Rotationally asymmetric cutting insert having a single radially extending cutting-edge portion and rotary cutting tool

Patent metadata

Field	Value
Publication number	US-11524344-B2
Application number	US-202016855639-A
Country	US
Kind code	B2
Filing date	Apr 22, 2020
Priority date	Apr 22, 2020
Publication date	Dec 13, 2022
Grant date	Dec 13, 2022

Abstract

A cutting insert rotatable about an axis, has opposing front and rear surfaces interconnected by an insert peripheral surface, the insert peripheral surface having first and second side surfaces spaced apart by first and second land surfaces. First and second land edges extend along the first and second land surfaces, respectively. A first front edge formed at the intersection of the front surface and the first side surface includes a cutting-edge portion, and a second front edge formed at the intersection of the front surface and the second side surface is devoid of a cutting-edge portion. A cutting profile formed by rotating the cutting-edge portion about the axis is located axially forward of the second front edge. The cutting insert is releasably secured to a tool shank, the cutting insert being located between two protuberances protruding from a forward end portion of the tool shank.

First claim

What is claimed is:

1. A rotationally asymmetric cutting insert ( 20 ) rotatable about an insert axis (AI) in a direction of cutting rotation (RC), the insert axis (AI) defining an insert forward-rearward direction (IF, IR), the cutting insert ( 20 ) comprising;
opposing front and rear surfaces ( 22 , 24 ) interconnected by an insert peripheral surface ( 26 ), the insert peripheral surface ( 26 ) having first and second side surfaces ( 28 , 30 ) spaced apart by first and second land surfaces ( 32 , 34 ),
a first land edge ( 36 ) formed at the intersection of the first side surface ( 28 ) and the first land surface ( 32 ) and extending rearwardly from a first end point (N 1 ) located on the front surface ( 22 ), along the first land surface ( 32 ),
a second land edge ( 38 ) formed at the intersection of the second side surface ( 30 ) and the second land surface ( 34 ) and extending rearwardly from the front surface ( 22 ) along the second land surface ( 34 );
a first front edge ( 46 ) formed at the intersection of the front surface ( 22 ) and the first side surface ( 28 ), the first front edge ( 46 ) including a cutting-edge portion ( 48 ) which extends radially outward to the first land edge ( 36 ); and
a second front edge ( 52 ) formed at the intersection of the front surface ( 22 ) and the second side surface ( 30 ), the second front edge ( 52 ) being devoid of a cutting-edge portion,
a first insert plane (PI 1 ) containing the insert axis (A 1 ) and the first end point (N 1 );
a second insert plane (PI 2 ) perpendicular to the first insert plane (PI 1 ) and also containing the insert axis (A 1 ), the second insert plane (PI 2 ) intersecting the first insert plane (PI 1 ) to thereby form first, second third and fourth imaginary quadrants (Q 1 , Q 2 , Q 3 , Q 4 );
wherein:
the first side surface ( 28 ) includes a rake surface ( 50 ) adjacent the cutting-edge portion ( 48 ), the rake surface ( 50 ) facing in the direction of cutting rotation (RC);
the first and second land edges ( 36 , 38 ) are contained in an envelope surface ( 40 ) of an imaginary first cylinder (C 1 ) having a circular cross-section and a cylinder axis (AC) coaxial with the insert axis (AI), the imaginary first cylinder (C 1 ) having a first diameter (D 1 ),
an imaginary cutting profile (PC) formed by rotating the cutting-edge portion ( 48 ) 360 degrees about the insert axis (AI) is located axially forward of the second front edge ( 52 ) and defines a cutting diameter (DC) which corresponds to the first diameter (D 1 ),
the second land surface ( 34 ) includes a first support surface ( 42 ) contained in the envelope surface ( 40 ) of the imaginary first cylinder (C 1 ), and
in a front view of the cutting insert ( 20 ), the first support surface ( 42 ) is entirely located in the first imaginary quadrant (Q 1 ).

2. The cutting insert ( 20 ) according to claim 1 , wherein the imaginary cutting profile (PC) is located axially forward of any edge associated with the front surface ( 22 ), apart from the cutting-edge portion ( 48 ).

3. The cutting insert ( 20 ) according to claim 1 , wherein the first land edge ( 36 ) is straight and parallel to the insert axis (AI).

4. The cutting insert ( 20 ) according to claim 1 , wherein the cutting-edge portion ( 48 ) extends radially outwardly from the insert axis (AI).

5. The cutting insert ( 20 ) according to claim 1 , wherein the entire cutting-edge portion ( 48 ) is contained in the first insert plane (PI 1 ).

