Patent GB-432576-A (GB)
Title: Improvements in and relating to prepayment meters
IPC: G07F15/06
Filed: 1934-01-30
Abstract: 432,576. Prepayment mechanism for meters. ASH, F. S., 20, Malvern Avenue, Flixton, Lancashire, and ASSOCIATED ELECTRICAL INDUSTRIES, Ltd., Crown House, Aldwych, London. Jan. 30, 1934, No. 3179. [Class 27] In a prepayment meter of the kind having arrangements for collecting a basic charge, the arrangements being such that until the basic charge has been paid the quantity of commodity or primary units received per coin inserted is less than is obtained after payment of the charges, the sun-wheel 5, Fig. 4, of the prepayment differential, the other sun-wheel 1 of which is driven from the coinmechanism, is driven from the meter rotor through an epicyclic differential mechanism SD, the two sun-wheels 7, 10 of which are geared and rotate together during the consumption of the primary units, whilst during the consumption of the secondary units (after payment of the basic charge) the sun-wheel 7 alone rotates to operate the prepayment differential. The sun-wheel 5 is driven by gearing from a shaft 44 carrying the planetary cage 45 of the mechanism S D, the sun-wheels 7, 10 being loose on this shaft. The wheel 7 is driven through wheels 8, 9 from the meter rotor and is rigid with a wheel 16 meshing with the wheel 14 of a unit 14, 15 slidable on a shaft 13. The wheel 15 meshes with the wheel 17 of a unit 17, 18 fixed to a shaft 21 which drives the shaft 13 through gears 19, 20, the shaft 13 having fixed to it a wheel 12 meshing with a wheel 11 which is rigid with the sun-wheel 10. When the wheels 14, 16 are in mesh, the sunwheels 7, 10 are driven together and commodity is supplied at the primary rate. After consumption of a predetermined number of primary units the wheels 14, 15 are moved along the shaft 13 against the action of a spring 38 to disengage the wheels 14, 16 so that the wheel 10 is no longer driven and the wheel 7 is alone effective to drive the commodity sun-wheel 5. The unit 14, 15 is moved by a spring-controlled lever 34 normally held out of action by a catch which is released by a trip-arm 24 when a wheel 25, fixed to a shaft 23 to which the arm 24 is also fixed, reaches its zero position as indicated by a dial 28 and fixed pointer 29. A wheel 22 loose on shaft 23 but connected to wheel 25 by a spring 26 meshes with the wheel 18 of the unit 17, 18. A spring 27 returns the wheel 25 and shaft 23 to zero position under control of the meter rotor acting through the gearing 9, 8, 16, 14, 15, 17, 18, 22, and assists the meter rotor during the consumption of primary units. To reset the mechanism, when the secondary rate is in force, a shaft 30, Fig. 3, having a slotted head 32 is pushed in against a spring 33 and rotated. A wheel 31 on the shaft is thereby engaged with the wheel 25 which is rotated away from zero to a setting indicated by the dial 28, the spring 27 being wound up. A collar 40 on the shaft 30 presses back the lever 30 which is again retained by its catch, and the spring 38 moves the unit 14, 15 back into mesh with the wheel 16. The wheel 25 is prevented from moving past zero or past the maximum setting by a pin 42 thereon coacting with a stop 43. Specification 286,803, [Class 27], is referred to.