| 摘要 |
A hydraulic control valve for a construction machine is disclosed, which can variably control the flow of hydraulic fluid that is supplied to a hydraulic cylinder to drive a working device. The hydraulic control valve for a construction machine includes a valve block in which an inlet port and an outlet port that communicates with the inlet port is formed, a check valve provided with a first throttling portion to permit the flow of the hydraulic fluid from the inlet port to the outlet port and to variably control the flow of the hydraulic fluid from the outlet port to the inlet port, and a spool provided with a second throttling portion to variably control the flow of the hydraulic fluid from the outlet port to the inlet port through the check valve that is opened when the second throttling portion is shifted by pilot signal pressure. |
