WO2023131697A1

WO2023131697A1 - Method and apparatus for introducing a false twist, and spinning machine

Info

Publication number: WO2023131697A1
Application number: PCT/EP2023/050286
Authority: WO
Inventors: Gernot Schaeffler; Peter Blankenhorn; Nora Stopp; Felix Heltsche; Ida POTTHARST
Original assignee: Maschinenfabrik Rieter Ag
Priority date: 2022-01-10
Filing date: 2023-01-09
Publication date: 2023-07-13
Also published as: DE102022100422A1

Abstract

The invention relates to a method, an apparatus and a spinning machine for introducing a false twist into a thread (7), wherein a thread running plane (20) is formed by the largely direct course, in plan view, of the thread (7) through a drafting unit (3) to a spinning device (17), and the thread (7) leaves the drafting unit (3) at an output pinch point (6) formed by an upper roller (4) and/or a lower roller (5). The thread (7) runs between the output pinch point (6) and the spinning device (17) via a roll (8) rotating about an axis of rotation (15) that is inclined with respect to the thread running plane (20), and in the process rotates simultaneously about its longitudinal axis, wherein a false twist is introduced into the thread (7) in the process. The thread (7) runs, between the roll (8) and the spinning device (17), through a thread guide (9) or between the roll (8) and the output pinch point (6). The roll (8) is held in more than two positions (25, 26), wherein, in the first position (25), it is arranged in the thread run of the thread (7) and is driven by the thread (7) and, in the second position (26), it is arranged outside the thread run and is not driven.

Description

Method and device for false twist introduction and spinning machine

The present invention relates to a method for introducing false twists into a thread, with a thread running plane being formed by the thread running largely directly in plan view through a drafting system to a spinning device and the thread leaving the drafting system at an exit nip point formed by an upper roller and/or a lower roller . The thread runs between the output clamping point and the spinning device over a roller rotating about an axis of rotation that is inclined to the thread running plane, the thread simultaneously rotating about its longitudinal axis and thereby introducing a false twist into the thread. The thread runs through a thread guide between the output nip point of the pair of take-off rollers and the spinning device. The invention also relates to a device for introducing false twists into a thread on a spinning machine, with a roller and a holder for the roller, the roller being arranged on the holder so that it can rotate without a motor drive, and a corresponding spinning machine.

US Pat. No. 2,718,111 A discloses a spinning device with a roller as a false twist element. The roller is driven by a worm. The housing in which the roller is mounted can be rotated around the worm. The roller always remains driven and in the direction of the grain. The drive of the roll is energy-intensive and must be matched to the speed of the thread.

DE 6941966 U discloses a device for false twisting of monofilaments or filament yarns made of linear high polymers by wrapping around a rotatable roller arranged at an angle to the running direction of the monofilaments or filament yarns. The false twist element consists of a single, freely rotatable roller with a concave thread running surface, with the thread running surface is a surface of revolution preferably symmetrical to the perpendicular bisector of the axis of rotation of the roller. The run-up angle of the thread on the false twist unit is variable. However, the thread always remains in contact with the reel. The disadvantage here is that the roller of the false twist unit cannot be moved out of the yarn path. This is a hindrance, particularly when changing bobbins and when piecing, but also when the spinning device is to be used without a false twist unit.

Furthermore, it is problematic that at low delivery speeds, in particular shortly before doffing, the roller applies very high tension to the thread, which can lead to thread breakage.

The object of the present invention is therefore to eliminate the disadvantages of the prior art.

The object is achieved by a method, a device and a spinning machine with the features of the independent patent claims.

In a method according to the invention for introducing false twists into a thread, a thread running plane is formed by the thread running largely directly in plan view through a drafting system to a spinning device. The thread leaves the drafting system at an exit nip formed by an upper roller and/or a lower roller. The thread runs between the output clamping point and the spinning device over a roller rotating about an axis of rotation that is inclined to the plane of the thread travel. The thread runs through a thread guide between the exit clamping point and the spinning device.

According to the invention, the roller is held in more than two positions, in the first position it is arranged in the yarn path of the yarn and is driven by the yarn and introduces the false twist into the yarn. This first position denotes the normal spinning position. When the roller is placed in the second position, it is out of the threadline and is not driven. This position is preferred when no false twist is to be created in the spinner or when the doffer needs space to change bobbins.

If the roller is in at least one or more further positions, which is/are arranged between the first and the second position, in which it has no contact with the thread or a lesser false twist than in the first position in the Thread brings in, no or only a lower force is applied to the thread. In particular at a lower spinning speed, as is usually the case when changing a cop, ie doffing, this causes the thread to run more stably. The risk of yarn breakage can thus be reduced.

The roller does not have its own drive, but is driven exclusively by the running thread. On the one hand, this saves energy and, on the other hand, no control is required to adapt the speed of the roller to the speed of the thread. The introduction of the false twist takes place exclusively by the fact that the thread is deflected from the roller from its original plane of thread travel and the axis of the roller is aligned at an angle to the longitudinal axis of the thread. This creates lateral forces on the thread, which rotate the thread about its longitudinal axis and thus introduce a false twist into the thread.

By being able to hold the reel in more than two positions, the reel can be driven by the thread in the first position. In the second position, the roller is no longer in the yarn path and is accordingly no longer driven. In this second position of the role, it is also possible that a bobbin change or a Piecing process can be carried out without the role would hinder this. It is also possible for the spinning device to be operated with or without a false twist unit. The spinning position can therefore be used in a variety of ways without the need for complex conversion work.

In the at least one further position, the roller is either held in such a way that it still contacts the thread and is thus driven. However, the deflection of the thread from its straight course is lower here than during spinning at operating or production speed. It is also possible that this or another position is provided next to the straight line of the thread and the thread thus has no contact with the roller. The role is thus no longer driven. Due to the lower deflection of the thread, the tension applied to the thread is also lower than when deflecting with the roller in the first position. The risk of yarn breakage is thus reduced. This position is particularly important in a doffing process in which the thread is spun at a lower delivery speed than during full production.

