Fleece-Laying Apparatus

Abstract

In a fleece layer of the carriage cross-lapper type, the laying carriage conveyor belt (14) wraps around the first laying roller (12), the upper and lower strands (14o, 14u) of the belt being parallel to each other as they proceed from the first laying roller (12). An endless cover belt (23), which travels around in the laying carriage (5), wraps around the second laying roller (13), the cover belt having upper and lower strands (23o, 23u), which are parallel to each other as they proceed from the second laying roller (13) in the direction opposite that of the laying carriage conveyor belt (14). The mutual distances between the web entrance (8, 9), the upper carriage (4), the laying carriage (5), and the output conveyor belt (2) perpendicular to the transport directions of same are so small that the card web (11) to be laid is enclosed in a sandwich-like manner between the adjacent strands of the web entrance conveyor belt (6), of the upper carriage conveyor belt (20), and of the laying carriage conveyor belt (14), where the laid fleece on the output conveyor belt (2) is contacted by the laying carriage conveyor belt (14) and by the cover belt (23).

Description

CROSS REFERENCE TO RELATED APPLICATION[0001]This application claims priority to European patent application EP 07 006 703.8, filed Mar. 30, 2007.FIELD OF THE INVENTION[0002]The invention pertains to a fleece-laying apparatus, such apparatus sometimes being referred to herein as a “fleece layer.” This invention is a fleece-laying apparatus of the carriage cross-lapper type having a stationary web entrance, an upper carriage and a laying carriage in each of which a endless conveyor belt travels, and laying rollers which form a laying gap between them for delivering the card web to be laid to an output conveyor belt above which the two carriages are movably guided in a machine stand transversely to the transport direction of the belt.BACKGROUND[0003]A fleece layer of the type indicated above is known from “Vliesstoffe” (Nonwovens) by W. Albrecht, H. Fuchs, and W. Kittelmann (published by Wiley-VCH, Weinheim, 2000, p. 161). The advantage of this type of fleece layer is to be found in th...

AI Technical Summary

Benefits of technology

[0006]It is an object of the invention to provide a fleece layer of the type described above which, while maintaining the simplicity-intrinsic to the carriage cross-lapper—with which the belts participating in the web transport and web guidance processes are routed, avoids the effects which cause the fibers to be blown away and thus allows the machine to operate at a higher speed.

[0008]The cover belt traveling around in the laying carriage wraps around not only one of the laying rollers forming the boundary of the deposition gap but also around a deflecting roller supported in the laying carriage a certain distance away from the laying rollers. When supported so that its height is adjustable, this deflecting roller offers the possibility of taking into account in a special manner the direction in which the laying carriage is moving. That is, if the diameter of this deflecting roller is made smaller than that of the associated laying roller, then, by adjusting the height of the deflecting roller and by taking other measures to be explained in detail later, it is possible to give the cover belt optimal conditions for covering the laid fleece in both directions of movement of the laying carriage. It is effective to apply this feature also to the end of the laying carriage conveyor belt facing away from the laying rollers, so that the previously mentioned advantages are obtained in both directions of movement of the laying carriage.

[0010]The invention offers the previously mentioned advantage that the card web to be deposited is guided in the manner of a genuine “sandwich”. So that the fleece layer can be adapted to card webs of different thicknesses, according to an elaboration of the invention, measures may be provided by means of which the web-guiding belts can be adjusted in their height with respect to each other in the area between the web entrance and the upper carriage and also in the area between the upper carriage and the laying carriage—adjustments which can be realized very easily in the inventive fleece layer because of the simplicity of the belt routing. The distance between the belts can be made zero in these areas. For this purpose, it is sufficient for the paths along which the upper carriage and the laying carriage travel to be height-adjustable. The desired contact which the lower strand of the laying carriage conveyor belt and that of the cover belt make with the laid fleece can be produced by adjusting the height of the output conveyor belt and can extend all the way to light pressure.

Problems solved by technology

As a result, the card web is exposed to strong aerodynamic influences, which are caused by the movement of the carriages and which have the effect of blowing the fibers away and of causing the web to be deposited nonuniformly, especially at the edges of the laid nonwoven.

The two web conveyor belts cannot be routed so that they are parallel to each other at the lower deflecting roll in the upper carriage because different wrap-around radii are present, which would lead to frictional effects potentially damaging the guided card web.

What is obtained overall, therefore, is a very complicated routing of the two web conveyor belts in both the upper carriage and the laying carriage with a large number of belt deflection points.

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