Internal-combustion engines – Charge forming device – Fuel injection system
Patent
1995-01-04
1996-11-12
Argenbright, Tony M.
Internal-combustion engines
Charge forming device
Fuel injection system
123492, F02D 4134
Patent
active
055729754
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
This invention relates to a device and method for regulating the start of fuel injection in an internal combustion engine.
Because of the growing demand for minimizing emissions from Otto engines an increasing amount of interest has been shown in sequential computer controlled injection of fuel to the inlet valves. Sequential injection, where the fuel is injected individually for each cylinder to the inlet valve, where the cylinder is already in or at the beginning of the intake stroke, provides more precise dosing of the fuel before each combustion. There are a number of patents on computer controlled sequential injection. In U.S. Pat. No. 4,785,784 and U.S. Pat. No. 4,961,411 two computer controlled injection systems are described in which two injections per cylinder take place for each intake stroke, and in which the second injection provides a correcting quantity if the fuel requirement has been changed since the first injection was initiated. The purpose of this is to ensure a faster response in transient load cases. The two-stage injection in these patents generally takes place as a split injection, and also mainly whilst the inlet valve is open. Other solutions for reducing emissions include atomization of the fuel by evaporation on beating elements inserted in the intake duct immediately upstream from the inlet valve. Patents U.S. patent Application No. 4,967,706(=EP,A,343652) and DE,C,3426469 describe loose inserts which are heated with PTC elements. The disadvantage of these is that after the engine has warmed up the elements are cooled by the air flow, which renders evaporation difficult unless the heating plate is continuously heated electrically, and that the current consumption is very high, particularly in the case of a cold start. Other solutions are described in patents DE,A,4020266 and DE,A,4020267, where nearing elements are drilled into the cylinder head near the walls of the intake ducts, the disadvantage here being that the entire cylinder near constitutes a cooling body during the warming up phase, thereby necessitating a high current consumption for the intended heating of the walls. U.S. patent Application No. 4,378,001 describes a variant with the heating plate recessed in the intake manifold. U.S. patent Application No. 5,056,495 describes a heating plate permanently arranged in the intake manifold, on to which the fuel is injected directly for further distribution to the intake duct. The above-mentioned solutions involve directed injection to a heating plate which requires heating and hence continuous current consumption. U.S. patent Application No. 5,048,500 describes a heating plate which can be swivelled into the air flow and is arranged upstream of the inlet valve, but where the fuel nozzle is directed toward the heating plate arranged in the intake duct upstream from the inlet valve.
SUMMARY OF THE INVENTION
The invention is applied advantageously to Otto engines with electronic, computerized control of preferably sequential fuel injection. The object of this invention is to ensure that most of the fuel is injected to the inlet valve of the internal combustion engine, so-called indirect injection, immediately before the inlet valve begins to open, enabling a high proportion of the evaporation heat prevailing along the walls of the intake duct to be used for evaporating the fuel. The fuel is preferably injected to the valve rod close to valve head, or directly on to the valve head on the respective inlet valves, as a result of which the hottest sections, close to the combustion space, receive a shower of fuel which improves the evaporation and atomization of the fuel before the opening of the inlet valve. Very good evaporation of the fuel is achieved quickly with atomizing injectors to provide a homogeneous fuel-air mixture essential for complete combustion and the lowest possible emissions. In engines with two or more inlet valves per cylinder injectors are used for each cylinder, with a number of injection pens corresponding to the number of
REFERENCES:
patent: 4378001 (1983-03-01), Takeda et al.
patent: 4646698 (1987-03-01), Inoue et al.
patent: 4785784 (1988-11-01), Nanyoshi et al.
patent: 4911131 (1990-03-01), Nakaniwa et al.
patent: 4961411 (1990-10-01), Oshiage et al.
patent: 4967706 (1990-11-01), Van Wechem et al.
patent: 5048500 (1991-09-01), Curhan
patent: 5056495 (1991-10-01), Yamashita et al.
patent: 5113833 (1992-05-01), Nagano et al.
patent: 5159914 (1992-11-01), Follmer et al.
patent: 5190012 (1993-03-01), Takahashi
Gillbrand Peter
Tegnelius Lars
Argenbright Tony M.
Saab Automobile Aktiebolag
LandOfFree
Device and method of regulating the start of fuel injection in a does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device and method of regulating the start of fuel injection in a, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device and method of regulating the start of fuel injection in a will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-555534