Arrangement for air-layer fibre bodies on a moving air-permeable conveyor path

DETAILED DESCRIPTION This object is achieved in accordance with the invention by means of an arrangement of the kind defined in the introduction which is characterized in that between each pair of means arranged mutually sequentially in the movement direction and delimiting a stream of air-borne fibres there is provided a transition or bridging region into which ambient air can enter freely; and in that the means which generate a subpressure beneath the air-permeable conveyor path extend beyond the fibre-stream delimiting means and into the transition or bridging region.
Because the subpressure generating means extend into the transition region, there is formed a local subpressure at the limits of the transition region so that the pressure in the ambient air externally of the stream of air-borne fibres will be locally equal to the pressure in the stream, therewith eliminating the occurrence of transverse air-streams in the intermediate region between hoods and transition regions.
Because the fibre layer that passes through the transition region has already been laid, no inhomogeneities will occur in the layer as a result of the influence of the different sub-pressures in the two vacuum boxes.
According to one preferred embodiment of the arrangement in which the moving conveyor path is comprised of a succession of moulds having air-permeable bottoms and disposed around the periphery of a mat-forming drum and in which at least two mat-forming hoods which each coact with an individual vacuum box are mounted peripherally one after the other and radially outside the mat-forming drum, each pair of mat-forming hoods is separated from another circumferentially, so as to provide between the hoods a transition region into which air can enter freely , and the vacuum boxes coacting with the hoods extend into the transition region.
The vacuum boxes also extend circumferentially beyond associated mat-forming hoods on all sides thereof.