Patent ID: 6851292

Claim:
A key-lock system, comprising: a flat-sided key insertable into a keyway of a cylinder core, the keyway provided with grooves and ribs corresponding to ribs and grooves of the key, wherein the key and the key way are subdivided into different profile sections extending from a key spine to a key facing, wherein a middle profile section of the key is provided with at least one groove at one side of the keyway and assigned to a rib on an opposite side of the keyway, the grove and the rib each bordered at one end thereof with a flank extending substantially perpendicular to a center plane of the keyway, and at another end bordered by a flank extending slantingly to the center plane so that the substantially perpendicular flank of the groove is confronting relationship to the slanted flank of the rib and the substantially perpendicular flank of the rib is in confronting relationship to the slanted flank of the groove, and wherein at least one of the ribs project beyond a central axis of the keyway.