Panel soldering with a specialised gripper in mini wave soldering

In such cases, specialists like Eutect GmbH are called in. Recently, the company was tasked with developing a specialised gripper to address a specific challenge in the mini wave soldering process.

"In this particular case, it was a relatively large PCB that was divided into four panels. Two THT capacitors had to be soldered to each individual panel, which were not allowed to bend during the process. As these were very large and high, they were quite unstable in their unsoldered state," explained Matthias Fehrenbach, Managing Director of Eutect GmbH. The challenge involved ensuring that the large PCB would not bend and that the capacitors remained firmly in place throughout the process. Fehrenbach added: "A standard inline mini-wave process was therefore out of the question."

Eutect’s team of process specialists responded by developing a gripper designed to both stabilise the components and prevent the PCB from bending.

Lars Iwers, a Sales Representative at Eutect, explained further: " Our customer specified that no bending force should act on the components. It was therefore necessary to feed the assembly absolutely straight to the respective processes." The gripper was developed with this requirement in mind. However, one complication arose: the panel was transported without a workpiece carrier and was positioned too close to the conveyor belt to allow for direct soldering beneath it.

To address this, the team designed the gripper to pick up the panel from the belt. During this step, the PCB was pressed against spacers from below, holding it straight. The capacitors were secured in position using component-specific hold-down devices. From there, the gripper transported the assembly to the IW 1 mini wave soldering module via an axis system. A titanium mask was mounted over the soldering nozzle to protect the board during the process. The nozzle itself was mounted on a spring base mechanism to ensure accurate positioning.

Fehrenbach noted the importance of this innovation: "The fact that we had to move a PCB panel without a workpiece carrier in this project required the gripper to have a special configuration. After all, a panel like the one in this case is relatively unstable, which is not very helpful for a reproducible soldering process."

The gripper’s design ensured that the PCB was fed into the soldering process in a stable and horizontal position, eliminating the need for a soldering frame typically used to stabilise panels during soldering. As a result, Eutect could fully meet the customer’s specifications.

Fehrenbach concluded: "Thanks to the special gripper, it is now possible to guarantee a reproducible and cycle time-optimised process."