JP2000246515A - Clamping mechanism for throw-away tip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply and quickly replace a throw-away tip to be mounted to a boring bite or the like. SOLUTION: A supporting seat 9 having a seat bottom and two seat walls, is provided for a holder 8, and an oblique surface 5 extended to the back surface 2e of a tip is provided for the upper surface of a throw-away tip 1 to be mounted to the supporting seat 9. In addition, a clamping screw 11 is provided for a position holding the tip interspaced with the seat wall 9b of the supporting seat 9 so as to let the tapered head part of the clamping screw press the oblique surface 5 at the upper surface of the tip. This constitution thereby enables the tip to be mounted to/demounted from the supporting seat 9 only by somewhat loosening the clamping screw.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clamp mechanism for a throw-away tip suitable for a boring tool or the like.

[0002]

2. Description of the Related Art A support seat having a seat bottom and two seat walls is provided at the tip of a holder, and a polygonal throw-away tip is mounted on the support seat. As a clamp mechanism of a method of fixing the holder to the holder by pressing with a tapered head of a clamp screw, for example, there is a mechanism disclosed in Japanese Patent Application Laid-Open No. 9-236110. It is necessary to temporarily remove the clamp screw from the holder, and the replacement time is prolonged and there is a concern that the clamp screw may be lost. Japanese Patent Application Hei 10-232
No. 993.

The clamp mechanism restrains one side of the vertically used chip at the bottom of the support seat, further restrains the bottom and back of the chip by the two seat walls, and fixes the clamp screw to the bottom of the chip. The taper head of the clamp screw presses the slope of the concave portion formed on the upper surface of the chip by providing the chip at a position where the chip is sandwiched between the chip and the seat wall.

[0004]

In the clamp mechanism proposed by the present applicant, as shown in FIG. 9A, the tapered head of the clamp screw 11 is inserted into the concave portion 12 on the upper surface of the throw-away tip 1. For this reason, as shown in FIG. 9B, unless the clamp screw 11 is loosened until the tapered head of the screw completely comes out of the concave portion 12, interference with the clamp screw occurs, and the clamp screw 11 is moved from the support seat 9. Since the chip could not be removed, the amount of operation of the clamp screw at the time of chip replacement was large, and the effect of shortening the time for attachment and detachment was not sufficient.

[0005] Further, in order to enhance the holding stability of the chip, it is necessary to polish the three surfaces of the chip to enhance the adhesion to the support seat, and there has been a problem in terms of cost reduction.

[0006] Therefore, an object of the present invention is to eliminate these problems.

[0007]

According to the present invention, in order to expedite the attachment and detachment of the tip, the tip of the holder has one side of the throw-away tip as a seat bottom, and the bottom and back correspond to the respective faces. A throwaway tip is provided, in which a support seat restrained by a seat wall is provided, a throwaway tip having an upper surface and a bottom face substantially parallel is mounted on the support seat, and the tip is fixed to the holder by pressing with a clamp screw screwed into the holder. In the tip clamping mechanism, a slope which intersects with the other side of the tip at an obtuse angle and has one end reaching the rear face of the tip is provided on the upper surface of the throw-away tip, and the clamp screw is used to hold a tip bottom restraining seat wall of a support seat. And the tapered head of the clamp screw presses the slope.

This clamp mechanism tilts the rear surface of the throw-away tip and the seat wall of the support seat for restraining the rear surface in a direction in which the angle between the bottom wall and the seat wall for restraining the chip bottom surface becomes an acute angle. It is preferable that the angle formed between the seat bottom and each seat wall, the one side and the bottom surface of the throw-away tip, and the angle formed between the one side surface and the back surface are each an acute angle.

The bottom of the throw-away tip may be provided with a recess for recessing the center of the bottom in the front-rear direction of the tip, or one side of the throw-away tip may be provided with three projections for contacting the bottom of the support seat. If they are provided separately, cost can be reduced.

