JP2007203437A - Clamp mechanism for cutting insert, insert attachment and detachment type cutting tool, and cutting insert - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a clamp mechanism for a cutting insert, which seats the cutting insert stably and fixes the cutting insert firmly. <P>SOLUTION: This clamp mechanism for the cutting insert 40 clamps the cutting insert 40 by inserting and nipping it into an insert mounting seat 34 provided with a pressing face 28 and a pedestal face 20 extending by opposing mutually. A fitting part 22 is formed in a central part in the direction of width of the pedestal face 20, a part 47 to be fitted into the fitting part 22 is formed in a central part in the direction of width of a bottom face 40A of the cutting insert 40, either of the fitting part 22 and the part 47 to be fitted is formed into a projecting V shape, the other and is formed into a recessed V shape, plane parts 21 are formed in both end parts in the direction of width of the pedestal face 20, and abutting faces 46 abutted on the plane parts 21 are formed in both end parts in the direction of width of the bottom face 40A of the cutting insert 40. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention includes, for example, an insert detachable cutting tool used for grooving or parting off a workpiece, and includes a cutting insert clamping mechanism for detachably attaching a cutting insert to an insert mounting seat of a holder and the clamping mechanism. The present invention relates to an insert detachable cutting tool and a cutting insert attached to the clamp mechanism.

The clamping mechanism of the cutting insert provided in the insert detachable cutting tool used for such grooving or parting off has a pressing surface and a pedestal surface that extend toward the tip of the holder and are arranged to face each other. It is known that a cutting insert is inserted into an insert mounting seat, and the cutting insert is clamped by bringing the pressing surface and the pedestal surface close to each other (see, for example, Patent Document 1).
One of the pedestal surface and the bottom surface of the cutting insert arranged so as to contact each other is formed in a concave V shape, and the other is formed in a convex V shape, and the pedestal surface and the bottom surface are so-called V-shaped. It is comprised so that a character may be fitted.

An insert detachable tool having such a clamp mechanism rotates at a high speed after being clamped and fixed to an insert mounting seat formed at the tip of the holder and supported by a machine tool such as a lathe or a machining center. The outer surface and the end surface of the workpiece are cut by the cutting blade of the cutting insert by being moved relative to the workpiece in a state where the cutting insert is pressed against the workpiece.
JP 2001-62608 A

However, in the above clamping mechanism, since one of the bottom surface of the cutting insert and the pedestal surface of the holder has a convex V shape and the other has a concave V shape, the shape of the bottom surface and the shape of the pedestal surface If they do not coincide with each other accurately, the position of the cutting insert may be inclined without being stable when the cutting insert is seated on the pedestal surface.
Moreover, when the position where the cutting insert is pressed by the pressing surface is deviated from the center in the width direction of the cutting insert, the cutting insert easily moves along the inclined surface having a concave V shape or a convex V shape, There was a possibility that the position of the cutting insert was not stable.

In particular, on the tip end side of the holder, the cutting insert may be inclined or the position may be displaced due to the main component force of the cutting resistance acting on the cutting edge. Furthermore, even when the insert detachable cutting tool is moved relative to the workpiece in the width direction of the cutting insert, the cutting insert may move due to the feed force of the cutting resistance acting on the cutting edge. was there.
When cutting is performed with the position of the cutting insert being unstable in this way, the cutting angle and clearance angle of the cutting edge will be distorted, the processing accuracy will deteriorate, and an excessive load will be applied to the cutting insert. There was a problem that the cutting insert was damaged.

  The present invention has been made in view of such a situation, and is capable of stably seating a cutting insert and firmly clamping the cutting insert, and the clamping mechanism. It is an object to provide an insert detachable cutting tool and a cutting insert.

