JPH11104904A - Tool holder for grooving and throwaway tip thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a clamping rigidity and to secure a use of cutting edges provided on both sides, at all times by positioning a rear end of a grooving use throwaway tip, which is a two corner type and has the cutting edges at both sides, along a longitudinal axial direction thereof without being in contact with a holder main body. SOLUTION: A tip seat portion 5 having a v-shaped groove section and a stemming portion 6 cut in recessed shape are formed at a submaxillary portion 4 of a holder main body 1. An upper part press portion 10 having a v-shaped protrusion section and a side part press portion 11 neighboring on the upper part press portion are formed at a tip of a maxilla portion 3. A contact surface, which carries out positioning of the throwaway tip 12 along a longitudinal axial direction X, is formed at the side part press portion 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grooving tool holder used for grooving an outer periphery of a work material and a throw-away tip thereof.

[0002]

2. Description of the Related Art FIG. 5 is a perspective view showing an example of a conventional grooving tool holder.

[0005] In FIG. 5, a throw-away tip 21 for grooving having a rectangular parallelepiped basic shape is mounted on the tip side of a square rod-shaped holder body 20. Cutting edges are formed at both ends in the major axis direction of the throw-away tip 21, and mounting engagement surfaces 22, 23 are formed on the upper and lower surfaces thereof, respectively.

The mounting engagement surface 22 on the upper surface side is formed on the upper surface of the convex portion at the center of the throw-away tip 21,
It has a V-projection. On the other hand, the mounting engagement surface 23 on the lower surface side is formed over the entire area in the long axis direction, and presents a V-groove in a sectional view. The apex angle of each of the V-projection and the V-groove is set in consideration of the strength of the throw-away tip 21, stability of seating, lateral displacement, and the like.

[0005] The tip side of the holder body 20 is divided into a lower jaw 25 and an upper jaw 26 by an elongated slit 24. In front of the opening end of the slit 24, the lower jaw 2
5, a tip mounting seat 27 for mounting the throw-away tip 21 is formed, and a pressing portion 28 for pressing the upper surface of the convex portion of the throw-away tip 21 is formed in the upper jaw 25.

The throw-away tip 21 is fitted between the tip mounting seat 27 and the pressing portion 28, and is long in a state where the rear end portion having the cutting edge is in line or surface contact with the rear wall surface 29 of the tip mounting seat 27. Axial positioning is achieved. By tightening the tightening screw fitted into the center mounting hole of the upper jaw 26, the pressing portion at the tip of the upper jaw 26 is bent downward by elastic deformation, and the throw-away tip 21 is pressed and fixed.

[0007] In the grooving tool holder having such a configuration, in particular, the tip 2 having cutting edges at both ends.
1 can be mounted, and tool cost can be reduced.

[0008]

Here, the problems of the prior art will be described below.

In the grooving tool holder, one end of a throw-away tip 21 having a cutting edge is attached to the holder body 20.
The position of the throw-away tip 21 in the long axis direction is restrained by the rear wall surface 29 of the tip mounting seat 27.

However, when a throw-away insert having a front cutting edge angle (hereinafter referred to as a "hand-drawn throw-away tip") is attached, it comes into point contact with the rear wall surface, and the cutting resistance in the long axis direction ( Hereinafter, it is referred to as “back force”.)
Depending on the size of the cutting edge, the cutting edge may move. In addition, even when a non-reliable indexable insert is used, the grooving depth may be changed by being shifted backward in the longitudinal direction by the retreat amount of the cutting edge due to wear or loss of the previously used cutting edge. Furthermore, if the contact between the rear end of the throw-away tip 21 and the rear wall 29 of the mounting seat is poor, chipping or chipping may occur due to rattling or the like. In some cases, it had to be disposable without using the other cutting edge.

[0011]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above-mentioned problems, and has an upper jaw and a lower jaw divided into upper and lower parts by slits at the tip side of a square rod-shaped holder main body. Is formed, a pressing portion for pressing the upper surface of the throw away tip is provided at the tip of the upper jaw,
In the lower jaw, a chip seat for mounting the throw-away tip is formed in a notched mounting step, and by tightening a tightening screw that fits into the mounting hole in the center of the upper jaw.
In the grooving bite holder in which the throw-away tip is pressed and fixed, the lower jaw portion of the holder body includes a tip seating portion having a V-groove-shaped cross section and a recessed notched portion. On the other hand, the pressing portion formed at the tip of the upper jaw includes an upper pressing portion having a V-shaped cross section and a side pressing portion adjacent to the upper pressing portion. The part pressing portion 11 is characterized in that a contact surface for positioning the throw-away tip in the major axis direction X is formed.

The throw-away tip has a rectangular parallelepiped basic shape, and a contact surface having a V-shaped cross section is formed on the lower surface over the entire area in the longitudinal direction. A protruding portion is formed,
A contact surface having a V-groove cross section is formed on the upper surface of the convex portion substantially in parallel with the lower surface, and a contact surface formed of an inclined surface gradually descending to both ends of the throw-away tip is formed on the side surface of the convex portion. The surface is formed.

[0013]

Next, an embodiment of the present invention will be described with reference to the drawings.

In FIGS. 1 to 3, a holder body 1 is shown.
Has a rectangular rod shape, and its tip side is divided into an upper jaw 3 and a lower jaw 4 by an elongated slit 2 extending in the long axis direction X.

The lower jaw 4 has a throw-away tip 12
A chip seat 5 for mounting a chip (hereinafter referred to as a “chip”) is formed in front of the slit 2, and a concave slim portion is formed behind the chip seat 5 to enhance the stability of seating of the chip 12. 6 are formed adjacent to each other. The chip seating portion 5 is elongated and protruded forward along the side of the holder main body 1, and at the same time, in order to position the chip 12 in the short axis direction X, a V groove adapted to the lower surface 14 of the chip 12. It has a cross section of a shape. A mounting hole 8 for a tightening screw 7 is drilled obliquely rearward of the knurled portion 6.

