In the mixing and production process of polymer materials such as rubber and plastic, the internal mixer is a key equipment, and its precise material ratio directly determines the performance and quality of the product. The emergence of automatic batching technology in internal mixers has completely changed the traditional manual batching mode. Through automation control and precise measurement, it realizes the full process automation operation of various materials such as raw rubber, carbon black, and additives from storage, measurement to transportation, effectively improving production efficiency, reducing labor costs, and ensuring the stability of product quality. The following will provide a comprehensive and in-depth introduction to the composition, working principle, technical advantages, application scenarios, and development trends of automatic batching systems for internal mixers.

1、 Composition architecture of automatic batching system for internal mixer

The automatic batching system of the internal mixer mainly consists of five parts: material storage unit, precision measuring unit, intelligent conveying unit, central control unit, and auxiliary support unit. Each part works together to form an efficient and stable automated batching system.

（1） Material storage unit

This unit is responsible for storing materials to be prepared, using different storage methods based on the physical and chemical properties of the materials. For block shaped raw rubber, a three-dimensional material bin with an automatic grasping device is usually set up to facilitate the mechanical arm's grasping and conveying; Powdered materials such as carbon black and calcium carbonate are stored in a sealed negative pressure silo. The top of the silo is equipped with an efficient dust removal device to prevent dust from overflowing. At the same time, a level sensor is installed to monitor the material inventory in real time. When the material is below the set value, the alarm system is automatically triggered to prompt the operator to replenish the material in a timely manner. Liquid additives are generally stored in tanks with stirring and temperature control functions to ensure uniform and stable composition of the additives and avoid affecting their performance due to temperature changes.

（2） Precision measurement unit

The measuring unit is the core link to achieve precise batching. Diversified measurement techniques are adopted for different forms of materials: block materials are accurately weighed using a high-precision weighing platform combined with a robotic arm to achieve precise weighing of single or multiple pieces of material; Powdered materials are often measured using weight loss scales. By monitoring the real-time changes in the weight of the silo over time and controlling the speed of the screw feeder, the output of the material can be accurately measured with an accuracy of ± 0.5%; Liquid additives are measured using volumetric pumps or weighing tanks, combined with high-precision sensors, to achieve precise addition in small amounts, with errors controlled within ± 0.1%. All measuring equipment has automatic calibration function to ensure measurement accuracy during long-term use.

（3） Intelligent conveying unit

The function of the conveying unit is to safely and quickly transport the measured materials to the mixer. Select the appropriate conveying method based on the characteristics of the material: Powdered materials are conveyed using pneumatic conveying or vacuum feeding systems, and transported through closed pipelines to prevent dust leakage; Block materials are transported using belt conveyors or chain conveyors; Liquid additives are pumped through corrosion-resistant pipelines and metering pumps. During the transportation process, metal detection and foreign object interception devices are installed to prevent impurities from entering the internal mixer and affecting product quality. At the same time, the conveying pipeline adopts a quick detachable design, which is easy to clean and maintain.

（4） Central control unit

The central control unit is the "brain" of the automatic batching system, usually centered around a PLC (programmable logic controller) or industrial computer, paired with customized batching control software. The operator inputs the mixing formula through the human-machine interface (HMI), including parameters such as material type, ratio, feeding sequence, and time. The system automatically controls the discharge of material storage units, the start and stop of measuring units, and the operation of conveying units according to preset programs. During the batching process, real-time sensor data is collected at each stage, and the actual measurement values are compared with the set values. Once a deviation occurs, the equipment operating parameters are automatically adjusted to achieve closed-loop control and ensure batching accuracy. In addition, the control system also has functions such as data recording, fault diagnosis, alarm prompts, etc., which facilitate production management and equipment maintenance.

（5） Auxiliary support unit

The auxiliary support unit includes a dust removal system, an automatic cleaning device, and safety protection equipment. The dust removal system is equipped with multiple suction ports in the material storage, weighing, and conveying processes, combined with efficient dust collectors, effectively reducing workshop dust concentration and improving the working environment; The automatic cleaning device regularly cleans the conveying pipelines, measuring equipment, etc. to prevent material residue and cross contamination; Safety protection equipment such as emergency stop buttons, overload protection devices, leakage monitoring devices, etc., comprehensively ensure the safety of equipment and personnel.

