Patent US4028944A successfully refreshed from Google Patents.
US4028944A
Expired / Lapsed
US
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Device for recording temperature minimums
Assignee: Calspan Corp
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Filing: 1975-10-31
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Granted: 1977-06-14
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Expires: 1995-10-31
Abstract
Abstract A device for recording a drop in temperature below a pre-selected temperature minimum. The device provides a permanent record of the drop in temperature. The device is reuseable.
Inventors
- 👤 Robert Allan Erb
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:09
CPC Classifications
G; G01; G01K; G01K11/00; G01K11/06; Y; Y10; Y10S; Y10S252/00; Y10S252/962
Claims Analysis
Total Claims: 62
Claim 1
Independent Claim
96 words
In a device for determining a drop below a temperature threshold point which includes a container holding a polymer-containing aqueous gel in a continuous phase, the improvement which comprises a dispersed phase in the continuous gel, which gel liquifies from gel to liquid below a first temperature point and is reversible from liquid to gel above a temperature point, the device being thereby capable of detecting a decrease of the temperature below the first temperature point by liquifying and by a change of position of the dispersed phase relative to the gel in the continuous phase.
Claim 2
Dependent Claim
96 words
In a device for determining a drop below a temperature threshold point which includes a container holding a polymer-containing aqueous gel in a continuous phase, the improvement which comprises a dispersed phase in the continuous gel, which gel liquifies from gel to liquid below a first temperature point and is reversible from liquid to gel above a temperature point, the device being thereby capable of detecting a decrease of the temperature below the first temperature point by liquifying and by a change of position of the dispersed phase relative to the gel in the continuous phase.
Claim 3
Dependent Claim
18 words
The device of claim 1 wherein the dispersed phase has a density different from that of the gel.
Claim 4
Dependent Claim
15 words
The device of claim 2 wherein the dispersed phase is less dense than the gel.
Claim 5
Dependent Claim
12 words
The device of claim 3 wherein plastic particles form the dispersed phase.
Claim 6
Dependent Claim
10 words
The device of claim 4 wherein the particles are hollow.
Claim 7
Dependent Claim
13 words
The device of claim 5 wherein the plastic particles are spheroidal in shape.
Claim 8
Dependent Claim
17 words
The device of claim 3 wherein the dispersed phase is a liquid, non-miscible with the liquified gel.
Claim 9
Dependent Claim
15 words
The device of claim 7 wherein the liquid is a mineral oil or a hydrocarbon.
Claim 10
Dependent Claim
12 words
The device of claim 8 wherein the dispersed phase is a solid.
Claim 11
Dependent Claim
17 words
The device of claim 7 wherein the liquid is colored, thereby imparting improved visibility to the system.
Claim 12
Dependent Claim
14 words
The device of claim 2 wherein the dispersed phase is denser than the gel.
Claim 13
Dependent Claim
15 words
The device of claim 11 wherein the solid is a metal or a metal oxide.
Claim 14
Dependent Claim
21 words
The device of claim 12 wherein the metal is one of the following: copper, nickel, iron, aluminum, chromium, or their alloys.
Claim 15
Dependent Claim
12 words
The device of claim 12 wherein the metal oxide is iron oxide.
Claim 16
Dependent Claim
10 words
The device of claim 12 wherein the solid is ferromagnetic.
Claim 17
Dependent Claim
28 words
The device of claim 15 which includes a magnet positioned outside the container, which attracts the ferromagnetic material, thereby facilitating detection of the excursion beyond the threshold temperature.
Claim 18
Dependent Claim
17 words
The device of claim 11 wherein the dispersed phase is a liquid, non-miscible with the liquified gel.
Claim 19
Dependent Claim
17 words
The device of claim 17 wherein the liquid is colored, thereby imparting improved visibility of the system.
Claim 20
Dependent Claim
12 words
The device of claim 17, wherein the liquid is a halo-substituted hydrocarbon.
Claim 21
Dependent Claim
10 words
The device of claim 19 wherein the liquid is tetrachloroethylene.
Claim 22
Dependent Claim
15 words
The device of claim 2 wherein the dispersed phase comprises two materials of different densities.
