JP4548132B2

JP4548132B2 - Cutting insert clamping mechanism

Info

Publication number: JP4548132B2
Application number: JP2005024109A
Authority: JP
Inventors: 秀彦長屋; 典夫麻生; 康晴今井
Original assignee: Mitsubishi Materials Corp
Current assignee: Mitsubishi Materials Corp
Priority date: 2005-01-31
Filing date: 2005-01-31
Publication date: 2010-09-22
Anticipated expiration: 2025-01-31
Also published as: JP2006205347A

Description

本発明は、例えば被削材の溝入れや突っ切りに用いられるインサート着脱式工具において、切削インサートをホルダのインサート取付座にクランプして着脱可能に取り付けるための切削インサートのクランプ機構に関するものである。 The present invention relates to a clamping mechanism for a cutting insert for detachably attaching a cutting insert to an insert mounting seat of a holder in, for example, an insert detachable tool used for grooving or parting off a work material.

このような溝入れや突っ切りに用いられる切削インサートのクランプ機構としては、ホルダの先端部に先端側に開口する一対の顎部が弾性変形可能に形成されて、この一対の顎部のうち、一方の顎部には押圧面を有する押圧部が設けられ、他方の顎部には台座面を有する台座が設けられ、これら押圧面と着座面とが互いに対向するように形成されており、この押圧部と台座とがインサート取付座を構成し、このインサート取付座に切削インサートを挿入して上記一対の顎部を当接方向に接近させて、これらの顎部に形成された押圧面と台座面とを、切削インサートに形成された被押圧面と着座面とにそれぞれ当接させて押圧し、クランプするものが知られている。 As a clamping mechanism of a cutting insert used for such grooving or parting off, a pair of jaws that open to the tip side of the holder is formed to be elastically deformable, and one of the pair of jaws is A pressing portion having a pressing surface is provided on the jaw portion of the chin, and a pedestal having a pedestal surface is provided on the other jaw portion, and the pressing surface and the seating surface are formed so as to face each other. The pedestal and the pedestal constitute an insert mounting seat, a cutting insert is inserted into the insert mounting seat, the pair of jaws are brought closer to the contact direction, and the pressing surface and the pedestal surface formed on these jaws Are pressed and brought into contact with a pressed surface and a seating surface formed on the cutting insert, and are clamped.

そして、一般的に上記顎部を弾性変形させて切削インサートをクランプするには、例えば特許文献１または特許文献２に記載のクランプ機構のように、一方の顎部に挿通されたクランプネジを他方の顎部にねじ込むことにより、この一方の顎部を他方の顎部に向けて撓ませて接近させる手段が採られている。つまり、顎部の付け根部分を支点として、クランプネジを力点として、上記一方の顎部の押圧面を作用点として、該一方の顎部を他方の顎部に向けて、つまり当接方向に沿って弾性変形させて切削インサートをクランプするものである。 In general, in order to clamp the cutting insert by elastically deforming the above-described jaw portion, for example, as in the clamp mechanism described in Patent Literature 1 or Patent Literature 2, a clamping screw inserted into one jaw portion is used as the other. A means is adopted in which the one jaw portion is bent toward the other jaw portion by being screwed into the other jaw portion. That is, with the base portion of the jaw as a fulcrum, the clamp screw as a force point, the pressing surface of the one jaw as an action point, the one jaw toward the other jaw, that is, along the contact direction Thus, the cutting insert is clamped by elastic deformation.

ここで、上記のインサート取付座は、ホルダの幅方向の一端部から工具先端部に延びるように、すなわち、ホルダの軸線からずれた位置から、ホルダの幅よりも狭い幅で、工具の先端側へ突出するように形成されており、切削インサートは、ホルダの軸線からずれた位置でクランプされている。また、上記のクランプネジは、ネジを安定して保持するために幅広のホルダの幅方向中央部に、すなわち、ホルダの軸線近傍に、顎部を弾性変形させる方向に沿って設けられている。 Here, the insert mounting seat extends from one end in the width direction of the holder to the tool tip, that is, from a position shifted from the axis of the holder, with a width narrower than the width of the holder, The cutting insert is clamped at a position shifted from the axis of the holder. Further, the clamp screw is provided in the width direction central portion of the wide holder, that is, in the vicinity of the axis of the holder along the direction in which the jaw portion is elastically deformed in order to stably hold the screw.

上記のクランプ機構を有するインサート着脱式工具は、切削インサートをホルダの先端部に形成された一対の顎部で挟み込むことで固定し、旋盤又はマシニングセンタ等の工作機械に支持されて、高速に回転するワークに切削インサートが押し付けられた状態でワークに対して相対的に移動させられることで、切削インサートの切刃によってワークの外面や端面を切削するものである。
特表２００１−５１５７９５号公報特開２００１−６２６０８号公報 The insert detachable tool having the clamp mechanism described above is fixed by sandwiching the cutting insert between a pair of jaws formed at the tip of the holder, and is supported by a machine tool such as a lathe or a machining center to rotate at high speed. 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 while the cutting insert is pressed against the workpiece.
JP-T-2001-515795 JP 2001-62608 A

ところが、上記のクランプ機構では、インサート取付座の押圧面（作用点）が、顎部を弾性変形させるクランプネジ（力点）が設けられた部分と顎部の付け根部分（支点）とが位置するホルダの軸線近傍から離れた位置に配置されているので、一対の顎部を接近させて上記一方の顎部の押圧面が切削インサートの被押圧面に接触した後にさらにクランプネジをねじ込むと、上記一方の顎部には曲げモーメントが生じ、上記一方の顎部の押圧面と切削インサートの被押圧面とが十分に当接されないことがあった。 However, in the clamp mechanism described above, the pressing surface (working point) of the insert mounting seat is a holder in which a portion provided with a clamp screw (power point) for elastically deforming the jaw and a base portion (fulcrum) of the jaw are located. When the clamp screw is further screwed in after the pair of jaws are brought close to each other and the pressing surface of the one jaw contacts the pressed surface of the cutting insert, the one of the jaws There is a case where a bending moment is generated in the jaw portion, and the pressing surface of the one jaw portion is not sufficiently brought into contact with the pressed surface of the cutting insert.

そして、上記の状態で切削インサートが取り付けられたインサート着脱式工具では、切削インサートが強固に固定されておらず、切削加工時にビビリが生じ、その工具の加工精度が著しく低下するといった問題があった。また、ビビリによって切削インサートが破損したり、切削インサートが脱落したりするといった問題があった。 In the insert detachable tool in which the cutting insert is attached in the above state, the cutting insert is not firmly fixed, chattering occurs during cutting, and the processing accuracy of the tool is significantly reduced. . Moreover, there existed a problem that a cutting insert was damaged by chatter and a cutting insert fell off.

さらに、一方の顎部に大きな曲げモーメントが生じて、押圧部が台座に対して傾いた状態で切削インサートを押圧した場合には、切削インサートが傾いてしまい、切刃の切り込み角や逃げ角に狂いが生ずるおそれがあった。この場合には、インサート着脱式工具の加工精度が劣化するとともに、切削インサートに過大な負荷が掛かり、やはり切削インサートが破損したり脱落したりするといった問題があった。 In addition, when a large bending moment is generated in one jaw and the cutting insert is pressed while the pressing part is tilted with respect to the pedestal, the cutting insert is tilted, resulting in a cutting angle or clearance angle of the cutting blade. There was a risk of going crazy. In this case, the machining accuracy of the insert detachable tool deteriorates, and an excessive load is applied to the cutting insert, and the cutting insert is also damaged or dropped off.

本発明は、上記の状況を鑑みてなされたものであって、切削インサートの被押圧面とインサート取付座の押圧面とが十分に当接され、切削インサートを安定して固定することができる切削インサートのクランプ機構を提供することを目的とする。 The present invention has been made in view of the above situation, and a cutting surface in which a pressed surface of a cutting insert and a pressing surface of an insert mounting seat are sufficiently brought into contact with each other and the cutting insert can be stably fixed. An object of the present invention is to provide an insert clamping mechanism.

