WORKING SPINDLE WITH RADIAL CLAMPING DEVICE

• US 20200130117A1
• Filed: 06/15/2018
• Published: 04/30/2020
• Est. Priority Date: 06/19/2017
• Status: Active Grant

• Current Assignee: GEBR Heller Maschinenfabrik GmbH (Heller GmbH)
• Original Assignee: GEBR Heller Maschinenfabrik GmbH (Heller GmbH)
• Inventors: Dorn, Thomas, WALZ, Jurgen
• Granted Patent: US 11,135,691 B2
• Time in Patent Office: Days
• CPC Class Codes: B23B 3/065 Arrangements for performing other machining operations, e.g. milling, drilling
• CPC Class Codes: B23Q 1/287 using a hydraulically controlled membrane acting directly upon a sliding member
• CPC Class Codes: B23Q 1/70 Stationary or movable members for carrying working-spindles for attachment of tools or work B23Q1/01 takes precedence; designed to be moved by using particular mechanisms B23Q1/44
• CPC Class Codes: B23Q 2705/026 Main drive for the spindles of milling machines
• CPC Class Codes: B23Q 3/12 for securing to a spindle in general B23Q3/152 takes precedence; chucks B23B31/02
• CPC Class Codes: B23Q 5/04 rotary shafts, e.g. working-spindles
• CPC Class Codes: B23Q 5/20 Adjusting or stopping working-spindles in a predetermined position
• CPC Class Codes: Y10T 29/5112 Convertible
• CPC Class Codes: Y10T 409/309352 Cutter spindle or spindle support

Abstract

The inventive working spindle comprises a spindle housing and a spindle shaft with axial positioning surface and axial contact surface by which the correct axial position of each fitting provided spindle shaft in the spindle housing is obtained. For torque-proof holding of the spindle shaft in the spindle housing, preferably with stationary motor, a braking unit is provided that comprises a radial outer part that is coupled with the spindle housing in a torque-proof manner and a radial inner part that is coupled with the spindle shaft in a torque-proof manner. The largest outer diameter of the peripheral surface of the inner part is smaller than the narrowest location of the through-opening of the spindle housing between the braking unit and the tool side end of the spindle housing. For this reason the spindle shaft can be readily removed from the spindle housing without disassembly measures of the braking unit, if required, and can be reinserted in reverse route. The inventive working spindle is simply constructed and can be versatilely used. Concurrently it is remarkably easy to maintain.

Claims

1. A working spindle for a machine tool, the working spindle having:

a spindle housing having a through-opening;

a spindle shaft that is arranged in the through-opening of the spindle housing, the spindle shaft having a holding fixture for a tool or a tool holder at one end at one end of the spindle shaft and a coupling for a drive at another end of the spindle shaft;

at least two roller bearings that are arranged with an axial distance from each other on the spindle shaft, the at least two roller bearings being located in the spindle housing in order to rotatably support the spindle shaft in the spindle housing; and

a braking unit comprising a first part that is connected with a spindle shaft in a torque-proof manner and a second part that is connected with the spindle housing in a torque-proof manner, wherein the first part has a diameter that is smaller than an outer diameter of one of the at least two roller bearings.

2. The working spindle according to claim 1, wherein the at least two roller bearings have similar bearing outer diameters.

3. The working spindle according to claim 1, wherein the at least two roller bearings have different bearing outer diameters and the diameter of the first part is smaller than the bearing outer diameters of the at least two roller bearings.

4. The working spindle according to claim 1, wherein the first part that is connected with the spindle shaft comprises a cylindrical outer peripheral surface that defines the diameter of the first part.

5. The working spindle according to claim 1, wherein the second part comprises a friction surface that is radially movably arranged with respect to the first part.

6. The working spindle according to claim 5, wherein the second part is deformable in a radial direction in order to bring the friction surface and an outer peripheral surface of the first part into and out of engagement.

7. The working spindle according to claim 1, wherein the second part comprises a ring that is arranged such that a peripheral surface of the ring closes a hydraulic chamber radially inwardly.

8. The working spindle according to claim 1, wherein the first part and the second part of the braking unit are connected or connectable in a torque-proof manner.

9. The working spindle according to claim 1, wherein the spindle housing comprises an axial positioning surface for the spindle shaft.

10. The working spindle according to claim 9, wherein the spindle shaft comprises an axial contact surface that is in contact with the axial positioning surface in the assembled condition.

11. The working spindle according to claim 2, wherein the first part that is connected with the spindle shaft comprises a cylindrical outer peripheral surface that defines the diameter of the first part.

12. The working spindle according to claim 3, wherein the first part that is connected with the spindle shaft comprises a cylindrical outer peripheral surface that defines the diameter of the first part.

13. The working spindle according to claim 2, wherein the second part comprises a friction surface that is radially movably arranged with respect to the first part.

14. The working spindle according to claim 3, wherein the second part comprises a friction surface that is radially movably arranged with respect to the first part.

15. The working spindle according to claim 11, wherein the second part comprises a friction surface that is radially movably arranged with respect to the first part.

16. The working spindle according to claim 15, wherein the second part) is deformable in a radial direction in order to bring the friction surface and an outer peripheral surface of the first part into and out of engagement.

17. The working spindle according to claim 16, wherein the second part comprises a ring that is arranged such that a peripheral surface of the ring closes a hydraulic chamber radially inwardly.

18. The working spindle according to claim 17, wherein the first part and the second part of the braking unit are connected or connectable in a torque-proof manner.

19. The working spindle according to claim 18, wherein the spindle housing) comprises an axial positioning surface for the spindle shaft.

20. The working spindle according to claim 19, wherein the spindle shaft comprises an axial contact surface that is in contact with the axial positioning surface in the assembled condition.