Biaxial strain gage systems
US4683755A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 15, 1985 |
| Grant date | Aug 4, 1987 |
| Priority date | — |
| Expiry date | Nov 15, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49103
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Biaxial strain gage and similar systems include or provide a substrate of semiconductor material having cubic unit cells and an absolute value of piezoresistive coefficient in a first direction different from an absolute value of piezoresistive coefficient in a second direction transverse to said first direction. A first strain gage has a dominant dimension oriented in the above mentioned first direction and is diffused into the substrate. A second strain gage has a dominant dimension in the above mentioned second direction and is diffused into the substrate. A pressure responsive diaphragm having a central area displaying essentially symmetrical biaxial strains is provided, and the substrate is attached in said central area to the diaphragm to expose the gages to the biaxial strains. Additionally, third and fourth strain gages may also be provided, but in either case, all strain gages are located within an area of the substrate corresponding to the central area of the diaphragm displaying essentially symmetrical biaxial strains.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.