JP2505320Y2 - Attachment for pipe cutting - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe cutting attachment for cutting a pipe which is attached to a power tool body having a rotary drive shaft, and more particularly to a pipe having a predetermined pipe thickness from the inside thereof. The present invention relates to a pipe cutting attachment capable of "circular" cutting in a right angle direction.

[0002]

2. Description of the Related Art Conventionally, when installing sewage pipes in toilets, bathrooms, etc. in the construction of buildings, a pipe made of a resin pipe such as vinyl chloride should be used before the floor is constructed. After standing upright above the surface and constructing the floor surface, cut the water distribution pipe from the inside into a "circular slice" at a position slightly lower than the floor surface and connect it to the water distribution pipe of the toilet or bathroom equipment or water distribution trap. Is attached. Therefore, when cutting the water distribution pipe at a position slightly lower than the floor surface, the cutting state must be horizontal, and if the cutting start position and the cutting end position do not match vertically, the upper end of the water distribution pipe will be deformed. Therefore, it causes water leakage.

[0003]

However, in the above case, since there is no ordinary rotating disc cutter or the like which serves as a guide for cutting at a predetermined depth and along the circumference of the inside of the pipe, It was not possible to accurately cut the above resin pipe into a "round slice" at a position lower than the concrete floor surface. Therefore, conventionally, it has been dealt with by manually cutting with a chisel or the like on the cutting line to be cut in a “circular cut” shape on the inner wall surface of the pipe, which is wasteful in terms of efficiency and cost. The improvement was desired. The present invention has been made to solve the above problems, and an object of the present invention is to provide an attachment for cutting a pipe having a predetermined pipe thickness, which can be “circularly cut” from the inside in a direction perpendicular to the pipe axis. And

[0004]

In order to solve the above problems, the pipe cutting attachment according to the present invention is attached to a rotary drive shaft which is rotationally driven by a drive source, and cuts a pipe having a predetermined pipe thickness. A tube cutting attachment for use as a cylinder, which is attached to the rotation drive shaft, has a drive center axis that is the center axis of the rotation drive shaft as a center axis, and has a radius from the drive center axis as a first radius. A tube wall guide portion having a tube wall first guide portion formed by a convex portion and a tube wall second guide portion separated from the tube wall first guide portion, and the drive center axis serving as a rotation axis. And a second radius, which is a distance from the rotary shaft to the outermost peripheral portion of the disc, is larger than the first radius, and is rotatably driven by the rotary drive shaft. Equipped with a blade The drive center axis is parallel to the center axis of the tube, and the rotational drive is performed while the outer peripheral surfaces of the cylindrical convex portions of the tube wall first guide portion and the tube wall second guide portion are in close contact with the inner wall surface of the tube. By moving the shaft along the inner wall surface of the pipe so as to draw a horizontal circumference, the pipe is cut from the inside in a direction perpendicular to the pipe axis.

[0005]

According to the pipe cutting attachment of the present invention having the above-mentioned structure, the outer peripheral cylindrical surface of the cylindrical convex portion of the pipe wall guide portion and the inner wall cylindrical surface of the pipe are arranged such that their central axes are parallel to each other. Since they are in close contact with each other, if the rotation drive shaft is moved along the circumferential direction of the cylindrical surface of the inner wall of the tube while keeping that state, it will move at a predetermined depth and within the circumference of the inside of the tube. Easily "circle" pipes from inside, in the direction perpendicular to the pipe axis, even if there is no guide to cut in the street
Can be cut.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 and FIG. 2 show the structure of a pipe cutting attachment which is an embodiment of the present invention. As shown in Figure 1,
The pipe cutting attachment 1 is an attachment for cutting the resin pipe P having a thickness t, and is screwed onto a rotary shaft 21 which is a rotary drive shaft of a grinder body 20 having a built-in rotary drive source such as a motor (not shown). It is configured to include an attachment main body portion 2 that is attached together, a disc cutter portion 3 that is a blade portion, and a cutter fastening tool 4.

A more detailed structure of the pipe cutting attachment 1 will be described with reference to FIG. 2 (A),
As shown in (B), a shaft connection hole 7 having an internal thread on the inner surface is provided in the upper part of the attachment main body 2, and a male screw provided on the outer peripheral surface of the rotary shaft 21 of the grinder main body 20. Rotating shaft 2
The rotational driving force of 1 is transmitted.

Around the lower portion of the attachment body 2, a tube wall first guide portion 8 and a tube wall having a cylindrical convex shape with a drive center axis X which is the center axis of the rotary shaft 21 as a center axis. The second guide portion 9 is formed. The pipe wall first guide portion 8 and the pipe wall second guide portion 9 are spaced apart from each other, and the first radius, which is the radius from the central axis to the outer peripheral cylindrical surface, is shown in FIG. 2 (B). As shown, both have the same R1. As shown in the figure, the tube wall first guide portion 8 has a relatively large cylindrical surface height (width) as compared with the tube wall second guide portion 9.

