Patent ID: 7647743

Claim:
Method for making a floor panel that includes an upper side, an underside, and a first and second pair of opposite side edges that each include upper side edges adjacent the panel upper side; the first pair of side edges including coupling parts, said coupling parts being configured to enable two of such panels to be mechanically coupled to each other, said coupling parts being in the form of a tongue and a groove having locking elements including locking surfaces, said coupling parts and locking elements of said first pair of side edges providing a locking between coupled panels when a tongue of one panel is received in a groove of the other panel preventing separation of the panels in vertical and horizontal directions, said groove being bordered by an upper lip and a lower lip; the second pair of side edges including coupling parts also configured to enable two of such panels to be mechanically coupled to each other, said coupling parts of said second pair of side edges being provided with locking elements, said coupling parts and locking elements of said second pair of side edges providing a locking between coupled panels preventing separation of coupled panels in vertical and horizontal directions; comprising the steps: forming the coupling parts on said first pair of opposite side edges and on said second pair of opposite side edges in such a manner that on said second pair of side edges a firmer locking between the coupling parts is provided in the horizontal direction perpendicular to the related edges and parallel to the underside of the coupled panels than is provided at said first pair of opposite side edges and such that, at the first pair of side edges, said locking surfaces contact each other when a pair of the panels are coupled by placement of the tongue part of one panel into the groove part of the other panel with the upper side edges of the panels adjoining each other, to thereby secure the upper side edges of said coupled panels in adjoined relationship while preventing unintentional separation between the upper side edges that would produce undesired gaps between the upper side edges in a direction perpendicular to the related side edges and parallel to the underside of the coupled floor panels.