JP6726410B2 - Cutting inserts and rotary cutting tools - Google Patents

Description

The present invention relates to cutting inserts and rotary cutting tools.

In order to attach the cutting insert to the body, it is known to provide the cutting insert with a tapered surface and bring this tapered surface into contact with the clamp part of the body.

For example, in Patent Document 1, the end portion of the base metal 2 to which the cutting edge tip 3 is attached is configured such that the thickness becomes larger toward the center of rotation, and the end portion of the base metal 2 is clamped by the clamp mechanism 14. A technique is described for fixing the cutting insert to the milling cutter by clamping it with.

Further, Patent Document 2 describes a self-clamp type end mill in which a plurality of peripheral surface chips A are attached at a predetermined interval in the axial direction at an intermediate portion in the rotational axis direction. In this end mill, in order to appropriately fix the peripheral surface chip A, the engaging groove 10 for mounting the peripheral surface chip A is provided with a dovetail groove that is wider than the groove width of the opening edge 13 of the engaging groove 10. At the same time, the engaging groove 10 is formed so that the end portion of the opening edge 13 is narrower than the starting end portion thereof. Then, it is described that the peripheral tip A is fixed to the side surface of the end mill by making the peripheral tip A trapezoidal so as to engage with the engaging groove 10.

JP, 2016-7663, A JP, 2011-20235, A

However, the milling cutter described in Patent Document 1 merely presses the cutting insert in the rotational direction by using the clamp mechanism 14a. Therefore, in order to fix the cutting insert also in the rotation axis direction, it is necessary to make the clamp mechanism 14a large. This document describes a configuration in which a large clamp mechanism 14a is provided on the outer peripheral portion together with a cutting insert. However, as described in this document, for example, a small-diameter end mill with a limited outer peripheral area and a large-diameter cutter with a limited circumferential spacing between cutting inserts due to the large number of blades, etc. It is difficult to apply various technologies.

Further, in the end mill described in Patent Document 2, the engaging groove 10 for fixing the peripheral tip A must be provided with a dovetail groove. Therefore, it is difficult to apply the technique described in this document to fix the cutting insert attached to the tip of the rotary cutting tool.

Therefore, the present invention is a cutting insert that can be attached to the tip of the body of a rotary cutting tool and that can be pressed against the body in any of the rotation direction, the rotation axis direction, and the radial direction, and An object is to provide a rotary cutting tool provided with such a cutting insert.

The cutting insert according to one aspect of the present invention is attached to a body that rotates about a rotation axis. Then, a first surface that faces the direction of rotation and that has a first clamp surface that contacts the body, and a second surface that faces the opposite direction to the first surface and that has a second clamp surface that contacts the body, A third surface facing radially outward, a fourth surface facing radially inward of the rotating shaft, a rotating shaft direction facing toward the body tip side, and a fifth surface facing the rotating shaft, A sixth surface facing the base end side of the body, and a cutting edge provided at least in a connecting portion connecting the first surface and the third surface are provided. Then, in the cross section perpendicular to the rotation axis, the second clamp surface is inclined with respect to the first clamp surface such that the distance between the first clamp surface and the second clamp surface increases as the distance from the cutting edge increases, and In addition, the fourth surface is provided with an inclined surface in which the distance from the rotation axis decreases as the distance to the base end side of the body increases.

A rotary cutting tool according to an aspect of the present invention includes a body that rotates about a rotation axis and a cutting insert attached to the body. The cutting insert has a first surface having a first clamping surface facing the direction of rotation and abutting against the body, and a second surface having a second clamping surface facing the direction opposite to the first surface and abutting against the body; The third surface facing the radial outer side of the shaft, the fourth surface facing the radial inner side of the rotary shaft, the fifth surface facing the rotary shaft direction toward the body tip side, and the rotary shaft direction facing the rotary shaft direction. And a cutting edge provided at least in a connecting portion that connects the first surface and the third surface, the first clamp being provided in a cross section perpendicular to the rotation axis. The second clamp surface is inclined with respect to the first clamp surface such that the distance between the surface and the second clamp surface increases as the distance from the cutting edge increases. Further, the fourth surface approaches the rotation axis as it advances toward the body proximal end side. Further, in the cross section parallel to the rotation axis, the second clamp surface is inclined with respect to the first clamp surface so that the distance between the first clamp surface and the second clamp surface changes according to the position on the rotation axis. May be.

Further, the cutting insert according to one aspect of the present invention is attached to the tip of a body that rotates about a rotation axis. The surface of the cutting insert facing the rotation axis is inclined so as to approach the rotation axis toward the base end side of the body. Further, the cutting insert has a clamp surface that abuts on the body and faces the rotation direction, and a clamp surface that abuts on the body and faces the opposite direction to the rotation direction. The two clamping surfaces may then be inclined in a cross section parallel to the axis of rotation and passing through these two surfaces. A cross section perpendicular to the axis of rotation and passing through these two planes has an inclined relationship. One of the clamp surfaces may be parallel to the rotation axis or inclined. In the cross section parallel to the axis of rotation and passing through these two surfaces, the distance between the clamp surfaces becomes smaller toward the base end side of the body, and in the section perpendicular to the axis of rotation and passing through these two surfaces, It is preferable that the distance between the clamp surfaces decreases as the distance from the axis increases.

