GB408747A - Improvements relating to prepayment meters - Google Patents

Abstract

408,747. Prepayment mechanism for meters. CHAMBERLAIN & HOOKHAM, Ltd., and JAMES, S., 4, New Bartholomew Street, Birmingham. Dec. 20, 1932, No. 36072. [Class 27.] In a two-part tariff prepayment meter, mechanism is provided which, should there be arrears of basic changes to be paid, makes available, on insertion of a coin, or supply less in amount than would be obtained for that coin if there were no arrears. A restricted supply for each coin is obtained until the arrears are paid off. After insertion of a coin and rotation of a handle e, Fig. 1, a wheel f is rotated through 180 degrees so that one of two pegs g thereon engages the end h, of a lever b carrying a mercury switch a and rocks this lever to circuitclosing position where it is held by a shoulder p on a lever n. Prepayment also actuates epicyllic or other quantity mechanism to rotate an arbor i in an anticlockwise direction, this arbor being returned to its initial position to release the lever w and open the circuit by the consumption meter and by a constantly operating electric motor or clock, the motion of the latter being correlated to the fixed charges. The arbor i may be returned by a single motor driven at a constant minimum speed when no current is being consumed and at a higher speed when current is being taken by the consumer. The arbor has fixed to it a cam j and frictionally mounted on it an arm k with a peg l located in a curved slot m in the cam so that relative movement between the cam and the arm is restricted in one direction. A peg s on the arm k presses aside the lever n to open the switch a and holds it in unlocking position against the action of a spring g by engaging a recessed shoulder r. The arm k is thus prevented from further movement in the clockwise direction, but the cam j, if coins are not inserted, continues its movement independently of the arm, the extent of this movement corresponding to the arrears of fixed changes, which must be paid before a normal supply can again be obtained. The cam in this independent movement, by engaging a pin v on one end of a bell-crank lever t, rocks the lever t so that its notched other end u is moved over the peg s. On the insertion now of a coin, the arm k and cam j are moved together anticlockwise by the arbor i until the peg s engages the overhanging end u of the lever t. This stops the arm k, the distance it has moved corresponding to the restricted supply the consumer can obtain for a coin while arrears exist. The remaining movement given to the arbor i serves to lesson the angular distance between the cam j and the peg l. When sufficient coins have been inserted to cause the end of the slot m again to engage the peg l, the arrears will have been paid off, the restricted supply lever t returned to its original position, and the arm 7c will be permitted a full movement for each coin inserted. A notch may be provided in the end u of the lever t to engage the peg s when the arrears exceed a certain amount. This will prevent any supply of current from being obtained until the excess arrears are paid.