US6632534B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Encased time domain reflectometry probe
Assignee: Soilmoisture Equipment Corp
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Filing: 2001-08-30
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Granted: 2003-10-14
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Expires: 2021-08-30
Abstract
Abstract A probe adapted for use with a time domain reflectrometry device in primarily measuring the moisture content in soils and other mediums. This probe can however be used in may differing measurement applications involving materials of specific dielectric constants as well as apparent dielectric constants that are derived from a matrix of several differing dielectrics. In the probe according to the present invention, the inner core of the probe is composed of an inner conductive element, a conductor that is used to transmit a broadband pulse. A dielectric liquid, solid or gel surrounds this inner conductive core, and assists in retaining broadband signal strength. The dielectric material is then encased in a metallic outer shell that serves as a protective housing for the probe. This outer shell is electronically transparent to the electromagnetic pulse transmitted by the active inner conductive core and surrounding dielectric. The outer shell is preferably made of stainless steel, but can be made of other materials as they serve to protect the inner dielectric material and conductive core. This combination of features allows a broadband pulse transmitted through the probe to penetrate into the material being measured, returning a much larger reflection feature upon reaching probe end points, while protecting the dielectric-coated transmission elements inside.
Inventors
- 👤 Whitney Skaling
- 👤 Laszlo Rudolics
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:25
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/24; G01N33/246; G01N27/00; G01N27/02; G01N27/22; G01N27/223; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31507; Y10T428/31511; Y10T428/31515; Y10T428/31522; Y10T428/31725
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
39 words
A time domain reflectometry probe for measuring the dielectric properties of a material, comprising: a center conductor, a dielectric material encasing said center conductor; and an outer conductive protective shell encasing both said center conductor and said dielectric material.
Claim 2
Dependent Claim
39 words
A time domain reflectometry probe for measuring the dielectric properties of a material, comprising: a center conductor, a dielectric material encasing said center conductor; and an outer conductive protective shell encasing both said center conductor and said dielectric material.
Claim 3
Dependent Claim
21 words
The time domain reflectrometry probe of claim 1 wherein said probe is used for determining the moisture content in a material.
Claim 4
Dependent Claim
19 words
The time domain reflectometry probe of claim 1 wherein the outer protective shell is made of one of metal.
Claim 5
Dependent Claim
18 words
The time domain reflectometry probe of claim 1 wherein the outer protective shell is made of stainless steel.
Claim 6
Dependent Claim
42 words
The time domain reflectrometry probe of claim 1 wherein the dielectric material encasing said center conductor is made of at least one of: a gel of low dielectric constant; a liquid of low dielectric constant; and a solid of low dielectric constant.
Claim 7
Dependent Claim
29 words
The time domain reflectometry probe of claim 1 wherein the dielectric material encasing said center conductor is made of at least one of: epoxy; plastic; polycarbonate; nylon; and oil.
Claim 8
Dependent Claim
44 words
The time domain reflectometry probe of claim 1 wherein, said probe is an elongated rod; and wherein, said center conductor, said dielectric material encasing said center conductor and said outer protective shell encasing both said center conductor and said dielectric material are concentrically configured.
Claim 9
Dependent Claim
15 words
The time domain reflectrometry probe of claim 1 wherein said probe has a cone-shaped tip.
Claim 10
Dependent Claim
45 words
The time domain reflectometry probe of claim 1 wherein, said probe is a rectangular plate; and wherein, said center conductor is a rectangular plate, said dielectric material encases said center conductor and said outer protective shell encases both said center conductor and said dielectric material.
Claim 11
Dependent Claim
30 words
The time domain reflectometry probe of claim 9 wherein a pair of said probes is positioned parallel to each other such that a material to be measured flows between them.
Claim 12
Dependent Claim
62 words
The time domain reflectometry probe of claim 9 wherein a pair of said probes are positioned such that a material to be measured flows between them and that they are closer to each other at one end than the other such that the density of a material flowing between them is made more consistent so that more repeatable measurements can be taken.
Claim 13
Dependent Claim
45 words
The time domain reflectometry probe of claim 1 wherein, said probe is a circular plate; and wherein, said center conductor is a circular plate, said dielectric material encases said center conductor and said outer protective shell encases both said center conductor and said dielectric material.
Claim 14
Dependent Claim
45 words
The time domain reflectometry probe of claim 1 wherein, said probe is a triangular plate; and wherein, said center conductor is a triangular plate, said dielectric material encases said center conductor and said outer protective shell encases both said center conductor and said dielectric material.
Claim 15
Dependent Claim
45 words
The time domain reflectometry probe of claim 1 wherein, said probe is rod-shaped, and wherein said center conductor is coil-shaped; and wherein said center conductor is potted in a dielectric material; and wherein said outer protective shell encases said center conductor and said dielectric material.
