EP3450604B1 - Method for forming a profiled, solidified nonwoven fabric product - Google Patents

Description

The present invention relates to a method of forming a profiled, bonded nonwoven product.

In certain nonwoven applications, it may be desirable to produce a nonwoven product having a predetermined non-uniform transverse and/or longitudinal profile. An example of application is the production of elements for the interior lining of motor vehicles.

To produce a profiled, consolidated nonwoven product, for example, in EP 2 695 976 A1 describes a feed device for feeding dissolved fibers onto a transport device which has a plurality of feed segments arranged horizontally next to one another. A separately controllable feed roller is assigned to each feed segment, which draws in the respective fiber base material, which is then broken up into individual fibers or fiber tufts by means of an opening roller and sprinkled onto the transport device. In this way, a profiled fleece web can be produced by different activation of the feed rollers in the feed segments, which web can then be subjected to a strengthening process, for example by needling.

It has been found that with this type of profile-forming unit, there is no particularly intimate connection by fiber bridges in the transverse direction of the fleece produced, so that ultimately inhomogeneities and deviations from the desired fiber mass distribution can arise. In addition, the transitions between the fiber accumulations scattered by two feed segments arranged next to one another can in some cases be relatively erratic, which still exist after solidification.

U.S. 2007/298667 A1 describes a process for making a nonwoven liquid absorbing product such as a diaper. In this case, an already solidified fiber fleece is first placed on a net-like base. Then, by applying a jet of heated gas to the non-woven fabric in a targeted manner, fibers are loosened in certain areas in order to form groove sections in the non-woven fabric. The solidification of the groove portions is accomplished by cooling the heated fibers. An upper cover layer is in turn applied to the consolidated nonwoven fabric.

EP 2 644 761 A1 describes a process for forming a profiled lofty nonwoven web for making a cleaning sheet. Here, a fiber fleece is first dissolved by high-pressure water jets. The opened batt is then placed against a forming plate formed from elongate spaced elements. With the aid of high-pressure water jets, the dissolved nonwoven is then pressed into the areas between the spaced elements of the forming plate, resulting in a dissolved nonwoven with grooved sections. The loosened fiber fleece is dried with the help of a jet of hot air. Finally, the cleaning cloth is solidified by cooling the non-woven fabric.

The present invention is based on the object of specifying a method for forming a profiled, consolidated nonwoven product with which a nonwoven product with a high level of stability is ensured both in the longitudinal and transverse directions of the nonwoven product and with which smooth transitions between areas of the produced solidified web product can be achieved.

• Bilden einer profilierten Faseransammlung oder eines profilierten Vlies-Zwischenprodukts, das eine profilierte Faseransammlung ist;
• Zuführen und Ablegen eines Abdeckvlieses von oben auf die profilierte Faseransammlung zum Bilden eines profilierten Vlieses und Verfestigen des profilierten Vlieses in einer Verfestigungsvorrichtung zur Bildung des profilierten, verfestigten Vliesprodukts bzw. Zuführen und Ablegen eines Abdeckvlieses von oben auf das profilierte Vlies-Zwischenprodukt zum Bilden eines profilierten Vlieses und Verfestigen des profilierten Vlieses in einer Verfestigungsvorrichtung zur Bildung des profilierten, verfestigten Vliesprodukts; wobei zum Bilden des profilierten Vlieses ein Grundvlies zugeführt wird, auf dem die profilierte Faseransammlung oder das Vlies-Zwischenprodukt abgelegt wird, sodass das profilierte Vlies ein Sandwich aus Grundvlies, profilierter Faseransammlung bzw. Vlies-Zwischenprodukt und Abdeckvlies aufweist, und
• wobei die profilierte Faseransammlung durch eine Zuführvorrichtung mit mehreren horizontal nebeneinander angeordneten Zuführsegmenten gebildet wird bzw. das profilierte Vlies-Zwischenprodukt durch eine Zuführvorrichtung mit mehreren horizontal nebeneinander angeordneten Zuführsegmenten gebildet wird.

