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US4662335A Expired / Lapsed US ⏱️ 0.0 years remaining

Automatic control of contaminant reduction

Assignee: MAN AG
•
Filing: 1985-11-04
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Granted: 1987-05-05
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Expires: 2005-11-04
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Abstract

Abstract In an automatic control method for reduction in the level of contaminants emitted by a gas engine, the automatic control process is orientated in accordance with the reference point at which lambda is equal to unity and enriches the mixture after detecting this point by a certain step. Subsequently the instantaneous probe potential is measured and used by an automatic control circuit as a set point, which so affects the actuator for setting the air ratio that the probe potential is kept constant at this set point. The automatic control system in keeping with the invention reacts immediately in response to a disturbance and does not have to wait until a renewed search for the reference point takes place.

Inventors

  • 👤 Herbert Kleeblatt

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 08:21
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/0025; F02D41/0027; F02D19/00; F02D19/02; F02D19/021; F02D19/023; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/30

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 133 words
A method of controlling the air/fuel ratio in a gas engine, comprising the steps of: sensing the air/fuel ratio and producing a signal in response thereto, the signal being a pre-known value when stoichiometry is sensed, adjusting the air/fuel mixture until a signal of the pre-known value is sensed indicating that stoichiometry is present, then enriching the air/fuel mixture by a predetermined amount, to create a desired air/fuel ratio richer than the stoichiometric point, and storing the signal produced by that enriched mixture, the stored signal establishing a desired set point corresponding to the desired air/fuel ratio, thereafter continuously sensing the air/fuel ratio and producing signals in response thereto, and adjusting the air/fuel mixture in response to those signals so as to maintain those signals as close as possible to the set point.
Claim 2
Independent Claim 133 words
A method of controlling the air/fuel ratio in a gas engine, comprising the steps of: sensing the air/fuel ratio and producing a signal in response thereto, the signal being a pre-known value when stoichiometry is sensed, adjusting the air/fuel mixture until a signal of the pre-known value is sensed indicating that stoichiometry is present, then enriching the air/fuel mixture by a predetermined amount, to create a desired air/fuel ratio richer than the stoichiometric point, and storing the signal produced by that enriched mixture, the stored signal establishing a desired set point corresponding to the desired air/fuel ratio, thereafter continuously sensing the air/fuel ratio and producing signals in response thereto, and adjusting the air/fuel mixture in response to those signals so as to maintain those signals as close as possible to the set point.
Claim 3
Dependent Claim 17 words
A method as defined in claim 1 wherein the air/fuel ratio is sensed by a lambda probe.
Claim 4
Dependent Claim 19 words
A method as defined in claim 1, wherein the signals are fed to a microcomputer via an analog/digital converter.
Claim 5
Dependent Claim 16 words
A method as defined in claim 3 wherein the analog/digital converter has a plurality of inputs.
Claim 6
Dependent Claim 22 words
A method as defined in claim 3 wherein the microcomputer operates a valve for controlling the flow of fuel to the engine.
Claim 7
Dependent Claim 14 words
A method as defined in claim 5 wherein the valve is also manually operable.

References Cited (Backward Citations)

US4401086A Cited
US4377143A Cited
US4445481A Cited
US4434764A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-05-04 1990-11-03 1991-05-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-05-04 1994-11-03 1995-05-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-05-04 1998-11-03 1999-05-05 $7700.00 Window Closed / Lapsed

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