| 摘要 |
<p>The present invention relates to a method for detecting two papers using a noise signal value of an ultrasonic sensor and, more specifically, to the method for detecting two papers using the noise signal value of the ultrasonic sensor, which can detect two papers of notes effectively under various environmental conditions without regard to variation of a ultrasonic sensor receiving part detection signal value according to the surrounding temperature, by setting a reference value by measuring the noise signal value detected in the ultrasonic sensor receiving part, if insertion of notes is detected, and measuring an ultrasonic signal value going through the notes through the receiving part by irradiating the ultrasonic wave through a generation part as passing the notes thereafter, and judging occurrence of two papers of the notes in case the measured signal value is equal to or less than a previously established reference value, in detecting two papers of notes inserted into an automatic teller machine using the ultrasonic sensor. For this, in the method for detecting two papers of the notes using the ultrasonic sensor comprising the ultrasonic generation part and the ultrasonic receiving part, the present invention provides the method for detecting two papers using the noise signal value of the ultrasonic sensor, which sets the reference value of two-paper judgment by measuring a voltage value of the noise signal detected in the ultrasonic receiving part under operation stop state of the ultrasonic generation part, and receives the ultrasonic signal passing through the notes by operating the ultrasonic generation part as passing the notes, and judges occurrence of two papers in the notes passing a return path in case the measured voltage value is equal to or less than the established reference value by measuring the voltage value of the received signal.</p> |
