JPS5823328Y2 - cutting tools - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a cutting tool used to cut, for example, synthetic resin pipes, aluminum materials, etc.

This type of cutting tool rotates the movable blade, which is pivotally supported relative to the fixed blade, in the cutting direction via a notching feed mechanism by rotating the movable handle. It is configured to rotate in the direction.

The return means of the conventional device includes an elastic pulling body such as a spring between the fixed handle integrated with the fixed blade and the movable blade, and as the movable blade rotates in the cutting direction, the tension increases, and the movable blade As soon as the cutting is completed, the elastic pulling body, which is in the maximum tension state, rotates it back, resulting in a sudden rotation, which is dangerous and has a large impact.

In view of these problems with conventional devices, the present invention aims to position the end of the elastic traction body connected to the movable blade in a direction that reduces the elongation of the elastic traction body when the movable blade rotates by a certain angle. It is an object of the present invention to provide a cutting tool in which a connecting end guide portion is formed on a movable blade so as to allow the movable blade to be rotated gently back.

In order to achieve this object, the present invention has a main body having a fixed blade part and a fixed handle part, and a movable blade part that cooperates with the fixed blade part to cut the material to be cut, and which is pivoted on the main body. a supported movable blade; a movable handle pivotally supported on the main body;
a claw portion formed on the movable blade; a notching feed mechanism having a claw that can be engaged with the claw portion and rotates the movable blade in a cutting direction by rotation of a movable handle; a return means for moving the movable blade; a locking claw that engages with the claw arm portion to prevent rotation of the movable blade against the return means;
The cutting tool has a means for releasing the engagement of the locking pawl with the pawl part, and the returning means includes an elastic pulling body connecting the fixed handle part and the movable blade, and a cutting tool formed on the movable blade. The movable blade side connection end of the elastic traction body is connected to the movable blade side connection end of the elastic traction body when the movable blade is rotated by a set angle in the cutting direction. The guide portion is characterized in that one end of the guide portion is moved from a position closer to the connecting end on the fixed handle portion side of the elastic traction body to a position farther from the other end so as to reduce the tension by changing the position of the end. do.

Embodiments of the present invention will be described below with reference to the drawings.

1 to 5, the cutting tool 1 is roughly divided into a main body 4 having a fixed blade part 2 and a fixed handle part 3, a movable blade 7 having a movable blade part 5 and a rook part 6, and a main body 4 having a movable blade part 5 and a rook part 6. A movable handle 9 is pivotally supported on the movable handle 9 via a support shaft 17, a feed pawl 10 is pivotally supported on the movable handle 9 via a pin 19 and can be engaged with the rook part 6, and a movable handle 9 is pivotally supported on the main body 4 and rook part 6
It has a locking pawl 11 that can be engaged with the blade, and a return means 12 provided between the fixed handle portion 3 and the movable blade 7.

The fixed blade part 2 of the main body 4 has a curved shape capable of receiving the cylindrical material to be cut A, and the movable blade 7 pivotally supported by the main body 4 rotates in the cutting direction and cooperates with the fixed blade part 2. Then, the material to be cut A is cut.

The rook part 6, the feed pawl 10, and the locking pawl 11 form a mechanism for feeding the movable blade 7 in increments, and by rotating the movable handle 9 in the cutting direction 15 around the support shaft 17, the feed pawl 10 is It engages with the rook part 6 and feeds it one tooth at a time, rotates in the opposite direction to move the feed pawl 10 to the next tooth of the rook part 6, and in the meantime, the locking pawl 11 engages with the rook part 6. This prevents the movable blade 7 from returning by the return means 12.

The above configuration is substantially the same as that of the conventional device.

The movable handle 9 has a U-shaped cross section and a bifurcated tip, which is pivotally connected to the main body 4 via a support shaft 17.

This support shaft 17 is a cylindrical screw shaft 17 screwed into the main body 4.
The movable handle 9 consists of a central shaft 17C which penetrates through the inside thereof and is prevented from being removed by a retaining ring 17b.
A locking pawl 11 is rotatably provided on the cylindrical screw shaft 17a.

The locking pawl 11 is pressed clockwise in FIG. 1 by a spring 18 and engages with the rook 6.

The locking pawl 11 is formed with a retaining part 20 that protrudes outward from the main body 4, while the movable handle 9 has an operating part 21 formed in the fork-like part thereof, and the movable handle 9 is rotated in the anti-cutting direction. By slightly rotating the operating portion 21, the operating portion 21 can engage with the engaging portion 20. By engaging the operating portion 21, the locking pawl 11 is rotated counterclockwise against the spring 18, and the rook portion 6
cancel the bond with

That is, the retaining portion 20 and the operating portion 21 constitute means for releasing the locking claw 11.

