Method and device for determining a liquid level with the aid of ultrasonic pulses

US6202484A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Siegfried Willner · Lichtenfels, DE
• Michael Eisentraudt · Kronach, DE

Key dates

• Filing date: Jul 3, 1998
• Grant date: Mar 20, 2001
• Expiry date: Jul 3, 2018

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S15/88
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for determining a liquid level with the aid of ultrasonic pulses improves the measuring accuracy of the liquid level in a container with an echo time measurement of ultrasonic pulses and a mean sound velocity. The mean sound velocity is extrapolated from at least two reference sound velocities in the liquid. In this way it is possible to achieve a measuring accuracy of less than a millimeter, independently of the liquid level. A device for carrying out the method has a main measuring path, at least one device for transmitting and receiving ultrasonic pulses, at least two reference paths for determining sound velocities, and a computer unit. The computer unit extrapolates from the sound velocities to the mean sound velocity.