Patent ID: 8151688
Filing Date: 2012-04-10
Classification: F15B,Y10T

Abstract:
1. A hydraulic circuit of a construction machine, comprising: a remote control valve; a control valve of a hydraulic pilot type with a spool for performing a stroke action by pilot pressure from said remote control valve; a hydraulic actuator whose action is controlled by said control valve; and a throttle path for returning a part of pilot oil to a tank while throttling, said throttle path being provided in a pilot line for transmitting the pilot pressure from said remote control valve to said control valve, wherein said throttle path has a variable opening area and is adapted to be closed when said spool stroke of said control valve is less than a specified stroke and to be opened from a point when said spool stroke reaches said specified stroke, said specified stroke being from a vicinity of a stroke where said hydraulic actuator starts moving.