Case hardened thermometer
US4158966A · kind A · utility
Inventor
Key dates
| Filing date | Jul 27, 1977 |
| Grant date | Jun 26, 1979 |
| Priority date | — |
| Expiry date | Jul 27, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01K13/25
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved thermometer which is case hardened and includes a total enclosure composed of a pair of first and second layer members covering the stem portion and the bulb portion respectively of the thermometer. A substantially transparent plastic material layer member covers the stem portion of the improved thermometer and has an index of refraction which is sufficiently high to allow a user to visually interpret the location of an internally contained heat expandable substance in relation to indicia formed on the stem portion. Additionally, the first layer member is irradiated from a source of soft Beta rays for hardening the outer surface layer of the first layer member. The bulb section of the improved thermometer is enclosed by a second thermally conductive layer member. Both the first and second layer members are joined to form a total enclosure for the thermometer throughout the extended length of both the bulb and stem portions. Additionally, an increased amount of substantially transparent plastic material is added to the terminal end of the stem portion of the improved thermometer in order to provide a cushioning effect under dynamic load when the thermometer inadvertently…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.