Electromagnetic actuator
US7358629B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 2004 |
| Grant date | Apr 15, 2008 |
| Priority date | — |
| Expiry date | Aug 27, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K1/141
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The rotational torque of an electromagnetic actuator having a stator and rotor, such as a stepping motor, is increased.The electromagnetic actuator includes a rotor (30) having multiple magnetic poles (Nr1, Nr2, Nr3, Nr4, Nr5, Sr1, Sr2, Sr3, Sr4, Sr5) on a circumferential surface (31) and a plurality of stators (10, 20) in an electromagnet form. The stator (10, 20) has a pair of magnetic poles (13, 14, 23, 24) facing the circumferential surface (31) of the rotor (30), and an auxiliary yoke (40, 50) made of a soft magnetic material member extending in a circumferential direction (A) over an angular range (γ1, γ2) larger than a spread angle (α) of the magnetic poles (Nr, Sr) of the rotor (30) in the circumferential direction (A) is provided between the pair of magnetic poles (13, 14, 23, 24).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.