Patent ID: 7003924

Claim:
A parquet board with a groove and tongue edge profile comprising an upper decorative surface atop a core, a projecting tongue on at least one edge of the parquet board and a receding groove on at least one other edge of the parquet board, wherein the top edge of the tongue is provided with a projecting locking lip running in the longitudinal direction of the tongue, and a corresponding locking recess is provided running in the longitudinal direction of the groove, the edge of the parquet board defining the groove comprising a top groove cheek and a bottom groove cheek, and said recess is formed in a lower portion of the top groove cheek, said top and said bottom groove cheeks defining an entry for the groove, the bottom groove cheek being shorter than the top groove cheek, a gradation is provided on the bottom groove cheek which widens only a portion of the groove and a tapered surface is provided between said widened portion of the groove and the remainder of the groove, the tongue is provided in its root portion with a section of greater thickness than the remainder of the tongue forming a thicker tongue portion, the thickness in the remaining portion of the tongue being connected to said thicker tongue portion via a linear tapered surface, whereby when the locking lip enters a groove of an adjacent parquet board, the groove of the adjacent parquet board having the same shape as the groove of the parquet board, during assembly of the parquet board with the adjacent parquet board, the thicker portion of the tongue is not yet engaged in the graduated portion of the groove so that the parquet board having the tongue can be displaced slightly downwards to facilitate the passage of the locking lip into the groove and the upper surface of one parquet board can be laid jointlessly with an upper surface of an adjacent parquet board.