EP3208370B1 - Device and method for determining the diameter of a thread balloon, formed by a running thread at the workstation of a textile machine - Google Patents

Description

Device and method for determining the diameter of a thread balloon formed by a running thread at a work station of a thread balloon-forming textile machine

The present invention relates to a device for determining the diameter of a thread balloon formed by a running thread at a work station of a thread balloon-forming textile machine and an associated method.

In the textile machine industry, different embodiments of production machines have been known for a long time, in which thread balloons are formed during operation in the area of their often numerous workplaces or associated operating facilities.

Such production machines therefore have monitoring devices for determining and limiting the size of these thread balloons, which can work very differently. The known monitoring devices often have, for example, sensor devices with which the rotating yarn that forms the thread balloon is observed.

In the DE 101 03 892 A1 For example, a method and a device are described with which the thread withdrawal speed of supply bobbins arranged in the creel of a warping machine is to be optimized.

As is well known, when a thread is drawn off overhead and at a relatively high draw-off speed from a supply bobbin, which is positioned in an associated gate, in the course of the work process, a thread balloon, the diameter of which depends, among other things, on the thread draw-off speed and the thread tension. The size of the thread balloon grows with increasing thread withdrawal speed.

In the case of the DE 101 03 892 A1 known method, the size of at least some of the thread balloons produced when the thread is withdrawn is detected by measuring means arranged on the gate and transmitted to a control device which, when reaching Threshold values of the thread balloons ensure that the thread take-off speed is regulated. Various optically operating measuring units are used as measuring means for detecting the size of the thread balloon, for example a camera, one or more light barriers, or similar devices.

That in the DE 101 03 892 A1 However, the method described is only used to scan the limit values for the balloon size; there is no information about the balloon size at any point in time during the process. This means that the regulation described is only activated when a given limit value is exceeded or not reached. The control is also suspended when the specified values for the maximum take-off speed or the maximum thread tension are reached.

Through the DE 22 55 663 A1 and through the EP 0 282 745 A1 In connection with ring spinning machines, optically operating measuring devices are also known with which a thread balloon shape and / or a thread balloon size can be detected.

In the DE 22 55 663 A1 For example, a workstation of a ring spinning machine is described which is equipped with an air or magnetically mounted spinning ring on which a spinning rotor rotates driven by the running thread.

Since it is known that a certain difference between the speed of the spinning ring and the speed of the spinning rotor is necessary during the operation of such workplaces in order to ensure a proper spinning process, both the speed of the air or magnetically mounted spinning ring and the speed are checked during the spinning operation of the spinneret.

Furthermore, with this method it is continuously checked whether a predetermined maximum thread tension is observed, and there is a control and, if necessary, stabilization of the thread balloon that appears in the area of the spinning head during spinning. That is, by measuring the thread curve deviation of the thread balloon from its meridian plane and correspondingly regulating the thread tension by means of variable braking of the spinning ring, the course of the thread curve of the thread balloon is stabilized. The device for detecting the thread curve deviation of the thread balloon essentially consists of a measuring transducer, which has a number of small photo elements, and a trigger device that ensures that the thread balloon is periodically flashed.

The known devices are either ( DE 22 55 663 A1 ) relatively complicated and often quite imprecise or due to their large measuring range ( DE 101 03 892 A1 ) very sensitive to air pollution.

These known devices have therefore not been able to gain acceptance in practice.

In the JP S63 126945 A describes a method and a device for setting a weft thread tension in a shuttle loom. The outermost position of the weft thread balloon is detected at at least two different positions in relation to the axial direction of the weft thread delivery section and the size of the weft thread balloon is determined from the detection result. On the basis of the calculation result, a control signal is transmitted to the drive motor 4 and the position regulation of the weft thread guide 6 is regulated in such a way that the shape of the balloon is optimized.

the EP 0 282 742 A1 deals with a method and a device for online production and quality monitoring on textile machines. Monitoring takes place by determining the diameter of a thread moving transversely to its longitudinal direction due to the formation of a thread balloon, which thread traverses a bundle of rays running between a light source and a light receiver during its transverse movement. In this case, the light receiver is shaded according to the respective thread thickness. The size and / or duration of this shadowing is evaluated as a measurement signal for the thread diameter and assessed according to known criteria for thread count, thread evenness and other criteria derived therefrom.

