JP2017052024A - Cutting insert for grooving tool and cutting edge replaceable grooving tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To be capable of preventing a cutting insert for a grooving tool from dropping out of an insert attachment seat when the tool is used, as well as improving operability in attachment by preventing the cutting insert for grooving from dropping when the cutting insert for grooving is attached to the insert attachment seat.SOLUTION: A cutting insert 20 for grooving having a rod-like shape comprises: a cutting part 27 formed at one end part of both end parts along an extension direction L of the rod-like shape; and a part to be clamped 28 formed at a position other than the one end along the extension direction L. The part to be clamped 28 comprises: an upper surface 24 facing the same direction as that a rake face 22 faces; and a lower surface 25 facing a direction opposite to that the upper surface 24 faces. The upper surface 24 comprises: a guide part 24a formed to be in parallel with the lower surface 25; and a part to be pressed 24b formed to be arranged adjacent to one end part side of the extension direction L of the guide part 24a, and inclined in respect to the lower surface 25 to become closer to the lower surface 25 as getting closer to the one end part side.SELECTED DRAWING: Figure 5

Description

  TECHNICAL FIELD The present invention relates to a grooving cutting insert for subjecting a work material to grooving or parting-off processing and the like, and a blade-tip-replaceable grooving tool using the same.

  Conventionally, a work piece made of a metal material or the like that has a columnar shape or a cylindrical shape is rotated around its axis, and is used for grooving on the outer peripheral surface, inner peripheral surface, and end surface facing the axial direction of the work material. 2. Description of the Related Art A cutting edge exchange type grooving tool that performs cutting with a cutting blade of a cutting insert and performs grooving, parting off, etc. (hereinafter sometimes simply referred to as grooving) is known (for example, Patent Document 1 below) 2).

  In this type of cutting edge-replaceable grooving tool, a grooving cutting insert is detachably mounted on an insert mounting seat formed at the tip of the tool body and extending in a slit shape. The insert mounting seat has a top wall that contacts the upper surface of the grooving cutting insert and a bottom wall that contacts the lower surface of the grooving cutting insert. One end portion (insert insertion port) of both end portions along the extending direction of the insert mounting seat is open to the end surface (surface facing the grooving direction) of the tip portion of the tool body.

  When the grooving cutting insert is mounted on the insert mounting seat, the grooving cutting insert is inserted from the one end along the extending direction of the insert mounting seat. In a state in which the grooving cutting insert is mounted on the insert mounting seat, the cutting edge of the grooving cutting insert projects from the one end portion of the insert mounting seat.

  For example, in the following Patent Document 1, a pair of pressed portions inclined with respect to the lower surface of the grooving cutting insert is formed on the upper surface of the grooving cutting insert. These pressed parts are brought into contact with the top wall of the insert mounting seat, thereby preventing the cutting insert for grooving from slipping out of the insert mounting seat.

  As used herein, “removal” means that the grooving cutting insert mounted on the insert mounting seat moves unintentionally along the extending direction of the insert mounting seat, and one end of the insert mounting seat. It means to escape from the outside. Specifically, for example, when the tool is separated from the work material after grooving, when the cutting edge of the grooving cutting insert located in the machined groove comes into contact with the inner wall of the groove (hook) In such a case, such “out” may occur.

Japanese Patent No. 3246220 International Publication No. 2015/020274

However, the conventional cutting edge exchange type grooving tool has the following problems.
That is, when installing a grooving cutting insert on the insert mounting seat, when inserting the grooving cutting insert from one end (insert insertion port) along the extending direction of the insert mounting seat, The cutting insert sometimes unintentionally dropped from the insert mounting seat. For this reason, there was room for improvement in improving the mounting operability of the grooving cutting insert to the insert mounting seat.

  The present invention has been made in view of such circumstances, and when a tool is used, the cutting insert for grooving can be prevented from coming out of the insert mounting seat, and the cutting insert for grooving is inserted into the insert mounting seat. It is an object of the present invention to provide a grooving cutting insert that can prevent the grooving cutting insert from falling off and improve the mounting operability, and a blade replacement type grooving tool using the same.

In order to solve such problems and achieve the above object, the present invention proposes the following means.
That is, the present invention has a rod shape, a blade portion is formed at one end of both end portions along the extending direction, and a clamped portion is formed at a portion other than the one end portion along the extending direction. A cutting insert for grooving, wherein the blade part has a rake face, a flank face, and a cutting edge formed at a cross ridge line part of the rake face and the flank face, and the clamped part Has a top surface facing the same direction as the rake face, and a bottom surface facing the opposite side of the top surface, the guide surface formed on the top surface so as to be parallel to the bottom surface, A pressed portion that is arranged adjacent to one end side in the extending direction of the guide portion and is inclined with respect to the lower surface so as to approach the lower surface toward the one end portion; Is provided.
Further, the present invention provides an insert holding plate portion provided in the tool body, and both end portions extending through the insert holding plate portion in the thickness direction of the insert holding plate portion and extending in a slit shape along the extending direction. An insert mounting seat whose one end is open to the end face of the insert holding plate portion, and a grooving that is detachably mounted on the insert mounting seat with a cutting edge protruding from the one end of the insert mounting seat. A cutting edge replacement grooving tool, wherein the grooving cutting insert described above is used as the grooving cutting insert, and the insert mounting seat has a top wall that comes into contact with the upper surface; And a bottom wall contacting the lower surface.

  In the grooving cutting insert and the cutting edge replaceable grooving tool of the present invention, when the grooving cutting insert is mounted on the insert mounting seat, the lower surface of the grooving cutting insert is located on the bottom wall of the insert mounting seat. Abut. In addition, the guide portion of the upper surface of the grooving cutting insert comes into contact with the top wall of the insert mounting seat, and extends along the extending direction of the insert mounting seat (the extending direction of the grooving cutting insert). When the grooving cutting insert is inserted into the insert mounting seat and the grooving cutting insert has been inserted, the top surface of the grooving cutting insert is covered with the top wall of the insert mounting seat. The pressing part is brought into contact.

  Specifically, the guide portion on the upper surface of the grooving cutting insert and the lower surface of the grooving cutting insert are formed so as to be parallel to each other. When the grooving cutting insert is inserted along the extending direction from the insertion slot), the grooving cutting insert is stably supported from above and below between the top wall and the bottom wall of the insert mounting seat. Continue to be.

  That is, while the grooving cutting insert is inserted into the insert mounting seat, the bottom wall of the insert mounting seat continues to be in sliding contact with the lower surface of the grooving cutting insert, and the top wall of the insert mounting seat is grooved. Continue sliding contact with the guide on the top surface of the insert. As a result, the grooving cutting insert is stably guided from above and below until it is inserted into the insert mounting seat, and the grooving cutting insert is prevented from falling off the insert mounting seat.

  In addition, in the state where the grooving cutting insert has been inserted into the insert mounting seat, the pressed surface located on the one end side (blade part side) in the extending direction from the guide part on the upper surface of the grooving cutting insert. The portion is brought into contact with the top wall of the insert mounting seat. Since the pressed portion is inclined so as to approach the lower surface toward the one end portion on the upper surface of the grooving cutting insert, the pressed portion is brought into contact with the top wall of the insert mounting seat ( By being pressed, the cutting insert for grooving with respect to the insert mounting seat is prevented from coming out.

In addition, in order to stably obtain the effects of the above-described guide portion and pressed portion, the following configuration is adopted in the insert holding plate portion where the insert mounting seat is formed at the tip portion of the tool body. It is preferable to do.
That is, for example, when the grooving cutting insert is inserted into the insert mounting seat, the insert holding plate portion is elastically deformed in advance so that the top wall and the bottom wall of the insert mounting seat are moved away from each other in advance. When the insertion cutting insert has been inserted, the elastic deformation of the insert holding plate portion is released and restored, and the top wall of the insert mounting seat is configured to abut against the pressed portion. Specifically, with the insert holding plate portion elastically deformed, the top wall and the bottom wall of the insert mounting seat are arranged in parallel to each other, and the top surface of the grooving cutting insert with respect to the top wall and the bottom wall. The grooving cutting insert may be inserted into the insert mounting seat while the guide portion and the lower surface are in sliding contact with each other.

  Alternatively, for example, by providing a clamp screw in the tool body and screwing (tightening) the clamp screw, the insert holding plate portion is elastically deformed so that the top wall and the bottom wall of the insert mounting seat move closer to each other. The top wall of the insert mounting seat may be configured to abut against the pressed portion of the grooving cutting insert. Specifically, the top wall and the bottom wall of the insert mounting seat are arranged in parallel with each other in a state where the insert holding plate portion is not elastically deformed, and the top surface of the grooving cutting insert with respect to these top wall and bottom wall. The grooving cutting insert is inserted into the insert mounting seat while sliding the guide portion and the lower surface of the insert mounting seat. Then, when the grooving cutting insert has been inserted, a clamp screw is screwed in, the insert holding plate portion is elastically deformed, and the pressed portion of the cutting insert is pressed by the top wall of the insert mounting seat.

