimed in claim 1 , wherein handles of adjacent brushes are connected by a material bridge formed from the first plastics material component.

26. A product group comprising several brushes as claimed in claim 1 , wherein handles of adjacent brushes are connected by a material bridge formed from the first plastics material component and a material bridge formed from the second plastics material component.

27. A method for producing a brush comprising (i) a handle having a front end, and (ii) a bristle-carrying stem having a longitudinal axis defining a longitudinal direction and including an elongated support core, an integral layer disposed on the support core, a bristle field having bristles configured to protrude from the integral layer and a neck element configured to connect the support core to the handle, the method comprising:
injecting the handle, the neck element and the support core integrally from a first plastics material component;
introducing the support core in a longitudinal direction through a bristle field cavity opening of an injection mold into a bristle field cavity;
fixing the support core introduced into the bristle field cavity to avoid movement of the support core in the longitudinal direction; and
applying a second plastics material component from an injection point of the injection mold onto the support core at an injection portion, which is situated at the front end of the handle facing the neck element to form the integral layer on the support core and the bristles protruding therefrom in an integral manner,
wherein the second plastics material component overlaps a part of a surface of the handle and covers a part of a surface on a rear side of the neck element, and
the neck element comprises a longitudinal, channel-like indentation configured to support flow of the second plastics material component from the handle to the support core.

28. The method as claimed in claim 27 , wherein the second plastics material component partially surrounds the neck element.

29. The method as claimed in claim 27 , wherein the support core, the neck element and the handle are injected in another cavity of the injection mold, the other cavity being separate from the bristle field cavity.

30. The method as claimed in claim 27 , wherein the integral layer forms a casing of the support core in a region of the bristle stem.

31. The method as claimed in claim 27 , wherein the supp

Assignees

• Trisa Holding Ag

Inventors

• Schär Michael
• Zurfluh Peter

Classifications

• B29L2031/42

  Brushes · CPC title

• B29C45/2708

  Gates (B29C45/2703 takes precedence) · CPC title

• B29C45/1671

  with an insert · CPC title

• B29C45/14065

  Positioning or centering articles in the mould · CPC title

• A46D3/00

  Preparing, {i.e. Manufacturing} brush bodies · CPC title