System for indicating and signaling the presence of snow and ice
US5418522A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1991 |
| Grant date | May 23, 1995 |
| Priority date | — |
| Expiry date | Oct 15, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B19/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A moisture sensor with two heatable concentric moisture electrodes and a temperature sensor detecting the electrode temperature is set into the roadway surface to be monitored. The moisture electrodes are heated by a heating current circuit. The heating current circuit is connected to a computer which has a store for storing device-specific parameters, desired values and a processing program. During each measuring cycle the computer processes the temperatures of the moisture electrodes measured by the temperature sensor and a signal which is representative of the surface moisture. A control signal is produced therefrom which heats the moisture electrodes. An alarm or switching signal is produced when the moisture electrodes have reached a temperature characteristic of the formation of ice and a conductivity indicative of moisture is present between the moisture electrodes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.