Degating is one of the most monotonous and painful tasks when processing plastic molds: the human wrist isnot designed for the repetitive motion and strain of clipping of hard plastics. Thankfully, robots’ wrists are.
The wrist of a collaborative robot, like Sawyer from Rethink Robotics, is specifically designed for the repetition and precision of pick-and-place and part modification tasks. With a payload of 4 kg, seven degrees of freedom, an embedded vision Cognex camera in its wrist and 0.1 mm repeatability, Sawyer gave Harrison Manufacturing the chance to address its degating process.
“Cutting a gate over and over again, twice a minute for 10 hours a day is not healthy for your wrist,” said Scott Harrison, founder and president of Harrison Manufacturing, a custom plastics injection molding manufacturer, specializing in molded plastics and light assembly. “We’ve been seeking an automation solution for this task for some time, but traditional methods weren’t affordable or effective for our situation.As soon as we heard about Sawyer, we knew we’d found the answer.”
The small company injection molds products ranging from seatbelt parts to large air conditioner pads. To produce high quality products, Harrison could not afford to have its team members develop wrist-related injuries on the line over non-value-added tasks, so automation was a must.
“We have Sawyer set up to take parts from two different plastic machines,” Harrison explained. “It recognizes when the part is there, grabs them, and cuts the gate before turning around and placing it on a conveyor, where it eventually goes to a person who stacks it, straps it and packages it.”
Sawyer was able to take on more shifts than its human counterparts and improved part consistency and quality in the degating process by eliminating the chance for human error and injury. Harrison’s employees were also free to take on higher value tasks.
Sawyer’s small footprint was also ideal, as Harrison does not have the floor space to accommodate the large safety caging units that most traditional robots require.
Harrison was able to get Sawyer up and running from box to line in just a few hours.
Harrison will soon be implementing a second Sawyer robot.“A year from now, we’ll probably have another Sawyer unit downstream that will accept the parts at the other end of that conveyor and stack and strap it,” he said.
The Harrison team is also considering deploying Sawyer in a variety of other tasks, including part inspection, quality assurance, pick and place, and line loading and unloading.
Jim Lawton, COO of Rethink Robotics explains how collaborative robots like Sawyer are making an impacton the way manufacturers of every size are improving production quality and worker safety.
“From reduced worker strain to increased throughput and part consistency, manufacturers that leverage adaptable, smart robots are improving their manufacturing processes in a significant way,” said Lawton. “Repetitive, ergonomically challenging tasks are prime for automation, and Harrison Manufacturing is a great example of how Sawyer can drive value in several ways.”
For more information about Sawyer, visit the Rethink Robotics website.