Tool holder having a clamping member with a non-circular cross-section and method for clamping a cutting insert therein
A tool holder has a main body with a holder head extending away from a holder shank, the holder head having an insert receiving pocket at a forward end thereof, with a pocket support surface. A clamping member is retained in the holder head, the clamping member comprising a clamping shaft longitudinally extending along a shaft axis. A locking member operatively engages an abutment surface of the clamping shaft. The shaft axis does not intersect the pocket support surface, and the clamping shaft has a non-circular shape in a cross-section taken perpendicular to the shaft axis. The tool holder is configured to direct a clamping force towards, and clamp a cutting insert against, the pocket support surface.
1. A tool holder ( 22 ) comprising:
a main body ( 26 ) having a holder head ( 28 ) extending away from a holder shank ( 30 ), the holder head ( 28 ) having an insert receiving pocket ( 32 ) at a forward end ( 34 ) thereof, with a pocket support surface ( 36 );
a clamping member ( 44 ) retained in the holder head ( 28 ), the clamping member ( 44 ) comprising a clamping shaft ( 46 ) longitudinally extending along a shaft axis (A 1 ); and
a locking member ( 52 ) operatively engaging an abutment surface ( 54 ) of the clamping shaft ( 46 ),
wherein the tool holder ( 22 ) is configured to direct a clamping force (f) towards, and clamp a cutting insert ( 24 ) against, the pocket support surface ( 36 ),
wherein the shaft axis (A 1 ) does not intersect the pocket support surface ( 36 ),
wherein the clamping shaft ( 46 ) has a non-circular shape in a cross-section taken perpendicular to the shaft axis (A 1 );
wherein the non-circular shape of the clamping shaft ( 46 ) has a minimum shaft width (WS MIN ); and
the clamping member ( 44 ) is retained in the holder head ( 28 ) such that the minimum shaft width (WS MIN ) extends principally along a width direction (WH) of the holder head ( 28 ).
2. The tool holder ( 22 ) according to claim 1 , wherein the clamping shaft ( 46 ) has a non-circular shape in a cross-section taken perpendicular to the shaft axis (A 1 ) along the whole of its length.
3. The tool holder ( 22 ) according to claim 1 , wherein the clamping shaft ( 46 ) has identical profiles in two cross-sections taken perpendicular to the shaft axis (A 1 ) at opposing shaft ends ( 50 a , 50 b ) thereof.
4. The tool holder ( 22 ) according to claim 1 , wherein the clamping shaft ( 46 ) is oblong shaped in a cross-section taken perpendicular to the shaft axis (A 1 ).
5. The tool holder ( 22 ) according to claim 1 , wherein the clamping shaft ( 46 ) is non-rotatable about its shaft axis (A 1 ), including when the locking member ( 52 ) is removed from the tool holder ( 22 ).
6. The tool holder ( 22 ) according to claim 1 , wherein the clamping shaft ( 46 ) exhibits 180° rotational symmetry about the shaft axis (A 1 ).
7. The tool holder ( 22 ) according to claim 1 , wherein the locking member ( 52 ) operatively engages a single abutment surface ( 54 ) of the clamping shaft ( 46 ).
8. The tool holder ( 22 ) according to claim 1 , wherein the abutment surface ( 54 ) is not visible in each end-view of the clamping member ( 44 ) taken axially along the shaft axis (A 1 ).
9. The tool holder ( 22 ) according to claim 1 , wherein the abutment surface ( 54 ) intersects an outer peripheral surface ( 56 ) of the clamping shaft ( 46 ).
10. The tool holder ( 22 ) according to claim 1 , wherein the clamping member ( 44 ) does not make contact with the cutting insert ( 24 ).
11. The tool holder ( 22 ) according to claim 1 , wherein the clamping member ( 44 ) is non-threadingly retained in the holder head ( 28 ) and the locking member ( 52 ) is threadingly retained in the holder head ( 28 ).
