Emerald Group Publishing Limited
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Robots help improve production at Delphi
Robots help improve production at Delphi
Keywords: Plastics, Robots, Production
Delphi Automotive Systems recently added 16 injection mold machines to its Vandalia, Ohio Interior Systems production facility. This system represents the plant's first experience using articulated robots over traditional three-axis gantry style robots for injection mold machine unload operations.
In order to improve productivity and position Delphi's Vandalia operations to handle future business, a production team determined that a fully automated part removal system would help the plant meet its production goals and maintain a competitive edge. Because of the large open work envelope of the system, the team considered using three-axis gantry robots to unload the injection mold machines. However, after evaluating the flexibility provided by articulated arm robots for secondary operations, the team changed its mind.
In addition to providing more flexibility, Delphi required the repeatability that articulated robots could provide when compared to gantry devices. Repeatability was a critical factor considering the large production orders that Delphi had received to produce door panels, inserts and modules for a wide range of vehicle platforms.
A third factor in the decision to go with articulated robots was the plant's need to accommodate low ceiling height clearances – an issue that could not be satisfied by a gantry supplier.
The system incorporates 11, Fanuc M-16iT overhead, rail-mounted robots working on 1,500 ton injection molding machines and five Fanuc S-420 pedestal robots working on 3,000 ton machines (Plate 4).
Articulation is the key characteristic of the M-16iT. Compared to traditional linear gantries which typically use only linear rails to perform robot motion, the M-16iT use rotary axes or articulated “joints” for load/unload and post-processing motions and a linear axis for repositioning, allowing it to make flexible, human-like moves.
Plate 4 Gantry Robot unloads 1,500 ton injection molding machine
A second benefit of the M-16iT, which differentiates it from other industry standard gantry robots, is its six-axis arm design, allowing six degrees of robot operation. The six axes of freedom allow the robot to perform tasks that were typically reserved for a human operator. Because the robot comes standard with six axes, most operations, from part rotation to intricate part placement and assembly, can be handled without expensive options or fixturing. In addition, the robot's simplified installation alignment greatly reduces installation costs compared to standard gantries.
A third benefit of the rail-mounted solution is that end-of-arm-tooling is simplified, and in some cases can be shared between part runs. This means that the robot arm is flexible enough to extract parts from either the top or side of the machine.
The six-axis, S-420 robot offers an extremely long reach and a heavy payload capacity of up to 175 kg (386 pounds). The flexible S-420 also features a large work envelope and a 360° wrist rotation, making it easy to maneuver larger parts.
Here's how the system works
Delphi uses 11, M-16iT robots mounted on top of 1,500 ton injection molding machines to unload automotive interior door panels and map pockets. The M-16iT's compact size and flexibility coupled with a small overhead ceiling height requirement makes the robot ideal for this application.
For most of the operations, the M-16iTs perform the work of typical gantry extractors. As the injection mold machines open, the M-16iTs enter the mold cavity areas, extract the parts and place them onto a takeaway conveyor. For some operations, the simple extraction is coupled with value-added operations such as part de-gate or heat treating. When one of the additional tasks is required, the robot positions each part in front of a stationary heat gun or material removal tool. The robot's ability to articulate the part allows for consistent positioning for the secondary operations.
Since the 3,000 ton machines do not allow enough ceiling clearance for a top-mounted robot, Delphi uses the S-420 robots to extract large inner door panels as well as interior and exterior trim pieces. The S-420s, which are installed beside each machine, easily change from one job to another with no production interruptions.
All of the robots operate using FANUC Robotics' HandlingTool application software. HandlingTool simplifies and standardizes robot setup and operation. Because little or no programming knowledge is required, HandlingTool is easy to learn and use.
FANUC Robotics had full turnkey responsibility for the system which currently operates 24 h per day, 5 days a week.
Delphi's production team noticed improvements to the system almost immediately after the robots were in operation. First, the robots perform part extraction at much faster speeds than gantry robots.
According to Ben Turzynski, manufacturing engineering supervisor for the Vandalia plant, the typical gantry solution requires 13 s to fully remove a part from a 1,500 ton injection mold machine. The FANUC Robotics solution requires only 5.5 s to remove the same part from a 1,500 ton machine.
“We're extremely pleased with the increased speeds provided by the articulated robots,” added Turzynski.
Another key advantage of the articulated robotic solution is accuracy. “The FANUC robots pick parts from the molds and successfully handle them over 99 per cent of the time,” said Turzynski. “Gantry style robots successfully pick parts only about 90 per cent of the time and are more likely to drop parts,” he added.
For Delphi, the FANUC robots' repeatability and accuracy allow for consistent part extraction, which has led to consistent mold cycles and higher quality parts.
Not only has yield and quality increased, but the robots provide Delphi with maximum flexibility that will enable the plant to easily handle future automation applications.
Multinational Delphi Automotive Systems, with headquarters in Troy, MI, USA, Paris, Tokyo and Sao Paulo, Brazil, is a world leader in transportation and mobile electronics components and systems technology. Delphi's three business sectors – Dynamics and Propulsion; Safety, Thermal and Electrical Architecture; and Electronics and Mobile Communication – provide comprehensive product solutions to complex customer needs. Delphi has approximately 213,000 employees and operates 176 wholly owned manufacturing sites, 41 joint ventures, 53 customer centers and sales offices and 30 technical centers in 38 countries. Delphi can be found on the Internet at www.delphiauto.com
For more information visit the Web site: www.fanucrobotics.com