  As described above, according to the present invention, when a tool is used, it is possible to prevent the grooving cutting insert from coming out of the insert mounting seat, and when the grooving cutting insert is mounted on the insert mounting seat, the groove is inserted. The mounting operability can be improved by preventing the insert cutting insert from falling off.

  Moreover, the cutting insert for grooving of this invention WHEREIN: It is preferable that the length of the said to-be-pressed part along the said extension direction is longer than the length of the said guide part along the said extension direction.

  In this case, when the grooving cutting insert is inserted into the insert mounting seat, the grooving cutting insert can be prevented from falling off by the action of the above-described guide portion. Then, in the state where the grooving cutting insert has been attached to the insert mounting seat, the top wall of the insert mounting seat is placed against the pressed part whose length along the extending direction of the grooving cutting insert is increased. Can be contacted over a wide range. Accordingly, it is possible to effectively prevent the grooving cutting insert from slipping out and to improve the clamp stability of the grooving cutting insert.

  Moreover, the cutting insert for grooving of this invention WHEREIN: It is preferable that the length of the said to-be-pressed part along the said extending direction is 2-5 times the length of the said guide part along the said extending direction.

  In this case, when inserting the grooving cutting insert into the insert mounting seat, it is possible to prevent the grooving cutting insert from falling off more reliably, and when the grooving cutting insert is mounted on the insert mounting seat, The effect of preventing the cutting insert from slipping out and the effect of improving the clamp stability of the grooving cutting insert can be made particularly remarkable.

Specifically, since the length of the pressed portion along the extending direction of the grooving cutting insert is more than twice the length of the guide portion along the extending direction, the pressed portion of the grooving cutting insert And a sufficient contact area with the top wall of the insert mounting seat. Accordingly, it is possible to reliably prevent the grooving cutting insert from coming out, and the clamp stability of the grooving cutting insert is significantly improved.
Moreover, since the length of the pressed part along the extending direction of the cutting insert for grooving is 5 times or less of the length of the guide part along the extending direction, the length of the pressed part is sufficiently secured. However, it is possible to suppress the length of the guide portion from becoming too short and stabilize the action of the guide portion. Accordingly, when the grooving cutting insert is mounted on the insert mounting seat, the grooving cutting insert can be reliably prevented from falling off.

  Further, in the grooving cutting insert of the present invention, when viewed from the extending direction of the grooving cutting insert and the thickness direction perpendicular to the vertical direction connecting the upper surface and the lower surface, The angle formed between the lower surface and the lower surface is preferably 1 to 10 °.

  In this case, the effect of preventing the grooving cutting insert from slipping out of the insert mounting seat and the effect of improving the clamp stability can be made more remarkable by the action of the pressed portion described above. .

Specifically, as viewed from the thickness direction of the grooving cutting insert, the angle formed between the pressed portion and the lower surface is 1 ° or more. On the other hand, when the top wall of the insert mounting seat abuts, the effect of preventing the above-described withdrawal and the effect of improving the clamp stability can be reliably obtained.
In addition, since the angle formed between the pressed part and the bottom surface is 10 ° or less when viewed from the thickness direction of the grooving cutting insert, this grooving cutting insert is mounted on the insert mounting seat. Then, the top wall of the insert mounting seat can be reliably brought into contact with the pressed portion of the grooving cutting insert by elastically deforming or restoring the insert holding plate portion. Therefore, the above-described operational effects of the present invention can be obtained stably.

  In the grooving cutting insert of the present invention, it is preferable that at least one of the upper surface and the lower surface is formed in a V shape in a cross-sectional view perpendicular to the extending direction.

  In this case, the movement of the grooving cutting insert with respect to the insert mounting seat in the thickness direction (the slit penetration direction of the insert mounting seat) is restricted, and the above-described operational effects of the present invention become more stable.

  According to the grooving cutting insert and the cutting edge replaceable grooving tool of the present invention, when the tool is used, the grooving cutting insert can be prevented from coming out of the insert mounting seat, and the grooving cutting insert is inserted into the insert mounting seat. When mounting, it is possible to improve the mounting operability by preventing the grooving cutting insert from falling off.

It is a figure explaining the grooving process using the blade-tip-exchange-type grooving tool which concerns on 1st Embodiment of this invention. It is a figure explaining the grooving process using the blade-tip-exchange-type grooving tool which concerns on 1st Embodiment of this invention. It is a perspective view which shows the blade-tip-exchange-type grooving tool which concerns on 1st Embodiment of this invention. It is a side view which shows a blade-tip-exchange-type grooving tool. It is a figure which expands and shows the principal part of the blade-tip-exchange-type grooving tool of FIG. It is (a) front view and (b) top view which show a blade-tip-exchange-type grooving tool. It is a perspective view which shows the cutting insert for grooving of a blade-tip-exchange-type grooving tool. It is the (a) side view, (b) top view, (c) front view which shows the cutting insert for grooving. FIG. 10A is a side view showing a cutting insert for grooving, and FIG. 9B is a sectional view taken along line BB in FIG. It is a figure explaining the procedure which attaches and detaches the cutting insert for grooving to an insert mounting seat. It is a figure explaining the procedure which attaches and detaches the cutting insert for grooving to an insert mounting seat. It is a figure explaining the procedure which attaches and detaches the cutting insert for grooving to an insert mounting seat. It is a perspective view which shows the blade-tip-exchange-type grooving tool which concerns on 2nd Embodiment of this invention. It is a figure explaining the procedure which attaches and detaches the cutting insert for grooving to an insert mounting seat. It is a figure explaining the grooving process using the blade-tip-exchange-type grooving tool which concerns on 3rd Embodiment of this invention. It is a perspective view which shows the blade-tip-exchange-type grooving tool which concerns on 3rd Embodiment of this invention.

<First Embodiment>
Hereinafter, the cutting edge exchange-type grooving tool 10 and the grooving cutting insert 20 according to the first embodiment of the present invention will be described with reference to FIGS.

[Schematic configuration of cutting edge exchange grooving tool]
As shown in FIGS. 1 and 2, the blade-tip-replaceable grooving tool 10 according to the present embodiment is formed on a work material W made of, for example, a metal material and having a cylindrical shape or a cylindrical shape. A turning process (turning process) such as a cutting process is performed. Specifically, the work material W is rotated around the axis A in the work material rotation direction R, and the cutting edge-replaceable grooving tool 10 is in the radial direction perpendicular to the axis A with respect to the work material W. Is moved toward the inside (the direction of the white arrow shown in FIGS. 2A and 2B) and cut into the outer peripheral surface of the work material W with the cutting edge 21 of the cutting insert 20 for grooving. Apply grooving.

As shown in FIG. 3 to FIG. 6, the blade replacement type grooving tool 10 is made of a tool body 1 made of steel, cemented carbide, or the like, and is detachably mounted on the insert mounting seat 4 of the tool body 1. And a grooving cutting insert 20.
In this embodiment, the tool main body 1 has a rectangular plate shape, and an insert holding plate portion 2 is provided at an end portion (tip portion) in a direction in which the tool main body 1 extends. In the example of the present embodiment, the insert holding plate portion 2 of the tool body 1 and the portions other than the insert holding plate portion 2 are formed in a plate shape having substantially the same thickness, and the entire tool body 1 has a flat plate shape. There is no.

The insert mounting seat 4 extends through the insert holding plate portion 2 in the thickness direction T of the insert holding plate portion 2 and extends in a slit shape. That is, the insert mounting seat 4 is open on both side surfaces (front and back surfaces) facing the thickness direction T of the insert holding plate portion 2. Moreover, one end part (insert insertion port) of both ends along the extending direction L of the insert mounting seat 4 opens to the end face of the insert holding plate part 2 (the tip face of the tool body 1 in this embodiment). Yes.
The grooving cutting insert 20 is mounted on the insert mounting seat 4 with the cutting edge 21 protruding from one end of the insert mounting seat 4.

  Although not shown in particular, the tool body 1 can be attached to and detached from a machine tool such as an NC lathe via a clamp member that clamps the tool body 1 from both sides of the tool height direction HT (that is, the vertical direction). Installed.

