Linear magnetic sensing device

摘要

A magnet device having a predetermined field profile has an elongated permanent magnet, having a longitudinal axis and a peripheral surface, magnetized diametrically with the direction of magnetization extending transversely to the longitudinal axis and rotating about at least a portion of the length of the longitudinal axis of the magnet. The rate of rotation is selected to provide a predetermined magnetic field profile as presented to a Hall effect device positioned a fixed distance from the peripheral surface of the magnet when relative movement between the Hall effect device and the permanent magnet occurs. The magnet is formed of a composite material which includes a magnetically isotropic permanent magnet powder adhered together by an adhesive non-magnetic binder.