EP2573238B1 - Spinning machine and method for interrupting the production of thread on a spinning machine - Google Patents

Description

The present invention relates to a method for interrupting the production of yarn on a spinning machine, wherein the spinning machine has at least one spinning station with an input for a fiber material and an output for the yarn made of the fiber material, and wherein the spinning machine a delivery device for the supply of the fiber material in the spinning station, a take-off device for the withdrawal of the yarn from the spinning station, a winding device for winding the produced yarn and a yarn monitoring unit for monitoring at least one yarn parameter (eg in the form of the yarn thickness or other parameter representative of the quality of the yarn), wherein the yarn production upon detection of a defined deviation of the monitored Garnparameters is interrupted by a target value in a bobbin change on the winding device and / or before switching off the spinning machine. In addition, a spinning machine is proposed for producing a yarn, wherein the spinning machine has at least one spinning station with an inlet for a fiber material and an outlet for the yarn made of the fiber material, and wherein the spinning machine has a delivery device for feeding the fiber material into the spinning station, a withdrawal device for the withdrawal of the yarn from the spinning station, a winding device for winding the yarn produced and a yarn monitoring unit for monitoring at least one yarn parameter.

In general, it is known, for example in rotor or air-jet spinning machines, to stop the spinning process in the event of a detected yarn defect by interrupting the fiber feed. The winding-side yarn end is finally wound up by the revolving spool while the yarn end separated therefrom is sucked off. For the subsequent re-spinning finally has to be located on the spool yarn, z. B. be solved with the help of a corresponding suction device, from the bobbin surface in order to be able to feed it again against the actual spinning direction of the spinning station. The finding of the yarn end, however, usually turns out to be quite time-consuming and is moreover of use effect, especially with very fine and highly twisted yarns, so that the piecing process can lead to a significant delay in the further spinning process.

DE 3 205 535 A1 shows an existing state of the art.

Object of the present invention is therefore to accelerate the piecing after a controlled interruption of yarn production.

The object is solved with the features of the independent claims.

According to the invention, the method is characterized in that, to interrupt the yarn production, the conveying speeds of the delivery device, the removal device and the winding device are gradually reduced to their standstill, wherein the reduction takes place such that the end of the yarn produced after completion of the reduction within the Spinning station is located. In contrast to the method described above, in which the yarn end produced until the spinning stop is inevitably wound onto the bobbin because it can not be stopped abruptly due to its inertia, such winding can be effectively prevented by the method according to the invention. The operated spinning machine is preferably an air spinning or rotor spinning machine. Both types of spinning machine are characterized by the fact that certain conditions with regard to the conveying speeds of the delivery device and the withdrawal device must be observed for the desired yarn production. Thus, these have to exceed certain limits for the production of a high-quality yarn in order to allow the desired inside the spinning chamber swirl distribution of the fiber material. Now become the mentioned conveyor speeds gradually, ie preferably within a few seconds throttled, so finally reaches the point at which no more yarn production takes place because either too little fiber material transported into the spinning chamber or the yarn in relation to the supply of the fiber material is withdrawn too quickly from the spinning chamber. At this time, finally, a yarn end is formed, which moves in the direction of the winding device in accordance with the remaining conveying speed of the drawing-off device. According to the invention it is now provided that the conveyor speeds are finally reduced to zero in the context of the interruption of yarn production in such a way that the yarn end is within the spinning station after the standstill of the individual conveyors. It is therefore intended to cancel the yarn formation within the spinning station by gradual and thus not abrupt throttling of the individual conveyor speeds. The corresponding yarn end is thus created by appropriate adaptation of the individual conveyor speeds. In this case, the yarn production is stopped so that the yarn separates from the subsequent fiber material (it may be necessary to completely detach the yarn from the fiber material, the delivery device and / or the trigger device, especially during the reduction of the corresponding conveyor speeds, to accelerate or to decelerate more intensely to effect complete stripping of the yarn). Since the conveying speeds are already significantly lower at this point than during the actual yarn production, finally, the winding device can be specifically slowed down, so that a defined final state is formed, in which the end of the yarn at the position described - and thus not on the surface a corresponding coil of the winding device - is located. In order to ensure a uniform winding of the yarn produced on the bobbin even at reduced conveying speeds, it may additionally be advisable to slow down (or to stop centrally) any device for traversing the yarn. Subsequently, the yarn end can now be prepared for further piecing or provided for the corresponding piecing Be moved without previously a yarn end search on a coil surface would be necessary. The same applies analogously to rotor spinning machines, for example, where yarn production is also interrupted if the corresponding conveying speeds fall below certain limit values.

