Interior grab handles are injection-molded parts. They cannot be dropped from the mold because the surfaces are soft and easily damaged. The eight core pieces must also be automatically loaded into the injection mold at each cycle. There must be zero missing pieces.
Ten minutes of forced convection cooling, prior to the pieces being manually handled, is required. Additional in-mold cooling time is not an option, because increased cycle time reduces production output and increases cost. The pieces must be cool enough to allow for required manual assembly prior to packaging for shipment.
The system occupies minimal floor space between injection molding machines and has high reliability. It provides trouble-free operation 24 hours a day, 7 days a week without impeding the molding machine.
The first step of the solution was completed by TRW. It installed a robot to automatically unload the molded handles and maintain orientation control. The second step, completed by Clear Automated Structures, was to provide a conveyor to move and cool the many parts. A twin track XT Q-module conveyor was chosen. The pallet fits the application perfectly, allowing the four molded handles to be placed and transported. The 15-foot-long by 4-foot-wide closed loop conveyor track provides enough linear footage to allow the finished pieces to cool before final assembly and packaging.
The conveyor has four operating positions with provisions for a fifth station to handle automated packout, using standard FlexLink pallet stops and locate stations. These positions include a manual load and unload station; part presence verification; a robotic pick-and-place station; and cooling tunnel with a 10-pallet capacity.
Fifteen pallets with custom fixturing are used to provide the queue at each operation. A heavy-duty drive handles the accumulation created by the numerous pallets, each carrying 10 pounds.
The XC structural system with polycarbonate panels encloses the back end of the conveyor. Cabinet fans force room temperature air over the parts for cooling. A PLC provides the control logic to interface the robot with the conveyor and operator, as well as the inspection station.
The integration of the project was a complete success due to the efforts of the individuals from TRW and Clear Automated Structures.
The system has the ability to operate unattended for several minutes, while the operator is performing packaging tasks. "We accomplished a 26 percent increase in production with the installation of this new line," says Keith Orrell, manufacturing engineering manager.
For more information on conveyor systems, call Clear Automated Structures at 860-621-2955 or visit www.clearstructures.com.
