The load cell is a device that converts the quality signal into a measurable electrical signal output. Whether it can be used normally and correctly is related to the reliability and safety of the whole weighing device. This product can be divided into different types in terms of the basic concepts and evaluation methods of the main technical indicators. Today, I will show you which types of products and their characteristics.
Ⅰ. Photoelectric Type
Including grating type and code disk type. The grating sensor uses the moire fringe formed by the grating to convert the angular displacement into the photoelectric signal. The number of moire fringe can be calculated by using the photoelectric tube, conversion circuit and display instrument. The code disk of the code disk type sensor is a transparent glass installed on the scale shaft, on which black and white code is written according to a certain coding method. Photoelectric sensor is mainly used for electromagnetically combination scale.
Ⅱ. Hydraulic Type
Under the action of the gravity P of the measured object, the hydraulic oil pressure increases, and the increase is proportional to P. The mass of the measured object can be determined by the increase of the measured pressure. The hydraulic sensor has the characteristics of simple structure, firmness and large measuring range.
Ⅲ. Capacitive Type
The working principle of the capacitive resonator is proportional to the oscillation frequency f of the capacitive oscillation circuit and the distance d between the plates. By measuring the change of frequency, the mass of the measured object on the bearing platform can be obtained. Capacitive sensor has the advantages of high impedance, low power consumption, fast dynamic response and simple structure. Strong adaptability and low cost.
Ⅳ. Electromagnetic Force Type
Electromagnetic force type uses electromagnetic force to balance the load on the platform. The accuracy of the electromagnetic force sensor is high, up to 1/2000~1/60000, but the weighing range is only tens of milligrams to 10 kilograms. Magnetic pole change The ferromagnetic element undergoes mechanical deformation under the gravity of the measured object, and the internal stress produces and causes the change of magnetic permeability, thus causing the induced voltage of the secondary coil around the ferromagnetic element is also change. The sensor has low accuracy and is suitable for large-tonnage weighing operation.
Ⅴ. Elastic Element Type
The natural vibration frequency of the elastic element is proportional to the square root of the force. By measuring the change of natural frequency, the force of the measured object on the elastic element can be calculated, and the mass of the elastic element can be calculated. The gyro ritual sensor has the characteristics of fast response time, no lag, good temperature characteristics, small vibration impact, high frequency measurement accuracy, etc. It is mainly composed of elastic element, resistance strain gauge, measuring circuit and transmission line.
Ⅵ.Plate-ring Type
The structure of the plate-ring load cell has the advantages of clear stress streamline distribution, high output sensitivity, elastic body as a whole, simple structure, stable stress state, and convenient to process.
Post time: Feb-20-2023