It is also advantageous if the delivery device is formed by a delivery roller pair and / or the removal device by a pair of take-off rollers. Such rollers allow precise control of the respective conveyor speeds by adjusting their speeds. The speeds can thus be reduced within the scope of the inventive method within a predetermined period of time, which is usually between one and several seconds, without causing a tearing of the yarn.

It is likewise advantageous if the spinning station has an air swirl chamber and a hollow spinneret projecting into the air swirling chamber, through which the produced yarn is withdrawn from the air swirling chamber during yarn production in the direction of the exit of the spinning station, and the conveying speeds are reduced such that the end of the manufactured yarn is inside the spinneret after completion of the reduction. The yarn end need not be threaded in this case contrary to the actual spinning direction in the spinneret, so that a large part of the necessary Fadenhandhabungs- and thread guide work, which are necessary in the prior art before the piecing, omitted. The yarn end now only has to be moved (for example, pushed or sucked) counter to the spinning direction so that the yarn end, possibly prepared for piecing in an intermediate step, can be brought into contact with the subsequent fiber material. The actual piecing process, ie the connection of fiber material and yarn end, can finally be done in a conventional manner.

It is also extremely advantageous if the conveying speeds are reduced continuously, preferably linearly. This avoids abrupt changes in speed and possible tearing of the yarn. In addition to a linear speed reduction is of course also any deviating reduction conceivable. Although it is quite possible to simultaneously reduce the delivery speeds of the delivery device and the withdrawal device or to stop said devices at the same time, it has proven to be advantageous to reduce the respective delivery rates over time. For example, it is advantageous to throttle the conveying speed of the delivery device before reducing the conveying speed of the discharge device. It is also advantageous to stop the discharge device after the delivery device has stopped, in order to ensure that the end of the yarn produced is located at the position of the spinning machine according to the invention. As a result, it is thus advantageous if the drives of the delivery device and the withdrawal device can be controlled separately.

It should also be noted at this point in general that it may be advantageous to change the air pressure prevailing in the spinning station (or individual regions thereof) or the air pressure of introduced air during or even before the interruption of the yarn production, to the pressure conditions adapt to the appropriate conveying speeds. For example, in the case of an air-spinning machine, it would be conceivable to reduce (or increase) the air pressure of the air introduced into the swirl chamber of the respective spinning station during the interruption of the yarn production compared to the pressure during the yarn production. Similarly, the negative pressure prevailing during spinning in the spinning rotor surrounding spinning chamber of a rotor spinning machine, during or before the interruption of the yarn production could be changed accordingly to prevent excessive turning of the present in the spinning chamber yarn end.

It is likewise advantageous if the withdrawal device comes to a standstill in time after the delivery device. In this way, after the termination of the yarn production, a defined distance is created between the yarn end and the previously stopped fiber material, whereby in the case of an air-spinning machine it can be prevented that fiber material enters the spinneret together with the yarn end. Thus, one obtains a defined and clearly separated from the fiber material yarn end, which is finally available for re-piecing available.

It is also extremely advantageous if the yarn is fixed after completion of the reduction of the conveying speeds by means of a yarn store. A yarn storage device has, for example, a hollow cylinder which is connected to a vacuum source in such a way that a vacuum can be generated in the hollow cylinder as required (for example by targeted delivery of the vacuum source). Now, if the trigger device is stopped later than the winding device, so after the stop of the winding device withdrawn from the place of meaning yarn can be sucked into the hollow cylinder and thus held at a defined position, just enough yarn is sucked in that the end of the yarn on the position according to the invention is positioned within the spinning station. After the interruption of the yarn production finally starts the piecing process, in which case the yarn end must be moved against the actual spinning direction in the rule, in order to be tangible by a service robot, which takes over the piecing process. As an alternative or in addition to the fixation with the aid of the yarn store, it is of course also possible to use other fixing devices, for example a gripping device.

