JP2001062606A - Clamp mechanism of throwaway tip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the clamp mechanism of a throwaway tip in which the attachment/detachment of the throwaway tip is easy. SOLUTION: In this clamp mechanism, an insertion hole 22 (a first insertion hole) having the diameter expansion part 22b in which the diameter is gradually expanded toward the upper surface is formed on the throwaway tip 15 mounted on the tip installation seat 13 of a tool main body 11. A main body insertion hole 23 (a second insertion hole) in which a crank pin 25 is inserted is formed on the tip installation seat 13. A press projection 31 for pressing the diameter expansion part 22b of the insertion hole 22 of the throwaway tip 15 is formed on the head 25a of the crank pin 25 and the head 25a is formed so that the maximum width is smaller than the inner diameter of the insertion hole 22. A fixing screw 26 (fixing member) for pressing the crank pin 25 in the pull-in direction in the main body insertion hole 23 is arranged on the side of the crank pin 25.

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 mounted on a throw-away tool such as a small cutting tool for an automatic lathe.

[0002]

2. Description of the Related Art Conventionally, in a small-sized cutting tool used for a precision automatic lathe or the like, a plurality of kinds of cutting tools are arranged in a comb shape. In some cases, cutting is performed continuously. In such a small bite, a throw-away type bite is usually used, and the tip is replaced according to wear of the cutting blade. In this case, the insertable direction of a wrench or the like for attaching and detaching the throw-away tip is limited depending on the arrangement direction of the cutting tool. For this purpose, for example, a clamp of the throw-away tip as disclosed in Japanese Utility Model Laid-Open Publication No. A mechanism has been proposed.

In this clamp mechanism for a throw-away tip, as shown in an enlarged side sectional view of a main part of FIG. The mounting seat 3 is provided with, for example, a generally parallelogram plate-shaped throw-away chip 4 (hereinafter referred to as a chip). An anchor pin 5 is inserted into a hole 3a of the chip mounting seat 3 through a center hole 4a formed between the upper and lower surfaces of the chip 4.
Is fixed by being pressed by a fixing screw 6 screwed to the cutting tool main body 2 in a direction substantially orthogonal to this. Moreover, a thread-wound shaft-shaped concave engaging portion 7 is formed at an intermediate portion of the anchor pin 5, and the substantially dome-shaped head 8 of the fixing screw 6 is brought into contact with the engaging portion 7 to rotate. As a result, the anchor pin 5 is pulled downward by the rotational friction force. Simultaneously pressed, the anchor pin 5 is inclined in a direction in which the head 5a presses the chip 4 against the side wall 3b of the chip mounting seat 3. As a result, the chip 4 is pressed and fixed to the bottom surface 3c and the side wall 3b of the chip mounting seat 3.

[0004]

However, in such a clamp mechanism for a throw-away tip, when the tip 4 is to be removed, the anchor pin 5 must be removed, which makes the tip replacement work cumbersome.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a clamp mechanism for a throw-away tip in which the detachable tip can be easily attached and detached.

[0006]

According to a first aspect of the present invention, there is provided a clamp mechanism for a throw-away insert, comprising: a first insertion hole for a throw-away tip mounted on a tip mounting seat of a tool body; A clamp pin is inserted through a second insertion hole formed in the tip mounting seat, and the clamp pin is pulled into the second insertion hole by operating a fixing member, and the clamp pin pulls the throw-away tip. In the clamp mechanism of a throw-away tip pressed and fixed to a tip mounting seat, the first insertion hole of the throw-away tip is provided with an enlarged diameter portion from the tip mounting seat side to the other side; On the head of the pin, a pressing projection that presses the enlarged diameter portion of the first insertion hole provided in the throw-away tip projects to one side. Vignetting in, and the head of the clamp pin is characterized in that it is smaller than the inner diameter of the maximum width portion is also included that the pressing projection is formed the first insertion hole.

In the clamp mechanism of the throw-away tip configured as described above, the head of the clamp pin, including the pressing projection, is smaller in diameter than the inner diameter of the first insertion hole of the throw-away tip. By inserting and removing the head of the clamp pin into and out of the first insertion hole without removing the tool from the tool body, the detachable tip can be attached and detached. Then, by operating the fixing member with the throw-away tip attached, the clamp pin is drawn into the second insertion hole, and is formed in the first insertion hole of the throw-away tip by the pressing protrusion of the head of the clamp pin. The enlarged diameter portion is pressed downward and to one side, and the throw-away tip is fixed.

