GB1255158A - Combustion aiding apparatus for compression-ignition internal combustion engines - Google Patents

Abstract

1,255,158. Control of burners; spark igniters. CUMMINS ENGINE CO. Inc. 22 Nov., 1968 [22 Nov., 1967], No. 55618/68. Headings F4F and F4T. [Also in Division F1] To heat the air supplied to the cylinders of a compression ignition engine having a low compression ratio, e.g. 12:1, a burner 304 directs flaming fuel-air mixture into a tube 307 having openings 311 adjacent the cylinder intake passages 258. The tube 307 is supported at opposite ends in the intake manifold 273 and the centrally located burner 304 has a pair of nozzles 305 each having an outlet 322 supplied with air under pressure from a tank (344), Fig. 13 (not shown), or by an electric motor driven compressor (402), Fig. 17 (not shown), through passages 341, 343 and 329, Fig. 7. Fuel is drawn through an orifice 323 from a float chamber 334, Fig. 6, subjected to the manifold pressure through a passage 330, by the air flow through the nozzle and the mixture is ignited by a spark plug 350, Fig. 2. Fuel may be supplied to the float chamber inlet 335 from the return line (266), Fig. 13, from the engine fuel injectors (255) which are supplied by a pump (262). The flow of air from the tank (344), Fig. 13, is controlled by a valve (347), upstream of a pressure reducing valve (346) providing a constant pressure, having a solenoid which is energized when the contacts of a thermostatic switch (354), Fig. 11 (not shown), mounted at the inlet end of a water manifold 251, Fig. 12, distributing cooling water to water passages (247, 248), Figs. 4 and 9 (not shown), in the engine cylinder block and cylinder heads, is closed. The contacts close below a predetermined water temperature, e.g. 180‹ F., and open above a predetermined temperature, e.g. 195‹ F. The thermostatic switch (354) also closes the circuit of the spark plugs 350, Fig. 2, which includes an ignition coil (351), Fig. 16 (not shown), and a motor (352) operating a vibrator. The thermostatic switch (395), Fig. 17, may close a circuit, including a battery (394), of the motor (403) of the burner air compressor (402) and the solenoid valve (387) controlling fuel flow from the main engine fuel pump to a chamber (384). A float (388) in the chamber (384) operates contacts (392) to complete the solenoid valve circuit and close the valve when the float rises in the chamber. A valve (404), Fig. 17, in the conduit (401) connecting the compressor (402) to the burner nozzle (381) is controlled in accordance with the manifold pressure to maintain a constant pressure difference. A manifold (416), Figs. 14 and 15 (not shown), for supplying air to the intake passages of an in-line engine or the cylinders of one bank of a V-8 or V-12 engine through outlet ports (417 to 420) has a nozzle (423) at one end which directs flaming mixture into a tube (428) extending along the manifold. The nozzle (423) directs mixture through a Venturi (444) in a baffle plate (442) in the manifold between the nozzle and the tube inlet and air flows from the manifold into the space between the nozzle and baffle plate to be entrained by the mixture. The tube (428) has four outlet openings (432 to 435) adjacent the manifold outlet ports (417 to 420) and the opening areas increase from the opening (417) nearest the nozzle (423) to the furthest opening (420). Details of optimum burner fuel flow rates for engine starting are given in the Specification.