The following procedure is advantageous for a doffing process: Beginning with the spinning process, especially during the last stroke of the ring rail, the yarn guide with the roller attached to it swivels slightly up from the first position to a third position, in which the yarn is deflected slightly less than during the current one spinning process. However, the thread is still in contact with the roller and drives it, albeit with less friction than in the first position. The ring rail then begins to wind the thread on the spool. Now the thread guide with the roller pivots back to a fourth position so far that the roller is no longer in engagement with the thread. As a result, the roller is no longer driven. In the next step, the ring rail moves to its lowest position. The thread guide can with swing the roller all the way up to the second position. This creates space for an autodoffer, which automatically carries out a bobbin change. Alternatively, especially when changing bobbins manually, the thread guide with the roller can swivel into the first position and is ready for another spinning onto the new tube.

The main advantage of the third or fourth position is that when the spindle is rotating very slowly or is stationary, the thread can no longer be pulled over the roller, or at most only very slightly.

It is particularly advantageous if a plurality of rollers, which are assigned to adjacent spinning devices, can be moved simultaneously and/or individually between the first, the second and the at least one further position. Particularly in the case of a simultaneous movement of the rollers from the first to the second and/or into the at least one further position and vice versa, in the case of a bobbin change at several spinning positions, the corresponding preparation can be carried out by removing the rollers from the bobbin changing area or by reducing the force on the thread be carried out quickly and reliably. Alternatively or additionally, a single roll can be moved individually from the first to the second or further position and vice versa. This creates the possibility of individual adjustment of each individual spinning position with regard to false twist initiation or bobbin change.

Furthermore, it is advantageous if the roller is moved together with the thread guide and/or individually, independently of the thread guide, between the first and/or the second and/or the at least one further position. If the roller is moved between the positions together with the thread guide, the thread guide can also be removed very quickly from the area of the bobbin change when changing the bobbin. This will be sufficient in most cases. However, if the roller for the false wire introduction is to be used as an option, see above it is advantageous if the roller can be moved between the positions independently of the thread guide, that is to say individually in relation to the thread guide.

It is particularly advantageous if the thread is moved through the roller into the at least one further position in a preparatory phase of a doffing process and/or at a reduced speed of the spinning device compared to the operating speed, in particular at a speed of less than 10,000 revolutions/minute becomes. In this particularly critical phase, this creates very good spinning stability.

Preferably, the thread is moved laterally out of the plane of the thread run by the roller and the thread wraps around the upper roller or the lower roller after the exit nip point in such a way that it introduces another false twist into the thread. The thread and the roller as well as the thread and the upper roller or the lower roller thus cross one another, so that the thread nestles against the lateral surface of the roller and the lateral surface of the upper roller or the lower roller during the deflection. False twist is introduced into the thread both on the roller and on the upper and lower rollers. The spinning stability can be significantly increased by the two points at which the false twist is introduced into the yarn, without the quality of the yarn produced suffering as a result of the introduction of too high a permanent twist.

If, in an advantageous embodiment of the invention, the roller is arranged in the second position or in the at least one further position without contact with the thread during the doffing process, the thread can be held or produced by the false twisting device without additional tension, thereby reducing the risk of a yarn breakage is reduced. The roller can also be moved into an area in which it does not impede the device for doffing, particularly in the case of automatic doffing.

It can also be advantageous if the thread is raised or lowered compared to the course of the thread without a roller in addition to the lateral deflection, so that the operation of the spinning station can be simplified either by an operator or by a robot. In addition, a collision of a robot with the thread can be avoided, in particular when the thread is pressed into the spinning machine by means of the roller, ie is lowered.

Depending on the operating speed of the spinning device, the roller is preferably moved into at least one further position, in particular into a plurality of further positions. Thus, when the operating speed is low, the roller can assume a position which causes the thread to be deflected to a lesser extent than in another position which is intended for a higher speed. There is thus a variable immersion depth in the yarn path or a variable yarn wrapping around the roller depending on the spindle speed.

In a further advantageous embodiment, the axis of rotation of the rotating roller is arranged at an angle α or β between 30° and 60° to the thread path when viewed in the plane of the thread run and/or when viewed on the plane of the thread run. Provision is preferably made for the angle α or β to be changed as a function of the operating speed of the spinning device. There is thus an adjustment of the incline of the roller depending on the spindle speed. The roll is twisted in relation to the grain line.

A device according to the invention for introducing false twist into a thread on a spinning machine has a roller and a holder for the roller on. The roller is rotatably arranged on the holder without a motor drive. According to the invention, the holder is attached to a bearing in order to be able to assume more than two positions, the first position being such that when the device is used as intended, the roller is arranged in the course of the thread and the thread presses against the roller with a first force whereby the roller is driven by the thread and in the second position the roller is located outside the thread path and is not driven. According to the invention, in at least one further position, which is arranged between the first and the second position, the roller has no contact with the thread and is therefore not driven. The further position can also be such that the thread presses against the roller with a second force which is less than the first force, as a result of which the roller (8) is driven. The thread tension can be reduced as a result, which reduces the risk of thread breakage.

The device can be arranged at each spinning position of the spinning machine. In addition, the device is designed to be retrofitted to an existing spinning machine. Since the roller is driven by the running thread, a separate motor with a corresponding power supply and control is not required. It is precisely for this reason that the subsequent installation of the device on an existing spinning machine is particularly easy. Due to the different positions of the roll, the spinning machine can be used either with or without a false twist device. The particular advantage of the device attached to the spinning machine is that the roll can be arranged in one position during operation, which is optimal for the false twist, but on the other hand through the second or further position for a bobbin change and a piecing process at one can be placed in a non-interfering place. The further position can also ensure a stable doffing process due to less false twisting. It is particularly advantageous if the holder has a guide element for the thread. In particular, when the roller is swiveled back into the thread path of the thread from outside the thread path, it must be ensured that the thread actually runs over the roller and does not slip off to the side. The guide element, which is designed, for example, in the form of a hump with a guide surface, ensures that the thread is always guided to the roller.

