JP5678431B2 - Exchangeable grooving tool and peripheral grooving method - Google Patents

Description

  The present invention relates to a blade-exchange-type grooving tool and a circumferential grooving method using the same.

  Conventionally, a work piece made of a metal material or the like is rotated around a rotation axis, and a groove is formed by a cutting insert cutting edge on the outer peripheral surface of the work material or an inner peripheral surface of a machining hole formed around the rotation axis. 2. Description of the Related Art There is known a blade edge exchange type grooving tool for performing a machining process. For example, in a conventional cutting edge-replaceable grooving tool 100 shown in FIG. 25, a cutting insert 30 formed in a rod shape having a rectangular cross section is detachably attached to the tip of a tool body 1 having an axial shape. The cutting insert 30 has a pair of cutting edges 32 at both ends in the extending direction (vertical direction in FIG. 25) of the rod-shaped insert main body 31. Of these cutting edges 32, one cutting edge 32 </ b> A protruding from the tip surface of the tool body 1 is perpendicular to the rotation axis WO so as to be along the stepped portion U of the work material W formed in a multistage cylindrical shape. By moving in the Y direction, the outer peripheral surface R of the work material W is subjected to grooving (outer diameter grooving). In the example of FIG. 25, the stepped portion U of the work material W is formed with an end face E adjacent to the small diameter portion of the outer peripheral surface R of the work material W and perpendicular to the rotation axis WO. The blade 32A is grooved into the small diameter portion by moving along the end face E. The cutting insert 30 is rotationally symmetric with respect to an insert height axis C3 that passes through the center in the extending direction and the width direction of the insert body 31 and extends in the height direction perpendicular to the extending direction and the width direction. It is formed symmetrically with respect to an insert virtual plane (not shown) that includes the height axis C3 and is orthogonal to the extending direction, regardless of whether the specification of the tool body 1 is left-handed or right-handed. 32B can be used.

  In FIG. 25, the other cutting edge 32B of the pair of cutting edges 32 is not used for cutting, and when one of the cutting edges 32A becomes unsuitable for use due to wear, chipping, or the like, Is inverted in the extending direction so that the cutting edge 32B protrudes from the tip surface of the tool body 1 and is used for grooving.

  In the example of FIG. 26, the above-mentioned cutting insert 30 is detachably attached to the tip of an axially replaceable cutting edge grooving tool 105. In this example, the cutting insert 30 extends in the vertical direction (Y direction) in FIG. 26, and one cutting edge 32 </ b> A protrudes from the outer peripheral surface of the tip portion of the tool body 1. Then, this one cutting edge 32A performs grooving processing (inner diameter grooving) on the inner peripheral surface S of the processing hole H of the work material W. A back surface (end surface) B that is adjacent to the inner peripheral surface S and orthogonal to the rotation axis WO is formed in the processing hole H of the work material W, and one of the cutting edges 32A extends along the end surface B. The inner circumferential surface S is grooved by moving in the Y direction perpendicular to the rotation axis WO.

In this manner, circumferential grooving such as outer grooving and inner grooving using the blade-replaceable grooving tools 100 and 105 is performed.
Moreover, what was described in patent document 1 is known as another cutting insert used for such a grooving process, for example.

Japanese Patent Publication No.7-115251

However, the above-mentioned blade edge replaceable grooving tools 100 and 105 have the following problems.
The cutting insert 30 is arranged such that the extending direction of the insert main body 31 (the insert longitudinal axis C1 shown in FIGS. 25 and 26) extends in parallel to the end faces E and B of the work material W. The cutting edges 32 have the same distance from the end faces E and B. There is no particular problem when one cutting edge 32A is separated from the end faces E and B of the work material W and grooved into the peripheral surface in such an arrangement state of the cutting insert 30; When grooving the peripheral surface while moving along the end faces E and B of the work material W, the other cutting edge 32B comes into contact with the end faces E and B and is damaged. In the outer diameter grooving of FIG. 25, the relationship between the diameter φd1 of the large diameter portion where the end face E is formed in the work material W and the distance L3 from the other cutting edge 32B to the rotation axis WO is d1 / 2. <L3, there is no contact, but since contact is made when d1 / 2 ≧ L3, the shape of the work material W is limited, and the distance L3 is reduced during processing, and the contact described above. May occur. When such contact occurs, not only the processing accuracy of the work material W cannot be ensured, but also the other unused cutting edge 32B is damaged. Specifically, as shown in FIG. 27, the corner portion 43 </ b> C located on the end surface E, B side of the work material W at the other cutting edge 32 </ b> B contacts the end surfaces E, B. For this reason, the peripheral surface grooving along the end surfaces E and B of the work material W as shown in FIGS. 25 and 26 could not be performed.

  In order to prevent such contact of the cutting edge 32B with the end faces E and B, for example, it is conceivable to change the posture of the cutting insert 30 attached to the tool body 1. That is, as shown in FIGS. 28 and 29, when viewed from the rake face 33 side (the upper surface side of the insert main body 31) of the cutting insert 30, the insert longitudinal axis C1 of the insert main body 31 is from one cutting edge 32A side to the other. The cutting insert 30 may be attached to the tool body 1 while being inclined with respect to the Y direction so as to gradually move away from the end face E (B) of the workpiece W as it goes toward the cutting edge 32B. Thereby, since the corner part 43C arrange | positioned in the cutting insert 30 at the end surface E (B) side of the other cutting edge 32B is spaced apart from this end surface E (B), the above-mentioned contact is prevented. The

  However, in this case, if attention is paid to one of the cutting edges 32A, as shown in FIG. 29, the front cutting edge 41 of the cutting edge 32A has an angle α in the drawing with respect to a virtual line WO1 parallel to the rotation axis WO. Will be inclined. Originally, the groove bottom D of the groove formed by grooving is required to be parallel to the rotation axis WO. However, as described above, the front cutting edge 41 is inclined, so that the cut groove The groove bottom D is also inclined by the angle α with respect to the rotation axis WO, and sufficient processing accuracy cannot be ensured.

  On the other hand, in the cutting insert described in Patent Document 1, while the cutting insert is formed rotationally symmetrical with respect to the insert height axis, it is not formed plane-symmetrically with respect to the insert virtual plane, It is formed to be twisted as a whole. When the cutting insert is mounted on the tool body, the corner portion on the end surface E (B) side of the other cutting edge is more end-face E (B than the corner portion on the end surface E (B) side of the one cutting edge. ). However, in this case, left-handed and right-handed cutting inserts must be prepared in accordance with the specifications of the tool body, which increases the number of parts and makes management complicated.

  The present invention has been made in view of such circumstances, and even when the peripheral surface grooving is performed along the end surface of the work material without increasing the number of parts of the cutting insert, the processing accuracy is increased. It is an object of the present invention to provide a blade replacement type grooving tool and a peripheral surface grooving method capable of sufficiently ensuring the above.

