JP2017055785A - Grinding and sweeping brush - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grinding and sweeping brush that can perform work to provide brushing processing in a pipe easily, is excellent in work efficiency, and suitable for accurate machining, and can increase economic efficiency.SOLUTION: In a grinding and sweeping brush 1, a base end part of a shaft body 3 is fixed to a metal case 11, a brush fixing part 4 is provided at the tip of the shaft body 3, and a brush body 5 is removably connected to the brush fixing part 4. The brush body 5 includes a connection part 13 removably connected to the brush fixing part 4, a brush hair bundle 14 bundling a plurality of brush hairs 14a made of abrasive grain containing resin filament, and a fixing part 16 for fixing an end part of a brush work part 15 formed of the brush hair bundle 14 to the connection part 13.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a polishing brush capable of performing brushing processing on an inner peripheral surface portion of a pipe including a cylindrical body made of metal or non-ferrous metal.

  In general, a rotating brush that has excellent polishing ability and a good finished surface can be used as a tool to polish and remove metal working surfaces and welds, and to polish and remove burrs and rust generated on metal surfaces. Many are used (refer patent document 1). However, this type of conventional rotating brush cannot perform brushing such as polishing, grinding, deburring, rust removal, and paint peeling on the inner peripheral surface of the metal pipe.

  Therefore, as an example of a brush that cleans the inside of a pipe, for example, a brush that has a brush body formed by bundling both ends of a plurality of wires around a triangular wire having a triangular cross-sectional shape of a piano wire has been developed. Yes. In this brush, a support shaft of a metal rod is disposed at the axial center portion of the brush body, and both ends of a plurality of wires each having a triangular line are bundled at both ends of the support shaft. An intermediate portion between both ends of each wire is curved radially in a direction away from the support shaft.

  When this brush is used, a brush body having a diameter substantially the same as the inner diameter of the pipe is inserted into the pipe, and the base end portion of the brush body is attached to an electric drill or the like and rotated. Alternatively, the brush body may be reciprocated in the axial direction of the pipe. Thereby, it has the structure which brushes to the internal peripheral surface part of a metal pipe by making the corner | angular part of the triangular wire of a brush contact and grind | in contact with the internal peripheral surface part of a metal pipe.

Japanese Patent Laid-Open No. 8-131258

  The conventional brush that cleans the inside of a pipe is shaped so that the triangular wire of the metal wire expands radially, so the outer diameter of the brush must be physically smaller than the inner diameter of the pipe. If you do not work. In order to facilitate the work, it is necessary to increase the clearance between the pipe inner diameter and the brush outer diameter. Therefore, it is difficult to make the brush uniformly contact the entire inner surface of the pipe in the inner surface processing of the pipe, and abundant experience is required to perform the processing evenly. Furthermore, since the corners of the triangular wire of the brush are in contact with the inner surface of the pipe, the contact portion between the inner surface of the pipe and the brush is a point contact, so that the work efficiency is low.

  In addition, the brush using the metal wire having the above-described conventional configuration cannot change the outer diameter of the brush. Furthermore, since there is a possibility that a lot of scratches may be made on the inner surface of the pipe after the insertion until the brush is inserted into the processing portion of the pipe, it is not suitable for precise processing and the demand is limited.

  Further, since the support shaft of the metal rod is arranged at the shaft center portion of the brush body, the brush body has high rigidity, and for example, inner surface processing of a pipe such as a curved curved pipe cannot be performed.

  The present invention has been made paying attention to the above circumstances, and its purpose is to easily perform a brushing process in a pipe, to have high work efficiency, to be suitable for precise processing, and to improve economic efficiency. It is to provide a brushing brush that can.

In one aspect of the present invention, a base end portion of a shaft body is fixed to a base portion, a brush fixing portion is provided at a tip portion of the shaft body, and a brush body is detachably connected to the brush fixing portion. A brush for brushing, wherein the brush main body is detachably connected to the brush fixing portion, a brush hair bundle in which a plurality of brush hairs made of resin filaments containing abrasive grains are bundled, and the brush hair bundle And a fixing portion for fixing an end portion of the brush working portion formed by the step to the connecting portion.
In the polishing brush having the above-described configuration, after the brush working portion is inserted into the pipe, the brush working portion is mainly brushed by rotating the brush working portion. At this time, by rotating the brush working part at high speed, the brush bristle bundle of the brush working part can be expanded in the radial direction of the pipe by centrifugal force, and the bristle is brought into contact with the entire inner peripheral surface part of the pipe. be able to. As a result, brushing such as polishing, grinding, deburring, rust removal, and paint peeling on the inner peripheral surface of the pipe can be easily performed. Further, the brush main body is detachably connected to the brush fixing portion of the shaft body so that the brush main body can be exchanged and used.

