EP1532302B2 - Device and method for laying non-woven material - Google Patents

Abstract

The invention relates to a method and device for processing fibre material, whereby said device comprises at least one non-woven material laying device (3), to which a non-woven material web (8), formed from fibres, is supplied by a non-woven material generator. A drawing device for the non-woven material web (8) is arranged to the inlet side before the non-woven material laying device (3), whereby the variable speed of the non-woven material web generated therein is compensated for in an integrated buffer device (4) in the fleece laying device (3). The buffering occurs in a strip section (28) in the feed section of the upper carriage (11) and in the region between the upper carriage (11) and the laying carriage (12) of the non-woven material laying device (3).

Description

The invention relates to a device and a method for fiber treatment with the features in the preamble of the independent claims 1 and 12.

Such a device and such a method for fiber treatment are known from WO 99/24650 A known.

The DE-A 43 04 988 shows a nonwoven with an upstream input side stretching device in which the velocities of the florführenden drives the unwoven are lifted or lowered uniformly compared to the constant Florabgabegeschwindigkeit the upstream card. The nonwoven layer can also have an integrated pile memory.

From the DE 37 38 190 C2 and the DE 40 10 174 A1 For example, another type of distortion formation is known that takes place inside the leveler and in the area between its main body. Here, the driving speed of the laying carriage relative to the take-off belt is changed relative to the exit speed of the pile on the laying carriage. To compensate for the resulting differences in length in the belt loops one or more tensioning carriages may be present.

It is an object of the present invention to improve the known devices and methods for fiber treatment with regard to the delay options.

The invention solves this problem with the features of the independent claims 1 and 12.
By integrating the buffer device in the nonwoven layer, it is possible to compensate for the externally generated fluctuating Florlaufgeschwindigkeiten in nonwoven and while doing with the existing space and possibly with the existing machine technology of the web layer. Additional equipment and buffering devices in front of or behind the nonwoven layer can be dispensed with. This makes it possible to retrofit existing fiber treatment plants with minimal effort or rebuild and also to produce and operate new plants at low cost.

For the integrated buffering, an existing nonwoven layer can be used if it already has the necessary hardware. In this case, only the control for the affected thriving drives and the functions need to be changed and adapted. The design effort is minimal. Older nonwovens, which do not provide the necessary hardware requirements, can be exchanged for modernization of the fiber treatment plant against a new fleece laying with integrated buffer device while maintaining the existing construction and plant space.

The buffer device can be integrated into any types of non-wovens with at least two main carriages with conveyor belts and an inlet region with appropriate adaptation of their components and their kinematics. Particular advantages here are in so-called tape layers, in which the conveyor belts are guided in closed endless loops on both main cars and possibly also on auxiliary cars. Alternatively, the buffer technique can also be used in so-called. Wagenleger, in which the conveyor belts are each assigned to one of the main car and rotate only on this. For the formation of the buffer device in this case additional intermediate cars can be used. A integrated of the aforementioned type, buffer device is also possible with other types of nonwovens, eg camelbackers and the like.

The fleece layer upstream means for changing the Florlaufgeschwindigkeit and especially on the input side of the nonwoven laying pile infeed speed are delay devices in the form of stretching devices which have one or more stretch sections.

The buffer device integrated in the nonwoven layer makes it possible to deliver the nonwoven at the output side to the nonwoven layer at a substantially constant speed and to feed it to a downstream processing device, in particular a consolidation device or a needle machine. The release rate is in this case between minimum and maximum value of the fluctuating Florlaufgeschwindigkeiten on the input side of the batt.

The buffering or compensation of the variable Florlaufgeschwindigkeiten and resulting in drafting different pile lengths takes place within the batt in the area between the two main cars and this in the area of the superstructure and between the main car via a variable length band section, at least temporarily an excess length to accommodate the increased pile length having. In this case, the conveyor belts may have a correspondingly greater length than conventional nonwovens. To create the variable-length tape sections of the superstructure is decoupled from the laying carriage and takes to accommodate larger pile lengths longer distances than normal, where he also drives with a correspondingly changed speed. In this case, in spite of the internal buffer function, it is also possible to retain the previous functions of the fleece layer for edge thickness compensation. As a result, at the edge regions of the laying width of the laying carriage only those amounts of sheet are delivered and stored on the discharge belt, which correspond to his in this area on the braking and acceleration phases correspondingly reduced speeds.