In order to achieve the above object, the present invention proposes the following means.
That is, the present invention relates to a cutting insert in which a cutting edge protrudes toward the peripheral surface of a work material that rotates about a rotation axis, and a tool that has an axial shape and is detachably attached to a tip portion. A cutting edge replacement type grooving tool that grooving the peripheral surface with the cutting blade, wherein the cutting insert is at both ends in the extending direction of the rod-shaped insert body. A pair of cutting edges on the upper surface of the insert body, and a rotational symmetry with respect to the insert height axis passing through the center in the extending direction of the insert body and the center in the width direction orthogonal to the extending direction. And an insert imaginary plane that is perpendicular to the extending direction and includes the insert height axis, and the cutting edge is formed at the edge of the insert body in the extending direction. A front cutting edge extending along the width direction, a pair of corner portions disposed at both ends of the front cutting edge and projecting in the width direction, and a center of the insert body along the extending direction from the corner portion A pair of side cutting edges extending so as to gradually narrow each other as it goes to the side, and the tool body projects one of the pair of cutting edges in the grooving direction. The cutting insert is mounted, and the cutting insert is disposed on the tool body so as to be along one side surface facing the side of the tool body, and the grooving direction is the tip of the tool body. The cutting insert has an insert width axis along the width direction passing through the center in the extending direction of the insert main body, and the pair of corner portions in the width direction. And gradually inclines toward the upper side of the tool body as it goes in the width direction of the other, which is the direction from one corner portion located in a direction away from the center axis of the tool body to the other corner portion, The insert longitudinal axis passing through the center in the width direction of the insert body and extending along the extending direction is inclined with respect to a virtual tool plane that includes one corner portion of the one cutting edge and is perpendicular to the vertical direction of the tool body. And, in the extending direction, the tool gradually approaches the imaginary plane as it goes from the other cutting edge of the pair of cutting edges toward the one cutting edge. One corner portion that extends toward the upper side of the tool body and is located on the side opposite to the other width direction of the other cutting edge is formed on the one cutting edge. The one of the two corners is disposed on the other width direction side of the one corner portion, and the one of the other cutting edges is positioned away from the central axis of the tool body than the other corner portion. A corner portion is arranged in a direction approaching the central axis with respect to the one corner portion positioned in a direction away from the central axis than the other corner of the one cutting edge. And
The present invention also provides a cutting insert having a cutting edge projecting toward the peripheral surface of a work material that rotates about a rotation axis, and a tool that has a shaft shape and is detachably attached to the tip portion. A cutting edge replacement type grooving tool that grooving the peripheral surface with the cutting blade, wherein the cutting insert is at both ends in the extending direction of the rod-shaped insert body. A pair of cutting edges on the upper surface of the insert body, and a rotational symmetry with respect to the insert height axis passing through the center in the extending direction of the insert body and the center in the width direction orthogonal to the extending direction. And an insert imaginary plane that includes the insert height axis and is perpendicular to the extending direction, and the cutting edge is formed at the edge of the insert body in the extending direction and has the width. A front cutting edge extending along the direction, a pair of corner portions disposed at both ends of the front cutting edge and projecting in the width direction, and a center side of the insert body along the extending direction from the corner portion A pair of side surface cutting edges each extending so as to gradually narrow each other as it goes to the tool body, and the tool body projects one of the pair of cutting edges in the grooving direction, The cutting insert is mounted, and the cutting insert is arranged on the tool body so as to be along a tip surface facing the tip side of the tool body, and the grooving direction is a central axis of the tool body. The cutting insert has an insert width axis that extends through the center of the extending direction of the insert body and extends along the width direction, and the pair of corners out of the width direction. And gradually tilting upward toward the upper side of the tool body as it goes in the other width direction from one corner portion located on the tip side of the tool body to the other corner portion, and the width of the insert body The insert longitudinal axis passing through the center of the direction and extending along the extending direction is inclined with respect to a tool virtual plane that includes one corner portion of the one cutting edge and is perpendicular to the vertical direction of the tool body, and Of the extending direction, the upper side of the tool body gradually approaches the tool imaginary plane as it goes to one extending direction that is a direction from the other cutting edge to the one cutting edge of the pair of cutting edges. One corner portion of the other cutting edge located on the opposite side of the other width direction is the one of the one cutting edge. The one corner portion located on the tip side of the tool body with respect to the other corner portion of the other cutting edge is disposed on the other width direction side of the other corner portion of the other cutting edge. It is characterized by being arranged on the base end side of the tool main body with respect to the one corner portion located on the distal end side of the tool main body with respect to the other corner portion of the cutting edge.
The present invention also provides a cutting insert having a cutting edge projecting toward the peripheral surface of a work material that rotates about a rotation axis, and a tool that has a shaft shape and is detachably attached to the tip portion. A peripheral grooving method for grooving the peripheral surface of the work material with the cutting edge using a blade-exchangeable grooving tool having a main body, wherein the cutting insert is a rod-shaped insert A pair of cutting edges are provided on the upper surface of the insert main body at both ends in the extending direction of the main body, passing through the center in the extending direction of the insert main body and the center in the width direction orthogonal to the extending direction, and It is formed rotationally symmetric with respect to the insert height axis perpendicular to the width direction and symmetric with respect to the insert virtual plane that includes the insert height axis and is perpendicular to the extending direction. A front cutting edge that is formed at an edge in the extending direction of the front edge and extends along the width direction, a pair of corner portions that are arranged at both ends of the front cutting edge and project in the width direction, and the corner portion. A pair of side cutting edges extending so as to gradually narrow each other as it goes toward the center side of the insert body along the extending direction, and the cutting insert is one of the pair of cutting edges. When projecting the cutting edge in the grooving direction and mounting it on the tool body, and grooving the peripheral surface by moving the one cutting edge along the grooving direction, The insert width axis along the width direction passing through the center in the extending direction of the insert body is changed from one corner portion to the other corner portion in the pair of corner portions in the width direction. Is inclined toward the opposite side to the gradual rotation direction of rotation of the workpiece as it goes to the other width direction in Cow, the insert longitudinal axis along the center in the width direction of the insert body as the extending direction The one cutting edge is inclined with respect to a virtual virtual plane including one corner portion and the rotation axis of the one cutting edge, and the one cutting edge from the other cutting edge of the pair of cutting edges in the extending direction. The direction of the workpiece is extended toward the opposite side of the rotation direction so as to gradually approach the tool imaginary plane as it goes toward one of the extending directions, and the peripheral surface of the work material extends to the rotation axis. It is an outer peripheral surface facing the outer side in the orthogonal radial direction, and is opposed to an end surface of the work material that rises toward the outer side in the radial direction adjacent to the outer peripheral surface and is perpendicular to the rotation axis. Then, the one corner portion of the other cutting edge is disposed away from the one corner portion cut into the outer peripheral surface along the end face of the one cutting edge.
The present invention also provides a cutting insert having a cutting edge projecting toward the peripheral surface of a work material that rotates about a rotation axis, and a tool that has a shaft shape and is detachably attached to the tip portion. A peripheral grooving method for grooving the peripheral surface of the work material with the cutting edge using a blade-exchangeable grooving tool having a main body, wherein the cutting insert is a rod-shaped insert A pair of cutting edges are provided on the upper surface of the insert main body at both ends in the extending direction of the main body, passing through the center in the extending direction of the insert main body and the center in the width direction orthogonal to the extending direction, and It is formed rotationally symmetric with respect to the insert height axis perpendicular to the width direction and symmetric with respect to the insert virtual plane that includes the insert height axis and is perpendicular to the extending direction. A front cutting edge that is formed at an edge in the extending direction of the front edge and extends along the width direction, a pair of corner portions that are arranged at both ends of the front cutting edge and project in the width direction, and the corner portion. A pair of side cutting edges extending so as to gradually narrow each other as it goes toward the center side of the insert body along the extending direction, and the cutting insert is one of the pair of cutting edges. When projecting the cutting edge in the grooving direction and mounting it on the tool body, and grooving the peripheral surface by moving the one cutting edge along the grooving direction, The insert width axis along the width direction passing through the center in the extending direction of the insert body is changed from one corner portion to the other corner portion in the pair of corner portions in the width direction. Is inclined toward the opposite side to the gradual rotation direction of rotation of the workpiece as it goes to the other width direction in Cow, the insert longitudinal axis along the center in the width direction of the insert body as the extending direction The one cutting edge is inclined with respect to a virtual virtual plane including one corner portion and the rotation axis of the one cutting edge, and the one cutting edge from the other cutting edge of the pair of cutting edges in the extending direction. The direction of the workpiece is extended toward the opposite side of the rotation direction so as to gradually approach the tool imaginary plane as it goes toward one of the extending directions, and the peripheral surface of the work material extends to the rotation axis. It is an inner peripheral surface facing the inner side of the orthogonal radial direction, and among the work material, an end surface that rises inward in the radial direction adjacent to the inner peripheral surface and is formed perpendicular to the rotation axis versus Then, the one corner portion of the other cutting edge is disposed away from the one corner portion cut into the inner peripheral surface along the end surface of the one cutting edge. .

  According to the cutting edge replaceable grooving tool and the peripheral grooving method according to the present invention, the front cutting edge in one cutting edge of the cutting insert protruding from the tip of the tool body toward the peripheral surface of the work material Is inclined toward the rear side of the rotational direction in which the workpiece gradually rotates as it goes in the other width direction so as to be parallel to the insert width axis. On the other hand, a negative angle is set. Therefore, one of the cutting edges can stably cut the work material with high accuracy.

  Further, the insert longitudinal axis of the cutting insert is inclined so as to gradually approach the virtual tool plane as it goes in the one extending direction, and extends toward the upper surface side of the insert body. That is, since the other cutting edge is separated toward the lower surface side of the insert body with respect to the tool virtual plane, one cutting edge cuts sharply with respect to the peripheral surface of the work material, and the sharpness is reduced. Can be increased sufficiently.

  In addition, one corner portion located on the opposite side to the other width direction in the other cutting edge is opposite to the one corner portion located on the opposite side in the one cutting edge in the other width direction side. Is arranged. Thereby, for example, when performing grooving (outer diameter grooving) on the outer peripheral surface of the work material along the end surface orthogonal to the rotation axis in the step portion of the work material having a multistage cylindrical shape, There are the following effects. That is, for example, one corner portion of one cutting edge of the cutting insert is disposed close to the end surface of the work material, and this cutting insert is moved along the end surface in the grooving direction to perform grooving. When this is done, it is reliably prevented that one corner portion of the other cutting edge is separated from the end surface and the corner portion contacts the end surface and is damaged. Further, the contact prevents the other unused cutting edge from being damaged. In this case, regardless of the diameter d1 of the large-diameter portion of the work material W described in FIG. 25, one corner portion of the other cutting edge is separated from this end surface, and this corner portion contacts the end surface. Can be surely prevented from being damaged. Also, when grooving (inner diameter grooving) to the inner peripheral surface of the processing hole along the inner surface (end surface) of the cylindrical hole-shaped processing hole formed around the rotation axis of the work material, The same effects as described above are achieved.

  Further, when attention is paid to the groove bottom of the work material to be cut by one of the cutting edges, the insert width axis of the cutting insert is gradually inclined toward the rear side in the rotational direction in which the work material rotates as it goes to the other width direction. And the insert longitudinal axis is inclined toward the upper surface side of the insert body so as to approach the tool virtual plane as it goes in the one extending direction, and one corner portion of the other cutting edge The groove bottom is formed with an inclination close to parallel to the rotation axis of the work material by being disposed on the other width direction side of the one corner portion of the cutting edge. That is, the angle α of the groove bottom D described with reference to FIG. 29 is formed to be relatively small, and the machining accuracy of the groove cut into the work material is increased.

  In addition, since the pair of side surface cutting blades provided in each cutting edge are formed to be inclined so as to gradually narrow each other from the outside in the extending direction of the insert body toward the center side, the processing of the groove wall Accuracy is ensured. In other words, even if the mounting posture of the cutting insert with respect to the tool body is set as described above, the side cut disposed on the side opposite to the end face side of the work material (that is, the other width direction side) on one cutting edge. The blade does not come into contact with the opening edge of the groove wall on the opposite side of the groove formed in the work material.

Moreover, in the cutting edge exchange-type grooving tool according to the present invention, when the cutting insert is viewed from a direction orthogonal to the tool virtual plane, an angle θ1 formed by the insert width axis and the rotation axis is 0 ° ≦ θ1 ≦. It may be set to 0.5 °.
In the circumferential grooving method according to the present invention, when the cutting insert is viewed from a direction orthogonal to the tool virtual plane, an angle θ1 formed by the insert width axis and the rotation axis is 0 ° ≦ θ1 ≦. It is good also as setting to 0.5 degree.

According to the cutting edge replaceable grooving tool and the peripheral surface grooving method according to the present invention, for example, when the end surface of the work material is formed perpendicular to the rotation axis, the extending direction of the insert body is covered. The angle inclined with respect to the end face of the cutting material is set to a value slightly larger than θ1 while approximating the set value of the angle θ1 formed by the insert width axis and the rotation axis. That is, the orientation of the cutting insert with respect to the tool body is substantially parallel with the extending direction (insert longitudinal axis) of the insert body being substantially inclined with respect to the end surface of the work material, as described above. One corner of the other cutting edge can be reliably separated from the end face. Therefore, the processing accuracy of the groove bottom of the grooved work material is more reliably increased.

  Further, in the cutting edge-replaceable grooving tool according to the present invention, the peripheral surface is an outer peripheral surface facing away from the rotation axis of the work material, and the one cutting edge is in relation to the outer peripheral surface. It is good also as carrying out an outer diameter grooving process.