It is also advantageous if the trigger device comes to a standstill after the winding device. This makes it possible, for example, that the portion of the yarn which is generated during the reduction of the conveying speed, is not wound on the bobbin of the winding device. Finally, this section should be removed before re-spinning Finally, a corresponding unwinding process from the spool is eliminated. Rather, it would be conceivable, for example, to temporarily store the mentioned section within a separate yarn store and to remove it before the actual piecing process.

Advantages, however, can also bring with it when the trigger device and the winding device come to a standstill at the same time. In this case, the yarn finally runs without deflections from the spinning station to the winding device. For the piecing process, it is therefore expedient first to operate the extraction device and also the winding device in such a way that the yarn end is moved counter to the actual spinning direction. Finally, if the yarn end is outside the spinning station or the twisting agent of the same (for example outside the spinning nozzle of an air spinning machine), the piecing process can finally be started.

It is also advantageous if the yarn is fixed after completion of the reduction of the conveying speeds by means of the take-off device. If these are suitable take-off rolls, then the yarn can be reliably clamped between the respective corresponding rolls. For this purpose, it is only necessary to stop the take-off rolls as soon as the end of the yarn is inside the spinning station. If the yarn end is finally grasped manually or automatically for piecing, the clamping is released and the yarn end is released again, whereby before the release a (renewed) defined conveying of the yarn end can take place through the draw-off rolls in or against the spinning direction.

It is particularly advantageous if the end of the yarn produced moves after the interruption of the yarn production in an area between the input of the spinning station and the delivery device or in a region between the delivery device and a pair of rollers of a drafting and then during a piecing with the fiber material is connected. For this purpose, the robot comprises corresponding yarn handling devices, such as a gripping device and / or corresponding suction or blowing devices, in order to guide the yarn end against the actual spinning direction into the region in which the actual piecing process is to take place, which can likewise be carried out with the aid of the robot , Of course, it is also possible to equip the individual spinning stations with individual yarn spinning devices, each of which is separately assigned to the spinning stations, so that the use of a robot may possibly be dispensed with. Finally, it is also conceivable not to connect the end of the yarn produced in the context of a piecing with the fiber material supplied to the spinning station, but rather to use to form a Fadenendfixierung (in which the yarn end at a certain point of the full bobbin - usually at the lateral edge - is filed). To make it difficult to accidentally loosen the corresponding yarn end during the reel transport, the yarn can be unwound from the full bobbin before depositing it. The unwound section is finally wound several times around the previously unresolved side part of the spool core of the full spool and then guided back onto the spool surface and deposited there laterally.

Furthermore, it is advantageous if the piecing process takes place outside the spinning station, in particular between the delivery device and a roller pair of a drafting system. In this area, the fiber material to be spun is usually fixed after standstill of the delivery device, for example by means of corresponding delivery rollers, or in the case of an air-spinning machine, a pair of rollers of an upstream drafting system. Since contact between the fiber material and the returned yarn end must be produced during piecing, it is therefore advisable to carry out the piecing process in this area.

It is advantageous if at least the yarn section produced during the reduction of the conveying speeds is removed before the piecing process. In general, namely, the yarn that is produced during the reduction of the individual conveying speeds, have a reduced yarn quality. If the interruption of the yarn production is due to the detection of a yarn defect, it should also be ensured that the portion containing the yarn defect detected by the monitoring unit is also removed. In this case, therefore, the length of the yarn section to be removed corresponds at least to the length of the yarn which, after the interruption of the yarn production, is between the yarn end produced and the yarn defect. Finally, for removal, it may be necessary to operate the winding device before piecing so that the already wound yarn is unwound until the bobbin contains only yarn that produces before reducing the conveying speeds (or before the appearance of the yarn defect) has been. It would also be possible to temporarily store the low-quality yarn in the yarn store described above and to separate it off before the piecing process. For this purpose, z. B. come a separate cutter used. Finally, it should be noted at this point that it can also bring advantages if a relatively thick yarn is produced directly before the interruption of the yarn production according to the invention. This can then be found and / or taken by the robot particularly quickly and reliably.

