OEM&Lieferant Ausgabe 1/2019

116 Manufacturing Intelligent automation of a machining centre Process-reliable solution for multiple variants By Ralf Högel, Freelancer Today, the automation of machine tools with robots is standard, but with a diverse range of parts it can quickly become a challenge. An experienced system integrator can offer optimum solutions for difficult cases – as evidenced by the path-breaking automation of the machining centre of a leading electronics manufacturer. Wieland Electric GmbH is a medium-sized family business with headquarters in Bamberg and is among the pioneers in electrical con- nectivity solutions. In the course of its more than 100 years of existence, the company has grown into an international group with a global workforce of more than 2,200 on all five continents. Today it is seen as a medium-sized global player with a clear commitment to its location in Germany, where the majority of products are still manufactured. The Franconian city of Bamberg is where robust housings for the well-known series of revos industrial connectors are made. A Müga S500 machining centre now drills holes and cuts threads in the upper and lower sections of the housing. In bygone days, the machine tools were loaded and unloaded manually. This very aspect had been a thorn in the side of Frank Hennemann, production planner at Wieland, for some time: “Employees who were urgently needed for other, higher-level tasks were engaged with simple, monotonous activities. Besides that, manual loading was less than optimal for reasons of productivity. In order to remedy this situationwe contacted EGS Automatisierungstechnik. We knew that the company had acknowledged expertise in the automation of machine tools.” Indeed, EGS has already implemented hun- dreds of automation solutions for machine tools and can draw on a wealth of experience. Nevertheless, the assignment at Wieland proved to be a real challenge, as EGS Sales Manager Heiko Röhrig quickly realised: “The concept was complicated by two factors: firstly, the large number of housing versions, and secondly the processing of bulk material to bulk material. In other words, the housing components are delivered in a disorderly man- ner in metal bins and leave the system again as bulk material.” Highly flexible feed system offers the solution Although the parts were supplied in a disor- ganised form on workpiece carriers or pallets, a suitable feed system was identified in the standard EGS program. With a few modifica- tions it was seen to represent the optimum solution: the SUMO Flexiplex. In this highly flexible loading system, the workpieces are transported on multi-lane belts. Major advantage for this solution: all versions of the connector housing have a common characteristic: their width is always between 42.5 and 43.5 millimetres. The lane width of the Flexiplex does not need to be adjusted in the case of retooling, which is why the infeed at Wieland dispenses completely with this adjustment option. With the different parts lengths, which depending on the version vary between 60 and 140 millimetres, and the housings heights, which range from 24 to 90 millimetres, the EGS feeding solution has absolutely no problem with the many special housing shapes, some of which have a stain- less steel bracket or locking pins. Only a clamp arm had to be additionally installed. In contrast to the infeed, deciding on the right robot was easy. Röhrig: “Although the cus- tomer had not expressed a preference when it came to the robot manufacturer, the choice was made in favour of YASKAWA – with good reason. Due to their robust design, MOTOMAN six-axis robots are especially well suited to the tough conditions on and in machine tools. Furthermore, they are characterised by an impressive degree of precision, excellent dy- namism and a good price-performance ratio.” In this particular case, EGS opted for the MOTOMAN MH12 for all handling tasks within the cell protected by a wire cage. The correct positioning of a total of eight lanes of the Flexiplex with blank parts remains the task of the system operator, as is the placement of empty metal bins for collecting machined parts. The bins are brought to the cell workspace on a driven roller conveyor, and when filled they are discharged onto a Images: © Ralf Högel System overview: left the eight-lane infeed; right the empty metal bins for the finished parts; in the background robot and machine tool.