According to the invention, the method for forming a profiled, consolidated nonwoven product comprises the following steps:

• forming a profiled fiber aggregate or a profiled nonwoven intermediate that is a profiled fiber aggregate;
• Feeding and depositing a cover fleece from above onto the profiled fiber accumulation to form a profiled fleece and consolidating the profiled fleece in a consolidation device to form the profiled, consolidated fleece product or feeding and depositing a cover fleece from above onto the profiled fleece intermediate product to form a profiled mat and consolidating the profiled mat in a consolidating device to form the profiled, consolidated mat product; wherein a base web is fed to form the profiled web, on which the profiled fiber aggregate or web intermediate is deposited, so that the profiled web has a sandwich of base web, profiled fiber aggregate or web intermediate and cover web, and
• wherein the profiled fiber accumulation is formed by a feed device with a plurality of feed segments arranged horizontally next to one another or the profiled nonwoven intermediate product is formed by a feed device with a plurality of feed segments arranged horizontally next to one another.

A basic strength is added to the profiled fiber accumulation by the feeding of the covering fleece. In addition, possible abrupt transitions between fiber mass sections of different heights of the profile are already softened by the covering fleece before the solidification. Finally, the cover fleece also provides the advantage of preventing fibers from being blown out of the profiled fiber accumulation.

To form the profiled mat, a base mat is also fed, on which the profiled fiber accumulation is laid, so that the profiled mat has a sandwich of base mat, profiled fiber accumulation and cover mat, or on which the profiled mat intermediate product is laid, so that the profiled mat a Having a sandwich of base fleece, profiled fleece intermediate product and cover fleece. This further increases the basic strength of the profiled fleece and the profiled fiber accumulation or the profiled fleece intermediate product is optimally protected against blowing in the sandwich layer.

The profiled fiber aggregate is preferably formed by previously forming a profiled mat intermediate and opening the mat intermediate in an opening unit. In this way, intimate fiber bridges are generated in all directions in the profiled fiber accumulation.

The opening unit preferably has at least one opening roller provided with teeth or pins, which scatters the opened fibers or fiber tufts of the fleece intermediate product as a profiled accumulation of fibers onto the base fleece or onto a conveying device.

Such an opening roller preferably has a speed of at least 200 revolutions/min, preferably at least 500 revolutions/min, preferably at least 1000 revolutions/min, more preferably at least 2000 revolutions/min, even more preferably at least 3000 revolutions/min. This ensures complete dissolution of the nonwoven intermediate product into individual fibers or fiber flocks.

In order to increase the stability of the profiled fiber accumulation during scattering or transport on the conveying device, the conveying device is preferably designed as a sieve belt with suction underneath.

The feed device preferably has a plurality of individually controllable, driven feed rollers and at least one driven opening roller which interacts with the feed rollers, with each feed segment being assigned its own feed roller. With this configuration, it is possible to generate almost any desired 3D profile of the profiled fiber accumulation or the profiled fleece intermediate product in a particularly reliable and targeted manner.

In a preferred embodiment, each draw-in roller is fed with its own fiber roving or its own fiber fleece strip. This increases the accuracy in forming the profiled fiber aggregation.

In preferred configurations, the profiled fleece is consolidated by needling, preferably in a double-needle machine. The needling preferably takes place in a needling machine in which the needle bar follows a substantially elliptical path during the needling. This avoids braking effects in the bonded fleece product.

The strength of the profiled nonwoven and thus also of the profiled, consolidated nonwoven product can be increased even further by pre-consolidating the covering nonwoven and possibly also the base nonwoven.

Brief description of the drawings

1

Fig. 12 is a schematic side view of a plant for carrying out an embodiment of the method according to the invention for forming a profiled, bonded nonwoven product;

2

Figure 12 is a schematic perspective view of an apparatus suitable for forming a profiled nonwoven intermediate or fiber aggregate;

3

Figure 12 is a schematic side view of another apparatus suitable for forming a profiled mat intermediate or fiber aggregate;

4

Figure 12 is a schematic side view of another apparatus suitable for forming a profiled mat intermediate or fiber aggregate;

figure 5

Figure 12 is a schematic representation of a portion of equipment useful in the formation of a profiled web;

6

Figure 12 is a schematic representation of a portion of equipment useful in the formation of a profiled bonded web product; and

Figure 7

Figure 12 is a schematic side view of an opening unit useful in the formation of a profiled batt or fiber aggregate.