According to a second aspect of the present invention, there is provided a clamp mechanism for a throw-away tip, wherein an engaging hole to be engaged with the fixing member is formed on a side of the clamp pin. The fixing member is provided with an eccentric protrusion at a position eccentric with respect to its own rotation axis, and the eccentric protrusion rotates an inner wall surface of the engagement hole by rotating the fixing member. It is characterized by being engaged with the engagement hole so as to press. In the clamp mechanism of the throw-away tip configured as described above, by rotating the fixing member, the inner wall surface of the engaging hole of the clamp pin is pressed by the eccentric projection provided on the fixing member, and the clamp pin is rotated. Moved. By rotating the fixing member in this way, the clamp pin can be moved from the position where the throw-away tip is fixed to the position where the throw-away tip is attached / detached.

According to a third aspect of the present invention, the second insertion hole is inclined with respect to the bottom of the tip mounting seat. And the clamp pin is inserted into the second insertion hole with the pressing protrusion directed toward the inclined side of the second insertion hole. In the throw-away tip clamping mechanism configured as described above, since the moving direction of the clamp pin is inclined with respect to the bottom surface of the tip mounting seat, the second insertion hole is substantially perpendicular to the bottom surface of the tip mounting seat. The detachable tip can be easily attached and detached as compared with the case where the tip is provided.

According to a fourth aspect of the present invention, there is provided a clamp mechanism for a throw-away tip according to any one of the first to third aspects, wherein the clamp mechanism is provided between the second insertion hole and the clamp pin. A biasing means is provided for biasing the clamp pin in a direction to push the clamp pin out of the second insertion hole. In the clamp mechanism of the throw-away tip configured as described above, when the pressing of the clamp pin by the fixing member is released, the clamp pin is pressed by the urging member and moved toward the position where the throw-away tip is attached and detached. .

According to a fifth aspect of the present invention, there is provided a clamp mechanism for a throw away tip, wherein the clamp pin is fixed to the throw away tip when the throw away tip is fixed. The portion located in the two insertion holes is a large diameter portion having a diameter larger than the first insertion hole of the throw away tip, and a step portion is formed at a boundary between the large diameter portion and the head of the clamp pin. It is characterized by being formed. In the throw-away tip clamping mechanism configured as above, the throw-away tip is pressed by the step portion and lifted from the tip mounting seat with the projection of the clamp pin.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A throw-away tool to which a clamp structure of a throw-away tip according to an embodiment of the present invention will be described below with reference to FIGS.
FIG. 1 is a partially cutaway plan view and a partially cutaway side view of the indexable cutting tool 10, FIG. 2 is an enlarged perspective view illustrating the shape of a clamp pin and a fixing screw and their engagement relationship, and FIG.
FIG. 4 is an enlarged side sectional view of a main part showing a chip attaching / detaching operation in the indexable cutting tool 10. Here, FIG.
FIG. 3 shows a cross section orthogonal to the axis of the fixing screw 26 (described later). Indexable cutting tool 1 shown in FIG.
In FIG. 1, the tool main body 11 has, for example, a substantially quadrangular prism shape, the tip of which is obliquely cut, and a substantially parallelogram is formed at the corner of the tip of one surface (this is the upper surface) 12 a shown in FIG. A plate-shaped concave portion is formed, and the chip mounting seat 13 is formed. The tip mounting seat 13 is formed of a substantially parallelogram-shaped bottom surface 13a (see FIG. 1B) and two side walls 13b and 13c that intersect each other at an acute angle. Further, a slack portion 14 is formed at the intersection of the two side walls 13b and 13c, and the bottom surface 13a is a plane extending to the slack portion 14.

The chip mounting seat 13 has a substantially parallelogram plate-like throw-away chip 15 (hereinafter referred to as a chip).
Is attached. As shown in FIG. 1B, the chip 15 has an upper surface 17 formed opposite to a lower surface 16 forming a seating surface, and a side surface 18 includes, for example, a positive chip that is gradually inclined outward from the lower surface 16 to the upper surface 17. (A negative chip may be used). As shown in FIG. 1 (a), a front cutting edge 20 </ b> A and a horizontal cutting edge 20 </ b> B protruding from the tool body 11 are provided on the ridge of the upper surface 17 of the tip 15. The chip 15 has upper and lower surfaces 1 as shown in FIG.
Insertion hole 22 (first insertion hole) penetrating through the center of 7 and 16
The insertion hole 22 is formed by a straight hole portion 22a having the same inner diameter and an enlarged diameter portion 22b gradually tapered from the upper end of the straight hole portion 22a toward the upper surface 17. . The insertion hole 22 preferably has a horizontal cross section of a perfect circle or a shape close to a perfect circle. Also, the enlarged diameter portion 22b
As long as the diameter is continuously increased, it may have a curved surface shape, for example, a bell hole shape having a substantially bell shape in a side sectional view, instead of the tapered surface shape.

