JPS624401Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention consists of a partially arc-shaped main body that is fitted onto the pipe to be cut and fixed concentrically, and a partially arc-shaped main body that is fitted onto the outside of the main body so that it can only rotate freely. A rotating body, a cutting tool integrally attached to the rotating body, and a rotational drive mechanism attached to the main body so as to forcibly drive the rotating body to rotate along the outer periphery of the main body. The present invention relates to a tube cutting device.

The structure of a pipe cutting device generally includes a partially arc-shaped main body that can be fixed concentrically to the outer circumference of the pipe, and a partially arc-shaped rotating body that is fitted onto the main body so that it can only rotate freely. , a cutting tool attached to the rotating body, and a rotation drive mechanism for the rotating body.

Conventionally, the main body for fixing to the pipe and the rotating body are each split into two circular rings, and after these semicircular members are fitted onto the pipe, both are tightened with bolts, nuts, etc. However, in this case, a relatively large work space is required to cover the entire outer circumference of the pipe in order to fit and tighten both semicircular ring members, and in particular, the pipe to be cut is an underground pipe and it is difficult to excavate a pit. If it is necessary to excavate a sufficiently large amount, the work will take a lot of effort, and if the pit is narrow, it will be difficult to tighten the fitting. In addition, there is a slight misalignment in the pitch of the teeth for receiving rotational force at the joint between the two semicircular ring members, resulting in uneven meshing with the drive gear, and friction caused by over-tightening. Chatter (vibration) of the cutting tool due to seizure of moving parts or insufficient tightening
This has the disadvantage that problems such as cutting edges are likely to occur due to the cutting edge.

The purpose of the present invention is to solve such conventional disadvantages, and first, an embodiment thereof will be explained based on the drawings.

The opening L is wider than the outer diameter D of the pipe P to be cut, and the center angle thereof is 180 degrees or more so that the pipe P to be cut can be inserted from the radial direction (upward in the drawing). A fixing device 2, such as a set screw, which can freely fix the main body 1 in a concentric state with respect to the pipe P by protruding movement in the radial direction is provided on the partially arc-shaped main body 1 that is integrated in series over the pipe P. ,
A cutting tool 4 is attached to the rotating body 3 which is externally fitted and held so that only rotation of the main body 1 is possible, and at least one of the cutting tools 4 is always maintained in occlusion or abutment at at least two circumferential locations of the main body 1. Rotary drive bodies 5, 5' are provided (two are provided in the illustrated example) for transmitting rotational force to the rotary body 3 in the state, and these rotation drive bodies 5, 5' are synchronously interlocked with a rotation drive mechanism 6. There is.

A more specific explanation of the structure in the case of the illustrative diagram is as follows.

The partially arc-shaped main body 1 is provided with the fixing tool 2 at a total of eight locations, two locations in the axial direction at locations separated by approximately 40 degrees from the center in the circumferential direction on both left and right sides, and at both left and right ends. When inserting into the pipe P, insert the main body 1 into the pipe P with the lower four fixtures 2 retired and the upper four fixtures 2 protruding by the same amount. Thereafter, the four lower fixing devices 2 are projected to fix the main body 1 concentrically with the pipe P and to prevent it from being pulled out upwards. Main body 1 is rotating body 3
Circumferential groove 1 that rotationally guides the axial direction of the
It has a. This circumferential groove 1a is formed by an arc-shaped protrusion 1b integrally connected to the main body 1, and an arc-shaped retaining plate 1c fixed to the end face of the main body 1 by bolts, welding, etc. in a state opposite to this. .

The rotating body 3 is configured to have a similar shape to the main body 1, and a cutting tool 4 is inserted into a cutting tool stand 3a provided at the center in the circumferential direction so as to be freely sent out in the radial direction. Rotating body 3
The outer periphery of the drive body 3b is geared, and driving bodies 5 and 5', which are gears having the same diameter, mesh with the toothed portion 3b. The drive bodies 5, 5' each have sprockets 7, 7 of the same diameter fixed concentrically to each other, and the sprockets 7, 7 are pivotally supported by support arms 8, 8 extending from the main body 1. . The support arms 8, 8 are located at a distance of approximately 60 degrees to the left and right from the center of the main body 1 in the circumferential direction. A support arm 9 is also provided at the center in the circumferential direction of the main body 1, and a rotating shaft 6a is pivotally supported on this support arm 9.
Sprockets 6 having the same diameter are attached to this rotating shaft 6a.
b, 6b are fixed, and the rotational drive mechanism 6
It consists of and the sprocket 6b,
Chains 10, 10 are wound between the sprockets 6b and the sprockets 7, 7, respectively.

