EP1092794B1 - Yarn draw-off nozzle for an open-end spinning machine - Google Patents

Description

The invention relates to an open-end rotor spinning device the preamble of claim 1.

When manufacturing yarns using the OE rotor spinning process the yarn is drawn from the inside of the rotor via the discharge nozzle deducted. The rotation of the rotor turns Yarn legs and gives the yarn a real twist (Real wire). In addition, due to the slip Rolling movement of the yarn over the surface of the take-off nozzle creates a rectified temporary rotation (false wire). By increasing the false wire, the spinning stability be improved in the OE rotor spinning process. Both Rotational parts plant according to the principle of Twist compensation in tensioned threads against the Thread take-off direction in the thread into the rotor groove and let the integration zone arise there.

The length of the embedding zone affects the formation of Wrapping fibers or so-called abdominal bandages. Wrapping fibers are individual fibers that are not or are incompletely screwed into the thread core and then in changing direction of rotation partly loose, partly very firm, around the yarn periphery. Due to an increased false wire more and more wrapping fibers are formed, the formation such belly bandages also take place unevenly. Thereby the yarn structure suffers and the area of application for OE rotor yarns is restricted.

From DE 39 34 166 A1 it is known to produce yarn by appropriate training of the discharge nozzle with regard to Influencing spin stability and hairiness while doing so to influence the false wire formation. The one from the rotor pulled thread rolls over the surface of the Mouth funnel of the thread take-off channel and learns a false wire. This false wire formation is in each case and after essentially passing in Notches running in the thread take-off direction are reduced. The thread is always in the deflection area with the surface of the extraction nozzle at least partially in contact. Exactly in the middle between two Notches arranged should have good spinning stability at the same time have the effect of roughening the thread. On regular alternating contact of the thread between notch and A head start should allow stable spinning on the one hand and on the other hand effect the desired hairy yarn. The yarn is plucked and thereby brought into a hairy state. The hairiness arises in part from the fact that outer is not quite fibers embedded in the thread partly from the thread assembly be solved and stand out. The notches or grooves set the thread in vibration. The thread vibrations continue into the rotor groove and influence the Spinning stability, the yarn structure and the yarn quality.

DE 36 34 567 A1 discloses a device for removing the Yarns from the fiber collection groove of the rotor of an open-end rotor spinning device. The surface of the fiber take-off nozzle which rolls the yarn smoothly, points in the circumferential direction Sectors in which the coefficient of friction is lower than in the other sectors or in the remaining sector. By the lower friction the yarn gets less false wire issued as outside the fiber feed zone. The Fiber feed zone is usually due to the location of the Fiber guide channel and its mouth determined. The false wire is given to the yarn at the take-off nozzle. The wrapping fibers respectively so-called abdominal bandages are formed preferably in the binding zone, i.e. in the rotor groove or in the fiber feed zone. The sector with the local change in the coefficient of friction between yarn and Extraction nozzle surface is thus to the location of the fiber feed positioned that the reduction in false wire formation at Passing the yarn through the fiber feed zone in the Rotor groove takes place.

The point of detachment of the thread from the rotor groove is the point where the thread is most stressed when it is pulled off. The piece of thread between the rotor groove and that through the take-off nozzle caused by the false wire with a higher rotation than is caused by the Rotor rotation results. The one brought in at the detachment point increased rotation improves spinning stability. Maintaining false wire formation is therefore usually desired.

The invention is based, which Reduce the likelihood of undesired formation of a lower abdomen.

This object is achieved by a Rotor spinning device with the features of claim 1 solved.

Advantageous embodiments of the invention are the subject of Dependent claims.

The thread take-off nozzle of the open-end rotor spinning device according to the invention has one in the circumferential direction of the thread abruptly offset depression, its depth and course in Circumferential direction of the thread take-off nozzle is designed so that the Thread essentially over the entire deflection distance in Draw-off direction of the thread and over an angular range α Thread take-off nozzle of at least 10 degrees in contact with Thread take-off nozzle loses. This thread take-off nozzle does not work only a controllable complete interruption of the False wire formation, but even a removal of the im Legs of false wire present. Simultaneously with that Falling the false wire torque collapses the thread tension of the rotating yarn leg to almost zero. The Removing the false wire works in the short period surprisingly, as experiments have shown, not disadvantageous on the spinning stability.

