GB1380941A - Internal combustion engines - Google Patents

Abstract

1380941 I C engine pre-combustion chambers P C VINCENT 9 May 1972 [20 May 1971] 16081/71 Headings F1B and F1F I.C. engine comprises a combustion chamber, a fuel ignition chamber provided with a fuel injector and a passageway connecting the combustion and ignition chambers, the ignition chamber having a synthetic ceramic wall capable of withstanding and retaining heat generated by combustion of fuel in said ignition chamber, to raise the temperature of the injected fuel to the temperature of burning fuel so that the injected fuel is capable of spontaneously burning upon contact with air and means to open and close said passageway in synchronism with the engine cycle, so as to open the passageway after fuel injection to enable air from the combustion chamber to enter the ignition chamber for causing partial combustion of the injected fuel to raise the temperature of the remainder of the charge for completion of combustion in the combustion chamber. Fig. 1 shows a reciprocating-piston rotary engine consisting of an annular stator 100 and a rotatable piston and cylinder assembly in which the end of each cylinder is sealed to the stator by a cuff 112. Mounted on the stator is a body 123 in which is formed a pre-heater ignition chamber which is connected by passages 113, 114,115 and 116 to the inner periphery of the stator. An injector 127 supplies fuel to the chamber which is lined with a heat insulating material and/or has an electric heating coil 126. As the ends of the passages 113 - 116 are uncovered by angular movement of the rotor, air compressed by the piston enters the chamber, which is maintained at a temperature such that the fuel immediately ignites. The burning fuel is then ejected by the pressure increase caused by the combustion into the cylinder, where combustion continues with the remainder of the compressed air. An engine driven rotatable valve 119 obturates the passages 113- 116 and is controlled by a governor sensitive to engine speed, to advance the opening of the valve (and hence the moment of ignition) as the engine speed increases. The chamber has a liner which may consist of a heat-resistant nickel alloy coated externally with silicon nitride. Fig. 4 shows a three-lobe rotary piston engine including a preheater chamber 211 connected by passages 213, 214 and 215 to the inner periphery of the cylinder, the passages being controlled by an engine driven valve 217, which again is operable by an engine speed responsive governor to vary the timing of the valve opening. Fig. 5 shows a reciprocating-piston, O.H.V. compression-ignition engine which has a swirl chamber 10 connected by a passage 26 to a pre-heater chamber 11. The passage 26 is controlled by a poppet-valve 15 actuated by an engine-driven cam and a lever-type cam follower. The cam shaft is supported in bearings formed in a block 29 which can be moved in a direction parallel to the axis of the valve in order to vary the valve lift. The block 29 is tapped to receive a square-thread quick-pitch screw 33 which is rotated by a lever 31 connected to an engine speed governor. The timing of the opening of the valve is simultaneously varied, Fig. 8, since movement of the cam shaft sprocket causes the driving chain to wrap around or unwrap from the crank-shaft sprocket 35 by an angle 37. Fig. 9 (not shown), shows a multi-cylinder in-line engine, in which there is a pre-heater chamber 311 for each cylinder 314, the passageway 315, 316 connecting the chamber to the cylinder being controlled by an engine driven valve member 313, Fig. 11 which has a recess machined in it, at positions corresponding to those of the passages. The recesses have tapered sides and the shaft can be displaced axially to vary the timing of the valve opening and the effective cross-sectional area of the passage.