Complex cell batch produces autonomous radar-capable vehicle transceivers

At Fakuma 2021, Sumitomo (SHI) Demag Plastics Machinery GmbH, Schwaig, Germany, will demonstrate the production of backlit IMD badges for use in autonomous driving systems. Comprising an all-electric injection moulding IntElect 220/660-1100 machine, specially equipped with a plasticising unit to process crystal-clear polycarbonate (PC), the pioneering production cell introduces the company’s first SAM-C linear robot developed in-house.

Designed to measure, detect and locate obstacles and enhance autonomous driver safety by interacting with the environment, the moulding specialist will showcase the fully automated production of automotive sensors designed for exterior vehicle applications. To achieve optimal resolution, the seamless IMD process involves back-injecting the radar sensors’ second surface using single-image decors before cleaning the emblem using contactless technology.

Henrik Langwald, Director of Automotive & Electronics Business Development, describes the process:  “After the part has been sprayed, the robot enters the mould extracting the finished part using a removal gripper which it places in a receptacle located on the servo motor sliding table. From there it is held in place within the laser station. The sprue is separated, free falling into a box. The cycle then continues towards the CO2 cleaning station, with the robot resuming its standard position. Every cleaned part is removed from the receptacle by the robot using a transfer gripper and placed visible side facing up on the conveyor belt, with the robot continuing the cycle returning to its component extraction position above the mould tool.”

Specialists in thin film technology and functional decorative coatings, LEONHARD KURZ Stiftung & Co. KG adapted the innovative IMD process which involves repositioning the IMD films to the movable platen during each cycle  using a classic roll-to-roll process with a film feed device. The SAM 10-C linear robot adapted to the fixed clamping plate is used for removal of the component. It then takes over the complete part handling, using suction cups to remove the part from the  injection moulding tool, before storing it on the servomotor sliding table and then smoothly transferring the component onto the conveyor belt.

As extremely high-quality and sensitive surfaces, to protect the components from contamination the  injection moulding cell is equipped with a movable laminar flow unit. Supplied by airflow experts PETEK Reinraumtechnik, the ISO class 7 cleanroom cell uses the German company’s innovative Flowbox technology to deliver targeted filtered air into the corresponding film feed unit and handle&place automation area, explains Langwald. He adds:  “UV curing is not a requirement for this specific application. However, for future flexibility, the exclusion strip can be switched out and the UV module inserted.”


IMD advantages


For high-tech automotive radar surfaces, IMD is an economically viable and more sustainable option, offering the capability, design freedom, repeatability  and energy efficient production.

"Indium-based metallisation is radar-compatible," the expert assures. “Using this technique means that the functions of corresponding sensors located around a vehicle are not disturbed. Such systems offer an important design advantage over conventional sensors because they can be concealed using optically non-transparent materials. This is due to the different wavelengths of the radar beams compared to visible light beams.”

Evaluated against lacquer or PVD processes, the IMD manufacturing process is significantly more economical, with the automotive expert reaffirming the benefits of having a continuous, uninterrupted  work flow for production and emblem decoration. "Additionally, this will be our first live demonstration of the contactless cleaning technology,” announces Langwald.

Other advantages of the process are design freedom, energy efficiency and sustainability. Through the integration and synergy of the IMD process with the moulding component production, no extra processing is required. This significantly reduces CO2 emissions. "Additionally, during the IMD process decorative layers are transferred as a dry coating system. This eliminates the likelihood of wet coating contamination. Furthermore, no  post-drying energy is consumed,” states Langwald.


Always supporting the sustainability agenda


Component recycling, fewer pollutants and lower energy consumption are among the other advantages of the process being showcased at Fakuma 2021. "The IMD decoration process diligently supports component recyclability," says Langwald. Both IMD components and sprues, including decorative layers, can easily be recycled. Additionally, as the thin-film metallisation takes place within the decor, there are no hazardous chrome-6 issues.

In adopting this process, Sumitomo (SHI) Demag is living and standing by its new “Act! Sustainably” slogan being unveiled at the trade fair, whereby only equipment and machinery that drive sustainable and positive environmental actions will be presented by the company.

The IntElect 220/660-1100 being used for the demonstration at the booth fits this criteria exactly. Dynamic, precise and energy-saving, it features the latest servo drives that deliver improved repeatability and shorter cycle times. As a result of the in-house developed drive motors, frequency inverters and the entire servo motor control, the IntElect series remains one of the most efficient injection moulding machines on the market, consuming up to 20 percent less energy compared to conventional all-electric injection moulding machines. Further advantages are higher availability and greater precision, both of which have a positive effect on the machine’s cost-effectiveness. "All relevant interfaces are integrated into the control system, as is the IMD package and standardised communication with our SAM-C robot," says Langwald.


Machine and robot from one source


Designed by Sumitomo (SHI) Demag to complement the injection moulding process perfectly, the biggest reveal at the trade fair is the company’s highly anticipated own-branded, SAM-C (Sumitomo Demag. Automation. Machine – Cartesian) handle&place robot series developed in-house.

“ For the IMD application, height optimisation is achieved using a compact telescope axis," explains Jürgen Schulze, Director Automation. Customers benefit from process and system technology from a single supplier source, complete with hardware and software control integration of robot technology into the injection moulding unit and production-optimised robotic mechanics fully customised to Sumitomo (SHI) Demag machines.

“With SAM-C, we have succeeded in engineering the smallest automated injection moulding cell, comprising robot and material handling technology," explains Schulze. “We offer high system availability with minimal repair and maintenance work, thanks to Sumitomo (SHI) Demag’s in-house servo motor technology and low-maintenance drive and guide technology. With the corresponding vacuum technology, the systems also deliver significant energy-savings."

Initially comprising four payload sizes - three, five, ten and 20 kg –the SAM platform will expand in phases over the next two years adding further robot kinematics and functional elements.

Other efficient automation concepts included within the IMD cell include  sprue separation and laser marking supplied by H + S Automatisierungstechnik GmbH, Groß-Umstadt; a cleaning station from Kurz subsidiary Baier GmbH + Co KG Maschinenfabrik, Rudersberg; the PETEK laminar Flowbox; and a CO2 laser system from Datalogic S.P.A., Lippo di Calderara di Reno (Italy) for sprue separation. Other partners involved in this innovative project include Universal Robots GmbH, Munich, supplying  the compressed air and a universal component cleaning cobot, and developer of the durable PMMA filter compound PLEXIGLAS® Röhm GmbH from Darmstadt.