Maximizing Efficiency: A Multi-Robot Injection Molding Cell Produces a Complete Shaker Cup in One Cycle

Yushin America in Cranston, R.I. demonstrated the power of integrated robotics by building a sophisticated cell that combined two injection presses—each equipped with a servo‑driven linear robot—with a seven‑axis collaborative robot (cobot). The system is designed to showcase how diverse robotic functions can be leveraged to complete an entire product line‑haul within a single molding cycle.

The finished item is a polypropylene “shaker cup” used for milk‑shake and mixed‑beverage preparation. One press forms the cup body, while the second press creates a flip‑top lid with a living hinge. Both components feature threaded connections, allowing the robots to perform precise unscrewing operations using their servo wrists.

During demolding, the robot assigned to the cup not only extracts the part from the mold but also inserts an in‑mold label, then hands the cup to a pad printer for final identification. The second robot handles the lid: it unscrews the component, secures the pour spout, inserts informational cards, and re‑assembles the cup and lid by screwing them together. Finally, the cobot places the fully assembled product onto a conveyor for downstream processing.

By integrating demolding, labeling, printing, and assembly into one seamless workflow, Yushin America’s cell exemplifies how robotics can dramatically increase throughput, reduce manual intervention, and maintain high product quality—all while keeping the robots—and, metaphorically, the “job” busy.