Lingchen PLC Empowers Airplane Box Folding Machine Upgrades
In the packaging industry, airplane box folding and forming is a critical step in post-packaging operations, widely used in food, pharmaceutical, cosmetic, and 3C electronics packaging scenarios. Traditional folding solutions often use PTP (point-to-point) control, where bending actions start and stop abruptly, causing high impact, uneven creases, and low success rates. Additionally, switching between different box types requires reprogramming and debugging, which is time-consuming and demands high technical expertise, severely impacting production efficiency and market responsiveness.
The customer's original folding process used PTP control, with high impact and lengthy changeover times. The customer clearly requested an upgrade from PTP to a cam-based solution to increase production capacity while enabling workers to easily adjust parameters for different box types and achieve rapid production.
Lingchen Technology, with over 20 years of industrial automation expertise, has successfully delivered a complete solution for airplane box folding machines, centered on the Lingchen PLC + electronic cam, helping customers achieve breakthroughs in both efficiency and quality.
Airplane Box Folding Process Flow
The airplane box (also known as courier box or postal box) gets its name from its shape resembling an airplane when unfolded. It is one of the most widely used box types in the packaging industry. The equipment is mainly used for folding and forming airplane boxes, consisting of two major parts: the loading section and the folding section.
Loading Section
The paper box loading system uses a continuous feeding cycle process, divided into three workstations:
- Pick-up station: Suck paperboard from the magazine
- Shaking station: Separate stuck paperboards through shaking action; the system supports custom settings for shake cycle count via HMI to adapt to different paperboard hardness and adhesion levels
- Placement station: Place paperboard onto the folding station
Action logic interlock: After the single-box placement process is complete, the X-axis transfer mechanism must return to the pick-up origin before the system allows the folding process to start, ensuring interlocking between stations and eliminating interference risks.
Parallel front/rear processes: While the folding station performs folding actions, the front-end loading suction mechanism simultaneously completes the pre-grasping of the next paperboard and stands by. Once the current box folding is complete, the pre-grasped paperboard is immediately transferred to the folding station, achieving parallel processing without waiting and significantly improving overall continuous production efficiency.
Folding & Forming Section
The airplane box folding process consists of multiple precise steps, performed in the following sequence:
- ① Small flap pre-folding: Front and rear small flaps are folded along preset crease lines to form a 90° vertical state with the front/rear main folds, completing small flap pre-positioning.
- ② Front/rear fold wrapping: Front and rear main folds are bent inward 90°, simultaneously enclosing the pre-folded small flaps inside the box body.
- ③ Left/right folds and ears synchronous pre-folding: Left and right main folds are bent inward 90°, simultaneously driving the side ears to pre-fold to the preset angle.
- ④ Ear locking bottom engagement: Both side ears are fully pressed and bent inward, engaging the ear snap structure with the corresponding slots on the box bottom, completing bottom locking and forming.
The entire folding process involves multiple actuators including left/right small flap shafts, front/rear fold shafts, left/right fold shafts, left/right pressing shafts, and left/right locking shafts. Each axis must coordinate according to specific timing and phase relationships, placing extremely high demands on the control system's synchronization accuracy and trajectory smoothness.
Lingchen Technology Solution
Hardware Configuration
This solution uses the Lingchen PLC as the core controller, managing the folding servo and encoder via EtherCAT bus, while remaining compatible with the machine's existing peripherals. Lingchen GWS series cabinet IO modules offer high stability and convenient network cabling, suitable for distributed industrial control scenarios, significantly saving system integration time and cost. The Lingchen HMI enables parameter setting, cam curve monitoring, recipe management, and alarm display.
① Virtual Master Axis + Electronic Cam Synchronization
A virtual master axis is built inside the PLC, serving only as a motion reference for the folding mechanism without modifying other machine structures. An exclusive electronic cam curve is programmed according to the folding process, with bending and pressing axes following the virtual axis phase synchronously. With smooth motion algorithms, the entire acceleration/deceleration process is seamless, completely eliminating rigid impact.
