GB836791A - Improvements in and relating to gas volume control mechanism - Google Patents

Abstract

836,791. Gas meters. UNITED GAS INDUSTRIES Ltd. June 12, 1957 [March 12, 1956], No. 7669/56. Class 54. A dry gas meter can be set to deliver a predetermined volume of gas by mechanism which is similar to prepayment mechanism and comprises a single quantity wheel 12 engaged by a pawl with a domed part 60 of an operating shaft 28 for setting it forward, differential quantity mechanism 10, 11, 14 geared to a measuring-out worm 15 driven by the metering spindle of the meter and a pawl 40 which engages a ratchet-wheel 36 to prevent return of the shaft 28 to its initial position under the action of a spring 35 until, just before the predetermined volume has been delivered and a control cam 20 is about to close the meter inlet or outlet valve, the pawl 40 is disengaged under control of the cam 20. The pawl 40 is mounted directly on, or operated by, a spindle 41 carrying a two-part lever 42, 45 in which the part 45 is adjustable relative to the part 42 by an eccentric bolt 46 and carries a projection lying in the path of a dog 44 on the control cam. The forward setting movement of the spindle 28 is limited by a pin 37 on the ratchet-wheel 36 engaging a fixed stop 38 and its initial position by a pin 33 on a setting disc 31 engaging a radial arm 34 on the spindle. The disc 31, which bears a graduated scale, can be angularly adjusted to vary the position of its stop-pin so that the quantity to be delivered can be varied and can be locked in position by a fixed pin engaging between tooth spaces 47 in its periphery. A pinion 21, in fixed relation with the driving member 17 of a Geneva mechanism connected to the control cam 20, drives a gear 22 and a drum indicator 24 showing the amount of gas available or consumed.