JP3354004B2 - Cutting tool for lightweight steel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting tool used for cutting a lightweight steel material such as an M bar used as a base material for a ceiling.

[0002]

2. Description of the Related Art A hanger is attached to a lower portion of a hanger bolt suspended from a ceiling slab. A hedge supporting member supported by the hanger and a hedge supporting member are disposed so as to intersect with the hedge receiving member. It has been conventionally performed to form a lattice-shaped base frame by connecting the intersections with the edge material by connecting metal fittings, and to attach a ceiling panel to the base frame.

[0003] In the formation of the base frame as described above, a light-weight shaped steel material made of an M bar is commonly used as a field receiving material or a field material.

[0004] The lightweight steel material is very often cut after the framework of the base frame in order to attach a certification device to the ceiling, lay a hollow duct, or form a ceiling inspection opening.

[0005] A method using an electric cutter or a method using a metal cutting saw has been adopted for cutting a lightweight steel material. However, in the cutting method using an electric cutter, there is a danger of fire due to sparks. In addition, there is a risk that chips may be scattered and enter the eyes.

[0006] On the other hand, in the cutting using a metal cutting saw, it takes a very long time to perform the cutting, and it is extremely hard work because the work is performed at a high place.

[0007]

The problem to be solved by the present invention is that M
An object of the present invention is to provide a cutting tool that can cut a light-weight steel material such as a bar very easily and efficiently.

[0008]

In order to solve the above-mentioned problems, according to the present invention, a receiving blade is provided on a front side of a case having a grip at an interval at which a shaped steel material can be inserted,
A flange fitting groove into which the flange of the shaped steel material can be fitted, and a tool fitting groove intersecting the flange fitting groove are formed on a surface of the receiving blade facing the front surface of the case. The blade plate movably provided in the mating groove and the outer peripheral portion of the drive gear rotatably provided in the case and provided with a return rotational force by a spring are connected by a link, and are connected to the grip. The pivot axis of the lever, which can be opened and closed freely and is pushed in the opening direction by a spring
A pinion that engages with the drive gear is rotatably mounted on the top,
The lever is engaged with the pinion by a spring
The pinion when the lever is operated.
Engaged to lock the pinion and release the lever
The engagement with the pinion is released when the lever returns and rotates.
A ratchet pawl is swingably mounted, and the case is engaged with a drive gear to allow rotation of the drive gear in one direction,
A ratchet pawl that prevents rotation in the opposite direction is swingably mounted.

[0009]

In addition , a configuration is adopted in which a long hole centering on the rotation center of the drive gear is formed in the side plate of the case, and an operation pin provided on a side surface of the drive gear is inserted through the long hole.

[0011]

In the cutting tool having the above-mentioned construction, the operation of gripping the lever and releasing the grip is performed by holding the lightweight steel by fitting the flange of the lightweight steel into the flange fitting groove of the blade. By repetition, the drive gear is intermittently rotated in one direction, and the rotation moves the blade plate toward the blade to cut the lightweight steel material with the blade.

In a cutting tool in which an operation pin provided on a side surface of a drive gear is inserted through an arc-shaped long hole formed in a side plate of a case, the operation pin is pressed and moved along the long hole to operate the lever. The drive gear can be rotated in one direction irrespective of this, and the rotation of the drive gear allows the blade plate to be quickly moved to a position where the blade plate comes into contact with the lightweight steel material supported by the blade, thereby reducing the weight. The cutting operation of the shaped steel material can be performed efficiently.

[0013]

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

FIGS. 1 to 5 show a first embodiment of a cutting tool according to the present invention. As shown, the case 1 has a grip 2 at a lower portion. In addition, L on the front side of case 1
A V-shaped arm 3 is provided integrally, and a blade 4 is attached to the inner surface of the arm 3.

Between the blade 4 and the front surface of the case 1, there is formed a profile insertion space 5 which is open at the lower part.
One end of a lid plate 6 that closes the lower opening is rotatably supported via a pin 8 on a support piece 7 provided at the lower front surface of the arm 3.

A hole 9 is formed at the other end of the cover plate 6, while a projection 10 which can be inserted into the hole 9 is provided at the front lower surface of the case 1. A lock claw 11 that can be engaged with the other end of the cover plate 6 is slidably attached to a lower portion of the front surface of the case 1. The plate 6 is held so as to close the lower opening of the section insertion space 5.

The blade 4 has a flange fitting groove 12 in which a pair of flanges a of the light-weight steel material A can be fitted on the inner surface facing the front surface of the case 1, and a blade intersecting the flange fitting groove 12. A fitting groove 13 is formed.

Here, there are several types of lightweight steel members A having different dimensions between a pair of flanges a. Of the several types of lightweight steel members A, two types of lightweight steel members A that are used very often are used. In the embodiment, two sets of a pair of flange fitting grooves 12 are formed on the blade 4 so that A can be held by the blade 4.

It is preferable that the receiving blade 4 is detachably attached to the arm 3 so that it can be replaced according to the type of the lightweight steel material A.

