EP2584076B1 - Device and method for guiding and depositing synthetic filaments onto a non-woven fabric - Google Patents

Description

The invention relates to a device for guiding and depositing synthetic filaments into a nonwoven according to the preamble of claim 1 and to a method for guiding and depositing synthetic filaments into a nonwoven according to the preamble of claim 17.

For the production of so-called spunbond nonwovens, it is generally known that a plurality of extruded filaments after melt spinning and cooling are withdrawn together as a filament curtain, drawn and laid down on a storage belt to form a nonwoven. The deposited filaments lead to a fiber formation within the fleece, which among other things determine the strength of the fleece. In this case, the nonwoven strengths are usually determined in a so-called MD direction and a so-called CD direction. The MD direction is equal to the strip running direction, in which the nonwoven is fed continuously after deposition of the filaments. The CD direction is orthogonal to the MD direction and describes the strength of the web transverse to the direction of tape travel. Due to the moving tray, such nonwovens are formed predominantly with an MD-oriented storage of the filaments. This leads to a higher strength of the mat in the MD direction in relation to the strength in the CD direction. Depending on the product setting and polymer, a ratio between MD and CD formed from the strengths ranges between 1.5 and 3.5. For the production of technical products, however, spunbonded nonwovens are required, which have as much as possible a uniformly distributed nonwoven strength. For influencing the fiber formation, therefore, various devices are known in the art and methods known in order to obtain as uniform as possible a strength of the web in MD and CD direction of the web.

From the WO 2008/087 193 A2 a device and a method for guiding and depositing synthetic filaments to a nonwoven fabric is known, in which the filament curtain is drawn off by means of a draw-off nozzle and subsequently guided as a fiber flow in the direction of a storage belt. The fiber stream formed from a primary air of the draw-off nozzle and the filament curtain is passed through guide paths which are formed by a plurality of paired guide means. Thus, by cross-sectional changes and bottlenecks within the guide paths accelerations and expansions of the fiber stream can be generated, which in particular affect the filing of the filaments. In addition, air inlet slots are formed via the guide means below the extraction device, which allow the supply of secondary air. Essentially, the pressure conditions prevailing in the guide sections can be influenced.

In the known device and in the known method, the deposition of the fiber stream is essentially used by the cross-sectional changes within the guide paths and the associated fluidic influences to obtain a uniformly oriented as possible fiber formation within the web. However, this means that the fiber flow can predominantly be influenced only in one flow direction within the guide paths.

From the EP 1 340 842 A1 For example, a method and a device is known in which the withdrawal device is formed by a withdrawal channel, which is connected directly to a cooling device of the filaments. In this case, essentially the cooling air is used to guide the filament curtain through the extraction channel. The withdrawal channel are on the side facing the depositing belt side associated with a plurality of guide means which form a plurality of merge into one another guide paths for guiding the fiber flow. The guide means form a plurality of air inlet slots through which secondary air streams are supplied. The guide means form two diffuser-like guide sections which merge into one another, so that the fiber flow can be changed by cross-sectional constrictions and widenings. The deposition of the filaments is therefore also possible only by influencing the fiber flow in the flow direction. In order nevertheless to obtain the most uniform possible distribution of filaments during storage, a special divided into several zones suction device is assigned to the storage belt on the bottom. Thus, two different suction effects for receiving the filaments on the surface of the storage belt can be produced, but with the significant disadvantage that the filaments deposited with different intensities and lead to different densities of the web.

It is therefore an object of the invention to develop a generic device for guiding and depositing synthetic filaments to a nonwoven and a generic method for guiding and depositing synthetic filaments to form a nonwoven such that a fiber flow can be generated, the filaments to a uniform fiber formation in Tape running direction and transverse to the direction of tape travel leads.

A further object of the invention is to provide a method and an apparatus for guiding and depositing synthetic filaments into a nonwoven of the generic type with which spunbonded fabrics for technical applications having an MD / CD ratio of <1.5 are efficient can be produced with high production capacity. This object is achieved by a device having the features of claim 1 and by a method having the features of claim 17.

Advantageous developments of the invention are defined by the features and feature combinations of the subclaims.

The invention has the particular advantage that at least on the longitudinal side of the filament curtain along the working width, an air flow can be generated, which in particular can influence a transverse orientation of the filament shelf. For this purpose, the device according to the invention has at least at one of the air inlet slots a plurality of air guide elements arranged on one of the guide means. The air guide elements are assigned directly to the air inlet slot, so that the secondary air, which preferably flows in from the environment, occupies a flow direction predetermined by the air guide elements.