In the subclaims further advantageous embodiments of the invention are given.

Figur 1:

eine Faserbehandlungsanlage mit einem Vliesleger mit integrierter Puffereinrichtung und weiteren Anlagenkomponenten in perspektivischer Darstellung,

Figur 2:

den Vliesleger von Figur 1 mit einer eingangsseitig vorgeschalteten Streckeinrichtung und einem Florerzeuger in abgebrochener Seitenansicht,

Figur 3:

eine Schemadarstellung eines Vlieslegers mit Haupt- und Hilfswagen und einer anderen Streckeinrichtung in Seitenansicht,

Figur 4:

eine Arisicht des Vlieslegers mit einer nachgeschalteten Nadelmaschine gemäß Pfeil IV von Figur 2,

Figur 5:

eine Diagramm-Darstellung der Fahrwege und Wendepunkte der beiden Hauptwagen bzgl. des Abzugsbandes und

Figur 6:

Geschwindigkeitsdiagramme für die Hauptwagen sowie Floreinlauf und Florauslauf.

The invention is illustrated by way of example and schematically in the drawings. In detail show:

FIG. 1:

a fiber treatment plant with a nonwoven layer with integrated buffer device and other plant components in a perspective view,

FIG. 2:

the fleece layer of FIG. 1 with an input side upstream stretching device and a pile generator in a broken side view,

FIG. 3:

a schematic representation of a fleece layer with main and auxiliary carriage and another stretching device in side view,

FIG. 4:

an Arisicht the nonwoven with a downstream needle machine according to arrow IV of FIG. 2 .

FIG. 5:

a diagram of the routes and turning points of the two main car with respect to the deduction band and

FIG. 6:

Speed diagrams for the main cars, as well as pile infeed and pile run.

Figure 1 to 3 show a fiber treatment plant (1) in different embodiments and views. The fiber treatment plant (1) consists in each case of at least one fleece layer (3) with an integrated buffer device (6). Furthermore, part of the fiber treatment plant (1) may be an upstream pile producer (2), in particular a card or carding machine. The pile producer (2) produces a pile consisting of loose fibers, preferably a single ply (8), which is fed to the fleece layer (3) via a pile feed (10). The nonwoven layer (3) deposits the pile (8) in a scaly manner into a multilayer nonwoven (9) on its exit side draw-off strip (17).

The fiber treatment plant (1) may also comprise one or more processing devices for the fleece (9) connected downstream of the nonwoven layer (3). In the embodiment shown, this is a solidification device (4) in the form of a needle machine. Alternatively, it may be a thermal or water jetting solidifying device. The nonwoven fabric (9) delivered by the draw-off belt (17) is fed to the solidification device (4) via its feed belt (18).

To the fiber treatment plant (1) may further include means (5) for changing the Florlaufgeschwindigkeit. This is a delay device for the pile (8). The device (5) is connected upstream of the nonwoven layer on the input side.

In FIG. 2 and 3 For this purpose, an embodiment in the form of a stretching device (5) for the pile is shown. In FIG. 2 the stretching device (5) on the input side of the nonwoven layer (3) immediately upstream and integrated in the housing. The normally usual infeed belt is hereby replaced by the stretching device (5). The stretching device (5) can in this case also be integrated into the inlet region (15) of the nonwoven layer (3). In the embodiment shown, the stretching device (5) has two or more consecutively arranged stretching sections (23, 24), on which the pile (8) is guided between pinch rolls (25) or between clamping strip sections (not shown). In order to stretch the pile (8) delivered by the carding machine (2) at a substantially constant speed, the pinch rolls (25) run in the drawing sections (23, 24) with increasing speed in sections, whereby the pile (8) is thinned and at the same time lengthened ,

FIG. 3 shows for this purpose a simpler variant of the stretching device (5), in which only two pairs of pinch rollers (25) are present, which may be distanced via a conveyor belt in the direction of flow direction (16). In this simplified embodiment, there is only one stretch section (22) between the pinch roller pairs (25) which defines a draft length or stretch length x. In the multi-level, more complex variant of FIG. 2 result in accordance with the number of stretch sections (23,24) several individual delay lengths that add up to a total delay length. For clarity, the default lengths are in FIG. 2 not shown.

