Gas-fired heater esp. for vehicular passenger accommodation - incorporates electrically-insulating bushings and ring for gas mixing and filtering insert for flame monitoring

摘要

On the rear wall (14) of the combustion chamber (3) a gas mixing device (15) is installed enclosing an insert (26) in which a mixing filter (30) is spaced axially fromm a flame filter (31) and a perforated disc (32) with concentric rings of holes. Threaded retaining pins (35,36) pass through the wall (14) in paraxial bushings (37) to an insulating ring (38). For flame monitoring, one pin (35) carries an electrical connection (40) to an ionisation electrode (18). ADVANTAGE - Reliable electrical insulation accomplished in simple structure which uses mixing filter insert (or part of it) as counter-electrode for flame ionisation. monitoring.