Method and apparatus for performing the setting-up of the fault-signal evaluating circuitry of an apparatus which detects unacceptable faults in glass bottles, and the like

US4140901A · kind A · utility

Assignee

• Hermann Heye

Inventors

• Knut Fischer · Bad Eilsen, DE
• Gerhard Geisel · Bückeburg, DE

Key dates

• Filing date: Apr 27, 1977
• Grant date: Feb 20, 1979
• Expiry date: Apr 27, 1997

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N21/9072
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The apparatus includes a photoelectric sensor associated with a predetermined zone of a hollow glass article to be examined for faults. During one testing operation, the photoelectric sensor successively detects all faults in that zone and generates for each a fault signal whose value is dependent upon the characteristics of the fault. The fault signals are applied to a threshold circuit which generates an output signal only when the fault-signal value exceeds a threshold-signal level. The setting-up procedure involves performing at least one preliminary testing operation upon a preselected sample or standard article having acceptable faults. Each threshold-circuit output signal automatically results in a circuit adjustment which reduces by a predetermined amount the extent to which the respective fault-signal value exceeds the threshold-signal level. The preliminary testing operation is performed repeatedly, until the largest-value fault signal generated during one testing operation has a value slightly below the threshold-signal level, whereupon the testing apparatus has been properly set-up automatically. Thereafter, testing operations are performed upon articles whose eventual …