Weighing sensor: the core force of accurate measurement

Weighing sensor: the core force of accurate measurement

In many fields of industrial production, commercial trade, and daily life today, weighing sensors play an indispensable and critical role. From precise weighing of raw materials and finished products on factory assembly lines, to monitoring of truck load in logistics transportation, and to precise measurement of electronic scales in commercial retail, the presence of weighing sensors is ubiquitous, and their importance is self-evident.

1、 Working principle

The core working principle of a weighing sensor is based on measurable changes in certain physical characteristics that occur with external forces. The most common is strain gauge weighing sensors, which utilize the strain effect of metal or semiconductor materials. When external force is applied to the elastic element of the sensor, the elastic element will deform, and the strain gauge attached to it will also deform, resulting in a change in the resistance value of the strain gauge. By measuring the change in resistance value and undergoing specific circuit conversion and signal amplification processing, an electrical signal proportional to the applied external force can be obtained, thereby determining the weight of the object.

For example, in an electronic car scale, when the vehicle is parked on the weighing platform, the weighing sensors below the platform will undergo small deformations due to the weight of the vehicle. This deformation is converted into electrical signals, which can be processed and converted by the instrument to accurately display the vehicle's load value. Its accuracy can reach tens of kilograms or even higher, depending on the accuracy level of the sensors and the design of the entire weighing system.

2、 Type and Characteristics

Resistance strain type weighing sensor

This is currently the most widely used type. It has the advantages of simple structure, high accuracy, and strong reliability. It can adapt to various harsh industrial environments and has a wide measurement range, ranging from a few grams to hundreds of tons, suitable for various scenarios from laboratory precision weighing to large-scale industrial weighing. However, its disadvantage is that it is sensitive to temperature changes and requires effective temperature compensation measures to ensure measurement accuracy under different temperature conditions.

Capacitive weighing sensor

Measuring weight based on changes in capacitance has high accuracy and good dynamic response characteristics, good stability, and is relatively less affected by environmental factors such as temperature and humidity. Commonly used in situations where high precision is required and environmental conditions are complex, such as ingredient weighing systems in industries such as pharmaceuticals and chemicals. However, the cost of capacitive sensors is relatively high, and the circuit design and debugging are also complex.

Piezoelectric weighing sensor

Using the charge changes generated by piezoelectric materials under stress to measure weight has advantages such as fast response speed and good high-frequency characteristics. It is particularly suitable for dynamic weighing and impact force measurement, such as on material sorting lines in industrial production, which can quickly and accurately measure the weight of materials passing through at high speeds. However, piezoelectric sensors have poor low-frequency performance and are not suitable for measuring static or slowly changing loads. Their output signals are weak and require high gain amplifiers.

3、 Application Fields

Industrial manufacturing

In industries such as steel, non-ferrous metals, and building materials, weighing sensors are used for measuring raw materials entering and leaving the factory, controlling ingredients during the production process, and inspecting the quality of finished products. For example, in the process of cement production, precise weighing sensors can strictly control the proportion of raw materials, ensure stable quality of cement products, improve production efficiency, and reduce production costs.

Logistics transportation

Whether it is road transport trucks, railway transport trucks, or sea freight containers, weighing sensors are widely used for weighing vehicles and goods to ensure transportation safety, avoid overloading, and provide accurate data basis for logistics billing. At the container terminal of the port, the weighing sensors on large scales can quickly and accurately measure the weight of fully loaded containers, with errors controlled within a very small range.

Commercial Retail

As the most common weighing device in the commercial retail field, the core component of electronic scales is the weighing sensor. From vegetable and fruit scales in supermarkets to precision scales in jewelry stores, weighing sensors with different accuracies and ranges meet the weighing needs of various products, ensuring fair and just transactions, and providing important data support for inventory management and sales statistics of merchants.

4、 Development Trends

With the continuous advancement of technology, weighing sensors are also constantly developing and innovating. On the one hand, the accuracy and reliability of sensors will be further improved, and the application of new materials and manufacturing processes will enable sensors to achieve more accurate measurements in more complex environments. For example, strain gauge materials improved by nanotechnology are expected to significantly enhance the sensitivity and stability of sensors.

On the other hand, intelligence and networking will become important development directions for weighing sensors. Through the built-in microprocessor and communication module, sensors can achieve functions such as self diagnosis, automatic calibration, data storage, and remote transmission, making it convenient for users to obtain weighing data anytime and anywhere, and seamlessly integrating with other production management systems to achieve automation and intelligent management of industrial production and commercial operations, providing strong support for enterprises to enhance competitiveness and economic benefits.

As a key component in modern measurement technology, weighing sensors play a crucial role in various fields. With the continuous breakthroughs in technology and the continuous expansion of application scenarios, weighing sensors will inevitably usher in broader development prospects and contribute greater strength to promoting the development of various industries.