Injection molding cell combines high article variance with automated product changeover.

With the turnkey solution, 159 product variants can be manufactured.

16:9

Flexible Production Concept Combines High Article Variance with Automation

Automatisierungszellen

Automatisierungstechnik

Spritzgießen

Kunststoffverarbeitung: Verfahren

Mehrkomponenten-Spritzgießen

Automatisierungskomponenten

Spritzgießwerkzeuge

Kunststoffverarbeitung: Maschinen und Komponenten

Werkzeuge für die Kunststoffverarbeitung

Inserttechnik

Linearroboter für die Kunststoffverarbeitung

Handling, Handhabungstechnik

Multiaxialroboter für die Kunststoffverarbeitung

One System, 159 Variants

Automotive supplier Coko produces four structural parts and twelve visible parts for a truck driver’s cab on a fully automated injection molding line.

Dominick Sudeck (left), Global Process Management, and Sascha Böning, Industrial Engineering, in front of the production cell’s complex handling system.

Coko Manufactures Different Automotive Parts on a Single Turnkey System

Montagetechnik

Industrieroboter

Industrieroboter klein

Montageeinrichtungen

KFZ-Zulieferer

Dienstleistungen

Sixteen in One Go

Touch-sensitive films, which previously only worked on flat surfaces, are now also available in three-dimensional for curved components. This offers completely new product and design possibilities. In order to maintain functionality, expertise and the right touch are required. This is exemplified by the company Hoefer & Sohn, Fürth, Germany, which produces 3D touch panels for washing machines and dryers on turnkey systems from Arburg. 

Automated Injection Molding of 3D Touch Panels at Hoefer & Sohn 

Folientechnik (IMD, IML, FIM, u.a.)

Kapazitive Sensoren

The Right Touch Required 

Anyone looking around Fakuma could discover automation solutions to suit any budget and applications of any complexity. The forerunners of Industry 4.0 were also to be seen. 

Fakuma 2017 Offered a Wide Range of Solutions for Flexible Automated Production 

Industrie 4.0

Hybrid-Spritzgießen (Metall / Kunststoff)

Handhabungsroboter

From Versatile to Highly Efficient 

Zahoransky supplies systems and injection molds for manufacturing breakage-proof primary packaging for pharmaceuticals. Three typical applications.

The double quick-change system for pipette tips permits rapid restart of production after brief maintenance interruptions.

Medizintechnik

Medizinprodukte

Pharmaceutical Primary Packaging  with No Risk of Breakage

The announcements in the field of injection molding give the impression that the developments of recent years are continuing. These include the increasing digitalization of injection molding production, as well as highly integrated production cells that combine very different competencies. The spotlight shines not only on the machinery, but rather on optimum system solutions for integrating molds and individually configured peripheries in the digital and the real world. 

Fakuma 2018: Injection Molding Networked and Integrated 

Steuerungen (Hardware und Software)

ERP-Systeme

Treibmittel

Spritzgießmaschinen

Spritzprägen

Elastomer-Spritzgießen

Schaumspritzgießen

Temperiertechnik

Reinraumsysteme / -technik

The Communicative Machine 

Making a racket is part of the trade. In the past, tradesmen would do this at markets by swinging wooden rattles to attract attention. Today, instead, it is the industry which is trying to make its developments heard and accepted, for example at trade fairs and in the media. What has injection molding technology had to offer recently, aside from Industry 4.0? The answer is process developments that in the main expand the range of applications for plastic parts, mechanical assistance systems that enable consistently high part quality to be achieved more reliably, and the huge field of temperature control. 

New Ways to Attain Special Part Properties Are Advancing the Art of Injection Molding 

Steuern, Regeln

Verbundwerkstoffe / Werkstoffverbunde

Qualitätssicherung

Making a Racket for Plastics  

Flexibilization of production, lightweight design, functional surfaces, increasing product customization, consistently low reject rates etc. ¿ the OEM wish list is becoming longer and longer. While the OEMs are the main drivers in the injection molding segment, their mounting demands are challenging Tier 1 suppliers, mold makers and systems suppliers alike. For an interview, we met with specialists from GKTool and HRSflow, for whom the search for new solutions is daily routine. The topic is integration ¿ of ideas, processes and system partners. 

