JPH09262706A - Throwaway tool, throwaway tip and nut - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a clumping screw for securing a throwaway tip wherein a right handed screw is prevented from loosening when counterclockwise torque is acted due to cutting resistance. SOLUTION: A throwaway tool 1 whose tip 3 is given counterclockwise torque due to cutting resistance has a structure wherein a through hole 10 communicating with the mounting hole 4 of the tip 3 is bored within the tip seat 7 of a holder body 2 so that a clumping screw 11 with a right handed thread is inserted to the through hole 10 from the backside of the tip seat 7, while a nut receiving portion 5 is formed on the upper surface of the tip 3 is engaged with the nut receiving portion 5, and then the tip 3 is clumped by screwing the clumping screw 11 into the female threaded hole 12 of a nut member 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to various throw-away tools having a disposable throw-away tip, a positive rake type throw-away tip attached to the throw-away tool, and a piece member used for the throw-away tip.

[0002]

2. Description of the Related Art A conventional indexable tool 100 will be described with an end mill equipped with a positive rake type indexable insert 101. As shown in FIG. 4, the positive rake type throw-away tip 101 has an outer shape of, for example, a truncated pyramid, and has a mounting hole 102 penetrating from the front side to the back side in the central portion. on the other hand,
The holder body 103 of the throw-away tool 100 has a tip seat 1 for mounting the throw-away tip 101.
04, and a female screw hole is provided in the tip seat 104. Then, the throw-away tip 1 is placed on the tip seat 104.
01 is set and the clamp screw 105 is inserted from the front side of the mounting hole 102, and the clamp screw 105 is attached to the tip seat 1
Tighten it by screwing it into the female screw hole of 04.

The throw-away tool 100 is used for right rotation as shown by R in FIG.
In the figure, the lower right corner portion of the throw-away tip 101 receives the largest cutting resistance. Then, due to the cutting resistance, the attachment hole 10 is attached to the throw-away tip 101.
A torque of counterclockwise rotation about 2 acts.

[0004]

The clamp screw 105 for tightening the throw-away tip 101 has a right-hand screw structure and a left-hand screw structure. Since the clamp screw 105 having the right-hand screw structure tightens the throw-away tip 101 with the torque of the right rotation, when the mounting state is bad,
At, there may be a gap between the upper left corner portion of the throw-away tip 101 and the side wall 106 of the tip seat 104. As described above, with the throw-away tool 100 rotating clockwise, the throw-away tip 1 is cut by cutting resistance.
Since the counterclockwise rotation torque acts on 01, if there is such a gap between the throw-away tip 101 and the tip seat 104, the clamp screw 105 loosens and the throw-away tip 101 rotates counterclockwise by the gap. This causes movement, resulting in problems such as deterioration of processing accuracy and breakage of the throw-away tip 101.

On the other hand, the clamp screw 105 having the left-hand screw structure
Was devised to solve the above problems existing in the clamp screw 105 having a right-handed screw structure.
No. 2730), the direction of the torque that tightens the clamp screw 105 is the same as the direction of the torque that acts on the throw-away tip 101 due to the cutting resistance. Therefore, even if counterclockwise torque acts due to the cutting resistance, the throw-away tip 10
There is a feature that 1 does not move. However, the left-handed screw is generally not used for anything other than a special purpose, and there are many cases in which the operator is uncomfortable with the left-handed screw and confuses it. There was a problem that the clamp screw 105 was forcibly rotated to the right to damage both threads.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and has a positive rake type throw-away tip having a mounting hole in its center, and the throw-away tip is provided with the cutting hole by cutting resistance. In a throw-away tool having a structure in which a counterclockwise rotating torque is applied, a through hole communicating with the attachment hole of the throw-away tip is formed in the tip seat of the holder body, and the back side of the chip seat is provided in the through hole. A clamp screw having a right-handed screw structure is inserted through the upper part of the throw-away tip, and a piece receiving portion is formed on the upper surface of the throw-away tip, and a piece member having a female screw hole is fitted into the piece receiving portion. There is provided a throw-away tool adapted to clamp a throw-away tip by screwing the clamp screw into a female screw hole.

