JPH0112885Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to a cutting tool using a regular polygonal indexable tip with a center hole, and particularly to an indexing tool having an automatic cutting blade exchange function.

(b) Conventional technology and its problems Conventionally, in throw-away cutting tools equipped with indexable tips with a center hole, the cutting edge of the tip has generally been replaced manually, just as in the case of tips without holes. be. That is, the throw-away chip is usually fixed by passing a lever pin, which is swung by an eccentric shaft or an operating bolt, through its center hole, and then loosening the clamping eccentric shaft or pin using a spanner or the like. Afterwards, the tip is picked up with the fingertips, rotated by a predetermined angle, and the cutting blade is replaced by performing the opposite operation to the above. However, this severely limits the automation and labor saving of cutting work.

Therefore, a support device for a throw-away tip equipped with an automatic cutting blade exchange function was developed, for example, in U.S. Pat.
Proposed by No. 203605. This support device is provided with a reciprocating rod that rotatably supports the throwaway chip inside the holder, and a cam at the tip of the holder that engages with the tip and rotates the tip by a predetermined angle when the retractable rod moves forward. It is equipped with a swing-type clamp that presses the tip from above in conjunction with the rod, so that the operations of clamp angle removal, tip rotation, and re-clamping can be achieved with one reciprocating movement of the rod. .

However, since such a support device rotates the chip using the linear movement of the advancing and retracting rod, it is difficult to increase the rotation angle of the chip, and therefore, although it is suitable for changing the cutting edge of a square chip, It is not suitable for exchanging the cutting blade of a triangular chip that requires a large rotation angle, and it also has the disadvantage that if there is an obstacle in front of the holder, it will hinder the movement of the advancing and retracting rod.

In addition, Japanese Patent Application Laid-open No. 53-37988 discloses that when a head member that can move forward and backward moves forward, the tip rotatably supported on the mounting seat of the member is moved away from the rotation regulating wall surface to unclamp it, and A cutting blade changing device in which the periphery of the chip is brought into contact with a rotary indexing member arranged separately from the tool, and the chip is rotated for corner changing of the cutting blade by relative movement between the head member and the indexing member after this contact. However, this device also has the following disadvantages.

(a) Since the rotary indexing member is provided at a separate location from the tool, not only does the installation space increase, but a separate drive system is required to move the indexing member to a predetermined point when necessary.

(b) When changing the corner of the cutting edge, it is necessary to move the tool to the position of the indexing member each time, resulting in a loss of working time.

(c) Since the movement of the head member for tip rotation is performed in a straight line, when installing a triangular tip in the direction shown in the drawing of the same publication, for example, the tip rotation regulating surface is used to ensure a forward path for the tip. can be provided on only one side, and the holding stability of the chip becomes insufficient, which tends to cause a decrease in cutting accuracy and chip life.

(d) If there is an obstacle such as a workpiece in front of the tool, the forward movement of the head member will be hindered, so it is necessary to place the indexing member at a sufficient distance from the cutting point, and as mentioned in (b) The loss time becomes longer.

(c) Means for solving the problem The present invention was made in order to eliminate the above-mentioned inconvenience, and its feature is that the tip of the holder is provided with a movable seat plate that pivots around the rear support shaft. Using this seat plate, the chip, which is rotatably placed on a support seat with a clamp pin in front of the seat plate, is made to protrude to the side of the holder, and in the middle of this movement, the tip is placed on a backing plate located on the side of the holder. The process involves engaging the tip and rotating the tip through the angle necessary to change the corner of the cutting edge.

(d) Example Hereinafter, an example of the throw-away bite of the present invention will be explained based on the attached drawings.

As shown in FIGS. 1 to 3, the tip of the holder 1 has seat walls 2, 2' that press the two adjacent sides of the throwaway tip A, which is a regular polygon with a center hole (the figure is an equilateral triangle). Further, on one side of the holder, horizontal grooves 3, which are connected to each other at the rear, are formed.
4 are provided at different heights.

Also, in the groove 3, as shown in FIG.
A reciprocating member 7 that moves in the holder axis direction is provided. The movable seat plate 6 has a chip support seat 6b in which a clamp pin 6a that passes through the center hole of the chip A is erected at the front, a side surface 6c inclined in the width direction and a fourth
Tapered surface 6d inclined in the height direction as shown in the figure
This seat plate has a biasing means 8
is constantly pushed in the protruding direction by the

On the other hand, the reciprocating member 7 has axial guide grooves 3a, 3a (third
Slide guide 7 to be fitted in (see figure or figure 4)
a, 7a at the tip, surfaces 6c, 6d of the movable seat plate
, and urges the seat plate 6 when moving forward.
Slanted side surface 7 that presses downward and in a direction that resists
b and a lower surface 7c, and on the upper surface of this reciprocating member, in addition to a slide guide, when moving forward,
A cam surface 7d that allows a backing plate, which will be described later, to be inserted into the holder.
is formed.

That is, in the groove 4, as shown in FIG.
It is provided so that a force of 1 is constantly applied in the protrusion direction,
When the shaft 10a protruding from the lower surface of the backing plate is pushed by the cam surface 7d of the reciprocating member, the biasing means 11 is pushed in and the backing plate 10 is pushed back from the chain line position to the solid line position in the figure. In addition, code 1
2 is a screw for adjusting the stop position of the backing plate.

Next, the cutting blade exchanging operation of the cutting tool will be explained based on FIGS. 5 and 6.