② Zoned Motion Control
The controller only enables virtual axis, electronic cam, and multi-axis synchronization functions for the folding unit, while other mechanisms retain their original control logic. New and old programs coexist, reducing upgrade costs and risks. The EtherCAT bus architecture achieves zoned management, collaborative efficiency, and high-speed command/data interaction.
③ Multi-Recipe Cam Curve Application
Multiple cam curves for different box types are pre-programmed and saved as recipes. Operators can switch with one touch via the touchscreen without reprogramming. Trajectory buffering optimizes key positions for direction changes and end bending, preventing speed spikes that could damage the box. The fixed preset cam trajectory ensures consistent forming standards across every batch.
④ Closed-Loop Position Feedback Logic
Encoders collect actual folding axis positions in real time and compare them with the electronic cam theoretical positions, ensuring the axes follow the preset trajectory precisely. Long-term position stability and consistent folding accuracy are maintained.
Solution Value
Quality Leap
Specially optimized folding process completely eliminates defects such as wrinkles, cracks, and uneven bending caused by point-to-point control. Smooth buffering at bending endpoints replaces the abrupt start/stop mode, optimizing end bending trajectories and reinforcing box shape to prevent spring-back and loose boxes. Finished box quality is significantly improved, reducing scrap and rework costs.
Capacity Breakthrough
Eliminates waiting time at the folding station, ensuring a continuous and smooth folding process. The equipment can run at full rated speed. Parallel front/rear processes mean the loading mechanism pre-grasps the next paperboard while folding is in progress, delivering it immediately upon completion. This greatly enhances overall continuous production efficiency, fully releasing machine uptime and overall production capacity.
Cost Optimization
Box type switching is completed with one touch, drastically reducing professional debugging time. Only the folding unit control is upgraded with minimal hardware changes, keeping overall investment controllable. Multi-recipe cam curve application eliminates reprogramming, significantly shortening commissioning cycles.
Maintenance Simplification
Folding axis loads are smooth, reducing mechanical component wear and failure frequency. The clearly zoned system simplifies troubleshooting, enabling basic operators to handle routine maintenance and reducing long-term upkeep costs. Closed-loop position feedback ensures long-term position stability and consistent folding precision.
Conclusion
The airplane box folding machine is a critical piece of post-packaging automation equipment in the packaging industry. Its control precision and operational efficiency directly determine packaging quality and production capacity. Traditional PTP control starts and stops abruptly, causing high impact, low precision, and difficult changeovers. Lingchen Technology, with the Lingchen PLC at its core, has successfully upgraded the airplane box folding process from PTP mode to electronic cam control through innovations such as virtual master axis + electronic cam synchronization, EtherCAT high-speed bus, one-touch recipe switching, and closed-loop position feedback. This comprehensively solves quality issues, eliminates action waiting time, enables one-touch changeover, and significantly improves machine uptime and production flexibility.
This solution's multi-dimensional value—quality leap, capacity breakthrough, cost optimization, and maintenance simplification—has been fully validated at customer sites. In the future, Lingchen Technology will continue to deepen its presence in industrial automation, focusing on packaging, 3C, semiconductor, new energy, and other industries, providing more comprehensive PLC products and motion control solutions to empower China's intelligent manufacturing transformation and upgrade, contributing to the high-quality development of China's manufacturing industry.
About Lingchen
Suzhou Lingchen Collection Computer Co., Ltd., established in 2006, is an enterprise with the business philosophy of "creating value for customers and win-win cooperation". We provide customers with core components and system solutions for industrial computers, motion control, test and measurement, machine vision, robots, and other automation equipment. Currently, Lingchen has two wholly-owned subsidiaries: Suzhou XunYa Automation Technology Co., Ltd. and TOKK Robotics (Suzhou) Co., Ltd., engaged in robot sales and R&D, production, and sales of linear transmission products respectively. With outstanding performance in specialization, refinement, differentiation, and innovation, the company was successfully awarded the title of National "Little Giant" Enterprise for Specialization and Innovation by the Ministry of Industry and Information Technology in 2025, marking a new stage of development. We will continue to promote the development and innovation of China's intelligent manufacturing industry.
