Patent GB-531825-A (GB)
Title: Improvements in coin-freed prepayment meters
IPC: G07F15/08
Filed: 1939-07-06
Abstract: 531,825. Prepayment meters with price-change mechanism. ASH, F. S., BATES, A., and METROPOLITAN-VICKERS ELECTRICAL CO., Ltd. July 6, 1939, Nos. 19744/39 and 12615/40. [Class 27] In a prepayment meter mechanism a driving means for the prepayment mechanism P is coupled with the latter through a plurality of change-speed gears each providing a plurality of velocity ratios by means of a plurality of shafts, each shaft having mounted thereon two gear wheels through one or the other, or both, of which the motion is transmitted for all ratios for which said shaft is operative. The speed gears are coupled on the one hand with a common shaft and on the other hand with respective elements of a differential gear mechanism so that the movement of a common element of the latter is proportional to the sum of the movements of said respective elements. The common element is arranged on the driven or on the driving side of the change speed gears according as the driving means correspond with the denominator or with the numerator of the charge, whereby the movement imparted to the prepayment mechanism by said driving means is proportional, or inversely proportional, to the sum of the settings of the several change speed gears according as the movement of said driving means corresponds with the denominator or the numerator of the charge. Fig. 1, shows a meter spindle 1 which imparts motion to a shaft 15 through a two-speed gear 5, 6, 7, 12, 13, 14. The shaft 15 carries a wheel 18 which can mesh with a wheel 19 on a shaft 20 when the bearing lever 22 is swung down a slot 23 in a gate 24. When moved upward the wheel 19 engages a fixed wheel 25 and locks the shaft 20. A wheel 27 on the shaft 20 engages a four times larger pinion 28 attached to a sun wheel 29 of a differential 30 the planet system 31 of which is fast on a shaft 32 which thus rotates at one eighth of the speed of shaft 20. Shaft 75 carries also a pair of pinions 35, 36 and slides freely in a fixed sleeve 37 furnished with a toothed wheel 38. A shaft 39 carries an elongated wheel 41 with which a wheel 42 is in permanent mesh. The wheel 42 is on a shaft 43 journalled at one end in a movable lever 45 and a co-operating cock piece 46 which swing about the shaft 39. A pinion 51 on the shaft 39 is connected by gearing with the other sun wheel of the differential 30, and the bearing assemblage 45, 46 can be moved axially along the shaft 39 to disconnect pinions 42 and 38 and mesh pinion 42 with pinions 36 or 35, or, further, a pinion 50 on shaft 43 with pinion 35. These lateral and swinging movements are imparted to the assemblage 45, 46 by locating the end of the spring-biassed lever 45 in one or other of wards in a gate 47. A similar arrangement is provided for shafts 60 and 57, and thus a plurality of relative speeds can be determined for both sets of gearing. A modified construction is shown in which the price change gear is on the coin side of the prepayment differential mechanism P instead of on the commodity side thereof. In another construction arcuate plates carrying different sized wheels are adjustable angularly by external knobs, and are positioned by notched quadrants with which engage pins on spring-biassed pivoted arms. Specifications 424,439, 432,575 and 454,880 are referred to.