Further, in a throw-away tip mounted on a throw-away tool in such a manner that a counterclockwise rotation centered on the mounting hole is provided by a cutting resistance due to a cutting resistance, the front side of the mounting hole Form a piece receiving part on
A piece member having a female screw hole is fitted to the piece receiving portion, and the piece member is screwed into the piece member through a clamp screw having a right-hand screw structure from the back side of the through hole formed in the chip seat of the holder body.
A throw-away tip mounted on a throw-away tool by tightening the clamp screw and the piece member. In addition, it is preferable that the piece receiving portion is formed in a tapered hole shape with a narrow depth.

Furthermore, there is provided a bridge member having a tapered truncated cone as a basic shape and adapted to be fitted to the bridge receiving portion of the throw-away tip in a non-rotating structure.

[0009]

When the clamp screw is rotated to the right from the back side of the tip seat, the clamp screw is screwed into the female screw hole of the bridge member, and the throw-away tip is tightened to the front with a counterclockwise rotating torque. Therefore, the direction of the torque that tightens the clamp screw and the direction of the torque that acts on the throw-away tip due to the cutting resistance match, so even if a counterclockwise rotation torque acts due to the cutting resistance, the shift-away phenomenon of the throw-away tip does not occur. . Further, by making the basic shape of the piece member a tapered frustum shape, and by making the piece receiving portion of the throw-away tip opposite to the shape of a tapered taper hole that fits into the frustum shape, the piece member can be easily attached and detached, The throw-away tip can be replaced quickly.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 is an exploded perspective view showing an essential part of the throw-away tool, FIG. 2 is a front view showing an essential part of the throw-away tool, and FIG. 3 is a sectional view taken along line XX of FIG.

The illustrated throw-away tool 1 is an end mill, and two end mills are provided at the tip of a round shaft-shaped holder body 2 and in a point-symmetrical manner about the axis O (see FIG. 3) of the holder body 2. It has throw-away chips 3 and 3. The throw-away tool 1 rotates right about the axis O as shown by the arrow R in FIG.

The throw-away tip 3 is a so-called positive rake type in which a corner is rounded and chamfered into a quadrangular truncated pyramid shape, and a mounting hole 4 penetrating from the front side to the back side is provided in the central portion. In the attachment hole 4 of the throw-away tip 3, a piece receiving portion 5 having a tapered inner hole shape is formed on the front side. The piece receiving portion 5 is a female type having a substantially quadrangular shape in a front view, which is paired with a square truncated pyramid shape of a piece member 6 described later. The inner surface of the piece receiving portion 5 is an arcuate rounded surface A as shown in FIG. Due to the rounded surface A of the piece receiving portion 5, it is possible to flexibly cope with the piece member 6 having a slightly different taper degree and size.

On the other hand, the holder body 2 is provided with a tip seat 7 for mounting the throw-away tip 3. The tip seat 7 has an upper wall 8 and a side wall 9 surrounding the upper side surface and the left side surface of the throw-away tip 3 in FIG. 1, and has a through hole 10 communicating with the attachment hole 4 of the throw-away tip 3 in the central portion. It is drilled.

Thus, the throw-away tip 3 is
The piece member 6 and the clamp screw 11 clamp the chip seat 7. The piece member 6 has a quadrangular truncated pyramid shape with a tapered basic shape, has a round shaft portion 6a at its narrowed tip, and has an internal threaded hole 12 in a state of penetrating the center portion. on the other hand,
The clamp screw 11 has a normal right-handed screw structure having a round head 11a at its end, and can be screwed into the female screw hole 12 of the piece member 6.

Next, a method of mounting the throw-away tip 3 will be described. First, the piece member 6 is fitted into the piece receiving portion 5 of the throw-away tip 3. As described above, since the piece receiving portion 5 is a female type having a quadrangular pyramid shape that is paired with the square pyramidal shape of the piece member 6, the piece member 6 is fitted in the piece receiving portion 5 in a non-rotating structure. Next, the throw-away tip 3 is set in the tip seat 7 of the holder body 2, and the clamp screw 11 is inserted into the through hole 10 of the holder body 2 from the back side of the tip seat 7. Then, when the clamp screw 11 is rotated clockwise from the back side of the tip seat 7, the clamp screw 11 is screwed into the female screw hole 12 of the piece member 6 and tightens the throw-away tip 3 with a counterclockwise rotating torque. Therefore, since the direction of the torque that tightens the clamp screw 11 and the direction of the torque that acts on the throw-away tip 3 due to the cutting resistance match, the shift-away phenomenon of the throw-away tip 3 even when the counterclockwise rotation torque acts due to the cutting resistance. Does not happen.

