HYDRAULIC SYSTEM Russian patent published in 2002 - IPC

FIELD: hydraulic systems for driving working organs, possibly in different installations, automatic lines of machine tools, transport vehicles, assembling lines, for example for mounting inner races of bearings onto wheel axles of railway road cars. SUBSTANCE: hydraulic system includes two coaxially mounted hydraulic cylinders of working equipment with spring-loaded centers arranged in rods one towards another and two hydraulic cylinders of lifter mounted in parallel one with another under center line between hydraulic cylinders of working equipment; distributing device for controlling hydraulic cylinders of working equipment and lifter, pump station and pipelines forming supply lines connecting distributing device with rod cavity and with cavity for extending rod of each hydraulic cylinder; high pressure and lower pressure lines connecting pump station with distributing device; draining line connecting distributing device with hydraulic tank joined with inlet of pump station. The last is provided with pressure-difference valve placed in high- pressure line and connected by its outlet with inlet of distributing device; control hydraulic units arranged in supply lines of each hydraulic cylinder of working equipment. Said cylinder is telescopic one and it has additional rod and piston forming together with sleeve of hydraulic cylinder additional cavity communicated through additional supply line and through distributor with inlet of pressure-difference valve. EFFECT: enhanced reliability of hydraulic system. 6 cl, 1 dwg