Just as zone defense is used in basketball as a means to defend specific zones of the court and ultimately protect the goal, zone defense in conveyors also works to protect a goal — but this time the goal is a product or package.
Accumulation zones can pose a potential threat to packages on a conveyor, particularly lightweight containers without much packaging protection, notes Bryan Boyce, product manager of conveyor products for Intelligrated, Mason, Ohio. “They’ll bounce like a basketball when you run them into each other,” he says. In using zone control, a programmable logic controller (PLC) can automatically reduce the speed of the conveyors as they go into accumulation mode so that the cases will match up to each other without impact and damage, he says.