EP2452001A1

EP2452001A1 - Apparatus for forming a sliver

Info

Publication number: EP2452001A1
Application number: EP10732257A
Authority: EP
Inventors: Ueli Stutz; Daniel Sommer
Original assignee: Maschinenfabrik Rieter AG
Current assignee: Maschinenfabrik Rieter AG
Priority date: 2009-07-10
Filing date: 2010-07-06
Publication date: 2012-05-16
Anticipated expiration: 2030-07-06
Also published as: JP5518189B2; CN102471948B; CH701420A2; CN102471948A; EP2452001B1; JP2012532256A; WO2011003216A1

Abstract

The invention relates to an apparatus for forming a sliver (F1) from a fibrous nonwoven (V) which is formed at a combing point (1) of a combing machine and is fed to a clamping point (31) of a roll pair (17, 30) which consists of a roll (17) connected to a drive and a pressure roll (30), and, as viewed in the conveying direction (F), the fibrous nonwoven is collected following the clamping point (31) and is fed via a funnel (39) to a press-roll pair (K) which is connected to a drive (G, M). In order to simplify the apparatus and avoid wrong drafts, it is proposed that, following the clamping point (31) of the roll pair (17, 30), as viewed in the conveying direction (F), the fibrous nonwoven (V) is transferred in the region of the circumferential surface (U) of the driven roll (17) to the funnel (39) and the following press-roll pair (K), and one of the press rolls (K1) of the press-roll pair (K) is arranged fixedly in terms of rotation and coaxially on the driven roll (17).

Description

Apparatus for forming a sliver

The invention relates to a device for forming a sliver of a formed at a Kämmstelle a comber nonwoven fabric according to the preamble of the main claim.

From the practice devices are known, wherein the, formed at a Kämmstelle a combing machine nonwoven fabric of a nip of a pair of rollers is fed and then removed eccentrically (transversely) and a funnel for

Band formation is supplied. In this case, the funnel (also called compressor) is followed by a calender roller pair connected to a drive, via which the fiber sliver formed is delivered to a subsequent conveyor table. Such a device is z. As shown and described in published DE 103 00 317 A1.

Furthermore, a device is known from WO 2006/012758 A1, wherein the, withdrawn from a take-off device and combed fiber packets for

Fleece formation are delivered to a connected to a vacuum source screen drum. The screen drum is provided with a drive and conveys the formed nonwoven fabric in the direction of a nip of a pair of withdrawal rollers over which the nonwoven fabric withdrawn from the screen drum and a subsequent funnel for

Compression and summary is fed to a sliver. Following the funnel, the compacted fibrous material is driven

Calender roller pair supplied, wherein a further compression of the now present sliver takes place.

A similar device can also be taken from the publication of EP 370340.

In the known designs special drive axles for driving the calender rolls are necessary. In addition, special guides are necessary to transfer the nonwoven fabric from the nip of the take-off rolls to the hopper with the subsequent calender rolls. In the area of these guides, it can lead to incorrect distortion in the fiber material and contamination by fiber fly. The invention now has the task of proposing a device for forming a sliver of non-woven fabric on a comber, which improves the known solutions and a compact and inexpensive device is achieved while reducing the required drive axles.

This object is achieved by proposing that the fibrous web - seen in the conveying direction - following the nip of the pair of rollers in the region of the peripheral surface of the driven roller to the hopper and the

subsequent press roll pair is transferred and one of the press rolls of the

Press roller pair rotatably and coaxially disposed on the driven roller. In this case, the press roller may be directly connected to the driven roller or fixed against rotation on the drive axle of the driven roller.

This makes it possible at least a special drive axle of the

To save Kalanderwalzenpaares because one of the calender rolls is mounted directly and coaxially on the drive shaft of the driven roller of the pair of rollers.

In addition, this ensures that the speed of the nip forming the pair of rollers and the Kalanderwalzenpaares are absolutely identical and thus false distortions are excluded. Furthermore, no additional guidance is required for the nonwoven on the way from the nip to the hopper, since the nonwoven is guided directly in the area of the peripheral surface of the driven roller.

The term "funnel" is generally to be understood as a "compaction element" in order to combine a fiber mass into a sliver, which in this case is fed to a subsequent calender roller pair for further compaction. In this case, the funnel takes over by an appropriate shape design and the task of feeding the sliver exactly the nip of the calender roll pair.

