| 摘要 |
PROBLEM TO BE SOLVED: To simplify a discharge passage, to improve the workability, to miniaturize a hydraulic pressure servo unit, and to reduce the weight of the device. SOLUTION: A discharge passage of a control valve 40 comprises an axial hole 33 and a radial hole 34 cut in a valve element 19, a radial hole 35 cut in a collar 46, a radial hole 36 cut in a power piston 12, a gap 55 between an outer circumferential surface of the power piston 12 and an inner circumferential surface of a hole 48 in a primary piston 43, an annular gap 56 between an inner circumferential surface of a second hole 6 in a housing 4 and an outer circumferential surface of the power piston 12, an annular gap 57 between an inner circumferential surface of the second hole 6 and an outer circumferential surface of the primary piston 43, a radial hole 58 cut in the housing 4 and a discharge outlet 59. The discharge passage is thus extended to the outer circumferential surface of the power piston 10 from the control valve 40, and further extended from the outer circumferential surface to a reservoir. Thereby, the discharge passage is simple in structure. |
