JP2024151103A - Abrasive brush and manufacturing method thereof - Google Patents

Abstract

[Problem] To provide an abrasive brush in which the wire is unlikely to break and has good abrasive efficiency, and a manufacturing method thereof. [Solution] The abrasive brush 100 has a cylindrical brush 10 and a cylindrical holder 20. The brush 10 is made by bundling a number of wires 2 and fixing one end of each of the bundles 4 together, and then assembling a number of bundles 4 into a cylindrical shape with their fixed ends 4a aligned on the same plane and fixed to each other. The holder 20 has a circular bottom wall 22 facing the fixed end 10a of the brush 10, and a cylindrical peripheral wall 24 that is continuous with the outer periphery 22b of the bottom wall 22 so as to project the free end 2b of the wire 2 opposite the fixed end 10a of the brush 10 and partially cover the outer periphery of the brush 10. The holder 20 accommodates and fixes the fixed end 10a side of the brush 10. [Selected Figure] Figure 2

Description

The present invention relates to an abrasive brush for removing burrs that occur, for example, during metal cutting, and a method for manufacturing the same.

Conventionally, abrasive brushes have been known that are attached to electric hand tools such as grinders or tools that use air pressure as a grinding tool used for polishing, grinding, deburring, removing rust, and stripping paint from metals.

The abrasive brush of Patent Document 1 has multiple wire assemblies, each of which is made up of multiple wires bundled together and fixed at one end, and has a structure in which the fixed ends of the multiple wire assemblies are attached to multiple holes arranged in parallel along the outer periphery of a circular brush holder.

JP 2020-55104 A

The polishing brush of Patent Document 1 has fixed ends of wire assemblies attached to multiple holes arranged side by side on the outer periphery of the brush holder, so there are gaps between adjacent wire assemblies in the circumferential direction. This results in low wire density, poor polishing efficiency, and the wires being prone to breaking.

The present invention was made in light of the above-mentioned circumstances, and its purpose is to provide an abrasive brush whose wire is less likely to break and has good abrasive efficiency, as well as a method for manufacturing the same.

The abrasive brush according to one embodiment of the present invention has a cylindrical brush and a cylindrical holder. The brush is made by bundling multiple wires and fixing one end of each wire together, aligning the fixed ends of the bundle on the same plane, and assembling multiple bundles into a cylinder and fixing the fixed ends together. The holder has a circular bottom wall portion facing the fixed end of the brush, and a cylindrical peripheral wall portion that is continuous with the outer periphery of the bottom wall portion so that the free ends of the wires opposite the fixed end of the brush protrude and partially cover the outer periphery of the brush. The holder accommodates and fixes the fixed end side of the brush.

The holder may further have a cylindrical protrusion extending from the center of the bottom wall along the inner circumferential surface of the brush.

The wire is made of resin and contains abrasive grains, the bundle is made of multiple wires fixed together at one end by welding, the brush may be made of multiple bundles fixed together at their fixed ends by welding, and the holder may be made of resin. The brush may be fixed to the inner surface of the bottom wall of the holder, the inner circumferential surface of the bottom wall side of the peripheral wall, and the outer circumferential surface of the protruding portion by adhesive.

The peripheral wall of the holder may have a number of slits arranged in the circumferential direction with a number of ribs between them, and the rib may have two side surfaces that converge from the edges of two adjacent slits on both sides in the circumferential direction toward the inner peripheral surface of the peripheral wall. By cutting the multiple ribs, the axial length of the peripheral wall can be shortened.

According to another embodiment of the present invention, a method for manufacturing an abrasive brush includes the steps of bundling a plurality of resin wires containing abrasive grains, aligning one end of each wire to the same plane, and welding and fixing the ends together to form a wire bundle; aligning the fixed ends of the bundles to the same plane, assembling them into a cylinder, and welding and fixing the fixed ends of the bundles together to form a cylindrical brush; and fixing the brush and holder by placing the fixed end of the brush in a holder having a circular bottom wall portion facing the fixed end of the brush and a cylindrical peripheral wall portion connected to the outer periphery of the bottom wall portion so that the free ends of the wires opposite the fixed end of the brush protrude and partially cover the outer periphery of the brush.

