The production line is fed by a case erector that is able to run at 30 boxes/minute. However, the warehouse staff on the assembly line can only manufacture the boxes at 15 boxes/minute. This bottleneck limits the overall manufacturing throughput of the factory and results in the case erector being used at only 50% capacity.
The case erector folds and drops boxes onto a low conveyor belt, which then feeds an elevating conveyor to raise the boxes to standing height. Afterward, the boxes are moved to a 24-foot long filling conveyor where warehouse staff place products into the boxes before they are closed and palatalized.
Develop a system that pushes every other box onto a takeaway conveyor to feed a secondary filling conveyor. This split should occur between the elevating and filling conveyors to avoid unnecessary lifting. Additionally, the boxes need to be turned 180° between primary and secondary filling conveyors to facilitate easy staff movement and material replenishment. The system should also allow modes to operate either conveyor independently while setting up new production runs on the other side or if the demand doesn’t require both lines.
The Raspberry Pi Pico runs a custom Python program to manage the I/O and act as the brain of the system. A proximity sensor is mounted on the conveyor belt, detecting boxes as they pass by. For every other signal received from the sensor, the Pico activates a relay switch connected to a 24V solenoid. When this solenoid is energized, it pushes compressed air into a pneumatic cylinder, extending its piston to push the box onto the takeaway conveyor. The rail on this conveyor is positioned behind the leading edge of the box, causing it to rotate 90° when pushed. The box then moves down the belt until it is pulled onto second filling conveyor. A rail attached to this conveyor catches the same (now trailing) edge of the box to turn 90° more so the boxes on the first and second parallel filling conveyors are facing each other.
The cost of the box pushing system, excluding the conveyors, under $40. Including the takeaway conveyor belt and the 24-foot secondary filling conveyor, the total project cost to double production capacity was less than 10% of the initial capital expenditure on the box former. Additionally, this design only increased the footprint of the original production line by 15%.
This project doubled the production capacity of the factory, crucial for meeting Q4 demand. Beyond seasonal demands, because of its low cost and small footprint, the system could remain in place during off-peak periods, and staffed when needed. These efficiencies and scalability allowed for a reduction in labor hours with flexible staffing during off-seasons while year-over-year sales continued to increase.