EP0684327B1 - Procedure and device for piecing on an open-end rotor spinning machine - Google Patents

Description

Method for piecing an open-end rotor spinning device, which has a spinning rotor, which is arranged in a housing covered by a removable cover, in which a negative pressure is brought into effect during the spinning process, the fiber feed being switched on in preparation for the piecing process, the separated fibers however prevented from being deposited in the fiber collecting groove of the spinning rotor and removed by negative pressure until, in coordination with the return of the thread, the fiber removal is ended and the fibers are fed into the fiber collecting groove for integration into the thread end returned to the spinning rotor and the withdrawal of the thread is started, and an apparatus for performing this method.

According to a known method of this type, the fibers to be discharged are fed in the housing of the opening device over the inlet opening of the fiber feed channel and to a suction line through which the fibers are discharged and thus prevented from being deposited on the fiber collecting surface (in the fiber groove) (WO 86/01235 A1). This has the advantage that there are no openings in the fiber transport path that are not provided here anyway - for example one Dirt separating opening - but this is bought with the disadvantage that a space-consuming and material-consuming fiber removal and control device is required.

DE 25 05 943 A1 describes a method for preparing the piecing process. After braking of the rotor, the feed roller, with which fibers of a sliver are fed to an opening roller, is rotated for a short time in order to feed a fiber strand end to the rotor. The fibers of this fiber strand end are removed together with dust and dirt by an air stream, after which the rotor is driven again, and the feed roller delivers a fiber strand end suitable for application into the rotor via the opening roller. In this known method, the fibers are always guided into the rotor and must be removed from the rotor again before the piecing process or the rotor must be cleaned. The rotor must stand still, causing an extension of the entire piecing process.

DT 19 32 009 discloses a spinning device with a drafting system and a method for piecing. In order not to have to change the feed channel in relation to the drafting system and thus to achieve a constant feed of the fibers, it is proposed to move the rotor and its bearing away from the feed point. This avoids overfeeding of the rotor if the thread breaks. As soon as the preparation for piecing has been completed, the rotor and its bearing are moved back to their original position. The disadvantage of this method is that, on the one hand, a great deal of effort has to be made for the movably designed storage. On the other hand, it is also disadvantageous that the entire rotor including the bearing has to be moved in order to switch the fiber feed, and thus repeat accuracy and speed the switching process, especially in modern, very fast spinning spinning machines, is not sufficient for high piecing quality.

DE 31 04 444 A1 describes a method with which fibers are prevented from entering the rotor. The fibers are guided past the circumference of the opening roller, past the fiber feed channel and conveyed into a discharge channel. A disadvantage of this device is a complex construction.

In DE 34 41 677 C3, the fiber stream on the opening roller is also prevented from entering the fiber feed channel. When piecing, a switchover takes place between the discharge point and the fiber feed channel in order to bring the fibers into connection with the inserted thread end. The switching time requires a certain lead in order to get the fiber stream at the right time in the To have a rotor. This control is relatively complex.

The present invention is therefore based on the object of providing a method and a device with the aid of which it is possible, while maintaining the advantages of the known method and the known device, to avoid the disadvantages indicated.

This object is achieved according to the invention by the features of claims 1 and 11. Advantageously, in preparation for the piecing process in the housing accommodating the spinning rotor, the vacuum for action and the rotor lid are brought out of its operating position into a fiber removal position in which it is lifted off the housing without the sealing effect between the rotor lid and housing being canceled and without Fiber transport path air is sucked in, then the fiber feed is switched on and the fiber stream generated thereby is redirected by the bundling of the air stream within the spinning rotor caused by the increase in the distance between the spinning rotor and the rotor lid, together with the air stream transporting the fibers, and by means of the underpressure effective in the housing the open rotor edge is removed from the inside of the rotor and the housing until the rotor cover is brought back into its operating position until fibers are fed to the fiber collecting surface. By bundling the air flow, the fibers are exposed to a more intense air flow than usual after switching on the fiber feed, which causes the fibers to be deflected from their previous trajectory while overcoming their inertia and fed to the suction via the open rotor edge. Thus, in this way, no fibers get onto the fiber collecting surface until the fiber removal is ended by returning the rotor cover to its operating position and the fibers are fed back to the fiber collecting groove for integration into the thread end are, wherein the thread end is made available in time coordination with the fiber feed to the fiber collection groove by return delivery to the spinning rotor for piecing.

According to an advantageous embodiment of the method according to the invention, the deflection of the fibers to be removed is favored in that the speed of the air conveying the fibers to the spinning rotor is reduced by introducing auxiliary air into the housing for the duration during which the rotor lid is in its fiber removal position .

According to an alternative method according to the invention, in order to prepare the piecing process, the negative pressure is first effective in the housing accommodating the spinning rotor and the rotor lid is brought from its operating position into a fiber removal position in which it is lifted so far from the housing that the negative pressure applied to the housing releases auxiliary air can suck in the space surrounding the housing, but there is no additional suction of air in the fiber transport path, so that the fiber feed is then switched on and the fiber stream thus generated is deflected by the resulting lower fiber acceleration after entering the interior of the spinning rotor together with the air stream transporting the fibers and is discharged from the inside of the rotor and the housing via the open rotor edge with the aid of the negative pressure effective in the housing, until fibers are fed to the fiber collecting surface of the rotor lid back into its operating position is brought. In this way, the fiber deflection and removal is promoted by the reduction in the speed of the air conveying the fibers to the spinning rotor.

In order to keep the fiber deflection of the fibers to be removed as low as possible, a further expedient embodiment of the method according to the invention provides that the in the housing for Effective negative pressure produces an air flow which is oriented essentially in the continuation of the direction of supply of the fibers. If the supply of auxiliary air is provided, it is advantageous for the above-mentioned reason if the auxiliary air is also oriented essentially in the fiber feed direction.

