EP2169095A1 - Device for laying a fibre web evenly - Google Patents

Abstract

A plant for evenly laying a non-woven (17), formed from gauze sheet (16), having a laying device (15) with a laying carriage and conveyor belts (21) for guiding the gauze sheet into a delivery gap on the carriage, includes gauze edge adjusting device(s) (30), integrated into or upstream of the laying device, for altering the gauze width profile based on stored permitted values or width profile values determined by sensor(s) (32). A plant for evenly laying a non-woven (17), formed from gauze sheet (16), has (a) a non-woven laying device (15) with a laying carriage movable transverse to and above a take-off conveyor belt (1) and (b) at least two gauze conveyor belts (21) for guiding the gauze sheet into a delivery gap formed on the laying carriage. The novel feature is that the plant also has gauze edge adjusting device(s) (30), integrated into or upstream of the laying device, for altering the width profile of the gauze sheet based on (i) permitted values for the specific laying procedure, stored in a memory, or (ii) width profile values determined by sensor(s) (32) located in or downstream of the laying device. An independent claim is included for a corresponding non-woven laying method, including providing a non-woven laying device (17) with a laying carriage and gauze conveyor belts (21) as above, in which controlled adjustment of the gauze sheet edges is carried out upstream of or within the laying device, based on (i) ruling magnitudes for the specific laying procedure, stored in a memory, or (ii) width profile values determined by sensor(s) (32) located in or downstream of the laying device.

Description

The invention relates to a system for the uniform laying of a fleece, with which a card web is deposited on a delivery conveyor belt to a nonwoven.

Such systems have long been known and have a nonwoven, in which a laying carriage on a delivery conveyor belt for the laid nonwoven back and forth. At least two pile conveyor belts are used for transporting the card web to the depositing gap in the laying carriage, wherein the card web is at least partially sandwiched between two sections of the two conveyer belts. As a result, a secure guidance of the card web is guaranteed to Ableggespalt in the laying carriage. Due to the back and forth movement of the laying carriage and the forward movement of the delivery conveyor belt results on the delivery conveyor belt a multi-layer fleece with obliquely paneled pile layers. Examples of nonwovens with a superstructure and a laying carriage are from the US 4,830,351 and the EP 0 522 893 A known. A particularly embodied embodiment of a nonwoven layer is known from EP 1 816 243 A1 known.

To produce a uniform surface mass profile of the laid fleece, it is important to compensate for the lower speeds of the laying carriage in the region of its reversal points, so that edge thickening of the laid fleece are avoided. This is achieved by suitable control of the individual drives of the web laying with the aid of a built-in fleece laying memory or by a pre-compensation means of controlled changing the surface mass distribution of the card web to be laid, for example, by a cyclical, short-term stretching of the card web in the web laying or in an upstream drafting.

Frequently, however, not only in the transverse profile of the laid fleece, but also in the longitudinal profile unevenness arise. A major reason for this is the increase in the width of the card web as it passes through the batt, which is due, inter alia, to delays in the deflection of the card web, to the pressure exerted by the nap rolls on the card web, and also to aerodynamic effects arising during the ride of the web Change the superstructure and the laying carriage. In this respect, the Florbreitenzunahme is rarely constant, but there are often curved Florbahnränder, which lead to the filing of the card web in the paneled fleece that no precise layer closure of a fleece-laid pile webs is guaranteed on the laying width, ie the front edge of the uppermost pile layer does not directly connect to the rear edge of the bottommost pile layer. This results in - usually cyclic - surface mass fluctuations in the longitudinal profile of the laid fleece.

The present invention is therefore an object of the invention to provide a system for the uniform laying of a fleece, in which the layer closure of the laid card webs is guaranteed and the laid fleece thus also in the longitudinal direction has an even more uniform surface mass profile, and a corresponding method for uniform laying to specify a fleece.

This object is solved by the features of claim 1 or claim 9.

