How the load cell works
In principle, the load cell is a pressure sensor, but the shape is not the same, but there are usually many ways to sense, but see, use more, such as those used on the ground scale, generally eddy current type.
That is, he has an eddy current trigger winding, and then there is a sensor that senses the eddy current intensity. Because the whole weight sensor is a metal package, the eddy current is in its interior, after the pressure is deformed, the eddy current changes, and the data can be read after amplification. Then, the material that encapsulates this material is usually a rigid material. In short, it is a general metal, such as steel, but it will certainly not use very soft things. Because even steel, even if it is a few micrometers from pressure deformation, then the change of eddy current is enough to sense how much has changed in the end, and if it is soft metal, when it is heavy, it may be very easy to have problems. At least eddy current sensing pressure sensors are not made of soft metal.
The function of the load cell detection circuit is to convert the resistance change of the resistance strain gauge into a voltage output. Because the Wheatstone bridge has many advantages, such as can suppress the influence of temperature changes, can suppress lateral force interference, can easily solve the compensation problem of the load cell, etc., so the Wheatstone bridge is obtained in the load cell. A wide range of applications. Because the full-bridge equal-arm bridge has the highest sensitivity, the parameters of each arm are the same, and the influence of various interferences is easy to offset each other. Therefore, the load cell uses a full-bridge equal-arm bridge.