GB451423A - Improvements in or relating to prepayment meter mechanism - Google Patents

Abstract

451,423. Prepayment mechanism for meters. ENGLISH ELECTRIC CO., Ltd., 28, Kingsway, London, and TILSTONE, G., Siemens Works, Stafford. Feb. 5, 1935, No. 3765. [Class 27] Price-changing mechanism.-Means for permitting a variable or adjustable lost motion, for price-changing purposes, between the coinoperated mechanism of a prepayment meter and the credit mechanism driven thereby, comprises a differential gear having one element free to rotate idly in combination with a stop device which can be set to arrest said free element after a predetermined lost motion. A shaft 7 which is turned by a setting knob through half a revolution at each coin insertion has fixed to it the carrier arm 6 of the planet pinions 1, 2 of a differential mechanism, the sun-wheels 10, 20 of which are loose on the shaft. The pinions 1, 2 mesh with each other and are supported in a frame hinged at 5 to the arm 6 and constrained by a spring 9 so that each planet pinion is held in mesh with its sun-wheel. The wheel 20 drives the crediting differential mechanism and in addition to being held by such mechanism is held frictionally through wheels 21, 22 and a spring washer 23. The wheel 10 is biassed by a spring 11 to a position where a stop 12 thereon engages a fixed stop 13. When the shaft 7 is rotated, the wheel 20 is held and the wheel 10 rotates idly until the stop 12 meets an adjustable stop 17 positioned according to the price per unit. Further rotation of the shaft 7 now drives the wheel 20 and the crediting mechanism. During the last part of the movement of the shaft 7, an extension 1a from the pinion 1 engages an auxiliary fixed pinion 14 which moves the pinion 1 out of engagement with the sun-wheel 10. This wheel 10 now moves back under action of the spring 11 to its initial position against the fixed stop 13, and the pinion 1 becomes engaged with it again. When the next coin is inserted, the action is repeated, the extension la engaging a second releasing pinion 14a. The position of the stop 17 is adjusted by an arm 15 carrying the stop and adjustable over a scale 19 by an operating and locking knob 18. The position of the stop is indicated by a pointer 16.