| 摘要 |
PROBLEM TO BE SOLVED: To provide a paper sheet fatigue determination device, a paper money processor and a paper sheet fatigue determination method capable of much more accurately determining whether paper money are new or old while avoiding or suppressing the enlargement of the device or the increase of costs.SOLUTION: A sound collection control section makes a microphone perform the sound collecting operation of a sound to be emitted from paper money which passes a predetermined position, and a sampling section samples the output signal of the microphone at a fixed period (#12). An amplitude difference calculation section calculates a difference in data values between each sampling data and the next sampling data, sampling data after the next and sampling data after that one as a first amplitude difference, a second amplitude difference and a third amplitude difference respectively for each of sampling data (#14). A plotting section plots points which use the first, second and third amplitude differences as X, Y and Z-coordinates for each of the sampling data in a three-dimensional coordinate system in which the first, second and third amplitude differences are used as an X-axis, a Y-axis and a Z-axis (#15). A determination section determines the fatigue state of paper money on the basis of the distribution of the plotted points in the three-dimensional coordinate system. |
