GB479782A - Improvements in or relating to gas meters - Google Patents

Abstract

479,782. Prepayment mechanism for gas meters. BINGHAM, J. H., and METROPOLITAN GAS METERS, Ltd. Sept. 22, 1936, No. 25769. [Class 27] Price - changing mechanism.-A prepayment gas meter, in which the consumer is automatically charged a reduced rate for all gas consumed in a calendar period in excess of a predetermined initial quantity charged for at a higher rate, comprises known screw - and - nut quantity mechanism 1, 2, Fig. 1, for controlling the valve, the screw 2 being rotated from the meter driven mechanism to close the valve by a long pinion 20 on a parallel shaft 18 engaging a pinion 21 fixed to the screw. The shaft 18 carries two worm wheels 17, 19, the wheel 19, when the higher rate is in force, engaging a worm wheel 12 on a shaft 10 rotated by the meter diaphragms. The shaft 18 is movable longitudinally by a spring 23 to disengage the wheel 19 and worm 12 and bring the worm wheel 17 into engagement with a worm 16 on a vertical shaft 15 which is driven by a worm and worm wheel 13, 14 from the shaft 10. The shaft 18 is held with the higher rate in force by a pivoted detent 22 against which it abuts, until the end 25 of an arm 24, rotated by the screw 2 through a Geneva-mechanism 28, 29, engages a pin 26 on the detent 22 and raises this to allow the shaft 18 to move, whereupon the lower rate comes into force. In a modification, the shaft 18 is positively shifted by the meter mechanism. The arm 24 rotates a shaft 35, Fig. 2, by engaging an arm 36 thereon, when the change-over in rate is to take place. A second arm 40 on the shaft 35 is thereby brought into the path of oscillation of the arm on a flag rod 4 of the meter so that the shaft 35 is moved longitudinally and by. means of an arcuate fork 37 shifts the shaft 18, the fork 37 engaging between two collars 38, 39 on the latter shaft. Indicators.-The initial position of the arm 24 may be varied to adjust the amount of gas charged for at the higher rate by disengaging the mechanism 28, 29 against the action of a spring and sliding the arm 24 to the required position, which is indicated by a dial 30. The dial 30 may be replaced by a dial 34 at the top of the meter casing, this dial being geared to the shaft 27 carrying the arm 24.