Speed sensor for use with vehicle road wheel and including connection line breakage detection
US5422568A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 1993 |
| Grant date | Jun 6, 1995 |
| Priority date | — |
| Expiry date | May 13, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P3/487
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A road wheel speed sensor for use with an automotive vehicle supported on road wheels. A pulsating variation in magnetic flux is produced with rotation of one of the road wheels. A signal converter is provided for converting the pulsation magnetic flux variation into a rectangular pulse signal to switching a transistor on and off. The signal converter is connected through power and signal lines to a processor. The transistor has a base electrode for receipt of the rectangular pulse signal, an emitter electrode, and a collector electrode connected to the signal line. A first resistor is connected between the power line and the signal line. A second resistor is connected between the power line and the emitter electrode of the transistor. A third resistor is connected between the signal line and the ground. The processor calculates a speed of rotation of the road wheel in response to a voltage developed across the third resistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.