Claim 23
Dependent Claim
30 words
The device of claim 21 wherein in the dispersed phase of the two materials of different densities, one is of higher and one is of lesser density than the gel.
Claim 24
Dependent Claim
25 words
The device of claim 1 wherein the gel has a transition temperature not lower than about 5° C and not higher than about 80° C.
Claim 25
Dependent Claim
24 words
The device of claim 23 wherein the liquifying temperature of the gel is a temperature point in the range of 15° to 35° C.
Claim 26
Dependent Claim
23 words
The device of claim 23 wherein the transition temperature of the gel is about room temperature, the gel becoming liquid below room temperature.
Claim 27
Dependent Claim
19 words
The device of claim 1 wherein the water in the aqueous phase of the gel is substantially ion free.
Claim 28
Dependent Claim
14 words
The device of claim 1 wherein the aqueous phase of the gel is sterile.
Claim 29
Dependent Claim
22 words
The device of claim 1 wherein the water of the aqueous gel is colored, thereby imparting a color to the continuous phase.
Claim 30
Dependent Claim
10 words
The device of claim 1 wherein the container is transparent.
Claim 31
Dependent Claim
10 words
The device of claim 29 wherein the container is glass.
Claim 32
Dependent Claim
10 words
The device of claim 30 wherein the container is sealed.
Claim 33
Dependent Claim
25 words
The device of claim 1 which comprises a background means to which the device is affixed, thereby facilitating detection of the changes in the device.
Claim 34
Dependent Claim
13 words
The device of claim 1 wherein the polymer is a polyol block copolymer.
Claim 35
Dependent Claim
16 words
The device of claim 33 wherein the polymer is a block copolymer of polyoxyethylene and polyoxypropylene.
Claim 36
Dependent Claim
41 words
The device of claim 34 wherein the polymer has a hydrophobic and a hydrophilic portion, the hydrophobic portion being from about forty to ten percent by weight and the hydrophilic portion being from about sixty to about ninety percent by weight.
Claim 37
Dependent Claim
19 words
The device of claim 35 wherein the polymer has an average molecular weight ranging from about 10,000 to 28,000.
Claim 38
Dependent Claim
49 words
A system for determining a series of temperature thresholds which comprises a plurality of devices defined in claim 1, the gel in each of the several devices having a different liquifying temperature from gel to liquid so that each gel liquifies when the temperature drops below the respective threshold.
Claim 39
Dependent Claim
38 words
The device of claim 1 wherein the transition temperature from gel to liquid is not lower than about 5° C, the device thus being operative in detecting a temperature drop from a temperature upwardly from about 5° C.
Claim 40
Dependent Claim
137 words
In a device for determining a temperature threshold including a container. the improvement which comprises, positioned in the container, a polymer containing an aqueous gel in a continuous phase, and a phase of a different density than the gel positioned within the gel, the gel being an aqueous polymer system which liquifies from gel to liquid below a first temperature point and gels from liquid to gel above a temperature point, the phase positioned in the gel being capable of changing position from its position suspended in the gel to a position where it is not suspended within the gel as the gel has liquified, the device thereby being capable of detecting a decrease of the temperature below the first temperature point by liquifying and by a change of position of the phase relative to the gel.
Claim 41
Dependent Claim
137 words
In a device for determining a temperature threshold including a container. the improvement which comprises, positioned in the container, a polymer containing an aqueous gel in a continuous phase, and a phase of a different density than the gel positioned within the gel, the gel being an aqueous polymer system which liquifies from gel to liquid below a first temperature point and gels from liquid to gel above a temperature point, the phase positioned in the gel being capable of changing position from its position suspended in the gel to a position where it is not suspended within the gel as the gel has liquified, the device thereby being capable of detecting a decrease of the temperature below the first temperature point by liquifying and by a change of position of the phase relative to the gel.
Claim 42
Dependent Claim
13 words
The device of claim 39 wherein the phase is a single gas bubble.
Claim 43
Dependent Claim
28 words
The device of claim 39 wherein the phase positioned in the gel is a solid piece of material which has a density greater than that of the gel.
Claim 44
Dependent Claim
10 words
The system of claim 41 wherein the solid is ferromagnetic.