In the context of this description, the term "fleece" is intended to include all possible accumulations of fibers or fiber flocks, including fiber flock mats and piles. The term "nonwoven intermediate" also includes discontinuous fiber aggregates. The same applies to the term "profiled fiber accumulation". For example, the intermediate fleece product or the profiled fiber aggregation can be formed by fleece strips spaced apart from one another.

Based on 1 a sequence of the method according to the invention is to be described as an example. A profiled nonwoven intermediate product 78 is formed by means of a feed device 22 on a transport device 10, which is preferably moved continuously in the transport direction T. The transport device 10 can be configured as a conveyor belt and preferably as a sieve belt with under suction. The speed of the transport device 10 is preferably in the range of 0.2 to 20 m/min, more preferably in the range of 0.5 to 10 m/min. The profiled fleece intermediate 78 can both be profiled as desired transversely to the transport direction T and in the transport direction T. The profiling of the fleece intermediate product 78 is merely indicated by a step shape shown schematically.

To generate the profile, the feed device 22, which has a plurality of feed segments 23 arranged horizontally next to one another (see 2 ) has, different amounts of fibers or fiber tufts per feed segment 23 are fed to the transport device 10 in a targeted manner. Details of the feeder 22 are provided below with reference to FIG Figures 2 to 4 described.

A measuring device 14 can measure the mass per unit area of the intermediate nonwoven product 78 formed across its width running transversely to the transport direction T in order to determine the transverse profile and, due to the movement of the transport device 10, also the longitudinal profile of the intermediate nonwoven product 78 formed. The measuring device 14 preferably comprises a plurality of measuring segments transverse to the transport direction T of the transport device 10 and a separate measurement is carried out in each measuring segment. In this way, the profile can be determined in two dimensions, i.e. in the longitudinal and transverse direction. The width of such a measuring segment is between 5 and 100 mm, preferably between 15 and 50 mm, more preferably between 20 and 25 mm. A belt scale can also be used.

The measuring device 14 can be designed in the form of a mechanical measuring device. It is also possible to design the measuring device 14 as a radiometric measuring device. In this case, either a radiometric measuring probe is arranged in each measuring segment, which uses radiometric measurements to determine the basis weight of the nonwoven intermediate product 78 in the respective measuring segment, or a single radiometric measuring probe is provided, which can be moved across the width of the nonwoven intermediate product 78 and records the weight per unit area of the nonwoven intermediate product 78 continuously or at specific measurement intervals. A combined use of both a radiometric and a mechanical measuring device 14 is also possible.

The results of the measuring device 14 are transmitted to a control or regulating device 20, which the feed device 22 on the basis of the results of the measuring device 14 to provide the desired non-uniform transverse and/or longitudinal profile of the intermediate web 78.

The profiled nonwoven intermediate product 78 is then fed to an opening unit 40, which dissolves the profiled nonwoven intermediate product 78 into fibers or fiber flocks. The opening unit 40 comprises at least one opening roller 42 provided with teeth or pins, which is preferably a turbo roller with a speed of at least 200 rpm, preferably at least 500 rpm, more preferably at least 1,000 rpm, more preferably at least 2,000 rpm. min, even more preferably at least 3,000 rpm. The opening roller 42 is preferably designed to be continuous over the entire width of the profiled nonwoven intermediate product 78, but can also consist of several segments lying next to one another.

With a diameter of the opening roller 42 of preferably 20 cm to 100 cm, more preferably 30 cm to 70 cm, the rotational speed of the opening roller 42 is at least 200 m/min, preferably at least 500 m/min, more preferably at least 1,000 m/min , and more preferably at least 2000 m/min.

In addition, the opening unit 40 comprises at least one draw-in roller 43 which is used to convey the incoming profiled nonwoven intermediate product 78 to the opening roller 42 . In the illustrated embodiment, the draw-in roller 43 and the opening roller 42 rotate in opposite directions. There is preferably exactly one draw-in roller 43 which runs over the entire width of the profiled nonwoven intermediate product 78 . However, several draw-in rollers 43 can also be arranged next to one another, which can be driven jointly or separately. A trough 44 supports the targeted feeding of the profiled fleece intermediate product 78 through the feed roller 43. In the present case, the trough 44 is designed as an overhead trough, but it can also be arranged under the feed roller 43.

