What is weighing load cell？

The load cell can convert the load acting on it into a measurable (analog load cell or digital load cell) output. The output of the device is proportional to the applied force or load. The following editor will introduce the types and working principles of load cells:

1: The type of load cell

There are many types of load cells, including semiconductor, hydraulic (or hydrostatic), pneumatic, piezoelectric, and vibrating wire load cells. The design of load cells can be distinguished by two methods, one is the type of output signal generated, such as pneumatic, hydraulic or electrical, and the other method is to distinguish by detecting load or weight, such as bending, shearing, compression and The value of the pulling force, etc.

In order to meet various purposes in R&D and industrial applications, load cells can take many forms, but most designs today use strain gauges containing foils or semiconductors as sensing elements. Among them, the foil-containing strain gauge is the most extensive load cell design, and the semiconductor strain gauge has a smaller mode range, and its advantage is that it can provide a larger specification factor to produce a larger output under the same given stress . The semiconductor strain gauge has a simple structure and includes a proof ring and a precision displacement sensor. The proof ring is a calibrated metal ring for load measurement, and the precision displacement sensor can measure its movement. It is precisely because of this characteristic that semiconductor strain gauges are often used in the design of miniature load cells.

2:The working principle of the load cell

The working principle of the load cell is to realize the conversion through the physical deformation of the strain gauge. The strain gauge is connected to the Hui through four strain gauges (full bridge), two strain gauges (half bridge) or one strain gauge (quarter bridge). Stone bridge circuit and combine it with the load cell structure. The load cell itself is glued to the beam or structure, and when force is applied, the beam or structure will deform. In most cases, four strain gauges are used to obtain maximum sensitivity and temperature compensation. Two gauges are usually in tension and the other two gauges are in compression, and they are wired through compensation adjustments. The Wheatstone bridge circuit will also be equipped with other bondable resistors to compensate for the effect of temperature on the zero-load or no-load signal and sensitivity. A complete Wheatstone bridge requires a stable DC power supply to excite the circuit, usually 5Vdc or 10Vdc, but its output value can be set between 1Vdc and 18Vdc.

At present, strain gauge load cells have gradually developed into low-cost and high-precision instruments, which are becoming more and more popular.