Vibration sensor including a reduced capacity lower portion for maintaining airtightness and enhancing reliability
US5218870A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 24, 1991 |
| Grant date | Jun 15, 1993 |
| Priority date | — |
| Expiry date | Apr 24, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L23/222
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A vibration sensor is provided in which the depth of a caulked portion of the sensor's case is increased so as to increase the capacity of a recess defined between this caulked portion and the cover. The volume of a potting agent filling the recess can thereby be increased to improve the airtightness of the caulked portion and the reliability of the vibration detector. A vibration plate having cutouts circumferentially spaced along an outer, peripheral portion may be used in the vibration detector if the volume of the space formed on a lower side of the vibration plate is limited to about a few to ten percent of that of the space formed on the opposite, terminal side. The expansion of air in the spaces caused by a thermal shock is therefore substantially equal to the expansion of air contained in the space on the terminal side alone, so that vibration sensor can maintain sufficient airtightness and can be improved in reliability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.