Patent GB-722727-A (GB)
Title: Improvements in and relating to coin mechanisms for prepayment meters for gas and electricity and other purposes
IPC: G07F15/02
Filed: 1953-03-02
Abstract: 722,727. Prepayment meters. UNITED GAS INDUSTRIES, Ltd., and MIDLAND BANK EXECUTOR & TRUSTEE CO., Ltd., [Representatives of CHARLES, A.], and CHARLES, J. A. March 2, 1953 [March 3, 1952], No. 5543/52. Class 27. Bi-coin prepayment mechanism for a gas, electricity or other meter has the number of coins of one value that can be inserted in succession limited by a counting element, such as a spring- loaded ratchet wheel 1, and when the limited number is reached, a coin of the second, normally higher, value must be inserted to trip a catch 14 and allow the counting element to return to zero, the catch being tripped only when the handle 23 of the coin holder has been moved to the extent necessary to move closure means over the coin slots. The ratchet wheel is rotated step-by-step by a spring-loaded pawl 7 which is pivoted on the striker 4 for the lower value and engages a stop 10 so that it rotates into engagement with the ratchet wheel as the striker moves down. If the mech-. anism is such that both strikers move down on insertion of a coin of the higher value, the stop 10 is mounted on the second striker so that, when the second striker 11 moves down, the stop still holds the pawl out of engagement with the wheel but, if the strikers operate independently, the stop is fixed in position. To determine the number of coins of the lower value that can be inserted in succession a stop member is fitted on the ratchet wheel and finally contacts a stop 17; the stop member may comprise one or more adjustable or fixed pins or an exchangeable sector plate 16 or may have two relatively adjustable parts. When a coin of the higher value is subsequently inserted, a projection, such as the stop 10, on the striker 11 rotates a spring-loaded release element 18 to bring a surface 20 on it into the path of a pin or cam surface 21 fitted eccentrically on the shaft 22 of the handle 23. Rotation of the handle 23 will then, after the coin slots have been closed, rotate the element 18 so that it disengages the catch 14 and allows the wheel to return to zero. The rotary cam plate 18 may be replaced by a spring-loaded lever pivoted on the second striker and having a cam surface for releasing the catch 14 and a projection or toe that lies in the path of the pin 21 and is operated by it as soon as the coin slots are closed. In a modification, Fig. 7, of this lever, for ensuring that the counting element is not allowed to return to zero until the coin of higher value has been discharged from the coin-holder, the lever 30, which is pivoted on the second striker at 31, has its top end shaped so that, as the second striker moves down, it pivots within the limits set by a stop 35 and brings a cam projection 34 below a roller 24 on the catch 14, without touching the roller. When the coin-holder is fully rotated to discharge the coin, the pin 21, acting on the surface 38, moves the lever so that the projection 34 is in a position to operate the catch 14 as the striker returns to its normal position. The parts of the lever 30 that co-operate with the pin 21 may be arranged out of the plane of the lever so that it does not foul the pin if the coin holder is turned in the absence of a coin that moves the striker 11. The lever 30 may operate as an intermediate member between the cam plate 18 and the catch 14 and the rotary cam plate may be replaced by a longitudinallymovable bar acting directly or through a multiplying lever on the lever 30. Specification 400,636 is referred to.