  According to the cutting edge exchange type grooving tool according to the present invention, for example, in the step portion of the work material having a multi-stage columnar shape, an end surface that is formed of an annular surface adjacent to the small diameter portion of the outer peripheral surface and orthogonal to the rotation axis is formed Even if it is the case, it is possible to perform grooving with high accuracy regardless of the position of the outer peripheral surface to be grooved.

Further, in the cutting edge exchange-type grooving tool according to the present invention, the tool body has the cutting insert arranged along one side surface facing the side of the tool body, and the one cutting edge is the The cutting insert projects from the distal end surface toward the distal end side, and the cutting insert has the front cutting edge of the one cutting edge facing the side opposite to the one side surface from the one side surface side. The negative angle may be set by gradually inclining toward the upper side of the tool body as it goes toward the other side surface.

  According to the cutting edge exchange type grooving tool according to the present invention, the front cutting edge of one of the cutting edges is set to the negative angle as described above, so that cutting can be performed stably with high accuracy. Specifically, when the cutting edge-replaceable grooving tool is mounted on a machine tool or the like, the other side surface of the tool body is brought into contact with the machine tool or the like. Since the front cutting edge of one cutting edge of the cutting insert is set to the negative angle as described above, the component force of the cutting resistance received by one cutting edge during the cutting process is applied to the other side of the tool body. It acts to press against the machine. This stabilizes the position of the cutting edge exchange-type grooving tool with respect to the machine tool or the like at the time of cutting, and allows highly accurate cutting to be performed stably.

  Further, in the edge-changing grooving tool according to the present invention, the peripheral surface is an inner peripheral surface facing the rotation axis side of the work material, and the one cutting edge has an inner diameter with respect to the inner peripheral surface. Grooving may be performed.

  According to the cutting edge replaceable grooving tool according to the present invention, for example, a back surface (end surface) perpendicular to the rotation axis is formed adjacent to the inner peripheral surface of a cylindrical hole-shaped processing hole formed in a work material. Even in the case where the groove is formed, it is possible to perform grooving with high accuracy regardless of the position of the inner peripheral surface to be grooved.

Moreover, in the cutting edge-replaceable grooving tool according to the present invention, the tool body projects the one cutting edge from the outer peripheral surface of the tip end sideward, and the cutting insert is the one of the cutting inserts. The front cutting edge of the cutting edge may be gradually inclined toward the upper side of the tool body as it goes from the distal end side to the proximal end side of the tool body, and may be set to a negative angle.

According to the cutting edge exchange type grooving tool according to the present invention, the front cutting edge of one of the cutting edges is set to the negative angle as described above, so that cutting can be performed stably with high accuracy. Specifically, when the cutting edge exchange type grooving tool is mounted on a machine tool or the like, the base end side portion of the tool body is brought into contact with the machine tool or the like. Since the front cutting edge of one cutting edge of the cutting insert is set to the negative angle as described above, the component force of the cutting resistance received by one cutting edge during cutting processing is the base end side portion of the tool body. Acts to press against the machine tool or the like. This stabilizes the position of the cutting edge exchange-type grooving tool with respect to the machine tool or the like at the time of cutting, and allows highly accurate cutting to be performed stably.
Further, in the circumferential grooving method according to the present invention, the front cutting edge of the one cutting edge is gradually inclined toward the opposite side to the rotation direction as it is separated from the end face, so that a negative angle is obtained. It may be set.
Moreover, in the blade edge exchange-type grooving tool according to the present invention, the distances from the pair of corner portions to the rotation axis in the one cutting edge may be set to be the same.
In the circumferential grooving method according to the present invention, the distances from the pair of corner portions to the rotation axis in the one cutting edge may be set to be the same.
According to the cutting edge-replaceable grooving tool and the circumferential grooving method according to the present invention, the distances from the pair of corner portions to the rotation axis of the work material are set to be the same as each other. The groove bottom of the work material to be cut with one of the cutting edges can be formed parallel to the rotation axis. Therefore, the finishing accuracy of the groove of the work material is sufficiently ensured.

Further, in the edge-changing grooving tool according to the present invention, the corner portion has a convex-curved first corner blade, and the one corner portion of the one cutting edge is adjacent to the corner portion. An intersection of the extension line of the front cutting edge and the perpendicular line extending from the outer edge portion in the width direction of the first corner edge toward the extension line may be disposed on the tool virtual plane.
Moreover, in the peripheral grooving method according to the present invention, the corner portion has a convex-curved first corner blade, and the one corner portion of the one cutting edge is adjacent to the corner portion. An intersection of the extension line of the front cutting edge and the perpendicular line extending from the outer edge portion in the width direction of the first corner edge toward the extension line may be disposed on the tool virtual plane.

According to the cutting edge replaceable grooving tool and the peripheral surface grooving method according to the present invention, the corner portion of the cutting edge has the first corner blade having a convex curve shape, so that the cutting edge chipping at the corner portion, etc. Is prevented.

Further, in the cutting edge replaceable grooving tool according to the present invention, the corner portion is a linear first connecting the end portion on the center side in the extending direction of the insert body in the first corner blade and the side face cutting blade. The second corner blade may extend so as to be orthogonal to the rotational axis of the work material when the cutting insert is viewed from a direction orthogonal to the tool virtual plane. Good.
Further, in the circumferential grooving method according to the present invention, the corner portion is a linear first connecting the end portion on the center side in the extending direction of the insert body in the first corner blade and the side surface cutting blade. It has two corner blades, and when the cutting insert is viewed from the direction orthogonal to the tool virtual plane, the second corner blade is extended and arranged so as to be orthogonal to the rotation axis of the work material. Also good.

According to the cutting edge-replaceable grooving tool and the circumferential grooving method according to the present invention, the corner portion of the cutting edge includes a central end portion along the extending direction of the insert body in the first corner blade and a side cut. Since the second corner blade connecting the blade extends so as to be orthogonal to the rotation axis of the work material, the groove wall of the work material cut by the front face cutting edge of the one cutting edge and the first corner blade This second corner blade is exposed, and the finishing accuracy of the groove wall is improved.

  According to the cutting edge replaceable grooving tool and the circumferential grooving method according to the present invention, the circumferential grooving is performed along the end surface of the work material without increasing the number of parts of the cutting insert. Can also ensure sufficient machining accuracy.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic perspective view showing a cutting edge replaceable grooving tool according to a first embodiment of the present invention and a work material to be subjected to grooving using this cutting edge replaceable grooving tool. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic perspective view showing a cutting edge replaceable grooving tool according to a first embodiment of the present invention and a work material to be subjected to grooving using this cutting edge replaceable grooving tool. It is the top view which looked at the cutting edge exchange type grooving tool and work material which concern on the 1st Embodiment of this invention from the direction which opposes the rake face of a cutting insert, and is the figure which looked at the cutting insert from the upper surface. is there. It is a schematic side view which shows the blade-tip-exchange-type grooving tool and work material which concern on the 1st Embodiment of this invention. It is a figure which expands and shows the cutting insert 30 vicinity in FIG. It is the front view which looked at the blade-tip-exchange-type grooving tool and work material which concern on the 1st Embodiment of this invention from the front end side of the tool main body. It is a side view which shows the blade-tip-exchange-type grooving tool which concerns on the 1st Embodiment of this invention. It is the front view which looked at the blade-tip-exchange-type grooving tool which concerns on the 1st Embodiment of this invention from the front end side of the tool main body. It is a perspective view which shows the cutting insert. It is a figure which expands and shows one cutting edge 32A of the cutting insert 30 in FIG. It is a figure which expands and shows one cutting edge 32A of the cutting insert 30 in FIG. It is a figure which expands and shows the cutting insert 30 and the groove bottom D in FIG. It is a figure which expands and shows one cutting edge 32A and the end surface E of the cutting insert 30 in FIG. It is a figure explaining the mounting | wearing attitude | position of the cutting insert 30, and each distance from a pair of corner part 43 in one cutting blade 32A to rotation axis WO. FIG. 15 is a view of the cutting insert 30 in FIG. 14 as viewed from the side surface of the insert body 31 and a view as viewed from the top surface of the insert body 31. It is the figure which looked at the cutting insert 30 in FIG. 14 from the front of the insert main body 31. FIG. It is a schematic perspective view which shows the cutting edge exchange-type grooving tool which concerns on the 2nd Embodiment of this invention, and the workpiece which performs grooving using this cutting-edge exchange-type grooving tool. It is the top view which looked at the cutting-blade exchange type grooving tool and work material which concern on the 2nd Embodiment of this invention from the direction which opposes the rake face of a cutting insert, and is the figure which looked at the cutting insert from the upper surface. is there. It is the front view which looked at the blade-tip-exchange-type grooving tool and work material which concern on the 2nd Embodiment of this invention from the front end side of the tool main body, and is the figure which looked at the cutting insert from the side surface. It is a figure which expands and shows the cutting insert 30 and the groove bottom D in FIG. It is a figure explaining the mounting | wearing attitude | position of the cutting insert 30, and each distance from a pair of corner part 43 in one cutting blade 32A to rotation axis WO. It is the figure which looked at the cutting insert 30 in FIG. 21 from the side surface of the insert main body 31. FIG. It is a figure which shows the modification of the corner part in the cutting blade of a cutting insert. It is a figure which shows the modification of the corner part in the cutting blade of a cutting insert. It is the top view which looked at the conventional cutting edge exchange-type grooving tool (outer diameter grooving) and a work material from the direction which opposes the rake face of a cutting insert, and is the figure which looked at the cutting insert from the upper surface. It is the top view which looked at the conventional blade-tip-exchange-type grooving tool (inner diameter grooving) and a work material from the direction which opposes the rake face of a cutting insert, and is the figure which looked at the cutting insert from the upper surface. It is a figure which expands and shows the A section in FIG. 25, FIG. It is the top view which looked at the conventional cutting edge exchange type grooving tool and work material from the direction which opposes the rake face of a cutting insert, and is the figure which looked at the cutting insert from the upper surface. It is a figure which expands and shows the cutting insert 30 and the groove bottom D in FIG.

