CRANE HYDRAULIC DRIVE (DESIGN VERSIONS) Russian patent published in 1999 - IPC

FIELD: hoisting-and-transportation facilities; hydraulic drives of self-propelled boom cranes. SUBSTANCE: according to first design version, crane hydraulic drive has winch hydraulic motor, boom hoisting and brake release hydraulic cylinders and overload safeguard. Brake release hydraulic cylinder is supplied through OR valve. Electromagnetically controlled hydraulic distributor electrically coupled with overload safeguard is installed between one of inputs of OR valve and supply hydraulic line. Two pressure transmitters are coupled with overload safeguard, one of transmitters being connected with load hoisting line, and the other, with piston space boom hoisting hydraulic cylinder. According to second design version, crane hydraulic drive has winch hydraulic motor, boom hoisting and brake release hydraulic cylinders and overload safeguard. brake release hydraulic cylinder is supplied through electromagnetically controlled hydraulic distributor electrically coupled with overload safeguard. Two pressure transmitters are coupled with overload safeguard. One of transmitters is connected with load hoisting line, and the other, with piston space of boom hoisting hydraulic cylinder. EFFECT: prevention of sagging of hoisted load when hydraulic distributor providing control over winch is cut into operation. 3 cl, 2 dwg