Patent ID: 6242905
Filing Date: 2001-06-05
Classification: G01D,G01P

Abstract:
A method of identifying a direction of rotation of a wheel, which comprises:disposing Hall probes including a first Hall probe, a second Hall probe and a third Hall probe in succession in a circumferential direction of the wheel, the second Hall probe disposed between the first Hall probe and the third Hall probe, the first through third Hall probes generating output signals phase-shifted relative to one another;deriving a first evaluation signal and a second evaluation signal from the output signals of the Hall probes, an output signal of the third Hall probe being subtracted from an output signal of the first Hall probe to obtain the first evaluation signal, the output signal of the first Hall probe being added to the output signal of the third Hall probe resulting in a summed value and two times an output signal of the second Hall probe being subtracted from the summed value to obtain the second evaluation signal;sampling one of the first evaluation signal and the second evaluation signal at predetermined sample times resulting in a tested evaluation signal being sampled and the other of the first evaluation signal and the second evaluation signal being a sampling evaluation signal defining the predetermined sample times; andderiving a trend of the tested evaluation signal being sampled, the trend having a direction of rotation definitively assigned to it with reference to the tested evaluation signal sampled at a respective sample time.