JP2002144112A - Clamp mechanism for disc-like throwaway tip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To center and fasten a tip without impairing durability of a tip mounting member. SOLUTION: Cutouts 25F are provided in positions opposite to each other with respect to the center axis O in the peripheral surface of a pressing part of the tip 25. When a clamp screw 28 penetrating through the tip 25 is screwed, the pressing part elastically deform the peripheral wall part 24B outward, whereby in addition to fastening the pressing part, the peripheral wall part 24B which is not pressed is elastically deformed inward (S direction) due to existence of the cutouts 25F in the pressing part.

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 detachably attaching a disc-shaped indexable insert (hereinafter referred to as an insert) to a tip of a cutting tool or the like.

[0002]

2. Description of the Related Art Conventionally, as a disc-shaped tip clamping mechanism of this type, one disclosed in Japanese Patent No. 2846020 is known. Such a clamp mechanism has a disk-shaped chip whose peripheral surface is formed in a truncated cone shape as a pressing portion, and a chip mounting seat having a truncated cone-shaped recess at an upper portion for mounting the chip. And a chip mounting member made of a material that can be elastically deformed, and further, a notch is provided radially toward the center of the peripheral wall of the concave portion of the chip mounting seat and divided into a plurality of segments. Things.

[0003] The clamp mechanism constructed as described above fits the truncated cone-shaped pressing portion of the tip to a tip mounting seat having a truncated conical recess provided at the top of the tip mounting member. The tip is pressed by such a clamping means. Here, since the notch is provided in the chip mounting seat, it is easy to be elastically deformed, and the pressing portion of the chip moves downward while being guided by the inner peripheral surface of the concave portion of the chip mounting seat, and is clamped. The chip is pressed against the bottom surface of the chip mounting seat by the pressing force of the piece and is fixed at that position, so that the centering and fastening of the chip are simultaneously performed.

[0004]

However, in the above-described clamp mechanism, the notch is provided in the chip mounting seat, so that the durability of the chip mounting member is weakened and the mounting rigidity of the chip is also weakened. There was a problem that would be.

The present invention has been made in view of the above problems, and has as its object to provide a disk-shaped chip clamping mechanism capable of centering and fastening a chip without impairing the durability of the chip mounting member. And

[0006]

Means for Solving the Problems To solve the above problems,
In order to achieve such a purpose, at the tip of the tool body,
In a clamping mechanism having a bottom plate portion and a peripheral wall portion and provided with a disc-shaped throw-away tip for inserting and inserting a disc-shaped throw-away tip, in the clamp mechanism for detachably attaching the throw-away tip by clamping means, A pressing portion for pressing the peripheral wall portion of the chip mounting member is formed on the peripheral surface thereof, and a plurality of notches are provided at intervals on the peripheral surface of the pressing portion, and the notch is inserted into the chip mounting seat. When the throw-away tip is pressed by the clamp means, the peripheral wall portion is pressed by the pressing portion to be elastically deformed, and the throw-away tip is positioned and held.

According to the present invention, when the chip is clamped by the clamping means and the pressing portion of the chip presses the peripheral wall of the chip mounting member, the notch is provided in the pressing portion of the chip. Therefore, the entire periphery of the pressing portion does not come into contact with the peripheral wall of the chip mounting member, and the portion provided with the notch does not press the peripheral wall. Thereby, the stress applied to the peripheral wall portion of the chip mounting member can be absorbed by the portion of the peripheral wall portion facing the notch of the pressing portion being elastically deformed to the notch side, and the peripheral wall portion bends, The tip can be fastened with a smaller clamping force than before. In addition, since a plurality of notches are provided on the peripheral surface of the pressing portion, there are also a plurality of pressed peripheral wall portions, each of which is elastically deformed and the chip is tightened in the direction of the central axis,
The centering of the chip can be easily performed. Further, the notch is not provided in the chip mounting member, and the chip mounting member can have higher mounting rigidity without deteriorating the durability of the chip mounting member as compared with the conventional one in which the notch is provided in the chip mounting seat. .