The fixing process may involve fixing the fixed end of the brush to the inner surface of the bottom wall of the holder with an adhesive, fixing the outer peripheral surface of the brush to the inner surface of the peripheral wall of the holder with an adhesive, and fixing the outer peripheral surface of a cylindrical protrusion protruding from the center of the bottom wall of the holder to the inner peripheral surface of the brush with an adhesive.

According to an embodiment of the present invention, it is possible to provide an abrasive brush whose wire is less likely to break and has good abrasive efficiency, and a method for manufacturing the same.

FIG. 1 is a perspective view showing an appearance of an abrasive brush according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of the abrasive brush of FIG. FIG. 3 is a schematic diagram for explaining a method of manufacturing the brush of FIG. FIG. 4 is a schematic diagram for explaining a method of manufacturing the brush of FIG. FIG. 5 is a schematic diagram for explaining a method of manufacturing the brush of FIG. FIG. 6 is a schematic diagram for explaining a method of manufacturing the brush of FIG. FIG. 7 is a bottom view of the brush of FIG. 2 as viewed from the free end side of the wire. FIG. 8 is a perspective view of the holder in FIG. 2 as viewed from the brush side. FIG. 9 is a cross-sectional view of the rib of the holder of FIG. 8 taken along line F9-F9.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIGS. 1 and 2 , an abrasive brush 100 according to one embodiment includes a brush 10 and a holder 20 .

The brush 10 is a bundle of multiple wires 2 in a cylindrical shape. When manufacturing the brush 10, for example, as shown in FIG. 3, one end 2a of multiple wires 2 (approximately 500 in this embodiment) of the same length are aligned on a flat surface S and bundled into a cylindrical shape, and as shown in FIG. 4, one end 2a of the multiple wires 2 are temporarily fixed to each other by welding to form a bundle 4. Then, as shown in FIG. 5, the fixed ends 4a of multiple bundles 4 (eight in this embodiment) are aligned on the flat surface S to arrange and collect multiple bundles 4 in a cylindrical shape, and the fixed ends 4a of these multiple bundles 4 are permanently fixed to each other by welding as shown in FIG. 6. This forms a cylindrical brush 10 having a circular fixed end 10a at one axial end.

The wire 2 of the brush ₁₀ is, for example, a nylon (polyamide) filament containing abrasive grains and having a diameter of about 0.1 mm. The abrasive grains are alumina ( _Al2O3 ), silicon carbide ( _SiO ), diamond powder, etc. The length of the wire 2 after welding is about 60 mm. The diameter of the bundle 4 of the multiple wires 2 is about 20 mm, and the outer diameter of the brush 10 formed by assembling the multiple bundles 4 into a cylindrical shape is about 70 mm, and the inner diameter of the brush 10 is about 30 mm. The axial length of the wire 2 of the brush 10 is about 60 mm.

When manufacturing the wire 2, for example, nylon and silicon carbide grit, or nylon and aluminum oxide are mixed and extruded into a brush filament. The sharp edges of the abrasive grains (grits) mixed into the nylon base material of the wire 2 are fixed randomly on all surfaces, so it has been confirmed that the wire 2 can reliably grip any shape of work surface and exhibit abrasive performance. Furthermore, the wire 2 used in the brush 10 of this embodiment is a resin wire containing abrasive grains with excellent heat resistance (melting point 217°C), and can withstand work in places where it is difficult to release frictional heat, such as work in narrow spaces, and can prevent welding to the contact surface. The type of abrasive grains to be mixed with the resin material can be selected from a large number of different coarsenesses. For example, it is possible to select from 12 types between #1000 (fine) and #46 (coarse).

In addition to welding, the means for fixing the ends 2a of the wires 2 can be, for example, adhesive. Similarly, in addition to welding, the means for fixing the fixed ends 4a of the bundles 4 can be, for example, adhesive.

