WO2008110137A1

WO2008110137A1 - Device having a stretching unit for processing fibrous material

Info

Publication number: WO2008110137A1
Application number: PCT/DE2008/000359
Authority: WO
Inventors: Wolfgang Bauer; Axel Flad
Original assignee: Sipra Patententwicklungs- Und Beteiligungsgesellschaft Mbh
Priority date: 2007-03-15
Filing date: 2008-03-03
Publication date: 2008-09-18
Also published as: DE102007013109A1

Abstract

The invention relates to a device for processing fibrous material (2) having at least one stretching unit and one thread-producing element (17a) defining a feed surface (22) for the fibrous material (2) subsequent thereto. The stretching unit has a first single- or double-apron roller pair (5a, 6a to 9a, 10a) defining an apron surface (21) and a second delivery roller pair disposed between said first roller pair and the thread-producing element (17a), said second roller pair having a lower roller (12a) and an upper roller (14a) forming a pinch line (23) with said lower roller and having a rotational axis (25a). According to the invention, the feed surface (22) and the apron surface (21) are each disposed at a pre-selected distance (x, y) from the pinch line (23) between the respective surface and the rotational axis (25a) of the upper roller.

Description

DEVICE WITH RANGE FOR PROCESSING FIBER MATERIAL

The invention relates to a device of the type specified in the preamble of claim 1.

Devices of this type (for example DE 38 10 846 A1, DE 103 11 826 A1) are used in spinning technology for the production of a spun yarn from a staple fiber bandage, which can be present as a band, sliver, roving or the like. The drafting system is required for refinement of the fiber material, while the yarn formation element following the drafting system serves the purpose of giving the desired rotations to the fiber material emerging from the drafting system.

The speeds of the output rollers of the drafting systems are at least partially extremely high. While the delivery rollers in conventional ring spinning operate at delivery speeds of only about 20 m / min and in centrifuge spinning at delivery speeds of about 80 m / min, high-performance spinning, spinning and friction spinning (eg PCT WO 2004/079068) are used. Drawframes needed, with their output rollers delivery speeds of about 250 m / min to 700 m / min can be achieved.

In the operation of such drafting systems often occur undesirable effects in the range of the output rollers. These include especially winding formations on the output rollers and on the roll surfaces resulting deposits, the z. B. caused by electrostatic charging of the fibers, by sticky components and by dirt particles in the fibers and / or by fibers separated from the fiber structure. These effects are also noticeable on the upper output rollers, since they are usually provided with a cover made of a rubber-elastic material.

To avoid these effects, numerous proposals are already known. These usually provide suction devices associated with the top rollers, which are brought closer or closer to the roller surfaces iz ^ JJJQE. JÖ = 3 * 7 ~ Θ6 | 6 Al) and with On the roll surfaces resting scrapers (DE 100 50 974 Al) can be combined.

For high-performance drafting systems such cleaning devices are not sufficient. One reason for this seems to be that the lower outfeed rollers made of steel are usually provided with a peripheral surface having a corrugation. At high speeds, this corrugation acts like a pump which circulates particles appearing in the exit slit of the delivery rolls together with the air and returns them to the entry slit of the delivery rolls. As a result, not only an increased fiber loss is effected and a winding is promoted on the lower roller, but it is also a uniform-fiber entry into the nip of the output rollers additionally hindered. These undesirable effects can not be avoided by the described cleaning devices alone. This also applies if directly following the nip line of the delivery rollers there follows a mechanical, vacuum-operated or otherwise operating yarn formation element which exerts a certain suction effect on the fiber material in the direction of its intake plane.

Proceeding from this, the technical problem of the invention is to design the device of the type described above so that the fiber losses in the range of the output rollers and the adverse effects of the pumping action of the lower rollers stronger than previously avoided and a cheaper even in their application in high-performance drafting Fiber guide is achieved.

A solution to this problem is provided by the characterizing features of claim 1.

The invention is based on the idea of directing the flow of the fiber material by an offset of the infeed and apron plane relative to the nip line of the exit rollers such that fibers appearing in the exit nip of the exit rollers or the like are preferably fed directly to the yarn formation element despite the pumping action of the bottom roller or at most be taken by the top roller. However, since their peripheral surface is smooth, the effects described here have less effect. Any accumulations of fibers or dirt particles, as well as fiber entanglements on the top rollers can be further reduced if necessary by the additional application of known suction.