In order to make an influence on the fiber flow over the entire working width of the storage belt, the development of the device according to the invention is preferably used, in which the air guide over a width of the storage belt distributed side by side with an equal distance or a non-equal distance from each other are arranged. The number and distribution of the air guide elements are arbitrary, wherein the distribution of the air guide elements preferably extends parallel to the filament curtain.

In order to generate transverse flows which influence the fiber flow transversely to the depositing belt, the air guiding elements according to an advantageous development of the invention have at least one inclined guide surface, which guide surface generates a partial air flow directed transversely to the depositing belt when the secondary air flows in.

The air guide elements can be formed for this purpose by molding and / or obliquely held baffles. In this case, the guide elements can be arranged with different inclined guide surface within the air inlet slot. Thus, for example, the guide element associated with the middle region of the filament curtain can be designed with a more inclined guide surface in relation to the air guide elements arranged on the edge.

In addition, there is also the possibility that the air guide elements are designed to be adjustable in order to obtain a predefined angle adjustment of the guide surfaces depending on the product and method. For this purpose, the air guide elements are adjustably formed on the respective guide means, wherein the adjustment of the angular position can be done separately or collectively on the air guide elements. Thus, the air guide elements can be set with identical angular positions or with irregular angular positions in order to obtain, for example, in the central region of the working width or at the edge regions of the working width different flow effects in the filament strands.

In order for the partial flow of the secondary air generated by the air inlet slot to receive a partial flow directed in the direction of flow of the fiber stream, the development of the device according to the invention is particularly advantageous, in which the air inlet slot is formed between elongate guide ends which are interleaved with one another so that their leading ends are held vertically overlapping are. This forms an air inlet slot vertically aligned between the leading ends. The distance between the overlapping leading ends of the guide means forms a gap width of the air inlet slot.

Depending on the desired flow effects, the air guide elements may have a guide height projecting into the air inlet slot, which is equal to or smaller than the gap width of the air inlet slot extending between the leading ends of the guide means. Thus, in the case of air guide elements of the same size, the secondary air flow supplied via the air inlet slot can be supplied to the fiber flow in a multiplicity of partial flows.

In order to further improve the transverse orientation when depositing the filaments, the further development of the device according to the invention is particularly preferred, in which a plurality of separate air guiding means are assigned to an air inlet slot formed at the opposite guide means at the same height. Thus, predetermined secondary air streams can be introduced on both sides of the filament curtain, which thus act on the filaments on both sides of the fiber stream. In principle, it is also possible to arrange the opposing air guide elements at different heights on the guide means.

The opposing air inlet slots may be formed with rectified air guiding means or with oppositely directed air guiding means to obtain a predetermined influence on the fiber flow for depositing the filaments.

Thus, due to the fiber stream generated in the guide sections can produce an advantageous negative pressure for the suction of the secondary air, the device according to the invention is particularly advantageous, in which the guide means are formed by a plurality of shaped sheets, which acts as a first pair of mold sheets acting as a diffuser inlet run and a second pair of mold sheets form a working as a diffuser discharge line. Thus, the transition region between the metal plate pairs is particularly suitable to suck in the desired secondary air via an air inlet slot. In that regard, the development of the device according to the invention is provided, in which the air inlet slots with are formed in each case a plurality of air guiding means between the two mold plate pairs.

To realize high production speeds in the production of the nonwoven fabric, the development of the invention has proven particularly useful, in which the extraction device has a discharge nozzle with a guide channel and several opening into the guide channel nozzle channels, wherein the nozzle channels are connected to a compressed air source. This can be used to generate a primary air stream with the trigger device, which subtracts the filament curtain after the melt spinning with high intensity and blows under stretching in the subsequent routes.

In order to be able to counteract the negative pressure which is directly on the outlet side of the drawing-off nozzle, two opposite air inlet slots without air guiding means are formed directly below the drawing nozzle in the opposite guide means, the gap widths of the air inlet slots being adjustable. In particular, the pressure conditions during the generation of the fiber flow in the guide paths can be advantageously influenced.

In order to make possible the deposition of the fibers without further supply of secondary air, the storage belt is assigned a compensating roller pair on a belt outlet side, wherein form a seal between a the conveyor belt facing the leading end of the guide means and one of the compensation rollers of the compensation roller pair. In addition, the fleece can be preconsolidated by the compensation rollers, wherein the compensation rollers are preferably designed to be heated.

On the opposite inlet side of the storage area above the storage belt is advantageous by a shield against the Environment shielded, which is connected to a storage tape facing the leading end of the guide means. Thus, the fiber flow can be deposited on the outlet side of the guide without secondary air influence.

To accommodate the air and to support the filing of the fibers, the storage tape on a bottom is assigned a vacuum box according to an advantageous embodiment of the invention, which is connected to a vacuum source and which has an adjustable suction opening relative to the underside of the storage belt. Thus, depending on the process and method different suction effects on the surface of the storage belt can be generated.

