Patent ID: 7958760

Claim:
A lock and key system including locks of the kind comprising: a housing ( 200 ) having a cylindrical bore ( 202 ), a cylindrical key plug ( 203 ) being rotatably journalled in said cylindrical bore, said key plug having a longitudinal key slot ( 204 ) and a number of locking tumblers ( 205 ) in a row along a key plug axis for locking the key plug against rotation in the cylindrical bore, at least a subset of said locking tumblers comprising a body part ( 206 a ) and an integral key sensing part ( 206 b ) for engagement with an associated key ( 100 ), said body part being mounted in an associated chamber ( 208 ) in said key plug for elevational movement therein along a tumbler axis in parallel with an axis of said associated chamber, and keys of the kind comprising: a longitudinally extending key blade ( 102 ), which is insertable into said key slot of the key plug of an associated lock, said key blade having at least one longitudinal code pattern ( 103 ), including a number of code portions ( 104 ) for engaging with said integral key sensing part of said locking tumblers and making the key sensing part follow said longitudinal code pattern, when the key blade of said associated key is being inserted into the key slot, wherein said longitudinal code pattern of the key blade ( 102 ) comprises a longitudinal row of code concavities ( 104 ), and the integral key sensing part ( 206 b ) of each locking tumbler in said subset comprises at least two neighbouring key code contacting portions ( 210 a , 211 a ) in the form of at least two projecting key code contact surfaces forming sensing portions on the locking tumbler adapted to mate with respective code concavities, said at least two projecting key code contact surfaces ( 210 a , 211 a ) forming separate extreme ends of each locking tumbler and have tips on key code contact surfaces wherein the extreme ends with said tips are substantially parallel to each other and are mutually displaced from each other longitudinally along said key plug axis, at a mutual distance not exceeding ¾ of the distance between the central axes of two adjacent locking tumblers in said row, and each such key code contact surface being provided with smooth edges for possible sliding engagement with said longitudinal row of code concavities ( 104 ) in an associated key, when the latter is being inserted into said key slot, the number of code concavities in said longitudinal row in said associated key corresponding to the number of projecting key code contact surfaces of the locking tumblers in said row, said number of projecting key code contact surfaces and code concavities being at least twice the number of locking tumblers in said subset, and at least one of the tips of said projecting key code contact surfaces of each locking tumbler in said subset only engaging with a corresponding code concavity in said associated key and being elevationally and rotationally positioned at an exact code location upon fully inserting said key into said key slot.