| 摘要 |
<p>PURPOSE:To measure the cambering amount of a steel plate running on a roller table at a high speed without being influenced by the jump or meander of the steel plate, the temperature of the steel plate, dust in the vicinity of the steel plate, etc., by using the measuring result by an ultrasonic position measuring means. CONSTITUTION:High frequency pulses added to an oscillating vibrator 7a are radiated into the space as ultrasonic waves, reflected at an edge face of a steel plate 1 and returned to a detecting element 7b. The delay time t2 of the reflecting waves at this time is represented by t2=X/V wherein X is the distance from an ultrasonic probe 7 to the edge face of the steel plate 1. Since the V indicating the sound velocity in the air is changed by the temperature, the ultrasonic waves are partly reflected at a calibrating point 7c and a part of the reflected waves is reflected at the calibrating point 7c, thereby to obtain the sound velocity V from the delay time t1 of the reflected waves and the known distance 10. The distance, namely, the position X of the edge of the steel plate 1 is obtained irrespective of the temperature of the air according to an equation X=(t2/t1).10.</p> |
