ABRASIVE BRISTLE, METHOD FOR THE MANUFACTURE THEREOF, BRUSH WITH ABRASIVE BRISTLES AND METHOD FOR THE SURFACE TREATMENT OF A WORKPIECE WITH A BRUSH HAVING ABRASIVE BRISTLES

Abstract

For the manufacture of an abrasive bristle, a plastic material is melted, and a granular material made of abrasive particles is mixed into the melt. The melt is extruded together with the abrasive particles into a filament, and the filament is subsequently treated and cut up. The plastic material may be a high-temperature-resistant polymer with a continued use temperature of ≧150° C. and for the melt with the abrasive particles to be extruded at a temperature of ≧280° C. A brush equipped with corresponding abrasive bristles can be used for the surface treatment of a workpiece, whereby the brush is rotated with a speed in the range of 3,000 rpm to 12,000 rpm and is brought into contact with the surface to be treated.

Description

FIELD OF THE INVENTION

The invention pertains to a method for the manufacture of an abrasive bristle, wherein a plastic material is melted and a granular material made of abrasive particles is mixed into the melt, and wherein the melt with the abrasive particles is extruded into a filament, and the filament is subsequently treated and cut up. Further, the present invention pertains to a corresponding abrasive bristle.

Furthermore, the present invention pertains to a brush with abrasive bristles and a method for the surface treatment of a workpiece with a brush, which has abrasive bristles or consists of same.

BACKGROUND OF THE INVENTION

Abrasive bristles of the type mentioned are usually used wherever a surface of a workpiece must be treated and in particular be abraded or polished.

The abrasive bristles are usually manufactured by a plastic material, for example, made of polyamide 6.12 being melted in an extruder. Granular material-type abrasive particles are mixed into the plastic melt and the melt is extruded together with the abrasive particles through a nozzle and fed in the form of a so-called endless filament to further treatment stations, in which the filament can be stretched and/or heated and/or shrunk. The filament is then cut to a desired length for the manufacture of the individual bristles.

It has been shown that such abrasive bristles can perform their abrasive treatment function only for a relatively short use time. When the bristles are drawn over the workpiece to be treated, for example, in the form of a rotating brush, high forces arise, which reduce the usability of the individual bristle.

SUMMARY OF THE INVENTION

The basic object of the present invention is to create an abrasive bristle, which has a long duration of use, and a method for the manufacture of a corresponding abrasive bristle. Furthermore, a brush with abrasive bristles and a method for the surface treatment of a workpiece shall be created, with which the workpiece can be treated quickly and in a cost-effective manner.

This object is accomplished according to the present invention by a method with a plastic material that is melted and a granular material made of abrasive particles that is mixed into the melt. The melt with the abrasive particles is extruded into a filament, and the filament is subsequently treated and cut up. Here, provisions are made for the plastic material to be a high-temperature-resistant polymer with a continued use temperature of ≧150° C. and for the melt with the abrasive particles to be extruded at a temperature of ≧280° C.

The continued use temperature represents the temperature limit, above which a substantial reduction of the strength properties of the plastic material occurs due to technical stress. The continued use temperature (also called Relative Temperature Index, RTI) is the highest temperature, at which the material still has at least 50% of its properties (tensile strength or resistance to stretching) after a set time interval of usually 20,000 hr. (see also International Standard IEC 60216-1).

The present invention is based on the basic idea that the problems with the previous abrasive bristles were caused by a relatively great friction developing between the abrasive bristles and the workpiece when using the abrasive bristles, which leads to high temperatures, which reduces the stability of the abrasive bristles. This is avoided, according to the present invention, by the plastic material, i.e., the matrix of the abrasive bristle, consisting of a high-temperature-resistant polymer. The bristles may consist of polyketones (e.g., polyether ether ketones (PEEK), polyaryl ether ketones (PAEK) or mixtures thereof), polyphenylene sulfide (PPS) or of alloys of polyarylene sulfide, or polyphenylene sulfide and polyaryl ether ketone, partially aromatic polyamides such as polyphthalamides (PPA) (e.g., PA 3T, PA 6T or PA 9T, etc., among others), or even of mixtures or blends of these plastics.