It is also advantageous if the bearing is a rotary bearing or a sliding bearing. With a swivel bearing, the roller can be pivoted very easily around a pivot point, so that it can move from the first to the second position. Ideally, the weight distribution of the holder with the roller is such that it is stable in the first and second positions. In this case no additional device, such as a spring, is required to ensure the first or second position. With a sliding bearing, the roller with its holder can be moved between the two positions by a linear or arcuate displacement. Here, too, it should be ensured that the respective position can be maintained independently, preferably without additional aids, and must first be actively actuated in order to move from this one position to the other position. For the stable position in the at least one further position, a catch or a stop can be provided, which can be overcome or removed when the position is to be left.

Furthermore, it is advantageous if the position of the holder is determined by a latching device of the bearing, in particular with a cam or a magnet, and/or by a stop. The stop ensures that the position of the holder with its role is at a defined point. A cam or magnet fixes the desired position sufficiently so that the roller cannot unintentionally leave this position. Only active actuation of the holder by pulling it out of the latching device in the Moving to the other position will cause the holder, and therefore the roller, to change position. With a corresponding weight distribution of the roller and the holder, it may also be sufficient that there is only one stop against which the holder rests in order to define the first or second position.

There are also advantages if the bearing is movable or immovable and has a receptacle for attachment to a preferably pivotably mounted yarn guide or longitudinal component of the spinning device. The recording is advantageously designed so that the device can be retrofitted to the spinning machine. In this case, for example, an already existing longitudinal component of the spinning device is used in order to attach the device to it. It is particularly advantageous if the receptacle is designed in such a way that the device can be arranged on the yarn guide that is already present at the spinning station. This also makes it very easy to subsequently attach the false twisting device to an existing spinning machine, for example with a clip connection. In addition, the mobility of the thread guide can be used to pivot the false twisting device at the same time as the thread guide. The false twisting device to be attached to the spinning device can thus be designed very simply and inexpensively.

A spinning machine according to the invention has a large number of spinning stations, each of which includes a drafting system, a spinning device and a device for introducing false twist into a thread. A thread running plane is formed by the largely direct course of the thread through the drafting system to the spinning device in a top view, and the drafting system has an exit nip with an upper roller and/or a lower roller, at which the thread leaves the drafting system. Is between the output nip point of the pair of take-off rollers and the spinning device, as a device for false twist introduction into a thread, a role with a axis of rotation aligned obliquely to the plane of the thread running, with the running thread rotating about its longitudinal axis as it passes the roller and thereby receiving a false twist. A thread guide is arranged between the output nip point of the pair of take-off rollers and the spinning device. The roller is rotatable on a holder without a motor drive.

According to the invention, the holder is fixed in a bearing to be able to occupy more than two positions, the first position being such that the roller is arranged in the threadline of the thread and driven by the thread and in the second position arranged outside the threadline and not is driven. The two positions allow the roller to be brought into engagement with the thread, creating a false twist in the thread. Alternatively, the roller is disengaged from the thread or is in the position where the thread does not run. It can either be provided that a thread is produced which has no false twist or the roll is only in this position for the time during the bobbin change and the piecing process in order not to impede the bobbin change and the piecing process. If the roller is in at least one further position, which is arranged between the first and the second position, in which it has no contact with the thread or deflects the thread less than in the first position from a rectilinear course, then, in particular with a Doffing the thread are less or not loaded at all, reducing the risk of thread breakage is reduced.

It is advantageous if the holder or the bearing is arranged on the thread guide or on a component of the spinning station, in particular on a longitudinal component of the spinning machine. By arranging the bearing or the device on the thread guide, the roller can be moved together with the thread guide from the thread engagement of one position to the other position in which there is no thread engagement. Is the warehouse or the holder is fastened to a component of the spinning station, in particular to a longitudinal component of the spinning machine, a simple arrangement of the false twisting device on the spinning machine is possible.

It is also advantageous if the thread guide or the component of the spinning station, in particular the longitudinal component on which the holder or the bearing is arranged, is designed to be rotatable. Due to this very special advantage, the false twisting device or the roller can be adjusted from one position to the other by rotating the component, which preferably runs along several spinning positions. If several false-twisting devices of several adjacent spinning positions are arranged on one component, a simultaneous adjustment of these several false-twisting devices or rollers is possible.

If the holder for the roller and/or the thread guide with the holder for the roller arranged thereon is assigned a drive for moving the roller into at least one of the three positions, the required position can be approached in a targeted manner.

Preferably, the axis of rotation of the rotating roller is arranged at an angle of between 30° and 60° to the thread path when viewed in the thread path plane and/or when viewed onto the thread path plane and engages in the straight thread path in such a way that the thread turns around at the same time rotates its longitudinal axis. This exerts a force on both the thread and the roller. This force causes the thread to rotate about its longitudinal axis and creates the false twist in the thread, which contributes to the spinning stability of the thread.

The roller is preferably arranged on the spinning machine in such a way that the thread is raised or lowered in the thread running plane in addition to the lateral deflection compared to the course of the thread without a roller. lowers is. The thread thus runs above or below the normal course of the thread, as it would be without the false twisting device according to the invention. If the thread run is raised, the operation of the spinning position is simplified, especially when attaching a thread. If, on the other hand, the yarn path is lowered, i.e. closer to the machine than with the normal yarn path, a robot patrolling along the spinning machine can drive past the spinning position without the risk of colliding with the yarn.

It is also advantageous if the roller is arranged in such a way that the thread is deflected laterally out of the thread running plane by the roller and the thread contacts the upper roller or the lower roller after the exit nip point in such a way that this introduces a second false twist into the thread. The thread and the roller as well as the thread and the upper roller or the lower roller thus cross one another, so that the thread nestles against the lateral surface of the roller and the lateral surface of the upper roller or the lower roller during the deflection. False twist is introduced into the thread both on the roller and on the upper and lower rollers. The second false twist may have the twist in the same direction or in the opposite direction of the induced rotation of the roller 8. The spinning stability can be significantly increased by the two points at which the false twist is introduced into the yarn, without the quality of the yarn produced suffering as a result of the introduction of too high a permanent twist.