Further, the present invention provides a method for cutting a work material by a cutting blade of the indexable insert, which is supported on an upper part of a sheet member rotatable with respect to a tool body so as to be coaxially rotatable with the sheet member. On the other hand, the indexable tip can be used more effectively by being attached to a rotary tool that is driven to rotate with the tip attachment member and the sheet member.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1A is a plan view of a rotary tool using the clamp mechanism according to the present embodiment, FIG. 1B is a side view of the rotary tool, and FIG.
, FIG. 3 is a cross-sectional view of a chip mounting member of the rotary tool, FIG. 4A is a plan view of a chip mounted on the rotary tool as viewed from above, and FIG.
5A is a plan view of the chip as viewed from below, FIG. 5A is a side view of the chip in FIG. 4 viewed from the direction A, and FIG. 5B is a side view of the chip as viewed from the direction B.

In the rotary tool according to the present embodiment, as shown in FIGS. 1 and 2, a blind hole-shaped mounting hole 13 is formed at the tip end portion 12 of the tool body 11 obliquely from the upper surface to the lower surface. The bearing member 14 is formed in the mounting hole 13 so that a tip (upper end) portion 14A is formed in a flange shape whose diameter is increased by one step from the cylindrical body portion 14B.

The bearing member 14 has a recess 14C formed in a body 14B thereof.
2 is inserted into a through hole 12A formed to open at the position of the concave portion 14C.
Is fixed to the mounting hole 13 by engaging with the mounting hole 13.

On the inner periphery of the bearing member 14, a substantially columnar sheet member 17 whose front end (upper end) portion 17A is enlarged by one step via a radial bearing 16.
7B and the bearing member 1
4 and the front end 1 of the sheet member 17.
A thrust bearing 18 is interposed between the lower surface of the seat member 7A and the seat member 1.
7 is supported so as to be rotatable around its central axis O.

At the rear end 17C of the sheet member 17,
A disk-shaped receiving plate 19 is attached to the tip portion 17A side with attachment screws 21 and 21 with a thrust ball bearing 20 interposed therebetween, and attached to the rear end opening of the thrust ball bearing 20 and the bearing member 14. The disc spring 23 is inserted in a compressed state between the disc spring 23 and the ring-shaped disc spring receiving member 22. Along with 19, it is urged toward the rear end side in the central axis O direction.

On the other hand, a circular fitting hole 17E centered on the center axis O is formed at the center of the upper surface 17D of the front end portion 17A of the sheet member 17 so as to be recessed one step from the upper surface 17D. At the center of the bottom surface of the hole 17E, a mounting screw hole 17F is formed along the central axis O.
Further, on the upper surface 17D, a sheet-side detent pin groove 17G for engaging a detent pin 27 for preventing the chip mounting member 24 from slipping on the sheet member 17 is formed in a straight line passing through the central axis O. I have.

The tip 12 of the cutting tool body 11 includes
A mounting hole 12C is formed from the upper surface 12B through an oil passage 12D.
Drilled to communicate with a through hole 14D formed in the body 14B of the bearing member 14, the grease nipple 30 attached to the mounting hole 12C passes through the oil passage 12D and the through hole 14D to form the bearing member 14 with the bearing member 14. Lubricating oil is supplied between the seat member 17 and the shaft portion 17B.

The tip attachment member 24 attached to the front end portion 17A of the sheet member 17 is made of a material that is relatively easily deformed, such as a spring rope, and has a center axis O as shown in FIG. A bottom plate portion 24A having a substantially circular plate shape and a peripheral wall portion 24B formed so as to orbit around the peripheral edge of the bottom plate portion 24A around the central axis O, and have a bottomed annular shape. Thereby, the bottom plate portion 24
A chip mounting seat 26 is formed such that the upper surface of A is a bottom surface 26A and the inner peripheral surface of the peripheral wall portion 24B is a wall surface 26B. Further, as the upper side of the wall surface 26B of the chip mounting seat 26 goes upward, the inner surface is formed as a tapered surface 26C whose inner diameter gradually increases. Also, this bottom plate portion 24
In the center of A, a circular insertion hole 24 is formed along the central axis O.
C penetrates, and further, on the lower surface 24D of the bottom plate portion 24A, an annular fitting portion 24E centering on the center axis O is formed at the periphery of the insertion hole 24C so as to protrude downward. The outer diameter of the fitting portion 24E is equal to the fitting hole 1 of the sheet 17.
7E.

