Verfahren zum Beleimen von Fasern

NOVELTY - To coat fibers with an adhesive, the adhesive is applied while the fibers have a residual moisture content of at most 100%. After the application of the adhesive, the fiber clumps are broken down. DETAILED DESCRIPTION - In an INDEPENDENT CLAIM, an assembly has a tower (4) which can be filled (18) and emptied (20). The adhesive is applied to the fibers in the tower through feeds (8) in the tower or its wall (6). A mechanism (22) to break down fiber clumps is at the outlet of the tower. Before application, the residual moisture content in the fibers is set by drying at at most 100% and pref. 10-1%. The fiber clumps are agitated in an air stream, giving turbulence which breaks them down in the air eddies. Or the glued fibers can be separated in a refiner or mill. The separated fibers are passed to a workstation to be formed into fiber materials. The fibers, in clumps or separated, can be fed to an intermediate store. The adhesive is applied to the fibers in a fiber/air stream mo ving at a speed of at most 150 m/s and pref. at most 50 m/s and especially at most 10 m/s, moving on a straight or a spiral path. The environment is controlled, in the application zone, to a given temperature and/or air humidity. The residual moisture content of the fibers can be varied while the fibers are being glued and/or separated. The adhesive glue is fed according to batches of fed fibers or fiber masses, or the vol. of delivered adhesive is set on a time scale. The adhesive is delivered by jets. The tower has a jet system (14) for the delivery of air or other gases into it, or through its walls, and also jets to generate air turbulence to eddy and/or advance the fibers. The tower is vertical, horizontal or at an angle, and is at least partially conical. The fiber clumps are broken down by a rotor, sieve, beating plate or the like, followed by winnowing where surplus air is diverted from the fiber/air stream for at least partial return to the tower after its temp. and/or humidi t y levels have been set. A control registers the fiber feed to set the volume of adhesive to be delivered by fiber batches or on a timed basis. The control system also sets the conditions of the environment within the tower according to the fiber moisture content and its mass, to give a temperature and/or humidity profile between the tower entry and exit. The consistency of the adhesive is adjusted according to the wetness and/or temperature of the fibers to be coated. USE - The method is for the preparation of wood fibers for use in fiberboards, and the like, where their adhesive coating gives a bond between them in the board structure. ADVANTAGE - The method reduces adhesive consumption, so that the fibers are effectively coated with minimum material and energy costs.