After attaching, the thread is pulled out of the spinning rotor again. Too sudden acceleration of the thread pull should be avoided in order to avoid thread breaks. In order to avoid a thick spot following the piecing or at least to make it inconspicuous, it is advantageous if the fibers fed to the spinning rotor for incorporation into the thread end in the take-off are adjusted in quantity to the acceleration. For this adaptation of the fiber flow supplied to the fiber collecting surface to the increase in speed of the newly spun and again drawn thread, the amount of fiber removed is reduced according to the invention in that the rotor lid is brought from its fiber removal position into its operating position in a controlled manner during the run-up of the thread take-off. In addition to or instead of the movement control of the rotor lid, it can also be provided according to the invention for this purpose that the intensity of the auxiliary air flowing into the housing is reduced in a controlled manner during the run-up of the thread take-off in order to adapt the fiber flow supplied to the fiber collecting surface to the speed increase of the newly spun and again drawn thread.

In order to favor the fiber deflection for the purpose of fiber removal, it is expediently provided that the fibers do not enter the spinning rotor obliquely in the direction of the fiber collecting groove, but rather that the fiber stream is deflected before being introduced into the spinning rotor in such a way that it is essentially parallel to that through the Fiber collecting groove oriented level is oriented.

According to the invention, to carry out the method, that a seal, which provides a seal between the two parts of the fiber feed channel in the operating position of the rotor lid, and a controllable opening device are assigned to the rotor lid, with the aid of which the rotor lid can be brought into a fiber removal position and into an operating position, the rotor lid in its The fiber removal position is only lifted so far from the housing that the sealing effect between the two parts of the fiber feed channel is still maintained and that the opening device is connected to the control device controlling the piecing process.

In order to avoid turbulence and sticking of fibers which could later become detached during the spinning process and thus lead to a disturbance of the spinning process, it is provided in an advantageous embodiment of the device according to the present invention that the part of the fiber feed channel arranged in the rotor lid has such an inlet cross section has that even when the rotor lid is in its fiber removal position, the part of the fiber feed channel arranged in the rotor lid does not protrude into the surface of the outlet cross section of the part of the fiber feed channel arranged in the opening device.

In order to exclude with certainty a fiber loss even in the fiber removal position of the rotor lid, it is advantageous if the rotor lid has a seal in addition to the seal between the two parts of the fiber feed channel, which cooperates with the housing, and the rotor lid through the opening device at the Movement into the fiber removal position can only be lifted from the housing to such an extent that the sealing effect between the rotor lid and the housing is maintained.

In order to enable a larger stroke movement of the rotor lid while maintaining the sealing effect between the rotor lid and the housing, can be provided according to the invention that the housing has a seal cooperating with the seal of the rotor lid. The seal of the rotor cover and / or the housing is preferably designed as a lip seal.

In order to favor the fiber deflection and removal, it is provided according to an advantageous embodiment of the subject matter of the invention that an auxiliary air opening, which opens into the housing and is controllably connected to the control device controlling the piecing process, is arranged in the rotor lid. A particularly favorable air flow with respect to fiber removal is achieved if the auxiliary air opening is arranged essentially on the side of the housing opposite the suction air opening with respect to the outlet opening of the part of the fiber feed channel arranged in the rotor lid.

According to a preferred embodiment of the device according to the invention, when the rotor lid carries a lip seal, it is provided that the auxiliary air opening is formed by the lip seal of the rotor lid and / or the housing accommodating the spinning rotor, which in the operating position of the rotor lid has an opening in a lip seal covers the receiving annular groove and in the fiber removal position of the rotor cover the opening in the annular groove is free. This results in a particularly simple way of controlling the auxiliary air as a function of the position of the rotor cover.

The method and the device according to the present invention enable the fibers to be removed as preparation for the piecing, so that the fibers suffered during the prior stoppage of the fiber feeding device are discharged and perfect fibers are available for piecing. This goal is achieved without any point in the fiber transport path between the fiber feeding device and spinning rotor must be engaged in the fiber transport path so that the device according to the invention has no negative effects on the normal spinning process. Since the suction device is used to remove the fibers, which is present anyway at each spinning station in order to generate the vacuum required for spinning, no separate discharge line with its control members is required. As said, the usual suction device with its standard control devices is sufficient, with the exception that the response torque is changed compared to previously known methods. Compared to the known opening movements of the rotor lid, according to the present invention, only the stroke path has to be changed and, if necessary, the seal has to be changed in order to bring about the desired sealing effect even in the fiber removal position of the rotor lid. Overall, changes are to be made predominantly in the control, drive and sealing elements of the rotor cover, which can also be carried out subsequently on rotor spinning devices already supplied to customers. The device is simpler in construction than known devices and even enables the amount of fibers to be incorporated into the thread end during the piecing draw-off to be controlled in a simple manner.

Fig. 1:

eine erfindungsgemäß ausgebildete Offenend-Spinnvorrichtung im Schnitt;

Fig. 2:

eine abgewandelte Offenend-Spinnvorrichtung im Schnitt;

Fig. 3 und Fig.4:

eine weitere Abwandlung des Erfindungsgegenstandes im Schnitt in der Schließ- bzw. Faserabführstellung des Rotordeckels; und

Fig. 5:

eine erfindungsgemäße Spinnvorrichtung mit einer Druckluftdüse.

Exemplary embodiments of the invention are explained in more detail below with the aid of drawings. Show it:

Fig. 1:

an open-end spinning device designed according to the invention in section;

Fig. 2:

a modified open-end spinning device in section;

3 and 4:

a further modification of the subject of the invention in section in the closed or fiber removal position of the rotor lid; and

Fig. 5:

a spinning device according to the invention with a compressed air nozzle.

The open-end spinning device shown in FIG. 1 is only shown schematically, the elements which are not necessary for understanding the invention being omitted.

A feed device 2 is provided for feeding a sliver 1 to be spun to an opening roller 3. From the opening roller 3, the fiber sliver 1, which is broken down into individual fibers, passes through a fiber feed channel 30 into the interior of a spinning rotor 4, where the fibers are deposited in the form of a fiber ring in a fiber collecting groove 40. The fiber ring is continuously spun into the end of a thread, not shown, which is drawn off through a thread draw-off tube 5 with the aid of draw-off rollers, not shown, and wound onto a bobbin, also not shown.

