Stereo lambda control

Internal-combustion engines – Charge forming device – Including exhaust gas condition responsive means

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

123698, F02D 4114

Patent

active

052675483

DESCRIPTION:

BRIEF SUMMARY
FIELD OF THE INVENTION

The invention relates to a method and an arrangement for the adapted precontrol and feedback control of the air/fuel mixtures to be supplied to the two fuel-metering devices of an internal combustion engine, which has two separate exhaust-gas channels with each channel having a lambda probe and a catalytic converter.


BACKGROUND OF THE INVENTION

Such a method and an apparatus for carrying out the method are known, for example, from a system by the applicant for the precontrol and feedback control of a 12-cylinder spark-ignition engine which has two cylinder banks with each bank having six cylinders. The fuel-metering devices are designed as injection devices. The intake pipes are separated from each other, and there are two separate tank venting valves. The adapted precontrol and feedback control are carried out by two mutually separate individual apparatus, each apparatus being assigned to a respective cylinder bank.
A similar method as well as a corresponding arrangement is also disclosed in U.S. Pat. No. 4,383,515. However, here only one precontrol value dependent upon engine speed and load without adaptation is utilized and only the exhaust gases of the two cylinder banks having separate exhaust-gas probes are detected. Tank venting is not provided.
U.S. Pat. No. 4,683,861 discloses an arrangement for venting a fuel tank utilizing a lambda control as well as an adaptive precontrol. In this connection, the basic adaptation in the lambda control loop for the computation of the metered fuel is only then released when the quantities of fuel originating from tank venting are negligible.
Methods of the type mentioned at the beginning are referred to as stereo lambda control. The separate exhaust-gas channels with a lambda probe and a catalytic converter in each channel are characteristic of stereo lambda control. The exhaust pipes may be united downstream of the catalytic converter. The intake lines need not be completely separate from each other, as in the case of the exemplary application described, instead air may be taken in jointly for both banks through a main pipe.
Adapted precontrol and feedback control is understood as being the process by which precontrol values for setting the air/fuel mixture, as a rule preliminary injection times, are determined in dependence upon values of operating variables. The precontrol values are chosen such that a desired lambda value is to be specifically achieved in the particular operating state, especially the lambda value 1, in the case of lean concepts a lambda value greater than 1. If deviations from the desired lambda value occur, they are corrected. In order to allow for system-immanent disturbance quantities, an adaptation is also carried out, that is the precontrol values are corrected with integral results of the value of the feedback control manipulated variable. As a result, system deviations remain within narrow limits, which results in fast correction and a low tendency to oscillate of the arrangement for adapted precontrol and feedback control.
In the case of a stereo lambda control, individual disturbances, for example different air leakage rates and different through-flow rates of the fuel-metering devices, act on each of the two cylinder banks. According to the state of the art, allowance is made for this independence of the two cylinder banks from each other by the method for adapted precontrol and feedback control being carried out separately for each bank, in an apparatus provided separately for this in each case. This leads to a relatively high cost of the overall apparatus for stereo lambda control.


SUMMARY OF THE INVENTION

The invention is based on the object of providing a method for stereo lambda control which manages with a single apparatus for the adapted precontrol and feedback control of the two fuel-metering devices for two cylinder banks of an internal combustion engine. The invention is also based on the object of providing an apparatus for stereo lambda control which operates according to such a method.
The

REFERENCES:
patent: 4127088 (1978-11-01), Ezoe
patent: 4383515 (1983-05-01), Higashiyama et al.
patent: 4683861 (1987-08-01), Breitkreuz et al.
patent: 4831992 (1989-05-01), Jundt et al.
patent: 5072712 (1991-12-01), Steinbrenner et al.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Stereo lambda control does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Stereo lambda control, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stereo lambda control will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2009885

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.