Patent ID: 7954295

Claim:
A rectangular wood or laminate floorboard provided with a mechanical locking system for mechanical joining, vertically and horizontally, of the floorboard with similar floorboards along its long edges as well as along its short edges, wherein the mechanical locking system on at least one pair of parallel long edges or short edges comprises a tongue-and-groove joint, the groove and tongue of which having cooperating upper abutment surfaces and cooperating lower abutment surfaces for vertical locking of two joint edges of two adjacent floorboards, said upper and lower abutment surfaces being essentially parallel with the principal plane of the floorboards, said locking system comprising, for horizontal mechanical joining of the joint edges in a direction perpendicular to the joint edges, a locking groove formed in the underside of a first one of the joint edges and extended in parallel therewith, and a portion projecting from the second joint edge and integrated with a body of the floorboard, said projecting portion supporting, at a distance from the joint edge, a locking element cooperating with the locking groove, wherein said tongue is anglable into the groove, and wherein the locking element is insertable into the locking groove by mutual angular motion of the boards about the joint edges, wherein the mechanical locking system on said at least one pair of parallel long edges or short edges is designed such that: the projecting portion is formed in one piece with the body of the floorboard, in a joined state, the cooperating upper abutment surfaces are limited horizontally inwards from the joint edge and horizontally outwards to the joint edge by an inner vertical plane and an outer vertical plane, respectively; the tongue-and-groove joint is so designed that there is in the groove, in the joined state, between the inner and the outer vertical plane and below the tongue, a space which extends horizontally from the inner vertical plane and at least halfway to the outer vertical plane; the tongue-and-groove joint is further so designed that the boards, during a final phase of the inwards angling when the locking element is inserted into the locking groove, can take a position where there is a space in the groove between the inner and the outer vertical plane and below the tongue; and the lower abutment surfaces are positioned essentially outside the outer vertical plane.