The fibers accumulated in the rotor groove go in one zone before the detachment point from the untwisted one in the fiber accumulation Layer over into a rotated position. This transition zone is called Inclusion zone designated. Passes the yarn and thus the Inclusion zone the area of the fiber feed into the rotor groove and if the staple fibers are integrated at this point, it increases the likelihood of wrapping fibers. The Embedding zone can be with an inventive Thread take-off nozzle to such an extent at the location of the Fiber feed into the rotor groove will shorten the formation of wrapping fibers or lower thirds can be reduced. The interruption of contact leads to a short - term change or reduction of the Twist in the twine leg and a displacement of the Force balance between yarn twist and Section modulus in the rotor groove without the spinning stability to adversely affect.

With this open-end rotor spinning device you can simple and reproducible way a considerable desired change in the structure of the yarn and thus a Expansion of the field of application of the spun rotor yarns to reach.

The angular range in the circumferential direction of the thread take-off nozzle and hence the period in which the contact between the current Thread and the surface of the thread take-off nozzle in the deflection area of the thread is broken and in which no further False wire is generated lies in the invention Form the thread take-off nozzle in sufficient size to an effective reduction of the increased twist in the twine leg between the rotor groove and the thread take-off nozzle. There the processes run in very short periods of time, also practice the Mass inertia and the elastic properties of the thread when the rotation compensation and the shortening of the Inclusion zone still have a delaying influence. at execution of the thread take-off nozzle according to the invention is during the interruption of contact the process of rotation compensation and the integration zone shortening is neither interrupted nor disturbed.

There are subclaims for training the deepening directed, improvements are achieved in that a complete removal of the thread from the surface of the Thread take-off nozzle as quickly as possible, suddenly and over one takes a long time and the thread does not hit unwanted disturbances. It's an abrupt deposition forming side surface of the recess and the surface of the Thread take-off nozzle form an edge on which the thread of the contour the surface of the thread take-off nozzle in its movement can follow and from the surface of the thread take-off nozzle solves. The shape of the edge can be designed such that a Undercut is formed. Adjusting the course of the Edge to the curvature of the twine rope curve of the twine leg enables a largely simultaneous detachment of the thread from the surface, avoiding a delay in entry the complete interruption of contact. With the constructive Execution of the recess, for example with a convex Formation of the shape of the side surface can affect the desired yarn structure, the yarn parameters and the textile Final articles are taken.

A thread take-off nozzle, in which the each during the Spinning process fixed angular position of the recess, based on the mouth of the fiber guide channel is changeable universal use and the position of the recess Lot change according to the changed spinning conditions to adjust.

Alternatively, use thread take-off nozzles when inserting inevitably assume a predetermined position, a change of Thread take-off nozzle with an adaptation to the respective Spinning conditions can be carried out quickly, precisely and safely.

A thread take-off nozzle made of a ceramic material ensures the preservation of the shape, especially the edge, and thus maintaining the desired effect over you extremely long period.

Yarns spun with thread take-off nozzles according to the invention in addition to the significantly reduced Number of winding fibers a significantly changed loose Yarn structure. The other characteristics of these threads are similar those of yarns spun with a smooth take-off nozzle were. Restrictions on the use of rotor yarns compared to ring yarns, which are caused by the fact that usual Rotor yarns are harder to handle, significantly less hairiness are effectively counteracted. The easy one Rather, the yarn structure opens up the rotor yarns spun in this way new areas of application, in which preferably voluminous and soft yarns are processed.

Further details of the invention are based on the Representation of the figures explained.

Fig. 1

die vereinfachte Teilansicht einer Offenend-Rotorspinnvorrichtung mit einer Fadenabzugsdüse, teilweise im Schnitt,

Fig. 2

eine Prinzipdarstellung der Fadenbildung im OE-Spinnrotor,

Fig. 3

den OE-Spinnrotor und die Fadenabzugsdüse, entsprechend Ansicht A der Figur 1 teilweise im Schnitt,

Fig. 4

die Fadenabzugsdüse entsprechend der Ansicht B der Figur 1,

Fig. 5

die Fadenabzugsdüse der Figur 4 im Schnitt C-C,

Fig. 6

die Fadenabzugsdüse entsprechend der Ansicht D der Figur 4,

Fig. 7

die in Einzelheit E der Figur 6 gezeigte Vertiefung im Schnitt,

Fig. 8 - 13

vereinfachte Darstellungen von weiteren Varianten der Vertiefung neben der in Figur 7 gezeigten Ausbildung,

Fig. 14

eine schematische Darstellung einer der Krümmung des Garnschenkels angepaßten Kante der Vertiefung.

