US20080235915A1

US20080235915A1 - Fleece-Laying Apparatus

Info

Publication number: US20080235915A1
Application number: US12/056,982
Authority: US
Inventors: Johann P. Dilo
Original assignee: Oskar Dilo Maschinenfabrik KG
Current assignee: Oskar Dilo Maschinenfabrik KG
Priority date: 2007-03-30
Filing date: 2008-03-27
Publication date: 2008-10-02
Also published as: CN101275313A; EP1975286A1

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 (14 o, 14 u) 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 (23 o, 23 u), 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

This application claims priority to European patent application EP 07 006 703.8, filed Mar. 30, 2007.

FIELD OF THE INVENTION

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

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 the extremely simple way in which the belts participating in the transport of the card web are routed. Nevertheless, the route taken by the card web through the layer is open, and so is the deposition of the web on the output conveyor belt. 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 working speed of a fleece layer of this type is therefore very limited, for which reason this type of layer has been displaced by double-belt fleece layers, in which the card web, as it travels through the machine, is guided horizontally between two belts, one on each side, which explains why this is called a “sandwich layer”. In the layers of the type just described, these belts also serve as a covering for the nonwoven which has been deposited on the output conveyor belt and thus protect it from the previously mentioned air turbulence.
A fleece layer of the so-called “sandwich” type is known from EP 0 865 521 B1, in which a card web conveyor belt supplying the card web is routed both through the upper carriage and through the laying carriage and then continues through an auxiliary carriage, which can be moved back and forth underneath and transversely to the output conveyor belt. This auxiliary carriage supports a tensioning roll and serves to keep the card web conveyor belt under tension. A second card web conveyor belt is also routed through the upper carriage and the laying carriage and then passes through a second auxiliary carriage, which can be moved back and forth underneath and transversely to the output conveyor belt in the machine stand. This auxiliary carriage supports another tensioning roll and serves to keep the second card web conveyor belt under tension. In the upper carriage, the web-supplying, first-mentioned web conveyor belt travels over two rolls, which are arranged at different heights and which are offset from each other transversely to their axial direction, so that the web entrance slants downward. This slanted web entrance in the upper carriage is accompanied by the second web conveyor belt, which proceeds from there to the area between the upper carriage and the laying carriage, where it extends parallel to the first web conveyor belt, together with which it encloses, sandwich-like, the card web to be deposited. 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. The second web conveyor belt is therefore routed through the upper carriage over a total of four separate deflecting rollers in the area of the previously mentioned lower deflecting roller before it approaches the first web conveyor belt again. Corresponding measures are also taken for the first web conveyor belt in the laying carriage, because this belt, for the same reasons as those explained above, cannot be guided together with the second web conveyor belt into the laying gap in the laying carriage.
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.

SUMMARY OF THE INVENTION

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.
In contrast to the known carriage cross-lapper, the route taken by the web in the inventive fleece layer from the web entrance to the deposition point on the output conveyor belt is no longer open but rather closed, comparable to the situation in the “sandwich” layer. This means that the fibers cannot be blown away by the aerodynamic effects caused by the movements of the carriages and belts. At the same time, however, the simplicity with which the belts are routed is retained. There is therefore no longer any need for the auxiliary carriages of the known sandwich layer, which are required to make the movements of the main carriages independent of each other so that they can compensate for the difference between the web entrance speed, which is uniform, and the web deposition speeds, which necessarily change at the points where the laying carriages reverse their direction of movement. The invention also adds to the fleece layer an endless cover belt, traveling only in the laying carriage, to prevent aerodynamic or mechanical influences in the small gap between the laying carriage and the output conveyor belt from damaging the fleece which has been deposited on the belt. The invention makes it possible for the lower strands of the laying carriage conveyor belt and the cover belt to lie on the laid fleece.
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.
According to another aspect of the invention, the web entrance, which can but does not have to slant downward, is held stationary as conventional in the case of carriage type cross-layers. The card web travels from the web entrance to the upper carriage conveyor belt traveling around in the upper carriage. This belt is preferably air-permeable, so that the entrained air carried along by the web can escape as easily as possible. This helps to prevent the fibers from being blown away. From the upper carriage conveyor belt, the card web is transferred at a deflecting point to the laying carriage conveyor belt, which is traveling around in the laying carriage and which, together with the lower strand of the upper carriage conveyor belt, conducts it to the deposition gap. The web entrance conveyor belt bringing the card web into the entrance area accompanies the web as far as the deflection point at the upper carriage. There, however, it can be guided to the upper strand of the laying carriage conveyor belt, possibly by way of an additional deflecting roller, to avoid the frictional effects caused by different radii of curvature, and then to another deflecting roller, which is mounted at the same height as the deflecting roller which deflects the upper carriage conveyor belt at the point where the web is deflected onto the laying carriage.
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.
The invention is explained in greater detail below with reference to an exemplary embodiment, which is illustrated in the drawing.

