Ultrasonic flow meter having deterioration suppression in flow rate accuracy

摘要

An ultrasonic flow meter is equipped with a housing through which a liquid flows, and a pair of detection units disposed on opposite ends of the housing and including acoustic wave transmitting and receiving units capable of transmitting and receiving acoustic wave signals. Paired connecting plugs are connected respectively to both ends of the housing. In addition, a supply passage of one of the connecting plugs, a conduit of the housing, and a discharge passage of another of the connecting plugs are disposed on a straight line. A liquid supplied to the supply passage flows through a passage of the conduit and to the discharge passage. Consequently, a flow rate of the liquid is measured based on the propagation time of the acoustic wave signals, which are transmitted and received by the acoustic wave transmitting and receiving units.