The method according to the invention can also be used independently of the device according to the invention in order to influence a fiber stream generated for depositing the filaments in such a way that a filing of the filaments which is uniformly distributed in the direction of travel and in the direction of the strip running direction. For this purpose, at least one of the partial streams of the secondary air is fed laterally next to the filament curtain at an inflow angle transversely to the depositing belt the fiber stream. In particular, transversely flowing partial flows can thus be produced laterally next to the fiber flow within the guide path, so that a transverse component for distributing the filaments acts on the fiber flow.

The effect according to the invention can be advantageously improved in that a plurality of secondary streams of the secondary air are fed to the fiber stream parallel to both sides of the filament curtain at the inflow angle transversely of the deposition belt. Thus, both rectilinear and opposite transverse flows can be generated on the filament curtain.

The partial flows can be supplied to the fiber flow both on both sides of the filament curtain and on one side of the filament curtain with different inflow angles. Thus, the effect of the cross flow on the respective process and polymer type and filament titer can be adjusted.

The method according to the invention can be used particularly effectively in the variant in which the partial flow of the secondary air is supplied to the fiber flow between two guide sections, each of which acts as a diffuser. In this way, the pressure conditions acting within the guide paths can advantageously be utilized in order to obtain a maximum of inflowing secondary air.

The secondary air is preferably drawn in from the environment. In principle, however, it is also possible to supply the secondary air directly through an additional air source to the air inlet slots.

The device according to the invention for guiding and depositing synthetic filaments into a nonwoven as well as the method according to the invention for guiding and depositing synthetic filaments to form a nonwoven are described in more detail below with reference to some embodiments of the device according to the invention.

Fig. 1

schematisch eine Querschnittansicht eines ersten Ausführungsbeispiels der erfindungsgemäßen Vorrichtung

Fig. 2

schematisch eine Seitenansicht des Ausführungsbeispiels aus Fig. 1

Fig. 3

schematisch eine Querschnittansicht eines weiteren Ausführungsbeispiels der erfindungsgemäßen Vorrichtung

Fig. 4

schematisch eine Schnittdarstellung gegenüberliegender Führungsmittel mit Lufteinlassschlitzen

Fig. 5

schematisch eine Ansicht eines der Führungsmittel aus Fig. 4

Fig. 6

schematisch eine Seitenansicht eines Führungsmittels mit Luftleitelementen

Fig. 7

schematisch eine Querschnittansicht eines weiteren Ausführungsbeispiels der erfindungsgemäßen Vorrichtung

They show:

Fig. 1

schematically a cross-sectional view of a first embodiment of the device according to the invention

Fig. 2

schematically a side view of the embodiment of Fig. 1

Fig. 3

schematically a cross-sectional view of another embodiment of the device according to the invention

Fig. 4

schematically a sectional view of opposing guide means with air inlet slots

Fig. 5

schematically a view of one of the guide means Fig. 4

Fig. 6

schematically a side view of a guide means with air guide elements

Fig. 7

schematically a cross-sectional view of another embodiment of the device according to the invention

In the Fig. 1 and 2 a first embodiment of the device according to the invention for guiding and depositing synthetic filaments to a nonwoven fabric is shown in several views. Fig. 1 shows the embodiment schematically in a cross-sectional view and Fig. 2 in a side view. Unless expressly related to any of the figures, the following description applies to both figures.

The embodiment has a take-off device 1 for pulling a plurality of filaments extruded by means of a spinning device together as a filament curtain. The filament curtain is in the Fig. 1 and 2 drawn for better understanding of the device parts and identified by the reference numeral 19.

The extraction device 1 is formed in this embodiment by a discharge nozzle 2, which is composed of two nozzle halves 2.1 and 2.2. Each of the nozzle halves 2.1 and 2.2 contains a pressure chamber 5 and at least one nozzle channel 4 opening into the guide channel 3. The pressure chamber 5 of the nozzle halves 2.1 and 2.2 are through Compressed air connections 29 are connected to a compressed air source, not shown here, so that via the nozzle channels 4 in the guide channel 3, a compressed air is introduced.

Below the trigger device 1, a storage belt 20 is arranged, which is preferably designed as an endless belt and is driven, for example via a tape roll 21 in a tape running direction. The tape running direction is in Fig. 1 marked with an arrow. The storage belt 20 is gas permeable and could for example be designed as a sieve or fabric tape.

