Patent US3616274A successfully refreshed from Google Patents.
US3616274A
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Method and apparatus for monitoring exhaust gas
Assignee: Motors Liquidation Co
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Filing: 1969-11-24
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Granted: 1971-10-26
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Expires: 1989-11-24
Abstract
Abstract A solid electrolyte, electrochemical exhaust gas sensor which is self-correcting with respect to maintaining its operating temperature substantially constant. The sensor comprises two electrochemical cells sharing a common electrolyte but externally loaded differently to produce different terminal voltages. An electronically detected imbalance between the two voltages produces a thermal correction signal which activates appropriate heating or cooling means.
Inventors
- 👤 David S Eddy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 09:22
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/003; F23N5/006; F02; F02D; F02D41/00; F02D41/02; F02D41/14; F02D41/1438; F02D41/1444; F02D41/1454; F02D41/1455; G; G01; G01N; G01N27/00; G01N27/26; G01N27/403; G01N27/406; G01N27/4065; G01N27/4067
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
207 words
A method of operating an internal combustion engine including the steps of monitoring the oxygen and hydrocarbon content of said engine''s exhaust gases with a thermally-corrected, oxygen-ion-conducting, solid-electrolyte, electrochemical gas sensor having at least two pairs of electrodes on a body of said electrolyte and defining respectively first and second electrochemical cells, which are respectively loaded with high and low resistances in relation to the internal resistances of said cells to provide respectively a first voltage and a second voltage, attenuating said first voltage to a value approximating that of said second voltage; sensing any difference between said second voltage and said attenuated first voltage to determine if a thermal correction is needed; as required, producing a thermal correction signal responsive to said difference between said second voltage and said attenuated first voltage to trigger appropriate heating or cooling means for maintaining the temperature of said sensor substantially constant over the general range of cell operation and thereby rendering said first voltage virtually solely exhaust gas composition dependent; and varying an engine operating condition that alters the oxygen content of the exhaust gases in response to the first voltage and in sense to bring said first voltage to a predetermined value for the specific engine operating conditions.
Claim 2
Dependent Claim
276 words
An internal combustion engine exhaust gas sensor for measuring the chemical content of said engine''s exhaust gases through the spectrum extending from predetermined oxygen content through predetermined unburned hydrocarbons content, comprising in combination: a solid-electrolyte, electrochemical sensing device comprising a body of an oxygen-ion-conducting material and having at least two pairs of electrodes defining respectively first and second electrochemical cells, said device being interposed between said exhaust gases and a reference gas such that said cells each produce a voltage which is responsive to variations in the composition of said exhaust gases and the temperature of said body; a high resistance in relation to the internal resistance of said first cell connected across said first cell, the value of said resistance defining a load line passing substantially through the locus of points which approximately define a region on the voltage-current chart through which region the voltage-current curves for said first cell pass under conditions of differing temperatures in the general range of cell operation; a resistance of low value in relation to the internal resistance of said second cell connected across said second cell; a heater located to heat said device when energized; means to energize said heater primarily in Response to the voltage across said second cell and in sense to maintain constant the temperature of said device, while modulating the response of said second cell in accord with the voltage across said first cell in direction and amount to compensate for the influence of exhaust gas composition on the voltage of said second cell; and means responsive to the voltage across said first cell thereby measuring the chemical content of the engine''s exhaust gases.
Claim 3
Dependent Claim
288 words
An internal combustion engine exhaust gas sensor for measuring the chemical content of said engine''s exhaust gases through the spectrum extending from predetermined oxygen content through predetermined unburned hydrocarbons content, comprising in combination; a solid-electrolyte, electrocheimcal sensing device comprising a body of an oxygen-ion-conducting material and having at least two pairs of electrodes defining respectively first and second electrochemical cells in which one electrode of each pair is common to both cells, said device being interposed between said exhaust gases and a reference gas such that said cells each produce a voltage which is responsive to variations in the composition of said exhaust gases and the temperature of said body; a high resistance in relation to the internal resistance of said first cell connected across said first cell, the value of said resistance defining a load line passing substantially through the locus of points which approximately define a region on the voltage-current chart through which region the voltage-current curves for said first cell pass under conditions of differing temperatures in the general range of cell operation; a resistance of low value in relation to the internal resistance of said second cell connected across said second cell; a heater located to heat said device when energized; means to energize said heater primarily in response to the voltage across said second cell and in sense to maintain constant the temperature of said device, while modulating the response of said second cell in accord with the voltage across said first cell in direction and amount to compensate for the influence of exhaust gas composition on the voltage of said second cell; and means responsive to the voltage across said first cell thereby measuring the chemical content of the engine''s exhaust gases.
Claim 4
Dependent Claim
249 words
An internal combustion engine exhaust gas sensor for measuring the chemical content of said engine''s exhaust gases through the spectrum extending from predetermined oxygen content through predetermined unburned hydrocarbons content, comprising in combination; a solid-electrolyte, electrochemical sensing device comprising a body of an oxygen-ion-conducting material and having at least two pairs of electrodes defining respectively first and second electrochemical cells, said device being interposed between said exhaust gases and a reference gas such that said cells each produce a voltage which is responsive to variations in the composition of said exhaust gases and the temperature of said body; a high resistance in relation to the internal resistance of said first cell connected across said first cell, the value of said resistance defining a load line passing substantially through the locus of points which approximately define a region on the voltage-current chart through which region the voltage-current curves for said first cell pass under conditions of differing temperatures in the general range of cell operation; a resistance of low value in relation to the internal resistance of said second cell connected across said second cell; means for attenuating the voltage from said first cell to a value about equal to the voltage of said second cell; a heater located to heat said device when energized; and means for comparing the attenuated voltage from said first cell with the voltage of said second cell and energizing said heater when a voltage imbalance occurs to maintain constant the temperature of said device.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-25 | 1975-04-26 | 1975-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-25 | 1979-04-26 | 1979-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-25 | 1983-04-26 | 1983-10-26 | $7700.00 | Window Closed / Lapsed |