Patent US4378637A successfully refreshed from Google Patents.
Patent US5121630A successfully refreshed from Google Patents.
US5121630A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Material monitoring device
Assignee: Individual
•
Filing: 1990-12-21
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Granted: 1992-06-16
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Expires: 2010-12-21
Abstract
Abstract The present invention is directed to devices for detecting the moisture content of material such as a diaper using a change in bulk dielectric constant. More particularly, the invention relates to a moisture sensing device which provides an accurate indication of the moisture content of a material such as a diaper when merely placed in the vicinity of the diaper. In a preferred embodiment, the device is a hand-held device which can be readily transported and which can detect diaper moisture without piercing the diaper or attaching electrodes directly to the diaper.
Inventors
- 👤 Noel M. Calvin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 08:11
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/22; G01N27/223
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
67 words
A moisture sensing device for detecting moisture content of a material comprising: a capacitance proximity sensor; and, an indicator responsive to an output of said capacitance proximity sensor, said capacitance proximity sensor further including: a charge pump; and, an antenna formed as a single metal plate for detecting changes in the bulk dielectric constant of a material placed between said metal plate and a variable ground plane.
Claim 2
Dependent Claim
67 words
A moisture sensing device for detecting moisture content of a material comprising: a capacitance proximity sensor; and, an indicator responsive to an output of said capacitance proximity sensor, said capacitance proximity sensor further including: a charge pump; and, an antenna formed as a single metal plate for detecting changes in the bulk dielectric constant of a material placed between said metal plate and a variable ground plane.
Claim 3
Dependent Claim
13 words
Device according to claim 1, wherein said device is a portable, hand-held device.
Claim 4
Dependent Claim
57 words
Device according to claim 1, wherein said capacitance proximity sensor further includes: a square wave generator for providing an input to said charge pump; an integrator and bias circuit for receiving an output from said charge pump and antenna; and, a peak-hold circuit for storing a maximum signal proportional to the bulk dielectric constant of a material.
Claim 5
Dependent Claim
13 words
Device according to claim 1, wherein said indicator is a liquid crystal display.
Claim 6
Dependent Claim
13 words
Device according to claim 1, wherein said indicator is a multi-colored LED display.
Claim 7
Dependent Claim
24 words
Device according to claim 1, wherein said indicator is a light generator which flashes at a rate proportional to the degree of moisture sensed.
Claim 8
Dependent Claim
30 words
Device according to claim 1, wherein said indicator is a tone generator having a tone which is adjusted in proportion to the degree of moisture detected b said sensing device.
Claim 9
Dependent Claim
112 words
A portable, hand-held moisture sensing device for detecting moisture content of a material comprising: a capacitance proximity sensor; and, a liquid crystal display indicator responsive to an output of said capacitance proximity sensor, said capacitance proximity sensor further including: a charge pump; an antenna formed as a single metal plate for detecting changes in the bulk dielectric constant between said metal plate and a variable ground plane; a square wave generator for providing an input to said charge pump; an integrator and bias circuit for receiving an output from said charge pump and antenna; and, a peak-hold circuit for storing a maximum signal proportional to the bulk dielectric constant of a material.
Claim 10
Dependent Claim
112 words
A portable, hand-held moisture sensing device for detecting moisture content of a material comprising: a capacitance proximity sensor; and, a liquid crystal display indicator responsive to an output of said capacitance proximity sensor, said capacitance proximity sensor further including: a charge pump; an antenna formed as a single metal plate for detecting changes in the bulk dielectric constant between said metal plate and a variable ground plane; a square wave generator for providing an input to said charge pump; an integrator and bias circuit for receiving an output from said charge pump and antenna; and, a peak-hold circuit for storing a maximum signal proportional to the bulk dielectric constant of a material.
Claim 11
Dependent Claim
25 words
Device according to claim 8, wherein said antenna is a first electrode of a capacitor for storing a voltage relative to an earth ground plane.
Claim 12
Dependent Claim
25 words
Device according to claim 1, wherein said antenna is a first electrode of a capacitor for storing a voltage relative to an earth ground plane.
Claim 13
Dependent Claim
22 words
Device according to claim 3, wherein said square wave generator produces a square wave to measure change accumulated on said metal plate.
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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) | 1995-06-16 | 1995-12-16 | 1996-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-06-16 | 1999-12-16 | 2000-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-06-16 | 2003-12-16 | 2004-06-16 | $7700.00 | Window Closed / Lapsed |