  In order to solve this problem, the present invention clamps by inserting and inserting a cutting insert into an insert mounting seat formed at the tip of the holder and extending opposite to each other and having a pressing surface and a pedestal surface. A clamping mechanism for a cutting insert, wherein a fitting portion is formed at a center portion in the width direction of the pedestal surface, and is fitted to the fitting portion at a center portion in the width direction of the bottom surface of the cutting insert. A portion is formed, and one of the fitting portion and the fitted portion is configured in a convex V shape, and the other is configured in a concave V shape, and flat portions are provided at both ends in the width direction of the pedestal surface. In addition to being formed, contact surfaces that are in contact with the flat surface portion are formed at both ends in the width direction of the bottom surface of the cutting insert.

Moreover, the insert detachable cutting tool of the present invention is characterized by including the above-described clamping mechanism.
Furthermore, the cutting insert of the present invention is a cutting insert attached to the above-described clamping mechanism, and a fitted portion configured in a convex V shape or a concave V shape is formed in the center portion in the width direction of the bottom surface. It is formed and the contact surface comprised in the planar shape is formed in the width direction both ends of the said bottom face, It is characterized by the above-mentioned.

  According to the clamping mechanism of the cutting insert, the insert detachable cutting tool, and the cutting insert according to the present invention, the flat portion is formed at both widthwise ends of the pedestal surface, and the flat portion is formed at both widthwise ends of the cutting insert. Since the contact surface to be contacted is formed, when the cutting insert is seated on the pedestal surface, the flat portion and the contact surface come into contact with each other, and the seating position of the cutting insert is stabilized.

Furthermore, a fitting part is formed in the center part in the width direction of the pedestal surface, and a fitted part to be fitted to the fitting part is formed in the center part in the width direction of the bottom surface of the cutting insert. Since one of the fitted portions is formed in a convex V shape and the other is formed in a concave V shape and is fitted to each other, the width direction position of the cutting insert and the pedestal portion is fixed, and the width of the cutting insert Even if the workpiece is relatively moved in the direction and cut into the workpiece, the position of the cutting insert is stabilized, and high-precision machining can be performed.
In addition, since the fitting portion and the fitted portion are V-fitted by pressing the cutting insert onto the pedestal portion with the pressing surface, the cutting insert can be strengthened by clamping between the pressing surface and the pedestal portion. Can be fixed.

  Here, by forming the fitting portion and the flat portion so as to reach the tip of the pedestal surface, the main component force of the cutting resistance acting on the cutting blade of the cutting insert disposed on the tip side of the pedestal surface Can be received by the plane portion arranged substantially perpendicular to the main component force, and the rigidity against the cutting resistance can be improved and the inclination of the cutting insert can be prevented.

  Therefore, according to the present invention, it is possible to provide a cutting insert clamping mechanism, an insert detachable cutting tool and a cutting insert capable of stably seating the cutting insert and firmly fixing the cutting insert. it can.

A first embodiment of the present invention will be described with reference to the accompanying drawings. 1 to 3 show an insert detachable tool to which the clamp mechanism according to the first embodiment is applied, FIG. 4 shows a pedestal surface formed on a holder, and FIGS. 5 and 6 show a cutting insert.
The insert detachable tool includes a holder 10 and a cutting insert 40 that is detachably attached to the holder 10.

As shown in FIGS. 1 and 2, the holder 10 has a flat shelf 11 that protrudes slightly above the upper surface 10A of the holder 10 and extends parallel to the upper surface 10A. At the front end side of the shelf portion 11, the holder 10 extends in parallel with the upper surface 10 </ b> A from the position lower than the shelf portion 11 and the upper surface 10 </ b> A toward the front end side (left side in FIG. 2) of the holder 10. A pedestal 12 that extends flush with one side surface 10B is formed.
The connecting portion of the shelf portion 11 and the pedestal portion 12 is an inclined wall 13 that gradually recedes downward as it goes toward the tip of the holder 10, and at the intersection of the inclined wall 13 and the pedestal portion 12, A notch 14 is formed.

