Method for determining the current filling level of a liquid in a container

• Main Authors: RUETHER HORST, HUEMER HERFRIED
• Format: Patent
• Language: English
• Published: 23.08.2005
• Edition: 7
• Subjects: BLASTING; HEATING; LIGHTING; MEASURING; MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUIDLEVEL; MECHANICAL ENGINEERING; METERING BY VOLUME; PHYSICS; POSITIVE DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS; TESTING; WEAPONS

The invention relates to a method for determining the current filling level of a liquid, preferably a calibrating, quality control, or cleaning fluid, or waste water, in a container, for example of an analyzer, where an immersion pipe is dipped into the liquid in the container to be filled or drained. The immersion pipe is connected to a pumping device via a tube system. The pressure p in the tube system is measured and increased, starting from the ambient pressure p0, until a first discontinuous pressure change occurs at pressure p1 due to the liquid column in the immersion pipe being forced out of the pipe, and/or the pressure p in the tube system is decreased until the liquid column in the immersion pipe reaches a change in cross-section of the immersion pipe, which change is situated above the maximum filling level of the liquid, such that a second discontinuous pressure change occurs at pressure p2 due to the liquid column reaching the change in cross-section. The pressure difference between ambient pressure p0 and the pressure p1 or p2 at one of the two pressure discontinuities or the time t1 or t2 until one of the two pressure discontinuities is reached, is recorded and used to determine the current filling level of the container.