Further, the cutting insert according to the aspect of the present invention can be clamped to the body. And a first surface having a first clamping surface, a second surface facing the opposite direction to the first surface and having a second clamping surface, and a third surface connecting the first clamping surface and the second clamping surface. , A fourth surface facing the direction opposite to the third surface and connecting the first clamp surface and the second clamp surface, a first clamp surface, a second clamp surface, a third clamp surface, and a fourth clamp surface And a fifth surface facing the tip side of the body when clamped to the body, facing in a direction opposite to the fifth surface, and having a first clamp surface, a second clamp surface, and a third clamp surface. A cutting edge which is connected to a fourth clamping surface and is provided at least in a connecting portion which connects the sixth surface facing the base end side of the body when clamped to the body and the first surface and the third surface. And Further, in the cross section perpendicular to the cutting edge, the second clamping surface is inclined with respect to the first clamping surface such that the distance between the first clamping surface and the second clamping surface increases as the distance from the cutting edge increases. The fourth surface is provided with an inclined surface whose distance from the rotation axis becomes smaller as it advances toward the body proximal end side. Moreover, the second clamp surface may be inclined with respect to the first clamp surface in a cross section passing through the first clamp surface, the second clamp surface, the fifth surface, and the sixth surface.

Here, the cutting edge refers to a portion that is provided in a substantially linear shape among the portions where the cuttable blade is formed. However, the cutting edge may be curvedly formed at a fine level. The cross section perpendicular to the cutting edge means a cross section perpendicular to a straight line approximating the portion where the cutting edge is formed. In addition, the cross section including the cutting edge refers to a cross section including a straight line that approximates a portion where the cutting edge is formed. In such a cross section that passes through the first clamp surface and the second clamp surface, the distance between the straight lines or the curved lines respectively showing the first clamp surface and the second clamp surface may change significantly. For example, both are inclined.

Further, when such a cutting insert is attached to the body, a surface inclined so as to approach the rotation axis toward the base end side of the body is provided with a member such as a screw or a wedge having the rotation axis of the body as an axis. It is desirable to press in the base end direction and the radial direction of the rotary shaft. At this time, the surface inclined so as to approach the rotation axis toward the base end side of the body may be a flat surface, or may be a curved surface having a circle having the rotation axis as a center in its cross section.

Further, by providing cutting inserts having the same structure at different positions in the circumferential direction of the body, a plurality of cutting inserts may be simultaneously pressed by one member provided on the rotary shaft.

Perspective view, front view and right side view of the cutting insert 10. Plan view, bottom view, left side view and rear view of the cutting insert 10. End mill 100 perspective view Perspective view of male screw 60 The figure which looked at the end mill 100 from the tip direction of the rotating shaft AX. Perspective view of a modified example using left and right screws 67 A perspective view, a front view and a right side view of a cutting insert 70 according to a modified example. Plan view, bottom view, left side view and rear view of the cutting insert 70. A perspective view, a front view and a right side view of a cutting insert 90 according to a modified example. Plan view, bottom view, left side view and rear view of the cutting insert 90.

[First Embodiment]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that duplicate description of elements having the same or equivalent functions and structures will be omitted. Further, the following embodiments are exemplifications for explaining the present invention and are not intended to limit the present invention only to the embodiments. Further, the present invention can be variously modified without departing from the gist thereof.

FIG. 1A is a perspective view of the cutting insert 10 according to the present embodiment. In addition, FIGS. 1B and 1C show a fifth example in which the cutting insert 10 faces the tip direction of the cutter body 50, which is the direction of the rotation axis AX when the cutting insert 10 is attached to the cutter body 50 (FIG. 3 ). It is a front view when it sees from the direction which opposes the surface 12, and a right side view when it sees from the direction which opposes the 3rd surface 16 which faces a radial direction outer side. 2(a), (b), (c) and (d) respectively show a plan view and a rotation direction when the cutting insert 10 is viewed from a direction facing the first surface 14 facing the rotation direction. And a bottom view when viewed from the direction facing the second surface 18 facing the opposite side, a left side view when viewed from the direction facing the fourth surface 20 facing the radially inner side, and the opposite of the rotation axis AX. It is a rear view when it sees from the direction which faces the 6th surface 22 which faces the base end side of the cutter body 50 which is a direction. In addition, FIG. 3 is a perspective view of the end mill 100 in which the cutting insert 10 ′ and the cutting insert 10 ″ having the same structure as the cutting insert 10 are attached to the cutter body 50 together with the cutting insert 10.