According to the invention, the system for the uniform laying of a nonwoven fabric from a card web has a nonwoven layering machine with a crosswise transport conveyor belt above the same movable laying carriage and at least two pile conveyor belts for guiding the card web into a delivery gap formed on the laying carriage. In addition, the system has at least one device for changing the Florbahnränder, which is integrated in the nonwoven or upstream of the crosslapper and is suitable, the width profile of the card web based on stored in a memory laws of specific laying operation or on the basis of at least one in or to change the actual values of the width profile of the card web detected behind the nonwoven layer. Thus, it is possible to vorzukompensieren the width of the card web at their edges according to the particular application and the various boundary conditions in a controlled manner such that the laid webs to the web have after passing through the nonwoven laying even edges.

The sensor can be arranged in the region of a superstructure. At this point, an intermediate observation can take place in most cases, since the edges of the card web have partially widened up to this point due to the drive of the upper carriage again.

Additionally or alternatively, a sensor may be arranged in the region of the laying carriage. Since the card web is placed directly on the delivery conveyor belt from the carriage, a measurement of the width of the card web at this point corresponds almost completely the actual width of the actually laid card web on the delivery conveyor. In this respect, a measurement at this point can guarantee a particularly accurate Florbreitenregelung.

A particularly easily controllable and flexible change of the Florbahnränder is possible in that preferably a suction device is used.

When using two suction nozzles, which are movable transversely to the conveying direction of the card web in the nonwoven, both edges of the card web can be adjusted independently and easily.

A simple and fast measurement is obtained when the sensor is a radiometric or optical sensor.

• Bereitstellen eines Vlieslegers mit einem quer zu einem Abliefertransportband oberhalb desselben beweglichen Legewagen sowie zwei Flortransportbändern zur Führung der Florbahn in einen am Legewagen ausgebildeten Abgabespalt, und
• gesteuertes Verändern der Florbahnränder vor dem oder im Vliesleger zur Anpassung des Breitenprofils der Florbahn auf Basis von in einem Speicher hinterlegten Gesetzmäßigkeiten des spezifischen Legevorgangs oder auf Basis von durch mindestens einen im oder hinter dem Vliesleger angeordneten Sensor erfassten Ist-Werten des Breitenprofils der Florbahn.

The method according to the invention for the uniform laying of a nonwoven fabric from a card web has the following steps:

• Providing a batt with a transversely to a delivery conveyor belt above the same movable carriage and two Flortransportbändern for guiding the card web in a laying carriage formed on the discharge gap, and
• controlled changing of the Florbahnränder before or in the nonwoven for adjusting the width profile of the card web based on stored in a memory laws of specific laying operation or on the basis of at least one arranged in or behind the nonwoven laid sensor actual values of the width profile of the card web.

By this method, the uniformity of the laid nonwoven fabric can be ensured in the longitudinal direction in a particularly simple and accurate manner.

Since the regularities of the change of the width profile of the card web, which occurs in the nonwoven in the passage of the card web, depends on a variety of factors, it is advantageous to perform previously in a test operation recording the laws. In this case, the influences of the throughput speed of the card web by the nonwoven layer, the individual distortions due to mechanical settings, the fiber orientation in the pile, the fiber fineness and area weight distribution of the card web to the width change of the card web for the specific application can be determined exactly.

It is preferred that the two edges of the card web be sucked controlled by means of two suction nozzles in order to change the width profile of the card web. In this case, the two suction nozzles are preferably transversely movable to the conveying direction of the card web in the nonwoven, whereby the accuracy of the suction is further increased.

By a separate control of the two suction nozzles and a non-symmetrical pre-compensation of the two edges of the card web can be made in order to be able to respond to specific peculiarities of the mechanical devices in the nonwoven fabric in more detail.

Fig. 1

ist eine schematische Ansicht einer Ausführungsform der erfindungsgemäßen Anlage zum Legen eines Vlieses, und

Fig. 2

ist eine schematische Draufsicht auf die für die Erfindung wesentlichen Teile der Anlage aus Fig. 1.

Further details and advantages of the present invention will become apparent from the following description with reference to the drawings.