Christian Götze (GKTool) and Moreno Carvani (HRSflow) about Cost-Efficient Production through Integrated Mold Technology 

Normalien und Heißkanaltechnik

"With System Integration,  Fewer Errors Occur" 

In a joint project, seven companies developed a combination of technologies for manufacturing electronically functionalized high-quality surfaces, e. g., for applications in and on the car. Demo parts were shown in public for the first time at Fakuma 2018.  

Combination of Technologies for Manufacturing Electronically Functionalized Plastic Parts 

HMI, Bedienelemente, Displays

Polyurethan

Oberflächentechnik

Laserstrukturieren

Lackieren

Premium Surfaces by the  One-Shot Process 

Over past months, many in-house workflows and development processes have slowed down and also changed. Nevertheless, time has not stood still, also not in injection molding technology. The debate and development have been shaped by two themes: digitalization and the circular economy. Below are some examples of developments and projects that underpin this trend.

Two displays are seamlessly integrated into the continuously 3D-formed instrument panel

Innovative Injection Molding in Times of Pandemic

Künstliche Intelligenz für die Qualitätssicherung

Industrie 4.0 für die Qualitätssicherung

Software

Digitale Transformation

Wirtschaft

Innovationen und neue Technologie

Biokunststoffe

Kunststoff Werkstoffe

Spritzgieß-Sonderverfahren

Nachhaltigkeit

Umweltmanagement

Spritzgießsimulation

Simulation

Schnecken und Plastifiziersysteme

Industrie 4.0 für die Kunststoffverarbeitung

Machine Learning / Künstliche Intelligenz für die spanende Fertigung

Industrie 4.0 für die spanende Fertigung

Kunststoff-Recycling

Kunststoff-Aufbereitung

Lasermarkieren

Laserbearbeitungen

Inline- / Online-Messsysteme

Qualitätssicherung Kunststoff

Kreislaufwirtschaft

There Is More beyond the Horizon

The Kunststoff-Institut Lüdenscheid is currently focusing its development work on combining glass and plastics in an injection molding process. It is forming functional assemblies of flat and shaped glass with plastic. In the last step, researchers are attempting to injection mold the plastic melt between a glass pane and capacitive film, with the aim of generating a functional touchpad in one shot. 

The Plastic-Glass Composite is Reaching Completion with the Integration of  Capacitive Sensors 

Glas

Backmolding Formed Glass 

Today’s printed electronics on injection molded parts always have a multi-layer structure. Decor films are back-molded using the FIM process, and the electronic functions are applied via an additional rear backing film. Now, new materials permit the integration of both layers on a three-dimensional shaped film with decor and imprinted circuits. This enables off-tool functional decor components to be produced by the subsequent injection molding process. 

Heyco Produces Injection Molded Parts with Class A Surface and Integral Electronics 

Bedrucken

Decor and Function on One Film 

In one of the cavities, a control display is created in so-called dead-front design with a touch sensor. In the adjacent cavity, a component is made with faux-concrete surface aesthetics that can be lit from behind. At the Fakuma trade show, KraussMaffei and Leonhard Kurz demonstrate the degree of functional integration made possible by combining the IMD and IML film processes. The new IMD SI Duo film feed is the first-ever solution capable of positioning two decorative strips independently of each other. The first series application is already up and running. 

KraussMaffei and Leonhard Kurz Optimize the Combined IMD and IML Film Processes 

Three at One Blow 

The company Leonhard Kurz is a specialist in the development and production of decorative and functional coatings for plastics applications, which are applied by means of carrier foils during injection molding. Essential objectives of the company are technology and process development as well as the optimization of the 3D foil forming around corners and the contours of the plastic parts. For this purpose, Kurz operates an extensive injection molding technology center. New in the machinery: two production cells based on servo-hydraulic injection molding machines from Wittmann Battenfeld.

Decorative and functional coatings, such as those developed and produced at Leonhard Kurz in Nuremberg/Fürth, Germany, enable efficient implementation of new design concepts, shown here, for example on a car door panel with variable and dimmable backlighting

Leonhard Kurz Has Extended its Development Capacities with Injection Molding Systems from Wittmann Battenfeld.