In order to support the guidance of the fiber fleece on the peripheral surface of the driven roller is further proposed that, between the nip of the

Roller pair and the funnel at least one, extending in the region of the peripheral surface of the driven roller, stationary guide means for the nonwoven fabric is arranged. For the lateral summary of the fiber fleece and the defined transfer of the combined fiber web to the hopper, an embodiment is proposed, wherein the guide means has at least one side guide which projects into the conveying path of the fiber fleece and which extends at an acute angle to the axis of rotation of the driven roller to the hopper ,

This ensures that the edge regions of the fiber fleece during

Summarize targeted and without damage to the funnel be performed. The term "guide means extending in the region of the peripheral surface" also includes those solutions in which the guide means do not exactly follow the contour of the peripheral surface of the driven roller.

To the nonwoven fabric following the nip of the rotating

To lift surface of the driven roller and for gentle transfer to the hopper, it is proposed that the guide means is provided with a lower guide surface which extends in the region of the peripheral surface of the driven roller and supports the nonwoven fabric on its underside in the transfer to the hopper.

Advantageously, it is further proposed that the hopper and the guide means are interconnected. It is advantageous if the funnel and the

Guide means are formed as a molded part of one piece.

This allows the production of a guide means with integrated funnel, wherein the guide surfaces can be optimally designed without disturbing interruptions to a gentle guidance of the fiber web. This can still be supported by the appropriate design of the surface of the guide means.

Furthermore, the one-piece molded part can be produced as a molded part made of plastic, whereby the shape is freely designable.

Preferably, the press roll mounted on the roll is secured to one end of the roll which is outside the area of the nip. Thus, the take-off area through the funnel is outside the supplied width of the fleece, whereby a complete distribution of the solder joints is possible (as well as in

Example of DE 103 00 317 A1 has been described).

Furthermore, it is proposed that the rotatably mounted press roll, which forms the press roll pair with the press roll mounted on the roll, is mounted so as to be movable transversely to its axis of rotation and is acted upon by a spring element in the direction of the press roll fastened on the roll.

By the further proposal that at least one sensor is provided which scans the movement of the movably mounted press roll, it is possible to provide a continuous monitoring of the sliver formed.

It is therefore further proposed that a control unit is provided to detect the signal output by the sensor to the control unit

Evaluate mass nonuniformity (CV value). Thus, one obtains continuously a quality feature of the formed sliver at the corresponding Kämmstelle and can, if necessary, make appropriate interventions, provided that the quality (including a missing sliver) moves from a predetermined tolerance field. Such an intervention may, for. B. include the shutdown of this Kämmstelle with a signal triggering.

The further suggestion that the press rollers are provided on their outer circumference with gear-like elevations that engage in the working position of the press rolls form-fitting, is allowed that only one of the press rolls must be driven by a drive means, while the second press roll on the gear-like elevations of the driven first press roll safely entrained, or is driven. Thus, it is also excluded that a slip occurs between the two press rolls, which could have a negative effect on the quality of the sliver.

For the gentle transport of the fiber material between the press rolls, it is proposed that the elevations have a rounded and sinusoidal shape.

Preferably, the driven roller of the roller pair one, with a

Be a vacuum source connected screen drum, which, to form a

Nonwoven fabric, combed out by a combing and tear-off fiber packets are fed discontinuously. With such a device z. B. the previously necessary Pilgerschrittbewegungen known combers are avoided as z. B. has been described in WO 2006/012758 A1.

In connection with the proposed use of a screen drum is further proposed that the combing and tear-off device consists of a nipper unit, which is associated with a combing cylinder, which on its circumference with a

Kämmsegment and a tear-off segment is provided, wherein the tear-off segment can form a nip with a deliverable tear-off.

The comber can be equipped with more than eight juxtaposed Kämmstellen, z. B. with up to 32 Kämmstellen.

Further advantages of the invention will be shown and described in more detail in subsequent embodiments.

Show it:

Fig. 1 is a schematic side view of a combing head of a comber with the invention claimed nonwoven summary.

2 shows a partial view X according to FIG. 1

Fig. 3 is an enlarged view Y of FIG. 1 without nipper unit

4 is an enlarged sectional view A-A of FIG .. 3

Fig. 4a is a partial view of FIG. 4 with a further embodiment

4b is an enlarged partial view of the Kalanderwalzenpaares of FIG. 4 with

a profiling on the outer circumference

Fig. 1 shows a schematic side view of a Kämmstelle, or a

Combing head of a combing machine, wherein for reasons of clarity on the representation of the pivot arms for the nipper unit Z, the brush roller for

Cleaning the combing cylinder 10 and the casing for the suction was dispensed with. However, this is well known and can be seen from many previous publications. In general, the comber has a variety of

adjacent Kämmstellen on. However, the embodiment is limited only to the representation of one of these Kämmstellen.