  In addition, a concave portion 15 that is recessed downward and a protruding portion 16 that is located on the rear end side of the holder 10 of the concave portion 15 and protrudes greatly upward are formed on the rear end portion of the shelf portion 11 of the holder 10. ing. An engaging groove 17 having a quadrangular cross section extending in parallel with the pedestal portion 12 is formed on the opposite side of the one side surface 10B of the holder 10 across the shelf portion 11.

A surface facing upward of the pedestal portion 12 is a pedestal surface 20, and the pedestal surface 20 has a flat portion 21 whose both end portions in the width direction extend parallel to the upper surface 10 </ b> A of the holder 10, as shown in FIGS. In addition, the central portion in the width direction sandwiched between the flat portions 21 is the fitting portion 22.
The fitting portion 22 is formed in a concave V shape by a pair of inclined surfaces 23, 23 that approach each other as it goes downward, and the plane that bisects the concave V shape is orthogonal to the plane formed by the plane portion 21. It has been made. Further, the intersecting ridge line where the pair of slopes 23, 23 intersect is arranged so as to coincide with the center line in the width direction of the pedestal surface 20.
The flat portion 21 and the fitting portion 22 are formed so as to reach the tip of the pedestal surface 20 over the entire length in the longitudinal direction of the pedestal surface 20.

A clamp piece 25 is disposed above the pedestal 12 and the shelf 11. As shown in FIG. 1, the clamp piece 25 includes a piece main body 26 having a rectangular block shape and a pressing portion 27 extending from the piece main body 26 so as to face the pedestal portion 12.
As shown in FIG. 2, the pressing portion 27 is inclined so as to gradually approach the pedestal surface 20 as it goes toward the front end side of the holder 10. A pressing surface 28 is formed.
Further, the clamp piece 25 has a U-shape as shown in FIG. 3 when viewed from the front, and is formed with an engagement convex portion 29 protruding downward from the piece main body 26, and this engagement convex portion. 29 is engaged with the engaging groove 17.

  Further, a fulcrum portion 30 protruding in a semi-cylindrical shape toward the lower side is provided at the rear end portion of the piece main body 26, and this fulcrum portion 30 is formed on the tip end side of the holder 10 of the protruding portion 16. It is accommodated in the recess 15. Further, the upper surface of the piece main body 26 is inclined so as to gradually recede downward as it goes toward the rear end side of the holder 10.

In the clamp piece 25, a clamp screw 31 formed in the shelf 11 is inserted into a screw insertion hole (not shown) that opens to the upper surface of the piece body 26 and penetrates to the lower surface of the piece body 26. It is attached to the holder 10 by being screwed onto the holder 10 (not shown).
The clamp screw 31 has a screw portion 32 and a head 33 having a larger diameter than the screw portion 32, and the screw portion 32 is arranged so as to be orthogonal to the shelf portion 11. As a result, the upper surface of the inclined piece body 26 and the portion of the lower surface of the head 33 of the clamp screw 31 which are arranged on the tip side of the holder 10 come into contact with each other. The front end side portion of the clamp piece 25 is configured to move downward with 30 as a fulcrum.
The pedestal surface 20 and the pressing surface 28 formed on the clamp piece 25 constitute an insert mounting seat 34.

  The cutting insert 40 attached to the insert mounting seat 34 thus configured is made of a hard material such as cemented carbide, and as shown in FIG. 5, the insert body 41 whose outer shape is formed in a substantially square bar shape. And the cutting blade portions 42 disposed at both ends of the insert main body 41 and are integrally formed. That is, the cutting insert 40 is a dog bone-shaped insert formed so as to be symmetric with respect to the longitudinal center line.