(First embodiment)
FIGS. 1-8 shows the cutting edge exchange-type grooving tool 10 which concerns on the 1st Embodiment of this invention, FIGS. 9-16 is the whole cutting insert 30 used for this cutting-edge-exchange-type grooving tool 10 FIG. Or a part is expanded and shown. The cutting edge-replaceable grooving tool 10 according to the present embodiment is detachably attached to a tool main body 1 that is formed in an axial shape and has a substantially rectangular cross section, and an end (front end) 3 on the front end side of the tool main body 1. A cutting insert 30 that is mounted and projects a cutting edge 32 from the front end surface 1A of the tool body 1 toward the front end side is provided.

  The cutting edge exchange-type grooving tool 10 of this embodiment performs an outer diameter grooving process on a substantially cylindrical work material W. Specifically, the work material W of the present embodiment has a multistage cylindrical shape, and has a stepped portion U between the large diameter portion and the small diameter portion. The stepped portion U of the work material W is formed with an end surface E that is formed of an annular surface that is adjacent to the outer peripheral surface R of the small-diameter portion and is orthogonal to the rotational axis WO. The cutting edge replaceable grooving tool 10 rotates about the rotation axis WO in a state where the extending direction (Y direction shown in the figure) of the tool body 1 is arranged substantially perpendicular to the rotation axis WO of the work material W. The tip 3 of the tool body 1 is directed to the step U on the outer peripheral surface R of the work material W rotating in the direction WT, the cutting edge 32 is moved along the end surface E of the step U, and the small diameter portion The outer peripheral surface R is cut. In the present embodiment, symbols X, Y, and Z indicating directions are used in some of the drawings. Here, symbols X and Y respectively indicate horizontal directions. Specifically, the X direction indicates the horizontal direction parallel to the rotation axis WO of the work material W, and the Y direction indicates the horizontal direction perpendicular to the rotation axis WO. Show. Moreover, the code | symbol Z has shown the perpendicular direction.

  The tool main body 1 is formed from a steel material or the like, and a central portion and a base end portion other than the tip end portion 3 form a substantially rectangular parallelepiped shape to form a shank portion 2. The cutting edge exchange type grooving tool 10 is fixedly supported by the machine tool M indicated by a two-dot chain line in FIG. 8 by being held in a state where the shank portion 2 is prevented from rotating. In the following description, in the Y direction, the distal end side (lower side in FIG. 3) of the tool body 1 may be referred to as one side, and the proximal end side (upper side in FIG. 3) may be referred to as the other side.

  The tip portion 3 of the tool body 1 has a substantially pentagonal shape in a plan view of FIG. 3, and an upper jaw portion 6 and a lower jaw portion 7 are formed so as to protrude from the tip face 1 </ b> A toward the tip side. The upper jaw portion 6 and the lower jaw portion 7 of the distal end portion 3 are opposed to each other in the vertical direction (Z direction), and one of the directions along the rotation axis WO (X direction in FIG. 3) on the distal end surface 1A. It is formed at the end of the side (left side in FIG. 3). As shown in FIGS. 4 and 5, the upper surface 3 </ b> A of the distal end portion 3 is formed to protrude upward from the upper surface of the shank portion 2. Further, the lower surface 3 </ b> B at the distal end portion 3 of the tool body 1 is flush with the lower surface 2 </ b> B of the shank portion 2.

  The tool body 1 has a side surface (one side surface) in which one side surface 3C facing the one side faces the one side in the shank portion 2 among both side surfaces facing the side (X direction in FIG. 3) at the tip portion 3. ) It is flush with 2C and forms side surfaces facing the one side of the upper jaw portion 6 and the lower jaw portion 7. Further, the distal end portion 3 is formed with another side surface 3D which is disposed to face the other side (the right side in FIG. 3) of the both side surfaces and to face the one side surface 3C. The other side surface 3D of the distal end portion 3 is flush with the side surface (other side surface) 2D whose base end portion faces the other side in the shank portion 2, and from the central portion toward the distal end portion, as it goes toward the distal end side. The taper is formed so as to be gradually inclined toward the one side. In addition, the shape of the front-end | tip part 3 of the tool main body 1 mentioned above is an example, and is not limited to this embodiment.

  As shown in FIG. 8, the cutting edge-replaceable grooving tool 10 includes the machine tool 1 in a state where at least the lower surface 2B and the other side surface 2D of the shank portion 2 of the tool body 1 are in contact with the mounting recess m of the machine tool M. Supported by M. Note that the lower surface 3B and the other side surface 3D of the tip 3 of the tool body 1 may not be supported by the mounting recess m.

  4 and 5, the upper jaw portion 6 of the distal end portion 3 has a substantially triangular shape, and the upper surface of the upper jaw portion 6 is gradually inclined toward the lower surface 3B side from the proximal end side toward the distal end side. Has been. Further, in this side view, the lower jaw portion 7 is formed in a substantially rectangular shape. The lower jaw portion 7 protrudes toward the distal end side of the tool body 1 from the upper jaw portion 6. A gap is provided between the upper jaw portion 6 and the lower jaw portion 7 to form an insert mounting seat 4 to which the cutting insert 30 is detachably mounted. The tool body 1 has a cutting insert 30 mounted on the insert mounting seat 4 and is disposed along the one side surface 3 </ b> C facing the side of the tool body 1.

  The insert mounting seat 4 has a substantially rectangular parallelepiped hole shape, and is located on the side surface 3C side of the tip 3 and extends in the Y direction. The insert mounting seat 4 has a distal end portion and a central portion located between the upper jaw portion 6 and the lower jaw portion 7 and opened on both sides in the X direction. Moreover, the front-end | tip part of the insert mounting seat 4 is opened also in the direction (groove insertion direction YA mentioned later) which faces the front end side among Y directions. Further, the base end portion of the insert mounting seat 4 is located between the upper surface 3A and the lower surface 3B and is open to the one side surface 3C. The insert mounting seat 4 is formed so as to be gradually inclined from the lower surface 3B to the upper surface 3A as it goes from the proximal end side to the distal end side of the tool body 1. In addition, a stepped portion 4 </ b> A facing the distal end side of the tool body 1 is formed at the base end portion of the insert mounting seat 4.

  Further, on the base end side of the insert mounting seat 4, a tightening portion 8 is formed which has a slit shape narrower than the insert mounting seat 4 and opens to the front end surface 1A, one side surface 3C and the other side surface 3D. . The tightening portion 8 is formed so as to be gradually inclined from the lower surface 3B toward the upper surface 3A as it goes from the proximal end side to the distal end side of the tool body 1.

  Further, the top wall surface 4B and the bottom wall surface 4C facing the top and bottom in the insert mounting seat 4 are each formed in a convex V shape when viewed from the front end surface 1A side, as shown in FIG. Further, as shown in FIG. 5, the tightening portion 8 is formed such that the space between the top wall surface 4 </ b> D and the bottom wall surface 4 </ b> E is narrow with respect to the insert mounting seat 4. A through-hole 5A is formed in the top wall surface 4D of the tightening portion 8 so as to open to the upper surface 3A of the distal end portion 3 and through which the clamp screw 5 is inserted. The bottom wall surface 4E of the tightening portion 8 is formed with a screw hole (not shown) that is coaxial with the through hole 5A and is subjected to female threading on the inner peripheral surface.

  Further, the cutting insert 30 to be mounted on the cutting edge-replaceable grooving tool 10 is made of a hard material such as cemented carbide, and as shown in FIG. 7, the extending direction of the rod-shaped insert body 31 (see FIG. 7). This is a so-called dog bone type cutting insert provided with a pair of cutting edges 32 on the upper surface (the surface facing upward in FIG. 7) of the insert main body 31 at both ends in the left and right direction.

  Here, reference sign C1 shown in FIGS. 9 to 16 and the like indicates an insert longitudinal axis along the extending direction of the insert body 31, and the insert longitudinal axis C1 is orthogonal to the extending direction in the insert body 31. While passing through the center in the width direction, the pair of cutting edges 32 extend through the center of front cutting edges 41 and 41, which will be described later. Further, symbol C2 indicates an insert width axis along the width direction of the insert body 31, and the insert width axis C2 is the center of the insert body 31 along the insert longitudinal axis C1 (part indicated by a double circle in the drawing). ), And extends in parallel to the front cutting edge 41 while being orthogonal to the insert longitudinal axis C1. Reference symbol C3 indicates an insert height axis along the height direction of the insert main body 31, and the insert height axis C3 passes through the center of the insert main body 31, and the insert longitudinal axis C1 and the insert width axis C2. Extend in directions orthogonal to each other.

  The cutting insert 30 is formed symmetrically (that is, plane-symmetric) with respect to the insert virtual plane VS1 that passes through the center of the insert body 31 along the insert longitudinal axis C1 and is perpendicular to the insert longitudinal axis C1. As shown in FIG. 13, the cutting insert 30 includes an insert longitudinal axis C1 and an insert height axis C3, and an upper surface of the insert body 31 (a surface facing upward in the vertical direction (Z direction) in FIG. 13) and The insert imaginary plane VS2 passing through the center of the lower surface (the surface facing downward in the Z direction in FIG. 13) is also symmetric (plane symmetric). That is, the cutting insert 30 is formed rotationally symmetric with respect to the insert height axis C3. The cutting insert 30 may not be formed symmetrically with respect to the insert virtual plane VS2.

  As shown in FIG. 13, the cutting insert 30 has a central portion in the extending direction on the upper surface of the insert main body 31 and a lower surface formed in a concave V shape in a cross section perpendicular to the insert longitudinal axis C <b> 1. ing. With such a shape of the insert main body 31, the cutting insert 30 is guided so as to be in sliding contact with the top wall surface 4B and the bottom wall surface 4C at the portion where the insert mounting seat 4 opens to the tip side, and from the one side to the other side. Inserted.

  As shown in FIG. 7, the cutting insert 30 inserted into the insert mounting seat 4 is positioned by abutting the other end face of the insert body 31 against the stepped portion 4 </ b> A. By tightening the clamp screw 5 in this state, the top wall surface 4D of the tightening portion 8 approaches while being elastically deformed toward the bottom wall surface 4E, and the top wall surface 4B of the insert mounting seat 4 is elastically deformed toward the bottom wall surface 4C. While approaching. Thus, the space | interval of top wall surface 4D, 4B and bottom wall surface 4E, 4C is narrowed, and the cutting insert 30 is fixedly supported by the front-end | tip part 3 of the tool main body 1. FIG.

