Angular position pick up for measuring high linear flux density

Abstract

An angular position sensor is provided which is designed to an angular position of a rotary shaft. The angular position sensor has a magnet affixed to the rotary shaft. The magnet has an N-pole and an S-pole and is so geometrically shaped as to produce magnetic flux which is substantially uniform in amount within a range extending around each of centers of the N-pole and the S-pole. This improves the linearity of a change in sensor output upon rotation of the rotary shaft.

Description

technical field [0001] This invention relates generally to angular position sensors for measuring the angular position of rotating parts, and more particularly to an improved structure for such angular position sensors designed to sense a more linear magnetic flux density. Background technique [0002] A typical angular position sensor for measuring the angular position of a rotating shaft consists of a ring magnet, a yoke and a plurality of magnetic sensors. The ring magnet has N poles and S poles arranged in its circumferential direction. the periphery of the magnet. The yoke has radial grooves formed therein, the radial grooves forming an air gap. Magnetic sensors are arranged in the air gaps and are used to measure the magnetic flux density in these air gaps. For example, US Patent No. 5,528,139 (corresponding to Japanese Patent No. 2842482) issued to Oudet et al. on June 18, 1996 discloses this type of angular position sensor. [0003] The N pole and the S pole of th...

AI Technical Summary

Problems solved by technology

Determining the absolute angular position of the axis of rotation requires extensive computation of trigonometric functions and / or the use of mappings, which poses the problem of an undesirably large computational burden on the system

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