The production cell with robot handles both pallets, raw parts and workpieces and tools.
The Toman company wanted to add a 5-axis machining center to an existing automation system and invested in the Versa 825 machining center from Fehlmann. Only the companies Fehlmann and P-Cam were willing to take on this task.
To expand capacities, take another step towards Industry 4.0, and become even more competitive, the automation solution with robots was to be expanded a year later to include a 5-axis machining center. Two 3-axis machines have been used to manufacture within an automated cell at the Toman company in Wolfratshausen, Bavaria, since 2018. With one of the two 3-axis machines, a Picomax 95 from Fehlmann, in which the company invested in 2018, people in Wolfratshausen had had excellent experiences, so it was decided that the new 5-axis machining center should also be from Fehlmann.
Complex workpiece handling and variable clamping pressure
The problem with this project, however, was less the machine. Instead, handling parts and workpieces with batch sizes between 1 and 10,000 pieces/year is very complex, and the structural conditions need to be improved. That’sThat’s why managing director Josef Toman was looking for suppliers who would support this project with individual and compatible products. On the other hand, he also expected people to be willing to find solutions with the appropriate flexibility and know-how: “We looked at the Versa 825 at Fehlmann, which is a proven machine that runs stable, reliable, and precise. We are milling on it for 18 to 20 hours a day, and I’m sure it will remain stable for years. That’sThat’s what we were looking for because a failure within the automation would be catastrophic. As far as automation is concerned, our system configuration is not commonplace. For example, the management and software connections through PCam are brilliant. However, the companies Fehlmann, PCam, and Schunk have shown themselves to be very open, flexible, and at the same time competent.»
These requirements begin with the production cell with the robot, which handles pallets, raw parts, and tools. In the area of workpieces, this solution offers two options. After a gripper change, pallets or a clamping system from Schunk can be exchanged. On the one hand, raw parts can be fixed via the pneumatically controlled clamping system. On the other hand, it is also possible to turn the workpiece and initiate complete processing. Interestingly, the clamping pressure can be variably adjusted via an M function (the control for the clamping system was developed by Fehlmann).
Flexibility A prerequisite for cooperation
Toman’sToman’s wishes and requirements were indeed very individual. So the robot should also exchange tools from the production cell via the spindle. A plan that, except for Fehlmann and PCam, met with no understanding from any other provider. However, as a parts manufacturer, you have to be flexible. At least, that’s how production manager Herbert Schmidbauer sees it. For him, flexibility and competence were the basic requirements for working together: “We don’tdon’t know today what will come next year. We must also plan for the future. In connection with the tool change via the spindle or the handling of raw parts and pallets, we have often heard from competitors that you don’tdon’t need that after all. I don’t know if these companies couldn’t or didn’tdidn’t want to. But these statements were an absolute knockout criterion for us. One example is the variable clamping force because I need a different clamping pressure for roughing than for finishing or filigree components. Only Fehlmann and Schunk have dealt with this topic and developed it accordingly. This also applies to the tool change via the spindle or the integration of the somewhat older 3-axis machine.» Storing the tools within the cell has the advantage that the tool changer in the machine does not have to be oversized, and one can also store overlong tools.
The investment by the manufacturer of the parts in Wolfratshausen is a consistent, future-oriented concept. Particularly the Versa 825 reliably and efficiently maintains tight tolerances of less than 1/100 mm. However, Wolfratshausen is already busy again with new planning for the future. The intention is to integrate a paternoster rack to equip the entire cell with workpieces and tools in the hope that this project will bring back the necessary flexibility
The original article in German on maschinenmarkt.ch