With the inclined roller, false twist is introduced in the direction of the spinning triangle in the area between the drafting system outlet and yarn guide. The higher twist improves spinning stability. In this way, either the spindle speed or, with a constant spindle speed and a smaller alpha, the delivery speed can be increased without sacrificing the spinning stability and tear resistance of the yarn compared to classic spinning. On the other hand, compared to classic spinning, the delivery speed is the same the spindle speed is reduced and the required spinning power per kilogram of spun yarn is lowered.

The roll is in the grain line. According to the invention, the roller is temporarily pivoted out of the yarn path. Thus, when the sleeve is raised - and especially when doffing - the thread guide and roller are to be brought outside the area of the sleeve body.

The reel is rotated by the thread. The forces that have to be absorbed by the thread when piecing to accelerate the roll, especially in the area of the weak piecing, can make piecing more difficult, especially in the case of delicate piecings. In these cases it is better if the roll is first brought out of the yarn path and only pivoted into the yarn path after piecing.

With long spinning geometries it may be that the roller is not in the doffer area. It therefore does not have to be moved back when doffing. In this case, the roller is placed on a stationary traverse. During piecing, the roll is moved into its piecing position outside of the yarn path and brought back into its spinning position after piecing. Locking positions can be provided for piecing and spinning positions. These positions can be realized, for example, either by means of resilient cams, but also with magnets.

The reel falls best into its spinning position due to its weight. Alternatively, it can also be brought into the other position with a spring.

Since in most machine types all the rollers have to be swung out of the doffer area during doffing, it is better to fix the rollers on a traverse that can be rotated centrally. With this Traverse, all rolls on one side of the machine can be moved out of the doffer area and back into the spinning position after the doffing process.

Both thread guide and roller are preferably seated on a rod running through the machine. Yarn guide carrier and roll holder can be positioned axially together by a clamping ring. The clamping ring can be provided with common stops for the spinning and doffing positions. The roller can preferably be brought into the piecing position independently of the thread guide. It is advantageous if the roll holder is seated on the carrier of the thread guide in the spinning position.

So that the roll holder can be retrofitted into an existing spinning machine, it can also be clipped onto a rod. It is also possible to use a half-shell for fixing, which is clipped or screwed into the holder.

In a further advantageous embodiment, the holder of the roller is placed directly on the thread guide and screwed or clipped onto the carrier of the thread guide.

The advantage of this solution is the controlled thread guidance through the thread guide arranged very close to the roller.

With the inclined roller, the spinning speed can be increased or the yarn twist reduced. In addition, an optimization of the yarn path geometry is possible with the roller. The associated advantages, such as improved yarn quality in terms of hairiness and strength, softer yarn twist and improved feel in the end product, improved spinning stability, higher production or possible power savings per kilogram of yarn spun, make the inclined roller an extremely interesting spinning component. The invention is designed in accordance with the foregoing description, with the features mentioned being able to be present individually or in any combination.

Further advantages of the invention are described in the following exemplary embodiments. It shows:

Figure 1 is a side view of a spinning position of a ring spinning machine,

FIG. 2 shows a front view of a spinning position of a ring spinning machine,

FIG. 3 shows a side view of a spinning position with the thread deflected upwards according to FIG. 2,

FIG. 4 is a front view with the thread deflected to the right,

FIG. 5 a roll with a deflected thread,

FIG. 6 shows a side view of a false twisting device according to the invention,

FIG. 7 shows a front view of a false twisting device according to the invention,

FIG. 8 shows a side view of the false twisting device from FIG. 7,

FIG. 9 shows a front view of another false twisting device according to the invention,

FIG. 10 shows a side view of the false twisting device from FIG. 9, FIG. 11 is a front view of another false twisting device according to the invention,

FIG. 12 shows a side view of the false twisting device from FIG. 11,

FIG. 13 is a front view of another false twist device according to the invention in the first position in the yarn path,

FIG. 14 is a front view of the false twisting device from FIG. 13 in the second position outside the threadline.

In the following description of alternative exemplary embodiments, the same reference symbols are used for features that are identical and/or at least comparable in their design and/or mode of operation compared to the other exemplary embodiments. If these are not explained again in detail, their design and/or mode of action corresponds to the design and mode of action of the features already described above. Said roller can have different lateral surfaces, which are, among other things, in particular a cylinder, a cone or a paraboloid, even if only one cylinder should be mentioned or shown in the individual case.

FIG. 1 shows a side view of a spinning position 1 of a ring spinning machine. A fiber structure 2 runs through a drafting system 3 and is drafted in the process. He leaves the drafting system 3 at a pair of rollers, which consists of an upper roller 4 and a lower roller 5. Upper roller 4 and lower roller 5 form an output nip 6 in which the fiber structure 2 is clamped. In so-called compression spinning, instead of the upper roller 4 or the lower roller 5, a suction pipe can also be present, which is wrapped around by a small sieve belt and generates a negative pressure. The top roller 4 or the bottom roller 5 presses on the screen apron and clamps the fiber structure 2 also at a corresponding output clamping point 6. From the output clamping point 6, a thread 7 provided with a twist is formed from the fiber strand 2. The thread 7 then reaches a false twisting device 22, in which it wraps around a roller 8 set at an angle to the thread path, then passes through a thread guide 9 to a spinning device 17. The spinning device 17 comprises a rotor 10 and a sleeve 11, onto which the thread 7 is wound becomes. The thread 7 forms a thread balloon 12 between the thread guide 9 and the runner 10. The sleeve 11 rotates at the speed of the spindle carrying it about a spindle axis 14, while the runner 10 is dragged along a spinning ring 13 by the winding thread 7 at a slightly lower speed. The spinning ring 13 is moved in the vertical direction relative to the sleeve 11 and thus winds up the thread 7 produced on the sleeve 11 to form a coil with thread layers.