Then, the tip mounting member 24 is
4E is fitted into a fitting hole 17E formed in the center of the front end of the sheet member 17. Here, the concave portion 24 is formed in the fitting portion 24E.
G is formed, and a screw hole 1 is formed in the front end portion 17A of the sheet member 17 so as to open at the position of the concave portion 24G.
The tip of the fixing screw 29 screwed into the 7H is a concave portion 24G.
Is fixed to the sheet member 17. Further, the two insertion holes 24 opposed to the bottom plate portion 24A of the tip mounting member 24 at a fixed distance from the central axis O.
F, 24F are provided, and the insertion holes 24F, 24F are provided.
The lower ends of the substantially cylindrical detent pins 27, 27 for slip prevention inserted into the F are engaged with the sheet-side detent pin grooves 17G of the sheet member 17, and the upper end thereof is rotated around the tip side of the chip 25. The engagement with the retaining pin groove 25H prevents the chip 25, the chip mounting member 24, and the sheet member 17 from slipping with each other.

The chip 25 to be mounted on the chip mounting seat 26 is formed of a hard material such as a cemented carbide and has a substantially disc shape, and has a circular shape as shown in FIGS. The upper surface is a rake surface 25A, and a tapered surface formed on the upper part of the outer peripheral surface so as to reduce the diameter toward the upper side is a flank 25B.
5B and the rake face 25A, the circular cutting edge 25
C is formed. On the outer peripheral edge of the upper surface of the chip 25, a groove-shaped chip breaker 25D is provided with a cutting edge 25C.
It is formed so as to go around. Further, the lower portion of the tip 25 is formed by a tapered surface 26C of the tip mounting seat 26.
Accordingly, the diameter of the tapered surface is gradually reduced toward the lower side, and a lower portion of the tapered surface is a pressing portion 25E.

In the pressing portion 25E of the chip 25, two notches 25F, 25F are provided on the peripheral surface at positions facing each other with respect to the central axis O.
When the is set in the chip mounting seat 26, the notch 25
F, 25F and the tapered surface 26C of the chip mounting seat 26 are kept out of contact with each other with a slight gap. In the center of the tip 25, a clamp hole 25G through which a clamp screw 28 as a clamp means in the present embodiment passes is formed along the axis O. Further, on the lower surface 25I of the chip 25, a detent pin 27 for preventing the chip 25 from slipping with respect to the chip mounting member 24,
Groove 2 for chip detent pin for engaging with 27
5H is provided so as to connect the notches 25F, 25F and the central axis O, and penetrates through the insertion hole 24F provided in the chip mounting member 24 so that the upper ends of the detent pins 27, 27 are engaged. Have been.

Next, a description will be given of a method for mounting the tip of the rotary tool having the above configuration. FIG. 6 shows a non-clamp state of the clamp mechanism according to the present embodiment,
4 is a sectional view taken along line YY of the chip shown in FIG. 4, FIG. 7 is a sectional view taken along line XX of the chip shown in FIG. 4, and FIG. 8 is a sectional view showing a clamped state of the clamp mechanism according to the present embodiment. 4 is a cross-sectional view taken along the line YY of the chip shown in FIG. 4, and FIG.
10 is a sectional view taken along line WW in FIGS. 8 and 9. (In FIGS. 6 to 9, the groove 17G for the sheet-side detent pin, the groove 25H for the chip-side detent pin, the detent pin 27, and the insertion hole 24F for the chip mounting member 24.
Is not shown. )

First, as shown in FIGS. 6 and 7, the chip 25 is set on the chip mounting seat 26 of the chip mounting member 24, and passes through the clamp hole 25G of the chip 25 and the insertion hole 24C of the chip mounting member 24. Then, the clamp screw 28 is screwed into the clamp screw hole 17F of the sheet member 17. Before screwing this clamp screw 28, as shown in FIG. 6, the tapered surface 26C of the chip mounting seat 26 and the pressing portion 25E of the chip 25 are in surface contact, and the notches 25F, 25F are as shown in FIG. At the same time, it is not in contact with the tapered surface 26C.