As shown in FIGS. 1 and 2, the cutting insert 10 includes a second surface 18 and a third surface 16, a fourth surface 20, a fifth surface 12, and a sixth surface 22 which are connected to the second surface 18. And a first surface 14 facing away from the second surface 18.

Further, for example, as shown in FIG. 1A, a main cutting edge 24A is formed at the intersecting ridge line portion connecting the first surface 14 and the third surface 16, and the first surface 14 and the fifth surface 12 are formed. A sub-cutting edge 24B is formed at the intersecting ridge line portion connecting with. Further, a corner blade 24C formed in an arc shape is formed so as to be smoothly connected to the main cutting edge 24A and the sub cutting edge 24B, respectively.

As shown in FIG. 3, when the cutting insert 10 is attached to the tip of the cutter body 50, the fifth surface 12 is in the direction of the rotation axis AX of the cutter body 50, and the tip side of the cutter body 50 is fixed. Turn. The sixth surface 22 (FIG. 2D) facing the opposite direction of the fifth surface 12 is the direction of the rotation axis AX and faces the base end side of the cutter body 50. Further, for example, the first surface 14 shown in FIG. 1B faces the direction in which the cutter body 50 rotates, and the second surface 18 generally faces the direction opposite to the first surface 14. Further, the third surface 16 faces the outer side in the radial direction of a circle centered on the rotation axis AX of the cutter body 50, and the fourth surface 20 faces the inner side in the radial direction. The third surface 16, the fourth surface 20, the fifth surface 12 and the sixth surface 22 are provided between the second surface 18 and the first surface 14 and connect the second surface 18 and the first surface 14 to each other. However, these surfaces do not necessarily have to be directly connected to each other. For example, FIG. 1A shows that the fifth surface 12 and the third surface 16 are connected via another curved surface. Further, these surfaces may be smoothly connected to each other to form one continuous surface. Further, as shown in the first surface 14, the surface to which one reference numeral is attached as the surface facing the predetermined direction may be composed of a plurality of discontinuous flat surfaces or curved surfaces.

The second surface 18 is a surface facing the opposite side to the rotation direction of the cutter body 50 when the cutting insert 10 is attached to the cutter body 50. As shown in FIG. 2B, the second surface 18 has a length on one side on the sixth surface 22 side rather than a length on one side on the fifth surface 12 side when viewed from the opposite direction. Has a substantially trapezoidal shape that is slightly larger. The second surface 18 includes a clamp surface (an example of a “second clamp surface”) that is a plane parallel or substantially parallel to the rotation axis AX, and when the cutting insert 10 is attached to the cutter body 50, The clamping surface abuts the surface of the holder body 52″ (FIG. 3) of the cutter body 50 that faces the direction of rotation.

On the other hand, the first surface 14 facing the opposite direction to the second surface 18 is a surface facing the rotation direction of the cutter body 50 when the cutting insert 10 is attached to the cutter body 50. Therefore, the first surface 14 includes a surface that functions as a rake surface for the main cutting edge 24A, the sub cutting edge 24B, and the corner blade 24C. As shown in FIG. 2A, the first surface 14 is configured to have a flat surface or a flat shape defined by four sides, and the length of one side on the fifth surface 12 side is closer to the sixth surface 22 side. It is formed so as to be wider toward the sixth surface 22 side so that the length of one side becomes larger. The first surface 14 is a clamp surface that abuts a surface of the holder body 52 (FIG. 3) of the cutter body 50 facing the opposite rotation direction when the cutting insert 10 is attached to the cutter body 50 (“first surface”). Clamping surface”).

Then, when the cutting insert 10 is attached to the cutter body 50, the surface of the holder portion 52 facing the opposite direction to the rotation direction abuts the clamping surface of the first surface 14, and the rotation direction of the holder portion 52″. By contacting the clamping surface of the second surface 18 with the surface facing toward, the cutting insert 10 can be suitably fixedly supported to the cutter body 50 in the rotational direction.

In the present embodiment, most of the area of the first surface 14 excluding the rake surface corresponds to the clamp surface that contacts the holder portion 52 of the cutter body 50, and the tip of the cutter body 50 of the second surface 18 is provided. Most of the side region (for example, a half or more region) corresponds to the clamp surface that abuts the holder portion 52″ of the cutter body 50. By thus increasing the area of the area in contact with the cutter body 50 (including the case of making point contact at a plurality of points in the area), the cutting insert 10 can be stably supported. However, the present invention is not limited to this, and it may be configured such that only a partial region (for example, a half or less region) of the second surface 18 or the first surface 14 abuts the cutter body 50. Good.

In the cutting insert 10 according to the present embodiment, further, the first surface 14 and the clamp surface included in the first surface 14 are also cross-sections perpendicular to the rotation axis AX with respect to the second surface 18 and the clamp surface included therein. Even in a cross section parallel to the rotation axis AX, it is inclined. Hereinafter, such a configuration will be described.