At the lower end of the attachment body portion 2, a cylindrical tightening bolt portion 10 having the drive center axis X as a central axis is formed, and a male screw is provided on the outer peripheral surface thereof.

Next, the disc cutter portion 3 which is a blade portion
Is a disk-shaped cutter having the drive center axis X as its center axis, and an insertion hole 14 having a diameter into which the above-mentioned tightening bolt portion 10 can be inserted is provided at the center of the disk body 12. A diamond cutter 13 in which a large number of fine diamond powders are embedded is provided on the outer side of the disk. Then, from the drive center axis X to the disc cutter portion 3
The second radius R2, which is the distance to the outermost periphery of the tube, is the length (R1 +) obtained by adding the thickness t of the pipe to the first radius R1.
It is formed to be slightly larger than t).

The cutter tightening tool 4 is a nut-shaped tightening tool having a tightening nut hole 17 in the center of which a female screw into which the above-mentioned tightening bolt portion 10 can be screwed is provided. When the disc cutter portion 3 is inserted into the insertion hole 14 and screwed / tightened with the tightening bolt portion 10, the disc cutter portion 3 is driven by the rotational driving force of the rotary shaft 21 to drive the central axis X of the drive. Can be attached to the attachment main body 2 so as to be rotationally driven around the rotation axis.

Next, the operation of the electric tool comprising the grinder main body 20 to which the pipe cutting attachment 1 is attached will be described with reference to FIG.

First, in the resin pipe P, the blade 13 of the disc cutter portion 3 is rotated to an arbitrary portion of the cutting line L to be cut into a circular slice shape at a position lower by a predetermined depth D than the surface of the concrete floor surface G. While applying, form a cutting groove for starting the cutter.

Then, the rotational drive of the rotary shaft 21 is stopped and the state shown in FIG. 1 is set. That is, the drive center axis X and the center axis of the resin pipe P are made parallel to each other, and the pipe wall first guide portion 8 and the pipe wall second
A slight pressing force is applied so that both the outer peripheral cylindrical surface of the guide portion 9 and the inner wall cylindrical surface of the resin pipe P come into close contact with each other.

Next, while maintaining the above state, the rotation shaft 21 is started to rotate in the rotation direction shown in FIG. When the rotating shaft 21 is rotated, the disc cutter portion 3
The blade also rotates in the same direction to start cutting the resin pipe P. At the same time, the pipe wall first guide portion 8 and the pipe wall second guide portion 9 provided on the attachment body portion 2 also start to rotate in the same direction, so that the rotary shaft 21 faces from the back to the front in FIG. Such a translational movement will be performed. In this case, an operator who operates this electric tool applies a force in a direction opposite to the translational motion of the rotary shaft 21 to resist the translational motion of the rotary shaft 21 and to move the grinder main body 20 so that the grinder main body 20 is gradually translated. Need to hold. Otherwise, the blade of the disc cutter portion 3 may come off the cutting groove and jump on the inner surface of the resin pipe P. At this time, the outer peripheral cylindrical surfaces of the pipe wall first guide portion 8 and the pipe wall second guide portion 9 rotate while sliding on the inner wall cylindrical surface of the resin pipe P.

After that, while maintaining the above state, the rotary shaft 21, that is, the grinder main body portion 20 is translated along the inner wall cylindrical surface of the resin pipe P so as to draw a circle, so that the resin pipe P is internally moved. Thus, it is possible to cut the resin pipe P in a “circular slice” shape in a direction perpendicular to the central axis. Then, the cutting line becomes the one shown by L in FIG. Finally, the resin pipe P located above the concrete floor G at a predetermined depth D can be cut and removed.

The present invention is not limited to the above embodiment. The above-mentioned embodiment is an exemplification, and a structure having substantially the same configuration as the technical idea described in the scope of claims for utility model registration of the present invention and having the same operational effect is as follows.
Anything is included in the technical scope of the present invention.

For example, in the above-mentioned twist, the pipe wall guide portion is shown as a pipe wall guide portion consisting of two portions, a narrow pipe wall first guide portion 8 and a wide pipe wall second guide portion 9. However, it may be a tube wall guide portion composed of three or more portions. Further, even if it is provided at the position where the pipe wall guide portion is provided, it may be provided not only at the upper portion of the disc cutter portion 3 as in the above embodiment but also at the lower portion of the disc cutter portion 3, that is, at the position of the cutter fastening tool 4. Alternatively, the cutter fastening tool 4 may also be used as the tube wall guide portion.

Further, in the above embodiment, the pipe wall first guide portion 8 and the pipe wall second guide portion 9 which are the pipe wall guide portions are fixed to the attachment main body portion 2 and the rotary shaft 21.
It was configured to rotate together with the rotation of
This is provided with a bearing or the like (not shown) inside, and even if the rotating shaft 21 rotates, the pipe wall first guide portion 8 and the pipe wall second
The guide portion 9 may be configured not to rotate together. According to this structure, the translational force of the rotary shaft 21 as described above is not generated, which is safer in operation. With this configuration, the operator of the electric power tool can cut the pipe at a desired time and at a desired cutting speed.