The feed roller 43 preferably runs at the same speed as the transport device 10. In the transition between the transport device 10 and the feed roller 43, an auxiliary roller 45 can also be arranged.

In the example shown, the fibers or fiber tufts separated by the opening unit 40 are scattered as a profiled accumulation of fibers 50 onto a base fleece 66 which is transported in a conveying direction F on a conveyor device 16 below the opening unit 40 . The base fleece 66 is preferably provided on a base fleece roll-off 68 in the form of a roll and is drawn off from there in the direction of the opening unit 40 . The conveying direction F and the transport direction T are preferably identical, but can also be different. The speed at which the base fleece 66 is unwound preferably corresponds to the speed of the conveyor device 16.

The conveying device 16 is preferably designed as a screen belt, which is equipped with a suction device 70 . In any case, the undersuction 70 must be present in the area of the feed point for the fibers or fiber tufts fed from the opening unit 40, but is preferably present along the entire conveying path of the conveying device 16 in order to ensure safe transport of the fiber masses without blowing. In order to form the profiled fleece 80 , after the opening unit 40 , a covering fleece 72 is laid down from above onto the fibers or fiber tufts that have been opened up and fed in by the opening unit 40 . The cover fleece 72 is in turn preferably mounted in the form of a roll on a cover fleece roll-off 74 and can be pulled off from there in the conveying direction F. The speed at which the covering fleece 72 is unwound preferably corresponds to the conveying speed of the conveying device 16.

In the area of the conveyor device 16 , the profiled fleece 80 that is formed can be measured by a measuring unit 84 . The measuring unit 84 is preferably designed as described above with regard to the measuring device 14 . The results of the measuring unit 84 are preferably transferred to the open-loop or closed-loop control device 20 .

At the outlet of the conveyor device 16, the profiled fleece 80 is bonded in a bonding device 88, as a result of which a profiled, bonded fleece product 90 is produced. The consolidating device 88 is preferably designed as a needle machine, more preferably as a double-needle machine. Such a consolidation device 88 usually has a pair of feed rollers 92 and a pair of take-off rollers 93 .

The profiled, consolidated fleece product 90 formed during the consolidation can then be wound up again to form a roll 86, for example by means of a circumferential winder 94.

It is also possible for the consolidation device 88 to use thermal consolidation. Chemical impregnation with subsequent drying would also be conceivable. In addition to the illustrated winding of the end product, it is also possible to cut up the profiled, consolidated fleece product 90 into individual parts in a punch. It is also conceivable to feed the profiled, consolidated fleece product 90 to a deep-drawing device.

Similar to the supply of a covering fleece 72 after the opening unit 40 , an additional fleece (not shown) can also be deposited from above onto the fibers or fiber tufts fed from the feed device 22 in order to form the fleece intermediate product 78 . Likewise, the feed unit 22 can feed the fibers onto a starting fleece 12 that has already been conveyed (see 2 ) and thus form the profiled fleece intermediate product 78 . In addition to the 1 variant shown, to sprinkle the fiber material dissolved by the opening unit 40 onto a base fleece 66, the fiber material can also be sprinkled directly onto the conveyor device 16.

In principle, therefore, there is a whole series of options for producing the profiled nonwoven intermediate product 78 and the profiled nonwoven 80 that can be combined with one another as desired.

The profiled mat intermediate 78 can be formed solely by scattering or feeding fibers or fiber flocks in a 3D profile onto a conveyor 10. Likewise, the profiled mat intermediate 78 can be formed by feeding fibers or fiber flocks in a 3D profile an already existing starting fleece 12. In both of the aforementioned cases, an additional fleece can be deposited from above onto the profiled fiber accumulation. Finally, the profiled fleece intermediate product 78 can also be formed by feeding fibers or fiber flocks into a feeding device 22, which feeds fibers or fiber flocks evenly, and by subsequent targeted removal (e.g. suction) of fibers or fiber flocks at specific points to create the profile fiber extraction.