[0010]

According to the present invention, the clamp screw is disposed outside the chip, and the slope of the upper surface of the chip to be pressed by the tapered head of the clamp screw is opened to the back of the chip, so that the clamp screw is only slightly loosened. The tip can be removed from the support seat and replaced.

In the case where the rear surface of the chip and the rear restraint seat wall of the support seat are inclined in a direction in which the angle between the chip bottom restraint seat wall and the chip bottom restraint seat wall becomes an acute angle, the wedge effect is generated and the chip bottom surface is formed. The binding force on the back increases.

The angle between the seat bottom of the support seat and each seat wall, the one side and the bottom of the throw-away chip, and the angle between the one side and the back are acute, respectively. The wedge effect occurs in the portion, and the restraining force of the chip by the seat bottom increases.

Further, in the case where the concave portion is provided on the bottom surface of the chip, since the bottom surface of the chip comes into contact with the seat wall at two points, the holding stability of the chip can be enhanced without polishing the bottom surface, and the die molding surface can be improved. The cost can be reduced by eliminating the polishing. A chip provided with a convex portion on one side surface does not need to grind the convex portion formed by the die for the same reason, and has an effect of reducing costs.

[0014]

1 to 3 show an example in which a first embodiment of a clamp mechanism according to the present invention is applied to a boring tool.

This clamp mechanism comprises a throw-away tip 1, a holder (a shank of a cutting tool) 8, and a clamp screw 11.

The indexable insert 1 has a base 2 having a substantially parallelogram shape with an elongated projection 3 provided at the tip and a cutting edge 4 formed at the tip of the projection. Sometimes a cutting edge is attached to the blade. Here, a slope 5 which intersects the side surface 2c at an obtuse angle is provided on the upper surface 2a of the base of the throw-away tip 1. In addition to this
In the second embodiment shown in FIGS. 4 and 5, a concave portion 6 is provided on the bottom surface 2d of the base to depress the center of the surface in the front-rear direction of the chip, and three convex portions 7 shown in FIG. Provided. In both the first and second embodiments, the bottom surface 2d and the back surface 2e of the chip are inclined so that the angle formed by the side surface 2b becomes an acute angle as shown in FIGS. 8A and 8B. ing.

The holder 8 has a support seat 9 at the tip. Since the support seat is the same as in the first embodiment and the second embodiment, the description here will be made with reference to FIG. The support seat 9 is provided with two seat walls 9b and 9c rising from the seat bottom around the seat bottom 9a, and the throw-away tip 1 is mounted on the support seat 9. In addition, a screw hole 10 is provided at the tip of the holder 8 in the vicinity of the support seat 9, and a clamp screw 11 is screwed into the screw hole 10. In addition, the seat walls 9b and 9c of the support seat are inclined so that the angle formed with the seat bottom 9a becomes an acute angle corresponding to the inclination of the bottom surface 2d and the back surface 2e of the base of the chip (FIG. 8A). And FIG. 8 (b)).

The clamp mechanism according to the first embodiment and the second embodiment configured as described above is configured to tighten the clamp screw 11 and mount the tip 1 mounted on the support seat 9 with the tapered head of the screw.
Is pressurized. Thereby, the bottom surface 2d of the chip is pressed against the seat wall 9b, and the side surface 2b (or the protrusion 7) is pressed against the seat bottom 9a. Further, by tightening the clamp screw 11 in the direction of the arrow in FIGS.
e is also pressed against the seat wall 9c, and the chip 1 is fixed to the holder 8.

These clamping mechanisms include a clamping screw 1
The tip 1 can be pulled out of the holder 8 and replaced by simply loosening the tip 1 a little, and the amount of operation of the clamp screw at the time of clamping and unclamping is reduced, thereby shortening the tip replacement time.

