GB478091A - Improvements in or relating to metering apparatus - Google Patents

Abstract

478,091. Supply meters. BRITISH THOMSON-HOUSTON CO., Ltd. Feb. 1, 1937, No. 2893. Convention date, Jan. 31, 1936. [Class 37] [Also in Group XIX] A supply meter provided with one or more counters for metering the consumption when the average load is within one of a number of predetermined ranges has a maximum demand indicator, arranged to be driven from the meter and periodically zeroized, which actuates a selector for connecting one or other of the counters for operation corresponding to different load ranges, the counters being operated according to the consumption by the discharge of an energy accumulator which is charged up during the recording period. An electricity meter drives a maximum demand indicator 7 through gearing 1, 2, 3, 4 and an actuating index 6. A cam 23 driven from a synchronous motor periodically lifts a plate 25 thereby lifting the spur-wheel 3 out of engagement with the spurwheel 4 and allowing the index 6 to return to zero under the influence of a weight 5. Two levers 8, 9 are linked by a rod 10 which operates a detent 11. In the position shown, a projection on the index 6 strikes the lever 9 and causes this to be thrown over by a spring so that the detent 11 is disengaged from a sun-wheel 12 and engaged with a sun-wheel 13. On its return to zero the index 6 strikes the lever 8, thereby returning the detent 11 into engagement with the sun-wheel 12. Each of the sunwheels 12, 13 drives a counting-mechanism 14, 15. They are loosely mounted on the shaft 16 that carries the planet-wheel 17. Fixed on this shaft is a spur-wheel 19 which engages a detent 18 during forward motion of the index 6. When the member 25 is lifted by the cam 23, the wheel 19 is engaged with the wheel 4 and is driven thereby during the return motion of the index 6, causing the planet-wheel 17 to roll on the sun-wheel 12 or 13 that is locked by the detent 11 and drive the other sun-wheel and its associated counter. The counter 14 is driven at the end of a time interval if the consumption in that interval has exceeded that at which the index 6 strikes the lever 9. The counter 15 is driven if the consumption is less than this amount. The lever 9 may be adjusted for different consumption limits. A pawl 27 engaging a ratchet-wheel 26 prevents return movement of the wheel 4 until engagement with the wheel 19 has been effected, the pawl then being lifted by a pin 28. In a modification the return of the index to zero is effected by a spring which is wound by the timing mechanism, the pawl 11 being operated by an electromagnet.