The filaments according to the present invention may be round or n-angular with n ≧3 as well as in the form of a small strip.

In order to achieve a good embedding of the abrasive particles into the plastic material, the melt with the abrasive particles is extruded at a temperature of ≧280° C. In a preferred embodiment of the present invention, provisions are made for the melt with the abrasive particles to be extruded at a temperature of 300° C. to 400° C.

In a variant of the present invention, provisions are made for the plastic material to be partially crystalline. This makes it possible to subsequently stretch the filament manufactured with the extrusion, such that the filament does not tear or is otherwise damaged.

Particles made of SiC and/or of Al₂O₃, for example, can be used as abrasive particles. However, it is also possible to provide diamond chips or particles and/or corundum particles and/or ceramic particles and/or boron carbide particles as abrasive particles.

In order to improve the adhesion between the plastic material and the abrasive particles, these can be coated with an adhesive before mixing into the plastic melt. In this connection, a coating with silanes, for example, is known from the literature.

The abrasive particles can be inserted into the melted plastic material and brought together with same to the extrusion temperature of ≧280° C. As an alternative, however, it is also possible at first to bring the plastic material to a temperature of ≧280° C. and thereby melt the plastic material and only then mix the abrasive particles into the melt.

With regard to the abrasive bristle, the above-mentioned object is accomplished by an abrasive bristle with abrasive particles that consist of SiC and/or Al₂O₃ and/or are formed by diamond particles and/or corundum particles and/or ceramic particles and/or boron carbide particles and/or zirconium oxide. Provisions are made for the plastic material to be a high-temperature-resistant plastic material.

Further features of the abrasive bristle according to the present invention as well as the advantages given therewith are already mentioned in connection with the method according to the present invention, to which reference is made for the purpose of avoiding repetitions.

The abrasive bristles according to the present invention are used for the surface treatment of a workpiece, in particular in a brush, which has a bristle carrier, which carries a bristle filling, whereby the bristle filling has abrasive bristles or abrasive bristles manufactured according to a process that includes melting a plastic material and mixing a granular material made of abrasive particles into the melt, wherein the melt with the abrasive particles is extruded into a filament, and the filament is subsequently treated and cut up, wherein the plastic material is a high-temperature-resistant polymer with a continued use temperature of ≧150° C., and the melt with the abrasive particles is extruded at a temperature of ≧280° C. The melt with the abrasive particles may be extruded at a temperature of 300° C. to 400° C. The abrasive particles may be mixed into the melt at a temperature of ≧280° C. The abrasive bristles are made of a plastic material, into which abrasive particles are mixed, wherein the plastic material is a high-temperature-resistant material with a continued use temperature of ≧150° C. The plastic material may be partially crystalline. The abrasive particles may consist of SiC and/or Al₂O₃ and/or are formed by diamond particles and/or corundum particles and/or ceramic particles and/or boron carbide particles and/or zirconium oxide. The abrasive particles may be coated with an adhesive. Preferably, the bristle filling consists entirely of corresponding abrasive bristles.

With a corresponding brush, a material abrasion on the surface of the workpiece and thus its fast treatment can be achieved without there being a risk that forces developing during the treatment and especially temperatures lead to a compromise of the functionality of the abrasive bristles and thus of the brush.