EP 3 168 338 A1 describes a work station of a two-for-one twisting or cabling machine, on which a balloon thread guide eyelet, which is height-adjustable by a drive, can always be positioned in an optimal operating position. A sensor device detects signals that are forwarded to a control device which, based on the diameter of the thread balloon determined from the signals, controls the drive of the balloon thread guide eyelet so that it assumes a position that limits the diameter of the thread balloon. The sensor device according to EP 3 168 338 A1 is arranged so that the measuring beam of the sensor device runs orthogonally to the axis of rotation of the spindle.

the EP 0 282 742 A1 describes a method and a device for on-line production and quality monitoring of the workstations of a multi-spindle textile machine, that is, a method and a device with which the presence of the threads and the thread diameter is monitored.

For this purpose, a ring spinning machine is equipped with an optical monitoring element which simultaneously controls a large number of the workplaces of the textile machine arranged in a row next to one another by illuminating the thread balloons rotating in the area of the workplaces.

For this purpose, the monitoring organ has a transmitter and a receiver which are designed and arranged in such a way that a beam of rays sent by a transmitter passes through the numerous circulating thread balloons on its way to the receiver and is intermittently interrupted or weakened by the thread balloons.

The shadowing is converted into an electrical signal in the receiver, which is used in an associated control device as a basis for further evaluation.

Also in the EP 0 282 742 A1 The method described works occasionally quite imprecisely, since the beam of rays on its way from the transmitter to the receiver is often negatively influenced by fiber and dust particles, which are almost unavoidable in the atmosphere of a spinning room. In addition, due to the selected arrangements of the monitoring body, it is not possible to draw any conclusions about the balloon diameter.

Furthermore, through the EP 2 419 554 B1 a work station of a two-for-one twisting and cabling machine is known, the winding and winding device of which is arranged in such a way that it lies within a thread balloon during operation.

In order to be able to control the size of the thread balloon, the work station has a monitoring device which can have different embodiments. The monitoring device can work either indirectly or optically.

The size of the thread balloon can, for example, via a thread tension sensor, which is arranged either between a thread drive device and the entry of the thread into a spindle, which ensures the creation of the thread balloon, or by means of a thread tension sensor, which is located between the exit of the thread from the spindle and a further thread drive device is positioned, can be determined indirectly.

In a further embodiment, the size of the thread balloon can also be recorded indirectly by measuring the power or the torque of the drive device of the spindle. This means that the current that is picked up by the spindle drive is determined by means of a measuring device and the size of the thread balloon is deduced from this in an evaluation device.

With regard to optical measuring devices that monitor the thread balloon encircling the winding and winding device, a first embodiment proposes the use of at least two light barriers which have a light source for emitting a light beam and a light-sensitive detector for receiving the light beam. With such a device, the interruption of the light beam by the thread of the thread balloon running past is detected during operation. However, the known embodiment is only used to scan the limit values for the balloon size and does not provide any precise information about the size of the thread balloon at any point in time during the winding process.

In a further, comparable embodiment, a light sensor of the CCD type is used in conjunction with a beam-like, stroboscopic light source, for example an LED or laser.

In the device, which operates with a light sensor and a stroboscopic light source that is synchronized with the rotation of the spindle, the image and thus the shape of the thread-balloon-forming yarn is localized when it is illuminated by the flash.

In such an embodiment, however, depending on the yarn density, yarn surface and / or yarn twist, different reflections can occur, which negatively influence the error rate and the resolution of the measurement. CCD receivers are also relatively cost-intensive devices, since they require a complex evaluation unit for their operation.