In the exemplary embodiment shown, the feed device 2 for the sliver 1 has a driven delivery roller 20, which is mounted on a continuous drive shaft 200 and can be individually controlled with a clutch, not shown. A feed trough 21 cooperates with the delivery roller 20, which is pivotably supported in a known manner by a housing 31 which accommodates the opening roller 3 mentioned.

The spinning rotor 4 is supported by means of a shaft 41 in the usual and therefore not shown manner through support disks or the like and extends through the bottom of a housing 60 which is connected to a vacuum source 610 via a suction air connector 61. The housing 60 is covered by a rotor cover 7, which receives at least part of the fiber feed channel 30 and carries the thread take-off tube 5.

The rotor lid 7 has a protruding into the interior of the spinning rotor 4 Lid extension 70, in which the outlet mouth of the fiber feed channel 30 and the inlet mouth of the thread take-off tube 5 are arranged. In addition, the cover extension 70 also receives a blow duct 81, which is fed by a compressed air line 8. In the compressed air line 8 there is a valve 82 which can be controlled by an extension 622 of a control lever 62.

The control lever 62 is pivotable about a horizontal axis 620 and has a switching cam 621 in the vicinity of this axis 620. A roller 630, which is arranged at one end of a two-armed lever 63, is supported on the control lever 62 in the region of the switching cam 621. The lever 63 is acted upon by a tension spring 631 so that the roller 630 always remains in contact with the control lever 62.

At the end facing away from the roller 630, the lever 63 is connected to a shift rod 632, which in turn is connected to a linkage 633. This linkage 633 is reproduced in a greatly simplified form in FIG. 1 and, in the embodiment shown, has a balance lever 634, one end of which is connected via a rod 635 to a brake 636 and the other end is connected via a rod 637 to a mechanism (not shown) for Lifting a drive belt 638 from the shaft 41 or to replace the drive belt 638 on the shaft 41.

The elements described are part of an open-end spinning device 6, which is covered by a cover 64. The control lever 62 is arranged in a slot of this cover 64 as long as it is in its basic position shown. The cover 64 carries the aforementioned valve 82. In addition, the cover 64 also carries the aforementioned rotor cover 7, so that when the cover 64 is folded down, the rotor cover 7 is also removed from the open side of the spinning rotor 4 and from the housing 60 becomes.

The cover 64 also carries a release lever 640, which holds the control lever 62 in the position shown by means of a tension spring 641 against the action of the tension spring 631, which acts on the control lever 62 and acts on the lever 63.

The cover 64 carries a further unlocking or release lever 642, which is acted upon by a tension spring 643 and is thereby held in the locking position shown, in which the release lever 642 engages behind a nose 310 of the housing 31. The unlocking or release lever 642 has the task of making it possible to lift the rotor lid 7 off the housing 60.

For the actuation of the release lever 640, an actuating lever or actuating arm 90 is provided, which is pivotably arranged on a piecing device 9, which can be moved along the open-end spinning machine, which has a multiplicity of similar work or spinning positions next to one another, each with an open-end spinning device 6. The actuating arm 90, which carries a roller 900 at its free end, is pivotably mounted on an axis 901 and is connected to a pivot drive 903 via a coupling member 902.

To return the control lever 62 to its basic position in alignment with the cover 64, a reset lever 904 with a roller 905 is provided on the piecing device 9 at its free end. The reset lever 904 is pivotable about an axis 906 and connected to a pivot drive 908 by means of a coupling member 907.

Similarly, an actuating lever or actuating arm 91 is provided for the actuation of the trigger lever 642, which moves around an axis 910 is pivotable and carries a roller 911 at its free end. A stop designed as a stop arm 912 is non-positively connected to the actuating arm 91 and is mounted on the same axis 910 for this purpose. This stop arm 912 carries a stop roller 913 at its free end. The actuating arm 91 is connected to a swivel drive 915 via a coupling member 914.

For returning the cover 64 to its closed position, a movable reset device 94 with a roller 943 at its free end is provided on the movable piecing device 9 and can be pivoted about an axis 942 and is connected via a coupling member 940 to a swivel drive 941.

The actuating arm 91 with its drive and the trigger lever 642 together form an opening device for the rotor lid 7, which - as will be explained in more detail - at least two working positions (positions I and II) are assigned. In addition, the rotor lid 7 can be brought together with the cover 64 in a known manner in a rest position, in which the cover 64 is folded down so far that the open-end spinning device 6 and its units are accessible.

The swivel drives 903, 908, 915 and 941 are connected via a control line 920, 921, 922 and 923 to a control device 92 of the piecing device 9, which in turn is connected via a control line 650 to a machine-side control device 65. The control device 65, which controls various functions not explained here, is also connected in terms of control, among other things, via a control line 651 to the previously mentioned, not shown coupling of the delivery roller 20.

After the structure of the open-end spinning device 6 and of the piecing device 9, the function of these devices in connection with piecing will now be described.

During the normal spinning process, the sliver 1 is fed in the usual way to the spinning rotor 4 after it has been dissolved into individual fibers, and is tied into the end of a thread which leaves the spinning rotor 4 through the thread take-off tube 5.

Should be spun at a spinning station that was previously out of operation for some reason, then the spinning vacuum - if this was switched off by interrupting the connection between suction air nozzle 61 and vacuum source 610 - is brought back into effect in a manner not shown, known per se and the spinning rotor 4 is driven again.

To initiate the piecing process, the control device 92 of the piecing device 9 actuates the swivel drive 903, which presses the roller 900 of the actuating arm 90 against the release lever 640 and thus releases the control lever 62, which now acts under the action of the tension spring 631 from the slot in the cover 64 mentioned is pushed out towards the piecing device 9. As a result, the control lever 62 with its extension 622 releases the valve 82, which in turn now releases the compressed air line 8, so that compressed air enters the blow duct 81.

Simultaneously with the pivoting of the control lever 62, the drive belt 638 is lifted from the shaft 41 of the spinning rotor 4 via the lever 63, the shift rod 632 and the linkage 633 and the brake 636 is brought into contact with the shaft 41. The spinning rotor 4 is thus braked to a standstill. During this braking of the spinning rotor 4, the compressed air already mentioned passes through the blowing duct 81 into the interior of the spinning rotor 4 and thus sweeps over the entire circumferential area of the spinning rotor 4. which is thus cleaned.