Instead of the shown pivotable attachment of the nipper unit would also be conceivable, the nipper unit (short "pliers" called) to arrange stationary, wherein to form the nip KS only the upper nipper knife 3 with respect to a fixed pliers plate 2 moves. However, this is not decisive for the proposed invention. In the present example, a reciprocating pliers Z (see double arrow) is assumed, wherein the drive for the oscillatory movement of a gear G is made, which is connected via the schematically illustrated drive path 8 with the pivot axis 4 of the frame R of the pliers Z. , Above a lower tong plate 2 is a rotatably mounted

Feed roller 5 is arranged, which is connected to an intermittent drive, not shown, and for supplying a cotton wool W (or slivers) to the clamping point KS of the forceps. In the example shown, the pliers Z is in a rear position and is closed. The end of the wadding projecting beyond the clamping point KS (fiber tuft FB) is combed out through the clothing of a combing segment 11, which extends over a partial region of the circumference of a combing cylinder 10. The combing cylinder 10 is rotatably mounted in the machine frame MS via the axis 13 and is driven by the gear G via the drive path 14 shown schematically.

The drive of the transmission G is carried out by a schematically illustrated main motor M, which communicates with a control unit ST via the line 44 in connection. On the opposite side of the combing segment 11, a tear-off segment 12 is mounted on the combing cylinder 10, which in conjunction with a displaceably mounted Abwalwalze 15 (see double arrow) the demolition of the

combed fiber tuft FB performs, as will be described below.

Adjacent to the combing cylinder 10, a sieve drum 17 is arranged, which is rotatably supported via an axis 18 via the bearings 19 and 20 in the machine frame MS, such. B. from FIG. 2 and FIG. 3 can be seen. The drive of the screen drum 17 via a drive wheel A3 (Fig. 3), which is rotatably mounted on the axis 18 and a schematically illustrated drive path AE with the transmission G in

Drive connection is (not shown).

Between the screen drum 17 and the combing cylinder 10 is one to a

Swivel axis 23 pivoting flap 22 is arranged, which has the task, depending on the position, the combed out components and the broken fiber packets to conduct accordingly. This should be avoided in particular that

combed material (noils, nits, dirt) in the area of the screen drum 17 passes. A detailed description of the function of this flap is z. B. in published WO 2008/011733 A1.

Likewise, this publication is to be taken from a corresponding embodiment of a screen drum, wherein within the screen drum still another, rotatably mounted cylinder is provided with openings to control the air flows during the Abreissund soldering process.

In the present embodiment, however, only a simple screen drum 17 is shown, in the interior of which a stationary cover element 28 is arranged, which seals off the region of the screen drum, in which the fiber web V formed on the screen drum 17 is removed from the screen drum. The interior of the screen drum 17 is connected via the line 26 to a vacuum source 25, via which a negative pressure is generated within the screen drum.

Axially parallel to the screen drum 17, a pressure roller 30 is rotatably mounted, which z. B. rests on its own weight on the circumference of the sieve drum. It can the

Pressure roller may be mounted in corresponding guides in the machine frame MS in the direction of the peripheral surface of the screen drum. Likewise, a solution is conceivable, wherein the bearing of the pressure roller is mounted in pivot arms whose pivot axes are axially parallel to the axis of the screen drum 17 and stored in the machine frame MS. The pressure roller 30 forms together with the sieve drum 17 a

Clamping point 31 for the guided between the screen drum and the pressure roller fiber web V. The nip 31 extends over the width B of the guided on the outer circumference U of the screen drum 17 nonwoven fabric V.

The pressure roller can, for. B. be provided on its outer circumference with a rubber coating and is placed on the driven screen drum 17 and the web V via friction in rotational movement.