Furthermore, there may be advantages if the reduction of the conveying speeds in dependence on physical and / or chemical properties of the fiber material (type of fiber material, strength, staple length, etc.) and / or characteristics of the spinning machine, in order to optimally to the respective conditions to be able to enter. The parameters of the spinning machine can include individual speeds, delivery speeds or corresponding parameters of the drafting system used. Likewise, humidity and / or temperature values can be defined Spaces of the spinning machine or even the spinning machine surrounding premises are taken into account.

Not least, it is advantageous if the end of the yarn produced after completion of the reduction of the conveying speeds, in particular by means of a vacuum source, is kept within the spinning station. The holding or fixing of the yarn end has the advantage that this is in the desired position until the next process step of the piecing process (which could also be monitored with a sensor if necessary).

Finally, the spinning machine according to the invention is characterized in that it has a control and / or regulating unit which is designed to operate the spinning machine according to one or more aspects of the preceding description, wherein the interruption of the yarn production at individual or even at all spinning stations the spinning machine can be done in the manner according to the invention. With regard to the respective advantages and possible modifications, reference is made to the previous description.

Finally, further process steps or features of the spinning machine can be realized, resulting in an advantageous demarcation from the known prior art.

For example, it would be conceivable that in the event of a yarn breakage (ie, an interruption of the spinning process, which was initiated in a controlled or uncontrolled manner) yarn handling devices are used which can grip the yarn end possibly wound on the bobbin of the corresponding winding device and feed it to the subsequent piecing process. In this case, the yarn handling devices can be assigned to be part of a service robot patrolling between the respective spinning stations or also individually assigned to each spinning station. Likewise, it is conceivable the individual Equip spinning stations with appropriate Garnhandhabungseinrichtungen and yet use one or more service robots, thereby achieving a certain division of labor.

A further possibility of optimizing the method according to the invention or the spinning machine described would be achieved by designing the method for interrupting yarn production "self-learning". For example, it would be conceivable that the individual parameters (amount and beginning of the reduction of the respective conveying speeds, time of stopping the delivery device, the withdrawal device and / or the winding device, characteristics of the piecing process, etc.) depend on the data supplied by the corresponding sensors be adjusted in a preferably continuous and carried out by the control and or regulating device of the spinning machine process.

Figur 1

eine Seitenansicht eines Ausschnitts einer erfindungsgemäßen Spinnmaschine während der Garnherstellung, und

Figur 2

eine Seitenansicht eines Ausschnitts einer erfindungsgemäßen Spinnmaschine nach der Unterbrechung der Garnherstellung.

Further advantages of the invention are described in the following exemplary embodiments. Show it:

FIG. 1

a side view of a section of a spinning machine according to the invention during yarn production, and

FIG. 2

a side view of a section of a spinning machine according to the invention after the interruption of the yarn production.

FIG. 1 shows a schematic view of a section of an air-jet spinning machine according to the invention. As a rule, the air-spinning machine comprises a drafting system 16, which is supplied with a fiber material 3, for example in the form of a relined conveyor belt. Furthermore, the air spinning machine shown in principle comprises a spaced apart from the drafting 16 spinning station 1 with an inlet 2 for the fiber material 3 and an internal air vortex chamber fourteenth

The fiber material 3 is introduced into the spinning station 1 by means of a delivery device 6 designed as a delivery roller pair 11, which in turn can be part of the drafting system 16. Finally, within the air vortex chamber 14, the fiber material 3 or at least a part of the fibers of the fiber material 3 is provided with a rotation in order to produce the desired yarn 5. The rotation is produced by a targeted air flow in the region of a spindle 17, wherein the air flow is generated by not shown, tangentially opening into the air vortex chamber 14 nozzles.

Furthermore, the spinning machine shown comprises a take-off device 7 formed by a take-off roller pair 12 and a winding device 8 connected downstream of the take-off roller pair 12 for the yarn 5 withdrawn from the spinning station 1 through the exit 4.

Finally, the spinning machine is equipped with a yarn monitoring unit 9 which monitors previously defined parameters of the yarn 5 (eg yarn thickness, yarn tenacity or other parameters representative of the quality of the yarn 5). The yarn monitoring unit 9 preferably operates without contact.