  In addition, a pair of cutting edges 32 are disposed at both ends along the insert longitudinal axis C <b> 1 direction on the upper surface of the insert body 31. As shown in FIG. 12, the cutting edge 32 is a linear front cutting edge that is formed at the edge in the extending direction of the insert body 31 and extends in the width direction (left-right direction in FIG. 12) perpendicular to the extending direction. 41, a pair of corner portions 43 disposed at both ends of the front cutting edge 41 and projecting in the width direction, and the center side (inside) of the insert main body 31 along the extending direction from these corner portions 43 A pair of side-faced cutting edges 42 each extending linearly so as to gradually narrow the distance from each other as it goes to.

  Specifically, the pair of side surface cutting edges 42 are formed so as to be inclined from the outer side in the width direction toward the central side (inner side) gradually from the outer side in the extending direction of the insert body 31 toward the central side. A back taper is given.

  Further, the both end portions on the upper surface of the insert main body 31 are made to recede by one step from the central portion and have a substantially square shape, respectively, and form a pair of rake surfaces 33. The rake face 33 has a front cutting edge 41 and a pair of side cutting edges 42 on its outer peripheral edge other than the central side in the extending direction.

  5, 9, and 13, the peripheral surface connecting the upper surface and the lower surface of the outer surface of the insert main body 31 has a front flank 51 that is continuous with the front cutting edge 41 and a pair of side cutting edges 42, respectively. A pair of continuous side flank surfaces 52 are formed. The front flank 51 is formed to be inclined so as to gradually recede from the outer surface of the insert body 31 as it goes from the front cutting edge 41 toward the lower surface. Further, the side flank 52 is formed to be inclined so as to gradually recede from the outer surface of the insert body 31 as it goes from the side cutting edge 42 to the lower surface side. In the following description, the surface of the insert body 31 on which the front clearance surface 51 is formed is referred to as the front surface of the cutting insert 30, and the surface of the insert body 31 on which the side clearance surface 52 is formed is referred to as the side surface of the cutting insert 30.

  When the cutting insert 30 is mounted on the insert mounting seat 4 of the tool body 1, as shown in FIG. 3, the cutting edge 32A is arranged on the one side (lower side in FIG. 3) of the pair of cutting edges 32, A cutting edge 32B is arranged on the other side (upper side in FIG. 3). One cutting edge 32A protrudes from the tip surface 1A of the tip portion 3 of the tool body 1 toward the tip side, and is disposed to face the outer peripheral surface R of the work material W, and is grooved in the outer peripheral surface R. It is designed to be processed. Specifically, the tool body 1 projects one cutting edge 32A of the pair of cutting edges 32 from the distal end surface 1A of the distal end portion 3 toward the grooving direction indicated by the symbol YA in the Y direction, A cutting insert 30 is attached.

  3, 9, and 12, the direction indicated by C <b> 2 </ b> A is the work material in the pair of corner portions 43 </ b> A and 43 </ b> B (43 </ b> C and 43 </ b> D) in the width direction of the insert body 31 (the insert width axis C <b> 2 direction). The other width direction, which is the direction from one corner 43A (43C) located on the end face E side of W to the other corner 43B (43D) located on the opposite side to the end face E side, is shown. As shown in the front views of FIGS. 6 and 13, the insert width axis C <b> 2 of the cutting insert 30 is gradually inclined toward the rear side in the rotational direction WT of the work material W toward the other width direction C <b> 2 </ b> A. Yes.

  That is, in this cutting insert 30, the front cutting edge 41 of one cutting edge 32A is gradually inclined toward the rear side in the rotation direction WT of the work material W as it goes to the other width direction C2A. Specifically, as shown in FIG. 13, the cutting insert 30 gradually moves toward the rear side in the rotational direction WT as the front cutting edge 41 of the cutting edge 32 </ b> A moves from the one side surface 3 </ b> C side to the other side surface 3 </ b> D side of the tool body 1. In addition, the tool body 1 is inclined toward the upper surface 3A of the tool body 1, and the front cutting edge 41 is set to a negative (negative) angle. In addition, by this, in one cutting edge 32A, the corner portion 43B located on the other width direction C2A side of the pair of corner portions 43A and 43B has a rotational direction WT of the work material W with respect to the corner portion 43A. It is arranged on the rear side.

  In the present embodiment, the front cutting edge 41 of the cutting edge 32A is gradually inclined toward the rear side in the rotation direction WT of the work material W as it is separated from the end surface E along the rotation axis WO. Here, what is indicated by reference sign VS3 in FIGS. 5 and 13 represents a virtual tool plane including the corner portion 43A of the cutting edge 32A and the rotation axis WO. In FIG. 13, the angle θ2 formed by the front cutting edge 41 of the cutting edge 32A and the tool virtual plane VS3 is set within a range of 0 ° <θ2 ≦ 7 °. In the present embodiment, this θ2 is set to about 3 °, for example. Further, since the insert width axis C2 is parallel to the front cutting edge 41, it can be said that the angle θ2 is an angle formed by the insert width axis C2 and the tool virtual plane VS3. In the present embodiment, the tool virtual plane VS3 is arranged in the XY horizontal plane.

  3 and FIG. 5, the direction indicated by the reference symbol C <b> 1 </ b> A is one cutting edge from the other cutting edge 32 </ b> B of the pair of cutting edges 32 </ b> A and 32 </ b> B in the extending direction of the insert body 31 (in the direction of the insert longitudinal axis C <b> 1). One extending direction which is a direction toward 32A is shown. As shown in a side view of FIG. 5, the insert longitudinal axis C1 of the cutting insert 30 is inclined so as to gradually approach the tool virtual plane VS3 toward the one extending direction C1A.

  Specifically, as shown in FIG. 5, when viewed from one side 3 </ b> C side of the tool body 1, the insert longitudinal axis C <b> 1 gradually moves toward the lower surface side of the insert body 31 (up and down in FIG. 5) toward the one extending direction C <b> 1 </ b> A. It extends so as to approach the tool virtual plane VS3 from the direction (lower side in the Z direction) toward the upper surface side (upper side in the Z direction in FIG. 5). Thereby, the front cutting edge 41 of the cutting edge 32B is separated from the tool virtual plane VS3 toward the lower surface side of the insert main body 31 (the lower side in the Z direction in FIG. 5). The angle θ3 formed by the insert longitudinal axis C1 passing through the front cutting edges 41 and 41 of the cutting edges 32A and 32B and the tool virtual plane VS3 is set in a range of 0 ° <θ3 ≦ 10 °. In the present embodiment, this θ3 is set to about 3 °, for example.

  As shown in FIG. 7, the cutting insert 30 attached to the tool body 1 is moved in the one extending direction C1A from the other side where the cutting edge 32B is arranged to the one side where the cutting edge 32A is arranged. As it goes, it is arranged so as to be gradually inclined toward the upper surface 3A of the tool body 1.

  FIG. 3 is a top view of the cutting insert 30 as viewed from a direction orthogonal to the tool virtual plane VS3. The cutting insert 30 has an angle θ1 between the insert width axis C2 and the rotation axis WO of 0 ° ≦ It is set within the range of θ1 ≦ 0.5 ° and is mounted on the insert mounting seat 4. In the present embodiment, the θ1 is set to about 0 °. Thereby, in this top view, the angle formed by the front cutting edge 41 of the cutting edge 32A parallel to the insert width axis C2 and the rotation axis WO is also θ1 (= 0 °). In FIG. 3, the angle θ4 formed by the insert longitudinal axis C1 and the rotation axis WO is set within the range of 90 ° <θ4 <91 °. In the present embodiment, this θ4 is set to about 90.2 °. Specifically, the relationship between θ4 and θ1 is set such that 1 °> θ4−90 °> θ1.

  As shown in FIGS. 3 and 12, when viewed from the direction orthogonal to the tool virtual plane VS3 and facing the rake face 33, the cutting insert 30 is connected to the other width direction C2A of the other cutting edge 32B. The corner portion 43C located on the opposite side is disposed on the other width direction C2A side of the corner portion 43A located on the opposite side of the one cutting edge 32A. That is, the corner portion 43A located on the one side surface 3C side (left side in FIGS. 3 and 12) of the tool body 1 in the one cutting edge 32A is more than the corner portion 43C located on the one side surface 3C side in the other cutting edge 32B. Is also arranged on the side surface 3C side. In the present embodiment, the corner portion 43C located on the end surface E side in the cutting edge 32B is separated from the end surface E with respect to the corner portion 43A located on the end surface E side in the cutting edge 32A.

  Furthermore, by adjusting the above-described θ1 to θ4, as shown in FIGS. 14 to 16, the respective distances L1 from the corner portions 43A and 43B of the one cutting edge 32A to the rotation axis WO of the work material W, L2 can also be set to be the same. That is, in the cutting edge 32A, a radius of a virtual circle (distance L1) obtained by rotating the corner portion 43A around the rotation axis WO and a radius of a virtual circle obtained by rotating the corner portion 43B around the rotation axis WO ( The distance L2) may be set to be the same. The outer peripheries of these virtual circles coincide with the end on the end surface E side and the end opposite to the end surface E in the groove bottom D of the groove formed in the work material W, respectively.

  Further, the front cutting edge 41 of the cutting edge 32A has the same distance to the rotation axis WO as the distances L1 and L2 in any part disposed between the corner part 43A and the corner part 43B. Yes. Further, since the distances L1 and L2 can be obtained in advance corresponding to the radius of the groove bottom D to be grooved, the posture of the cutting insert 30 with respect to the work material W is set so as to satisfy these distances L1 and L2. You only have to set it.

  In the present embodiment, the cutting insert 30 of the tool body 1 having the above-described configuration is disposed close to the corner portion 43A of one of the cutting edges 32A so as to contact the end surface E of the work material W. The cutting edge 32 </ b> A is grooved with respect to the outer peripheral surface R by moving in the grooving direction YA toward the radially inner side of the work material W along the end surface E.

