AXIAL PISTON PUMP AND MOTOR OF CAM PLATE TYPE

摘要

PROBLEM TO BE SOLVED: To provide an axial piston pump and a motor of cam plate type that reduces vibration and noise. SOLUTION: In an axial piston pump and a motor of cam plate type, a cylinder block 20 is provided with arc-like cut-off portions 22 corresponding to the respective cylinders. Each cut-off portion 22 is communicated with the corresponding cylinder 9 via a small hole 21 such that a working fluid within the cylinder 9 partially passes in or out of the arc-like cut-off portion 22 through the small hole 21 in the course of reciprocating movement of the piston 11 in the cylinder 9 during its operation. As a result, the pressure in the cylinder 9 varies to reduce vibration and noise in the pump motor.