Method and system for providing a spherical bearing in a thin film motor
US6066909A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 1998 |
| Grant date | May 23, 2000 |
| Priority date | — |
| Expiry date | Dec 16, 2018 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C2370/12
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electric motor having a pancake construction stator and rotor poles that are formed by photolithography. The stator and rotor can be formed from an amorphous material, thereby reducing grain boundaries and allowing smaller poles to be etched. The number of poles, never less than three, can be from 20 to 5000 times the stator diameter in centimeters. The extremely thin rotor comprises a flexible disk spaced from the stator by an air cushion maintained in accordance with forces as dictated by Bernoulli's principle. This insures that the spacing between the rotor and stator is automatically adjusted to minimize the distance between the rotor and stator poles and thereby to maximize flux linkage between the poles. By operating the motor in a range that avoids saturation of the poles, a variable torque motor is provided since increased current through the motor windings allows the magnetic field intensity and thus the flux linkage to increase. Furthermore, by varying the frequency at which the stator windings are fired, the speed of rotation of the rotor can be adjusted. Since an amorphous material such as METGLAS displays high coercivity, rapid changes in frequency can be achieved a…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.