During rotor cleaning, the thread end to be spun is fed back from the bobbin, possibly a special piecing bobbin, to the spinning device 6 after it has received an optimal shape for the piecing in the usual way. Due to the negative pressure of the negative pressure source 610, the threading end is brought into a defined piecing position within the thread take-off tube 5.

To end the cleaning process, the swivel drive 908 is actuated by the control device 92 and the control lever 62 is brought back into alignment with the cover 64 by means of the roller 905, the roller 900 pushing the release lever 640 aside by simultaneously actuating the swivel drive 903. The roller 900 then releases the release lever 640, which now engages behind the upper end of the control lever 62. Now roll 905, which is no longer required, is withdrawn again. By returning the control lever 62 into its snap-in position in the cover 64, the spinning rotor 4 is released by the brake 636, which now starts up again due to the drive belt 638 which has come to rest against the shaft 41 again.

To prepare for piecing, after the control lever 62 engages in the cover 64, the rotor lid 7 is lifted from the housing 60 and thus from the open edge 42 of the spinning rotor 4 and brought into a removal position (position II). Here, the interior of the housing 60 is connected to the circulating air surrounding the housing 60 via a gap between the rotor lid 7 and the housing 60.

This opening of the rotor lid 7 is controlled by the movable piecing device 9. For this purpose, the swivel drive 915, which actuates the actuating arm, is actuated by the control device 92 91 presses with its roller 911 against the trigger lever 642. As a result, the release lever 643 is unhooked from the nose 310 of the housing 31, whereupon the cover 64 falls due to the force of gravity in the direction of the piecing device 9 until the cover 64 comes to rest against the stop roller 913, which now assumes the position 913a (see dashed illustration ). This tilting of the cover 64 is brought about in that, with respect to the axis 620, the entire mass of the cover 64 and the parts connected to it are arranged on the side of the axis 620 facing the piecing device 9.

From the control device 92, the clutch (not shown) of the delivery roller 20 is now actuated via the machine-side control device 65, so that the sliver feed to the opening roller 3 is resumed. The combed fibers from the front end of the sliver 1 enter the fiber feed channel 30. Since the rotor cover 7 occupies position II, in which, due to the negative pressure generated by the vacuum source 610, auxiliary air from the housing 60 through the gap between the rotor cover 7 and the housing 60 surrounding space is sucked in, the vacuum effect exerted by the vacuum source 610 in the fiber feed channel 30 is reduced, so that the acceleration of the air transporting the fibers within the fiber feed channel 30 is reduced in comparison to normal spinning operation, in which the rotor lid 7 has its operating position (position I ) occupies in which no air can penetrate into the housing 60 between the housing 60 and the rotor lid 7.

As a result of the reduced air speed and due to the resulting lower fiber acceleration and thus lower fiber speed, the fibers have - compared to the spinning process - a lower inertia. They thus better follow the transport air flow sucked over the open rotor edge (edge 42 of the spinning rotor 4) into the suction air nozzle 61 and become dissipated together with this. This removal of the fibers is further promoted by the fact that because of the lifting of the rotor cover 7 from the housing 60 and transfer into its position II, the deflection required for removing the air and the fibers is anyway less than during the normal spinning process, during which the rotor cover 7 is in position I.

Due to the standstill of the sliver 1 during the time preceding the piecing with still and / or while the opening roller 3 is running, the front end of the sliver 1 is exposed to the combing action of the opening roller 3, whereby this front end of the sliver is thinned, combed, shortened and combed. This band end thus contains a length range which is not or only partially suitable for piecing, the impairment of the band end depending on the downtime of the fiber feeding device 2 with the opening roller 3 running.

By removing the fibers immediately before the actual piecing process, the part of the fiber sliver 1 which is undesirable for piecing is removed. As soon as this has been done, the end of the thread is returned to the spinning rotor 4 in its fiber collecting groove 40 in mutual timing and by returning the rotor cover 7 to its operating position (position I) - with the aid of the reset lever 94 controlled by the swivel drive 941 and its roller 943 - the fibers are delivered into the fiber collecting groove 40 of the spinning rotor 4, where the fibers and the thread end unite. The thread is then withdrawn from the fiber collecting groove 40 of the spinning rotor 4 with the continuous incorporation of fibers and wound onto a spool (not shown). The piecing process is now complete.

All working elements of the piecing device 9 now return to their basic position at the latest, whereupon the piecing device 9 can resume its journey along the rotor spinning machine.

Since the fibers which are unsuitable for piecing and are therefore undesirable are removed via the open rotor edge, no intervention in the normal fiber transport path between the fiber feed device 2 and the exit of the fiber feed channel 30 is necessary. The consequence of this is that the fiber transport into the spinning rotor 4 can in no way be disturbed in any way during the spinning process. In addition, there are practically no temporal shifts between the change in the fiber transport path (first for discharging the fibers into the suction air nozzle 61 and then into the spinning rotor 4 for collecting the fibers in the fiber collecting groove 40), since the deflection point is located in the rotor area. A temporal coordination of the effect of the fiber flow in the spinning rotor 4 on the return delivery and pulling off the thread again during piecing can thus be achieved in a very exact manner.

As shown in Fig. 1, the inlet mouth 300 of the part of the fiber feed channel 30 located in the rotor lid 7 is so large that the part of the fiber feed channel 30 arranged in the rotor lid 7 is neither in the position I nor in the position II of the rotor lid 7 in the area of the Exit cross section of the part of the fiber feed channel 30 arranged in the opening device protrudes so that the fibers emerging from the part of the fiber feed channel 30 arranged in the housing 31 can reach the part of the fiber feed channel 30 located in the rotor lid 7 unhindered by protruding edges. For this reason, the part of the fiber feed channel 30 that has the inlet mouth 300 is funnel-shaped and dimensioned accordingly. In addition, a seal 32 is provided in the housing 31 (and / or in the rotor cover 7), both in the position I and in the position II of the rotor cover 7 for a secure seal between the housing 31 and the rotor lid 7 and prevents air from being sucked into the fiber transport path.