Further advantageous features of the invention will become apparent from the dependent claims.

The invention will be explained in more detail below in connection with the accompanying drawings of an embodiment. Show it:

1 shows a perspective view of a device according to the invention for processing fibers with two drafting devices and yarn-forming elements;

FIG. 2 shows a schematic side view of the device according to FIG. 1 in the region of the exit rollers; FIG. and

Fig. 3 shows schematically the relative position of different parts of the device according to FIGS. 1 and 2.

Fig. 1 shows a classic 3-roller drafting system, which in a direction indicated by arrows 1 transport direction only schematically illustrated, z. B. promotes fibrous material 2 formed as a band or roving. For this purpose, the drafting system has three pairs I, II and III of drafting device bodies arranged one behind the other in the transport direction.

The first pair I includes two rollers 3a and 4a as drafting device.

The second pair II is designed as Doppelriemchen- pair of rollers and contains as drafting organs depending on a roller 5a and 6a, depending in the transport direction behind these rollers 5a, 6a lying, also referred to as turning rail, consisting mostly of a stationary rod deflecting element 7a and 8a and je a via the associated rollers 5a, 6a and deflecting elements 7a, 8a guided straps 9a and 10a. The straps 9a, 10a serve the purpose of guiding the fiber material 2 after leaving the rollers 5a, 6a up to an outlet gap 11, which usually has an adjustable jaw width. The strap 9a may also be passed over an unillustrated tensioning element to provide it with a desired preload on the roller 5a and - A -

Hold deflecting element 7a.

The third pair III contains, analogously to the first pair I, two rollers 12a and 14a as drafting device elements. 5

The described rollers 3a to 6a and 12a, 14a of the three pairs I, II and III of drafting device form between them usual nip lines. Moreover, the pairs I and II form a Vorverzugszone by the peripheral speeds of the rollers 3a, 4a and 5a, 6a are selected such that z. B. a distortion of the fiber material 2 between 5- 10 and 15-fold is obtained. In contrast, the fiber material 2 is subjected to a main delay between the pairs II and III, which leads to an extension of the fiber material 2 z. B. by 50 times or more and thereby leads to a desired final fineness at the exit of the rollers 12a and 14a.

15 The storage and the drive of the roller pairs I to III can be done in the usual way. For example, the rollers 3a, 5a and 12a are forcibly driven in a manner known per se. Serve not shown, mounted on their shafts gears od. Like. And coupled with these drive motors. On the other hand, the rollers 4a, 6a and 14a are supported by friction only by the rollers 3a, 5a and 12a.

20 taken by, as usual, on a only schematically shown in Fig. 2

Druckarm 15 od. Like. Are rotatably mounted od with a bearing axis on a stationary frame. The like. Swivel mounted and with the help of a force, eg. B. a spring force, is pressed against the rollers 3a, 5a and 12a. On the same pressure arm 15 and the deflecting element 8a is mounted so that this and thus a lower strand of the strap

25 10a is pressed against an upper run of the strap 9a. For this purpose, the deflecting element 8a may be part of a conventional apron cage.

Due to the apparent from Fig. 1 arrangement forcibly driven, ie the driving rollers 3a, 5a and 12a are usually referred to as bottom rollers and taken by these 30 by friction, driven rollers 4a, 6a and 14a as top rollers. Accordingly, the strap 9a is a bottom strap and the strap 10a is a top strap. As a result, the same terms are used in the following description, although in principle also the driving draft organs above and the driven drafting devices could be down.

1 shows that a preferred drafting arrangement at least on one side, but preferably on both sides of a stationary bearing block 16 or a corresponding frame, frame or housing part contains at least two, substantially according to FIG. 1 formed drafting, their drafting organs are denoted by the reference numerals 4a to 14a and 4b to 14b. In particular, in the case of spinning knitting, the drafting system members 4a, 4b to 14a, 14b are preferably mounted on a common shaft or rod, depending on their function, which are flying, i.e. H. is only rotatably mounted at one end or fixedly mounted in the bearing block 16. As a result, the respective other ends or rods are exposed, so that the various parts, in particular the straps 9a, 10a are easily accessible from the outside and therefore can also be easily replaced.