It shows:

Fig. 1

the simplified partial view of an open-end rotor spinning device with a thread take-off nozzle, partly in section,

Fig. 2

a schematic representation of the thread formation in the OE spinning rotor,

Fig. 3

the OE spinning rotor and the thread take-off nozzle, according to view A of Figure 1, partly in section,

Fig. 4

the thread take-off nozzle according to view B of Figure 1,

Fig. 5

the thread take-off nozzle of Figure 4 in section CC,

Fig. 6

the thread take-off nozzle according to view D of Figure 4,

Fig. 7

the recess shown in detail E of Figure 6 in section,

Figures 8-13

simplified representations of further variants of the recess in addition to the design shown in FIG. 7,

Fig. 14

is a schematic representation of an edge of the recess adapted to the curvature of the yarn leg.

The spinning rotor 1 shown in FIG. 1 has a shaft 2. Its axis of rotation is 3, the rotor groove is 4 and the Fiber sliding surface in the interior of the spinning rotor 1 designated 5. The rotor cover 6 has a fiber guide channel 7, the Mouth 8 is directed to the fiber sliding surface 5. The in the Rotor groove 4 fibers are collected as thread 9 through the the rotor cover 6 attached thread take-off nozzle 10 and that Thread take-off tube 11 by means of a take-off device 12 which has a pair of take-off rollers 13, 14.

FIG. 2 shows a further explanation of the spinning process a schematic diagram of the open-end rotor spinning device in perspective view. The separated fibers 15 are through the fiber guide channel 7 into the interior of the spinning rotor 1 transported and occur at the mouth 8 of the fiber guide channel 7 onto the fiber sliding surface 5 of the spinning rotor 1. To the way to better illustrate the fibers 15 are part of the Open-ended rotor spinning device in Figure 2 transparent shown. The fibers 15 lie largely stretched on the Fiber sliding surface 5 and migrate through the action of Centrifugal force into the rotor groove 4, where it is a form annular fiber accumulation 16. The developing Thread 9 is between the rotating spinning rotor 1, which as rotatable thread clamp acts, and the pair of draw rollers 13, 14, that acts as a nip, a rotation, a so-called Real wire, granted. The between the take-off rollers 13, 14 pinched thread 9 is at the thread take-off nozzle 10 by about 90 ° diverted. The angled piece of thread, the so-called Yarn leg 17 runs through the rotation of the spinning rotor 1 in Direction of rotation 18 of the spinning rotor 1. Pull the Draw-off rollers 13, 14 the thread 9, as usual, with a constant Speed from the spinning rotor 1, a condition arises a, in which the section of thread 9 between the Draw-off rollers 13, 14 and the detachment point 19 of the thread 9 from the Rotor groove 4 is given a constant rotation. In the Embedding zone 20, which is adjacent to the separation point 19 in the Rotor groove 4 lies, the fibers 15 go out of the untwisted Position in the fiber accumulation 16 in a rotated position. At the Detachment point 19 at which the thread 9 emerges from the rotor groove 4 is withdrawn, the thread 9 must have so much strength and so have a lot of twist so that it doesn't tear. The rotation on Detachment point 19 can be due to false wire, which is caused by the unrolling of the yarn leg 17 on the surface of the thread take-off nozzle 10 arises, be increased.

By pulling the thread 9 out of the spinning rotor 1 the separation point 19 moves in the same direction as that Direction of rotation 18 of the spinning rotor 1. The length of the Embedding zone 20 depends, for example, on what yarn twist and which rotor speed is specified and how high the False wire is.