DESCRIPTION OF THE DRAWING

The single drawing shows a schematic diagram of an embodiment corresponding to the invention.

The drawing shows only the most essential elements of the invention, namely, those which are necessary for explanatory purposes. Unnecessary items have been omitted so as not to overload the drawing with details which are not necessary to explain the invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

The drawing shows a schematic diagram of a fleece layer, consisting of: an output conveyor belt 2, supported in a lower stand 1, this belt being symbolized schematically by its deflecting roller and designed in the form of, for example, a slatted belt; an upper carriage 4, which can travel back forth in a machine stand 3 (illustrated schematically) transversely to the transport direction of the output conveyor belt 2; and a laying carriage 5, which can travel back and forth underneath the upper carriage, also transversely to the output conveyor belt 2.
In the example shown here, a web-carrying conveyor belt, called the web entrance conveyor belt 6 in the following, which travels over several deflecting rollers supported in the machine stand 3, runs through the upper carriage 4. The web conveyor belt 6 does not travel through the laying carriage 5 but rather above it and past it. If desired, it can also travel past the upper carriage 4 without accompanying the card web 11 to be transported all the way to the laying carriage 5.
The web entrance is stationary and, in the example shown here, has two deflecting rollers 8 and 9, which are arranged at different heights and with a certain lateral offset from each other, so that a downward-slanting web entrance is obtained. At the lower deflecting roller 9, the web entrance conveyor belt 6 is deflected by more than 90°, and opposite it at this point is preferably a stationary but resilient web guide device 10, which serves to improve the guidance of the card web 11 being brought up by the web entrance conveyor belt 6 and which is also preferably air-permeable, so that entrained air can escape unhindered from the card web.
Two deflecting rollers 18 and 19, which are parallel to each other, thus forming a gap between them, are supported in the upper carriage 4. A first endless web guide belt, called the upper carriage conveyor belt 20 in the following, wraps around the first deflecting roller 18. The belt also runs over a third deflecting roller 21 supported in the upper carriage 4. Parallel to the two gap-forming deflecting rollers 18 and 19, furthermore, a fourth deflecting roller 22 is supported in the upper carriage 4. The upper carriage conveyor belt 20 is preferably air-permeable; it can be designed as a traveling screen, for example, as a result of which the air squeezed out of the card web by the sandwich-like enclosure of the card web between the web entrance conveyor belt 6 and the upper carriage conveyor belt 20 can escape without hindrance. This has the effect of preventing the fibers from being blown away.
The upper carriage 4 is guided on a guide device, which is mounted in the machine stand and is preferably height-adjustable. In this way, it is possible to change the distance between the upper strand 20 o of the upper carriage conveyor belt 20 and the section of the web entrance conveyor belt 6 situated opposite it, so that, for example, it can be adapted to suit the thickness of the card web 11 being processed.
From the lower deflecting roller 9 at the web entrance, the web entrance conveyor belt 6 supplying the card web 11 runs in a direction parallel to the upper strand 20 o of the upper carriage conveyor belt 20 traveling around in the upper carriage 4. The web entrance conveyor belt then runs over and past the first and second gap-forming deflecting rollers 18 and 19, wraps around the fourth deflecting roller 22, and then travels over the second gap-forming deflecting roller 19, from which it proceeds in a direction parallel to the output conveyor belt 2. It then returns to the web entrance 8, 9 by way of stationary deflecting rollers, at least one of which, e.g., roller 28, is motor-driven. This conveyor belt can also be air-permeable.
The distance between the deflecting rollers 18 and 21, over which the upper carriage conveyor belt 20 runs, is based on the length of the card web section to be deposited between the deflecting rollers 18 and 21 onto the upper carriage conveyor belt 20, which is determined by the travel of the upper carriage 4, that is, by the laying width. The laying width is normally considerably smaller than the distance between the deflecting rollers and corresponds to the maximum usable width of the output conveyor belt 2. It is favorable for the upper strand 20 o of the upper carriage conveyor belt 20 to be supported from below, such as by a smooth plate 26, to prevent the belt from fluttering and thus causing effects which could blow the fibers away.
