Patent GB-414070-A (GB)
Title: Improvements in or relating to prepayment mechanisms
IPC: G07F15/02
Filed: 1933-01-24
Abstract: 414,070. Prepayment mechanism for electricity meters. BUTHERUS, F. R., and BRITISH SANGAMO CO., Ltd., Cambridge Arterial Road, Enfield, Middlesex. Jan. 24, 1933, No. 2305. [Class 27.] Coin action, mechanical-connection and multiplecoin.-In a prepayment electricity meter, a coin is inserted through a slot 16, Fig. 1, and a shoot 11 to rest on a shelf 43 between plates 1, 2. A knob 28 on a shaft 26 is then pushed in and rotated to close the switch and advance the prepayment quantity mechanism. The shaft 26 has three wheels 18, 19, 20 which operate to advance the quantity mechanism proportionately to the value of the coin as described in Specification 346,283. These wheels are made of moulded material. The shaft 26 has a square portion 10 passing through an operating disc 9 and ending in a flange 47 which engages the coin and pushes it back, transmitting the thrust to an inturned edge 100 of the plate 1 and withdrawing a tongue 7 thereon from a hole 8 in the disc 9. The disc now can be rotated to perform its controlling functions which consist in closing the coin slit, operating the switch, and the prevention of continued movement if the coin is removed prior to the closing of the coin-slit. Coin-slit closing-devices.-A cam 32 on the disc 9 engages a star-wheel 17 to rotate the shoot portion 11 through 90‹ and thereby close the insertion slit 16. Continued rotation of the member 9 causes a cam 31 to rotate the shoot 11 into alignment with the slit after the commodity has been switched on. The shoot 11 is positioned at each actuation by a spring engaging a second star-wheel 12. The periphery of the disc 9 also actuates a spring 45 to cause this to project over the top of the shoot 11, and prevent the insertion or withdrawal of a coin. The spring 45 may be pivoted between its ends so that a coin acting against its lower end, automatically projects its upper end into slit closing position. Fraud preventing.-If a coin is withdrawn before the coin-slit is closed, the tongue 7 will enter another hole 103 on the disc 9 and prevent further rotation of this disc. Switch-closing mechanism.-The switch operating member 41 is loosely mounted on a shaft 33 rotatable in lugs 34, 35 on a plate 36 and is connected by a spring 40 to one arm 39 of a bell-crank lever 37 fixed to the shaft 33, the other arm 37<a> of this lever carrying a roller 38 with which the cam 32 coacts to rock the shaft and stress the spring 40. While the spring is being stressed, the member 41 is locked by one arm 85 of a three-armed lever 84, 85, 86, Fig. 2, entering a slot 81 in the member 41. The cam 32 consists of a spring- pressed pin 104 passing through the block 32 and carried by a part 106. The pin 104 engages the roller 38 and the part 106 the arm 86 to move the arm 85 into engagement with the member 41. Continued rotation of the disc 9 causes the cam 31 to engage the arm 84 and rock the lever arm 85 to release the member 41 which is now snapped over to close the switch by the spring 40. The rocking of the shaft 33 causes an arm 50 of a bell-crank lever 49, 50 fixed thereon to move a sleeve 56 along a square portion 57 of a screw-threaded shaft 87, the sleeve carrying a hook 58 which is engaged by a hook 64 to lock the switch in closed position. At the same time the shaft 87 is rotated by gearing from the coin-operated shaft and a disc nut 76 is moved along the shaft 87 away from the catch 64. The nut 76 is in the form of a wheel gearing with a long pinion 96 driven by the meter. Consumption of energy causes the nut 76 to travel back along the screw and ultimately release the catch 64 allowing the shaft 33 to be rocked back by a spring 52 and the switch to be opened. Instead of the tension spring 52 shown, a coiled spring surrounding the shaft 33 may be used, such an arrangement reducing the friction opposing the rotation of the shaft 57. The switch will not be held in closed position unless the nut 76 moves away from the catch 64. Movement of the nut will not occur if arrears of basic charges, such as rent, are owing so that coins then inserted go to pay off the arrears only. A pricechange train is provided in the gearing between the meter and the long pinion 96. Specification 346,282 also is referred to.