The brush 10 is made by bundling multiple wires 2 into multiple bundles 4 and fixing their fixed ends 4a together, so there are almost no gaps between the wires 2 or between the bundles 4, as shown in Figure 7. In other words, the brush 10 has a structure in which the one ends 2a of multiple wires 2 (approximately 4,000 in this embodiment) of the same length are aligned and densely packed on a flat surface, and the one ends 2a of the multiple wires 2 are fixed together. Note that the wires 2 on the fixed end 4a side of the multiple bundles 4 cannot move against each other, but the free ends 2b on the side that contact the workpiece opposite the one end 2a of each wire 2 can move.

As shown in Figures 2 and 8, the holder 20 has an annular bottom wall portion 22 having an inner surface 22a facing the fixed end 10a of the brush 10, a cylindrical peripheral wall portion 24 continuous with the outer peripheral edge 22b of the bottom wall portion 22, and a substantially cylindrical protrusion portion 26 protruding coaxially with the peripheral wall portion 24 from the center of the inner surface 22a of the bottom wall portion 22. The holder 20 can be formed by integral molding using resin, or can be formed using a 3D printer. The holder 20 can be formed, for example, from ABS resin.

The inner diameter of the inner circumferential surface 24a of the peripheral wall portion 24 is slightly larger than the outer diameter of the fixed end 10a of the brush 10. The outer diameter of the outer circumferential surface 26a of the protruding portion 26 is slightly smaller than the inner diameter of the fixed end 10a of the brush 10. In this embodiment, the inner diameter of the peripheral wall portion 24 is set to about 70 mm, and the outer diameter of the protruding portion 26 is set to about 25 mm. The protruding height of the peripheral wall portion 24 from the bottom wall portion 22 is set to about 45 mm, and the protruding height of the protruding portion 26 from the inner surface 22a of the bottom wall portion 22 is set to about 15 mm.

The holder 20 has an annular recess 21 surrounded by the inner surface 22a of the bottom wall 22, the inner surface 24a of the peripheral wall 24, and the outer surface 26a of the protrusion 26. The brush 10 is fixed to the holder 20 with its fixed end 10a housed in the recess 21 of the holder 20 via an adhesive. In other words, the brush 10 is adhered to the inner surface 22a of the bottom wall 22 of the holder 20, the inner surface 24a of the peripheral wall 24, and the outer surface 26a of the protrusion 26 via an adhesive.

The peripheral wall portion 24 of the holder 20 has a plurality of slits 28a, 28b (ten in this embodiment) extending in the circumferential direction. The slits 28a, 28b are provided in two rows spaced apart in the axial direction of the peripheral wall portion 24. The plurality of slits 28a (28b) in each row (five in this embodiment) are lined up in the circumferential direction with ribs 29a (29b) between them. Each rib 29a, 29b is a part of the peripheral wall portion 24. Each slit 28a, 28b is provided penetrating the peripheral wall portion 24, connecting the inner peripheral surface 24a and the outer peripheral surface 24b of the peripheral wall portion 24.

The ribs 29a, 29b in each row are arranged in a staggered manner. That is, the ribs 29a in the row farthest from the bottom wall portion 22 are positioned to face the circumferential centers of the slits 28b in the row closer to the bottom wall portion 22. The ribs 29b in the row closer to the bottom wall portion 22 are positioned to face the circumferential centers of the slits 28a in the row farthest from the bottom wall portion 22. In this way, the rigidity of the peripheral wall portion 24 of the holder 20 is increased by arranging the ribs 29a, 29b in each row circumferentially offset.

In this embodiment, the circumferential length of each slit 28a, 28b is set to approximately 40 mm, and the axial width is set to approximately 8 mm. Also, in this embodiment, the circumferential width of each rib 29a, 29b is set to approximately 5 mm, and the axial length is set to approximately 8 mm.

The shape of each rib 29a, 29b is not rectangular, but is curved so that the end farther from the bottom wall 22 opens in the circumferential direction. In other words, the shape of each slit 28a, 28b is roughly rectangular with the corners farther from the bottom wall 22 at both ends in the circumferential direction rounded in an arc shape.