上記の課題を解決するために、本発明は、ホルダの先端部に形成され、互いに対向して延びる押圧面と台座面とを備えたインサート取付座に、前記押圧面と前記台座面とにそれぞれ当接する被押圧面と着座面とを備えた切削インサートを、挿入して挟み込むことによりクランプする切削インサートのクランプ機構であって、前記ホルダの先端部には、一方の顎部と他方の顎部とを有する一対の顎部が形成され、前記他方の顎部には、前記台座面を有する台座が設けられ、前記一方の顎部には、前記押圧面を有する押圧部が設けられるとともに、これら一対の顎部には、前記押圧部を弾性変形させて前記台座に向けて当接方向に接近させるクランプネジが、前記インサート取付座に対して、前記押圧面および前記台座面の幅方向側方に隣接するように挿通されていて、このクランプネジは、前記一方の顎部側に向かうに従い前記押圧部の前記押圧面に近づくように傾斜して設けられており、前記クランプネジは、雄ネジ部と該雄ネジ部よりも大径とされた頭部を有し、前記一方の顎部には、前記雄ネジ部が螺着される雌ネジ部が設けられるとともに、前記他方の顎部には、前記一方の顎部側に向けて開口する前記頭部よりも小径で前記雄ネジ部が緩挿可能な小径部と、前記一方の顎部とは反対側に開口して前記頭部を収容可能な大径部とを有する収容孔が形成されていて、前記収容孔の前記小径部と前記大径部との間の部分と、前記頭部の前記一方の顎部側を向く部分とのうち少なくとも一方が、これらの部分の双方がテーパー角の等しい凹凸円錐面状である組み合わせを除いて、前記一方の顎部側に向かうに従い漸次径が小さくなるように形成されており、前記クランプネジの前記頭部の前記一方の顎部側を向く部分が凸円錐面状部または凸曲面状部とされるとともに、前記収容孔の前記小径部と前記大径部の間の部分は、該収容孔の中心線に沿った断面が内周側に凸曲しつつ前記一方の顎部側に向かうに従い縮径する曲面状とされていることを特徴とする。
In order to solve the above-described problems, the present invention provides an insert mounting seat formed on a tip portion of a holder and extending opposite to each other on an insert mounting seat, and each of the pressing surface and the pedestal surface. A clamping mechanism for a cutting insert that clamps by inserting and sandwiching a cutting insert having a pressed surface and a seating surface that are in contact with each other, and at the tip of the holder, one jaw and the other jaw A pair of jaws is formed, the other jaw is provided with a pedestal having the pedestal surface, and the one jaw is provided with a pressing part having the pressing surface. A clamp screw that elastically deforms the pressing portion and approaches the pedestal in the abutting direction is provided on the pair of jaw portions, with respect to the insert mounting seat, in the lateral direction of the pressing surface and the pedestal surface. Adjacent to The clamp screw is provided so as to be inclined so as to approach the pressing surface of the pressing portion toward the one jaw portion side, and the clamp screw includes a male screw portion and the male screw portion. A head portion having a diameter larger than that of the screw portion; the one jaw portion is provided with a female screw portion to which the male screw portion is screwed; and the other jaw portion is provided with the one side A small-diameter portion that is smaller in diameter than the head that opens toward the jaw portion side and into which the male screw portion can be loosely inserted, and a large-diameter portion that opens on the opposite side to the one jaw portion and can accommodate the head portion. An accommodation hole having a diameter portion, and at least one of a portion between the small diameter portion and the large diameter portion of the accommodation hole and a portion facing the one jaw portion side of the head However, except for the combination in which both of these parts are concave and convex conical surfaces with the same taper angle, Is formed so as to gradually diameter decreases toward the one jaw portion, said portions facing one jaw side of the head of the clamping screw is a convex conical surface-like portion or a convex curved surface portion In addition, the portion between the small-diameter portion and the large-diameter portion of the accommodation hole is contracted toward the one jaw portion side while a cross section along the center line of the accommodation hole is bent toward the inner peripheral side. It is characterized by having a curved surface with a diameter .

上記の切削インサートのクランプ機構では、クランプネジが、前記インサート取付座に対して、前記押圧面および前記台座面の幅方向側方に隣接するように挿通されていて、このクランプネジは、前記一方の顎部側に向かうに従い前記押圧部の前記押圧面に近づくように傾斜して設けられているので、作用点となる押圧部と力点となるクランプネジとの距離を小さくすることができ、一方の顎部を他方の顎部に近接する方向（当接方向）に弾性変形させた場合に、一方の顎部に負荷される曲げモーメントを低減でき、押圧部の押圧面と切削インサートの被押圧面とを確実に当接させることができ、切削インサートを強固に固定することができる。 In the cutting insert clamping mechanism, a clamp screw is inserted into the insert mounting seat so as to be adjacent to the lateral side of the pressing surface and the pedestal surface. Since it is provided so as to be closer to the pressing surface of the pressing portion as it goes to the jaw side, the distance between the pressing portion serving as the action point and the clamp screw serving as the force point can be reduced. When one jaw part is elastically deformed in the direction approaching the other jaw part (contacting direction), the bending moment applied to one jaw part can be reduced, and the pressing surface of the pressing part and the pressed insert of the cutting insert The surface can be reliably brought into contact with the cutting insert, and the cutting insert can be firmly fixed.

また、前記クランプネジは、雄ネジ部と該雄ネジ部よりも大径とされた頭部を有し、前記一方の顎部に、前記雄ネジ部が螺着される雌ネジ部が設けられるとともに、前記他方の顎部には、前記一方の顎部側に向けて開口する前記頭部よりも小径で前記雄ネジ部が緩挿可能な小径部と、前記一方の顎部とは反対側に開口して前記頭部を収容可能な大径部とを有する収容孔が形成することにより、クランプネジの頭部が他方の顎部に収容され、一方の顎部には頭部よりも小径の雄ネジ部が螺着されるので、一方の顎部に形成される雌ネジ部の大きさが小さく、この雌ネジ部を押圧部の近傍に近づけることができ、曲げモーメントを一層低減することができる。また、クランプネジの頭部を、収容孔の小径部と大径部との段差部に当接させることができ、押圧部を引き込むことができるので、切削インサートを固定することができる。 The clamp screw has a male screw portion and a head having a larger diameter than the male screw portion, and a female screw portion to which the male screw portion is screwed is provided on the one jaw portion. In addition, the other jaw portion has a small-diameter portion that is smaller in diameter than the head portion that opens toward the one jaw portion side and into which the male screw portion can be loosely inserted, and is opposite to the one jaw portion. A housing hole having a large-diameter portion capable of accommodating the head portion is formed, so that the head portion of the clamp screw is accommodated in the other jaw portion, and the one jaw portion has a smaller diameter than the head portion. Since the male screw part is screwed, the size of the female screw part formed on one jaw part is small, the female screw part can be brought close to the pressing part, and the bending moment is further reduced. Can do. Moreover, since the head part of a clamp screw can be contact | abutted to the level | step-difference part of the small diameter part and large diameter part of an accommodation hole, and a press part can be drawn in, a cutting insert can be fixed.

また、前記収容孔の前記小径部と前記大径部との間の部分と、前記頭部の前記一方の顎部側を向く部分とのうち少なくとも一方を、前記一方の顎部に向かうに従い漸次径が小さくなるように形成することにより、雄ネジ部が螺着した一方の顎部のネジ孔の中心線と他方の顎部の収容孔の中心線とが該顎部の弾性変形によって傾きを生じたとしても、この傾きに追従させてクランプネジを傾動させることができ、クランプネジに曲がりが生じたりすることを防ぐことができるとともに、こうしてクランプネジが傾動した状態でも頭部と収容孔とを少なくとも線接触で当接させることができるので、クランプ安定性を確実に維持することが可能となる。 Further, at least one of the portion between the small-diameter portion and the large-diameter portion of the accommodation hole and the portion facing the one jaw portion of the head is gradually increased toward the one jaw portion. By forming the diameter to be small, the center line of the screw hole of one jaw part to which the male screw part is screwed and the center line of the receiving hole of the other jaw part are inclined by elastic deformation of the jaw part. Even if it occurs, the clamp screw can be tilted by following this tilt, and it is possible to prevent the clamp screw from being bent, and even if the clamp screw is tilted, the head and the receiving hole Can be brought into contact with each other at least by line contact, so that the clamp stability can be reliably maintained.

