Abstract: A capacitance sensor measures a coin to determine geometrical parameters thereof and to allow assessment of different geometrical parameters of a coin which influence the measured capacitance. In a preferred arrangement, a mechanical arrangement alters the capacitance between two electrodes as a function of the diameter of the coin. This assessment is used in combination with a further measured capacitance which is a function of coin diameter, coin thickness and surface relief of the coin. The initial evaluation of diameter is useful in determining the separate influences of coin thickness and surface relief. The invention is also directed to the method of coin evaluation.

Abstract: A capacitor sensor for assessing dielectric properties of currency paper uses a transmitting dielectrode on a first side of an evaluation channel and a receiving electrode on the same first side of the evaluation channel. A passive electrode is located on the opposite side of the evaluation channel and overlays with the transmitting and receiving electrodes. An electronic processing arrangement is connected to the transmitting and receiving electrodes and evaluates the signals for changes in the capacitance coupling of the electrode. This coupling is directly related to the properties of the paper passing between the passive electrode on one side and then transmitting and receiving electrodes on the other side.