Method for producing a toothbrush head

Patent metadata

Field	Value
Publication number	US-12433396-B2
Application number	US-202318215256-A
Country	US
Kind code	B2
Filing date	Jun 28, 2023
Priority date	Jun 21, 2019
Publication date	Oct 7, 2025
Grant date	Oct 7, 2025

Abstract

A method of making a cleaning element carrier for a toothbrush comprises: providing at least two pluralities of loose filaments of a predefined length and different from one another in at least one of filament material, filament diameter, filament cross-section, filament shape, presence or absence of additives, presence or absence of a coating, and any combination thereof; providing a hole-perforation plate having a front surface, a back surface, a thickness therebetween, and a plurality of holes shaped and arranged according to a predetermined pattern; picking filaments from the pluralities of loose filaments; providing an energy source; arranging a plurality of bristle tufts in a fusing position in the hole-perforation plate so that ends of the bristle tufts are disposed at different distances from the energy source, wherein the distances are adjustable according to the at least one property, wherein the plurality of bristle tufts includes bristle tufts comprising an inner portion bristle tufts comprising a peripheral portion, and wherein a distance between the energy source and the ends of the bristle tufts comprising the inner portion is shorter than a distance between the energy source and the ends of the bristle tufts comprising the peripheral portion; applying energy from the energy source to the ends of the tufts until fuse balls are formed at the ends of the tufts; transferring the tufts to a molding position in the hole-perforation plate so that a distance between a bottom edge of at least one fuse ball of at least one bristle tuft and the front surface of the hole-perforation plate is different from a distance between the bottom edge of the fuse ball of said tuft and the front surface of the hole-perforation plate in the fusing position; over-molding the fuse balls with molten plastic material thereby forming a cleaning element carrier.

First claim

What we claim is:

1. A method of making a cleaning element carrier for a toothbrush, the method comprising the steps of:
providing at least two pluralities of loose filaments of a predefined length, wherein the two pluralities differ from one another in at least one property selected from the group consisting of filament material, filament diameter, filament cross-section, filament shape, presence or absence of additives, presence or absence of a coating, and any combination thereof;
providing a hole-perforation plate comprising a front surface, a back surface opposite to the front surface, a thickness therebetween, and a plurality of holes shaped and arranged according to a predetermined pattern;
picking filaments from the at least two pluralities of loose filaments to arrange a plurality of bristle tufts in the hole perforation plate;
providing an energy source;
arranging the plurality of bristle tufts in a fusing position in the hole-perforation plate so that ends of the bristle tufts are disposed at different distances from the energy source, wherein the distances are adjustable according to the at least one property, wherein in a fusing position, the plurality of bristle tufts includes bristle tufts comprising an inner portion of the plurality of bristle tufts and bristle tufts comprising a peripheral portion of the plurality of bristle tufts, and wherein a distance between the energy source and the ends of the bristle tufts comprising the inner portion is shorter than a distance between the energy source and the ends of the bristle tufts comprising the peripheral portion,
applying energy from the energy source to the ends of the tufts until fuse balls are formed at the ends of the tufts;
transferring the plurality of bristle tufts to a molding position in the hole-perforation plate so that a distance between a bottom edge of at least one fuse ball of at least one bristle tuft and the front surface of the hole-perforation plate is different from a distance between the bottom edge of the fuse ball of said tuft and the front surface of the hole-perforation plate in the fusing position;
over-molding the fuse balls with molten plastic material thereby forming a cleaning element carrier.

2. The method of claim 1 , wherein the step of over-molding comprises providing the cleaning element carrier being formed with an edge having a thickness of from 0.6 mm to 1.2 mm.

3. The method of claim 1 , wherein the step of applying energy comprises applying energy until the fuse ball being formed has a shape selected from the group consisting of a plane, a plane with a central depression, a plane with a concave surface, a plane with a convex surface, and any a combination thereof.

4. The method of claim 1 , wherein the step of providing at least two pluralities of loose filaments comprises
providing a filament strand having an end,
end-rounding and polishing the end of the filament strand, and
cutting a predefined length from the filament strand.

5. The method of claim 4 , wherein the predefined length is from about 5 mm to about 20 mm.

6. The method of claim 1 , wherein in the step of arranging a plurality of bristle tufts in a fusing position, at least some of the tufts are round and have a cross-sectional area of from of 0.6 mm 2 to 3 mm 2 .

7. The method of claim 1 , wherein in the step of arranging a plurality of bristle tufts in a fusing position, the tufts form a block bristle tuft comprising filaments of more than one bristle tuft, and wherein a block bristle tuft has an area of from about 8 mm 2 to about 24 mm 2 .

8. The method of claim 1 , wherein in the step of applying energy, a distance from the energy source to the front surface of the hole perforation plate is from 0.5 mm to 7 mm.

9. The method of claim 1 , wherein in the step of arranging a plurality of bristle tufts, a distance between adjacent bristle tufts in the hole perforation plate is from 0.2 mm to 2.0 mm.

10. The method of claim 1 , wherein in the step of transferring the tufts to a molding position, the distance between the bottom edge of the fuse ball and the front surface of the hole perforation plate of at least one bristle tuft in the fusing position is greater than the distance between the bottom edge of the fuse ball and the front surface of the hole perforation plate of said at least one bristle tuft in the molding position.

11. The method of claim 1 , wherein in the step of transferring the tufts to a molding position, the distance between the bottom edge of the fuse ball and the front surface of the hole perforation plate of the bristle tufts in the molding position is from 0.2 mm to 3 mm.

12. The method of claim 11 , wherein the distance between the bottom edge of the fuse ball and the front surface of the hole perforation plate of the bristle tufts in the molding position is from 0.3 mm to 2.5 mm.

13. The method of claim 12 , wherein the distance between the bottom edge of the fuse ball and the front surface of the hole perforation plate of the bristle tufts in the molding position is from 0.4 mm to 2 mm.

14. The method of claim 13 , wherein the distance between the bottom edge of the fuse ball and the front surface of the hole perforation plate of the bristle tufts in the molding position is from 0.5 mm to 1.5 mm.

15. The method of claim 14 , wherein the distance between the bottom edge of the fuse ball and the front surface of the hole perforation plate of the bristle tufts in the molding position is from 0.6 mm to 1.2 mm.

16. The method of claim 1 , wherein the step of applying energy comprises applying thermal energy for a period of from 1 second to 15 seconds.

17. The method of claim 16 , wherein the thermal energy is applied for a period of from 2 seconds to 12 seconds.

18. The method of claim 17 , wherein the thermal energy is applied for a period of from 3 seconds to 10 seconds.

19. The method of claim 18 , wherein the thermal energy is applied for a period of from 4 seconds to 8 seconds.

Assignees

• Procter & Gamble

Inventors

• Ganninger Jochen
• Schulz Holger
• Baum Daniela

Classifications

• A46B3/06

  by welding together bristles made of metal wires or plastic materials · CPC title

• A46D3/082 Primary

  Magazines for bristles; Feeding bristles to magazines; Knot picking · CPC title

• A46D1/08

  Preparing uniform tufts of bristles · CPC title

• A46B2200/1066

  Toothbrush for cleaning the teeth or dentures (A61C17/16 takes precedence; bristles arrangements for toothbrushes A46B9/04) · CPC title

• A46B9/04

  {Arranged like in or} for toothbrushes · CPC title