Above the depositing belt 20, a plurality of guide means 6.1 to 6.4 are arranged between the extraction device 1 and the storage belt 20 to form a plurality of overlapping guide sections 11.1 and 11.2. The guide means 6.1 to 6.4 are arranged in pairs parallel to the nozzle halves 2.1 and 2.2 of the discharge nozzle 2 such that form between the opposite guide means 6.1 and 6.2 and 6.3 and 6.4 in extension of the guide channel 3, the guide sections 11.1 and 11.2.

In this exemplary embodiment, the guide means 6.1 and 6.2 are formed by the shaped sheets 9.1 and 9.2 and the guide means 6.3 and 6.4 by the shaped sheets 10.1 and 10.2. The forming plate pair 9 of the forming plates 9.1 and 9.2 thereby constitutes a feed line 11.1 formed as a diffuser 12.1 and the forming plate pair 10 of the forming sheets 10.1 and 10.2 constitute a discharge section 11.2 designed as a diffuser 12.2. The leading ends 17.1 and 17.2 of the forming sheets 9.1 and 9.2 and the leading ends 18.1 and 18.2 of the metal sheets 10.1 and 10.2 are arranged overlapping and form between each one air inlet slot 8.1 and 8.2. the overlapping guide ends 17.1 and 17.2 and 18.1 and 18.2 form a vertically oriented air inlet slot 8.1. and 8.2, the gap width is determined by the distance between the leading ends 17.1 and 18.1 and 17.2 and 18.2.

The formed on a discharge side 37 air inlet slot 8.1 between the guide means 6.1 and 6.3 has in this embodiment a plurality of air guide elements 13. The air guide elements 13 are arranged on the upper guide end 18.1 of the guide means 6.3 and protrude with a guide surface 16 into the air inlet slot 8.1.

As from the illustration in Fig. 2 As can be seen, a plurality of air guide elements 13 are distributed uniformly over the width of the storage belt 20 at the upper guide end 18.1 of the molded sheet 10.1. Between the air guide elements 13 an equally large distance is formed in each case. The air guide elements 13 are formed in this embodiment by an elongated shaped body 15, the upper side of which forms an inclined guide surface 16. The inclination of the molded body 15 is aligned in this embodiment over the entire width of the storage belt 20 the same.

As from the illustration in Fig. 1 and 2 It can be seen that two further opposing air inlet slots 7.1 and 7.2 are formed directly below the draw-off nozzle 2 between the draw-off nozzle 2 and the adjacent guide means 6.1 and 6.2. The air inlet slots 7.1 and 7.2 are each associated with a louver 28.1 and 28.2, through which an opening cross-section of the air inlet slots 7.1 and 7.2 is adjustable in size.

At the opposite end of the guide means 6.3 and 6.4, the storage belt 20 is arranged at a short distance from the guide means 6.3 and 6.4. The storage area for the filaments of the filament curtain 19 which forms between the shaped sheet metal pair 10 and the storage belt 20 are provided on an inlet side 38 and on a discharge side 37 respectively sealing elements. The top of the storage belt 20 is shielded on the inlet side 38 by a shield plate 27 from the environment, wherein the shield plate 27 is attached to the mold plate 10.2. On the discharge side 37, the storage belt 20 is assigned a compensation roller pair 26, wherein one of the compensation rollers 26.1 is arranged on the upper side of the storage belt 20 and the opposite compensation roller 26.2 on an underside of the storage belt. On the upper side of the storage belt 20, a sealing strip 31 is arranged between the compensation roller 26.1 and the shaped metal sheet 10.2, so that the storage area on the upper side of the storage belt 20 is shielded from the environment.

However, depending on the design of the ends of the sheet metal pair 10, it is also possible to operate the storage area on the inlet side 38 without an additional shielding and on the drain side without an additional sealing strip.

As in particular from the illustration in Fig. 2 As can be seen, the sides of the metal sheets 10.1 and 10.2 are shielded in the storage area of the storage belt 20 by sealing plates 30.1 and 30.2 from the environment. In that regard, the storage area on the top of the storage belt 20 is substantially shielded from the environment.

As from the illustration in Fig. 1 shows, a vacuum box 22 is disposed on the underside of the storage belt 20, which sucks directly with a suction port 23, the bottom of the storage belt 20 in the fiber tray. The vacuum box 22 is for this purpose connected via a suction port 25 with a vacuum source, not shown here. In this exemplary embodiment, the suction opening 23 is assigned an adjustable flap 24, by means of which the suction opening 23 can be changed in size.

