Follow Us
Home / IndexN / Working Principle Of Online Checkweigher


Latest News
Contact Us
    • 10th Floor, Building 5, Shin Shin Plaza, No. 2888, Jiuxin Road, Xinqiao Town, Songjiang District, Shanghai, China


    • +8618069669221

Working Principle Of Online Checkweigher

Jun 18,2022

The online checkweigher is a medium-low-speed, high precision online checkweighing equipment, which can be integrated with various packaging production lines and conveying systems. It is mainly used for online inspection of product weights, whether there are missing parts in the packaging or product weight archives.Online checkweighing has gradually become an indispensable link in modern industrial production, especially in the production process of food and pharmaceutical industries. The automatic checkweigher measures the weight of the product during the transmission of the product, and compares the measured weight with a preset weight range, automatically rejects products that do not meet the standard weight, or selects products with different weight ranges. In the designated weight class area.


Composition of online checkweigher:

The online checkweigher is generally produced by a weighing conveyor, a controller, and an in-out conveyor. Among them, the weighing conveyor completes the collection of the weight signal, and sends the weight signal to the controller for processing. The feed conveyor mainly increases the speed to ensure sufficient spacing between products. The discharge conveyor is used to transport the tested products away from the weighing area.


The working principle of the online checkweigher:

When the material is transported to the center of the weighing platform, pressure is applied to the load cell, and the sensor is deformed to change the impedance. At the same time, the excitation voltage is used to change, and a changing analog signal is output. The signal is amplified by the amplifying circuit and output to a special analog-to-digital converter, converted into a digital signal that is convenient for processing, and output to the microprocessor for operation control. According to keyboard commands and special algorithms, this result is output to the display and the item weight data is displayed. After obtaining the accurate weighing data, it will be compared with the pre-booked standard product weight. If the data is not within the standard range, it will be excluded from the production line.


The working process of the online checkweigher is as follows:

1. Front-end conveyor: convey the tested product to the weighing mechanism, on the one hand, give the object an initial speed, so that it can reach stability faster after entering the weighing mechanism; on the other hand, it can isolate and reduce the shock of the front-end material. To ensure the accuracy of measurement, and at the same time to ensure that only one product can be on the weighing platform during the work process of the checkweigher.

2. Intermediate weighing mechanism: This part is the most critical part of the entire mechanical system, and its structural design and installation accuracy directly affect the measurement accuracy of the entire system. In this part, the checkweigher will automatically obtain the weight of the product, convert it into a visual signal and output it on the large screen to complete the dynamic weighing of the object.

3. Rear-end sorting mechanism: This part is the action part of sorting, which is composed of conveying part, pneumatic valve, hopper, etc. After the controller obtains the weight signal of the product, the system compares it with the preset weight range, determines whether the product is within the standard range, and then decides whether to execute the rejection work. Complete the rejection and sorting of the unqualified part of the object. The rejection method can be set as: driving lever type,panal tumover type,air-sweeping type,push type,dropped type.

In order to facilitate everyone's understanding of the working process of the checkweigher as shown below:


When sorting products, the sorting type will vary according to the application. The principle of the mainstream rejection method is shown in the figure below:

The performance of the checkweigher:

1. The operation interface is clear and simple, intuitive reading of numbers, all data statistics function, system parameters, formula parameter settings password protection

2. It can operate online for a long time, has good repeatability, and maintains accuracy and accuracy, reduces errors, and ensures maximum production efficiency.


The automatic checkweigher is based on dynamic weighing technology, and realizes the functions of automatically transporting the products "in motion" to the weighing platform for weighing, and automatically classifying and rejecting. Under the background of "science and technology is the primary productive force", the automatic checkweigher provides the food, medical, chemical and battery industries with its advantages of full automation, high precision, 100% detection rate, simple operation and maintenance, and complete functions. The best choice to ensure quality, reduce costs and increase productivity.


Main application methods of online checkweigher:

1. Final inspection of product weight

In the final link of product production, the weight of the product is re-inspected, and unqualified products are eliminated to ensure that the weight of the products delivered meets the requirements. This helps ensure the interests of both consumers and manufacturers. Consumers will not suffer losses due to lack of weight, and manufacturers will not suffer reputation damage due to customer complaints or even complaints.

2. Feedback control

In addition to providing the weight signal of the product, the automatic checkweigher can also output a feedback signal to the packaging filling equipment according to the difference between the average weight and the nominal weight, and automatically adjust the average weight to make it consistent with the set weight. , Thereby reducing production costs.

3. Check for missing products

For products with small packages in a large package, such as a beverage box, and a large bag containing multiple small bags of products, due to equipment or personnel factors, the product will be missing. Using a checkweigher to check the weight of large packages can ensure that there will be no missing products in the large packages.

4. Sort by column

Automatic classification of products with uneven weight. For example, if the manufacturer of split chicken wants to divide chicken legs of different sizes into several weight ranges, they can use checkweighing to automatically weigh each chicken wing and send the weight signal to the PLC. The PLC drives the corresponding push based on the set range The board sends the chicken wings to the corresponding box to complete the purpose of automatic classification. The checkweigher is fast and accurate, which can save a lot of manpower.


Shanghai Shigan checkweigher provides a wealth of report statistics functions. The package quantity, total quantity, qualified quantity, qualified total, average value, standard deviation, total quantity and total cumulative data of each zone are clear at a glance. Multiple USB interfaces are available. Export the production data in the form of an Excel table at any time to help production managers grasp the production situation anytime and anywhere. Online checkweighers are widely used in a variety of industries, such as food and beverage, pharmaceutical health products, chemicals, hardware, plastics, rubber and other industries. Our company is a professional checkweigher manufacturer with its own R&D factory. If you have any needs in this regard, you can click online communication or send us an email. I believe our service will make you satisfied!