[Definition of direction (direction) used in this specification]
In this specification, the direction in which the insert holding plate 2 provided at the tip of the tool body 1 is projected from a portion other than the insert holding plate 2 (a portion other than the tip of the tool body 1) is projected. It is called direction P. The protruding direction P is set to the same direction as the “grooving direction” in which the cutting edge replaceable grooving tool 10 is moved with respect to the work material W during grooving. In the example of this embodiment, in the top view of the tool body 1 when the rake face 22 of the grooving cutting insert 20 is viewed from the front, the protruding direction P is the tool axis of the tool body 1 (the extending direction of the tool body 1, The tool body 1 extends along the longitudinal direction of the tool body 1.

The direction along the thickness of the insert holding plate portion 2 is referred to as a thickness direction T.
Moreover, the direction orthogonal to the extending direction (protrusion direction P) and the thickness direction T of the tool body 1 is referred to as a tool height direction HT. Of the tool height direction HT, during grooving, the direction in which the rake face 22 of the cutting edge 21 of the grooving cutting insert 20 faces (the upper side in FIG. 5) is referred to as the upper direction (the tool upper direction). The opposite side (the lower side in FIG. 5) to the facing direction is referred to as the lower side (lower tool).

Moreover, the direction (extending direction L) in which the insert mounting seat 4 formed on the insert holding plate portion 2 extends is different from the protruding direction P and the extending direction of the tool body 1 described above. As shown in FIG. 5, when viewed from the thickness direction T of the insert holding plate portion 2, the extending direction L of the insert mounting seat 4 is not parallel to the protruding direction P of the insert holding plate portion 2 but protrudes. As it goes in the direction P, it is gradually inclined upward in the tool height direction HT.
In the description of the insert mounting seat 4 to be described later, in FIG. 5, the direction from the rear wall 4c along the extending direction L toward the opening (insert insertion port) of the insert mounting seat 4 is one end portion in the extending direction L. The direction from the opening along the extending direction L toward the rear wall 4c may be referred to as the other end side of the extending direction L.

Further, the grooving cutting insert 20 has a rod shape, and its extending direction is the same as the extending direction L of the insert mounting seat 4 to which the grooving cutting insert 20 is mounted. Therefore, in this specification, the extending direction of the grooving cutting insert 20 is represented by the same reference symbol L as the extending direction L of the insert mounting seat 4.
In the description of the grooving cutting insert 20 described later, in FIG. 5, the direction from the clamped portion 28 along the extending direction L toward the blade portion 27 side is referred to as one end portion side of the extending direction L. The direction from the blade portion 27 along the existing direction L toward the clamped portion 28 may be referred to as the other end portion side of the extending direction L.
The thickness direction of the grooving cutting insert 20 is the same as the thickness direction T of the insert holding plate portion 2. Therefore, in the present specification, the thickness direction of the grooving cutting insert 20 is denoted by the same reference symbol T as the thickness direction T of the insert holding plate portion 2.

The direction perpendicular to the extending direction L and the thickness direction T of the grooving cutting insert 20 is referred to as an insert height direction HI. Of the insert height direction HI, the direction in which the rake face 22 of the grooving cutting insert 20 faces (the upper side in FIG. 7) is referred to as the upper side (upper insert), and the opposite side to the direction in which the rake face 22 faces (see FIG. 7). The lower side in FIG. 4 is referred to as the lower side (lower insert).
As shown in FIG. 5, the insert height direction HI of the grooving cutting insert 20 and the tool height direction HT of the tool body 1 have different directions.

(Tool body)
As shown in FIGS. 3 and 4, the tool body 1 is 180 ° rotationally symmetric with respect to a tool center line C extending along the thickness direction T through the center in the extending direction and the center in the tool height direction HT. Is formed. Further, the insert mounting seats 4 are respectively disposed at both end portions in the extending direction of the tool body 1. In the example of the present embodiment, the pair of insert mounting seats 4 are arranged so as to be 180 ° rotationally symmetric about the tool center line C passing through the centers of both side surfaces facing the thickness direction T of the tool body 1. Are formed in the same shape.
The insert mounting seats 4 may have different shapes and may be a tool body 1 on which a plurality of types of grooving cutting inserts 20 can be mounted. Further, only one insert mounting seat 4 may be provided in the tool body 1.

  As shown in FIGS. 3, 4, and 6 (a), the upper surface and the lower surface of the tool body 1 facing the tool height direction HT extend along the extending direction of the tool body 1. Of the upper and lower surfaces of the tool body 1, at least the portions other than the insert holding plate portion 2 have a convex V-shaped cross section perpendicular to the extending direction of the tool body 1.

[Insert holding plate]
3-5, the insert holding | maintenance board part 2 is provided with the upper jaw part 5 and the lower jaw part 6 which oppose the tool height direction HT. The upper jaw portion 5 and the lower jaw portion 6 are separated from each other in the tool height direction HT, and the insert mounting seat 4 is formed in a gap provided therebetween.
Further, in the gap of the tool body 1, the portion located on the side opposite to the projecting direction P from the insert mounting seat 4 (inner side of the tool along the extending direction of the tool body 1, the tool center side) An opening / closing operation slit (slit) 7 communicating with the insert mounting seat 4 is formed. The opening / closing operation slit 7 penetrates the insert holding plate portion 2 in the thickness direction T, and extends from the communicating portion with the insert mounting seat 4 toward the side opposite to the protruding direction P.

[Upper jaw, lower jaw, coolant hole]
The upper jaw 5 has a substantially triangular plate shape at the tip in the protruding direction P. As for the lower jaw part 6, the front-end | tip part of the protrusion direction P has comprised the substantially square plate shape. An insert mounting seat 4 is disposed between the distal end portion of the upper jaw portion 5 in the projecting direction P and the distal end portion of the lower jaw portion 6 in the projecting direction P. An opening / closing operation slit 7 is disposed between a portion of the upper jaw portion 5 other than the distal end portion and a portion of the lower jaw portion 6 other than the distal end portion.

The length (height) along the tool height direction HT of the upper jaw part 5 is made smaller than the length along the tool height direction HT of the lower jaw part 6. The height at the distal end portion of the upper jaw portion 5 in the protruding direction P decreases as it goes in the protruding direction P. The height at the distal end portion of the lower jaw portion 6 in the protruding direction P increases as it goes in the protruding direction P.
The length (projection length) along the projecting direction P of the upper jaw 5 is made shorter than the length along the projecting direction P of the lower jaw 6. That is, the tip of the lower jaw 6 in the protruding direction P is arranged so as to protrude in the protruding direction P from the tip of the upper jaw 5 in the protruding direction P.

  The upper jaw 5 is formed to be elastically deformable. Specifically, the upper jaw part 5 is elastically deformed and restored to be deformed, so that the end part of the upper jaw part 5 opposite to the protruding direction P (specifically, the opposite side of the protruding direction P of the opening / closing operation slit 7) It is possible to rotate about the tool height direction HT around a portion located above the end portion, and to approach and separate from the lower jaw 6.

  As shown in FIGS. 3 and 6 (a) and 6 (b), in the example of the present embodiment, the end face (protrusion) disposed close to the rake face 22 of the cutting edge 21 of the cutting insert 20 for grooving in the upper jaw portion 5. The coolant hole 11 is opened in the direction P and the inclined surface facing upward. Further, a coolant hole 12 is opened at an end surface (an end surface facing the protruding direction P) disposed close to the flank 23 of the cutting edge 21 of the cutting insert 20 for grooving in the lower jaw 6.

These coolant holes 11 and 12 are connected to coolant supply means of a machine tool (not shown) through the inside of the tool body 1. A coolant (oil-based or water-soluble cutting fluid) flows through the coolant holes 11 and 12. Of these coolant holes 11, 12, the coolant flowing through the coolant hole 11 that opens toward the rake face 22 is ejected from the opening of the coolant hole 11, thereby passing over the rake face 22 and a cutting edge. 21 is supplied to the vicinity. Further, the coolant flowing through the coolant hole 12 that opens toward the flank 23 is supplied from the opening of the coolant hole 12 to the vicinity of the cutting edge 21 through the flank 23.
3 and 4 is a coolant supply port that is connected to the coolant supply means and communicates with the coolant holes 11 and 12. In the example shown in the figure, the coolant supply port 19 is open on the side surface facing the thickness direction T of the tool body 1.

(Insert mounting seat)
3 to 6, the insert mounting seat 4 is disposed in an upper portion of the insert holding plate portion 2 in the tool height direction HT. The insert mounting seat 4 is opened on both side surfaces facing the thickness direction T of the insert holding plate portion 2, and one end portion of the both ends along the extending direction L of the insert mounting seat 4 (the insert is inserted). The portion to be inserted is opened at the tip surface (end surface facing the protruding direction P) of the insert holding plate portion 2.
As shown in FIG. 5, a rear wall 4 c and a dull portion 4 d to be described later are disposed at the other end portion (the portion against which the insert is abutted) among both end portions along the extending direction L of the insert mounting seat 4. ing. An opening / closing operation slit 7 is connected to the other end of the insert mounting seat 4.

