Notched magnet for use in voice coil actuators
US6703727B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 27, 2003 |
| Grant date | Mar 9, 2004 |
| Priority date | — |
| Expiry date | Feb 13, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K1/02
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An improved magnet for use in voice coil actuators is disclosed. The improved magnet includes first and second ends and a top surface, which includes one or more reversed slope notches. Each reversed slope notch may be located in proximity to the ends of the magnet, and may be located such that the magnet is shaped symmetrically about its center. The reversed slope notch is generally characterized in that it includes a notch surface which slopes downward towards the associated end of the magnet. The reversed slope notch or notches minimize the drop-off of force of the voice coil actuator near the ends of the actuator's stroke. In one embodiment, the magnet is part of a linear voice coil actuator that includes a return structure enclosing a magnet and an air gap. In this embodiment, the top surface of the magnet is located adjacent the air gap, and a current-carrying coil travels through the air gap.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.