Floor panels with edge connectors

1. A floor panel having a laminated construction and comprising:

a core having an upper side, said core comprising a material selected from the group consisting of MDF and HDF;

one or more layers of material located at the upper side of the core, said one or more layers comprising at least one layer impregnated with resin;

an underside on which is disposed a backing layer constituting a counterbalancing element, said backing layer comprising a layer impregnated with resin;

said floor panel at least at the side edges of two opposite sides being provided with coupling parts substantially in the form of a tongue and a groove, and including upper side edges adjacent the panel upper side, said groove being bordered by an upper lip and a lower lip, said upper lip terminating at a virtual vertical plane, said coupling parts configured so as to enable two of the floor panels to be coupled to each other without play;

at least said lower lip being formed in one piece with said core material;

said coupling parts including integrated mechanical locking elements arranged to prevent the drifting apart of two coupled floor panels in a direction perpendicular to the related edges and parallel to the undersides of the floor panels when the panels are coupled together with the tongue of one panel received in the groove of the other panel with the locking elements engaged, and the upper side edges adjoining each other;

said locking elements comprising a first locking element located in said lower lip;

said lower lip having an underside and said backing layer extending substantially entirely along the underside of the lower lip from a proximal to distal end thereof;

said lower lip having a length such that the lower lip protrudes distally beyond the upper lip by a distance less than the thickness of the panel;

wherein the panel has a thickness of 0.5-1.5 cm; and

said first locking element comprises a locking surface located in a portion of said lower lip which is located distally beyond said upper lip, and bordering an upwardly facing recess in the upper side of the lower lip, said lower lip at said recess having a portion of minimum thickness between a bottom of the recess and the panel underside;

said recess extending proximally inwardly along an area of the lower lip at least up to said virtual vertical plane;

said tongue having an upper side defining a flat tongue contact surface and said lower side of said upper lip defining a flat upper lip contact surface, said tongue and upper lip contact surfaces contacting and cooperating with each other upon coupling of a air of the panels along their coupling parts;

said recess minimum thickness being smaller than a thickness of the upper lip at a point along said cooperating contact surfaces most proximally located under the upper lip relative to the upper lip;

said minimum thickness also being smaller than the distance between a first virtual horizontal plane intersecting the bottom of said recess at said lower lip portion of minimum thickness and a second virtual horizontal lane intersecting the lower side of the upper lip at the area of engagement of said tongue and upper lip contact surfaces most closely proximate to said virtual vertical plane.

2. The floor panel of claim 1 , wherein the layer or layers of material at the upper side of the core include a decorative layer.

3. The floor panel of claim 1 , wherein the layer or layers of material at the upper side of the core include a decorative layer as well as a protective layer.

4. The floor panel of claim 1 , including a second locking element comprising a protrusion at a lower side of said tongue, said protrusion including a tongue locking surface configured to contact and cooperate with said locking surface bordering said recess when two panels are coupled at said coupling parts with the upper side edges adjoining each other.

5. The floor panel of claim 4 , wherein said groove comprises a lateral cut in the respective edge of the floor panel, and wherein the recess comprises an inclined cut in the upper side of the lower lip.

6. The floor panel of claim 1 or 4 , wherein the coupling parts located at both said opposite edges are made in one piece with said core material.