Accelerometer having a permanent magnet with non-magnetic end members

摘要

An accelerometer has a housing defining a chamber, and a magnetizable fluid 11 within the chamber. A permanent magnet is magnetically suspended within the chamber by the magnetizable fluid with its poles oriented along a displacement axis so as to be displaceable from a null position along the displacement axis by an applied force. At least parts of the outer surface of the permanent magnet in the vicinity of its poles are provided with non-magnetizable end members. A sensing arrangement is provided for detecting displacement of the permanent magnet along the displacement axis and for supplying an electrical signal indicative of the applied force. Such an accelerometer is relatively immune to calibration drift and has high measurement accuracy.