Up and down inside the front part of the case 1;
The blade 4 is provided on the lower surface of the L-shaped arm 3 and the upper surface of the lid plate 6.
Are formed, and upper and lower portions of the blade plate 15 are slidably supported in the guide grooves 14.

The blade plate 15 has a cutting blade 16 at its front part, and the cutting blade 16 has a mountain shape, but the shape of the cutting blade 16 is not limited to this. For example, it may be a linear shape inclined with respect to a straight line orthogonal to the sliding direction of the blade plate 15.

A semicircular drive gear 17 is provided inside the case 1 behind the blade plate 15. The drive gear 17 is rotatably supported around a pin 18 supported on both side plates of the case 1, and teeth 17 a formed on the outer periphery have a saw-tooth shape.

One end of a link 19 is connected to a part of the outer periphery of the drive gear 17, and the other end of the link 19 is connected to a rear end of the blade plate 15. Thus, when the drive gear 17 rotates, the blade plate 15 moves back and forth with respect to the blade 4.

Here, the drive gear 17 and the link 19 are connected by an operating pin 20, which is inserted into an elongated hole 21 formed in the side plate 1 a of the case 1 and which faces the outside of the case 1. The knob 22 is attached to the tip of the.

The elongated hole 21 has an arc shape centered on the pin 18 supporting the drive gear 17. For this reason,
By pressing the knob 22, the drive gear 17 can be rotated. The drive gear 17 is provided with a return rotational force in a direction in which it comes into contact with a stopper 34 provided in the case 1 by a spiral spring 23 supported by a pin 18.

The upper part of a lever 24 provided on the front side of the grip 2 is rotatably supported by the case 1 via a pin 25,
A spring 26 provided between the lever 24 and the grip 2 presses the lever 24 forward.

A semicircular notch 27 is provided above the lever 24.
The circular portion 29 provided at the end of the engaging claw 28 is fitted into the notch 27.

The engaging claw 28 is swingable about the notch 27, and a spring 30 provided on the front side thereof presses the engaging claw 28 backward.

When the lever 24 is swung in the closing direction by grasping the lever 24, the engaging claw 28 engages the drive gear 17 to rotate the drive gear 17 in one direction.
Is disengaged from the driving gear 17 when swinging in the opening direction.

A ratchet pawl 31 is provided on the front side of the lever 24. This ratchet claw 31 is pin 3
2 and is rotatably attached to the case 1 via the housing 2. The ratchet pawl 31 is a spring 33 supported by a pin 32.
Thus, the driving gear 17 is held in a state of being engaged with the driving gear 17, and the engagement allows the driving gear 17 to rotate in one direction and prevents rotation in the opposite direction.

The cutting tool shown in the first embodiment has the above-mentioned structure. To cut, for example, a framed lightweight steel material by using the cutting tool, the locking claw 11 is slid backward to cover the cover plate. 6 is released, and the lid plate 6 is rotated about the pin 8 to open the lower opening of the profile insertion space 5.

Then, from the lower opening, the profile insertion space 5
After the light-weight steel member A is fitted therein and the flange a of the light-weight steel member A is inserted into the flange fitting groove 12, the cover plate 6 is closed.

Next, the knob 22 is pressed to rotate the drive gear 17 in one direction, and the rotation causes the blade plate 15 to move toward the profile insertion space 5 so that the cutting blade 16 is moved to the lightweight steel member A. Abut the parts.

In the above state, when the lever 24 is grasped, the engaging claw 28 is engaged with the drive gear 17 and the lever 2
The drive gear 17 rotates by an amount corresponding to the swing of the fourth gear.

When the grip of the lever 24 is released, the lever 2 is moved toward the grip 2 by the elasticity of the spring 26.
4 swings, and at the time of swinging, the engagement between the engaging claw 28 and the drive gear 17 is released, and the drive gear 17 does not rotate.

For this reason, by repeatedly performing the operation of gripping the lever 24 and the operation of releasing the grip, the drive gear 17 rotates in one direction by a certain angle each time the lever 24 is gripped.

Since the drive gear 17 and the blade plate 15 are connected by the link 19, each time the drive gear 17 rotates, the blade plate 15 moves toward the blade fitting groove 13, and as shown in FIG. Then, the light-weight steel member A is gradually cut, and finally the light-weight steel member A is completely cut.

Since the cutting of the lightweight steel material A is performed by pushing and cutting, a large cutting resistance acts on the receiving blade 4, and the cutting resistance can be received by the cover plate 6. For this reason, even if the arm 3 has a small thickness, the arm 3 is not deformed, and the lightweight steel member A can be cut smoothly.

After cutting the lightweight steel A, the ratchet pawl 31
Is rocked to release the engagement with the drive gear 17, so that the drive gear 17 is returned and rotated by the elastic force of the spring 23.

FIG. 6 shows a cutting tool according to a second embodiment of the present invention. In the second embodiment, instead of the engagement claws 28 in the first embodiment, a pinion 40 that engages with the drive gear 17 is rotatably mounted on a pin 25 serving as a swing center of the lever 24.