  As described above, according to the cutting edge exchange-type grooving tool 10 and the peripheral surface grooving method using the same according to the present embodiment, the tip 3 of the tool body 1 is moved to the outer peripheral surface R of the work material W. The front cutting edge 41 of one cutting edge 32A of the cutting insert 30 protruding toward the other side is made parallel to the insert width axis C2, and the workpiece W is gradually rotated toward the other width direction C2A. The negative angle with respect to the work material W is set so as to be inclined toward the rear side in the rotation direction WT. That is, since the front cutting edge 41 of the cutting edge 32A is inclined toward the rear side in the rotational direction WT gradually as it goes from the one side surface 3C side to the other side surface 3D side of the tool main body 1, it is stable with high accuracy. Cutting can be performed.

  Specifically, as described above, the cutting edge exchange type grooving tool 10 is supported in a state where the lower surface 2B and the other side surface 2D of the shank portion 2 of the tool body 1 are in contact with the mounting recess m of the machine tool M. . As shown in FIG. 8, during cutting, an external force (cutting resistance) FT received by one of the cutting edges 32A from the work material W is along an insert height axis C3 perpendicular to the front cutting edge 41 of the cutting edge 32A. This occurs from the top to the bottom. The cutting force FT includes a component force F1 in the Z direction and a component force F2 in the X direction. The component force F1 acts to press the lower surface 2B of the tool body 1 against the machine tool M, and the component force F2 acts to press the other side 2D of the tool body 1 against the machine tool M. As a result, the position of the cutting edge-replaceable grooving tool 10 with respect to the machine tool M at the time of cutting is stabilized, and highly accurate cutting can be performed stably.

  Further, the insert longitudinal axis C1 of the cutting insert 30 is inclined so as to gradually approach the tool virtual plane VS3 toward the one extending direction C1A, and extends toward the upper surface side of the insert body 31. That is, since the other cutting edge 32B is separated toward the lower surface side of the insert body 31 with respect to the tool virtual plane VS3, the one cutting edge 32A cuts sharply with respect to the outer peripheral surface R of the work material W. As a result, the sharpness can be sufficiently enhanced.

  Further, the other cutting edge 32B has a corner portion 43C located on the opposite side to the other width direction C2A, and the other cutting edge 32A has a corner portion 43A located on the opposite side to the other width direction C2A. It is arranged on the C2A side. Accordingly, as in the present embodiment, in the stepped portion U of the work material W having a multi-stage columnar shape, grooving processing is performed on the outer peripheral surface R of the work material W along the end surface E perpendicular to the rotation axis WO ( When performing outer grooving), the following operational effects are obtained. That is, one corner portion 43A of one cutting edge 32A of the cutting insert 30 is disposed close to the end surface E of the work material W, and the cutting insert 30 is placed along the end surface E in the grooving direction YA. When the grooving process is performed by moving to one end, it is ensured that one corner portion 43C of the other cutting edge 32B is separated from the end surface E, and the corner portion 43C contacts the end surface E and is damaged. To be prevented. Further, the contact prevents the other unused cutting edge 32B from being damaged. In this case, regardless of the diameter d1 of the large-diameter portion of the work material W shown in FIG. 3, one corner portion 43C of the other cutting edge 32B is separated from the end surface E, and the corner portion 43C is the end surface. It is reliably prevented that the E is touched and damaged.

  Further, when attention is paid to the groove bottom D of the work material W to be cut by one of the cutting edges 32A, the rotation direction in which the work material W is gradually rotated as the insert width axis C2 of the cutting insert 30 moves toward the other width direction C2A. Inclining toward the rear side of WT, inclining toward the upper surface side of the insert body 31 so that the insert longitudinal axis C1 approaches the virtual tool plane VS3 toward the one extending direction C1A, and One groove portion 43C of the other cutting edge 32B is disposed on the other width direction C2A side of the other cutting edge 32A than the one corner portion 43A of the other cutting edge 32A. It is formed with an inclination close to parallel to the rotation axis WO. That is, the angle α of the groove bottom D in FIG. 29 is formed to be relatively small, and the machining accuracy of the groove cut into the work material W is increased.

  Further, the pair of side surface cutting edges 42, 42 provided in each of the cutting edges 32A, 32B are formed to be inclined so as to gradually narrow each other as they go from the outside in the extending direction of the insert body 31 toward the center side. Therefore, the processing accuracy of the groove wall in the processed groove is ensured. That is, even if the mounting posture of the cutting insert 30 with respect to the tool body 1 is set as described above, the one cutting edge 32A is opposite to the end surface E side of the workpiece W (that is, the other width direction C2A side). Therefore, the side cutting edge 42 disposed on the workpiece W does not come into contact with the opening edge of the groove wall on the opposite side of the groove formed in the work material W.

  In addition, when the cutting insert 30 is viewed from a direction orthogonal to the tool virtual plane VS3, an angle θ1 formed by the insert width axis C2 along the width direction of the insert body 31 and the rotation axis WO of the workpiece W is 0 ° ≦ θ1. ≦ 0.5 ° is set. Accordingly, the angle (θ4-90 °) at which the insert longitudinal axis C1 along the extending direction of the insert body 31 is inclined with respect to the end surface E of the work material W is close to the set value of θ1. It is set to a value slightly larger than the θ1. In other words, the posture of the cutting insert 30 with respect to the tool body 1 is arranged substantially in parallel with the extending direction of the insert body 31 (insert longitudinal axis C1) being substantially inclined with respect to the end surface E of the work material W. In addition, as described above, the corner portion 43C of the other cutting edge 32B can be reliably separated from the end face E. Therefore, the machining accuracy of the groove bottom D of the work material W that has been grooved is more reliably increased.

  In the outer diameter grooving of the present embodiment, when the distances L1 and L2 from the pair of corner portions 43A and 43B of the one cutting edge 32A to the rotation axis WO of the work material W are set to be the same as each other. Can form the groove bottom D of the work material W to be cut with one of the cutting edges 32A in parallel to the rotation axis WO. Therefore, the finishing accuracy of the groove of the work material W is sufficiently ensured.

  In addition, since the angle θ4 formed by the insert longitudinal axis C1 and the rotation axis WO of the workpiece W is set to 90 ° <θ4 <91 ° when viewed from the direction orthogonal to the tool virtual plane VS3, Even when grooving is performed on the outer peripheral surface R along the end surface E of the stepped portion U using the cutting edge 32A, the corner portion 43C on the end surface E side of the other cutting edge 32B is surely secured from the end surface E. While being separated, the processing accuracy of the groove bottom D is sufficiently secured.

  That is, when the angle θ4 is set to 91 ° or more, when forming a deep groove, the side cutting edge 42 disposed on the other side 3D side of the tool body 1 in one cutting edge 32A is a processed groove. There is a risk of contact with the opening edge. In addition, the groove bottom D of the groove is relatively inclined with respect to the rotation axis WO, and the groove processing accuracy cannot be ensured.

  In this way, in the outer diameter grooving using the above-described blade edge replaceable grooving tool 10, the annular ring adjacent to the small diameter portion of the outer peripheral surface R in the stepped portion U of the work material W having a multistage cylindrical shape. Even if the end face E which is formed of a surface and is orthogonal to the rotation axis WO is formed, the outer diameter grooving with high accuracy can be performed regardless of the position of the outer peripheral surface R to be grooved.

(Second Embodiment)
Next, a cutting edge exchange type grooving tool 20 according to a second embodiment of the present invention will be described with reference to FIGS. 17 to 22. In addition, the same code | symbol is attached | subjected to the same member as above-mentioned embodiment, and the description is abbreviate | omitted.

  The cutting edge-replaceable grooving tool 20 of the present embodiment includes a tool body 1 that is formed in an axial shape and has a substantially circular cross section perpendicular to the center axis TO, and a tip 3 that extends along the center axis TO of the tool body 1. It has a cutting insert 30 that is detachably mounted and projects a cutting edge 32A from the outer peripheral surface 1B of the tool body 1 toward the side. That is, as shown in FIG. 18, when viewed from the direction orthogonal to the tool virtual plane VS <b> 3, the cutting edge replaceable grooving tool 20 of the present embodiment uses the insert longitudinal axis C <b> 1 of the cutting insert 30 as the center axis TO of the tool body 1. The cutting insert 30 is disposed along the tip surface of the tip portion 3 of the tool body 1. In FIG. 18, the tool body 1 is disposed along the X direction so as to extend substantially parallel to the rotation axis WO of the work material W, and one cutting edge 32A is directed in the grooving direction YA. Protruding. Although not shown, when the cutting edge exchange type grooving tool 20 is mounted in the mounting recess m of the machine tool M, the base end portion of the tool body 1 is supported in contact with the mounting recess m.

  This blade edge exchange type grooving tool 20 performs an inner diameter grooving process on a substantially cylindrical work material W. In the work hole H having a cylindrical hole shape in the work material W, an inner face (end face) B formed of a circular plane orthogonal to the rotation axis WO of the work material W is formed in the innermost part. . The back surface B is adjacent to the inner peripheral surface (circumferential surface) S of the processing hole H. The blade-tip-exchange-type grooving tool 20 inserts the tip 3 of the tool body 1 into a machining hole H formed around the rotational axis WO in the work material W that rotates in the rotational direction WT about the rotational axis WO. In the state where the corner portion 43A of one of the cutting edges 32A is disposed close to the back surface B of the work material W, the cutting insert 30 is arranged along the back surface B in the radial direction of the work material W. Moving outward in the grooving direction YA, the cutting edge 32A grooves the inner peripheral surface S of the processing hole H facing the rotation axis WO side. In the present embodiment, the rotation direction WT of the work material W is set opposite to that in the first embodiment.

  In the cutting edge exchange type grooving tool 20 of the present embodiment, of the pair of corner portions 43A and 43B of one cutting edge 32A, the corner portion 43B located on the other width direction C2A side is in relation to the corner portion 43A. The workpiece W is arranged on the rear side in the rotation direction WT. That is, in this cutting insert 30, the front cutting edge 41 of one cutting edge 32A is parallel to the insert width axis C2, and the rotation direction WT of the workpiece W gradually increases toward the other width direction C2A. It inclines toward the rear side of. Specifically, the front cutting edge 41 of the cutting edge 32A is inclined toward the rear side in the rotational direction WT gradually from the distal end side of the tool body 1 toward the proximal end side (that is, the other width direction C2A side), The front cutting edge 41 is set to a negative (negative) angle. In the present embodiment, the front cutting edge 41 of the cutting edge 32A is gradually inclined toward the rear side in the rotation direction WT of the work material W as it is separated from the back surface B along the rotation axis WO.