  The insert mounting seat 4 is inclined and extended upward in the tool height direction HT as it goes in the protruding direction P. In FIG. 5, among the acute angles and obtuse angles formed between the extending direction L of the insert mounting seat 4 and the protruding direction P, the acute angle α is, for example, 15 to 30 °.

  The insert mounting seat 4 is formed on the top wall 4 a that contacts the upper surface 24 of the grooving cutting insert 20, the bottom wall 4 b that contacts the lower surface 25 of the grooving cutting insert 20, and the back surface 26 of the grooving cutting insert 20. It has the rear wall 4c which contact | abuts in any one among the inclined wall-shaped back surface part 26a and the vertical wall-shaped back surface part 26b mentioned later. As shown in FIG. 5, in the example of this embodiment, the contact length (contact area) of each wall 4a, 4b, 4c of the insert mounting seat 4 with respect to the grooving cutting insert 20 is the bottom wall 4b, the top wall. 4a and the rear wall 4c are made smaller in this order. That is, the contact length of the bottom wall 4b is the largest, the contact length of the rear wall 4c is the smallest, and the contact length of the top wall 4a is the size between them.

The top wall 4a and the bottom wall 4b of the insert mounting seat 4 are gradually inclined upward toward the protruding direction P. The bottom wall 4 b of the insert mounting seat 4 extends along the extending direction L of the insert mounting seat 4.
As shown in FIG. 5, with the grooving cutting insert 20 mounted on the insert mounting seat 4, the top wall 4 a of the insert mounting seat 4 extends along the extending direction L of the insert mounting seat 4. It is inclined with respect to the bottom wall 4b so as to gradually approach the bottom wall 4b as it goes from the end (rear wall 4c) toward the one end (insert insertion port). That is, in FIG. 5, the top wall 4 a and the bottom wall 4 b are not parallel to each other, but gradually approach each other as they go toward one end in the extending direction L. Of the acute and obtuse angles formed between the top wall 4a and the bottom wall 4b, the acute angle θ is 1 to 10 °, preferably about 2 °.

However, as described above, the upper jaw portion 5 can be elastically deformed, and when the grooving cutting insert 20 is inserted into the insert mounting seat 4, the upper jaw portion 5 is elastically deformed in advance, so that the angle θ is set. The angle is substantially 0 ° (the top wall 4a and the bottom wall 4b are parallel).
A method for attaching and detaching the grooving cutting insert 20 to the insert mounting seat 4 will be described later.

  The rear wall 4c of the insert mounting seat 4 is gradually inclined toward the protruding direction P as it goes upward in the tool height direction HT. In the example of this embodiment, the rear wall 4c of the insert mounting seat 4 is an inclined wall-shaped back surface portion 26a among the inclined wall-shaped back surface portion 26a and the vertical wall-shaped back surface portion 26b provided on the back surface 26 of the grooving cutting insert 20. It is made to contact. As shown in FIG. 5, when the insert holding plate portion 2 is viewed from the thickness direction T, an acute angle or an obtuse angle formed between the bottom wall 4 b and the rear wall 4 c of the insert mounting seat 4. β is, for example, 40 to 70 °.

Between the bottom wall 4b and the rear wall 4c of the insert mounting seat 4, a concave dull portion 4d is formed. Further, the top wall 4 a and the rear wall 4 c of the insert mounting seat 4 are divided by an opening / closing operation slit 7. In other words, the insert mounting seat 4 and the opening / closing operation slit 7 communicate with each other through the space between the top wall 4a and the rear wall 4c of the insert mounting seat 4.
Among the insert mounting seats 4, the top wall 4 a is formed on the upper jaw 5, and the bottom wall 4 b, the rear wall 4 c and the thinning portion 4 d are formed on the lower jaw 6.

  Although not shown in particular, the top wall 4a of the insert mounting seat 4 is formed in a convex V-shape that is convex toward the bottom wall 4b in a cross-sectional view perpendicular to the extending direction L of the insert mounting seat 4. Has been. The bottom wall 4 b of the insert mounting seat 4 is formed in a convex V shape that is convex toward the top wall 4 a side in a cross-sectional view perpendicular to the extending direction L of the insert mounting seat 4. The rear wall 4c of the insert mounting seat 4 is formed in a flat shape.

[Open / close operation slit]
As shown in FIGS. 3 and 4, the opening / closing operation slit 7 penetrates the insert holding plate 2 in the thickness direction T at the tip of the tool body 1, and the thickness of the insert holding plate 2. Opened on both sides facing the direction T. Moreover, the opening / closing operation slit 7 extends along the extending direction (protruding direction P) of the tool body 1. One end of the opening / closing operation slit 7 in the protruding direction P is formed so as to have a constant slit width, and communicates with the insert mounting seat 4. A round hole is formed at the other end of the opening / closing operation slit 7 opposite to the protruding direction P. Although not particularly illustrated, the other end of the opening / closing operation slit 7 may be formed so that the slit width is constant without forming the round hole.

  An engagement hole 7a for engaging a work tool 60 such as a Torx (registered trademark) wrench or a hexagon wrench is formed in an intermediate portion located between both ends of the opening / closing operation slit 7 along the extending direction of the tool body 1. (See FIGS. 10 to 12). In the example shown in FIG. 4, the length (height) along the tool height direction HT of the engagement hole 7 a is the length along the tool height direction HT of the part other than the engagement hole 7 a of the opening / closing operation slit 7. It is bigger than that.

[Grooving cutting insert]
As shown in FIGS. 5 and 7 to 9, the grooving cutting insert 20 has a rod shape. Of both ends along the extending direction L of the grooving cutting insert 20, a blade portion 27 having a cutting edge 21 is formed at one end portion, and the insert mounting seat 4 is clamped at a portion other than the one end portion. A clamped portion 28 to be clamped is formed.

In FIG. 5, when the grooving cutting insert 20 is mounted on the insert mounting seat 4, the blade portion 27 of the grooving cutting insert 20 has one end portion (opening portion) in the extending direction L of the insert mounting seat 4. ) To the outside of the insert mounting seat 4.
In the example of the present embodiment, the blade portion 27 has a substantially triangular plate shape, and the clamped portion 28 has a substantially pentagonal plate shape.

[Blade]
As shown in FIGS. 8B and 8C, the length (thickness) along the thickness direction T of the blade portion 27 is larger than the length along the thickness direction T of the clamped portion 28. . Moreover, as shown in FIGS. 6A and 6B, the thickness of the blade portion 27 is larger than the thickness of the insert holding plate portion 2. In FIG. 8B, the thickness of the blade portion 27 is gradually increased toward the one end portion side in the extending direction L (from the clamped portion 28 along the extending direction L to the blade portion 27 side).
8A, the length (height) along the insert height direction HI of the blade portion 27 gradually decreases toward the one end portion side in the extending direction L. As shown in FIG.

The blade portion 27 includes a rake face 22, a flank face 23, and a cutting edge 21 formed at a cross ridge line portion between the rake face 22 and the flank face 23.
The rake face 22 is formed on the upper surface of the blade portion 27 and faces upward in the insert height direction HI. The flank 23 is formed on the end surface (front surface) facing the one end side in the extending direction L of the blade portion 27 and on both side surfaces facing the thickness direction T of the blade portion 27. The cutting edge 21 has a U-shape or a U-shape opening toward the other end side in the extending direction L in a top view of the grooving cutting insert 20 shown in FIG.

The cutting edge 21 protrudes most toward the one end part side in the extending direction L at the blade part 27, and protrudes most toward both sides in the thickness direction T.
As shown in FIGS. 7 and 8, the cutting edge 21 is located at the edge on the one end side in the extending direction L of the blade portion 27, and extends along the thickness direction T (front cutting edge). Blade) 21a and a pair of secondary cutting edges (side cutting edges) 21b connected to both ends of the main cutting edge 21a and extending from the main cutting edge 21a toward the other end in the extending direction L. Have.

As shown in FIG. 8B, in the example of the present embodiment, both end portions of the main cutting edge 21a connected to the sub cutting edge 21b are round corners (corner blades) having a convex R shape. Yes. Although not particularly illustrated, both end portions of the main cutting edge 21a may be chamfered corners (corner blades) instead of round corners, or no round corners or chamfered corners are formed. Good.
Further, the pair of sub cutting edges 21b extend so as to gradually approach each other from the main cutting edge 21a toward the other end side in the extending direction L. These sub cutting edges 21b include so-called back tapers. Is granted. Although not particularly illustrated, the sub-cutting blade 21b may be provided with a portion serving as a wiping blade extending perpendicular to the thickness direction T.