This in Fig. 1 and 2 illustrated embodiment of the device according to the invention is combined in operation with a spinning device not shown here. Thus, the spinning device could have a nozzle block with a row-shaped arrangement of a plurality of nozzle bores and a cooling device formed below the nozzle block be formed. The filaments produced in the spinning device are guided as a filament curtain 19 and sucked through the draw-off nozzle 2 into the guide channel 3. The filaments of the filament curtain 19 are stretched and conveyed through the draw-off nozzle 2. The filament curtain 19 is blown out of the guide channel 3 as a fiber stream together with the primary air generated by the exhaust nozzle 2 and blown into the adjacent inlet section 11.1 of the molded sheets 9.1 and 9.2. Due to the high flow velocities, a negative pressure is created which sucks a secondary air from the environment via the air inlet slots 7.1 and 7.2 on the underside of the draw-off nozzle 2. The incoming secondary air can be adjusted continuously by adjusting the air inlet slots 7.1 and 7.2 through the adjustment flaps 24.1 and 24.2. Due to the supplied secondary air, the flow velocity of the fiber stream is increased at a narrowest cross-section of the inlet section 11.1 formed as a diffuser and then braked by the cross-sectional widening between the forming plates 9.1 and 9.2. When exiting the inlet section 11.1, a secondary air is drawn in again through the air inlet slots 8.1 and 8.2. In this case, the secondary air sucked in through the air inlet slot 8.1 is guided by the air guiding elements 13 in accordance with the orientation of the air guiding elements 13. Thus, when the secondary air flows in through the respective guide surfaces 16 of the air guiding elements 13, a partial flow generated transversely to the depositing belt 20 is produced laterally next to the filament curtain 19, which acts as a secondary air flow on the fiber flow. The crossflows of the incoming secondary air acting on the fiber flow leads to a deflection of the filaments and thus brings about an improved transverse orientation during the deposition of the filaments.

Due to the cross-sectional widening between the metal sheets 10.1 and 10.2, the fiber flow is decelerated and deposited directly on the storage belt. The distance between the metal sheets 10.1 and 10.2 and the storage belt 20 is in this embodiment to a set predetermined distance value. However, this distance can also be carried out advantageously adjustable, so that depending on the process and polymer type, a predetermined distance between the outlet of the guide means 6.3 and 6.4 and the storage belt 20 is adjustable.

The filing of the fiber stream and the absorption of the superfluous air is supported by the suction effect of the vacuum box 22. The suction opening 23 is set for this purpose to a predetermined opening area, so that a defined formation area for filing the filaments is formed.

By the shielding plate 27 on the inlet side 38 and the sealing strip 31 and the compensation roller 26.1 the suction of further secondary air is avoided. In that regard, the filing of the filaments is determined by the fiber flow, which is composed of the primary air and the supplied partial streams of secondary air. It is essential here that at least one of the partial streams of the secondary air is supplied to the fiber stream laterally next to the curtain at an inflow angle transversely to the depositing belt. By means of these partial flows directed transversely to the depositing belt 20, the fiber flow for producing predefined fiber orientations can be influenced in such a way that the strength of the produced nonwoven fabric is uniformed to a high degree, so that the nonwoven material has approximately the same strength values both in the MD direction and in the CD direction , The webs thus produced are thus particularly suitable for use, for example, for filter substrates, underlays or geo-textiles. The nonwovens produced therewith are distinguished by an MD / CD ratio in the range from 1.0 to 1.5.

In order to obtain approximately the same strength both in the strip running direction and transversely to the strip running direction, this is in Fig. 3 illustrated embodiment particularly suitable. The embodiment according to Fig. 3 is essentially identical to the embodiment according to Fig. 1 and 2 , so that at this point only the differences will be explained and otherwise reference is made to the above description.

At the in Fig. 3 illustrated embodiment, the opposite air inlet slots 8.1 and 8.2 between the pairs of mold plates 9 and 10 are each carried out with air guide elements 13.1 and 13.2. Thus, the secondary air sucked in on the feed side 38 and the secondary air sucked in on the discharge side 37 can advantageously be guided by the guide elements 13.1 and 13.2 such that the partial streams of the secondary air are fed to the fiber flow at certain inflow angles transversely of the deposit belt on both sides of the filament curtain. The air-guiding elements 13.1 and 13.2 associated with the air inlet slots 8.1 and 8.2 may in this case be identical, for example, as baffles or molded bodies.

In the embodiments according to Fig. 1 to 3 the extraction nozzle 2 and the guide means 6.1 to 6.4 are usually held in a machine frame. The flexibility for the production of different nonwovens and for the processing of different products can thereby be further increased by the withdrawal nozzle 2 and the guide means 6.1 to 6.4 are kept adjustable in height. Thus, a distance formed between the draw-off nozzle 2 and the storage belt 20 can be changed. Likewise, a vertical distance of the sheet metal pairs 9 and 10 could be adjustable. In addition, the arranged on the inlet side 38 of the form sheets 9.2 and 10.2 are connected to a nozzle half of the suction nozzle 2 such that they can be moved back and forth together between an operating position and a maintenance position. In the maintenance position, the nozzle half of the suction nozzle 2 and the metal sheets 9.2 and 10.2 are held so that a cleaning of the guide channel 3 and a start of the process is possible.

