JPH06246532A - Cutting tool - Google Patents

Abstract

PURPOSE:To provide a cutting tool compact and lightweight with excellent work performance by passing material to be cut through the through hole of a bracket connected to the joint of a body by a hinge, and making a fixed cutting edge and a movable cutting edge bite each other inside the bracket to cut the material to be cut. CONSTITUTION:A joint 3 is connected to a body with a built-in drive source, and a bracket 4 provided with a through-hole 46 is connected to the joint 3 by a hinge pin 44. A fixed cutting edge 5 is fixed to the inside of the bracket 4 in such a way as to face the through-hole 46, and a ram 6 is disposed inside the bracket 4 in such a way as to be reciprocated vertically to the centerline of the through-hole 46. A movable cutting edge 7 is disposed inside the bracket 4 in such a way as to be reciprocated in association with the reciprocating motion of the ram 6 and brought into contact with the fixed cutting edge 5 at the reciprocating time. An oil passage 8 reaching the rear end of the ram 6 from the drive source through the joint 3 and hinge pin 44 is further formed. A long bolt B to be cut is length adjustment is then passed through the through- hole 46 and cut by the fixed cutting edge 5 and the movable cutting edge 7.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to cutting tools.
This cutting tool is suitably used for cutting a Zungiri bolt protruding from a ceiling or a wall in a building to remove an excessively long portion thereof. Further, it is also suitably used for cutting a Zungiri bolt that is not yet fixed to a building to a predetermined length on the ground.

[0002]

2. Description of the Related Art In a building such as a building, a long all-screw bolt called a Zungiri bolt is embedded in a ceiling or a wall in order to install an air conditioning duct or a fluorescent lamp. That is, in the air-conditioning duct, the four corners are framed by angles, and Zungiri bolts are passed through the angles and tightened with nuts to fix them in place. In addition, in a fluorescent lamp, a Zungiri bolt is passed through a screw hole provided in the umbrella, and the nut is tightened and fixed.

The Zungiri bolt used in this way is
In order to be able to accommodate different sizes of installation equipment, it is embedded with a machined length. Therefore, an extra length is projected after the device is installed, and if left unattended, it not only spoils the appearance of the building, but is also extremely dangerous.

Therefore, the excessively protruding Zungiri bolt is cut at the installation site. Conventionally, as a cutting tool for that purpose, a cutting blade holder having a pair of cutting blades composed of a fixed blade and a movable blade is directly connected and fixed to a body containing a drive source such as an electric hydraulic plunger and an operating ram. Things were being used. A handle, which also serves as an oil tank and an electric motor storage portion, is provided on the body at a substantially right angle to the longitudinal direction of the body.

At the time of work, the Zungiri bolt is inserted between the fixed blade and the movable blade, the handle is held to support the cutting tool, and the movable blade is moved toward the fixed blade by the hydraulic pressure transmitted from the operating ram. By doing so, shear stress was applied to the Zungiri bolt to cut it.

[0006]

However, the above-mentioned conventional cutting tool has the following problems. First, since the cutting blade holder is directly connected and fixed to the body, the angle formed by the body and the Zungiri bolt is always substantially a right angle. Therefore, when cutting the Zhangiri bolt protruding downward from the ceiling, the arm of the cutting tool that supports the gravity of the cutting tool is substantially horizontal. As a result, the same person cutting many Zungiri bolts in succession is
It will be very hard work.

Second, since the cutting blade holder is directly connected and fixed to the body, it is impossible to make the bolt length after cutting shorter than the radius of the body. However, if the distance between the cutting blade holder and the body is increased, the loss of hydraulic pressure transmitted from the operating ram to the cutting blade increases. As a result, the electric motor for supplying the hydraulic pressure required for cutting, the plunger, and the operating ram are all large in size, and it becomes more difficult to support them with one arm. An object of the present invention is to solve the above problems and to provide a small and lightweight cutting tool having excellent workability.

