Up to fifty servo axes in a small space, high dynamics, high demands on service life and small bend radii: Can one-cable technology function under these adverse conditions? IMA Klessmann did not just try it out, but thoroughly tested it together with the motion plastics specialist and cable manufacturer igus®. Result: The hybrid cables of the chainflex® product range are tried and tested and used in the new flexible IMAGIC flex drilling systems.
60 metres per minute: IMA Klessmann GmbH's wood processing machines are clocked at this speed. This applies to numerous processes in the fully automated flow production of residential, office, kitchen and bathroom furniture – for example for edge processing with sawing, chamfering and/or gluing.
However, this speed also dictates the material processing rate of the drilling stations that have been integrated into the machinery. They have to drill at high speed, even if the components are manufactured according to specific orders and have different drilling patterns.
The IMA Klessmann "Drilling Technology" business unit has developed the flexible IMAGIC flex drilling system precisely for this application profile. It offers the user real added value in production. The individually controllable drilling spindles enable horizontal and vertical drilling and dowelling and promise minimal set-up times even for complex drilling patterns – and at a remarkably high speed, as is shown in a demo video from IMA Klessmann.
The systems, which are always customer-specific, are equipped with up to 50 axes, which must be positioned and coordinated in seconds. In order to prepare the IMAGIC flex for this task, the designers had to "upgrade" the drive and control technology appropriately and decided to use the latest servo technology. This allows highly dynamic movements with high positional accuracy and extremely fast feedback.
One of the highlights of the new automation system is the innovative energy and signal supply system. The new one-cable technology combines the power and feedback system in the same servo cable. This greatly reduces the time and effort required for the material and commissioning, but initially it presented the responsible persons at IMA Klessmann with a real challenge. Burkhard Reese of the division of stationary and drilling technology electrical final assembly: "We needed a hybrid cable that ensured a long service life and operational reliability with the high dynamics." “
All stakeholders at IMA agreed that it was worth pursuing this goal, not just for technical reasons. Marcel Sulewski, team leader of electrical purchase: "Depending on the position of the switch cabinet – which is specified by the customer – we can fit up to four kilometres of cables. The one-cable technology thus saves the costs and the installation effort considerably. We just had to make sure it worked reliably. “
Doubts were certainly expressed here, since leading companies in control technology had given up the idea of a one-cable concept in the past – the risks seemed too great. IMA took these concerns seriously, especially since the mobility of the hybrid cables was added as an extra factor. And the first request to igus® didn't dispel the doubts. Burkhard Reese: "We gave the parameters to igus® under which the cables are used, and asked if the guaranteed service life was valid. The clear answer was "No". “
The reason for this was the small bend radii in which the cables were used in the servo axes at IMA. They are partially up to 50 percent smaller than that specified in the catalogue. igus® has extensively tested all the chainflex® hybrid cables (which are available according to the standards of more than 30 servo system manufacturers), achieving more than 25 million cycles per cable without failure, but these values apply to the standard conditions while complying with the defined bend radii.
Of course, igus® did not leave it at that, but offered IMA a tailor-made test programme. Andreas Muckes, chainflex® product manager: "We tested and examined the hybrid cables according to the specification of the drive manufacturer and the Hyperface DSL bus element with over 4 million strokes in the IMA-specific bend radii. Then we handed them over for the real test at IMA. " In the case of the bus elements in such a cable, practical testing is absolutely vital to compliment test measurements.
The combined tests in the igus® laboratory, which is the largest in the industry with a floor area of 2,750 square metres, and IMA's series application were so successful that nothing stood in the way of a serial production launch. Both companies benefited from the experience of this test series. And, ultimately, the end customer is also assured by a reliable statement, since he has safely tested a new technology from the very outset.
The hybrid cable range is available with both PUR and PVC jacket. What may be surprising is the fact that IMA chose the PVC option of the chainflex® hybrid cable. Andreas Muckes: "Particularly in high-speed applications, the majority of the machine builders use cables with PUR jackets as standard." IMA already had good experience with PVC in the past. Burkhard Reese: "We also use PVC jackets for other cables. They are abrasion-resistant and highly durable and fail-safe even in highly dynamic applications. Marcel Sulewski supports this decision from the purchasing standpoint: "In view of the large quantity of cables, the use of cables with PVC jacket also offers significant cost savings. “
On the cost side you can also take advantage of the plug-in system. The harnessing is also simplified, meaning IMA also makes use of the services offered by igus® and purchases ready-to-install "readychain®" systems with igus® energy chains. In doing so, open energy chains are used, which repel wood dust. This allows customers to rely on safe systems from a single source, where the components have been harmonised by the decade-long development programmes in the igus® test laboratory.