JP2023114877A - Cutting edge replaceable cutting tool - Google Patents

Abstract

To provide a cutting edge replaceable cutting tool exhibiting high workability when a cutting insert is attached/detached.SOLUTION: A holder 10 has a female screw hole 11 with which a fastening member 70 is engaged. The female screw hole 11 has a holder female screw 14 that spirally extends away from a clamp piece 30 in a center axis direction toward one side in a peripheral direction. The fastening member 70 has a first screw member 40, and a second screw member 50 inserted into the first screw member 40. The first screw member 40 has a first male screw 43 engaged with the holder female screw 14, and a first female screw 44 that spirally extends so as to come closer to the clamp piece 30 in the center axis direction toward one side in the peripheral direction. The second screw member 50 has a second male screw 54 engaged with the first female screw 44, and a first flange part 52 that can come into contact with the clamp piece 30 from a side opposite the female screw hole 11. A regulation member 60 permits a movement in the center axis direction while regulating rotation of the second screw member 50 about a center axis C.SELECTED DRAWING: Figure 4

Description

The present invention relates to an indexable cutting tool.

As an example of an indexable cutting tool, one described in Patent Document 1 is known. This indexable cutting tool includes a holder, a cutting insert mounted on an insert mounting seat formed in the holder, a clamp piece for pressing the cutting insert against the holder, a screw insertion hole inserted into the clamp piece, and attached to the holder. and a screwed clamp screw.

When attaching the cutting insert to the holder, the clamp screw is rotated a predetermined number of times or more around the central axis of the screw. As a result, the clamp piece presses the cutting insert and pulls the cutting insert toward the rear end of the tool, thereby fixing the cutting insert to the insert mounting seat.

Japanese Patent No. 2701514

In this type of indexable cutting tool, there is room for improvement in terms of improving workability when attaching and detaching the cutting insert.

It is an object of the present invention to provide an indexable cutting tool with good workability when attaching and detaching a cutting insert to and from a holder.

One aspect of the indexable cutting tool of the present invention comprises a holder having an insert mounting seat, a cutting insert detachably mounted on the insert mounting seat, and a clamp fixing the cutting insert to the insert mounting seat. a piece, a fastening member that fastens the clamp piece to the holder, and a regulating member that is provided on the holder and contacts a part of the fastening member, and the fastening member is screwed to the holder. A female screw hole is provided, and the female screw hole has an opening that opens toward the clamp piece, and an opening that extends from the clamp piece in the central axis direction toward one side of the female screw hole in the circumferential direction around the central axis of the female screw hole. and a holder female screw spirally extending away from the fastening member. a screw member, wherein the first screw member is disposed on the outer peripheral surface of the first screw member and screwed with the female screw of the holder; and the inner peripheral surface of the first screw member. and a first female screw that spirally extends toward the one side in the circumferential direction so as to approach the clamp piece in the central axis direction, wherein the second screw member is the second screw A second male screw that is arranged on the outer peripheral surface of the member and is screwed with the first female screw, and a first flange that can contact the clamp piece from the opposite side of the female screw hole in the central axis direction. The restricting member restricts rotation of the second screw member about the central axis while permitting movement in the central axis direction.

According to the indexable cutting tool of the present invention, when the operator rotates the first screw member around the central axis by one turn, for example, the second screw member is rotated by the female screw of the holder and the first male screw. It moves in the central axis direction along the female screw hole of the holder by the sum of the screw pitch of the screw and the screw pitches of the first female screw and the second male screw.
Therefore, the clamp piece can be pressed by the second screw member while the amount of rotation of the working tool is kept small, and the cutting insert can be pressed and fixed to the insert mounting seat via the clamp piece.

Specifically, unlike the present invention, for example, unlike the conventional case where a single clamp screw is used to fasten the clamp piece to the holder, according to the present invention, the work tool is rotated around the central axis. The clamp piece can be fastened to the holder by the fastening member while keeping the number and rotation angle small.

Therefore, according to the present invention, workability is good when attaching and detaching the cutting insert to and from the holder. Since the attachment and detachment of the cutting insert can be completed easily and in a short time, the workability when using the indexable cutting tool can be further improved. In addition, the cutting insert can be fixed to the holder with more stable mounting accuracy by facilitating the attachment and detachment work.

In the indexable cutting tool, the clamp piece has a long hole penetrating the clamp piece in the central axis direction, and the long hole extends in a direction orthogonal to the central axis when viewed from the central axis direction. The second screw member has an open position at which the first flange portion can pass through the elongated hole in the central axis direction, and an open position where the first flange portion and the clamp piece are positioned when viewed from the central axis direction. It is preferable that it is rotatable about the central axis between the overlapping fastening positions.

In this case, by setting the second screw member to the open position, the first flange portion can be inserted through the long hole of the clamp piece, and the clamp piece can be easily attached and detached. Further, when the second screw member is set to the fastening position, the first flange portion extends in a direction intersecting the direction in which the elongated hole extends and overlaps the clamp piece when viewed from the central axis direction. Thereby, the clamp piece can be stably pressed by the first flange portion. As a result, the clamp piece can more stably fix the cutting insert to the holder.

In the indexable cutting tool, it is preferable that the second screw member further includes a second flange portion that can contact the clamp piece from the female screw hole side in the central axis direction.

In this case, when the clamp piece is removed from the holder, the second flange portion contacts the clamp piece from the female screw hole side (lower side), so that the clamp piece can be pushed away from the holder. Therefore, the clamp piece can be removed from the holder more easily.

In the indexable cutting tool, the first screw member has a cylindrical shape centered on the central axis, a cylindrical portion having the first male thread formed on an outer peripheral surface, and a cylindrical portion formed integrally with the cylindrical portion. and a disc extending in a direction perpendicular to the central axis, the disc extending in the central axis direction and having an engagement hole that can be engaged with a work tool.

In this case, since the engagement hole is formed in the disc portion of the first screw member, the first screw can be easily and quickly screwed by engaging the working tool with the engagement hole and rotating it around the central axis. The member can be rotated. As a result, it is possible to further improve the workability when exchanging the cutting insert.

