Patent US4939102A successfully refreshed from Google Patents.
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US4052901A
Expired / Lapsed
US
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Level detecting
Assignee: Individual
•
Filing: 1976-07-29
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Granted: 1977-10-11
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Expires: 1996-07-29
Abstract
Abstract Liquid level detection apparatus and other apparatus comprising in common an elongated flexible substrate transducer which can extend into a liquid containing vessel or be applied to other pressure or force measurement tasks and provide an accurate indication of liquid level or other pressure or force related parameter through a voltage drop measurement made through an elongated, e.g., sinuous or other regular pattern (or of irregular patterning to localize areas of highest sensitivity) conductor pattern contained in the transducer which is shorted out in the portion thereof subjected to a predetermined pressure, the elongated conductor being on facing portions of a folded sheet substrate material which has an inherent spring characteristic (resilience) and/or geometrical-arrangement-loading such that the portion thereof subjected to such pressure has butting face portions and the portion thereof not subjected to such pressure is separated due to the spring characteristic of the folded sheet material. For instance, as applied to liquid level measurement, the folded substrate is in elongated ribbon form and the portion below liquid level is subjected to liquid pressure sufficient to move the two facing portions in butting engagement causing elongated conductor patterns thereon to short out at liquid level.
Inventors
- 👤 Albion P. Bjork
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 08:16
CPC Classifications
H; H01; H01C; H01C10/00; H01C10/10; G; G01; G01B; G01B7/00; G01B7/02; G01D; G01D5/00; G01D5/12; G01D5/14; G01D5/16; G01D5/165; G01F; G01F23/00; G01F23/14; G01F23/18; G01F23/30; G01F23/64; G01F23/72
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
229 words
Pressure detection apparatus comprising, a transducer element for immersion in a pressure medium, or a fluent environment or subjection to a like activating force, comprising means defining an extended length of springy lengthwise folded sheet material for extending into the pressure medium with its folded portions contacting each other face to face at portions exposed to a pressure above a predetermined threshold on the backs of said folded portions or other activating force, the springy character of the folded sheet material and geometric loading arrangement holding the folded portions apart in other portions thereof, means defining elongated conductors on opposing front faces of the folded portions comprising a periodic zig-zag waveform conductive path on each facing portion of the folded sheet arranged in complementary form so that the two conductive paths for X intersections to short out the conductive paths by butting contact wherever the facing portions are pressed together, so that the remaining portions of the conductive paths define resistive lengths in a circuit to the extent they are not essentially shorted out of said circuits by butting contact with each other, and means for applying an electric current to the conductors and for measuring a parameter of said circuit as an indication of the pressure or other activating force which presses the portions together, and wherein an insulator sheet with openings is placed between the folded portions.
Claim 2
Dependent Claim
229 words
Pressure detection apparatus comprising, a transducer element for immersion in a pressure medium, or a fluent environment or subjection to a like activating force, comprising means defining an extended length of springy lengthwise folded sheet material for extending into the pressure medium with its folded portions contacting each other face to face at portions exposed to a pressure above a predetermined threshold on the backs of said folded portions or other activating force, the springy character of the folded sheet material and geometric loading arrangement holding the folded portions apart in other portions thereof, means defining elongated conductors on opposing front faces of the folded portions comprising a periodic zig-zag waveform conductive path on each facing portion of the folded sheet arranged in complementary form so that the two conductive paths for X intersections to short out the conductive paths by butting contact wherever the facing portions are pressed together, so that the remaining portions of the conductive paths define resistive lengths in a circuit to the extent they are not essentially shorted out of said circuits by butting contact with each other, and means for applying an electric current to the conductors and for measuring a parameter of said circuit as an indication of the pressure or other activating force which presses the portions together, and wherein an insulator sheet with openings is placed between the folded portions.
Claim 3
Dependent Claim
15 words
Pressure transducer apparatus in accordance with claim 1 wherein the zig-zag form is linearly periodic.
Claim 4
Dependent Claim
15 words
Pressure transducer apparatus in accordance with claim 1 wherein the zig-zag form is non-linearly periodic.
Claim 5
Dependent Claim
42 words
Pressure apparatus in accordance with claim 1 wherein the sheet material is contained in a flexible sealed wrap and the butting contact for shorting out is produced by fluid pressure or other force on the back side of the folded sheet material.
Claim 6
Dependent Claim
30 words
Pressure apparatus in accordance with claim 1 wherein the sheet material is contained in a rigid sheath and the butting contact for shorting out is produced by a supplementary drive.
Claim 7
Dependent Claim
33 words
Pressure apparatus in accordance with claim 5 wherein the supplementary drive is an external magnet movable by the pressure medium or other activating force and coacting with magnetic material within the folded sheet.
Claim 8
Dependent Claim
31 words
Pressure detection apparatus in accordance with claim 1 wherein the openings are in a graded series of size to provide relative measurement such as gauge pressure, hydraulic head or the like.
Claim 9
Dependent Claim
16 words
Pressure detection apparatus in accordance with claim 1 constructed and arranged as a liquid level control.
Claim 10
Dependent Claim
37 words
Pressure detection apparatus in accordance with claim 8 in combination with a liquid container and means for suspending the said transducer element substantially vertically along its folded length with the shorted out portions defining liquid level height.
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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) | 1980-10-10 | 1981-04-11 | 1981-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-10 | 1985-04-11 | 1985-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-10 | 1989-04-11 | 1989-10-11 | $7700.00 | Window Closed / Lapsed |