Patent GB-422561-A (GB)
Title: Improvements in or relating to prepayment mechanisms
IPC: G07F15/08
Filed: 1933-07-08
Abstract: 422,561. Prepayment mechanism for meters. BRITISH SANGAMO CO., Ltd., and BUTHERUS, F. R., Cambridge Arterial Road, Enfield, Middlesex. July 8, 1933, No. 19418. [Class 27] Price-changing mechanism.- In a prepayment meter mechanism arranged to operate on two tariff bases, the change from high to low tariff taking place automatically after a predetermined amount of commodity has been prepaid, the planet wheel of a differential mechanism of which the two sun wheels 1, 2 are shown in Fig. 1, transmits movement from the coin mechanism to the quantity mechanism determining the supply. When the high tariff rate is in force the wheels 1, 2 are turned in opposite directions and, when a predetermined supply has been prepaid, the wheel 2 is locked and the wheel 1 is alone effective on the planet wheel so that commodity is then supplied at a low rate. The two-tariff mechanism is more particularly for use with the prepayment electricity mechanism described in Specification 414,070. The collector sets a dial 31 to show the number of units to be prepaid at the high rate by turning in a clockwise direction a wheel 23 by inserting a screw-driver in a tapped head 24. The dial is rotated clockwise through wheels 20, 25, 26, 27, 29, 30. The wheel 20 is carried by a shaft 21 having loosely mounted thereon a wheel 18 which is clutched thereto by a friction plate 22, this plate allowing slip when the dial is being set. In setting the dial a pin 50 on a disc 51 mounted on the shaft 28 of the wheels 27, 29, is moved away from the nose 49 of a trip lever 44 which is maintained in contact with a rod 33 by a blade spring 45. After setting the dial, the rod 33 is pushed in by a button 42 against the action of a spring 52 and held in its inner position by the lever 44 engaging in a groove 43. The rod 33 has a forked arm 54 which slides a wheel 10 loose on a shaft 11 into engagement with a wheel 4 loose on a shaft 5 and forming a unit with a wheel 3 meshing with the sun wheel 1. The wheel 10 has an eccentric boss 14 slidably engaging a rod 12 on a disc 13 fixed to the shaft 11. After insertion of a coin, the wheel 1 is rotated in an anti-clockwise direction and through the wheels 3, 4, 10 and rod 12 rotates the shaft 11 which has fixed to it a wheel 17 engaging the wheel 18 and a wheel 15 which through gearing 16 rotates a wheel unit 6, 7, 8 loose on the shaft 5 so that the wheel 6 rotates the sun wheel 2 in the reverse direction to the sun wheel 1. The rotation of the wheel 18 reverses the dial and, when zero is reached, the pin 50 trips the lever 44 so that the rod 33 is moved back and the gear wheel 10 slid along the shaft 11 to mesh with the wheel 6. This locks the sun wheel 2 against rotation, and the movement of the planet wheel is determined solely by the sun wheel 1. Adjustment of the high rate is effected by change wheels 15, 16, while adjustment of the low rate is effected by the pricechange mechanism described in Specification 414,069 and located between the sun wheel 1 and the quantity mechanism. Specification 347,794 also is referred to.