An injection molding cell gives the robot two jobs in one cycle: take the finished part out of the mold, and deal with the runner and sprue that come with it. This application story covers an injection molding EOAT we built for large automotive parts, where the traditional heavy tooling was replaced with an organic printed structure, lightweight sprue grippers, and a quick connect system that changes over in seconds.
What Injection Molding EOAT Does
Molding end of arm tooling removes the part from the open mold, and in most cells it also grips the runner and sprue for degating, the removal of gate and runner material from the molded part. The tool has to be stiff enough to hold position between mold halves, light enough for the robot to move fast, and fast to change when the next mold goes in. Those three demands usually fight each other, which is exactly where printed tooling changes the math.
The Application: Large Automotive Parts
For this automotive application the frame is an organic printed structure engineered for maximum stiffness with minimum material, with the vacuum channels for the cups running inside the printed body. Part and runner are picked in the same cycle, and because the structure carries only the material the load paths require, the whole tool stays light enough to run on a smaller robot than the metal original demanded.
Key Features
- Organic structure engineered for maximum stiffness with minimum material
- Internal vacuum channels feeding the vacuum cups, printed into the body
- Lightweight custom grippers for runner and sprue handling
- Quick connect for fast EOAT swapping, with no adjustments needed after changeover
Rethinking the Sprue Gripper
Molding EOATs traditionally carry heavy, expensive mechanical grippers just to hold the runner and sprue. In this build we replaced them with a 3D printed gripper body driven by a lightweight cylinder, and in many cases we were able to connect more than one gripper to the same actuator, cutting both weight and pneumatic complexity. The animation below shows the printed pincer design in action.
Quick Connect, Quick Changeover
Mold changes are where molding cells lose hours, so the tool uses our proprietary quick connect system: the EOAT swaps in seconds and returns to position with no adjustments, improving the efficiency of the entire production line. It is the same changeover philosophy behind our Manual Tool Changers, built directly into the molding tool.
Why 3D Printing Wins in the Molding Cell
Every molded part is different, and printed tooling lets the EOAT geometry follow the part instead of approximating it with catalog components. Contoured nests, integrated air routing, and consolidated structures come at no cost premium on our SLS systems, and a tool revision for the next mold is a new print rather than a rebuild. See more molding work on our molding applications page, or browse the full range of robot end of arm tooling.
Molding EOAT Questions
What is degating in injection molding?
Degating is the removal of the gate, runner, and sprue material from a molded part after molding. Robotic degating combines part specific grippers with nippers or cutters on the end of arm tool.
What does injection molding EOAT pick?
It removes the finished part from the open mold and typically grips the runner and sprue in the same cycle, so the press can close and start the next shot sooner.
How fast can a molding EOAT be changed over?
With a quick connect system the tool swaps in seconds and needs no adjustments afterward, which keeps mold changes from turning into tooling projects.
Automating Your Molding Cell?
Tell us about your robot, your product, and your target cycle time, our team will recommend a tooling design that fits your payload, changeover, and budget.
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