Viewed in the conveying direction F, following the nip 31 is a

Guide member 31 is attached, via which the nonwoven fabric V (called "fleece" for short) laterally merged and to a fleece funnel 39 ("hopper" called) is discharged. In this case, the sheet-like web V is combined to form a sliver F1, which for further compression following the funnel 39 through the nip KK of a press roller pair K is guided (Fig.4). The pair of press rolls will be referred to as calender rolls K1 and K2 in the following description The guide element 31 has a lower guide surface 37 which extends over a portion of the circumference U of the screen drum 17 and, as shown in section AA (FIG. 4) is adapted to the shape of the circumference of the screen drum 17. Between the circumference U of the screen drum 17 and the guide surface 37 is only a small distance, which only ensures that the guide element 31 is not on the circumference U of the sieve drum grinds

Guide member 37 is fixed via fasteners, not shown, with the

Machine frame MS connected and thus is in a fixed position to

Peripheral surface U of the screen drum 17 is held.

For lateral guidance of the web V during the merger to the hopper 39, the guide member 33 is provided with side guides 34 and 35, which are connected to the lower guide surface 37 and extend from the latter - with respect to the axis 18 of the screening drum 17 - to the outside , These side guides 34, 35 could also be arc-shaped, as seen in cross-section, in order to support the "curling-in" of the fleece edges as far as the transfer to the hopper.

The side guide 34, on which the web V first hits after leaving the nip 31, is provided with an arc R1, which merges into a straight portion 36 which extends under a sloping winding α to the hopper 39.

The opposite side guide 35 has first a straight portion 38 which has at an angle ß with respect to the axis 18 of the drum 17, which opens into an arcuate portion R2, via which the second

Fleece edge is fed to the hopper 39. Also, the cross section of the side guide 35 may be arcuate.

In the present example, the funnel 39, the guide surface 37 and the

Side guides 34, 35 made of one piece, which z. B. from a

Plastic injection molded part can be made. The hopper 39 is provided with downwardly extending side guides 41, 42, which the lateral guidance of the im Take funnel 39 combined fiber fleece up to the nip KK a subsequent Kalanderwalzenpaares K.

In the schematic view of Fig. 4a, a partial section of Fig. 4 is shown, wherein the guide surface 37 'for the web V is not adjusted as in Fig. 4, the outer shape of the circumference of the screen cylinder 17, but at an angle δ to the tangent Tg the screening drum 17 extends and opens into the hopper 39.

Such a course, shown in FIG. 4 a, of the guide surface 37 'of the

Guide means 33 is included in the claimed term "in the region of the peripheral surface (U) of the driven roller (17) extending, stationary guide means" included.

As claimed according to the invention and shown in the example of FIG. 3, one of the calender rolls K1 of the calender roll pair K is non-rotatable and coaxial on the

Screen drum 17 is fixed and is located outside the area in which the web V with the width B in the feed to the nip 31 extends.

The second calender roll K2 is rotatably mounted via the bearing L1 in a pivot arm 49, which is mounted pivotably about a pivot axis 51 on the machine frame MS.

The pivot arm 49 and thus the calender roll K2 is in the direction of

Calender roller K1 loaded by a spring 50, which is supported on the machine frame MS. As a result, a pressure is exerted on the fiber material located in the nip KK of the calender rolls K1, K2 and this is further compressed in order to increase the adhesive force. Instead of the spring 50 shown here z. B. also a bellows cylinder can be used.

The pivoting movement of the calender roll K2 in the direction of the calender roll K1 can be limited by attaching corresponding end stops (not shown) in order to prevent complete seating of the calender roll K2 on the calender roll K1.

The movement of the swivel arm 49 is monitored by a sensor 47 fixedly attached to the machine frame MS, the signals of which are transmitted via the line 48 to the central control unit ST. In the control unit ST, these signals are evaluated on the basis of existing programs. By scanning the Pivoting movement of the pivoting lever 49, the movement of the calender roller K2 is scanned, which is caused by the mass variations of the guided through the nip KK fiber material. Thus, the mass profile in the form of a CV value can be determined and displayed. The representation can z. B. on a display AZ (eg., A screen), which is connected to the control unit ST. As soon as the determined CV value is outside the specified value

Tolerance limits moves, can be triggered via the control unit ST an additional warning light and the corresponding Kämmstelle be stopped.

The calender roll K2 is driven by a drive wheel A2, which is in drive connection with the drive wheel A1 via a belt ZR (eg toothed belt). The belt ZR is tensioned by tensioners, not shown, to compensate for the movements between the axes of the calender rolls K1, K2.

Also conceivable is the use of gear drives.

The drive wheel A2 is rotatably mounted on the axis 29, on which with the

Calender roll K2 is firmly connected. The axis 29 is, as schematically indicated, stored in the bearing point L1, which is located in the pivot arm 49.

