For assembling/disassembling a printed circuit board, a specially shaped spring is to be integrated inside the device. The assembly/disassembly of the printed circuit board in the device is simplified by virtue of the fact that the printed circuit board has to be pressed only against the spring and a fixed supporting part of the device to which the spring is attached. In order to be able to press the printed circuit board, among other things, perpendicularly against the fixed supporting part, the specially designed leg spring is fastened underneath the fixed supporting part. The legs of this spring protrude outward on both sides beyond the top-side of the supporting part. During assembly, the printed circuit board is guided between the top-side and the protruding spring legs. The printed circuit board is fixed by additional supporting parts of the device.