JP7687938B2 - polishing tool - Google Patents

Description

The present invention relates to a polishing tool, and in particular to a polishing tool for polishing the inner wall surface of a tube.

Patent Document 1 discloses a polishing tool equipped with an abrasive body. The abrasive body is discretely attached to a thread-like core material made of synthetic resin. While an abrasive grain slurry, in which abrasive grains are dispersed in water, is flowed inside the metal pipe, the polishing tool is inserted into the inside of the metal pipe and the core material is pulled to polish the inner surface of the metal pipe.

JP 2019-188523 A

The present inventors have discovered the following problems.
When such an abrasive tool is used to polish the inner wall surface of a pipe, the abrasive tool is inserted into the inside of the pipe while an abrasive slurry is flowing inside the pipe. The multiple abrasive bodies located on the upstream side may retain only the abrasive grains from the abrasive slurry. This removes the abrasive grains from the abrasive slurry, leaving only water. The abrasive body located downstream is supplied with water, but receives almost no abrasive grains. As a result, the distribution of the abrasive grains in the pipe becomes uneven. There is a risk that parts of the pipe where there is a shortage of abrasive grains may not be polished sufficiently.

In view of the above problems, the present invention aims to provide a polishing tool that prevents uneven distribution of abrasives in a tube.

The polishing tool according to the present invention comprises:
A polishing tool for polishing an inner wall surface of a pipe,
A first clamping unit;
A second clamping portion;
a plurality of polishing bodies disposed between the first clamping portion and the second clamping portion and clamped between the first clamping portion and the second clamping portion;
A proximity means (e.g., strings 4, 5, etc.) for bringing the first and second clamping parts closer to each other;
A capsule containing an abrasive;
The capsules are disposed between the plurality of abrasive bodies.

With this configuration, the first and second clamping parts are brought close to each other, and the multiple polishing bodies press against the capsule. This pressure breaks the capsule, releasing the polishing agent outside the capsule. This allows the polishing agent to be supplied between the multiple polishing bodies. This prevents the polishing agent from being distributed unevenly in the tube.

The present invention can prevent uneven distribution of abrasives in the tube.

1 is a schematic cross-sectional view showing an example of a grinding tool according to a first embodiment. 3 is a schematic cross-sectional view showing one step of a polishing method using an example of the polishing tool according to embodiment 1. FIG.

Specific embodiments to which the present invention is applied will be described in detail below with reference to the drawings. However, the present invention is not limited to the following embodiments. In addition, the following descriptions and drawings have been simplified as appropriate for clarity of explanation.

(Embodiment 1)
A first embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic cross-sectional view showing an example of a grinding tool according to the first embodiment.

Naturally, the right-handed xyz coordinate system shown in FIG. 1 and other drawings is for the convenience of explaining the positional relationships of the components. Normally, the z-axis is directed vertically upward, and the xy plane is the horizontal plane, which is common between all drawings.

As shown in FIG. 1, the polishing tool 10 includes a first clamping portion 1, a second clamping portion 2, a plurality of polishing bodies 3, strings 4 and 5, and a capsule 6. The polishing tool 10 can be used to polish the inner wall surface W1a of a pipe W1, which is the object to be polished.

The first clamping portion 1 and the second clamping portion 2 clamp a plurality of polishing bodies 3. The first clamping portion 1 and the second clamping portion 2 may have a size and mechanical strength required for clamping the polishing bodies 3. The first clamping portion 1 and the second clamping portion 2 may have a variety of shapes. An example of the first clamping portion 1 and the second clamping portion 2 shown in FIG. 1 is two plate-shaped bodies. The first clamping portion 1 may have a hole 1a through which the string 4 can pass. The second clamping portion 2 may have a hole 2a through which the string 5 can pass.

The plurality of polishing bodies 3 are disposed between the first clamping portion 1 and the second clamping portion 2. The plurality of polishing bodies 3 are clamped between the first clamping portion 1 and the second clamping portion 2. The plurality of polishing bodies 3 may each have a size that allows them to pass through the tube W1. Specifically, the diameter D3 of each of the plurality of polishing bodies 3 may be smaller than the inner diameter D1 of the tube W1. When the polishing body 3 receives a predetermined compressive stress, it may deform so as to protrude in a vertical direction relative to the compressive stress. The polishing body 3 may be made of a material having a deformable property. The polishing body 3 may be made of a material having mechanical strength and hardness required for polishing the object to be polished. Examples of such materials include elastic materials such as rubber. Such elastic materials may contain an abrasive. When the tube W1 is made of a metal material, the polishing body 3 may be made of an elastic material such as rubber.

