Backing support for workpiece in chuck of machine tool

摘要

The support comprises a lower part supported on a machine tool frame and a height-adjustable upper part. A threaded spindle (20) interacts with a shackle (22a) connected to the upper part. An axially fixed rotatable threaded bush (50a), fitted with an inner thread interacting with the threaded spindle (20), is fitted in the shackle and can be moved by a handle. This movement is between a first position (I) fixed by a boundary and agreeing with the set height (H) of the backing support, and a second position (II) corresponding to the height of the upper part (12) lowered by a measure ( DELTA h). The threaded bush is axially fixed by a collar (51) and the handle fixed on the bush. The boundary in the first position can be produced by a fixed stop. A fixed stop can also be used to fix the second position. The stops may be formed by the walls of the lower part and where applicable by an extension of it.