In the indexable cutting tool, the second screw member has a through hole penetrating the second screw member in the central axis direction, and the through hole is the engaging hole when viewed from the central axis direction. It is preferable to overlap with

In this case, the working tool can be engaged with the engaging hole through the through hole of the second screw member. For this reason, the operator can rotate the first screw member by using the work tool from the clamp piece side (upper side) of the holder, which further enhances workability.

In the indexable cutting tool, the holder has a horizontal hole extending from a direction intersecting the central axis toward the female screw hole and into which the restricting member is inserted, and the second screw member has the It is preferable that an engaging portion facing the lateral hole is provided, and the tip portion of the restricting member is engaged with the engaging portion.

In this case, the simple structure can stably restrict the rotation of the second screw member around the central axis.

According to the indexable cutting tool of the aspect of the present invention, workability is good when attaching and detaching the cutting insert to and from the holder.

FIG. 1 is an exploded perspective view showing the indexable cutting tool of this embodiment. FIG. 2 is a top view showing a part of the indexable cutting tool of this embodiment. FIG. 3 is a sectional view showing the III-III section of FIG. FIG. 4 is a partially cutaway perspective sectional view of the indexable cutting tool, showing a state in which the work tool is locked to the fastening member. FIG. 5 is an exploded perspective view showing a clamp piece, a second screw member and a regulating member. FIG. 6 is a perspective view showing the clamp piece, the second screw member, and the regulating member, showing a state where the second screw member is at the open position with respect to the clamp piece. FIG. 7 is a perspective view showing the clamp piece, the second screw member, and the regulating member, showing a state where the second screw member is in the fastening position with respect to the clamp piece.

An indexable cutting tool 1 according to one embodiment of the present invention will be described with reference to the drawings. The indexable cutting tool 1 of the present embodiment is an indexable turning tool such as an indexable cutting tool used for turning, and is detachably attached to a tool post of a machine tool such as a lathe (not shown). be done. In this embodiment, the indexable cutting tool 1 may be simply referred to as a cutting tool or a tool.

As shown in FIGS. 1 to 4, the indexable cutting tool 1 includes a holder 10, a cutting insert 20, a clamp piece 30, a fastening member 70, a regulating member 60, and a working tool 100. . The holder 10 has an insert mounting seat 12 to which the cutting insert 20 is mounted, and a female screw hole 11 into which the fastening member 70 is screwed. The fastening member 70 has a first screw member 40 screwed into the female screw hole 11 and a second screw member 50 screwed into the first screw member 40 .

[Definition of direction]
In this embodiment, the direction in which the central axis C of the female screw hole 11 extends is called the central axis direction. As shown in FIGS. 3 and 4, the clamp piece 30 and the first screw member 40 are arranged at different positions in the central axis direction. Of the central axis directions, the direction from the clamp piece 30 to the first screw member 40 is called one side of the central axis direction, and the direction from the first screw member 40 to the clamp piece 30 is called the other side of the central axis direction. Note that the direction of the central axis may also be called the vertical direction. For this reason, one side in the direction of the central axis may be called the lower side, and the other side in the direction of the central axis may be called the upper side.

A direction perpendicular to the central axis C is called a radial direction. Of the radial directions, the direction closer to the central axis C is called the radial inner side, and the direction away from the central axis C is called the radial outer side.
The direction of rotation around the central axis C is called the circumferential direction. Among the circumferential directions around the central axis C, a predetermined direction is called a circumferential direction one side (+θ side), and a side opposite to the predetermined direction is called a circumferential direction other side (−θ side). In this embodiment, when the cutting tool is viewed from above along the central axis direction, one side in the circumferential direction (+θ side) is the clockwise direction, and the other side in the circumferential direction (−θ side) is the counterclockwise direction. is.

As shown in FIG. 1, the holder 10 has a substantially prismatic shape extending in one direction. In this embodiment, the direction in which the tool center axis (not shown) of the holder 10 extends (that is, the one direction) is called the tool axis direction. An insert mounting seat 12 is formed at the first end of the first end and the second end, which are both ends of the holder 10 in the tool axial direction. Of the tool axial directions, the direction from the first end to the second end is called the tool rear end side, and the direction from the second end to the first end is called the tool front end side.

〔holder〕
The holder 10 is made of metal such as steel. As shown in FIGS. 1 to 4, the holder 10 has an insert mounting seat 12, a female screw hole 11, an inclined surface 17, a locking groove 15, and a horizontal hole 16. As shown in FIG.

The insert mounting seat 12 is arranged at the first end of the holder 10 , that is, the end on the tip side of the tool, and opens to the upper surface, the tip surface and the side surface of the holder 10 . The insert mounting seat 12 has a concave shape recessed from the upper surface, the tip surface and the side surface of the holder 10 . The insert mounting seat 12 is a recess that can receive the cutting insert 20 . The insert mounting seat 12 has, for example, a substantially polygonal concave shape, and in this embodiment, a substantially square concave shape.
The insert mounting seat 12 has a bottom surface that contacts the back surface of the cutting insert 20 and a plurality of (two in this embodiment) wall surfaces that contact the outer surface of the cutting insert 20 .

The insert mounting seat 12 also has a seat member 12b. In this embodiment, the sheet member 12b has a rectangular plate shape. The seat member 12 b constitutes the bottom surface of the insert mounting seat 12 . More specifically, one of the pair of plate surfaces of the seat member 12 b (upper surface) facing upward serves as the bottom surface of the insert mounting seat 12 .

The female screw hole 11 is arranged at the first end (holder tip) of the holder 10 . The female screw hole 11 is arranged adjacent to the tool rear end side of the insert mounting seat 12 . The female screw hole 11 penetrates the holder 10 in the central axis direction. The female screw hole 11 is arranged below the clamp piece 30 . The female screw hole 11 overlaps the clamp piece 30 when viewed from the central axis direction. The female screw hole 11 has an opening 13 and a holder female screw 14 .

The opening 13 is arranged at the upper end of the female screw hole 11 and opens upward. That is, the opening 13 corresponds to the upper opening among the upper opening and the lower opening positioned at both ends of the female screw hole 11 in the central axis direction. The opening 13 opens toward the clamp piece 30 . The opening 13 has a circular hole shape centered on the central axis C. As shown in FIG.