The exemplary embodiment in FIG. 3 shows a view in the direction of the rotor interior. A rotor of the type S 246 BD from the applicant is used as spinning rotor 1 at a speed of n = 63,000. The fiber slip range β is 65 degrees. The fiber slip range β is the angular range between the point of the fiber feed 21 in the spinning rotor and the point of the fiber feed 22 in the rotor groove 4. In the exemplary embodiment, cotton yarns are spun with a fineness T _t yarn = 30 tex. Other spinning parameters are: fiber material 100% CO sliver count 3.42 ktex Spinning vacuum 75 mbar delay 114 A thread draw-off nozzle 10 is used, as shown in FIGS. 4 to 6. The thread draw-off nozzle 10 has a recess 24 on its surface facing the spinning rotor 1, the stepped side surface 25 of which falls abruptly at an angle of 90 ° to the surface in the yarn circulation direction and a flatly rising side surface 26 forms a recess 24. The side surface 26 rises in the yarn circulation direction at an angle γ of 20.5 degrees. The thread draw-off nozzle 10 has an external thread 28 through which the thread draw-off nozzle 10 is rotatably introduced into an internal thread of the rotor cover 6, which thread thread is not shown for reasons of simplification. The distance a, designated 29, between the edge 30 and the deepest point 31 in the base of the depression 24 is 1.5 mm in the exemplary embodiment.

The through the yarn guide channel 32 of the thread take-off nozzle 10 drawn thread 9 runs with its yarn leg 17 in Direction of rotation 18 and crosses the with each revolution Edge 30. At the edge 30, the thread 9 in its Fig. 7 dash-dotted movement of the contour of Surface of the thread take-off nozzle 10 does not follow and loses the Contact to the surface in an angular range α of 25 °. The Thread 9 is again in contact with the point of impact 34 Surface of the thread take-off nozzle 10. During the Contact interruption is followed by a complete interruption the false wire formation in the section of thread 9 between Detachment point 19 and the take-off rollers 13, 14. Simultaneously the thread tension of the rotating yarn leg 17 collapses to almost zero. There is a rotation compensation within this thread section instead, through which the separation point 19 applied torque is significantly reduced. The Lower torque has the result that the binding zone 20 is shortened.

Among those applicable to the embodiment Spinning conditions have shown that the embedding zone 20 at Place the fiber feed 21 in the rotor groove 4 then on Minimum is reduced if the position of the edge 30, that is Start of the recess 24, in the yarn circulation direction by one Angle δ of 65 ° counterclockwise to the location of the point the fiber feed 21 and thus the location of the mouth 8 of the Fiber channel 7 is offset.

The minimized integration zone 20 occurs in the exemplary embodiment then when the circumferential leg of yarn 17 the Fiber feed 22 happens. This will form Winding fibers significantly reduced; the yarn will ringgarnähnlicher. In conjunction with the through the Contact interruption introduced thread tension vibrations the yarn structure becomes looser and the production of textiles Allows end products with a softer grip. With the dash-dotted yarn legs 17 'is indicated that outside the zone of the fiber feed 22 into the rotor groove 4 there is a much longer integration zone 20 '. Through the described execution of the recess 24 arises about the circumference of the spinning rotor 1 varies greatly in length Embedding zone 20, 20 'in the area of fiber binding 22 in the rotor groove 4 is many times shorter than that on the remaining scope. This will on the one hand Wound fiber formation suppressed, and on the other hand there is one sufficiently high spinning stability.

Figures 8 to 13 show in a highly simplified representation different variants of a recess 24. The angular position of the Side surfaces 25 and 26 can in the illustrated alternative designs vary. The shape of the Side surface 26 can be convex. The edges 30 of the Level can be burr or burr-free, sharply broken or with be rounded to a radius. The bottom of the recess 24 can be rounded or edged by a transition.

14 shows a thread take-off nozzle 10 with a stepped edge 36, the course of the curvature of the Yarn rope curve of the rotating in direction of rotation 18 Twine leg 17 is adapted. The course of the yarn leg 17 forms between the detachment point 19 and the yarn guide channel 32 depends on the spinning settings and from the fiber raw material. By the the yarn rope curve of the Yarn leg 17 designed to run the edge 36 the yarn leg 17 suddenly loses and at the same time Contact with the surface of the thread take-off nozzle 10. The Rotation compensation can be done without delay and undisturbed.

