Patent ID: 8689638

Claim:
An ultrasonic flow sensor consists of: a flow cell body with an inlet on one side and an outlet on the other side through which the liquid or gaseous media flows, an inner flow conduit with rough surface which not only decreases the flow transition point from turbulence regime to laminar regime but also suppresses the parasitic multi-mode ultrasonic waves, one pair of electro-ultrasonic transducers for transmitting and receiving ultrasound signals, one pair of ultrasonic wave reflecting mirrors with flat or convex top surface for guiding the ultrasonic wave from one transducer to the other, and one pair of reflecting mirror support fixtures which align the reflecting mirrors to the center line of the inner flow conduit and also keeps the distance between the reflecting mirrors and the entrance/exit of the inner flow conduit in a range that the disturbance to the flow inside the inner flow conduit caused by the reflecting mirrors is minimized while the ultrasonic signal strength is maintained.