Conclusion
Labels on medical electronics and devices fall roughly into two types: one is traceability labels on the production line (PCBA serial numbers, QR codes, UDI barcodes), which are small in size and require stable positioning; the other is indication and compliance labels on the product itself, mostly made of synthetic paper, PET, or Mylar. Both types come in roll form and can both run on label feeders.
The difficulty lies in small size. The smaller the label, the higher the sensitivity of peeling and pick-up positions to feeding accuracy. If the fiber-optic detection and feeding position are not adjusted stably, the pick-up position will be intermittent.
Three Dimensional Facts About Small Labels
- Minimum label width: LFSID-32 and LFPANA-32 have a label width of 2–23 mm, LFJUKI-32 is 5–23 mm;
- Minimum label length: 2 mm;
- Positioning accuracy: the series has a general positioning accuracy of ±0.2 mm and an angle accuracy of ±0.5°.
These two accuracy figures rest on two mechanisms: the fiber-optic sensor determines the material position, and the touchscreen fine-tunes the feeding position.
Fiber-Optic Detection: Small Labels Especially Depend on This
The manual is very specific about the fiber-optic sensor: when the label is at the fiber-optic point, the amplifier produces a corresponding sensing value; when the working set value is greater than the sensing value and the indicator light is on, material is detected; the set value only needs to be 200 greater than the value in the no-material state.
Small labels occupy a small position on the carrier tape, so a slight offset of the fiber-optic point will cause misjudgment. When judged as having material, the feeder does not feed, and the pick-up position is empty; when judged as having no material, it will keep feeding forward.
Feeding Position and Feeding Speed Should Be Viewed Separately
- Feeding position: that is, the feed distance, adjusted according to label size. If the label curls up or is fed too much, the feeding position is too large; if the label is not fed far enough, increase the feeding position;
- Feeding speed: when increasing or decreasing, the feeding position should be fine-tuned accordingly. In cases where the placement speed is not critical, set the speed in the 30–50 range for more stable feeding;
- Feeding delay: unit 0.1 s. Used when the manipulator picks up slowly and the label is fed quickly, so it waits until pick-up is complete before feeding.
The size of traceability labels determines that they are not suitable for high-speed feeding. It is better to lower the speed in exchange for a stable pick-up position.
Peeling of Small Labels
The manual has one item written specifically for small labels: for small labels that are difficult to peel, switch the peeling blade to the side with a smaller angle.
The backing paper form also affects peeling. Sheet material and roll material have different backing papers; roll material backing paper is continuous, and the peeling blade edge is fixed at the same position, so the blade position must be re-aligned when changing material.
Reel Specifications and Material Change
The reel inner diameter follows 76.2 mm, outer diameter within 200 mm, mounted onto the label mounting shaft sleeve and limited with a retaining ring to avoid left-right swaying. When changing material, re-align two points: the guide width-limiting block is moved according to reel width, and the pressing piece height is adjusted according to label thickness.
Medical production lines are mostly small-batch with frequent changeovers. Each material change requires aligning three positions, which is the main source of downtime. The same feeder can be compatible with multiple labels, provided the material change actions are completed in order.
Sheet Material or Roll Material
If traceability labels come as pre-cut single sheets, the sheet-material version is more suitable: PLF-100 / PLF-200 / PLF-300 are graded by peeling width. For continuous roll material, use a roll label feeder. The two material forms have different backing papers and different peeling methods, so confirm the material form before selecting.
Space Saving and Multiple Columns
When machine space is tight, use the MINI series: LFSID-60M has a label width of 5–59 mm, LFSID-100M is 5–98 mm, with a shorter body, suitable for fitting into near-end stations.
When there are multiple identical labels on one board, use multi-column pick-up to split one feeding run among multiple pick-up positions, reducing the number of feeding runs.
Include These Items When Reporting Specifications
Label drawing and dimensions (width × length), material and backing paper, quantity per board, placement machine model, whether the feeder needs to give a material-present signal to the placement machine, and whether there are cleanroom or anti-static requirements on site.
Further reading: Label Feeder, How to Feed Small Labels in 3C.