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US4503384A Expired / Lapsed US ⏱️ 0.0 years remaining

Microwave probe for measurement of dielectric constants

Assignee: Motors Liquidation Co
•
Filing: 1982-04-28
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Granted: 1985-03-05
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Expires: 2002-04-28
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Abstract

Abstract A microwave probe for measuring the amount of soot or water in engine crankcase oil and/or detecting the level of oil comprises a coaxial cable having a tip including five substantially parallel wires shorted together at one end and connected at the other end to the coaxial cable, one of the wires being connected to the center wire of the coaxial cable and the other four wires being connected to the sheath of the coaxial cable. The size and geometry of the wires is selected so that the impedance of the tip when immersed in oil substantially matches the impedance of the coaxial cable.

Inventors

  • 👤 Louis L. Nagy
  • 👤 Michael J. O'Rourke

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 23:35
CPC Classifications
G; G01; G01R; G01R27/00; G01R27/02; G01R27/26; G01R27/2617; G01R27/2635; G01R27/2676; G01F; G01F23/00; G01F23/22; G01F23/28; G01F23/284; G01N; G01N22/00; G01R27/04

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 27 words
A microwave probe for measuring the dielectric constant of a liquid comprising: a coaxial cable having an outer conductive sheath and a concentrically located inner wire, and
Claim 2
Dependent Claim 27 words
A microwave probe for measuring the dielectric constant of a liquid comprising: a coaxial cable having an outer conductive sheath and a concentrically located inner wire, and
Claim 3
Dependent Claim 98 words
a cage-like tip attached to an end of the coaxial cable including a center wire connected to the said inner wire, a three to five outer wires each connected at one end to the sheath and surrounding the center wire, the outer wires being spaced sufficiently to facilitate free flow of liquid through the tip, and means shorting the distal ends of the said center wire and outer wires; the wire geometry and number of wires being so selected that the impedance of the tip, when immersed in the liquid, substantially matches the impedance of the coaxial cable.
Claim 4
Dependent Claim 98 words
a cage-like tip attached to an end of the coaxial cable including a center wire connected to the said inner wire, a three to five outer wires each connected at one end to the sheath and surrounding the center wire, the outer wires being spaced sufficiently to facilitate free flow of liquid through the tip, and means shorting the distal ends of the said center wire and outer wires; the wire geometry and number of wires being so selected that the impedance of the tip, when immersed in the liquid, substantially matches the impedance of the coaxial cable.
Claim 5
Dependent Claim 127 words
A microwave probe for measuring the dielectric constant of a liquid comprising: a coaxial cable having an outer conductive sheath and a concentrically located inner wire; and a cage-like tip attached to an end of the coaxial cable consisting of five parallel wires shorted at one end including a center wire connected to the said inner wire, four outer wires each connected at one end to the sheath and surrounding the center wire, the outer wires being spaced sufficiently to facilitate free flow of liquid through the tip, and a shorting conductor connected to the distal ends of the said parallel wires; the wire geometry being so selected that the impedance of the tip, when immersed in the liquid, substantially matches the impedance of the coaxial cable.
Claim 6
Dependent Claim 127 words
A microwave probe for measuring the dielectric constant of a liquid comprising: a coaxial cable having an outer conductive sheath and a concentrically located inner wire; and a cage-like tip attached to an end of the coaxial cable consisting of five parallel wires shorted at one end including a center wire connected to the said inner wire, four outer wires each connected at one end to the sheath and surrounding the center wire, the outer wires being spaced sufficiently to facilitate free flow of liquid through the tip, and a shorting conductor connected to the distal ends of the said parallel wires; the wire geometry being so selected that the impedance of the tip, when immersed in the liquid, substantially matches the impedance of the coaxial cable.
Claim 7
Dependent Claim 120 words
A microwave probe for measuring the dielectric constant of a liquid comprising: a coaxial cable having an outer conductive sheath and a concentrically located inner wire, the inner wire axially extending a fixed distance beyond the sheath; a round conductor element having a diameter approximately the same as the sheath diameter connected to the end of the inner wire, and four outer wires parallel to the inner wire connected between the conductor element and the sheath to form a cage-like tip with sufficient space between the wires to allow free fluid flow through the tip, the wire geometry being so selected that the impedance of the tip, when immersed in the liquid, substantially matches the impedance of the coaxial cable.
Claim 8
Dependent Claim 120 words
A microwave probe for measuring the dielectric constant of a liquid comprising: a coaxial cable having an outer conductive sheath and a concentrically located inner wire, the inner wire axially extending a fixed distance beyond the sheath; a round conductor element having a diameter approximately the same as the sheath diameter connected to the end of the inner wire, and four outer wires parallel to the inner wire connected between the conductor element and the sheath to form a cage-like tip with sufficient space between the wires to allow free fluid flow through the tip, the wire geometry being so selected that the impedance of the tip, when immersed in the liquid, substantially matches the impedance of the coaxial cable.

References Cited (Backward Citations)

US3226615A Cited
US3572119A Cited
US3626284A Cited
US3703829A Cited
US3812422A Cited
US4345202A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-03-04 1988-09-03 1989-03-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-03-04 1992-09-03 1993-03-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-03-04 1996-09-03 1997-03-05 $7700.00 Window Closed / Lapsed

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