First, as shown in FIG. 1B, as the first surface 14 moves away from the main cutting edge 24A and the third surface 16 and approaches the fourth surface 20 facing the rotation axis AX, the first surface 14 becomes the second surface 18. Is inclined with respect to the second surface 18 so as to increase the distance (or increase the thickness of the cutting insert 10 defined as the distance between the first surface 14 and the second surface 18). ..

In other words, the distance between the two clamping surfaces of the cutting insert 10 that is gripped in the rotational direction by the cutter body 50 is provided so as to decrease as the distance from the rotation axis AX increases.

Not only in the front view shown in FIG. 1(b), but also in a cross section perpendicular to the rotation axis AX and passing through the first surface 14 and the second surface 18, there is a similar relationship. The included clamping surface is inclined with respect to the second surface 18 as well as the clamping surface included therein. However, it is not necessary to have such an inclined relationship in the portion that does not include the clamp surface.

Here, the second surface 18 and the first surface 14 do not necessarily have to be flat surfaces, and may be formed of curved surfaces. For example, in a cross section that is perpendicular to the rotation axis AX and passes through the clamp surface of the first surface 14 and the clamp surface of the second surface 18, the curve becomes such that the distance between the two becomes smaller as the distance from the rotation axis AX increases. The second surface 18 and the first surface 14 may be configured.

The inclination angle of the first surface 14 with respect to the second surface 18 does not have to be constant regardless of the position on the rotation axis AX. For example, the inclination angle of the first surface 14 with respect to the second surface 18 may be smaller and closer to parallel as the base end of the cutter body 50 is closer.

On the other hand, also in the direction parallel to the rotation axis AX, that is, in the cross section passing through the first surface 14, the second surface 18, the fifth surface 12 and the sixth surface 22, the first surface 14 and the clamp surface included therein. Are inclined with respect to the second surface 18 and the clamping surface contained therein. Therefore, in the cross section which is parallel to the rotation axis AX and which passes through the first surface 14 and the second surface 18, the straight line forming the first surface 14 is not parallel to the straight line forming the second surface 18. Here, the first surface 14 and the second surface 18 may be inclined such that the distance between the first surface 14 and the second surface 18 becomes larger or the distance becomes smaller toward the base end direction of the rotation axis AX. In the case of the cutting insert 10 according to the first embodiment, in FIG. 2D, one side of the first surface 14 on the sixth surface 22 side is closer to the second surface 18 than one side of the first surface 14 on the fifth surface 12 side. As also shown from the above, the first surface 14 is inclined such that the distance between the first surface 14 and the second surface 18 becomes smaller toward the base end direction of the rotation axis AX. In this way, when the distance between the first surface 14 and the second surface 18 is made smaller toward the base end direction of the rotation axis AX, the cutting insert 10 can be used in the case of machining for increasing the axial rake angle. In addition, since a force of pulling out from the cutter body 50 is applied, the cutter body 50 can favorably fix and support the cutting insert 10 as compared with the opposite case. However, the present invention is not limited to this, and for example, the distance between the first surface 14 and the second surface 18 may be constant regardless of the position on the rotation axis AX.

According to such a cutting insert 10, when it is attached to the cutter body 50, the clamping surface of the first surface 14 that comes into contact with the surface of the holder portion 52 facing the direction opposite to the rotation direction, and the holder portion 52″. The clamping surface of the second surface 18 that abuts the surface of the cutter body 50 that is in contact with the surface facing the rotation direction is inclined both in the direction away from the main cutting edge 24A and in the direction in which the main cutting edge 24A is formed. The cutting insert 10 can be pressed toward the cutter body 50 in any of the rotation direction of, the direction of the rotation axis AX, and the radial direction perpendicular to the rotation axis AX. Therefore, the cutter body 50 can suitably fix and support the cutting insert 10.

Although each clamp surface is preferably a flat surface from the viewpoint of manufacturing cost, it is not limited to this and may be a curved surface having the above-described relationship. The second surface 18 may be a plane parallel to the rotation axis AX when attached to the cutter body 50, but may be inclined with respect to the rotation axis AX as described later.

Next, the fourth surface 20 of the cutting insert 10 will be described. As described above, the fourth surface 20 is a radially inner side, that is, a surface facing the rotation axis AX when attached to the cutter body 50. As shown in FIG. 2C, the fourth surface 20 maintains substantially the same width from the fifth surface 12 to the sixth surface 22 when viewed from the opposite direction. In the vicinity of the connection portion with the sixth surface 22, the width is chamfered so that the width becomes smaller. Further, as shown in FIGS. 1B, 2A, and 2B, the fourth surface 20 approaches the sixth surface 22 from the fifth surface 12, that is, the base of the cutter body 50. It is gently inclined with respect to the rotation axis AX such that the distance to the rotation axis AX becomes smaller as it advances toward the end side.

