Motor and electric power steering apparatus using motor
US8333259B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 4, 2011 |
| Grant date | Dec 18, 2012 |
| Priority date | — |
| Expiry date | Aug 10, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K29/08
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A magnetic sensor disposed in an axial direction of a shaft of a motor detects the rotation angle of the rotor by detecting magnetism of the magnet that is disposed on one end of the shaft. A first and second conducting wires extend in parallel with an axis of the shaft, and are equidistantly positioned relative to the axis, on a virtual circle that has a center point on the axis of the shaft. The electric current flowing in the first conducting wire and the electric current flowing in the second conducting wire have the same magnitude and the same flow direction with each other at any time. When the first conducting wire and the second conducting wire are on opposite sides relative to the center point of the virtual circle, the magnetic fields around the conducting wires cancel with each other, thereby enabling accurate detection of the rotation angle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.