Cutting tool assembly

Patent metadata

Field	Value
Publication number	US-9868157-B2
Application number	US-201314418165-A
Country	US
Kind code	B2
Filing date	Aug 6, 2013
Priority date	Aug 8, 2012
Publication date	Jan 16, 2018
Grant date	Jan 16, 2018

Abstract

A cutting tool assembly has a cutter body, a clamp pin, a cutting insert and a set screw. The clamp pin is inserted to the cutter body to secure the cutting insert to an insert pocket. The set screw is fastened to a threaded hole of the cutter body to press the clamp pin toward the insert pocket. A side surface of the cutting insert contacts a side wall of the insert pocket at a first contact portion. A head of the clamp pin contact an inner peripheral surface of a bore of the cutting insert at a second contact portion. The first and second contact portions are located such that a moment acts on the cutting insert toward the base wall of the insert pocket around the first contact portion.

First claim

The invention claimed is:

1. A cutting tool assembly, comprising:
a cutter body comprising:
an insert pocket having a base wall, two or more side walls and a corner portion between the side walls;
a clamp pin hole obliquely extending from the base wall; and
a threaded hole inclined with respect to the clamp pin hole and joined to a lower portion of the clamp pin hole at an inner end thereof;

a clamp pin comprising:
a pin body inserted to the clamp pin hole and having a body central axis (C 1 ) extending in a longitudinal direction;
a head extending along a head central axis (C 2 ) forming an angle (α) with the body central axis (C 1 ), the head having a pressing surface directed to the corner portion of the insert pocket; and
a notch formed at a lower portion of the pin body;

a cutting insert comprising:
a top surface;
a bottom surface;
side surfaces located between the top surface and the bottom surface and contacting the side walls of the insert pocket; and
a bore having an inner peripheral surface which the pressing surface of the head contacts;

a set screw fastened to the threaded hole, the set screw engaging the notch of the clamp pin and pressing the head of the clamp pin toward the base wall of the insert pocket, and
a spring disposed between a closed end of the clamp pin hole and a bottom end of the pin body; wherein:
a first contact portion (P 3 ) where the side surface of the cutting insert contacts the side wall of the insert pocket and a second contact portion (P 4 ) where the pressing surface of the head contacts the inner peripheral surface of the bore are located such that a moment acts on the cutting insert toward the base wall of the insert pocket around the first contact portion (P 3 ).

2. The cutting tool assembly of claim 1 , wherein a height of the first contact portion (P 3 ) from the base wall is higher than a height of the second contact portion (P 4 ) from the base wall.

3. The cutting tool assembly of claim 1 , wherein the head is twisted at an angle (γ) relative to the head central axis (C 2 ) to be directed to the corner portion.

4. The cutting tool assembly of claim 3 , wherein the angle (γ) ranges from 0 degree to 90 degrees.

5. The cutting tool assembly of claim 1 , wherein at least a portion of the side wall excluding the first contact surface (P 3 ) is spaced apart from the side surface at an angle (ε,ε′).

6. The cutting tool assembly of claim 5 , wherein the angle (ε) is 1 degree or less.

7. The cutting tool assembly of claim 1 , wherein the inner peripheral surface of the bore is inclined at an angle (δ) with respect to a bore central axis (C 3 ) of the bore.

8. The cutting tool assembly of claim 7 , wherein the angle (δ) ranges from 10 degrees to 60 degrees.

9. The cutting tool assembly of claim 8 , wherein the angle (δ) ranges from 15 degrees to 30 degrees.

10. The cutting tool assembly of claim 1 , wherein the angle (α) ranges from 30 degrees to 60 degrees.

11. The cutting tool assembly of claim 10 , wherein the angle (α) ranges from 40 degrees to 45 degrees.

12. The cutting tool assembly of claim 1 , wherein a contact angle (β) between the pressing surface of the head and the inner peripheral surface of the bore ranges from 60 degrees to 150 degrees.

13. The cutting tool assembly of claim 12 , wherein the pressing surface of the head contacts the inner peripheral surface of the bore within the contact angle (β) in part.

14. The cutting tool assembly of claim 1 , wherein the pin body comprises a positioning ridge protruding from the pin body opposite the notch, the positioning ridge extending in a longitudinal direction of the pin body.

