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US-12623293-B2 - Tool holder having a cylindrical fixation bore extending rearwardly from a front fixation surface and a fastening bore intersecting the front fixation surface

US12623293B2US 12623293 B2US12623293 B2US 12623293B2US-12623293-B2

Abstract

A tool holder has a holder body, a first clamping member, and a first fastening member. The holder body includes a fixation portion and a mounting portion located rearward of the fixation portion. The fixation portion has a front fixation surface facing in a forward direction, a cylindrical fixation bore opening out to the front fixation surface and extending rearwardly therefrom, and a longitudinally extending primary slot connecting the fixation bore to a fixation envelope surface. The first clamping member occupies a first clamping bore and traverses the primary slot. The first fastening member occupies a first fastening bore which intersects the first clamping bore and opens out to the front fixation surface. The fixation bore has a fixation bore first primary diameter which decreases and increases when the first fastening member is rotated in first fastening and first unfastening directions about the first fastening member axis, respectively.

Inventors

  • HERBERT VOLK
  • PATRICK SCHÖFFEL

Assignees

  • ISCAR, LTD.

Dates

Publication Date
20260512
Application Date
20230418

Claims (20)

  1. 1 . A tool holder ( 20 ) having a longitudinal axis (AL) defining a forward direction (DF) and a rear direction (DR) opposite to the forward direction (DF), the tool holder ( 20 ) comprising: a holder body ( 22 ), a first clamping member ( 24 ), a first fastening member ( 26 ), the holder body ( 22 ) having a fixation portion ( 28 ) and a mounting portion ( 30 ) located rearward of the fixation portion ( 28 ), the fixation portion ( 28 ) having a front fixation surface ( 32 ) facing in the forward direction (DF) and defining a frontmost surface of the fixation portion ( 28 ), a cylindrical fixation bore ( 34 ) intersecting the front fixation surface ( 32 ) and extending rearwardly therefrom along the longitudinal axis (AL), a fixation envelope surface ( 36 ) extending rearwardly from the front fixation surface ( 32 ), and a longitudinally extending primary slot ( 38 ) connecting the fixation bore ( 34 ) to the fixation envelope surface ( 36 ) and intersecting the front fixation surface ( 32 ), the first clamping member ( 24 ) having a first clamping shaft ( 44 ) extending along a first clamping shaft axis (ACS 1 ), the first clamping shaft ( 44 ) occupying a first clamping bore ( 46 ) in the fixation portion ( 28 ) and traversing the primary slot ( 38 ), the first clamping bore ( 46 ) being non-threaded and passing through the fixation envelope surface ( 36 ) and extending on both sides of the primary slot ( 38 ), the first fastening member ( 26 ) extending along a first fastening member axis (AFM 1 ) and occupying a first fastening bore ( 48 ) in the fixation portion ( 28 ), the first fastening bore ( 48 ) intersecting the first clamping bore ( 46 ), extending along the longitudinal axis (AL), and opening out to the front fixation surface ( 32 ), the first fastening bore ( 48 ) being threaded, and the fixation portion ( 28 ) further comprising a resiliently displaceable fixation jaw ( 40 ) and a static base jaw ( 42 ) spaced apart by the primary slot, wherein in a cross-section taken in a first fixation plane (PF 1 ) perpendicular to the longitudinal axis (AL) and intersecting the primary slot ( 38 ), the fixation bore ( 34 ) has a fixation bore first primary diameter (DFB 1 ′) measured parallel to the first clamping shaft axis (ACS 1 ), and wherein: rotation of the first fastening member ( 26 ) in a first fastening direction (FD 1 ) about the first fastening member axis (AFM 1 ) causes the first fastening member ( 26 ) to operatively engage a first abutment surface ( 52 ) of the first clamping shaft ( 44 ) and the fixation bore first primary diameter (DFB 1 ′) to decrease, subsequent rotation of the first fastening member ( 26 ) in a first unfastening direction (UD 1 ) opposite to the first fastening direction (FD 1 ) about the first fastening member axis (AFM 1 ) causes the first fastening member ( 26 ) to operatively disengage from the first abutment surface ( 52 ) of the first clamping shaft ( 44 ) and the fixation bore first primary diameter (DFB 1 ′) to increase, the fixation jaw ( 40 ) is spaced apart from the mounting portion ( 30 ) by a secondary slot ( 64 ) transverse to the primary slot ( 38 ), the base jaw ( 42 ) merges with the mounting portion ( 30 ), and the secondary slot ( 64 ) communicates with the primary slot ( 38 ).