The device according to the invention need not necessarily have a drafting device 16, as shown in FIG FIG. 1 is shown. Also, the pair of take-off rollers 12 is not mandatory. In addition, the spinning machine according to the invention may also be designed as a rotor spinning machine, wherein the spinning station 1 in this case has a rotor instead of the spindle 17 shown, through which the yarn 5 produced at the tip of the spindle 17 is withdrawn from the spinning station 1.

The inventive method for interrupting the yarn production is now from the synopsis of FIGS. 1 and 2 seen. First, the shows FIG. 1 the course of the fiber material 3 and in the spindle 17 produced yarns 5 during the actual spinning process.

If, with the aid of the yarn monitoring unit 9 (which can also be positioned elsewhere), a defined deviation of the monitored yarn parameter from corresponding nominal values is detected or a bobbin change occurs, the conveying speeds of the delivery device 6, the discharge device 7 and the winding device 8 become gradually reduced. Likewise, the reduction can be done before the spinning machine is turned off.

The reduction need not be simultaneous or continuous. In any case, however, the respective conveying speeds should be throttled so that the spinning process can be maintained as long as possible. Tearing of the yarn 5, as common in the art, can be eliminated in this way. Rather, it is the goal of reducing the conveyor speeds that the stable spinning process collapses by falling below defined conveyor speeds and thus at a certain time no yarn 5 is more produced from the fiber material 3. At this point in time, it finally comes to the desired interruption of yarn production, in which the yarn 5 dissolves from the fiber material 3 without separate force. This can be achieved, for example, by reducing the conveying speed of the delivery device 6 to such an extent that it no longer supplies a sufficient quantity of fiber material 3 in order to form a yarn 5 therefrom. It is also possible to slow down the conveying speed of the take-off roller pair 12 slower (or even faster, if required) than the conveying speed of the delivery roller pair 11 and / or the winding device 8.

After the yarn production has been stopped, it is finally possible to operate the pair of withdrawal rollers 12 for a small period of time, so that the resulting end 10 of the yarn 5 after the final shutdown of the delivery device 6, the discharge device 7 and the winding device. 8 occupy a position as in FIG. 2 is shown. A part of the produced yarn 5 can in this case only in FIG. 2 The yarn storage 13 (eg, in the form of a tube connected to a vacuum source) may be held to prevent the yarn 5 produced during the reduction of the conveying speeds from being wound onto the winding device 8 (the yarn store 13 is of course not true to scale, but only shown schematically).

As a result, the necessary for the piecing process end 10 of the yarn 5 is now at a defined location within the spinning station 1, so that the piecing can be started without previously the end 10 of the yarn 5, z. B. on the surface of a coil 18 of the winding device 8, would have to be sought (as is common in the prior art).

For the piecing process, the end 10 of the yarn 5 is finally with the help of a service robot, a spinning yarn own Garnharidhabungseinrichtung or manually against the actual spinning direction in the air vortex chamber 14, between the input 2 of the spinning station 1 and the delivery device 6 or between the delivery device 6 and an adjacent Roller pair 15 of the drafting 16 shifted. There it can be brought into contact with the fiber material 3 and introduced again into the spinning station 1. The spinning process finally starts again.

Incidentally, the invention is not limited to the illustrated embodiments. Rather, all combinations of the individual features described, as shown or described in the claims, the description and the figures and as far as a corresponding combination is technically possible or seems reasonable, the subject of the invention.

Thus, the yarn 5 after the interruption of the yarn production, as well as in the FIGS. 1 and 2 shown, additionally or alternatively to the yarn storage 13 by means of the pair of take-off rollers 12 are fixed. This can through Direction reversal also serve to move the end 10 of the yarn 5 before piecing against the spinning direction. Likewise, a cutting and / or disposal device 19 may be arranged between the drafting system 16 and the spinning station 1 or even at the spinning station 1 itself, with the aid of which the end 10 of the yarn 5 can be prepared accordingly before piecing. In this case, a portion of the yarn 5 is usually cut off and disposed of, for example by means of negative pressure on the cutting and / or disposal device 19, which also acts as a suction device in this case.