The laying carriage 5 is mounted underneath the upper carriage 4, and, like the upper carriage 4, it can be moved back and forth transversely to the transport direction of the output conveyor belt 2 above that belt in the direction of the arrows X. A first laying roller 12 and a second laying roller 13 are supported rotatably a short distance apart in the laying carriage 5. The laying carriage conveyor belt 14 traveling around in the laying carriage 5 wraps around the first laying roller 12; this belt also runs over a deflecting roller 15 of reduced diameter, supported a certain distance away from the first laying roller 12, and over a belt spreader 16, which is formed by two guide rollers 16 of reduced diameter. A cover belt 23, also traveling around in the laying carriage 5, wraps around the second laying roller 13, which forms the other boundary of the laying gap; this belt runs over an additional deflecting roller 24 of reduced diameter and a belt spreader 25, formed by two belt guide rollers of reduced diameter. “Reduced diameter” here means a diameter which is smaller than that of the laying rollers. At the two laying rollers 12 and 13, a laying gap is formed between the two belts 14 and 23 traveling around in the laying carriage.
The belt spreaders 16 and 25 serve to keep sections of the upper and lower strands 14 o, 14 u; 23 o, 23 u of the belts 14 and 23 traveling around in the laying carriage 5 parallel to each other, namely, the sections which extend between the spreaders and the associated laying rollers 12 and 13. The deflecting rollers 15 and 24 of these belts 14 and 23, namely, the rollers which are farther away from the laying rollers 12 and 13 than the spreaders are, are height-adjustable, as illustrated by the double arrows Y in the drawing.
The laying carriage conveyor belt 14 wrapping around the first laying roller 12 forms a certain belt section between the lower belt guide roller of the belt spreader 16 and the deflecting roller 15 farther away from the first laying roller 12; when the laying carriage 5 is moving to the left, this section slants upward, because, in this situation, the deflecting roller 15 has been brought into the raised position shown in the drawing. In this direction of movement, the deflecting roller 24 of the cover belt 23 is lowered, as shown in the drawing, so that the lower strand 23 u of the cover belt 23 is able to cover the full width of the fleece web produced by the deposition of the card web. In the opposite direction of movement of the laying carriage 5, the deflecting roller 15 is lowered to the level of the lower belt guide roller of the belt spreader 16, whereas the deflecting roller 24 is raised to the level of the upper belt guide roller of the belt spreader 25. The upper strands 14 o, 23 o of the belts 14, 23 traveling around in the laying carriage 5 are preferably supported from below in their horizontal sections, such as by smooth plates 27, to prevent the belts from fluttering.
Comparable to the upper carriage 4, the laying carriage 5 is guided in the machine stand on a guide device (not shown), which is preferably mounted in the machine stand so that its height can be adjusted. In this way, the distance between the lower strand 20 u of the first web guide belt 20 and the upper strands 14 o and 23 o of the laying carriage conveyor belt 14 and the cover belt 23 can be adjusted.
To adjust the distance between the lower strands of the latter belts 14, 23 and the output conveyor belt 2, it is advisable for the height of the output conveyor belt 2 on the lower stand 1 to be adjustable.
Because, as will be explained further below, the height adjustment of the deflecting rollers 15 and 24 takes place as a function of the direction of movement of the laying carriage 5, adjusting devices (not shown) are mounted in the machine stand 3, which selectively actuate drivers (not shown) attached to the deflecting rollers 15, 24 or to movable frames which hold the rollers, so that the actual height of the deflecting rollers 15, 24 is the result of the current position and direction of movement of the laying carriage 5. The devices can be of pneumatic design, for example. Each of the deflecting rollers 15 and 24 can also be supported on a pivot arm, each of which is supported in the space enclosed by the belts 14 and 23, and each of which is under the influence of tension springs anchored in the laying carriage 5 or possibly only under the influence of the tensile forces proceeding from the belts 14 and 23 themselves. The forces of the springs or belts secure the deflecting rollers 15 and 24 in their upper or lower end positions, which thus become stable positions, whereas the intermediate positions are unstable, which means that the adjusting devices merely initiate the change in height. Once initiated, the rest of the movement occurs automatically.
A card web 11 supplied to this fleece layer takes the following route through the inside of the machine: It is carried along on the web entrance conveyor belt 6 which supplies the card web 11 as far as the lower deflecting roller 9 of the stationary web entrance, where its position on the web entrance conveyor belt 6 is possibly stabilized by the guide device 10, which is stationary but movable in itself, i.e., resilient. The web is then transferred by the lower deflecting roller 9 of the web entrance onto the upper carriage conveyor belt 20 of the upper carriage 4. From there, the card web 11, the bottom side of which is now covered by the upper carriage conveyor belt 20 of the upper carriage 4, whereas the top side is covered by the web entrance conveyor belt 6, travels toward the gap-forming first and second rollers 18 and 19 of the upper carriage 4. At this point, the web entrance conveyor belt 6 loses contact with the card web 11 and runs over the fourth deflecting roller 22 before rejoining the card web 11 at the second gap-forming deflecting roller 19, for the card web 11 has in the meantime been transported by the upper carriage conveyor belt 20 into the gap between the first and second deflecting rollers 18 and 19 of the upper carriage 4. After leaving the gap, the card web 11 arrives on the upper strand 14 o of the laying carriage conveyor belt 14. On this belt, it is transported into the laying gap between the belts 14 and 23, which wrap around the laying rollers 12 and 13. On the way between the first deflecting roller 18 of the upper carriage 4 and the first laying roller 12 of the laying carriage 5, the card web 11 is accompanied on its top side by the lower strand 20 u of the upper carriage conveyor belt 20. After leaving the laying gap, the card web 11 arrives on the output conveyor belt 2.