[0008]

The means are a drive source for fluid pressure, a body containing the drive source, a joint connected to the body so as to be rotatable about an axis, and a hinge for the joint. Brackets connected to each other with through holes, fixed blades fixed to the inside of the brackets toward the through holes, and built into the bracket in a state capable of reciprocating in a direction perpendicular to the center line of the through holes. And a movable blade built into the bracket so as to reciprocate with the reciprocating movement of the ram and contact the fixed blade when moving forward,
A cutting tool is provided with a fluid path from a drive source to a rear end of a ram via a joint and a hinge.

Here, the fluid is a pressure medium, usually oil, but is not limited to this and may be gas. What is a drive source?
For example, in the case of hydraulic pressure, it is a hydraulic mechanism including a hydraulic cylinder and a plunger, and has a transmission mechanism that converts the output or human power from the electric motor and transmits it to the plunger. The through hole is for holding the Zungiri bolt.

A desirable feature of this cutting tool is that the through hole formed in the bracket has a one-sided opening that is open to one side in a cross section in the direction perpendicular to the center line.

[0011]

The operation of cutting the Zungiri bolt using the cutting tool of the present invention is as follows. First, the joint is rotated with respect to the body so that the positional relationship between the cutting tool and the Zungiri bolt when the Zungiri bolt is inserted into the through hole is suitable for the working environment. And / or rotate the bracket about the hinge.

Next, after fixing the joint and the bracket, the Zungiri bolt is inserted into the through hole and applied to the fixed blade. When the drive source is operated, the fluid pressure generated from the drive source is transmitted to the ram by using the fluid in the fluid passage as a medium. Then, as the ram moves, the movable blade moves and collides with the Zungiri bolt. As a result, shear stress is applied to the Zungiri bolt, and the Zungiri bolt is cut. The movable blade moves as it is, meshes with the fixed blade, and stops.

[0013]

Embodiments of the cutting tool of the present invention will be described with reference to the drawings. FIG. 1 is a fragmentary front view showing a cutting tool of the present invention. FIG. 2 is an enlarged cross-sectional view of the main part of FIG.
FIG. 3 is a cross-sectional view of the portion of FIG. 2 taken along the axis of the joint as seen from the handle side. FIG. 4 is a perspective view showing the ram, the movable blade, and the cutter block extracted.

[Structure of Embodiment] A cutting tool 1 includes a drive source (not shown) for fluid pressure, a body 2 containing the drive source,
It is provided with a female joint 3, a bracket 4, a fixed blade 5, a ram 6 built in the bracket 4, and a movable blade 7.

A small handle 21 and a large handle 22 are attached to the body 2 so as to form an angle with respect to the axis thereof. An oil tank (not shown) is built in the small handle 21, and a battery (not shown) is built in the large handle 22. At the center of the body, there is a built-in electric motor connected to the battery and a cylinder connected to the oil tank and containing a plunger. In this example, this electric motor and the plunger are drive sources.

An internal gear is fixed to the body 2 around the output shaft of the electric motor. A pinion gear meshes with the internal gear and the output shaft to form a planetary gear device. The rotation shaft of the pinion gear is fixed to a motor that is concentric with the output shaft of the electric motor. Further, a crankshaft is eccentrically fixed to the tip of the motor with respect to the rotation shaft of the motor. The outer peripheral surface of the crankshaft is in contact with the contact surface of the plunger. Further, a male joint 23 protruding stepwise is attached to the tip of the body 2.

The female joint 3 comprises a cup portion 31 and a rectangular parallelepiped portion 32. The cup portion 31 is fitted to the male joint 23. On the inner peripheral surface of the cup portion 31 and the outer peripheral surface of the male joint 23, the split grooves 2 facing each other are formed.
4, 33 are provided in the circumferential direction. A piano wire 34 is inserted into an annular space formed by the split groove 24 and the split groove 33. In this way, the female joint 3 is connected to the male joint 23 so as to be rotatable about its axis. Moreover, a disc spring 25 is provided between the male joint 23 and the female joint 3.
And the elastic force regulates the rotational force of the female joint 3.

On the other hand, the rectangular parallelepiped portion 32 of the female joint 3 is provided with a hinge hole 32a in a direction perpendicular to the axis of the cup portion 31. An oil reservoir 32b having a large diameter is provided in the center of the hinge hole 32a. Bracket 4
Is composed of a hinge block 41 connected to the female joint 3 by a hinge pin 44, and a cutter body 42 and a cutter block 43 integrated with the hinge block 41.