Fig. 1

is a schematic view of an embodiment of the plant according to the invention for laying a fleece, and

Fig. 2

is a schematic plan view of the essential for the invention parts of the system Fig. 1 ,

Fig. 1 shows a schematic view of a first embodiment of the invention in a front view with respect to a delivery conveyor belt. One recognizes in Fig. 1 a nonwoven 15 with an endless circulating delivery conveyor belt 1, which is intended to a laid fleece 17 (see Fig. 2 ) in a transport direction perpendicular to the plane of transport. From guide devices of the delivery conveyor belt 1, an upper guide roller 2 is shown. About the delivery conveyor belt 1, a laying carriage 3 on rails or tubes 3a is moved back and forth. In the laying carriage 3, two guide rollers 4 and 5 are freely rotatably mounted. The first guide roller 4 is partially wrapped by a cover strip 6, which has a lower strand, which runs at a close distance above the delivery conveyor belt 1 to a driven guide roller 7, via a further stationary guide roller 8 and to a guide roller 9, in a first tensioning carriage 10th is rotatably mounted, which is movable transversely to this on rails or tubes 10a below the delivery conveyor belt 1. Of the mounted in the tensioning carriage 10 guide roller 9 said cover strip 6 extends over two further stationary guide rollers 7a and 8a back to the laying carriage 3. The driven guide roller 7 is is coupled to a motor (not shown) and is intended to drive the masking tape 6.

Similarly, the other guide roller 5, which is rotatably mounted in the laying carriage 3, partially wrapped by a Flortransportband 11, which is called in another second Flortransportband 11, via a driven guide roller 12 and a stationary guide roller 13 to one in the first tensioning carriage 10th mounted second deflecting roller 14 is guided, which is partially wrapped by the pile conveyor belt 11, from where the pile conveyor belt 11 via further stationary guide rollers 12a and 13a to the laying carriage 3 runs back. The second pile conveyor belt 11 has a lower run, which runs at a close distance above the delivery conveyor belt 1 and also performs the function of a cover strip for the laid nonwoven 17. The driven deflection roller 12 is coupled to a motor (not shown) and is intended to drive the second pile conveyor belt 11.

At the carriage 3, a chain or a toothed belt is mounted, which runs for example via a drive gear connected to a motor and a deflection wheel (all elements not shown). With the aid of these drive devices, the laying carriage 3 can be moved back and forth across the delivery conveyor belt 1 transversely to its transport direction.

Essentially at one level with the laying carriage 3, an upper carriage 18 is mounted so as to be movable transversely to the transport direction of the delivery conveyor belt 1 on rails or tubes 3a in the machine frame of the fleece layer 15. The rails or tubes 3a may be the same rails or tubes on which the laying carriage 3 is mounted movable. The uppercarriage 18 has an upper guide roller 19 and a lower guide roller 20, which are laterally offset from each other. About these two guide rollers 19 and 20 runs another Flortransportband 21, which is subsequently called first Flortransportband 21. In the area bounded by the two guide rollers 19 and 20 in the uppercarriage 18, the first pile conveyor belt 21 is inclined obliquely downwards. Starting from the lower deflection roller 20 in the uppercarriage 18, the first Flortransportband 21 runs parallel to the upper strand of the second Flortransportbandes 11. The first Flortransportband 21 is after the laying carriage 3 via a stationary mounted, motor-driven guide roller 25 and from there via a in a second clamping carriage 23rd mounted deflecting roller 24 out, and then several stationary in the machine frame mounted (hereinafter "stationary") Deflection rollers 22 to run before it reaches the superstructure 18 again. The O bogie 18 and the second tensioning carriage 23 are connected to each other via a chain or a toothed belt (not shown), which via a motor (not shown) connected to the drive gear and a deflection wheel, which are mounted in the machine frame, running (not shown ). The clamping carriage 23 is also movably mounted on rails or tubes 23a. Furthermore one recognizes in Fig. 1 an obliquely upwardly extending feed belt 29, which is to be laid a card web 16 (see Fig. 2 ) feeds the first pile conveyor belt 21.

In the area between the lower deflecting roller 20 of the upper carriage 18 and the second deflecting roller 5 of the laying carriage 3, portions of the first pile transport belt 21 and the second pile transport belt 11 are guided parallel to one another in close proximity, so that a card web 16 guided from the first web transport belt 21 in said Area between the uppercarriage 18 and the laying carriage 3 from the first pile conveyor belt 21 and the second pile conveyor belt 11 is sandwiched. In this case, the card web 16 is supported by the second pile conveyor belt 11. As already mentioned, the lower strand of this second pile conveyor belt 11 simultaneously also assumes the function of a cover strip for the laid nonwoven fabric 17.

