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US4281533A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for measuring soot concentration in engine oil

Assignee: Motors Liquidation Co
•
Filing: 1980-01-14
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Granted: 1981-08-04
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Expires: 2000-01-14
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Abstract

Abstract Both junctions of a thin film thermocouple are formed on one side of a glass substrate. That side of the substrate is exposed to the diesel engine oil the soot content of which is to be measured. A light source on the other side of the substrate has its radiation directed through the substrate to a location at one of the junctions so that the light is absorbed by the oil adjacent that junction to a degree determined by its soot content. The temperature of the oil and the adjacent junction are increased by an amount dependent on the soot concentration and the thermocouple output is therefore a measure of the soot concentration in the engine oil.

Inventors

  • 👤 Gary L. Eesley
  • 👤 Gregory B. DeMaggio
  • 👤 Jeffrey C. Buchholz

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 08:14
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/26; G01N33/28; G01N33/2888; G01N25/00; G01N25/18; F; F02; F02B; F02B3/00; F02B3/06

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 132 words
Means for measuring soot concentration in engine oil comprising a thin film thermocouple formed on one side of a transparent substrate and having first and second spaced junctions, the side of the substrate bearing the thermocouple being immersed in oil, means for heating the oil adjacent the first junction by an amount dependent on the soot concentration, the heating means including a source of radiation to which the substrate as well as clean oil is substantially transparent and which is absorbed by soot, and means for passing the radiation therefrom through the substrate into the oil adjacent the first junction whereby the first junction is heated when soot is present in the oil, and means for measuring the thermocouple net voltage which is a measure of the soot concentration in the oil.
Claim 2
Dependent Claim 132 words
Means for measuring soot concentration in engine oil comprising a thin film thermocouple formed on one side of a transparent substrate and having first and second spaced junctions, the side of the substrate bearing the thermocouple being immersed in oil, means for heating the oil adjacent the first junction by an amount dependent on the soot concentration, the heating means including a source of radiation to which the substrate as well as clean oil is substantially transparent and which is absorbed by soot, and means for passing the radiation therefrom through the substrate into the oil adjacent the first junction whereby the first junction is heated when soot is present in the oil, and means for measuring the thermocouple net voltage which is a measure of the soot concentration in the oil.
Claim 3
Dependent Claim 150 words
Means for measuring soot concentration in engine oil comprising, means for heating oil in a local zone including a source of radiation directed into the local zone whereby soot in the oil absorbs the radiation and heats the oil by an amount dependent on the soot concentration, means for measuring the oil temperature increase due to the absorbed radiation comprising a thin film thermocouple formed on a substrate and having first and second spaced junctions immersed in the oil, the first junction being disposed in intimate heat transfer relation to the oil in the local zone so that the first junction is affected by the said oil temperature increase and the second junction is essentially unaffected by the temperature increase to thereby generate a thermocouple voltage corresponding to the temperature increase, and means for measuring the thermocouple net voltage which is a measure of the soot concentration in the oil.
Claim 4
Dependent Claim 150 words
Means for measuring soot concentration in engine oil comprising, means for heating oil in a local zone including a source of radiation directed into the local zone whereby soot in the oil absorbs the radiation and heats the oil by an amount dependent on the soot concentration, means for measuring the oil temperature increase due to the absorbed radiation comprising a thin film thermocouple formed on a substrate and having first and second spaced junctions immersed in the oil, the first junction being disposed in intimate heat transfer relation to the oil in the local zone so that the first junction is affected by the said oil temperature increase and the second junction is essentially unaffected by the temperature increase to thereby generate a thermocouple voltage corresponding to the temperature increase, and means for measuring the thermocouple net voltage which is a measure of the soot concentration in the oil.
Claim 5
Dependent Claim 183 words
Means for measuring soot concentration in engine oil comprising, means for heating oil in a local zone including a source of radiation directed into the local zone whereby soot in the oil absorbs the radiation and heats the oil by an amount dependent on the soot concentration, means for measuring the oil temperature increase due to the absorbed radiation comprising a thin film thermocouple formed on one side of a substrate transparent to the said radiation and having first and second spaced junctions immersed in the oil, the radiation source being on the other side of the substrate for projecting radiation through the substrate toward the local zone, and means comprising an aperture in the first junction for coupling the radiation into the oil in the local zone, the first junction being disposed in intimate heat transfer relation to the oil in the local zone so that the first junction is affected by the said oil temperature increase to generate a corresponding thermocouple voltage, and means for measuring the thermocouple net voltage which is a measure of the soot concentration in the oil.
Claim 6
Dependent Claim 183 words
Means for measuring soot concentration in engine oil comprising, means for heating oil in a local zone including a source of radiation directed into the local zone whereby soot in the oil absorbs the radiation and heats the oil by an amount dependent on the soot concentration, means for measuring the oil temperature increase due to the absorbed radiation comprising a thin film thermocouple formed on one side of a substrate transparent to the said radiation and having first and second spaced junctions immersed in the oil, the radiation source being on the other side of the substrate for projecting radiation through the substrate toward the local zone, and means comprising an aperture in the first junction for coupling the radiation into the oil in the local zone, the first junction being disposed in intimate heat transfer relation to the oil in the local zone so that the first junction is affected by the said oil temperature increase to generate a corresponding thermocouple voltage, and means for measuring the thermocouple net voltage which is a measure of the soot concentration in the oil.

References Cited (Backward Citations)

US2904995A Cited
US3049964A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-08-03 1985-02-02 1985-08-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-08-03 1989-02-02 1989-08-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-08-03 1993-02-02 1993-08-04 $7700.00 Window Closed / Lapsed

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