  In the blade portion 27, a projection 29 protruding upward in the insert height direction HI is formed on a portion of the rake face 22 on the side opposite to the cutting edge 21 (specifically, the main cutting edge 21a). ing. The protrusion 29 is disposed between the rake face 22 of the blade portion 27 and the upper surface 24 of the clamped portion 28 described later, and extends along the thickness direction T. In the grooving cutting insert 20, the protrusion 29 is formed so as to protrude most up in the insert height direction HI.

  As shown in FIG. 5, in a state where the grooving cutting insert 20 is attached to the insert mounting seat 4, the protrusion 29 is adjacent to the protruding direction P of the tip so as to cover the tip of the upper jaw 5. Be placed. In the example of the present embodiment, a gap is provided between the protrusion 29 and the tip of the upper jaw 5.

[Clamped part]
As shown in FIGS. 5 and 7 to 9, the clamped portion 28 includes an upper surface 24 facing the same direction as the rake surface 22, a lower surface 25 facing the opposite side of the upper surface 24, and other extending directions L. And a back surface 26 facing the end side.

8A, the lower surface 25 of the clamped portion 28 extends along the extending direction L of the grooving cutting insert 20.
And, on the upper surface 24 of the clamped portion 28, a guide portion 24a formed so as to be parallel to the lower surface 25 and an end portion side in the extending direction L of the guide portion 24a are arranged adjacent to each other, There is provided a pressed part 24b formed to be inclined with respect to the lower surface 25 so as to approach the lower surface 25 as it goes toward the one end side.

  Further, the length of the pressed portion 24b along the extending direction L of the grooving cutting insert 20 is set longer than the length of the guide portion 24a along the extending direction L. Specifically, the length of the pressed portion 24b along the extending direction L is 2 to 5 times the length of the guide portion 24a along the extending direction L.

Further, as shown in FIG. 8A, the thickness direction perpendicular to the extending direction L of the grooving cutting insert 20 and the up-down direction connecting the upper surface 24 and the lower surface 25 (that is, the insert height direction HI). As viewed from T, among the acute angle and obtuse angle formed between the pressed portion 24b and the lower surface 25 of the upper surface 24 of the clamped portion 28, the acute angle θ is 1 to 10 °, preferably It is about 2 °.
As described above, the guide portion 24a of the upper surface 24 of the clamped portion 28 is parallel to the lower surface 25, so that an acute angle and an obtuse angle formed between the guide portion 24a and the pressed portion 24b. Among them, the acute angle θ is also 1 to 10 °, preferably about 2 °.

As shown in FIG. 7, FIG. 8C and FIG. 9B, the upper surface 24 and the lower surface 25 of the clamped portion 28 have a concave V-shape in cross section perpendicular to the extending direction L, respectively. I am doing.
For this reason, in FIG. 5, when the grooving cutting insert 20 is mounted on the insert mounting seat 4, the top wall 4 a having a convex V-shaped cross section in the insert mounting seat 4 and the grooving cutting insert 20 The upper surface 24 having a concave V-shaped cross section is brought into contact (locked) in a state where relative movement in the thickness direction T is restricted. Similarly, the bottom wall 4b having a convex V-shaped cross section in the insert mounting seat 4 and the lower surface 25 having a concave V-shaped cross section in the grooving cutting insert 20 are relative to each other in the thickness direction T. Contact is made in a state where movement is restricted.

  In the example of this embodiment, both the upper surface 24 and the lower surface 25 of the grooving cutting insert 20 have a V-shaped cross section, and both the top wall 4a and the bottom wall 4b of the insert mounting seat 4 have a convex V shape. Both of the pair of the top wall 4a and the upper surface 24 and the pair of the bottom wall 4b and the lower surface 25 (two sets) are fitted in a V-shaped cross section. Only one of the sets may have a V-shaped cross-section. In this case, for the other set of the two sets, for example, a configuration in which planes that are not V-shaped in cross-section may be in contact with each other.

  Moreover, you may mutually replace the component of a cross-sectional concave V shape, and the component of a cross-sectional convex V shape. Specifically, the top wall 4a having a V-shaped cross section in the insert mounting seat 4 and the upper surface 24 having a V-shaped cross section in the grooving cutting insert 20 are mutually in the thickness direction T. You may contact | abut in the state in which relative movement was controlled. Further, the bottom wall 4b having a V-shaped cross section in the insert mounting seat 4 and the lower surface 25 having a V-shaped cross section in the grooving cutting insert 20 are relatively moved in the thickness direction T. You may contact | abut in the controlled state.

  That is, at least one of the upper surface 24 and the lower surface 25 of the grooving cutting insert 20 is formed in a V shape (including a concave V shape and a convex V shape) in a cross-sectional view perpendicular to the extending direction L. It only has to be. Correspondingly, at least one of the top wall 4a and the bottom wall 4b of the insert mounting seat 4 is V-shaped (convex V-shaped and concave V-shaped in a cross-sectional view perpendicular to the extending direction L. As long as it is formed).

8A, 8B, and 9A, the back surface 26 of the clamped portion 28 has an inclined wall-shaped back surface portion 26a and a vertical wall-shaped back surface portion 26b.
The inclined wall-like back surface portion 26 a is disposed in the upper portion of the back surface 26 in the insert height direction HI, and is connected to the guide portion 24 a on the upper surface 24. The inclined wall-shaped back surface portion 26a is gradually inclined toward the one end portion side in the extending direction L as it goes upward in the insert height direction HI. As shown in FIG. 8A, in a side view of the grooving cutting insert 20 as viewed from the thickness direction T, an acute angle and an obtuse angle formed between the inclined wall-shaped back surface portion 26a and the lower surface 25. The acute angle β is, for example, 40 to 70 °.

  The vertical wall-shaped back surface portion 26 b is disposed at a lower portion of the back surface 26 in the insert height direction HI and is connected to the lower surface 25. As shown in FIG. 8A, in the side view of the grooving cutting insert 20 as viewed from the thickness direction T, the angle γ formed between the lower surface 25 and the vertical wall-shaped back surface portion 26b is the lower surface. It is set to a value closer to vertical than the angle β formed between the angled wall-like back surface portion 26a and 25. Specifically, the angle γ formed between the lower surface 25 and the vertical wall-shaped back surface portion 26b is preferably an angle close to 90 ° (that is, it is not necessarily strictly 90 °, but is approximately 90 °). Preferably), for example, 80 to 100 °.

  Further, as shown in FIG. 8A, in the side view of the grooving cutting insert 20 as viewed from the thickness direction T, the length of the inclined wall-shaped back surface portion 26a of the back surface 26 is a vertical wall shape. It is made longer than the length of the back surface part 26b. Specifically, in the side view of the insert as viewed from the thickness direction T, the length of the inclined wall-shaped back surface portion 26a is 1.1 to 2 times the length of the vertical wall-shaped back surface portion 26b.

In addition, the inclined wall-shaped back surface portion 26a and the vertical wall-shaped back surface portion 26b are each formed in a planar shape. In the present embodiment, as shown in FIG. 5, with the grooving cutting insert 20 mounted on the insert mounting seat 4, the rear of the insert mounting seat 4 with respect to the inclined wall-shaped back portion 26 a of the back surface 26. The wall 4c is brought into contact.
In the example of the present embodiment, the inclined wall-shaped back surface portion 26a and the rear wall 4c that are in contact with each other have a planar shape, but instead, the inclined wall-shaped back surface portion 26a has a V-shaped cross section. Alternatively, the rear wall 4c may be formed in a convex V shape or a concave V shape so as to correspond to the convex V shape in cross section.

[Attaching / detaching cutting insert for grooving to insert mounting seat]
Next, with reference to FIGS. 10-12, the attachment / detachment method of the cutting insert 20 for grooving to the insert mounting seat 4 is demonstrated.
In the present embodiment, a work tool 60 such as a Torx (registered trademark) wrench or a hexagon wrench is used to attach and detach the grooving cutting insert 20 to the insert mounting seat 4. A portion having the maximum diameter and a portion other than the portion having the maximum diameter (portions not having the maximum diameter) are arranged adjacent to each other at the tip portion of the working tool 60 along the central axis of the tip portion. Has been.

  First, as shown in FIG. 10, the tip of the working tool 60 is inserted into the engagement hole 7 a of the opening / closing operation slit 7 when the insert mounting seat 4 is not fitted with the grooving cutting insert 20. To do. At this time, as shown in FIG. 11, the distal end portion of the working tool 60 engages in the engagement hole 7 a at a portion other than the portion having the maximum diameter in the distal end portion.

