Patent GB-754398-A (GB)
Title: Automatic controlling means for liquid fuel burners
IPC: B60H1/22
Filed: 1954-08-06
Abstract: 754,398. Vapour burners. GRAUERS, K. G. Aug. 6, 1954 [Nov. 12, 1953], No. 22939/54. Classes 75(1) and 75(3). In control means for a burner including a cut-off valve 3 controlling the supply of liquid fuel under pressure to a vaporizer 17 heated to vaporizing temperature by an electric heating resistance 20, and an electric device, for instance spark electrodes or an incandescent resistance 23, for igniting the vaporized fuel, a thermostat device, for instance a single bimetal strip or two bimetal strips 14, 25, in heat conductivity with the burner is connected (1) to a valve holding member 13 in such manner that the fuel valve 3 is retained in closed position when the temperature of the burner is below the vaporization temperature and (2) to a switch 26 in such manner that the electric circuit to the heating resistance 20 and igniter 23 is interrupted by the burner attaining a temperature sufficient for continued operation of the burner by selfvaporization, and a manually operated member 9 is arranged so that in an " off " position a cam 8 thereon retains the fuel valve 3 closed and a contact member 10 thereon interrupts the electric circuit to the heating resistance 20 and igniter 23. The cut-off valve 3 comprises an elastic diaphragm pressed by its own resilience and by a pin 4 against a seating at the end of a passage 2 conveying the fuel from a container 1. The pin 4 extends outside the valve housing 5 to abut a pivoted arm 6 urged by a spring 7 in a clockwise direction to release the diaphragm but held in the closed position of the diaphragm by the cam 8 and also by the holding member 13. The fuel is vaporized in the vaporizer 17 and passes through a nozzle 21 into a combustion tube 16 having air inlets 22 in its inlet end. The heating resistance 20 is disposed around the vaporizer 17, and the igniter 23 is disposed in the combustion tube 16. The bimetal strip 14 extends along the outside of the vaporizer 17 and the other bimetal strip 25 extends along the outside of the combustion tube 16. On turning the manually operated member 9 from the position shown the contact member 10 engages a contact 11 to energise the heating resistance 20 and igniter 23 and the cam 8 releases the pivoted arm 6 which, however, is retained by the holding member 13. After a time the bimetal strip 14 warps and the holding member 13 and pivoted arm 6 are swung upwardly by the spring 7 to release the pin 4. The fuel valve 3 is then opened by the fuel pressure and the fuel passes to the vaporizer. The mixture of fuel vapour and air is ignited in the combustion tube 16 by the igniter 23. After a further time the other bimetal strip 25 opens the switch 26 to de-energise both the heating resistance 20 and the igniter 23, the vaporizer being then kept at vaporizing temperature by heat conducted downwardly from the combustion tube. If the flame goes out the bimetal strip 25 closes the switch 26 to energise the heating resistance 20 and the igniter 23 and if the vaporizer cools below the vaporizing temperature the other bimetal strip 14 actuates the holding member 13 and the pivoted arm 6 to close the fuel valve 3. A signal lamp is connected in parallel with the igniter and the heating resistance. A needle 28 for clearing the nozzle 21 extends through a fluid tight guide in the lower end of the vaporizer and is connected by a lever and link to the contact member 10 so as to be withdrawn from the nozzle when the manually operated member 9 is turned at starting. The burner is used to heat the cooling water and electric battery of a vehicle engine. When the engine is running a sub-atmospheric pressure is created in the container 1 for closing the fuel valve 3 to shut down the burner and for supplying fuel to the container.