  2. 2 . The tool holder ( 20 ) according to claim 1 , wherein: the first fastening member axis (AFM 1 ) is parallel to the longitudinal axis (AL).
  3. 3 . The tool holder ( 20 ) according to claim 1 , wherein: the first clamping shaft axis (ACS 1 ) is contained in the first fixation plane (PF 1 ).
  4. 4 . The tool holder ( 20 ) according to claim 1 , wherein: the fixation jaw ( 40 ) is resiliently displaceable about a resilient axis of rotation (AR) extending parallel to the longitudinal axis (AL).
  5. 5 . The tool holder ( 20 ) according to claim 4 , wherein in the cross-section taken in the first fixation plane (PF 1 ): the resilient axis of rotation (AR) is located at a minimum fixation wall thickness (TWMIN) between the fixation envelope surface ( 36 ) and the fixation bore ( 34 ).
  6. 6 . The tool holder ( 20 ) according to claim 1 , wherein: in the cross-section taken in the first fixation plane (PF 1 ), the fixation bore ( 34 ) has a fixation bore first secondary diameter (DFB 1 ″) measured at a first fixation first rotational offset angle (α 1 ) of forty-five degrees from the fixation bore first primary diameter (DFB 1 ′), and wherein: rotation of the first fastening member ( 26 ) in the first fastening direction (FD 1 ) about the first fastening member axis (AFM 1 ) causes the fixation bore first secondary diameter (DFB 1 ″) to decrease, and subsequent rotation of the first fastening member ( 26 ) in the first unfastening direction (UD 1 ) about the first fastening member axis (AFM 1 ) causes the fixation bore first secondary diameter (DFB 1 ″) to increase.
  7. 7 . The tool holder ( 20 ) according to claim 1 , wherein: in a front view of the holder body ( 22 ), an imaginary first circle (C 1 ) having a first diameter (D 1 ) circumscribes the fixation portion ( 28 ), and the fixation bore first primary diameter (DFB 1 ′) is greater than thirty percent of the first diameter (D 1 ).
  8. 8 . The tool holder ( 20 ) according to claim 1 , wherein the fixation bore ( 34 ) is a through bore extending the entire longitudinal extent of the holder body ( 22 ).
  9. 9 . The tool holder ( 20 ) according to claim 1 , wherein: the first fastening member ( 26 ) has first and second fastening ends ( 70 , 72 ) and a threaded fastening portion ( 74 ) extending along the first fastening member axis (AFM 1 ) between the first and second fastening ends ( 70 , 72 ).
  10. 10 . The tool holder ( 20 ) according to claim 9 , wherein: the first fastening end ( 70 ) has a recessed or protruding torque transfer geometry, accessible from a location forward of the front fixation surface ( 32 ).
  11. 11 . The tool holder ( 20 ) according to claim 1 , further comprising a second clamping member ( 76 ) and a second fastening member ( 78 ), the second clamping member ( 76 ) having a second clamping shaft ( 80 ) extending along a second clamping shaft axis (ACS 2 ), the second clamping shaft ( 80 ) occupying a second clamping bore ( 82 ) in the fixation portion ( 28 ) and traversing the primary slot ( 38 ), and the second fastening member ( 78 ) extending along a second fastening member axis (AFM 2 ) and occupying a second fastening bore ( 84 ) in the fixation portion ( 28 ), wherein in a cross-section taken in a second fixation plane (PF 2 ) perpendicular to the longitudinal axis (AL) and intersecting the primary slot ( 38 ), the fixation bore ( 34 ) has a fixation bore second primary diameter (DFB 2 ′) measured parallel to the second clamping shaft axis (ACS 2 ), wherein the second fastening bore ( 84 ) intersects the second clamping bore ( 82 ) and opens out to the front fixation surface ( 32 ), and wherein: rotation of the second fastening member ( 78 ) in a second fastening direction (FD 2 ) about the second fastening member axis (AFM 2 ) causes the second fastening member ( 78 ) to operatively engage a second abutment surface ( 86 ) of the second clamping shaft ( 80 ) and the fixation bore second primary diameter (DFB 2 ′) to decrease, and subsequent rotation of the second fastening member ( 78 ) in a second unfastening direction (UD 2 ) opposite to the second fastening direction (FD 2 ) about the second fastening member axis (AFM 2 ) causes the second fastening member ( 78 ) to operatively disengage from the second abutment surface ( 86 ) of the second clamping shaft ( 80 ) and the fixation bore second primary diameter (DFB 2 ′) to increase.
