Device for the electric monitoring of the level of a liquid contained in a container
US4425795A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 1981 |
| Grant date | Jan 17, 1984 |
| Priority date | — |
| Expiry date | Jun 12, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F23/24
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A device for the electric monitoring of the level of a liquid contained in a container, comprising at least one temperaturedependent resistance sensor immersed in the liquid the level of which is to be monitored, a constant current source being connectable to the resistance sensor under the control of a program control device controlling a device for detecting and storing the initial voltage drop on the resistance sensor at an initial time and the measurement voltage at a specified time after connection of the constant current source, and a device for evaluating the voltages by subtracting the measurement voltage from the initial voltage and under the circumstances inverting the difference to form a display voltage which corresponds to the level of the liquid. Several of these resistance sensors are arranged at different levels within the container, the sensors being connectable one after the other, controlled by the program control device, to the constant current source and to the device for evaluating the voltage drop on them. A fixed-value storage provides a supply of fixed-value voltages one of which respectively is selectably dependent on the respective resistance sensor activ…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.