Preferably, the brush working unit is in a first form in which the plurality of brush bristles are held in an unconstrained state in which the plurality of brush bristles can be freely moved, or in a constrained state in which the plurality of brush bristles are bent in a U shape. It has either one of the 2nd forms to hold | maintain.
Preferably, the fixing portion includes a bottomed cylindrical case, and the case includes a caulking fixing portion that caulks and fixes the end portions of the bristles.
Preferably, the shaft body is either one of a hard resin rod having high rigidity or a flexible shaft body in which a wire material that can be elastically deformed is arranged inside a soft resin pipe having high flexibility.
Preferably, the hard resin rod has one or a plurality of connecting members that are detachably connectable in the axial direction of the shaft body.

  ADVANTAGE OF THE INVENTION According to this invention, the operation | work which performs a brushing process in a pipe can be performed easily, and it can provide the polishing brush which has high work efficiency, is suitable for a precise process, and can improve economical efficiency. .

BRIEF DESCRIPTION OF THE DRAWINGS The longitudinal cross-sectional view which shows schematic structure of the whole polishing brush of the 1st Embodiment of this invention. An example of the use state of the scouring brush of 1st Embodiment is shown, (A) is a longitudinal cross-sectional view of the principal part which shows the state which inserted the scouring brush in the inside of a pipe, (B) is (A) IIB-IIB sectional view taken on the line of FIG. The longitudinal cross-sectional view of the principal part which shows another example of the use condition of the polishing brush of 1st Embodiment. The longitudinal cross-sectional view of the principal part which shows the use condition which inserts the polishing brush of FIG. 3 in the horizontal hole of the side surface of a pipe, and removes a crossing burr | flash. The longitudinal cross-sectional view which shows the schematic structure of the whole polishing brush of the 2nd Embodiment of this invention. The side view which shows the modification of the shaft body of the polishing brush of 2nd Embodiment with a part in cross section. The longitudinal cross-sectional view which shows the modification of the brush main body of a brushing brush.

[First Embodiment]
(Constitution)
1 and 2 show a first embodiment of the present invention. FIG. 1 is a longitudinal sectional view showing a schematic configuration of the entire polishing brush 1, and FIGS. 2A and 2B show an example of a usage state of the polishing brush 1. FIG. FIG. 2B is a cross-sectional view taken along the line IIB-IIB in FIG. 2A, showing a state in which the brush 1 is inserted into the metal pipe 2 to be processed.

  The polishing brush 1 of the present embodiment is a tool that can perform brushing processing on the inner peripheral surface portion of a metal pipe 2 including a cylindrical body such as a metal to be processed or a non-ferrous metal. As shown in FIG. 1, the brush 1 has a shaft body 3, a brush fixing portion 4, and a brush body 5.

  The shaft body 3 of this embodiment is a flexible shaft body 6 having flexibility. In this flexible shaft body 6, an elastically deformable wire 8 is disposed inside a soft resin pipe 7 having high flexibility. The soft resin pipe 7 is made of, for example, vinyl chloride. For example, a piano wire is used as the wire 8.

  The base end portion (lower end portion in FIG. 1) of the wire 8 is fixed in a state of being embedded in the center of a columnar first block member 9 made of a hard resin having high rigidity. The distal end portion of the wire 8 is fixed in a state of being embedded in the center on the proximal end side of the cylindrical second block member 10 made of a hard resin having high rigidity.

  Further, the base end portion of the soft resin pipe 7 is fixed in a state of being fitted on the first block member 9. Similarly, the distal end portion of the soft resin pipe 7 is fixed in a state of being fitted on the second block member 10. Thereby, the flexible shaft 6 in which the soft resin pipe 7 and the wire 8 are integrated is formed.

  A base end portion of the flexible shaft body 6 is fixed to a metal case (base portion) 11. The metal case 11 has a bottomed cylindrical case body 11a and a round bar shaft 11c fixed to the bottom 11b of the case body 11a. The case main body 11 a of the metal case 11 has a caulking fixing portion 11 d for caulking and fixing the base end portion of the flexible shaft body 6.