Spritzgießmaschinen, allgemein

Messtechnik

Sensoren / Messwertaufnehmer

From the Roll to the Third Dimension

Analysing and verifying, milling and dispersing, pump and systems

Netzsch Gerätebau GmbH Thermische Analyse 

https://www.netzsch-thermal-analysis.com

Analysegeräte

Werkstoffprüfung

Analysewaagen

Mechanische Messtechnik

Ausgabegeräte

Bedienterminals

Computer Hardware

Auswerte- und Analysesoftware

Betriebsausrüstung / Betriebsmittel

Betriebstechnik für Kunststoffverarbeitung (Peripherie)

Dimensionelle Messgrößen

Kalibrierdienste

Identifikationssysteme und Komponenten

Optische Mess- und Prüftechnik

Inline-Messtechnik

Laborgeräte

Laboröfen

Messung von Umgebung (Klima)

Lasermesstechnik

Lasersensoren

Messdatenerfassung und -verarbeitung

Messdatenerfassung, Software

Messgeräte

Messzubehör

Messgeräte für Automobiltechnik

Messgeräte, sonstige elektrisch

Elektrische / Magnetische Messtechnik

Messmittel

Messsysteme

Messtechniksoftware

Messung von Gasen und Flüssigkeit

Messverstärker

Probenvorbereitung

Schwingungs- / Vibrationsprüfger

Sensoren,  optische

Thermoanalyse

Werkstoffprüfung, mechanisch

Zerstörungsfreie Werkstoffprüfung

Control panels in which the functional and decorative layer is subsequently applied to the part by hot-embossing or bonding are imported in large quantities from Asia. In Switzerland, the IWK, together with some industrial partners, recently completed a project that shortens the production of such parts to one injection molding process, and thereby also makes them attractive for processors in Western Europe.

The production of functional control panels in a one-step injection molding process also makes production attractive for processors in Western Europe.

Smartphones and many other devices from the field of entertainment electronics are now operated as a matter of course by touching a capacitive surface. Now, this technology is continuing its successful track record in the fields of household appliances and automotive interiors. It offers some important advantages. On one hand, ever more functions can be integrated into a control panel without increasing the complexity of the modules. On the contrary, a large number of keys, toggle switches, rotary knobs and roller wheels are replaced by a single part, which is also characterized by an attractive design. On the other hand, this technology allows a high degree of standardization to be combined with the introduction of new business models – an important trend in the automotive industry. Specifically, the vehicle manufacturer only enables the individual functions that are concealed behind the semi-transparent printed film on the part surface when the customer books them.

But the OEM benefits not only at the revenue side, but also at the cost side. Since several individual parts, such as the aforementioned switches, are no longer required, for which injection molds, often designed in two-component technology, had to be produced, one is now sufficient. Another advantage is that the OEM avoids the production of several similar module types with different functionalities – together with the underlying supply logistics – since all functions are already integrated in one part without additional effort.

To establish this technology in the industrial location of Switzerland, the Institute of Materials Technology  and Plastics Processing (IWK) in Rapperswil, together with four industrial partners, investigated the basic conditions for implementation in series production. The IWK is based in the canton of St. Gallen on the eastern shore of Lake Zurich, and, according to the director of the institute, Prof. Dr. Frank Ehrig, it is one of the biggest institutes in the department of engineering at the Eastern Switzerland University of Applied Sciences (OST). In this case, the project partners mainly include the injection molding processor A. & J. Stöckli AG and the Kurz Group, manufacturers of decorative and functional layers applied to backing films, and two end customers, who have their products manufactured at Stöckli, but do not want to be mentioned by name. At the suggestion of the IWK, the hot runner manufacturer Günther is also on board.

The project was co-funded by Innosuisse, the Swiss Innovation Agency. Ehrig, co-founder of the IWK 2005, explains the background: “The technology itself is not new, it dates back to the surface specialist Kurz, and has already been in use in some applications for a long time. The products we are talking about are now largely from Asia. There, however, the films are subsequently laminated, both the decorative film and the functionalized surface.” Of course, such labor-intensive processes are not possible in a high-wage country. “The aim of the project was therefore not only to investigate what such equipment could look like in the future if this technology were used, but also how it can be manufactured fully automatically,” continues Ehrig.