As shown in FIG. 1B, the tool body 11 is provided with a clamp pin 25 at the center of the bottom surface 13a of the chip mounting seat 13 so as to be substantially coaxial with the insertion hole 22 of the mounted chip 15. Body insertion hole 23 into which (described later) is inserted
(Second insertion hole) is formed. Then, FIG.
As shown in the figure, two side surfaces 12b and 12
For example, a screw hole 24 that extends in a direction substantially perpendicular to the main body insertion hole 23 and communicates with the main body insertion hole 23 is formed on one side surface 12 b of the c that is separated from the chip mounting seat 13,
A fixing screw 26 (fixing member) is screwed into the screw hole 24. Further, the bottom surface of the main body insertion hole 23 is
As shown in (b), a substantially circular body-side recess 27 is formed concentrically with the body insertion hole 23, and a coil spring 28 (biasing member) is inserted into the body-side recess 27 at a lower end thereof and positioned. It is installed in the state where it was done. The coil spring 28 is provided between the bottom of the clamp pin 25 and the main body insertion hole 2.
3, and biases the clamp pin 25 in a direction to push it out of the main body insertion hole 23.

As shown in FIG. 2, the fixing screw 26 has, for example, a substantially columnar shape without a head, and has a thread cut on the outer peripheral surface thereof. The fixing screw 26 has a main body insertion hole 23 side (a front side in FIG. 2). ) Is provided on the end face facing eccentrically with respect to its own rotation axis O and in parallel with the axis.
a is formed. As shown in FIG. 1A, the eccentric protruding portion 26 a is rotated by operating the fixing screw 26 in a state of protruding into the main body insertion hole 23, so that the engaging pin 32 (described later) is pressed to move the clamp pin 25 in the axial direction of the main body insertion hole 23.

As shown in FIG. 1B, the clamp pin 25 is housed in the main body insertion hole 23 of the tool main body 11 with the head 25a protruding from the bottom surface 13a of the chip mounting seat 13. A pressing projection 31 for pressing the chip 15 toward the chip mounting seat 13 is provided on the head 25a.
Are formed to protrude to one side. Here, the head 25 a has a maximum width including the pressing protrusion 31 smaller than the inner diameter of the insertion hole 22 formed in the chip 15. The clamp pin 25 has a large-diameter portion 25b whose diameter is larger than the insertion hole 22 of the chip 15 when the chip 15 is fixed. Step 25 at the boundary with section 25a
c is formed. As shown in FIG. 3, a substantially circular engagement hole 32 is provided on the side of the large diameter portion 25 b so that the axis is substantially perpendicular to the axis of the clamp pin 25. Here, the engagement hole 32 is formed so that the engagement protrusion 31 is formed in the tool body 1.
The fixing screw 26 is formed so as to be engaged with the eccentric protruding portion 26 a of the fixing screw 26 in a state facing the one squatting portion 14. Further, the coil spring 28 is provided on the bottom of the clamp pin 25.
Is formed with a pin-side concave portion 33 with which the other end is engaged.

The indexable cutting tool 10 according to the present embodiment has the above-described configuration, and includes a tool body 11.
When the chip 15 is mounted on the device, the fixing screw 26 is operated so that the eccentric protrusion 26a is positioned upward, and the pressing of the engaging hole 32 of the clamp pin 25 by the eccentric protrusion 26a is released. Then, the clamp pin 25 is pushed out from the main body insertion hole 23 by the urging force of the coil spring 28, and a space is secured between the clamp pin 25 and the chip mounting seat 13 so that the chip 15 can be attached and detached.
It protrudes from the chip mounting seat 13. In this state, the chip 15 is placed on the chip mounting seat 13 while the head 25a of the clamp pin 25 is inserted through the insertion hole 22 of the chip 15 (see FIG. 3A). Next, the fixing screw 26 is connected to the eccentric projection 2.
6a, the inner wall surface of the engagement hole 32 is pressed downward by the eccentric protrusion 26a, thereby reducing the urging force of the coil spring 28 as shown in FIG. Then, the clamp pin 25 is pulled into the main body insertion hole 23. Thereby, the head 2 of the clamp pin 25
The pressing projection 31 provided on the tip 5 a pushes the enlarged diameter portion 22 b formed in the insertion hole 22 of the chip 15 downward and on one side, that is, the bottom surface 13 a and the side wall 13 b of the chip mounting seat 13.
The slack portion 14 which is an intersection of 3c (not shown in FIG. 3)
Is pressed toward the chip mounting seat 13.
Is pressed and fixed.