In order to prevent fibers from escaping between the rotor lid 7 and the housing 60 accommodating the spinning rotor 4, no special measures are generally to be taken, since the air flow entering through the gap formed between the rotor lid 7 and the housing 60 returns the fibers into the housing 60 - And the suction air nozzle 61 supplies. In order to increase the certainty that no fibers can emerge here, it can also be provided in an alternative embodiment of the device described that the housing 60 and / or the rotor lid 7 (each) carries or carry a seal 600 which is designed in this way that it seals the interior of the housing not only in position I of the rotor cover 7, but also in its position II with respect to the atmosphere surrounding the housing 60.

If the sealing effect between the rotor lid 7 and the housing 60 is not canceled, then due to the increase in the distance between the spinning rotor 4 and the rotor lid 7, the air flow is concentrated within the spinning rotor 4 and over its open edge 42, since the air emerging from the fiber feed channel 30 then selects the shortest route to the suction air nozzle 61, while the air leaving the spinning rotor 4 flows in the position I of the rotor lid 7 - to enable the required air throughput - distributed over the circumference over the open edge 42 of the spinning rotor 4.

An embodiment in which the sealing effect between the rotor lid 7 and the housing 60 is also maintained in the position II of the rotor lid 7 is shown in FIGS. 3 and 4, with FIG. 3 the rotor lid 7 in its position I, ie in its operation - And closed position, and Fig. 4 shows in its position II, ie in its fiber removal position.

Both the housing 60 receiving the spinning rotor 4 and the rotor cover 7 each have an undercut annular groove 601 or 71, in each of which a lip seal 602 or 710 protruding from the annular groove 601 or 71 is arranged.

As shown in FIG. 3, the lips 603 and 711 lie against the base body of the lip seals 602 and 710 as long as the rotor lid 7 is in its position I. However, if the rotor lid 7 is brought into its position II, the lips 603 and 711 spread apart from the base bodies of the two lip seals 602 and 710 and push the base bodies of the lip seals 602 and 710 out of the ring grooves 601 and 71, insofar as this is the position of the rotor lid 7. Fig. 4 clearly shows that the position II of the rotor cover 7 and the lip seals 602 and 710 are matched to one another such that the sealing effect between the lip seals 602 and 710 and thus also between the rotor cover 7 and the housing 60 in position II of the rotor cover 7 is still guaranteed.

Compared to the device discussed with the aid of FIG. 1, no air thus penetrates into the housing 60 at this point. Rather, the negative pressure generated with the aid of the negative pressure source 610 can have a full effect on the inside of the rotor. Although the fibers are accelerated in this way, they are safely fed to the suction air nozzle 610 as a result of the more intensive bundled suction air flow. This is - as with the help of the device shown in Fig. 1 - further favored in that the exit of the fiber feed channel 30 has been moved somewhat out of the spinning rotor 4 in the position II of the rotor lid 7, so that the fibers do not have a large deflection on their Find out about the open edge 42 of the spinning rotor 4.

The fiber guide can be used for both the spinning process and the fiber removal immediately before the actual piecing is further favored in that the fibers are not fed obliquely to the plane through the fiber collecting groove 40 into the spinning rotor 4 (see FIG. 1), but instead pass from the fiber feeding channel 30 into a slot 33 which is oriented parallel to the plane mentioned. During spinning, the fibers reach the same height line on the inner wall of the spinning rotor 4, which leads to a particularly uniform fiber deposition in the fiber collecting groove 40, so that a particularly good quality thread is spun. However, if the rotor cover 7 is in its fiber discharge position (position II), the fiber removal is particularly favored in that the fibers from their fiber feed direction, which they have received in the fiber feed channel 30, into a plane parallel to the plane through the fiber collecting groove 40 and thus also be oriented to the plane through the open edge 42 of the spinning rotor 4, this slot 33 in the position II of the rotor lid 7 already being lifted out of the interior of the spinning rotor 4 to a certain extent, so that a large part of the slot 33 leaving fibers to fly over the open edge 42 of the spinning rotor 4 does not need to be deflected at all in order to get into the space surrounding the spinning rotor 4 within the housing 60.

In order to keep the deflection of the fibers emerging from the fiber feed channel 30 and to be supplied to the suction air nozzle 61 small, it is further provided that the suction air nozzle 61 is arranged essentially in the extension of the fiber feed channel 30. As a result, an air flow is generated by the vacuum source 610 in the spinning rotor 4, which air flow is oriented essentially in the continuation of the feed direction of the fibers leaving the fiber feed channel 30, which promotes fiber removal, since the deflection of the transport air is as small as possible.

It has been shown that fiber removal is advantageous to support in principle in their discharge direction by an air flow supplied from the rear extension of the fiber feed direction. In principle and irrespective of whether the rotor cover 7 is sealed in its position II with respect to the housing 60 or not, a controllable air supply connection (not shown) can open into the housing 60 in relation to the suction air nozzle 61 in order to introduce auxiliary air into the housing 60 during fiber removal . This auxiliary air flow favors the supply of the fibers to the suction air connection 61, since it is oriented essentially in the direction of the fiber supply.

This supplied air flow is expediently guided in such a way that it reaches the spinning rotor 4 from the side opposite the suction air nozzle 61 and leaves the spinning rotor 4 in the region of the exit of the fiber feed channel 30 and thereby takes along the fiber stream leaving the fiber feed channel 30 and over the open edge 42 of the spinning rotor 4 leads away. It is provided, as shown in FIG. 1, that - with respect to the drawing plane - the fiber feed channel 30 is oriented essentially in the direction of the suction air nozzle 61. In such a case, it is provided that such an air supply duct 72 is arranged in the rotor cover 7 and (in contrast to the design shown in FIGS. 3 and 4) has an outlet opening which as directly as possible into the spinning rotor 4, i.e. within the circular area enclosed by the open edge 42 of the spinning rotor 4, opens out.

Another alternative solution is shown in dashed lines in FIGS. 3 and 4. According to this solution, an air supply duct 720 - with respect to the fiber transport direction - opens behind the outlet mouth of the fiber feed duct 30 into the slot 33, so that the fibers are exposed to the air flow entering through the slot 33 from the slot 33 and fed to the suction air nozzle 61.

