GB729314A - Improvements in and relating to prepayment gas meters - Google Patents

Abstract

729,314. Prepayment gas meters. SMITH METERS, Ltd., and MIDLAND BANK EXECUTOR & TRUSTEE CO., Ltd., [Representative of CHARLES, A.], and CHARLES, J. A. Feb. 26, 1953 [Feb. 28, 1952], No. 5299/52. Class 27. [Also in Group XXIX] In a prepayment gas meter, a shut-off or inlet valve has two concentrically or co-axially disposed seatings 1, 2, Fig. 1, of which one seating is closed before the other so that between the times of closing of the two seatings gas at a restricted rate of flow is permitted to pass the valve. The valve pad 5 first engages the auxiliary seating 2 thus restricting the flow of gas to that which passes through the annular space between the two seatings until the pad displaces the seating 2 against the action of a leaf spring 6 or a counterweighted lever and engages the main seating 1 when the gas flow is completely arrested. A higher rate of restricted flow may be obtained by the provision of holes or notches 7 or longitudinal grooves in the outer peripheral face of the seating 2. The auxiliary seating may, alternatively, be a volute spring having its largest convolution secured within the main seating 1 or a loosely fitting sleeve surrounding the latter. In Fig. 5, the seatings are formed integrally with a moulded or diecast body 13 and are closed successively by a compressible portion 20 and a larger diameter portion 17 of the valve pad. Holes 16 and notches 15 may be provided to obtain the desired rate of restricted flow. In any of the constructions the valve pad may be connected to its arm by a spring-loaded spherical connection to permit relative angular movement. The seatings may be made from a material, such as graphite, not subject to corrosion.