| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a device, which can be constituted simply and at a low cost, enables the change of a rotational position without fluctuation and changes the rotational position of a shaft relatively to a driving pulley. SOLUTION: Two pressure chambers to each other in an adjustment device 3 are always connected to a pressure medium pump 19 through control conduit pipes 16 and 17 respectively. Control valves 26 and 27 are arranged in the control conduit pipes respectively, and bypass connection sections 24 and 25 which are communicated to a pressure medium tank 28 can be formed by the control valves 26 and 27. Through this constitution, effective hydraulic clamping states or a tension state can be obtained in all operation positions and even during adjustment by always loading pressure to a pressure chamber working in the opposite direction, as a result, overlapping causing the fluctuation of changes in a rotary position is sufficiently eliminated.</p> |
