Thermal sensor

Patent metadata

Field	Value
Publication number	US-9518872-B2
Application number	US-201414514248-A
Country	US
Kind code	B2
Filing date	Oct 14, 2014
Priority date	Oct 14, 2014
Publication date	Dec 13, 2016
Grant date	Dec 13, 2016

Abstract

A thermal sensor includes a first electrode, a second electrode, and a plurality of beads disposed between the first electrode and the second electrode, the beads defining bead cavities between each other. A method for manufacturing a thermal sensor includes disposing a plurality of beads on an inner electrode, dip coating the inner electrode with beads using a molten state changing material, and disposing an outer electrode over the inner electrode and beads after dip coating.

First claim

What is claimed is:

1. A thermal sensor, comprising:
a first electrode;
a second electrode; and
a plurality of beads disposed between the first electrode and the second electrode, the beads defining bead cavities between each other; and a state changing material disposed in the bead cavities, wherein the state changing material transitions between a non-conductive state to a conductive state at a threshold temperature, wherein, in the conductive state, the state change material electrically connects the first and second electrodes.

2. The thermal sensor of claim 1 , wherein the first and second electrodes are coaxial electrodes.

3. The thermal sensor of claim 1 , wherein the first and second electrodes include aluminum or Inconel 625.

4. The thermal sensor of claim 1 , wherein the beads can include at least one of a ceramic or a high temperature polymer.

5. The thermal sensor of claim 1 , wherein the beads includes at least one of a glass fiber, polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), polyetherimide (PEI), polyphenylsulfone (PPSU), or polysulfone (PSU).

6. The thermal sensor of claim 1 , wherein the beads are porous for absorbing the state change material.

7. The thermal sensor of claim 1 , wherein the state changing material includes a salt mixture.

8. The thermal sensor of claim 7 , wherein the salt mixture is a eutectic salt mixture.

9. A method for manufacturing a thermal sensor, comprising:
disposing a plurality of beads on an inner electrode;
dip coating the inner electrode with beads using a molten state changing material; and
disposing an outer electrode over the inner electrode and beads after dip coating.

10. The method of claim 9 , wherein dip coating includes dip coating the beads in a molten or aqueous salt mixture.

11. The method of claim 9 , wherein dip coating includes dip coating the beads in a molten or aqueous eutectic salt mixture.

12. The method of claim 9 , wherein disposing an outer electrode over the inner electrode includes coaxially disposing the outer electrode over the inner electrode.

13. The method of claim 9 , wherein disposing the plurality of beads on the inner electrode includes sliding the beads onto the inner electrode.

14. The method of claim 9 , wherein disposing the plurality of beads on the inner electrode includes forming the beads around the inner electrode.

Assignees

• Kidde Tech Inc

Inventors

• Rogers Aaron S
• Georgoulias Chris G
• Newlin Scott K

Classifications

• B05D1/18

  performed by dipping · CPC title

• G01K7/16 Primary

  using resistive elements · CPC title

• B05D3/12

  by mechanical means · CPC title

• G01K11/06

  using melting, freezing, or softening · CPC title

• G01K3/005 Primary

  Circuits arrangements for indicating a predetermined temperature (fire detection G08B17/00) · CPC title