| 摘要 |
An improved machine tool includes a hydraulically actuated coupling assembly. The coupling assembly includes a first coupling member which is fixedly connected with a turret a second coupling member which is connected with a drive assembly for moving the turret axially. When the coupling assembly is engaged, annular arrays of teeth on the coupling members are disposed in meshing engagement to hold the turret against rotation. When the coupling assembly is disengaged, the teeth are spaced apart and the turret can be rotated by a drive motor. When the coupling assembly is to be disengaged, a valve is actuated to port fluid under pressure to a first chamber formed between face surfaces on the two coupling members to move them apart and disengage the teeth. When the coupling assembly is to be re-engaged, the valve is actuated to port fluid under pressure to a second chamber to effect movement of the coupling members toward each other. During subsequent movement of the turret under the influence of the axial drive assembly, fluid pressure in the second chamber prevents disengagement of the coupling assembly. |
