Patent GB-544557-A (GB)
Title: Improvements in coin-freed prepayment meters
IPC: G07F15/08
Filed: 1940-10-31
Abstract: 544,557. Prepayment mechanism for meters. ASH, F. S., BATES, A., and METROPOLITANVICKERS ELECTRICAL CO., Ltd., Oct. 31, 1940. No. 15909. Addition to 531,825. [Class 27] The price-change mechanism described in the parent Specification is modified in that it includes a plurality of shafts, such as 5 .. 8, disposed side-by-side and preferably co-axial, these shafts being coupled together through a plurality of countershafts 18, 19, each of which has a pair of gear wheels meshing with one wheel of each of a pair of the shafts 5 .. 8, the latter shafts having gears 9 .. 15 each adapted to be coupled with an elongated gear 33 or 34 by an idler wheel 35 or 45 movable along the shafts and elongated gears. In the construction shown embodying two change-speed gears each with an elongated gear 33 or 34 and coupled together through a differential or summating gear 59, a shaft 1 is driven by the meter mechanism either directly or through a two-speed gear (not shown) and drives the two countershafts 18, 19 through gearing 22, 21 and 24, 23. Each of the shafts 5 .. 8 comprises a sleeve loose on a fixed axle 2, the shafts 5, 7 and 8 having a pair of gears fixed thereon and the shaft 6 having a single gear 11 thereon. Gears 25, 26 on countershaft 18 mesh with gears 10,11 on shafts 5, 6 and gears 27, 28 on 19 mesh with gears 12, 14 on shafts 7 and 8. Thus all the gears 10, 11, 12 and 14 are constantly driven at different rates. Each of the elongated gears 33, 34 is adapted to be coupled to any one of the gears 9 .. 15 by means of a slidable idler gear 35 or 45. The gear 35 is mounted in a frame 40 slidable on a shaft 36 carried by end plates 37, 38 pivoted on the shaft 29 of the elongated gear 33 so that the gear 35 is always in mesh with gear 33 but can move axially. The frame 40 has an arm 42 moving in a "gate" 43 and biased downwardly by a spring 56 so that whenever the arm is in one of the slots in the gate the gear 35 is in mesh with one of the gears 9 .. 15. When the arm is in the slot marked "0" the gear 35 meshes with a fixed gear 16 and the shaft 29 is locked. The sizes and speeds of the gears 9 .. 15 are such that as the arm 42 is inserted in the successive slots the shaft 29 is driven at speeds represented by the integers 1 to 7 and corresponding for example to prices from one-halfpenny to threepence halfpenny per unit in halfpennies. The elongated gear 34 is similarly coupled to the shafts 5 .. 8 by an idler gear 45 controlled by an arm 51 working in a "gate" 52. The shafts 29, 30 of the elongated gears are respectively connected by gear trains 63, 65 and 67, 70 to the sun wheels 57, 58 of a differential gear the planet carrier 59 of which drives a shaft 60 which is thus driven at a rate corresponding to the sum of the rates at which the shafts 29, 30 are driven. The shaft 60 may be coupled with the commodity side of the prepayment mechanism in any of the ways described in the parent Specification. When the arm 51 is in the "0" position in the gate 52 the idler gear meshes with the fixed gear 16 and the shaft 30 is locked so that the motion of shaft 60 is due solely to the rotation of shaft 29. When the arm 51 is in any of the positions 1 .. 7 the price rate is increased by the corresponding number of sixteenths of a penny per unit. In order to prevent some of the lowermost charges being available a locking plate 80, Figs. 2 and 4, may be provided in conjunction with the two "gates" 43, 52. This plate lies behind the gates and its ends 81 slide in guides in frame plates 31, 32, a spring 82 biasing the locking plate to the right as shown in Fig. 4. The plate is formed with a straight upper edge 84, and a shoulder 85, and a lower edge 83 indented to correspond to the slots 0 .. 5 of the "gate" 52. When the upper arm 42 is in any of the slots ¢ .. 3¢ the lower arm can be placed in any of the slots 0 .. 7, but when the upper arm is placed in slot 0 of "gate" 42 it engages shoulder 85 and moves the locking plate 80 slightly to the left so that all the lower slots 0 .. 5 are obstructed, and the arm 51 can only be placed in slots 6 or 7 corresponding to # and <SP>7</SP>/ 16  of a penny. These being the lowest charges that can be made.