Injection Molding, Decoration and Functional Integration in One Step

To illustrate how, in the production of such control panels, the operating, design and functional surfaces are merged together in one shot, Curdin Wick (Fig. 1), head of the department of injection molding/PUR at the IWK, projects a video of the process onto the wall of the conference room during an on-site meeting. In principle, this is a combination of the IMD and IML processes on the two opposite sides of the mold.

On the moving side of the mold (Fig. 2), the part is decorated with a decorative surface by the IMD (in-mold decoration) process, in which a multilayer lacquer package with a customer-specific design is transferred to the plastic part during the injection molding process. After each cycle, the film (manufacturer: Kurz) is fed by a film feeder positioned on the machine platen, as though from a photographic film roll, while the consumed backing film is wound up below the clamping unit. The individual image film automatically stops at the correct position and is fixed on the cavity with a clamp frame. Then the air between the carrier film and the cavity is evacuated.

At the same time, a linear robot inserts a cut-to-size sensor film at the fixed mold side, which is also held in position by vacuum. This film, manufactured by PolyIC, a subsidiary of Kurz, is printed with a conductive microstructure and is backmolded by IML (in-mold labeling). “When the mold closes, the plastic is injected laterally into the 2 mm wide gap between the two films via a film gate,” explains Wick. In this way, a functional part is produced in one step.

In several project phases, the Swiss plastics specialists investigated both the process design and the design possibilities for the panel and the compatibility of different material combinations. For this purpose, a mold was first built for manufacturing a simple, almost flat test panel. Curdin Wick summarizes, “We tested various decorative film structures and several transparent materials, such as polycarbonate, PMMA or the copolyester Tritan, also as regards their scratch resistance. Depending on which material is chosen, the decorative film then has to be cured with UV radiation. The injection temperature also plays a role in how neatly the decorative film is transferred to the material, since there are already process-dependent restrictions. We then evaluated which material combination was most suitable.” The result was the films that are back-molded with PMMA.

With the trial mold, Wick’s team has also developed a processing trick: Usually, the so-called “tail” on the IML film protrudes – a process with which the part is subsequently electrically connected – in the injection molding process, at the side through the mold parting line. With the modified mold insert, the tail can be concealed in the cavity. “As a result, we can now place the tail in the center, because it can no longer be back-molded – it is usually at the edge,” says Wick, stressing another advantage.

In the next step, the IWK, with its project partners, developed a panel for a demonstrator (Title figure) from scratch. Now it was a matter of implementing curved surfaces (Fig. 3). “What degrees of forming will the decorative film still conform to? What design ideas and film sizes are possible at all? We wanted to ascertain that, also to take into account the various requirements of our project partners,” explains Wick. This was based on empirical values that Kurz has collected over many years. “We have gone close to the limits of what is feasible, but have not exhausted them, because otherwise we run the risk that wrinkling at the corners will prevent the paint from transferring neatly or even that the entire film will be warped, then the pattern will no longer be correct,” says the project manager.

However, only the decorative film (IMD) is applied to the 3D-formed part; in the case of the sensor film, it remains at 2D (or 2.5D in one direction). The fact that the sensor film lies flat in the mold can be recognized by a fine line on the finished part – this is the vacuum gap in the mold, which becomes visible on the surface of the film.

According to Wick, another project was to integrate so-called disappearance or dead-front effects, into the control panel. The panel appears as unobtrusive as possible when switched off, usually as a smooth black surface. After switching on, a control panel or translucent decorative film appears as a result of backlighting. This change between opaque, seamless design fronts and illuminated functional fields or decorative films can only be generated with a special layer structure, which Kurz prints on the surface of the IMD film in multiple steps.

As a technical basis for capacitive sensor keys, the film manufacturer PolyIC transfers a super-fine metal mesh, a type of silver-containing ink, to a thin (approx. 75 μm), flexible PET substrate, sometimes as a mesh structure, sometimes in the form of a diamond pattern or, as in this case, a backgammon pattern. This allows control elements in various sizes to be generated on both flat and curved surfaces. In terms of their intricate structure, the films are surprisingly robust. The injection phase takes place without special consideration, since, according to Wick, the electronics are on the reverse side, not on the injection side. “The plastic melt thus only comes into contact with the PET carrier film, not with the conductor paths.”