The distortions formed in the pile (8) are deposited on the take-off belt (17) at the desired location after passing through the fleece layer (3). To ensure this, the location and time of the recovery are matched to the laying behavior of the fleece layer (3).

The stretching device (5) and in particular the drives M of the pinch rollers (25) and the clamping band sections are connected directly or indirectly to a controller (7) of the nonwoven layer (3). The stretching device (5) can in this case have its own control, which is connected via corresponding lines to the controller (7) of the nonwoven layer (3). Alternatively, the control of the stretching device (5) can be integrated in the controller (7) of the nonwoven layer in terms of hardware and / or software.

The changes in the Florlaufgeschwindigkeit produced by the drafting device (5) and the associated changes in the pile lengths are compensated in the nonwoven layer (3) described below in detail in the buffer device (6).

The nonwoven layer (3) is designed in the illustrated and preferred embodiments as a so-called. Band layer, its basic technique, for example, according to the WO 97/19209 is trained. It has two superimposed main cars (11,12), which are referred to as superstructure (11) and as laying carriage (12). In addition, the nonwoven layer (3) has two or more auxiliary carriages (13, 14) which are coupled to the movements of the main carriages (11, 12). The fleece layer (3) also has two conveyor belts (26, 27) guided in endless loops, both of which are guided via the two main carriages (11, 12) and also via the auxiliary carriages (13, 14). The main cars (11,12) move back and forth over the transverse take-off belt (17), wherein the laying carriage (12) panels and deposits the pile on the take-off belt (17) to the multilayer web (9). The travel lw of the laying carriage (12) is determined by the desired laying width. The superstructure (11) moves to a large extent in about half way and at half the speed of the laying carriage (12).

The main cars (11,12) are decoupled in their movements from each other and are controlled by independent drives (not shown) in their driving movements of the controller (7). The auxiliary carriages (13, 14) can be directly connected by means of connecting means, e.g. Cables, timing belts or the like. Be coupled to the movements of the associated main car (11,12) and move with these. Alternatively, the auxiliary carriages (13, 14) may also have their own drives (not shown) connected to the controller (7). Also, the conveyor belts (26,27) each have a drive (not shown) at a suitable location, which gives them a rotational speed and is also connected to the controller (7).

The buffer device (6) includes a modified controller (7) for generating buffer kinematics of the florführenden drives the main car (11,12) and the conveyor belts (26,27) and the trigger belt (17) and possibly also the independent drives of Auxiliary carriage (13,14). For buffering, the superstructure (11) carries out modified travel paths ow3, as described in the diagram of FIG FIG. 5 are shown and explained in detail. In addition, the conveyor belts (26,27) have a greater length than usual. Accordingly, the routes of the auxiliary carriage (13,14) can change. The laying carriage (12) retains its driving movement and driving distance lw above the draw-off belt (17) to form the fleece (9) with the respectively desired laying width.

In the embodiment of the stripper (3) shown, the conveyor belt (26) led out on the input side forms an inlet section (15) on which the infeed pile (8) is received on the input side and fed to the superstructure (11). On the superstructure (11), the second conveyor belt (27) is added, possibly with the formation of an inlet funnel, the two conveyor belts (26,27) then receive the pile (8) between them and lead on both sides to the laying carriage (12), where the Remove pile (8) again for storage on the draw-off belt (17).

The stripper (3) is in the preferred Embodiment, a so-called. Coordinated Leger, in which the two main cars (11,12) move in substantially the same direction, wherein the pile (8) in a band section directly from the upper carriage (11) to the laying carriage (12) is guided. In contrast, alternatively, the nonwoven layer (3) can also be designed as so-called. Opposing Leger, in which the conveyor belts between the uppercarriage (11) and laying carriage (12) are still guided over a stationary deflection in the frame of the nonwoven layer (3). In an opposite Leger move the main car (11,12) in substantially opposite directions. This variant is not shown for the sake of clarity.

