The Challenge

A research and development company approached Wrabacon looking to start a new product line. The process would involve a stack of trays being presented to the system, upon which these trays would need to be denested to be individually filled with product. Following this, the filled trays would need to be restacked to the same height. With each filled tray averaging about 45 pounds, and the stacks consisting of 24 trays apiece, it was extremely clear that an automated system was the only solution that would be efficient and ergonomically safe. 


The Solution

Wrabacon custom designed and manufactured a tray stacker/denesting system that handles trays of product. The trays sit on modified pallets, and the system denests and stacks trays at a rate of 6 per minute.  
 
Here’s how it works: There is one cell for each of the denest and stack stations. Operators manually load full pallets, filled with product, onto a pallet conveyor. The first pallet moves into position and the system starts by raising the entire stack of trays off the pallet, and up to the cross-conveyor height. Cylinders extend — to lift the top tray out of the stack — and a cross cylinder pushes the tray, from the stack onto the cross-conveyor. After the tray has been denested, the lifting mechanism indexes up — one pitch. The second tray is then denested, and pushed onto the cross conveyor. Meanwhile, the first tray moves down the conveyor, and the cured product is taken out. The empty tray then travels downstream, where it is stopped and filled with new product. The empty pallet on the denesting cell is indexed away from the lifting mechanism, and then transported to the stacking cell via a conveyor. A new full pallet enters, ready for denesting.  
 
The stacking end reverses the infeed process. The empty pallet from the denesting side is indexed into position, and the stacker starts. Each tray is pushed into the system from a conveyor, and the machine indexes down to be ready for the next tray. This will continue until 24 trays have been stacked onto the pallet. The full pallet is then indexed out of the stacking position, and a new empty pallet is then indexed into position. The process then repeats, ensuring maximum success and efficiency.