GB659802A - Improvements relating to the burning of mobile fuels in fast moving gas streams - Google Patents

Abstract

659,802. Igniting burners. POWER JETS (RESEARCH & DEVELOPMENT), Ltd. July 11, 1946, No. 20748. [Class 75(iii)] A liquid fuel pressure operated apparatus for initiating the action of a device for igniting a jet or spray of fuel in a fast moving air stream comprises a spring loaded piston operating in a cylinder, one side of the piston being exposed to the fuel pressure which opposes the spring loading, the cylinder space in the other side of the piston forming or communicating with a chamber in which air is alternately aspirated and compressed by the movements of the piston, the said air being utilized to initiate the action of the ignition device. The inlet 36, Fig. 1, of the cylinder 34 is connected to a branch from the fuel supply line downstream of the fuel cock, and the piston 22 is moved under the pressure of the fuel against the action of a spring 41. Towards the end of the latter movement an extension 24 of the piston 22 actuates a metering pump plunger 25 to deliver a measured quantity of an igniter fluid through a non-return valve 26 and connection 44 to a delivery line teminating at the burner. When the plunger 25 approaches the end of its stroke it uncovers a port 27 through which the air compressed between the piston 22 and the plunger 25 is released into the delivery line to blow the measured quantity of igniter fluid into the combustion region of the burner. At the return stroke of the plunger 25, effected by a spring 43, a fresh charge of igniter fluid is drawn into the pump chamber through the inlet 42 and non-return valve 28 and the space between the plunger 25 and the piston 22 is refilled with air, on the return stroke of the latter, through a non-return valve 29. Suitable igniter fluids are mentioned, in Specification 659,795. Alternatively, the fuel may be ignited by electrical means when the air space in the cylinder 34, Fig. 2 is connected with a chamber 46 containing a diaphragm 30 loaded by a spring 31 and having a stem 47 carrying a contact 48, which bridges the contacts 32 of an igniter circuit when the diaphragm 30 is raised by the pressure of the air compressed by the piston 22. A bleed hole 33 affords a controlled leak which after an appropriate delay, relieves the air pressure sufficiently to allow the spring 31 to return the' diaphragm 30 and contact 48 to the open circuit position. The apparatus shown in Fig. 1 or 2 may be modified to act as a fuel pressure accumulator as described in Specification 588,083, [Group XXVII].