JPS6144737Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hand-held simple pipe cutter, particularly a pipe cutter having a plurality of blades suitable for easily cutting buried gas pipes and water pipes at construction sites.

When cutting buried gas pipes or water pipes in a work space such as a construction site where these pipes are buried, it is generally not possible to rotate the pipes, so it is necessary to rotate the cutter around the pipes. However, especially when working space is limited, it is not possible to rotate the cutter around the pipe once. Or it becomes very difficult to do. Therefore, in such cases, a cutter having a plurality of roller blades positioned around the circumference of the tube is used, and the tube can be cut by rotating and reciprocating the cutter within a predetermined angular range. In this type of cutter, each roller blade is responsible for cutting around the tube within a predetermined angular range, so it is essential that these roller blades are always located in the same plane. Otherwise, the cutting lines will not overlap and a clean right-angled cut surface will not be obtained.

However, if the roller blades are all located within one plane that includes the cutting line of the pipe, the pipe to be cut is actually held in line contact with the plurality of roller blades. Therefore, the pipe or cut is likely to wobble in the axial direction. Therefore, in such a case, some kind of holding means is required to hold the pipe on the cutter body.

In particular, by developing a new and simple structure as a holding means, the present invention has a structure that is suitable for cutting pipes in a pinch work space such as a construction site where gas pipes or water pipes are buried. It is an object of the present invention to provide a pipe cutter that is simple and easy to operate and handle.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

The pipe cutter according to the present invention has, for example, a substantially U-shaped main body 1, and at least one, preferably two roller blades 3A are attached to the main body 1.
These roller blades 3A are rotatably supported by shaft pins 5A in a cutting plane perpendicular to the pipe P to be cut. The shaft pin 5A is preferably the roller 7
A, and these rollers 7A prevent the roller blades 3A from biting into the pipe P by the wall thickness and cutting is completed, when the outer periphery of the pipe P comes into contact with the rollers 7A and the roller blades are no longer sent in the radial direction. Acts as a stopper to prevent

A slider 11 is attached to the main body 1 and is capable of reciprocating within the cutting plane. The slider 11 is the main body 1
It is slidably attached to a guide rail or dovetail groove 13 formed in the. The slider 11 also has at least one, preferably two roller blades 3B on the roller 7.
It is rotatably supported via a B-attached shaft pin 5B. All four roller blades 3A, 3B are located within the same cutting plane.

A screw rod 17 that is slidably fitted into the hole 2 of the main body 1 is rotatably attached to the slider 11. The female threaded portion 23 of the swing lever 21, which is rotatably supported on the main body 1 by a pin 25, faces the hole 2 so as to be freely protrusive and retractable, and in the illustrated position, the female threaded portion 23 is screwed into the threaded rod 17. ing. As a result, by holding the knob 19 of the screw rod 17 and rotating the screw rod 17 in a predetermined direction, the slider 11 is moved back and forth in the axial direction of the screw rod 17. In this way, the four roller blades 3A and 3B can be pressed onto the same circumference on the outer circumference of the pipe P. Therefore, by holding the knob 19 and rotating the entire cutter back and forth in the clockwise direction in FIG. P can be cut. Note that until the cutting of the pipe P is completed, the slider 11 must be advanced in the radial direction an appropriate number of times by rotating the threaded rod 17 with the knob 19 to increase the cutting depth of the roller blade 3B.

The lever 21 is always biased counterclockwise in FIG. 1 by a spring 29 provided between it and the main body 1.
The threaded engagement between the threaded rod 17 and the threaded portion 23 is ensured. Therefore, when the free end of the lever 21 is pressed against the spring 29 in the direction of arrow
Leave from 7. As a result, the screw rod 17 becomes free, so that the slider 11 can be quickly returned after the cutting operation is completed. In order to perform this quick return of the slider 11, the other end 14A of a spring 14 connected to the pin 16 of the main body 1 is connected to the slider 11.
As soon as the slider 11 is freed from the slider 11, the slider 11 is pulled back to the left in FIG.

