FR2281554A1 - Bottle size checking method using acoustic resonance - uses acoustic source and detector connected to comparator - Google Patents

Abstract

Each of the bottles (1) is excited by acoustic waves from a source (3) positioned below the path of movement of the bottles (1) and detector (5) is positioned above the neck of the bottle, for receiving the resonance wave emitted by the bottle in response to the acoustic waves. The signal provided by the detector (5) is supplied to a comparator for comparison with a reference signal which is provided by a second detector (6) positioned above the neck of a standard bottle (2) which is excited by acoustic waves from the same source (3) as the test bottle. The comparator (8) may be connected to an oscilloscope display (9) for direct comparison of the two detector signals.