The hinge block 41 includes a female joint 3
A hinge hole 41a that is concentric with the hinge hole 32a provided in the rectangular parallelepiped portion 32 is provided. This hinge hole 41a
Also, an oil reservoir 41b having a large diameter is provided in the center. Then, by inserting the hinge pins 44 into these hinge holes, the bracket 4 is fixed to the female joint 3 in a state in which the bracket 4 can be turned by 90 °.

The hinge pin 44 has an oil reservoir 32b and an oil reservoir 4b.
A communication hole 44a that communicates with 1b is provided in the radial direction and the axial direction. A wave washer 44b is fitted to the hinge pin 44 at the contact position between the rectangular parallelepiped portion 32 of the female joint 3 and the hinge block 41, and the elastic force of the wave washer 44b regulates the rotational force of the bracket 4.

The main body of the cutter body 42 is manufactured integrally with the hinge block 41, and the inside thereof is divided into a cylinder portion 49 on the hinge block 41 side and a holder portion 45 on the tip side. The holder portion 45 is provided with a through hole 46 in the extending direction of the hinge block 41. The through hole 46 has a one-sided shape having an opening 46a on the side in a vertical cross section with respect to the center line. Further, guides 42a, 42b, 42c are fastened to the holder portion 45 with bolts. The cylinder portion 49 is oil-tightly held by the cylinder end 47 and the annular seal ring 48. The cutter block 43 is sandwiched between the cutter body 42, the main body of the cutter body 42, and the guides 42a, 42b, and 42c, and connects a ram described below and a movable blade.

The fixed blade 5 has a thick C-shaped cross section, and is fixed to the holder portion 45 of the cutter body 42 so that the blade surface faces the through hole 46. The inner peripheral surface of the fixed blade 5 is a full screw having the same pitch as the Zungiri bolt to be cut.

The ram 6 is built in the cylinder portion 44 of the cutter body 42 so as to be capable of reciprocating. Ram 6
Has a substantially cylindrical shape, but the tip portion is flatly divided. Therefore, the tip portion of the ram 6 has a flat surface 61 in its axial direction. Cylinder part 4 on the outer periphery of ram 6
A returning spring 62 is arranged in a spiral shape in a gap between the turning spring 62 and the spring 4. An annular seal ring 6 is provided at the rear end of the ram 6.
3 is fitted and holds the cylinder portion 44 in an oiltight manner. The cutter block 43 has a flat surface 6 at the tip of the ram 6.
It is fixed to 1 with a bolt 64.

The movable blade 7 has the same shape as the fixed blade 5, and is fixed to the cutter block 43 by a bolt 71 so that the blade surface faces the fixed blade 5 and faces the through hole 46. An oil passage 8 is provided between the plunger built in the body 2 and the male joint, the female joint 3, and the hinge pin 44 to reach the rear end surface of the ram 6. The inside of the oil passage 8 is filled with oil. Oil sump 32
The b and 41a and the communication hole 44a form a part of the oil passage 8. Although not shown, the hinge pin 44 has an oil reservoir 3
Annular seal rings are fitted at positions on both sides of 2b and 41b, respectively, to keep the oil passage 8 oil-tight.

[Effects of the Embodiment] The operation of cutting the Zungiri bolt using this cutting tool 1 is as follows.

First, the female joint is rotated with respect to the body or the direction of the bracket is changed so that the positional relationship between the cutting tool and the Zungiri bolt when the Zungiri bolt is inserted into the through hole is suitable for the working environment. For example, when cutting a Zungiri bolt that protrudes into a place where workers cannot enter, when cutting a Zungiri bolt that horizontally protrudes from the wall, or when cutting a Zungiri bolt that is not yet buried in the building on the ground, The direction of the bracket may be the same as in FIG.