The fifth surface 12 and the third surface 16 are surfaces that function as flanks for the sub cutting edge 24B and the main cutting edge 24A, respectively. It does not need to be configured in a flat shape, and for example, a curved surface or a step-shaped (step-shaped) flank may be provided.

Hereinafter, a configuration for mounting the cutting insert 10 and the cutting insert 10′ and the cutting insert 10″ having the same structure as the cutting insert 10 on the cutter body 50 will be described with reference to FIGS. 3, 4, and 5. FIG. 4 is a perspective view of a male screw 60 for fixing such cutting inserts 10, 10 ′ and 10 ″ to the cutter body 50. FIG. 5 is a front view of the end mill 100 seen from the direction of the rotation axis AX.

As shown in FIG. 4, the male screw 60 includes a screw portion 62 and a head portion 64. In addition, in the present embodiment, a portion of the head portion 64 provided at the connection portion with the screw portion 62 is referred to as a neck portion 66 (also referred to as a taper seat surface portion) in the present embodiment. The screw portion 62 is formed with a screw for screwing with a female screw with the axis AX2 as the central axis. The head 64 has a hole for rotating the male screw 60 with a wrench. The neck portion 66 is provided with a conical side surface that is gently inclined from the large-diameter head portion 64 to the small-diameter screw portion 62 and faces the screw portion 62 side with the axis AX2 as an axis. Here, the inclination angle of the cone is set so as to be substantially the same as the inclination angle of the fourth surface 20 with respect to the rotation axis AX. When the male screw 60 is screwed with a female screw formed on the cutter body 50 with the rotation axis AX as the central axis and advances in the proximal direction of the cutter body 50, the side surface provided on the neck portion 66 has the side surface of the cutting insert 10. The cutting inserts 10, 10' and 10'' are fixed relative to the cutter body 50 by abutting the fourth surface 20 and corresponding surfaces of the cutting inserts 10' and 10'', respectively.

As shown in FIG. 3, at the tip of the cutter body 50 in the rotation axis AX direction, three holder parts 52, 52′ and 52″ having the same structure are formed at equal intervals in the rotation direction. There is.

Each holder part 52, 52 ′ and 52 ″ has a surface facing the rotation direction of the cutter body 50 and a surface facing the opposite direction.

As shown in FIGS. 3 and 5, the surface of the holder portion 52 that faces the direction opposite to the rotation direction is the same as the clamping surface (an example of the “first clamping surface”) included in the first surface 14 of the cutting insert 10. The surface that abuts and faces the rotation direction of the holder portion 52 ″ abuts a clamp surface (an example of a “second clamp surface”) included in the second surface 18 of the cutting insert 10. When the cutting insert 10 is attached to the cutter body 50, the surface facing the rotation direction of the holder portion 52 has a first surface so as to be substantially parallel to the first clamp surface included in the first surface 14. Similar to the surface 14, the cross section that is parallel to the rotation axis AX and passes through the clamp surface included in the first surface 14 and the clamp surface included in the second surface 18 is also inclined in the cross section perpendicular to the rotation axis AX. It becomes a tapered surface. Further, the surface of the holder portion 52″ facing the rotation direction is provided parallel to the surface including the rotation axis AX so as to be substantially parallel to the second clamp surface included in the second surface 18.

In this way, after inserting the cutting inserts 10, 10′ and 10″ into the regions between the holder portions 52, 52′ and 52″, respectively, the male screw 60 is used with the rotation axis AX as the central axis. It is screwed with the female screw formed on 50. The fourth surface 20 of the cutting insert 10 and the corresponding surface of the cutting inserts 10′ and 10″ and the side surface of the cone provided on the neck portion 66 of the male screw 60 are substantially parallel to each other in the cross section including the rotation axis AX. Therefore, as the male screw 60 advances on the rotation axis AX, the side surface of the cone provided on the neck portion 66 and the corresponding surface of the fourth surface 20 of the cutting insert 10 and the cutting inserts 10 ′ and 10 ″ are substantially formed. Approaching while keeping parallel.

Then, with sufficient force, the side surface of the cone provided in the neck portion 66 and the corresponding surface of the fourth surface 20 of the cutting insert 10 and the cutting inserts 10 ′ and 10 ″ are brought into contact with each other, whereby the cutting insert 10 10' and 10'' are fixed to the cutter body 50. At this time, the cutting inserts 10, 10 ′ and 10 ″ are acted on in the direction opposite to the direction of the rotation axis AX as well as in the radial direction. On the other hand, in the inclined surface of the holder portion 52, the distance between the holder portion 52″ and the adjacent holder portion 52″ becomes narrower toward the outer side in the radial direction, and becomes narrower toward the base end side opposite to the rotation axis AX. Thus, the first surface 14 of the cutting insert 10 is suitably pressed against the holder portion 52. The cutting inserts 10 ′ and 10 ″ are similarly fixed to the cutter body 50.