It can be seen in the drawing that in operation, when the laying carriage 3 executes a reciprocating over the delivery conveyor belt 1 movement, the first tensioning carriage 10 performs an opposite movement, because the loop lengths of the cover strip 6 and the second pile conveyor belt 11 are constant. Furthermore, the uppercarriage 18 and its associated second tensioning carriage 23 perform a mutually opposite motion during operation, because they are positively connected with each other. The second tensioning carriage 23 is necessary to keep the loop length of the first pile conveyor belt 21 constant.

The movements of laying carriage 3 and upper carriage 18 are coordinated so that when feeding the card web 16 via the feed belt 29 at a uniform speed controlled storage of the card web 16 without stretching or compression within the illustrated web layer 15 can take place on the delivery conveyor belt 1. In this case, the superstructure 18 moves in each case in the same direction, on average only half as fast as the laying carriage 3. It is also taken into account that the laying carriage 3 in the region of its movement reversal position must be decelerated to a stop and accelerated again. If the card web 16 with fluctuating speed fed, for example, because before the feed belt 29, a cyclically operating drafting arrangement (not shown) is arranged, which generates an alternating thickness in the card web 16 for the purpose of achieving a cross-profiling of the laid web, can by means of an independent control of the movement of superstructure 18th and laying carriage 3 in a known manner a Florbahnpufferung be made within the web layer 15.

The masking tape 6 and the web conveyor belt 11 form at the point where they are deflected in the laying carriage 3 of their guide rollers 4 and 5, a gap which is initially referred to as a discharge gap. During operation of the fleece layer 15, the second pile conveyor belt 11 is driven so that its upper run follows the movement of the lower run of the first pile conveyor belt 21 because both belts enclose the pile web 16 between the upper carriage 18 and the laying carriage 3 between them.

According to this embodiment, a total of three bands are included in the nonwoven 15. However, the invention can also be applied to all other nonwoven layers, i.a. those with two bands, apply. The invention is also applicable to opposite Leger, in which the upper carriage 18 and the carriage 3 move in opposite directions, or on Steilarmvliesleger.

How out Fig. 1 As can be seen, a device 30 for changing the pile web edges is now arranged in the entrance area of the fleece layer 15. In the present specific embodiment, the Fig. 2 can be seen even better, the device 30 for changing the Florbahnränder from a suction device having two suction nozzles in the region of the two edges of the card web 16. These suction nozzles 30 are movable transversely to the transport direction of the card web 16 in the crosslapper 15 in the preferred example and can adapt by targeted suction, the edges of the card web 16 and thus give their width profile a predetermined contour.

The control of the device 30 for changing the Florbahnränder carried out in a first embodiment based on stored in a memory laws of the specific laying process. In this case, preferably all parameters which have an influence on the width change of the card web 16 are taken into account. As parameters are, for example, the passage speed of the card web 16 through the nonwoven layer 15, the laying width of the web layer 15, the distortions of the card web 16 due to mechanical settings, to name the fiber orientation in the card web 16, the fiber denier and the basis weight distribution of the card web 16.

If necessary, a test can be run in advance in order to be able to determine the exact course of change of the width profile of the card web 16 during the laying process.

The predicted widenings of the card web 16 at certain points in its passage through the nonwoven layer 15 are therefore to be compensated by a precompensation, i. a width reduction, be compensated by means of the device 30 for changing the Florbahnränder. In this case, the card web 16 receives a certain contour in its width profile.

In order to be able to check the result, several sensors 32 are arranged in the fleece layer 15, which check the edges and the width of the card web 16. Preferably, the sensors 32 are radiometric or optical sensors, but for example also infrared, laser, ultrasonic sensors or sensors for radioactive radiation come into question. It can also be provided only a sensor 32.

In the illustrated example case two sensors 32 in the region of the upper carriage 18 and two sensors 32 in the region of the laying carriage 3 are arranged in each case. The two arranged in the region of the laying carriage 3 sensors 32 for the left and the right edge of the card web 16 are particularly useful because they check immediately before dropping the card web 16, the edges and the width of the card web 16 and thus accurate conclusions on the on allowed the Abelfertransportband 1 Flordahnlagen and the uniformity of the edges allowed.