For the formation of the profiled fleece 80 there is first the possibility of dissolving the profiled fleece intermediate product 78 directly onto a conveyor device 16 as a profiled accumulation of fibers 50 . Likewise, the in 1 illustrated possibility of depositing the fibers or fiber tufts of the profiled nonwoven intermediate product 78, which have been dissolved in the opening unit 40, on a base nonwoven 66. In both of the aforementioned cases, the profiled fiber accumulation 50 is covered from above by a covering fleece 72 in order finally to obtain the profiled fleece 80 .

The intermediate web 78, the base web 66, and/or the cover web 72 may differ from one another in terms of material properties, thickness, staple lengths, and so forth. Through their selection, the profiled fleece 80 can be assigned specific properties in a very targeted manner.

The fleece intermediate product 78 can already consist of different layers, which then mix with one another during the opening process in the opening unit 40 .

In 2 a constructive embodiment of the alternative is shown, in which the feeding device 22 deposits fibers or fiber tufts onto a starting nonwoven 12 that has already been fed. A fiber tuft feeder 2 for producing the starting web 12 (in this case in the form of a fiber tuft mat) is provided in front of the feed device 22 . The fiber tuft feeder 2 can be designed in any commercially available variant and, in the example shown, has a discharge roller 48 at the lower end that extends across the width of the transport device 10 . The transport device 10 moves the output web 12 produced to the feed device 22. The feed device 22 is in the case of 2 also designed as a fiber tuft feeder. This fiber tuft feeder can be any commercially available fiber tuft feeder, but at its lower end it has a plurality of feed segments 23 arranged horizontally next to one another transversely to the transport direction T and which can be controlled separately from one another. Each feed segment 23 is assigned one of several discharge metering rollers 52 which are arranged next to one another over the width of the starting nonwoven 12 and can be controlled separately from one another. The width of the feed segments 23, which essentially corresponds to the width of the discharge metering rollers 52, is preferably between 5 mm and 100 mm, more preferably between 15 and 50 mm, even more preferably between 20 and 25 mm. The filling of the feeder 22 with Fiber flock material is fed via a feed pipe 54 which, like the feed pipe 58 of the fiber flock feeder 2, can branch off from a main feed line 60, as in the example shown. A change-over flap 56 can ensure switching between the two feed tubes 54 , 58 . Likewise, the two feed pipes 54, 58 can also be filled with fiber flock material via separate paths. The discharge dosing rollers 52 now give - under certain circumstances also on the basis of the measurement results of the measuring device 14 ( 1 ) and/or the measuring unit 84 ( 1 ) - each fiber flake material at the desired locations of the starting web 12 from to form a fiber mass profile. Each discharge metering roller 52 is connected to its own servo motor 62 for this purpose. Any desired profiling of the fleece intermediate product 78 is thereby produced in a targeted manner.

in the in 3 In the embodiment shown, the respective feed segments 23 of the feed device 22 are also arranged next to one another transversely to the transport direction T and are therefore not visible in the side view of the drawing. Each feed segment 23 is assigned a dispensing device 24 for storing and dispensing a roving 26 or a nonwoven strip. in the in 3 illustrated embodiment, the dispensing device 24 is designed as a coil, but it can also be designed as a sliver can or the like. The fiber roving 26 or the fiber fleece strip runs from the dispensing device 24, for example, to a preferably rubberized storage roller 28, which extends transversely to the transport direction T and horizontally, preferably over all feed segments 23, and one turn of each fiber roving 26 or each fiber fleece strip provided by the dispensing device 24 wound side by side around the storage roller 28. The storage roller 28 is driven in one direction of rotation (see the corresponding arrow in the drawing), preferably by means of a servo motor 30 and also preferably continuously at a relatively slow speed. In certain embodiments, the storage roller 28 can also be omitted.

in the in 3 In the illustrated embodiment, there is a one-piece storage roller 28, which simultaneously takes up the different strands of the roving 26 or the nonwoven strip of all feed segments next to one another. However, there can also be a separate storage roller for each feed segment.

Each feed segment 23 is also assigned a feed roller 32 which is driven by a servo motor 34 and also rotates in the same direction of rotation. The feed roller 32 withdraws the respective fiber roving 26 provided by the associated dispensing device 24 or the fiber fleece strip, either with the interposition of the storage roller 28 or directly. Although each feed segment 23 has its own feed roller 32, only one feed roller 32 can be seen in the drawing due to the sequential arrangement. Each feed roller 32 preferably has a set of teeth projecting backwards with respect to the direction of rotation.