During the operation of this embodiment of the inventive fleece layer, the laying carriage 5 moves back and forth between the edges of the output conveyor belt 2, which is indicated in the drawing by the double arrows X. When the laying carriage 5 moves toward the left out of the position at the right edge of the output conveyor belt 2 shown in the drawing, the upper carriage 4 moves also to the left at half the speed of the laying carriage 5 to accept the length of card web 11 being supplied by the movement of the web entrance conveyor belt 6, i.e., the length present in the section between the lower deflecting roller 9 of the web entrance and the first deflecting roller 18 on the upper carriage 4 and in the section between the first deflecting roller 18 and the first laying roller 12. When the laying gap reaches the left edge of the output conveyor belt 2, the directions of movement are reversed correspondingly.
While the laying carriage 5 is moving across the laid fleece, the lower strand 14 u of the laying carriage conveyor belt 14 is traveling in the direction of movement of the laying carriage 5 but at twice the speed of the laying carriage 5. To make it easier for the lower belt strand 14 u to slide over the laid fleece and to prevent the card which has been laid to form the fleece from being blown away, a slanted area is formed between the deflecting roller 15 of the laying carriage conveyor belt 14 and the lower guide roller of the belt spreader 16; this slanted area forms a tapering gap. When the laying carriage 5 is moving toward the left, the cover belt 23 simply lies on the laid fleece without relative velocity versus the fleece. The deflecting roller 24 of the cover belt 23 at the farthest point away from the second laying roller 13 is lowered as shown in the drawing, so that the full length of the lower strand of the cover belt 23 lies on the laid fleece. During movement in the opposite direction, however, the deflecting roller 24 is raised to make it easier for the belt to slide over the laid fleece and to prevent the fleece from being blown away.
It should be pointed out in this connection that, in simpler embodiments of the invention, especially when there is no need for fast laying speeds, the deflecting rollers 15 and 24 do not have to be height-adjustable. The deflecting rollers 15 and 24 can in this case remain in their raised position regardless of the direction of movement of the laying carriage 5.
At slow laying speeds, the cover belt 23 can also be made shorter than shown.
Drive rolls, deflecting pinions, and toothed belts are used to drive the various movable parts of the fleece layer shown. For example, the web entrance conveyor belt 6 is driven by a motorized deflecting roller 28, which is symbolized in the drawing by a circle with two black sectors. The upper carriage 4 is driven by a toothed belt 29, which is anchored to it and runs over a drive wheel 30 and a deflecting pinion 31, which are mounted in the machine stand 3. The laying carriage 5 is driven in a similar manner by a toothed belt 32, which runs over a drive wheel 33 and a deflecting pinion 34, which are mounted in the machine stand.
The drive of the upper carriage conveyor belt 20 is achieved by way of the web entrance conveyor belt 6, which wraps around the deflecting rollers 19 and 22, the second deflecting roller 19 being in toothed engagement with the adjacent first deflecting roller 18 of the upper carriage conveyor belt 20.
The laying carriage conveyor belt 14 and the cover belt 23 are driven by an endless toothed belt 35, which passes over deflecting pinions 36 supported in the machine stand and a drive pinion 37. This toothed belt 35 meshes with a toothed pinion 38, which is formed on one of the laying rollers 12, 13. The latter mesh with each other, so that they rotate in opposite directions.
The drives are controlled by a control unit (not shown) in correspondence with the laws prescribed for fleece layers, which are known and therefore do not need to be explained again here.
It should be remarked at this point that, in cases where it is possible not to cover the fleece on the output conveyor belt 2, such as in cases where the laying speeds are slow or the card webs are insensitive, the cover belt 23 in the laying carriage 5 can be eliminated. Its function at the laying gap will then be taken over by the remaining second laying roller 13.
It can be seen from the drawing that the invention completely eliminates the use of auxiliary carriages to keep the web conveyor belts under tension, which significantly reduces the complexity of the apparatus in comparison with the known sandwich-type fleece layers, which work with several carriages which are movable with respect to each other.