The female screw 14 of the holder is formed on the inner peripheral surface of the female screw hole 11 . Holder female screw 14 is arranged below opening 13 . In the present embodiment, the holder female screw 14 constitutes a portion of the female screw hole 11 other than the opening 13 (a portion other than the upper end portion). The holder female thread 14 spirally extends away from the clamp piece 30 in the central axis direction as it goes to one side (+θ side) in the circumferential direction around the central axis C. As shown in FIG. That is, the holder female thread 14 is a helical female thread centered on the central axis C, and extends downward toward one side in the circumferential direction. In this embodiment, the female thread 14 of the holder is a so-called right-hand thread (positive thread).

An inclined surface 17 is arranged at the first end of the holder 10 . The inclined surface 17 is arranged adjacent to the tool rear end side of the female screw hole 11 . The inclined surface 17 is arranged on the upper surface of the holder 10 . The inclined surface 17 is a flat surface that is inclined downward toward the rear end of the tool.

A locking groove 15 is arranged at the first end of the holder 10 . The locking groove 15 is arranged adjacent to the tool rear end side of the female screw hole 11 . The locking groove 15 is arranged on the side opposite to the insert mounting seat 12 with the female screw hole 11 interposed therebetween when viewed from the upper side of the tool. The locking groove 15 is recessed downward from the upper surface of the holder 10 and has a groove shape extending in a radial direction perpendicular to the central axis C. As shown in FIG. At least part of the locking groove 15 is arranged on the inclined surface 17 .

As shown in FIG. 4 , the lateral hole 16 extends from the direction intersecting the central axis C toward the female screw hole 11 . In this embodiment, the horizontal hole 16 extends in a radial direction perpendicular to the central axis C. As shown in FIG. Both ends of the horizontal hole 16 open to the outer surface of the holder 10 and the female screw hole 11 . In this embodiment, the lateral hole 16 opens to the side surface of the holder 10 and the opening 13 of the female screw hole 11 . The lateral hole 16 has a female screw portion 16a on the inner peripheral surface of the lateral hole 16 .

[Cutting insert]
The cutting insert 20 is made of cemented carbide, PCD (polycrystalline diamond), cBN (cubic boron nitride), cermet, ceramic, or the like, for example. The cutting insert 20 is a hard sintered body having higher hardness than the holder 10 . The cutting insert 20 is detachably attached to the insert mounting seat 12 .

As shown in FIGS. 1 to 4, the cutting insert 20 has a plate-like shape centered on the central axis A of the insert. The cutting insert 20 has, for example, a polygonal plate shape, and in this embodiment, has a rectangular plate shape. The cutting insert 20 is, for example, a rhombic insert conforming to ISO standards. The cutting insert 20 has multiple corners. The cutting insert 20 of this embodiment has a symmetrical shape with the front and back reversed, and is a so-called double-sided type. However, not limited to this, the cutting insert 20 may be of a so-called single-sided type.

The cutting insert 20 is connected to the front surface and the back surface facing the insert axial direction, which is the direction in which the insert central axis A extends, and the front surface and the back surface facing outward in the insert radial direction, which is the direction perpendicular to the insert central axis A. It has an outer surface, a cutting edge 22 arranged at least on a ridge where the surface and the outer surface are connected, and a through hole 21 .

The cutting edge 22 is arranged at the corner portion of the cutting insert 20 . In this embodiment, the cutting edge 22 has a V shape that protrudes outward in the radial direction of the insert. The cutting edge 22 has a convexly curved corner edge and a pair of straight straight edges connected to both ends of the corner edge.

The through hole 21 is arranged in the central portion of the cutting insert 20 when the cutting insert 20 is viewed from above. The through hole 21 passes through the cutting insert 20 in the insert axial direction and opens on the front and back surfaces. The through hole 21 has a circular shape centered on the central axis A of the insert.

[Clamp piece]
The clamp piece 30 is arranged on the upper surface of the first end of the holder 10 . The clamp piece 30 fixes the cutting insert 20 to the insert mounting seat 12 . The clamp piece 30 has a substantially plate shape extending in a direction perpendicular to the central axis C. As shown in FIG. The clamp piece 30 has a piece main body 31 , a slide surface 35 , a locking portion 32 , a projecting portion 33 and an elongated hole 34 .

The piece body 31 has a thick plate shape extending from the through hole 21 of the cutting insert 20 to the locking groove 15 of the holder 10 . That is, the piece body 31 extends radially. The end (tip) of the piece main body 31 on the tool tip side is arranged above the surface of the cutting insert 20 . The end (rear end) of the piece main body 31 on the tool rear end side is arranged above the inclined surface 17 and the locking groove 15 . An intermediate portion of the piece main body 31 located between the front end portion and the rear end portion is arranged above the female screw hole 11 .

The slide surface 35 is arranged at the rear end of the piece main body 31 and faces downward. The slide surface 35 has an inclined planar shape positioned downward toward the rear end side of the tool. The slide surface 35 is in slidable contact with the inclined surface 17 of the holder 10 .

The locking portion 32 is arranged at the rear end portion of the piece main body 31 . The engaging portion 32 protrudes downward from the lower surface of the piece main body 31 . The locking portion 32 has a columnar shape extending in the central axis direction. At least part of the locking portion 32 is arranged on the slide surface 35 . The locking portion 32 is inserted into the locking groove 15 of the holder 10 . The locking portion 32 is movable within the locking groove 15 along the direction in which the locking groove 15 extends, that is, along the radial direction.

The projecting portion 33 is arranged at the tip portion of the piece main body 31 . The protruding portion 33 protrudes downward from the lower surface of the piece body 31 . The projecting portion 33 has a columnar shape extending in the central axis direction. The projecting portion 33 is inserted into the through hole 21 of the cutting insert 20 . The outer peripheral surface of the projecting portion 33 contacts the inner peripheral surface of the through hole 21 . Specifically, the projecting portion 33 contacts the end portion on the central axis C side of the inner peripheral surface of the through hole 21 (the inner end portion in the radial direction orthogonal to the central axis C).
A portion of the lower surface of the piece main body 31 that surrounds the projecting portion 33 contacts the surface of the cutting insert 20 from above.

