GB569274A - Improvements in or relating to fuel conditioning means and heating devices includingsuch means - Google Patents

Abstract

569,274. Air heaters. STEVENS, A. H. (Galvin Manufacturing Corporation). July 1, 1942, No. 9103. [Classes 64 (i) and 64 (ii)] [Also in Groups X, XI, XXVI and XXVII] An air heater 30, Fig. 2, is divided by a partition 31 into an upper compartment containing the combustion chamber 33 and a lower compartment containing an electrically operated fuel pump 39, fuel metering means 41, and an electric motor 38 driving a fan 49 for supplying the air to be heated and a fan 58 for supplying the air -for combustion.. The cylindrical combustion chamber 33 has end plates 61, 78 and contains a, body member 68, Fig. 3, pressed to form alternate peripheral sections 69 and fins 71, the fins communicating at their inner ends through restricted openings with the inner space which is divided by an X-shaped partition 77 into four passages 76a-76d connected at their ends to form a continuous passage. The burner 66 discharges into the passage 76a. The combustion products after passing through the passages 76a-76d are discharged into the atmosphere through tail pipes 134, 136, the space between the tail pipes allowing the escape of air from the chamber 123 to accelerate the flow of burnt gases. The fan 49 circulates air through passages 51 about the combustion chamber 33 to the discharge outlet 53 which is fitted with a pivoted flap valve 169 controlled by a bimetallic element 173. In a modification, Fig. 12, to compensate for the decreased density of the air at high altitudes and the consequent speeding up of the motor the air supply to the fuel conditioning unit 66 is controlled by louvers 201 operated by an evacuated. metal diaphragm bellows 203 containing a spring 206. The speed of the fan motor may also be regulated by a bellows controlled rhecstat resistance in the motor circuit. At greater altitudes the air supply to the heater and the fuel supply to the unit. 66 may be controlled by a bellows unit 2031 operating louvers 2011 and a valve 219a in the fuel conduit. Alternatively or additionally, bellows operated louvres may be fitted to the exhaust tail pipe 136. On, turning the fuel valve to the "off" position the engine is not immediately stopped as a bimetallic switch magneto grounding circuit remains open until the burner exhaust pipe has cooled down, thus burning up residual fuel in the burner unit. The heater may be mounted on a wheeled carriage and be used for heating aeroplane engines for starting purposes as shown in Fig. 17., the hot air being conducted through a flexible conduit 353 releasably connected to a duct 348 to the engine cowls 346. The wheels of the carriage may be raised within the heater housing the base of which is fitted with a sled member. Specifications 569,276 and 569,302 are referred to.