A method of starting diesel engines under load, particularly diesel engines acting directly on the driving axles of locomotives

摘要

465,943. Starting. MASCHINENFABRIK AUGSBURG - NURNBERG AKT.- GES. Sept. 17, 1935, No. 25797. Convention date, Sept. 22, 1934. Drawings to Specification. [Class 7 (v)] In a method of starting Diesel engines under load, and particularly Diesel engines acting directly on the driving axles of locomotives, throttled compressed air is introduced into the cylinders before or during the compression stroke, whilst the exhaust valve is still open, the air being so preheated that its final compression temperature, after compression to approximately 10 to 18 atmospheres, is at the commencement of fuel ignition somewhat above the ignition temperature, and further compressed air being introduced subsequently to ignition at a pressure higher than the compression pressure when the combustion pressure has fallen to the level of the pressure of the additional air. The two supplies of compressed air may be taken from separate compressors or from the same compressor ; in the latter case, only the first of the two supplies is throttled. The preheating of the compressed air may be effected in a heat-exchanger or by the combustion of fuel injected into the air. In four-stroke engines, the preheated compressed air is admitted through the inlet valve, which is opened just sufficiently to effect throttling, or through an independent throttle valve, and is partly forced out again through the exhaust valve. If the engine is to work on a twostroke cycle during the starting period, the engine is scavenged and charged by the throttled compressed air entering while the inlet and exhaust valves are open. In a two - stroke engine having piston-controlled inlet and exhaust ports, the preheated throttled compressed air is admitted through additional ports, and the cylinder is scavenged in the outer dead-centre position of the piston, either in the known manner or by the heated and throttled compressed air.