Internal-combustion engines – Combustion chamber means combined with air-fuel mixture...
Patent
1988-04-06
1989-08-08
Nelli, Raymond A.
Internal-combustion engines
Combustion chamber means combined with air-fuel mixture...
123486, 123 1A, 123 1R, 123406, 123435, 123515, F02P 514, F02M 3704
Patent
active
048542865
DESCRIPTION:
BRIEF SUMMARY
The invention refers to a device for adapting the fuel/air metering system and the ignition system of an internal combustion engine to enable the engine to be run with all normally available grades of petrol (gasoline) fuel in accordance with the preamble to claim 1.
Modern, low-emission motor vehicles are currently equipped with a three-way catalytic converter and a .lambda. sensor (oxygen sensor) in order to reduce toxic emissions. It is important that combustion should take place with a stoichiometric ratio (.lambda.=1) to enable the catalytic converter to operate at a high level of efficiency. The .lambda. sensor is therefore designed as an oxygen sensor, and forms part of a control loop for the fuel/air metering system.
The known three-way catalysts are damaged by operation with leaded fuel, so that catalyst-equipped vehicles have to be run on unleaded fuel.
However, unleaded fuel is not yet universally available in European countries outside Germany, or overseas. Therefore, in order to be able to run a catalyst-equipped vehicle in these countries as well, it is necessary to remove the catalytic converter and the .lambda. sensor to prevent them from being damaged by leaded fuel. A generally known method of achieving optimum efficiency of an internal combustion engine is to store an additional fuel/air map in the electronic control unit for the fuel/air metering system that is suitable for operation without catalytic converter (.lambda..noteq.1) as well as the fuel/air map intended for operation with catalytic converter (.lambda.=1). Switching over from one map to the other is best carried out in the workshop when the catalytic converter is removed or installed by altering the position of a switch or by changing over a connecter (PIN coding).
In spite of this means of adapting the fuel/air metering system to the different operating conditions when the catalytic converter is removed, there remains the disadvantage that the engine cannot achieve optimum efficiency since the electronic control unit for the ignition timing is programmed with a timing map that is only adapted to the low RON/MON rating of unleaded fuel, and cannot be changed. It is also generally known that motor vehicles with internal combustion engines can be suited for operation with either premium fuel or regular fuel. This is necessary for countries in which premium fuel is not universally available, or where the quality of the premium fuel available is closer to that of regular fuel as marketed in the Federal Republic of Germany.
For operation with both grades of fuel there are two different ignition timing maps for premium fuel and regular fuel programmed in the electronics that control the ignition timing, and these have to be switched over manually by the driver as required when the tank is filled. The disadvantage of this switch-over arrangement is that it requires conscious action by the driver. Should the driver forget to switch over from premium to regular grade, there is a risk of high speed knock which, as is generally known, is inaudible and especially likely to cause engine damage. Additionally, if low quality premium grade fuel is used, with values that are closer to those of regular grade, this will not normally be realised by the driver, so that he will again fail to switch over the ignition as required. Apart from the risk of engine damage, this has the further disadvantage that the maximum performance capability is not achieved and that fuel consumption and exhaust emissions will be high.
The object of the invention is to create a means of adapting the fuel/air metering system and the ignition system of an internal combustion engine to enable the engine to be operated with all normally available grades of petrol (gasoline), at the same time protecting the engine from damage and achieving optimum fuel efficiency and low pollution levels by means of optimum regulation and control of the engine, at the same time eliminating the possibility of intervention by the operator of the internal combustion engine, particularly the
REFERENCES:
patent: Re31218 (1983-04-01), Hicks et al.
patent: 2958317 (1960-11-01), McNally
patent: 3903856 (1975-09-01), McDougal et al.
patent: 4399780 (1983-08-01), Lassanske et al.
patent: 4610232 (1980-09-01), Iwata
patent: 4615319 (1986-10-01), Tomisawa
patent: 4640254 (1987-02-01), Ninomiya
patent: 4671242 (1987-05-01), Akiyama et al.
Audi AG
Nelli Raymond A.
LandOfFree
Device for adapting the air/fuel metering system and the ignitio 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 for adapting the air/fuel metering system and the ignitio, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for adapting the air/fuel metering system and the ignitio will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-898339