Mechanical Automatic Scrap Ejector for Stamping Dies

A Simple Kaizen: Harnessing die motion for automatic scrap ejection

In sheet metal stamping, scrap falling and accumulating under the lower die is a persistent technical challenge that requires a reliable solution.

If not cleared in time, accumulated scrap can jam the die, dent or deform the workpiece, and create safety hazards when operators intervene with manual tools.

Understanding this challenge, Hirota Precision Vietnam has implemented a Kaizen solution: installing a mechanical automatic scrap ejection system directly on the press die.

Operating Principle

The ejector operates without electricity, sensors, or compressed air, making full use of the die’s own opening and closing stroke:

• Leveraging the press stroke: As the upper die descends, a cam block mounted on the upper die engages the slider of the drive assembly on the lower die.
• Converting to horizontal motion: The drive assembly converts the vertical pressing force into a horizontal pushing force, acting directly on a steel plate embedded inside the lower die area.
• Rhythmic scrap displacement: With each press stroke, the steel plate advances a preset distance, pushing the scrap outward step by step with every cycle.
• Automatic discharge and reset: Scrap is continuously pushed out from under the die. As soon as the upper die rises, a return spring pulls the steel plate back to its original position, ready for the next stroke.

Practical Benefits

• Occupational safety: Completely eliminates the need for operators to reach into the hazardous area under the die with their hands or tools.
• Higher productivity: Scrap is discharged automatically and continuously in sync with the press rhythm, eliminating line interruptions and cleaning downtime.
• Energy saving & cost optimization: Operating 100% on the press’s mechanical force, the ejector requires no additional electricity or compressed air.
• Die protection & product quality: The area under the die stays clear, preventing scrap buildup from deforming or denting component surfaces.

Conclusion

At Hirota Precision Vietnam, every Kaizen improvement, big or small, serves a single goal: optimizing production processes, ensuring worker safety, and delivering the highest precision and quality to our customers.