JP2581077Y2 - Clamp tool - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clamp tool, and more particularly to an improved mechanism for tightening a throw-away tip by simultaneously applying a clamping force from two directions using an L-shaped pin and a holding metal. .

[0002]

2. Description of the Related Art Conventionally, a clamp bit generally fixes a throw-away tip (hereinafter abbreviated as a tip) by a clamping force from one direction by an L-shaped pin.

[0003] However, such a clamp bite has a drawback that the clamp force is limited and cannot be used for heavy cutting. Therefore, there is a mechanism for simultaneously applying a clamp force from two directions to a chip. A clamp tool has been proposed by Japanese Utility Model Publication No. 60-37202 and has been used in some parts.

FIG. 8 is a cross-sectional view showing a clamp mechanism of this type of clamp bite. A fixing bolt 23 is inserted into a cylinder pin hole 22 penetrating an upper surface 21a and a lower surface 21b of the holder 21 at a tip portion of the holder 21. Screwed on,
Due to the tightening force and the downward movement, the head 23a of the fixing bolt 23 presses the stress transmitting portion 25a located at the front end in the counterbore portion 25 of the holding member 24.

[0005] The holding member 24, which has received stress from the head 23a of the fixing bolt 23, has an upper surface of the chip 26 placed in the chip pocket 30 at the lower pressing surface 24a of the beak-shaped tip. Of the cylinder pin 27 located in the cylinder pin hole 22 and by pressing the cylinder pin 27 downward by a projection 24b abutting against a front portion of the upper end annular surface 27a of the cylinder pin 27 to move the cylinder pin 27 downward. Engaging portion 27b recessed in the lower part of
As a result, the horizontal portion 28a of the L-shaped pin 28 swings downward, whereby the head 28b of the L-shaped pin 28 swinging toward the chip pocket side wall surface 30a moves the inner wall surface 26b of the through hole 26a of the chip 26. Chip pocket side wall surface 30
Press in the direction of a. An elastic body 29 such as a spring is accommodated in a lower portion of the cylinder pin hole 22, and a repulsive force caused by contraction during clamping causes upward stress on the horizontal portion 28 a of the L-shaped pin 28 and the cylinder pin 27 during unclamping. Is given.

In such a mechanism, dimensional accuracy of each member is important in order to simultaneously apply a clamping force from two directions to the chip 26, but in order to cope with a case where some deviation occurs. The holding metal 24 is designed to slightly swing about the stress transmitting portion 25a of the holding metal 24 as a fulcrum.

[0007]

However, the above prior art has the following problems.

That is, in the conventional clamp bead, since the tightening force of the fixing bolt is transmitted only to the front portion of the upper end annular surface of the cylinder pin, fine swinging occurs in the cylinder pin, and during the cutting, However, there is a problem that a slight shake occurs on the cut surface due to the swing of the insert.

[0009]

Means for Solving the Problems To solve the above-mentioned problems, the present invention provides a clamp bit in which clamping force from two directions is simultaneously applied to a chip by a holding metal. A cylindrical portion having a lower end annular surface entirely abutting on the upper end annular surface is formed, and a taper is formed on the lower end annular surface so as to be inclined downward with respect to a front direction, and a front side of a counterbore portion for fixing a bolt. A taper was formed on the wall surface at the same angle or at an angle larger than that, which inclined forward to the upper direction.

[0010] Thus, the tightening force of the fixing bolt is transmitted to the entire annular upper end surface of the cylinder, so that the chip does not swing during cutting.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show a clamping mechanism of a clamping tool according to the present embodiment. Reference numeral 1 denotes a holder, and a tip pocket 2 is formed at a tip of the holder. The chip 4 is placed, and the tip 4 is crimped and fixed by the cooperation of the L-shaped pin 5, the cylinder pin 6 and the presser 7.

The L-shaped pin 5 is disposed in a pin pocket 8 having a horizontal portion 5a recessed from the bottom surface of the chip pocket 2, and a head 5b is provided in a fixing hole 4a penetrating in the thickness direction of the chip 4. To position.

The cylinder pin 6 penetrates through the pin pocket 8 and has an upper surface 1a and a lower surface 1 of the holder 1.
b, and is engaged with the horizontal portion 5a of the L-shaped pin 5 by an engagement portion 6a recessed in the lower portion.

On the other hand, a holding metal fitting (hereinafter abbreviated as a metal fitting) 7 is provided with a nut 10 screwed into the cylinder hole 9.
Bolt (hereinafter abbreviated as bolt) 1 to be screwed to
The counterbore part 1 for receiving the head 11a is fixed to the upper surface 1a side of the holder 1 by one head 11a.
2 and a bottom wall surface 12a of the counterbore portion 12, a bolt insertion hole 13 is formed.

The metal fitting 7 has a beak shape at the tip end, and the upper surface of the chip 4 is pressed by a pressing surface 7a below the tip. Further, the lower portion is a cylindrical portion 14,
The inner space 14a has a diameter larger than that of the bolt insertion hole 13, and an elastic body 1 such as a spring is provided around the bolt 11.
5 can be fitted.

Further, as shown in FIGS. 3 and 4, the lower annular surface 14b of the cylindrical portion 14 is a tapered surface inclined downward by about 4 ° with respect to the front direction. In the front part A, the bottom wall surface 12a is a tapered surface inclined downward by about 4 ° with respect to the front direction, and the front wall surface 12b is a tapered surface inclined approximately 4 ° toward the front side with respect to the upward direction. .

