| 摘要 |
1,032,076. Valves. C. G. D. ENGSTROM. April 14, 1964 [April 30, 1963; June 20, 1963], No. 15437/64. Heading F2V. A safety device comprises a safety valve 2, Fig. 1, and a liquid trap 3 arranged in series and controlling the relief of pressure from a conduit 1. The valve 2 comprises a piston 5 loaded by a spring 6 having a passage 9 to connect a pipe 7, leading to the trap, to a chamber 8. The trap is open to atmosphere and if the trap relieves at a pressure of P 1 and the valve alone relieves at a pressure of P 2 , the series arrangement provides opening of the valve 2 at a pressure of P 1 + P 2 . In a modification, the valve 2 is replaced by a ball co-operating with a seat, but once the ball has opened, it does not reseat with a drop in pressure. In a further modification, Fig. 2 (not shown), the valve comprises a diaphragm 30 which is fixed in the housing by a ring 34 engaging threads on the housing. The diaphragm is loaded by a spring 6 but the valve member may act by its own resilience. |