Claim 45
Independent Claim
95 words
The method of determining a temperature threshold in a device which includes a container holding a polymer in an aqueous gel in a continuous phase and a dispersed phase in the gel, wherein the gel is liquifiable below a first temperature point and is reversible from liquid to gel above a temperature point, which comprises subjecting the device to a temperature below the liquefaction gel-transition temperature, causing the gel to liquify and causing the dispersed phase to change its position relative the gel, thereby registering a decrease of the temperature below the liquefaction gel-transition temperature.
Claim 46
Independent Claim
95 words
The method of determining a temperature threshold in a device which includes a container holding a polymer in an aqueous gel in a continuous phase and a dispersed phase in the gel, wherein the gel is liquifiable below a first temperature point and is reversible from liquid to gel above a temperature point, which comprises subjecting the device to a temperature below the liquefaction gel-transition temperature, causing the gel to liquify and causing the dispersed phase to change its position relative the gel, thereby registering a decrease of the temperature below the liquefaction gel-transition temperature.
Claim 47
Dependent Claim
28 words
The method of claim 43 wherein an excursion of the temperature below the transition temperature causes the dispersed phase to rise above or fall below the liquified gel.
Claim 48
Dependent Claim
27 words
The method of claim 43 which includes subjecting the device to a temperature in the range above the transition temperature in which the liquid becomes a gel.
Claim 49
Dependent Claim
28 words
The method of claim 45 which comprises activating an indicia of the lowering of the temperature when the temperature drops below the transition temperature of gel to liquid.
Claim 50
Dependent Claim
10 words
The method of claim 46 wherein the indicia is visual.
Claim 51
Dependent Claim
10 words
The method of claim 46 wherein the indicia is audible.
Claim 52
Dependent Claim
11 words
The method of claim 46 wherein the indicia is electrically activated.
Claim 53
Dependent Claim
30 words
The process of claim 43 which comprises subjecting the device to agitation to create the non-continuous phase in the continuous gel prior to subjecting the device to the liquefaction temperature.
Claim 54
Dependent Claim
14 words
The method of claim 43 wherein the phase in the gel is a gas.
Claim 55
Dependent Claim
10 words
The method of claim 51 wherein the gas is air.
Claim 56
Dependent Claim
97 words
In a device for determining a drop below a temperature threshold point which includes a container holding a polymer-containing aqueous gel in a continuous phase, the improvement which comprises a dispersed gas phase in the continuous gel, which gel liquifies from gel to liquid below a first temperature point and is reversible from liquid to gel above a temperature point, the device being thereby capable of detecting a decrease of the temperature below the first temperature point by liquifying and by change of position of the dispersed gas phase relative to the gel in the continuous phase.
Claim 57
Dependent Claim
97 words
In a device for determining a drop below a temperature threshold point which includes a container holding a polymer-containing aqueous gel in a continuous phase, the improvement which comprises a dispersed gas phase in the continuous gel, which gel liquifies from gel to liquid below a first temperature point and is reversible from liquid to gel above a temperature point, the device being thereby capable of detecting a decrease of the temperature below the first temperature point by liquifying and by change of position of the dispersed gas phase relative to the gel in the continuous phase.
Claim 58
Dependent Claim
11 words
The device of claim 53 wherein the gas phase is air.
Claim 59
Dependent Claim
11 words
The device of claim 54 wherein the gas is air bubbles.
Claim 60
Dependent Claim
11 words
The device of claim 55 wherein the air bubbles are small.
Claim 61
Dependent Claim
38 words
The device of claim 53 wherein the transition temperature from gel to liquid is not lower than about 5° C, the device thus being operative in detecting a temperature drop from a temperature upwardly from about 5° C.
Claim 62
Dependent Claim
48 words
A system for determining a series of temperature thresholds which comprises a plurality of devices defined in claim 53, the gel in each of several devices having a different liquifying temperature from gel to liquid, so that each gel liquifies when the temperature drops below the respective threshold.
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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) | 1980-06-13 | 1980-12-13 | 1981-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-13 | 1984-12-13 | 1985-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-13 | 1988-12-13 | 1989-06-14 | $7700.00 | Window Closed / Lapsed |