Patent GB-324378-A (GB)
Title: Improvements in or relating to internal combustion engines
IPC: F02B37/00
Filed: 1923-07-28
Abstract: 324,378. Ellor, J. E., and Taylor, H. B. July 28, 1923. Starting.-An engine working normally with spontaneous ignition or electric ignition is started by means of compressed explosive mixture. In one form, Figs. 1 and 2, the cylinder head is provided with an air-inlet valve 2, an exhaust valve, a fuel-injection nozzle 4, an ignition pocket 5 containing a sparking plug 6, and a spring-loaded valve 7 for admitting compressed explosive mixture for starting from a conduit 8. A sealing valve 9 seats on an outer seating 10 at starting, and on an inner seating 11, to shut off the pocket 5 from the cylinder, during normal running. The valve 9 is controlled by a cam 12, on a manually actuated shaft, acting through a heavy spring 15 to close the valve, and a light spring 19 surrounds the valve guide. When the valve 9 is on the seating 11 it acts as a relief valve for cylinder pressures sufficient to compress the spring 15. In a modification, Fig. 4, the sealing valve 9 has a single seat and does not serve as a relief valve. The compressed starting mixture may be supplied to a distributor valve and to a conduit 8 for each cylinder by a compressor driven by an auxiliary engine and connected to a carbuiettor which also supplies the auxiliary engine. A magneto for igniting the starting mixture is driven by the auxiliary engine and connected to a distributor on the main engine. The engine is allowed to run for a few turns under the pressure of the starting mixture and the ignition magneto is then switched on. The engine is divided into two sets of cylinders, each provided with a separate fuel-injection pump 54, Fig. 4, and with separate cam shafts 35, 36 and a shaft 45 for controlling the sealing valves 9, so that one set of cylinders can be changed over from starting to normal working before the other set. Each set is provided with a handle 43 for adjusting the shaft 45 controlling the sealing valves and simultaneously adjusting the phase of the cam shafts 35, 36 by the adjustment of bevel gearing 40 through which the shafts are driven. The handles 43 may also be linked to the petrol cocks and throttle valves of the two carburettors, or to valves 57, 58 for supplying the fuel pump 54 with petrol at starting and afterwards with heavy oil. In another modification, in which the engine cylinders are not divided into two sets, a single induction pipe is employed, the carburettor is eliminated, and a nozzle in the induction pipe is supplied with rich mixture under pressure from the starting compressor. A valve admitting air to the induction pipe may be connected to the handle for adjusting the cam shaft and the sealing valve. In further modifications, the engine is supercharged by (1) an engine-driven blower connected to the carburettor; (2) a single-stage centrifugal compressor driven by a turbine driven by exhaust gases from the engine; (3) a blower driven directly by an auxiliary engine; or (4) a two-stage pentrifugal compressor 77, Fig. 12, driven by an auxiliary engine 76 for starting and by the exhaust-driven turbine 72 when the main engine 1 is running. In the latter form, the compressor 77 is connected by a conduit 66 containing a throttle 78 to the induction pipe 67 of the main engine and by a branch conduit 25 containing a carburettor 79 to the distributor valve 26 for starting. The conduit 66 also has a branch open to the atmosphere and provided with a throttle valve 80 and a carburettor 81. The carburettors 79, 81 are fed from the same float chamber 82 through separate cocks 83, 84, and the throttle valves 78, 80 are connected by linkage 85 so that when one is opened the other is closed. The auxiliary engine drives the compressor 77 through gearing 86 and a disengageable clutch 88. The main engine is started by compressed mixture supplied from the compressor 77 through the conduit 25, the distributing valve 26, and pipes 8, and is 'then run temporarily by mixture from the carburettor 81, the valve gear being adjusted to retard the timing. During normal running, air is supplied through the conduit 66 and fuel is injected from a nozzle 4. For retarding the valve timing, a cam shaft 90, Fig. 14, carrying inlet and exhaust cams 91, 92, runs at one end in a bush 93 having an external thread 95 engaging a thread 96 in the engine casting; the bush is turned by a handle 100 to move the cam-shaft axially. The cams are shaped to give a late closing of the inlet valve and a late opening of the exhaust valve in the starting position. For a low compression-ratio engine, late closing of the inlet valves is not required, but the charge is heated by means controlled automatically as described in Specification 324,726, [Class 7 (vi), Internalcombustion engines, Valves &c. for].