  Further, as shown in a side view of the cutting insert 30 in FIG. 19 (a front view in the tool body 1), the insert longitudinal axis C1 of the cutting insert 30 gradually moves toward the one extending direction C1A. It inclines so that it may approach tool virtual plane VS3 toward the upper surface side (above the up-down direction (Z direction) in FIG. 19). Thereby, the front cutting edge 41 of the cutting edge 32B is spaced apart from the tool virtual plane VS3 toward the lower surface side of the insert main body 31 (the lower side in the Z direction in FIGS. 19 and 22).

  18 and 20, when viewed from the direction orthogonal to the tool virtual plane VS3 and facing the rake face 33, the cutting insert 30 is connected to the other width direction C2A of the other cutting edge 32B. The corner portion 43C located on the opposite side is disposed on the other width direction C2A side of the corner portion 43A located on the opposite side of the one cutting edge 32A. That is, the corner portion 43A located on the distal end side (left side in FIG. 20) of the tool body 1 in one cutting edge 32A is closer to the distal end side than the corner portion 43C located on the distal end side in the other cutting edge 32B. Has been placed. In the present embodiment, the corner portion 43C located on the back surface B side in the cutting edge 32B is separated from the back surface B with respect to the corner portion 43A located on the back surface B side in the cutting edge 32A.

  In addition, the angles θ1 to θ4 in the blade edge replaceable grooving tool 20 are respectively set to the same numerical ranges as the angles θ1 to θ4 in the blade edge replaceable grooving tool 10 described above.

  According to the cutting edge-replaceable grooving tool 20 according to the present embodiment, in the cylindrical hole-shaped machining hole H formed in the workpiece W, the workpiece W along the back surface B orthogonal to the rotation axis WO. Even in the case of grooving (inner diameter grooving) on the inner peripheral surface S of the inner peripheral surface S, the corner portion 43C of the cutting edge 32B is separated from the inner surface B regardless of the position of the inner peripheral surface S to be grooved, The corner portion 43C is reliably prevented from coming into contact with the back surface B and being damaged, and a highly accurate inner diameter grooving can be performed. Further, the contact prevents the other unused cutting edge 32B from being damaged.

  Further, since the front cutting edge 41 of the one cutting edge 32A is set to the negative angle as described above, the component force of the cutting resistance FT received by the cutting edge 32A during the cutting process is along the central axis TO. The base end side portion of the tool body 1 acts in a direction to press against the mounting recess m of the machine tool M. As a result, the position of the cutting edge exchange-type grooving tool 20 with respect to the machine tool M at the time of cutting is stabilized, and highly accurate cutting can be performed stably. In particular, in a tool that is cantilevered by the machine tool M, such as the blade-tip exchange grooving tool 20, the component force that pushes the shank portion 2 toward the proximal end realizes stable and highly accurate cutting. Let

In addition, this invention is not limited to the above-mentioned embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.
For example, in the above-described embodiment, the insert mounting seat 4 is formed at the tip 3 of the tool body 1. However, the present invention is not limited to this, and a detachable head is attached to the tip 3. In addition, the insert mounting seat 4 may be formed on the head portion. Moreover, the shape of the tool main body 1 described above is not limited to that described in the above embodiment.

  Further, the pair of corner portions 43 of the cutting edge 32 is not limited to the shape described in the above embodiment. 23 and 24 show a modification of the corner portion 43. FIG. In FIG. 23, the corner portion 43 has a convex curve shape and includes a first corner blade 44 that smoothly connects the front cutting edge 41 and the side cutting edge 42. The corner portion 43A of the one cutting edge 32A is directed from the extension line VL1 of the front cutting edge 41 adjacent to the corner portion 43A to the extension line VL1 from the outer edge portion of the insert body 31 in the first corner blade 44 in the width direction. An intersection point P with the extended vertical line VL2 is arranged on the tool virtual plane VS3. In this case, chipping of the edge of each corner portion 43 is prevented.

  24, the corner portion 43 includes a first corner blade 44, an end portion on the center side (upper side in FIG. 24) along the extending direction of the insert body 31 in the first corner blade 44, and a side cutting blade. And a second corner blade 45 having a linear shape that connects the first and second corner blades 42 to each other. When the cutting insert 30 is viewed from the direction orthogonal to the tool virtual plane VS3, the second corner blade 45 extends so as to be orthogonal to the rotation axis WO of the work material W, and extends to the end surface E or the back surface B. It is formed so as to extend in parallel. In this case, the second corner blade 45 exposes the groove wall of the work material W cut by the front cutting edge 41 and the first corner blade 44 of the one cutting edge 32A, and the finishing accuracy of the groove wall is increased. It is done.

  In the above-described embodiment, the cutting edge 32A of the cutting insert 30 is grooved into the peripheral surfaces R and S along the end surfaces E and B of the work material W. However, the present invention is not limited to this. is not. For example, the peripheral surfaces R and S separated from the end surfaces E and B of the work material W may be grooved. According to the embodiment of the present invention, even when any of the peripheral surfaces R and S adjacent to the end surfaces E and B of the work material W or the separated peripheral surfaces R and S is grooved, high precision is achieved. Can be cut.

DESCRIPTION OF SYMBOLS 1 Tool main body 1A Tip surface 1B Outer peripheral surface of tool main body 2C One side surface of shank part 2D Other side surface of shank part 3 Tip part 3C One side surface of tip part 3D Other side surface of tip part 10, 20 Cutting edge type grooving tool 30 Cutting Insert 31 Insert body 32 Cutting edge 32A One cutting edge 32B The other cutting edge 41 Front cutting edge 42 Side cutting edge 43 Corner part 43A One corner part located on the opposite side to the other width direction C2A in one cutting edge 43B The other corner portion located on the other width direction C2A side in the one cutting edge 43C The one corner portion 43D located on the opposite side of the other width direction C2A in the other cutting edge 43D The other width in the other cutting edge The other corner portion located on the direction C2A side 44 First corner blade 45 Second corner blade B Back surface (end surface)
C1 insert longitudinal axis (extending direction of the insert body)
C1A One extending direction, which is a direction from the other cutting edge toward one cutting edge in the extending direction of the insert main body C2 Insert width axis (width direction of the insert main body)
C2A Of the width direction of the insert body, the other width direction is the direction from one corner portion toward the other corner portion. C3 Insert height axis (height direction of the insert body)
E End surface L1 Distance from one corner located on the opposite side of the other width direction C2A to the rotation axis in one cutting edge L2 From the other corner located on the other width direction C2A side in one cutting edge Distance to rotation axis P Intersection of extension line VL1 and perpendicular line VL2 R Outer peripheral surface (peripheral surface) of work material
S Inner peripheral surface (peripheral surface)
TO Central axis VL1 of tool body Extension line of front cutting edge VL2 Perpendicular line extending from outer edge of first corner blade toward extension line VL1 VS1 Insert virtual plane VS3 Tool virtual plane W Work material WO Rotation axis of work material WT Rotation direction of work material YA Groove direction
Z Vertical direction θ1 Angle formed by the insert width axis and the rotation axis of the work material θ2 Angle formed by the front cutting edge (or insert width axis) of one cutting edge and the virtual tool plane

Claims (17)