6. The cutting insert ( 20 ) according to claim 1 , wherein:
a shoulder portion ( 54 ) protrudes from the second side surface ( 30 ), and
the shoulder portion ( 54 ) has a second support surface ( 56 ) contained in the envelope surface ( 40 ) of the imaginary first cylinder (C 1 ).

7. The cutting insert ( 20 ) according to claim 6 , wherein:
the second support surface ( 56 ) is entirely located in a second imaginary quadrant (Q 2 ) circumferentially adjacent to the first imaginary quadrant (Q 1 ) and separated therefrom by the second insert plane (PI 2 ).

8. The cutting insert ( 20 ) according to claim 7 , wherein:
the first land surface ( 32 ) includes a third support surface ( 58 ) contained in the envelope surface ( 40 ) of the imaginary first cylinder (C 1 ), and
the third support surface ( 58 ) is entirely located in the second imaginary quadrant (Q 2 ).

9. The cutting insert ( 20 ) according to claim 1 , wherein the cutting-edge portion ( 48 ) has an axially forwardmost cutting point (NF) located radially mid-way between the insert axis (AI) and the envelope surface ( 40 ) of the imaginary first cylinder (C 1 ).

10. The cutting insert ( 20 ) according to claim 1 , wherein an insert opening ( 84 ) extends from the first side surface ( 28 ) to the second side surface ( 30 ).

11. The cutting insert ( 20 ) according to claim 10 , wherein the insert opening ( 84 ) is asymmetrically located with respect to the insert axis (AI).

12. The cutting insert ( 20 ) according to claim 1 , wherein:
the first support surface ( 42 ) circumferentially extends from the second land edge ( 38 ) in a direction opposite to the direction of cutting rotation (RC).

13. A rotary cutting tool ( 64 ) comprising:
a tool shank ( 66 ) extending along a shank axis (AS) defining a shank forward-rearward direction (SF, SR), the tool shank ( 66 ) comprising circumferentially spaced apart first and second protuberances ( 68 , 70 ) protruding axially from a forward end portion ( 72 ) thereof and an insert receiving slot ( 74 ) located between the first and second protuberances ( 68 , 70 ); and
a rotationally asymmetric cutting insert ( 20 ) rotatable about an insert axis (AI) in a direction of cutting rotation (RC), the insert axis (AI) defining an insert forward-rearward direction (IF, IR), the cutting insert ( 20 ) comprising;
opposing front and rear surfaces ( 22 , 24 ) interconnected by an insert peripheral surface ( 26 ), the insert peripheral surface ( 26 ) having first and second side surfaces ( 28 , 30 ) spaced apart by first and second land surfaces ( 32 , 34 ),
a first land edge ( 36 ) extending rearwardly from the front surface ( 22 ) along the first land surface ( 32 ),
a second land edge ( 38 ) extending rearwardly from the front surface ( 22 ) along the second land surface ( 34 );
a first front edge ( 46 ) formed at the intersection of the front surface ( 22 ) and the first side surface ( 28 ), the first front edge ( 46 ) including a radially extending cutting-edge portion ( 48 ); and
a second front edge ( 52 ) formed at the intersection of the front surface ( 22 ) and the second side surface ( 30 ), the second front edge ( 52 ) being devoid of a cutting-edge portion,
wherein:
the first side surface ( 28 ) includes a rake surface ( 50 ) adjacent the cutting-edge portion ( 48 ), the rake surface ( 50 ) facing in the direction of cutting rotation (RC);
the first and second land edges ( 36 , 38 ) are contained in an envelope surface ( 40 ) of an imaginary first cylinder (C 1 ) having a circular cross-section and a cylinder axis (AC) coaxial with the insert axis (AI), the imaginary first cylinder (C 1 ) having a first diameter (D 1 ), and
an imaginary cutting profile (PC) formed by rotating the cutting-edge portion ( 48 ) 360 degrees about the insert axis (AI) is located axially forward of the second front edge ( 52 ) and defines a cutting diameter (DC) which corresponds to the first diameter (D 1 );

wherein:
the cutting insert ( 20 ) is releasably secured to the tool shank ( 66 ) in the insert receiving slot ( 74 );
the insert axis (AI) is coaxial with the shank axis (AS); and
the insert's front surface ( 22 ) faces i

Assignees

• Iscar Ltd

Inventors

• Hecht Gil

Classifications

• B23B2251/50

  Drilling tools comprising cutting inserts · CPC title

• B23B27/145 Primary

  characterised by having a special shape · CPC title

• B23B51/0493

  with exchangeable cutting inserts, e.g. able to be clamped · CPC title

• B23B51/00

  Tools for drilling machines · CPC title

• B23B2200/0457

  Pentagonal · CPC title