#Product Trends
Precision that keeps pace
Pematech relies on linear technology from IEF-Werner
For automated testing and assembly processes to run economically and safely, the interplay between the system concept and linear technology is crucial. Special-purpose machine manufacturer Pematech has relied on components from IEF-Werner for years. Experience from numerous projects shows that precise linear technology, combined with in-depth expertise, contributes significantly to short cycle times and low production costs.
“We design and manufacture complete assembly lines for our customers as required, for example for printed circuit boards, electronic assemblies and devices,” Thomas Ketterer, Key Account Manager at Pematech, explains. The specialist machine manufacturer from Radolfzell at the Lake Constance, with around 80 employees, is part of the Swiss company Asic Robotics AG. Pematech’s portfolio includes automated test lines for a wide range of quality assurance tests, linear transfer and rotary indexing systems, robot cells, customised assembly solutions, and modular software programmes for control, process optimisation and product traceability. Renowned companies worldwide rely on the company’s in-depth expertise in the planning, design, manufacture and assembly of turnkey testing and assembly lines, as well as customised testing technology. Ketterer: “We tailor the systems precisely to our customers’ individual processes. This enables them to meet the often demanding requirements in terms of functionality, performance, efficiency and quality.” Customers are primarily based in Europe, Asia, the USA and Mexico. Pematech also supports users with a comprehensive service.
Every tenth of a second counts
“Many of our customers are in the automotive sector, which is an important but, above all, highly competitive market,” Ketterer says. In addition, there are medical technology, smart home solutions, consumer and industrial goods, and the electrical industry. These are often cycle-critical processes where every tenth of a second counts. This is particularly the case with automotive customers, for instance when assembling electrical sub-assemblies and components such as printed circuit boards. “The processes at the end-users’ sites must be perfectly synchronised,” Ketterer reports. “There must be no delays between the individual steps.” That is why linear technology plays a crucial role in handling. For years, the special-purpose machine manufacturer from Radolfzell has relied, among others, on its partner IEF-Werner from Furtwangen.
“Screwing, dispensing, cleaning, laser marking, resistance welding, end-of-line testing and plasma treatment – for an automotive customer, for example, we designed an assembly line that covers all process steps,” he explains. Additionally, there is the fully automated joining of a flexible printed circuit board with a plug connection, as well as external processes such as the application of thermal paste. The system operates using camera-assisted positioning with position correction and tolerance compensation. It is particularly suitable for three-dimensional, space-saving electronic assemblies. Furthermore, the line is connected to a higher-level Manufacturing Execution System (MES), with a line management system – the Pematech Line Manager – centrally consolidating data from all stations and serving as an interface to the MES.
This enables production and status data to be recorded in real time, creating transparency and ensuring end-to-end traceability. As an integrator and general contractor, Pematech has brought the individual processes together to form a coherent whole. The result: a tailor-made, reliable and fast line.
Challenge: 360-degree inspection
“We have supplied everything from individual axes for screw connections right through to gantry systems,” Thomas Hettich, who is responsible for Pematech, explains. He is the product line manager for linear axes and motorised rotary tables at IEF-Werner. “In total, there are just under 45 linear axes in the entire line.” As an example, Hettich cites a specific task in the designed assembly line: “The products must be removed from the workpiece carrier and inspected from multiple angles using camera systems. There must be no interruption to the process.” A maximum of two and a half seconds was available for this operation to ensure the cycle time at the end of the line was correct.
Together with Pematech, the IEF team developed a positioning system specifically for this workstation. It is based on IEF standard toothed belt axes from the Module series. The Module 68 z-axis was supplemented with an additional rotary unit. In total, this axis must move a mass of seven kilograms. The compact Module 68 linear unit is particularly suitable for use as a vertical axis and impresses with high repeatability of ±0.04 millimetres at speeds of up to two metres per second. “This combination of precision, dynamics and durability makes this linear unit the ideal solution for automated testing and assembly processes,” Thomas Hettich says. “Thanks to the modular design of the axes and the precise engineering, we were able to tailor the movements exactly to the cycle time.”
The Module 68 has proven itself time and again in practice: not only can cycle times be reliably maintained, but costs remain low, and adaptations to specific process requirements are easily achievable. “The kinematics allow the motor to remain stationary while the carriage is fixed on the Y-axis and only the base unit moves up and down,” IEF expert Hettich explains. “We can make optimum use of the space and ensure unobstructed travel paths.”
Right from the quotation stage, IEF-Werner provided CAD data and detailed designs. This meant that both parties could be confident that the system would be ready for use as planned, without any unexpected changes or cost overruns. Ketterer: “We can integrate the finished CAD drawing directly, and the delivery is arranged so that the axis arrives on the pallet ready for installation. This makes our work considerably easier and gives us a great deal of peace of mind.”
Reusable assemblies
A key objective in the development of special-purpose machinery is the ability to reuse individual assemblies. This means Pematech does not have to design every system from scratch. “If, for example, we use a gantry system, we can simply adapt, shorten or extend it for new projects without having to reinvent the wheel,” Ketterer explains. This approach simplifies the design, saves development time and enables machines to be built more efficiently and cost-effectively.
Close partnership for stable production processes
Pematech is impressed by the collaboration with IEF-Werner due to its in-depth technical expertise, practical advice and precise alignment with the systems’ cycle times. In one specific case, variants with two handling units were initially under consideration. This solution would have been technically feasible, but economically unattractive. Consequently, the decision was made in favour of a clever solution comprising a single unit, optimised by IEF-Werner in terms of both design and control technology, which offers the same benefits – whilst making the system more cost-effective and thus more competitive.
The robust linear systems operate with virtually no maintenance and ensure high availability. This is fundamentally important, but even more so for international customers, as a service technician is often not immediately available abroad.
“What I particularly appreciate about IEF-Werner is not just the quality of the axes, but the whole package – from design to practical implementation,” Thomas Ketterer explains. “For every system, we receive valuable guidance on cable routing or axis configuration and can optimally plan handling, force and speed. Critical factors such as electrostatic charge in the vicinity of sensitive products are also taken into account jointly. This saves time, reduces the number of handling units required and gives us a clear cost advantage. This is crucial for international competitiveness.”