15. A cutting tool assembly, comprising:
a cutter body comprising:
an insert pocket having a base wall, two or more side walls and a corner portion between the side walls;
a clamp pin hole obliquely extending from the base wall; and
a threaded hole inclined with respect to the clamp pin hole and joined to a lower portion of the clamp pin hole at an inner end thereof;

a clamp pin comprising:
a pin body inserted to the clamp pin hole and having a body central axis (C 1 ) extending in a longitudinal direction;
a head extending along a head central axis (C 2 ) forming an angle (α) with the body central axis (C 1 ), the head having a pressing surface directed to the corner portion of the insert pocket; and
a notch formed at a lower portion of the pin body;
wherein the pin body comprises a stopper protrusion protruding from the pin body, the stopper protrusion being rotationally opposite the notch, relative to the body central axis (C 1 ), such that an imaginary line (L 1 ) passing through the stopper protrusion and perpendicular to the body central axis (C 1 ) intersects the notch;

a cutting insert comprising:
a top surface;
a bottom surface;
side surfaces located between the top surface and the bottom surface and contacting the side walls of the insert pocket; and
a bore having an inner peripheral surface which the pressing surface of the head contacts; and

a set screw fastened to the threaded hole, the set screw engaging the notch of the clamp pin and pressing the head of the clamp pin toward the base wall of the insert pocket, wherein:
a first contact portion (P 3 ) where the side surface of the cutting insert contacts the side wall of the insert pocket and a second contact portion (P 4 ) where the pressing surface of the head contacts the inner peripheral surface of the bore are located such that a moment acts on the cutting insert toward the base wall of the insert pocket around the first contact portion (P 3 ).

16. The cutting tool assembly of claim 15 , wherein the stopper protrusion is above a valley of the notch in the longitudinal direction of the pin body.

17. The cutting tool assembly of claim 15 , wherein the clamp pin hole and the pin body have a cross section of an oval shape or a racetrack shape.

18. A clamp pin for clamping a cutting insert in a cutting tool, the clamp pin comprising:
a pin body having a body central axis (C 1 ) extending in a longitudinal direction;
a head extending along a head central axis (C 2 ) which forms an angle (α) with the body central axis (C 1 ), the angle (α) ranging from 30 degrees to 60 degrees;
a notch formed at a lower portion of the pin body;
a stopper protrusion formed at a lower portion of the pin body and being rotationally opposite the notch, relative to the body central axis (C 1 ), such that an imaginary line (L 1 ) passing through the stopper protrusion and perpendicular to the body central axis (C 1 ) intersects the notch; and
a pressing surface formed on the head;
wherein in a side view of the clamp pin in which the angle (α) appears greatest:
the notch faces in a first direction while the stopper protrusion and the pressing surface protrude in a second direction which is opposite the first direction; and
the body central axis (C 1 ) and the head central axis (C 2 ) form a supplementary angle ranging from 120 degrees to 90 degrees, the supplementary angle opening in the second direction.

19. A cutting tool assembly, comprising:
a cutter body comprising:
an insert pocket having a base wall, two or more side walls and a corner portion between the side walls;
a clamp pin hole obliquely extending from the base wall; and
a threaded hole inclined with respect to the clamp pin hole and joined to a lower portion of the clamp pin hole at an inner end thereof;

a clamp pin in accordance with claim 18 having the pin body inserted into to the clamp pin ho

Assignees

• Taegu Tec Ltd
• Taegu Tec Ltd

Inventors

• Choi Chang Hee
• Park Chang Gyu

Classifications

• B23C5/2208 Primary

  for plate-like cutting inserts  (B23C5/2226, B23C5/2234 take precedence) · CPC title

• B23B2205/04

  Fixation screws, bolts or pins of particular form · CPC title

• B23C2210/165

  Fixation bolts · CPC title

• B23B27/1662 Primary

  with plate-like cutting inserts clamped against the walls of the recess in the shank by a clamping member acting upon the wall of a hole in the cutting insert (B23B27/1677 takes precedence) · CPC title

• Y10T407/28

  Miscellaneous · CPC title