US3893340A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermally insulated thermometer
Assignee: Rpr Inc
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Filing: 1973-06-27
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Granted: 1975-07-08
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Expires: 1993-06-27
Abstract
Abstract A thermometer comprising a temperature indicator and a thermally coupled insulator for contacting the object the temperature of which is to be measured. At the thermal interface between the insulator and the temperature indicator the temperature is less (or more) than the object temperature by a factor which is a function of the thermal conductivity and the still convection coefficients of the insulator as well as the ambient temperature. This permits an accurate determination of the object temperature with temperature indicating devices that have a destruct temperature that is lower (or higher) than the object temperature. The temperature indicator is preferably a liquid crystal thermometer having microencapsulated temperature responsive liquid crystal compositions thermally coupled to the insulator. Masking is preferably provided to generate visual displays of messages, common numerical indicia, etc., when the liquid crystals reach their responsive temperature range. The liquid crystals are applied in thin films of a thickness of no more than a few thousandths of an inch so that an accurate determination of the surface temperature on the object is possible.
Inventors
- 👤 Robert Parker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:32
CPC Classifications
G; G01; G01K; G01K3/00; G01K1/00; G01K1/14; G01K1/143; G01K11/00; G01K11/12; G01K11/16; G01K11/165
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
95 words
Apparatus for measuring relatively extreme temperatures comprising an insulator having a first surface for attachment to an object the temperature of which is to be measured and a second surface opposite and spaced apart from the first surface, the insulator having a known and constant thermal conductivity coefficient and a constant still convection coefficient so that the temperature at the second surface is a linear function of the temperature of the object, liquid crystal a thermometer thermally coupled to the second surface, and means cooperating with the thermometer for indicating the temperature of the object.
Claim 2
Dependent Claim
95 words
Apparatus for measuring relatively extreme temperatures comprising an insulator having a first surface for attachment to an object the temperature of which is to be measured and a second surface opposite and spaced apart from the first surface, the insulator having a known and constant thermal conductivity coefficient and a constant still convection coefficient so that the temperature at the second surface is a linear function of the temperature of the object, liquid crystal a thermometer thermally coupled to the second surface, and means cooperating with the thermometer for indicating the temperature of the object.
Claim 3
Dependent Claim
16 words
Apparatus according to claim 1 wherein the crystals are applied to a surface of the insulator.
Claim 4
Dependent Claim
166 words
Apparatus for measuring the temperature on the surface of an object with liquid crystals and in which the object surface temperature is within a known range and in the destruct temperature range for the liquid crystals, the apparatus comprising; a layer of a thermally insulating material having parallel first and second surfaces for affixing the first surface to the object, the material having a constant thermal conductivity coefficient so that the temperature on the second surface is lower than and a linear functin of the temperature on the first surface and a liquid crystal thermometer means thermally interfaced with the second surface of the insulator and having at least one liquid crystal composition, the liquid crystal composition being responsive to a temperature range which is less thAn the temperature at the surface of the object and having a known destruct temperature, the insulator further having a sufficient thickness so that the temperature at the second surface is always outside the destruct temperature range of the composition.
Claim 5
Dependent Claim
166 words
Apparatus for measuring the temperature on the surface of an object with liquid crystals and in which the object surface temperature is within a known range and in the destruct temperature range for the liquid crystals, the apparatus comprising; a layer of a thermally insulating material having parallel first and second surfaces for affixing the first surface to the object, the material having a constant thermal conductivity coefficient so that the temperature on the second surface is lower than and a linear functin of the temperature on the first surface and a liquid crystal thermometer means thermally interfaced with the second surface of the insulator and having at least one liquid crystal composition, the liquid crystal composition being responsive to a temperature range which is less thAn the temperature at the surface of the object and having a known destruct temperature, the insulator further having a sufficient thickness so that the temperature at the second surface is always outside the destruct temperature range of the composition.
Claim 6
Dependent Claim
26 words
Apparatus according to claim 3 including means cooperating with the liquid crystal composition for visually displaying a message indicative of the temperature at the object surface.
