795,736. Liquid fuel burners. AUSTRIA VERETNIGTE EMAILLIERWERKE LAMPEN - UND METALLWARENFABRIKEN AKT.-GES. May 2, 1955 [May 10, 1954; May 25, 1954], No. 12727/55. Class 75(1) A liquid fuel cooking, heating and lighting apparatus in which the burner lies above the normal fuel level in the main reservoir with fuel conveyed intermittently to the burner by supply apparatus employing heat from the burner as the source of energy serving to raise the fuel from the reservoir to the burner comprises a pump chamber connected through suction and delivery passages provided with non-return valves with the reservoir and burner, which pump chamber closed apart from the suction and delivery passages consists of a vaporizing part arranged to be continuously heated and an unheated condensation part, such that the vapour formed in the vaporization part first increases in volume owing to the heat supply to force liquid from the pump chamber through the delivery passage and vapour is then condensed by the discharge of heat therefrom in the cool condensation chamber whereby liquid is drawn into the pump chamber through the suction passage and is characterized in that the vaporizing part is constructed as a vapour-containing chamber constituting the highest part of the pump chamber while the condensation part is immediately below and in direct communication with the vaporizing part and communicates with the delivery passage whereas the suction passage communicates directly with the vapour-containing chamber. In the arrangement shown in Fig. 1 liquid fuel in a thick-walled pipe 7 provided with ribs 8 is heated by vapour burnt between perforated cylindrical walls 5 and 6 surrounded by a casing 4. The liquid fuel in the pipe 7 is vaporized in the upper part of the pipe 7 and forces the liquid fuel in the lower part downwards to force the fuel from a chamber 9 into a chamber 14 through a flap valve 15, excess fuel in the chamber 14 passing through an overflow 17 into the main reservoir 1 thus maintaining the fuel level in a channel 3 constant. When the fuel level in the pipe 7 reaches the bottom of the curve of the U-shaped pipe 11 vapour enters the container 9 to displace liquid fuel from the container 9 through a pipe 10 into the pipe 7. During this operation the flap valves 15 and 13 remain closed. The cool walls of the container 9 condense the vapour therein and fuel is sucked through pipe 12 and past the flap valve 13 into the container 9. The liquid fuel level in the pipe 7 thus rises and on reaching the heated upper portion of the pipe 7 is vaporized and the operation is repeated. In the modification shown in Fig. 2 the apparatus operates in the following manner:-the volume of vapour in the upper end of the tube 20 increases due to the burner heat and forces the level of the liquid downwards through a non-return valve 23 into a chamber 9<SP>1</SP> and 14<SP>1</SP> and channel 3. The vapour in the pipe 20 eventually reaches the lower and cool portion of the pipe 20 where it condenses thus sucking fuel from the main reservoir 1 through a pipe 19 past a non-return valve 22. The fuel in the pipe 20 again reaches a level where it is vaporized and the operation is repeated. In a further modification, Fig. 3, a chamber 30, which functions in the same manner as the pipe 20 of Fig. 2, is in the form of an annular container surrounding the lower part of the outside of the burner 5, 6 and is provided with one or more suction pipes 32. The fuel supply to the channel 37 is controlled by a valve 38. In the embodiment shown in Fig. 4 a cylinder 50 with apertures 54 is moved up and down in the main reservoir 1 by a lever 53 over a plate 49 to pump liquid fuel into a U-shaped pipe 41, 42 and a pipe 45 into a burner channel 46 any excess fuel in the channel 46 passing through a pipe 47 to the reservoir 1. The operation of the apparatus is fundamentally the same as previously described the vaporization and condensation of the fuel being effected in the U tube 41, 42. To extinguish the burner the lever 53 is depressed and held down by a catch 56 so that a scaling plate 55 purevents fuel entering the apparatus through valve 48. In a modification, shown in Fig. 5, of the vaporizer shown in Fig. 2 the top of the pipe 60 has a large diameter vaporizer pot 65 and the bottom is provided with a large container 61 so that the cycle of fuel delivery to the burner is increased in time. The container 61 is immersed in the liquid fuel in the reservoir 1 to improve the cooling of the pipe 60. A further modification to the vaporizer, shown in Fig. 6, comprises a container 62 provided at its lower end with the suction valve 22 while its upper end is at the burner level. The lines b and c show the liquid level at the beginning and end of the fuel delivery period to the burner through a chamber 64.