A cutting insert having a cutting edge protruding toward the peripheral surface of the work material rotating about the rotation axis, and a tool body having a shaft shape and having the cutting insert detachably attached to the tip. And a cutting edge exchange type grooving tool for grooving the peripheral surface with the cutting edge,
The cutting insert includes a pair of cutting edges on the upper surface of the insert body at both ends in the extending direction of the rod-shaped insert body, and the width direction perpendicular to the center of the insert body and the extending direction Are formed rotationally symmetric with respect to the insert height axis perpendicular to the extending direction and the width direction through the center of the insert, and plane symmetric with respect to the insert virtual plane that includes the insert height axis and is perpendicular to the extending direction.
The cutting edge is formed at an edge of the insert body in the extending direction and extends along the width direction, and a pair of cutting edges disposed at both ends of the front cutting edge and projecting in the width direction. A corner portion, and a pair of side cutting edges each extending so as to gradually narrow the distance from each other toward the center side of the insert body along the extending direction from the corner portion,
The tool body has one cutting edge of the pair of cutting edges protruding toward the grooving direction, and the cutting insert is mounted,
The cutting insert is arranged on the tool body so as to be along one side surface facing the side of the tool body,
The grooving direction is a direction toward the tip side of the tool body,
The cutting insert is
One corner portion located in a direction in which the insert width axis passing through the center in the extending direction of the insert body and extending along the width direction is separated from the center axis of the tool body in the pair of corner portions. Gradually inclines toward the upper side of the tool body as it goes in the other width direction, which is the direction from the other corner portion,
An insert longitudinal axis passing through the center in the width direction of the insert body and extending in the extending direction is inclined with respect to a virtual tool plane including one corner portion of the one cutting edge and perpendicular to the vertical direction of the tool body. And, in the extending direction, gradually approach the tool virtual plane as it goes from the other cutting edge of the pair of cutting edges toward the one cutting edge. Extending toward the upper side of the tool body ,
One corner portion located on the opposite side to the other width direction in the other cutting edge is disposed on the other width direction side than the one corner portion in the one cutting edge , and
The one corner portion located in a direction away from the central axis of the tool body from the other corner portion of the other cutting edge is closer to the central axis than the other corner portion of the one cutting edge. The blade edge exchange type grooving tool, which is arranged in a direction approaching the central axis with respect to the one corner portion located in the separating direction .   A cutting insert having a cutting edge protruding toward the peripheral surface of the work material rotating about the rotation axis, and a tool body having a shaft shape and having the cutting insert detachably attached to the tip. And a cutting edge exchange type grooving tool for grooving the peripheral surface with the cutting edge,
  The cutting insert includes a pair of cutting edges on the upper surface of the insert body at both ends in the extending direction of the rod-shaped insert body, and the width direction perpendicular to the center of the insert body and the extending direction Are formed rotationally symmetric with respect to the insert height axis perpendicular to the extending direction and the width direction through the center of the insert, and plane symmetric with respect to the insert virtual plane that includes the insert height axis and is perpendicular to the extending direction.
  The cutting edge is formed at an edge of the insert body in the extending direction and extends along the width direction, and a pair of cutting edges disposed at both ends of the front cutting edge and projecting in the width direction. A corner portion, and a pair of side cutting edges each extending so as to gradually narrow the distance from each other toward the center side of the insert body along the extending direction from the corner portion,
  The tool body has one cutting edge of the pair of cutting edges protruding toward the grooving direction, and the cutting insert is mounted,
  The cutting insert is disposed on the tool body so as to be along a tip surface facing the tip side of the tool body,
  The grooving direction is a direction away from the center axis of the tool body,
  The cutting insert is
  The insert width axis along the width direction passing through the center in the extending direction of the insert main body, and the other corner from one corner portion located on the tip end side of the tool main body in the pair of corner portions in the width direction. Gradually inclines toward the upper side of the tool body as it goes in the other width direction, which is a direction toward the part,
  An insert longitudinal axis passing through the center in the width direction of the insert body and extending in the extending direction is inclined with respect to a virtual tool plane including one corner portion of the one cutting edge and perpendicular to the vertical direction of the tool body. And, in the extending direction, gradually approach the tool virtual plane as it goes from the other cutting edge of the pair of cutting edges toward the one cutting edge. Extending toward the upper side of the tool body,
  One corner portion located on the opposite side to the other width direction in the other cutting edge is disposed on the other width direction side than the one corner portion in the one cutting edge, and
  The one corner portion located closer to the tip side of the tool body than the other corner portion of the other cutting edge is located closer to the tip side of the tool body than the other corner portion of the one cutting edge. The blade edge exchange type grooving tool is arranged on the base end side of the tool main body with respect to the one corner portion. It is a blade exchange type grooving tool according to claim 1 or 2 ,
An angle θ1 formed by the insert width axis and the rotation axis when the cutting insert is viewed from a direction orthogonal to the tool imaginary plane is set to 0 ° ≦ θ1 ≦ 0.5 °. Replaceable grooving tool. It is a blade exchange type grooving tool according to claim 1 or 3 ,
The peripheral surface is an outer peripheral surface facing the opposite side of the rotation axis of the work material,
The one of the cutting edges is an outer diameter grooving process with respect to the outer peripheral surface. It is a blade exchange type grooving tool according to claim 4 ,
In the tool body, the cutting insert is arranged along one side surface facing the side of the tool body, and the one cutting edge is projected from the tip surface of the tip part toward the tip side. And
The cutting insert is gradually inclined toward the upper side of the tool body as the front cutting edge of the one cutting edge is directed from the one side surface toward the other side surface facing the side opposite to the one side surface. Then, the cutting edge exchange type grooving tool characterized by being set to a negative angle. It is a blade exchange type grooving tool according to claim 2 or 3 ,
The peripheral surface is an inner peripheral surface facing the rotation axis side of the work material,
The one cutting edge is subjected to an inner diameter grooving process with respect to the inner peripheral surface. It is a blade exchange type grooving tool according to claim 6,
The tool body protrudes the one cutting edge from the outer peripheral surface of the tip portion to the side,
The cutting insert is set to a negative angle by gradually inclining the upper cutting edge of the one cutting edge toward the upper side of the tool body gradually from the distal end side to the proximal end side of the tool body . A blade-exchangeable grooving tool characterized by that.   It is a cutting edge exchange type grooving tool according to any one of claims 1 to 7,
  The distance between the pair of corner portions and the rotation axis of the one cutting edge is set to be the same as each other, and the blade edge exchange type grooving tool is characterized. It is a blade exchange type grooving tool according to any one of claims 1 to 8 ,
The corner portion has a convex curved first corner blade,
The one corner portion of the one cutting edge includes an extension line of the front cutting edge adjacent to the corner portion and a perpendicular extending from the outer edge portion in the width direction of the first corner blade toward the extension line. The blade tip exchange type grooving tool is characterized in that the intersecting points are arranged on the virtual tool plane. It is a blade exchange type grooving tool according to claim 9 ,
The corner portion has a linear second corner blade that connects the end portion on the center side in the extending direction of the insert body in the first corner blade and the side surface cutting blade,
The cutting edge replacement type grooving characterized in that the second corner blade extends so as to be orthogonal to the rotation axis of the work material when the cutting insert is viewed from a direction orthogonal to the tool virtual plane. tool. A cutting insert having a cutting edge projecting toward a peripheral surface of a work material rotating about a rotation axis; and a tool body having a shaft shape, the cutting insert being detachably mounted at a tip portion. A peripheral grooving method for grooving the peripheral surface of the work material with the cutting edge using a blade exchange type grooving tool,
The cutting insert includes a pair of cutting edges on the upper surface of the insert body at both ends in the extending direction of the rod-shaped insert body, and the width direction perpendicular to the center of the insert body and the extending direction Are formed rotationally symmetric with respect to the insert height axis perpendicular to the extending direction and the width direction through the center of the insert, and plane symmetric with respect to the insert virtual plane that includes the insert height axis and is perpendicular to the extending direction.
The cutting edge is formed at an edge of the insert body in the extending direction and extends along the width direction, and a pair of cutting edges disposed at both ends of the front cutting edge and projecting in the width direction. A corner portion, and a pair of side cutting edges each extending so as to gradually narrow the distance from each other toward the center side of the insert body along the extending direction from the corner portion,
The cutting insert is mounted on the tool body with one of the pair of cutting edges projecting in the grooving direction, and the one cutting edge is moved along the grooving direction. When grooving the peripheral surface by
The other width that is the direction from one corner portion to the other corner portion of the pair of corner portions in the width direction, with the insert width axis passing through the center in the extending direction of the insert body and extending along the width direction. is inclined toward the opposite side to the gradual rotation direction of rotation of the workpiece as it goes in the direction,
The insert longitudinal axis along the extending direction passing through the center in the width direction of the insert main body is inclined with respect to a virtual tool plane including one corner portion of the one cutting edge and the rotation axis, and the extension of direction, opposite to the rotation direction gradually so as to approach to the tool virtual plane as it goes to the pair of the one extending direction is a direction toward the one cutting edge from the other of the cutting edge in the cutting edge Extend towards
The peripheral surface of the work material is an outer peripheral surface facing outward in the radial direction perpendicular to the rotation axis,
Of the work material, the one corner portion of the other cutting edge is raised with respect to an end surface that rises toward the outside in the radial direction adjacent to the outer peripheral surface and is perpendicular to the rotation axis. The circumferential grooving method according to claim 1, wherein the circumferential grooving method is arranged apart from the one corner portion cut into the outer peripheral surface along the end surface of the one cutting edge. A cutting insert having a cutting edge projecting toward a peripheral surface of a work material rotating about a rotation axis; and a tool body having a shaft shape, the cutting insert being detachably mounted at a tip portion. A peripheral grooving method for grooving the peripheral surface of the work material with the cutting edge using a blade exchange type grooving tool,
The cutting insert includes a pair of cutting edges on the upper surface of the insert body at both ends in the extending direction of the rod-shaped insert body, and the width direction perpendicular to the center of the insert body and the extending direction Are formed rotationally symmetric with respect to the insert height axis perpendicular to the extending direction and the width direction through the center of the insert, and plane symmetric with respect to the insert virtual plane that includes the insert height axis and is perpendicular to the extending direction.
The cutting edge is formed at an edge of the insert body in the extending direction and extends along the width direction, and a pair of cutting edges disposed at both ends of the front cutting edge and projecting in the width direction. A corner portion, and a pair of side cutting edges each extending so as to gradually narrow the distance from each other toward the center side of the insert body along the extending direction from the corner portion,
The cutting insert is mounted on the tool body with one of the pair of cutting edges projecting in the grooving direction, and the one cutting edge is moved along the grooving direction. When grooving the peripheral surface by
The other width that is the direction from one corner portion to the other corner portion of the pair of corner portions in the width direction, with the insert width axis passing through the center in the extending direction of the insert body and extending along the width direction. is inclined toward the opposite side to the gradual rotation direction of rotation of the workpiece as it goes in the direction,
The insert longitudinal axis along the extending direction passing through the center in the width direction of the insert main body is inclined with respect to a virtual tool plane including one corner portion of the one cutting edge and the rotation axis, and the extension of direction, opposite to the rotation direction gradually so as to approach to the tool virtual plane as it goes to the pair of the one extending direction is a direction toward the one cutting edge from the other of the cutting edge in the cutting edge Extend towards
The peripheral surface of the work material is an inner peripheral surface facing inward in the radial direction perpendicular to the rotation axis,
Of the work material, the one corner portion of the other cutting edge with respect to an end surface that rises inward in the radial direction adjacent to the inner peripheral surface and is perpendicular to the rotation axis. Is disposed at a distance from the one corner portion cut into the inner circumferential surface along the end surface of the one cutting edge.   A circumferential grooving method according to claim 11 or 12,
  An angle θ1 formed by the insert width axis and the rotation axis is set to 0 ° ≦ θ1 ≦ 0.5 ° when the cutting insert is viewed from a direction orthogonal to the tool virtual plane. Grooving method. It is a peripheral surface grooving processing method as described in any one of Claims 11-13,
The circumferential grooving method according to claim 1, wherein the front cutting edge of the one cutting edge is gradually inclined toward the opposite side of the rotation direction as the distance from the end face is set to a negative angle.   It is a peripheral surface grooving processing method as described in any one of Claims 11-14,
  The circumferential grooving method according to claim 1, wherein distances from the pair of corner portions to the rotation axis of the one cutting edge are set to be the same.   A circumferential grooving method according to any one of claims 11 to 15,
  The corner portion has a convex curved first corner blade,
  The one corner portion of the one cutting edge includes an extension line of the front cutting edge adjacent to the corner portion and a perpendicular extending from the outer edge portion in the width direction of the first corner blade toward the extension line. The circumferential surface grooving method according to claim 1, wherein the intersection point is arranged on the tool virtual plane.   The peripheral surface grooving method according to claim 16,
  The corner portion has a linear second corner blade that connects the end portion on the center side in the extending direction of the insert body in the first corner blade and the side surface cutting blade,
  The circumferential grooving is characterized in that the second corner blade is extended so as to be orthogonal to the rotation axis of the work material when the cutting insert is viewed from a direction orthogonal to the tool virtual plane. Processing method.

Images