The one in the EP 2 419 554 B1 The monitoring devices described in connection with a workstation of a two-for-one twisting and cabling machine can be improved overall, since they either do not measure accurately enough or are relatively cost-intensive.

Proceeding from the prior art mentioned above, the invention is based on the object of developing a device or a method with which the diameter of a thread balloon formed by a running yarn can be determined directly and reliably. The device in question should also be as simple and inexpensive as possible in terms of its construction.

This object is achieved according to the invention in that the work station of a two-for-one twisting or cabling machine comprises a device for determining the diameter of a thread balloon formed by a running thread, the work station having an electromagnetically operating sensor device which is designed and arranged so that it can be used during of the operation of the work station, with each revolution of the thread balloon through the thread forming the thread balloon, at least two disturbances of a measuring beam of the sensor device occur and via a device for influencing the thread delivery speed of the outer thread, which is connected to a control circuit via control lines, the time interval between the disturbances of the measuring beam being detectable by the sensor device and being forwarded to the control circuit for calculating the diameter of the thread balloon, the control circuit being the device controls to influence the thread delivery speed to lead to a correction of the diameter of the rotating thread balloon, and wherein the sensor device is arranged so that the measuring beam of the sensor device either runs parallel and at a distance from the axis of rotation of the spindle or at an angle to the axis of rotation of the spindle, which is> 90 ° and <180 °.

The device according to the invention has the particular advantage that the diameter of the thread balloon is continuously monitored from an adjustable minimum balloon size at each work station of the thread balloon-forming textile machine.

Due to the design and arrangement of the sensor device according to the invention, a direct, immediate determination of the diameter of the thread balloon takes place. That is, the always directly and correctly determined thread balloon size is reliably and precisely transmitted for evaluation to a downstream device which, if necessary, initiates regulating measures, preferably in connection with the thread tension of the outer thread.

The use of a sensor device according to the invention is inexpensive and also enables a compact design of the work station, with the result that the space required for setting up a two-for-one twisting or cabling machine is reduced.

The sensor device according to the invention is not only relatively inexpensive, but also has, as already indicated above, a very high sensitivity and rapid response, so that the rotating thread balloon is always scanned quickly and reliably.

Furthermore, the sensor device can also, as by the DE 199 30 313 A1 known to have a solar cell and a feedback between the transmitter and the receiver. Such feedback compensates for possible errors due to contamination, aging, etc., which can occur in the system.

The sensor device can be designed as an optically operating light barrier which has a light source and a light receiver. Such light barriers are proven components in textile machine construction, which are used in relatively large numbers in the textile industry. This means that such components not only work very reliably during operation, but also have a very long service life. In addition, such components are also relatively inexpensive due to their large numbers.

The light barrier can either be designed as a one-way light barrier in which the light source and the light receiver are arranged on opposite sides of the thread balloon to be monitored, or it can be designed as a reflection light barrier in which the light source and the light receiver are on the same side of the to monitoring thread balloons are installed.

In the case of photoelectric retro-reflective sensors, the light source and the light receiver can either be arranged in a common sensor housing or in separate housings, although in both cases an additional reflector must be installed which, for example, is arranged on the opposite side of the thread balloon to be monitored with respect to the sensor housing and the light beam from the light source is reflected back to the light receiver.

Both embodiments of light barriers are known and have long been tried and tested in textile machine construction.

The sensor device according to the invention does not necessarily have to work optically with a measuring beam based on a light / laser beam; it is also possible to use a measuring beam that works on a different basis of the electromagnetic spectrum.

The measuring beam can, for example, also be initiated by an ultrasound, induction, heat source etc. or their interference, in which case a corresponding, associated receiver is also used.

A light-emitting diode can be used as the light source. Such diodes, known for short as LEDs in specialist circles, are characterized by high luminosity, a long service life and very low energy consumption.

