An automated cell phone housing assembly line was designed by Spectra Technologies Inc. (Euless, TX) for EIMO Americas (Vicksburg, MI).
The assembly line consists of 12 stations that combine to automatically load, assemble, process and unload parts. Ten of the 12 stations use SpectraFlex modular process platforms equipped with Staubli Corp.'s (Duncan, SC) RX60 six-axis robots and CS7B controllers. An asynchronous conveyor transfers pallets between stations. The major stations include: loading and unloading parts to and from a tray, picking and placing gaskets or protective covers for the cell phone housing, and two gluing operations.
A SpectraFlex tray handler at three stations presents parts to the robot. The robot picks the parts from the tray and places them onto the working pallet. The end effector is single or double tooled, depending on the application. The tray handler automatically cycles full trays into the workstation and stacks them. An operator periodically loads full trays into the handler and removes the stack of empty trays.
Three workstations pick parts from a tape and reel feeder and use vision guidance for accurate placement onto the cell phone housing. The robot acquires the part from the tape and presents the part to a vision camera. A second camera captures the location of the subassembly as the working pallet transfers into the station. The part is then placed onto the subassembly.
Adhesive operations are also performed at two workstations to join parts of the subassembly. The adhesive dispensing valve is located on the end effector. The adhesive is dispensed as the robot traces the required paths.
Another workstation places a protective cover onto a lens and housing subassembly. A tape and reel feeder presents the protective cover to the robot. The robot picks the cover and places it on the lens and housing subassembly.
An unload station uses a tray handler to supply empty trays to the robot. The robot picks the completed assembly from the pallet and places it into pockets in the tray. When full, the tray indexes out and is stacked. Another empty tray is indexed into the station.
Each modular process platform is identical except for custom tooling, process devices and process-specific programming. The stations can be easily reconfigured for new processes. Each platform features a SpectraFlex modular I/O panel, and a standard bolt pattern is supplied on the tabletop worksurface and the upper mounting surface.
The I/O panel connects to the system enclosure using plug-and-play cabling. Each panel provides 32 local inputs and 32 local outputs via Eurofast connectors. Multiple I/O panels can be mounted in various locations in the platform to provide flexibility.
The robots are mounted to the upper mounting plate in the platform, providing an open worksurface. The controller is mounted in the base of the machine, along with the control enclosure for easy access.
Each platform is located next to the conveyor. A lift-and-locate unit is attached to the platform to lift the pallet from the conveyor and locate it for assembly. This lift-and-locate unit allows the workstation to run off-line is desired.
A 15-inch touchscreen with Win 2000 and Adept Windows provides an operator interface for each workcell. A SMEMA interface connects each workcell. Each workstation is connected via an Ethernet cable to a supervisory station where the line data is collected, displayed and stored.
Since implementing the six-axis robots, the company has saved floor space. Along with moving the secondary operation to the press side, throughput has increased and staff level has been maintained. The company has also more than doubled its sales.
"Whether injection mold press tending or assembly, we have had zero downtime after installation for robot-related problems. Most of our arms have more than 2 million cycles on them," says Preston Patnoude, an advanced manufacturing engineering leader at EIMO Americas.
For more information on robots, call 864-433-1980 or visit www.staublirobotics.com.
For more information on automation systems, call 800-779-5678 or visit www.spectratechnologies.com.