Although various inventive features have been shown in combination in FIGS. 3 and 4, it goes without saying that other combinations are also possible within the scope of the present invention and individual features can be replaced by equivalents. For example, it is not necessary to provide an externally controlled valve to control the supply air flow in the supply air opening or in the air supply duct 72 or 720. 3 and 4 show, it is also entirely possible to inevitably couple the air supply through the air supply duct 72 or 720 to the respective position I or II of the rotor cover 7. According to the embodiment of the spinning device shown in FIGS. 3 and 4, for example the lip 711 of the lip seal 710 of the rotor cover 7 is designed as a valve. For this purpose, the lip 711 has a window 712 which, according to FIG. 3, lies in position I of the rotor cover 7 against the bottom 713 of the annular groove 71 and is covered with it, i.e. closed is.

3 and 4 show that the air supply duct 72 and 720 is arranged radially with respect to the spinning rotor 4. It is arranged so that it crosses the annular groove 71.

As long as the window 712 abuts the bottom 713 of the annular groove 71, the air supply duct 72 or 720 is interrupted in the region of the annular groove 71 by the lip seal 710 (position I of the rotor cover 7). However, if the rotor lid 7 is in its fiber removal position (position II), the lip 711 which spreads apart from the base body of the lip seal 710 releases the window 712, which now allows air to flow through. If the rotor lid 7 returns to its operating position (position I), the air flow is prevented again.

It goes without saying that instead of a lip seal 602 or 710, other seals can also be used. Depending on the training, this seal can then also, if necessary control a supply air opening. However, if desired at all, a supply air opening can also be provided, which can be controlled depending on the position I or II of the rotor cover 7, but works independently of the seal.

A modification of the device, by means of which fiber deposition on the fiber collecting groove 40 before the actual piecing is prevented, is explained below with the aid of FIG. 2. Here, too, the sealing effect between the housing 60 and the rotor cover 7 is retained when the latter is in its position II.

As FIG. 2 shows, the housing 60 can be covered by a cover 67, which slidably receives a rotor cover 670. With the position 67 of the cover relative to it unchanged, this rotor lid 670 can assume a first position I, the operating position during the normal spinning process, and a second position II, the fiber removal position during the piecing preparation. A sleeve 671 is provided as a guide for the rotor cover 670 in the cover 67, in which the thread take-off tube 5 is guided, which in turn is rigidly connected to the rotor cover 670 and has a stop ring 50 at its end located outside the cover 67, with which a fork 93 can work together.

The fork 93 is mounted on the piecing device 9 (FIG. 1) and can be moved both horizontally and vertically in such a way that it reaches the stop position shown, in which it cooperates with the stop ring 50, and also moves it out of this stop position can be.

A compression spring 672 is supported on the one hand on the inner wall of the cover 67 and on the other hand on the radial surface of the rotor cover 670 facing the end face of the cover 67. The rotor lid 670 has a cover extension 70, in which a partial section 301 of the fiber feed channel 30 is arranged.

In the operating position, the rotor lid 670 assumes the position I shown in broken lines, in which the subsection 301 forms the continuation of the fiber feed channel 30. If, at the end of the fiber supply to the fiber collecting groove 40, the fiber stream is to be fed to the suction air nozzle 61 over the open edge 42 of the spinning rotor 4, the rotor lid 670 is brought into position II with the aid of the fork 93 brought into engagement with the stop ring 50. The section 301 of the fiber feed channel 30 has dimensions such that even in this position of the rotor cover 670, the fibers safely reach the section 301. Here again it is provided that as far as possible no protruding edges protrude into the fiber transport path - although such projections may be necessary. can be tolerated to influence the fiber orientation (also in a device according to FIG. 1).

After completion of the stopping process, the fork 93 releases the stop ring 50 again, so that the rotor lid 670 returns to its position I by the action of the compression spring 672.

According to yet another alternative embodiment of the method (not shown), regardless of whether the gap between the open rotor edge and the rotor lid 7 or 670 is increased or not, it is provided that the air flow supplied to the suction air nozzle 610 is intensified. For this purpose it can be provided that a changeover valve (not shown) is provided in the suction air line leading to the vacuum source 610, which in one position connects the housing 60 to a first suction line in which the vacuum required for spinning is provided, and in the other position with a second suction line (not shown), which increases Provides negative pressure. If the housing 60 is connected to this second suction line with the increased negative pressure in preparation for piecing to remove the fibers, a more intensive air flow also arises in the fiber feed channel 30 or in the subsection 301 thereof, so that the out of the fiber feed channel 30 or its subsection 301 emerging fibers better follow the intensification of this suction air flow and thus be prevented from accumulating in the fiber collecting groove 40 of the spinning rotor 4.

The degree of opening of the rotor lid 7 (Fig. 1, 3 and 4) or 670 (Fig. 2) significantly influences the removal of fibers in the suction air nozzle 61. For this reason, it is possible to determine the amount of the suction air nozzle 61 and thus also the To control the amount of fibers fed to the fiber collecting groove 40 by not only suddenly moving the rotor cover 7 or 670 back from its fiber removal position (position II) to its operating position (position I), but rather by gradually moving this movement in a controlled manner. There is thus a division of the fiber stream leaving the fiber feed channel 30. This is of particular advantage for piecing. If, after the thread has been attached to the fiber ring which is forming again in the spinning rotor 4, the thread is pulled off, it can only be drawn off gradually to avoid excessive tension in the thread and / or because of the inertia of the masses to be accelerated, for example the bobbin will. However, if the fiber stream is immediately completely fed back to the fiber collecting groove 40 when the rotor cover 7 or 670 is returned, a larger amount of fiber temporarily enters the spinning rotor than can be bound and drawn off by the thread in the acceleration phase. The consequence of this is a thick point in the piecing or in the thread area adjoining it. However, if the rotor lid 7 or 670 is controlled, ie only slowly, possibly even non-linearly, in adaptation to the increase in speed of the newly spun-on thread, which is now in the take-off position, returned from its fiber feed position (position II) to its operating position (position I), so that the fiber mass entering the fiber groove is essentially as large as the fiber mass drawn off by the thread at the same time, Such thick spots are avoided.

