Actuator with minimized auxiliary magnet, and throttle device provided with such an actuator
US5870010A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 23, 1997 |
| Grant date | Feb 9, 1999 |
| Priority date | — |
| Expiry date | Jun 23, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D11/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electrical actuator for a throttle device has a stator and a rotor, the rotor being coupled to the throttle device and comprising a permanent main magnet. The stator includes in axially extending slots therein auxiliary permanent magnets which interact with the rotor magnet to exert a magnetostatic torque (T.sub.MS) on the rotor which tends to rotate it to a pre-set rest position. The stator also has an energizing coil which when actuated results in an electromagnetic torque (T.sub.EM) on the rotor which is opposed to the magnetostatic torque and causes the rotor to pivot through a limited angle of rotation. The thickness and width of the auxiliary permanent magnets are selected so that the cross-sectional area thereof provides a maximum value of the magnetostatic torque (T.sub.MS) per unit volume thereof, thus minimizing the necessary volume and weight of the auxiliary permanent magnets.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.