Patent ID: 7886497

Claim:
A rectangular floorboard which is adapted to provide mechanical joining of said floorboard with similar or identical, adjacent floorboards, the floorboard comprises: a first locking device having a locking groove, wherein said first locking device does not extend beyond a vertical plane which is perpendicular to a principal plane of the floorboard and defined by the upper joint edge, and a second locking device having a projecting portion projecting beyond the vertical plane defined by the upper joint edge and parallel to the principal plane of the floorboard, and supporting a locking element designed to interact with said locking groove when said floorboard is joined with a similar or identical one of said adjacent floorboards, said first locking device is provided on a first short side of the floorboard, and said second locking device is provided on a second, opposite short side of the floorboard and on both long sides of the floorboard, such that said first short side of the floorboard is lockable only horizontally to both long sides and to the second, opposite short side of the identical floorboard, and thereby lockable only in a direction perpendicular to the respective joint edges and parallel to the principal plane of the floorboards.