A particular advantage of the interposition of the storage roller 28 is that the storage roller 28 slips under those fiber rovings 26 or fiber fleece strips that are only loosely wound around it. This therefore applies to all feed segments in which the feed roller 32 is not driven at all or runs slower than the storage roller 28. Only when a feed roller 32 runs faster than the storage roller 28 is the corresponding winding of the roving 26 or the nonwoven strip around the Storage roller 28 is pulled taut and the material is drawn in accordingly.

The feed rollers 32 may have any possible speed profile, including a plateau profile (e.g. in the form of a truncated pyramid) with plateaus of equal height but of different lengths depending on the desired delivery rate of fibrous material.

The fiber roving 26 moved along by the feed rollers 32 or the fiber fleece strip is preferably transported with the aid of a trough 33 to an opening roller 36 which is preferably designed in one piece and extends transversely to the transport direction T and horizontally over all feed segments 23. However, a separate opening roller per feed segment 23 can also be present.

In the example shown, the opening roller 36 is driven in the same direction of rotation as the feed rollers 32. In addition, the opening roller 36 preferably has a set of teeth that protrude forwards with respect to the direction of rotation, as a result of which it opens the twisted or compressed fiber flock material of the fiber roving 26 or the nonwoven strip particularly well. so that loose fiber flocks or even fine fibers are detached. These fall into a corresponding discharge chute 38 and are guided from there onto the transport device 10. Several discharge chutes 38 can also be provided next to one another for the various feed segments.

In the example shown, the centers of the draw-in rollers 32 and the opening roller 36 are arranged on a horizontal line. In addition to the arrangement shown, however, there are still many design options.

In a further development of the embodiment according to 3 shows 4 an enlarged view of an alternative embodiment of the feed device 22. Again, several feed rollers 32 arranged horizontally next to one another are provided, which can be controlled individually and each fed separately with fiber material (not shown). The fiber material conveyed by the feed rollers 32 is fed to the opening roller 36 with the aid of a trough 33, which is designed here as an overhead trough, and which detaches the fibers or fiber tufts from the fiber material. Unlike in the embodiment of 3 feed rollers 32 and opening roller 36 have opposite directions of rotation here. A blower 35 can be arranged above the roller nip in order to convey the fibers or fiber tufts released by the opening roller 36 downwards in the discharge chute 38 in a targeted manner.

In the illustrated embodiment, a discharge roller 37 is arranged at the lower end of the output chute 38, which is preferably designed as a rear-sucked screen roller. However, the discharge roller 37 can also only be designed as a screen roller, without rear suction. A roller with a perforated roller shell or a smooth roller are also conceivable as the discharge roller 37 .

Opposite the discharge roller 37 , a plurality of pedal recesses 39 are preferably provided, which are prestressed in the direction of the discharge roller 37 by spring force, for guiding the fibers or fiber tufts between the pedal recesses and the discharge roller 37 . One pedal recess 39 is preferably provided for each feed segment 23, and each of the pedal recesses 39 can be deflected individually. Due to the movable pedal recesses 39 and the rear suction of the discharge roller 37, a particularly targeted feeding of the individual fiber masses in the individual feed segments 23 is possible.

In addition to the possibilities presented so far, there is also the possibility of arranging the individual feed segments 23 of the feed device 22 in the transport direction T one after the other. In this case, the feed device 22 would preferably have to be movable over the width of the transport device 10 .

figure 5 FIG. 12 is a schematic representation of a portion of specific equipment that can be used in the formation of a profiled web 80. FIG. First, a web is produced in a first carding machine 102, which web is laid in a first web layer 104 to form a starting web 12. A 3D profile of fibers is then fed in a feeding device 22 onto the starting fleece 12 formed in this way. An additional nonwoven (or cover nonwoven) is deposited from above onto this fiber accumulation by means of a second nonwoven layer 108, which is fed by a second carding machine 106, in order to produce the profiled nonwoven intermediate product 78 in this way. This nonwoven intermediate product 78 is then fed to an opening unit 40 as previously described.

A base fleece 66 fed after the opening unit 40 can also be fed in by means of a fleece spreader, and a cover fleece 72 can also be fed in after the opening unit 40 by means of a fleece spreader.

