| 摘要 |
<p>1,217,930. Controlling burners. COMBUSTION ENG. Inc. 23 Dec., 1968 [26 Dec., 1967], No. 60948/68. Heading F4T. The presence or absence of a flame between two electrodes 14, 18 is detected by applying a low voltage, alternating carrier signal C to electrode 14, and detecting at the electrode 18, which picks up the signal transmitted by electrode 14, whether the signal is modulated as a result of gas ionization in the flame. As shown, an S.C.R. 56 is triggered only when the carrier signal is modulated, the signal then activating a switch 62, e.g. a reed relay in conjunction with a relay hold capacitor 68, which sends the signal to a readout 64. Upon flame cessation, S.C.R. 56 is non-conducting, switch 62 is deactivated, and an alarm 38 is activated. The alarm may be used automatically to turn off the flame gases. The electrodes may be in the form of aviation spark plugs, Fig. 7 (not shown), such that air circulation in the plugs maintains the electrodes clear of combustion products.</p> |
