JP2007203436A - 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 clamps the cutting insert by inserting and nipping it into an insert mounting seat provided with a pressing face and a pedestal face 20 extending opposedly mutually. The cutting insert has an insert main body and a cutting blade part, a cutting blade receiving part 21 abutted on a bottom face of the cutting blade part and a main body receiving part 22 on which a bottom face of the insert main body is abutted, are formed on the pedestal face 20, the bottom face of the cutting blade part and the cutting blade receiving part 21 are formed into a plane shape on which both of them are mutually abutted, and either of the bottom face of the insert main body and the main body receiving part 22 has a projected V shape and the other has a recessed V shape. <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. 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. When cutting is performed with the cutting insert tilted in this way, the cutting angle and clearance angle of the cutting blade will be distorted, the processing accuracy will be degraded, and an excessive load will be applied to the cutting insert. There was a problem that was damaged.

  In particular, in the cutting edge portion provided with the cutting edge, a large cutting resistance may act, and the cutting insert may be inclined due to the main component force of the cutting resistance, or the cutting insert may be displaced due to the back component force. there were. If the position of the cutting insert is not stable in this way, the cutting insert cannot be firmly fixed, chattering occurs during cutting, the processing accuracy of the tool is significantly reduced, and the cutting insert is damaged by chatter. And there was a problem of dropping out.

  The present invention has been made in view of such a situation, and is capable of stably seating the cutting insert and firmly fixing 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 the cutting insert has an insert main body and a cutting edge portion that is disposed on at least one end side of the insert main body and has a cutting edge formed on the pedestal surface. A cutting blade receiving portion that is in contact with the bottom surface of the cutting blade portion and a main body receiving portion that is in contact with the bottom surface of the insert main body are formed, and one of the bottom surface of the insert main body and the main body receiving portion is convex V It has a letter shape, the other has a concave V shape, and the bottom surface of the cutting blade portion and the cutting blade receiving portion are formed in a planar shape capable of contacting each other.

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 that is clamped by the above-described clamping mechanism, and includes an insert main body and a cutting edge portion that is disposed on at least one end side of the insert main body and on which a cutting edge is formed. And the bottom surface of the insert body has a convex V shape or a concave V shape, and the bottom surface of the cutting edge is formed in a planar shape.

According to the clamping mechanism of the cutting insert, the insert detachable cutting tool, and the cutting insert according to the present invention, the bottom surface of the cutting blade portion is formed in a flat shape, and the base portion that is in contact with the bottom surface of the cutting blade portion is cut. Since the blade receiving portion is formed in a flat shape, the seating position when the cutting insert is seated on the pedestal portion is stabilized. In addition, the main component force of the cutting force acting on the cutting edge portion can be received by the cutting blade receiving portion disposed substantially perpendicular to the direction in which the main component force acts, so that the rigidity against the cutting resistance is improved and the cutting is performed. The tilt of the insert can be prevented.
In addition, since one of the bottom surface of the insert main body and the main body receiving portion has a convex V shape and the other has a concave V shape, and these are V-fitted, the position in the width direction between the cutting insert and the base portion The cutting insert can be firmly fixed also in the width direction, and high-precision processing can be performed.

  Here, by forming the main body receiving portion so as to protrude from the plane formed by the cutting blade receiving portion, it is possible to receive the back force of cutting resistance on the surface facing the front end side of the main body receiving portion. The cutting insert can reliably prevent the cutting insert from moving to the rear end side of the cutting tool due to the back component force of the cutting resistance.

  Therefore, according to the present invention, the cutting insert can be stably seated, and the cutting insert clamping mechanism capable of firmly fixing the cutting insert, the insert detachable cutting tool provided with this clamping mechanism, and the cutting An insert can be provided.

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. Extending parallel to the top surface 10A from the position of the shelf portion 11 and the position lower than the shelf portion 11 and the upper surface 10A toward the distal end side (left side in FIG. 2) of the holder 10, A pedestal portion 12 extending flush with the 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 is a cutting blade having a planar shape whose tip side extends in parallel with the upper surface 10 </ b> A of the holder 10, as shown in FIG. 4. A main body receiving portion 22 is formed on the rear end side of the holder 10 of the cutting blade receiving portion 21. In the present embodiment, a flat accommodating portion 23 formed on the same plane as the cutting blade receiving portion 21 is also formed between the main body receiving portion 22 and the cutout portion 14.