However, since the cutter described above has roller blades at several places on the outer circumference of the pipe P, it is not necessary to rotate the entire cutter around the pipe once when cutting the pipe P.
By rotating the roller blade 3 around the axis of 7.
Simply rotate the entire cutter back and forth or left and right around the pipe within a certain angle range while feeding B little by little (if there is only one roller blade, it is necessary to rotate the entire cutter several times around the pipe). However, since the pipe P is only held in line contact with the roller blades 3A and 3B, the pipe P or the cutter tends to wobble in the axial direction. Therefore, according to the present invention, the slider 11 has an upper arm 3 that forms a V-shape.
1 and a lower arm 33 are provided. These upper arm 31 and lower arm 33 are the slider 1
They are rotatably supported by a shaft 35 provided in the main body 1 and can be opened and closed mutually. Arms 31 and 33 are each width
W ₁ and W ₂ (FIG. 3), so that the outer periphery of the pipe P can be held over a certain length. That is, the upper arm 31 and the lower arm 33 both extend a certain width on both sides of the cutting plane including the roller blades 3A and 3B when viewed in the pipe axial direction, and cut the pipe P by the roller blades 3A and 3B.
Grip firmly on both sides of 3B.

Torsion springs 40 and 41 are provided between the upper arm 31 and the lower arm 33 on both sides of the slider 11, and bias these arms in the closing direction. Furthermore, notches 45 are provided at the proximal ends of the upper arm 31 and the lower arm 33, respectively.
46 are provided, and these notches contact pins 49 fixed to the slider 11, thereby restricting the closed position of both arms. That is, the arms 31, 33 can be rotated in the closing direction until the respective notches 45, 46 contact the pin 49, whereas there is no such restriction in the opening direction. Both arms 31 and 33 are roller blades 3A and 3
As the cutting into the pipe P by B progresses, the pipe P is gradually expanded against the springs 40 and 41 while holding the pipe P between them. In addition, the arms 31 and 33 have a second
As shown in the figure, a cutout 34 (only the cutout 34 of the arm 33 is shown; a similar cutout is formed at a corresponding position on the arm 31) is provided to prevent the roller blade 3B from interfering with the roller blade 3B. Note that the strength of the springs 40 and 41 is preferably set so that the pipe P can be held with a certain amount of force even in the maximum closed position.

As described above, according to the present invention, the pipe P is firmly held by the holding means, so the pipe P and the cutter do not wobble, and the plurality of roller blades can cleanly cut the pipe P at a predetermined cut surface. Can be cut vertically.

It will be understood that, instead of being provided on the slider, the holding means may be provided on the opposite side of the main body 1 (for example, in the middle of the roller blades 3A, 3B) and will have exactly the same effect.

[Brief explanation of the drawing]

Figure 1 is a front view of the pipe cutter according to the present invention;
2 is a bottom view of FIG. 1, FIG. 3 is a right side view of FIG. 1, and FIG. 4 is a sectional view taken along the line -- of FIG. 1...Main body, 3A, 3B...Roller blade, 11...
...Slider, 17...Screw rod, 31, 33...
Arm, 40, 41...spring.

Claims (1)

[Scope of utility model registration request] a main body having at least one roller blade rotatable in a plane perpendicular to the axis of the pipe to be cut; and at least one roller blade opposed to the roller blade in the plane; a slider movably attached to the main body in order to move the blade toward and away from the roller blade of the main body within the above-mentioned plane; and a slider having a width that spans both sides of the roller blade of the slider when viewed in the axial direction of the pipe to be cut, and the pipe to be cut. and holding means for holding the slider from the radial direction, and the holding means is formed by openable and closable V-shaped arms that are pivotally supported on the slider or the main body, and these V-shaped arms are normally biased by a spring in the closing direction. A simple pipe cutter with multiple blades.