Apparatus and method to non-intrusively measure the level of liquid in a sealed container
US6536276B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 2001 |
| Grant date | Mar 25, 2003 |
| Priority date | — |
| Expiry date | Mar 4, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F23/22
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A liquid level sensor used for determining liquid levels in a sealed container includes a heat source bonded to the container, a first temperature sensor mounted on the container adjacent the heat source, and a second temperature sensor mounted on the container spaced from the heat source. The temperatures at the first and second temperature sensors are sensed while the heat source is operating, and the differential in the temperatures is measured and used to control power to the heater. Changes in the differential in temperature between the first and second temperature sensors indicates when the heat conductivity between the first and second temperature sensors changes, due to presence or absence of a liquid in the container at the level of the temperature sensors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.