With the thread take-off nozzles 10 according to the invention, the thread 9 can be lifted from the surface of the thread take-off nozzle 10 for a limited time and can be predetermined locally. The thread take-off nozzle 10 is designed such that the recess 24 extends into the mouth opening or the yarn guide channel 32 of the thread take-off nozzle 10. The false wire formation is completely interrupted each time the recess 24 is covered. At the same time, the twist build-up on the surface of the thread draw-off nozzle 10 is released, and the thread pull force collapses to values up to F _min = 10 cN. These changed spinning conditions lead to a short-term decrease in the twist distribution in the yarn, as a result of which the balance of forces between the twist and the moment of resistance in the rotor groove is shifted. The thread tension vibrations induced by the collapse of the thread tension are very short and high-frequency and do not adversely affect the spinning stability.

Is the recess 24 or the area of the Contact break positioned so that minimized Binding zone 20 is generated when the thread passes the area passes the fiber feed 22, the formation of Lower thirds significantly suppressed, and the yarns have one loose yarn structure with significantly reduced Number of winding fibers. The yarns have yarn values with those of yarns with a smooth thread take-off nozzle have been spun, are comparable, but can be very be a lot hairier. The open yarn structure with other similar ones Yarn parameters enable new ones for rotor yarns Areas of application in which preferably voluminous and soft Yarns are processed.

Claims (10)

1. Open-end rotor spinning arrangement comprising a yarn withdrawal nozzle (10) via which the yarn (9) is taken off from its tying up zone (20, 20') within the spinning rotor (1) and during rotation on the yarn withdrawal nozzle (10) is deflected in a rolling and sliding manner with additional formation of a false twist, the yarn withdrawal nozzle (10) comprising a means which brings about a reduction in the false twist within a zone extending over a circumferential portion of the yarn withdrawal nozzle (10) and the means and the mouth (8) of a fibre guide conduit (7) being arranged with respect to each other in the spinning rotor (1) in the rotational direction (18) of the rotor for feeding (21) of the fibres in such a way that the yarn (9), when passing the feed region (22) of the fibres into the rotor groove, is subjected to the influence of false twist with a reduced yarn twist, characterised in that the means is formed by a depression (24) abruptly offset in the rotational direction of the yarn (9), of which the depth and extent in the circumferential direction of the yarn withdrawal nozzle (10) is such that the yarn (9) substantially loses contact with the yarn withdrawal nozzle (10) over the entire deflection distance in the direction of take-off of the yarn (9) and over an angular extent α of at least 10°.
2. Open-end rotor spinning arrangement according to claim 1, characterised in that the depression (24) is asymmetrical, the first lateral face (25) of the depression brushed over by the yarn limb falling away so steeply, viewed in the rotational direction of the yarn, that the yarn (9) cannot follow the contour of the surface of the yarn withdrawal nozzle (10) in its movement and the lateral face (26) of the depression (24) following in the rotational direction of the yarn rises in a considerably flatter manner compared to the first lateral face (25).
3. Open-end rotor spinning arrangement according to claim 1 or 2, characterised in that the depression (24) is constructed as a substantially radially extending step.
4. Open-end rotor spinning arrangement according to any of the preceding claims, characterised in that the course of an edge (36) , which is formed by the lateral face (25) of the depression (24) forming an abrupt offset, is adapted to the curvature of the rotating yarn limb (17).
5. Open-end rotor spinning arrangement according to any of the preceding claims, characterised in that the distance a (29) between the edge (30, 36), formed by the lateral face (26) and the surface of the yarn withdrawal nozzle (10) , and the deepest point (31) in the base of the depression (24) is between 1 mm and 3 mm.
6. Open-end rotor spinning arrangement according to any of the preceding claims, characterised in that the yarn withdrawal nozzle (10) has only one single depression (24).
7. Open-end rotor spinning arrangement according to any of the preceding claims, characterised in that the lateral face (26) of the depression (24), rising in the rotational direction of the yarn, is convex.
8. Open-end rotor spinning arrangement according to any of the preceding claims, characterised in that the angular disposition of the depression (24), respectively fixed during the spinning operation, is changeable relative to the mouth (8) of the fibre guide conduit (7).
9. Open-end rotor spinning arrangement according to any of the preceding claims, characterised in that the angle α is between 15° and 25°.
10. Open-end rotor spinning arrangement according to any of the preceding claims, characterised in that the yarn withdrawal nozzle (10) is made of a ceramic material.

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