Abstract: A closure part for the liquid and dirt-sealed closure of a coupling socket for optical waveguides carries a central sealing element and a sleeve coaxially surrounding the sealing element. The sealing element includes an end surface having a bevel with a surface area adapted to an edging on an end surface of the coupling socket. The sealing element is pressed against the socket and seals the socket by suitable pressure. The sleeve grips in a firmly adhering manner around an outer lateral surface of the socket, fixes the closure part in an SC receptacle and seals the socket from the outside.

Abstract: In fiber-optical plug connections or guard plugs for electrooptical modules, detent arms are used to lock the connection. When such connections are undone, the detent arms are pressed out of their abutments and in the process are exposed to a severe mechanical stress, which can cause material fatigue. A disconnectable plug includes two spaced-apart outer walls that can be spread apart from one another. Through the use of a partition, the two outer walls are resiliently supported against one another in their middle region. In an insertion position, detent arms of plug partners are lockingly supported by the outer walls that have detent surfaces. In an unlocking position, the outer walls release the detent arms. The detent arms are stressed only by tension but not by flexion. Conversely, the partition receives the entire bending stress upon spreading. The disconnectable plug is especially suitable for guard plugs and connections in electrooptical modules.