Abstract: A capacitive tamper detection system for safes, ATMs and cash storage devices deters theft and vandalism without damaging the safe or the currency contained within the safe. One or more sensor plates are mounted to the interior walls and/or door of the safe. The sensor plates are separated from the walls and/or door of the safe by a dielectric to form, along with the walls or door of the safe, one or more capacitors. The capacitors formed by the sensor plates and the walls and/or door of the safe are part of an RC circuit having a time constant that depends on the capacitance. The time constant of the RC circuit causes an astable multivibrator to oscillate at a particular frequency, outputting a frequency signal. Changes in the capacitance caused by damage to the walls and/or door of the safe changes the time constant of the RC circuit, which in turn changes the frequency signal.

Abstract: A filter disk filters coins deposited into coin machines for counting, sorting, separating or processing coins to prevent the introduction or entry of foreign objects and debris into the coin machine, thus protecting and ensuring the proper functioning of the machine.

Abstract: A filter disk filters coins deposited into coin machines for counting, sorting, separating or processing coins to prevent the introduction or entry of foreign objects and debris into the coin machine, thus protecting and ensuring the proper functioning of the machine.