  The main body receiving portion 22 is formed so as to protrude upward from the cutting blade receiving portion 21, and is formed in a concave V shape by a pair of inclined surfaces 24, 24 that approach each other as it goes downward. The plane that bisects the concave V-shape is orthogonal to the plane formed by the cutting blade receiver 21. The bottom of the concave V-shaped formed by the main body receiving portion 22 is configured to have the same height as the cutting blade receiving portion 21, and the surface 22A of the main body receiving portion 22 facing the front end side of the holder 10 is shown in FIG. As shown, the two right triangles are opposed to each other.

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 distal end side of the holder 10, and is disposed opposite to the center of the main body receiving portion 22 of the pedestal surface 20 at the distal end. 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 perpendicular 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 bottom surface 42 </ b> A of the cutting edge portion 42 is formed in a planar shape parallel to the longitudinal direction of the insert body 41 and the extending direction of the cutting edge 43.

  The insert main body 41 has a constant width in the longitudinal direction, and the bottom surface 41A of the insert main body 41 approaches each other toward the inner side in the width direction of the insert main body 41 as it goes downward as shown by a dotted line in FIG. A pair of inclined surfaces 46, 46 are provided. The bottom surface 41A of the insert body 41 is formed in a convex V shape that is convex downward by the pair of inclined surfaces 46, 46, and the plane that bisects the convex V shape is the cutting edge. The portion 42 is orthogonal to the plane formed by the bottom surface 42 </ b> A. The angle at which the pair of inclined surfaces 46 and 46 intersect is equal to the intersection angle between the pair of inclined surfaces 24 and 24 forming the main body receiving portion 22. A flat surface 47 extending in parallel with the bottom surface 42 </ b> A of the cutting blade portion 42 is formed at the intersection of the pair of inclined surfaces 46, 46.

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 bottom surface 42A of the cutting edge portion 42 of the cutting insert 40 is disposed so as to contact the cutting edge receiving portion 21 of the pedestal surface 20, and the bottom surface 41A of the insert body 41 having a convex V shape and the concave V shape. It is arranged so that the main body receiving portion 22 of the pedestal surface 20 is fitted. In addition, the cutting blade portion 42 that is not used for cutting among the cutting blades 43 of the cutting insert 40 is disposed in the housing portion 23 formed in the rear end side portion of the pedestal portion 12.

  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, and the insert main body 41 and the main body receiving portion 22 are fitted in a V shape. The cutting edge receiving portion 21 of the pedestal surface 20 is in close contact, 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, the workpiece is cut into the workpiece from the upper surface side of the cutting blade 43 which becomes the rake face 45 of the cutting blade 43, and the main component acts on the cutting blade 43 vertically downward.

In the clamping mechanism of the cutting insert 40 having such a configuration, the bottom surface 42A of the cutting edge portion 42 formed on the cutting insert 40 is formed in a planar shape, and the cutting blade receiving portion 21 of the pedestal surface 20 is planar. 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 cutting blade receiving portion 21 arranged so as to be substantially orthogonal to the main component force. As a result, the rigidity against the cutting resistance is increased, and the cutting insert 40 can be prevented from being damaged, and the cutting insert 40 can be prevented from being inclined or displaced due to the cutting resistance.

Further, the bottom surface 41A of the insert body 41 is formed in a convex V shape, and the main body receiving portion 22 of the pedestal surface 20 is formed in a concave V shape. The relative position in the width direction with respect to the pedestal surface 20 is fixed, the position in the width direction of the cutting blade 43 can be fixed with high accuracy, and high-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 matched.

  Further, since the main body receiving portion 22 is formed so as to protrude from the cutting blade receiving portion 21, even if an excessive back force acts, the main force is applied to the cutting force acting on the cutting edge portion 42. It can be received by the surface 22A facing the front end side of the holder 10 of the receiving portion 22, and the cutting insert 40 can be prevented from moving to the rear end side of the holder 10 due to cutting resistance.

Next, a second embodiment of the present invention will be described. In FIG. 7, the base surface which is 2nd Embodiment is shown. 8 and 9 show a cutting insert seated on this pedestal surface. 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, similarly to the first embodiment described above, a flat cutting edge receiving portion 21 is formed on the tip side portion of the holder 10, and the holder 10 rear end of the cutting edge receiving portion 21 is formed. A main body receiving portion 22 is formed on the side, and the shape of the main body receiving portion 22 is different from that of the first embodiment.