In 4 and 5 is an embodiment of a possible embodiment of the Luftleitschlitze 8.1 and 8.2 shown schematically. In Fig. 4 is a sectional view of the air inlet slots 8.1 and 8.2 in the mold plate pairs 9 and 10 shown schematically in a section and Fig. 5 represents a view of a leading end 17.1 one of the shaped sheets 9.1 with arranged air guide elements 13.1.

As from the illustration in Fig. 4 As can be seen, the air guide elements 13.1 are formed identically in the air inlet slot 8.1 and in the air inlet slot 8.2. The air guiding elements 13.1 and 13.2 have a guide height projecting into the air inlet slots 8.1 and 8.2, which is smaller than a gap width of the air inlet slots 8.1 and 8.2. The guide height of one of the air guide elements 13.2 is in Fig. 4 defined by the reference L. The gap width of the associated air inlet slot 8.2 is marked with the reference symbol S. Thus, in this embodiment S> L.

The relation between the guide height S and the gap width L can also be advantageously adjusted by movable outer guide ends 18.1 and 18.2 of the metal sheets 10.1 and 10.2 or by moving inner guide ends 17.1 and 17.2 of the metal sheets 9.1 and 9.2, wherein the air guide elements 13.1 and 13.2 act as a stop to get a setting with S = L. Thus, the air guide elements 13.1 and 13.2 would extend over the entire distance between the metal sheets 9.1 and 10.1 and the metal sheets 9.2 and 10.2.

As from the illustration in Fig. 5 it can be seen, the air guide elements 13.1 and 13.2 are each designed as a shaped body 15 with a triangular shape. In that regard, each of the shaped bodies 15 has two inclined guide surfaces 16, which form an inlet angle α relative to a vertical inflow direction of the secondary air. The inflow angle α is directed transversely to the flow direction of the fiber flow and thus generates a Direction of the filaments directed transversely to the depositing belt within the fiber stream. Depending on the design of the guide elements 13.1 and 13.2, these flow effects generated by the guide elements 13.1 and 13.2 can be advantageously used to influence the fiber flow in accordance with the desired deposit.

In principle, however, it is also possible to arrange the air guide elements 13.1 and 13.2 in the air inlet slots 8.1 and 8.2 with opposite orientations. For example, in Fig. 6 an embodiment shown in which at the upper guide end 18.1 and 18.2 of the mold sheets 10.1 and 10.2 a plurality of mutually spaced air guide elements 13.1 and 13.2 are arranged in the form of baffles 14. The baffles 14 have an inclined to guide the sucked secondary air guide surface. The guide elements 13.1 arranged at the leading end 18.1 of the shaped metal sheet 10.1 are shown in a solid line. The invisible and in the underlying air inlet slot 8.2 arranged air guide 13.2 at the leading end 18.2 of the sheet metal 10.2 are shown in dashed lines and have an opposite inclination of the guide surfaces 16. In that regard, differently oriented partial streams of secondary air are generated on both sides of the filament curtain, which act accordingly on the fiber flow.

The angular position of the guide plates 14 can be adjusted in this embodiment, so that the inflow angle formed by the guide plates 14 can be changed. The adjusting mechanism could for this purpose be designed such that all baffles 14 held at a leading end 18.1 or 18.2 can be set collectively in the desired angular position. The adjustment mechanism could also allow a single adjustment to the baffles 14, so that individual adjustment per baffle would be possible.

The method according to the invention and the device according to the invention thus offer a high degree of flexibility for the individual influencing of the fiber flow in order to obtain a desired fiber orientation during the filing of the filaments.

In Fig. 7 a further embodiment of the device according to the invention is shown together with a spinning device. In the in the Fig. 7 illustrated embodiment, only a cross-sectional view is shown.

The embodiment according to Fig. 7 has a heatable spinning beam 32, which has on its underside an elongated spinneret with a plurality of nozzle bores. The spinneret is not shown here. Below the spinning beam 32, a cooling device 33 is provided, which has two pressure chambers 34.1 and 34.2 laterally next to the spinning beam 32, which form a spinning shaft 39 via a respective blowing wall.