In the hierarchical automation control network, Lingchen Technology covers all products at the device layer, control layer, and information layer.
01 Industrial Computers
Lingchen industrial chassis, with industrial-grade rugged structure, excellent heat dissipation and dust-proof design, provides comprehensive physical protection for critical computing cores, ensuring long-term stable operation in harsh industrial environments such as vibration, dust, and wide temperature range.
02 Embedded Industrial Computers
Lingchen embedded industrial computers, with compact and rugged industrial design, integrate high-performance computing, rich I/O interfaces, and wide temperature/power adaptability. Tailored for embedded scenarios such as machine vision, edge computing, and automation equipment, they provide a stable and reliable intelligent core in limited spaces, empowering intelligent manufacturing and IoT applications.
03 Motion Control Card
Lingchen motion control cards can control up to 32 motion axes, simultaneously supporting up to 512 DI points and 512 DO points, with a maximum bus communication cycle up to 250µs. Motion support includes single-axis relative motion, absolute motion, jog motion, driver homing; multi-axis interpolation; multi-axis point table motion; electronic gearing, and more.
04 LMC Series Motion Controller
Lingchen LMC series motion controllers, based on an open hard real-time kernel (jitter < ±0.3µs), fundamentally solve the non-real-time pain points of traditional Windows platforms, ensuring determinism and immediate response for multi-axis commands. Installation is extremely convenient—just a single network cable—and through efficient asynchronous communication technology, up to 12 axes of motion commands can be synchronized and controlled within 1 millisecond.
05 NAC Series High-Performance Motion Controller
Lingchen NAC controllers, with powerful bus expansion capabilities, support 4 EtherCAT masters, enabling precise control of up to 256 axes and 4096 I/Os per station. Its motion control functions are comprehensive: not only basic point-to-point, linear and circular interpolation, but also five-axis interpolation, trajectory spline smoothing, dynamic coordinate systems, and other advanced features; integrated vibration suppression, soft landing, and high-precision position compare output, combined with 8 independent interpolation systems and continuous interpolation capabilities, meet complex trajectory and high-speed synchronization needs. The development environment is open and flexible, supporting C++, C#, Python, and other languages, and allows direct programming within the real-time system, significantly improving integration and debugging efficiency.
06 PLC Motion Controller
Lingchen PLC controllers strictly comply with PLCopen specifications and IEC-61131-3 international standards, combining high performance, compact size, and modular design, with easy development and flexible deployment. Widely applicable to automation equipment and production line systems in 3C, lithium battery, packaging, printing, and other fields, and can be extended as network communication nodes in combined production lines such as logistics, automotive, and consumer goods, meeting internal/external network isolation, high-speed bus communication, and real-time data processing requirements, providing a stable and reliable control core for various industrial scenarios.
07 Industrial Network Card
Lingchen industrial network cards are designed for harsh industrial environments, with 10/100/1000Mbps auto-negotiation capability, providing stable and reliable high-speed network connections. Featuring anti-interference, surge protection, and wide-temperature operation, they are widely used in motion control, machine vision, and automation systems. The product adopts a flexible mounting design (standard full-height bracket, optional half-height bracket), enabling broad integration into various intelligent manufacturing equipment and industrial networks.
08 IO Modules
Lingchen Technology provides a full range of IO module solutions, flexibly meeting diverse industrial automation needs.
- LC/LD Series Expansion IO Modules: Support EtherCAT, Profinet, Ethernet/IP, Modbus TCP, and other protocols, flexibly expand digital, analog, temperature, pressure, pulse acquisition modules, widely used in 3C, lithium battery, semiconductor, automotive, medical, and other fields.
- MINI Series IO Modules: Compact size, high real-time performance, covering digital IO, analog IO, temperature modules, communication modules, etc., suitable for control and data acquisition scenarios with high requirements for space and real-time response.
- GWS Series Cabinet IO Modules: High stability and convenient network cabling characteristics, suitable for distributed layouts, significantly saving system integration time and cost.
The full product line is committed to providing reliable, easily integrated, and multi-scenario adaptable IO module support.
