Variable reluctance actuators having improved constant force control and position-sensing features
US4656400A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 1985 |
| Grant date | Apr 7, 1987 |
| Priority date | — |
| Expiry date | Jul 8, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F7/18
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A variable reluctance actuator, of either the linear or rotary type, having a moving element operated by a solenoid, is controlled by a Hall effect sensor signal representative of flux density in the magnetic circuit of the actuator. The actuator may be operated in either a constant-force control mode, or a position-sensing or control mode. Substantially constant force, independent of position of the actuator's movable element, is obtained by varying, rather than stabilizing, the sensed magnetic field during movement. Position sensing, independent of actuator force, is obtained by variably controlling the magnitude of the excitation current of the Hall effect sensor in response to the magnitude of the coil current and Hall sensor output.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.