The structural composition and function of the double-speed chain line

The double-speed chain line is an automated conveying system widely used in assembly lines of manufacturing industries such as electronics, automotive, and home appliances. Its core principle lies in achieving "double-speed" operation of workpiece carriers through a special chain structure, thereby enhancing conveying efficiency and enabling precise positioning. The system primarily consists of the following key components:

- Speed-increasing chain: As the "highway" of the system, it is the core component for achieving speed-increasing functions. Its unique structure combines small rollers with large wheels (common diameter ratio of 1:3). When driven, the rollers roll along the guide rails, while the larger wheels propel the tooling plate above them at 2 to 3 times the speed of the chain itself. In terms of material, engineering plastics (such as nylon/PE) are commonly used in light-load scenarios to reduce noise, whereas steel chains are employed in heavy-load applications to enhance load-bearing capacity (single section exceeding 200kg).

- Fixture plate: Acts as the "intelligent delivery vehicle" for workpieces, directly supporting the transported materials. It not only provides physical support but is often integrated with power supply conductive rails and current-collecting wheels, enabling continuous power supply and real-time data collection (e.g., sensor signals) during the conveying process without the need for additional wiring. The fixture plate features positioning pins at its base, allowing precise alignment with workstations, with assembly errors typically controlled within ±0.5mm.

- Barrier: Acts as the "traffic police" of the production line, responsible for precisely controlling the start-stop and accumulation of tooling boards. Common types include pneumatic (fast response time, approximately 0.1 seconds) and electric (linked with PLC systems, achieving positioning accuracy of ±0.05mm), ensuring each workstation has sufficient operating time and supporting flexible takt production.

- Drive System: Serving as the "heart" of the system, it provides power and enables speed regulation. Typically composed of a frequency converter motor paired with a reduction mechanism, the conveying speed can be continuously adjusted within a range of 2–20 meters per minute to match production rhythms for different processes. The system features a high protection rating (e.g., IP65), making it suitable for harsh industrial environments such as high temperatures and dust.

- Rails and Frame: The "skeleton" of the system. Extruded aluminum alloy profiles are the mainstream rail material (accounting for over 80% of the market in 2025), offering lightweight, high stability, and corrosion resistance. Heavy-duty applications may use welded carbon steel structures. The frame provides stable support for the entire system and is often equipped with adjustable feet for fine height adjustments (e.g., ±50mm) to accommodate uneven ground.

- Auxiliary components: Include tensioning devices (maintain proper chain tension to prevent loosening), control systems (integrated PLC for automated operation and status monitoring), as well as transfer mechanisms, lifting and shifting machines, etc. (used to achieve complex handling operations such as tooling plate rotation, lifting, and more).