Finally, FIG. 1 shows that a drafting element 17a, 17b is assigned to each drafting system. The Garnbildungselemente 17 a, 17 b included in the embodiment depending on a pneumatically operating swirl member 18 a, 18 b and a downstream of this Führungsbzw. Transport tube 19a and 19b. The twist elements 18a, 18b serve z. B. the purpose of sucking or deduct from the exit slits of the output rollers 12a, 14a and 12b, 14b exiting fiber materials 2, rotate and thereby transform into a temporary yarn passing through the transport tube 19a, 19b through z. A knitting machine (e.g., PCT WO 2004/079068). Alternatively, the Garnbildungselement 17a, 17b but also from any other, mechanically, pneumatically or otherwise operated device to produce in the usual manner in spinning machines a spun yarn or a knitting or the like. Suitable, temporary yarn, prior to the stitch formation is reverted back to a substantially untwisted yarn due to the false-twist effect.

Devices of the type described are generally known from the documents mentioned above, which is why they are hereby made to avoid repetition by reference to them the subject of the present disclosure.

The device with the drafting device organs 3a to 14a and the Garnbildungselement 17a is substantially identical to the device formed with the drafting system members 4b to 14b and the yarn formation member 17b. The invention will therefore be described below only with reference to the device having the parts marked with the letter "a".

As shown particularly in FIG. 2, the two straps 9a, 10a define therebetween a strapping plane 21. This is the plane along which the fiber material 2 in the transport restraint 1 is guided through the pair of double-belt rolls. The Garnbildungselement 17a defines a feed plane 22 (or a feed axis). This is the plane or axis along which the fiber material 2 leaving the delivery rollers 12a, 14a is fed mechanically, pneumatically or otherwise into the yarn formation element 17a. Finally, the two output rollers 12a, 14a between them form a nip line 23. As a rule, the Riemchenebene 21 and the feed plane 22 are coplanar and parallel to the transport direction 1 and parallel to axes of rotation 24a, 25a of the output rollers 12a, 14a extends, while the nip line 23 parallel is arranged to the axes of rotation 24a, 25a. However, solutions are also known in which the feed plane 22 is arranged obliquely to the apron plane 21.

According to the invention, as indicated enlarged in FIG. 3, the intake plane 22 is at a preselected vertical distance x and the apron plane 21 is at a preselected vertical distance y _. from the nip line 23 and further to be arranged so that both planes 21, 22 between the nip line 23 and the axis of rotation 25 a of the upper output roller 14 a are extended. Both the feed plane 22 and the Riemchenebene 21 is preferably skewed to the nip line 23 extends. As a result, according to FIG. 2, on the one hand, it is achieved that the straps 9a, 10a leave

Fiber material 12 occurs at a location 26 on the peripheral surface of the upper output roller 14a, which is above the nip line 23 and above the outer contour of the lower output roller 12a. On the other hand, at a position 27, the fiber material 2 is separated from the upper exit roller 14a and drawn into the feed opening of the yarn formation element 17a, which is above the nip line 23 and the outer contour of the lower exit roller 12a. This has the result according to the invention that an approximately forming fiber winding is preferably placed around the top roller 14a and not around the bottom roller 12a and in the transport direction 1 behind the nip 23 emerging loose fibers, Also, if the peripheral surface of the upper roller 14a is smooth and the peripheral surface of the lower roller 14b is provided with the usual corrugation, dirt particles, etc. are also preferentially entrained by the upper roller 14a. In addition, the advantage is achieved that less loose fibers circulate with the upper roller 14a, ie, the proportion of the fibers formed by the Garnbildelement 17a is increased.

In a presently considered best mode, the distance x is less than the distance y. Particularly suitable values for x and y and the ratio x to y currently appear to be at x = 0.5 mm to 2 mm and at y_ = 1.5 mm to 5 mm and can be determined in individual cases by experiments.

