Extended temperature range thermal variable-resistance device
View Patent ↗A sensor and method of manufacturing an extended temperature range variable resistance sensor that is cost effective and highly reliable, with stable resistance with an operating range of up to 1700° C. in hostile environments. The sensor is formed of highly stable dispersion hardened materials capable of withstanding mechanical loads and chemical attacks at elevated temperatures while maintaining internal chemical integrity. Electronics are implemented to condition the devices output and convert it to an industry standard.
1. A sensor which is resistant to degradation at high temperature; said sensor comprising:
a substrate formed with a thin insulating coating from at least one noble metal and an oxide selected from the group consisting of: yttrium oxide, cerium oxide, zirconium oxide, and combinations of these;
a resistor, disposed on said substrate, formed from at least one noble metal and an oxide selected from the group consisting of yttrium oxide, cerium oxide, zirconium oxide, and combinations of these; and
at least a first and second lead electrically connected to the resistor for transmitting an electrical signal.
2. The sensor of claim 1 wherein said resistor is deposited on said substrate.
3. The sensor of claim 1 wherein said substrate comprises an insulator having a selected resistance value.
4. The sensor of claim 1 , wherein said noble metal of the thin insulating coating associated with said substrate comprises a platinum group metal.
5. The sensor of claim 1 , wherein said noble metal of the thin insulating coating associated with said substrate comprises Pt/Rh.
6. The sensor of claim 1 , wherein said resistor comprises platinum and said oxide associated with said resistor is dispersion hardened within grain boundaries and a main body of the platinum.
7. The sensor of claim 6 , wherein said resistor comprises yttrium oxide and zirconium oxide.
8. The sensor of claim 1 , wherein a varying temperature causes a varying resistance in the resistor.
9. The sensor of claim 8 , wherein an electrical power source is applied to the resistor.
10. The sensor of claim 9 , wherein said power source comprises an electrical current source, which is applied to said resistor for generating an electrical signal.
11. The sensor of claim 10 , wherein said electrical signal comprises a varying voltage that correlates to the varying resistance of the resistor.
12. The sensor of claim 11 , further comprising a transducer and wherein the varying voltage is applied to said transducer.
13. The sensor of claim 12 , further comprising a transducer output that correlates to a temperature.
14. The sensor of claim 13 , wherein said transducer is a temperature measuring device.
15. The sensor of claim 1 , wherein said resistor is adapted as a heat flux sensor.
16. The sensor of claim 1 , wherein said resistor is adapted as a resistance temperature detector for measuring localized temperature.
17. The sensor of claim 1 , further comprising a sheath to house the resistor.
18. The sensor of claim 17 , wherein said sheath further comprises at least one noble metal and an oxide selected from the group consisting of: yttrium oxide, cerium oxide, zirconium oxide, and combinations of these.
19. The sensor of claim 17 , wherein said sheath further comprises an alloy.
20. The sensor of claim 17 , further comprising an insulator for insulating the resistor from the sheath.
21. The sensor of claim 20 , wherein said insulation comprises a refractory material.
22. The sensor of claim 20 , wherein said insulation comprises Al 2 O 3 .
23. The sensor of claim 20 , wherein said insulation comprises MgO.
24. The sensor of claim 1 , adapted to operate up to 1700° C.
25. The sensor of claim 1 further comprising a third lead electrically connected to the resistor, for transmitting an electrical signal.
26. The sensor of claim 25 further comprising a fourth lead electrically connected to the resistor, for transmitting an electrical signal.
27. A sensor which is resistant to degradation at high temperature; said sensor comprising:
a substrate formed with a thin insulating coating from at least one noble metal and an oxide selected from the group consisting of: yttrium oxide, cerium oxide, zirconium oxide, and combinations of these;
a resistor, disposed on said substrate, formed from an oxide selected from the group consisting of yttrium oxide, cerium oxide, zirconium oxide, and combinations of these, said oxide dispersion hardened within the grain boundary of at least one base metal selected from the group consisting of the noble metals and the precious metals, and combination of these; and
at least a first and second lead electrically connected to the resistor for transmitting an electrical signal.