The long hole 34 vertically penetrates the piece main body 31 . That is, the long hole 34 penetrates the clamp piece 30 in the central axis direction. The long hole 34 overlaps with the female screw hole 11 when viewed from the central axis direction. The long hole 34 extends in a direction perpendicular to the central axis C, that is, in a radial direction when viewed from the central axis direction. Specifically, the shape of the elongated hole 34 is an elliptical shape having a major axis in a predetermined radial direction among the radial directions when viewed from the top of the cutting tool. In this embodiment, the long axis of the long hole 34 extends along an imaginary straight line (not shown) connecting the through hole 21 of the cutting insert 20 and the locking groove 15 of the holder 10 when the tool is viewed from above.

[Fastening member]
The fastening member 70 fastens the clamp piece 30 to the holder 10 . The fastening member 70 fastens the cutting insert 20 to the insert mounting seat 12 via the clamp piece 30 . The fastening member 70 has a cylindrical first screw member 40 extending in the central axis direction and a second screw member 50 inserted inside the first screw member 40 .

The first screw member 40 is inserted inside the female screw hole 11 . The first screw member 40 has a bottomed cylindrical shape centered on the central axis C. As shown in FIG. The first screw member 40 extends in the central axis direction. The first screw member 40 has a cylindrical portion 41 , a first male screw 43 , a first female screw 44 and a disk portion 42 .

The cylindrical portion 41 has a cylindrical shape centered on the central axis C and extends in the central axis direction. A first male screw 43 is formed on the outer peripheral surface of the cylindrical portion 41 . That is, the first male screw 43 is arranged on the outer peripheral surface of the first screw member 40 .

The first male screw 43 spirally extends away from the clamp piece 30 in the central axis direction as it goes to one circumferential direction side (+θ side) around the central axis C. As shown in FIG. That is, the first male thread 43 is a spiral male thread centered on the central axis C, and extends downward toward one side in the circumferential direction. In this embodiment, the first male screw 43 is a so-called right-handed screw (positive screw).

The first male screw 43 is screwed into the holder female screw 14 formed in the female screw hole 11 . That is, the directions of the helices of the first male screw 43 and the holder female screw 14 are the same, and the screw pitches of the screws are the same. In this embodiment, each screw of the first male screw 43 and the holder female screw 14 is, for example, M6×P1.75.

A first female thread 44 is formed on the inner peripheral surface of the cylindrical portion 41 . That is, the first female screw 44 is arranged on the inner peripheral surface of the first screw member 40 . The first female screw 44 spirally extends toward the clamp piece 30 in the central axis direction as it goes toward one side (+θ side) in the circumferential direction around the central axis C. As shown in FIG. That is, the first female thread 44 is a helical female thread centered on the central axis C, and extends upward toward one side in the circumferential direction. In other words, the first female thread 44 extends downward toward the other circumferential side (−θ side). In this embodiment, the first female thread 44 is a so-called left-hand thread (reverse thread).

The disc portion 42 is connected to the lower end portion of the cylindrical portion 41 . In this embodiment, the disc portion 42 is formed integrally with the cylindrical portion 41 . The disc portion 42 has a disc shape extending in a direction perpendicular to the central axis C. As shown in FIG. The disc portion 42 has an engagement hole 45 .

The engagement hole 45 is positioned on the central axis C of the disc portion 42, that is, in the central portion. The engagement hole 45 extends in the central axis direction. In this embodiment, the engagement hole 45 penetrates the disk portion 42 in the central axis direction. The engagement hole 45 has a cross-sectional shape perpendicular to the central axis C, for example, a polygon or a star. The engaging hole 45 is a non-circular key hole or the like that can be engaged with the working tool 100 .

The second screw member 50 has a substantially cylindrical shape centered on the central axis C. As shown in FIG. The second screw member 50 extends in the central axis direction. The second screw member 50 is inserted into the first screw member 40 at its lower portion including at least the lower end. The upper portion of the second screw member 50 protrudes above the first screw member 40 . The upper end of the second screw member 50 is arranged above the female screw hole 11 , and the portion other than the upper end of the second screw member 50 is arranged inside the female screw hole 11 . In this embodiment, the dimension of the second screw member 50 in the central axis direction is larger than the dimension of the first screw member 40 in the central axis direction.

As shown in FIG. 5, the second screw member 50 includes a second screw member main body 51, a first flange portion 52, a second flange portion 53, a second male screw 54, an engaging portion 55, and a penetrating portion. and a hole 56 .

The second screw member main body 51 has a substantially cylindrical shape centered on the central axis C. As shown in FIG. The second screw member main body 51 extends in the central axis direction.

The first flange portion 52 is arranged at the upper end portion of the second screw member main body 51 in the central axis direction. The first flange portion 52 protrudes radially outward from the upper end portion of the second screw member main body 51 . The first flange portion 52 has an oval shape extending radially about the central axis C when viewed from above in the central axis direction. In this embodiment, when viewed from the central axis direction, the oval shape of the first flange portion 52 is similar to the oval shape of the long hole 34 of the clamp piece 30, and the length of the first flange portion 52 is similar to that of the long hole 34 of the clamp piece 30. The circular shape is slightly smaller than the oval shape of slot 34 . That is, as shown in FIGS. 5 and 6, the first flange portion 52 has a shape and dimensions that allow it to pass through the long hole 34 in the central axis direction.

Specifically, in a state in which the long axis of the oval shape of the first flange portion 52 and the long axis of the oval shape of the long hole 34 are arranged substantially parallel to each other when viewed from the central axis direction, the first flange portion 52 is: It can pass through the long hole 34 in the central axis direction. In the present embodiment, the state in which the first flange portion 52 can pass through the long hole 34 in the central axis direction is referred to as the "open position" of the second screw member 50 .

