| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent a permanent magnet from being demagnetized, make the flux hardly saturating in a core and allow an inverter controller to be made small in size by generating a bias fluxed by a permanent magnet and flux by a coil so that both fluxes are opposed in the core and providing a flux detector in a magnetic gap. SOLUTION: A coil 3 is wound round a center leg 1c so that the fluxϕe of this coil directs from this leg 1c to a magnetic gap 5, resulting in that this fluxϕe of the coil 3 is opposed to a bias fluxϕm of a permanent magnet 4 to form a flux generating means with the magnet 4 and coil 3 which generate opposed fluxes running in a core structure 10 such that the flux of the magnet 4 in the gap 5 runs in the magnet 4 to bias the gap 5. A small flux detector FD such as Hall element or search coil is disposed in the magnetic gap 5 to detect the fluxϕe of the coil 3.</p> |