28. The sensor of claim 27 , wherein said base metal comprises a noble metal.
29. The sensor of claim 28 , wherein said base metal comprises a platinum group metal.
30. The sensor of claim 29 , wherein said resistor comprises platinum and said oxide is dispersion hardened within grain boundaries and a main body of the platinum.
31. The sensor of claim 27 , wherein said resistor is a resistance temperature detector adapted to measuring localized temperature.
32. The sensor of claim 27 further comprising a third lead electrically connected to the resistor, for transmitting an electrical signal.
33. The sensor of claim 32 further comprising a fourth lead electrically connected to the resistor, for transmitting an electrical signal.
34. A method for manufacturing a sensor which is resistant to degradation at high temperatures comprising the steps of:
forming a resistor from at least one noble metal and an oxide selected from the group consisting of yttrium oxide, cerium oxide, zirconium oxide, and combinations of these;
providing a substrate;
depositing a thin insulating coating on the substrate of at least one noble metal and an oxide selected from the group consisting of yttrium oxide, cerium oxide, zirconium oxide, and combinations of these;
depositing said resistor on a substrate; and
attaching at least a first and second lead electrically connected to the resistor for transmitting an electrical signal.
35. The method according to claim 34 , further comprising the step of depositing the resistor on the substrate.
36. The method according to claim 34 , further comprising the step of forming the resistor by dispersion hardening the oxide selected from the group consisting of: yttrium oxide, cerium oxide, zirconium oxide, and combinations of these within grain boundaries and a main body of the at least one noble metal.
37. The method according to claim 34 , further comprising the step of applying a varying temperature to the resistor to cause a varying resistance in the resistor.
38. The method according to claim 37 , further comprising the step of applying electrical power to the resistor.
39. The method according to claim 38 , further comprising the step of electrically connecting an electrical current source to the resistor.
40. The method according to claim 34 , further comprising the step of generating an electrical signal that comprises a varying voltage that is a function of the varying resistance of the resistor.
41. The method according to claim 40 , further comprising the step of transducing the varying voltage to generate a transducer output.
42. The method according to claim 41 , further comprising the step of correlating the transducer output to a temperature.
43. A sensor which is resistant to degradation at high temperature; said sensor comprising:
a substrate formed with a thin insulating coating from at least one noble metal and an oxide selected from the group consisting of: yttrium oxide, cerium oxide, zirconium oxide, and combinations of these;
a resistor, disposed on said substrate, formed from an oxide selected from the group consisting of: yttrium oxide, cerium oxide, zirconium oxide, and combinations of these, said oxide dispersion hardened within a grain boundary and body of platinum;
at least a first and second lead connected to the resistor for transmitting an electrical signal; and
a transducer.
44. The sensor of claim 43 , wherein a varying temperature causes a varying resistance in the resistor.
45. The sensor of claim 44 , wherein, a power source is applied to the resistor.
46. The sensor of claim 45 , wherein said power source comprises an electrical current source.
47. The sensor of claim 46 , wherein said electrical signal comprises a varying voltage applied to an input of said transducer.
48. The sensor of claim 47 , wherein said transducer generates a transducer output that correlates to an ambient temperature around said resistor.
49. The sensor of claim 43 , wherein said resistor is a resistance temperature device adapted to measure ambient temperatures up to 1700° C.
50. The sensor of claim 43 , wherein said resistor is a resistance temperature detector.
51. The sensor of claim 43 , wherein said resistor is a heat flux sensor.
52. A modular sensor system for generating and sending a signal from a sensor to a transducer comprising:
a sensor for generating a signal having,
a substrate formed with a thin insulating coating from at least one noble metal and an oxide selected from the group consisting of: yttrium oxide, cerium oxide, zirconium oxide, and combinations of these;
a resistor, disposed on said substrate, formed from at least one noble metal and an oxide selected from the group consisting of yttrium oxide, cerium oxide, zirconium oxide, and combinations of these, said resistor further having first and second conductors electrically connected thereto;
a transmit lead module for transmitting the signal to the transducer, said transmit lead module having,
a first transmit lead electrically connected to the first conductor;
a second transmit lead electrically connected to the second conductor, said second transmit lead comprising a different material than said first transmit lead;
an insulating layer within which said first transmit lead and said second transmit lead are located; and
an outer layer within which said insulating layer is located.