Cutting insert and indexable insert-type cutting tool

Patent metadata

Field	Value
Publication number	US-9511427-B2
Application number	US-201414230459-A
Country	US
Kind code	B2
Filing date	Mar 31, 2014
Priority date	Oct 4, 2011
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

A cutting insert and an indexable insert-type cutting tool includes a cutting edge ( 6 A) formed on each of a pair of side ridge portions of at least one of the side faces, wherein an insert main body ( 1 ) is formed in the shape of having front-back inversion symmetry which is 180° rotationally symmetrical with respect to a line of symmetry (N) passing through the center of the side faces; a flank face adjacent to the cutting edge ( 6 A) is formed on the side face in the vicinity of each of the pair of polygonal faces ( 2 ); each of the flank faces is formed in the shape of a twisted face; the pair of side ridge portions on which the cutting edge ( 6 A) is formed intersect each other in such a manner that the second corner portion (B) of one side ridge portion protrudes outside the other side ridge portion.

First claim

What is claimed is:

1. A cutting insert which is attached in a detachable manner to an insert seat of an indexable insert-type cutting tool, the cutting insert comprises:
a polygonal plate-like insert main body having a pair of polygonal faces and a plurality of side faces arranged at the periphery thereof,
wherein a cutting edge is formed on a side ridge portion of the polygonal face, and the insert main body is formed in the shape of having front-back inversion symmetry with respect to the pair of polygonal faces,
of the pair of polygonal faces, when one polygonal face is used as a rake face, the other polygonal face is used as a seating face which is seated on a base of the insert seat,
a pair of contact surfaces disposed along each of a pair of imaginary flat faces of the cutting insert are formed on each of the pair of polygonal faces,
the pair of contact surfaces are allowed to be individually in contact with a pair of contacted surfaces formed on the base of the insert seat, when the polygonal face on which the pair of contact surfaces are formed is used as the seating face,
an attachment hole is formed on the insert main body at the center of an insert central line which connects centers of the pair of polygonal faces,
the pair of imaginary flat faces of the cutting insert on which the pair of contact surfaces are disposed include one imaginary straight line of the cutting insert and are also arranged in a direction intersecting with each other in an X-letter shape, with setting the imaginary straight line of the cutting insert as an intersection point, when seen in a direction along the imaginary straight line of the cutting insert, the imaginary straight line of the cutting insert extending on the polygonal face on which the pair of contact surfaces are formed and being orthogonal to the insert central line,
and
of the side faces of the insert main body, on one of the side faces which faces one direction of two directions at which the imaginary straight line of the cutting insert of the pair of contact surfaces extends, there is formed a contact portion which is allowed to be in contact with a contacted portion formed on one wall face rising to the base of the insert seat.

2. The cutting insert according to claim 1 , wherein
the insert main body is formed in the shape of 180° rotationally symmetrical with respect to the insert central line orthogonal to the imaginary straight lines of the cutting insert of the pair of polygonal faces, and
on one of the other side faces for the polygonal face which faces the other direction of two directions at which the imaginary straight line of the cutting insert extends, there is formed the other contact portion which is allowed to be in contact with the contacted portion when the insert main body is rotated 180° around the insert central line.

3. The cutting insert according to claim 2 , wherein
each of the polygonal faces of the insert main body is formed in a quadrilateral shape,
the insert main body is provided with a pair of long side faces which are arranged so as to face to each other and a pair of short side faces which are arranged so as to face to each other,
a major cutting edge is formed at the side ridge portion of each of the polygonal faces, the side ridge portion being a portion intersecting each of the polygonal faces and each of the long side faces, and
the imaginary straight line of the cutting insert extends in a direction intersecting with each of the long side faces when the polygonal face is viewed from the front thereof, and the contact portion is formed on the long side face.

4. The cutting insert according to claim 3 , wherein
the major cutting edge formed at the side ridge portion of the polygonal face gradually inclines toward a second corner portion of the polygonal face from a first corner portion thereof and gradually inclines toward the opposite side of the polygonal face with respect to a direction of the insert central line, when the long side face is viewed from the front thereof.

5. The cutting insert according to claim 3 , wherein
the polygonal face of the insert main body is formed in the shape of a parallelogram having a pair of obtuse angle corner portions and a pair of acute angle corner portions,
a corner edge continuing to the major cutting edge is formed at the acute angle corner portion of each of the polygonal faces,
a minor cutting edge continuing to the corner edge is formed at the acute angle corner portion of the side ridge portion of each of the polygonal faces, the side ridge portion being a portion intersecting each of the polygonal faces and each of the short side faces, and
the imaginary straight line of the cutting insert extends in a direction orthogonal to the long side face when the polygonal face is viewed from the front thereof.

6. The cutting insert according to claim 5 , wherein
the major cutting edge formed at the side ridge portion of the polygonal faces gradually inclines toward the obtuse angle corner portion of the polygonal face which is formed like a parallelogram from the acute angle corner portion thereof and gradually inclines toward the opposite side of the polygonal face with respect to a direction of the insert central line, when the long side face is viewed from the front thereof.

7. The cutting insert according to claim 1 , wherein
the pair of contact surfaces are formed inside the polygonal face, and are inwardly spaced from the side ridge portion.

8. The cutting insert according to claim 1 , wherein
each of the pair of contact surfaces is provided with a plurality of contact surface portions which are arranged along the pair of imaginary flat faces of the cutting insert and spaced away from each other.

9. The cutting insert according to claim 1 , wherein
each of the pair of contact surfaces continues along the pair of imaginary flat faces of the cutting insert.

10. An indexable insert-type cutting tool which is provided with a tool main body rotated around an axis line and the cutting inserts according to claim 1 which is attached in a detachable manner to an outer circumference of the tool main body,
wherein one or more of the insert seats are formed on the tool main body in such a manner that the base faces in the tool rotating direction and one wall face rises to the base facing in the tool rotating direction;
each of the pair of contacted surfaces in contact with each of the pair of contact surfaces on the polygonal face which is used as the seating face of the cutting insert is formed on the base of the insert seat along a pair of imaginary flat faces of the insert seat;
each of the pair of imaginary flat faces of the insert seat includes one imaginary straight line of the insert seat extending over the base to intersect with the one wall face and, when the one wall face is viewed from the front thereof along the imaginary straight line of the insert seat, each of the pair of imaginary flat faces of the insert seat is arranged in a direction intersecting with each other in an X letter shape complementary to an X letter shape, which is formed by the pair of imaginary flat faces of the cutting insert of the polygonal face used as the seating face when seen in a direction along the imaginary straight line of the cutting insert; and
on the one wall face of the insert seat, there is formed a contacted portion which is in contact with a contact portion of the cutting insert.

11. The cutting insert according to claim 1 , wherein
the imaginary straight line of the cutting insert intersects with the side face on which the contact portion is formed.

12. The cutting insert according to claim 1 , wherein
the side face on

Assignees

• Mitsubishi Materials Corp

Inventors

• Horiike Nobukazu
• Takagi Yuji

Classifications

• B23C5/22

  Securing arrangements for bits or teeth {or cutting inserts} · CPC title

• B23C2210/50

  Cutting inserts · CPC title

• B23C5/202 Primary

  Plate-like cutting inserts with special form (special form related to securing of the insert B23C5/22) · CPC title

• B23C5/109 Primary

  with removable cutting inserts · CPC title

• B23C2200/0416

  Irregular · CPC title