The cutting blade portion 42 is formed with cutting blades 43 extending in the direction orthogonal to the longitudinal direction of the insert body 41 at the upper end portion thereof, and is connected to these cutting blades 43 in one end portion and the other end portion in the longitudinal direction. The surface facing the end portion is a flank surface 44 of the cutting blade 43, and is inclined so as to approach the center portion side in the longitudinal direction of the insert body 41 as it goes to the lower side of the cutting insert 40 as shown in FIG. The positive clearance angle is given. Moreover, the upper surface of the cutting edge part 42 used as the rake face 45 of the cutting edge 43 is formed in the concave curved surface shape dented toward the lower side, and the rake angle of the cutting edge 43 is made positive.
The insert body 41 has a constant width in its longitudinal direction, and its upper surface is formed in a planar shape parallel to the direction in which the cutting edge 43 extends and the longitudinal direction of the cutting insert 40.

At both ends in the width direction of the bottom surface 40 </ b> A of the cutting insert 40, a flat contact surface 46 extending in parallel with the top surface of the insert body 41 is formed, and the width of the bottom surface 40 </ b> A sandwiched between the contact surfaces 46 is formed. A fitted portion 47 is formed at the center in the direction.
As shown in FIG. 6, the fitted portion 47 has a convex V shape that protrudes downward by a pair of inclined surfaces 48 and 48 that approach each other toward the inner side in the width direction of the insert body 41 as it goes downward. The plane that bisects the convex V-shape is perpendicular to the plane formed by the contact surface 46. The angle at which the pair of inclined surfaces 48 and 48 intersect is equal to the angle of intersection between the pair of inclined surfaces 24 and 24 forming the fitting portion 22 of the pedestal surface 20, and the pair of inclined surfaces 48. , 48 is formed with a flat surface 49 extending in parallel with the contact surface 46.
The contact surface 46 and the fitted portion 47 are formed over the entire length in the longitudinal direction of the bottom surface 40 </ b> A of the cutting insert 40.

The cutting insert 40 is attached to the insert mounting seat 34 as follows to constitute an insert detachable cutting tool.
First, the cutting insert 40 is seated on the pedestal surface 20. At this time, the abutting surface 46 of the cutting insert 40 is disposed so as to abut against the flat portion 21 of the pedestal surface 20 and forms a concave V shape with the fitted portion 47 of the convex V-shaped cutting insert 40. It arrange | positions so that the fitting part 22 of the base surface 20 may fit.

  In this state, by screwing the clamp screw 31, the tip side portion of the clamp piece 25 moves so as to bend downward, and the pressing portion 27 having the pressing surface 28 facing the pedestal surface 20 approaches the pedestal surface 20. The pressing surface 28 is brought into contact with the upper surface of the insert body 41. When the clamp screw 31 is further screwed in, the pressing portion 27 presses the cutting insert 40 downward, so that the fitted portion 47 and the fitting portion 22 are V-shaped, and the cutting insert 40 abuts. The surface 46 is in close contact with the flat portion 21 of the pedestal surface 20, and the cutting insert 40 is sandwiched between the pedestal surface 20 and the pressing surface 28.

  The insert detachable cutting tool configured as described above is supported by a machine tool such as a lathe or a machining center, and is moved relative to the workpiece while the cutting insert 40 is pressed against the workpiece rotating at high speed. As a result, the outer surface and end surface of the workpiece are cut by the cutting blade 43 of the cutting insert 40. In this cutting process, a cutting material 43 is cut from the upper surface side of the cutting edge 43 which becomes the rake face 45 of the cutting edge 43, and the main component acts on the cutting edge 43 vertically downward.

In the clamping mechanism of the cutting insert 40 having such a configuration, the flat abutting surface 46 formed on the bottom surface 40A of the cutting insert 40 has the flat surface portion 21 of the pedestal surface 20 that is also formed in a flat shape. Therefore, the seating position when the cutting insert 40 is seated on the pedestal surface 20 is stabilized.
Further, the main component force of the cutting resistance that acts on the cutting blade portion 42 when the cutting operation is performed by the cutting blade 43 is received by the flat surface portion 21 that is arranged so as to be substantially orthogonal to the main component force. As a result, the rigidity against the cutting resistance is increased, the breakage of the cutting insert 40 can be prevented, and the cutting insert 40 can be prevented from being inclined or displaced.