After the female joint and the bracket have been fixed, the Zungiri bolt B is inserted into the through hole as shown in FIG. At this time, if the Zungiri bolt B is too long, the Zungiri bolt may be fitted through the opening 46a. When the electric motor is turned on, the rotation output of the electric motor is transmitted to the pinion gear that rotates in synchronization with the output shaft. Then, the rotor rotates together with the pinion gear and transmits the rotational power to the crankshaft. Then, the rotary motion of the crankshaft is converted into the reciprocating motion of the plunger, and the hydraulic pressure inside the oil passage 8 is increased.

The increased hydraulic pressure is transferred to the ram 6 via the oil passage 8.
Is transmitted to the rear end face. Then, the ram 6 becomes the through hole 46.
While moving toward, the movable blade 7 moves and collides with the Zungiri bolt B. As a result, Zungiribolt B
Shearing stress is applied to and the Zungiri bolt B is cut. The movable blade 7 moves as it is, meshes with the fixed blade 5, and stops.

When cutting the Zhangiri bolt B protruding downward from the high ceiling, the female joint 3 is manually rotated by 180 ° clockwise as viewed from the left side of FIG. 2 or 3. Further, the hinge block 41 is rotated clockwise by 90 °, and human power is released at that position to fix the female joint 3 and the bracket 4. Then, as shown in FIG. 6, the Zungiri bolt B is inserted into the through hole 46 and applied to the fixed blade 5. After that, the cutting work is performed as in the case of FIG. During this work, the line connecting the center of gravity of the cutting tool 1 and the shoulder of the worker is
It matches the direction of gravity. Therefore, the gravitational force of the cutting tool 1 is supported by the shoulder of the operator, and the arm is not overloaded.

As described above, in the cutting tool 1 of this embodiment, the orientation of the bracket 4 with respect to the body 2 can be changed in either the X direction or the Y direction. Therefore, the operator can perform the cutting work in the most comfortable posture, and can cut the body shorter than the thickness of the body.

Further, since the ram 6 is built in the bracket 4, there is almost no loss of hydraulic pressure transmitted from the ram 6 to the movable blade 7. As a result, the load applied to the electric motor is small, and not only the built-in ram 6 but also the electric motor and the plunger serving as a drive source may be small. Therefore, the entire cutting tool 1 is light in weight, and the burden on the operator is small. Furthermore, since the bracket 4 is provided with the opening 46a, the cutting blade can be easily grasped by the cutting blade even if the Zungiri bolt B is a considerably long one.

[0032]

As described above, the present invention provides a cutting tool which is excellent in workability and has a small size and a light weight because it has the above structure. Therefore, it can be used in various work environments.

[Brief description of drawings]

FIG. 1 is a fragmentary front view showing a cutting tool according to an embodiment.

FIG. 2 is an enlarged sectional view of a main part of FIG.

FIG. 3 is a cross-sectional view of a main part of the cutting tool taken along the axis of the joint as seen from the handle side.

FIG. 4 is a perspective view showing a ram, a movable blade, and a cutter block according to the embodiment.

FIG. 5 is a view showing a usage state of the cutting tool of the embodiment.

FIG. 6 is a view showing another usage state of the cutting tool of the embodiment.

[Explanation of symbols]

1 ・ ・ Cutting tool 2 ・ ・ Body 3 ・ ・ Female joint 4 ・ ・ Bracket 5 ・ ・ Fixed blade 6 ・ ・ Ram 7 ・ ・ Movable blade 44
..Hinge pins S..Ceiling B..Zungiri bolts

Claims (2)

[Claims] 1. A drive source for fluid pressure, a body containing the drive source, a joint connected to the body so as to be rotatable about an axis, and a through hole connected to the joint by a hinge. Bracket, the fixed blade fixed inside the bracket toward the through hole, the ram built into the bracket so that it can reciprocate in the direction perpendicular to the center line of the through hole, and the reciprocating motion of the ram. And a movable blade built into the bracket so as to come into contact with the fixed blade when moving forward, and a fluid path from the drive source to the rear end of the ram via the joint and hinge is provided. A cutting tool characterized by being 2. The cutting tool according to claim 1, wherein the through hole provided in the bracket has a one-sided opening that is open to one side in a cross section in a direction perpendicular to the center line.