Device and method for measuring long stroke displacement based on Hall effect

Abstract

The invention belongs to the technical field of physical parameter measurement and relates to a device for measuring long stroke displacement based on the Hall effect. The device comprises a single chip microcomputer, a constant current source, a signal processing circuit, an analog-to-digital converter and a sensor array, wherein the sensor array is at least one group of linear hall sensors; each group of the linear hall sensors are uniformly and linearly arranged on a PCB (Printed Circuit Board); the space between the adjacent linear hall sensors is not less than the size of a magnet on a magnetic float in the arrangement direction of the sensor array; the differential outputs of the linear sensors are multiplexed with two differential voltage signal transmission lines through an n-channel analog multiplexer; the two differential voltage signal transmission lines are connected with an input interface of the signal processing circuit; the two adjacent PCBs are connected through an expansion interface; and each group of the linear hall sensors are powered by one same constant current source in a time sharing manner. The device has the advantages of low power consumption, fewer adopted devices, convenience in maintenance and lower cost.

Description

technical field [0001] The invention belongs to the technical field of physical parameter measurement, and relates to a Hall effect displacement measuring device and a measuring method, in particular to a Hall displacement measuring device and a measuring method for long-stroke displacement measurement through a linear Hall sensor. Background technique [0002] At present, the transmitter part of the magnetic float level gauge uses a reed switch sensor. Some technical parameters of the transmitter of the magnetic float level gauge: [0003] Liquid density: >0.4g / cm3, [0004] Maximum range: 0-6m, [0005] Resolution: ±1cm, [0006] Signal transmission mode: (4-20) mA (two-wire system). [0007] Magnetic float level gauge is a kind of liquid level instrument that has certain requirements for measurement accuracy (resolution: ±1cm), but the requirements are not too high, and its price is relatively moderate. If higher accuracy is required, such as ±1mm accuracy, other ...

AI Technical Summary

Problems solved by technology

The switch-type Hall sensor is an active device, coupled with the auxiliary circuit, the measurement range will not be able to realize the thin strip device

[0012] 3. Using a switch-type Hall sensor, as the measurement length increases, the circuit complexity increases exponentially, and its low-power measurement method will be meaningless

[0013] 4. Using a switch-type Hall sensor, as the measurement length increases, the complexity of the circuit increa

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