Patent GB-683021-A (GB)
Title: Improvements in gas meters
IPC: G01F15/00
Filed: 1947-12-17
Abstract: 683,021. Dry gas meters. NEWTON, R. Dec. 17, 1947 [Jan. 20, 1947 ; June 19, 1947 ; Nov. 11, 1947], Nos. 33281/47, 33282/47 and 33283/47. Class 54 Means in a dry gas meter for reducing friction of the operating parts includes a reservoir located about the valve gratings and means for feeding lubricant from outside the meter casing to the reservoir, which is disposed and of a size to ensure that there is an adequate supply of lubricant to the bearing surfaces of the valves and valve covers associated with the valve gratings, the valve covers being adapted completely to surround the ports in the valve gratings at all positions of the travel of the valve covers so as to prevent escape of lubricant through the grating ports. In a closed top type gas meter, Fig. 3, lubricant is supplied to a reservoir 53, surrounding the valve gratings, by a pipe 54 having its inner end located above the reservoir and its outer end extending outside the meter casing, upturned and fitted with a sealing cap. A levelsetting pipe 55 with a downturned outer end has its inner end projecting upwards a suitable distance through a valve plate 12 which forms the bottom of the reservoir, and a drainage pipe 56 also with an outer downturned end communicates with the base of the reservoir. The sides of the reservoir may be downturned at their upper edges as at 86 to form retaining guides for valve covers 22. Each of two valve gratings on the valve plate 12 have, Fig. 2, end ports 40, 41 leading to the measuring chambers on either side of the bellows, an intermediate port 42 connected to a gas outlet passageway 25, and two inlet ports 43, 44 laterally spaced from the end ports 40, 41 and in direct communication with an inlet gas passageway. The valve covers 22 which may be wholly of metal or formed of plastic with a metal bearing surface are formed so as to completely cover the ports in the valve gratings at all positions of the travel of the valve covers. The valve covers may be of a trough shape as described in Specification 670,557 to which reference is made. The side rods and motion wires of the meter are provided with grooved bearing rollers engaging in slotted bearing brackets. The crank operating the valves may comprise, Fig. 14, a top disc 74 fixed to a crankshaft 20 and secured by a pin 77 to a centre disc 75, itself secured by a spaced pin 78 to a lower disc 76 to which is attached a bearing pin 79. Grooved rollers 81 mounted on the pins are engaged by loops 82, Fig. 15, of valve operating rods 21. Side extensions of the reservoir may direct lubricant to the side rods. In an open top type gas meter, Figs. 9, 10, a similarly formed reservoir 53 is filled, emptied and has the level of lubricant regulated by one pipe 101 opening into the base thereof and having an upturned and a downturned exterior branched end. The inlet gas pipe opens directly into the upper compartment, ports 96, 97 in the valve covers are open at the top, and the ports 40, 41, 42 in the valve gratings extend the whole width thereof. The lubricant feeding means described with reference to Figs. 2, 3 may be used with the meter described with reference to Figs. 9, 10 and vice versa.