Vehicle road speed signal source
US4083423A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 1975 |
| Grant date | Apr 11, 1978 |
| Priority date | — |
| Expiry date | Jul 2, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P3/487
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A vehicle road speed signal source including a speed sensor and a frequency to voltage converter for generating a pulsed output signal having an average magnitude proportional to the road speed of an associated vehicle. The speed sensor has a high energy product magnet attached to the drive shaft of the vehicle which induces current pulses in approximately spaced pick-up coil. The pick-up coil is connected to a preamplifier having a low input impedance to reduce the effect of spurious signals such as ignition noise. The preamplifier output signal may be shaped into a square wave pulse train or may be applied directly to the frequency to voltage converter which generates a pulsed output signal having a duty cycle and therefore an average magnitude proportional to the vehicle road speed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.