HYDRAULISCHE STEUERVORRICHTUNG UND HYDRAULISCHES STEUERVERFAHREN

摘要

A hydraulic control apparatus includes two oil flow control valves (30, 32) each provided with a supply control portion (36, 38, 52, 54) for controlling an oil supply from a pressurized oil source, and a discharge control portion (40, 42, 56, 58) for controlling connection with a discharge passage. One of those oil flow control valves supplies/discharges oil to/from one of hydraulic chambers (22, 24) that are oppositely formed in a hydraulic servo mechanism. An operation direction of the hydraulic servo mechanism is performed by operating one of the oil flow control valves. The other operation direction of the hydraulic servo mechanism is performed by operating the other oil flow control valve.