そして、このように収容孔の大小径部との間やクランプネジ頭部の径を小さくするには、例えばクランプネジの頭部にあっては一方の顎部側を向く部分を凸球面状や凸円錐面状に形成すればよい。すなわち、こうしてクランプネジ頭部の一方の顎部側を凸円錐面状部または凸曲面状部とするとともに、収容孔の大小径部間の部分は該収容孔の中心線に沿った断面が内周側に凸曲しつつ一方の顎部側に向かうに従い縮径する曲面状とされるようにする。
Then, in order to reduce the size of or between the clamping screw head of the large diameter portion of the thus accommodating holes, in the head of the click Ranpuneji For example one jaw side parts convex spherical facing Or a convex conical surface. That is, one jaw portion side of the clamp screw head is formed as a convex conical surface portion or a convex curved surface portion, and the section between the large and small diameter portions of the accommodation hole has an inner section along the center line of the accommodation hole. is a peripheral side curved surface reduced in diameter toward the one jaw portion side while Totsukyoku to so that.

また、前記クランプネジの前記雄ネジ部の中心線を含み、前記インサートの厚み方向の中心面に垂直に延びる面と、前記インサートの幅方向の中心面とのなす角度を５°〜７０°の範囲内とすることにより、一方の顎部が他方の顎部に近づくように弾性変形された際に、一方の顎部に発生する曲げモーメントを確実に低減でき、押圧部の押圧面とインサートの被押圧面とを確実に当接させることができる。 In addition, an angle formed by a surface including a center line of the male screw portion of the clamp screw and extending perpendicularly to a center surface in the thickness direction of the insert and a center surface in the width direction of the insert is 5 ° to 70 °. By making it within the range, when one jaw part is elastically deformed so as to approach the other jaw part, the bending moment generated in one jaw part can be surely reduced, and the pressing surface of the pressing part and the insert The pressed surface can be reliably brought into contact with the pressed surface.

また、前記クランプネジの前記雄ネジ部の中心線を含み、前記インサートの厚み方向の中心面に垂直に延びる断面において、前記クランプネジの前記雄ネジ部の中心線と、前記インサートの厚さ方向の中心面と直交する線とのなす角度を２°〜４５°の範囲内とすることにより、一方の顎部が他方の顎部に近づくように弾性変形された際の曲げモーメントの発生をより確実に低減し、押圧部の押圧面とインサートの被押圧面とをより確実に当接させることができる。 In addition, in the cross section including the center line of the male screw portion of the clamp screw and extending perpendicularly to the center plane in the thickness direction of the insert, the center line of the male screw portion of the clamp screw and the thickness direction of the insert By making the angle formed by the line perpendicular to the center plane of the tube within the range of 2 ° to 45 °, the bending moment is more easily generated when one jaw is elastically deformed so as to approach the other jaw. It can reduce reliably and can make the press surface of a press part and the to-be-pressed surface of an insert contact more reliably.

したがって、本発明によれば、切削インサートの被押圧面とインサート取付座の押圧面とが十分に当接され、切削インサートを安定して固定することができる切削インサートのクランプ機構を提供することができる。 Therefore, according to the present invention, it is possible to provide a cutting insert clamping mechanism in which the pressed surface of the cutting insert and the pressing surface of the insert mounting seat are sufficiently brought into contact with each other and the cutting insert can be stably fixed. it can.

本発明の実施形態を説明する上での参考例について、図面を参照にして説明する。図１ないし図４に、この参考例のクランプ機構を適用したインサート着脱式工具を示す。
このインサート着脱式工具において、ホルダ１は鋼材等から形成され、図１、図２に示すように後端側（図１、図２において右側）に軸線Ｌに沿って延びる四角柱状のシャンク部２を有するとともに、先端部（図１、図２において左側部分）は、上面視に図１に示すようにこのシャンク部２の一方の側面２Ａから僅かに側方に突出し、かつこの側面２Ａ側からの側面視には図２に示すように上部がシャンク部２の上面２Ｂから盛り上がるように突出したヘッド部３とされている。 For reference example in describing an embodiment of the present invention will be described with reference to the drawings. 1 to 4 show an insert detachable tool to which the clamping mechanism of this reference example is applied.
In this insert detachable tool, the holder 1 is formed of a steel material or the like, and as shown in FIGS. 1 and 2, a square columnar shank portion 2 extending along the axis L on the rear end side (right side in FIGS. 1 and 2). 1 and the front end portion (left side portion in FIGS. 1 and 2) slightly protrudes laterally from one side surface 2A of the shank portion 2 as viewed from above and from the side surface 2A side as shown in FIG. As shown in FIG. 2, the head portion 3 protrudes so that the upper portion rises from the upper surface 2 B of the shank portion 2.

このヘッド部３には、その先端側からシャンク部２の上面２Ｂの延長面に沿うようにスリット３Ａが形成されていて、このスリット３Ａよりも上側の上顎部３Ｂは、下側の下顎部３Ｃよりも上記延長面に直交する方向の厚さが図２に示すように薄くされている。
また、スリット３Ａにより画定される上顎部３Ｂとシャンク部２側との接続部分３Ｄの断面積についても、下顎部３Ｃとシャンク部２との接続部分の断面積より小さくされていて、上顎部３Ｂはこの接続部分３Ｄを支点として下顎部３Ｃ側に向けて撓むように弾性変形可能とされている。 The head portion 3 is formed with a slit 3A along the extended surface of the upper surface 2B of the shank portion 2 from the front end side. The upper jaw portion 3B above the slit 3A is the lower lower jaw portion 3C. Further, the thickness in the direction orthogonal to the extended surface is made thinner as shown in FIG.
Further, the cross-sectional area of the connecting portion 3D between the upper jaw 3B and the shank portion 2 defined by the slit 3A is also smaller than the cross-sectional area of the connecting portion between the lower jaw 3C and the shank portion 2, and the upper jaw 3B. Is elastically deformable so as to bend toward the lower jaw 3C side with this connecting portion 3D as a fulcrum.

下顎部３Ｃのシャンク部２の一方の側面側２Ａの先端部には、その先端側がシャンク部２の軸線Ｌに平行に方形平板状に延びるように台座４がシャンク部２と一体に形成され、この台座４の上面が当接面（台座面４Ａ）とされ、下顎部３Ｃの先端からホルダ１の長手方向に上記スリット３Ａの中程までに延びるように形成されている。そして、この台座面４Ａは、軸線Ｌに垂直な断面において、上方に向かうに従い互いに近づく一対の斜面によって凸Ｖ字状に形成されている。 A pedestal 4 is formed integrally with the shank part 2 at the tip part of one side 2A of the shank part 2 of the lower jaw part 3C so that the tip side extends in a rectangular flat plate shape parallel to the axis L of the shank part 2, The upper surface of the pedestal 4 is a contact surface (pedestal surface 4A), and is formed so as to extend from the tip of the lower jaw 3C to the middle of the slit 3A in the longitudinal direction of the holder 1. The pedestal surface 4A is formed in a convex V shape by a pair of inclined surfaces that approach each other as it goes upward in a cross section perpendicular to the axis L.

一方、上顎部３Ｂのシャンク部２の一方の側面２Ａ側の先端部には、下顎部３Ｃに設けられた台座４に沿うように先端側に向かうに従い下方に向かう斜辺を備えた三角形板状に形成された押圧部５がシャンク部２と一体に形成され、ただしその先端は下顎部３Ｃの先端よりも後退させられており、この押圧部５の台座４側を向く面が当接面（押圧面５Ａ）とされ、下顎部３Ｃの台座面４Ａの長手方向中央部よりも先端側寄りから台座面４Ａの後端よりも僅かに先端側にまで延設されている。押圧部５に形成された押圧面５Ａは、下方に向かうに従い互いに近づく一対の斜面によって凸Ｖ字状に形成されている。 On the other hand, the tip portion on the side surface 2A side of the shank portion 2 of the upper jaw portion 3B has a triangular plate shape having a hypotenuse that goes downward as it goes to the tip end side along the pedestal 4 provided on the lower jaw portion 3C. The formed pressing portion 5 is formed integrally with the shank portion 2, but the tip thereof is retracted from the tip of the lower jaw portion 3 C, and the surface of the pressing portion 5 facing the base 4 side is a contact surface (pressing surface). 5A), and extends from a position closer to the front end side than the central portion in the longitudinal direction of the pedestal surface 4A of the lower jaw part 3C to a position slightly closer to the front end side than the rear end of the pedestal face 4A. The pressing surface 5A formed on the pressing portion 5 is formed in a convex V shape by a pair of inclined surfaces that approach each other as it goes downward.

