Abstract: The present invention relates to a method and apparatus for producing a formed structural element of fiber material bonded with synthetic resin such that a fine-grained or flowable synthetic resin bonding agent is sprinkled on or sprayed on a nonwoven fabric made entirely or predominantly of natural fibers. The nonwoven fabric which is permeated with synthetic bonding agent is fragmented, whereupon the parts are stored in a tower on a perforated female mold which belongs to a molding press and are precompressed on the female mold by means of an air stream that is suctioned through the perforations. To produce formed structural elements with a stable shape, the synthetic resin bonding agent, after a similarly perforated male mold has been placed on top and pressed on, is hardened by means of a hot air stream that is conducted through the perforations in the male mold and the female mold.

Abstract: The structural element contains a first sound-absorbing and thermally insulating layer (21) and a second sound-insulating, dimensionally stable supporting layer (23). Preferably, the first layer consists of a thermoformed fibre mat or a foam which is at least partially open-cell, and the second layer consists of a rigid, thermoformed synthetic material, for example a plastic material reinforced with glass fibres. A porous or microporous decorative layer (22) can be applied to the outside of the first layer and a thermoformed carpet (24) can be applied to the outside of the supporting layer. A heat-sealable adhesive layer (27) can be placed between the two layers, the said adhesive layer incrasing the bond between the two layers.

Abstract: The process for the production of double-walled mouldings for the reduction of sound in vehicles and engines in general by means of a single pressing operation consists in introducing into a compression mould a double package, each individual package consisting of a layer of prepolymer fibres and a foil of thermoplastics material. The foils of the individual packages are situated facing one another and a medium under pressure is blown in between these foils, in order to cause each package layer to be pressed against the internal face of the corresponding half-mould. The compression mould is heated to a temperature which is sufficient to cause complete melting of said foil and complete polymerization of said prepolymer fibres.