Method for producing a toothbrush head or a part thereof

Patent metadata

Field	Value
Publication number	US-11944189-B2
Application number	US-202016898359-A
Country	US
Kind code	B2
Filing date	Jun 10, 2020
Priority date	Jun 21, 2019
Publication date	Apr 2, 2024
Grant date	Apr 2, 2024

Abstract

A method for producing a toothbrush head comprises providing at least two bristle tufts that differ in at least one property; arranging the tufts in a hole-perforation plate comprising holes shaped and distributed according to the desired bristle field; arranging an energy source so that the ends of the bristle tufts and the energy source are arranged contactless, wherein the ends of the bristle tufts to be fused are arranged at different distances to the energy source and are adjusted according to the different property; applying energy to the ends of the bristle tufts until fuse balls are formed; transferring the bristle tufts to a subsequent process position, wherein the distance of the fuse ball of at least one bristle tuft to the hole-perforation plate is different from the distance of said fuse ball to the hole-perforation plate in the fusing position before; over-molding of the fuse balls of the bristle tufts with plastic material thereby forming the brush head or the part ( 10 ) thereof.

First claim

What we claim is:

1. A method of producing a toothbrush head or a part thereof, comprising:
providing at least two bristle tufts, each comprising a plurality of bristle filaments, wherein the at least two bristle tufts differ from one another in at least one property;
arranging the at least two bristle tufts in a hole perforation plate comprising a front surface, a back surface, a thickness therebetween, and a plurality of holes therethrough, wherein the plurality of holes is shaped and distributed in the hole perforation plate according to a desired bristle field of the brush head being produced;
arranging an energy source at a predefined distance to the front surface of the hole perforation plate so that ends of the at least two bristle tufts and the energy source are arranged contactless;
arranging the at least two bristle tufts in a fusing position, wherein the ends of the at least two bristle tufts to be fused are arranged in the hole perforation plate at different distances to the front surface resulting in different distances of the bristle tuft ends to the energy source, wherein the distance is adjusted according to the at least one property of the at least two bristle tufts, wherein in the fusing position, the distance between the energy source and the bristle tuft ends of the bristle tufts decreases with increasing cross-section of the bristle tuft;
applying energy from the energy source to the ends of the at least two bristle tufts until fuse balls are formed at the ends of the at least two bristle tufts;
transferring the at least two bristle tufts to a subsequent process position, wherein a distance of the bottom edge of the fuse ball of at least one bristle tuft to the front surface is different from a distance of the bottom edge of the fuse ball of said bristle tuft to the front surface in the fusing position; and
over-molding the fuse balls of the at least two bristle tufts with plastic material, thereby forming the brush head or the part thereof.

2. The method of claim 1 , wherein the at least one property is selected from the group consisting of a size of the bristle tuft, a form of the bristle tuft, a position of the bristle tuft in the hole perforation plate and/or in the desired bristle field of the brush head to be produced, a material of the bristle filaments, a diameter of the bristle filaments, a cross-section of the bristle filaments, a shape of the bristle filaments, an additives present in the bristle filaments, and any combination thereof.

3. The method of claim 1 , wherein energy is applied until the fuse ball has a shape selected from the group consisting of a plane shape, a plane shape with a central depression, a plane shape with a concave portion, a plane shape with a convex portion, and any combination thereof.

4. The method of claim 1 , wherein a ratio of an outline of the fuse ball to an outline of the bristle tuft is selected from the group consisting of a ratio of at least 1.05:1, a ratio of at least 1.1:1, a ratio of at least 1.2:1, and a ratio of at least 1.3:1.

5. The method of claim 1 , wherein the energy source is a thermal energy source selected from the group consisting of a heater, a convection heater, a thermal-radiation heater, and any combination thereof.

6. The method of claim 5 , wherein the heater comprises a heating plate comprising at least one heating surface at least partly made of a conductive material for emitting thermal radiation when an electric current flows through the conductive material.

7. The method of claim 6 , wherein the at least one heating surface is non-flat and is selected from the group consisting of a concave surface, convex surface, and any combination thereof.

8. The method of claim 5 , wherein a flow of thermal energy flows from the thermal energy source to the at least two bristle tuft ends located in the hole perforation plate, wherein a temperature is in the range selected from the group consisting of a range of from 500° C. to 1000° C., a range of from 600° C. to 900° C., and a range of from 650° C. to 850° C.

9. The method of claim 5 , wherein the distance from the thermal energy source to the front surface of the hole perforation plate is in the range selected from the group consisting of a range of from 0.5 mm to 7 mm and a range of from 0.5 mm to 4 mm.

10. The method of claim 1 , wherein the at least two bristle tufts include a plurality of bristle tufts including peripherally located bristle tufts and centrally located bristle tufts located between the peripherally located bristle tufts, wherein in a fusing position the distance between the energy source and the bristle tuft ends of the centrally located bristle tufts is shorter than the distance between the energy source and the bristle tuft ends of the peripherally located bristle tufts.

11. The method of claim 10 , wherein the distance between the energy source and the bristle tuft end of the bristle tuft that is arranged most central in the plurality of bristle tufts is the shortest.

12. The method of claim 1 , wherein 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 larger 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 subsequent process position.

13. The method of claim 1 , 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 in a range selected from the group consisting of a range of from 0.2 mm to 3 mm, a range of from 0.3 mm to 2.5 mm, a range of from 0.4 mm to 2 mm, a range of from 0.5 mm to 1.5 mm, and a range of from 0.6 mm to 1.2 mm.

14. The method of claim 1 , wherein an application time of energy from the energy source during fusing is in a range selected from the group consisting of a range of from 1 sec to 15 sec, a range of from 2 sec to 12 sec, a range of from 3 sec to 10 sec, a range of from 4 sec to 8 sec, and a range of from 5 sec to 7 sec.

15. A method of producing a toothbrush head or a part thereof, comprising:
providing at least two bristle tufts, each comprising a plurality of bristle filaments, wherein the at least two bristle tufts differ from one another in at least one property;
arranging the at least two bristle tufts in a hole perforation plate comprising a front surface, a back surface, a thickness therebetween, and a plurality of through-holes shaped and distributed in the hole perforation plate corresponding to a desired bristle field of the brush head being produced;
arranging an energy source at a predefined distance to the front surface of the hole perforation plate so that ends of the at least two bristle tufts and the energy source are arranged contactless;
arranging the at least two bristle tufts in a fusing position, wherein the ends of the at least two bristle tufts to be fused are arranged in the hole perforation plate at different distances to the front surface resulting in different distances of the bristle tuft ends to the energy source, wherein the distance is adjusted according to the at least one property of the at least two bristle tufts, wherein in the fusing position, the distance between the energy source and the bristle tuft ends of bristle tufts comprising bristle filaments having a smaller diameter is larger than the distance between the energy source and the bristle tuft ends of bristle tufts comprising bristle filaments having a larger diameter, and wherein the distance increases with increasing bristle filamen

Assignees

• Procter & Gamble

Inventors

• Ganninger Jochen
• Baum Daniela

Classifications

• A46D3/005 Primary

  by moulding or casting a body around bristles or tufts of bristles · CPC title

• A46B3/06

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

• A46B9/04

  {Arranged like in or} for toothbrushes · CPC title

• A46D1/08

  Preparing uniform tufts of bristles · CPC title

• A46D3/045

  for fixing bristles by fusing or gluing to a body · CPC title