Abstract: A monitoring device of liquid pipeline includes a fixture detachably fixed to an outer surface of a pipeline, a first ultrasonic probe disposed in the fixture, a processing module having stored a minimum signal threshold, and a display unit connecting to the processing module. The processing module controls the first ultrasonic probe transmitting a first sensing signal and receiving a first reflection signal corresponding to the first sensing signal along a radial direction of the pipeline, and analyzes signal of first period and second period signal from the first reflection signal. If the processing module determines that the signal of first period signal is greater than and the signal of second period signal less than the minimum signal threshold, the processing module generates a warning signal that represents abnormality of the first ultrasonic probe or liquid in the pipeline. The display unit displays the warning signal.

Abstract: A flow meter includes a rotating structure, a sensing element and a processing circuit. The rotating structure has a shaft, a rotating element, and a magnetic element. The rotating element can be driven by a fluid in a pipeline to rotate around the shaft. The magnetic element is arranged on the rotating element with two magnetic poles parallel to a tangent line of rotating circle of the rotating element. The sensing element is separated from the rotating structure by a distance, and includes a first sensing unit and a second sensing unit, respectively sensing a magnetic field of the magnetic element in different directions to generate a first component signal and a second magnetic field component signal. The processing circuit is connected to the sensing element, and generates an angle of the rotating structure according to the first magnetic field component signal and the second magnetic field component signal.

Abstract: A paddle wheel flow meter includes a base, a paddle wheel, an axis and a magnetic sensor. The base is capable of being embedded in a fluid pipeline, and has two lugs. The paddle wheel is disposed between the two lugs, and includes paddles, two disc wheels, two bearings and at least a magnet, wherein the disc wheels are located at two opposite sides of the paddles, the bearings are respectively disposed in the disc wheels, the magnet is disposed in at least one of the disc wheels. The axis has two ends respectively fixed to the lugs through the bearings. The magnetic sensor is disposed in the base. When a fluid in the fluid pipeline drives the paddle wheel rotating, the magnetic sensor generates an electrical signal by sensing a magnetic field change of the magnet.