As shown in Fig. 9, the cross section of each rib 29b (29a) perpendicular to the axial direction is an isosceles triangle with a vertex at a point on the inner peripheral surface 24a of the peripheral wall portion 24. In other words, each rib 29a, 29b has two side surfaces 27 at the ends of two circumferentially adjacent slits 28a (28b) that converge from the edge of the slit 28a (28b) on the outer peripheral surface 24b side of the peripheral wall portion 24 toward the inner peripheral surface 24a.

By cutting the five ribs 29a in the row farthest from the bottom wall 22 of the peripheral wall 24, the axial length of the peripheral wall 24 of the holder 20 can be shortened by about 15 mm. In other words, the protruding height of the peripheral wall 24 of the holder 20 from the bottom wall 22 after cutting the five ribs 29a is about 30 mm.

The axial end of the ribs 29a farther from the bottom wall portion 22 is circumferentially expanded and widened, so the position at which each rib 29a is cut is not the axial end of the rib 29a farther from the bottom wall portion 22, but the end closer to the bottom wall portion 22. In this way, by cutting the end closer to the bottom wall portion 22 of each rib 29a, the axial end of the peripheral wall portion 24 opposite the bottom wall portion 22 after cutting can be made approximately flat.

By cutting the five ribs 29a in the row farthest from the bottom wall 22 of the peripheral wall 24 as described above, the amount of protrusion of the brush 10 from the end farthest from the bottom wall 22 of the peripheral wall 24 can be increased by approximately 15 mm. In other words, if the free end 2b of the wire 2 of the brush 10 becomes worn and shortened due to use of the abrasive brush 100, the amount of protrusion of the free end 2b of the wire 2 of the brush 10 can be restored to the same level as when it was first used by cutting the five ribs 29a of the holder 20 to shorten the axial length of the peripheral wall 24.

Furthermore, when the free end 2b of the wire 2 of the brush 10 wears down and becomes even shorter as a result of use of the abrasive brush 100, the axial length of the peripheral wall 24 of the holder 20 can be shortened by about 15 mm by cutting the five ribs 29b in the row closest to the bottom wall 22 of the peripheral wall 24, thereby further extending the service life of the abrasive brush 100. After the five ribs 29b are cut, the peripheral wall 24 of the holder 20 protrudes from the bottom wall 22 by about 15 mm. Because the holder 20 is made of resin, nippers that can be easily handled with one hand can be used to cut the ribs 29a, 29b, making the work easier.

When multiple slits 28a, 28b are provided in the peripheral wall portion 24 of the holder 20, the mechanical strength of the peripheral wall portion 24 is lower than when the slits 28a, 28b are not provided. For this reason, in this embodiment, the width of the end portion of each rib 29a, 29b farther from the bottom wall portion 22 is made wider to increase the mechanical strength of the peripheral wall portion 24. On the other hand, if the width of each rib 29a, 29b is made too wide, it becomes difficult to cut it easily with pliers, so the width of the end portion of each rib 29a, 29b closer to the bottom wall portion 22 is narrowed.

Similarly, by making the cross section of each rib 29a, 29b an isosceles triangle, the mechanical strength of the peripheral wall portion 24 is maintained to a certain extent and each rib 29a, 29b is easily cut with pliers. It is also possible to make the cross section of each rib 29a, 29b a shape that converges from the end of the inner peripheral surface 24a side of the two circumferentially adjacent slits 28a, 28b toward the outer peripheral surface 24b of the peripheral wall portion 24, but in order to improve the aesthetic appearance when the peripheral wall portion 24 is viewed from the outside, the cross section of each rib 29a, 29b is made a shape that converges toward the inner peripheral surface 24a.

The protruding portion 26 of the holder 20 has a mounting hole 32 through which a mounting shaft 30 is inserted to attach the abrasive brush 100 to an NC milling machine, a machining center, a grinding robot, or the like. The mounting hole 32 penetrates the bottom wall portion 22 and the protruding portion 26 of the holder 20 and is provided coaxially with the peripheral wall portion 24.

