| 摘要 |
A coin processing machine with a coin discriminator operated by a method is provided. The coin discriminator measures how a coin having an iron core covered by a layer of copper, brass, or bronze affects a coil when the coin is subjected to magnetic fields generated by the coil, external to the coin. Eddy currents induced in the coin are detected external of the coin. The discriminator induces a magnetic field in the coil by driving the coil with time varying drive signals having high frequencies. The coin discriminator receives the coin at precise positions in the magnetic field and detects the eddy currents induced in the coin by measuring the eddy currents through the coil. Then, the coin discriminator compares the measured eddy currents with predetermined values for different types of coils, and determines the structure, materials and type of the coin. |
