GB373614A - Improvements in and relating to prepayment mechanism for meters - Google Patents

Abstract

373,614. Prepayment mechanism for meters. FERRANTI, Ltd., BATT, F. H., and WHITEHEAD, M., Hollinwood, Lancashire. Jan. 21,1931, No. 2011. [Class 27.] Prepaying basic charges.-In prepayment mechanism for meters in which a controlling member is moved in one direction by coin operation and in the other both by a consumption meter and bv a torque-producing means independent of the consumption, the angular motion derived from the torque-producing device is limited positively in correspondence with the amount of fixed charge and the speed of said device is varied automatically with this amount so that the time during which the fixed charge is collected is substantially constant. The invention is described as applied to the prepayment electricity meter described in Specification 369,959. The subtractive sunwheel of the switch tripping differential is operated from the planet carrier spindle 12a, Fig. 3, of a second differential gear 10, 11, 12, the sun wheel 10 being operated through a gear wheel 80 by the consumption meter and the sun wheel 11 by Ferraris motor 20 through gearing 21 .. 28. A cam 35, Fig. 4, with an indent 35a for controlling a switch 36, 37 in the circuit of the Ferraris motor 20, is connected to the wheel 11, this cam 35 being set to a position corresponding to the amount of the basic charge and rotated through gearing 21, 29, 81, 30 .. 34 until the indent 35a allows the switch 36, 37 to open and stop the motor 20. The speed of the motor disc 43 is controlled by a brake magnet 42 pivoted at 42a and moved against the action of a spring 53 by vertically slidable guided member 54 having a pin 82 which is acted on by a cam 41. The cam 41 is rotated to position the magnet 42 by a key spindle 46 operating through gear wheels 47, 48, a pawl 51 allowing rotation of the wheel 47 in one direction only. A pin 44 on the cam 41 engages during resetting only with a pin 45 on the switch cam 35 so that operation of the spindle 46 by a key sets the cam 35 to the amount of the basic charge and at the same time adjusts the magnet 42 in accordance with that amount. In order that the main circuit switch of the prepayment meter may be maintained in the open position owing to arrears in fixed charge, the tripping switch member is formed as a sector-shaped member 60, Fig. 5 (not shown). Specification 346,538 is referred to.