In the second embodiment, the contact of the chip bottom surface 2d with the seat wall 9b is performed at two points on both sides of the concave portion 6 and the chip bottom 2a is dotted with the seat bottom 9a. The protrusions 7 come into contact with each other. Accordingly, the bottom surface 2d formed by the mold is used.
Even if the projections 7 are used without finishing polishing, the stability of the clamp can be ensured, and the cost can be reduced. This cost reduction effect is maximized if polishing is omitted.
Since the area of the bottom surface 2d and the convex portion 7 on both sides of the substrate is small, a certain cost reduction effect can be expected even when polishing is performed.

Although the concave portion 6 and the convex portion 7 are preferable, the object of the quick replacement of the chip can be achieved even in the configuration of the first embodiment in which these are omitted.

[0022]

As described above, the clamp mechanism of the present invention requires only a small amount of operation of the clamp screw at the time of clamping and unclamping, so that the tip exchange can be speeded up.

In the case of providing a concave portion on the bottom surface of the chip so that the bottom surface hits the seat wall of the support seat at two points, or the one having a convex portion on the side surface of the chip and allowing one side surface to hit the seat bottom at three points, The stability of the clamp can be ensured even when the contact surface with the seat is the mold forming surface, and the cost can be reduced by eliminating polishing.

[Brief description of the drawings]

FIG. 1 is a side view of a boring tool employing a clamp configuration according to a first embodiment of the present invention;

FIG. 2 is a plan view of the cutting tool;

FIG. 3 is an enlarged sectional view taken along line XX of FIG. 1;

FIG. 4 is an exploded perspective view of a boring tool employing the clamp mechanism according to the second embodiment.

FIG. 5 is a side view of the cutting tool of FIG. 4;

FIG. 6 is a side view of the indexable insert employed in the cutting tool of FIG. 4;

FIG. 7 is a perspective view of one side of the indexable tip of the above.

FIG. 8A is a cross-sectional view showing an engagement state between a seat wall of a support seat and a chip bottom surface; and FIG. 8B is a cross-sectional view showing an engagement state between a seat wall of a support seat and a chip back surface.

9A is a cross-sectional view showing a main part of a clamp mechanism previously proposed by the present applicant. FIG. 9B is a view showing the positional relationship between the clamp screw and the tip when the tip is replaced.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Throw-away tip 2 Base 2a Top surface 2b, 2c Side surface 2d Bottom surface 2e Back surface 3 Projection portion 4 Cutting edge 5 Slope 6 Concave portion 7 Convex portion 8 Holder 9 Support seat 9a Seat bottom 9b, 9c Seat wall 10 Screw hole 11 Clamp screw

Claims (5)

[Claims] 1. A support seat is provided at the tip of a holder, the support seat being restrained by a seat bottom on one side surface of the throw-away tip and a seat wall corresponding to the bottom surface and the rear surface, and the support seat has an upper surface and a bottom surface. A throw-away tip is mounted on a substantially parallel throw-away tip, and the tip is pressurized with a clamp screw screwed into a holder and fixed to the holder. The clamp screw is provided at a position where the throw-away tip is sandwiched between the support screw and the tip bottom restraining seat wall of the support seat. A clamp mechanism for a throw-away tip, wherein the slope is pressurized by a tapered head. 2. The throw away device according to claim 1, wherein the back surface of the throw away chip and the seat wall of the support seat for restraining the surface are inclined in a direction in which the angle between the back wall and the seat wall for restraining the chip bottom surface is acute. Tip clamping mechanism. 3. The throw-away tip according to claim 1, wherein an angle between the seat bottom of the support seat and each seat wall, an angle between one side and the bottom, and one side and the back of the throw-away tip are acute. Clamp mechanism. 4. The throw-away tip clamping mechanism according to claim 1, wherein a recess is formed on the bottom surface of the throw-away tip, the recess being depressed at the center of the bottom surface in the front-rear direction of the tip. 5. The clamp mechanism for a throw-away tip according to claim 1, wherein three protrusions for contacting the bottom of the support seat are dispersedly provided on one side surface of the throw-away tip.