For the in FIG. 2 and 3 shown co-rotating stripper (3) shows FIG. 3 the right card-side end position of the laying carriage (12) at the edge of the desired laying width, here for example on the right edge of the draw-off belt (17). This position is the so-called turning point at which the laying carriage (12) stops, changes its direction of travel and in moved back in the opposite direction. In FIG. 3 moves the laying carriage (12) from the inflection point back to the left on the discharge belt (17) in the direction of the arrow to the right back to the so-called rear.

FIG. 3 also shows the right cardinal end position and the turning point of the superstructure (11) with solid lines. The left rear end position of the upper carriage (11) is in FIG. 3 also shown and illustrated by a dashed line. FIG. 3 also shows the below explained maximum travel ow3 of the upper carriage (11). The lay carriage (12) is shown for clarity only in its right end position on the card side. The left end position on the rear side is not shown. In FIG. 3 instead, the travel lw of the laying carriage (12) to achieve the desired laying width of the fleece (9) on the draw-off belt (17) is shown.

To buffer the variable Florlaufgeschwindigkeiten and the variable pile lengths in a band section (28) in the feed region of the upper carriage (11) and in the area between the upper carriage (11) and laying carriage (12) are added. This also changes the rotational speed of the conveyor belt (26) in the inlet region (15), which corresponds essentially to the Floreinlaufgeschwindigkeit or the output speed of the drafting device (5). This local belt rotational speed is determined by the associated belt drive and the travel movements or drives of the two main cars (11,12) and possibly auxiliary carriage (13,14). In addition, the driving speed of the superstructure (11) is adjusted by the controller (7) corresponding to the variable Floreinlaufgeschwindigkeit, wherein the speed adjustment is transmitted simultaneously and directed to the superstructure (11).

In addition, the travel paths ow of the superstructure (11) change. The laying carriage (12) maintains its substantially uniform movement over the laying width and moves in the effective laying area at a substantially constant speed, which is between the minimum and maximum values of the fluctuating pile in speeds with respect to a round trip period. Like the speed diagrams of FIG. 6 For the pile infeed (15) and the laying carriage (12), the shaded areas (surface integrals above the respective speed) represent the amounts of fleece entering the fleece layer (3) at the pile infeed (15) and the laying carriage (12) on the drawstring (17). The Flormengen or Flächenintegrale must be the same during round-trip or period related, resulting in the function of the overall speed level of florführenden drives for the laying carriage (12) the required travel speed in the effective laying area, taking into account the most predetermined speed ramps in the brake and Acceleration phases Tu calculated at the turning points.

In the illustrated embodiments, the stretching device (5) for a targeted local dilution and extension of the pile (8), which is then stored after passing through the batt (3) at the desired location on the draw-off belt (7) to form the desired nonwoven profile. To accommodate the extended by the stretching pile lengths of the superstructure (11) performs an enlarged track ow3, in FIG. 5 is shown in more detail. In this case, an extension may take place on the way back and forth of the main car (11,12), but the upper carriage (11) preferably by a corresponding control action of the controller (7) only a piece on the rearward turning point on the normal path ow1 or ow2 moves out and has a one-way extended pathway ow3. On the card side, the position of the turning points in the driving paths ow1, ow2 and ow3 is substantially the same, with a lateral offset to the center of the laying width to ensure the necessary distance to the co-axial laying carriage (12).

Alternatively, especially in the case of increased laying and pile speeds, the cardinal inflection point can migrate in the direction of the rear side, with the rearward inflection point also correspondingly moving along. This requires an increased length of the nonwoven layer (3).

The normal travel path ow1 results when, with simple laying kinematics, the superstructure (11) always travels only half the path of the laying carriage (12) and moves in perfect sync with it. At both turning points of the laying carriage (12) then also the superstructure (11) stops. In this very simple kinematics edge thickening may arise at the edges of the laying area in the fleece (9), because in this laying kinematics of the pile (8) on the laying carriage (12) in the peripheral braking, stationary and acceleration phases despite reduced travel speed of the laying carriage with undiminished Speed escapes.