このように、台座４に形成された台座面４Ａと押圧部５に形成された押圧面５Ａとは、互いに対向するように配置されており、インサート取付座６を構成している。
したがって、本参考例においては、上記上顎部３Ｂが一方の顎部とされ、上記下顎部３Ｃが他方の顎部とされており、押圧部５の押圧面５Ａと台座４の台座面４Ａとが対向する面に垂直な方向がその当接方向とされ、上顎部３Ｂはこの当接方向に弾性変形可能とされている。 Thus, the pedestal surface 4A formed on the pedestal 4 and the pressing surface 5A formed on the pressing portion 5 are arranged so as to face each other, and constitute the insert mounting seat 6.
Therefore, in this reference example , the upper jaw portion 3B is one jaw portion, the lower jaw portion 3C is the other jaw portion, and the pressing surface 5A of the pressing portion 5 and the pedestal surface 4A of the pedestal 4 are provided. The direction perpendicular to the opposing surface is the contact direction, and the upper jaw 3B is elastically deformable in this contact direction.

上記の構成のインサート取付座６に取り付けられる切削インサート１１は、超硬合金等の硬質材料で構成されており、その外形が略角棒状に形成されたインサート本体１２と切刃部１４とを有する。インサート本体１２は、その長手方向で幅が一定とされ、インサート本体１２の長手方向中央部には上方に突出した凸部１３が備えられており、この凸部１３の上面には、インサート本体１２の幅方向内側に向かうに従い下方に向かうように互いに近づく一対の斜面によって凹Ｖ字状に形成されている。そして、インサート本体１２の下面には、図３に示すようにインサート本体１２の幅方向内側に向かうに従い上方に向かうように互いに近づく一対の斜面が設けられており、この一対の斜面によって凹Ｖ字状に形成されていて、これが着座面１２Ａをなしている。 The cutting insert 11 attached to the insert mounting seat 6 having the above-described configuration is made of a hard material such as cemented carbide, and has an insert body 12 and a cutting edge portion 14 whose outer shape is formed in a substantially square bar shape. . The insert body 12 has a constant width in the longitudinal direction. The insert body 12 is provided with a convex portion 13 projecting upward at a central portion of the insert body 12 in the longitudinal direction. It is formed in a concave V shape by a pair of inclined surfaces that approach each other so as to go downward as it goes inward in the width direction. As shown in FIG. 3, a pair of slopes approaching each other so as to go upward as they go inward in the width direction of the insert body 12 are provided on the lower surface of the insert body 12. The seating surface 12A is formed.

インサート本体１２の長手方向の両端上面側には切刃部１４が配置され、この切刃部１４の上面端部には、インサート本体１２の長手方向に直交する方向に延びる切刃１５がそれぞれ形成されており、これらの切刃１５に連なり長手方向の一方の端部および他方の端部を向く面は切刃１５の逃げ面１６とされて、図２に示すようにインサート本体１２の下側に向かうに従いインサート本体１２の長手方向の中央部側に近づくように傾斜させられていてポジの逃げ角が与えられている。 Cutting blade portions 14 are disposed on the upper surface sides of both ends in the longitudinal direction of the insert main body 12, and cutting blades 15 extending in a direction perpendicular to the longitudinal direction of the insert main body 12 are formed on the upper surface end portions of the cutting blade portions 14, respectively. The surfaces that are continuous with these cutting blades 15 and face one end and the other end in the longitudinal direction are flank surfaces 16 of the cutting blade 15, as shown in FIG. It is inclined so that it may approach the center part side of the longitudinal direction of the insert main body 12 as it goes to, and the positive clearance angle is given.

また、切刃１５に連なるように切削インサート１１の上面側に延びる面がすくい面１７とされており、このすくい面１７は、図１に示すように上面視して切刃１５側に向かうに従いインサート本体１２の幅よりも広幅になるような等脚台形状に形成され、長手方向において、凸部１３の上面よりも短くなるように配置されている。つまり、切削インサート１１は、その長手方向の中心部に対して対称となるように形成されたドッグボーン形インサートである。 Further, a surface extending to the upper surface side of the cutting insert 11 so as to be continuous with the cutting blade 15 is a rake surface 17, and this rake surface 17 is viewed from the top as shown in FIG. It is formed in an isosceles trapezoidal shape so as to be wider than the width of the insert body 12, and is disposed so as to be shorter than the upper surface of the convex portion 13 in the longitudinal direction. That is, the cutting insert 11 is a dog bone type insert formed so as to be symmetric with respect to the central portion in the longitudinal direction.

ここで、上記インサート取付座６のクランプ手段２１として、ホルダ１先端部のヘッド部３に下方から挿通されるクランプネジ２２が設けられており、該クランプネジ２２は、スリット３Ａを超えて上顎部３Ｂに螺着される雄ネジ部２２Ａと、この雄ネジ部２２Ａよりも大径で下顎部３Ｃに収容される頭部２２Ｂとを備えており、クランプネジ２２の両端のこれらの雄ネジ部２２Ａおよび頭部２２Ｂの端面には、レンチ等の汎用の作業用工具に係合する係合孔２２Ｃがそれぞれ形成されている。なお、本参考例においては、雄ネジ部２２Ａには左ネジが形成されており、頭部２２Ｂは、その外形が雄ネジ部２２Ａの中心線Ｏを中心とした略厚肉円盤状をなすようにされている。 Here, as the clamping means 21 of the insert mounting seat 6, a clamp screw 22 inserted from below into the head portion 3 at the tip of the holder 1 is provided, and the clamp screw 22 extends beyond the slit 3A to the upper jaw portion. A male screw portion 22A screwed to 3B and a head 22B having a diameter larger than that of the male screw portion 22A and housed in the lower jaw portion 3C are provided. These male screw portions 22A at both ends of the clamp screw 22 are provided. In addition, engagement holes 22C that engage with general-purpose work tools such as a wrench are formed on the end surfaces of the head 22B. In this reference example , the male screw portion 22A is formed with a left-hand thread, and the head portion 22B has a substantially thick disk shape whose outer shape is centered on the center line O of the male screw portion 22A. Has been.

これに対してヘッド部３には、このクランプネジ２２が取り付けられる取付孔２３が、上面視して図１に示すようにインサート取付座６に対して、押圧面および台座面の幅方向（図１において上下方向）の側方（図１では上側）に隣接するように、より詳しくは、インサート取付座６に取り付けられた切削インサート１１の長手方向両端部の間において前記幅方向側方に位置するように形成されている。 On the other hand, the mounting hole 23 to which the clamp screw 22 is attached is formed in the head portion 3 in the width direction of the pressing surface and the pedestal surface with respect to the insert mounting seat 6 as shown in FIG. More specifically, it is positioned on the lateral side between the longitudinal ends of the cutting insert 11 attached to the insert mounting seat 6 so as to be adjacent to the lateral side (upper direction in FIG. 1). It is formed to do.

