Patent GB-673392-A (GB)
Title: Improvements in or relating to starting systems for internal combustion engines
IPC: F02N7/00
Filed: 1950-02-14
Abstract: 673,392. Turning-gear. BENDIX AVIATION CORPORATION. Feb. 14, 1950 [March .9, 1949], No. 3779/50. Class 7(v) [Also in Group XIII] In a starter system for an internal-combustion engine comprising a starter motor 16, Fig. 1, a generator 10 (see also Group XIII) for producing vapour under pressure for driving the starter motor 16, control means, such as an electric switch 92, Fig. '3, and a button 94, for energizing the generator 10, Fig. 1, and means, for example a high temperature electric switch 86, responsive to the temperature of the vapour to de-energize the generator when the vapour temperature has reached an unsafe value, there is provided means, such as a centrifugal switch 76, responsive to the starter motor speed for de-energizing the generator when the motor has attained a given speed. Upon closing switch 92, Fig. 3, and depressing starter button 94 a relay is energized which, after releasing button 94, will remain energized across one of its own contacts so that current from battery 90 flows through the relay coil, the normally-closed high-temperature switch 86 and the centrifugal switch 76 to earth whilst closure of another relay contact energizes the motor of a water pump 68, fuel pump 14, fan 20 and spark plug 18, the latter being connected through a booster coil. The pump 14, Fig. 1, draws fuel from a tank 12 and passes it through the hollow shaft of fan 20 to a rotating disc incorporating radial fuel nozzles 26; the fuel from the nozzles is mixed with air drawn into a preheat chamber 54 by the fan 20 and the mixture is ignited in the combustion chamber 64 by spark plug 18. The burning gases are forced over the water tubes 44, 46 and exhaust through outlet 66. Whilst the generator is building up steam pressure the water pump 68 is byepassed by a valve 80, and at the same time the generated steam is supplied to the starter motor 16 in order to crank the engine; oil is supplied to the steam by a lubricator 74. The motor 16, shown as being of the vane type, is permanently engaged to the engine but if piston or turbine type motors are used, means will also be provided for disengaging the motor from the engine. The switch 86 opens to shut down the system in response to excessive steam temperature as detected by a thermostat 22; upon a given steam temperature being attained, the byepass valve 80, also controlled by the thermostat, will permit the pump 68 to draw water from a water jacket 52 and direct it to the generator in quantities dependent upon the steam temperature, a decrease in temperature giving rise to a reduction in pump output. When the starter motor 16 has reached a given speed the centrifugal switch 76 opens and closes down the system. In order to expel all the burnt gases a "cool-off" switch -84 is provided which closes upon a given exhaust temperature being attained and connects the fan motor 56 directly to the battery 90. The system may be used to start any number of engines such as all the engines of a multi-engined aircraft; any suitable fluid may replace the water, and the pressure may be generated by any other suitable 'means.