When removing the tip 15 from the tool body 11, the fixing screw 26 is operated so that the eccentric projection 26a is located upward, and the pressing of the engaging hole 32 of the clamp pin 25 by the eccentric projection 26a is performed. The clamp pin 25 is released from the chip mounting seat 13 by the urging force of the coil spring 28 to such an extent that a space for mounting and dismounting the chip 15 is secured between the clamp pin 25 and the chip mounting seat 13 (FIG. 3). (A)). At this time, since the chip 15 is pressed by the step 25 c of the clamp pin 25, the chip 15 is lifted from the chip mounting seat 13 with the protrusion of the clamp pin 25.

According to the clamp structure of the indexable insert configured as described above, it is not necessary to remove the clamp pin 25 from the tool main body 11 at the time of the operation of attaching and detaching the insert 15, so that the insert 15 can be easily attached and detached. In addition, since a work space for removing the clamp pin 25 can be omitted, the space between the indexable cutting tools 10 can be reduced to save space. Then, the chip 15 can be fixed and released by the clamp pin 25 only by rotating the fixing screw 26 about half a turn. Further, when the pressing of the clamp pin 25 by the fixing screw 26 is released, the clamp pin 25 is automatically protruded from the main body insertion hole 23, and the tip 15 is accordingly attached to the tip mounting seat 1.
Since the chip 15 is lifted from the position 3, the chip 15 can be easily removed.

In the above embodiment, the main body insertion hole 2
3 is formed substantially perpendicular to the bottom surface 13a of the chip mounting seat 13, but is not limited thereto.
As shown in an enlarged side sectional view of a main part of FIG.
The tip mounting seat 13 is provided to be inclined with respect to the bottom surface 13a,
The clamp pin 25 may be inserted into the main body insertion hole 23 with the pressing protrusion 31 facing the inclined side of the main body insertion hole 23. Here, FIG. 4 shows a cross section orthogonal to the axis of the fixing screw 26. In the case of such a configuration, compared with the case where the main body insertion hole 23 is provided substantially perpendicular to the bottom surface 13 a of the chip mounting seat 13, between the pressing projection 31 and the clamp pin 25 for replacement of the chip 15. When securing a space where the chip 15 can be attached and detached, the amount by which the clamp pin 25 projects from the bottom surface 13a of the chip mounting seat 13 is reduced, and the interval between the indexable cutting tools 11 is further reduced to save the space. Space can be achieved. In addition, as compared with the case where the main body insertion hole 23 is provided substantially perpendicular to the bottom surface 13 a of the chip mounting seat 13, the main body insertion hole 23 is formed between the side surface of the chip 15 and the side wall of the chip mounting seat 13 when the chip 15 is attached and detached. Since the distance is large, detachment can be facilitated even when the chip 15 is a negative chip.

In the above embodiment, the fixing screw 26 having the eccentric projection 26a engaged with the engaging hole 32 of the clamp pin 25 is used as a fixing member, and the eccentric projection 26a is rotated by rotating the fixing screw 26. By pressing the inner wall surface of the engagement hole 32 of the clamp pin 25 with the
Is drawn into the main body insertion hole 23.
However, the present invention is not limited to this, and may be configured as shown in an enlarged side sectional view of a main part in FIG. That is, instead of the fixing screw 26, a fixing screw 34 having a tapered tapered portion 34 a formed at the end of the body insertion hole 23 on the inner wall surface of the engaging hole 32 of the clamp pin 25 is used. A tapered portion 35 whose diameter is increased toward the fixing screw 34 is formed at an end of the fitting hole 32 on the fixing screw 34 side. By operating the fixing screw 34 to advance into the engaging hole 32, the tapered portion 34a of the fixing screw 34 presses the tapered portion 35 of the engaging hole 32 downward,
The clamp pin 25 is pulled into the main body insertion hole 23. Here, FIG. 5 shows a cross section parallel to the axis of the fixing screw 34.