The material of the tube wall first guide portion 8 and the tube wall second guide portion 9 in the above embodiment is not particularly mentioned, but may be made of metal, or the inner wall surface of the tube may be gripped. It may be formed of a material such as hard rubber so as to facilitate the operation.

Further, in the above-mentioned embodiment, the resin pipe was taken as an example of the pipe to be cut, but it is of course applicable to a metal pipe, a concrete fume pipe or the like. is there.

Further, in the above-mentioned embodiment, an example in which the cutting groove for starting the cutter is formed by the electric tool of the embodiment at the start of cutting the resin pipe P has been described. The first cut groove may be formed with a chisel or the like, and thereafter, the same process as in the above embodiment may be performed.

[0023]

In summary, according to the present invention, there is provided a pipe cutting attachment for cutting a pipe having a predetermined pipe thickness, which is attached to a rotary drive shaft which is rotationally driven by a drive source. A tube wall first guide portion that is attached to a shaft and has a drive center axis that is the center axis of the rotation drive shaft as a center axis and that has a radius from the drive center axis that is a first radius; A tube wall guide portion having a tube wall second guide portion that is separated from the tube wall first guide portion, and a disk shape having the drive center axis as a rotation axis, and the disk from the rotation axis. A second radius, which is a distance to the outermost peripheral portion of the disk, is formed in a disk shape having a diameter larger than the first radius, and is attached so as to be rotationally driven by the rotary drive shaft. Parallel to the central axis of the tube, The rotation drive shaft draws a horizontal circumference along the inner wall surface of the pipe while closely contacting the outer peripheral surfaces of the cylindrical convex portions of the pipe wall first guide portion and the pipe wall second guide portion with the inner wall surface of the pipe. By moving the pipe in such a manner, the pipe is cut from the inside in the direction perpendicular to the pipe axis. Therefore, when cutting the pipe, the pipe wall first guide portion and the pipe wall second guide portion are brought into contact with the inner wall of the pipe, and the pipe is horizontally moved along the inner peripheral surface of the pipe. Can be cut. In particular, the pipe wall guide portion is constituted by the pipe wall first guide portion and the pipe wall second guide portion which is separated from the pipe wall first guide portion, and both guide portions are provided when cutting. Since it moves vertically and contacts the inner wall,
The horizontal state can be reliably maintained during movement during cutting. For this reason, there is no vertical difference between the cutting start position and the cutting end position, and there is no need for troublesome correction work because the upper edge of the cutting edge located below the floor surface is horizontal. In addition, there is no risk of water leakage in the connection with the water distribution pipe, which has a remarkable practical effect in the water distribution pipe connection work.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall configuration when a pipe cutting attachment according to an embodiment of the present invention is used.

2A and 2B are diagrams showing a more detailed structure of the pipe cutting attachment shown in FIG. 1, FIG. 2A being an exploded perspective view and FIG. 2B being an exploded sectional view.

[Explanation of symbols]

 1 Pipe Cutting Attachment 2 Attachment Main Body 3 Disc Cutter Part 4 Cutter Tightening Tool 7 Shaft Connection Hole 8 Pipe Wall First Guide Part 9 Pipe Wall Second Guide Part 10 Tightening Bolt Part 12 Disk Main Body 13 Diamond Cutter Part 14 Insert Hole 17 Tightening nut hole 20 Grinder body 21 Rotating shaft G Concrete floor D Predetermined depth L Cutting line P Resin pipe R1 1st radius R2 2nd radius t Pipe thickness X Drive center axis

Claims (1)

(57) [Scope of utility model registration request] 1. A pipe cutting attachment for cutting a pipe having a predetermined pipe thickness, which is attached to a rotary drive shaft rotated by a drive source, the rotary drive shaft being attached to the rotary drive shaft. To the pipe wall first guide portion and a pipe wall first guide portion having a drive center axis that is the center axis of the cylinder as a center axis and having a radius from the drive center axis as a first radius. A pipe wall guide portion having a pipe wall second guide portion that is spaced apart from the pipe wall, and a disk shape having the drive center axis as a rotation axis, and a distance from the rotation axis to an outermost peripheral portion of the disk. A disc portion having a second radius larger than the first radius, the blade portion being rotatably drivable by the rotation driving shaft, and the driving central axis and the central axis of the pipe being parallel to each other. The pipe wall first guide portion and the pipe wall first (2) While the outer peripheral surface of the cylindrical convex portion of the guide portion is brought into close contact with the inner wall surface of the pipe, the rotary drive shaft is moved so as to draw a horizontal circumference along the inner wall surface of the pipe, thereby causing the pipe to move inside. An attachment for cutting pipes, which is characterized by cutting in the direction perpendicular to the pipe axis.