| 摘要 |
<p>In a tubular member, a hydraulic pressure expansion chamber and a discharge passage which provides communication between the hydraulic pressure expansion chamber and the outside and which has a valve seat are formed. A valve element is arranged on the valve seat in the discharge passage. When the tubular member rotates relative to a shaft member (1) from a state where the tubular member is stationary with respect to the shaft member, the valve element is displaced from a first position for maintaining a hydraulic pressure in the hydraulic pressure expansion chamber to a second position for discharging oil from the hydraulic pressure expansion chamber to the outside.</p> |
