Single-phase semiconductor electric motor and fan using the same
US4755728A · kind A · utility
Inventor
Key dates
| Filing date | Sep 15, 1987 |
| Grant date | Jul 5, 1988 |
| Priority date | — |
| Expiry date | Sep 15, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/085
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A single-semiconductor motor fan comprises a cylinder; a fixed armature with the central portion fitted over the lower end of the outer periphery of the cylinder and having a plurality of salient poles; a plurality of single-phase armature coils mounted on the armature; bearings fixed on the inner periphery of both ends of the cylinder; a rotary shaft rotatably supported by the bearings; a cup-shaped rotor fixed on the upper end of the rotary shaft; an annular magnet fixed on the inner surface of the rotor and magnetized into N and S poles having the same pitch as those of the salient poles, the N and S magnetic pole surfaces facing the salient pole surfaces with a space therebetween; a radial fan composed of a plastic cylinder fitted over a protruding portion of the rotor and a plurality of plastic plates extending radially outwardly of the cylinder, the height of the radial fan not exceeding the height of the protruding portion of the rotor; a position detecting element for detecting the position of the magnet of the rotor and producing a single-phase position detecting signal; an energization controlling circuit for energizing the armature coil and producing a unidirectional tor…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.