| 摘要 |
PURPOSE:To improve the accuracy of detecting improper notes, in a device for measuring a distance by receiving the reflected of mechanical vibration transmitted to a traveling medium such as a note by an electrical acoustic element, by emitting an acoustic pulse and accumulating a period until the pulse has returned after it reflects from the medium. CONSTITUTION:In an automatic cash dispenser, a medium 1 which is a note is positioned at a distance L1 from an electrical acoustic element 2 such as a piezoelectric element, and a medium 1' is bent in a L-shape and positioned at a distance L2 from the acoustic element 2. In the event of improper detection of the medium 1, a distance between the acoustic element 2 and the medium 1' is measured and a distance between the acoustic element 2 and the medium 1 is measured in order, when the medium 1 travels in an arrow direction. Respective measurements are inputted to a driving measurement part 3. A period until an acoustic pulse emitted from the acoustic element 2 has returned after it reflects at the medium 1, 1' is accumulated in a time series, so that it is possible to detect irregularity of the medium 1, or an improper note with wrinkles or folds. |