In principle, however, the use of other lighting means as a light source is also conceivable in connection with the sensor device according to the invention.

A laser diode or a surface emitter = VCSEL, for example, could also be used as the light source. These illuminants also each have special advantages.

When using a light barrier, it is also advantageous if the light receiver has a receiver diode, which is designed, for example, as a photodiode. However, a phototransistor or a photoresistor can also be used as a light receiver.

It is well known that a photodiode is very sensitive to fluctuations in brightness. For example, if the light beam emitted by the light source is interrupted by a thread, the reduced illuminance is registered immediately by the photodiode. This means that the electrical conductivity of the photodiode drops, which is passed on as an electrical signal to a downstream device.

With regard to the arrangement of the sensor device according to the invention, various designs are possible. The thread balloon can be scanned, for example, orthogonally or parallel to the axis of rotation of the spindle and thus to the axis of rotation of the thread balloon. In principle, however, an arrangement of the sensor device is also possible in which the measuring beam runs neither orthogonally nor parallel to the axis of rotation of the thread balloon, but at an angle.

An advantageous embodiment is also given when the sensor device, as by the DE 195 11 527 A1 known, is arranged at the level of the coding triangle of the job and designed as a light barrier. In such a case, the deviations of the thread after the triangle or the threads directly in front of the triangle to the axis of rotation of the thread balloon provide information about a possible excess length in the cord (thread). This means that if several devices for monitoring a thread balloon are used on a spindle, not only can the balloon envelope / balloon contour be optimally determined, but in conjunction with the coding triangle, the occurrence of excess lengths can also be monitored at the same time.

According to the invention it is either provided that the sensor device is arranged such that the light beam of the sensor device runs parallel and at a distance from the axis of rotation of the spindle and thus to the axis of rotation of the thread balloon or that the sensor device is arranged so that the

The light beam of the sensor device runs at an angle to the axis of rotation of the thread balloon which is> 90 ° and <180 °.

Which of the aforementioned embodiments is ultimately used is generally determined by the respective space conditions at the work stations of the thread balloon-forming textile machine or by the type of thread / thread to be processed.

In order to exclude errors when scanning the thread balloon due to the presence of spindle parts or the inner thread, for example, and to be able to display a complete balloon shape on a downstream monitor, for example, the most suitable embodiment should be selected.

In this context, however, it is important that the line of action of the measuring beam between the light source and the light receiver does not cross the center line of the thread balloon, which is preferably formed by the axis of rotation of the thread balloon.

The invention is explained in more detail below on the basis of various exemplary embodiments shown in the drawings.

Fig. 1

schematisch, in Seitenansicht eine Arbeitsstelle einer Doppeldrahtzwimoder Kabliermaschine mit einer erfindungsgemäßen Sensoreinrichtung, die so angeordnet ist, dass der Messstrahl der Sensoreinrichtung orthogonal zur Drehachse der Spindel verläuft,

Fig. 2

schematisch, in Seitenansicht eine Arbeitsstelle einer Doppeldrahtzwirnmaschine mit einer erfindungsgemäßen Sensoreinrichtung, die ebenfalls so angeordnet ist, dass deren Messstrahl der Sensoreinrichtung orthogonal zur Drehachse der Spindel verläuft,

Fig. 3

schematisch, in Seitenansicht eine Arbeitsstelle einer Doppeldrahtzwirnoder Kabliermaschine mit einer erfindungsgemäßen Sensoreinrichtung, die so angeordnet ist, dass der Messstrahl der Sensoreinrichtung parallel zur Drehachse der Spindel verläuft,

Fig. 4

graphische Darstellung der Wirkungsweise der erfindungsgemäßen Sensoreinrichtung.