12. The tool holder ( 22 ) according to claim 1 , wherein the clamping shaft ( 46 ) is slidably retained in a clamping bore ( 48 ) in the holder head ( 28 ).
13. The tool holder ( 22 ) according to claim 12 , wherein the clamping shaft ( 46 ) is slidable solely in a direction along its shaft axis (A 1 ).
14. The tool holder ( 22 ) according to claim 12 , wherein the clamping bore ( 48 ) extends along a clamping axis (A 2 ) coaxial with the shaft axis (A 1 ), and
wherein the clamping bore ( 48 ) has a non-circular shape corresponding to the shape of the clamping shaft ( 46 ) in a cross-section taken perpendicular to the clamping axis (A 2 ).
15. The tool holder ( 22 ) according to claim 1 , wherein the abutment surface ( 54 ) is entirely located on one side of a shaft plane (P 1 ) containing the shaft axis (A 1 ).
16. The tool holder ( 22 ) according to claim 15 , wherein the clamping shaft ( 46 ) exhibits mirror symmetry about the shaft plane (P 1 ).
17. The tool holder ( 22 ) according to claim 15 , wherein:
the locking member ( 52 ) occupies a locking bore ( 58 ) in the holder head ( 28 ), and
the locking member ( 52 ) is entirely located on one side of the shaft plane (P 1 ).
18. The tool holder ( 22 ) according to claim 17 , wherein:
the locking bore ( 58 ) has a locking axis (A 3 ) perpendicular to the shaft plane (P 1 ), and
the locking bore ( 58 ) intersects at least one of two opposing outer lateral surfaces ( 60 a , 60 b ) of the holder head ( 28 ).
19. The tool holder ( 22 ) according to claim 15 , wherein:
the abutment surface ( 54 ) forms a portion of a frusto-conical shaped shaft recess ( 62 ) extending along a recess axis (A 4 ), and
the recess axis (A 4 ) is perpendicular to the shaft plane (P 1 ).
20. The tool holder ( 22 ) according to claim 19 , wherein:
the clamping member ( 44 ) includes a clamping head ( 64 ) at one shaft end ( 50 b ) of the clamping shaft ( 46 ),
the shaft recess ( 62 ) has a recess plane (P 2 ) containing the recess axis (A 4 ) and perpendicular to the shaft axis (A 1 ), and
the clamping head ( 64 ) and the abutment surface ( 54 ) are located on opposite sides of the recess plane (P 2 ).
21. The tool holder ( 22 ) according to claim 20 , wherein the clamping head ( 64 ) does not exhibit 180° rotational symmetry about the shaft axis (A 1 ).
22. The tool holder ( 22 ) according to claim 20 , wherein the clamping head ( 64 ) has a head under surface ( 66 ) immediately adjacent the clamping shaft ( 46 ) facing towards the recess plane (P 2 ).
23. The tool holder ( 22 ) according to claim 22 , wherein:
the head under surface ( 66 ) is substantially planar and perpendicular to the shaft axis (A 1 ), and
the abutment surface ( 54 ) faces towards a head plane (P 3 ) containing the head under surface ( 66 ).
24. The tool holder ( 22 ) according to claim 19 , wherein:
the recess axis (A 4 ) intersects the shaft axis (A 1 ), and
the abutment surface ( 54 ) forms an external acute abutment angle (a) with the recess axis (A 4 ).
25. The tool holder ( 22 ) according to claim 24 , wherein the abutment angle (a) is less than 45° and greater than 20°.
26. The tool holder ( 22 ) according to claim 19 , wherein the clamping shaft ( 46 ) has a maximum shaft width (WS MAX ) in a direction perpendicular to the shaft axis (A 1 ) and the recess axis (A 4 ).
27. The tool holder ( 22 ) according to claim 19 , wherein:
the minimum shaft width (WS MIN ) extends in a direction along the recess axis (A 4 ) and the shaft recess ( 62 ) has a recess depth (D 1 ) in a direction along the recess axis (A 4 ), and
the recess depth (D 1 ) is greater than a third of the minimum shaft width (WS MIN ).
