Case History: Lid Molding System Improves Cycle Time, Saves Floor Space

Responding to a booming North American market for wet wipes, Husky Injection Molding Systems has developed a unique approach to molding hinged, flip-top lids for wet wipes containers. Husky has found that the new approach can lead to a 10 to 15% increase in output, with an accompanying 15 to 25% reduction in floor space, when compared to conventional systems.

Most flip-top lids are injection molded and free-dropped, or removed by a robot. The lids are then closed outside the press area with a closing machine. While these methods generally work, free-dropping could damage or cause potential part jams, while using robots increases overall cycle time, floor space and costs.

SwingChutes, a patented in-mold product handling system, gets around these limitations by the use of a cam or servo motor-driven shaft, which rotates and positions a part removal arm in front of an ejecting part at mold open. Vacuum suction cups on the end of the removal arm securely grasp the ejected part. As the mold closes, the lid is folded and the part is positioned in a guide chute mounted on the side of the mold. A pneumatic cylinder snaps the lid closed before the part exits the mold area. From the guide chute, parts can be easily conveyed to other downstream processes.

“By snapping the part shut while the press is closing, we can greatly improve the reliability and cycle time of the system,” says Bruce Catoen, Husky vice president of Automated Systems. “We were able to reduce the cycle time for one customer using a 2 x 8 flip-top system by more than 20%.

The New England Consulting Group estimates that the wet wipes market in the U.S. is worth US$2 billion, with projected sales of US$4.5 billion by 2010. SwingChutes can be incorporated in a wide range of other applications, including closures, containers and housings.

Husky Injection Molding Systems Inc. 905-951-5050