Application of Lingchen PLC high-speed latch trigger function in rotary material detection

In rotary automated equipment, the continuous high-speed movement of materials poses stringent challenges to the real-time performance and accuracy of the control system. Leveraging the superior high-speed latching and triggering capabilities of its PLC products, Lingchen Technology has successfully applied this technology in a high-precision appearance inspection system, achieving stable and efficient rotary material inspection and reshaping production efficiency with cutting-edge technology.

Project Requirements Analysis

This project requires the equipment to accurately detect and sort materials while the turntable is running at high speed, with an overall cycle time not exceeding 1 second. Its core control requirements focus on the turntable scenario:

High-speed synchronization: The DD motor drives the turntable via the EtherCAT bus, requiring the PLC to follow the high-speed pulse signal in real time.

Instantaneous latching: When material passes through the fiber optic sensor, the PLC needs to lock its precise position within microseconds.

Precise triggering: Based on the latch position and preset offset, the camera and air valve are triggered with millisecond precision during movement.

Data collaboration: Real-time communication with vision and MES systems ensures accurate matching of detection results and execution actions during high-speed operation.

Lingchen's Solution and Implementation Process

Lingchen Technology uses the Lingchen LC1508 series PLC as the control core, combined with Lingchen 10-inch HMI, multi-channel input/output modules, and distributed IO, to build a hierarchical and responsive electrical control system.

1. Hardware configuration

PLC: Lingchen LC1508
HMI: Lingchen 10-inch Touchscreen
Input Module: Lingchen LC1406 × 3
Output Module: Lingchen LC2486 × 3

2. Implementation process

1. Position Locking and Triggering: After the product is loaded and aligned by the vibratory feeder, a fiber optic sensor triggers the PLC for high-speed position locking. The PLC then triggers a camera to take a "flying shot" at a precise position based on a preset offset.

2. Data Interaction and Judgment: After the vision system takes a picture, the image is uploaded to the MES for AI judgment. The judgment result (NG information) is fed back to the PLC via Modbus TCP.

3. Intelligent Sorting Execution: The PLC buffers and matches the product position information with the judgment result (buffer capacity 100 pieces). When the product reaches the air blowing station, the PLC accurately blows the NG product into the corresponding hopper through high-speed comparison output.

3. Solution Highlights

The core competitiveness of this solution lies in the Lingchen PLC's ability to process high-speed signals and control complex logic:

High-speed latching function area: Integrates encoder high-speed counting, photoelectric probe instantaneous latching, and material interval anti-shake algorithm to ensure stable and reliable signal capture under high-speed operation.

Precise triggering function area: Employs a "position latch + offset + queue management" mechanism, achieving microsecond-level accuracy in camera triggering and blowing actions through hardware-level comparison output, eliminating missed shots or false blows.

Advanced data processing mechanism: Features data deduplication, dynamic ID sorting, transmission delay monitoring, and automatic position offset compensation, ensuring the consistency and reliability of the system during long-term continuous operation.

Practical verification shows that this program logic, based on the LC1500 series PLC, operates stably, "flying shot" triggering is accurate, and the queue management function effectively solves the industry problem of asynchronous data flow matching under high-speed continuous production.

Summary and Outlook

The solution provided by Lingchen Technology not only perfectly met the customer's extreme requirements for inspection speed, accuracy, and reliability, but also demonstrated the comprehensive strength of its PLC products in high-speed counting, real-time position comparison, multi-protocol communication, and complex logic processing. The successful implementation of this case provides a replicable technical model for appearance inspection and similar automated equipment requiring high-speed synchronous control. In the future, Lingchen Technology will continue to focus on innovation and breakthroughs in core industrial control technologies, committed to providing a more powerful and intelligent "control brain" for a wider range of industrial scenarios, and driving China's intelligent manufacturing towards higher efficiency and higher quality.