GB755545A - Improvements in valves or like throttling devices - Google Patents

Abstract

755,545. Interconnected valves. ETABLISSEMENTS NEYRPIC. Feb. 5, 1954, No. 3510/54. Class 135. In a valve having two annular closure members closable in succession by a single control means on to primary and secondary seats, the primary seat and its closure member are rigid and the secondary seat or its closure member resilient. The primary seat is formed on the conical surface of a male seating member and the secondary seat below the primary seat either on the conical surface or a cylindrical extension thereof. As shown, concentric sleeves 12, 18, Fig. 1, constituting the primary and secondary closure members respectively sealingly surround a discharge tube 10 connected, e.g. to a reservoir and engage in succession a conically-ended seating member 30 secured by fins 31 to the tube 10 and an elastic ring 34 secured to the member 30 in a position such that when the valve is open the ring is shielded from the flow of fluid through the valve to reduce wear on the ring. The valve is operated by a plurality of spring-loaded rods 21 secured to a flange 20 on the sleeve 18 and passing loosely through holes 23 in a flange 14 on the sleeve 12. The rods being movable by a single operating member. In closing the valve, the sleeves 12, 18 initially move together, the springs 26 being strong enough to allow this, until the sleeve 12 engages the member 30, to close the valve except for minor leakages. Thence on further closing movement of the rods 21, the springs 26 are compressed so that the sleeve 18 moves relative to the sleeve 12 and engages and compresses the elastic ring 34 to ensure a fluid-tight closure. In a modification, an elastic ring 57, Fig. 4, comprising the secondary closure member, is mounted on an annular structure 56 to which operating rods 52 are secured and a sleeve 61 comprising the primary closure member is resiliently connected to this structure by studs 65 and an elastic ring 64. As shown in Fig. 4, both closure members are closed and the ring 64 . compressed. On opening the valve, pressure on the ring 64 is first relieved whence the ring 57 moves away from the cone 44 into a shielded position behind the sleeve 61 until the ring 64 urges the structure 56 into abutment with lock-nuts 67. On further opening movement both the ring 57 and the sleeve 61 move away from the cone 44 to fully open the valve.