28. The tool holder ( 22 ) according to claim 1 , wherein:
the insert receiving pocket ( 32 ) includes a pocket clamping surface ( 68 ) opposing the pocket support surface ( 36 ), and
the pocket clamping surface ( 68 ) and the pocket support surface ( 36 ) are spaced apart by a clamping distance (D 2 ).
29. The tool holder ( 22 ) according to claim 28 , wherein:
the pocket clamping surface ( 68 ) is formed on an elongated clamping portion ( 78 ) of the holder head ( 28 ), and
a coolant duct ( 80 ) extends through the clamping portion ( 78 ) and opens out to a coolant outlet port ( 82 ) adjacent the pocket clamping surface ( 68 ).
30. The tool holder ( 22 ) according to claim 28 , wherein:
the locking member ( 52 ) has a central axis (A 5 ), and
the clamping distance (D 2 ) is decreased by rotation of the locking member ( 52 ) in one direction about its central axis (A 5 ) and increased by rotation of the locking member ( 52 ) in an opposite direction about its central axis (A 5 ).
31. The tool holder ( 22 ) according to claim 1 , wherein the locking member ( 52 ) is in the form of a locking screw ( 70 ) having a threaded section ( 72 ) and a non-threaded section ( 74 ).
32. The tool holder ( 22 ) according to claim 31 , wherein:
the non-threaded section ( 74 ) includes an abutting surface ( 76 ) having a generally frusto-conical shape, and
a portion of the abutting surface ( 76 ) contacts the abutment surface ( 54 ) of the clamping shaft ( 46 ).
33. A tool holder ( 22 ) assembly comprising:
a main body ( 26 ) having a holder head ( 28 ) extending away from a holder shank ( 30 ) in a forward direction (F), the holder head ( 28 ) having an insert receiving pocket ( 32 ) at a forward end ( 34 ) thereof, the insert receiving pocket ( 32 ) having a pocket support surface ( 36 ) and an opposing pocket clamping surface ( 68 );
a clamping bore ( 48 ) formed in the main body ( 26 ) and extending along a clamping axis (A 2 ), the clamping axis (A 2 ) not intersecting the pocket support surface ( 36 ) and the clamping bore ( 48 ) having a non-circular shape in a cross-section taken perpendicular to the clamping axis (A 2 );
a locking bore ( 58 ) formed in the main body ( 26 ) and intersecting the clamping bore ( 48 );
a clamping member ( 44 ) configured to be received in the clamping bore ( 48 ), the clamping member ( 44 ) having a clamping shaft ( 46 ) with an abutment surface ( 54 ); and
a locking member ( 52 ) configured to be received in the locking bore ( 58 ) and operatively engage the clamping shaft's abutment surface ( 54 ) when the clamping member ( 44 ) is received into the clamping bore ( 48 ), to thereby apply a clamping force (f) which urges the pocket clamping surface ( 68 ) towards the pocket support surface ( 36 ); wherein:
the non-circular shape of the clamping bore ( 48 ) has a minimum bore width (WB MIN ); and
the clamping bore ( 48 ) is formed such that the minimum bore width (WB MIN ) extends principally along a width direction (WH) of the holder head ( 28 ).
34. The tool holder ( 22 ) assembly according to claim 33 , wherein:
the clamping shaft ( 46 ) longitudinally extends along a shaft axis (A 1 ) coaxial with the clamping axis (A 2 ) when the clamping member ( 44 ) is received into the clamping bore ( 48 ), and
wherein the clamping shaft ( 46 ) has a non-circular shape corresponding to the shape of the clamping bore ( 48 ) in a cross-section taken perpendicular to the shaft axis (A 1 ).
35. The tool holder ( 22 ) assembly according to claim 33 , wherein, when the clamping member ( 44 ) is received into the clamping bore ( 48 ), the clamping member ( 44 ) is non-threadingly retained therein and the locking member ( 52 ) is threadingly retained in the locking bore ( 58 ).