When the sleeve 11 is wound with sufficient thread 7, the sleeve is removed from the spinning device 17 and replaced with an empty sleeve 11. This process is called doffing. The spinning ring 13 is located in the lower area of the sleeve 11 and the thread 7 is attached to the sleeve 11 and separated. When removing the wound tube 11 and inserting the empty tube 11, care must be taken that the thread guide 9 does not impede the necessary movements of the tube 11. It is therefore often provided that the thread guide 9 can be moved to a position outside the spindle axis 14 in which it allows the sleeve 11 to be changed very easily, also automatically.

Between the output clamping point 6 and the thread guide 9, the thread 7 runs in the false twisting device 22 over the roller 8, which is rotatably mounted about an axis of rotation 15. The roller 8 deflects the thread 7 from its normal thread path 16 indicated by dashed lines and lifts it out of this thread path 16 . In this side view, the roller 8 is pivoted at an angle β between 30° and 60° to the normal thread path 16 . The thread 7 thus does not contact the roller 8 perpendicularly to the roller Axis of rotation 15 of the roller 8, but at an angle, so that tangential forces act on the thread 7. The tangential forces cause the thread 7 to rotate, which creates a false twist between the exit nip point 6 and the thread guide 9 .

FIG. 2 shows a front view of the spinning position 1 of a ring spinning machine. In this representation, the roll 8 can be seen as it is arranged at the spinning station 1. The roller 8 is located in the area of a thread running plane 20. The thread running plane 20 is defined by the path of the fiber structure 2 through the drafting system 3 and further along this line through the spindle axis 14. As can be seen from this illustration, the thread 7 remains on its Away from the drafting system 3 to the thread guide 9 largely in this thread running plane 20. Smaller deviations from this due to the thread 7 clinging to the roller 8 or by the rotation of the thread guide 9 are not taken into account. The thread running plane 20 thus essentially corresponds to the drawing plane of FIG.

From this representation of FIG. 2, it is clearly evident that the roller 8 is arranged inclined at an angle α to the plane 20 of the thread travel. The thread 7 runs obliquely over the roller 8, as a result of which tangential forces arise on the thread 7, which introduce a false twist into the thread 7.

The angles α and β can be adjusted depending on the operating speed of the spinning device or the spindle speed. A variable setting of the appropriate angle, possibly even automatic setting with a motorized setting device, is also possible.

FIG. 3 shows a side view of a spinning position 1 with the thread deflected upwards according to FIG. The roller 8 and the thread guide 9 are arranged above the sleeve 11. From this representation it can be seen that both the yarn guide 9 and the roller 8 at a Change the sleeve 11 are a hindrance, since the sleeve 11 must be pulled up from its spindle. Accordingly, it is advantageous that the thread guide 9 and the roller 8 are removed when a wound bobbin has to be exchanged for an empty tube.

FIG. 4 shows a front view of the spinning station 1 with the roller 8, which deflects the thread 7 to the right. It would also be possible for the roller 8 to be arranged in such a way that it deflects the thread to the left. The inclination of the roller 8 can also be reversed. The same applies mutatis mutandis to the illustrations in FIGS. 1, 2 and 3. Here, too, the inclination of the roller 8 can be carried out in the direction other than that illustrated. Likewise, the thread can be pressed down instead of up, as shown in FIG. While in the illustration in FIG. 1 the thread 7 contacts the top roller 4 after the nip 6 and thereby receives another false twist, the thread 7 after the nip 6 is free according to the illustration in FIG. After the nip point 6, it no longer has any contact with the upper roller 4 or the lower roller 5 and therefore does not receive any false wire from these two rollers.

The forces on the thread 7 and the roller 8 are shown in FIG. The roller 8 rotates because of the thread 7 pulled over it. The thread 7 is deflected by the roller 8 . The thread tension F is divided into a component FA in the axial direction and a component FR in the radial direction. The roller 8 is driven by the radial force component FR. Due to the axial component FA, the thread 7 moves along the outer surface of the roller 8. The axial component FA can in turn be broken down into a component FL aligned in the direction of the thread run and a component FT-WIRK perpendicular to the yarn axis. The component FT-WIRK perpendicular to the yarn path corresponds to the force that acts on the outer diameter of the yarn 7 and with which the torsional moment for the false twist is introduced. The false twist insertion depends on the diameter of the roller 8, the coefficient of friction of the lateral surface of the roller 8, the deflection of the thread 7 or its angle of wrap around the roller 8, the inclination of the roller 8 to the undeflected thread 7, the number of rollers 8 used and the ease of movement of the roller 8.

The optimum angle of inclination of the roller 8 for inserting the false twist is in the range of 30°-60° to the line of the thread run 16 of the undeflected thread 7 (see FIGS. 1, 2).

The surface of the roller 8 can be ceramic, a steel body with a rough hard coating, or a material such as rubber or a synthetic material such as elastomers, e.g. B. nitrile butadiene rubber (NBR, cover of top rollers).

The roller 8 should be easy to move. Suitable bearings for the roller 8 are small, oil-lubricated roller bearings, plain bearings with shafts smaller than 4 mm or aerostatic air bearings. However, rollers 8 with a defined braking torque can also be used to optimize the insertion of the false twist.

The false twisting device with the roller 8 is preferably attached to the structure of the spinning machine 1 by means of a holder 21 .

In order to introduce false twist into the yarn, in the prior art the thread 7 is often pulled over a web which is inclined relative to the thread path. Frictional forces occur due to the coefficient of friction and the inclination of the web as well as due to the wrapping of the thread 7 around the web. The thread friction to be overcome acts only to a small extent as a torsional moment for false twist initiation on the thread 7. The maximum possible initiation of false twist twists is limited by the maximum possible thread tension. The thread tension increase as a result of the physical relationships described by the Euler-Eytelwein equation can be reduced if the sloping web is replaced by the easily rotatable roller 8. The thread 7 is pulled over the roller 8. The roller 8 rotates as a result. So that the thread 7 slides and/or rolls in the axial direction on the rotating roller 8. Since the friction of smooth-running bearings is much lower than the friction that occurs when the thread 7 is pulled over a fixed web, the rotating oblique roller 8 with reduced yarn tension forces, a significantly higher torsional moment can be exerted on the yarn 7.

