Here the machines achieve impressive accuracies. For example, they reliably mold – supported by a 3D image processing with two camera systems – single bond wires with an accuracy under 20 µm. These accuracies are achieved even in 3D mounting with microcomponents. Gerrit Häcker: "We have developed a modular system for the individual work steps such as gluing, dispensing and placement, which we combine individually. There are 35 different systems available for the assembly process."

Here the highest quality requirements apply. An ESP system in the vehicle, for example, obtains information from twelve or fourteen sensors that must operate with extremely high reliability: failures should not arise here. The machines that Häcker builds for this task produce around 15 million sensors per year with an error rate of well below 1 ppm (parts per million). At the same time, customers expect a very high availability of the machines that run three shifts continuously throughout the year – and they expect flexibility. Even small quantities can be manufactured economically and quickly, without the quality being affected. Gerrit Häcker: "Our machines need to produce the highest quality even with a small lot size and frequent process changeovers."

In complex machinery – the 18-axis machine for the passport production is a good example – such requirements can only be met if one collaborates with selected partners even for the supplied components such as the drives and uses absolutely high-quality components.

This also applies to the energy and data cables that are routed to the gripping, fitting and dispensing units via the x, y and z axis. Häcker pursued, inter alia, the development goal of being able to operate the machine for five years free of maintenance. Jens Beyer, technician in charge of cable assembly at Häcker Automation GmbH: "Our machines complete 5-7 million cycles per year in single shift operation, it can be up to 20 million in 24-hour operation." This means: all moving components including cables must be developed for the extreme application of 100 million motion cycles without maintenance or even replacement.

Häcker found a match for this demanding requirement profile in the igus® cable range, after using other cables that were prone to failure and did not meet the high standards. There is a reason why things are different with the igus® cables. The signal and energy cables of the chainflex® series were specifically designed for use in energy chains® and are characterised by extremely long life with constant stressing through the energy supply movements. New conductor materials as well as special jacket materials are used for them – with the result that the cables when used in energy chains® last many times longer than conventional cables. The dreaded "corkscrewing" followed by core breakage is already avoided by the basic structure of the chainflex® cables – a system that igus® discovered in 1989 and continuously developed since then.

Another design detail: the protective jacket – which the user can choose from seven different materials – is executed with "gusset filling". This means: the jacket envelops not just the cores (then the necessary support for the stranded cores would be missing), but the jacket material is also injected between the core stranding powdered with talc. This ensures that the core stranding does not open by the movement, but can be guided back and forth like in a channel.

These details show: in highly stressed energy chains®, cables that were particularly developed for this application should be used. Häcker uses, inter alia, chainflex® cables of the Series CF 2, CF 10, CF 11, CF 27 and CFPE as a protective conductor and views the selection as excellent, because actually no failures have occurred so far despite the high demands and the millions of movements.

Häcker poses high demands even on energy supply systems: they have to run with low friction and free of vibration at high and low speeds. The compactness also plays a role: the assembly operations are mostly done in a work area of 500 x 500 mm, and a precept of Häcker designers is not to "give away" any installation space for the energy chain®. The energy chains® are also partially integrated in the compact drive and function modules.

This is a demanding criterion for an energy chain® that moves at a speed of up to 5 m/s and an acceleration up to 40 m/s² with each motion sequence. Jens Beyer: "We also place high demands on the wear behaviour of the chain, since our machines are working mostly in a clean room." Under these conditions, the energy supply chains in the igus® E6 Series prove themselves, which Häcker uses for the linear guiding of the x, y and z axis. These chains are characterised by a very quiet, low-vibration operation – an essential prerequisite in microassembly. And they are extremely durable.

However, it is not just the chain itself which guarantees a long service life of the energy supply system. Detailed work is also always called for here, which igus® and Häcker completed together.