Cutting edge replacement type groove forming tool and end face groove forming method

An end face grooving method for grooving on an end face of a workpiece with an insert of an insert-replaceable grooving tool including a cutting insert, a cutting edge of which protrudes toward the end face of the workpiece rotating around a rotation axis line, and a tool body which has a shaft shape, the cutting insert being detachably mounted on an end portion of the tool body,

• wherein the cutting insert includes:
• an insert body which has a bar shape, and
• a pair of cutting edges which is formed on an upper surface of the insert body in both ends of a longitudinal direction of the insert body,
• wherein the cutting insert is formed so as to be rotationally symmetric with respect to an axis line of a height direction, which is perpendicular with respect to an axis line of the longitudinal direction passing through the center of the pair of cutting edges and extending in the longitudinal direction, and with respect to an axis line of a traverse direction extending in the traverse direction perpendicular to the longitudinal direction and passing through the centers, at the centers, and the cutting insert is formed so as to be planarly symmetric with respect to a virtual plane of the insert which includes the axis line of the height direction and is perpendicular to the longitudinal direction,
• wherein the cutting edge includes:
• a front cutting edge which is formed on an end edge in the longitudinal direction of the insert body and extends along the traverse direction,
• a pair of corner portions which is disposed on both ends of the front cutting edge and is formed so as to protrude in the traverse direction, and
• a pair of side surface cutting edges which extends so as to gradually narrow the mutual gap moving from the corner portions toward the centers along the longitudinal direction,
• wherein when performing a grooving with respect to the end face by disposing the cutting insert along one side surface of the tool body, protruding one cutting edge in the pair of cutting edges in a grooving direction from an end face of the end portion, and moving the one cutting edge in the grooving direction,
• the end face grooving method comprises:
• the steps of:
• gradually inclining the axis line of the traverse direction toward the front of a rotational direction around which the workpiece rotates moving toward a first traverse direction which is a direction from one corner portion positioned on the one side surface side of the tool body in the pair of corner portions toward the other corner portion in the traverse direction;
• inclining the axis line of the longitudinal direction with respect to a virtual plane of the tool including the other corner portion of the one cutting edge and the rotation axis line, and extending the axis line of the longitudinal direction toward a lower surface side of the insert body so as to gradually approach the virtual plane of the tool moving toward a first longitudinal direction which is a direction from the other cutting edge toward the one cutting edge of the pair of cutting edges in the longitudinal direction;
• and
• disposing the one corner portion in the other cutting edge further toward the first traverse direction than the one corner portion in the one cutting edge.

An insert-replaceable grooving tool for grooving on an end face of a workpiece with an insert, comprising:

• a cutting insert, a cutting edge of which protrudes toward the end face of the workpiece rotating around a rotation axis line, and
• a tool body which has a shaft shape, the cutting insert being detachably mounted on an end portion of the tool body,
• wherein the cutting insert includes:
• an insert body which has a bar shape;
• and
• a pair of cutting edges which is formed on an upper surface of the insert body in both ends of a longitudinal direction of the insert body,
• wherein the cutting insert is formed so as to be rotationally symmetric with respect to an axis line of a height direction, which is perpendicular with respect to an axis line of the longitudinal direction passing through the center of the pair of cutting edges and extending in the longitudinal direction, and with respect to an axis line of a traverse direction extending in the traverse direction perpendicular to the longitudinal direction and passing through the centers, at the centers, and the cutting insert is formed so as to be planarly symmetric with respect to a virtual plane of the insert which includes the axis line of the height direction and is perpendicular to the longitudinal direction,
• wherein the cutting edge includes:
• a front cutting edge which is formed on an end edge in the longitudinal direction of the insert body and extends along the traverse direction;
• a pair of corner portions which is disposed on both ends of the front cutting edge and is formed so as to protrude in the traverse direction;
• and
• a pair of side surface cutting edges which extends so as to gradually narrow the mutual gap moving from the corner portions toward the centers along the longitudinal direction,
• wherein the cutting insert is disposed along one side surface of the tool body,
• one cutting edge in the pair of cutting edges protrudes toward a grooving direction from an end face of the end portion,
• the axis line of the traverse direction is gradually inclined toward the back of a rotational direction around which the workpiece rotates moving toward a first traverse direction which is a direction from one corner portion positioned on the one side surface side of the tool body in the pair of corner portions toward the other corner portion in the traverse direction,
• the axis line of the longitudinal direction is inclined with respect to a virtual plane of the tool including the one corner portion and the rotation axis line of the one cutting edge, and extends toward an upper surface side of the insert body so as to gradually approach the virtual plane of the tool moving toward a first longitudinal direction which is a direction from the other cutting edge toward the one cutting edge of the pair of cutting edges in the longitudinal direction, and
• the one corner portion in the other cutting edge is disposed further toward the first traverse direction than the one corner portion in the one cutting edge.

An end face grooving method for grooving on an end face of a workpiece with an insert of an insert-replaceable grooving tool including a cutting insert, a cutting edge of which protrudes toward the end face of the workpiece rotating around a rotation axis line, and a tool body which has a shaft shape, the cutting insert being detachably mounted on an end portion of the tool body,

• wherein the cutting insert includes:
• an insert body which has a bar shape;
• and
• a pair of cutting edges which is formed on an upper surface of the insert body in both ends of a longitudinal direction of the insert body,
• wherein the cutting insert is formed so as to be rotationally symmetric with respect to an axis line of a height direction, which is perpendicular with respect to an axis line of the longitudinal direction passing through the center of the pair of cutting edges and extending in the longitudinal direction, and with respect to an axis line of a traverse direction extending in the traverse direction perpendicular to the longitudinal direction and passing through the centers, at the centers, and the cutting insert is formed so as to be planarly symmetric with respect to a virtual plane of the insert which includes the axis line of the height direction and is perpendicular to the longitudinal direction,
• wherein the cutting edge includes:
• a front cutting edge which is formed on an end edge in the longitudinal direction of the insert body and extends along the traverse direction;
• a pair of corner portions which is disposed on both ends of the front cutting edge and is formed so as to protrude in the traverse direction;
• and
• a pair of side surface cutting edges which extends so as to gradually narrow the mutual gap moving from the corner portions toward the centers along the longitudinal direction,
• wherein when performing a grooving with respect to the end face by disposing the cutting insert along one side surface of the tool body, protruding one cutting edge in the pair of cutting edges in a grooving direction from an end face of the end portion, and moving the one cutting edge in the grooving direction,
• the end face grooving method comprises:
• gradually inclining the axis line of the traverse direction toward the back of a rotational direction around which the workpiece rotates moving toward a first traverse direction which is a direction from one corner portion positioned on the one side surface side of the tool body in the pair of corner portions toward the other corner portion in the traverse direction;
• inclining the axis line of the longitudinal direction with respect to a virtual plane of the tool including the one corner portion and the rotation axis line in the one cutting edge, and extending the axis line of the longitudinal direction toward an upper surface side of the insert body so as to gradually approach the virtual plane of the tool moving toward a first longitudinal direction which is a direction from the other cutting edge toward the one cutting edge of the pair of cutting edges in the longitudinal direction;
• and
• disposing the one corner portion in the other cutting edge further toward the first traverse direction than the one corner portion in the one cutting edge.