Patent US4531087A successfully refreshed from Google Patents.
US4531087A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical sensor for measuring moisture in landscape and agricultural soils
Assignee: Individual
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Filing: 1982-06-09
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Granted: 1985-07-23
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Expires: 2002-06-09
Abstract
Abstract An improved electrical conductance soil moisture sensor for landscape and agriculture comprising electrodes imbedded in a granular medium that is separated from the soil to be measured by a layer of filter cloth supported by a plastic or metal screen.
Inventors
- 👤 Glenn F. Larson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:18
CPC Classifications
A; A01; A01G; A01G25/00; A01G25/16; A01G25/167; G; G01; G01R; G01R27/00; G01R27/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
74 words
An electrical conductivity sensor for the measurement of moisture in a soil medium comprising: a granulous porous medium; at least two electrodes imbedded in said granulous medium; a layer of filter cloth surrounding said porous medium for separating it from said soil medium; a rigid support structure holding said filter cloth in place around said granulous porous medium and allowing a free exchange of moisture between said soil medium and said granulous porous medium.
Claim 2
Dependent Claim
74 words
An electrical conductivity sensor for the measurement of moisture in a soil medium comprising: a granulous porous medium; at least two electrodes imbedded in said granulous medium; a layer of filter cloth surrounding said porous medium for separating it from said soil medium; a rigid support structure holding said filter cloth in place around said granulous porous medium and allowing a free exchange of moisture between said soil medium and said granulous porous medium.
References Cited (Backward Citations)
US2768028A
Cited
GB922225A
Cited
US3412325A
Cited
US3376501A
Cited
GB1387201A
Cited
GB1419235A
Cited
US4137931A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-07-22 | 1989-01-21 | 1989-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-22 | 1993-01-21 | 1993-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-22 | 1997-01-21 | 1997-07-23 | $7700.00 | Window Closed / Lapsed |