The upper jaw 3 is provided with a pressing portion 9 formed by a notch at an elongated protruding tip facing the chip seating portion 5. The pressing portion 9 is provided on the upper surface 1 of the convex portion of the chip 12.
6 and a side pressing portion 11 that contacts the side surface 17 of the convex portion. The upper pressing portion 10
It has a V-shaped cross section so as to fit with the upper surface 16 of the convex portion of the chip 12, and is provided so as to face parallel to the chip seating portion.

The side pressing portion 11 is formed adjacent to the upper pressing portion 10 and is formed as an inclined surface which becomes gradually lower toward the bottom surface side of the holder main body 1 as the distance from the rear of the holder main body 1 increases. . The inclined surface forms an angle γ with a direction parallel to the upper surface of the projection, and has a width substantially equal to the width of the chip.

At the rear of the pressing portion 9, a mounting hole 8 for inserting the tightening screw 7 is formed. The tightening screw 7 vertically crosses the slit 2 and is screwed with the lower jaw 4. By tightening the tightening screw 7, the pressing portion 9 at the tip of the upper jaw 3 tilts forward and abuts on the convex upper surface 16 and the convex side surface 17 formed in the center of the body on the upper surface of the chip 12, The positioning of the chip 12 in the short axis direction X and the long axis direction Y is performed.

FIG. 4 shows a chip 12 having a rectangular parallelepiped basic shape, and cutting edges 13 are formed at both ends in the major axis direction X.

On the upper surface side of the chip 12, a convex portion 15 projecting from the center of the body of the chip 12 is formed.
The convex side surface 17 abuts on the upper pressing portion 10 and the side pressing portion 11 of the upper jaw 3. The upper surface 16 of the convex portion which comes into contact with the upper pressing portion 10 of the upper jaw 3 has a V-shaped cross section, and the apex angle α of the V-shaped groove is a predetermined angle α in consideration of the strength of the chip and the stability of mounting. The angle is set. The convex side surface 17 that contacts the side pressing portion 11 of the upper jaw 3 is formed on both sides of the convex upper surface 16 and forms an inclined surface that gradually descends toward both ends of the throw-away tip 12.

Since the tip 12 of the present invention is of a two-corner type having a rectangular parallelepiped basic shape, the tip 12 is detached when the sharpness of the cutting edge 13 at one end becomes poor or is lost. The end cutting edge 13 can be used, which is economical. In addition, the grooving cutting tool according to the present invention is based on the convex side surface 11 of the chip 12.
The positioning in the major axis direction X is performed, and stable clamp rigidity can be maintained without being affected by the shape of the cutting edge. Also, the other cutting edge 1 is always used without being affected by the damage state of the one cutting edge 13 used.
3 can be secured.

[0022]

As described above, according to the present invention, the positioning in the long axis direction can be performed without restraining the rear end of the chip having the cutting edges at both ends by the pressing portion formed at the tip of the upper jaw of the holder body. Can do it. Thus, the clamp rigidity can be maintained, and even when one end of the throw-away tip is lost due to loss, the cutting edges at both ends can be used effectively without wasting the other end.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a grooving tool holder according to the present invention.

FIG. 2 is a view showing a grooving tool holder shown in FIG. 1;
(A) is a plan view, (b) is a front view, and (c) is a side view.

FIG. 3 is an enlarged front view of a distal end portion of the holder main body shown in FIG.

4A and 4B are diagrams showing one embodiment of the throw-away tip of the present invention, wherein FIG. 4A is a plan view, FIG. 4B is a front view, and FIG. 4C is a side view.

FIG. 5 is a perspective view showing an example of a conventional grooving tool holder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Holder main body 2 Slit 3 Upper jaw part 4 Lower jaw part 10 Upper pressing part 11 Side pressing part 12 Throw away tip 16 Convex upper surface 17 Convex side surface

Claims (2)

[Claims] An upper jaw 3 and a lower jaw 4 are formed on a tip side of a holder body 1 having a square rod shape and are vertically divided by a slit 2. The lower jaw 4 is provided with a tip seating portion 5 for mounting the throw-away tip 12 formed in a notched mounting step, and a mounting hole in the center of the upper jaw 3 is provided. The lower jaw 4 of the holder main body 1 is provided with a V-shaped groove in the grooving tool holder in which the throw-away tip 12 is pressed and fixed by the tightening of the tightening screw 7 fitted in the lower portion 8. Chip seating part 5 having a cross section and dent part 6 notched in a concave shape
Are formed adjacent to each other, while the pressing portion 9 formed at the tip of the upper jaw 3 includes an upper pressing portion 10 having a V-shaped cross section and a side pressing portion 1 adjacent to the upper pressing portion.
1. A grooving tool holder characterized in that the side pressing portion 11 is formed with a contact surface for positioning the throw-away tip 12 in the major axis direction X. 2. A throw-away chip mounted on the grooving tool holder according to claim 1, wherein the contact surface has a rectangular parallelepiped basic shape, and a lower surface has a contact surface having a V-shaped cross section. A convex portion 15 is formed over the entire region in the major axis direction X, and a convex portion 15 is formed on the upper surface side and protrudes from the center of the body of the throw-away tip 12. The throw-away tip 1 is formed substantially parallel to the lower surface 14 and has a convex side surface 17.
2. A throw-away tip, wherein a contact surface comprising an inclined surface that gradually descends toward an end of the second insert is formed.