| 摘要 |
PURPOSE:To prevent a bill from being damaged so as to detect a double feed with no influence to a pattern of the bill by providing an ultrasonic transmitter vertically upward relating to a conveying direction of the bill, ultrasonic signal receiver after the bill passes and a waveform analyzer of an output signal in an opposite side to the ultrasonic transmitter. CONSTITUTION:An ultrasonic transmitter 1 is provided vertically upward relating to a conveying direction C of bills 4, 5 to generate an ultrasonic signal relating to the bills 4, 5. An ultrasonic receiver 2 is provided in an opposite side to the transmitter l relating to the bills 4, 5 to receive the ultrasonic signal transmitted from the transmitter 1 to pass through the bill 4 or 5. Further, a waveform analyzer 6 inputs an output signal 101 of the receiver 2 to analyze a waveform of the output signal 101. When the bills 4, 5 are advanced in a direction of an arrow mark C in a doubled condition in a part B to come between the transmitter 1 and the receiver 2, the output signal 101 of the receiver 2 generates a large output in a part A with only the 4 bill and a small output in the part B with the bills 4, 5 overlapped. Then, the waveform analyzer 6 detects a difference between the outputs and a double feed of the bills. |
