PUMP UNIT AND HYDRAULIC ACTUATOR

摘要

PROBLEM TO BE SOLVED: To provide a pump unit which reduces man hours for performance measurement, and to provide a hydraulic actuator.SOLUTION: A pump unit 20 integrally includes: a switching valve 51 which switches oil flow to a first chamber Y1 or a second chamber Y2 of a cylinder device 10 in which the interior is divided into the first chamber Y1 and the second chamber Y2 by a piston 12; an up-blow valve 53 (a first chamber side relief valve) which releases a pressure of a first chamber side passage 71 connected with the first chamber Y1; and a down-blow valve 54 (a second chamber side relief valve) which releases a pressure of a second chamber side passage 72 connected with the second chamber Y2.