  Further, a fitting portion 47 having a convex V shape is provided at the center portion in the width direction of the bottom surface 40 </ b> A of the cutting insert 40, and a fitting portion 22 having a concave V shape is provided at the center portion in the width direction of the pedestal surface 20. Since these are V-fitted, the relative position in the width direction between the cutting insert 40 and the pedestal surface 20 is fixed, and the position in the width direction of the cutting blade 43 can be fixed with high accuracy. Precision machining can be performed. In addition, the concave V-shaped bisector formed by the main body receiving portion 22 of the pedestal surface 20 and the convex V-shaped bisector formed by the bottom surface 41A of the insert main body 41 can be made to coincide with each other. And the pressing surface 28, the cutting insert 40 can be firmly fixed.

  Further, the fitted portion 47 is formed over the entire length in the longitudinal direction of the cutting insert 40, and the fitting portion 22 is also formed so as to reach the tip of the pedestal surface 20 over the entire length in the longitudinal direction of the pedestal surface 20. The cutting force feed component force acting when the insert detachable cutting tool is moved relative to the workpiece in the width direction of the cutting insert 40 is applied to the inclined surface 23 of the fitting portion 22 and the fitted portion 47. It can receive by fitting with the inclined surface 48, and the position shift of the cutting insert 40 in the width direction can be prevented. Further, the cutting insert 40 can be attached and detached without greatly moving the pressing portion 27 of the clamp piece 25 upward.

Next, a second embodiment of the present invention will be described. FIG. 7 shows an insert detachable tool to which the clamp mechanism according to the second embodiment is applied, FIG. 8 shows a pedestal surface, and FIGS. 9 and 10 show a cutting insert. In addition, the same code | symbol is attached | subjected to the part which is common in 1st Embodiment mentioned above, and description is abbreviate | omitted.
In the second embodiment, a pedestal portion 12 having a pedestal surface 20 is formed on the front end side of the holder 10 as in the first embodiment described above, and a planar shape is formed at both ends in the width direction of the pedestal surface 20. Is formed, and a fitting portion 22 is formed at the center in the width direction of the pedestal portion 20, and the shape of the fitting portion 22 is different from that of the first embodiment.

  As shown in FIG. 8, the fitting portion 22 is formed in a convex V-shape that protrudes upward by a pair of inclined surfaces 23 and 23 that approach each other toward the inner side in the width direction of the pedestal portion 20 as it goes upward. Has been. A flat surface 35 extending in parallel with the plane portion 21 is formed at the intersection of the pair of inclined surfaces 23, 23.

  The cutting insert 40 seated on the pedestal surface 20 configured in this way is made of a hard material such as cemented carbide, as in the first embodiment, and the outer shape is substantially as shown in FIG. The insert body 41 is formed in one piece with an insert body 41 formed in a square bar shape and cutting edge portions 42 disposed at both ends of the insert body 41. That is, the cutting insert 40 is a dog bone-shaped insert formed so as to be symmetric with respect to the longitudinal center line.

At both ends in the width direction of the bottom surface 40 </ b> A of the cutting insert 40, flat contact surfaces 46 extending in parallel with the top surface of the insert body 41 are formed, and at the center in the width direction sandwiched between the contact surfaces 46. A fitted portion 47 is formed.
As shown in FIG. 10, the fitted portion 47 has a concave V-shape that is recessed downward by a pair of inclined surfaces 48 and 48 that approach each other toward the inner side in the width direction of the insert body 41 as it goes upward. Is formed.
The contact surface 46 and the fitted portion 47 are formed over the entire length in the longitudinal direction of the bottom surface 40 </ b> A of the cutting insert 40.

  The cutting insert 40 is seated on the pedestal surface 20 and arranged so that the abutment surface 46 of the cutting insert 40 abuts against the flat portion 21 of the pedestal surface 20, and the cutting insert 40 having a concave V shape is formed. It arrange | positions so that the to-be-fitted part 47 and the fitting part 22 of the base surface 20 which makes a convex V shape may fit.

