Method of and apparatus for measuring the moisture content of fibrous materials

US5086279A · kind A · utility

Assignee

• Korber AG · DE

Inventors

• Waldemar Wochnowski · Hamburg, DE
• Heiko Niehues · Hamburg, DE

Key dates

• Filing date: Feb 23, 1990
• Grant date: Feb 4, 1992
• Expiry date: Feb 23, 2010

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2021/845
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A hygroscopic commodity, such as a continuous stream of shredded tobacco, is transported past one or more sources of electrical energy and past one or more monitoring devices. One of the sources can expose the stream to the electric field of a capacitor in a high frequency oscillator circuit, and the other source can expose the stream to infrared waves or microwaves. The moisture in the stream influences the phase and/or the damping of oscillations of the electrical energy, and the monitoring device of devices ascertain the changes of such characteristics of the electrical energy and transmit corresponding signals to a processing circuit which processes the signals into moisture signals. The processing circuit can generate first quotient signals which are indicative of phase shift and damping of oscillations of electrical energy which has penetrated the stream, and second quotient signals denoting the phase shift and damping of waves which are reflected by the stream, and such first and second quotient signals are or can be averaged for processing into moisture signals. The moisture signals are not dependent upon the chemical and/or biological properties and/or upon the composition…