A side view of a false twisting device 22 is shown in FIG. The roller 8.1 is arranged on the holder 21 in such a way that its axis of rotation 15 is at an angle to the run of the thread 7. As a result, the thread 7 is deflected from its normal, straight path of the thread. This rectilinear course of the thread can be recognized by the thread 7 shown in dashed lines. The holder 21 is attached to a longitudinal component 23 of the spinning machine, which runs in the longitudinal direction of the machine at least along one spinning position 1 , preferably along several spinning positions 1 .

A pivot bearing 24 is arranged on the holder 21 . The pivot bearing 24 enables the roller 8.1 to be positioned in a first position 25 and in a second position 26 shown in dashed lines, shown as the roller 8.2. While the roller 8.1 deflects the thread 7 in the first position 25, it is in the second position 26 (roller 8.2) pivoted far out of the straight path of the thread 7 shown in dashed lines, so that there is no longer any contact with the thread 7. In the first position 25, the spinning position, the roller 8.1 can thus introduce a false twist into the thread 7, while in the second position 26 the thread 7 is spun without a false twist can be. This second position 26 of the roller 8.2 is advantageous, in particular when changing the tube 11 or when piecing the thread 7 after a thread break or on an empty tube 11.

According to Figure 6, the pivot bearing 24 also enables the stable positioning of the roller 8 in the other positions 43 and 44. The 3rd position 43 is designed such that the roller 8.3 the thread 7 according to the double-dotted line only slightly deflects. The force on the thread 7 is lower here than in the position 25 of the roller 8.1. This position 25 can be taken when a bobbin change is imminent. False twist can still be introduced into the thread 7, but the risk of thread breakage is reduced in this case. In the further, fourth position 44, the roller 8.4 is in the dot-dash position. In this position, the thread 7 is no longer in contact with the roller 8.4 and thus runs in a straight line. In this position 44, the path for changing the sleeve 11 is not free, but the roller 8.4 can quickly be brought back into position 8.1 or 8.3, in which a false twist is introduced into the thread 7. This position is useful, for example, when the thread 7 was broken and needs to be reattached, or when the bobbin change is largely complete.

In order to be able to assume the positions 25, 26, 43 and 44 in a stable manner, a locking device is arranged in the rotary bearing 24. The locking device consists of an elastically mounted cam 27 which can be turned within an outer ring 28 of the pivot bearing 24 . In this exemplary embodiment, the cam 27 is, for example, an elastically mounted ball. By turning the roller 8, the cam 27 engages either in a first groove 29 or in a second groove 30 of the outer ring 28. By overcoming the elasticity of the cam 27, the roller 8 can be moved into the first position 25 or into the second position 26 and locked there. The same applies to positions 43 and 44. Grooves 45 and 46 are also provided for this purpose, in which the cam 27 can engage. It is also possible for the position to be taken with a motorized adjustment device. This motorized or, of course, also a manual setting device can also be controlled or set in such a way that, depending on the operating speed of the spinning device or the spindle speed, it specifies a position of the roller 8 which, at a higher spindle speed, results in a greater looping and deflection of the thread 7 than at a lower spindle speed.

The axis of rotation 15 of the roller 8.1 in the first position 25 is shown here perpendicular and thus parallel to the machine longitudinal direction or the longitudinal component 23 of the spinning machine. However, it can also be advantageous for the axis of rotation 15 to be positioned at a slight incline to the machine longitudinal direction in this position. Depending on the thread 7 to be produced, an angle of +/- 15°, preferably +/- 10°, can ensure a better, more stable thread 7 and a lower number of thread breaks.

FIG. 7 shows a sectional front view of an embodiment of the false twisting device 22 . In this exemplary embodiment, the longitudinal component 23 is a rod which runs along the spinning machine and which can be made rotatable about its axis. A clamping ring 31 is provided on the longitudinal component 23 for the axial fixing of the false twisting device 22 and is fastened to the longitudinal component 23 in a rotationally fixed manner by means of a screw 32 . The holder 21 is rotatably mounted on the longitudinal member 23 . It encompasses the clamping ring 31 on both sides, as a result of which the roller 8 with its holder 21 is fastened axially to the longitudinal component 23 .

FIG. 8 shows a side view of FIG. 7 in section. From this it can be seen that the clamping ring 31 has four grooves 29, 30, 45 and 46. With the grooves 29, 30, 45 and 46 corresponds the ball 27, which is elastically prestressed (not shown). The holder 21 can relative to the longitudinal member 23, for example manually, rotated, whereby the ball 27 engages in the grooves 29, 30, 45 and 46 and the further rotation of the holder 21 is arrested. The roller 8 with its holder 21 can thus be locked in four positions, which correspond to the positions 25 and 26 and 43 and 44. By rotating the rod of the longitudinal component 23, it is also possible for the holder 21 to be rotated from its first position 25 into other positions. The adjustment of the roller 8 from one position to another position can thus take place on the one hand by rotating the longitudinal component 23 . On the other hand, the roller 8 can also be adjusted manually to one of the positions 25, 26, 45 or 46.

Similar to FIGS. 7 and 8, FIGS. 9 and 10 also show a front view and a side view of a false twisting device 22 in section. As can be seen from the front view of FIG. 9, the holder 21 of the roller 8 has a receptacle 18 with which it is clipped onto a carrier 37 fixed axially to the clamping ring 31 . In contrast to FIGS. 7 and 8, the clamping ring 31 is not arranged on the rod of the longitudinal component 23, but fixedly on the spinning station 1. The carrier 37 carries the thread guide 9, which is arranged in the vicinity of the roller 8. About the support 37 of the thread guide 9, also like the roller 8, in several positions 25, 26, 43 and 44 are pivoted. For this purpose, the clamping ring 31 again has grooves 29, 30, 45 and 46. The roller 8, which is fixed to the support 37 of the yarn guide 9, is in its first position. To reach the other positions, the roller 8 is pivoted backwards together with the longitudinal component 23 and the thread guide 9 . This is shown with dashed lines.