  As shown in FIG. 7, the main body receiving portion 22 is formed so as to protrude upward from the cutting blade receiving portion 21, and a pair that approaches each other toward the inner side in the width direction of the pedestal portion 20 as it goes upward. Slopes 24, 24 are provided. The main body receiving portion 22 is formed in a convex V shape that is convex upward by the pair of inclined surfaces 24, 24. A flat surface 35 extending in parallel with the cutting blade receiving portion 21 is formed at the intersection of the pair of inclined surfaces. Thereby, 22 A of surfaces which face the holder 10 front end side of the main body receiving part 22 are made into the trapezoid which has two oblique sides, as shown in FIG.

  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 has a substantially outer shape as shown in FIG. This is a dog bone type insert having an insert body 41 formed in a square bar shape and cutting edge portions 42 disposed at both ends of the insert body 41.

  The insert main body 41 has a constant width in the longitudinal direction, and the bottom surface 41A of the insert main body 41 approaches each other toward the inner side in the width direction of the insert main body 41 as shown upward by a dotted line in FIG. A pair of inclined surfaces 46, 46 are provided. The bottom surface 41 </ b> A of the insert body 41 is formed in a concave V shape that is recessed upward by the pair of inclined surfaces 46 and 46.

  The cutting insert 40 is seated on the pedestal surface 20, and the bottom surface 42A of the cutting edge portion 42 of the cutting insert 40 is disposed so as to abut against the cutting edge receiving portion 21 of the pedestal surface 20, and a concave V-shaped insert. It arrange | positions so that the bottom face 41A of the main body 41 and the main body receiving part 22 of the base surface 20 which makes 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 bottom surface 41A of the insert main body 41 and the main body receiving portion 22 are V-shaped, and the pressing surface 28 and the pedestal surface 20 And the cutting insert 41 is clamped.

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.
Further, since the surface 22A of the main body receiving portion 22 facing the front end side of the holder 10 has a trapezoidal shape, it is possible to stably receive the back component force of the cutting resistance as compared with the first embodiment.

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 according to the first and second embodiments of the present invention is applied. It is a side 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. It is a fragmentary perspective view which shows the base surface of the insert mounting seat shown in FIG. FIG. 3 is a front view around the insert mounting seat shown in FIG. 2. It is a side view of the cutting insert with which the insert mounting seat shown in FIG. 2 is mounted. It is a front view of the cutting insert shown in FIG. It is a fragmentary perspective view which shows the base surface of the insert mounting seat of the insert detachable cutting tool to which the clamp mechanism of the cutting insert which is the 2nd Embodiment of this invention is applied. It is a side view of the cutting insert with which the insert mounting seat 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 Cutting edge receiving part 22 Main body receiving part 28 Pressing surface 34 Insert mounting seat 40 Cutting insert 41 Insert main body 41A Bottom face of insert main body 42 Cutting edge part 42A Bottom face of cutting edge part 43 Cutting edge

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,
The cutting insert has an insert body, and a cutting edge portion disposed on at least one end side of the insert body and formed with a cutting edge,
The pedestal surface is formed with a cutting blade receiving portion that contacts the bottom surface of the cutting blade portion and a main body receiving portion that contacts the bottom surface of the insert main body,
One of the bottom surface of the insert body and the body receiving portion has a convex V shape, and the other has a concave V shape,
The cutting insert clamping mechanism according to claim 1, wherein the bottom surface of the cutting blade portion and the cutting blade receiving portion are formed in a planar shape capable of contacting each other.   The clamping mechanism for a cutting insert according to claim 1, wherein the main body receiving portion is formed so as to protrude from a plane formed by the cutting blade receiving portion.   An insert detachable cutting tool comprising the cutting insert clamping mechanism according to claim 1. A cutting insert clamped to the clamping mechanism of the cutting insert according to claim 1 or 2,
An insert body, and a cutting blade portion disposed on at least one end side of the insert body and formed with a cutting blade;
The bottom surface of the insert body has a convex V shape or a concave V shape, and the bottom surface of the cutting edge portion is formed in a flat shape.

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