The mounting shaft 30 has a structure in which a regular hexagonal prism-shaped head 30b is integrally provided at one end of a cylindrical shaft portion 30a. The head 30b has an inscribed circle that is slightly larger than the diameter of the shaft portion 30a. The mounting hole 32 of the holder 20 has a circular cross-sectional insertion hole portion 32a that is large enough to insert the shaft portion 30a of the mounting shaft 30 but not large enough to insert the head 30b. The mounting hole 32 has a regular polygonal engagement recess 32b that is continuous with the insertion hole portion 32a at the end of the protruding side far from the bottom wall portion 22 of the protruding portion 26. The engagement recess 32b has a size slightly larger than the head 30b that can just accommodate the head 30b of the mounting shaft 30, and engages with the head 30b so as to prohibit rotation of the received head 30b.

The mounting shaft 30 has a pin hole 34 that penetrates the shaft portion 30a in the radial direction. The pin hole 34 is located slightly above the upper surface 40a of the spacer 40 when the abrasive brush 100 is assembled as shown in FIG. 1. When an R pin (snap pin, pine needle pin) 50 is attached to the pin hole 34 as shown in FIG. 1, the mounting shaft 30 is fixed to the abrasive brush 100, and the mounting shaft 30 cannot move axially or rotate relative to the abrasive brush 100. In other words, the mounting shaft 30 is fixed to the abrasive brush 100 only by the R pin 50, so that the mounting shaft 30 can be easily attached and detached from the abrasive brush 100.

The D-cut 42 of the spacer 40 is a structure for providing a space for inserting the tip of a tool such as pliers for clamping the R-pin 50 between the R-pin 50 and the bottom wall 22 of the holder 20 when the R-pin 50 is pulled out of the pin hole 34 of the mounting shaft 30 in the assembled state shown in FIG. 1. Therefore, the spacer 40 can be omitted by devising the shape of the R-pin 50. Also, if a holder with the spacer 40 integrated is used, there is no need to devise the shape of the R-pin 50. The D-cuts for inserting the tip of the tool may be provided at two radially spaced locations on the spacer 40, or the holder itself may be provided with D-cuts at two radially spaced locations.

A method for mounting the above-described abrasive brush 100 on the mounting shaft 30 will now be described.
First, the abrasive brush 100 is prepared by adhesively fixing the brush 10 to the recess 21 of the holder 20 as described above. Then, the shaft portion 30a of the mounting shaft 30 is inserted from inside the holder 20 into the mounting hole 32 of the protruding portion 26. At this time, the mounting shaft 30 is passed through a hole (where no wire 2 is present) in the center of the brush 10. The size of the hole in the center of the brush 10 is large enough to allow the head 30b of the mounting shaft 30 to be inserted therethrough. After the shaft portion 30a of the mounting shaft 30 is inserted into the mounting hole 32 of the holder 20, the head 30b of the mounting shaft 30 is fitted into the engagement recess 32b of the mounting hole 32.

Then, a spacer 40 is fitted onto the shaft portion 30a of the mounting shaft 30 protruding from the outer surface 22c of the bottom wall portion 22 of the holder 20, and an R-pin 50 is attached to the pin hole 34 on the upper surface 40a of the spacer 40. In this state (the state shown in FIG. 1), the mounting shaft 30 is fixed to the holder 20, and the mounting shaft 30 is prohibited from coming out of the holder 20 and from rotating.

The above-described abrasive brush 100 of the present embodiment is intended to be used by attaching it to a machine such as an NC milling machine, a machining center, or a grinding robot. In other words, the abrasive brush 100 with the brush 10 fixed to the holder 20 is attached and fixed to the mounting shaft 30 of the machine, and the mounting shaft 30 with the abrasive brush 100 attached is attached to the machine. The abrasive brush 100 of the present embodiment has multiple wires 2 parallel to the mounting shaft 30, which is the rotation shaft of the machine, and is used by abutting the free ends 2b of the multiple wires 2 perpendicularly to the polished surface of the workpiece. For this reason, the free ends 2b of the multiple wires 2 of the brush 10 gradually wear down and become shorter. The abrasive brush 100 of the present embodiment is suitable for use at a relatively slow rotation speed of, for example, 3000 rpm or less, and is suitable for use in cleanly removing minute burrs of about 0.1 mm to 0.5 mm on the processed surface of metal.

