Smart universal gripper for power electronics

Power electronics play a major role in an increasingly electrified world. The aim is to make electric drive systems as efficient as possible so that energy can be used sparingly and sustainably. Semikron Danfoss manufactures power modules, semiconductor components, switches, stacks and systems for automotive engineering, transportation systems, industrial plants and renewable energy applications. "Our aim is to offer high-performance electronic modules so that users can reduce their_{CO2 emissions}," explains Hanno Bruss, Test Engineer at Semikron Danfoss Elektronik in Nuremberg. "State-of-the-art electronic components are the basic prerequisite for this in order to ensure that the electrical systems function perfectly and operate efficiently. For us in production, the focus is therefore on zero-defect production, compact power electronics designs and high output power."

Universal gripper at a central process position

Measuring and testing technology therefore plays a central role at Semikron Danfoss. "Every single module that is produced here undergoes a comprehensive functional check. It goes without saying that only one hundred percent iO parts leave the company." Gripping technology from Schunk plays a key role in this quality assurance. In a closed automation cell upstream of a measuring line, the mechatronic parallel gripper EGU handles electronic components on a Scara robot. They arrive in tray stacks and reach the inside of the cell via a destacking unit. Here, the gripper on the robot removes the components individually from the blister tray and places them on a narrow conveyor belt to feed them to the measuring line. This puts the parts through their paces by carrying out a comprehensive final measurement of static, optical, tactile, dynamic and electronic parameters. The results of each individual module are documented and stored. At the end of the quality control in the approximately 6 m long measuring line, the removed modules are laser-marked and stacked back into trays to be finally packed as finished goods.

The throughput depends on the parts and the number of parameters to be measured. The measuring line currently operates in three shifts from Monday to Friday. "The linchpin of this system is the continuous and reliable feeding of the components out of the robot cell," says Hanno Bruss. "The gripper is therefore of particular importance." The system at the Nuremberg plant has been working with an electric gripper from Schunk for a few years now. "We have been working with Schunk for a long time," confirms Bruss. "We have Schunk grippers in use in many other places. A model was installed on this cell that was discontinued. And that's how the EGU came into play, which convinced us right from the start." The first inspection of the new electric parallel gripper took place at the SPS in 2022. "I was given a product to try out straight away and was able to test it in practical use," says the experienced test engineer. "The gripper was right from the start and met all our requirements."

Impressive functionalities for power electronics

The requirements for the gripper are very specific: "Firstly, we are limited in terms of weight due to the robot application. The EGU complies with this weight limit," explains Bruss. "Secondly, we need a large gripper stroke from very small to large, from around 30 to 110 mm. This flexibility was a decisive factor in our choice." Hanno Bruss emphasizes that there are always different parts to be handled and that the gripper flexibility also affects the workpiece variance. "That's why a servo-electric gripper is the right choice here."