Improvements in or relating to a.c. operated flame control devices

摘要

1,113,200. Burner flame control devices. DANFOSS A.S. 14 Dec., 1966 [8 Jan., 1966], No. 55940/66. Heading F4T. In an A.C. operated flame control apparatus having a flame sensing probe 1 and a trigger circuit comprising a capacitor C 1 charged in dependence on ionic current, a glow discharge tube 11 and an energizing element of a relay assembly the capacitor C 1 is charged by the ionic current during the first half cycle which in turn charges a second capacitor C 2 with a time constant such that the ignition voltage of the glow tube is only attained at the beginning of the third half-cycle, and the energizing element is a controlled rectifier 14 passing in the same sense as the probe, its gate electrode being influenced by the voltage derived from ignition of the glow tube. The relay assembly consists of a D.C. relay 15 shunted by a capacitor 16.