| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce temperature drift caused by an ultrasonic oscillator. <P>SOLUTION: A pair of ultrasonic oscillators 2 and 3 is disposed at both ends of a pipe line 1 where a fluid to be measured S flows. Coaxial cables 4 and 5 are connected with the ultrasonic oscillators 2 and 3, respectively, and connected with a transducer 8 via attenuators 6 and 7, which are an element where electrical loss is generated. By inserting the attenuators 6 and 7 that generate losses into the coaxial cables 4 and 5, which are a transmission line, it is possible to make a degree of impedance mismatch small. Therefore, since changes in impedance decreases when viewing the ultrasonic oscillators 2 and 3 from the transducer 8, it is possible to reduce changes in a transmission time of a signal caused by changes in characteristics of the ultrasonic oscillators 2 and 3 due to temperature variation. <P>COPYRIGHT: (C)2012,JPO&INPIT |