In order to control the portion of the fiber stream which is deposited in the spinning rotor 4 in adaptation to the thread take-off acceleration, it can alternatively or additionally be provided that the intensity of the auxiliary air stream flowing into the housing 60 is reduced in a controlled manner. In the case of the embodiment shown in FIGS. 3 and 4, this takes place simultaneously with and by the closing movement of the rotor cover 670. Otherwise, a correspondingly controllable throttle valve can be provided in the line supplying the auxiliary air (not shown).

The control of the piecing and thus also the fiber removal as preparation for piecing using a piecing device 9 has been described above, but it goes without saying that in the absence of a piecing device 9 that can be moved along the rotor spinning machine, the units required for piecing and controlling the fiber flow and elements can also be provided stationary at the (or each) spinning station.

Figure 5 shows a further embodiment of the invention. A rotor lid 770 has a fiber feed channel 772. A compressed air nozzle 771 is arranged shortly before the mouth of the fiber feed channel 772. The compressed air nozzle 771 has a feed line which opens at the cover 67. From there it can be supplied with compressed air by means of a compressed air source, not shown. The compressed air source can be delivered to the supply line. The compressed air nozzle 771 is inclined towards the mouth of the fiber feed channel 772. It causes a fiber and air flow, which emerges from the mouth of the fiber feed channel 772, is supplied with additional compressed air and is deflected in such a way that both the fiber stream and the air stream are deflected out of the rotor interior. The fiber flow and air flow are led out of the housing via the suction air connection 61. The control for the compressed air supply can be arranged either at each spinning station or on the spinning machine or on a movable maintenance device, not shown. In the latter case, it is delivered to the spinning station at which a piecing process is to be carried out. The control device has an operative connection to a higher-level control device, which controls the use and the end of the compressed air supply and the return of the thread end.

Claims (19)

