Patent ID: 8201453
Filing Date: 2012-06-19
Classification: G01N,G07D

Abstract:
1. A medium fatigue detection apparatus for detecting fatigue of a sheet medium by using fatigue-detecting ultrasonic waves, the medium fatigue detection apparatus comprising: ultrasonic sending means for oscillating fatigue-detecting ultrasonic waves as burst waves; ultrasonic receiving means for sensing the burst waves; sensed intensity detecting means for detecting intensity of the burst waves sensed by the ultrasonic receiving means; and fatigue detecting means for detecting fatigue of the sheet medium by measuring variation in the detected burst wave intensities and detecting fatigue based on a magnitude of the measured variation, wherein the ultrasonic sending means and the ultrasonic receiving means are provided to oppose each other such that fatigue-detecting ultrasonic waves sent from the ultrasonic sending device are incident at a predetermined angle on a principal surface of the sheet medium passing between the ultrasonic sending device and the ultrasonic receiving device.