Method and apparatus for the highly accurate determination of the filling level of a product in a container

US6415660B1 · kind B1 · utility

Assignee

• Endress+Hauser Inc. · DE

Inventors

• Michael Sinz · Duvall, US
• Roland Muller · Weiling, DE
• Dietmar Spanke · Steinen, DE
• Robert Lalla · Bad Kötzting, DE

Key dates

• Filing date: Apr 17, 2000
• Grant date: Jul 9, 2002
• Expiry date: Apr 17, 2020

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S13/88
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The invention relates to a method for the highly accurate determination of the filling level (q) of a product (4) in a container (2), measuring signals being transmitted in the direction of the surface (5) of the filled product (4) and reflected at the surface (5) as echo signals and the filling level (q) in the container (2) being determined by evaluation of the amplitude values (A) and phase values (&psgr;) of the reflected echo signals by means of a pulse delay-time method. Furthermore, an apparatus suitable for carrying out the method is proposed.The invention is based on the object of proposing a method and an apparatus which permit highly accurate filling level measurements in containers (2), even if multipath propagation or multimode propagation occurs.The object is achieved by compensating for errors which occur in the determination of the filling level (q) and are caused by interference signals which interfere constructively or destructively with the echo signals reflected regularly at the surface (5) of the filled product (4).