IMPROVED CYLINDER LOCK AND KEY

摘要

A cylinder lock system employs a key which has a pair of projections extending from opposing parallel edges of the key blade. The keyway of the lock has an enlarged slot portion for receiving the projections upon insertion of the key. One of the projections cams pins of an auxiliary pin stack to present a shear line between the pins to permit rotation of the key plug to an unlocked mode. The other projection is received in a groove formed in the shell and is engageable against a surface of the groove upon rotation of the key to retain the key within the keyway.