Lock and key system with extra code combinations

A lock and key system including a lock comprising:

• a housing (204) having a cylindrical bore (203),
• a cylindrical key plug (202) being rotatably journalled in said cylindrical bore, said key plug having a longitudinal key slot (201) and, at a side of said key slot, a number of side locking tumblers (206) in a row cooperating with a side locking means (213) for locking the key plug against rotation in the cylindrical bore,
• at least one of said side locking tumblers (206) comprising a cylindrical body portion (206b) being mounted in an associated chamber (207) for elevational and rotational movement therein, and a finger (208) which projects transversely from said body portion (206b),
• said elevational movement being performed against the action of a force exerted along said chamber (207), and
• said rotational movement of the side locking tumbler (206) being caused by a pivotal motion performed by the associated finger (208), the rotational movement of the side locking tumbler (206) being limited between two angular end positions corresponding to a respective pivotal end position of the finger (208), and including a key (100) comprising:
• a longitudinally extending key blade (102), which is insertable into said key slot (201) of the key plug (202) of an associated lock (200),
• said key blade (102) having at a side (110s) thereof a side code pattern (105) which forms a wave-like guiding surface including a ramp portion (106) at the free end portion (107) of the key blade,
• said wave-like guiding surface (105) engaging with said finger (208) of said at least one side locking tumbler (206) and making the finger follow said wave-like guiding surface,
• the side locking tumbler (206) being caused to move elevationally while being acted upon by said force, and the finger (208) being caused to pivot sideways into specific pivotal positions, when the key blade is fully inserted into the key slot, characterized in that said transversely projecting, pivoting finger (208) of said at least one side locking tumbler (206) includes:
• a base portion (208b) having two opposite side surfaces (221,223) located at a distance being substantially smaller than the distance between two associated, opposite surfaces (218,219) in a channel (217) extending from said tumbler chamber (207) to said key slot (201), so as to enable a pivoting motion of the finger (208) between said two pivotal end positions, and
• an asymmetrical free end portion (208e) having a key contacting portion (220r;220l) which is displaced (d), in a circumferential direction, relative to a central plane (C) extending through the central axis (A) of said cylindrical body portion (206b) and centrally through said base portion (208b) of the finger,
• whereby the location of said key contacting portion (220r,220l) is positioned by way of a specific pivotal position of said finger (208) and a specific asymmetric displacement of said key contacting portion, and the number of possible code combinations is consequently further increased.