The drive wheel A1 is mounted on the axis 18 of the screen drum 17, which also represents the drive axis of the calender roll K1, since the

Calender roller coaxial and fixed to the sieve drum 17 is connected.

Thus, an additional axis for the calender roll K1 is saved and ensures an absolute synchronization between the screen drum 17 and the calender roll K1. The axis 18 of the sieve drum 17 is on the bearings 19, 20 in

Machine frame MS rotatably mounted. Furthermore, a further drive wheel A3 is rotatably mounted on the axis 18, which has a schematically illustrated

Drive element AE with the gear G is in drive connection.

It is also a further embodiment possible, wherein the calender roll K2 not directly (as shown) via the belt transmission A1, A2 and ZR of the

driven axle 18 is actively driven, but is displaced by friction under the action of the spring load (50) of the driven calender roller K1 in rotary motion.

In the enlarged view of Fig. 4b, a further variant for the drive of the calender roll K2 is shown. The calender rolls K1 and K2 are on their Outer circumference provided with a sinusoidal profiling 54, 55, which in the operating position shown, in the field of implementation of the fiber material,

mesh like a gear. About this positive engagement of the two profilings 54, 55, the freely rotatable about the axis 18 is mounted

Calender roller K2 driven by the calender roller K1, which is in drive connection with the gear G. Ie. in this design are not special

Drive elements for the calender roll K2 necessary, as shown in the embodiment of FIG. 3. By the influence of profiling on the

performed fiber material is also still the adhesive force of the

Calender roll pair K delivered sliver F1 increased.

The function of the device shown is described in more detail below:

In the position shown in Fig. 1, the pliers Z is closed and is in a rear position. The fiber beard FB protruding from the clamping point KS of the forceps Z is replaced by the comb segment 11 of the

Combing cylinder 10 combed out. The flap 22 is located near the circumference U of the following screening drum 17, so that the combed out components (noils) are discharged downwards in a suction channel, not shown. After this

Combing the pliers Z moves in a front position and is now at a shorter distance to the tear roller 15, which has been moved in the direction of the axis 13 of the combing cylinder 10 and with the tear-off 12 a

Clamping point forms.

The tear-off segment 12 was by the rotational movement of the combing cylinder 10 during the forward movement of the pliers Z in the area below the

Tear roller 15 moves.

The end of the combed fiber tuft FB, which now protrudes from the open pliers Z, is detected by the nip between the tear-off segment 12 and the overlying tear-off roller 15, whereby the thereby detected fibers are pulled out of the end of the tuft FB, or "torn off" The fiber package resulting from this tearing process is produced under the influence of the

Screen drum 17 applied negative pressure on the end of the already resting on the circumference U of the screen drum 17 Fleece V and overlaid (soldering process) brought. Before handing over this demolished fiber packet to the

7 drum 17, the flap 22 has been moved about the pivot axis 23 in the direction of the combing cylinder 10 to assist the transfer. A detailed description of this process can, for. Example, be taken from WO 2008/011733 A1. The area of transfer, as well as the area above the screen drum 17 may be provided with corresponding shuttering (not shown) to the

To be able to precisely control air flows which are necessary for the transfer and the soldering process.

The screen drum 17 is driven at a constant speed and moves the web V on its circumference U to the nip 31 between the pressure roller 30 and the screen drum 17. After leaving the nip 31, the web V reaches the lower guide surface 37 of the guide member 33 and hits on the

Side guide 34, on which it is transferred under the action of the sheet R1 by the oblique arrangement (angle α) of the straight portion 36 to the hopper 39. The other arranged on the opposite side

Side guide 35 with its straight gate 38 (angle ß) and the bow R2 supports the transfer of the opposite web edge to the hopper 39th

The fleece transferred to the hopper 39 is thereby combined and compacted and is transferred via the hopper to the nip KK of a following and driven calender roll pair K (K1, K2). This transfer will be through the

existing side guides 41, 42 supported, which are attached to the hopper 39. This prevents lateral deflection of the fiber material before it enters the

Terminal point KK arrives, where it is further compressed. As already described, the mass fluctuations, the guided through the nip KK through

Fasergutes be detected and monitored by the pivotally mounted calender roller K2 by scanning the pivoting movement via the sensor 47.

