LSR optical solutions shown at K 2019

Düsseldorf, Germany — There were two live optical molding demonstrations performed by injection molding machinery producers at K 2019 in Düsseldorf.

Tokyo-based Toshiba Machine Co. Ltd, which will be renamed Shibaura Machine Co. Ltd in April 2020, molded a complex automotive LED headlamp optical lens part.

The lens was designed in LSR by Wyoming, Mich.-based LumenFlow Corp., and Toshiba referred to it as a part "that cannot be replicated with more rigid materials." Lumenflow has more than 60 optical LSR molding machines running in its plants in the U.S., Mexico, Hungary and China.

The LSR used was Silastic MS-1002 Moldable Silicone from Horgen, Switzerland-based Dow Europe GmbH, molded on a 50-ton Toshiba ECSXII all-electric injection molding machine, supported by a Top 5000 P LSR mixing and dosing unit from Oftering, Austria-based Elmet Elastomere GmbH. Toshiba said integrated the hot runner control allows easy conversion from a LSR machine to a thermoplastic molding one.

An FAA-015S-15-8.8 takeout robot with dual function end-of-arm-tooling (EOAT) from Kyoto, Japan-based Yushin Precision Equipment Co. Ltd removed the parts from the mold, a universal base and two-cavity LSR mold in RoyAlloy stainless steel with a single-drop cold runner system, all supplied by Brea, Calif.-based M.R. Mold & Engineering Corp.

Yushin says the robot is "more agile, smarter, faster than previous models, with cycle time 10 percent faster than predecessors." Its features include active vibration, arc motion and adaptive motion control.

Schwaig, Germany-based Sumitomo (SHI) Demag Plastics Machinery GmbH ran another LSR optical molding demonstration. The company's all-electric drive IntElect 130-250 machine produced a matrix headlamp optical part with 14 integrated lenses for adaptive light control, using Dow Silastic MS-1002 Moldable Silicone in a four-cavity mold from "tailored" optical mold maker and molder Aachen, Germany-based Innolite GmbH.

Cycle time was 60 seconds, and the parts, each weighing 6.45 grams, were removed from the mold by a Demag SDR 5-25 S servo motor-driven three-axis linear robot, which also presented them for quality assurance inspection.

SHI Demag said the machine, which was equipped with a SHI Demag NC5plus control system, has "20 percent lower energy consumption than competitor systems." It added that enhancements such as a redesigned vacuum program and improved pump performance contribute toward "high processing stability needed for processing an optical grade silicone material," as does a new "LSR package" with a new shut off nozzle, the screw, barrel and nonreturn valve all designed for optimized processing of LSR, the company revealed.

Servomix Z200 mixing equipment from Eberstalzell, Austria-based Nexus Elastomer Systems GmbH fed LSR components to its DT-RE-M-E B base mixing head. Nexus also supplied the molded part weight inspection system involving two weighing scales and closed-loop regulation via the Nexus TimeShot balancing system, which adjusts the amount of LSR injected into the mold by varying injection time.

Nexus additionally provided the visual quality inspection system. It used In-Sight cameras from Brunn am Gebirge, Austria-based Reliste GmbH to detect air pockets and contamination. The results were analyzed, displayed and stored with use of Reliste's EasySightPro Max 7.1.3.0 optical inspection software.

As a mold maker, Todtnau-Geschwend, Germany-based Zahoransky AG had earlier molded a nonspecific two-component thermoplastic/LSR component on its Fakuma 2018 booth, illustrating the cooperation that had been recently set up with Freiberg am Neckar, Germany-based Edegs Formenbau GmbH to combine Edegs' experience in production of tool inserts and cold runner systems for LSR molding with Zahoransky's established mold making expertise.

Zahoransky has meanwhile been constructing and selling the resulting complete LSR mold systems under the "Z.Warp move" name. This could be seen again in a live molding demonstration on Zahoransky's K 2019 booth with a Z.Warp move mold, where the company produced magnifying "glasses" combining unreinforced PBT for the two body components and clear LSR for the two lenses.

The two two-component PBT/LSR parts, each containing a five-times magnification LSR lens, were assembled in the mold so that they can be rotated in use for the opening to be used on their own and closed together with the two lenses together then providing 10 times magnification.