According to the rotary tool such as the end mill described above, the surface provided in the opposite direction to the surface of the cutting insert facing the rotational direction is inclined in two directions. By bringing the cutting insert into contact with the body, the cutting insert can be more stably fixed and supported. In particular, for example, a small-diameter end mill having a tool diameter of 8 mm exerts a large centrifugal force based on high-speed rotation in order to improve the cutting speed, and thus can be suitably applied to such a small-diameter end mill. However, the present invention can also be applied to a rotary tool such as a milling cutter.

In addition, a female screw is provided on the rotary shaft of the body, and the side faces of the male screw screwed into the female screw are brought into contact with two or more cutting inserts provided on the radially outer side at the same time to fix these cutting inserts. Will be possible. Therefore, it is possible to fix a larger number of cutting inserts as compared with a conventional rotary tool having the same diameter that requires a clamp component on the outer peripheral side of the tool. As a result, it is possible to increase the number of blades, provide a highly efficient rotary tool, and increase the thickness of the holder for holding the cutting insert in the rotational direction to improve the tool rigidity. Become.

Further, compared with the conventional rotary tool that requires a clamp component on the outer peripheral side of the tool, the structure is simple, so that the manufacturing cost can be reduced.

The second surface 18 may be a plane parallel to the rotation axis AX when attached to the cutter body 50, or may be inclined with respect to the rotation axis AX. For example, the second surface 18 may be slightly inclined with respect to the rotation axis AX toward the fourth surface 20, and may be configured to be closer to the rotation axis AX as it approaches the base end of the rotation axis AX. With this configuration, the cutting insert 10 can be taken out by slightly loosening the male screw 66. In addition, the expression that the distance between a certain surface and another surface changes in accordance with the progress in a predetermined direction in a predetermined cross section includes the case where a part of the area has a constant distance.

Further, the first surface 14 and the clamp surface included therein may be attached to the cutter body 50 so as to be parallel to the rotation axis AX. In this case, the rigidity at the time of clamping becomes higher than that when the rigidity is not parallel. However, the first surface 14 and the clamp surface included therein may not be parallel to the rotation axis AX.

For example, when a positive axial rake is provided, the first surface 14 and the clamp surface included therein are inclined with respect to the rotation axis such that the first surface 14 and the clamp surface included therein advance in the rotational direction as the tip surface of the cutter body 50 advances. Is attached as. In this case, the cutting resistance can be reduced.

On the other hand, in the case of providing a negative axial rake, the first surface 14 and the clamp surface included therein are arranged with respect to the rotation axis so that the first surface 14 and the clamp surface included therein advance in the rotation direction toward the base end side of the cutter body 50. It is attached so that it can be tilted. In this case, the cutting resistance is reduced and the tip of the cutting insert 10 is less likely to be chipped.

[Modification 1]
Hereinafter, a modified example in which the cutting inserts 10, 10 ′ and 10 ″ are fixed to the cutter body 50 using the left and right screws 67 and the wedge 68 instead of the male screw 60 will be described. FIG. 6 is a perspective view showing such an end mill 100'. Note that description of elements having the same or similar configurations or functions is omitted.

As shown in FIG. 6, the left and right threads 67 are provided at both ends with a right thread portion 67B in which a right thread is formed and a left thread portion 67A in which a left thread is formed. Further, the wedge 68 is provided with a conical surface 68A narrowing in the base end direction of the rotation axis AX and a flat surface 68B for preventing rotation. The number of the planes 68B can be set as appropriate, but for example, the three planes 68B can be formed at equal intervals in the circumferential direction.

Then, the right-hand thread 67B is screwed into a female thread formed around the rotation axis AX of the cutter body 50, and the left-right thread 67 is rotated while the wedge 68 is screwed into the left-hand thread 67A. As a result, the wedge 68 can be advanced more in the base end direction of the rotation axis AX than in the case where a normal screw is used. If the pitch of the right threaded portion 67B and the pitch of the left threaded portion 67A are the same, by using the left and right threads 67, the amount of progress for the same amount of rotation can be increased compared to the case of a normal screw. Can be doubled. Therefore, the replacement time of the cutting insert 10 can be shortened. The wedge 68 is provided with a not-shown detent structure for preventing the wedge 68 from rotating together with the left and right screws 67 when loosened.

In this way, by advancing the wedge 68 in the proximal direction of the rotation axis AX, the three planes 68B of the wedge 68 are moved to the fourth surface 20 of the cutting insert 10 and the fourth surface 20B of the cutting insert 10′ and the cutting insert 10″. The cutting inserts 10, 10 ′ and 10 ″ can be fixedly supported on the cutter body 50 by abutting on the surfaces corresponding to the surfaces 20, respectively. At this time, the anti-rotation flat surface 68B and the fourth surface 20 of the cutting insert 10 can be brought into surface contact with each other, so that the clamp rigidity can be increased.

According to such a modification, the cutting insert 10 and the like can be simultaneously fixed with a small number of rotations by screwing the wedge 68 and the left-hand threaded portion 67A.