  From this state, as shown in FIG. 12, when the distal end portion of the working tool 60 is rotated around its central axis, the portion of the distal end portion having the maximum diameter is engaged in the engagement hole 7a. At the same time, the engagement hole 7a is expanded in the tool height direction HT, and the upper jaw portion 5 is elastically deformed upward. Thereby, the top wall 4a and the bottom wall 4b of the insert mounting seat 4 become parallel. That is, in FIG. 5, the angle θ formed between the top wall 4a and the bottom wall 4b is approximately 0 °.

Next, the grooving cutting insert 20 is inserted toward the other end side in the extending direction L from one end portion (insert insertion port) in the extending direction L of the insert mounting seat 4.
As shown in FIG. 5, when the back surface 26 of the grooving cutting insert 20 comes into contact with the rear wall 4 c of the insert mounting seat 4, the tip of the working tool 60 is rotated around its central axis, A portion other than the portion having the maximum diameter at the tip portion is disposed so as to engage with the engagement hole 7a. Thereby, the upper jaw part 5 is restored and deformed downward, and the grooving cutting insert 20 is clamped between the top wall 4 a and the bottom wall 4 b of the insert mounting seat 4.
Next, the tip of the working tool 60 is removed from the engagement hole 7 a of the opening / closing operation slit 7.

  Further, in order to remove the grooving cutting insert 20 mounted on the insert mounting seat 4, a procedure reverse to the above-described procedure at the time of insert mounting may be performed.

[Effects of this embodiment]
In the grooving cutting insert 20 and the cutting edge exchange type grooving tool 10 of the present embodiment described above, when the grooving cutting insert 20 is mounted on the insert mounting seat 4, the bottom wall 4b of the insert mounting seat 4 is mounted. Are in contact with the lower surface 25 of the cutting insert 20 for grooving. In addition, the guide portion 24a of the upper surface 24 of the grooving cutting insert 20 is first brought into contact with the top wall 4a of the insert mounting seat 4, and the extending direction of the insert mounting seat 4 (of the grooving cutting insert 20). In the state in which the grooving cutting insert 20 is inserted into the insert mounting seat 4 along the extending direction (L) and the grooving cutting insert 20 has been inserted, the insert mounting seat 4 is inserted into the top wall 4a. On the other hand, the pressed portion 24b of the upper surface 24 of the grooving cutting insert 20 is brought into contact.

  Specifically, the guide portion 24a on the upper surface 24 of the grooving cutting insert 20 and the lower surface 25 of the grooving cutting insert 20 are formed so as to be parallel to each other. When the grooving cutting insert 20 is inserted along the extending direction L from one end portion (insert insertion opening) in the direction L, the grooving cutting insert 20 is connected to the top wall 4 a and the bottom of the insert mounting seat 4. It continues to be stably supported between the wall 4b from above and below.

  That is, while the grooving cutting insert 20 is being inserted into the insert mounting seat 4, the bottom wall 4 b of the insert mounting seat 4 continues to slidably contact the lower surface 25 of the grooving cutting insert 20, and the top of the insert mounting seat 4. The wall 4a continues to be in sliding contact with the guide portion 24a of the upper surface 24 of the grooving cutting insert 20. As a result, the grooving cutting insert 20 is stably guided from above and below until it is completely inserted into the insert mounting seat 4, and the grooving cutting insert 20 is prevented from falling off the insert mounting seat 4. The

  Further, in the state where the grooving cutting insert 20 has been inserted into the insert mounting seat 4, one end side (the blade portion 27) of the upper surface 24 of the grooving cutting insert 20 in the extending direction L from the guide portion 24 a. The pressed portion 24b located on the side) is in contact with the top wall 4a of the insert mounting seat 4. Since the pressed portion 24b is inclined on the upper surface 24 of the grooving cutting insert 20 so as to approach the lower surface 25 toward the one end portion, the pressed portion 24b is the top wall of the insert mounting seat 4. By coming into contact (pressed) with 4a, the cutting insert 20 for grooving with respect to the insert mounting seat 4 is prevented from coming off.

In order to stably obtain the effects of the above-described guide portion 24a and pressed portion 24b, the present embodiment is implemented in the insert holding plate portion 2 that is located at the tip portion of the tool body 1 and in which the insert mounting seat 4 is formed. It is preferable to adopt the configuration as described in the embodiment.
That is, when the grooving cutting insert 20 is inserted into the insert mounting seat 4, the insert holding plate portion 2 (specifically, the top wall 4a and the bottom wall 4b of the insert mounting seat 4 are moved away from each other in advance. The upper jaw 5) is elastically deformed, and when the grooving cutting insert 20 has been inserted, the elastic deformation of the insert holding plate 2 is released and restored, and the top wall of the insert mounting seat 4 is restored. 4a is comprised so that it may contact | abut to the to-be-pressed part 24b. Specifically, in a state where the insert holding plate portion 2 is elastically deformed, the top wall 4a and the bottom wall 4b of the insert mounting seat 4 are arranged in parallel to each other, and grooves are formed in the top wall 4a and the bottom wall 4b. The grooving cutting insert 20 may be inserted into the insert mounting seat 4 while the guide portion 24a and the lower surface 25 of the upper surface 24 of the grooving cutting insert 20 are in sliding contact.

  As described above, according to the present embodiment, when the tool is used, the grooving cutting insert 20 can be prevented from coming off from the insert mounting seat 4, and the grooving cutting insert 20 is mounted on the insert mounting seat 4. In this case, it is possible to improve the mounting operability by preventing the grooving cutting insert 20 from falling off.

In the present embodiment, in the grooving cutting insert 20, the length of the pressed portion 24 b along the extending direction L is longer than the length of the guide portion 24 a along the extending direction L. Has an effect.
That is, in this case, when the grooving cutting insert 20 is inserted into the insert mounting seat 4, the grooving cutting insert 20 can be prevented from falling off by the action of the guide portion 24 a described above. Then, in the state where the grooving cutting insert 20 has been mounted on the insert mounting seat 4, the insert mounting is performed on the pressed portion 24b whose length along the extending direction L of the grooving cutting insert 20 is increased. The top wall 4a of the seat 4 can be brought into contact over a wide range. Accordingly, it is possible to effectively prevent the grooving cutting insert 20 from slipping out and to enhance the clamp stability of the grooving cutting insert 20.

Moreover, in this embodiment, in the grooving cutting insert 20, the length of the pressed part 24b along the extending direction L is 2 to 5 times the length of the guide part 24a along the extending direction L. Therefore, the following effects are exhibited.
That is, in this case, when the grooving cutting insert 20 is inserted into the insert mounting seat 4, the grooving cutting insert 20 can be more reliably prevented from falling off, and the grooving cutting insert 20 is attached to the insert mounting seat 4. In the state, the effect of preventing the grooving cutting insert 20 from slipping out and the effect of improving the clamp stability of the grooving cutting insert 20 can be made particularly remarkable.

Specifically, since the length of the pressed portion 24b along the extending direction L of the grooving cutting insert 20 is more than twice the length of the guide portion 24a along the extending direction L, cutting for grooving A sufficient contact area between the pressed portion 24b of the insert 20 and the top wall 4a of the insert mounting seat 4 can be ensured. Accordingly, it is possible to reliably prevent the grooving cutting insert 20 from coming out, and the clamp stability of the grooving cutting insert 20 is significantly improved.
Further, the length of the pressed portion 24b along the extending direction L of the grooving cutting insert 20 is not more than five times the length of the guide portion 24a along the extending direction L. While ensuring the length sufficiently, the length of the guide portion 24a can be suppressed from becoming too short, and the operation of the guide portion 24a can be stabilized. Accordingly, when the grooving cutting insert 20 is mounted on the insert mounting seat 4, the grooving cutting insert 20 can be reliably prevented from falling off.

In the present embodiment, the angle θ formed between the pressed portion 24b and the lower surface 25 in the side view of the insert when the grooving cutting insert 20 is viewed from the thickness direction T is 1 to 10 °. Therefore, the following effects are achieved.
That is, in this case, the effect of preventing the grooving cutting insert 20 from slipping out of the insert mounting seat 4 and the effect of improving the clamp stability by the action of the pressed part 24b described above are more remarkable. can do.

