Electrostatic micromotor
US4997521A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 1989 |
| Grant date | Mar 5, 1991 |
| Priority date | — |
| Expiry date | Apr 25, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02N1/004
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electrostatically driven microactuator is micromachined in a monolithic process. Sacrificial layers are placed between a moving element and stator structural layers. Removal of the sacrificial layers leaves a free standing moving element and micron wide air gaps within a stator. An electric field of about 100 Mv/m and higher is supported across the micron wide gap without breakdown and enables high energy torque densities to be produced between the stator and the moving element. One electrostatic drive scheme involves a series of stator electrodes attached to the stator and a series of electrodes attached to the moving element charged in sequence to attract each other in a direction of movement and to oppose each other in a direction normal to movement. A bearing is aligned with the moving element within the stator during the layering of a sacrificial layer over an edge of the moving element structural layer. The bearing and stator laterally stabilize the moving element. Vertical stability is through aerodynamic shaping of the moving element, electronic circuits, or bushings. Applications of the microactuator include a linearly sliding shutter, an optical modulator, a gyroscope …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.