摘要:
There is provided a cylinder injection type internal combustion engine capable of performing stratified charge operation at the time of a vehicle speed of 120 km/h and/or an engine rotational speed of 3200 rpm to enhance the fuel efficiency and/or to observe the emission regulations. In the internal combustion engine, a stratum of air and/or air flow is formed between a fuel spray injected from an injection valve and the top face of a piston and/or the wall surface of a combustion chamber, and a face shape contrived to guide the air flow is formed on the top face of the piston. Also, the stratified charge operation can be performed even at the time of cold start or cranking.
摘要:
To provide a process for producing a cylinder block with a sleeve in which arc recesses for avoiding interference with the umbrella portions of valves are formed at an intersection between a deck face and a cylinder bore. A sleeve is cast in such a manner that it is embedded in a cylinder block with a space from a deck face simultaneously with the molding of the opening end portion of a cylinder bore and recesses in the cylinder block in the space with a bore pin mated with a sleeve.
摘要:
A piston for an internal combustion engine is provided which has at a top surface thereof a cavity for causing a mixture charge drawn from an intake port into a combustion chamber so as to flow with a rotational motion about a horizontal axis to flow toward a spark plug. A combustion chamber structure for an internal combustion engine is also provided.
摘要:
In a direct injection spark-ignition engine with a swirl fuel injector, an orifice nozzle tip has an inclined surface that is formed on the lower end face of the orifice nozzle tip and inclined by a predetermined inclination angle with respect to a reference plane normal to an orifice axis. The predetermined inclination angle is based on both an in-cylinder pressure dependent spray angle during the stratified-charge late fuel injection on the compression stroke and an in-cylinder pressure dependent spray angle during the homogeneous-charge early fuel injection on the intake stroke. The nozzle hole is formed within the inclined surface of the predetermined inclination angle.
摘要:
The invention concerns a direct injection internal combustion engine comprising a camshaft and at least two cylinders (1), having in each cylinder a mobile piston (2) associated with at least to intake valves (4, 5), each located in an induction pipes (8, 9), and at least an exhaust valve (6, 7). The displacement of said valves is independent of the rotation of the camshaft and is controlled by a computer (15). The induction pipes (8, 9) are designed to produce an air velocity field inside the cylinder (1) parallel to said cylinder axis. The computer (15) controls, cylinder by cylinder, the opening and closing times of said at lent two intake valves (4, 5) to adapt the shape of the air velocity field inside the cylinder (1) to the engine power.
摘要:
An internal combustion engine waste heat recovery system is provided in which a second heat exchanger (H2), a fifth heat exchanger (H5), a fourth heat exchanger (H4), a third heat exchanger (H3), and a first heat exchanger (H1) are disposed sequentially from the upstream side to the downstream side of the flow of exhaust gas in an exhaust passage (33) of an internal combustion engine, and water as a working medium is supplied sequentially to the first heat exchanger (H1), the second heat exchanger (H2), the third heat exchanger (H3), the fourth heat exchanger (H4), and the fifth heat exchanger (H5). Water having the lowest temperature can be supplied to the first heat exchanger (H1) on the most downstream side of the flow of exhaust gas, to which exhaust gas having a comparatively low temperature is supplied, thus increasing the heat exchange efficiency, and water having a comparatively low temperature, which has passed only through the first heat exchanger (H1), can be supplied to the second heat exchanger (H2) on the most upstream side of the flow of exhaust gas, thus cooling effectively a high temperature section immediately downstream from an exhaust valve (25) of the internal combustion engine. In this way, the high temperature exhaust passage (33) immediately downstream from the exhaust valve (25) can be cooled effectively while maintaining the efficiency of waste heat recovery from the exhaust gas of the internal combustion engine.
摘要:
A collecting exhaust port 18 provided in a cylinder head 12 is comprised of exhaust port sections 46 extending from exhaust valve bores 35 in cylinders 14, and an exhaust collecting section 47 in which the exhaust port sections 46 are collected. The cylinder head 12 includes a protrusion 49 projecting in an arch shape outside a side wall 111 of a cylinder block 11. The exhaust collecting section 47 of the collecting exhaust port 18 directly faces an inner surface of a side wall 12 of the protrusion 49. Water jackets J2 and J3 for cooling the protrusion 49 are provided in upper and lower surfaces of the protrusion 49 having the collecting exhaust port 18 defined therein. The water jackets J2 and J3 are not provided between the side wall 121 of the protrusion 49 and the exhaust collecting section 47. Thus, the compact cylinder head 12 having the collecting exhaust port 18 integrally provided therein can be formed, while avoiding the complication of the structure of a core.
摘要:
During stratified-charge combustion operation of a direct-injection spark ignition engine, at the cylinder compression stroke, a tumble is generated which flows between a spark plug electrode and a piston crown surface toward an injector. A fuel is injected from the injector in correspondence with the cylinder ignition timing by controlling the penetration of fuel spray from the injector to correspond to the tumble flow rate so that the fuel spray may go against the tumble, become a flammable mixture at the cylinder ignition timing and stay near the spark plug electrode. In the late stage of the compression stroke, diffusion of the flammable mixture is suppressed with squishes. Thus, fuel spray behavior in the combustion chamber is controlled to allow suitable mixture stratification over a wide engine operating condition range. This improves combustion quality and extends a stratified-charge combustion zone thereby providing enhanced fuel economy and power output.
摘要:
In a control system for an in-cylinder direct injection engine, an actual port intake air density ganmap is calculated based on the intake air temperature thae and the atmospheric pressure atp, a reference port intake air density ganmap* corresponding to the current operating conditions of the engine is read out of a map and compared with the actual port intake air density ganmap, and a target fuel pressure or fuel injection timing is compensatorily modified based on the comparison result. This prevents fuel spray and the tumble from being thrown out of balance due to a change in intake air temperature or atmospheric pressure thereby providing suitable mixture stratification.
摘要:
In a control system for an in-cylinder direct injection engine, during idling operation, the fuel injection timing is compensated to the advance side for each cylinder so that the rate of change in crank angular velocity becomes smaller than a preset criterion while the fuel injection pressure of an injector is gradually reduced from a reference target fuel pressure to a preset lower limit. If the rate of change in crank angular speed becomes smaller than the criterion as a result of the above compensation, the fuel injection timing is compensated to the retard side so that the rate of change in crank angular velocity becomes smaller while the fuel pressure is gradually increased to the preset upper limit. Consequently, the unbalance of fuel spray and tumble due to deviations of fuel spray penetration and the like can be eliminated thereby providing suitable mixture stratification.