Infrared analyzer, especially for foodstuffs such as flour

US4479055A · kind A · utility

Inventor

• Peter Perten · Marl, DE

Key dates

• Filing date: Mar 11, 1982
• Grant date: Oct 23, 1984
• Expiry date: Mar 11, 2002

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2021/8592
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An analyzer for relative (percent etc.) measurement of amounts of certain substances, especially protein, water and/or oil in powdered, pulp-like or other non-rigid foodstuffs, is made to alternatingly irradiate a sample and a reference with collimated monochromatic IR-light. Both the sample and the reference are irradiated several times with light of various wavelengths in sequence. Photocells in an open spherical chamber, a so-called Ulbricht ball, receive from the sample and from the reference reflected diffuse light and convert it to electrical signals. In the beam path there is a window which allows said wavelengths to pass and which is in direct contact with the sample, which is thus not provided with a casing or own covering glass or the like. The sample is placed in a sample holder, which is formed by the window, possibly with a wall portion around said window, and a wall directly opposite to the window. The sample holder is completely closed when used but has an opening at one edge and a fixed or spring-biased bottom on the opposite edge. Between the wall and the window there is thus a space for filling with the sample through the opening in a direction transverse to the a…