In order to be able to assume the various positions, the carrier 37 is fastened to the longitudinal component 23 in a rotationally fixed manner with the screw 32 . The longitudinal component 23, which is designed here as a rod, is arranged on a drive 47 and can be rotated with it into the various positions. The carrier 37 is also rotated by this rotation. For a safe Positioning of the carrier 37 and the roller 8 arranged on it, the grooves 29, 30, 45 and 46 are again provided, in which the ball 27, which is attached to the holder 37, can engage. Alternatively, particularly if the drive 47 is to be controlled precisely, it is also possible to dispense with this latching device.

This exemplary embodiment is particularly advantageous since it enables a corresponding false twisting device 22 with the roller 8 to be retrofitted to an existing spinning machine with a swiveling thread guide 9 in a very simple manner. Hardly any conversion measures are therefore required, which is why this is a particularly advantageous and cost-effective variant of the present invention.

Another embodiment of the present invention is shown in FIGS. 11 and 12 in front and side views. The longitudinal component 23 is surrounded by the support 37 for the thread guide 9 and the holder 21 of the roller 8. Carrier 37 and holder 21 can be rotated about longitudinal member 23 . They are in turn fixed by the clamping ring 31 in their axial direction. They can be rotated from the first position 25 to the second position 26 both together and independently of one another. In the first position 25, the pin 36 of the carrier 37 of the thread guide 9 strikes the stop 34 of the clamping ring 31. In this position, the holder 21 contacts an elevation 38 of the carrier 37. If necessary, the roller 8 with its holder 21 can be rotated about the longitudinal component 23 into the second position 26, with an edge of the holder 21 striking the stop 33 of the clamping ring 31 , as shown in Figure 12 with a broken line. The carrier 37 with the thread guide 9 can continue to remain in the first position 25. Alternatively, in addition to the holder 21, the carrier 37 with the thread guide 9 can be rotated about the longitudinal component 23 and also remain in the second position 26. The twisting can take place until the elevation 38 of the carrier 37 hits the holder 21 . Of course it is also possible here for the longitudinal component 23 to be twisted, so that both the roller 8 and the thread guide 9 switch between the two positions 25 and 26 together. In addition, it is also possible to assume the positions 43 and 44 (FIG. 6) in that the longitudinal component 23, here a rod, is rotated with the aid of the drive 47.

FIG. 13 shows a front view of a further false twisting device 22 according to the invention in the first position 25 in the yarn path. The thread 7 runs over the surface of the roller 8 and through the thread guide 9. The roller 8 is attached to the holder 21. The holder 21 of the roller 8 is in turn attached to the carrier 37 for the thread guide 9 with 39 claws. With the claws 39, it can be quickly clipped onto the carrier 37 if a corresponding false-twisting device 22 is to be retrofitted. A guide element 40 for the thread 7 is arranged on the holder 21 . In this exemplary embodiment, the guide element 40 is designed in the manner of a hump in the region of the bearing of the roller 8 on the holder 21 . In the first position 25 of the false twisting device 22 there is no contact between the thread 7 and the guide element 40 .

FIG. 14 shows a front view of the false twisting device 22 from FIG. 13 in the second position 26 outside the yarn path. This second position 26, folded away from the operating position, is assumed, for example, when a doffing process is being carried out at the spinning station. In this position, the roller 8 has no contact with the thread 7. The thread 7 only runs through the thread guide 9. The thread run is along the guide element 40, with the thread 7 being close to the guide element 40 or even lying against it. It is essential that when the roller 8 moves back into the first position 25, the thread 7 does not slip off the roller 8--on the left in this illustration--but comes to lie securely on the circumference of the roller 8, as shown in FIG. The guide element 40 therefore forms a stop when the roller 8 moves back into the first position 25, which ensures that the thread 7 is pushed onto the circumference of the roller 8.

The guide element 40 can also be more or less pronounced than shown here. As a rule, it has the form of a shield or fender. What is important is that on the one hand there is no disruptive contact with the thread 7 in the position shown in FIG. 13 and on the other hand the thread 7 cannot slip off the roller 8 in the position shown in FIG. The present invention is not limited to the illustrated and described embodiments. Modifications within the scope of the patent claims are just as possible as a combination of the features, even if they are shown and described in different exemplary embodiments. For example, it is possible for only three positions to be provided instead of the four positions shown in the exemplary embodiments. It is also possible that more than the four positions shown are preset.