Specifically, as seen from the thickness direction T of the grooving cutting insert 20, the angle θ formed between the pressed portion 24b and the lower surface 25 is 1 ° or more. When the top wall 4a of the insert mounting seat 4 comes into contact with the 20 pressed parts 24b, the above-described effect of preventing the slipping out and the effect of improving the clamp stability can be reliably obtained.
Further, since the angle θ formed between the pressed portion 24b and the lower surface 25 is 10 ° or less when viewed in the thickness direction T of the grooving cutting insert 20, the grooving cutting insert 20 is provided. When the insert mounting plate 4 is mounted, the insert holding plate portion 2 is elastically deformed or restored and deformed (in the present embodiment, the upper jaw portion 5 that has been elastically deformed in advance is restored and deformed). The top wall 4a of the insert mounting seat 4 can be reliably brought into contact with the pressed portion 24b of the grooving cutting insert 20. Therefore, the operational effects of the present embodiment described above can be obtained stably.

In the present embodiment, at least one of the upper surface 24 and the lower surface 25 of the grooving cutting insert 20 is formed in a V shape in a cross-sectional view perpendicular to the extending direction L. Play.
That is, in this case, the movement of the grooving cutting insert 20 with respect to the insert mounting seat 4 in the thickness direction T (the slit penetration direction of the insert mounting seat 4) is restricted, and the operational effects of the above-described embodiment are more stable. It will be a thing.

In the present embodiment, the protruding direction P in which the insert holding plate portion 2 of the tool body 1 protrudes from a portion other than the insert holding plate portion 2 is different from the extending direction L of the insert mounting seat 4. Therefore, the following effects are achieved.
When the tool is separated from the work material W after grooving, the direction in which the tool is retracted with respect to the work material W is the opposite side to the protruding direction P (the opposite side to the grooving direction). The Therefore, when the cutting edge 21 or the like of the grooving cutting insert 20 located in the machined groove in the work material W comes into contact with the inner wall of the groove (when a catching occurs), etc. The direction of the extraction force acting on the cutting insert 20 is along the protruding direction P.
According to the configuration of the present embodiment, the direction in which the grooving cutting insert 20 is removed from the insert mounting seat 4 is along the extending direction L, and the extending direction L is different from the projecting direction P. ing. Therefore, even when the above extraction force is applied to the grooving cutting insert 20, a resistance (frictional force or the like) that restricts the relative movement between the insert mounting seat 4 and the grooving cutting insert 20 is generated. The escape of the grooving cutting insert 20 is effectively suppressed.

In the present embodiment, when the insert holding plate portion 2 is viewed from the thickness direction T, the angle α formed between the extending direction L of the insert mounting seat 4 and the protruding direction P is 15 to 30 °. Therefore, the following effects are achieved.
That is, in this case, the rigidity of the tool body 1 can be sufficiently ensured while preventing the grooving cutting insert 20 from coming out more reliably.

Specifically, since the angle α formed between the extending direction L and the protruding direction P is 15 ° or more, when the extraction force in the protruding direction P is applied to the grooving cutting insert 20. In addition, the resistance generated between the insert mounting seat 4 and the grooving cutting insert 20 can be sufficiently increased, and the slipping out of the grooving cutting insert 20 can be effectively suppressed.
Moreover, since the angle α formed between the extending direction L and the protruding direction P is 30 ° or less, the insert mounting seat 4 (the extending direction L) is in the protruding direction P (grooving direction). Therefore, the rigidity of the lower jaw 6 can be ensured, and the rigidity of the entire tool body 1 can be secured.

Further, in the present embodiment, the inclined wall-like back surface portion 26a of the back surface 26 of the grooving cutting insert 20 is gradually increased in the insert height direction HI as one end portion side (insert insertion port side). Since the rear wall 4c of the insert mounting seat 4 is brought into contact with the inclined wall-shaped back surface portion 26a, the following operational effects are obtained.
That is, in this case, a cutting force directed downward in the tool height direction HT acts on the vicinity of the cutting edge 21 of the grooving cutting insert 20 at the time of grooving. Even when a rotational force is generated around the end near the one end in the extending direction L of the lower surface 25, the rear wall 4 c together with the top wall 4 a of the insert mounting seat 4 suppresses the lifting of the grooving cutting insert 20. Thus, the clamp stability is improved.

In the present embodiment, when the grooving cutting insert 20 is viewed from the thickness direction T, the angle β formed between the inclined wall-shaped back surface portion 26a of the back surface 26 and the bottom surface 25 is 40 to 70 °. Therefore, the following effects are exhibited.
That is, in this case, since the angle β is 40 ° or more, in order to incline the inclined wall-shaped back surface portion 26a with respect to the lower surface 25, in the extending direction L of the grooving cutting insert 20 (the clamped portion 28 thereof). It can suppress that the full length which goes along becomes too large.
Further, since the angle β is 70 ° or less, the above-described effect of suppressing the lifting of the grooving cutting insert 20 becomes more remarkable.

In the present embodiment, as shown in FIG. 8A, when the grooving cutting insert 20 is viewed from the thickness direction T, the length of the inclined wall-shaped back surface portion 26a is equal to that of the vertical wall-shaped back surface portion 26b. Since the length is 1.1 to 2 times, the following effects are obtained.
That is, in this case, the length of the inclined wall-shaped back surface portion 26a is 1.1 times or more of the length of the vertical wall-shaped back surface portion 26b when viewed from the thickness direction T. 26, the effect of suppressing the lifting of the above-described grooving cutting insert 20 by increasing the contact area (contact length) of the inclined wall-like back surface portion 26a to the rear wall 4c of the insert mounting seat 4 reliably. The effect of increasing the stability can be stabilized.
In addition, since the length of the inclined wall-shaped back surface portion 26a is not more than twice the length of the vertical wall-shaped back surface portion 26b when viewed from the thickness direction T, the above-described effect by the inclined wall-shaped back surface portion 26a is obtained. For example, as shown in FIG. 16, when the grooving cutting insert 20 is mounted on the inner diameter grooving tool body 41, the insert mounting seat 4 is brought into contact with the rear wall 4c while being sufficiently obtained. The positioning accuracy of the grooving cutting insert 20 with respect to the insert mounting seat 4 can be stably secured by the vertical wall-shaped back surface portion 26b.

Further, in the present embodiment, the grooving cutting insert 20 is provided with a projection 29 so as to be adjacent to the other end portion side in the extending direction L with respect to the rake face 22, and the projection 29 corresponds to the upper jaw portion 5. Since it arrange | positions so that the front-end | tip may be covered, there exists the following effect.
That is, in this case, chips shed on the rake face 22 from the cutting edge 21 toward the other end side in the extending direction L (on the side opposite to the protruding direction P) are caused to collide with the protrusion 29 during grooving. The wear and damage of the upper jaw 5 due to the scraping of the chips are prevented.
In the example of the present embodiment, a gap is provided between the protrusion 29 and the tip of the upper jaw 5, but these may be in contact with each other. In this case, the rear wall 4c of the insert mounting seat 4 may not contact the back surface 26 of the grooving cutting insert 20.

Second Embodiment
Next, the blade edge replacement type grooving tool 30 according to the second embodiment of the present invention will be described with reference to FIGS. 13 and 14. The blade replacement type grooving tool 30 of the present embodiment also performs outer diameter grooving on the work material W. In addition, the workpiece W may be cut off by using the cutting edge exchange type grooving tool 30.
Detailed description of the same components as those of the above-described embodiment will be omitted, and only differences will be described below.

[Differences from the previous embodiment]
As shown in FIG. 13 and FIG. 14, the cutting edge replaceable grooving tool 30 of this embodiment is different from the cutting edge replaceable grooving tool 10 described in the above embodiment mainly in the shape of the tool body 31 and the slit. 32 is different in shape and having a clamp screw 33.

(Tool body)
In the present embodiment, the tool body 31 has an axial shape (square bar shape) with a square cross section. And the plate-shaped insert holding board part 2 is provided in the edge part (tip part) of the direction (tool axis direction) where the tool main body 31 extends. That is, the length (thickness) in the thickness direction T of the insert holding plate portion 2 in the tool body 31 is made smaller than the length in the thickness direction T of the portion other than the insert holding plate portion 2. Also in the present embodiment, the protruding direction P extends along the tool axis of the tool body 31 when the rake face 22 of the grooving cutting insert 20 is viewed from the top, as viewed from above.

〔slit〕
In the present embodiment, instead of the opening / closing operation slit 7 described in the above-described embodiment, a slit 32 not provided with an engagement hole 7a is formed. The slit 32 extends along the protruding direction P (the extending direction of the tool body 31), and one end of the protruding direction P communicates with the insert mounting seat 4. A round hole is formed at the other end of the slit 32 opposite to the protruding direction P. Of the slits 32, the portions other than the round holes have a constant slit width.

