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Patent Report: Process extrudes multiple layers

Issue: March 2017

Guill Tool & Engineering Co. Inc., West Warwick, R.I., has invented a method and apparatus for creating high-strength extruded products by forming multiple laminated flow streams. It’s a one-step annular system that could create an almost unlimited number of layers of plastics. The newest patent application, which adds rotary motion to the technology, builds on a portfolio of Guill patents in the field dating back several years.

“The big picture of this technology is being able to create these tens to thousands of layers in tubes which can enhance a variety of properties beyond just strength, depending on the plastics and layer sizes,” said Robert Peters, manager of R&D at Guill.

According to the patent application, laminations are amplified by repeatedly compressing, dividing and overlapping them. A tubular microlayer product is created from the combined laminate output, which could be used to produce tubing or blow molded products.

The system’s extrusion die assembly has passages set around a central axis that are offset from each other by approximately 60 degrees. A rotating die eliminates knit lines.

Doug Smock

“While sheet microlayer technology has existed for decades and many of the benefits have been explored, the adoption of this technology has been primarily limited to the sheet and film industry,” Peters said. “We are hoping to bring and to expand upon this technology to the world of tubular extrusion with processes that are simpler and products which are superior to those currently available.”

Patent Application 20170001393; published Jan. 5

Nordson’s new PolyStream valve assembly provides closed-loop control  in extrusion coating and laminating applications.

Extrusion coating. Nordson Extrusion Dies Industries LLC, Chippewa Falls, Wis., has commercialized a motorized back-pressure valve assembly for extrusion coating and laminating that provides closed-loop control. “The PolyStream valve assembly is the first completely hands-free system for regulating back pressure in extrusion coating,” said Sam G. Iuliano, business development manager for polymer dies. “Back-pressure conditions are affected by numerous factors and are in a constant state of flux. By making operator intervention unnecessary, our new system helps to ensure coat weight consistency, adequate adhesion to the substrate and a high level of product quality.”

The purpose of the back-pressure valve is to accommodate the high melt temperatures needed for extrusion coating, temperatures that are higher than those used in other extrusion processes. However, because excess back pressure can lead to polymer degradation, the new EDI PolyStream motorized valve assembly can be placed between the extruder and the die. In the invention’s closed-loop concept, the valve’s drive responds to a controller that receives signals from a pressure transducer. The valve opens based on back-pressure readings. The valve assembly includes a motor, breaker plate screen pack, linear valve, melt pipe, control system and optional display panel.

Patent filing number: 14/814,071. Application not yet published.

Faster purging. In an effort to save operator time and reduce resin waste, Fanuc Corp., Yamanashi, Japan, has invented a system to automatically detect when a purging cycle in an injection molding machine has been completed. In the invention, a sensor detects the color of a purged resin and relays that information via Bluetooth to an analysis unit. When a purged material is cleared, the molding cycle with the new material begins.

Patent Application 20160361855; published Dec. 15, 2016

Patents and patent applications can be viewed at www.uspto.gov

Have you applied for or received a
patent? Contact dsmock@plasticsmachinerymagazine.com