Conveyors Synchronize Arrival

Integration within a packaging line can be complicated. So, too, can integration between a firm's packaging and other operations.

DePuy ACE (Warsaw, IN), a Johnson & Johnson company that manufactures implants and other orthopedic devices, needed to ensure that each product was paired with its correct paperwork at the beginning of the packaging process. On top of that, it needed to figure out a way to get the implants from a noncleanroom environment to the cleanroom where the packaging takes place, without interchanging the airflow between the two areas, which would compromise the cleanroom pressure standards.

The firm was able to meet both needs with a customized conveyor system from Shuttleworth (Huntington, IN).

The device is conveyed down one line and fed into an automatic transfer machine, which peforms the final cleaning and passivation. Then product is discharged into the cleanroom. On a separate conveyor, totes carrying documentation of each implant's manufacturing history are brought into the cleanroom and matched before packaging. The two conveyors are synchronized with a programmable logic controller to ensure that the correct product and documents arrive at the same time. Once the match is made, the empty baskets and totes are transported back to the starting position via a lower deck conveyor.

"Our main objective in automating product handling was to reduce the risk of human error by simultaneously moving product and paperwork into the cleanroom automatically," says Steve Harges, a senior manufacturing engineer at DePuy. "As the project developed, we recognized the additional benefits of automating the return of the empty totes and product baskets. Labor has decreased. Organization and efficiency have increased. This frees [employees] to do other tasks."

To address the cleanroom airflow issue, Shuttleworth designed an interlocking pass-through box to ensure proper air pressure in the cleanroom. When product arrives, the cleanroom operator opens the outer door. Once product is removed and the outer door is closed, a sensor automatically triggers an inner door to open for the product and documents to enter. But the access doors to the cleanroom remain closed, preventing air escape.

"We had some problems to overcome, but Shuttleworth was able to custom design an interlock," Harges says. "It wasn't an off-the-shelf item." The system as a whole, he says, has "been performing really well. We're really pleased with it."