According to a method according to the present invention for the surface treatment of a workpiece by means of a brush, which has abrasive bristles made of a plastic material, into which abrasive particles are mixed, with the plastic material being a high-temperature-resistant material with a continued use temperature of ≧150° C. or abrasive bristles manufactured according to the method that includes melting a plastic material and mixing a granular material made of abrasive particles into the melt, wherein the melt with the abrasive particles is extruded into a filament, and the filament is subsequently treated and cut up, and the plastic material is a high-temperature-resistant polymer with a continued use temperature of ≧150° C., and the melt with the abrasive particles is extruded at a temperature of ≧280° C. The brush is rotated and brought into contact with the surface to be treated. The brush here has a speed of 3,000 rpm to 12,000 rpm and in particular a speed of 5,000 rpm to 9,000 rpm. These very high rotation speeds of the brush lead to a very high material abrasion and to the fast treatment of the workpiece. The relatively high temperatures occurring here may be withstood by the abrasive bristles according to the present invention without compromising the mode of action.

Preferably, the size of the brush and in particular the length of the bristles are designed such that the bristle ends are moved with a peripheral speed of 5,000 m/min to 7,000 m/min.

The method is particularly effective when the bristle filling of the brush being used in the method consists entirely of abrasive bristles made of a plastic material, into which abrasive particles are mixed, and the plastic material is a high-temperature-resistant material with a continued use temperature of ≧150° C. or of abrasive bristles, which are manufactured according to the method that includes melting a plastic material and mixing a granular material made of abrasive particles the melt, wherein the melt with the abrasive particles is extruded into a filament, and the filament is subsequently treated and cut up, and the plastic material is a high-temperature-resistant polymer with a continued use temperature of ≧150° C., and the melt with the abrasive particles is extruded at a temperature of ≧280° C.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a diagrammatic view of a flow chart showing the steps of a method of the present invention;

FIG. 2 is a side view of an apparatus for forming a filament of the present invention;

FIG. 3 is a side view of a bristle carrier of the present invention; and

FIG. 4 is a perspective view of a brush of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a flow chart showing the steps of a method of the present invention. A plastic material is melted in step 1. In step 3, a granular material is mixed into the melted plastic material. In another embodiment, the plastic material can be melted and the granular material can be mixed with the plastic material at the same time. The melted plastic material with the abrasive particles is extruded into a filament in step 5. The filament is treated and cut in step 7. In another embodiment, it is possible to cut the filament in one step and then treat the filament in another step. In yet another embodiment, the filament can be treated in one step and then cut in another step.

FIG. 2 is a side view of an apparatus for forming a filament 13. A mixer 9 receives a melted plastic material and abrasive particles. The abrasive particles may be coated with an adhesive. The melted plastic material and the abrasive particles are mixed in the mixer 9. An extruder 11 receives the melted plastic material with the abrasive particles. The extruder 11 forms the filament 13. The melted plastic material with the abrasive particles are extruded at a temperature greater or equal to than 280° C., preferably at a temperature of 300° C. to 400° C. A cutting and treating structure 15 is provided to cut and treat the filament 13. In another embodiment, the extruder 11 may receive the melted plastic material separately from the abrasive particles such that the extruder 11 mixes the melted plastic material with the abrasive particles. In another embodiment, a device may be provided for cutting the filament that is separate from a device that treats the filament.

FIG. 3 is a side view of a bristle carrier 17. The bristle carrier 17 carries a bristle filling 19. The bristle filling 19 has abrasive bristles 21. The abrasive bristles 21 include a plastic material and abrasive particles with the plastic material having a high-temperature-resistant material with a continued use temperature that is greater than or equal to 150° C.

FIG. 4 is a perspective view of a brush 23. The abrasive bristles 21 are connected to the brush 23. In one embodiment, the abrasive bristles 21 are connected directly to the brush 23. In another embodiment, the abrasive bristles 21 are connected to the brush 23 via the bristle carrier 17 of FIG. 3. The brush 23 may be rotated, such as by a motor, at a speed of 3,000 rpm to 12,000 rpm, preferably in a range of 5,000 rpm to 9,000 rpm. Ends of the bristles may be moved with a peripheral speed of 5,000 m/min to 7,000 m/min.

While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

Claims

1. A method for manufacture of an abrasive bristle, the method comprising: melting a plastic material and mixing a granular material made of abrasive particles into the melt;extruding the melt with the abrasive particles into a filament; andtreating and cutting the filament, the plastic material comprising a high-temperature-resistant polymer with a continued use temperature greater than or equal to 150° C., and the melt with the abrasive particles being extruded at a temperature greater than or equal to 280° C.