  A screw hole 10 a is formed in the central portion of the tip of the second block member 10. A male screw portion 12 of the brush body 5 described later is screwed into the screw hole 10a. And the brush fixing | fixed part 4 with which the brush main body 5 is connected so that attachment or detachment is possible by the 2nd block member 10 is formed.

  The brush body 5 is formed by a connecting portion 13 detachably connected to the brush fixing portion 4, a brush hair bundle 14 in which a plurality of brush hairs 14 a made of abrasive-containing resin filaments are bundled, and a brush hair bundle 14. A fixing unit 16 that fixes the end of the brush working unit 15 to the connecting unit 13.

  The brush bristles 14a are made of resin filaments containing abrasive grains formed of a resin material such as “N-GRIT” or “Negrit” (registered trademark) obtained by processing nylon and abrasive grains (grit) as filaments for brushes.

  The material of the brush bristles 14a of this embodiment is obtained by mixing nylon and silicon carbide grit or nylon and aluminum ocside and extruding them as brush filaments. This bristle 14a has a sharp edge of grit mixed in the base material nylon, which is randomly fixed on every surface, so it can capture any shape of work surface and exhibit polishing performance. It has been confirmed. Furthermore, the bristles 14a of this embodiment are resin wires with abrasive grains excellent in heat resistance (melting point 217 ° c), and can withstand work in places where it is difficult to release frictional heat such as narrow work, Welding to the contact surface can be prevented.

  The fixing part 16 has a case 17 that fixes one end of the bristle bundle 14. The case 17 has a bottomed cylindrical case main body 17a and a male screw portion 12 fixed to the bottom 17b of the case main body 17a. A connecting portion 13 that is detachably connected to the brush fixing portion 4 is formed by the male screw portion 12.

  The cylindrical portion of the case body 17a has a fixing portion 17c that fixes one end portion of the bristle bundle 14 with an adhesive. In the present embodiment, the case 17 is formed of, for example, a hard resin pipe having high rigidity, for example, ABS resin. The case 17 may be a material other than the hard resin pipe, for example, a metal material. In this case, one end portion of the bristle bundle 14 can be caulked and fixed to the fixing portion 17c of the case body 17a.

  The brush working part 15 is formed by a protruding part of the bristle bundle 14 that protrudes from the cylindrical part of the case body 17a. The bristle bundle 14 arranged in the protruding portion is held in a first form in which a plurality of bristle bristles 14a are held in an unconstrained state in which they can freely move. Therefore, in the brush working unit 15 of the present embodiment, the plurality of brush hairs 14a can be freely moved.

(Function)
Next, the operation of the polishing brush 1 having the above configuration will be described. When the polishing brush 1 according to the present embodiment is used, it is set so that the male screw portion 12 of the brush body 5 is screwed into the screw hole 10 a of the brush fixing portion 4 of the flexible shaft 6. The brush body 5 is prepared in advance with a plurality of types of parts having different sizes, shapes, and the like. And according to the conditions of the metal pipe 2 to be processed, it can be selectively used as appropriate.

  After the brush body 5 is set on the flexible shaft 6, as shown in FIG. 2A, the polishing brush 1 is inserted from the opening end on one end side of the metal pipe 2 to be processed. At this time, the brush 1 is inserted from the brush working unit 15 side of the brush 1 into the opening end on one end side of the metal pipe 2. Note that the outer diameter of the brush working portion 15 of the polishing brush 1 used at this time is preferably smaller than the inner diameter of the metal pipe 2.

  After the brush working unit 15 is inserted into the metal pipe 2, the brush working unit 15 is mainly rotated to perform a brushing process on the metal pipe 2. Thereby, it is possible to easily perform brushing processing such as polishing, grinding, deburring, rust removal, paint peeling, and the like on the inner peripheral surface portion of the metal pipe 2. The brush working unit 15 can be reciprocated in the axial direction.

