Patent Number: 7,710,110

Title: Rotary sensor with rotary sensing element and rotatable hollow magnet

Abstract: A robust solution for eccentricity issues in 360 degree rotary sensor application utilizing a hollow cylindrical magnet. A hollow cylindrical magnet design can be implemented to drive a parallel field magnetic sensor based on Hall/AMR technologies. Eccentricity variations of +/-0.46 mm on X and Y axes can be reduced by at least 20%, in turn improving the repeatability, linearity error and a correlation error associated with the sensor. For tilts of +/-3 degrees, the error can be reduced to at least 50% compared to a solid magnet, thereby increasing the repeatability and accuracy of the rotary sensor. The disclosed design improves linearity, is robust in vibration and improves reliability in lifecycle as the sensor configuration is less affected by wear and tear due to mechanical vibrations.

Inventors: Patil; Swapnil (Thane, IN), Hasan; Nurul I. (Bodinayakanur, IN), Krishna; Suresh (Thuraiyur, IN), M; Azhagar Raj (Vilathikulam, IN), Salunke; Vivek (Bangalore, IN)

Assignee: Honeywell International Inc.

International Classification: G01B 7/30 (20060101)

Expiration Date: 5/04/12018