It shows:

Fig. 1

schematically, in side view, a work station of a double-wire twister or cabling machine with a sensor device according to the invention, which is arranged such that the measuring beam of the sensor device runs orthogonally to the axis of rotation of the spindle,

Fig. 2

schematically, in side view, a work station of a two-for-one twisting machine with a sensor device according to the invention, which is also arranged such that its measuring beam of the sensor device runs orthogonally to the axis of rotation of the spindle,

Fig. 3

schematically, in side view, a work station of a two-for-one twisting or cabling machine with a sensor device according to the invention, which is arranged such that the measuring beam of the sensor device runs parallel to the axis of rotation of the spindle,

Fig. 4

graphical representation of the mode of operation of the sensor device according to the invention.

In the Fig. 1 is shown schematically, in side view, a work station 1 of a two-for-one twisting or cabling machine. In the exemplary embodiment, the textile machine has a gate 4 which is usually positioned above or behind the work station 1 and which is usually used to receive a large number of supply bobbins. A so-called outer thread 5 is drawn off from one of the supply bobbins, hereinafter referred to as the first supply bobbin 7.

The work station 1 also has a spindle 2 rotatable about an axis of rotation 35, in the present exemplary embodiment a cabling spindle which is equipped with a protective pot 19 in which a second supply reel 15 is mounted.

A so-called inner thread 16 is drawn off overhead from this second supply bobbin 15 and fed to a balloon thread guide eyelet arranged above the spindle 2 or to a so-called compensation system 9. The protective pot 19, which is mounted on a rotatable thread deflecting device designed as a twisting plate 8 in the exemplary embodiment, is secured against rotation, preferably by a magnetic device (not shown). The thread deflecting device of the spindle 2 is acted upon by a spindle drive 3, which can either be a direct drive or an indirect drive.

The outer thread 5 withdrawn from the first supply bobbin 7 is fed to a controllable device 6 arranged in the thread path between the gate 4 and the spindle 2 for influencing the thread tension, with which the thread tension of the outer thread 5 can be varied if necessary.

The device 6 is connected via control lines to a control circuit 18 which regulates the thread tension applied by the device 6 to the outer thread 5 and / or the thread speed.

The adjustable thread tension applied to the outer thread 5 by the device 6 is preferably of an order of magnitude which, depending on the geometry of the spindle 2, leads to an optimization of the free thread balloon B, that is to say to a thread balloon with the smallest possible diameter, leads.

Following the device 6, the outer thread 5 runs through the spindle drive 3 in the area of the axis of rotation of the spindle drive 3 and emerges below the double plate 8 through a so-called thread outlet bore in the radial direction from the hollow axis of rotation of the spindle drive 3. The outer thread 5 then runs to the outer area of the twisting disk 8.

In the present embodiment, the outer thread 5 is deflected upwards at the edge of the double plate 8 and encircles the protective pot 19 of the spindle 2, in which the second supply bobbin 15 is positioned, forming a free thread balloon B.

A sensor device 33, which is designed as a light barrier, for example, is also arranged above the protective pot 19 of the spindle 2.

The sensor device 33 can either be designed as a one-way light barrier, as shown in the figures, in which a light source 41 and a light receiver 40 are arranged on opposite sides of the thread balloon B to be monitored, or as a reflection light barrier (not shown) , in which the light source 41 and the light receiver 40 are positioned on the same side of the thread balloon to be monitored and are arranged, for example, in a common sensor housing.

In the case of a reflection light barrier, the light beam from the light source is also reflected back to the light receiver by a reflector which is arranged on the opposite side of the thread balloon B to be monitored with respect to the sensor housing.

As can be seen, the in Fig. 1 The illustrated embodiment, the one-way light barrier is positioned so that a measuring beam 42 emitted by the light source 41 of the sensor device 33, in the present case a light beam, penetrates the area of the thread balloon B orthogonally to the axis of rotation 35 of the spindle 2 and onto an associated light receiver 40 of the sensor device 33 meets. The light receiver 40 of the sensor device 33 is also connected to a control circuit 18 via a signal line.

