US5435170A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for fluid quality sensing
Assignee: Individual
•
Filing: 1993-12-30
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Granted: 1995-07-25
•
Expires: 2013-12-30
Abstract
Abstract A method and apparatus for determining the quality of a lubricant by its solvating effect on an insoluble (resin) matrix to which charged groups have been covalently bound. The solvating effects are measured electronically as a variation in conductivity or capacitance of the resin matrix with respect to temperature. The apparatus includes a metal mesh housing containing e.g. milligram amounts of charged resin beads. A metal probe is fitted in the containing mesh and makes contact only with the resin beads. The entire device is immersed in the lubricant and the electrical conductivity or capacitance is measured from the probe to the mesh through the resin beads. Lubricant degradation is measured as e.g. a decrease in electrical conductivity through the resin beads with respect to an increase in the lubricant's solvent polarity.
Inventors
- 👤 Paul J. Voelker
- 👤 Joe D. Hedges
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:50
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/26; G01N33/28; G01N33/2888; G01N27/00; G01N27/02; G01N27/22; G01N27/221
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
46 words
A fluid sensor comprising: a housing; a support holding charged groups and being in the housing; a first electrode and a second electrode in the housing and in contact with the support; and at least one opening in the housing for admitting fluid into the housing.
Claim 2
Dependent Claim
46 words
A fluid sensor comprising: a housing; a support holding charged groups and being in the housing; a first electrode and a second electrode in the housing and in contact with the support; and at least one opening in the housing for admitting fluid into the housing.
Claim 3
Dependent Claim
17 words
The fluid sensor of claim 1, wherein the support comprises resin beads impregnated with the charged groups.
Claim 4
Dependent Claim
23 words
The fluid sensor of claim 2, further comprising a conductive mesh for holding the beads, wherein the conductive mesh is the first electrode.
Claim 5
Dependent Claim
15 words
The fluid sensor of claim 1, wherein the charged groups include an anion and cations.
Claim 6
Dependent Claim
17 words
The fluid sensor of claim 1, further comprising a drain plug in which the housing is mounted.
Claim 7
Dependent Claim
28 words
The fluid sensor of claim 1, further comprising output circuitry connected between the first and second electrodes for displaying a signal indicative of a voltage between the electrodes.
Claim 8
Dependent Claim
62 words
The fluid sensor of claim 1, further comprising a second fluid sensor including a second support holding charged groups in a second housing, a first and a second electrode in the second housing and in contact with the second support, and a second fluid in the second housing; wherein the second fluid sensor is inside the housing of the first fluid sensor.
Claim 9
Dependent Claim
13 words
The fluid sensor of claim 1, wherein the fluid is a non-polar fluid.
Claim 10
Dependent Claim
14 words
The fluid sensor of claim 1, wherein the fluid is a weakly polar fluid.
Claim 11
Dependent Claim
75 words
A drain plug fluid sensor comprising: a drain plug structure adapted to fitting in a drain hole of a fluid reservoir and defining a passage communicating with the reservoir; a housing extending from the drain plug structure and having an internal cavity connecting to the passage; a support holding charged groups and being in the internal cavity; and a first electrode and a second electrode in the internal cavity and in contact with the support.
Claim 12
Dependent Claim
75 words
A drain plug fluid sensor comprising: a drain plug structure adapted to fitting in a drain hole of a fluid reservoir and defining a passage communicating with the reservoir; a housing extending from the drain plug structure and having an internal cavity connecting to the passage; a support holding charged groups and being in the internal cavity; and a first electrode and a second electrode in the internal cavity and in contact with the support.
Claim 13
Independent Claim
66 words
A method for measuring an electrical characteristic of a non-polar or weakly polar fluid, comprising the steps of: providing an ion-exchange resin material having a plurality of charged groups in clusters and having electro-chemical bridges between the charged groups in each cluster; circulating the non-polar or weakly polar fluid to contact the material; and measuring an electrical characteristic of the material while the fluid is circulating.
Claim 14
Independent Claim
66 words
A method for measuring an electrical characteristic of a non-polar or weakly polar fluid, comprising the steps of: providing an ion-exchange resin material having a plurality of charged groups in clusters and having electro-chemical bridges between the charged groups in each cluster; circulating the non-polar or weakly polar fluid to contact the material; and measuring an electrical characteristic of the material while the fluid is circulating.
Claim 15
Dependent Claim
25 words
The method of claim 11, further comprising the step of conditioning the measured electrical characteristic to provide an indication of a property of the fluid.
Claim 16
Dependent Claim
28 words
The method of claim 11, wherein the fluid is a working fluid in a system, and the step of circulating is during a normal operation of the system.
Claim 17
Dependent Claim
12 words
The method of claim 11, wherein the electrical characteristic is electrical conductivity.
Claim 18
Independent Claim
49 words
A method of determining a quality of a fluid, comprising the steps of: providing an insoluble support holding charged groups; circulating the fluid to contact the support; and measuring a solvating effect on the charged groups of the fluid as a variation in an electrical characteristic of the support.
Claim 19
Independent Claim
49 words
A method of determining a quality of a fluid, comprising the steps of: providing an insoluble support holding charged groups; circulating the fluid to contact the support; and measuring a solvating effect on the charged groups of the fluid as a variation in an electrical characteristic of the support.
Claim 20
Dependent Claim
12 words
The method of claim 15, wherein the fluid is a non-polar fluid.
Claim 21
Dependent Claim
13 words
The method of claim 15, wherein the fluid is a weakly polar fluid.
Claim 22
Dependent Claim
14 words
The method of claim 15, wherein the support is a quantity of resin beads.
Claim 23
Dependent Claim
15 words
The method of claim 18, wherein the resin beads are held within a conductive mesh.
Claim 24
Dependent Claim
27 words
The method of claim 15, wherein the fluid is an operating fluid in a system, and the step of circulating is during normal operation of the system.
Claim 25
Dependent Claim
11 words
The method of claim 15, wherein the electrical characteristic is conductivity.
Claim 26
Dependent Claim
11 words
The method of claim 15, wherein the electrical characteristic is capacitance.
Claim 27
Dependent Claim
57 words
The method of claim 15, further comprising the steps of: providing a second insoluble support holding charged groups; providing a second fluid in contact with the second insoluble support; and measuring a solrating effect on the charged groups of the second fluid due to temperature changes as a variation in an electrical characteristic of the second support.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-07-24 | 1999-01-23 | 1999-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-07-24 | 2003-01-23 | 2003-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-07-24 | 2007-01-23 | 2007-07-25 | $7700.00 | Window Closed / Lapsed |