Kenwei is a global professional manufacturer which specialized in weigher packing machines and multihead weigher machines.

The History and Applications of Multihead Weighers

2025-11-14

In the 1970s, Japan’s Ishida Company pioneered the world’s first multihead combination weigher—a cone-shaped device equipped with eight pressure sensors. Originally designed for automatically weighing and packaging green peppers, this groundbreaking machine achieved a weighing accuracy of 150±2 grams and an impressive speed of 50–60 bags per minute, marking the beginning of a true “weighing revolution.”

The History and Applications of Multihead Weighers 1

This innovation greatly enhanced production line efficiency and weighing precision, enabling automated and highly accurate portion packaging. By applying combinational mathematics through a computerized control system, the multihead weigher automatically selects the combination of weights that most closely matches the target value. Its core principle lies in the simultaneous operation of multiple independent weighing units, ensuring both speed and accuracy in dynamic weighing processes. This technology not only minimizes human error but also significantly improves production efficiency—quickly becoming a standard across the global packaging industry.

I. Development History

At one time, Ishida held nearly 80% of the global weighing and packaging equipment market. However, with continuous technological advancement and the diffusion of core technologies, a number of Asian enterprises emerged, driving both imitation and innovation. Meanwhile, manufacturers in Japan and the United States also launched products of comparable quality. This multi-directional development among global players has accelerated the evolution of multihead weighing technology, offering users a broader and more diverse range of choices.

Over the years, multihead weighers have evolved into various structures and functional types, tailored to the characteristics of different materials. For example:

Products with smooth surfaces require special feeding channels and customized vibration frequencies.
Fragile items benefit from reduced drop heights and cushioning systems.
Mixed products utilize combination weighing algorithms to achieve precise ratio control.
For sticky or moist materials such as cheese, spiral feeding paths and Teflon-coated surfaces have been developed to ensure smooth product flow.

Today, multihead weighers continue to dominate the global solid food packaging sector, standing as one of the most reliable and efficient weighing solutions available. With ongoing innovations in both technology and application, they remain at the forefront of modern packaging automation.

II. Working Principle

Although the multihead weigher has had a profound impact on the packaging industry, its fundamental working principle is relatively straightforward. Over the past fifty years, its core structure has remained stable, typically consisting of three main stages: Loading, Combined Weighing, and Discharge.

1.Loading

Materials are delivered to the dispersion table located at the center of the machine through various feeding systems. The dispersion table vibrates according to a preset frequency and amplitude, giving the product kinetic energy to overcome friction and slide along the radial troughs positioned around its edge. These troughs, which vibrate independently, direct the material into individual pool hoppers, each corresponding to one trough.

A weighing detection module beneath the dispersion table monitors the material level. When it detects insufficient product, the system automatically triggers a refilling signal. Both vibration frequency and amplitude influence the feeding rate and material flow, and must be adjusted according to the product’s friction coefficient. Experienced engineers can quickly determine the optimal settings for each material type.

In addition to radial vibration feeding, special materials may be handled using timed vibration systems or screw feeding systems, which operate on similar principles. Some models feature a ladder-type dispersion table, where multiple tiers of troughs and hoppers are arranged to accommodate materials with different flow characteristics or drop heights.

2.Combined Weighing

Material first flows into the pool hoppers and then into the weighing hoppers beneath them. Each weighing hopper operates independently. Once vibration stops at a designated interval, the pool hoppers release material into the weighing hoppers. The central control system collects all weight data and calculates, through combinational mathematics, the combination of hoppers whose total weight most closely matches the target weight. This process gives rise to the name “combination weigher.”

The History and Applications of Multihead Weighers 2

In general, the greater the number of weighing heads, the more possible combinations can be achieved—resulting in higher weighing precision and efficiency. Modern multihead weighers have evolved from the original 8-head model to configurations with 14, 20, or even 30 heads. To enhance efficiency and continuity, some models incorporate booster hoppers, which temporarily store pre-selected combinations before final discharge. In fact, the key technological differences among various manufacturers’ machines often lie in their combination selection algorithms, which determine weighing accuracy and speed.

3.Discharge

Once the optimal combination has been selected, the chosen weighing hoppers release their contents into the discharge chute, which transfers the material to the packaging machine or other downstream equipment. The emptied hoppers are then refilled as the vibratory feeders restart, allowing the next weighing cycle to begin seamlessly.

Through this intelligent combination process, the final package weight error is typically one to two orders of magnitude lower than that of single-weighing systems, dramatically improving both accuracy and consistency. The precisely weighed products are then sealed into bags, ready to enter the market—becoming the everyday goods we encounter on store shelves around the world.

III. Development and Application of Domestic Brands

In recent years, with the continuous maturation of technology and the deepening trend of globalization, Chinese manufacturers of multihead weighers have achieved significant progress through localized innovation built upon the absorption of advanced international technologies.

Among them, Guangdong Kenwei Intellectualized Machinery Co., Ltd. stands as one of the leading brands in China’s multihead weigher industry. Founded in 2006, Kenwei has specialized in the research, development, and manufacturing of combination weighing equipment. Its products are exported to over 100 countries and regions worldwide, and the company has established strategic partnerships with more than 1,500 clients.

Kenwei’s multihead weighers are widely recognized for their high stability, exceptional accuracy, and outstanding cost performance, making the company a preferred equipment supplier for numerous food production enterprises around the globe.