Patent Number: 6,310,474

Title: Method and apparatus for detecting the direction of crankshaft rotation during a single tooth/slot transition

Abstract: A direction of rotation detection apparatus and method using the outputs of a single differential sequential sensor employing two matched magnetostatic elements, ie., either Hall elements or magnetoresistors (MRs), to extract direction of rotation information from the passage of a single tooth edge of a target wheel. The two matched sensing elements are spaced in close proximity to each other, preferably on the order preferably of about 1 mm to about 2 mm apart, in the circumferential direction of the target wheel and generate two identical angularly offset signals from the passage of a single tooth edge of a target wheel which are input to a signal conditioning circuit. Within the signal conditioning circuit, the two sensor signals are differentially amplified to produce a differential signal whereby the polarity of the differential signal enables one of two comparators with respective reference voltages. The output of the enabled comparator is processed and converted into a digital output signal whose voltage level indicates the direction of rotation of the target wheel.

Inventors: Schroeder; Thaddeus (Rochester Hills, MI)

Assignee: Delphi Technologies, Inc.

International Classification: G01D 5/12 (20060101); G01D 5/16 (20060101); G01B 007/14 ()

Expiration Date: 10/30/2018