Then, the chip 25 and the chip mounting member 24
The tip 25 is moved downward by screwing in the clamp screw 28 penetrating the tip mounting seat, and the pressing portion 25E of the tip 25 is in surface contact with the tip mounting seat as shown in FIGS. By pressing the tapered surface 26C of the chip 26, the peripheral wall 24B of the chip 24 is elastically deformed so as to be pushed outward (in the direction T), and the pressing portion 25E is tightened to the peripheral wall 24B. At this time, as shown in FIGS. 9 and 10, the notch 25F, 25F is provided on the peripheral surface of the pressing surface 25E of the chip 25, so that the peripheral wall portion 24B of the chip mounting member 24 that does not contact the pressing portion 25E. Is elastically deformed inward (S direction), and the stress applied to the peripheral wall portion 24B can be released at this portion.

Subsequently, by inserting the clamp screw 28, the chip 25 is pressed and fixed to the bottom surface 26 A of the chip mounting seat 26. At this time, the peripheral wall portion 24B of the chip mounting seat 24 is elastically deformed to tighten the chip 25, so that the center axis of the chip 25 coincides with the center axis of the chip mounting member 26, that is, the center axis O of the sheet member 17. The tip 25 is positioned and positioned as described above, and the mounting of the chip 25 is completed.

According to this embodiment, the chip 2
5 is provided with two notches 25F, 25F at positions opposing the central axis O on the peripheral surface of the pressing portion 25E, so that the entire periphery of the pressing portion 25E is formed on the peripheral wall portion 24B of the chip mounting member 24. Not contact, but notch 25F, 2
The portion where 5F is provided does not contact the peripheral wall portion 24B. As a result, the stress applied to the peripheral wall portion 24B of the chip mounting member 24 can be released at a portion where the notches 25F and 25F are provided and the pressing portion 25E does not contact the peripheral wall portion 24B, and the peripheral wall portion 24A is easily bent. The tip 25 can be fastened with a smaller clamping force than before. The notches 25F, 25F are provided on the peripheral surface of the pressing portion 25E at positions facing the central axis O, and the peripheral wall portion 24B to be pressed is also located at the position facing the central axis O, and each of the notches 25F is elastically deformed and deformed. Since the chip 25 is tightened in the O direction, the centering of the chip 25 can be easily performed. Further, when such a clamp mechanism is used, the durability of the chip mounting member 24 is not impaired as compared with the conventional one in which the notch is provided in the chip mounting seat 26,
The mounting rigidity of the chip 25 can be increased.

In the rotary tool having such a configuration, the tip 25 is provided with a negative front rake angle (for example, 24 °) as shown in FIG.
And a negative side rake angle (for example, 24 °) is provided to be inclined with respect to the reference plane, and the outer diameter of the work material is cut by the cutting edge 25C. The chip 25 itself is also driven and rotated about the central axis O together with the chip mounting member 24 and the sheet member 17 by the cutting force, thereby reducing the cutting resistance and also reducing the frictional resistance between the chip 25 and the work material. Thus, wear of the chip 25 is suppressed.

In this embodiment, the clamp screw 28
Thus, the pressing portion 25E of the chip 25 to be pressed is in surface contact with the tapered surface 26C of the chip mounting seat 26. However, the present invention is not limited to this, and may be line contact or point contact.

In this embodiment, the number of the notches 25F provided on the pressing surface 25E of the chip 25 is two. However, the present invention is not limited to this. The notch 25F may be formed.

Although the clamp mechanism according to the present embodiment is applied to a rotary tool, the present invention is not limited to this, and can be applied to other tools that use a disk-shaped tip in a fixed state.