6 FIG. 12 shows a schematic representation of a portion of equipment useful in forming the profiled, bonded nonwoven product 90. FIG. The fibers and fiber tufts opened by the opening unit 40 are first transported on a conveyor device 16 . A pre-needled base web 66, on which the profiled fiber accumulation is deposited, is now fed in by means of a pre-needling machine 110 arranged to the side of the conveying device. Finally, a second pre-needled nonwoven is fed in from above as a covering nonwoven 72 , so that ultimately a profiled nonwoven 80 in sandwich form is formed, which is fed to a bonding device 88 .

In the illustrated embodiment, the pre-needled batt formed by the pre-needling machine 110 is cut once in the middle to thereby form the base batt 66 and the cover batt 72 . The pre-needled base fleece 66 and the pre-needled cover fleece 72 are then fed "around a corner" by guiding the base fleece 66 or the cover fleece 72 around a 90-degree curve.

Theoretically, it is also conceivable for the starting fleece 12 or the additional fleece, which can be fed in from above in front of the opening unit 40, to be in the form of a pre-needled fleece.

With regard to the exact structural design of the supply of possible base and cover nonwovens, there were many options for the person skilled in the art.

In 7 a possible embodiment of the resolution unit 40 is shown. The nonwoven intermediate product 78 conveyed by the draw-in roller 43 is fed to the opening roller 42 with the aid of a trough 63, which is designed here as an overhead trough, which detaches the fibers or fiber flocks from the nonwoven intermediate product 78. Intake roller 43 and opening roller 42 here rotate in the same direction. But this can also be different.

In the example shown, the opening roller 42 carries the opened fiber material with it (e.g. with the aid of a further overhead trough). A blower 64 can be arranged on the side of the opening roller 42 opposite the draw-in roller 43 in order to convey the opened fibers or fiber tufts transported by the opening roller 42 downwards in a targeted manner in a discharge chute 65 . If there is no fan 64, the fibers or fiber tufts fall into the discharge chute 65.

In the illustrated embodiment, a discharge roller 67 is arranged at the lower end of the output chute 65, which is preferably designed as a rear-sucked screen roller. However, the discharge roller 67 can also only be designed as a screen roller, without rear suction. A roller with a perforated roller shell or a smooth roller are also conceivable as the discharge roller 67 .

A wall 69 is provided opposite the discharge roller 67 for guiding the fibers or fiber tufts. But it is also possible, similar to in 4 to provide several pedal recesses that can be individually deflected. With rear suction of the discharge roller 67, a particularly targeted feeding of the dissolved fiber masses is possible.

However, there are also many other possibilities for the specific configuration of the resolution unit 40 . For example, the scattering can take place directly at the transfer point between the draw-in roller 43 and the opening roller 42 (not shown). In this case it would be Output chute 65 under this nip and the direction of rotation of the opening roller 42 would be reversed. In addition, the fan 64 could then be located above the nip.

Overall, it is preferred to set the speed of the transport device 10 and the conveyor device 16 essentially the same in order to achieve an almost identical image of the fiber mass accumulations after the opening process. However, you can also deliberately change the speed ratio and adjust it in such a way that distortions arise with regard to the fiber mass contours.

When using a needling machine as the preferred form of a strengthening device 88 for strengthening the formed profiled nonwoven 80 and for producing the profiled, consolidated nonwoven product 90, the problem arises that the needles at thick points of the profiled nonwoven 80 have a longer needle path through the fiber material and thus on more or fewer needle notches come into contact with different points of the web. As a result, a higher compression would take place in the area of a thick point compared to a thin point. This could be compensated for, for example, by the needles in the needling machine only having a single notch, which fills up after a short puncture path and can then ineffectively continue further through the fleece without additional compression effects taking place at the thick points.

In principle, it is preferable to use double-needle machines, with which needles are applied from above and below, so that the previously produced profiled nonwoven 80 with its thick and thin points can be guided better through the constant distance between the perforated plates. It is preferred if the needle beams of the needling machine run through an elliptical path of movement and thus do not prevent the web from being transported in the conveying direction during bonding. This is the best way to avoid braking effects.