When the movable blade 7 is fed in increments by the feed claw 10, the movable handle 9 is rotated back and forth at a certain angle, but when it is slightly rotated in the counter-cutting direction from the rotation range of the cutting operation, the movable handle 9 rotates with the operating portion 21. It is set to engage with the retaining part 20,
Therefore, the locking pawl 11 is not released during normal cutting operations, and when it is released, the movable handle only needs to be rotated a little further, making the operation extremely simple.

23 is an opening formed in the movable handle 9, through which the feed pawl 10
The rear end of the feed pawl 10 is formed to lock the rear end and is pressed against the rook part 6 by the spring 24 when the movable handle 9 is rotated in the anti-cutting direction within the cutting operation range. The movable handle 9 contacts the movable handle 9 and is configured so as not to rotate beyond a set angle.

The return means 12 has one end attached to the distal end of the fixed handle portion 3 with a pin 2.
A tension spring 27 is connected to the tension spring 27 through the pin 2, and one end is connected to the other end of the spring 27, and the other end is connected to the pin 2.
A connecting body 29 connected to the movable blade 7 via a pin 8, and a long hole 30 (guide portion) for sliding the pin 28 formed in the movable blade 7.
It is composed of.

The connecting body 29 is formed of two thin plates, is bent near the movable blade 7, and is formed so as not to protrude much from inside the fixed handle portion 9.

Incidentally, the elastic traction body formed by the spring 27 and the connecting body 29 may be formed only by the spring.

Rotate the movable handle 9 from the state shown in FIG.
When the movable blade 7 is fed by increments, the pin 28 located at one end 30a of the elongated hole 30 is moved away from the pin 26 by the rotation of the movable blade 7 (see FIG. 2).

When the distance from the pin 26 to the other end 30b of the elongated hole 30 is shorter than the distance from the pin 26 to the one end 30a of the elongated hole 30, the pin 28 is pulled closer to the one end 30a because it is pulled by the spring 27. The elastic traction body moves from the spring 27 to the other end 30b, and the elastic traction body that separates from the spring 27 and the connecting body 29 is reduced from being stretched, and therefore the tension that returns the movable blade 7 is temporarily lowered. Material to be cut A
Even if the locking pawl 11 is released after cutting the movable blade 7, the movable blade 7 returns gently and no sudden return or impact occurs.

That is, the return means 12 slightly prevents the tension of the elastic coupling body from increasing due to the rotation of the movable blade 7 by changing the position of the connecting end of the elastic coupling body with the movable blade 7 using the guide part. The return rotation of the movable blade 7 is made gradual accordingly.

Note that when the movable blade 7 rotates in the opposite cutting direction due to the action of the return means 12, the pin 28 touches the other end 30 during the rotation.
b to one end 30a, making it possible to rotate the movable blade 7 to the final position where it abuts against the stopper 2a.

According to the present invention described in detail above, even if the elastic traction body of the return means for returning the movable blade expands with the rotation of the movable blade and its contractile force increases, the elastic traction body The connecting position of the body on the movable blade side is changed and the tension is weakened, and when the locking claw is released and the movable blade is returned after cutting the material to be cut or during cutting, the returning force by the return means is weakened. , No sudden rotation or impact.

Therefore, the danger and sense of threat caused by the sudden return rotation of the movable blade are eliminated.

[Brief explanation of drawings]

1 to 5 show embodiments of the present invention.
The figure is a left side view, Fig. 2 is a sectional side view of the main part, Fig. 3 is a bottom view, Fig. 4 is a sectional view taken along the line IV-IV in Fig. 1, and Fig. 5 is a perspective view of the main part. . 1...Cutting tool, 2...Fixed blade part, 3
...Fixed handle part, 4 ... Main body, 5
...Movable blade part, 6...Rawl wheel part, 7...
...Movable blade, 9...Movable handle, 10.
...Claw, 11...Latching claw, 12...
...Returning means, 27...Spring, 29...
...Connection body, 30...Long hole.

Claims (1)

[Scope of utility model registration request] a main body having a cutting blade part and a fixed handle part; a movable blade having a movable blade part for cutting a material to be cut in cooperation with the fixed blade part and pivotally supported by the main body; a notching feed mechanism having a pivotably supported movable handle, a pawl portion formed on the movable blade, and a pawl that is engageable with the pawl portion and rotates the movable blade in the cutting direction by rotation of the movable handle;
a return means for rotating the movable blade in a direction opposite to the cutting direction; a locking pawl that engages with a pawl portion to prevent rotation of the movable blade against the return means; and a pawl portion of the locking pawl; a means for disengaging the cutting tool, the return means comprising a resilient traction body connecting the fixed handle portion and the movable blade;
a guide portion formed on the movable blade and connecting the movable blade side connecting end of the elastic traction body so as to be repositionable;
When the movable blade rotates at a set angle in the cutting direction, the position of the connecting end of the elastic traction body on the movable blade side is changed and the tension is reduced. A cutting tool characterized in that the position is changed from a position close to a fixed handle side connecting end to a position far away.