GB267886A - Improvements in means for converting alternating current into steady continuous current - Google Patents

Abstract

267,886. Dubilier Condenser Co. (1925), Ltd., (Assignees of Nyman, A.). March 17,. 1926, [Convention date]. Vacuum apparatus, arrangements of; convert. ing pulsating currents into steady continuous currents.-Means for supplying a load such as thermionic amplifier circuits with substantially steady D.C. from an A.C. supply source comprises a thermionic rectifier with grid control and means for energizing the grids with a potential which varies in accordance with the voltage supplied to the plate circuit so as to cause the current in the latter circuit, which includes the output terminals, to be substantially constant. In one arrangement, Fig. 1, A.C. is supplied through a transformer T having a mid point tapping 11 connected to one of the output terminals 20 the other of which is connected to the plate 8 of a valve provided with two filaments 4. 5 energized by windings 9, 10. The valve is provided with grids 6, 7 which are energized with the potentials required to ensure a steady plate current by means of winding 12, 14 coupled to an inductance 15 which in conjunction with a ,condenser 16 forms a circuit tuned to a harmonic, e.g., the second harmonic, of the supply frequency. In an alternative arragement, Fig. 2, the grids of a pair of valves 23, 24, connected to produce full wave rectification at the output terminals 20, are energized by windings 27, 35 .coupled to a winding 26 in the output circuit. 'The valve filaments are supplied through a transformer 11. In each case, the output current is further smoothed by a filter circuit comprising an inductance 18 and condensers 17, 19.