SHUTOFF-SAFETY VALVE UNIT Russian patent published in 1997 - IPC

FIELD: materials handling equipment; hydraulic drive of working equipment of drop-sided trucks, timber loading and construction manipulators and other machines. SUBSTANCE: shutoff-safety valve unit has two controlled direct-action safety valves 1 with control channels 2, two check valves 3 forming two groups of valves, together with safety valves 1 which are arranged in bore of housing 4 provided with inlet holes 5 and outlet holes 6. Inlet 7 and outlet 8 of safety valve 1 and check valve 3, respectively, are placed in communication with each other and are connected to corresponding outlet holes 6. Inlets 9 of check valves 3 are connected to inlet holes 5. Two make-up valves 10 are connected by their inlets 11 to drain hole 12. Unit has boosters 13 installed in bore of housing 4 for opening shutoff members 14 of safety valves 1. Control channels 2 of boosters 13 made in housing 4 are placed in communication with inlet holes 5 of opposite group valves. Both groups of valves are arranged in one housing 4. Make-up valves 10 are installed in bores of housing 4 made square to bores for check valves 3. Inlets 9 of check valves communicate with outlets 15 of make-up valves 10, and outlets 16 of safety valves 1 communicate with drain holes 12. EFFECT: enlarged operating capabilities. 3 cl