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简体中文 ### The double-deck speed chain return line that revolutionises the production process
In modern manufacturing.Space utilisation and productivityIt is the core factor that determines the competitiveness of an enterprise. The traditional single-layer assembly line often reduces the site utilisation rate due to the occupation of production space by unloaded tooling boards, whereas the double-layer speed chain return line reduces the site utilisation rate bytop and bottom separation design-The upper level carries assembly tasks and the lower level is dedicated to empty board return-enabling a true space revolution. For example, in an electronics assembly plant, the design reduces the horizontal space footprint by more than 40%, while maintaining a continuous production beat.
The unique value of this structure is that itSynchronisation solves the conflict between efficiency and layout. Workstations in the production area do not have to make room for the returning empty panels, so operators can concentrate on assembly tasks; and the independent operation of the return level avoids the interference of empty resources in the production flow. This "vertical circulation" concept is, in my opinion, one of the most practical technological breakthroughs in industrial engineering in the last decade.
Architecture and core component design
Hierarchical synergy system
- upper chain of production: Adoption2.5x or 3x speed chainThe travelling speed of the workpiece can be up to 2-3 times of the chain speed (up to 20m/min). Aluminium profile guide rail with anodic oxidation treatment, wear-resistant and straightness error ≤ 1mm/m, to ensure the positioning needs of precision assembly.
- Lower Return Channel: Empty pallets are returned to the line by means of a lower chain or belt system, running at the same speed as the upper layer but without load, reducing energy consumption.
- Shifter hubs: Core converter, consisting ofEjector cylinder + power moduleComposition. The cylinder output force is selected according to the weight of the workpiece plate + material, the jacking height precisely matches the layer spacing; the power part is driven by chain/belt, and the load capacity is up to 500kg.
Key Functional Components
- Multiplier Chain Growth Mechanism: throughDifference in diameter between roller (diameter D) and roller (diameter d)Achieve speed stacking. Speed formula: V total = V1 x (1 + D/d), 3x speed effect is achieved when D = 2d.
- Intelligent Control System: PLC-controlled photoelectric sensor system for workpiece plate in place detection (response time ≤ 0.5 seconds), blocker linkage and emergency stop protection.
- Positioning and transfer organisations: Vertical/horizontal blockers are selected according to the load; jacking translators realise material transfer across the line body, and their linear guide slides ensure vertical movement accuracy.
Technological Advantage and Production Value
Space optimisation and flexible production
- Dual-layer layout saves production line footprint for 30%-40%The new programme will be implemented in a number of industrial estates, particularly in high-rent industrial areas.
- Flexibility in increasing or decreasing the number of workstations. By adjusting the position of the blocker or the interface of the jacking machine, the line can be reorganised within one week to adapt to the introduction of new products.
Balancing efficiency and cost
- The 3x speed chain increases the conveyor speed of the workpiece plate to 3 times of the traditional chain, combined with the automatic return line of the empty plate of the refluxing laminates.Reduction of manual handling time by more than 50%.
- Modular selection of engineering plastic rollers (light duty) and steel rollers (heavy duty) reduces maintenance costs while ensuring longevity.
Stability Guarantee
- The double pitch chain design allowsSeparation of carrier rollers from conveyor rollersThis allows the system to continue to run in accumulation even if the line is partially stopped at a station.
- The drive system adopts 0.75kW motor (suitable for 50kg load) with reducer to ensure smooth starting under heavy load.
Industry application scenarios and customisation trends
Electronic and electromechanical assembly areas
- Computer mainframe/notebook production line: the upper layer completes the process of motherboard installation, heat sink assembly, etc., and the lower layer quickly reflows empty boards.
- Home appliance manufacturing: In the air-conditioning compressor assembly line, a double-deck structure carries over 300kg of engine parts while maintaining a conveyor speed of 20m/min.
Expanding Applications Across Industries
- automobile manufacturing: Transfer between engine assembly stations, jacking and panning mechanism for simultaneous collaboration of multiple line bodies.
- Pharmaceuticals and Food: Double-layer line made of stainless steel for aseptic packaging in accordance with GMP norms.
Customised design direction
- Heavy-duty scenarios (e.g. car chassis lines) use steel rollers with thickened aluminium profiles to increase the load capacity to 2000kg.
- Clean room requirements: dust-free lubrication chain + anti-static work plate, suitable for semiconductor production lines.
Key Considerations for Design and Manufacturing
Optimisation of structural parameters
- The length of single section line body ≤ 40 metres (to avoid chain sagging over 2%), the width of 250-900mm to adapt to different sizes of workpiece boards.
- The plate return machine counterweight module needs to be calculated based on the jacking load to prevent overloading of the cylinders.
Accuracy Control Points
- The number of teeth of the active end sprocket = chain pitch x times the speed ratio to ensure the precision of meshing.
- The threaded rod tensioning mechanism at the driven end needs to be independently adjusted on both sides of the chain to avoid wear and tear from partial loads.
Intelligent Upgrade
- Access to sensor data through the Industrial Internet of Things (IIoT) allows real-time monitoring of chain wear coefficients and motor load factors to predict maintenance intervals.
- Frequency conversion speed control system dynamically adjusts the conveying speed according to the production beat, and energy consumption is reduced 15%-20%.
The future potential of double-deck speed chain systems
As Industry 4.0 advances, theModularity and IntelligenceIt will become the evolution direction of the speed chain system. Recently, some companies have tried to integrate machine vision positioning in the jacking and panning machine, so that the docking accuracy of the workpiece plate is up to ± 0.1 mm. Driven by the demand for flexible manufacturing, the concept of "deformable guide" is being tested in the laboratory - real-time adjustment of the line layout through the motorised actuator. Line layout, the future or completely eliminate the physical division of the workstation.
Self-questioning on core issues
Q: Why is the "speed increase" of the multiplier chain not just an increase in chain speed?
A: The core of the multiplier chain isRoller-roller compound motion.. The chain itself travels at a constant speed, but the work plate gains additional linear speed due to roller rotation (theoretical speed increase ratio 1+D/d). This design avoids the jitter problem associated with high-speed chains, but also achieves a controllable multiplication of speeds through the physical structure.
Q: Why do companies still choose a double-layer reflow line when it is 30% more expensive than a single-layer recirculation system?
A: Its value lies inSpace costs and efficiency returns. In the case of the Shenzhen factory, for example, the 40% site saved equates to an annual rent reduction of 800,000 RMB, while the productivity improvement has shortened the payback period to 14 months.
