GB639309A - Electric current regulator - Google Patents

Abstract

639,309. Control systems for consumption apparatus. CLEMENTSON, S. P. May 19, 1948, No. 13559. [Class 38 (iv)] In a regulating system for an alternating current circuit of the kind in which the circuit is periodically interrupted for an adjustable interval, the switch for interrupting the circuit is a rotary one, driven by a synchronous motor and is arranged to " make " and " break " whilst the current wave is passing through zero. A further switch allows selection of the ratio of the number of half-cycles during which the circuit is energized to the number of half-cycles that it is un-energized. In the arrangement shown a load L is supplied from an A.C. source X, Y through a rotary distributer switch c, d in series with a selector switch g, the wiper c of the former being driven by a four-pole synchronous motor band the fixed contacts d, each of which corresponds to a half-cycle of the supply, being connected in any desired number in the load circuit by the contact f of the selector switch. In a modified arrangement the rotary switch comprises segments mounted on a synchronously-driven shaft making contact with a stationary or adjustable brush or brushes, different segments or numbers'thereof occurring in different positions along the shaft. The selector switch determines the number or size of the segments brought into circuit. Radio interference suppressors may be connected across the rotary switch, the mains, or both. The selector switch may be actuated manually, or automatically, say, by a thermostat.