According to a preferred embodiment of the invention, the upper output rollers 14a, 14b are additionally assigned a respective suction device 28a, 28b. These contain z. Curved tubes connected at one end to a source of vacuum, not shown, and disposed at the other end in any convenient manner close to the outer peripheral surface of the upper exit rollers 14a, 14b. These preferably additionally present suction devices 28a, 28b serve, on the one hand, to suck off particles of all kinds entrained by the upper exit rollers 14a, 14b and to keep them away from the area of action of the entry gap between the exit rollers 12a, 14a or 12b, 14b. On the other hand, it is avoided by the suction devices 28a, 28b that circulating air leads to turbulence in the entrance slits of the exit rollers 12a, 14a or 12b, 14b. Both ensure that a uniform fiber entry into the nip lines 23 is possible. The negative pressure in the suction devices 28a, 28b can for this purpose z. B. 10 mbar to 20 mbar below the outside pressure.

Further, it is expedient to offset the axis of rotation 24a of the lower output roller 12a in the transport direction 1 relative to the axis of rotation 25a of the upper output roller 14a, in particular to arrange behind this, as indicated in Fig. 2 by a measure z. This makes it possible, in particular, to offset the deflecting elements 7a, 8a according to FIG. 2 with a corresponding distance in the transport direction 1 and thereby guide the fiber material 2 leaving the straps 9a, 10a tightly against the circumferential surface of the top roller 14a. The device according to the invention is preferably used on drafting devices whose output rollers 12a, 14a and 12b, 14b deliver the fiber material 2 at conveying speeds of 100 m / min and more. However, this does not exclude that the device can be successfully applied to drafting systems with lower output speeds.

The invention is not limited to the described embodiment, which can be modified in many ways. As already mentioned, the term "lower" or "upper" output roll 12a, 14a is in principle arbitrary, i. H. In the context of the invention, the upper output roller 14a could also be arranged laterally next to the output roller 12a by pivoting the drafting system through 180 ° also below or by pivoting the drafting system by 90 °. Other arrangements are possible in this context. It is also clear that instead of Doppelriemchen pair II of drafting system organs and a Einriemchen pair II could be provided by z. B. the strap 7a or 8a is omitted. Further, the invention can also be realized from a drafting system with more or less than the three illustrated roller pairs I to III. In addition, it would be possible to arrange the feed plane 22 or axis obliquely to the apron plane 21 and also provide the distance x to the nip line 23 in this case. Finally, it is understood that the various features may be applied in combinations other than those illustrated and described.

Claims

Claims(

1. An apparatus for processing fiber material (2) having at least one drafting device and a yarn formation element (17a) following thereon, a feed plane (22) for the fiber material (2), the drafting system having a first, a surface plane (21). single or double belt roller pair (Sa, 6a to 9a,

10a) and a second, between this and the Garnbildungselement (17a) arranged pair of output rollers, which comprises a lower roller (12a) and with this a nip (23) forming, a rotation axis (2Sa) having upper roller (14a), characterized in that the pull-in plane (22) and the apron plane (21) are each arranged at a preselected distance (x, yj from the nip line (23) between the latter and the top roller rotation axis (2Sa).

2. Apparatus according to claim 1, characterized in that the distance 00 between the feed plane (22) and the nip line (23) is smaller than the distance (y_) between the Riemchenebene (21) and the nip line (23).

3. Apparatus according to claim 1 or 2, characterized in that the upper roller (14a) is associated with a suction device (28a).

4. Device according to one of claims 1 to 3, characterized in that the lower roller (12 a) has a rotation axis (24 a), in a transport direction (1) of the

Fiber material (2) behind the top roller rotation axis (25a) is arranged.

5. Apparatus according to claim 4, characterized in that the first pair of rollers as a respective Unterriemchen (9a) and a Oberriemchen (10a) exhibiting Doppelriemchen- roller pair is formed.

6. The device according to claim 5, characterized in that the straps (9a, 10a) via deflecting elements (7a, 8a) are guided and a deflecting element (7a) for the Unterriemchen (9a) in the transport direction (1) of the fiber material (2) behind a deflecting element (8a) for the top apron (10a) is arranged.

ADJUSTED SHEET (RULE 91) ISA / EP