Patent GB-450339-A (GB)
Title: Improvements in or relating to prepayment meters for electricity, gas and the like commodities
IPC: G07F15/06
Filed: 1935-03-25
Abstract: 450,339. Prepayment mechanism for meters. WRIGHT, N., 15. Woodheys Drive, Sale, Cheshire, and METROPOLITAN-VICKERS ELECTRICAL CO., Ltd., 1, Kingsway, London. March 25, 1935, No. 9298. [Class 27] In prepayment meters for electricity, gas, &c. in which a fixed charge is collected by means of a clock or constant speed motor either alone or in conjunction with a charge for commodity consumed, two sets of gears are connected between the clock or constant speed motor and the commodity side of the meter differential so as to cover one range of speed changes and so that the whole movement of the clock or motor is transmitted to the differential, a device being provided to adjust the movement transmitted by at least one of the sets of gears and to 'indicate the rate of change for the adjustment in effect. In one construction, Fig. 1, a shaft O of a constant speed device drives a shaft 1 having gear-wheels 2, 3, the wheel 3 being geared to one sun-wheel 20 of an auxiliary differential D through a wheel 19. The wheel 2 drives intermittently, through an adjustable mechanism such as is described in Specification 423,438, the other sun-wheel 14 of the differential D, the planet-wheel 16 of which, through gearing 21, 22, drives one sun-wheel 23 of a differential A and either adds or subtracts in known manner the movements of the sun-wheels 14, 20. The drive from the wheel 2 includes an arm 6 carrying a pawl 7 which engages a pin 9a on a spring-controlled pawlbearing driving arm 9. A trip pin 18 carried by an adjustable indicating disc trips the pawl 7 out of engagement with the pin 9a during each revolution of the arm 6, and its position may be varied by adjusting the disc to vary the amount of movement given to the sun-wheel 14. The other sun-wheel 27 of the differential A is driven from the consumption meter and the planetary-wheel cage 29 transmits the sum of the movements of the wheels 23, 27 in known manner to the commodity side of the usual quantity-mechanism differential P. In a second construction, Fig. 2, the constant speed motor drives continuously a shaft 41 having wheels 47, 48 which drive wheels 49, 55 in opposite directions, these wheels being rigidly connected by sleeves 51, 57 with the sun-wheels 50, 56 of two epicyclic mechanisms, the other sun-wheels 43, 44 of which are connected together and secured to a shaft 42 passing through the sleeves 51, 57. The planet-wheels are carried by discs 52, 58 rotatable on the sleeves 51, 57 and locked alternately against rotation by a brake comprising a lever 62 pivoted at 80 and having two teeth 81, 82 to engage respectively with the toothed discs 52, 58. The tooth 81 is held in engagement with the disc 52 against the action of a spring 76 by a hooked catch lever 66 which is tripped by an arm 73 rotated by the constant speed motor through gearing 83 ... 88, the arm 73 being carried by an indicating disc 63 adjustably secured to the shaft of the gear 88. When the lever 66 is tripped, the tooth 82 locks the disc 58, the disc 52 being released. The lever 66 is reset and the brake 62 restored to the position shown by a second rotating arm 72 on the shaft of the gear 88 engaging and rocking a bell-crank lever 64 which carries the lever 66. The angular distance between the arms 72, 73, which determines the times the wheels 47, 48 respectively are driving the shaft 42, is adjustable by adjusting position of the disc 63. The shaft 42 is therefore driven in the forward or reverse direction according as the disc 52 or 58 is being held, and its movement together with the drive from the consumption meter is transmitted to the commodity side of the meter differential as described in connection with Fig. 1.