Cylinder locks with locking pins having a hardened surface.

摘要

A cylinder lock having an inner barrel (5) rotatable in an outer cylinder (2) is lockable with spring loaded pins (4) which pins are of steel, are provided with a hard corrosion resistant carbide or nitride layer and the steel of which has been hardened. The carbide layer may be chromium carbide formed by chromizing. The steel pins may be carburized before chromising. The nitride layer may be chromium nitride formed by chromising of a steel which has been nitrided. The pins are hard and corrosion resistant and impart improved burglar proofness to the lock.