In order to clamp the chip 4 from the released state shown in FIG. 5 to the clamp tool thus constructed according to the present invention, the bolt 11 is tightened as shown in FIGS.

That is, by tightening the fixing bolt 11, the head 11a presses the metal fitting 7,
This is moved downward. When the metal fitting 7 moves downward in this way, as shown in FIG. 6, the pressing surface 7a at the tip of the metal fitting 7 presses the upper surface of the chip 4 to directly apply a clamping force, Lower end annular surface 14b
Presses the upper end annular surface 6b of the cylinder pin 6. The stress transmitted to the cylinder pin 6 in this manner is transmitted to the head 5b of the L-shaped pin, and the head 5b causes the inner wall surface 4b of the fixing hole 4a of the chip 4 to face the side wall surface of the chip pocket 2. A clamping force in the direction of 2a is applied. As described above, the clamping force of the two directions is applied to the chip 4 by the tightening of the bolt 11.

However, in this state, the lower end annular surface 14b of the metal fitting 7 and the upper end annular surface 6b of the cylinder pin 6 are in contact only at a part of the front side, and the transmission of stress is unstable. Then, the bolt 11 is further tightened, and as shown in FIG. 7, the metal fitting 7 is swung about the pressing surface 7 a at the tip of the metal fitting 7 as a fulcrum, so that the entire lower end annular surface 14 b of the cylindrical portion 14 is moved to the upper end of the cylinder pin 6. The entire annular surface 6b is brought into contact.

As a result, the transmission of stress is stabilized, and the elastic body 15 fitted around the cylinder pin 6 further contracts by the amount of the swing of the metal fitting 7, and the repulsive force causes
Greater stress can be transmitted to the upper end annular surface 6b of the cylinder pin 6.

That is, a larger clamping force can be applied to the inner wall surface 4b of the fixing hole 4a of the chip 4.

At this time, as described above, at the front portion A of the counterbore portion 12 of the metal fitting 7, the bottom wall surface 12a is a tapered surface inclined about 4 ° downward with respect to the front direction, and the front wall surface 12b is Since the tapered surface is inclined about 4 ° to the front side with respect to the upward direction, the bracket 7 can be swung, and at the front portion A of the counterbore portion 12, almost the entire bottom wall surface 12a and front wall surface 12b are formed. Since the bolt 11 comes into contact with the head 11a, no swing or the like occurs between the bolt 11 and the metal fitting 7, and the clamping force can be applied to the chip 4 stably.

The front wall surface 12b of the counterbore portion 12
Is not necessarily the same as the taper angle of the lower annular surface 14b of the metal fitting 7, but may be larger.

When the taper angle of the lower annular surface 14b is 2 ° to 6 °, the two clamping forces are well balanced, and it is particularly preferable that the taper angle is 2 ° to 4 °.

[0026]

[Effects of the Invention] As described above, the clamp tool of the present invention is a clamp tool in which clamping force from two directions is simultaneously applied to the chip by the holding metal,
A cylindrical portion having a lower end annular surface entirely contacting the upper end annular surface of the cylinder pin is formed at a lower portion of the holding metal, and a taper is formed on the lower end annular surface so as to be inclined downward with respect to the front direction. By forming a taper on the front wall surface of the counterbore portion for fixing the bolt, which is inclined to the front with respect to the upper direction at the same angle or a larger angle, the tightening force of the fixing bolt is transmitted to the entire cylinder upper end annular surface. Even in heavy cutting, the tip does not swing during cutting,
A precise cutting surface without blur can be formed.

[Brief description of the drawings]

FIG. 1 is a top view of a clamp tool according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is a perspective view of a holding member constituting the clamp tool of FIG. 1;

FIG. 4 is a sectional view taken along line YY of FIG. 3;

FIG. 5 is a cross-sectional view showing a released state before clamping in the clamp bite of FIG. 1;

FIG. 6 is a cross-sectional view showing a state in the middle of clamping in the clamp bite of FIG. 1;

FIG. 7 is a cross-sectional view showing a state at the time of completion of clamping in the clamp bite of FIG. 1;

FIG. 8 is a sectional view of a conventional clamp bite.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Holder 1a Upper surface 1b Lower surface 2 Chip pocket 2a Side wall surface 3 Shim 4 Chip 4a Fixing hole 4b Inner wall surface 5 L-shaped pin 5a Horizontal part 5b Head 6 Cylinder pin 6a Engaging part 6b Upper end annular surface 7 (pressing) metal fitting 7a Pressing Surface 12 Counterbore portion 12a Bottom wall surface 12b Front wall surface 13 Bolt insertion hole 14 Cylindrical portion 14a Internal space 14b Lower end annular surface 10 Nut 11 (Fixing) bolt 11a Head 15 Elastic body A Front part

Claims (1)

(57) [Scope of request for utility model registration] An L-shaped pin, a cylinder pin engaged with the L-shaped pin, and a cylinder pin engaged with the L-shaped pin, wherein a throw-away tip having a fixing hole penetrating in the thickness direction is placed in a tip pocket recessed at the tip of the holder. And a clamp bite for pressing and fixing the throw-away tip by cooperation of a holding metal member for pressing the upper surface of the throw-away chip, and a lower annular portion entirely contacting an upper annular surface of the cylinder pin at a lower portion of the holding metal member. A cylindrical portion having a surface is formed, and a taper is formed on the lower annular surface so as to be inclined downward with respect to the front direction. A clamp tool characterized by forming a taper inclined forward to the direction.