VALVOLA DI SICUREZZA,IN PARTICOLARE VALVOLA A 5/4 VIE,PER ORGANI DI LAVORO AZIONATI DA UN MEZZO IN PRESSIONE,AD ESEMPIO CILINDRI A DOPPIO EFFETTO PER PRESSE

摘要

A safety valve assembly for regulating the flow of a fluid under pressure to a fluid operated system e.g. a double acting cylinder element includes a housing with an inlet port, outlet ports and working ports and accommodating a pair of parallel valve spindles which are controllable by respective pilot valves so as to be shiftable between two valve positions. Each valve spindle is provided with a working piston, valve piston and a control piston which cooperates with a respective valve seat as defined by the housing. The control pistons of the valve spindles are successively disposed in a passageway extending between one of the working ports and one of the outlet ports.