| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an ultrasonic distance measuring instrument capable of quickly measuring a distance to a measuring target and prevents measurement accuracy by multiple reflection of an ultrasonic wave from deteriorating, and a transport machine including the same. <P>SOLUTION: A transmission element 50 transmits an ultrasonic wave in each measuring period. A reception element 60 receives the ultrasonic wave reflected at the measuring target, and outputs a reception signal corresponding to the intensity of the received ultrasonic wave. A reflection time measuring part 90 calculates a time corresponding to a distance to the measuring target on the basis of a position on a time base of a first reflection component of the reception signal. A peak holding part 110 holds the maximum value of the first reflection component. A variable power supply 140 adjusts the intensity of an ultrasonic wave transmitted by the transmission element 50 in the next measuring period on the basis of the held maximum value such that the first reflection component appears in the next measuring period and that the appearance of a second reflection component is suppressed. <P>COPYRIGHT: (C)2013,JPO&INPIT |
