Apparatus for preventing shock by quick operation

摘要

PURPOSE: A shock protection device for the sudden operation of a hydraulic actuator is provided to prevent an impact caused by the sudden operation of a hydraulic actuator having large inertia such as a boom of an excavator and to respond rapidly for operation. CONSTITUTION: The shock protection device for the sudden operation of a hydraulic actuator comprises a main pump(1), a control spool(3) of a control valve supplying the pressure oil from the main pump(1) to a hydraulic actuator(2) and discharging the pressure oil of the actuator(2), a joy stick valve(5) decompressing the pressure oil discharged from an auxiliary pump(4), then supplying to each hydraulic unit(3a,3b) of the control spool(3), a pressure compensating valve(10) installed on pilot lines(5a,5b) connected to each hydraulic unit of the control spool(3) to delay the flow of the pilot lines(5a,5b), a bypassing line(11) detouring around the pressure compensating valve(10) on the pilot lines(5a,5b) connected to both hydraulic units(3a,3b) of the control spool(3), a pilot signal detector detecting pilot signal pressure on the pilot lines(5a,5b), and an operating valve(15) operating the bypassing line(11) according to the signals of the pilot signal detector.