Automatic bending of sheet metal

The sheets to be bent are brought to the robotic cell on a europallet transported by a forklift, moved into the robotic cell and positioned by two magnets arranged perpendicularly to each other. The KR 150 L110 uses its suction cup gripper to pick up one sheet at a time, placing it in a centering station which measures the thickness of the metal sheet. The controller thus monitors whether the robot has picked up two pieces at once. This check is indispensable, because in exceptional cases the oiled, 0.8 mm thick sheets may stick to each other. The robot then holds the workpiece in the press brake and bends it into the desired shape, comprising a defined number of 125-degree and 90-degree angles. With some bending steps the KR 150 L110 has to use its full power to counteract the force exerted by the press. During the process, the robot changes the position of its gripper if necessary at a holding station equipped with pneumatically operated suction cups. The robot nestles the finished bent parts together on a europallet, first rotating every second workpiece at the holding station.

• Series 2000 KUKA robot KR 150 L110
• PC-based KUKA robot controller, including control panel with familiar Windows interface
• Suction cup gripper
• Software tool KUKA BendTech Pro V1.0 for offline programming 
• Robot programming
• Commissioning

• Greater efficiency through offline programming
  
  

  Integrated into KUKA BendTech Pro is a 3D simulation tool which can be used to model and display both the bending sequence and all of the other process steps. Because the components stored there can be parameterized freely, low-cost investigations can be carried out even during the simulation phase to determine whether they meet the requirements. Once the data of the workpiece to be bent have been imported into the simulation tool, the bending sequence software in BendTech Pro suggests the optimal bending sequence. The rest of the process takes place entirely within the simulation environment.

   

  The simulation can also be used to check for collisions, for reachability checks, and for quick analysis of cycle times. Furthermore, robot motions which in the physical world would have had to be retaught can be optimized ahead of time in the simulation. In addition, suggested bending sequences can be modified and tested using various tools.

   

  Because BendTech Pro models the entire process, these tools have significant advantages compared to tools from press manufacturers or purely software firms. Such tools are mostly developed for control and programming of only a single type of press. They are thus not adapted, for example, for checking the reach of a robot, or for warning about collisions between the robot and the workpiece, or between the workpiece and the press die. What is more, they lack the automatic synchronization of the interface between the robot and the press controller. In contrast, BendTech Pro even includes complete palletizing software.

   

  An important prerequisite for offline programming with BendTech Pro is the KUKA KR C2 robot controller, which can be used to control not only the robot, but also external axes. One of these external axes can be the press. The user therefore does not need a separate press controller, and no resources are required to synchronize two different controllers.
  
  
  
• Greater profitability
  
  In itself, the automation solution provides greater efficiency and more consistent quality. The main reason why automation has in itself led to greater cost-effectiveness is the almost total elimination of personnel costs.