  Further, when the brush working unit 15 is rotated at a high speed of, for example, about 8000 rpm, the brush bristles 14 of the brush working unit 15 are moved by the centrifugal force of the pipe 2 as shown in FIGS. It can be expanded in the radial direction. At this time, each bristle 14a of the bristle bundle 14 spreads radially from the end surface position of the connecting portion with the case body 17a. As a result, the portion of the protruding portion of the bristle bundle 14 on the protruding end side of each bristle 14 a is elastically deformed so as to be in line contact with the inner peripheral surface portion 2 a of the pipe 2. Therefore, the brush bristles 14 a can be brought into contact with the entire inner peripheral surface portion 2 a of the metal pipe 2. Thereby, it is possible to easily perform brushing processing such as polishing, grinding, deburring, rust removal, paint peeling, etc., on the inner peripheral surface portion 2a of the metal pipe 2.

(effect)
Therefore, the polishing brush 1 having the above configuration has the following effects. That is, in the polishing brush 1 of the present embodiment, the brush bristles 14 in which a plurality of brush bristles 14a made of abrasive resin filaments are bundled are provided, and the brush work is performed by the protruding portion protruding from the end of the case body 17a. Part 15 is formed. The brush bristles 14 a can be brought into contact with the entire inner peripheral surface 2 a of the metal pipe 2 by rotating the brush working unit 15 at a high speed of about 8000 rpm, for example. Thereby, it is possible to easily perform brushing processing such as polishing, grinding, deburring, rust removal, paint peeling, etc. on the inner peripheral surface portion 2a of the metal pipe 2.

  Moreover, in this embodiment, the brush fixing | fixed part 4 is provided in the front-end | tip part of the flexible shaft 6, and the brush main body 5 is connected to this brush fixing | fixed part 4 so that attachment or detachment is possible. Therefore, for example, when the brush bristles 14a of the brush working unit 15 are worn, only the brush body 5 can be replaced and used, so that the economy can be improved.

  Further, since the fixing portion 16 of the brush body 5 of the scouring brush 1 to be inserted into the metal pipe 2 to be processed and the soft resin pipe 7 of the flexible shaft 6 are formed of a resin material, the brush working portion 15 It is possible to prevent the parts other than the processed part from being damaged during the rotation.

  Further, in the present embodiment, by using the polishing brush 1 in which the outer diameter of the brush working unit 15 is smaller than the inner diameter of the metal pipe 2, the operation of inserting the polishing brush 1 into the metal pipe 2 is simplified. Can be done. Furthermore, by rotating the brush working unit 15 at a high speed of about 8000 rpm, for example, the brush bristle bundle 14 of the brush working unit 15 can be expanded in the radial direction of the pipe 2 by centrifugal force. Thereby, the side part of the protrusion part side of each bristle 14a of the protrusion part of the bristle bundle 14 is elastically deformed into a state in line contact with the inner peripheral surface part 2a of the pipe 2. At this time, a wide range of the inner peripheral surface portion 2a of the pipe 2 can be brushed by a side surface portion of each brush bristle 14a that is elastically deformed so as to be in line contact with the inner peripheral surface portion 2a of the pipe 2, and the work efficiency of the brushing processing is improved. Can be increased.

  Further, by increasing the brush rotation speed of the brush working unit 15, the brush bristle bundle 14 of the brush working unit 15 spreads radially by centrifugal force, so that the pipe 2 having a large inner diameter can be processed. At this time, since the tip of the brush working portion 15 greatly expands in proportion to the length of the brush working portion 15, the single polishing brush 1 can be adapted to many pipes 2 having an inner diameter size, which is economical. Is greatly improved.

  In the polishing brush 1 of the present embodiment, the flexible shaft 6 is formed by the soft resin pipe 7 having high flexibility and the elastically deformable wire 8, so that the flexibility of the polishing brush 1 is increased. Can do. Therefore, since the whole main body of the polishing brush 1 can be curved, the inner peripheral surface of the curved metal pipe can be brushed.

  Therefore, the brushing process can be easily performed without performing the etching process on the inner peripheral surface of the curved metal pipe, which is conventionally performed by the etching process using the chemical. As a result, great economic effects such as cost reduction of the entire apparatus can be obtained.

  Further, as shown in FIGS. 2A and 2B, when the lateral hole 21 is opened from the outside on the side surface of the metal pipe 2 as a workpiece, the edge of the opening of the lateral hole 21 of the metal pipe 2 is surely formed. A cross burr 22 projecting to the inside of the pipe 2 is formed. The cross burr 22 protruding from the edge of the opening of the horizontal hole 21 toward the inside of the pipe 2 can also be scraped and removed by the brush working portion 15 of the polishing brush 1 of the present embodiment.

