TL;DR
Most pallet dispenser jams come from a misaligned or damaged pallet in the stack, or debris caught in the dispenser fingers. Clear the jam from the top of the stack with the machine in safe-access mode.
What you might see
- pallet dispenser jam fault on HMI
- no pallet arriving at the build position after the dispenser cycles
- dispenser arm not completing its travel
- pallets stacked crookedly in the dispenser magazine
Likely causes
Warped or damaged pallet interlocking with the dispenser fingers and blocking release
Debris on the dispenser platform or in the finger slots preventing arm travel
Proximity sensor not confirming pallet-at-position, preventing the next dispense cycle
Low air pressure in the dispenser pneumatic circuit causing incomplete stroke
Required tools
- HMI access for fault reset and jog mode
- Compressed air pressure gauge at the dispenser manifold
- Lint-free cloth for sensor cleaning
Safety first
- Stacked pallets in the dispenser magazine are a heavy-load crushing hazard. Never reach under a pallet stack without first using the HMI manual release to safely lower and secure the stack.
- Keep feet and hands clear of the dispenser finger travel path when cycling the dispenser in jog mode.
Procedure
- 1
Acknowledge the jam fault on the HMI and put the dispenser in safe-access mode using the local key switch or E-stop pull.
- 2
Visually inspect the pallet stack from the access platform. Identify any visibly warped, broken, or misaligned pallet boards blocking the dispenser arms.[1]
Warning: The pallet dispenser magazine can hold several hundred pounds of stacked pallets. Do not reach under a partially dispensed pallet. Use the manual release function from the HMI or control panel to lower the stack safely before touching any pallet. - 3
Remove the offending pallet from the stack. Discard any pallet with broken deck boards or distorted stringers.
- 4
Clear any debris from the dispenser finger slots and the platform surface.
- 5
Check the proximity sensor that detects pallet-at-position. Clean the sensor face and verify the indicator LED responds to a test pallet.
- 6
Check the pneumatic supply pressure to the dispenser actuators. It should be at the machine design pressure, typically 80-90 psig.
- 7
Reset the fault and cycle the dispenser manually in jog mode. Confirm a pallet is placed at the build position before returning to auto.
Sources
Columbia / Okura Columbia FL / GP / HL Palletizer (Robotic / Conventional) general technical documentation, Columbia / Okura
Industrial palletizer pallet dispenser systems, jam clearing and maintenance, general material handling references (general)
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