| 摘要 |
The rotary drive device for the drive of the sleeve of an electrical discharge machining unit comprises an electric motor, reversible with regard to the direction of rotation, and a reduction gear unit allocated to the electric motor. This reduction gear unit has a pinion (41) and two gear wheels (33, 35) rotatably mounted relative to one another. Both the gear wheels (33, 35) mesh with the pinion (41). One of the gear wheels (35) is under the effect of a torsion preloading force. A first gear wheel (33) of the two gear wheels of the reduction gear unit is coupled to the sleeve (20, 21) in such a way as to be locked in terms of rotation, while the second gear wheel (35) is rotatable relative to the sleeve. Such a rotary drive device works with little effort in both directions of rotation absolutely free of play, any wear which may arise being automatically compensated for. <IMAGE> |