Further, as shown in FIG. 7, when the second screw member 50 is rotated about the central axis C by 90° from the open position with respect to the clamp piece 30, the first flange portion 52 is positioned relative to the clamp piece 30. , and can be contacted from the side opposite to the female screw hole 11 in the central axis direction.

Specifically, in a state in which the major axis of the oval shape of the first flange portion 52 and the major axis of the oval shape of the elongated hole 34 are arranged so as to be substantially perpendicular to each other when viewed from the central axis direction, the first flange portion 52 is arranged so as to be substantially perpendicular to each other. can contact the portion of the bridge main body 31 located around the long hole 34 from above in the direction of the center axis. In this embodiment, the first flange portion 52 cannot pass through the long hole 34 in the central axis direction, that is, the state in which the first flange portion 52 and the clamp piece 30 overlap when viewed from the central axis direction (the first flange portion 52 can contact the clamp piece 30 from the central axis direction) is referred to as the second screw member 50 being in the "fastening position".
The second screw member 50 is rotatable around the central axis C between the open position and the tightened position.

As shown in FIG. 5 , the second flange portion 53 is arranged downwardly away from the first flange portion 52 . The second flange portion 53 protrudes radially outward from the second screw member main body 51 . In this embodiment, the second flange portion 53 has a substantially cylindrical shape centered on the central axis C. As shown in FIG. When viewed from the central axis direction, the outer diameter dimension of the second flange portion 53 is larger than the dimension of the elongated hole 34 in the minor axis direction. Therefore, the second flange portion 53 can contact the clamp piece 30 from the female screw hole 11 side in the central axis direction. Specifically, the second flange portion 53 can contact the portion of the bridge main body 31 located around the long hole 34 from below in the central axis direction.

The second male screw 54 is arranged below the second flange portion 53 . The second male screw 54 is arranged on the lower portion of the outer peripheral surface of the second screw member main body 51 . That is, the second male screw 54 is arranged on the outer peripheral surface of the second screw member 50 .

The second male thread 54 spirally extends toward one side (+θ side) in the circumferential direction around the central axis C so as to approach the clamp piece 30 in the central axis direction. That is, the second male thread 54 is a spiral male thread centered on the central axis C, and extends upward toward one side in the circumferential direction. In other words, the second male screw 54 extends downward toward the other circumferential side (−θ side). In this embodiment, the second male thread 54 is a so-called left-hand thread (reverse thread).

As shown in FIGS. 3 and 4 , the second male thread 54 is screwed into the first female thread 44 formed on the first screw member 40 . That is, the directions of the spirals in which the threads of the second male thread 54 and the first female thread 44 extend are the same, and the screw pitches of the threads are the same. In this embodiment, each screw of the second male screw 54 and the first female screw 44 is, for example, M4×P1.25.

In the present embodiment, the screw pitch of the first male screw 43 and the holder female screw 14 (P=1.75 mm as an example) is the same as the screw pitch of the second male screw 54 and the first female screw 44 (as an example , P = 1.25 mm).

As shown in FIG. 5, the engaging portion 55 is arranged between the first flange portion 52 and the second male screw 54 in the central axis direction. In this embodiment, the engaging portion 55 is arranged on a portion of the second flange portion 53 in the circumferential direction. The engaging portion 55 is recessed radially inward from the outer peripheral surface of the second flange portion 53 and has a groove shape extending in the central axis direction. The engaging portion 55 has a flat surface extending in a direction perpendicular to the radial direction. This flat surface constitutes the bottom surface of the groove of the engaging portion 55 and faces radially outward.
As shown in FIG. 4, when the fastening member 70 is attached to the female screw hole 11 and the second screw member 50 is in the fastening position, the engaging portion 55 faces the lateral hole 16 of the holder 10 in the radial direction.

The through hole 56 penetrates the second screw member main body 51 in the vertical direction. That is, the through hole 56 penetrates the second screw member 50 in the central axis direction. The through hole 56 has a circular shape centered on the central axis C and extends in the central axis direction. The through hole 56 is arranged above the engaging hole 45 of the first screw member 40 . The through hole 56 overlaps the engaging hole 45 when viewed from the central axis direction.

[Regulation member]
The restricting member 60 is inserted into the horizontal hole 16 of the holder 10 . The regulating member 60 is provided on the holder 10 and contacts a portion of the fastening member 70 (the engaging portion 55 in this embodiment). As shown in FIGS. 4 and 5, the restricting member 60 has a substantially cylindrical shape. A central axis of the regulating member 60 extends in a direction intersecting with the central axis C. As shown in FIG. In this embodiment, the central axis of the restricting member 60 extends in a radial direction perpendicular to the central axis C. As shown in FIG. The restricting member 60 is, for example, a set screw or the like. The restricting member 60 has a male screw portion 61 and a contact portion 62 .

The male threaded portion 61 is arranged at a portion of the outer peripheral surface of the restricting member 60 other than the inner end portion in the radial direction orthogonal to the central axis C. As shown in FIG. In other words, the male threaded portion 61 is arranged at a portion other than the distal end portion of the restricting member 60 in the direction along the central axis of the restricting member 60 . The male threaded portion 61 is screwed into the female threaded portion 16 a of the lateral hole 16 .

A worker locks a wrench tool such as a hexagonal wrench (not shown) in a hole such as a hexagonal hole that opens in the rear end surface of the regulating member 60, and rotates the regulating member 60 with the wrench tool so that the female screw portion 16a is The screwing amount of the male screw portion 61 can be changed. Thereby, the regulating member 60 can advance and retreat in the horizontal hole 16 in the radial direction.

The contact portion 62 is arranged at the radially inner end portion of the restricting member 60 . In other words, the contact portion 62 is arranged at the distal end portion of the restricting member 60 in the direction along the central axis of the restricting member 60 . The contact portion 62 has a columnar shape extending in the radial direction, and is cylindrical in this embodiment. The tip surface of the contact portion 62 is, for example, a circular planar shape. The tip surface of the contact portion 62 contacts the flat surface of the engaging portion 55 of the second screw member 50 . That is, the tip portion of the contact portion 62 contacts the engaging portion 55 . As a result, the distal end portion of the restricting member 60 is engaged with the engaging portion 55 .

