Patent ID: 7431783

Claim:
A method for continuous production of plasterboard elements in which two cardboard-type paper sheets enclose, within shaping means, a plaster-based hydraulic binder to create a composite strip which then hardens on two hardening belts carrying at their edges two tapered strips for producing longitudinal tapered edges thereon, comprising: continuously preparing flexible, lightweight spacers or packing pieces between 1 and 2 mm thick and 5 to 20 mm wide, cutting said packing pieces to a length equal to a width of the plasterboard being produced less a value comprised between 0 and 10 cm, applying adhesive to an upper face of said packing pieces, continuously bonding said packing pieces on-the-fly to the bottom of one of said cardboard-type paper sheets transversely thereto, centered, and perpendicular to a direction of advancement of said paper sheet at accurate regular intervals, wherein during said bonding step, said packing pieces are bonded to said paper sheet in a region ahead of said shaping means, allowing said packing pieces to be carried along by said paper sheet, adjusting a tension in said paper sheet so as to regulate a width of an imprint created therein by the packing pieces to between 10 and 18 cm, leaving said packing pieces fastened to said paper sheet for the time needed to pass through said shaping means and the time needed for the composite strip composed of said paper sheets and the hydraulic binder to harden, and cutting the composite strip with knife means in the middle of the imprints left by said packing pieces.