[0029]

According to the present invention, a pressing portion for pressing the peripheral wall portion of the tip mounting member is formed on the peripheral surface of the throw-away tip, and a plurality of cuts are formed on the peripheral surface of the pressing portion at substantially constant intervals. By being provided with a notch, the chip is pressed by the clamp means, and when the pressing portion of the chip presses the peripheral wall portion of the chip mounting member, the entire periphery of the chip pressing portion is formed by the chip mounting member. Instead of pressing the peripheral wall, the portion provided with the notch does not press the peripheral wall. Thereby, the stress applied to the peripheral wall of the tip mounting member can be absorbed by the elastic deformation of the portion of the peripheral wall facing the notch of the pressing portion, and the peripheral wall can be easily bent. The chip can be fastened by force. Further, since a plurality of notches are provided on the peripheral surface of the pressing portion, there are also a plurality of peripheral wall portions to be pressed,
Since the chips are tightened in the direction of the center axis, respectively, the centering of the chips can be easily performed. Further, the chip mounting member is not provided with a notch, so that the chip mounting seat can be increased in rigidity without deteriorating the durability of the chip mounting seat as compared with the conventional one in which the notch is provided in the chip mounting seat. .
Further, the present invention can be used more effectively by being attached to a rotary tool.

[Brief description of the drawings]

FIG. 1A is a plan view of a rotary tool using a clamp mechanism according to the present embodiment, and FIG. 1B is a side view of the rotary tool.

FIG. 2 is a sectional view taken along line ZZ in FIG.

FIG. 3 is a sectional view of a tip mounting member of the clamp mechanism according to the embodiment.

FIG. 4A is a plan view of the tip of the clamp mechanism according to the present embodiment as viewed from above, and FIG. 4B is a plan view of the tip as viewed from below.

5A is a side view of the chip in FIG. 4 as viewed from a direction A, and FIG. 5B is a side view of the chip as viewed from a direction B.

6 shows a non-clamp state of the clamp mechanism according to the present embodiment, and is a cross-sectional view of the chip shown in FIG. 4, taken along line YY.

7 shows a non-clamp state of the clamp mechanism according to the present embodiment, and is a cross-sectional view of the tip shown in FIG. 4 along the line XX.

8 is a sectional view of the tip shown in FIG. 4, taken along the line YY, showing a clamp state of the clamp mechanism according to the present embodiment.

FIG. 9 is a sectional view of the tip shown in FIG. 4, taken along line XX, showing a clamped state of the clamp mechanism according to the present embodiment.

FIG. 10 is a sectional view taken along line WW in FIGS. 8 and 9;

[Explanation of symbols]

 11 byte body 12 tip part 14 bearing member 17 seat member 24 chip mounting member 24A bottom plate part 24B peripheral wall part 24C insertion hole 24E fitting part 25 chip 25E pressing part 25F notch 25G clamp hole 26 chip mounting seat 26A bottom surface 26B wall surface taper 26C Surface 28 Clamp screw O Center axis

Claims (2)

[Claims] 1. A tip mounting member having a bottom plate portion and a peripheral wall portion for inserting a disc-shaped throw-away tip is provided at a tip end of a tool body, and the throw-away tip is detachable by a clamp means. In the clamp mechanism to be mounted on the throw-away tip, a pressing portion for pressing a peripheral wall portion of the tip mounting member is formed on a peripheral surface thereof, and a plurality of notches are provided on the peripheral surface of the pressing portion at intervals. By pressing the throw-away tip inserted in the tip mounting seat by the clamping means, the peripheral wall portion is pressed by the pressing portion and elastically deformed, and the throw-away tip is positioned and held. A disc-shaped throw-away tip clamping mechanism. 2. The disc-shaped indexable insert clamping mechanism according to claim 1, wherein the clamp mechanism is supported on an upper portion of a sheet member rotatable with respect to a tool body so as to be integrally rotatable coaxially with the sheet member. A disc-shaped cutting tool which is attached to a rotary cutting tool which is driven to rotate with the tip attaching member and the sheet member while cutting the work material with the cutting edge of the throw-away tip. The indexable tip clamp mechanism.