上記の取付孔２３は、上顎部３Ｂ側の雄ネジ部２２Ａが螺着されるネジ孔２４と、このネジ孔２４に同軸に形成されて下顎部３Ｃ側の頭部２２Ｂが収容される収容孔２５とから構成されている。上記のネジ孔２４は、スリット３Ａから上顎部３Ｂを貫通して、スリット３Ａと平行とされたヘッド部３の上面３Ｅ（上顎部３Ｂの上面）に開口させられており、クランプネジ２２の雄ネジ部２２Ａの端面に設けられた係合孔２２Ｃが、このネジ孔２４を通じてヘッド部３の上面３Ｅ側に向けて露呈されている。 The mounting hole 23 includes a screw hole 24 into which the male screw portion 22A on the upper jaw portion 3B side is screwed, and an accommodation hole that is formed coaxially with the screw hole 24 and accommodates the head portion 22B on the lower jaw portion 3C side. 25. The screw hole 24 passes through the upper jaw portion 3B from the slit 3A and is opened on the upper surface 3E of the head portion 3 (upper surface of the upper jaw portion 3B) parallel to the slit 3A. An engagement hole 22 C provided on the end surface of the screw portion 22 A is exposed through the screw hole 24 toward the upper surface 3 E side of the head portion 3.

一方、収容孔２５は、下顎部３Ｃを貫通してヘッド部３の下面３Ｆ（下顎部３Ｃの下面）から上顎部３Ｂ側に向けスリット３Ａに開口させられており、このスリット３Ａ側から下方に向けて順に、クランプネジ２２の頭部２２Ｂよりも小径で雄ネジ部２２Ａよりは僅かに大径の内径を有する小径部２５Ａと、この小径部２５Ａより大径でクランプネジ２２の頭部２２Ｂを収容可能な内径を有する大径部２５Ｂとから構成されている。したがって、上記小径部２５Ａにはクランプネジ２２の雄ネジ部２２Ａが僅かなクリアランスを有して緩挿可能とされる。なお、これら小径部２５Ａと大径部２５Ｂとの接続部分は、本参考例では上記中心線Ｏに垂直となる円環状の平坦面２５Ｃとされている。 On the other hand, the accommodation hole 25 is opened to the slit 3A from the lower surface 3F of the head portion 3 (the lower surface of the lower jaw portion 3C) to the upper jaw portion 3B side through the lower jaw portion 3C, and downward from the slit 3A side. In turn, a small diameter portion 25A having a smaller diameter than the head portion 22B of the clamp screw 22 and a slightly larger inner diameter than the male screw portion 22A, and a head portion 22B of the clamp screw 22 having a larger diameter than the small diameter portion 25A. The large-diameter portion 25B has an inner diameter that can be accommodated. Therefore, the male screw portion 22A of the clamp screw 22 can be loosely inserted into the small diameter portion 25A with a slight clearance. The connecting portion between the small diameter portion 25A and the large diameter portion 25B is an annular flat surface 25C that is perpendicular to the center line O in the present reference example .

ここで、この取付孔２３の中心線、すなわち該取付孔２３に取り付けられるクランプネジ２２の雄ネジ部２２Ａの中心線Ｏは、上顎部３Ｂの先端側（押圧部５の押圧面５Ａ）に近づくように傾斜して設けられている。つまり、インサート着脱式切削工具を上面視（切削インサート１１の厚み方向に沿って見た）場合には、図１に示すように、雄ネジ部２２Ａの中心線Ｏが、切削インサート１１の長手方向に対して角度α傾斜している。また、図１のＸ−Ｘ断面（雄ネジ部２２の中心線を含み、切削インサート１１の厚み方向の中心面に垂直に延びる断面）においては、図４に示すように、雄ネジ部２２Ａの中心線Ｏが、前記延長面に垂直な線（切削インサート１１の厚さ方向の中心面と直交する線）に対して角度β傾斜している。 Here, the center line of the attachment hole 23, that is, the center line O of the male screw portion 22A of the clamp screw 22 attached to the attachment hole 23 approaches the distal end side (the pressing surface 5A of the pressing portion 5) of the upper jaw portion 3B. So as to be inclined. That is, when the insert detachable cutting tool is viewed from above (as viewed along the thickness direction of the cutting insert 11), the center line O of the male screw portion 22A is the longitudinal direction of the cutting insert 11 as shown in FIG. Is inclined at an angle α. Further, in the XX cross section (a cross section including the center line of the male screw portion 22 and extending perpendicularly to the center plane in the thickness direction of the cutting insert 11) in FIG. 1, as shown in FIG. The center line O is inclined at an angle β with respect to a line perpendicular to the extended surface (a line perpendicular to the center surface in the thickness direction of the cutting insert 11).

クランプネジ２２の雄ネジ部２２Ａをヘッド部３の上面３Ｅ側に前進するようにネジ孔２４にねじ込んでゆくことにより、頭部２２Ｂの裏面が収容孔２５の平坦面２５Ｃに当接させられる。この状態でさらに雄ネジ部２２Ａをねじ込むことにより、上顎部３Ｂが下顎部３Ｃに近づくように弾性変形させられ、これに伴い、押圧部５の押圧面５Ａが台座４の台座面４Ａに接近するように移動される。 By screwing the male screw portion 22A of the clamp screw 22 into the screw hole 24 so as to advance toward the upper surface 3E side of the head portion 3, the back surface of the head portion 22B is brought into contact with the flat surface 25C of the receiving hole 25. By further screwing the male screw portion 22A in this state, the upper jaw portion 3B is elastically deformed so as to approach the lower jaw portion 3C, and accordingly, the pressing surface 5A of the pressing portion 5 approaches the pedestal surface 4A of the pedestal 4. To be moved.

このようなクランプ機構を備えたインサート着脱式工具において、上記切削インサート１１をホルダ１のインサート取付座６にクランプして取り付けるには、まず、切削インサート１１が、インサート取付座６の台座４に形成された凸Ｖ字状の台座面４Ａに、切削インサート１１のインサート本体１２下面に形成された凹Ｖ字状の着座面１２Ａが嵌合されるように載置される。この状態で、上顎部３Ｂに向けて露呈されているクランプネジ２２の雄ネジ部２２Ａ端部に設けられた係合孔２２Ｃにレンチ等の工具を挿入して回転させることにより、押圧部５を台座４に近づくように上顎部３Ｂを弾性変形させ、切削インサート１１の被押圧面１３Ａと押圧部５の押圧面５Ａとを当接させてクランプする。 In the insert detachable tool having such a clamp mechanism, in order to clamp and attach the cutting insert 11 to the insert mounting seat 6 of the holder 1, first, the cutting insert 11 is formed on the base 4 of the insert mounting seat 6. The concave V-shaped seating surface 12A formed on the lower surface of the insert body 12 of the cutting insert 11 is placed on the convex V-shaped pedestal surface 4A. In this state, by inserting a tool such as a wrench into the engagement hole 22C provided at the end of the male screw 22A of the clamp screw 22 exposed toward the upper jaw 3B and rotating it, the pressing portion 5 is rotated. The upper jaw 3 B is elastically deformed so as to approach the pedestal 4, and the pressed surface 13 A of the cutting insert 11 and the pressing surface 5 A of the pressing portion 5 are brought into contact with each other and clamped.

ここで、本参考例においては、クランプネジ２２の雄ネジ部２２Ａに左ネジを形成しているので、雄ネジ部２２Ａの端部に形成された係合孔２２Ｃを上顎部３Ｂ側から操作する場合には、通常のネジと同様に時計回りに回転させることにより、クランプネジ２２が上顎部３Ｂ側にねじ込まれ、上顎部３Ｂが下顎部３Ｃ側へ近づき、切削インサート１１を固定することができる。 Here, in this reference example , since the left screw is formed in the male screw portion 22A of the clamp screw 22, the engagement hole 22C formed in the end portion of the male screw portion 22A is operated from the upper jaw portion 3B side. In this case, the clamp screw 22 is screwed into the upper jaw portion 3B side by rotating clockwise like a normal screw, and the upper jaw portion 3B approaches the lower jaw portion 3C side, so that the cutting insert 11 can be fixed. .

上記のクランプ機構においては、クランプネジ２２の中心線Ｏが押圧部５の押圧面５Ａに近づくように傾斜して設けられているので、押圧部５を略垂直に台座４へ向けて弾性変形させることができ、押圧部５（上顎部３Ｂ）に曲げモーメントを発生することを抑制できる。よって、切削インサート１１を強固に固定することができ、切削インサート１１の取付剛性を高め、このインサート着脱式工具の加工精度を向上させることができるとともに、切削インサート１１の破損や脱落を防止することができる。 In the above clamping mechanism, the center line O of the clamp screw 22 is provided to be inclined so as to approach the pressing surface 5A of the pressing portion 5, so that the pressing portion 5 is elastically deformed toward the base 4 substantially vertically. It is possible to suppress the generation of a bending moment in the pressing portion 5 (upper jaw portion 3B). Therefore, the cutting insert 11 can be firmly fixed, the mounting rigidity of the cutting insert 11 can be increased, the machining accuracy of the insert detachable tool can be improved, and the cutting insert 11 can be prevented from being damaged or dropped off. Can do.