Various methods can be applied as a method of pressing the cutting insert against the cutter body. For example, a conical wedge may be used. Further, the pressing is not limited to the conical surface, and other curved surfaces (for example, a curved surface that is a circle in a section perpendicular to the rotation axis is partially provided), or the rotation axis direction of the cutter body or its rotation direction. The cutting member may be fixed by advancing a fixing member having a stepped surface toward the base end direction of the rotary shaft.

[Modification 2]
Hereinafter, a cutting insert 70 which is a modified example of the cutting insert 10 will be described with reference to the drawings. It should be noted that the description of the components corresponding to the cutting insert 10 and the cutter body 50, which have the same function or configuration, will be omitted or simplified, and different components will be mainly described.

7 and 8 correspond to FIGS. 1 and 2. That is, FIGS. 7A, 7B, and 7C are a perspective view, a front view, and a right side view of the cutting insert 70, respectively. Further, FIGS. 8A, 8B, 8C and 8D are a plan view, a bottom view, a left side view and a rear view of the cutting insert 70, respectively.

In these drawings, the first surface 74, the second surface 78, the third surface 76, the fourth surface 80, the fifth surface 72, and the sixth surface 82 are the first surface 14 and the second surface 18 of the cutting insert 10, respectively. , Third surface 16, fourth surface 20, fifth surface 12, and sixth surface 22.

Then, the auxiliary cutting edge 84B is formed at the connecting portion between the first surface 74 including the surface functioning as the rake surface and the fifth surface 72 functioning as the flank, and the connection between the first surface 74 and the third surface 76. A main cutting edge 84A is formed in the portion, and a corner cutting edge 84C is formed so as to connect the both.

In both FIGS. 7(b) and 8(d), the first surface 74 and the second surface 78 of the cutting insert 70 are as shown by the line segments of the first surface 74 and the second surface 78. It is formed from parallel planes and is attached to the cutter body 50 parallel to the rotation axis AX.

Comparing the cutting insert 10 and the cutting insert 70, for example, as shown in FIGS. 1(b) and 7(b) showing a tip end view seen from the tip end side of the rotation axis AX, both approach the rotation axis AX. It is common that the second surface 18 (or the second surface 78) is inclined with respect to the first surface 14 (or the first surface 74) so that the thicknesses of the cutting insert 10 and the cutting insert 70 become larger. It is also common that the fourth surface 20 (or the fourth surface 80) is closer to the rotation axis AX as it goes toward the base end side of the rotation axis AX.

On the other hand, in the cutting insert 70, the first surface 74 and the second surface 78 are provided in parallel, so that the distance between the two is constant regardless of the position in the rotation axis AX direction.

Further, as shown in FIG. 7B, in the front end view, in the cutting insert 70, the first surface 74 is substantially parallel to the line connecting the rotation axis AX and the main cutting edge 84A. The second surface 78 is different from the cutting insert 10 in that it is inclined.

Even with such a cutting insert 70, it is possible to apply a force pressing the cutting body 70 toward the cutter body 50 in both the rotational direction and the radial direction. Further, by pressing a member having a conical surface such as the male screw 60 against the fourth surface 80, it becomes possible to simultaneously support and fix the one or more cutting inserts 70 to the body such as the cutter body 50. ..

[Modification 3]
9 and 10 correspond to FIGS. 1 and 2. That is, FIGS. 9A, 9B, and 9C are a perspective view, a front view, and a right side view of the cutting insert 90, respectively. Further, FIGS. 10A, 10B, 10C, and 10D are a plan view, a bottom view, a left side view, and a rear view of the cutting insert 90, respectively.

In these drawings, the first surface 94, the second surface 98, the third surface 96, the fourth surface 100, the fifth surface 92, and the sixth surface 102 are the first surface, the second surface 18, and the second surface 18, respectively, of the cutting insert 10. It corresponds to the third surface 16, the fourth surface 20, the fifth surface 12, and the sixth surface 22.

Then, the auxiliary cutting edge 104B is formed at the connecting portion between the first surface 94 including the surface functioning as the rake surface and the fifth surface 92 functioning as the flank, and the connection between the first surface 94 and the third surface 96. A main cutting edge 104A is formed in the portion, and a corner cutting edge 104C is formed so as to connect the both.

In both FIGS. 9(b) and 9(d), the first surface 94 and the second surface 98 of the cutting insert 90 are as shown by the line segments of the first surface 94 and the second surface 98. It is formed from parallel planes and is attached to the cutter body 50 parallel to the rotation axis AX.

Comparing the cutting insert 10 and the cutting insert 90, for example, as shown in FIGS. 1(b) and 9(b) showing a tip end view seen from the tip end side of the rotation axis AX, both approach the rotation axis AX. It is common that the second surface 18 (or 98) is inclined with respect to the first surface 14 (or 94) so that the thicknesses of the cutting insert 10 and the cutting insert 90 become larger. It is also common that the fourth surface 20 (or the fourth surface 100) is closer to the rotation axis AX as it goes toward the base end side of the rotation axis AX.

