High-frequency welding technology for automotive seat massage airbags is a process that uses a high-frequency electromagnetic field to heat thermoplastic materials (such as TPU) to achieve fusion. It is specifically used in the manufacture of airbag components to ensure their sealing and durability.
The core principle of this technology is to use a high-frequency electromagnetic field to cause frictional heat between material molecules, thereby achieving fusion. The self-excited oscillator inside the high-frequency welding machine generates high-frequency waves (typically 27.12MHz or 40.68MHz), forming a high-frequency electromagnetic field. When the airbag material is placed in this field, the molecules become polarized and vibrate and rub at high speed, instantly generating heat to melt the material. Combined with mold pressure, it solidifies and forms the desired shape. The entire process is rapid and involves localized heating, avoiding material damage.
The equipment operation procedure is standardized and mainly includes the following steps:
1. Power on and preheat: Connect a three-phase power supply, turn on the control box switch, and heat the vacuum tube and hot mold to the working temperature.
2. Mold installation and adjustment: Place an insulating material on the lower mold, install the upper mold, adjust the joint position and level through trial molding, and test the contact tightness using paper strips. 3. Parameter Settings: Set parameters such as delay time, high-frequency time, and cooling time according to the material thickness and shape.
4. Welding and Cooling: Place the semi-finished airbag into the mold, start the equipment for welding, and after completion, cool and set the shape. The machine head then rises to remove the product.
5. Post-processing: Perform quality control measures such as cleaning and airtightness checks.
High-frequency welding technology has several advantages and is suitable for the efficient production of automotive seat airbags. Its advantages include:
- High efficiency and speed: Short welding time (typically 1-3 seconds), suitable for automated production lines.
- Strong sealing: Uniform and dense weld joint, capable of withstanding repeated inflation and deflation pressure.
- Environmentally friendly and energy-saving: No chemical adhesives are used; energy is applied directly to the material, reducing waste.
- Precise control: Parameters are adjusted via a PLC system to ensure consistency.
This technology is widely used in the manufacturing of automotive seat ventilation bags, lumbar support airbags, and other components, and has also extended to medical, aerospace, and other fields, playing a crucial role in the safety performance of airbags.