Patent · US Expired

Linear motor

US7425783B2 · kind B2 · utility

5Cited by
1References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 8, 2003
Grant dateSep 16, 2008
Priority date
Expiry dateSep 15, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02K29/08
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A stator portion of a linear motor includes a U-phase coil portion (10U), a V-phase coil portion (10V), and a W-phase coil portion (10W) through which currents with phases different by 120 degrees from one another flow. Each coil portion has pairs of a first coil wound clockwise and a second coil wound counterclockwise. The pairs of coils adjoin to each other in the moving direction and are connected in series and arrayed in the moving direction. When the extension length from the first coil to the second coil is 360 degrees, the V-phase coil portion overlaps with and is shifted from the U-phase coil portion by 120 degrees, and the W-phase coil portion overlaps with and is shifted from the V-phase coil portion by 120 degrees with respect to the moving direction. A magnet portion (30) is movably combined with the U-phase, V-phase, and W-phase coil portions. The length of the magnet portion in the moving direction is less than a half of the wavelength of the magnetic flux generated with the coils. On a movable portion, a Hall element (40) is mounted at the position away from the center of the magnet portion by an integral multiple of a half of the wavelength of the magnetic flux gene…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.