CAB HOISTING HYDRAULIC DRIVE Russian patent published in 2002 - IPC

FIELD: applicable in excavators and other building machines. SUBSTANCE: the cab hoisting hydraulic drive has a hydraulic pump connected through a hydraulic line to a three-line two-position gas distributor, in whose neutral position the working fluid is fed to the control hydraulic system, and in the working position - to the piston cavity of the hydraulic cylinder through a check valve, thus accomplishing the cab hoisting. The hydraulic cylinder rod cavity is permanently connected to the drain. Connected to the hydraulic line between the hydraulic cylinder piston cavity and the check valve is a controllable check valve, whose tap is connected to the drain, with an adjustable normally-closed throttle, whose function accomplishes the exhaust hole, when it is actuated the cab is lowered. The safety valve protects the hydraulic distributor, check valve, controllable check valve are combined in a single unit joined to the hydraulic cylinder, the distributor and the controllable check valve are controlled remotely, or joined to the hydraulic cylinder is the check valve with throttle communicating with the hydraulic cylinder piston cavity. Simultaneous switching of the hydraulic distributor and the controllable check valve is impossible. EFFECT: simplified construction and enhanced reliability of cab hoisting hydraulic drive. 2 dwg