  12. 12 . The tool holder ( 20 ) according to claim 11 , wherein: the second fastening member axis (AFM 2 ) is parallel to the longitudinal axis (AL).
  13. 13 . The tool holder ( 20 ) according to claim 11 , wherein: the second clamping shaft axis (ACS 2 ) is contained in the second fixation plane (PF 2 ).
  14. 14 . The tool holder ( 20 ) according to claim 11 , wherein: the first and second clamping shaft axes (ACS 1 , ACS 2 ) are contained in a third longitudinal plane (PL 3 ) parallel to the longitudinal axis (AL).
  15. 15 . The tool holder ( 20 ) according to claim 14 , wherein: the first and second fastening member axes (AFM 1 , AFM 2 ) are contained in the third longitudinal plane (PL 3 ).
  16. 16 . The tool holder ( 20 ) according to claim 1 , wherein: the mounting portion ( 30 ) has front and rear mounting surfaces ( 92 , 94 ) facing in the forward and rearward directions (DF, DR), respectively, the mounting portion ( 30 ) includes first and second mounting bores ( 96 , 98 ) having first and second mounting bore axes (AMB 1 , AMB 2 ), respectively, and each of the first and second mounting bores ( 96 , 98 ) open out to the front and rear mounting surfaces ( 92 , 94 ).
  17. 17 . The tool holder ( 20 ) according to claim 16 , wherein: a fourth longitudinal plane (PL 4 ) contains the first and second mounting bore axes (AMB 1 , AMB 2 ) and the longitudinal axis (AL), and the first and second mounting bore axes (AMB 1 , AMB 2 ) are equidistant from the longitudinal axis (AL).
  18. 18 . The tool holder ( 20 ) according to claim 1 , further comprising a radially expandable sleeve ( 60 ) occupying the fixation bore ( 34 ).
  19. 19 . A tool holder body ( 22 ) having a longitudinal axis (AL) defining a forward direction (DF) and a rear direction (DR) opposite to the forward direction (DF), the tool holder body ( 22 ) comprising: a mounting portion ( 30 ); and a fixation portion ( 28 ) located forward of the mounting portion ( 30 ), the fixation portion comprising: a front fixation surface ( 32 ) facing in the forward direction (DF) and defining a frontmost surface of the fixation portion ( 28 ); a cylindrical fixation bore ( 34 ) intersecting the front fixation surface ( 32 ) and extending rearwardly therefrom along the longitudinal axis (AL), the cylindrical fixation bore ( 34 ) configured to receive a tool shank; a fixation envelope surface ( 36 ) extending rearwardly from the front fixation surface ( 32 ); a longitudinally extending primary slot ( 38 ) connecting the fixation bore ( 34 ) to the fixation envelope surface ( 36 ) and intersecting the front fixation surface ( 32 ); a non-threaded first clamping bore ( 46 ) passing though the fixation envelope surface ( 36 ) and extending on both sides of the primary slot ( 38 ); and a threaded first fastening bore ( 48 ) extending along the longitudinal axis (AL), intersecting the first clamping bore ( 46 ), and opening out to the front fixation surface ( 32 ), wherein: the fixation portion ( 28 ) has a resiliently displaceable fixation jaw ( 40 ) and a static base jaw ( 42 ); the fixation jaw ( 40 ) and the base jaw ( 42 ) are spaced apart by the primary slot ( 38 ); the fixation jaw ( 40 ) is spaced apart from the mounting portion ( 30 ) by a secondary slot ( 64 ) transverse to the primary slot ( 38 ); the base jaw ( 42 ) merges with the mounting portion ( 30 ); and: the secondary slot ( 64 ) communicates with the primary slot ( 38 ).
  20. 20 . The tool holder body ( 22 ) according to claim 19 , further comprising: a non-threaded second clamping bore ( 82 ), parallel to the non-threaded first clamping bore ( 46 ), and passing through the fixation envelope surface ( 36 ) and extending on both sides of the primary slot ( 38 ); and a threaded second fastening bore ( 84 ) extending along the longitudinal axis (AL), intersecting the second clamping bore ( 82 ) and opening out to the front fixation surface ( 32 ).