A ratchet pawl 41 engageable with the pinion 40 is attached to the lever 24 so as to be swingable. The ratchet pawl 41 is pressed in the direction of engagement with the pinion 40 via the spring 42 and the ball 43, and when the end of the ratchet pawl 41 is pulled up to release the engagement with the pinion 40, the ball 43 is formed on the ratchet 41. The ratchet claw 41 is held in the disengaged state by engaging with the holding surface 44 that has been set.

Since the other structure is the same as that of the first embodiment described above, the same parts are denoted by the same reference numerals and description thereof will be omitted.

In the cutting tool having the above-described configuration, when the lever 24 is gripped, the pinion 40 is prevented from rotating by the engagement of the ratchet pawl 41, so that the drive gear 17 is moved in one direction through the pinion 40. Rotated. Further, when the grip of the lever 24 is released, the lever 24 swings in the opening direction by the elastic force of the spring 26, and the ratchet pawl 41 rotates around the outer periphery of the pinion 40 in a state of disengagement with the pinion 40. Does not rotate.

Therefore, by repeating the operation of gripping the lever 24 and the operation of releasing the grip, the drive gear 17 rotates intermittently in one direction, and the blade plate 15 can be moved toward the blade 4, and its blade can be moved. The light shaped steel material can be cut by the plate 15 and the blade 4.

After cutting the lightweight steel material, the ratchet pawl 31 engaging with the drive gear 17 and the ratchet pawl 41 engaging with the pinion 40 are rocked to release the engagement. Return rotation,
The blade plate 15 can be moved backward.

As described above, the pinion 40 is rotatably provided on the pin 25 serving as the pivot center of the lever 24, and the ratchet pawl 41 which can be disengaged from the pinion 40 is attached to the spring 4.
By pressing the lever 24 in the engagement direction, the drive gear 17 can be rotated by an angle corresponding to the amount of swing of the lever 24, and the amount of movement of the blade plate 15 each time the lever 24 is gripped is shown in FIG. It is larger than that of the embodiment shown, and it is possible to efficiently cut a lightweight steel material.

Further, since a pinion having a small diameter can be used, the operation force of the lever 24 can be reduced.

[0048]

As described above, in the cutting tool according to the present invention, the operation of gripping the lever and the operation of releasing the grip are repeatedly performed to rotate the drive gear in one direction, so that the drive gear is slidable with the drive gear. Since the supported blade plate is connected to the supported blade plate by a link and the blade plate is moved toward the receiving blade, the lightweight steel member held by the receiving blade can be cut very smoothly.

Further, by providing a space between the blade and the blade plate in which the light-weight steel material can be inserted, a cutting tool is set outside the light-weight steel material from the periphery of the framed light-weight steel material. A cutting operation can be performed.

Further, an arc-shaped long hole centered on the rotation center of the drive gear is formed in the side plate of the case, and the operation pin provided on the drive gear is inserted into the long hole, so that the drive gear is pressed by the operation pin. Can be rotated in one direction. Therefore, the blade plate can be quickly moved to the cutting start position where the blade plate comes into contact with the lightweight steel material held by the blade, and the cutting operation can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a front view showing a first embodiment of a cutting tool according to the present invention.

FIG. 2 is a longitudinal sectional front view showing an enlarged part of the above.

FIG. 3 is a sectional view taken along the line III-III in FIG. 2;

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 2;

FIG. 5 is a sectional view showing an operating state of the above.

FIG. 6 is a longitudinal sectional front view showing a second embodiment of the cutting tool according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 case 2 grip 9 blade 12 blade fitting groove 13 blade fitting groove 15 blade 17 drive gear 19 link 23 spring 24 lever 26 spring 31 ratchet pawl 40 pinion 41 ratchet pawl 42 spring

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) B23D 29/00 B23D 15/00 B23D 23/00

Claims (2)

(57) [Claims] 1. A receiving blade is provided on a front side of a case having a grip at an interval at which a shaped steel material can be inserted, and a flange of the shaped steel material can be fitted on a surface of the receiving blade facing a front surface of the case. A mating groove and a blade fitting groove intersecting the flange fitting groove are formed, and a blade plate and a blade plate movably provided from inside the case toward the blade fitting groove are rotatably provided in the case. The link is connected to the outer peripheral portion of the drive gear to which a return rotational force is applied by a spring, and is provided on the grip so as to be openable and closable , and is driven on the swing center axis of the lever pressed in the opening direction by the spring. With gear
The pinion to be engaged is rotatably mounted and attached to the lever
Is pressed by a spring in the direction to engage with the pinion.
The pinion engages with the pinion when the lever is
Stop turning on and return lever released
Ratchet disengaged from pinion during rotation
A light-weight steel material having a ratchet pawl swingably mounted on the case, and a ratchet pawl mounted on the case to engage with the drive gear to allow rotation of the drive gear in one direction and prevent rotation in the opposite direction. Cutting tools. 2. The lightweight as claimed in claim 1, wherein an arc-shaped long hole centered on the rotation center of the drive gear is formed in the side plate of the case, and an operation pin provided on a side surface of the drive gear is inserted through the long hole. Tool for cutting steel.