また、クランプネジ２２が下顎部３Ｃから挿入され、上顎部３Ｂには径の小さな雄ネジ部２２Ａが螺着されているので、上顎部３Ｂに形成されたネジ孔２４を押圧部５のより近傍に設けることができ、押圧部５の押圧面５Ａ（作用点）とクランプネジ２２（力点）との距離を近づけることができる。よって、押圧部５の押圧面５Ａを切削インサート１１の被押圧面１３Ａに確実に当接させて強力に押圧することができるので、一層強固に切削インサート１１を固定することができる。 Further, since the clamp screw 22 is inserted from the lower jaw portion 3C and the male screw portion 22A having a small diameter is screwed to the upper jaw portion 3B, the screw hole 24 formed in the upper jaw portion 3B is placed closer to the pressing portion 5. The distance between the pressing surface 5A (action point) of the pressing part 5 and the clamp screw 22 (power point) can be reduced. Therefore, since the pressing surface 5A of the pressing part 5 can be securely brought into contact with the pressed surface 13A of the cutting insert 11 and pressed strongly, the cutting insert 11 can be fixed more firmly.

なお、この取付孔２３及びクランプネジ２２の中心線Ｏの傾きは、図１に示す上面視における切削インサート１１の長手方向に対しての傾斜角αが５°〜７０°の範囲とされるのが望ましく、また、図４に示す図１のＸ−Ｘ断面におけるスリット３Ａが延びる延長面に垂直な線に対する傾斜角βが２°〜４５°の範囲とされるのが望ましい。これらの傾斜角よりも傾きが小さいと上述の効果を十分に奏功することができなくなるおそれがある一方、逆にこれらの傾斜角よりも傾きが大きいと、上顎部３Ｂの弾性変形による傾きよりも中心線Ｏの傾きが大きくなって、却ってクランプネジ２２の曲がりや上顎部３Ｂの歪みを生じ易くなるおそれがある。 Note that the inclination of the center line O of the mounting hole 23 and the clamp screw 22 is such that the inclination angle α with respect to the longitudinal direction of the cutting insert 11 in the top view shown in FIG. 1 is in the range of 5 ° to 70 °. In addition, it is desirable that the inclination angle β with respect to a line perpendicular to the extended surface extending from the slit 3A in the XX section of FIG. 1 shown in FIG. 4 is in the range of 2 ° to 45 °. If the inclination is smaller than these inclination angles, the above-described effects may not be sufficiently achieved. Conversely, if the inclination is larger than these inclination angles, the inclination due to the elastic deformation of the upper jaw portion 3B is not achieved. There is a possibility that the inclination of the center line O becomes large and the bending of the clamp screw 22 and the distortion of the upper jaw portion 3B tend to occur.

次に、このような参考例を踏まえて、本発明の実施形態について説明する。図５はこの実施形態を示す断面図であり、図１ないし図４に示した参考例と共通する部分には同一の符号を配して説明を省略する。すなわち、上記参考例では、収容孔２５の小径部２５Ａと大径部２５Ｂとの間が該収容孔２５の中心線に垂直な平坦面２５Ｃとされるとともに、クランプネジ２２の頭部２２Ｂが外形厚肉円板状とされて、この平坦面２５Ｃに当接する該頭部２２Ｂの裏面もクランプネジ２２の中心線Ｏに垂直な平面とされ、押圧面５Ａを台座面４Ａに接近するように上顎部３Ｂを弾性変形する際には、この裏面が上記平坦面２５Ｃに密着して当接するようにされていたのに対し、この実施形態においては、収容孔２５の小径部２５Ａと大径部２５Ｂとの間の部分と、クランプネジ２２の頭部２２Ｂのうち上顎部３Ｂ側を向く部分との少なくとも一方が、この上顎部３Ｂ側に向かうに従い漸次縮径するように形成されていることを特徴とする。 Next, based on such a reference example, an embodiment of the present invention will be described. FIG. 5 is a cross-sectional view showing this embodiment, and the same reference numerals are assigned to portions common to the reference example shown in FIGS. 1 to 4 and description thereof is omitted. That is, in the above reference example , the space between the small diameter portion 25A and the large diameter portion 25B of the accommodation hole 25 is a flat surface 25C perpendicular to the center line of the accommodation hole 25, and the head portion 22B of the clamp screw 22 is the outer shape. The back surface of the head portion 22B that is in the shape of a thick disk and is in contact with the flat surface 25C is also a flat surface that is perpendicular to the center line O of the clamp screw 22, and the upper surface so that the pressing surface 5A approaches the base surface 4A. When the portion 3B is elastically deformed, the back surface is in close contact with the flat surface 25C, whereas in this embodiment, the small-diameter portion 25A and the large-diameter portion 25B of the accommodation hole 25 are provided. And at least one of the head 22B of the clamp screw 22 and the portion facing the upper jaw 3B side is formed such that the diameter gradually decreases toward the upper jaw 3B. And

より具体的には、本実施形態では、収容孔２５の小径部２５Ａと大径部２５Ｂとの間の部分は、該収容孔２５の中心線を中心として大径部２５Ｂから小径部２５Ａに向かうに従い漸次縮径する凹円錐面状部２５Ｄとされるとともに、クランプネジ２２の頭部２２Ｂの上顎部３Ｂ側を向く裏面は、該クランプネジ２２の中心線Ｏ上に中心を有する凸曲面状部２２Ｄとされていて、これらの部分の双方が上顎部３Ｂ側に向かうに従いその内外径が漸次縮径する曲面状とされている。すなわち、本実施形態におけるこれらの曲面は、それぞれその中心線に直交する断面が円形をなすとともに、押圧面５Ａを台座面４Ａに接近するように上顎部３Ｂを弾性変形する際に、収容孔２５の小径部２５Ａと大径部２５Ｂとの間のクランプネジ２２の頭部２２Ｂの裏面とで互いに当接する部分が、この当接部分を通る上記中心線Ｏに平行な断面において上顎部３Ｂ側に向け湾曲する曲線（収容孔２５側においては上顎部３Ｂ側に凹む凹曲線。頭部２２Ｂ側においては上顎部３Ｂ側に凸となる凸曲線。）とされている。 More specifically, in this embodiment, the portion between the small diameter portion 25A and the large diameter portion 25B of the accommodation hole 25 is directed from the large diameter portion 25B to the small diameter portion 25A with the center line of the accommodation hole 25 as the center. And the back surface of the clamp screw 22 facing the upper jaw 3B side of the head 22B of the clamp screw 22 is a convex curved surface portion having a center on the center line O of the clamp screw 22. 22D, and both of these portions have a curved surface shape whose inner and outer diameters are gradually reduced toward the upper jaw portion 3B. That is, each of the curved surfaces in the present embodiment has a circular cross section perpendicular to the center line thereof, and when the upper jaw portion 3B is elastically deformed so that the pressing surface 5A approaches the pedestal surface 4A, the receiving holes 25 are provided. The portion of the clamp screw 22 between the small-diameter portion 25A and the large-diameter portion 25B that are in contact with each other on the back surface of the head 22B is on the upper jaw 3B side in a cross section parallel to the center line O passing through the contact portion. It is a curved curve that curves inward (a concave curve that is recessed toward the upper jaw 3B on the accommodation hole 25 side. A convex curve that is convex toward the upper jaw 3B on the head 22B side).

