Motoman Robot Handling and Tray Packing PET Plastic Bottles

Summary

System achieves all project goals. Highly flexible system accommodates a wide variety of bottle shapes. Gripper uses common components that make this system very easy to program.

Project Challenges

• Robot will pick and place a row of PET bottles into a tray in 4.5-5.0 seconds, and pick and place an empty tray in 5.0 seconds. (Incoming bottles will be neck up and not shingled.) Full trays will transfer out of the pack cell in 5.0 seconds.
• System will handle a variety of tray sizes, which can be located in both orientations, and a variety of PET bottles including reverse-taper bottles. Bottle placement in the trays is neck up only.
• Maximize throughput by eliminating downtime, and reduce costs by improving productivity and flexibility.
• Improve quality and eliminate bottle marring/denting through robotic handling, and reduce need for manual labor.

Motoman Robotics Solution

Motoman Robotics provided a custom UP50 tray packing solution that serves two bottle lines, including:

• Motoman UP50 robot with XRC 2001 controller.
• (2) Bottle infeed conveyors: – Table-top chain conveyors for transporting product into the cell and presenting it for robotic pick-up – one 3.66-m (12') L and one 4.88-m (16') L, and a 90° curve to separate the two distinct bottle containers. – Bladder part escapements and end gates, and bladder stops to accumulate bottles in the queue zone. – Air-actuated bottle stop separation devices to handle reverse-taper bottles. – Photo eyes for part metering/sensing down bottle conditions.
• (2) Indexing empty tray conveyors – 106.68 cm (42") W, and 3.05 m (10') and 4.11 m (13' 6") L. Twin-strand indexing chain conveyor with tilting tray nest. Includes remote pushbutton station with on/off, E-stop, and manual/auto functions.
• (2) Bottle pack zone tray conveyors – lineshaft type, with 5.17-m (17') L, 1.07-m (42" ) W tray tilt mechanism; (2) air-actuated blade stops, and a 90° pusher.
• (2) Gravity outfeed conveyors – 1.07-m (42") W with 1-3/8" rollers on 3" centers with fixed end-stop.
• Allen-Bradley SLC 5/03 PLC package with HMI.
• Custom end-of-arm tooling – multi-function mechanical rail gripper with two zones and compliant rubber inserts for product handling and vacuum cups for tray handling.
• Cell guarding package, including: dual-channel safety hardware; three-color system status beacon with audible alarm; wire perimeter safety fence; two access gates with positive-break safety switches; and two conveyor pass-through openings protected by three-sided enclosures to limit operator’s reach into the cell.

Fixtures/Tooling Details

Motoman Robotics provided custom end-of-arm tooling, consisting of a mechanical rail gripper with compliant rubber inserts designed to handle one row of bottles at a time. Two zones accommodate various tray sizes and will handle them in either orientation. Vacuum cups pick up empty trays. Gripper uses off-the-shelf gripper bodies and does not need to be adjusted between bottle types.