Engine operation detection
US5705999A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 5, 1995 |
| Grant date | Jan 6, 1998 |
| Priority date | — |
| Expiry date | Jun 5, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08G1/042
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A method and apparatus is provided for determining if a vehicle with an operating engine is at a particular location, the apparatus comprising: an antenna comprising a continuous wire formed into at least one loop; and a means to determine when the antenna is exposed to an oscillating electromagnetic field having a frequency between about 700 and about 2100 Hz of a strength characteristic of a vehicle's alternator operating in the vicinity of the antenna. In a preferred embodiment of the present invention, the sensor of the present invention further comprises a means to generate a signal when the antenna is exposed to the oscillating electromagnetic field having a frequency between about 700 and about 2100 Hz of a strength characteristic of a vehicle's alternator operating in the vicinity of the antenna, and the signal is used as an input into a logic system that requires that the signal not be generated in order for a refuelling system to refuel a vehicle in the vicinity of the antenna. The antenna is preferably a figure eight loop antenna placed in pavement below the location at which the vehicle is expected to be. The sensor of the present invention is particularly applicable as…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.