LIST OF REFERENCE NUMBERS

1

spinning unit

2

entrance

3

fiber material

4

output

5

yarn

6

Supply means

7

off device

8th

spooling device

9

Garnüberwachungseinheit

10

End of the manufactured yarn

11

Pair of delivery rollers

12

Off rollers

13

yarn store

14

Air swirl chamber

15

Roller pair of a drafting system

16

drafting system

17

spindle

18

Kitchen sink

19

Cutting and / or disposal facility

Claims (15)

1. A method for interrupting yarn production on a spinning machine, the spinning machine comprising at least one spinning point (1) having an inlet (2) for a fiber material (3) and an outlet (4) for the yarn (5) made from the fiber material (3), and the spinning machine comprising a delivery device (6) for feeding the fiber material (3) into the spinning point (1), a take-off device (7) for drawing off the yarn (5) out of the spinning point (1), a winding device (8) for winding up the produced yarn (5), and a yarn monitoring unit (9) for monitoring at least one yarn parameter, the yarn production being interrupted upon detecting a defined deviation of the monitored yarn parameter from a target value, upon changing bobbins at the winding device (8), and/or prior to switching off the spinning machine, characterized in that the feed speeds of the delivery device (6), the take-off device (7), and the winding device (8) are gradually reduced to a stop in order to interrupt the yarn production, wherein the reducing takes place such that the end of the produced yarn (5) is located within the spinning point (1) after the reducing is completed.
2. The method according to the preceding claim, characterized in that the delivery device (6) is formed by a delivery roller pair (11) and/or the take-off device (7) is formed by a take-off roller pair (12).
3. The method according to one or more of the preceding claims, characterized in that the spinning point (1) comprises an vortex chamber (14) and a hollow spindle (17) protruding into the vortex chamber (14), through which the produced yarn (5) is drawn off out of the vortex chamber (14) in the direction of the outlet (4) of the spinning point (1) during yarn production, and that the reducing of the feed speeds takes place such that the end (10) of the produced yarn (5) is located within (4) the spindle (17) after the reducing is complete.
4. The method according to one or more of the preceding claims, characterized in that the feed speeds are reduced continuously, preferably linearly.
5. The method according to one or more of the preceding claims, characterized in that the take-off device (7) comes to a stop after the delivery device (6).
6. The method according to one or more of the preceding claims, characterized in that the yarn (5) is fixed by means of a yarn storage (13) after the reducing of the feed speeds is completed.
7. The method according to one or more of the preceding claims, characterized in that the take-off device (7) comes to a stop after the winding device (8).
8. The method according to one or more of the claims 1 through 6, characterized in that the take-off device (7) and the winding device (8) come to a stop at the same time.
9. The method according to one or more of the preceding claims, characterized in that the yarn (5) is fixed by means of the take-off device (7) after the reducing of the feed speeds is completed.
10. The method according to one or more of the preceding claims, characterized in that the end (10) of the produced yarn (5) is moved into an area between the inlet (2) of the spinning point (1) and the delivery device (6) or into an area between the delivery device (6) and a roller pair (15) of a drawing unit (16) after interrupting yarn production, and is then connected to the fiber material (3) during a piecing process.
11. The method according to the preceding claim, characterized in that the piecing process takes place outside of the spinning point (1), particularly between the delivery device (6) and a roller pair (15) of a drawing unit (16).
12. The method according to the preceding claim, characterized in that prior to the piecing process, at least the yarn segment produced during the reduction of the feed speeds is removed.
13. The method according to one or more of the preceding claims, characterized in that the reduction in feed speeds takes place as a function of physical and/or chemical properties of the fiber material (3) and/or key parameters of the spinning machine.
14. The method according to one or more of the preceding claims, characterized in that the end (10) of the produced yarn (5) is retained within the spinning point (1) after the reducing of the feed speeds is completed, particularly by means of a vacuum source.
15. A spinning machine for producing a yarn (5), the spinning machine comprising at least one spinning point (1) having an inlet (2) for a fiber material (3) and an outlet (4) for the yarn (5) made from the fiber material (3), and the spinning machine comprising a delivery device (6) for feeding the fiber material (3) into the spinning point (1), a take-off device (7) for drawing off the yarn (5) out of the spinning point (1), a winding device (8) for winding up the produced yarn (5), and a yarn monitoring unit (9) for monitoring at least one yarn parameter, characterized in that the machine comprises a control and/or regulation unit designed for operating the spinning machine according to one or more of the preceding claims.

Images