Nevertheless, it was important for the IWK to nominate a particular hot runner manufacturer for the project. The department head says, “The hot runner systems and nozzles from Günther have already worked very reliably in past projects. The mature technology pays off especially when, as in this application, high optical requirements, low shear loading with variable gate cross-sections and high process reliability are required.” He also highlights the clear-cut opening behavior, the uniform gate quality and the possibility of sequential injection. “The cooperation with Günther goes back a long way and also includes some extras. For example, a project is currently underway in which we manufacture two-component foams. Here, Günther has developed a new coaxial nozzle for us, with which we can process the two components by sandwich molding,” continues Wick.

For the control panel project, a standard 12NHT2 – 300S needle-valve nozzle (Fig. 4) was sufficient. The system nozzle with conventional heating element is screwed to the manifold. In the LA melt-chamber model (powder-metallurgical steel valve guide), it permits insertion as far as the article, and is therefore contour-determining. The valve guide can be easily exchanged if needed. By exchanging the valve guide and the valve, the diameter of the gate point can be enlarged or reduced without secondary finishing of the mold cavity. In a special design with a titanium ring as thermal insulation, the user can extend the application range of the nozzle to high-performance polymers, such as PBT, PEEK or liquid-crystalline polymers (LCP).

The BlueFlow thick-film technology from Günther is also worth considering according to Curdin Wick. “We also use nozzles with BlueFlow technology. Particularly in times of energy crisis, this technology is certainly an interesting option for processors. In our research projects, this is usually not so important, since other criteria, such as process reliability and product quality, are crucial.”

The injection-molded panel can be installed in an instant. After the film sprue has been cut off by laser trimming or milling, the tail, in its function as a simple standard connection, is clipped into the electronics of a circuit board. The control panel is thus ready for assembly. “In a real part, you would have only integrated snappers or screw bosses,” says Wick. As an example of a panel of the size of the demonstrator, he mentioned a coffee machine. Here, too, designers now would like flat, uninterrupted surfaces that are deactivated when switched off.

The sensor field of the film can be almost freely programmed. Depending on whether a keystroke or the movement of a slider should be executed by touch, the control system evaluates the proximity and position of the fingers. The switching operation is de facto triggered by a capacitance change. The advantage is that different product variants can be realized in one shot. After a film exchange (design change), for example, it is simply necessary to upload different software.

To demonstrate to interested parties and potential customers what design ideas can be almost playfully implemented in this way, Curdin Wick and his team have installed the new control panel as a functional “oven demonstrator” (Fig. 5). The controller for reading out the sensor film and for actuating the functions was completely developed by the Institute of Communication Systems (ICOM) of OST. If you hold the “naked” panel up to the light, you can already see the control panels shimmering through. But it is only when it is backlit after being installed that the various keys, sliders and symbols are visible in their full beauty. The icons disappear again when it is switched off.

The project ran for a total of two and a half years, and Stöckli, the processor based in Netstal of Glarnerland, Switzerland, put the system for the combined IMD/IML application into mass production during this period (Fig. 6).

Preliminary summary by Professor Frank Ehrig: “We have achieved our project goals and demonstrated that, thanks to the backmolding of functionalized films, large-area 3D-shaped panels with touch control can be produced economically. Although implementation is only worthwhile if the quantities are large enough, demand will increase. Only meeting optical and tactile requirements will no longer be enough in future. With increasing digitalization, panels must become the human machine interface in many areas.”

Günther Heisskanaltechnik GmbH  

https://www.guenther-heisskanal.de

Ausgabenartikel

So-called disappearance or dead-front effects are integrated into the control panel.

Fig. 1. Curdin Wick is department head for injection molding/PUR at the IWK and a lecturer in machine technology.

Fig. 2. Above and below the mold, one can see the equipment for tracking the IMD film (left), the six-axis robot in the background is inserting the IML sensor film (right).

Fig. 3. The aim of the second project phase was to implement attractive design ideas with surfaces that are as curved as possible.

Fig. 4. Günther, as the preferred hot runner partner, contributed the 12NHT2 needle-valve nozzle (in this case in the LA version).

Fig. 5. Demonstrator for the control panel of an oven with different  function keys and a slider for temperature adjustment: Each page on the  display can be designed in a different way. 