Control circuit of hydraulic pump, has adjusting valve arranged in actuator supply path, having opening which is open-closed based on pressure difference in actuator supply path and elastic force of actuator

摘要

A valve (7) arranged in flowpath between hydraulic pump (1) and actuator (4), controls directional switching of actuator. A pilot signal generating unit arranged at downstream side of center bypass path (3), controls discharge amount of hydraulic pump. A valve (8) arranged in actuator supply path (5), has opening (9) opened-closed based on pressure difference in actuator supply path and elastic force of actuator.