437,125. Prepayment mechanism for meters. ARON ELECTRICITY METER, Ltd., and RIORDAN, E. J., 80, Salusbury Road, Kilburn, London. May 1, 1934, No. 13108. [Class 27] Coin action, mechanical - connection, with delivery proportionate to value of coin.-In meter prepayment mechanism adapted to be set according to the value of any one of different preselected coins insertable into a common rotatable coin pocket where the diameter of the coin is gauged, the setting is performed by mere rotation of a single handle connected with the coin pocket, this rotation first releasing a gauging member to measure the coin, and subsequently effecting the setting through connecting means controlled by the gauging member. In the construction shown, for use with a penny or a shilling, a slotted cylindrical coin pocket 11 is rotated from an external handle through a slippable friction coupling member 14, and has fixed to its rear end a sleeve 18 opening into an axial bore 17 in the pocket. In the bore of the sleeve 18 is an axially slidable piston 24 arranged at the end of a rod 25 passing through a reduced extension 20 of the sleeve, and normally restrained from entering the bore in the pocket under the action of a spring by engagement of an arm 27, axially movable with the piston and passing through an axial slot in the sleeve, with a raised flat 32 of a cam 31 supported by the casing 13. Upon insertion of a shilling and rotation of the pocket, the arm 27 rides down the part 33 of the cam under the action of its spring until the piston 24, moving into the axial bore of the coin pocket, is engaged and stopped by the edge of the shilling. A gearwheel 47, axially slidable on pins 49 carried by a disc 41 loosely mounted on the extension 20 of the sleeve, is urged against the arm 27 so that, during the above action, it moves to the end of the pins 49 and into mesh with a gearwheel 50 connected with the quantity mechanism. With continued movement of the pocket, the arm 27 engages a pin 49 and commences to rotate the wheel 47 to set forward the quantity mechanism. The setting action is completed by means of a spring-urged arm 56 carrying a roller 55 which co-operates with a cam 45 turning with the disc 41 and wheel 47. The action when a penny is inserted is similar, except that the piston 24 is permitted less axial movement into the bore of the pocket, so that the gear-wheel 47 meshes with a gearwheel 51 having a different gear ratio with the quantity mechanism. The commodity switch is set by engagement of one of a pair of pins 42 on the disc 41 with a lever 70 having rack teeth 72 meshing with a pinion 73 on the shaft of the switch, which is held in set position by a latch 76 until prepayment is exhausted. Coin-discharging mechanism.-At the completion of rotation of the coin pocket, the arm 27 engages one or other of a pair of edge-cams 35, 36, according to whether a penny or a shilling is in the pocket, and is thereby displaced axially so as to withdraw the piston 24 from engagement with the coin which falls through a discharge opening 39 in the coin pocket casing 13. When the amount prepayed exceeds a certain value, a pin 87 on a wheel 86 gearing with the differential element of the quantity mechanism thrusts forward a rod 81 carrying an obstructing member 80 for the discharge slot 39, so that the coin is prevented from dropping out and further prepayment is prevented. Fraud preventing.-During rotation of the coin pocket, and before the arm 27 engages a rod 49 to initiate the setting action, a peg 29 on the arm 27 passes through one or other of a pair of notches in a fixed barrier 62. The notches are so situated that the peg can only pass through if coins of correct diameter are used. Return movement of the peg 29 through the notches, before completion of the setting action, is prevented by a spring blade 65. A further spring blade 68 adjacent the cams 35, 36 prevents return movement of the arm and pocket when the cam has reached a position in which it would not also be returned by the spring actuated arm 56. When the coin pocket has completed its movement and the coin has been discharged, the arm 27 falls against the side wall of the casing 13, and the peg 29 passes through a third notch in the barrier 62 during the return movement of the pocket.