GB596167A - Improvements relating to air heating apparatus - Google Patents

Abstract

596,167. Liquid-fuel burners. RADIATION, Ltd., and BENNETT, A. R. July 23, 1945, No. 18843. [Class 75 (i)] A spray burner suitable for use in air-heating apparatus in aircraft is provided with a fuel valve m on a spring-loaded piston n sliding in a cylinder h having one end adjacent to the nozzle c, either the cylinder or the piston being provided with an orifice or orifices permitting fuel to flow from one side of the piston to the other to set up a pressure difference, variations in which serve to vary the effective area of the valve opening k. In Fig. 1, the cylinder h is provided with orifices q, p through which the fuel may flow, an excess of pressure causing the piston to move to restrict the ports k, the rate of supply of fuel to the nozzle being thus kept substantially constant. The set of orifices q may be controlled by a piston r on a rod s connected to an extensible capsule t, another rod abutting against the inner end of this capsule and being connected to an actuating means, such as a solenoid u with push-button switches. Regulation of the air supply may be effected by mounting a fixed distributer plate d in front of the nozzle and by providing two spring-loaded slidable control plates v, w so that an excess pressure difference between the air supply chamber y and the combustion chamber a causes the control plates to move towards the distributer plates, the perforations in the two sets of plates being staggered so that this reduces the air supply. For varying the rate of air supply with the rate of fuel supply, actuation of the solenoid u may also impart a sliding movement to a part 2 provided with pins 4 engaging in helical slots in the plate w so that this sliding movement rotates the plate w relatively to the plate v which is held against rotation as by a pin-and-slot connection with the part a. A barometric capsule 3 may also be provided to actuate the part 2 in response to variations of atmospheric pressure. In Fig. 2 the fuel supply is maintained substantially constant by a needle valve 8 extending'into a bore 6 of the piston n, an excess of pressure causing the piston to move to restrict the ports k. The needle valve 8 may be carried by a piston 9 acted on by a rod 10 operable by a lever 20 or by similar means to that of Fig. 1. The air supply is regulated in a similar fashion to that of the embodiment of Fig. 1, the plate v being carried by spring blades 12, 13 so as to be axially movable with respect to the fixed plate d, both plates v, w being mounted on a helically slotted sleeve 14 engaged by pegs 18 on actuating rods 19, so that sliding movement of these rods imparts rotary movement to the plates v, w.