Internal-combustion engines – Charge forming device – Having fuel vapor recovery and storage system
Patent
1999-03-04
2000-11-21
Moulis, Thomas N.
Internal-combustion engines
Charge forming device
Having fuel vapor recovery and storage system
123520, 123304, F02M 3304
Patent
active
06148802&
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The invention relates to a method of operating an internal combustion engine as well as an internal combustion engine especially for a motor vehicle wherein fuel from a tank is injected directly into a combustion chamber either in a first mode of operation during a compression phase or in a second mode of operation during an induction phase.
BACKGROUND OF THE INVENTION
One system of this kind for directly injecting fuel into the combustion chamber of an internal combustion engine is generally known. A so-called stratified charge operation as a first mode of operation and a so-called homogeneous operation as a second mode of operation are distinguished. The stratified operation is used especially for smaller loads; whereas, the homogeneous operation is utilized for larger loads applied to the engine. In stratified operation, the fuel is injected during the compression phase of the engine into the combustion chamber and there, directly into the vicinity of a spark plug. This has the consequence that no uniform distribution of the fuel in the combustion chamber can take place; instead, the fuel is immediately ignited by the spark plug. The advantage of stratified operation lies in that applied lower loads can be carried by the engine with a very small quantity of fuel. Larger loads can, however, not be satisfied with stratified operation. In homogeneous operation, which is provided for such larger loads, the fuel is injected during the induction phase of the engine so that a swirling and therefore a distribution of the fuel in the combustion chamber can still easily take place. Insofar, the homogeneous operation corresponds approximately to the operation of internal combustion engines wherein fuel is injected into the intake manifold in a conventional manner.
SUMMARY OF THE INVENTION
The object of the invention is to provide a method for operating an internal combustion engine as well as an internal combustion engine with which a further fuel reduction is possible.
This object is solved in a method of the initially mentioned type by the invention in that vaporized fuel is supplied to the combustion chamber in the second mode of operation from the tank. For this purpose, and according to the invention, a corresponding line is provided for an internal combustion engine of the initially mentioned type.
The fuel, which is vaporized from the tank, is therefore trapped and supplied via the line to the combustion chamber and therefore to the combustion. In this way, it is achieved that the vaporized fuel does not escape into the atmosphere and so remains unused; instead, it is achieved that this vaporized fuel is also used for driving the engine. Overall, this not only has the advantage of a further fuel reduction but also a lesser burden on the environment because of the operation of the engine.
The vaporized fuel is however not continuously supplied to the combustion chamber; instead, it is supplied only under specific conditions. According to the invention, the vaporized fuel is supplied to the combustion chamber only during the second mode of operation, that is, during the homogeneous mode of operation of the engine. In this way, it is avoided that too much fuel reaches the combustion chamber in the first mode of operation, that is, during the stratified operation.
As explained, the fuel can no longer distribute in the combustion chamber in stratified operation so that, for too large a fuel quantity, an incomplete combustion would take place in the combustion chamber. This would not only lead to an unnecessarily high fuel consumption, but also to an unwanted high generation of exhaust gas.
Because of the supply of vaporized fuel according to the invention only during homogeneous operation and not during stratified operation, the advantage of the fuel reduction because of this supply during the homogeneous operation is achieved, on the one hand, whereas, on the other hand, the disadvantage of an incomplete combustion and the like is avoided during the stratified operation.
In an adva
REFERENCES:
patent: 5170759 (1992-12-01), Ito
patent: 5479906 (1996-01-01), Collie
Moser Winfried
Philipp Matthias
Moulis Thomas N.
Ottesen Walter
Robert & Bosch GmbH
LandOfFree
Method for operating an internal combustion engine, especially o does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for operating an internal combustion engine, especially o, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for operating an internal combustion engine, especially o will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1248390