PRESS RELEASE
PRESS RELEASE - HEKUMA GmbH
7.5 Seconds per Part - 2 Million Units a Year
Press ContactKlaus Wanner / HEKUMA GmbH
Head of Sales & Marketing / Freisinger Str. 3B
Phone: +49 8165 633 -300 / 85386 Eching, Germany
eMail: / www.hekuma.com
Eching – February 2015
BERICHT_GearCover_02-2015 1 of 7
PRESS RELEASE
BERICHT_GearCover_02-2015 1 of 7
7.5 Seconds per Part - 2 Million Units a Year
Uncompromising with regard to high quality and reliability, a passion for detail and in solving highly complex tasks - this is what characterizes the collaboration between the Söhner Group and Hekuma. These qualities are demonstrated impressively in the development of the production concept and the design of gear covers for front windshield wiper systems.
A comparison of each company's quality standards, industry reach, planning expertise and production competence alone makes a collaboration between the Söhner Group and the high-performance system manufacturer virtually predestined. Söhner, a family-owned business located in Schwaigern in the Baden Württemberg area of Germany, has been symbolic for the last half century for the production of high-quality plastic parts - primarily for the automotive industry, but also for the sectors involving household technology, plumbing, electrical and medical technology. For more than 40 years, Hekuma has been developing high-performance automation systems for these industries in particular, which are designed to produce and inspect the parts and components needed for these sectors. The companies have been collaborating in the automotive industry for close to 14 years. The partnership is a good example of the high demands placed on plastic components that are relevant to safety and illustrates one thing: just how important it is to work as a seasoned team even beyond company boundaries.
One excellent example is the system that Hekuma planned, designed and put into operation at Söhner during the course of 2014. It is designed to produce gear covers for front windshield wiper systems. The covers consist of three components - 30% glass fiber reinforced PBT, as well as a white and blue-colored TPE seal. The parts, which are about the size of the palm of your hand, along with the combined sealing and electronic functions, are a clear example of how wide the communication and coordination basis is that the two companies operate on, not to mention the extent of precision applied by both companies. This allows a final result to be reached that meets each and every specification and parameter.
The most essential processing steps involve inserting six contacts each into four cavities of the mold (two fork-type contacts and two pairs of pin contacts each). In a subsequent process, an additional contact must then be hot melted. The responsibilities were clearly distributed from the start. "Söhner supplies the injection mold machine and the mold, Hekuma produces everything around it“ is how Ralf Kümmerle, Project Manager at Söhner, neatly sums up the cooperation between the two companies.
The 4+4 cavity injection mold was produced by Söhner for a horizontal injection molding machine. The processes: Contact insertion, assembly and inspection were already broken down into eight, fully automatic processing steps during the planning stage. The goal to complete the four parts within a cycle time of thirty seconds had already been established in the development plan. What was clear for Ralf Kümmerle from the start was that "this specification can only be achieved if each processing step is synced exactly to one another“.
The system's actual take-out and insertion process is completed over four cycles: After they are punched, bent and separated, the contacts are inserted into the tool and then over molded with the hard plastic component. The hard component is then conveyed to a transfer or turning station, swung upright by 180° and taken back up again by the gripper. In the next step, the hard component is inserted again and the TPE seals are injected on. In a final step, the hard component is taken out and passed along. Each insertion and take-out step performed by the independently moving gripper elements runs parallel to one another. While the finished part is taken out in the top part, the contacts are inserted at the same time in the bottom part of the mold - and all of this takes place in an area that is not even 1.20m² in size.
Subsequently, the gripper places the finished parts onto a shuttle, from where they are conveyed to the assembly and inspection automation area. There, the cover's mass contact that cannot be molded, is attached and hot melted.
In a highly complex process, the control unit links insertion and take-out processes to one another. The four gripper elements developed by Hekuma, each of which moves separately, require such an enormous range of positioning precision and an extremely high degree of reliability and speed that, as Kümmerle states, "at most only two to three companies on our hemisphere have the capabilities to meet a requirements profile of this kind." The most critical factor here is the maximum amount of competency that can only be obtained after years, or more likely after decades of experience."
The covers run through four different checks in the final quality inspection. First, the contacts undergo electrical testing, i.e. a continuity, short-circuit and high-voltage test. Then, the contact height is measured with a sensor, the surrounding seal is tested for leak tightness with air flow and the swash circumference of the pin tip is checked via camera.