When a rotation operation handle is set on the rotation shaft 6a and the rotation shaft 6a is driven and rotated manually or forcibly by interlocking with an electric motor, etc., the rotation of the drive bodies 5 and 5' in the same direction and at the same speed causes The rotating body 3 is rotated. As this rotation occurs, the rear end 3'' of the rotary body 3 disengages from one drive body 5 (the right side when the direction of rotation is arrow A), but remains in engagement with the left drive body 5'. This state Eventually, the front end 3' of the rotating body 3 comes to fit onto the right end 1'' of the main body 1, and then comes to re-engage with the right drive body 5. Immediately after that, the rear end 3'' of the rotating body 3 is disengaged from the left drive body 5' and eventually separated from the left side 1' of the main body 1. Despite having an opening L on both sides of the body 3, it rotates continuously in one direction while maintaining a stable concentric state, and the pipe P is
Cutting.

Next, to describe an application example, the driving bodies 5, 5'
The transmission means from the rotating body 3 to the rotating body 3 may be a high friction transmission other than tooth engagement, and the number of driving bodies 5, 5' may be three or more. Furthermore, the cutting tool 4 has a structure in which it is automatically fed every rotation of the rotating body 3;
Since this is well known, illustration and explanation will be omitted.

In summary, the pipe cutting device according to the present invention allows each of the main body 1 and the rotating body 3 to be cut into a pipe P to be cut.
The opening L is wider than the outer diameter D of the pipe P to be cut so that insertion fitting from the radial direction is possible.
and is formed into a partial arc shape with a central angle of 180 degrees or more so as to have a circumferential length exceeding half the circumference of the pipe P to be cut, and the rotational drive mechanism 6
is equipped with rotary drive bodies 5, 5' that engage and drive the rotary body 3 at at least two positions spaced apart from each other by a width larger than the opening L width of the rotary body 3 in the circumferential direction of the main body 1, so that a plurality of rotations can be achieved. The present invention is characterized in that either one of the driving bodies 5, 5' is configured to always transmit rotational power to the rotating body 3.

That is, simply inserting the entire device into the pipe P to be cut from the radial direction and fixing it to the pipe P with the fixtures 2... eliminates the need for connecting and assembling the rotating body 3. The amount of excavation required to form a pit is small, and the overall work efficiency including excavation work can be improved, especially when dealing with underground pipes. As mentioned above, it is possible to perform the fixing work to P easily and quickly, and it has a remarkable effect in terms of construction. body 3
A plurality of rotational driving bodies 5, 5' are provided so that at least one of them is always engaged with or in contact with the rotating body 3, and this is kept in a concentric state with the main body 1, that is, the pipe P. It is possible to continuously rotate in one direction while being maintained in a good condition, and while it is possible to improve the work efficiency mentioned above, it is also possible to cut the pipe P with high precision and smoothly (including cutting, of course). I was able to do it.

[Brief explanation of the drawing]

The drawings show an embodiment of the pipe cutting device according to the present invention, and FIGS. 1 and 2 are front views showing the operation, FIG. 3 is a plan view, and FIG. 4 is a partially enlarged sectional view. 1...Main body, 1a...Peripheral groove, 2...Fixing tool, 3
...Rotating body, 4...Cutting tool, 5,5'...
Rotation drive body, P...pipe, 10...chain, 6...
...Rotary drive mechanism.

Claims (1)

[Claims for Utility Model Registration] A partially arc-shaped main body 1 that is externally fitted onto the pipe P to be cut and fixed concentrically, and a partially arc-shaped main body 1 that is externally fitted and held with respect to the main body 1 so that it can only rotate freely. a rotating body 3, a cutting tool 4 integrally attached to the rotating body 3, and a cutting tool 4 that connects the rotating body 3 to the main body 1.
In the pipe cutting device, each of the main body 1 and the rotating body 3 is attached to the pipe P to be cut, and includes a rotary drive mechanism 6 attached to the main body 1 so as to be forcibly driven to rotate along the outer circumference of the pipe P. It has an opening L wider than the outer diameter D of the pipe P to be cut, and has a circumferential length exceeding half the circumference of the pipe P to be cut, so that insertion fitting from the radial direction is possible. The rotary drive mechanism 6 is formed into a partial arc shape with a central angle of 180 degrees or more, and the rotary drive mechanism 6 has a rotary body at at least two positions spaced apart from each other by a width larger than the opening L width of the rotary body 3 in the circumferential direction of the main body 1. a rotary drive body 5 that engages with and drives the rotation drive body 3;
5', and one of the plurality of rotary drive bodies 5, 5' is configured to always transmit rotational power to the rotary body 3. The rotary drive bodies 5, 5' are chains 10, 1
The pipe cutting device according to claim 1, which is rotatably driven by a rotary drive mechanism 6 via a rotary drive mechanism 6. The pipe cutting device according to claim 1 or 2, wherein the main body 1 has a circumferential groove 1a that rotationally guides the rotating body 3 while restricting it in the axial direction.