36. The tool holder ( 22 ) assembly according to claim 33 , wherein the clamping bore ( 48 ) is oblong shaped in a cross-section taken perpendicular to the clamping axis (A 2 ).
37. The tool holder ( 22 ) assembly according to claim 33 , wherein:
the locking bore ( 58 ) has a locking axis (A 3 ) perpendicular to the clamping axis (A 2 ), and
the locking bore ( 58 ) intersects at least one of two opposing outer lateral surfaces ( 60 a , 60 b ) of the holder head ( 28 ).
38. The tool holder ( 22 ) assembly according to claim 37 , wherein the minimum bore width (WB MIN ) extends in a direction along the locking axis (A 3 ).
39. The tool holder ( 22 ) assembly according to claim 33 , wherein, when the clamping member ( 44 ) is received into the clamping bore ( 48 ), the clamping shaft ( 46 ) is non-rotatable about a longitudinally extending shaft axis (A 1 ) thereof, even when the locking member ( 52 ) is not engaged to the abutment surface ( 54 ) of the clamping shaft ( 46 ).
40. A cutting tool ( 20 ) comprising:
the tool holder ( 22 ) assembly according to claim 33 ; and
a cutting insert ( 24 ) clampingly retained in the insert receiving pocket ( 32 ) between the pocket support surface ( 36 ) and the pocket clamping surface ( 68 ).
41. A method of assembling a cutting tool ( 20 ) which comprises the tool holder ( 22 ) assembly of claim 33 and a cutting insert ( 24 ), the cutting insert ( 24 ) having opposing first and second insert surfaces ( 38 , 40 ) with an operative cutting edge ( 42 ) associated with the first insert surface ( 38 ), the method comprising the steps of:
positioning the cutting insert ( 24 ) adjacent the forward end ( 34 ) of the holder head ( 28 ) with a portion of the second insert surface ( 40 ) in contact with the pocket support surface ( 36 ),
sliding the cutting insert ( 24 ) in a generally rearward direction (R) into the insert receiving pocket ( 32 ), and
actuating the locking member ( 52 ) until a clamping force (f) is applied between the second insert surface ( 40 ) and the pocket support surface ( 36 ).
42. A tool holder ( 22 ) assembly comprising:
a main body ( 26 ) having a holder head ( 28 ) extending away from a holder shank ( 30 ), the holder head ( 28 ) having an insert receiving pocket ( 32 ) at a forward end ( 34 ) thereof, with a pocket support surface ( 36 );
a clamping bore ( 48 ) formed in the main body ( 26 ) and extending along a clamping axis (A 2 ), the clamping axis (A 2 ) not intersecting the pocket support surface ( 36 );
a locking bore ( 58 ) formed in the main body ( 26 ) and intersecting the clamping bore ( 48 );
a clamping member ( 44 ) configured to be received in the clamping bore ( 48 ), the clamping member ( 44 ) having a clamping shaft ( 46 ) longitudinally extending along a shaft axis (A 1 ); and
a locking member ( 52 ) configured to be received in the locking bore ( 58 ) and operatively engage an abutment surface ( 54 ) of the clamping shaft ( 46 ) when the clamping member ( 44 ) is received into the clamping bore ( 48 );
wherein, when the clamping member ( 44 ) is received into the clamping bore ( 48 ), the clamping shaft ( 46 ) is non-rotatable about the shaft axis (A 1 ), even when the locking member ( 52 ) is not engaged to the abutment surface ( 54 ) of the clamping shaft ( 46 ); and wherein:
the clamping bore ( 48 ) has a minimum bore width (WB MIN );
the clamping shaft ( 46 ) has a minimum shaft width (WS MIN ); and
the minimum bore width (WB MIN ) and the minimum shaft width (WS MIN ) both extend principally along a width direction (WH) of the holder head ( 28 ).