The polishing body 3 has a hole 3a, which penetrates the polishing body 3. The hole 3a should have a cross-sectional area large enough to allow the strings 4 and 5 to pass through at the same time. An example of the polishing body 3 shown in Figures 1 and 2 is three. The polishing body 3 can have a variety of shapes. An example of the polishing body 3 shown in Figures 1 and 2 is spherical. The polishing bodies 3 shown in Figures 1 and 2 are arranged in a row between the first clamping portion 1 and the second clamping portion 2.

The total length of the string 4 is preferably longer than the length L1 of the tube W1. One end 4a of the string 4 is attached to the second clamping unit 2. The string 4 passes through the holes 3a of the multiple polishing bodies 3. An example of the string 4 shown in Figures 1 and 2 passes through all the holes 3a of the three spherical bodies, which are an example of the multiple polishing bodies 3. The string 4 passes through the side of the capsule 6 or its vicinity between the multiple polishing bodies 3. If the first clamping unit 1 has a hole 1a, the string 4 may pass through the hole 1a. The first clamping unit 1 is disposed between the one end 4a and the other end 4b of the string 4. When the other end 4b of the string 4 is pulled so as to be separated from the multiple polishing bodies 3, the one end 4a of the string 4 pulls the second clamping unit 2 toward the multiple polishing bodies 3. This brings the second clamping unit 2 closer to the first clamping unit 1.

The total length of the string 5 is preferably longer than the length L1 of the tube W1. One end 5a of the string 5 is attached to the first clamping unit 1. The string 5 passes through the holes 3a of the multiple polishing bodies 3. An example of the string 5 shown in Figures 1 and 2 passes through all the holes 3a of the three spherical bodies, which are examples of the multiple polishing bodies 3. The string 5 passes through the side of the capsule 6 or its vicinity between the multiple polishing bodies 3. If the second clamping unit 2 has a hole 2a, the string 5 may pass through the hole 2a. The second clamping unit 2 is disposed between the one end 5a and the other end 5b of the string 5. When the other end 5b of the string 5 is pulled so as to be separated from the multiple polishing bodies 3, the one end 5a of the string 5 pulls the first clamping unit 1 toward the multiple polishing bodies 3. This brings the first clamping unit 1 closer to the second clamping unit 2.

String 4 and string 5 function as a technical proximity means for bringing first clamping portion 1 and second clamping portion 2 closer together.

The capsule 6 contains the abrasive 7. An example of the capsule 6 shown in FIG. 1 is a cylindrical or box-shaped body. The capsule 6 is disposed between the multiple polishing bodies 3. The capsule 6 may be disposed between all of the multiple polishing bodies 3. When the capsule 6 receives a predetermined compressive stress, the capsule 6 breaks and the abrasive 7 is released to the outside of the capsule 6. The abrasive 7 is preferably at least smaller than the polishing body 3. The abrasive 7 is preferably a plurality of polishing grains made of a material having the mechanical strength and hardness required for polishing the object to be polished.

(polishing method)
Next, a polishing method for polishing the inner wall surface W1a of the pipe W1 to be polished using the polishing tool 10 will be described with reference to Figures 1 and 2. Figure 2 is a schematic cross-sectional view showing one step of the polishing method using the polishing tool 10 shown in Figure 1.

As shown in FIG. 1, the polishing tool 10 is inserted into the pipe W1, and the polishing body 3 is placed near the inner wall surface W1a of the pipe W1 (step ST1). The polishing tool 10 may be inserted into the pipe W1 while extending in the axial direction of the pipe W1 (here, the X-axis direction) while keeping the polishing body 3 separated from the inner wall surface W1a of the pipe W1. Specifically, the polishing tool 10 is inserted into the pipe W1 while one of the strings 4 and 5 is placed outside the pipe W1. By flowing a fluid, the other of the strings 4 and 5 is passed through the downstream opening of the pipe W1 and is brought out to the outside of the pipe W1. For example, water can be used as the fluid.

