Patent ID: 7162946

Claim:
A hydraulic control valve comprising: a valve housing including a pump path communicating with a hydraulic pump, a tank path ( 12 ) communicating with an oil tank, first and second cylinder ports communicating with a hydraulic cylinder, and a connecting line ( 15 ) selectively connected the tank path and the second cylinder port; a control spool movably provided in the valve housing, cutting the pump path off from the first and second cylinder ports in a neutral state and selectively connecting the pump path and the tank path with the first and second cylinder ports while moving in left and right directions if pilot signal pressures are applied thereto; a holding valve ( 30 ) between the second cylinder port and the control spool, including a holding poppet ( 31 ) on the second cylinder port connected with the connecting line and a drain valve ( 32 ) supplying hydraulic oil to or cutting the hydraulic oil off from a rear pressure chamber ( 34 ) of the holding poppet ( 31 ), and cutting off the second cylinder port when the control spool is in the neutral state and holding load of the hydraulic cylinder so as not to cause natural drop of the hydraulic cylinder; and an actuating path ( 40 ) in the control spool and connecting the connecting line to the tank path when the control spool is switched to the neutral state.