2、 Working principle and process of automatic batching of internal mixer

After the operator inputs the production formula into the central control unit, the system starts the work of each unit in sequence according to the preset program. Firstly, the feeding device of the material storage unit transports the material to the precise measuring unit, which accurately weighs the material according to the preset weight or volume value. Taking powdered materials as an example, the weight loss measuring scale starts working, and the screw feeder sends the material out of the silo. At the same time, the weighing sensor monitors the weight change of the silo in real time. When the reduced weight reaches the set value, the screw feeder stops feeding. After the measurement is completed, the intelligent conveying unit transports different materials to the feed inlet of the mixer in the set order and time. Throughout the entire batching process, the central control unit continuously monitors data from each link. In case of any abnormal situation (such as excessive weighing deviation, conveyor blockage, etc.), the alarm program is immediately activated and corresponding measures are taken to ensure the smooth progress of the batching process. After the ingredients are completed, the system automatically records the relevant data of this ingredient, providing a basis for subsequent quality traceability and process optimization.

3、 The technical advantages of automatic batching in the internal mixer

（1） High precision ingredients

Through advanced sensor technology and intelligent control algorithms, the automatic batching system of the mixing machine can overcome the influence of material characteristics (such as fluidity and density changes) and environmental factors (such as temperature and pressure fluctuations) on measurement, achieve high-precision proportioning of multiple materials, effectively improve the quality stability of the mixed rubber, and reduce the product defect rate.

（2） Efficient automation

This system achieves fully automated operations from material storage, measurement to transportation, without the need for manual intervention, significantly reducing batching time and improving production efficiency. At the same time, the automatic batching system can seamlessly integrate with the mixer to achieve continuous production, effectively reducing labor costs and intensity.

（3） Flexible formula management

Support the storage and quick switching of multiple formulas, allowing operators to call different formulas at any time according to production needs, meeting the production mode of multiple varieties and small batches. The system also has a recipe permission management function to ensure the security of core recipe data.

（4） Data management and analysis

Automatically record the material type, weight, time, and other data of each batch of ingredients, and generate detailed production reports. Through data analysis, enterprises can optimize ingredient process parameters, predict equipment maintenance cycles, and provide strong data support for production decisions.

4、 Application scenarios of automatic batching in mixing machines

（1） Tire manufacturing industry

In tire production, the automatic batching system of the internal mixer accurately controls the proportion of natural rubber, synthetic rubber, carbon black, sulfur and other materials to ensure that the strength, wear resistance, aging resistance and other physical properties of the rubber mixture meet the standards, improve the quality and production efficiency of tire products, and meet the high-performance requirements of the automobile industry for tires.

（2） Rubber products industry

For the production of rubber products such as rubber pipes, sealing rings, and tapes, the automatic batching system achieves precise addition of anti-aging agents, accelerators, and reinforcing agents, improving the elasticity, weather resistance, and sealing performance of rubber products and enhancing their market competitiveness.

（3） Plastic processing industry

In the process of plastic modification production, the automatic batching system of the mixing machine accurately measures basic resins, flame retardants, antioxidants, fillers and other materials, helping enterprises produce high-performance plastic products that meet the needs of different fields, such as automotive interior parts, electronic and electrical casings, building pipes, etc.

5、 Development Trends

In the future, the automatic batching technology of internal mixers will develop towards intelligence, integration, and green direction. In terms of intelligence, artificial intelligence and machine learning algorithms are introduced to enable the system to have self-learning and adaptive capabilities, and to automatically optimize ingredient parameters based on production data; In terms of integration, it deeply integrates with the enterprise's ERP (Enterprise Resource Planning) and MES (Manufacturing Execution System) to achieve collaborative management of production planning, material inventory, and ingredient operations; Greening is reflected in reducing equipment energy consumption, reducing dust emissions, and using environmentally friendly materials. By optimizing system design and operating modes, it promotes sustainable development in the industry.