Test device for dynamically measuring the degree of dirt accumulation on bank-notes

US4189235A · kind A · utility

Assignee

• GAO Gesellschaft für Automation und organisation mbH · DE

Inventors

• Norbert Guter · Munich, DE
• Josef Gier · Munich, DE
• Herbert Bernardi · Arget, DE
• Erhard Lehle · Mühlheim am Main, DE

Key dates

• Filing date: Nov 29, 1977
• Grant date: Feb 19, 1980
• Expiry date: Nov 29, 1997

Classification

• Technology area (CPC G): Physics
• CPC primary: G07D7/187
• WIPO field: Control
• WIPO sector: Instruments

Abstract

A device for dynamically measuring the degree of dirt accumulation on bank-notes in which certain areas of the bank-note are illuminated and examined by means of a receiving unit. The light from a succession of adjacent elemental areas of a bank-note so illuminated is dependent upon the degree of dirt accumulation and is converted into a corresponding electric signal. The signal is analyzed to determine the number and amount of changes due to dirt accumulated in creases, and the analyzed signal is integrated to determine whether or not the number and nature of areas of accumulated dirt makes the ban-note unsuitable for further circulation.