US5497655A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controlling resistance heaters on exhaust gas oxygen sensors
Assignee: Ford Global Technologies LLC
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Filing: 1995-04-06
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Granted: 1996-03-12
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Expires: 2015-04-06
Abstract
Abstract A method of controlling the operation of heaters for an exhaust gas oxygen sensor as function exhaust gas temperature as compared to a first exhaust gas temperature to turn on the heaters and a second exhaust gas oxygen sensor temperature to turn off the heaters.
Inventors
- 👤 Thomas S. Gee
- 👤 Paul F. Smith
- 👤 Michael J. Cullen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 07:51
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/02; F02D41/14; F02D41/1438; F02D41/1493; F02D41/1494
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
171 words
A method of controlling a heater of an exhaust gas oxygen (EGO) sensor used by an electronic engine control system for an internal combustion engine, operating by use of a sequence of background loops beginning with the start of engine operation, including the steps of: determining whether a current background loop is a first background loop since the engine was started; if yes, initializing variables describing the condition of the heater; inferring the temperature of an exhaust gas oxygen sensor; comparing the inferred exhaust gas oxygen sensor temperature to a turn on temperature at which to turn on the exhaust gas oxygen sensor heater; if such inferred temperature is greater than the turn on temperature, turning on the heater of the exhaust gas oxygen sensor; comparing the inferred exhaust gas oxygen sensor temperature to a turn off temperature at which to turn off the exhaust gas oxygen sensor heater; and if such inferred temperature is greater than the turn off temperature, turning off the heater of the exhaust gas oxygen sensor.
Claim 2
Independent Claim
171 words
A method of controlling a heater of an exhaust gas oxygen (EGO) sensor used by an electronic engine control system for an internal combustion engine, operating by use of a sequence of background loops beginning with the start of engine operation, including the steps of: determining whether a current background loop is a first background loop since the engine was started; if yes, initializing variables describing the condition of the heater; inferring the temperature of an exhaust gas oxygen sensor; comparing the inferred exhaust gas oxygen sensor temperature to a turn on temperature at which to turn on the exhaust gas oxygen sensor heater; if such inferred temperature is greater than the turn on temperature, turning on the heater of the exhaust gas oxygen sensor; comparing the inferred exhaust gas oxygen sensor temperature to a turn off temperature at which to turn off the exhaust gas oxygen sensor heater; and if such inferred temperature is greater than the turn off temperature, turning off the heater of the exhaust gas oxygen sensor.
Claim 3
Independent Claim
34 words
A method as recited in claims 1 wherein the steps of controlling the a heater are done for a front exhaust gas oxygen sensor heater and for a rear exhaust gas oxygen sensor heater.
Claim 4
Dependent Claim
27 words
A method as recited in claim 2 wherein the step of inferring the exhaust gas oxygen sensor temperature is done as a function of exhaust gas temperature.
Claim 5
Independent Claim
192 words
A method of controlling resistance heaters of exhaust gas oxygen (EGO) sensors used by an electronic engine control system for an internal combustion engine, operating by use of a sequence of background loops beginning with the start of engine operation, including: determining whether a current background loop is a first background loop since the engine was started; if yes, initializing the variables describing the condition of the heaters; determining whether the temperature of a front EGO sensor is greater than a temperature at which a front heater is set to turn on; if yes, turning the front heater on; determining whether the temperature of the front EGO sensor is greater than a temperature at which the front heater is set to turn off; if yes, turning the front heater off; determining whether a temperature of a rear EGO sensor is greater than a temperature at which a rear heater is set to turn on; if yes, turning the rear heater on; determining whether the temperature of the rear EGO sensor is greater than a temperature at which the rear heater is set to turn off; if yes, turning the rear heater off.
Claim 6
Independent Claim
192 words
A method of controlling resistance heaters of exhaust gas oxygen (EGO) sensors used by an electronic engine control system for an internal combustion engine, operating by use of a sequence of background loops beginning with the start of engine operation, including: determining whether a current background loop is a first background loop since the engine was started; if yes, initializing the variables describing the condition of the heaters; determining whether the temperature of a front EGO sensor is greater than a temperature at which a front heater is set to turn on; if yes, turning the front heater on; determining whether the temperature of the front EGO sensor is greater than a temperature at which the front heater is set to turn off; if yes, turning the front heater off; determining whether a temperature of a rear EGO sensor is greater than a temperature at which a rear heater is set to turn on; if yes, turning the rear heater on; determining whether the temperature of the rear EGO sensor is greater than a temperature at which the rear heater is set to turn off; if yes, turning the rear heater off.
Claim 7
Dependent Claim
31 words
A method of controlling the resistance heaters of exhaust gas oxygen sensors as recited in claim 4 wherein initializing the variables describing the condition of the heaters includes turning them off.
Claim 8
Dependent Claim
63 words
A method of controlling the resistance heaters on exhaust gas oxygen sensors as recited in claim 5 wherein the EGO sensor heater is turned on when the temperature of the EGO sensor is greater than a calibrateable value that represents the temperature at which the heater can safely be turned on without cracking the EGO sensor due to moisture in the exhaust stream.
Claim 9
Dependent Claim
60 words
A method of controlling the resistance heaters of exhaust gas oxygen sensors as recited in claim 3 wherein the EGO sensor heater is turned off when the temperature of the EGO sensor is greater than a calibrateable value that represents the temperature at which the heater must be turned off so that it does not fail due to extreme heat.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-03-12 | 1999-09-11 | 2000-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-03-12 | 2003-09-11 | 2004-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-03-12 | 2007-09-11 | 2008-03-12 | $7700.00 | Window Closed / Lapsed |