First, when the reciprocating member 7 in the forward position is moved backward by a suitable push/pull means, the movable seat plate 6 is loosened and the seat plate 6 pushed by the biasing means 8 begins to rotate in the projecting direction. However, the turning movement is
Since the seat plate is in contact with the side surface 7c of the advancing/retracting member, the movement is performed gradually. On the other hand, when the cam surface 7d of the reciprocating member retreats slightly, the abutment plate 10 is disengaged from this surface, so it is pushed by the biasing means 11 and rotates, and its tip moves together with the seat plate. Chip A
The screw 12 reaches the predetermined position indicated by the chain line in FIG. 6 earlier than that, ie, the position where the movement of the screw 12 is restricted.

Thereafter, when the reciprocating member 7 moves further back, the tip of the movable seat plate protrudes to follow the backing plate, and in the middle of this movement, the tip on the seat plate engages with the tip of the waiting backing plate 10. After this engagement, the seat plate continues to rotate by a predetermined angle, so that the tip A is
It rotates counterclockwise by a predetermined angle (approximately 120 degrees in the case of the example cutting tool) using a as a fulcrum, so that the tips a ₁ , a ₂ , and a ₃ of the tip, which were in the solid line position in Fig. 6, are shown by the chain lines. It changes its position and stops, thus completing the movement of the retracting member when retracting.

Next, when the reciprocating member 7 is moved forward, the seat plate 6 first starts returning, and when the movement is almost completed, the cam surface 7d pushes the shaft 10a to return the backing plate 10. Also, when the advancing/retracting member continues to move forward,
Due to the engagement of the surfaces 6c, 7b, 6d, and 7c, the seat plate 6 is strongly pushed in the return direction and downward, and the force in the return direction is transmitted to the chip via the clamp pin 6a, so that the chip A is The two side surfaces are pressed against and clamped against the seat walls 2, 2' of the holder, and at the same time, the seat plate 6 is also fixed to the holder by a downward force. Therefore, the cutting blade replacement work is now complete.

Here, a reaction force acts on the reciprocating member 7 when the chip is clamped, but this force is received by the two slide guides 7a, so there is a concern that the member 7 may be pushed out of the holder or the clamping force may decrease. There isn't.

Further, in the illustrated holder, the cutting blade can be replaced by determining the abutment position of the backing plate so as to rotate the tip within a range of 90 to 150 degrees. That is, it is desirable to rotate the equilateral triangular chip by 120 degrees, but even if the rotation angle deviates somewhat from that angle, the posture of the chip can be correctly corrected by the seat walls 2 and 3.

Furthermore, if there is no hindrance to the cutting work, the backing plate 10
may be fixed at a predetermined position.

The present invention can also be applied to changing the cutting edge of regular polygonal chips other than triangular, as long as the shape of the seat wall and the shape of the support seat of the movable seat plate are changed.

(E) Effects As mentioned above, the throw-away cutting tool of the present invention can automatically exchange the cutting edge of the tip by just one reciprocation of the advancing and retracting member. Since it protrudes to the side, there is no problem even if there is an obstacle in front of the holder, and since a backing plate is provided on the holder, there is no need to move the holder to a specific location when changing the corner of the cutting blade. . Therefore, it is possible to replace the cutting blade at a position close to the workpiece to eliminate unnecessary movement of the holder that affects work efficiency, and to create a seat for controlling the rotation of the chip that does not interfere with the rotation of the chip support seat, even for triangular chips. Ensure cutting accuracy by securing two walls,
This makes it possible to increase the stability of holding the chip and reduce the tool space to extend the life of the chip, further increasing the contribution to cutting work.

Further, even when the backing plate is made movable, it can be driven by the same drive source as the chip as in the embodiment, so the drive system can be simplified. Furthermore, since the tip can be rotated by a large angle by ensuring a sufficient turning angle of the movable seat plate, it can be applied to all existing regular polygonal tips for changing cutting edges.

In addition, since the clamp part is not located on the rake face of the chip, excellent effects such as improved cutting and ejection performance can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an example of the holder of the present invention;
Fig. 2 is a side view, Fig. 3 is a front view, Fig. 4 is a sectional view taken along line X-X in Fig. 2, Fig. 5 is a sectional view taken along line Y-Y in Fig. FIG. 6 is a sectional view taken along the Z-Z line. 1...Holder, 2,2'...Seat wall, 3,4...
Groove, 5... Support shaft, 6... Moving seat plate, 6a... Clamp pin, 6c, 6d... Tapered surface, 7... Advance/retreat member, 7a... Slide guide, 7b, 7c...
Tapered surface, 7d...Cam surface, 8...Biasing means, 9
... Support shaft, 10 ... Backing plate, 11 ... Biasing means,
12...adjustment screw.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A holder with a seat wall forming pressure contact between two sides of a regular polygonal indexable tip with a center hole at the tip, and a tip with an upright clamp pin that passes through the center hole of the tip. A movable seat plate which has a support seat and projects the support seat to the side of the holder by pivoting around a rear support shaft, means for biasing the movable seat plate in the projecting direction, and a reciprocating member that presses the movable seat plate in two directions, ie, in a direction against the urging means and in a downward direction, by a tapered surface and fixes the movable seat plate to the holder; a movable or fixed abutment plate, and a throw-away tip on the movable seat plate that protrudes to the side of the holder as the advancing/retracting member moves back is placed at the tip of the abutment plate during the rotation of the movable seat plate. A throw-away cutting tool that is configured to be engaged on the rear side of the holder with respect to the clamp pin and rotate the tip by an angle necessary for corner changing the cutting blade. (2) The above-mentioned movable backing plate has a second biasing means that pivots and projects the tip toward the side of the holder about the rear support shaft, while the advancing/retracting member engages with the backing plate when moving forward. A throw-away tool according to claim (1) of the utility model registration, characterized in that the throw-away tool has a cam surface that allows the backing plate to be inserted into the holder.