Internal-combustion engines – Charge forming device – Fuel injection system
Reexamination Certificate
1998-10-27
2001-05-01
Kwon, John (Department: 3747)
Internal-combustion engines
Charge forming device
Fuel injection system
C123S590000
Reexamination Certificate
active
06223730
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a fuel injection control system for an internal combustion engine and more particularly to a control system for improving the starting performance of an internal combustion engine.
2. Description of Related Art
Conventionally, it is known to inject a relatively large amount of fuel at a timing which is not synchronous with a suction stroke, as a fuel injection control carried out when an internal combustion engine is started. Fuel evaporated before the suction stroke is sucked into cylinders and is burned, thereby starting the internal combustion engine. By increasing the fuel injection amount, the fuel (fuel evaporated and sucked into the cylinders) necessary for the start-up is assured.
It is also known, because the evaporation amount of fuel changes depending on the engine temperature (cooling water temperature), to correct the fuel injection amount at the time of starting in accordance with the cooling water temperature.
Further, Japanese Examined utility Model Publication No. 1-21156 proposes it is known to improve the starting performance of an internal combustion engine, to learn the relation between the fuel injection amount at the time of engine starting and a time actually required for start-up, and to increase or decrease the fuel injection amount at the time of the next engine starting, on the basis of the learned result, so as to reduce the starting.
At the time of so-called cold engine starting which is a start-up when the engine temperature is low, however, an evaporation amount of fuel is small and even if the fuel injection amount is increased, and a misfire occurs. There is consequently a problem that exhaust emission gets worse.
SUMMARY OF THE INVENTION
It is a first object of the invention to provide a fuel injection control system of an internal combustion engine, which can improve the starting performance of the internal combustion engine and can especially improve the starting performance during cold engine starting.
It is a second object of the invention to provide a fuel injection control system of an internal combustion engine, that can shorten the starting time of the internal combustion engine.
According to the present invention, a fuel atomization device is provided to atomize fuel injected at the time of engine starting. The fuel atomization device may be a type that increases fuel pressure to a higher value at the time of engine starting than after the engine starting. Alternatively, the fuel atomization device may be a type that supplies assist air to the injected fuel.
Preferably, an intake valve is opened for a longer period at the time of engine starts than after the engine starting, so that more fuel may be supplied to an engine cylinder.
Preferably, a fuel leakage which may occur during engine stop is estimated, and the amount of fuel to be injected at the time of next engine starting after the engine stop is corrected by the estimated amount of fuel leakage.
Preferably, a change in the cylinder pressure between the compression stroke and the combustion stroke is calculated, and the fuel injection at the time of engine starting is corrected by the cylinder pressure change.
Preferably, fuel injection timing at the time of engine starting is retarded relative to that of post-engine starting.
Preferably, the amount of injected fuel adhered to an intake port and not supplied into an engine cylinder after the closing of an intake valve is estimated, and the amount of fuel to be injected next is corrected thereby.
Preferably, the amount of fuel is divided into two fuel injections at the time of engine starting, in the event that it is too large to be injected at one time relative to the opening period of an intake valve.
Preferably, the amount of intake air supplied for an engine idle speed control is reduced at the time of engine starting, so that air-fuel mixture is enriched in fuel.
REFERENCES:
patent: 5465701 (1995-11-01), Hunt
patent: 5482023 (1996-01-01), Hunt et al.
patent: 5542394 (1996-08-01), Tomisawa
patent: 5743236 (1998-04-01), Kawakami
patent: 5954025 (1999-09-01), Kanamaru et al.
patent: 5979400 (1999-11-01), Nishide
patent: 5992374 (1999-11-01), Morikawa
patent: 1-21156 (1989-06-01), None
patent: 2-46043 (1990-03-01), None
patent: 5-45762 (1993-11-01), None
patent: 2685963 (1997-08-01), None
Hasegawa Jun
Isobe Daiji
Kondo Wakichi
Yamashita Yukihiro
Denso Corporation
Kwon John
Nixon & Vanderhye PC
LandOfFree
Fuel injection control system of internal combustion engine does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Fuel injection control system of internal combustion engine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fuel injection control system of internal combustion engine will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2558424