Below the cooling device 33, a trigger device 1 is arranged, which forms an extraction channel 35 in extension to the spinning shaft 39. The discharge channel 35 is sealingly connected to the cooling device 33, so that the cooling air of the cooling device 33 is guided together with the filament curtain through the discharge channel 35. On the outlet side of the discharge channel 35 a plurality of mold plate pairs 9 and 10 are arranged, between each of which a diffuser 12.1 and 12.2 is formed. Between the draw-off device 1 and the first shaped sheet metal pair 9, the air inlet slots 7.1 and 7.2 are formed, through which the inflow of secondary air is regulated. In the further course of the guide sections 11.1 and 11.2 further air inlet slots 8.1 and 8.2 are formed between the first diffuser 12.1 and the second diffuser 12.2, which are each assigned a plurality of air guide elements 13.1 and 13.2. The function and design of the air guide elements 13.1 and 13.2 in the air inlet slots 8.1 and 8.2 is identical to the aforementioned embodiments, so that at this point for this no further explanation.

On the storage belt 20 facing the end of the mold sheets 10.1 and 10.2 the storage area is sealed by two guided on the top of the storage belt 20 sealing rollers 36.1 and 36.2. Between the sealing rollers 36.1 and 36.2, a vacuum box 22 is provided on the underside of the storage belt 20, which is connected to a suction port 23 and a vacuum source, not shown. The storage belt 20 is also made gas-permeable in this embodiment and driven as an endless belt not shown here drives in the tape running direction. To improve the seal, the sealing rollers 36.1 and 36.2 could also be assigned lower rollers, which would be held on the underside next to the vacuum box 22.

At the in Fig. 7 illustrated embodiment, the generation of the primary air is carried out substantially by the cooling air. Thus, the fiber flow generated by the extraction device 1 is formed by the cooling air and the filament curtain, which is influenced in the further course of the leadership of the fiber stream by the supplied secondary air.

The guide means used in the illustrated embodiments for producing one or more guide paths of the fiber stream, are exemplary. Basically can be used as a guide arbitrarily shaped metal sheets or rollers or other shielding to form the guidances. It is essential here that a secondary air sucked in through an air inlet slot is directed via suitable air guide elements in such a way that a partial flow of the secondary air flows in a direction transverse to the depositing belt and thus influences the deposition of the fibers in the fiber stream.

Furthermore, in the illustrated embodiments, the secondary air flow has been generated in each case from the environment. In principle, however, there is also the possibility that in the exemplary embodiments shown, an additional air source is connected to one or both of the air inlet slots containing the air guide elements. In that regard, the secondary air can also be actively fed through an air source.

LIST OF REFERENCE NUMBERS

1

off device

2

navel

2.1

nozzle half

2.2

nozzle half

3

guide channel

4

nozzle channel

5

pressure chamber

6.1, 6.2, 6.3, 6.4

guide means

7.1, 7.2

Air intake slot

8.1, 8.2

Air intake slot

9

Formblech couple

9.1, 9.2

Formblech

10

Formblech couple

10.1, 10.2

Formblech

11.1, 11.2

guide path

12.1, 12.2

diffuser

13, 13.1, 13.2

air guide

14

baffle

15

moldings

16

baffle

17.1, 17.2

lead end

18.1, 18.2

lead end

19

filament curtain

20

depositing belt

21

tape roll

22

vacuum

23

suction opening

24

adjustment flap

25

suction

26

Compensation roller pair

26.1, 26.2

compensation roller

27

shield

28.1, 28.2

louver

29

Compressed air connection

30.1, 30.2

sealing plates

31

sealing strip

32

spinning beam

33

cooling device

34.1, 34.2

pressure chamber

35

culvert

36

sealing rollers

37

outlet side

38

supply side

39

spinning shaft

Claims (20)