Reference character list

1 spinning position

2 fiber bandage

3 drafting system

4 top roller

5 bottom roller

6 output terminal point

7 threads

8 roll

9 thread guides

10 runners

11 sleeve

12 thread balloon

13 spinning ring

14 spindle axis

15 axis of rotation

16 grain line

17 spinning device

18 recording

20 grain level

21 holders

22 false twist device

23 longitudinal member

24 pivot bearings

25 first position

26 second position

27 cam, ball

28 outer ring

29 first groove

30 second groove 31 clamping ring

32 screw

33 stop

34 stop

35 pen

36 pin

37 carriers

38 Elevation

39 claw

40 guiding element

41

42

43 third position

44 fourth position

45 slots

46 slots

47 drive a angle ß angle

F thread tension

FA axial force component

FR radial force component

FL component aligned in the direction of the grain

FT-WIRK vertical component

Claims

P atentclaims Process for introducing false twists into a thread (7), a thread running plane (20) being formed by the thread (7) running largely directly in plan view through a drafting system (3) to a spinning device (17) and the thread ( 7) leaves the drafting system (3) at an exit nip (6) formed by an upper roller (4) and/or a lower roller (5), the thread (7) between the exit nip (6) and the spinning device (17) via a rotating roller (8) running at an angle to the thread running plane (20), the thread (7) simultaneously rotates about its longitudinal axis and thereby introduces a false twist into the thread (7) and the thread (7 ) between the output clamping point (6) and the spinning device (17) runs through a yarn guide (9), characterized in that the roller (8) is held in more than two positions (25, 26, 43, 44), wherein it is in the first position (25) in the yarn path of the yarn (7) and is driven by the yarn (7) and introduces the false twist into the yarn (7), being located in the second position (26) outside of the yarn path and not driven and wherein in at least one further position (43, 44), which is arranged between the first and the second position (25, 26), it has no contact with the thread (7) or has a smaller false twist than in the first position (25 ) in the thread (7) introduces. Method according to the previous claim, characterized in that several rollers (8) which are adjacent spinning devices (17) can be moved simultaneously and/or individually between the first, the second and the at least one further position (25, 26, 43, 44). Method according to one or more of the preceding claims, characterized in that the roller (8) together, together with the thread guide (9) and / or individually, independently of the thread guide (9) between the first, the second and the at least one other Position (25, 26, 43, 44) is moved. Method according to one or more of the preceding claims, characterized in that the roller (8) in a preparatory phase of a doffing process and/or at a speed of the spinning device (17) that is reduced compared to the operating speed, in particular at a speed of less than 10,000 revolutions/minute , into which at least one further position (43, 44) is moved. Method according to one or more of the preceding claims, characterized in that the roller (8) is arranged in the second position (26) or in the further position (44) without contact with the thread (7) during the doffing process. Method according to one or more of the preceding claims, characterized in that the roller (8) is moved into the at least one further, in particular several further positions (43, 44) depending on the operating speed of the spinning device (17). Method according to one or more of the preceding claims, characterized in that the axis of rotation (15) of the rotating roller (8) when viewed in the thread running plane (20) and / or when viewed the thread running plane (20) is arranged at an angle (a, ß) between 30° and 60° obliquely to the thread running and preferably the angle (a, ß) is changed depending on the operating speed of the spinning device (17). Device for introducing false twist into a thread (7) on a spinning machine, with a roller (8) and a holder (21) for the roller (8), the roller (8) being rotatable on the holder (21) without a motor drive, is arranged, characterized in that the holder (21) is attached to a bearing in order to be able to assume more than two positions (25, 26), the first position (25) being such that when the device is used as intended, the role (8) is arranged in the thread path of the thread (7) and the thread (7) presses against the roller (8) with a first force, as a result of which the roller (8) is driven, in the second position (26) the roller (8 ) is arranged outside the thread path and is not driven and the roller (8) has no contact with the thread (7) in at least one further position (43, 44), which is arranged between the first and the second position (25, 26). and is therefore not driven, or the thread (7) presses against the roller (8) with a second force which is less than the first force, as a result of which the roller (8) is driven. Device according to the preceding claim, characterized in that the holder (21) has a guide element (40) for the thread (7). Device according to one or more of the preceding claims, characterized in that the positions of the holder (21) by a latching device of the bearing, in particular with a cam (27) or a magnet, and/or by a stop (33, 34). Device according to one or more of the preceding claims, characterized in that the bearing is movable or immovable and has a receptacle (18) for attachment to a preferably pivotably mounted thread guide (9) or longitudinal component (23) of the spinning device (17). Spinning machine with a large number of spinning stations (1), each with a drafting system (3), a spinning device (17) and a device for introducing false twists (22) into a thread (7), with a thread running plane (20) through the largely direct top view course of the thread (7) through the drafting system (3) to the spinning device (17) and the drafting system (3) has an exit clamping point (6) with an upper roller (4) and/or a lower roller (5) on which the thread (7) leaves the drafting system (3) and between the exit clamping point (6) and the spinning device (17) a roller (8) with an axis of rotation (15) aligned obliquely to the thread running plane (20) is arranged, the running thread ( 7) rotates about its longitudinal axis when passing the roller (8) and thereby obtains a false twist and between the output nip point (6) of the pair of take-off rollers and the spinning device (17) a thread guide (9) is arranged and the roller (8) on a holder (21) is rotatably arranged without a motor drive, characterized in that the holder (21) is fixed in a bearing in order to be able to assume more than two positions (25, 26, 43, 44), the first position (25) being such that the roller (8) is arranged in the course of the thread is, deflects the thread from a straight line and is driven by the thread (7) and the second position (26) is such that the roller (8) is arranged outside the thread path and is not driven and the roller (8) in at least one further position (43, 44), which is arranged between the first and the second position (25, 26), has no contact with the thread (7) or has less contact with the thread (7) than in the first position (25) deflects from a straight course. Spinning machine according to the preceding claim, characterized in that the holder (21) or the bearing on the thread guide (9) or on a component of the spinning position, in particular on a longitudinal component (23) of the spinning machine, is arranged. Spinning machine according to one or more of the preceding claims, characterized in that the thread guide (9) or the component of the spinning position (1), in particular the longitudinal component (23) on which the holder (21) or the bearing is arranged, is designed to be rotatable is. Spinning machine according to one or more of the preceding claims, characterized in that the holder (21) and/or the thread guide with the holder (21) arranged thereon is assigned a drive for moving the roller (8) into at least one of the three positions. Spinning machine according to one or more of the preceding claims, characterized in that the axis of rotation (15) of the rotating roller (8) when viewed in the thread running plane (20) and / or when viewed from the thread running plane (20) is arranged at an angle (a, ß) between 30° and 60° at an angle to the thread running. Spinning machine according to one or more of the preceding claims, characterized in that the roller (8) is arranged in such a way that the thread (7) is raised or lowered compared to the course of the thread (7) without roller (8) in addition to the lateral deflection . Spinning machine according to one or more of the preceding claims, characterized in that the roller (8) is arranged in such a way that the thread (7) is deflected laterally out of the thread running plane (20) by the roller (8) and the thread (7) at the same time after the exit nip point (6), the upper roller (4) or the lower roller (5) is contacted in such a way that it introduces a second false twist into the thread (7).