Electrical temperature measuring resistor structure, particularly for resistance thermometers
US4050052A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 14, 1976 |
| Grant date | Sep 20, 1977 |
| Priority date | — |
| Expiry date | Jun 14, 1996 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01C17/12
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A substrate carrier of electrically non-conductive material has a strip of resistance platinum applied thereto; in order to avoid the use of an intermediate temperature coefficient of expansion matching layer, the substrate carrier, for example of aluminum oxide, beryllium oxide, or a magnesium silicate, has less than thirty parts per million (ppm) Fe, less than 15 ppm Cr, less than 45 ppm Pb and less than 70 ppm Si in a form capable of reacting with platinum, the sum of the impurities by these metals, if all, or more than one are present, not exceeding 20 ppm; the average thermal coefficient of expansion of the substrate does not deviate from the mean thermal coefficient of expansion of the thermometer grade platinum by more than .+-. 30%; the platinum layer has a thickness of from 0.1 to 10 .mu.m, and is applied at a temperature in the range of between about 1000.degree. C to 1400.degree. C during 60 minutes in an atmosphere containing oxygen, for example free air.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.