1. Apparatus for the guidance and depositing of synthetic filaments to a nonwoven fabric having a drawing device (1) having a drawing nozzle (2), with a deposit belt (20) disposed beneath the drawing device (1), and having numerous guidance means (6.1 - 6.4) disposed between the drawing device (1) and the deposit belt (20), which form, in pairs, numerous merging guidance pathways (11.1, 11.2) for jointly guiding a filament curtain formed by the filaments and a primary airstream generated by the drawing nozzle (2), wherein the guidance means (6.1 - 6.4) exhibit numerous air intake slits (8.1, 8.2) beneath the drawing device (1), which enable an introduction of a secondary airstream, characterized in that numerous air conducting elements (13) disposed on one of the guidance means (6.1 - 6.4) are dedicated to at least one of the air intake slits (8.1), wherein the air conducting elements (13) are suitable for guiding the secondary airstream such that a sub-stream of the secondary airstream flows transverse to the deposit belt (20).
2. Apparatus according to Claim 1, characterized in that the air conducting elements (13) are distributed adjacently over a width of the deposit belt (20), disposed with a uniform spacing or an uneven spacing in relation to one another.
3. Apparatus according to Claim 1 or 2, characterized in that the air conducting elements (13) have at least one inclined conducting surface (16), wherein said conducting surface (16) generates a sub-stream oriented transverse to the deposit belt (20) with the inflow of a secondary airstream.
4. Apparatus according to Claim 3, characterized in that the air conducting elements (13) are formed by means of shaped bodies (15) and/or by means of diagonally mounted conducting plates (14).
5. Apparatus according to one of the Claims 1 - 4, characterized in that the air conducting elements (13) are mounted on one of the guidance means (6.1 - 6.4) in such a manner that they can be adjusted with respect to their angular position.
6. Apparatus according to one of the Claims 1 - 5, characterized in that the air intake slit (8.1) is formed between two longitudinal guide ends (17.1, 18.1) of two guidance means (6.1, 6.3) disposed below one another, wherein said guide ends (17.1, 18.1) are held such that they overlap vertically.
7. Apparatus according to Claim 6, characterized in that the air conducting elements (13) are of a height which is the same or less than a gap width of the air intake slit (8.1) extending between the guide ends (17.1, 18.1) of the guidance means (6.1, 6.3).
8. Apparatus according to one of the Claims 1 - 7, characterized in that numerous separate air conducting agents (13.2) are dedicated at the same height to one of the air intake slits (8.2) formed on the opposite guidance means (6.2, 6.4).
9. Apparatus according to Claim 8, characterized in that the opposing air intake slits (8.1, 8.2) are formed with air conducting agents (13.1, 13.2) oriented in the same direction, or with air conducting agents (13.1, 13.2) oriented in opposing directions.
10. Apparatus according to one of the Claims 1 - 9, characterized in that the guidance means (6.1 - 6.4) are formed by means of numerous shaped sheets (9.1, 9.2, 10.1, 10.2), wherein a first shaped sheet pair (9) is designed as an intake path (11.1) acting as a diffusor (12.1), and a second shaped sheet pair (10) is designed as a discharge path (11.2) acting as a diffusor (12.2).
11. Apparatus according to Claim 10, characterized in that the air intake slits (8.1, 8.2) are designed having numerous air conducting agents (13.1, 13.2) between the two profiled sheet pairs (9, 10).
12. Apparatus according to one of the Claims 1 - 11, characterized in that the drawing device (1) is formed by means of a drawing nozzle (2) having a guidance channel (3) and numerous nozzle channels (4) opening into the guidance channel (3), wherein the nozzle channels (4) are connected to a pressurized air source.
13. Apparatus according to Claim 12, characterized in that the opposing guidance means (6.1, 6.2) form two opposing air intake slits (7.1, 7.2) without air conducting agents directly beneath the drawing nozzle (2), and that the gap widths of the air intake slits (7.1, 7.2) are designed such that they can be adjusted.
14. Apparatus according to one of the Claims 1 - 13, characterized in that a roller pair (26) is dedicated to the deposit belt (20) at a belt end (37), wherein a seal (31) is formed between a guide end of a guidance means (6.4) facing the deposit belt (20) and one of the rollers (26.1) of the roller pair (26).
15. Apparatus according to Claim 14, characterized in that a shielding plate (27) is dedicated to the deposit belt (20) at an intake end (38), which is connected to one of the guide ends of the guidance means (6.4) facing the deposit belt (20).
16. Apparatus according to one of the Claims 1 - 15, characterized in that a vacuum box (22) is dedicated to the deposit belt (20) on its lower surface, which is connected to a vacuum source and has an adjustable suction opening (23) opposite the lower surface of the deposit belt (20).
17. Method for the guidance and depositing of synthetic filaments to a nonwoven fabric, with which a plurality of extruded filaments, after having been cooled, are drawn and stretched in the form of a filament curtain by means of a generated primary airstream, wherein the filament curtain, together with the primary airstream is guided as a fiber stream in the direction of a deposit belt through a plurality of guidance means disposed between the drawing device and the deposit belt, which form, in pairs, a plurality of merging guidance pathways, and wherein numerous sub-streams of a secondary airstream are guided toward the fiber stream for the purpose of influencing a fiber formation in the nonwoven fabric, characterized in that at least one of the sub-streams of the secondary airstream is introduced to the fiber stream laterally adjacent to the filament curtain at an inflow angle that is transverse to the deposit belt.
18. Method according to Claim 17, characterized in that numerous sub-streams of the secondary airstream are introduced to the fiber stream parallel to both sides of the filament curtain at an inflow angle that is transverse to the deposit belt.
19. Method according to Claim 18, characterized in that the sub-streams of the secondary airstream are introduced to the fiber stream with different inflow angles.
20. Method according to Claims 17 - 19, characterized in that the sub-stream of the secondary airstream between two guidance pathways, each acting as a diffusor, are introduced to the fiber stream.

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