So far it has been mentioned that the feed device 22 can be controlled by means of the control or regulating device 20 . However, all other relevant machine parameters can also be controlled by the control or regulating device 20, such as the speeds of all components involved in the formation of the web.

In the description so far, the fiber material opened up by the opening unit 40 has been referred to as a profiled accumulation of fibers 50 . However, the formation of a profiled fiber aggregate 50 may be accomplished solely by the means previously described for formation of the intermediate nonwoven product 78. The fleece intermediate product 78 is then the profiled fiber accumulation 50, and this profiled fiber accumulation 50 can be further processed in the same way as the profiled fiber accumulation described so far in the text, i.e. it can be provided with a cover fleece 72, strengthened if necessary with a base fleece 66, etc The step of dissolving the nonwoven intermediate product 78 is then omitted.

Claims (12)

1. Method for forming a profiled, consolidated nonwoven-fabric product, comprising the following steps:

   - forming a profiled fibre cluster (50) or a profiled nonwoven-fabric intermediate product (78) which is a profiled fibre cluster;

   - feeding and depositing a covering nonwoven fabric (72) onto the profiled fibre cluster (50) from above to form a profiled nonwoven fabric (80) and consolidating the profiled nonwoven fabric (80) in a consolidating device (88) to form the profiled, consolidated nonwoven-fabric product (90), or feeding and depositing a covering nonwoven fabric (72) onto the profiled nonwoven-fabric intermediate product (78) from above to form a profiled nonwoven fabric and consolidating the profiled nonwoven fabric in a consolidating device to form the profiled, consolidated nonwoven-fabric product;

   characterized in that,

   to form the profiled nonwoven fabric (80), a base nonwoven fabric (66), on which the profiled fibre cluster (50) or the nonwoven-fabric intermediate product (78) is deposited, is fed such that the profiled nonwoven fabric (80) comprises a sandwich of base nonwoven fabric (66), profiled fibre cluster (50) or nonwoven-fabric intermediate product (78), and covering nonwoven fabric (72), and

   the profiled fibre cluster (50) is formed by a feeding device having multiple feeding segments (23) horizontally next to one another, or the profiled nonwoven-fabric intermediate product (78) is formed by a feeding device (22) having multiple feeding segments (23) horizontally next to one another.
2. Method according to Claim 1, characterized in that the profiled fibre cluster (50) is formed by previously forming the profiled nonwoven-fabric intermediate product (78) and breaking down the nonwoven-fabric intermediate product (78) in a breaking-down unit (40).
3. Method according to Claim 2, characterized in that the breaking-down unit (40) comprises at least one breaking-down roller (42) which is provided with teeth or pins and scatters the broken-down fibres or fibre flocks of the nonwoven-fabric intermediate product (78) as profiled fibre cluster (50) onto the base nonwoven fabric (66) or onto a conveying device (16) .
4. Method according to Claim 3, characterized in that the conveying device (16) is a sieve belt with under-suction (70).
5. Method according to Claim 3 or 4, characterized in that the at least one breaking-down roller (42) has a rotational speed of at least 200 revolutions/min, preferably at least 500 revolutions/min, more preferably more than 1000 revolutions/min, more preferably more than 2000 revolutions/min, even more preferably more than 3000 revolutions/min.
6. Method according to Claim 1, characterized in that the feeding device (22) has a plurality of individually actuatable, driven drawing-in rollers (32) and at least one driven opener roller (36) that interacts with the drawing-in rollers (32), wherein a dedicated drawing-in roller (32) is assigned to each feeding segment (23).
7. Method according to Claim 6, characterized in that each drawing-in roller (32) is supplied with a dedicated fibre sliver (26) or a dedicated nonwovenfleece strip.
8. Method according to one of the preceding claims, characterized in that the profiled nonwoven fabric (80) is consolidated by needling.
9. Method according to Claim 8, characterized in that the needling is carried out in a double-needle machine.
10. Method according to Claim 8 or 9, characterized in that the needling is carried out in a needle machine in which the needle bar follows a substantially elliptical path during the needling.
11. Method according to one of the preceding claims, characterized in that the covering nonwoven fabric (72) is pre-consolidated.
12. Method according to Claim 1, characterized in that the base nonwoven fabric (66) is pre-consolidated.

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