GB1317496A - Railway switch or points heater - Google Patents

Abstract

1317496 Railway points heater INDUSTRIELE ONDERNEMING ARMA NV 19 April 1971 [4 Feb 1970] Headings F4F and F4T A railway switch or points heater comprises a plurality of burners 3 (Figs. 1 and 2) connected via pipes 13 to a common burner supply pipe 2 for a mixture of gas and air from a gas-air mixer 1 (Fig. 5, not shown) where air is drawn in through an air induction cap (18) by means of gas supplied at pressure by a gas jet (17) connected to a gas pipe 16. The burners 3 are each connected to a common flame propagation pipe 5 which is connected to the common burner supply pipe 2 via flame flashback preventing means (Fig. 3) in the form of a plurality of narrow ducts 14 in head 25 of a brass throttle member 6. Closure of switch 28 opens a solenoid operated valve 30 in the gas pipe 16 and simultaneously actuates the ignition system to produce a periodic spark at electrodes 8 of igniter 15, fed via ignition transformer 26. The gas-air mixture fills the common burner supply pipe 2, the connecting pipes 13, all the burners 3 and also the common flame propagation pipe 5 at reduced pressure via the throttle heads 25. This mixture is ignited in the pipe 5 by a spark at the electrodes 8 and the flame is propagated via a connecting member 7, a flexibly woven asbestos tube 10 telescoping therewith and a connecting member 24 to flame chamber 23 between a ceramic burner plate 4 and a gauge 22, thus igniting every burner 3. Should a burner 3 become extinguished, it is ignited by the other burners 3 via the common flame propagation pipe 5. Igniter sparks subsequent to ignition act as reserve sparks should all the burners 3 become extinguished. The asbestos tube 10 is held in place within protective tube 11 by hose clips 12 and a tension spring 9. Each connecting pipe 13 has a left-hand and right-hand screwthread to allow adjustment of the distance f e.g. 2 or 4 mm. between burner mouth 20 and web 19 of rail 21. The adjacent parallel rectangular pipes 2 and 5 are secured by saddles (31) (Fig. 4, not shown) to supports (32) disposed beneath the nuts (33) of an existing rail weld (34) or rail-sleeper connection. Reference has been directed by the Comptroller to Specification 837,748.