Patent ID: 7665267

Claim:
A floor panel for forming a floor covering, which panel is rectangular, i.e. elongated or square, and has an upper side, an underside, and at least two opposite side edges including upper side edges adjoining the upper side, wherein said floor panel comprises a core material selected from the group consisting of medium density fiberboard and high density fiberboard; wherein said floor panel at said two opposite side edges is provided with coupling parts substantially in the form of a tongue and a groove, said groove being bordered by an upper lip having a distal end and a lower lip, wherein the coupling parts are configured so as to enable two of such panels to be coupled to each other with the tongue of one panel received in the groove of the other panel, and with the respective panel upper side edges adjoining each other; wherein said coupling parts are provided with integrated mechanical locking elements associated with the tongue and groove which prevent the drifting apart of two coupled floor panels in a direction perpendicular to the related edges and parallel to the underside of the coupled floor panels, the locking elements including locking surfaces that contact each other upon coupling of the panels; wherein at least said tongue and the respective locking element associated with the tongue are formed in one piece in said core material; said upper side edges, coupling parts and locking elements being configured such that said coupling of a pair of panels is achievable by a turning movement wherein one panel by its side edge is angled-in to the side edge of the other panel until a tongue of one panel is fully received in a groove of the other panel with the locking surfaces in contact with each other and such that uncoupling of the panels along one side edge of at least one pair of side edges is achievable by a reverse turning movement of one panel relative to the other about the respective side edge starting from a position where the upper side edges are in contact with each other; and wherein in coupled condition of two of such panels a space exists underneath the tongue, said space extending from the distal end of the tongue in a proximal direction of the panel wherein said locking surfaces contact each other when a pair of the panels are coupled by placement of the tongue of one panel into the groove 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 which 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.