Claim 7
Dependent Claim
71 words
Apparatus according to claim 4 wherein the thermometer means comprises a transparent substrate, wherein the liquid crystal composition is between the second surface and the substrate, and wherein the displaying means comprises means masking a portion of the liquid crystal composition from viewing through the substrate so that a remainder of the liquid crystal composition becomes visible through the substrate in said responsive temperature range to thereby visually indicate a message.
Claim 8
Dependent Claim
25 words
Apparatus according to claim 5 wherein the masking defines a written message which becomes visible when the liquid crystal composition is in said temperature range.
Claim 9
Dependent Claim
11 words
Apparatus according to claim 5 wherein the message defines a number
Claim 10
Dependent Claim
29 words
Apparatus according to claim 3 wherein the liquid crystal composition has a destruct temperature of less than about 90* C, and wherein the insulating material has a thickness x
Claim 11
Dependent Claim
51 words
Apparatus according to claim 3 wherein the thermometer means comprise a substrate overlying the second surface, wherein the composition is applied to the substrate, and including means biasing the substrate towards the insulating material to thereby bias the composition against the second surface and thermally couple it with the insulating material.
Claim 12
Dependent Claim
77 words
A liquid crystal thermometer capable of measuring and communicating temperatures of an object in excess of the destruct temperature range for the liquid crystal comprising at least one liquid crystal composition responsive to a known temperature range, means for displaying a message when the composition reaches the known temperature range, a double-faced insulator of a constant thickness, a first face being thermally coupled with the composition and a second face being for attachment to the object, wherein
Claim 13
Dependent Claim
77 words
A liquid crystal thermometer capable of measuring and communicating temperatures of an object in excess of the destruct temperature range for the liquid crystal comprising at least one liquid crystal composition responsive to a known temperature range, means for displaying a message when the composition reaches the known temperature range, a double-faced insulator of a constant thickness, a first face being thermally coupled with the composition and a second face being for attachment to the object, wherein
Claim 14
Dependent Claim
15 words
Apparatus according to claim 10 wherein the displaying means indicates the temperature T1 in degrees.
Claim 15
Dependent Claim
15 words
Apparatus according to claim 11 wherein the display means comprises masking means defining the number
Claim 16
Dependent Claim
29 words
Apparatus according to claim 10 including means for protecting the composition, wherein the displaying means comprises masking means, and wherein the masking means is applied to the protecting means.
Claim 17
Dependent Claim
35 words
Apparatus according to claim 13 wherein the composition is affixed to the protecting means, and including means for biasing the protecting means toward the first face to thereby thermally couple the composition and the insulator.
Claim 18
Independent Claim
134 words
A method for measuring the temperature on the surface on an object with a liquid crystal type thermometer and wherein the object surface temperature can range beyond the destruct temperature of the liquid crystals, the method comprising the steps of thermally coupling an insulator having a uniform thickness to the object surface, the insulator having a sufficient thickness so that the temperature at its exposed side is within the operative temperature range for the liquid crystal when the object surface temperature is in the destruct temperature range for the crystals, applying at least one liquid crystal film having a thickness in the order of a few thousandths of an inch to the exposed insulator side, and identifying a temperature response in the composition as resulting from a given, different temperature at the object surface.
Claim 19
Independent Claim
134 words
A method for measuring the temperature on the surface on an object with a liquid crystal type thermometer and wherein the object surface temperature can range beyond the destruct temperature of the liquid crystals, the method comprising the steps of thermally coupling an insulator having a uniform thickness to the object surface, the insulator having a sufficient thickness so that the temperature at its exposed side is within the operative temperature range for the liquid crystal when the object surface temperature is in the destruct temperature range for the crystals, applying at least one liquid crystal film having a thickness in the order of a few thousandths of an inch to the exposed insulator side, and identifying a temperature response in the composition as resulting from a given, different temperature at the object surface.
Claim 20
Dependent Claim
28 words
A method according to claim 15 wherein the step of identifying comprises the step of displaying a written message activated by a response in the liquid crystal composition.
Claim 21
Dependent Claim
18 words
A method according to claim 16 wherein the step of displaying comprises the step of displaying a number
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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) | 1978-07-07 | 1979-01-06 | 1979-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-07 | 1983-01-06 | 1983-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-07 | 1987-01-06 | 1987-07-08 | $7700.00 | Window Closed / Lapsed |