PressFit - Making stable connections with pressure

"Rarely has the interest in our GCell PressFit systems been as great as this year," Jeannette Engel, PressFit project manager, and Matthias Leyerer, head of BU Automation, agree.

The first PressFit systems were sold to our customers as early as 2009 - around 25 by 2018.At the beginning, we integrated presses that mostly had to join products with only a few PINS. Here, sensors are mainly pressed into control units, for example for airbags, various driver assistance systems or the rear view camera, etc.

But what makes our newly developed GCell PressFit system so special? To answer this, a conversation with Norbert Zinnöcker, who has been working as a design engineer at GEFASOFT since July 2012, will help. He looks intently at the monitor.On the left screen "his baby", the third generation PressFit system, which we have been building for our customers like this since 2018.After a design period of half a year, the first PressFit system was available in 2017.

Mr. Zinnöcker, what were the challenges you faced with this installation?

"The system had to be able to press up to 300 plug connections at the same time, so the biggest challenge is that everything is in the press center, nothing gets tilted. A guide system had to be designed so that even the edge points are pressed securely. The system had to have a threading control so that all pins find their way into the hole. A powerful industrial camera in combination with infrared incident light strips checks whether the parts are inserted correctly. The specification was also that the tools could be changed by hand and without further aids within a short time (less than 3 minutes)."

Our GCell PressFit system can always impressively demonstrate the high quality standard, especially when circuit boards with combined control and power sections with complex connectors are pressed.

The blanks and connectors are placed on a rotary table at the front, and a camera, the so-called AOI station (Automatic Optical Inspection), checks whether the worker has inserted the correct components in the correct position in the lower die. The rotary table then continues to cycle through 90°.

In the 2nd station, below the 2D scan box, the data matrix codes are read out. Additional laser sensors check whether all components to be pressed, i.e. connectors and boards, are correctly positioned in relation to each other in the mold.

In the 3rd work step, the multipins are pressed together with the PCB.

In the 4th station, our 3D image processing checks whether all pins have really been pressed correctly. In the fourth cycle, the pressed part rotates back to its original insertion position. The system operator can now manually remove the pressed part from the machine and reload the mold with components. The insertion and removal process can be implemented with different levels of automation depending on your requirements.

All process data is automatically documented by the system so that, in the event of differences, it is possible later to trace exactly where the possible error lay.With the GCell PressFit system, we use our own servo presses, which were also designed by Norbert Zinnöcker. "In joining technology, press connections are the most proven thing there is," he knows.Pressing parts instead of soldering has several advantages: vibration-proof connection, safe process, no solder, no "heat stress" for the PCB, no silicone problems, short cycle times. In addition, pressing is more sustainable than soldering: solder is toxic! Pressing requires much less energy than soldering, and the solder must be heated to several hundred degrees.

We supply our GCell PressFit system in three variants: 10 kN, 30 kN and 60 kN.

"We are keeping a close eye on developments in PressFit and must not slacken our efforts to further improve our equipment." Christian Schärtl, CTO at GEFASOFT, said.