Accelerometer with integral bidirectional shock protection and controllable viscous damping
US4882933A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 3, 1988 |
| Grant date | Nov 28, 1989 |
| Priority date | — |
| Expiry date | Jun 3, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P2015/0828
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A micromachined accelerometer includes integral bidirectional shock protection and controllable viscous damping. The accelerometer includes a frame in which a seismic mass is disposed and coupled to the frame by one or more cantilever beams. Upper and lower stops are provided around the periphery of the seismic mass and around the interior of the frame to limit the travel distance of the seismic mass. The accelerometer is fabricated, preferably from monocrystalline silicon, by defining an annular recess which extends into a first surface of a silicon substrate. Next, a layer is formed over the surface of the substrate but not in contact with the lower surface of the recessed region. An annular-shaped region of the substrate extending from the bottom surface of the substrate to the layer is then removed to define the seismic mass and frame. Finally, portions of the layer are removed to define the cantilever beams and integral bidirectional stops.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.