[Clamp screw]
The tool body 31 is screwed with a clamp screw 33 for relatively approaching and separating the upper jaw portion 5 and the lower jaw portion 6 of the insert holding plate portion 2.
In this embodiment, the insert holding plate portion is arranged so that the top wall 4a and the bottom wall 4b of the insert mounting seat 4 are moved closer to each other by screwing (tightening) the clamp screw 33 into a screw hole (not shown). 2 (specifically, the upper jaw 5) is elastically deformed. Then, the top wall 4 a of the insert mounting seat 4 is brought into contact with at least the pressed portion 24 b of the upper surface 24 of the grooving cutting insert 20.

  Specifically, in FIG. 14, the clamp screw 33 is loosened, and the upper jaw 5 is not elastically deformed in this state. Thus, the top wall 4a and the bottom wall 4b of the insert mounting seat 4 are disposed in parallel with each other in a state where the insert holding plate portion 2 is not elastically deformed. The grooving cutting insert 20 is inserted into the insert mounting seat 4 while the guide portion 24a and the lower surface 25 of the upper surface 24 of the grooving cutting insert 20 are brought into sliding contact with the top wall 4a and the bottom wall 4b. .

  As shown in FIG. 13, when the grooving cutting insert 20 has been inserted into the insert mounting seat 4, the clamp screw 33 is screwed in to elastically deform the insert holding plate portion 2, and the top wall 4 a of the insert mounting seat 4. The pressed portion 24b of the upper surface 24 of the grooving cutting insert 20 is pressed. That is, by screwing the clamp screw 33, the top wall 4a of the insert mounting seat 4 is inclined so as to approach the bottom wall 4b toward the one end portion side in the extending direction L, and the pressed portion 24b Abut. Thereby, the cutting insert 20 for grooving is clamped to the insert mounting seat 4.

[Effects of this embodiment]
According to the blade replacement type grooving tool 30 of the present embodiment, the same effects as those of the above-described embodiment can be obtained.

<Third Embodiment>
Next, a blade edge replacement type grooving tool 40 according to a third embodiment of the present invention will be described with reference to FIGS. 15 and 16.
Detailed description of the same components as those of the above-described embodiment will be omitted, and only differences will be described below.

[Differences from the previous embodiment]
As shown in FIGS. 15 and 16, the blade replacement type grooving tool 40 of the present embodiment performs a turning process such as an inner diameter grooving process on a cylindrical work material W. The cutting edge exchange-type grooving tool 40 is moved with respect to the work material W toward the outside in the radial direction perpendicular to the axis A of the work material W (the direction of the white arrow shown in FIG. 15). Then, the inner peripheral surface of the work material W is cut by the cutting edge 21 of the cutting insert 20 for grooving to perform grooving.
The cutting edge replaceable grooving tool 40 of this embodiment is different from the cutting edge replaceable grooving tool 30 described in the above embodiment mainly in the shape of the tool body 41 and the protruding direction P (grooving of the insert holding plate portion 2). Direction) and thickness direction T, and the insert mounting seat 4 are different.

[Tool body and insert holding plate]
In the present embodiment, the tool main body 41 has an axial shape (round bar shape) with a circular cross section. And the plate-shaped insert holding plate part 2 is provided in the edge part (tip part) of the direction (tool axis O direction) where the tool main body 41 extends.
In the present embodiment, the insert holding plate portion 2 of the tool body 41 protrudes from a portion other than the insert holding plate portion 2 in a top view of the tool body 41 when the rake face 22 of the grooving cutting insert 20 is viewed from the front. The protruding direction P is extended so as to be orthogonal to the tool axis O of the tool body 41. The protruding direction P is set to the same direction as the “grooving direction” in which the cutting edge exchange-type grooving tool 40 is moved with respect to the work material W during grooving. The thickness direction T of the insert holding plate portion 2 is along the tool axis O direction.

(Insert mounting seat)
Moreover, one end part (insert insertion port) is opening to the end surface (the side surface of the tool main body 41 in this embodiment) among the both ends along the extending direction L of the insert mounting seat 4. .
The insert mounting seat 4 is inclined and extended upward in the tool height direction HT as it goes in the protruding direction P. Although not shown in particular, the insert mounting seat 4 may gradually extend in the downward direction of the tool height direction HT as it goes in the protruding direction P, or the protruding direction as viewed from the thickness direction T. It may extend along P. In the present embodiment, the rear wall 4 c of the insert mounting seat 4 is brought into contact with the vertical wall-shaped back surface portion 26 b of the back surface 26 of the grooving cutting insert 20.

[Effects of this embodiment]
According to the blade replacement type grooving tool 40 of the present embodiment, the same effects as those of the above-described embodiment can be obtained.

[Other configurations included in the present invention]
In addition, this invention is not limited to the above-mentioned embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.

  For example, in the above-described embodiment, the cutting edge-replaceable grooving tools 10, 30, and 40 perform grooving on the outer peripheral surface or inner peripheral surface of the work material W, but the present invention is not limited thereto. Instead, grooving may be performed on an end surface formed on the work material W (a surface facing the direction along the axis A of the work material W).

  Further, the angles α, β, γ, and θ are not limited to the numerical ranges described in the above embodiments.

  Further, in the above-described embodiment, the description has been given by using the cutting edge exchanging grooving tools 10, 30, and 40 (blank exchanging grooving tool) for turning (turning). The present invention can also be applied to a cutting edge exchange type grooving tool (blade cutting type grooving cutter) for milling). In this case, although not particularly illustrated, for example, the tool main body has a disc shape, and a plurality of insert holding plate portions 2 are provided on the outer periphery of the tool main body so as to be spaced apart from each other in the circumferential direction around the tool axis (rotary axis). Is provided. Moreover, the one end part (insert insertion port) along the extending direction L of the insert mounting seat 4 formed in the insert holding plate part 2 is opened toward the outside in the radial direction perpendicular to the tool axis. Then, a grooving cutting insert 20 is detachably attached to each insert mounting seat 4.

  In addition, in the range which does not deviate from the meaning of this invention, you may combine each structure (component) demonstrated by the above-mentioned embodiment, a modification, and a remark etc., addition of a structure, omission, substitution, others It can be changed. Further, the present invention is not limited by the above-described embodiments, and is limited only by the scope of the claims.

DESCRIPTION OF SYMBOLS 1, 31, 41 Tool main body 2 Insert holding plate part 4 Insert mounting seat 4a Top wall 4b Bottom wall 10, 30, 40 Cutting edge exchange grooving tool 20 Cutting insert for grooving 21 Cutting edge 22 Rake face 23 Escape face 24 Upper face 24a Guide portion 24b Pressed portion 25 Lower surface 27 Blade portion 28 Clamped portion HI Insert height direction (vertical direction)
L Extension direction T Thickness direction θ Angle

Claims (6)

A cutting insert for grooving that has a rod shape, a blade portion is formed at one end portion of both end portions along the extending direction, and a clamped portion is formed at a portion other than the one end portion along the extending direction. Because
The blade portion is
Rake face,
Flank and
A cutting edge formed at the intersection ridge line portion of the rake face and the flank face,
The clamped part is
An upper surface facing the same direction as the rake surface;
A lower surface facing away from the upper surface,
On the upper surface,
A guide portion formed to be parallel to the lower surface;
A pressed portion that is arranged adjacent to one end side in the extending direction of the guide portion and is inclined with respect to the lower surface so as to approach the lower surface toward the one end portion; A grooving cutting insert characterized in that is provided. The grooving cutting insert according to claim 1,
A grooving cutting insert, wherein a length of the pressed part along the extending direction is longer than a length of the guide part along the extending direction. A grooving cutting insert according to claim 2,
The length of the pressed part along the extending direction is 2 to 5 times the length of the guide part along the extending direction. A grooving cutting insert according to any one of claims 1 to 3,
An angle formed between the pressed portion and the lower surface when viewed from the extending direction of the cutting insert for grooving and a thickness direction orthogonal to the vertical direction connecting the upper surface and the lower surface. A cutting insert for grooving characterized by being 1 to 10 °. A grooving cutting insert according to any one of claims 1 to 4,
At least one of the upper surface and the lower surface is formed in a V shape in a cross-sectional view perpendicular to the extending direction. An insert holding plate provided on the tool body;
An insert that penetrates the insert holding plate portion in the thickness direction of the insert holding plate portion, extends in a slit shape, and one end portion of both end portions along the extending direction opens to an end surface of the insert holding plate portion. A mounting seat;
A cutting edge for grooving, which has a cutting edge protruding from the one end of the insert mounting seat and is detachably mounted on the insert mounting seat, and a blade-exchangeable grooving tool comprising:
As the grooving cutting insert, using the grooving cutting insert according to any one of claims 1 to 5,
The insert mounting seat is
A top wall in contact with the upper surface;
An edge-changing grooving tool comprising: a bottom wall abutting against the lower surface.

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