In the abrasive brush 100 of this embodiment, the wires 2 are packed tightly together in a cylindrical shape, so there are almost no gaps between the wires 2, and the fixed end 10a side of the brush 10 cannot move. In contrast, the free ends 2b of the wires 2 of the brush 10 can move slightly, but the outer peripheral surface of the brush 10 is held down over almost the entire axial length by the inner peripheral surface 24a of the peripheral wall portion 24 of the holder 20, and the fixed end 10a side of the inner peripheral surface of the brush 10 is held down by the outer peripheral surface 26a of the protruding portion 26 of the holder 20, so the free ends 2b of the wires 2 of the brush 10 cannot extend outside the peripheral wall portion 24 of the holder 20.

This allows the density of the wire 2 whose free end 2b comes into contact with the polished surface of the workpiece to be increased, and the number of wires 2 in contact per unit area of the polished surface to be increased. This increases the polishing efficiency of the polished surface, enabling effective polishing in a short period of time. In addition, because the free end 2b of the wire 2 comes into contact with the polished surface of the workpiece perpendicularly, the wire 2 is less likely to break, and the polishing performance can be maintained at a good level throughout the entire service life of the polishing brush 100.

In addition, the abrasive brush 100 of this embodiment is a brush 10 made of multiple bundled resin wires 2 fixed to a resin holder 20, so it can be disposed of as plastic waste after use. Conventional abrasive brushes, in which the wires are made of resin and the holder is made of metal, require the brush and holder to be separated and disposed of after use, which incurs costs, but the abrasive brush 100 of this embodiment can reduce disposal costs.

In addition, the abrasive brush 100 of this embodiment can shorten the axial length of the holder 20 simply by cutting a predetermined number of ribs 29a (29b) with pliers or the like, thereby extending the service life of the brush 10. In other words, the abrasive brush 100 of this embodiment can shorten the axial length of the peripheral wall portion 24 of the holder 20 in two stages, so that the amount of protrusion of the free end 2b of the wire 2 of the brush 10 can be returned to its initial value each time the peripheral wall portion 24 is shortened, and the service life of the abrasive brush 100 can be extended by approximately three times compared to when the peripheral wall portion 24 is not shortened.

The present invention is not limited to the above-described embodiment, and various modifications can be made in the implementation stage without departing from the gist of the invention. The embodiments may be implemented in appropriate combination, in which case the combined effects can be obtained. Furthermore, the above-described embodiment includes various inventions, and various inventions can be extracted by combinations selected from the multiple constituent elements disclosed. For example, if the problem can be solved and an effect can be obtained even if some constituent elements are deleted from all the constituent elements shown in the embodiment, the configuration from which the constituent elements are deleted can be extracted as an invention.

For example, in the above embodiment, the brush 10 is formed by closely packing together multiple bundles 4 of wires 2 of the same material, but this is not limiting, and the brush 10 may be formed by closely packing together bundles 4 of wires 2 of different materials. For example, the brush 10' may be formed by alternately arranging in a circular ring bundles 4' of wires 2' made of a material capable of effectively polishing coarse metal burrs and bundles 4 of wires 2 made of a material capable of effectively polishing fine burrs. By using this brush 10', coarse and fine burrs on the machined surface of the metal can be polished simultaneously, improving work efficiency.

2...wire, 2a...one end, 2b...free end, 4...bundle, 4a...fixed end, 10...brush, 10a...fixed end, 20...holder, 21...recess, 22...bottom wall, 22a...inner surface, 24...circumferential wall, 24a...inner surface, 24b...outer surface, 26...projection, 26a...outer surface, 27...side, 28a, 28b...slit, 29a, 29b...rib, 30...mounting shaft, 30a...shaft, 30b...head, 32...mounting hole, 32a...insertion hole, 32b...engagement recess, 34...pin hole, 40...spacer, 40a...upper surface, 42...D cut, 50...R pin, 100...polishing brush.