On the other hand, in the cutting insert 90, since the first surface 94 and the second surface 98 are provided in parallel, the distance between the two is constant regardless of the position in the rotation axis AX direction. Further, as shown in FIG. 9B, the cutting insert 90 is not parallel to the first surface 94 and the second surface 98 as compared with the line connecting the rotation axis AX and the main cutting edge 104A in the front end view. Is different from the cutting insert 10 in that it is formed.

Even such a cutting insert 90 can be fixed to the body not only in the rotational direction but also in the radial direction. Further, by pressing a member having a conical surface such as the male screw 60 against the fourth surface 100, it becomes possible to simultaneously support and fix one or a plurality of cutting inserts 90 to a body such as the cutter body 50. ..

The distance between the first surface 94 and the second surface 98 may be constant when viewed from the direction perpendicular to the rotation axis AX.

10, 70, 90... Cutting insert, 12, 72, 92... Fifth surface, 14, 74, 94... First surface, 16, 76, 96... Third surface, 18, 78, 98... Second surface, 20 , 80, 100... Fourth surface, 22, 82, 102... Sixth surface, 24A, 84A, 104A... Main cutting edge, 24B, 84B, 104B... Sub cutting edge, 24C, 84C, 104C... Corner edge, 50... Cutter body, 52... Holder part, 60... Male screw, 62... Screw part, 64... Head part, 66... Neck part, 68... Wedge, AX... Rotating shaft, AX2... Shaft

Claims (8)

A cutting insert attached to a body that rotates about a rotation axis,
A first surface having a first clamp surface facing the direction of rotation and abutting the body;
A second surface having a second clamp surface facing the opposite direction to the first surface and abutting the body;
A third surface facing radially outward of the rotary shaft;
A fourth surface facing inward in the radial direction of the rotating shaft;
A fifth surface which is in the direction of the rotation axis and faces the body tip side;
A sixth surface which is in the rotation axis direction and faces the body proximal end side;
A cutting edge provided at least in a connecting portion that connects the first surface and the third surface,
A cutting insert comprising
In a cross section perpendicular to the rotation axis, the second clamp surface is inclined with respect to the first clamp surface such that the distance between the first clamp surface and the second clamp surface increases as the distance from the cutting edge increases. And
The fourth surface includes an inclined surface whose distance from the rotation axis becomes smaller as it goes toward the body proximal end side .
In a cross section that is parallel to the rotation axis and passes through the first clamp surface and the second clamp surface, the distance between the first clamp surface and the second clamp surface may change according to the position on the rotation axis. The cutting insert in which the second clamp surface is inclined with respect to the first clamp surface . In a cross section that is parallel to the rotation axis and passes through the first clamp surface and the second clamp surface, the distance between the first clamp surface and the second clamp surface becomes larger as it advances toward the body proximal end side. The cutting insert according to claim 1, wherein: The cutting insert according to claim 1 or 2 , wherein the first clamping surface is parallel to the rotation axis. The cutting insert according to claim 1 or 2 , wherein the first clamping surface is inclined with respect to the rotation axis so that the first clamping surface advances in the direction of rotation as it advances toward the tip end side of the body. The cutting insert according to claim 1 or 2 , wherein the first clamping surface is inclined with respect to the rotation axis so that the first clamping surface advances in the direction of rotation as it advances toward the body proximal end side. A cutting insert attached to a body that rotates about a rotation axis,
A first surface having a first clamp surface facing the direction of rotation and abutting the body;
A second surface having a second clamp surface facing the opposite direction to the first surface and abutting the body;
A third surface facing radially outward of the rotary shaft;
A fourth surface facing inward in the radial direction of the rotating shaft;
A fifth surface which faces the tip end side of the body in the rotation axis direction,
A sixth surface which is in the rotation axis direction and faces the body proximal end side;
A cutting edge provided at least in a connecting portion that connects the first surface and the third surface,
A cutting insert comprising
In a cross section perpendicular to the rotation axis, the second clamp surface is inclined with respect to the first clamp surface such that the distance between the first clamp surface and the second clamp surface increases as the distance from the cutting edge increases. Then
The fourth surface is provided with an inclined surface that is inclined with respect to the rotation axis such that the distance to the rotation axis becomes smaller toward the base end side of the body and that is also inclined with respect to the third surface. ,
Cutting inserts. In a cross section that is parallel to the rotation axis and passes through the first clamp surface and the second clamp surface, the distance between the first clamp surface and the second clamp surface may change according to the position on the rotation axis. In addition, the second clamp surface is inclined with respect to the first clamp surface.
The cutting insert according to claim 6. In a cross section that is parallel to the rotation axis and passes through the first clamp surface and the second clamp surface, the distance between the first clamp surface and the second clamp surface becomes larger as it advances toward the body proximal end side. The cutting insert according to claim 6 or 7.