Claim 16
Dependent Claim
60 words
The time domain reflectometry probe of claim 1 wherein, said probe is disc-shaped having an annular hole through the center of the disc, and wherein said center conductor said center conductor is a disc-shaped plate with an annular hole, said dielectric material encases said center conductor and said outer protective shell encases both said center conductor and said dielectric material.
Claim 17
Dependent Claim
16 words
The time domain reflectometry probe of claim 15 wherein said probe is mounted to a vehicle.
Claim 18
Dependent Claim
52 words
The time domain reflectometry probe of claim 1 wherein, said probe is a rectangular plate; and wherein said center conductor that snakes through the center of said rectangular plate; and wherein said dielectric material encases said center conductor and said outer protective shell encases both said center conductor and said dielectric material.
Claim 19
Dependent Claim
62 words
The time domain reflectometry probe of claim 17 wherein a pair of said probes are positioned such that a material to be measured flows between them and that they are closer to each other at one end than the other such that the density of a material flowing between them is made more consistent so that more repeatable measurements can be taken.
Claim 20
Dependent Claim
80 words
A pair of time domain reflectometry probes for measuring the dielectric properties of a material, comprising: a first rod-shaped probe, comprising a center conductor, a dielectric material encasing said center conductor; and an outer protective shell encasing both said center conductor and said dielectric material; and a second ring-shaped probe concentrically-located around said first probe, comprising: a center conductor, a dielectric material encasing said center conductor; and an outer protective shell encasing both said center conductor and said dielectric material.
Claim 21
Dependent Claim
80 words
A pair of time domain reflectometry probes for measuring the dielectric properties of a material, comprising: a first rod-shaped probe, comprising a center conductor, a dielectric material encasing said center conductor; and an outer protective shell encasing both said center conductor and said dielectric material; and a second ring-shaped probe concentrically-located around said first probe, comprising: a center conductor, a dielectric material encasing said center conductor; and an outer protective shell encasing both said center conductor and said dielectric material.
Claim 22
Dependent Claim
34 words
A probe for measuring the properties of a material, comprising: a center conductor, a dielectric material encasing said center conductor; and an outer protective shell encasing both said center conductor and said dielectric material.
Claim 23
Dependent Claim
34 words
A probe for measuring the properties of a material, comprising: a center conductor, a dielectric material encasing said center conductor; and an outer protective shell encasing both said center conductor and said dielectric material.
Claim 24
Dependent Claim
80 words
The probe of claim 19 wherein the probe is used in the measurement of at least one of: (a) determination of concentrations of particles suspended in water and other liquids; (b) determination of the amount of air entrapped in liquids, slurries and gels; (c) determination of the liquid levels of immiscible fluids having differing dielectric character; (d) determination of the proportional content in differing dielectrics soluble in water; (d) and determination of the bulk content of the material being measured.
Claim 25
Independent Claim
187 words
A method for using a time domain reflectometry probe assembly to measure the moisture content in a medium, comprising: inserting a pair of probes of known length into a medium to be measured, wherein each probe comprises: a center conductor, a dielectric material encasing said center conductor; and an outer protective shell encasing both said center conductor and said dielectric material; connecting a coaxial cable to the pair of probes; transmitting a signal of the kind used in time domain reflectometry through the coaxial cable and the probes; introducing a detectable characteristic reference reflection into the signal by way of a specific construction-imposed impedance mismatch between the coaxial cable and the probes independent of the impedance of the medium being measured which causes an identifiable reference reflection in the signal transmitted through the probes in order to mark a known location in relation to the probes; commencing a measurement of time delay in response to detection of the characteristic reference reflection; calculating an apparent dielectric constant value based on the time delay; and correlating the apparent dielectric constant with data reflecting the moisture content of the medium.
Claim 26
Independent Claim
187 words
A method for using a time domain reflectometry probe assembly to measure the moisture content in a medium, comprising: inserting a pair of probes of known length into a medium to be measured, wherein each probe comprises: a center conductor, a dielectric material encasing said center conductor; and an outer protective shell encasing both said center conductor and said dielectric material; connecting a coaxial cable to the pair of probes; transmitting a signal of the kind used in time domain reflectometry through the coaxial cable and the probes; introducing a detectable characteristic reference reflection into the signal by way of a specific construction-imposed impedance mismatch between the coaxial cable and the probes independent of the impedance of the medium being measured which causes an identifiable reference reflection in the signal transmitted through the probes in order to mark a known location in relation to the probes; commencing a measurement of time delay in response to detection of the characteristic reference reflection; calculating an apparent dielectric constant value based on the time delay; and correlating the apparent dielectric constant with data reflecting the moisture content of the medium.
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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) | 2006-10-13 | 2007-04-14 | 2007-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-10-13 | 2011-04-14 | 2011-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-10-13 | 2015-04-14 | 2015-10-14 | $7700.00 | Window Closed / Lapsed |