A custom hinged mount for de-stacking system provides enhanced pivoting alignment
Automation is a continually evolving way to improve efficiency, especially on the production-line. While system integration can incur high start-up costs, manufacturing lines running 24/7 save thousands in annual labor costs. This was the case for a newly designed bottle cleanser packaging and sorting conveyor using PBC Linear actuating systems in a de-stacker. However, during the early stages of testing, the actuators were found to be loaded beyond their rating, and damaged when the system misaligned by out of position product pallets. This resulted in machine shutdowns and potential safety concerns.
The de-stacker is positioned at the forefront of the robotic packaging conveyor. Stacks of boxes on pallets containing empty bottles are stocked in the front, waiting to be moved further down the packaging line. As the de-stacker cycles down the pallet stack, it moves the 272 lbs pallets into position to be lowered onto the conveyor and on to the next station. This mechanism required a complete system of durable and sophisticated actuators to work synchronously to complete the de- stacking tasks.
The PBC Linear solution
To meet the challenge, the design team decided to implement PBC Linear’s versatile MT series actuators into the robotic conveyor and de-palletizer. Installed into the system, the MT linear actuators were used to complete two different tasks: horizontally driving the bottle boxes into lowering position and vertically raising/lowering the boxes onto the transfer conveyor. These tasks needed optimal control, smooth linear motion and tolerance for high offset loads. Initially, the design team was pleased with the performance; however, they soon began to notice significant strain on the vertically mounted actuators; eventually causing the line to be shutdown. In order to find a solution, PBC Linear was asked to provide specific application assistance with the problem.
The MT series had several key advantages that made it an attractive positioning system for this application: high load tolerances facilitated by a steel-reinforced timing belt, smooth motion and velocity control supported by a ball guided rail system, and t-slots to mount vertically and horizontally. When PBC Linear investigated the actuator breakage, they realized extreme moment loads were the root cause. The load ratings of the actuators were barely exceeded during normal operation; however when the boxes were misaligned, the actuators were exposed to more than twice their rated load capacity. This excessive offset load directly lead to machine shutdown and repair, and required an immediate solution for the manufacturer to keep their lines operating.
To absorb the high moment loads, PBC Linear installed new actuators (same model and size) with dual carriages to absorb higher moments. They also designed and manufactured a special hinged mount to attach the de-palletizer to the actuators in order to prevent breakage and machine shutdown. The two mounting plates were spring-loaded, allowing for the actuators to pivot when the boxes were misaligned. This prevented the actuators from being strained under high moment loads.
Results / ROI
After the actuators were equipped with the new customized mounting plate, the production line has been operating smoothly. Overall, the manufacturer was pleased with the design team’s packaging system and PBC Linear’s expert actuator support.