Patent ID: 8156777

Claim:
A lock and key combination including; a cylinder lock with a rotatable key plug having a key slot for receiving a flat key blade, and a key ( 100 ) with said flat key blade, and at least two side locking tumblers ( 201 a , 201 b ; 301 , 302 ; 401 , 402 ) in said cylinder lock, said side locking tumblers being guided for at least one of elevational and rotational movement in associated chambers in said key plug and having transverse fingers ( 211 a , 211 b ; 311 , 312 ; 411 , 412 a , 412 b ) projecting into said key slot for engagement with said key blade, upon inserting said key into said key slot, and an associated code pattern ( 110 ) in a side recess ( 115 , 118 ) of said key blade for engagement with said side transverse fingers and positioning said side locking tumblers into positions that allow said key plug to rotate in said cylinder lock upon inserting a correctly coded key into the key slot, said fingers having different lengths, at least one having a first, short finger length projecting transversely from the side locking tumbler and at least one having a second, long finger length projecting transversely from the side locking tumbler, the short fingers engaging with a primary code surface having a number of first code surface portions at an external portion of said side recess of the key blade, and the long fingers engaging with a secondary code surface having a number of second code surface portions at an internal, deeper portion of said side recess of the key blade, wherein said transverse fingers are each located at a specific longitudinal position centered in relation to or longitudinally displaced from a transverse plane extending through a central axis of the associated chamber, and said first and second code surface portions of said key are specifically distributed longitudinally to allow said transverse fingers to be seated on said first and second code surface portions ( 111 , 112 ; 141 , 142 ; 151 , 152 ) upon inserting the key into the key slot, wherein said first and second code surface portions are located at distinct positions generally variable or separated in three dimensions in said flat key blade, namely: in a direction upwards and downwards in a vertical plane defining said flat key blade, in a depth direction perpendicular to said vertical plane, and in a longitudinal direction along said key blade, wherein a compact code pattern with an increased number of code combinations is formed on the key blade.