The abrasive brush according to one embodiment of the present invention has a cylindrical brush and a cylindrical holder. The brush is a bundle of multiple resin wires containing abrasive grains , each end of which is temporarily fixed by welding , and the bundle is assembled into a cylindrical shape with the fixed ends aligned on the same plane, and the fixed ends are fixed by welding. The holder is made of resin and has a circular bottom wall portion facing the fixed end of the brush, and a cylindrical peripheral wall portion that is continuous with the outer periphery of the bottom wall portion so that the free ends of the wires opposite the fixed end of the brush protrude and partially cover the outer periphery of the brush. The holder accommodates and fixes the fixed end side of the brush. The peripheral wall portion of the holder has multiple slits arranged in the circumferential direction with multiple ribs between them. The rib has two side surfaces that converge from the edges of two slits adjacent to both sides in the circumferential direction toward the inner periphery of the peripheral wall portion. The axial length of the peripheral wall portion can be shortened by cutting the multiple ribs.

The holder may further have a cylindrical protrusion protruding from the center of the bottom wall along the inner circumferential surface of the brush. The brush is fixed to the inner surface of the bottom wall of the holder, the inner circumferential surface of the peripheral wall on the bottom wall side, and the outer circumferential surface of the protrusion with an adhesive.

According to another embodiment of the present invention, a method for manufacturing an abrasive brush includes the steps of bundling a plurality of wires made of resin containing abrasive grains, aligning one end of the wires to the same plane and temporarily fixing the ends together by welding to form a wire bundle ; aligning the fixed ends of the plurality of bundles to the same plane, gathering them into a cylindrical shape, and welding and fixing the fixed ends of the bundles to each other to form a cylindrical brush ; and fixing the fixed end of the brush to the holder by placing the fixed end of the brush in a holder having a circular bottom wall portion facing the fixed end of the brush, and a cylindrical peripheral wall portion connected to the outer edge of the bottom wall portion so that the free ends of the wires opposite the fixed end of the brush protrude and partially cover the outer surface of the brush.

For example, in the above embodiment, the brush 10 is formed by closely gathering a plurality of bundles 4 each made of wires 2 of the same material, but the present invention is not limited to this. The brush 10 may be formed by closely gathering bundles 4 each made of wires 2 of different materials. For example, the brush 10' may be formed by alternately arranging in a circular ring a bundle 4' made of wires 2' made of a material capable of effectively polishing coarse metal burrs and a bundle 4 made of wires 2 made of a material capable of effectively polishing fine burrs. By using this brush 10', coarse and fine burrs on the machined surface of the metal can be polished at the same time, improving work efficiency.
The invention as described in the claims of the original application is set forth below.
[1]
a cylindrical brush in which a plurality of wires are bundled together and one end of the bundle is fixed together, the bundle being assembled into a cylindrical shape with the fixed ends aligned on the same plane, and the fixed ends are fixed together;
a holder having a circular bottom wall portion facing the fixed end of the brush, and a cylindrical peripheral wall portion continuing from the outer periphery of the bottom wall portion so as to partially cover the outer periphery of the brush by projecting a free end of the wire rod opposite the fixed end of the brush, the holder housing and fixing the fixed end side of the brush;
A polishing brush having
[2]
The holder further has a cylindrical protrusion protruding from the center of the bottom wall portion along an inner circumferential surface of the brush.
The abrasive brush according to [1].
[3]
The wire is made of a resin containing abrasive grains,
The bundle is formed by fixing one ends of a plurality of the wires to each other by welding,
The brush has a plurality of bundles of fixed ends fixed to each other by welding,
The holder is made of resin,
the brush is fixed to an inner surface of the bottom wall portion of the holder, an inner circumferential surface of the peripheral wall portion on the bottom wall portion side, and an outer circumferential surface of the protrusion portion by an adhesive.
The abrasive brush according to [2].
[4]
The peripheral wall portion of the holder has a plurality of slits arranged in a circumferential direction with a plurality of ribs interposed therebetween,
The rib has two side surfaces that converge from edges of the two slits adjacent to each other in the circumferential direction toward the inner circumferential surface of the peripheral wall portion,
By cutting the plurality of ribs, the axial length of the peripheral wall portion can be shortened.
The abrasive brush according to [3].
[5]
a step of bundling a plurality of wire rods made of resin containing abrasive grains, aligning one end of each wire rod in the same plane, and welding and fixing the one ends to each other to form a bundle of the wire rods;
a step of gathering the fixed ends of a plurality of the bundles into a cylindrical shape by aligning the fixed ends of the bundles on the same plane and fusing the fixed ends of the bundles together to form a cylindrical brush;
a step of placing the fixed end of the brush in a holder having a circular bottom wall portion facing the fixed end of the brush and a cylindrical peripheral wall portion connected to an outer periphery of the bottom wall portion so as to partially cover an outer periphery of the brush by projecting a free end of the wire rod opposite the fixed end of the brush, and fixing the brush and the holder;
A method for producing an abrasive brush having the above structure.
[6]
The fixing step includes: fixing the fixed end of the brush to the inner surface of the bottom wall of the holder with an adhesive; fixing the outer circumferential surface of the brush to the inner surface of the peripheral wall of the holder with an adhesive; and fixing the outer circumferential surface of a cylindrical protrusion protruding from the center of the bottom wall of the holder to the inner circumferential surface of the brush with an adhesive.
[5] A method for producing the abrasive brush described in [5].