If the nonwoven layer (3) has a so-called edge thickness compensation, eg according to EP-A 0 517 563 or EP-A 0 522 893 The two main cars (11,12) are decoupled in their kinematics. The superstructure (11) then performs the both sides extended track ow2 according FIG. 5 out. Here, the superstructure (11) is in motion when the laying carriage (12) has reached its respective turning point. Here, the superstructure (11) receives the continuously fed pile in a correspondingly enlarged band section of the conveyor belts (26,27), the pile (8) on the laying carriage (12) only with a corresponding carriage carriage speed corresponding output speed and at the discharge belt ( 17) is stored. During the subsequent countermovement, the superstructure (11) moves at an increased speed relative to the laying carriage (12) and returns the temporarily stored pile (8), which is then deposited continuously by the laying carriage (12) on the draw-off belt (17). In a nonwoven layer (3) with edge thickness compensation, the in FIG. 5 track ow2 shown the normal route.

For buffering the variable Florlaufgeschwindigkeiten and at a stretching device (5) resulting variable pile lengths of the path ow3 of the upper carriage (11) is greater than the path ow2 in edge thickness compensation and is shifted on one or both sides. In this excess driving the enlarged pile length in the band sections (28) is cached and then accelerated while driving in the opposite direction from the superstructure (11) passed to the laying carriage (12) and deposited by this according to the desired nonwoven profile on the draw-off belt (17) ,

FIG. 6 illustrates the different speed ratios in speed diagrams. Here, the speed is plotted against time and with reference to a half period for the so-called outward journey from the card side to the rear side.

The uppermost diagram indicates the speed conditions at the pile infeed or on the conveyor belt (26) in the inlet region (15). Solid lines indicate in this case the speed which results when one or more distortions occur and in particular an extension of the pile at the stretching device (5). This extension is generated at the device (5) by temporary increase in speed, which adjusts in the same way or at least proportionally also at the inlet region (15) and the local belt speed. The normal distortion-free speed is represented by a dashed solid line. On the way from the card (2) facing side of the batt (3), the so-called card side, to the opposite rear side takes place, for example, a single stretch. This can be centered or eccentric to the laying width. Another connection can also take place on the way back, which is indicated in the further course of speed right from the rear inflection point.

Below the first diagram, the time T 1 is shown for the duration of the delay. On the edge side in the area of the turning points, the switching times Tu for braking and accelerating the carriage movements explained below up to the point of inflection and standstill are shown.

In the second diagram from above, the speeds of the upper carriage (11) are given. The dot-dash line indicates the speeds of the upper carriage (11) when it performs conventional driving movements synchronously with the laying carriage and has no compensation. This speed corresponds to the path ow1 of FIG. 5 , It can be seen here that the superstructure (11) has the same absolute absolute values of speed on the way there and back. The speeds are given direction-dependent, whereby the speed on the way to a positive sign and on the way back has a negative sign.

Dashed lines show the speed curve of the upper carriage (11) in the case of a compensation of edge thicknesses, which corresponds to the travel path ow2 of FIG. 5 corresponds. In comparison with the carriage movement indicated in the diagram below, it can be seen that the uppercarriage has its turning point and zero crossing of the speed earlier than the laying carriage in the area of the card-end inflection point. As a result, the superstructure is at rest of the laying carriage already back in motion and can record Flor for edge thickness compensation. At the rearward turning point the conditions are reversed, the uppercarriage (11) having its inflection point and zero crossing later than the laying carriage. As the diagram further illustrates, the speed of the upper carriage (11) on the way from the card to the rear side is lower than in the case of compensation-free travel. On the return path, however, the absolute value of the superstructure speed for edge thickness compensation is higher than without compensation.

In the superstructure diagram is shown by solid lines, the velocity profile in the internal buffering to compensate for variable Florlaufgeschwindigkeiten and distortion, in particular the example of stretching. The speed curve corresponds to the travel path ow3 of FIG. 5 , On the way out, the absolute value of the driving speed of the upper carriage (11) is lower than in the first two cases described above without compensation or with edge thickness compensation. Simultaneously with the extension and the speed increase in the pile inlet (15), an increase in speed also takes place in the superstructure (11). The absolute value of this speed change on the superstructure is not as great as in the Florlaufgeschwindigkeit, because here takes place an overlay with the also increased belt speed of the conveyor belt (26). On the return path is the absolute value of the driving speed of the upper carriage (11) at delay compensation (ow3) greater than in the two cases described above without compensation or with edge thickness compensation. If, on the way back, there is also a delay and, in particular, an extension, the absolute value of the superstructure speed for distortion compensation is reduced at the same time. If it is also intended to work with simultaneous edge compensation in the distortion compensation according to the invention, the superstructure (11) in this case has the same inflection points and zero crossings as in the above-described example of the pure edge thickness compensation.

