Wireless Temperature Sensor Having No Electrical Connections and Sensing Method for Use Therewith

• US 20140269825A1
• Filed: 02/28/2014
• Published: 09/18/2014
• Est. Priority Date: 02/17/2010
• Status: Active Grant

• Current Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Original Assignee: U.S.A. as represented by the Administrator of the National Aeronautics and Space Administration
• Inventors: Woodard, Stanley E., Taylor, Bryant D., Wang, Chuantong
• Granted Patent: US 10,031,031 B2
• Time in Patent Office: Days
• US Class Current: 374/120
• CPC Class Codes: G01K 7/00 Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat giving results other than momentary value of temperature G01K3/00 ; Power supply therefor, e.g. using thermoelectric elements
• CPC Class Codes: G01K 7/38 the variations of temperature influencing the magnetic permeability

Abstract

A wireless temperature sensor includes an electrical conductor and a material spaced apart from the conductor and located within one or more of the responding electric field and responding magnetic field of the conductor. The conductor is electrically unconnected and is shaped for storage of an electric field and a magnetic field. In the presence of a time-varying magnetic field, the conductor resonates to generate harmonic electric and magnetic field responses, each of which has a frequency associated therewith. The material is selected such that it experiences changes in one of dielectric properties and magnetic permeability properties in the presence of a temperature change. Shifts from the sensor'"'"'s baseline frequency response indicate that the material has experienced a temperature change.

Claims

1. A wireless temperature sensor, comprising:

an electrical conductor having first and second ends and shaped between said first and second ends for storage of an electric field and a magnetic field, said first and second ends remaining electrically unconnected such that said electrical conductor so-shaped defines an unconnected open-circuit having inductance and capacitance wherein, in the presence of a time-varying magnetic field, said electrical conductor so-shaped resonates to generate harmonic electric and magnetic field responses, each of which has a frequency associated therewith; and

a solid material spaced apart from said conductor and located within one or more of the responding electric field and responding magnetic field of said conductor, said material selected to experience changes in one of dielectric properties and magnetic permeability properties in the presence of a temperature change.

2. A wireless temperature sensor as in claim 1, further comprising a magnetic field response recorder for wirelessly transmitting said time-varying magnetic field to said electrical conductor and for wirelessly detecting said frequency associated with said magnetic field response so-generated and resulting from said changes.

3. A wireless temperature sensor as in claim 1, further comprising an electric field response recorder for wirelessly transmitting said time-varying magnetic field to said electrical conductor and for wirelessly detecting said frequency associated with said electric field response so-generated and resulting from a current state of said dielectric attributes.

4. A wireless temperature sensor as in claim 1, wherein said electrical conductor comprises a thin-film trace.

5. A wireless temperature sensor as in claim 1, wherein said material comprises a dielectric material selected from the group consisting of piezoceramics and glass.

6. A wireless temperature sensor as in claim 1, wherein said material comprises a magnetic material selected from the group consisting of manganese copper, nickel zinc and manganese zinc.

7. A wireless temperature sensor as in claim 1, wherein said electrical conductor and said solid material are flexible.

16. A wireless temperature sensor as in claim 1, further comprising an electrically insulating barrier spaced apart from and between said electrical conductor and said solid material.

8. A wireless temperature sensor, comprising:

an electrically-insulating substrate;

an open-circuit pattern of electrically-conductive material on a face of said substrate, said pattern having two electrically unconnected ends, said pattern shaped for storage of an electric field and a magnetic field, said pattern having inductance and capacitance that allows said pattern to generate harmonic electric and magnetic field responses when in the presence of a time-varying magnetic field, each of said electric and magnetic field responses having a frequency associated therewith; and

a solid material spaced apart from said conductor and located within one or more of the responding electric field and responding magnetic field of said conductor, said material selected to experience changes in one of dielectric properties and magnetic permeability properties in the presence of a temperature change.

9. A wireless temperature sensor as in claim 8, further comprising a magnetic field response recorder for wirelessly transmitting said time-varying magnetic field to said pattern and for wirelessly detecting said frequency associated with said magnetic field response so-generated and resulting from said changes.

10. A wireless temperature sensor as in claim 8, further comprising an electric field response recorder for wirelessly transmitting said time-varying magnetic field to said pattern and for wirelessly detecting said frequency associated with said electric field response so-generated and resulting from said changes.

11. A wireless temperature sensor as in claim 8, wherein said substrate is flexible.

12. A wireless temperature sensor as in claim 8, wherein said first face is planar and wherein said pattern is a spiral trace.

13. A wireless temperature sensor as in claim 8, wherein said material comprises a dielectric material selected from the group consisting of piezoceramics and glass.

14. A wireless temperature sensor as in claim 8, wherein said material comprises a magnetic material selected from the group consisting of manganese copper, nickel zinc and manganese zinc.

15. A wireless temperature sensor as in claim 8, wherein said electrical conductor and said solid material are flexible.

17. A wireless temperature sensor as in claim 8, further comprising an electrically insulating barrier spaced apart from and between said electrical conductor and said solid material.

18. A method of sensing temperature, comprising the steps of:

providing an electrical conductor having first and second ends and shaped between said first and second ends for storage of an electric field and a magnetic field, said first and second ends remaining electrically unconnected such that said electrical conductor so-shaped defines an unconnected open-circuit having inductance and capacitance wherein, in the presence of a time-varying magnetic field, said electrical conductor so-shaped resonates to generate harmonic electric and magnetic field responses, each of which has a frequency associated therewith;

providing a solid material spaced apart from said conductor and located within one or more of the responding electric field and responding magnetic field of said conductor, said material selected to experience changes in one of dielectric properties and magnetic permeability properties in the presence of a temperature change;

recording a baseline frequency response for said at least one of said electric and magnetic field responses so-generated when temperature is not changing; and

monitoring said at least one of said electric and magnetic field responses so-generated for changes in frequency with respect to said baseline frequency response as an indication of a change in temperature.