The fiber sliver F1 delivered by the calender rolls K1, K2 downwards in the conveying direction FX reaches a conveying table T, via which it passes with further

Sliver F2 to F6, which were produced and discharged at adjacent Kämmstellen, is transferred to a subsequent drafting unit in the conveying direction FT. Subsequent to the drafting unit, a tape storage can be provided to deposit the sliver formed on the drafting unit in a pot. The table T can also be powered by a conveyor, z. B. consist of a conveyor belt. The number of transported on the conveyor table

Fiber ribbons F1 to F6 is only an example. It can also be a far larger number of combs (more than 12) arranged next to each other, which also a larger number of slivers is fed to the following drafting. Also, a number of up to 48 adjacent Kämmstellen is possible.

With the proposed device to obtain a compact and simple solution, with additional bearings and drive axles are avoided and the risk of incorrect distortion is minimized. The device proposed according to the invention is particularly advantageous for a combing machine with a large number (> 10) of adjacent combing points, in which the width of the nonwoven to be grasped is lower than is the case with conventional combing machines.

Claims

claims

1. An apparatus for forming a sliver (F1) from a, at a Kämmstelle (1) of a combing machine formed fiber fleece (V), which is a clamping point (31) of a pair of rollers (17, 30) is supplied, the one, with a drive connected roller (17) and a pressure roller (30) and - seen in the conveying direction (F) - the nonwoven fabric following the nip (31)

summarized and fed via a funnel (39) to a, with a drive (G, M) connected press roller pair (K), characterized in that the nonwoven fabric (V) - in the conveying direction (F) - seen in the following

Clamping point (31) of the roller pair (17, 30) in the region of the peripheral surface (U) of the driven roller (17) to the funnel (39) and the subsequent

Press roll pair (K) is transferred and one of the press rolls (K1) of the

Press roller pair (K) rotatably and coaxially on the driven roller (17) is arranged.

2. Device according to claim 1, characterized in that, between the

Clamping point (31) of the pair of rollers (17, 30) and the funnel at least one, in the region of the peripheral surface (U) of the driven roller (17) extending, stationary guide means (33) for the nonwoven fabric (V) is arranged.

3. Apparatus according to claim 2, characterized in that the guide means (33) has at least one side guide (34) which projects into the conveying path of the fiber fleece (V) and which at an acute angle (α) to

Rotary axis (18) of the driven roller (17) extends to the hopper (39).

4. Apparatus according to claim 3, characterized in that the guide means (33) having a lower guide surface (37) is provided, which in the region of

Peripheral surface (U) of the driven roller (17) and supports the nonwoven fabric (V) on its underside in the transfer to the hopper (39).

5. Device according to one of claims 2 to 4, characterized in that the funnel (39) and the guide means (33) are interconnected.

6. Apparatus according to claim 5, characterized in that the funnel (39) and the guide means (33) is formed as a one-piece molded part.

7. Device according to one of claims 1 to 6, characterized in that on the roller (17) fixed to the press roller (K1) is attached to one end of the roller (17) which is located outside the region of the clamping point (31).

8. Device according to one of claims 1 to 6, characterized in that the rotatably mounted pressure roller (K2), which with the, on the roller (17) attached to the press roller (K1) forms the press roller pair (K), transversely to its axis of rotation ( 18) is movably mounted and via a spring element (50) in the direction of the roller (17) fixed to the press roller (K1) is acted upon.

9. Apparatus according to claim 8, characterized in that at least one

Sensor (47) is provided, which scans the movement of the movably mounted press roller (K2).

10. The device according to claim 9, characterized in that a control unit (ST) is provided to evaluate the output from the sensor (47) to the control unit signal for determining mass irregularity (CV value).

11. Device according to one of claims 8 to 10, characterized in that the press rollers (K1, K2) are provided on its outer circumference with gear-like elevations, which engage positively in the working position of the press rollers.

12. The device according to claim 11, characterized in that the elevations have a rounded and sinusoidal shape.

13. Device according to one of claims 1 to 4, characterized in that the driven roller (17) of the roller pair (17, 30) one, with a

Vacuum source (25) connected to the screening drum (17), which, for forming a nonwoven fabric (V), by a combing and tear-off device (Z, 10, 15)

combed fiber packets are fed discontinuously.

14. The apparatus according to claim 13, characterized in that the combing and tear-off device (Z, 10, 15) consists of a nipper unit (Z), which is assigned a combing cylinder (10) having on its circumference with a

Combing segment (11) and a tear-off segment (12) is provided, wherein the

Abreisssegment (12) with an undeliverable tear-off roller (15) can form a nip.