As shown in FIGS. 4 and 7, in a state where the restricting member 60 is engaged with the engaging portion 55, the second screw member 50 moves within a predetermined range in the central axis direction with respect to the female screw hole 11. Rotation around the central axis C is permitted and restricted. In other words, the restricting member 60 restricts the rotation of the second screw member 50 about the central axis C, while permitting movement in the central axis direction.

[Tools for work]
As shown in FIG. 4 , the indexable cutting tool 1 of this embodiment includes a working tool 100 for manipulating the fastening member 70 . The working tool 100 is, for example, a wrench tool. Therefore, the indexable cutting tool 1 may also be referred to as an indexable cutting tool 1 with a working tool. The working tool 100 has an engaging shaft 101 and an operating portion 102 .

The engagement shaft 101 has a columnar shape centered on the central axis C and extends in the direction of the central axis. The engaging shaft 101 has a portion inserted into the female screw hole 11 and a portion protruding from the female screw hole 11 in the central axis direction. At least the lower end of the engaging shaft 101 has a non-circular cross-sectional shape perpendicular to the central axis C. As shown in FIG. The cross-sectional shape of the lower end portion of the engaging shaft 101 is, for example, polygonal, star-shaped, or the like.

A lower end portion of the engaging shaft 101 is inserted into the engaging hole 45 of the first screw member 40 from the central axis direction. The lower end portion of the engaging shaft 101 and the engaging hole 45 engage with each other in a state in which relative movement is allowed in the direction of the central axis and relative rotation about the central axis C is restricted. In this embodiment, the portion other than the lower end portion of the engaging shaft 101 is cylindrical.

The operating portion 102 is connected to the engaging shaft 101 and protrudes radially outward from the engaging shaft 101 . In this embodiment, the operation portion 102 is plate-shaped and extends radially outward from the engagement shaft 101 . A pair of plate surfaces of the operation unit 102 face the circumferential direction. When the operator rotates the operation part 102 in the circumferential direction around the central axis C, a high rotational torque can be applied to the first screw member 40 via the engagement shaft 101, and the first screw member 40 can be easily rotated. can be rotated to

Although not particularly illustrated, the operation portion 102 may have, for example, the handle shape of a screwdriver tool. In this case, the outer diameter dimension of the operating portion 102 is made larger than the outer diameter dimension of the engaging shaft 101 so that the operator can easily grip and rotate the operating portion 102 . Further, the outer peripheral surface of the operating portion 102 is appropriately provided with a non-slip shape or the like.

As shown in FIG. 4 , in a state in which the engagement shaft 101 and the engagement hole 45 are engaged, the operator operates the operation portion 102 to rotate the first screw member 40 in the circumferential direction. The screw member 40 is moved in the central axis direction by the action of the screws 14 and 43 . In addition, by rotating the first screw member 40 in the circumferential direction, the second screw member 50 screwed to the first screw member 40 can be screwed while being restricted from rotating in the circumferential direction by the restricting member 60. It is moved in the direction of the central axis by the actions of 44 and 54 .

[How to attach and detach the cutting insert]
Next, a method for attaching and detaching the cutting insert 20 to and from the holder 10, that is, a method for attaching and detaching the cutting insert 20 will be described.

First, a method of attaching the cutting insert 20 to (the insert attachment seat 12 of) the holder 10 will be described.
With the clamp piece 30 removed from the holder 10 , the fastening member 70 is inserted (screwed) into the female screw hole 11 of the holder 10 , and the cutting insert 20 is arranged in the insert mounting seat 12 .

Next, as shown in FIG. 5, the second screw member 50 is set to the open position. Specifically, when viewed from the top of the tool, the long axis of the oval shape of the first flange portion 52 and the long axis of the oval shape of the long hole 34 of the clamp piece 30 are aligned in the same direction. From this state, as shown in FIG. 6, the first flange portion 52 is inserted into the long hole 34 .
3, the projection 33 of the clamp piece 30 is inserted into the through hole 21 of the cutting insert 20, and the engaging portion 32 of the clamp piece 30 is inserted into the engaging groove 15 of the holder 10. As shown in FIG.

Next, the second screw member 50 in the open position shown in FIG. 6 is rotated around the central axis C (rotated by 90° in this embodiment), and as shown in FIG. 50 is the fastening position. Specifically, when viewed from the top of the tool, the long axis of the oval shape of the first flange portion 52 and the long axis of the long oval shape of the elongated hole 34 are arranged so as to cross each other (perpendicularly in this embodiment).
From this state, the restricting member 60 is screwed into the horizontal hole 16 with a wrench tool (not shown) to engage the contact portion 62 of the restricting member 60 with the engaging portion 55 of the second screw member 50 .

Next, as shown in FIG. 4, the engagement shaft 101 of the work tool 100 is inserted into the through hole 56 of the second screw member 50 from above, and the lower end of the engagement shaft 101 and the first screw member are inserted. 40 is engaged with the engaging hole 45. As shown in FIG.

From this state, when the operator rotates the operation unit 102 to one side in the circumferential direction (+θ side) around the central axis C, the first screw member 40 rotates to one side in the circumferential direction, thereby forming a right-hand thread (positive thread). ), the first screw member 40 moves downward in the central axis direction with respect to the female screw hole 11 .
Further, the second screw member 50 whose rotation around the central axis C is restricted by the restricting member 60 rotates the first screw member 40 to one side in the circumferential direction so that the screw 44 which is a left-hand thread (reverse thread) is rotated. , 54 move downward in the central axial direction with respect to the first screw member 40 .

Specifically, when the working tool 100 is rotated in one circumferential direction around the central axis C, the second screw member 50 changes the screw pitch of the screws 14 and 43 (P=1.75 mm in this embodiment) and the screw It is moved downward in the central axis direction with respect to the female screw hole 11 by the sum of the screw pitch (P=1.25 mm in this embodiment) of 44 and 54 (3 mm in this embodiment).

