Tool holder assembly and method of manufacturing a tool holder

1. A tool holder for holding a tool for machining workpieces, the tool holder comprising:

a tool holder body defining a tool holder longitudinal axis;

a tool mount formed on the tool holder body and configured to secure a tool; and

a tool holder interface formed on the tool holder body and configured to fixate the tool holder to a holder shaft configured to be clamped in a machine tool, wherein the tool holder interface comprises:

a tool holder plane surface oriented transversely to the tool holder longitudinal axis and configured to come into abutment against a holder shaft plane surface provided at the holder shaft to establish a defined relative position in a longitudinal direction between the tool mount and the holder shaft,

a tool holder cone section having a polygonal cross-section and configured to come into engagement with a correspondingly polygonal holder shaft cone section in order to establish a defined relative position in a tangential direction between the tool mount and the holder shaft, and

a tool holder cylinder section configured to act together with a corresponding holder shaft cylinder section, wherein the tool holder cylinder section comprises only one radial recess comprising a slanted surface oriented at an angle and configured to interact with a longitudinal clamping screw of the holder shaft to axially tighten the tool holder cylinder section with the holder shaft cylinder section.

2. The tool holder of claim 1 , wherein the tool mount is arranged offset in a transverse direction with respect to the tool holder longitudinal axis, the radial recess being arranged on a side of the tool holder longitudinal axis opposite the tool mount as viewed in the transverse direction.

3. The tool holder of claim 1 , wherein the tool holder cone section has a substantially polygonal shape at least in a cross-section adjacent to the tool holder plane surface.

4. The tool holder of claim 1 , wherein a tool holder bore for supplying a coolant or lubricant is formed in the tool holder body.

5. A tool assembly comprising:

the tool holder of claim 1 ;

the tool secured to the tool holder; and

the holder shaft.

6. A method for manufacturing a tool holder for holding a tool for machining workpieces, the method comprising:

providing a tool holder blank;

forming a tool holder interface on the tool holder blank, wherein the tool holder interface is configured to fixate the tool holder to a holder shaft configured to be clamped in a machine tool, wherein the tool holder interface comprises:

a tool holder plane surface oriented transversely to a tool holder longitudinal axis and configured to come into abutment against a holder shaft plane surface provided at the holder shaft to establish a defined relative position in a longitudinal direction between a tool mount of the tool holder blank and the holder shaft,

a tool holder cone section having a polygonal cross-section and configured to come into engagement with a correspondingly polygonal holder shaft cone section in order to establish a defined relative position in a tangential direction between the tool mount and the holder shaft, and

a tool holder cylinder section configured to act together with a corresponding holder shaft cylinder section, wherein the tool holder cylinder section comprises a radial recess comprising a slanted surface oriented at an angle and configured to interact with a longitudinal clamping screw of the holder shaft to axially tighten the tool holder cylinder section with the holder shaft cylinder section;

inserting the tool holder blank into a reference holder shaft such that the tool holder plane surface abuts a holder shaft plane surface of the reference holder shaft; and

machining the tool mount to finish the tool holder, wherein the tool mount is configured to secure the tool.

7. The method of claim 6 , further comprising storing for the finished tool holder a reference length representing a dimension between the tool holder plane surface and a reference point of the tool mount.

8. A holder shaft for a tool holder, the holder shaft comprising:

a holder shaft body comprising a shaft section configured to be clamped in a clamping device of a machine tool, and further comprising a holder shaft interface for fastening a tool holder to the holder shaft body, wherein the holder shaft interface comprises:

a holder shaft plane surface oriented transversely to a tool holder longitudinal axis and configured to come into abutment against a tool holder plane surface provided at the tool holder in order to establish a defined relative position in a longitudinal direction between the tool holder and the holder shaft;

a holder shaft cone section having a polygonal cross-section and configured to come into engagement with a correspondingly polygonal tool holder cone section in order to establish a defined relative position in tangential direction between the tool holder and the holder shaft; and

a holder shaft cylinder section configured to act together with a corresponding tool holder cylinder section, wherein the holder shaft cylinder section comprises:

a radial threaded bore configured to receive a longitudinal clamping screw to engage in a radial recess of the tool holder to axially tighten the tool holder cylinder section with the holder shaft cylinder section, and

a radial clearance recess that:

extends over an axial length which is smaller than an axial length of the holder shaft cylinder section,

extends over an angular range of less than 360°, and

overlaps with the radial threaded bore in a circumferential direction.

9. The holder shaft of claim 8 , wherein the radial clearance recess extends over an angular range of less than 180°.

10. The holder shaft of claim 9 , wherein the radial clearance recess extends over an angular range of less than 150°.

11. The holder shaft of claim 8 , wherein the holder shaft body comprises a holder shaft bore for supplying a coolant or lubricant, wherein the holder shaft bore is configured to be connected to a tool holder bore of the tool holder.

12. The holder shaft of claim 11 , wherein the holder shaft bore opens into an end face of the holder shaft body opposite the holder shaft interface and comprises a sealing device configured to seal a feed tube introduced into the holder shaft bore.

13. A tool assembly comprising:

the holder shaft of claim 8 ;

the tool holder; and

a tool secured to the tool holder.

14. A holder shaft for a tool holder, the holder shaft comprising:

a holder shaft body comprising a shaft section configured to be clamped in a clamping device of a machine tool, and further comprising a holder shaft interface for fastening a tool holder to the holder shaft body, wherein the holder shaft interface comprises:

a holder shaft plane surface oriented transversely to a tool holder longitudinal axis and configured to come into abutment against a tool holder plane surface provided at the tool holder in order to establish a defined relative position in a longitudinal direction between the tool holder and the holder shaft;

a holder shaft cone section having a polygonal cross-section and configured to come into engagement with a correspondingly polygonal tool holder cone section in order to establish a defined relative position in tangential direction between the tool holder and the holder shaft; and

a holder shaft cylinder section configured to act together with a corresponding tool holder cylinder section, wherein the holder shaft cylinder section comprises:

a radial threaded bore configured to receive a longitudinal clamping screw to engage in a radial recess of the tool holder to axially tighten the tool holder cylinder section with the holder shaft cylinder section, and

a radial clearance recess that has, in a cross-section perpendicular to the holder shaft plane, the shape of a sickle.

15. The holder shaft of claim 14 , wherein the radial clearance recess extends over an angular range of less than 180°.

16. The holder shaft of claim 15 , wherein the radial clearance recess extends over an angular range of less than 150°.