Patent ID: 8720241

Claim:
A cylinder lock and key combination, including a cylinder lock ( 100 ), comprising: a housing ( 104 ) having a cylindrical bore ( 103 ) accommodating a rotatable key plug ( 102 ), said key plug ( 102 ) having a longitudinally extending keyway ( 101 ) for receiving a key blade ( 202 ), a row of tumbler pins ( 111 , . . . , 116 ) arranged for elevational and rotational movement in corresponding cylindrical chambers ( 111 a , . . . , 116 a ) in said key plug ( 102 ) for engagement with coded V-cut bittings ( 211 , . . . , 216 ) on an upper edge of an associated key upon insertion thereof into said keyway ( 101 ), and a longitudinal side bar ( 150 ) which is slidingly journalled for transversal movement in said key plug ( 102 ), said side bar having an outer, longitudinal ridge portion ( 160 ) fitting into an associated groove ( 105 ) in said housing, so as to normally prevent rotation of said key plug ( 102 ) in said cylindrical bore of the housing, said side bar ( 150 ) also having a row of inner projecting lugs ( 151 , . . . , 156 ) each selectively registering with one or more recesses ( 111 h , . . . , 116 h ) in said tumbler pins when said key has been inserted into the keyway ( 101 ), said side bar ( 150 ) being movable sideways by turning of a correctly cut key, while said projecting lugs enter into an one of associated tumbler pin recesses so that said longitudinal ridge portion ( 160 ) is released from said groove and the key plug ( 102 ) is permitted to rotate relative to said housing ( 104 ), and a key ( 200 ), comprising said key blade ( 202 ) having: an upper edge provided with said coded V-cut bittings ( 211 , . . . , 216 ), wherein: each of the lugs in said row of inner projecting lugs ( 151 , . . . , 156 ) of said side bar ( 150 ) is located at a relatively high level, above a rotary axis (A) of the key plug ( 102 ), when being moved sideways with the side bar ( 150 ) into the respective tumbler pin recesses ( 111 h , . . . , 116 h ), whereas the outer longitudinal ridge portion ( 160 ) of the side bar ( 150 ) is located at a substantially lower vertical level than the inner projecting lugs ( 151 , . . . , 156 ), namely at substantially a same vertical level as the rotary axis (A) of the key plug ( 102 ), seen in a central vertical plane (P) in the keyway ( 101 ), when the outer longitudinal ridge portion ( 160 ) engages with the associated groove ( 105 ) in the housing ( 104 ), and said tumbler pins ( 111 , . . . , 116 ) are configured so that each of said pin recesses ( 111 h , . . . , 116 h ) is located entirely above the rotary axis (A) of the key plug ( 102 ) and also entirely above a lowermost end portion of the tumbler pin ( 111 , . . . , 116 ) in a cylindrical outer surface of the tumbler pin and is covered by a cylindrical wall part of an associated one of said cylindrical chambers ( 111 a , . . . , 116 a ), without communicating downwardly with the keyway ( 101 ), whereby each pin recess is concealed and invisible from an inside of said keyway, even when the keyway ( 101 ) is empty.