Although the present invention has been described above with reference to the embodiments, the present invention is of course not limited to the above embodiments. For example, the throw-away tool includes, in addition to the exemplified end mill, a rotary tool such as a drill and a turning tool for rotating and cutting the work side. In the case of a turning tool, it is a so-called right-handed type in which a counterclockwise rotating torque acts on the throw-away tip due to cutting resistance.

The shape of the throw-away tip is not limited to the square in the front view of the embodiment, but may be a triangle, a rhombus, a circle, or the like. When the throw-away tip has a triangular shape or a diamond shape when viewed from the front, it is preferable that the piece receiving portion and the piece member also have a similar triangular shape or a diamond shape. By doing so, each corner of the throw-away tip can be effectively used. Further, the shape of the piece receiving portion and the piece member can be elliptical as well as polygonal in a front view. Furthermore, the piece member may have a straight cylindrical shape instead of the frustum shape, and in that case, the piece receiving portion need not have a tapered hole shape.

[0018]

According to the present invention, since the clamp screw having the right-handed screw structure is passed through from the back side of the tip seat to be screwed into the bridge member, and the throw-away tip is tightened with the torque of the counterclockwise rotation toward the front, the cutting is performed. Even if a counterclockwise rotation torque is applied due to resistance, the throw-away tip does not move, and the clamp screw has a familiar right-hand screw structure, so there is no risk that the operator will make a mistake in the tightening direction. Also, the screw thread is not damaged due to excessive reverse rotation.

Further, the basic shape of the piece member is a tapered frustum shape, and the piece receiving portion of the throw-away tip opposite thereto is a tapered taper hole shape that fits into the frustum shape.
The effect is that the piece member can be easily attached and detached, the throw-away tip can be replaced quickly, and the piece receiving portion can be easily cleaned.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a main part of a throw-away tool.

FIG. 2 is a front view showing a main part of a throw-away tool.

FIG. 3 is a sectional view taken along line XX of FIG. 2;

FIG. 4 is a perspective view of a main part showing a conventional technique.

[Explanation of symbols]

 1 ... Throw-away tool 2 ... Holder body 3 ... Throw-away tip 4 ... Mounting hole 5 ... Piece receiving part 6 ... Piece member 7 ... Tip seat 10 ... Through hole 11 ... Clamp screw 12 ... Female screw hole

Claims (4)

[Claims] 1. A throw having a structure in which a positive rake type throw-away tip having a mounting hole in the center thereof is provided, and a counterclockwise rotation torque about the mounting hole acts on the throw-away tip due to cutting resistance. In the away tool, a through hole communicating with the attachment hole of the throw-away tip is formed in the tip seat of the holder body, and a clamp screw having a right-handed screw structure is inserted into the through hole from the back side of the tip seat.
On the other hand, a piece receiving portion is formed on the upper surface of the throw-away tip, and a piece member having a female screw hole is fitted into the piece receiving portion, and the clamp screw is screwed into the female screw hole of the piece member. A throw-away tool that clamps the throw-away tip. 2. A throw-away tip mounted on a throw-away tool in such a manner that a mounting hole is formed at the center thereof and a counterclockwise rotation centering on the mounting hole acts on the cutting resistance due to cutting resistance, the front side of the mounting hole. A piece receiving portion is formed in the piece, a piece member having an internal thread hole is fitted in the piece receiving portion, and a piece of screw member is screwed into the piece member from the back side of the through hole formed in the tip seat of the holder body through a clamp screw having a right-hand screw structure A throw-away tip that is attached to a throw-away tool by tightening the clamp screw and the piece member. 3. The throw-away tip according to claim 2, wherein the piece receiving portion has a tapered hole shape with a narrow inner diameter. 4. A bridge member having a basic shape of a tapered frustum and adapted to be fitted into the bridge receiving portion of the throw-away tip according to claim 3 in a non-rotating structure.