A metal tube rotor flowmeter based on Hall sensor is introduced in this paper. The design method, the basic principle of detecting float displacement by Hall sensor and the basic structure and function of the output signal processing system of Hall sensor are emphatically introduced. The main characteristics of this new type of metal tube rotor flowmeter are analyzed. The actual measurement shows that the flowmeter has high accuracy and reliability. It has the characteristics of high, simple structure and intellectualization.
Volumetric flow measurement uses a fixed small volume to repeatedly measure the volume of fluid passing through the flowmeter. Therefore, there must be a standard volume of space in the volume flowmeter, which is usually called the "metering space" or "metering room" of the volume flowmeter. The space consists of the inner wall of the instrument housing and the rotating parts of the flowmeter. The working principle of the volumetric flowmeter is that when the fluid passes through the flowmeter, there will be a certain pressure difference between the inlet and outlet of the flowmeter. The rotating parts of the flowmeter (rotor for short) rotate specially under the action of this pressure difference, and the fluid is discharged from the inlet to the outlet. In this process, the fluid fills the flowmeter's "metering space" one after another, and then is continuously sent to the outlet. Under the given flowmeter condition, the volume of the measuring space is determined as long as the number of rotations of the rotor is measured. The cumulative value of the volume of the fluid passing through the flowmeter can be obtained.