Patent GB-550789-A (GB)
Title: Improvement in prepayment mechanism for meters
IPC: G07F15/04
Filed: 1941-10-15
Abstract: 550,789. Prepayment mechanism for meters. LANDIS & GYR SOC. ANON. Oct. 15, 1941, No. 13268. Convention date, Oct. 16, 1940. [Class 27] In a multi-coin mechanism provided with means for setting the quantity mechanism according to the value of the inserted coin, the member actuated by the consumer is a rotary disc provided with fingerholes. In the construction shown in Fig. 1, a disc 1 fixed to a shaft 12 is provided with finger-holes 2, 3, 4 corresponding to three values of coins which can be inserted in a common slot 5 which may also be formed in the disc. The disc is normally kept in the position shown, in which a pin 7 bears against a fixed. stop 10, by a spring 11. A fly 9 driven by disc 1 controls the rate of rotation of the disc. When a coin has been inserted in the slot 5 a finger is inserted in the hole 2, 3 or 4 corresponding to the value of the coin and the disc is then rotated clockwise until the finger bears against a stop 19. The disc is then released and is returned by its spring 11, and on this return movement the quantity differential gear 67 is rotated through an angle proportionate to the coin value, the coin, when thrust into the coin carrier, actuating a setting mechanism according to its diameter. In the case of an electricity meter the actuation of the quantity differential also closes a switch 33 for the supply. When the coin is inserted in the slot 5 it falls into a coin shoot having a base piece formed by a cradle 16 pivotally mounted with some friction on the shaft 12 and which carries the finger stop 19 and is normally kept in the position shown by a spring-loaded pivoted stop 14. When the disc 1 has been rotated by the operator's finger a cam 13 moves the stop 14 down opposite a notch 18 in the cradle, so that when the finger reaches the stop 19 it can rotate the cradle slightly while the stop 14 enters the notch 18; this rotation brings a slit 17 in the cradle in line with the coin shoot so that coin now passes through the slit to the money-box (not shown). In the arrangement shown the coin corresponding to the finger-hole 2 has the smallest value, that corresponding to 3 has the middle value, and that corresponding to 4 the highest value. A middle value coin 72 has been inserted and is shown resting on the cradle 16. In this position it has raised an arm 57 pivoted at 53 until a notch 55 is opposite a disc 44 loose on the shaft and held by a spring 60 against a stop 61. The operator now inserts a finger in the hole 3 and rotates the disc 1 and shaft 12. A cam disc 20 on the shaft 12 engages a two-part lever 23, 27 and rocks it counter-clockwise so that an arm 38 slides from under a half-cylinder 39 on a shaft 40. When lost motion 42, 43 has been taken up, a disc 41 on the shaft 12 rotates the disc 44 which enters the notch 55 and locks the arm 57. When the finger in the hole 3 has reached the stop 19 a step 47 on the disc 44 abuts against the arm 57 and prevents further rotation of the shaft 12 and disc 1. During the rotation of the disc 44 a pawl 51 on an arm 50 fixed to the disc slips over a ratchet wheel 62 loose on the shaft 12 and the spring 60 is stressed. The operator's finger is now withdrawn from the hole 3 and the disc 1 is returned by its spring 11 to its normal position. The spring 60 now returns the arm 50 and disc 44, and the pawl 51 drives the wheel 62 back until the disc abuts the stop 61 as before. The wheel 62, which is rotated through an angle corresponding to the value of the inserted coin, drives through gearing 64 an indicator 65 and one sun wheel 66 of the quantity differential gear. As the other sun wheel 68 is held fast by the meter gear 71 the planet wheel 67 is rotated and drives the shaft 40 carrying the half-cylinder 39 through the angle appropriate to the value of the coin. Shortly before the disc 1 reaches its position of rest the cam disc 20 releases the lever part 23; the part 27 is now rotated clockwise by its spring 36 until the end of the arm 38 bears against the cylindrical surface of 38 which acts as a stop, while the switch 33 is closed by its spring, this spring being connected by a link 32 to the lever part 23 which is pivoted at 26 on the part 27 and bears against a fixed stop 29 acting as a temporary fulcrum. The meter mechanism 71 gradually returns the half cylinder 39 to the normal position shown, so that when the quantity paid for has been consumed the arm 38 can slip under the flat part of the half cylinder and the lever part 27 rocks sufficiently to raise the pivot 26 of the lever part 23 and cause the switch 33 to open, the two parts of the lever assuming the position shown in which a stop 30 on 23 bears against 27. If a coin of the smallest value (and largest size) is inserted the arm 57 is raised until notch 54 is opposite disc 44, and the latter can turn only until the step 46 abuts the arm 57, this rotation causing the pawl 51 to click over one or two teeth only of the wheel 62. If a coin of the highest value is inserted the notch 56 is brought opposite the disc 44 and the stop 48 comes into use: If the disc 1 is rotated without a coin being inserted a step 45 on the disc 44 abuts the arm 52 before the pawl 51 has passed over a tooth on the wheel 62 and thus the meter mechanism is not affected. The apparatus may be arranged so that the clockwise rotation of the disc 1 effects the prepayment, the pawl and roatchet mechanism 51, 62 being reversed. In order to ensure that the disc 1, when once it has started to turn in either direction, must complete its predetermined rotation before it can be reversed, the disc 41 may be provided with two oppositely-toothed ratchet wheels, one for each direction of rotation. These ratchet wheels are adapted to be engaged, one at a time, by a double pawl. When the disc is rotating clock-wise one limb of the pawl prevents backward movement, but when one of the steps on the disc 44 abuts the arm 52 it moves this arm slightly along its pivot shaft 53 against a spring, and this movement is utilised to rock the pawl so as to move the first limb of the pawl out of engagement with its ratchet wheel and to bring the second limb of the pawl into engagement with its ratchet wheel, thus permitting backward movement of the disc 1 but not forward movement. When the disc 1 has returned to its normal position a cam on the disc 41 again rocks the double pawl.