  Further, as shown in FIG. 3, even if the brush working portion 15 of the polishing brush 1 of the present embodiment is inserted from the outside of the opening portion of the side hole 21 on the side surface of the metal pipe 2 which is a workpiece, high rotation is given. Good. Also in this case, as shown in FIG. 4, each bristle 14a of the brush working unit 15 spreads radially, so that each brush bristle 14a of the brush working unit 15 is directly entangled with the cross burr 22 by being pulled out while rotating. The cross burr 22 can be scraped and removed. Further, scraping scraps of the cross burr 22 can be removed outside the metal pipe 2 while being attached to the brush bristles 14a when the brush working unit 15 is pulled out from the opening of the lateral hole 21 after the work.

As an example of work of this embodiment,
(1) Material (S48C) crankshaft inner diameter tolerance deburring and polishing (2) Material (FC material) camshaft inner diameter tolerance deburring and polishing (3) Material (FCD material) power steering gear case parts Internal deburring (4) Internal deburring of piston of material (ADC12), Polishing (5) Internal diameter tolerance deburring of transmission of material (ADC12), Internal deburring of polishing (6) Hydraulic valve of material (FGD450), Polishing (7) Deburring the inner diameter of the air cylinder of the material (ADC12), polishing (8) Inner diameter polishing of various metal pipes of the material (SUS, aluminum, iron).

[Second Embodiment]
(Constitution)
FIG. 5 shows a second embodiment of the present invention. The present embodiment is a modification in which the configuration of the polishing brush 1 according to the first embodiment (see FIGS. 1 and 2) is changed as follows. 5, the same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals, and the description thereof is omitted.

  In the polishing brush 31 of the present embodiment, the shaft body 3 is formed of a hard resin rod 32 having high rigidity, for example, ABS resin. A screw hole 33 is formed in the central portion of the distal end portion of the hard resin rod 32. The male screw portion 12 of the brush body 5 is screwed into the screw hole 33. And the brush fixing | fixed part 34 with which the brush main body 5 is detachably connected by the screw hole 33 of the hard resin rod 32 is formed.

(Function)
Next, the operation of the above configuration will be described. When the polishing brush 31 of the present embodiment is used, the brush working unit 15 is rotated at a high speed of about 8000 rpm, for example, with the polishing brush 31 inserted into the metal pipe 2. Thereby, the bristle bundle | flux 14 of the brush operation | work part 15 can be expanded in the radial direction of the pipe 2 with a centrifugal force. Therefore, the side surface portion of the protruding portion of the bristle bundle 14 on the protruding end side of each bristle 14 a is elastically deformed so as to be in line contact with the inner peripheral surface portion 2 a of the pipe 2. At this time, a wide range of the inner peripheral surface portion 2a of the pipe 2 can be brushed by a side surface portion of each brush bristle 14a that is elastically deformed so as to be in line contact with the inner peripheral surface portion 2a of the pipe 2, and the work efficiency of the brushing processing is improved. Can be increased.

(effect)
Therefore, the same effect as that of the polishing brush 1 of the first embodiment can be obtained with the polishing brush 31 of the present embodiment. Furthermore, in this embodiment, the brush main body 5 is detachably connected to the hard resin rod 32 by screwing the male screw portion 12 of the brush main body 5 into the screw hole 33 of the hard resin rod 32. Therefore, the brush body 5 having an appropriate size can be appropriately and selectively used according to the conditions of the metal pipe 2 to be processed. Further, for example, when the brush bristles 14a of the brush working unit 15 are worn, only the brush body 5 can be replaced and used, so that the economy can be improved.

[Modification]
(Constitution)
FIG. 6 is a side view showing a modified example of the shaft body 3 of the polishing brush 31 of the second embodiment. In this modification, a connecting member 41 that can be detachably connected to the hard resin rod 32 of the second embodiment is provided. The connecting member 41 of this modification is formed with a screw hole portion 43 at the distal end portion (upper end portion in FIG. 6) of the hard resin rod 42 and a male screw portion 44 at the proximal end portion (lower end portion in FIG. 6). Yes. The male screw portion 44 is screwed into the screw hole 33 of the hard resin rod 32 so that the connecting member 41 is detachably connected to the hard resin rod 32. Further, the male threaded portion 12 of the brush body 5 of the polishing brush 31 is screwed into the screw hole 43 of the connecting member 41, so that the connecting member 41 is detachably connected to the brush body 5 of the polishing brush 31. Is done.