The first flange portion 52 of the second screw member 50 comes into contact with the clamp piece 30 from above while the operator rotates the work tool 100 in the circumferential direction one side (+θ side). When the operator further rotates the work tool 100 to one side in the circumferential direction, the first flange portion 52 presses the clamp piece 30 downward. Thereby, the clamp piece 30 is moved downward. At this time, the inclined surface 17 of the holder 10 and the slide surface 35 of the clamp piece 30 are brought into sliding contact with each other, so that the clamp piece 30 is also moved to the rear end side of the tool.

By moving the clamp piece 30 in this manner, the piece main body 31 presses the surface of the cutting insert 20 downward with its lower surface. Also, the projecting portion 33 of the clamp piece 30 presses the through hole 21 of the cutting insert 20 toward the rear end side of the tool.

Therefore, the cutting insert 20 is pressed downward by the clamp piece 30 and pulled into the tool rear end side to be fastened to the insert mounting seat 12 . Such a clamping method of the cutting insert 20 is clamping in two directions, and is called double clamping.

In this manner, the cutting insert 20 can be attached and fixed to the insert mounting seat 12 . After fixing the cutting insert 20 to the holder 10, the engaging shaft 101 is extracted from the engaging hole 45 and the through hole 56, and the working tool 100 is removed from the cutting tool.
After removing the working tool 100 , the cutting edge 22 of the cutting insert 20 turns (cuts) a work material (not shown).

In addition, the cutting insert 20 can be removed from (the insert mounting seat 12 of) the holder 10 by a procedure opposite to that described above.
When removing the cutting insert 20, first, as shown in FIG. The lower end and the engagement hole 45 of the first screw member 40 are engaged.

From this state, when the operator rotates the operation unit 102 to the other side in the circumferential direction (−θ side) around the central axis C, the first screw member 40 rotates to the other side in the circumferential direction, thereby forming a right-handed screw (positive screw). By the action of the screws 14 and 43 , the first screw member 40 moves upward in the central axis direction with respect to the female screw hole 11 .
Further, the second screw member 50 whose rotation around the central axis C is restricted by the restricting member 60 rotates the first screw member 40 to the other side in the circumferential direction, so that the screw 44 which is a left-hand screw (reverse screw) is rotated. , 54 move upward in the central axial direction with respect to the first screw member 40 .

Specifically, when the working tool 100 is rotated once in the other circumferential direction around the central axis C, the second screw member 50 changes the screw pitch of the screws 14 and 43 (P=1.75 mm in this embodiment) and the screw It is moved upward in the central axis direction with respect to the female screw hole 11 by the sum (3 mm in this embodiment) of the screw pitch of 44 and 54 (P=1.25 mm in this embodiment).

In the process in which the operator rotates the working tool 100 to the other circumferential side (−θ side), the second flange portion 53 of the second screw member 50 comes into contact with the clamp piece 30 from below. do. Specifically, the upper end surface of the second flange portion 53 contacts the portion of the lower surface of the bridge main body 31 located around the long hole 34 from below. When the operator further rotates the working tool 100 to the other side in the circumferential direction, the clamp piece 30 is pushed upward by the second flange portion 53 .

In this way, the downward pressing force of the cutting insert 20 by the clamp pieces 30 is released. Further, the pulling force of the clamp piece 30 toward the tool rear end side of the cutting insert 20 is also released.
Next, the engaging shaft 101 is extracted from the engaging hole 45 and the through hole 56, and the working tool 100 is removed from the cutting tool.

Next, a wrench tool (not shown) is used to rotate the regulating member 60 around its central axis and retract it radially outward in the horizontal hole 16 , so that the contact portion 62 of the regulating member 60 and the second screw member 50 is released from the engagement with the engaging portion 55.

Next, the second screw member 50 at the fastening position shown in FIG. 7 is rotated around the central axis C (rotated by 90° in this embodiment), and as shown in FIG. Let 50 be the open position. Specifically, when viewed from the top of the tool, the long axis of the oval shape of the first flange portion 52 and the long axis of the oval shape of the elongated hole 34 are arranged so as to be parallel to each other.
As a result, as shown in FIG. 5 , the long hole 34 can pass through the first flange portion 52 , and the clamp piece 30 and cutting insert 20 can be removed from the holder 10 .

[Effects of this embodiment]
According to the indexable cutting tool 1 of the present embodiment described above, when the operator rotates the first screw member 40 around the central axis C, for example, by one rotation with the working tool 100, the second screw member 50 The holder 10 , along the female screw hole 11 in the central axis direction.
Therefore, the clamp piece 30 can be pressed by the second screw member 50 while the amount of rotation of the working tool 100 is kept small, and the cutting insert 20 can be pressed and fixed to the insert mounting seat 12 via the clamp piece 30 .

Specifically, unlike the present embodiment, for example, compared to the conventional case where the clamp piece is fastened to the holder using a single clamp screw, according to the present embodiment, the work tool 100 is rotated around the central axis C. The clamp piece 30 can be fastened to the holder 10 by the fastening member 70 while keeping the number of rotations and the rotation angle small.

Therefore, according to the present embodiment, workability is good when attaching and detaching the cutting insert 20 to and from the holder 10 . Since the attachment/detachment operation of the cutting insert 20 is completed easily and in a short time, the workability when using the indexable cutting tool 1 can be further improved. In addition, since the attachment/detachment work is facilitated, the cutting insert 20 can be fixed to the holder 10 with more stable attachment accuracy.

Further, in this embodiment, the second screw member 50 is rotatable around the central axis C between the open position and the fastening position.
In this case, by setting the second screw member 50 to the open position, the first flange portion 52 can be inserted into the long hole 34 of the clamp piece 30, and the clamp piece 30 can be easily attached and detached. Also, when the second screw member 50 is at the fastening position, the first flange portion 52 extends in a direction intersecting with the extending direction of the long hole 34 and overlaps the clamp piece 30 when viewed from the central axis direction. Thereby, the clamp piece 30 can be stably pressed by the first flange portion 52 . As a result, the clamp piece 30 can more stably fix the cutting insert 20 to the holder 10 .