Claims

1. A fleece-laying apparatus of the carriage cross-lapper type, comprising:

a stationary web entrance;

an upper carriage and a laying carriage in each of which an endless conveyor belt travels; and

two laying rollers arranged in parallel at a same height in the laying carriage, the laying rollers forming 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 output conveyor belt, wherein

(a) a laying carriage conveyor belt wraps around the first laying roller, the upper and lower strands of the belt extending parallel to each other from the first laying roller,

(b) an endless cover belt which travels around in the laying carriage wraps around the second laying roller, the cover belt having upper and lower strands which extend parallel to each other from the second laying roller in the direction opposite that of the laying carriage conveyor belt, and

(c) the mutual distances between the web entrance, the upper carriage, the laying carriage, and the output conveyor belt in a direction perpendicular to the transport directions of same are so small that a first portion of the card web to be laid is enclosed in a sandwich-like manner between the adjacent strands of the web entrance conveyor belt and of the upper carriage conveyor belt, and a second portion of the card web to be laid is enclosed in a sandwich-like manner between the adjacent strands of the upper carriage conveyor belt and of the laying carriage conveyor belt, where the laid fleece on the output conveyor belt is contacted by the laying carriage conveyor belt and by the cover belt.

2. The fleece-laying apparatus according to claim 1 wherein, in the upper carriage, a second deflecting roller, around which the lower strand of the web entrance conveyor belt wraps, is closely adjacent to, and at the same height as, a first deflecting roller, which deflects the upper carriage conveyor belt.

3. The fleece-laying apparatus according to claim 2 wherein, in the upper carriage, a third deflecting roller is supported, around which the lower strand of the web entrance conveyor belt is guided to the second deflecting roller.

4. The fleece-laying apparatus according to claim 1 wherein:

in the area farthest away from the laying rollers, the laying carriage conveyor belt and the cover belt are each guided over a deflecting roller of a diameter smaller than that of the laying rollers;

a belt spreader is located between each of these deflecting rollers and the associated laying roller, each of these spreaders holding the sections of the upper and lower strands of the laying carriage conveyor belt and of the cover belt extending between it and the associated laying roller parallel to each other; and

said deflecting rollers are mounted at a first height such that the section of the upper strand of the belt in question extending between it and the belt spreader extends as a straight continuation of the adjacent belt section located between the belt spreader and the associated laying roller.

5. The fleece-laying apparatus according to claim 4 wherein the deflecting rollers of reduced diameter are each supported in a bracket, by means of which they can be moved individually from the first height to a second height, at which the section of the lower strand of the belt in question extending between the deflecting roller and the belt spreader extends as a straight continuation of the adjacent belt section located between the belt spreader and the associated laying roller.

6. The fleece-laying apparatus according to claim 5 wherein the brackets for the deflecting rollers of reduced diameter are designed in such a way that the first and second heights are stable end positions, between which unstable intermediate positions are present.

7. The fleece-laying apparatus according to claim 5 wherein laterally projecting drivers are formed on the deflecting rollers of reduced diameter or their brackets, and, in the machine stand, devices are provided which, when the laying carriage moves, shift the deflecting rollers to the first or second height position as a function of the direction in which the laying carriage moves.

8. The fleece-laying apparatus according to claim 4 wherein between each laying roller and its associated belt spreader, a belt support device is provided, which supports the upper strand of the belt in question from underneath.

9. The fleece-laying apparatus according to claim 1 wherein, in the upper carriage, a belt support device is provided, which supports the upper strand of the upper carriage conveyor belt from underneath.

10. The fleece-laying apparatus according to claim 2 wherein the first and second deflecting rollers in the upper carriage are in toothed engagement with each other.

11. The fleece-laying apparatus according claim 1 wherein the laying rollers are in toothed engagement with each other, and one of them is in engagement with a toothed belt, which is routed through the laying carriage and guided over and driven by deflecting and drive pinions supported in the machine stand.

12. The fleece-laying apparatus according to claim 1 wherein the upper carriage conveyor belt is air-permeable.