In a particularly preferred embodiment, the results of the sensor 32 and the sensors 32 are used in a control loop to control the device 30 for changing the Florbahnränder. This results in a self-regulating system that ensures a particularly high uniformity of the laid web 17.

In this case, it is also particularly advantageous if both suction nozzles 30 can be controlled separately from one another, since then the two edges of the card web 16 can be processed independently of each other and thus unbalanced pile widening in the nonwoven layer 15 can be compensated.

In the illustrated example, the device 30 for changing the Florbahnränder is integrated in the input region of the web layer 15. However, it can also be arranged shortly before the superstructure 18 or lie in front of the nonwoven layer 15. The sensors 32 are not limited to the positions shown. Thus, it is possible, for example, even after the delivery of the card web 16 by the laying carriage 3 to provide a sensor 32 which checks the deposited on the delivery conveyor belt 1 webs 16 and the edges thereof. Finally, the invention is not limited to the use of suction nozzles as a device 30 for changing the Florbahnränder. Alternatively, any other device suitable for controlled variation of the web width can be used. For example, a reduction in the width of the card web 16 could also be produced by longitudinal stretching of the card web 16 in a drafting system. In this case, however, the thickness change produced in the longitudinal profile of the card web 16 in the activation of the drives of the web layer 15 would have to be considered.

Claims (14)

Plant for uniformly laying a fleece (17) from a card web (16) comprising a fleece layer (15) with a transversely to a delivery conveyor belt (1) above the same movable laying carriage (3) and at least two pile conveyor belts (11, 21) for guiding the Florbahn (16) in a laying carriage (3) formed discharge gap,
characterized in that
the system also has at least one device (30) for changing the pile edges, which is integrated into the nonwoven layer (15) or upstream of the nonwoven layer (15) and is suitable for the width profile of the card web (16) on the basis of regularities stored in a memory the specific laying operation or on the basis of at least one in or behind the nonwoven layer (15) arranged sensor (32) detected actual values of the width profile of the card web (16) to change. Installation according to claim 1, characterized in that at least one sensor (32) in the region of the upper carriage (18) is arranged. Installation according to claim 1 or 2, characterized in that at least one sensor (32) in the region of the laying carriage (3) is arranged. Installation according to one of the preceding claims, characterized in that the device (30) is designed to change the Florbahnränder as a suction device. Installation according to claim 4, characterized in that the device (30) for changing the Florbahnränder two suction nozzles, which are transverse to the conveying direction of the card web (16) in the nonwoven layer (15) movable. Installation according to claim 5, characterized in that the nonwoven layer (15) is designed as a co-casual layer. Installation according to one of the preceding claims, characterized in that the first pile conveyor belt (21) on the superstructure (18) forms a belt inlet with an obliquely downwardly inclined inlet section and also by the laying carriage (3) through to the superstructure (18) is returned, and that the second pile conveyor belt (11) is guided through the laying carriage (3) and a tensioning carriage (10) movable transversely to the delivery conveyor belt (1), but not also through the superstructure (18). Installation according to one of the preceding claims, characterized in that the sensor (32) is a radiometric or optical sensor. Method for uniformly laying a fleece (17) out of a card web (16), comprising the following steps: Providing a fleece layer (15) with a transversely to a delivery conveyor belt (1) above the same movable laying carriage (3) and at least two pile conveyor belts (11, 21) for guiding the card web in a discharge gap formed on the laying carriage (3),
marked by - controlled varying the Florbahnränder before or in the crosslapper (15) for adjustment of the width profile of the card web (16) based on stored in a memory laws of the specific laying operation or on the basis of spaced by at least one in or downstream of the crosslapper (15) sensor (32) detected actual values of the width profile of the card web (16). A method according to claim 9, characterized in that previously in a test operation, a recording of the laws is performed. A method according to claim 9 or 10, characterized in that the two edges of the card web (16) are sucked controlled by means of two suction nozzles (30) to change the width profile of the card web (16). A method according to claim 11, characterized in that the two suction nozzles (30) are moved transversely to the conveying direction of the card web (16) in the nonwoven layer (15). A method according to claim 12, characterized in that the two suction nozzles (30) are driven separately. Method according to one of claims 9 to 13, characterized in that the measurement is carried out by the at least one sensor (32) in the region of the laying carriage.

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