しかるに、上顎部３Ｂを弾性変形させることにより上記接続部分３Ｄを支点として下顎部３Ｃ側に撓ませて切削インサート１１をクランプする本実施形態や参考例、あるいは特許文献１、２に記載のクランプ機構では、この上顎部３Ｂが傾くことによりそのネジ孔２４の中心線が下顎部３Ｃの収容孔２５の中心線に対して傾きを生じ、これによりクランプ時に収容孔２５の小径部２５Ａと大径部２５Ｂとの間の部分に当接させられた頭部２２Ｂとネジ孔２４に螺着された雄ネジ部２２Ａとの間でクランプネジ２２に曲がりや変形が生じるおそれがある一方、上顎部３Ｂにおいてもこのクランプネジ２２の曲がりに伴って上顎部３Ｂが歪んで弾性変形することにより、押圧部５の押圧面５Ａと切削インサート１１の被押圧面１３Ａとが十分に当接されないおそれがある。 However, the clamp mechanism described in the present embodiment or the reference example or the patent documents 1 and 2 in which the upper jaw 3B is elastically deformed to bend toward the lower jaw 3C with the connecting portion 3D as a fulcrum to clamp the cutting insert 11. Then, when the upper jaw portion 3B is inclined, the center line of the screw hole 24 is inclined with respect to the center line of the receiving hole 25 of the lower jaw portion 3C, and thereby the small diameter portion 25A and the large diameter portion of the receiving hole 25 are clamped. While the clamp screw 22 may be bent or deformed between the head 22B brought into contact with the portion between 25B and the male screw portion 22A screwed into the screw hole 24, the upper jaw portion 3B As the clamp screw 22 is bent, the upper jaw portion 3B is distorted and elastically deformed, so that the pressing surface 5A of the pressing portion 5 and the pressed surface 13A of the cutting insert 11 sufficiently contact each other. There may not be.

この点、上記参考例では、小径部２５Ａの内径を雄ネジ部２２Ａの外形よりも僅かに大きくしてクリアランスを持たせ、上記中心線の傾きにクランプネジ２２をある程度追従させることができるようにしているが、略円板状の頭部２２Ｂが収容孔２５の平坦面２５Ｃに当接させられるようにされた参考例では、こうしてクランプネジ２２が傾くと両者が点当たりで当接することとなって安定性が損なわれるおそれがある。 In this respect, in the above reference example , the inner diameter of the small-diameter portion 25A is slightly larger than the outer shape of the male screw portion 22A to provide a clearance so that the clamp screw 22 can follow the inclination of the center line to some extent. However, in the reference example in which the substantially disc-shaped head portion 22B is brought into contact with the flat surface 25C of the receiving hole 25, when the clamp screw 22 is tilted in this way, the two come into contact with each other. Stability may be impaired.

ところが、これに対して、本実施形態では、収容孔２５の小径部２５Ａと大径部２５Ｂとの間が凹円錐面状部２５Ｄとされるとともに、クランプネジ２２の頭部２２Ｂの上顎部３Ｂ側を向く裏面は凸曲面状部２２Ｄとされているので、クランプネジ２２が傾いてもこれら凹円錐面状部２５Ｄと凸曲面状部２２Ｄとは互いに線接触で当接した状態を維持することができる。したがって、本実施形態によれば、上述のように上顎部３Ｂに傾きが生じても、これにクランプネジ２２を追従させて傾動させることができ、クランプネジ２２に曲がりが生じるのを防いでその変形や損傷を防止することができるとともに、上顎部３Ｂが歪んで弾性変形するのも防いで押圧部５の押圧面５Ａと切削インサート１１の被押圧面１３Ａとを確実に当接させることができ、しかもこうしてクランプネジ２２が傾動しても切削インサート１１の取付剛性は十分に確保することができるので、切削インサート１１を確実に保持して円滑な切削を図ることができる。 On the other hand, in this embodiment, the space between the small diameter portion 25A and the large diameter portion 25B of the accommodation hole 25 is a concave conical surface portion 25D, and the upper jaw portion 3B of the head 22B of the clamp screw 22 is used. Since the back surface facing the side is a convex curved surface portion 22D, even if the clamp screw 22 is inclined, the concave conical surface portion 25D and the convex curved surface portion 22D are kept in contact with each other by line contact. Can do. Therefore, according to the present embodiment, even if the upper jaw portion 3B is inclined as described above, the clamp screw 22 can be caused to follow the tilt so that the clamp screw 22 can be prevented from being bent. In addition to preventing deformation and damage, the upper jaw 3B can be prevented from being distorted and elastically deformed, and the pressing surface 5A of the pressing portion 5 and the pressed surface 13A of the cutting insert 11 can be brought into contact with each other with certainty. Moreover, even when the clamp screw 22 is tilted in this manner, the mounting rigidity of the cutting insert 11 can be sufficiently ensured, so that the cutting insert 11 can be securely held and smooth cutting can be achieved.

なお、本実施形態では上述のように収容孔２５の小径部２５Ａと大径部２５Ｂとの間の部分を凹円錐面状部２５Ｄに、クランプネジ２２の頭部２２Ｂ裏面を凸曲面状部２２Ｄに形成して、双方が上顎部３Ｂ側に向けてその径が縮径するように形成されているが、このうちいずれか一方のみをこのように形成して、他方は参考例のままとしても良い。例えば、クランプネジ２２の頭部２２Ｂは参考例と同様に円板状として、収容孔２５側に上記凹円錐面状部２５Ｄや、あるいは上顎部３Ｂ側に凹となる凹球面状部を形成したりしても、クランプネジ２２が傾動したときには上記頭部２２Ｂの裏面と周面との交差稜線部がこれら凹円錐面状部２５Ｄや凹球面状部に線接触することとなるので、安定したクランプを図ることができる。 In the present embodiment, as described above, the portion between the small diameter portion 25A and the large diameter portion 25B of the accommodation hole 25 is a concave conical surface portion 25D, and the back surface of the head 22B of the clamp screw 22 is a convex curved surface portion 22D. Both of them are formed so that the diameter is reduced toward the upper jaw portion 3B side, but only one of them is formed in this way, and the other is left as a reference example. good. For example, the head 22B of the clamp screw 22 is formed in a disk shape like the reference example, and the concave conical surface portion 25D is formed on the accommodation hole 25 side, or the concave spherical surface portion that is concave on the upper jaw portion 3B side is formed. Even when the clamp screw 22 is tilted, the crossed ridge line portion between the back surface and the peripheral surface of the head portion 22B comes into line contact with the concave conical surface portion 25D and the concave spherical surface portion. Clamping can be achieved.

また、逆に収容孔２５では参考例と同様に小径部２５Ａと大径部２５Ｂとの間をその中心線に垂直な平坦面２５Ｃとしておいて、クランプネジ２２の頭部２２Ｂの裏面を凸曲面状部２２Ｄやあるいはクランプネジ２２の中心線Ｏを中心とする凸円錐面状部としたりしてもよく、この場合にはクランプネジ２２が傾動すると、これら凸曲面状部２２Ｄや凸円錐面状部が収容孔２５の小径部２５Ａと平坦面２５Ｃとの交差稜線部に線接触することになってクランプ安定性が確保される。 On the other hand, in the accommodation hole 25, similarly to the reference example , the back surface of the head 22 B of the clamp screw 22 is a convex curved surface with the space between the small diameter portion 25 A and the large diameter portion 25 B as a flat surface 25 C perpendicular to the center line. The convex portion 22D or a convex conical surface portion centered on the center line O of the clamp screw 22 may be used. In this case, when the clamp screw 22 tilts, the convex curved surface portion 22D or the convex conical surface shape is formed. Since the portion comes into line contact with the intersecting ridge line portion between the small diameter portion 25A of the accommodation hole 25 and the flat surface 25C, the clamp stability is ensured.

