Indexable construction unit for machine tools

摘要

In an indexable construction unit (1) for machine tools, with a first stationary table part (11) and a second drivable table part (21), a drive motor (31) with gearing (35) connected on the output side, a coupling member (41), an annular control member (51) and a locking mechanism (61) consisting of two pawls (62, 63), each of the pawls (62, 63) is provided with two symmetrically arranged inclined-contact surfaces (66, 67) which interact with mating surfaces (57, 58) made on one of the output gears (40) of the gearing (35) and on the same side with in each case a locking projection (70, 71). The locking projections (70, 71) are arranged in opposition to one another and for alternate locking of the control member (51) with the coupling member (41) can be inserted into the recesses (52) of the control member (51) which are allocated to the indexing positions of the construction unit (1). This configuration enables the locking of the control member (51) with the coupling member (41) to be released not by the force of springs but by the torque of the drive motor (31) so that reliable uncoupling is ensured. <IMAGE>