GB1518883A - Compression ignition engine with an intake air preheating system - Google Patents

Abstract

1518883 Heating IC engine intake air CUMMINS ENGINE CO Inc 29 June 1976 27088/76 Heading F1B [Also in Division F34] Flow of fuel to the burner 34 for heating air in the engine intake manifold 36 is controlled by a metering system 40 receiving fuel at a pressure increasing as a non-linear function of engine speed from the fuel system 16 supplying the injectors 12. The system 40 operates to provide a substantially linear increase of fuel flow-rate to the burner nozzle 38 with increase of engine speed above cranking speed. The engine driven gear-pump 20 supplies fuel to a valve 22 controlled by a mechanical speed governor 26 to by-pass fuel back to the pump inlet and provide a non-linear pressure characteristic, Fig. 2 (not shown). The pressure in the passage 56 of the housing 42 is a proportion of the pressure downstream of the valve 22 determined by pressure reducing orifices 52 and 60 in a flowpath 46, 64 to the pump inlet containing a back pressure check-valve 65. A valve 68 opening at a pressure set by spring 70 having an adjustable abutment 71 opens a flow-path to the nozzle 38 via pressure reducing orifices 76 and 80. The orifice 80 is opened when the burner is to operate by a solenoid operated plate valve 86. A valve 92 opening at a higher pressure opens a further flow-path to the burner via a pressure reducing orifice 100 opening to the flow-path between the orifices 76 and 80. The opening of the valves 68 and 92 provides the desired substantially linear characteristic, Fig. 3 (not shown). A flow-path by-passing the valve 68 via a pressure reducing orifice 102 is opened by a solenoid operated plate valve 108 energized to open the flow-path below a predetermined engine cooling water temperature. The valve 86 is opened below a predetermined engine power output or intake air temperature.