| 摘要 |
PURPOSE:To enlarge cushion possible range by providing a valve body on a piston in a rack-pinion rotation driving device, thereby blocking a main fluid path communicating with a feed and discharge port. CONSTITUTION:When pressurized fluid is supplied to a port 31a to discharge a fluid through a feed and discharge port 31, a valve body 8a is first pushed to the right to open a main fluid path 32a, so that pressurized fluid enters a piston chamber C2 to push pistons 4a, 4 to the right, thereby rotating a pinion 6 and a driving shaft 60 clockwise. At this time, though the fluid in a piston chamber C1 is at first discharged through a main fluid path 32 and a throttle path 33, a valve body 8 is brought into contact with the inner surface of an end cover 3 by movement of the piston to close the main fluid path 32. Accordingly, the fluid in the piston chamber C1 can be discharged only through the throttle path 33, so that the piston is subjected to cushion action corresponding to the opening of a variable throttle valve 34.
|
