Multi-Pole Magnetic Encoders for Active Speed-Measurement Systems Freudenberg-NOK General Partnership

Format:

Book

Conference/Event

Author/Creator:

Nachtigal, Daniel, author.

Conference Name:

Annual Brake Colloquium And Engineering Display (1999-10-10 : Miami, Florida, United States)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 1999

Summary:

Automotive wheel speed sensors have generally been based on principles of magnetic field sensing. "Active" sensors, as Hall and Magneto-Resistive, overcome some drawbacks of the previous systems. However, recent conceptual advancements, focusing on the tone-wheel, have proved significant for system performance. The tone-wheel is replaced in fully active systems by a precise ring of steel, bonded to magnetized rubber, where multiple poles are produced in the circumference. The ring serves as an encoder for magnetic sensors, eliminating the need for a large, strong permanent magnet on the sensor - thus significantly reducing size. Active sensor and encoder allow detectable speeds down to zero, improved accuracy, and significantly larger air-gaps and allowable tolerances. These properties, in turn, provide major advantages in manufacture and assembly costs. Usage of elastomeric compounds provides excellent mechanical, dynamic and environmental behavior. Furthermore, many speed-sensing systems are integrated at shaft-ends or in the vicinity of bearings, where seals are required. Elastomeric encoder technology allows combination of multiple functions, as sealing, into a single component - thereby reducing the number of parts

Notes:

Vendor supplied data

Publisher Number:

1999-01-3402

Access Restriction:

Restricted for use by site license