Patent attributes
An adequate rotation angle is ensured and any member is not damaged due to fluid resistance even with use of highly viscous fluid. A rotating shaft (2) is provided inside a casing (1) having first divider walls (5) provided on its inner periphery and in direct or indirect contact with the rotating shaft. Second divider walls (4) are provided on an outer periphery of the rotating shaft and in either direct or indirect contact with the casing. A flow passage (4a) is provided in the second divider wall for fluid communication between the pressure chambers. A check valve mechanism has curving portions (6a) moving on and along the periphery of the rotating shaft and valving portions (6b) each joining to the curving portion. The curving portion is supported between the rotating shaft and the first divider wall. The flow passage is opened/closed depending upon a direction of fluid flow.