The pin inspection is designed for a deviation of two tenths of a millimeter. To rule out bad parts as a result of measurement deviations altogether, the actual tolerance is set at around 0.018 millimeters, so around ten percent less. The final step of the process consists of assembling the pressure equalization membranes. The membranes are supplied from a reel with paper liner, stamped and inserted into the finished part by a pick & place system, welded in the laser welding station and subsequently tested with regard to the required flow rate before they are loaded into the tray.
After planning and engineering the system to the exact detail, approval testing of each processing step and how they were presented in the entire process brought the expected results. When it comes to the need to fine-tune the automation or making any adjustments to the individual processing steps, this is where the quality of the coordination efforts can be seen. Thanks to the intensive collaboration between Söhner and Hekuma that began well in advance, system completion, approval and its installation in China took just a mere eight months. "Working with Söhner is always such a pleasure. The coordination efforts run so smoothly and large projects of this kind can be managed within a relatively short amount of time" says Thomas Rüter, who has been providing sales support to Söhner for the last 12 years.
Kümmerle: "Crucial here was to ensure that the system remained productive throughout the entire process and uninterrupted to the extent possible. Injection molding processes must run constantly, because the material could degenerate if not. Cycle times during the inspection instances, for example, must never be allowed to exceed the total time allowed for the take-out and insertion process, including molding. The cycle time of 30 seconds was marked as the upper limit, so only 7.5 seconds remained for the four inspections sequences that each followed one after the next. Because the comprehensive leak tightness test per piece alone takes ten seconds, what we had to do was to expand the testing unit to two parts per cycle. This was the only way we were able to guarantee a production speed for four parts per 30 seconds throughout the entire process”.
The Söhner project manager was also extremely satisfied with the scrap rate and the system availability. "Here, too, Hekuma was able to satisfy all of the specifications' requirements. The scrap rate was below the maximum limit of 0.5 percent that we had stipulated. In addition, as concerns the overall availability, the system was always able to adhere to the limit value of 85 percent defined in the specifications. Given the system's technical complexity and the large number of processing steps integrated here, this is an excellent value!"
"This definitely guarantees our ability to produce two million parts a year", says Kümmerle: "With this system performance, we are definitely at the very top in the market, yet another factor that contributes highly to our ability to ensure our competitive advantage in the industry."
Together with three other systems that Hekuma developed for the production of gear covers for front windshield wiper systems, the Söhner Group was able to increase the total output to eight million gear covers a year.
As Kümmerle pointed out - the high quality of the Hekuma after sales service definitely plays a role in ensuring that these high output numbers can continue to run long-term. "After collaborating with Hekuma for almost 14 years, we know that their systems are extremely robust. Another advantage is the direct line of communication between our two companies. If there is ever a system malfunction, the Hekuma Service Team arrives on site quickly, or else, thanks to the transparent technology, we are able to fix any potential malfunctions entirely on our own”.
Membrane feeding and cutting station /
Membrane feeding and cutting station
Leak tightness or flow test of the surrounding TPE seal /
Leak tightness or flow test of the surrounding TPE seal
Electrical test /
4+ 4 cavity take-out and insertion gripper
Ground contact casting /
Pin height check
About Söhner
www.soehnergroup.com
The Söhner Group, an innovative family owned business, operates on an international level with locations in Germany, Great Britain, the United States and China.
The company was found in 1966 in Schwaigern as a toolmaking company and today employs a staff of more than 1,200 people worldwide.
Its experience gained over decades in R&D, production and automation flows primarily into products sold to the automotive supplier industry. In addition, the company provides services to customers in the fields of communication technology, plumbing and household technology as well as in the packaging industry.
The company not only manufactures injection molding and punching tools, but also highly complex plastic-metal products in reel-to-reel technology and as free-falling parts.
As a system partner, the Söhner Group provides support services to its customers through every phase of product development.
The Söhner Group had around € 165 million in sales in 2013.
About HEKUMA:
www.hekuma.com
HEKUMA (Eching, Germany) is part of the elexis Group. We create a sustainable competitive advantage with our innovative ideas and exciting technology in high-performance automation for customers in the plastics industry. With our dedication and ambition, we have established ourselves as a competent systems manufacturer and proudly look back on more than 40 years of experience.
We offer complex grippers for high-performance insert and take-out systems for injection molding processes with upstream and downstream automation. In addition, we consider our capability to develop turnkey solutions and production concepts, such as Sigma inside and HEKUflex to be one of our core competencies. We focus on the medical and automotive technology markets as well as the consumer goods industry.
BERICHT_GearCover_02-2015 7 of 7