さらに、このクランプネジ２２の頭部２２Ｂ裏面を凸曲面状部２２Ｄとするとともに、収容孔２５側にはこの凸曲面状部２２Ｄが摺接可能な凹球面状部を形成すれば、クランプネジ２２が傾動してもこれらを面接触に近い状態で当接させることができて、一層のクランプ安定性の向上を図ることが可能となる。また、こうしてクランプネジ２２の頭部２２Ｂ裏面を凸円錐面状部や凸曲面状部２２Ｄとした場合には、収容孔２５の小径部２５Ａと大径部２５Ｂとの間の部分は、該収容孔２５の中心線に沿った断面がその内周側に凸曲しつつ上記上顎部３Ｂ側に向かうに従い縮径する曲面とされる。ただし、これら小径部２５Ａと大径部２５Ｂとの間の部分と頭部２２Ｂ裏面との双方がテーパー角の等しい凹凸円錐面状であると、却ってクランプネジ２２の円滑な傾動が妨げられるおそれがあるので、これらの双方を上顎部３Ｂに向けて径が小さくなるように形成する場合には、このような組み合わせは避ける。 Further, if the back surface of the head 22B of the clamp screw 22 is a convex curved surface portion 22D, and the concave spherical surface portion on which the convex curved surface portion 22D can slide is formed on the receiving hole 25 side, the clamp screw 22 Even if tilted, they can be brought into contact with each other in a state close to surface contact, and the clamp stability can be further improved. When the back surface of the head portion 22B of the clamp screw 22 is thus formed as a convex conical surface portion or a convex curved surface portion 22D, the portion between the small diameter portion 25A and the large diameter portion 25B of the accommodation hole 25 is the accommodation space. while the cross section along the center line of the hole 25 is Totsukyoku on the inner peripheral side thereof Ru is a curved surface whose diameter decreases toward the the upper jaw 3B side. However, if both the portion between the small diameter portion 25A and the large diameter portion 25B and the back surface of the head portion 22B are concave and convex conical surfaces, the tilting of the clamp screw 22 may be hindered. Therefore, such a combination is avoided when both are formed so that the diameter becomes smaller toward the upper jaw portion 3B.

なお、本実施形態においては、切削インサート１１の被押圧面１３Ａ、着座面１２Ａをともに凹Ｖ字状に形成し、インサート取付座６の台座面４Ａ、押圧面５Ａをともに凸Ｖ字状に形成したもので説明したが、これに限定されることはなく、切削インサート１１の被押圧面１３Ａ、着座面１２Ａのうち、少なくとも一方を凸Ｖ字状に形成し、これに係合するようにインサート取付座６の押圧面５Ａ、台座面４Ａを形成しても良い。
また、ホルダ１の軸線Ｌと切削インサート１１の長手方向とが平行に位置するインサート着脱式工具により説明したが、これに限定されることはなく、例えば、切削インサート１１の長手方向とホルダ１の軸線Ｌと直交するように配置されたインサート着脱式工具であっても良い。
さらに、クランプネジ２２が上述のように傾斜して設けられていれば、雄ネジ部２２Ａが他方の顎部（下顎部３Ｃ）にねじ込まれるとともに、頭部２２Ｂが一方の顎部（上顎部３Ｂ）に設けられた収容孔に収容され、押圧部５を弾性変形させるものであっても良い。 In this embodiment, the pressed surface 13A and the seating surface 12A of the cutting insert 11 are both formed in a concave V shape, and the pedestal surface 4A and the pressing surface 5A of the insert mounting seat 6 are both formed in a convex V shape. However, the present invention is not limited to this, and at least one of the pressed surface 13A and the seating surface 12A of the cutting insert 11 is formed in a convex V shape and is inserted into the insert. The pressing surface 5A and the pedestal surface 4A of the mounting seat 6 may be formed.
In addition, the insert detachable tool in which the axis L of the holder 1 and the longitudinal direction of the cutting insert 11 are parallel to each other has been described. However, the present invention is not limited to this, and for example, the longitudinal direction of the cutting insert 11 and the holder 1 An insert detachable tool arranged so as to be orthogonal to the axis L may be used.
Further, if the clamp screw 22 is inclined as described above, the male screw portion 22A is screwed into the other jaw portion (lower jaw portion 3C), and the head portion 22B is one jaw portion (upper jaw portion 3B). ) And may be elastically deformed by the pressing portion 5.

本発明の実施形態を説明する上での参考例及び実施形態であるインサートのクランプ機構を適用したインサート着脱式切削工具の上面図である。Is a top view of the insert-indexable tool according to the clamping mechanism of the insert is a reference example and embodiments of the embodiments in describing the present invention. 本発明の実施形態を説明する上での参考例及び実施形態であるインサートのクランプ機構を適用したインサート着脱式切削工具の側面図である。Is a side view of the insert-indexable tool according to the clamping mechanism of the insert is a reference example and embodiments of the embodiments in describing the present invention. 本発明の実施形態を説明する上での参考例及び実施形態であるインサートのクランプ機構を適用したインサート着脱式切削工具の正面図である。Is a front view of the insert-indexable tool according to the clamping mechanism of the insert is a reference example and embodiments of the embodiments in describing the present invention. 参考例における図１のＸ−Ｘ断面を示す断面図である。It is sectional drawing which shows the XX cross section of FIG. 1 in a reference example . 実施形態における図１のＸ−Ｘ断面を示す断面図である。It is sectional drawing which shows the XX cross section of FIG. 1 in embodiment .

Explanation of symbols

１ホルダ
３Ｂ上顎部（一方の顎部）
３Ｃ下顎部（他方の顎部）
４台座
４Ａ台座面
５押圧部
５Ａ押圧面
６インサート取付座
１１切削インサート
１２Ａ着座面
１３Ａ被押圧面
２２クランプネジ
２２Ａ雄ネジ部
２２Ｂ頭部
２５収容孔
２５Ａ小径部
２５Ｂ大径部 1 Holder 3B Upper jaw (one jaw)
3C Lower jaw (the other jaw)
4 pedestal 4A pedestal surface 5 pressing portion 5A pressing surface 6 insert mounting seat 11 cutting insert 12A seating surface 13A pressed surface 22 clamp screw 22A male screw portion 22B head 25 receiving hole 25A small diameter portion 25B large diameter portion

Claims

Cutting provided with a pressed surface and a seating surface that are in contact with the pressing surface and the pedestal surface, respectively, on an insert mounting seat that is formed at the tip of the holder and has a pressing surface and a pedestal surface that extend opposite to each other. A clamping mechanism of a cutting insert that clamps by inserting and inserting the insert,
A pair of jaws having one jaw and the other jaw are formed at the tip of the holder,
The other jaw portion is provided with a pedestal having the pedestal surface, and the one jaw portion is provided with a pressing portion having the pressing surface,
A clamp screw that elastically deforms the pressing portion and approaches the pedestal in the abutting direction on the pair of jaw portions, with respect to the insert mounting seat, the width direction side of the pressing surface and the pedestal surface The clamp screw is provided so as to be inclined toward the pressing surface of the pressing portion as it goes toward the one jaw side,
The clamp screw has a male screw portion and a head having a larger diameter than the male screw portion, and the one jaw portion is provided with a female screw portion to which the male screw portion is screwed. ,
The other jaw portion has a small-diameter portion that is smaller in diameter than the head portion that opens toward the one jaw portion side and into which the male screw portion can be loosely inserted, and an opening opposite to the one jaw portion. And a housing hole having a large diameter portion capable of housing the head,
At least one of the portion between the small-diameter portion and the large-diameter portion of the accommodation hole and the portion facing the one jaw portion side of the head portion, both of these portions have the same taper angle Except for the conical surface shape, the diameter is gradually reduced toward the one jaw side ,
The portion of the head of the clamp screw that faces the one jaw side is a convex conical surface portion or a convex curved surface portion, and the portion between the small diameter portion and the large diameter portion of the accommodation hole is A clamping mechanism for a cutting insert , wherein a cross section along the center line of the accommodation hole has a curved surface shape that is curved toward the inner side while being reduced in diameter toward the one jaw side .

An angle formed by a surface including a center line of the male screw portion of the clamp screw and extending perpendicularly to a center surface in the thickness direction of the insert and a center surface in the width direction of the insert is in a range of 5 ° to 70 °. The clamping mechanism for a cutting insert according to claim 1, wherein

A center line of the male screw portion of the clamp screw and a center line of the male screw portion of the clamp screw and a center of the insert in the thickness direction in a cross section including a center line of the male screw portion of the clamp screw and extending perpendicularly to a central plane in the thickness direction of the insert 3. The cutting insert clamping mechanism according to claim 1, wherein an angle formed by a line perpendicular to the surface is in a range of 2 ° to 45 °. 4.