Abstract: A key switch operable by a cylinder lock, which switch comprises a cylinder housing and a cylinder core arranged to be rotatable within the housing, which is coupled with a non-conducting switch rotor and a switch casing base, in which the switching arrangement is located and the switch rotor is guided.The cylinder housing is made of insulating material and forms the top of the switch casing and, on its end face facing the switch rotor, has at least one annular rib which is concentric with the axis of the switch rotor, and which engages in an annular groove of the switch rotor, which groove has a corresponding contour.

Abstract: A locking device comprises a lock cylinder and a reversible flat key having indentations located on opposite broad faces of the key for the arrangement of tumbler pins, and having a rib associated with each row of indentations, into the sectional area of which at least one of the pins extends and the crest of which rib projects beyond the broad face of the key. The deepest reached indentation lies nearest to the crest of the rib and several indentations of a row of indentations are integrated into a through groove of variable depth levels.

Abstract: A cylinder-operable key switch 5 comprises a cylinder housing 1 and a cylinder core 7 mounted rotatably therein, which acts upon an electrical switching device 3. The switching device 3 is located at one side of and adjacent to the cylinder core 7 which operates the switching device 3 by rotation of a control member 18.The key switch is particularly suitable for fitting to electronic equipment, where it provides a high insulation against flash-over voltage.