Description

RELATED APPLICATIONS Priority is claimed to U.S. Provisional Patent Application No. 63/342,200 filed May 16, 2022. The contents of the aforementioned application are incorporated by reference in their entirety. FIELD OF THE INVENTION The present invention relates to a tool holder, and a cutting tool comprising the tool holder and a tool shank, for use in metal cutting processes in general, and more specifically for turning and drilling operations in which the cutting tool is static. BACKGROUND OF THE INVENTION Within the field of tool holders used in turning and drilling operations in which the cutting tool is static, there are some examples of tool holders configured to clampingly receive cylindrical tool shanks. DE 8311045 U1 discloses a tool holder for cylindrical tool shanks, and in particular for boring bars, with a clamping head which is slotted to form mutually adjustable clamping jaws, and a bushing that can be received into the chuck of a machine tool. The clamping head has a cylindrical bore which together with the slot extends the entire length of the clamping head and the bushing. The clamping jaws are adjusted relative to one another by two screws which traverse the slot in the region of the clamping head. US 2009/202314 A1 discloses a holder for a boring tool, which is formed from a sleeve and has increased stability of holding a cutting element to improve processing accuracy of the boring tool and to prevent chipping of a cutting edge. In the sleeve of the holder, the bar-like cutting element is inserted in a center hole in the sleeve and is held clamped by clamp means. A slit is provided in that portion of the sleeve which is from the forward end of the sleeve to the longitudinal middle of the sleeve, and the slit lies in a region from the center hole of the sleeve to its outer peripheral surface. Further, the holder has a fastener for tightening the slit portion of the sleeve to change the inner diameter of the center hole. It is an object of the present invention to provide an improved tool holder. It is also an object of the present invention to provide an improved tool holder having a cylindrical fixation bore in its front end. It is a further object of the present invention to provide an improved tool holder having a fastening member easily accessible from its front end. It is yet a further object of the present invention to provide an improved tool holder having a compactly configured front end fixation portion. SUMMARY OF THE INVENTION In accordance with the present invention, there is provided a tool holder having a longitudinal axis defining a forward-to-rear direction, and comprising a holder body, a first clamping member, and a first fastening member, the holder body having a fixation portion and a mounting portion located rearward of the fixation portion, the fixation portion having a front fixation surface facing in the forward direction, a cylindrical fixation bore intersecting the front fixation surface and extending rearwardly therefrom along the longitudinal axis, a fixation envelope surface extending rearwardly from the front fixation surface, and a longitudinally extending primary slot connecting the fixation bore to the fixation envelope surface and intersecting the front fixation surface, the first clamping member having a first clamping shaft extending along a first clamping shaft axis, the first clamping shaft occupying a first clamping bore in the fixation portion and traversing the primary slot, andthe first fastening member extending along a first fastening member axis and occupying a first fastening bore in the fixation portion, the first fastening bore intersecting the first clamping bore and opening out to the front fixation surface, wherein in a cross-section taken in a first fixation plane perpendicular to the longitudinal axis and intersecting the primary slot, the fixation bore has a fixation bore first primary diameter measured parallel to the first clamping shaft axis or an axial projection thereof, andwherein:rotation of the first fastening member in a first fastening direction about the first fastening member axis causes the first fastening member to operatively engage a first abutment surface of the first clamping shaft and the fixation bore first primary diameter to decrease, andsubsequent rotation of the first fastening member in a first unfastening direction opposite to the first fastening direction about the first fastening member axis causes the first fastening member to operatively disengage from the first abutment surface of the first clamping shaft and the fixation bore first primary diameter to increase. BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding, the invention will now be described, by way of example only, with reference to the accompanying drawings in which: FIG. 1 is a first perspective view from the front of a tool holder in accordance with some embodiments of the present invention; FIG. 2 is a secon