Patent · US Expired

Rotational angle detecting device

US7034525B2 · kind B2 · utility

3Cited by
4References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 7, 2004
Grant dateApr 25, 2006
Priority date
Expiry dateJun 7, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01D5/142
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

In a rotational angle detecting device, an auxiliary magnet is disposed so as to surround a Hall element around the Z-axis, so that variation of offset magnetic flux is suppressed even when the position of the Hall element is displaced in the X-axis direction with respect to the auxiliary magnet. In addition, even when the fabrication position of the Hall element is displaced in the Y-axis direction of the auxiliary magnet, the variation of the offset magnetic flux is suppressed. By adjusting the dimension (the length in cylinder direction) in the Z-axis direction of the auxiliary magnet, the variation of the offset magnetic flux is suppressed even when the Hall element is displaced from the center of the auxiliary magnet in the Z-axis direction. That is, even when the position of the Hall element is displaced from the center of the auxiliary magnet in the three-dimensional direction, the displacement of the offset magnetic flux can be prevented, and thus reduction of the detection precision can be prevented.

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