Patent GB-512056-A (GB)
Title: Improvements relating to prepayment meters
IPC: G07F15/06
Filed: 1937-12-29
Abstract: 512,056. Prepayment mechanism for meters. GEMEENTE-ELECTRICITEITSWERKEN AMSTERDAM. Dec. 29, 1937, No. 36040. Convention date, Dec. 29, 1936. [Class 27] Price-change mechanism.-A change-speed gear between the meter and quantity mechanisms is operated to lower the price for the commodity after a predetermined consumption and the mechanism is automatically and periodically reset with the change-speed gear at the higher rate by a constant speed motor which also collects a basic charge. In Fig. 1, the change-speed gear comprises a pair of pinions 11 and 12 mounted in a pivoted carrier 10 and alternatively engageable with pinions 13 and 14. The carrier 10 is controlled by a disc 1 driven by a pinion 3<1> and through a clutch 3 and shaft 4 from the meter mechanism. The basic charge motor 6 drives a disc 7 having an arm 8 adapted to operate a rod 9 for resetting the mechanism. When the lower rate is due, a nose on the carrier 10 drops into a slot 15 in the disc 1, the high tariff pinions 12, 14 being disengaged and the low tariff pinions 11, 13 engaged. An untoothed part 17 of the disc 1 is then opposite the pinion 3' so that the drive to the disc is interrupted. At the end of an accounting period (e.g., one month), arm 8 lowers rod 9, restores the carrier 10 and disengages clutch 3. The disc 1, being now free, is returned to its initial position by a spring 16. The initial position of disc 1 and the quantity to be consumed at the higher rate is determined by the engagement of an adjustable stop 2 on the disc with a fixed abutment. In Fig. 2, a meter driven shaft 1 is connected to a sun-wheel 11 of a summating differential by alternative gears 2 and 7 or 3 and 8, a shaft 9, and a gear 10. The other sunwheel is driven by the basic charge motor through gearing 23, 24; the planet carrier is connected with the quantity mechanism. The shaft 1 with the gears 2 and 3 is mounted in a carrier 5 slidable on a pin 6 and connected with a rocking frame 16 having a nose 17 resting on a control disc 13 driven through gears 12 and 12<1> from a pinion 4 on the meter shaft, 1. For resetting the mechanism, the basic charge motor also drives a disc 19 having a striking arm 20 adapted to engage a nose 18 on the frame 16. Initially the carrier 5 is held in its forward position against the action of a spring 23<1> with the high tariff gears 2 and 7 in mesh by the engagement of its nose 17 on the face of the disc 13. When the low tariff is due, the nose 17 drops into an aperture in the disc 13 and the carrier 5 moves inwards to engage the low tariff gears 3 and 8, the drive to the disc 13 being interrupted as in Fig. 1. At the end of an accounting period, arm 20 engages nose 18 and rocks frame 16 to withdraw its nose 17 from the aperture in disc 13 and also to move carrier 5 forward to a position in which pinion 4 disengages gear 12. Disc 13 being now free is restored by a spring to its initial position. When the arm 19 releases the frame 16, carrier 5 drops back to its initial position in which the high tariff gears 2 and 7 are in mesh and the nose 17 re-engages the face of disc 13. The initial position of disc 13 and the consumption at the higher rate is determined by an adjustable arm on the disc which engages nose 17 during resetting. Means may be provided so that the consumption at the higher rate and the accounting period are varied, according to the time of year. Specification 286,628, [Class 27], is referred to.