  When the clamp screw 31 is screwed in this state, the tip side portion of the clamp piece 25 moves so as to bend downward, and the pressing portion 27 having the pressing surface 28 facing the pedestal surface 20 comes close to the pedestal surface 20 and is pressed. The surface 28 is brought into contact with the upper surface of the insert body 41. When the clamp screw 31 is further screwed in, the pressing portion 27 presses the cutting insert 40 downward, the fitted portion 47 and the fitting portion 22 are V-fitted, and the contact surface 46 is the base surface 20. The cutting insert 40 is sandwiched between the pedestal surface 20 and the pressing surface 28 in close contact with the flat portion 21.

  In the clamping mechanism of the cutting insert 40 configured as described above, the cutting insert 40 can be stably seated on the pedestal surface 20 as in the first embodiment, and the cutting insert 40 can be firmly fixed. Can do.

The insert detachable cutting tool according to the embodiment of the present invention has been described above, but the present invention is not limited to this, and can be appropriately changed without departing from the technical idea of the present invention.
For example, although the cutting insert has been described as a dock bone type, it may be a single-edged insert in which a cutting edge portion is formed only at one end of the cutting insert.

  Moreover, although demonstrated as what clamps a cutting insert using a clamp piece, it is not limited to this, A pair of jaw part is formed by providing a slit in the front end side of a holder, One jaw part The pedestal portion and the other jaw portion as the pressing portion may be configured to be elastically deformable.

It is an expansion perspective view of the insert mounting seat periphery of the insert detachable cutting tool to which the clamping mechanism of the cutting insert which is the first embodiment of the present invention is applied. FIG. 1 is a side view around the insert mounting seat. It is a front view of the insert mounting seat periphery shown in FIG. It is a fragmentary perspective view which shows the base surface of the insert attachment seat shown in FIG. It is a side view of the cutting insert with which the insert detachable cutting tool shown in FIG. 1 is mounted. It is a front view of the cutting insert shown in FIG. It is an expansion perspective view of the insert mounting seat periphery of the insert detachable cutting tool to which the clamping mechanism of the cutting insert which is the second embodiment of the present invention is applied. It is a fragmentary perspective view which shows the base surface of the insert attachment seat shown in FIG. It is a side view of the cutting insert with which the insert detachable cutting tool shown in FIG. 7 is mounted. It is a front view of the cutting insert shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Holder 20 Base surface 21 Flat part 22 Fitting part 28 Pressing surface 34 Insert mounting seat 40 Cutting insert 41 Insert main body 42 Cutting blade part 43 Cutting blade 46 Contact surface 47 Part to be fitted

Claims (4)

A clamping mechanism for a cutting insert that is formed by inserting and inserting a cutting insert into an insert mounting seat that is formed at the tip of the holder and includes a pressing surface and a pedestal surface that extend opposite to each other,
A fitting portion is formed at the center portion in the width direction of the pedestal surface, and a fitting portion to be fitted with the fitting portion is formed at the center portion in the width direction of the bottom surface of the cutting insert. And one of the fitted parts is configured in a convex V shape, and the other is configured in a concave V shape,
A flat portion is formed at both ends in the width direction of the pedestal surface, and contact surfaces that are in contact with the flat portion are formed at both ends in the width direction of the bottom surface of the cutting insert. Cutting insert clamping mechanism.   The clamping mechanism for a cutting insert according to claim 1, wherein the fitting portion and the flat portion are formed so as to reach a tip of the pedestal surface.   An insert detachable cutting tool comprising the cutting insert clamping mechanism according to claim 1. A cutting insert attached to the clamping mechanism of the cutting insert according to claim 1 or 2,
A fitting portion configured in a convex V shape or a concave V shape is formed in the center portion in the width direction of the bottom surface, and a contact surface configured in a planar shape is formed in both end portions in the width direction of the bottom surface. A cutting insert that is formed.

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