[0022]

According to the clamp mechanism of the indexable insert according to the first aspect, it is not necessary to remove the clamp pin from the tool body at the time of the indexable insert attachment / detachment operation. Further, the space between the tools can be shortened to save the pace.

According to the clamp mechanism of the throw-away tip according to the second aspect, the rotation of the clamp pin makes it possible to easily press and release the push of the throw-away tip by the clamp pin.

According to the third aspect of the present invention, the throw away tip can be easily attached and detached.

According to the clamp mechanism of the throw-away tip, the fixing of the throw-away tip by the clamp pin is automatically performed, so that the detachable tip can be easily attached and detached.

According to the clamp mechanism of the throw-away tip, when the throw-away tip is replaced, the throw-away tip is lifted from the tip mounting seat along with the protrusion of the clamp pin. Removal can be performed more easily.

[Brief description of the drawings]

FIG. 1 is a view showing a throw-away tool having a clamp structure of a throw-away tip according to an embodiment of the present invention, wherein (a) is a partially broken plan view, and (b) is a partially broken side view. is there.

FIG. 2 is an enlarged perspective view illustrating shapes of a clamp pin and a fixing screw of a throw-away tool according to the embodiment of the present invention, and an engagement relationship between them.

FIG. 3 is an enlarged side cross-sectional view of a main part, showing an operation of attaching and detaching the throw-away tip in the throw-away tool according to the embodiment of the present invention.

FIG. 4 is an enlarged side sectional view showing a configuration and a structure of a throw-away tool to which a clamp structure of a throw-away tip according to another embodiment of the present invention is applied.

FIG. 5 is an enlarged side sectional view showing a configuration and a structure of a throw-away tool to which a clamp structure of a throw-away tip according to another embodiment of the present invention is applied.

FIG. 6 is an enlarged side sectional view of a main part of a cutting tool showing a configuration and a structure of a conventional throw-away tip clamping mechanism.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 Tool main body 13 Tip mounting seat 15 Throw-away tip 22 Insertion hole (first insertion hole) 22b Large diameter portion 23 Main body insertion hole (second insertion hole) 25 Clamp pin 25a Head 26 Fixing screw (fixing member) 26a Eccentric projection Part 28 coil spring (biasing means) 31 pressing protrusion 32 engagement hole

Claims (5)

[Claims] A clamp member is inserted into a first insertion hole of a throw-away tip mounted on a tip mounting seat of a tool body and a second insertion hole formed in the tip mounting seat to operate a fixing member. In the clamp mechanism of the throw-away tip, wherein the clamp pin is pulled into the second insertion hole and the clamp pin presses and fixes the throw-away tip to the tip mounting seat, The insertion hole is provided with an enlarged diameter portion from the tip mounting seat side to the other side, and presses the enlarged diameter portion of the first insertion hole provided in the indexable tip against the head of the clamp pin. A pressing protrusion is provided so as to protrude to one side, and the head of the clamp pin has a maximum width including a portion where the pressing protrusion is formed in the first insertion hole. Clamping mechanism indexable insert, characterized in that it is smaller than the inner diameter. 2. An engaging hole to be engaged with the fixing member is provided on a side of the clamp pin, and the fixing member has an eccentric protrusion at a position eccentric with respect to its own rotation axis. The throwaway according to claim 1, wherein the eccentric protrusion is engaged with the engagement hole so as to press an inner wall surface of the engagement hole by rotating the fixing member. Tip clamping mechanism. 3. The state in which the second insertion hole is provided to be inclined with respect to the bottom surface of the tip mounting seat, and the clamp pin faces the pressing protrusion toward the inclined side of the second insertion hole. The clamp mechanism for a throw-away tip according to claim 1 or 2, wherein the clamp mechanism is inserted into the second insertion hole. 4. An urging means is provided between said second insertion hole and said clamp pin to urge said clamp pin in a direction to push said clamp pin out of said second insertion hole. 4. The clamp mechanism for a throw-away tip according to any one of 1 to 3. 5. A portion of the clamp pin located in the second insertion hole when fixing the throw-away tip is a large-diameter portion having a larger diameter than the first insertion hole of the throw-away tip. 5. The clamp mechanism for a throw-away tip according to claim 1, wherein a step portion is formed at a boundary between the large diameter portion and the head of the clamp pin.