2, the first clamping portion 1 and the second clamping portion 2 are brought close to each other, and the polishing body 3 is deformed, so that the polishing body 3 and the inner wall surface W1a of the tube W1 come into contact (step ST2). Specifically, the other end 4b of the string 4 is pulled so as to separate it from the multiple polishing bodies 3, and the other end 5b of the string 5 is pulled so as to separate it from the multiple polishing bodies 3. As a result, the first clamping portion 1 and the second clamping portion 2 are brought close to each other. The first clamping portion 1 and the second clamping portion 2 apply compressive stress to the multiple polishing bodies 3, and the multiple polishing bodies 3 press against the capsule 6. This pressure breaks the capsule 6, and the polishing agent 7 is released outside the capsule 6. It is preferable that the portion where the capsule 6 is broken is a portion facing the inner wall surface W1a of the tube W1, so that the polishing agent 7 moves to the inner wall surface W1a of the tube W1. The abrasive 7 moves between the multiple polishing bodies 3 to the inner wall surface W1a of the pipe W1. At least one of the polishing bodies 3 and the abrasive 7 comes into contact with the inner wall surface W1a of the pipe W1. Furthermore, by moving the polishing tool 10 in the pipe W1, the inner wall surface W1a of the pipe W1 can be polished.

As a result, the abrasive 7 can be supplied between the multiple polishing bodies 3. This prevents the distribution of the abrasive 7 in the tube W1 from becoming uneven. This allows the abrasive 7 to be distributed uniformly throughout the multiple polishing bodies 3 in the tube W1. As a result, most of the area of the inner wall surface W1a of the tube W1 can be polished uniformly.

When the first clamping portion 1 and the second clamping portion 2 apply compressive stress to the multiple polishing bodies 3 and at least one of the multiple polishing bodies 3 deforms to bulge in a direction perpendicular to the compressive stress, the diameter D3 of the polishing body 3 increases. When the polishing agent 7 is placed between the polishing body 3 and the inner wall surface W1a of the tube W1, the polishing agent 7 comes into contact with the inner wall surface W1a of the tube W1. When the diameter D3 of the polishing body 3 increases to the same size as the inner diameter D1 of the tube W1, the polishing body 3 comes into contact with the inner wall surface W1a of the tube W1. The other end 4b of the string 4 and the other end 5b of the string 5 may be further pulled to press the polishing body 3 and the polishing agent 7 against the inner wall surface W1a of the tube W1. Furthermore, the inner wall surface W1a of the tube W1 can be polished by moving the polishing tool 10 in the tube W1.

(Application example)
Although the example of the pipe W1 shown in FIG. 1 and FIG. 2 extends on a straight line, the pipe W1 may extend on a virtual curve in a three-dimensional space. The virtual curve may have a plurality of bent portions. The pipe W1 is, for example, a cooling circuit or an oil passage. A structure having the pipe W1 extending on a virtual curve in a three-dimensional space can be manufactured using additive manufacturing (AM). When a structure having the pipe W1 extending on a virtual curve in a three-dimensional space is manufactured using additive manufacturing, meltdown may occur and surface roughness may occur on the upper part of the pipe W1. The surface roughness may cause stress concentration and cause a failure. When the surface roughness occurs on the upper part of the pipe W1, the inner wall surface W1a of the pipe W1 may be polished using the polishing tool 10 shown in FIG. 1 and FIG. 2 to smooth the inner wall surface W1a and eliminate the surface roughness.

The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit and scope of the invention. The present invention may also be implemented by combining the above-described embodiment or examples thereof as appropriate.

10 Polishing tool 1 First clamping portion 1a Hole 2 Second clamping portion 2a Hole 3 Polishing body 3a Hole 4, 5 String 4a, 5a One end 4b, 5b Other end 6 Capsule 7 Polishing agent W1 Tube W1a Inner wall surface D1 Inner diameter L1 Length

Claims (1)

A polishing tool for polishing an inner wall surface of a pipe,
A first clamping unit;
A second clamping portion;
a plurality of polishing bodies disposed between the first clamping portion and the second clamping portion and clamped between the first clamping portion and the second clamping portion;
First and second strings that bring the first and second clamping portions closer to each other;
A capsule containing an abrasive;
The capsules are disposed between the plurality of abrasive bodies,
One end of the first string is attached to the second clamping portion,
The first clamping portion is disposed between one end of the first string and the other end of the first string,
One end of the second string is attached to the first clamping portion,
The second clamping portion is disposed between one end of the second string and the other end of the second string,
When the other end of the first string and the other end of the second string are pulled away from the plurality of abrasive bodies, the first and second strings bring the first and second clamping portions closer to each other, and the first and second clamping portions apply compressive stress to the plurality of abrasive bodies. When the plurality of abrasive bodies press against the capsule, the capsule breaks and the abrasive is released outside the capsule.
Polishing tools.

Images