2. A method in accordance with claim 1, wherein the melt with the abrasive particles is extruded at a temperature of 300° C. to 400° C.

3. A method in accordance with claim 1, wherein the plastic material is partially crystalline.

4. A method in accordance with claim 1, wherein the abrasive particles comprise SiC and/or Al2O3 and/or are formed by diamond particles and/or corundum particles and/or ceramic particles and/or boron carbide particles and/or zirconium oxide.

5. A method in accordance with claim 1, wherein the abrasive particles are coated with an adhesive.

6. A method in accordance with claim 1, wherein the abrasive particles are mixed into the melt at a temperature greater than or equal to 280° C.

7. An abrasive bristle, comprising: a plastic material, into which abrasive particles are mixed, said plastic material comprising a high-temperature-resistant material with a continued use temperature greater than or equal to 150° C.

8. An abrasive bristle in accordance with claim 7, wherein the plastic material is partially crystalline.

9. An abrasive bristle in accordance with claim 7, wherein the abrasive particles comprise SiC and/or Al2O3 and/or are formed by diamond particles and/or corundum particles and/or ceramic particles and/or boron carbide particles and/or zirconium oxide.

10. An abrasive bristle in accordance with claim 7, wherein the abrasive particles are coated with an adhesive.

11. A brush for a surface treatment of a workpiece, the brush comprising: a bristle carrier, which carries a bristle filling, whereby the bristle filling has one of bristle filling abrasive bristles and manufactured abrasive bristles, said bristle filling abrasive brittles comprising a bristle filling plastic material, into which bristle filling abrasive particles are mixed, said bristle filling plastic material comprising a high-temperature-resistant material with a continued use temperature greater than or equal to 150° C., said manufactured abrasive bristles being manufactured according to a method, said method comprising melting a manufactured abrasive bristles plastic material and mixing a granular material made of manufactured abrasive bristles abrasive particles into the melt, extruding the melt with the manufactured abrasive bristles abrasive particles into a filament at a temperature greater than or equal to 280° C., and treating and cutting the filament, the manufactured abrasive bristles plastic material comprising a high-temperature-resistant polymer with a continued use temperature greater than or equal to 150° C.

12. A brush in accordance with claim 11, wherein the bristle filling consists entirely of said one of said bristle filling abrasive bristles and said manufactured abrasive bristles.

13. A method for a surface treatment of a workpiece, the method comprising: providing a brush, which has one of brush abrasive bristles and manufactured brush abrasive bristles, said brush abrasive bristles comprising a brush abrasive bristles plastic material and brush abrasive particles, said brush abrasive bristles plastic material comprising a brush abrasive bristles high-temperature-resistant material with a continued use temperature greater than or equal to 150° C., said manufactured brush abrasive bristles being manufactured via a manufacturing method, said manufacturing method comprising melting a manufactured plastic material and mixing a granular material made of manufactured abrasive particles into the manufactured plastic material melt, extruding the melt with the manufactured abrasive particles into a filament at a temperature greater than or equal to 280° C., and treating and cutting the filament, wherein the manufactured plastic material comprises a manufactured high-temperature-resistant polymer with a continued use temperature greater than or equal to 150° C.,rotating the brush and bringing the brush into contact with the surface to be treated, wherein the brush is rotated with a speed of 3,000 rpm to 12,000 rpm.

14. A method in accordance with claim 13, wherein the brush is rotated with a speed in a range of 5,000 rpm to 9,000 rpm.

15. A method in accordance with claim 13, wherein ends of the bristles are moved with a peripheral speed of 5,000 m/min to 7,000 m/min.

16. A method in accordance with claim 13, wherein the bristle filling of the brush consists entirely of said one of said brush abrasive bristles and said manufactured abrasive bristles.