Patent ID: 8082717

Claim:
A panel having a top face and a bottom face, opposite first and second longitudinal edges, opposite first and second transverse edges, and means for detachably connecting the panel to an identical adjacent panel by pivoting, the means comprising: a tongue provided on at least one of the first longitudinal edge and the first transverse edge of the panel so as to project beyond the respective one of the first longitudinal edge and the first transverse edge; the tongue having lower and upper tongue surfaces that divide the at least one of the first longitudinal and the first transverse edge into a top edge portion and a bottom edge portion, at least a portion of the lower tongue surface having a convex curvature; one of the second longitudinal edge and the second transverse edge having a groove corresponding to the tongue of the adjacent panel, the groove flanked by upper and lower panel edge regions of the panel; the lower panel edge region projecting toward the upper panel edge region, and the bottom edge portion being recessed with respect to the top edge portion; the tongue on the upper tongue surface having a projection with a contact surface directed rearward in a direction toward the top edge portion such that an angle between a normal to the contact surface and the top face being an oblique angle, and the upper panel edge region having on a lower side thereof a recess at least partially accommodating the projection and having a countersurface; the countersurface in a pivoted-in state cooperating with the contact surface of the adjacent panel so that the panels in the connected state as the result of pivoting-in have a connection that is free of play in the direction perpendicular to the orientation of the surfaces of the edge portions; and the panels when connected by pivoting-in are pulled together due to the cooperation of the contact surface and the countersurface of the panel and the adjacent panel.