In the high-speed automated taping process, Jamming and Component Skipping are two critical issues affecting production efficiency. Understanding the root causes of these two faults helps engineers quickly diagnose and adjust.
1. Jamming Analysis
Jamming refers to the carrier tape being obstructed or incorrectly driven during movement, mainly manifesting in two forms:
1.1 Gear Idling & Slippage
Symptom: When loading components, the carrier tape slips off the guide gear, and the gear spins without load.
Cause: The main reason lies in the E and F dimensions (distance from sprocket hole edge to tape edge) shifting or exceeding tolerance. Tape movement relies entirely on the guide gear engaging the sprocket holes. If dimensions deviate, the tape doesn't fit tightly, leading to slippage. This is common in products with extreme B0 dimension designs (like LED carrier tapes).
1.2 Gear Resistance & Tape Breakage
Symptom: The gear has load but cannot move the tape, or moves it insufficiently, leading to tape breakage. Also, misalignment during component loading can damage the bridge between pockets, causing breakage.
Cause:
- Tight Sealing Block: The positioning sealing block of the taping machine is smaller than the outer width of the tape's B0 direction, causing excessive load when the tape passes through.
- Tape Quality: Tape material is too thick, irregularly formed, or has undercuts, causing obstruction when passing through tension mechanisms.
- Solution: For sealing block issues, lightly sand the sides of the positioning slot to eliminate load. Within allowable tolerances, modifying the mold to reduce the B0 dimension is also a solution.
2. Component Skipping Analysis
Skipping refers to components jumping out or flipping from the carrier tape pocket, occurring either before loading or after sealing:
2.1 Skipping Before Loading
Symptom: Components jump out before or at the moment of loading into the pocket.
Cause: The main reason is a mismatch between tape and component dimensions, such as Ao/Ko dimensions being too large (B0 is less relevant). Secondly, insufficient material hardness leads to deformation, affecting dimensional control. This can only be solved by changing tape specifications or increasing material hardness.
2.2 Skipping After Sealing
Symptom: Components jump out or flip inside the pocket during transport or winding after the cover tape is sealed.
Cause:
- Excessive Ko Depth: If the pocket depth Ko is too deep, components have enough space to flip during winding. Modify the mold to make Ko shallower.
- Cover Tape Compatibility: This is a more critical factor. After sealing, the cover tape must tightly adhere to the carrier tape surface. If the cover tape is unsuitable, leaving a gap between it and the carrier tape, it effectively increases the Ko depth, leading to flipping.
To thoroughly resolve this, one must ensure proper mold Ko dimensions and select a cover tape compatible with the carrier tape substrate with stable peel force.
