Hydraulic expanding chuck

Patent metadata

Field	Value
Publication number	US-11738394-B2
Application number	US-202117181032-A
Country	US
Kind code	B2
Filing date	Feb 22, 2021
Priority date	Aug 22, 2018
Publication date	Aug 29, 2023
Grant date	Aug 29, 2023

Abstract

A hydraulic expanding chuck for receiving and clamping a tool with a shank. The hydraulic expanding chuck has a main body, which on an axial side has a clamping section that extends along a longitudinal central axis of the expanding chuck and has a clamping part lying in a neck region and in which are formed a central receiving opening for receiving a tool shank and a chamber system to which a fluid pressure can be applied. The chamber system comprises at least one pressure chamber, which is separated from the receiving opening in the radial direction by an expansion wall yielding elastically under the fluid pressure, and which can be supplied with fluid pressure by means of at least one axial pressure channel running from a piston clamping mechanism accommodated in a clamping region of the hydraulic expanding chuck.

First claim

The invention claimed is:

1. A hydraulic expanding chuck for receiving and clamping a tool shank, comprising:
a main body;
a clamping section that extends along a longitudinal central axis of the expanding chuck, the clamping section having a clamping part lying in a neck region, in which are formed a central receiving opening for receiving the tool shank and a chamber system that can be supplied with a fluid pressure, the chamber system comprising at least a first pressure chamber, which in a radial direction is separated from the receiving opening by an expansion wall yielding elastically under the fluid pressure and which can be supplied with the fluid pressure via at least a first axial pressure channel, which proceeds axially from a piston clamping mechanism accommodated in a clamping region of the hydraulic expanding chuck, the first axial pressure channel being spaced radially from the longitudinal central axis by a first distance that is farther than a distance that the first pressure chamber is spaced radially from the longitudinal central axis, wherein, at least in the region that accommodates the piston clamping mechanism, the clamping section is configured and/or machined in such a way that recesses and cavities lying in the region that accommodates the piston clamping mechanism are positioned relative to each other and/or distributed over the circumference so that deformations and/or distortions induced by a pressure buildup while clamping the tool become superposed in the clamping region in such a way that the longitudinal central axis of the neck region remains largely in alignment with the longitudinal central axis of the expanding chuck.

2. The hydraulic expanding chuck according to claim 1 , wherein, at least in the region that accommodates the piston clamping mechanism, the clamping section is configured and/or machined in such a way that the cross section perpendicular to the longitudinal central axis has essentially an n-count rotational symmetry, wherein n is a whole number ≥2, and the cavities filled with hydraulic fluid are uniformly distributed over the circumference.

3. The hydraulic expanding chuck according to claim 1 , wherein, in the region that accommodates the piston clamping mechanism, the clamping region is configured and/or machined in such a way that the cross section perpendicular to the longitudinal central axis has essentially a point symmetry.

4. The hydraulic expanding chuck according to claim 3 , wherein, at least in the region that accommodates the piston clamping mechanism, the clamping section is configured and/or machined in such a way that the cross section perpendicular to the longitudinal central axis has essentially an n-count rotational symmetry, and n=2.

5. The hydraulic expanding chuck according to claim 1 , wherein the piston clamping mechanism has at least one bore for a sealed reception of a pressure piston that borders a pressure generating chamber and can be axially displaced by an allocated adjusting screw for building up a clamping pressure.

6. The hydraulic expanding chuck according to claim 5 , wherein the pressure generating chamber is hooked up to at least one filling and venting bore that can be sealed fluid tight.

7. The hydraulic expanding chuck according to claim 6 , wherein the at least one filling and venting bore can be locked by at least one closing body, which can be pressed against a closure seat under the influence of the clamping pressure generated by the piston clamping mechanism.

8. The hydraulic expanding chuck according to claim 1 , wherein the piston clamping mechanism lies essentially in a clamping plane perpendicular to the longitudinal central axis.

9. The hydraulic expanding chuck according to claim 8 , wherein at least one filling and venting bore lies essentially in the clamping plane.

10. The hydraulic expanding chuck according to claim 1 , wherein the clamping region has a diameter that essentially corresponds to a multiple of a diameter of the neck region.

11. The hydraulic expanding chuck according to claim 10 , wherein the length of the neck region corresponds to a multiple of the diameter of the neck region.

12. The hydraulic expanding chuck according to claim 10 , wherein the length of the neck region corresponds to a multiple of at least three times the diameter of the neck region.

13. The hydraulic expanding chuck according to claim 1 , wherein a shank part for coupling the hydraulic expanding chuck to a module of a modular tool system or to a machine spindle is fastened to the main body on a side facing away from the clamping region.

Assignees

• Guehring Kg

Inventors

• Kleiner Gilbert

Classifications

• B23B31/305 Primary

  the gripping means is a deformable sleeve · CPC title

• B23B31/302

  Hydraulic equipment, e.g. pistons, valves, rotary joints · CPC title