Claims (6)

a cylindrical brush in which a plurality of wires are bundled together and one end of the bundle is fixed together, the bundle being assembled into a cylindrical shape with the fixed ends aligned on the same plane, and the fixed ends are fixed together;
a holder having a circular bottom wall portion facing the fixed end of the brush, and a cylindrical peripheral wall portion continuing from the outer periphery of the bottom wall portion so as to partially cover the outer periphery of the brush by projecting a free end of the wire rod opposite the fixed end of the brush, the holder housing and fixing the fixed end side of the brush;
A polishing brush having The holder further has a cylindrical protrusion protruding from the center of the bottom wall portion along an inner circumferential surface of the brush.
2. The abrasive brush of claim 1. The wire is made of a resin containing abrasive grains,
The bundle is formed by fixing one ends of a plurality of the wires to each other by welding,
The brush has a plurality of bundles of fixed ends fixed to each other by welding,
The holder is made of resin,
the brush is fixed to an inner surface of the bottom wall portion of the holder, an inner circumferential surface of the peripheral wall portion on the bottom wall portion side, and an outer circumferential surface of the protrusion portion by an adhesive.
3. The abrasive brush of claim 2. The peripheral wall portion of the holder has a plurality of slits arranged in a circumferential direction with a plurality of ribs interposed therebetween,
The rib has two side surfaces that converge from edges of the two slits adjacent to each other in the circumferential direction toward the inner circumferential surface of the peripheral wall portion,
By cutting the plurality of ribs, the axial length of the peripheral wall portion can be shortened.
4. The abrasive brush of claim 3. a step of bundling a plurality of wire rods made of resin containing abrasive grains, aligning one end of each wire rod in the same plane, and welding and fixing the one ends to each other to form a bundle of the wire rods;
a step of gathering the fixed ends of a plurality of the bundles into a cylindrical shape by aligning the fixed ends of the bundles on the same plane and fusing the fixed ends of the bundles together to form a cylindrical brush;
a step of placing the fixed end of the brush in a holder having a circular bottom wall portion facing the fixed end of the brush and a cylindrical peripheral wall portion connected to an outer periphery of the bottom wall portion so as to partially cover an outer periphery of the brush by projecting a free end of the wire rod opposite the fixed end of the brush, and fixing the brush and the holder;
A method for producing an abrasive brush having the above structure. The fixing step includes: fixing the fixed end of the brush to the inner surface of the bottom wall of the holder with an adhesive; fixing the outer circumferential surface of the brush to the inner surface of the peripheral wall of the holder with an adhesive; and fixing the outer circumferential surface of a cylindrical protrusion protruding from the center of the bottom wall of the holder to the inner circumferential surface of the brush with an adhesive.
A method for producing the abrasive brush according to claim 5.