  In this modification, the length of the shaft body 3 of the polishing brush 31 can be increased by detachably connecting the connecting member 41 to the hard resin rod 32. The number of connecting members 41 is not limited to one, and a plurality of connecting members 41 may be connected in series in the axial direction of the shaft body 3. The length of the shaft body 3 of the polishing brush 31 can be adjusted as appropriate according to the number of connections of the connecting members 41.

  FIG. 7 is a longitudinal sectional view of a main part showing a modification of the brush body 5 of the scouring brush 1 of the first embodiment. The brush main body 5 of the present modification is provided with a brush working unit 51 of a second form that holds a plurality of brush bristles 14a in a U-shaped constrained state. In the brush working unit 51 of the present embodiment, the protruding portion of the bristle bundle 14 protruding from the cylindrical portion of the case body 17a is bent in a U shape.

  The same effect as that of the polishing brush 1 of the first embodiment can be obtained with the polishing brush 1 of this modification. Further, in the second embodiment of the brush working unit 51 that is held in a U-shaped constrained state, the brush bristles of the brush working unit 51 jump out of the opening of the lateral hole 21 on the side surface of the metal pipe 2 during the work. There is nothing. Therefore, it is possible to efficiently remove the cross burr.

  The shape of the brush working unit is the same as that of the brush 1 of the first embodiment. The brush working unit 15 of the first embodiment that holds the plurality of brush bristles 14a in an unconstrained state that can be freely moved. Moreover, it is not limited to the brush working part 51 of the 2nd form which hold | maintains the bristle bundle | flux 14 in the restraint state bent in U shape like the said modification. Any shape can be produced depending on the location of use.

  Furthermore, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention. For example, the type of abrasive grains to be mixed with the resin material can be appropriately selectively selected according to the target portion.

    DESCRIPTION OF SYMBOLS 1 ... Polishing brush, 2 ... Metal pipe, 2a ... Inner peripheral surface part, 3 ... Shaft body, 4 ... Brush fixing part, 5 ... Brush main body, 6 ... Flexible shaft body, 7 ... Soft resin pipe, 8 ... Wire rod , 9 ... 1st block member, 10 ... 2nd block member, 10a ... Screw hole, 11 ... Metal case (base part), 11a ... Case main body, 11b ... Bottom part, 11c ... Shaft part, 11d ... Fixing part, 12 44 ... male screw part, 13 ... connecting part, 14 ... brush hair bundle, 14a ... brush hair, 15 ... brush working part, 16 ... fixing part, 17 ... case, 17a ... case main body, 17b ... bottom part, 17c ... fixing part , 21 ... side hole, 22 ... cross burr, 31 ... scouring brush, 32 ... hard resin rod, 33, 43 ... screw hole, 34 ... brush fixing part, 41 ... connecting member, 51 ... brush working part.

Claims (5)

A polishing brush in which a base end portion of a shaft body is fixed to a base portion, a brush fixing portion is provided at a tip portion of the shaft body, and a brush body is detachably connected to the brush fixing portion,
The brush body is
A connecting part detachably connected to the brush fixing part;
A bristles bundling a plurality of bristles made of resin filaments containing abrasive grains,
A fixing portion for fixing an end portion of a brush working portion formed by the brush hair bundle to the connecting portion;
A polishing brush comprising:   The brush working unit holds the plurality of brush bristles in a first state that holds each of the bristles in an unconstrained state that can be freely moved, or holds the plurality of brush bristles in a constrained state that is bent in a U shape. The polishing brush according to claim 1, which has one of two forms. The fixed portion has a bottomed cylindrical case,
The polishing brush according to claim 1 or 2, wherein the case has a caulking fixing portion that integrally caulks and fixes the end portion of the brush bristle bundle.   The shaft body is either one of a hard resin rod having high rigidity or a flexible shaft body in which an elastically deformable wire is disposed inside a soft resin pipe having high flexibility. Item 4. The polishing brush according to any one of Items 1 to 3.   The polishing brush according to claim 4, wherein the hard resin rod has one or a plurality of connecting members that are detachably connectable in an axial direction of the shaft body.