1. A method of joining [in] an open-end rotor spinning device, comprising a spinning rotor (4) which is mounted rotatably in a stationary mounting and is arranged in a housing (60) which is covered by a removable cover (7) and in which an underpressure is applied during the spinning procedure, wherein, in order to prepare for the joining procedure, the fibre feed (2) is switched on, the fibres are separated by means of a separating roller (3), but the separated fibres are prevented from being deposited in the fibre-collecting channel (40) of the spinning rotor and are removed by [the] underpressure, until the fibre removal is terminated in accordance with the thread return and the fibres for piecing are supplied to the thread end of the fibre-collecting channel (40) returned to the spinning rotor (4) and the draw-off of the thread is taken up, characterized in that, in order to prepare for the joining procedure, the underpressure is applied in the housing (60) receiving the spinning rotor (4) and the rotor (4) is rotated, the fibre feed (2) is switched on and the fibre flow produced thereby together with the air flow conveying the fibres is supplied in the direction of the spinning rotor (4) through a fibre-feed duct (30, 300) arranged at least in part in the cover (7), the fibre flow and the air flow are first jointly removed from the interior of the rotor and the housing (60) over the open edge of the rotor, as the fibre flow and the air flow are deflected from their usual course during the spinning procedure by lifting the cover (7) and/or an additional air supply, and, in order to piece the fibres into the thread end returned to the spinning rotor, the fibre flow and the air flow are separated by closing the cover and/or by shutting off the additional air supply (81), so that the fibres of the fibre-collecting channel (40) and the air flow are removed in turn from the interior of the rotor and the housing (60).
2. A method according to Claim 1, characterized in that the rotor cover (7) is moved from its operating position (I) into a fibre-removal position (II), in which it is lifted off the housing (60) without the sealing effect between the rotor cover (7) and the housing (60) being discontinued and without air being drawn into the fibre-feed duct (30, 300), the fibre feed (2) is switched on and the fibre flow produced thereby is deflected inside the spinning rotor (4) together with the air flow conveying the fibres by the convergence of the air flow resulting from the increase in the distance between the spinning rotor (4) and the rotor cover (7) and is removed over the open edge of the rotor from the interior of the rotor and the housing (60) with the aid of the underpressure prevailing in the housing, until the rotor cover (7) is moved back again into its operating position (I) in order to supply fibres to the fibre-collecting channel (40).
3. A method according to Claim 2, characterized in that auxiliary air is introduced into the housing (60) during the time in which the rotor cover (7) is in its fibre-removal position.
4. A method according to Claim 1, characterized in that the rotor cover (7) is moved from its operating position (I) into a fibre-removal position (II), in which it is lifted so far off the housing (60) that the underpressure prevailing at the housing (60) can draw in auxiliary air from the space surrounding the housing, but an additional drawing-in of air in the fibre-feed duct (30, 300) does not take place, the fibre feed (2) is switched on and the fibre flow produced thereby is deflected together with the air flow conveying the fibres by the resulting lower fibre acceleration after entering the interior of the spinning rotor and is removed over the open edge of the rotor from the interior of the rotor and the housing (60) with the aid of the underpressure prevailing in the housing, until the rotor cover (7) is moved back again into its operating position (I) in order to supply fibres to the fibre-collecting channel (40).
5. A method according to Claim 4, characterized in that the auxiliary air is orientated substantially in the fibre-supply direction.
6. A method according to one or more of Claims 1 to 5, characterized in that the underpressure which can be applied in the housing (60) produces an air flow which is orientated substantially in a continuation of the supply direction of the fibres.
7. A method according to one or more of Claims 1 to 6, characterized in that, in order to adapt the fibre flow supplied to the fibre-collecting surface to the increase in speed of the thread which has been newly joined and drawn off again, the removed quantity of fibres is reduced by the rotor cover (7) being moved from its fibre-removal position (II) into its operating position (I) in a controlled manner during the run-up of the thread draw-off.
8. A method according to one or more of Claims 4 to 7, characterized in that, in order to adapt the fibre flow supplied to the fibre-collecting surface to the increase in speed of the thread which has been newly joined and drawn off again, the intensity of the auxiliary air flowing into the housing (60) is reduced in a controlled manner during the run-up of the thread draw-off.
9. A method according to one or more of Claims 1 to 8, characterized in that the fibre flow is deflected in such a way before insertion into the spinning rotor (4) that it is orientated substantially parallel to the plane extending through the fibre-collecting channel (40).
10. A method according to Claim 1, characterized in that a compressed-air nozzle (771) arranged at the opening of the fibre-feed duct (30, 300) is acted upon with compressed air, as a result of which the fibre flow and the air flow are jointly removed from the interior of the rotor and the housing, and the compressed air is shut off in order to separate the fibre flow from the air flow.
11. A device for joining [in] a rotor open-end spinning device, with a spinning rotor (4) which is arranged in a housing (60) covered by a removable cover (7) and connected to an underpressure source (610) by way of an air-intake opening, with a fibre-feed device (2) by which a sliver (1) is supplied to a separating device (3) for separating, with a fibre-feed duct (30, 300) extending from the separating device (3) into the spinning rotor (4) and arranged in part in the separating device (3) and in the rotor cover (7) in each case, with a thread-return and a thread-draw-off device as well as with a control device (92) controlling the joining procedure and with a seal (32) associated with the rotor cover (7) and providing for sealing between the two parts of the fibre-feed duct (30, 300) in an operating position (I) of the rotor cover, for performing the method according to one or more of Claims 1 to 10, characterized in that a controllable opening device (91, 910 to 915; 93), with the aid of which the rotor cover (7, 670) can be moved into a fibre-removal position (II) and into the operating position (I), is associated with the rotor cover (7; 670), wherein the rotor cover (7; 670) is raised in its fibre-removal position (II) so far off the housing (60) that the sealing action between the two parts of the fibre-feed duct (30, 300) is maintained in the operating position (I) and in the fibre-removal position (II), the opening device (91, 910 to 915; 93) is connected to the control device (92) controlling the joining procedure, and the rotor cover (7) has a further seal (600; 710) cooperating with the housing (60), and the rotor cover (7) can be raised by the opening device (91, 910 to 915) during the movement into the fibre-removal position (II) only so far off the housing (60) that the sealing action between the rotor cover (7) and the housing (60) is maintained in the fibre-removal position (II).
12. A device for joining [in] a rotor open-end spinning device, with a spinning rotor (4) which is arranged in a housing (60) covered by a removable cover (7) and connected to an underpressure source (610) by way of an air-intake opening, with a fibre-feed device (2) by which a sliver (1) is supplied to a separating device (3) for separating, with a fibre-feed duct (30, 300) extending from the separating device (3) into the spinning rotor and arranged in part in the separating device (3) and in the rotor cover (7) in each case, with a thread-return and a thread-draw-off device as well as with a control device (92) controlling the joining procedure and with a seal (32) associated with the rotor cover (7; 760) and providing for sealing between the two parts of the fibre-feed duct (30, 300) in the operating position (I) of the rotor cover (7; 760), for performing the method according to one or more of Claims 1 to 10, characterized in that a controllable opening device (91, 910 to 915; 93), with the aid of which the rotor cover (7, 670) can be moved into a fibre-removal position (II) and into an operating position (I), is associated with the rotor cover (7; 670), wherein the rotor cover (7; 670) is raised in its fibre-removal position (II) so far off the housing (60) that the sealing action between the two parts of the fibre-feed duct (30, 300) is maintained in the operating position (I) and in the fibre-removal position (II), and the opening device (91, 910 to 915; 93) is connected to the control device (92) controlling the joining procedure, and an auxiliary-air opening (81; 72; 720; 712), which is connected in a controllable manner to the control device (92) controlling the joining procedure and which opens into the housing (60), is arranged in the rotor cover (7, 670).
13. A device according to Claim 11 or 12, characterized in that the part of the fibre-feed duct (30) arranged in the rotor cover (7, 670) has an entry cross-section which in the operating position (I) and in the fibre-removal position (II) does not project into the face of the outlet cross-section of the part of the fibre-feed duct (30) arranged in the separating device (31).
14. A device according to Claim 13, characterized in that the housing (60) has a seal (602) cooperating with the seal (710) of the rotor cover (7).
15. A device according to Claim 13 or 14, characterized in that the seal (710 or 602 respectively) of the rotor cover (7) and/or of the housing (60) is constructed in the form of a lip seal.
16. A device according to one of Claims 12 to 15, characterized in that the auxiliary-air opening (72; 720; 712) is arranged essentially on the side of the housing (60) opposite the air-intake opening (61) with respect to the outlet opening of the part of the fibre-feed duct (30) arranged in the rotor cover (7).
17. A device according to one or more of Claims 15 and 16, characterized in that the auxiliary-air opening (712) is formed by the lip seal (710; 602) of the rotor cover (7) and/or of the housing (60) receiving the spinning rotor (4), the lip seal (710; 602) covering an opening (72; 720) in an annular groove (712; 601) receiving the lip seal (710; 602) in the operating position of the rotor cover (7) and freeing the opening (72; 720) in the annular groove (712; 601) in the fibre-removal position (II) of the rotor cover.
18. A device for joining [in] a rotor open-end spinning device, with a spinning rotor (4) which is arranged in a housing (60) covered by a removable cover (7) and connected to an underpressure source (610) by way of an air-intake opening, with a fibre-feed device (2) by which a sliver (1) is supplied to a separating device (3) for separating, with a fibre-feed duct (30, 300) extending from the separating device (3) into the spinning rotor (4) and arranged in part in the separating device (3) and in the rotor cover (7) in each case, with a thread-return and a thread-draw-off device as well as with a control device (92) controlling the joining procedure, for performing the method according to Claim 10, characterized in that in the rotor cover (770) a compressed-air nozzle (771) is arranged at an inclination in the region of the opening of the fibre-feed duct (772) from the interior of the rotor to the edge of the rotor, so that compressed air flowing out of the compressed-air nozzle (771) conveys the fibre flow and the air flow out of the interior of the rotor.
19. A device according to Claim 18, characterized in that a control device is arranged on the spinning device in order to act upon the compressed-air nozzle (771) with pressure.

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