According to the different lengths of travel ow1, ow2 and ow3 the superstructure (11) moves according to the diagram of FIG. 6 different speeds and different times. The longer the routes are ow1, ow2 and ow3, the longer the travel times are.

The third diagram shows the speed ratios for the laying carriage (12), the dashed line illustrating the laying carriage speed when compensating for edge thicknesses. Solid lines show the speed for the compensation of variable file speeds and warps. The third case of carriage carriage movement without compensation is illustrated by dotted lines. In all three cases, the laying carriage has the same turning point due to the laying width. On the way, the travel speed of the carriage (12) is the largest when compensating for delay (ow3). This also applies to the absolute value of the speed on the way back. The absolute speed level for edge thickness compensation (ow2) is lower. The absolute minimum speeds of the laying carriage (12) are the smallest, if no compensation takes place (ow1).

The lowest and last diagram of FIG. 6 shows speeds at the pile outlet of the laying carriage (12). This relates to the speed at which the pile (8) emerges from the laying carriage (12) and is deposited on the draw-off belt (17) to form the fleece (9). The line assignment for the three different motion and compensation cases are the same as in the above diagrams. If the nonwoven layer (3) does not perform any compensation, the pile outlet speed is constant, resulting in the above-described edge thickening. In the case of the compensation of edge thicknesses (ow 2), the web exit speed behaves synchronously with the travel speed of the carriage, including its braking and acceleration phases Tu. The speed level of the laying carriage Florauslaufs between the braking and acceleration phases is higher in the edge thickness compensation according to the increased laying carriage speed than in the above case without compensation. In the compensation of variable Florlaufgeschwindigkeiten and Verzügen the speed level of the Florauslaufs is even higher and also in sync with the speed behavior of the laying carriage (12). In both latter cases edge thicknesses are avoided.

As FIG. 4 illustrates, the nonwoven layer (3) on the discharge side to a downstream processing device, in particular a solidification device (4) is connected. This is a needle machine in the embodiment shown. The fleece (9) is transferred from the draw-off belt (17) to a feed belt (18) of the needle machine (4). The take-off belt (17) preferably carries out a conveying movement synchronous with the laying carriage (12). When the laying carriage (12) brakes in the peripheral areas, stops and accelerates again, the draw-off belt (17) moves accordingly in its transversely directed feed movement. On the other hand, the feed belt (18) can run continuously, the kinematic differences arising at the turning points of the laying carriage (12) being taken up at the transfer and the gusset between the draw-off belt (17) and the delivery belt (18).

The controller (21) of the needle machine (4) is connected to the controller (7) of the web laying machine (3) and receives from this a conductance for the speed of the drive (20) of the conveyor belt (18).

Modifications of the embodiments shown are possible in various ways. On the one hand, this relates to the technical basic form of the fleece layers (3), which can also be designed in the above-mentioned manner as opposing stripers, as a feeder or in any other suitable manner. Modifications, the hardening device (4) or needle machine is also accessible.

LIST OF REFERENCE NUMBERS

1

Fiber treatment plant

2

Pile fabric, card, card

3

lapper

4

Hardening device, needle machine

5

Drafting device, stretching device

6

buffer means

7

control

8th

pile

9

fleece

10

Florzuführung

11

first main car, superstructure

12

second main car, laying carriage

13

first auxiliary carriage

14

second auxiliary carriage

15

intake area

16

Running direction of pile or fleece

17

off belt

18

infeed

19

Drive trigger belt

20

Drive feed belt

21

Control needle machine

22

expanded section

23

expanded section

24

expanded section

25

pinch rolls

26

conveyor belt

27

conveyor belt

28

band section

M

drive

x

Warpage length, stretch length

lw

Track laying carriage

ow1

Track superstructure without compensation

OW2

Track superstructure with compensation edge thicknesses

OW3

Track superstructure with buffering delay

Claims (14)