Further, in this embodiment, the second screw member 50 has the second flange portion 53 that can contact the clamp piece 30 from the female screw hole 11 side in the central axis direction.
In this case, when the clamp piece 30 is removed from the holder 10 , the second flange portion 53 contacts the clamp piece 30 from the female screw hole 11 side (lower side), thereby moving the clamp piece 30 away from the holder 10 . can be pressed. Therefore, the clamp piece 30 can be removed from the holder 10 more easily.

Further, in this embodiment, the disk portion 42 of the first screw member 40 has an engagement hole 45 that can be engaged with the working tool 100 .
In this case, by engaging the working tool 100 with the engagement hole 45 of the first screw member 40 and rotating it around the central axis C, the first screw member 40 can be easily and quickly rotated. As a result, the workability when exchanging the cutting insert 20 can be further improved.

Moreover, in this embodiment, the second screw member 50 has a through hole 56, and the through hole 56 overlaps with the engaging hole 45 when viewed from the central axis direction.
In this case, the working tool 100 can be engaged with the engaging hole 45 through the through hole 56 of the second screw member 50 . Therefore, the operator can rotate the first screw member 40 by using the work tool 100 from the clamp piece 30 side (upper side) of the holder 10, and workability can be further enhanced.

Further, in the present embodiment, the regulating member 60 is inserted into the horizontal hole 16 of the holder 10 , and the tip portion (the radially inner end portion) of the regulating member 60 engages with the engaging portion 55 of the second screw member 50 . .
In this case, the rotation of the second screw member 50 around the central axis C can be stably restricted by a simple structure.

[Other configurations included in the present invention]
It should be noted that the present invention is not limited to the above-described embodiments, and as described below, changes in configuration and the like are possible without departing from the scope of the present invention.

In the above-described embodiment, the screw pitch (first screw pitch) of the first male screw 43 and the holder female screw 14 is greater than the screw pitch (second screw pitch) of the second male screw 54 and the first female screw 44. I gave a big example, but it's not limited to this. That is, even if the screw pitch (first screw pitch) of the first male screw 43 and the holder female screw 14 is smaller than the screw pitch (second screw pitch) of the second male screw 54 and the first female screw 44, good. Alternatively, the first thread pitch and the second thread pitch may be the same.

In the above-described embodiment, when the cutting tool is viewed from above along the central axis direction, one side in the circumferential direction (+θ side) is the clockwise direction, and the other side in the circumferential direction (−θ side) is the counterclockwise direction. An example of the direction is given, but the present invention is not limited to this.
That is, when the cutting tool is viewed from above along the direction of the central axis, one side in the circumferential direction may be counterclockwise and the other side in the circumferential direction may be clockwise. In this case, the holder female thread 14 and the first male thread 43 are left-hand threads (reverse threads), and the first female thread 44 and the second male thread 54 are right-hand threads (normal threads). A function and effect similar to those of the morphology can be obtained.

According to the indexable cutting tool of the present invention, workability is good when attaching and detaching the cutting insert to and from the holder. Therefore, it has industrial applicability.

DESCRIPTION OF SYMBOLS 1... Blade-tip indexable cutting tool 10... Holder 11... Female screw hole 12... Insert mounting seat 13... Opening 14... Holder female screw 16... Lateral hole 20... Cutting insert 56... Through hole 30... Clamp piece 34... Long hole 40 First screw member 41 Cylindrical part 42 Disk part 43 First male screw 44 First female screw 45 Engagement hole 50 Second screw member 52 First flange 53 Second flange 54 Second male screw 55 Engaging portion 60 Restricting member 70 Fastening member 100 Working tool C Central axis

Claims (6)

a holder having an insert mounting seat;
a cutting insert detachably attached to the insert mounting seat;
a clamp piece for fixing the cutting insert to the insert mounting seat;
a fastening member that fastens the clamp piece to the holder;
a regulating member provided in the holder and in contact with a part of the fastening member;
The holder has a female screw hole into which the fastening member is screwed,
The female screw hole is
an opening that opens toward the clamp piece;
a holder female screw that spirally extends away from the clamp piece in the central axis direction toward one side in the circumferential direction around the central axis of the female screw hole;
The fastening member is
a cylindrical first screw member extending in the central axis direction;
a second screw member inserted inside the first screw member;
The first screw member is
a first male screw disposed on the outer peripheral surface of the first screw member and screwed with the holder female screw;
a first female screw disposed on the inner peripheral surface of the first screw member and spirally extending toward the one side in the circumferential direction so as to approach the clamp piece in the central axis direction;
The second screw member is
a second male screw disposed on the outer peripheral surface of the second screw member and screwed with the first female screw;
a first flange portion that can contact the clamp piece from a side opposite to the female screw hole in the central axis direction;
The restricting member restricts rotation of the second screw member about the central axis and allows movement in the central axis direction.
Indexable cutting tool. The clamp piece has an elongated hole penetrating the clamp piece in the central axis direction,
the long hole extends in a direction orthogonal to the central axis when viewed from the central axis direction,
The second screw member is
an open position in which the first flange portion can pass through the long hole in the central axis direction;
It is rotatable around the central axis between a fastening position where the first flange portion and the clamp piece overlap when viewed from the central axis direction,
The indexable cutting tool according to claim 1. The second screw member further has a second flange portion that can contact the clamp piece from the female screw hole side in the central axis direction,
The indexable cutting tool according to claim 1 or 2. The first screw member is
a cylindrical portion having a cylindrical shape centered on the central axis and having the first male screw formed on the outer peripheral surface;
a disk portion integrally formed with the cylindrical portion and extending in a direction perpendicular to the central axis;
The disc portion extends in the direction of the central axis and has an engagement hole that can be engaged with a working tool.
The indexable cutting tool according to any one of claims 1 to 3. The second screw member has a through hole penetrating the second screw member in the central axis direction,
The through hole overlaps the engagement hole when viewed from the central axis direction,
The indexable cutting tool according to claim 4. the holder has a lateral hole extending toward the female screw hole from a direction intersecting the central axis and into which the restricting member is inserted;
The second screw member has an engaging portion facing the lateral hole,
a distal end portion of the restricting member is engaged with the engaging portion;
The indexable cutting tool according to any one of claims 1 to 5.

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