Printing Press Knowledge Sharing: Feeder Chapter - Core Technology for Precise Paper Feeding
I. What is a Feeder?
A Feeder, also known as a paper feeding device or feeding mechanism, is the core component at the forefront of a printing press. It is responsible for precisely separating the top sheet from the paper stack and smoothly transporting it to the printing unit. As the "throat" of the printing press, the performance of the Feeder directly determines printing efficiency and quality.
II. Core Functions of the Feeder
Paper Separation
Paper Separation Device: Utilizes a combination of separation suckers and blowers to ensure only one sheet is picked up at a time.
Double Sheet Detection: Photoelectric or mechanical detection prevents multiple sheets from entering simultaneously.
Paper Transport
Transport Mechanism: Uses feed belts or a vacuum transport system to accurately deliver sheets to the positioning device.
Variable Speed Control: Automatically adjusts the feeding rhythm according to the printing speed.
Paper Positioning
Front and Side Lay Guides: Ensure the sheet reaches the precise position.
Positioning Accuracy: Typically requires an error ≤ 0.1mm.
III. Main Types of Feeders
Traditional Feeder
Characteristics:
Mechanical transmission structure.
Suitable for low-speed printing (≤ 8,000 sheets/hour).
Simple maintenance but lower efficiency.
High-Speed Feeder
Characteristics:
Pneumatic and electric hybrid drive.
Suitable for high-speed printing (≥ 12,000 sheets/hour).
Equipped with intelligent detection systems.
Hybrid Feeder
Characteristics:
Adapts to different paper weights (80-600 g/m²).
Automatically adjusts blowing and suction air volume.
Intelligent pre-pile loading function.
IV. Analysis of Key Feeder Components
|
Component Name |
Function Description |
Maintenance Points |
|
Separation Suckers |
Picks up the top single sheet |
Regularly replace rubber rings |
|
Blowing Device |
Loosens the upper sheets of the pile |
Keep air passages clear |
|
Paper Stack Pedal |
Controls the height of the paper stack |
Check spring pressure |
|
Feed Rollers |
Transports the separated sheets |
Clean surface wear |
|
Detection Sensors |
Monitors paper position |
Regularly calibrate sensitivity |
V. Common Feeder Faults and Solutions
Double or Multiple Sheets
Cause: Excessive blow air volume, improper sucker adjustment.
Solution: Reduce blow air volume, adjust sucker height.
Skewed Sheet Feeding
Cause: Uneven feed belt tension, unbalanced suction.
Solution: Adjust feed belt tension, check air paths.
Missed Sheets or Sheet Breakage
Cause: Insufficient blow air volume, paper sticking.
Solution: Increase blow air volume, check paper humidity.
VI. Daily Maintenance Guide for Feeders
Daily Maintenance
Clean blow and suction air pipes.
Check wear and tear on various components.
Calibrate detection sensors.
Weekly Maintenance
Clean feed belts and rollers.
Check the sealing of air paths.
Lubricate moving parts.
Monthly Maintenance
Comprehensive check of mechanical wear.
Calibrate positioning accuracy.
Replace wearing parts.
VII. Considerations When Purchasing a Feeder
Match Printing Speed: Ensure the Feeder's maximum speed ≥ the printing press's rated speed.
Paper Adaptability: Confirm the range of paper weights it can handle.
Detection System: Choose high-precision double sheet and missed sheet detection functions.
Brand Compatibility: Ensure compatibility with existing printing presses.
VIII. Technology Development Trends
Intelligent Upgrades
Automatic Pre-pile Loading System: Reduces preparation time.
Intelligent Air Volume Regulation: Automatically optimizes based on paper characteristics.
Remote Diagnostic Function: Monitors operating status in real-time.
Green and Environmental Protection
Low Energy Consumption Design: Optimizes pneumatic system energy use.
Noise Reduction Technology: Improves the working environment.
IX. Practical Operation Tips
Quick Adjustment Steps:
Set baseline air volume according to paper weight.
Adjust separation sucker height (3-5mm from the paper pile).
Set blower angle (usually 15-30°).
Calibrate detection device sensitivity.
Fault Troubleshooting Mnemonic:
"Check air first, then machine, see if sheets are aligned right.
Sensors need calibration, regular maintenance is the base."
X. Conclusion
As the "first gateway" of the printing press, the stability of the Feeder is directly related to the overall machine's operating efficiency. Mastering the working principles and maintenance essentials of the Feeder can not only reduce downtime but also significantly improve print quality. It is recommended that operators maintain detailed maintenance records, regularly participate in professional technical training, and continuously improve equipment management skills.