1. Device for fibre treatment, with at least one nonwoven laying machine (3), to which a web (8) formed from fibres is supplied by a web producer (2), the nonwoven laying machine (3) being preceded by on the inlet side a means (5) for varying the web running speed, namely a drafting means for the web (8), and the nonwoven laying machine (3) having at least two main carriages (11, 12) with conveyor belts (26, 27) and with an entry region (15) and an integrated buffer means (6) for the fluctuating web running speeds, the travelling movements of the main carriages (11, 12) being decoupled, the upper carriage (11) executing an increased travel ow3 for buffering, characterized in that the drafting means (5) is designed as a drawing means with one or more drawing sections (22, 23, 24) which have nipping pairs of rollers (25) or band portions.
2. Device according to Claim 1, characterized in that the upper carriage (11) moves at a variable travelling speed which is essentially proportional to the fluctuating web running speed.
3. Device according to Claim 1 or 2, characterized in that the conveyor belt (26) located at the entry region (15) and entering at the upper carriage (11) moves at a variable speed which is essentially proportional to the fluctuating web running speed.
4. Device according to Claim 1, 2 or 3, characterized in that the laying carriage (12) moves, in the laying region, essentially at a constant travelling speed between the edge-side braking and accelerating phases Tu.
5. Device according to Claim 4, characterized in that the travelling speed of the laying carriage (12) is determined by the variable web lengths and lies between the minimum and the maximum value of the fluctuating web running speed.
6. Device according to one of the preceding claims, characterized in that the nonwoven laying machine (3) is designed as a band-type laying machine, in which the two conveyor belts (26, 27) are guided in an endless loop and via both main carriages (11, 12).
7. Device according to one of the preceding claims, characterized in that the nonwoven laying machine (3) has one or more auxiliary carriages (13, 14) for the conveyor belts (26, 27).
8. Device according to one of the preceding claims, characterized in that the nonwoven laying machine (3) is designed as a synchronous laying machine, the two main carriages (11, 12) moving codirectionally.
9. Device according to one of the preceding claims, characterized in that a band portion (28) of variable length, with an overlength for buffering the web (8), is formed in the nonwoven laying machine (3) by the conveyor belts (26, 27) in the region of the upper carriage (11) and between the main carriages (11, 12).
10. Device according to one of the preceding claims, characterized in that the nonwoven laying machine (3) has a control (7) for the drives of the conveyor belts (26, 27) and of the main carriages (11, 12), the preceding drafting means (5) being connected to this control (7).
11. Device according to one of the preceding claims, characterized in that the drafting means (5) is arranged between the nonwoven laying machine (3) and a preceding web producer.
12. Method for fibre treatment, with at least one nonwoven laying machine (3) which has at least two main carriages (11, 12) with conveyor belts (26, 27) and with an entry region (15), to which a web (8) formed from fibres is supplied by a web producer (2), the nonwoven laying machine (3) being preceded by on the inlet side a means (5) for varying the web running speed, namely a drafting means for the web (8), the fluctuating web running speeds being compensated in an integrated buffer means (6) of the nonwoven laying machine (3), wherein, for buffering, the variable web running speeds and the variable web lengths are absorbed in a band portion (28) in the supply region of the upper carriage (11) and in the region between the upper carriage (11) and laying carriage (12), the travelling movements of the main carriages (11, 12) being decoupled, the upper carriage (11) executing an increased travel ow3 for buffering, characterized in that the drafting means (5) is designed as a drawing means with one or more drawing sections (22, 23, 24) which have nipping pairs of rollers (25) or band portions.
13. Method according to Claim 12, characterized in that the upper carriage (11) is moved at a variable travelling speed which is essentially proportional to the fluctuating web running speed.
14. Method according to Claim 12 or 13, characterized in that the conveyor belt (26) located at the entry region (15) and entering at the upper carriage (11) moves at a variable speed which is essentially proportional to the fluctuating web running speed.

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