HYDRAULIC DEVICE FOR OPERATING A GRIPPER OF AN EXCAVATOR, CAPABLE OF PREVENTING A SHAKING AND A DROOPING OF THE GRIPPER MOUNTED ON A BOOM STAND OF THE EXCAVATOR

摘要

PURPOSE: A hydraulic device for operating a gripper of an excavator is provided to prevent a piston of the hydraulic cylinder and the gripper connected with the piston easily from drooping downward.;CONSTITUTION: A hydraulic device for operating a gripper of an excavator comprises a hydraulic cylinder, a solenoid valve body (30), a switch (40), a first high pressure pump (26), a second high pressure pump (28), and a one-way direction orifice type piston check valve (50). The hydraulic cylinder operates a gripper (10) mounted on a boom stand (12) of the excavator in a use or a non-use position. In the solenoid valve body, an A-port (31) connected with a small volume room (20) which is a piston bottom surface side of the hydraulic cylinder, and a B-port (32) connected with a large volume room (22) which is a piston top surface side are formed in one side. In the solenoid valve body, a P-port (33) connected with a third pump (24) which is a low pressure auxiliary pump, and a T-port (34) are formed in the other side. According to an on/off control of the switch, the B-port and the P-port are connected to enable to communicate, or the A-port and the P-port are connected to enable to communicate. The switch supplies a power in order to change a flow path which connects ports of the solenoid valve body. The first and the second high pressure pump are connected directly to the large volume room of the hydraulic cylinder. The piston check valve is assembled in the P-port of the solenoid valve body in order to maintain a hydraulic pressure supplied to the small volume room or the large volume room of the hydraulic cylinder of a specified level.;COPYRIGHT KIPO 2013