The sensor device 33, with which the instantaneous diameter of the thread balloon B to be monitored is determined, does not necessarily have to work as a light barrier, but can basically also work according to a different physical principle. The sensor device 33 can, for example, also work with any wavelength of the electromagnetic spectrum, e.g. radar, ultrasound, infrared, etc.

In the present exemplary embodiment, however, the sensor device 33 according to the invention is designed as an optically operating light barrier which has a light source 41 and a light receiver 40. For example, light-emitting diodes = LEDs, laser diodes or surface emitters = VCSELs can be used as the light source 41. A photodiode, a phototransistor or a photoresistor is used as the light receiver 40.

How out Fig. 1 It can also be seen that the outer thread 5 withdrawn from the first supply bobbin 7 and the inner thread 16 withdrawn from the second supply bobbin 15 are brought together in the area of a balloon thread guide eyelet or a compensation system 9, the position of the balloon thread guide eyelet or the compensation system 9 being the height of the free thread balloon B being formed certainly.

The so-called cabling point is located in the balloon thread guide loop or in the compensation system 9, in which the two threads, the outer thread 5 and the inner thread 16, converge and form a cord thread 17, for example.

Above the cabling point, a thread withdrawal device 10 is arranged, by means of which the cord thread 17 is withdrawn and fed to a winding and winding device 12 via a compensating element such as a dancer device 11.

The winding and winding device 12 has, as usual, a drive roller 13 which drives a spool 14 in a frictionally engaged manner.

The device 6 for influencing the thread tension is designed either as an electronically controlled brake or as an active delivery mechanism, it also being possible for a combination of the two aforementioned components to be used.

A godet, a serrated lock washer or a drive roller with a corresponding pressure roller, for example, are possible design variants of a delivery mechanism.

The device 6 regulates the thread tension of the outer thread 5 as a function of the diameter of the free thread balloon B, which is determined by the sensor device 33. That is, during the operation of the work station 1, a measuring beam 42 initiated by the light source 41 of the sensor device 33 is crossed twice by the running outer thread 5 forming the rotating thread balloon B with each revolution of the thread balloon B, which is immediately indicated by the light receiver 40 of the sensor device 33 Disturbance S is recognized in the form of a shadowing and passed on to the control circuit 18 as an electrical signal i.

From the time interval between the two disturbances S and thus the electrical signals i generated by the light receiver 40 of the sensor device 33 with each revolution of the thread balloon B, the control circuit 18 then immediately determines the current diameter of the thread balloon B. Immediately regulating the thread delivery speed of the outer thread 5 via the device 6, which immediately leads to a correction of the diameter of the rotating thread balloon B.

As already indicated above, is in the Fig. 1 The illustrated embodiment, the sensor device 33 is designed as a light barrier, more precisely as a one-way light barrier. That is, the sensor device 33 has a light source 41 and a light receiver 40 arranged on the opposite side of the thread balloon B to be monitored, the light source 41 and the light receiver 40 being arranged in such a way that an emanating from the light source 41 serves as a measuring beam 42 Light beam penetrates the rotating thread balloon B.

The measuring beam 42 of the sensor device 33 runs orthogonally to the axis of rotation of the thread balloon B, so that the thread balloon B, which in the present embodiment is formed by the outer thread 5, intersects the measuring beam 42 twice with each revolution. The measuring beam 42 is interrupted or weakened, which leads to a different irradiation intensity at the light receiver 40 with the consequence of a change in its voltage.

In the Fig. 2 The workstation 20 of a two-for-one twisting machine shown as an exemplary embodiment has long been known in its basic structure and, for example, in the EP 2 315 864 B1 described in relative detail.

As can be seen, the work station 20 has a twisting spindle 22 which, driven by a spindle drive 23, can be rotated about an axis of rotation 35. The twisting spindle 22 has a protective pot 34 in which there is a supply bobbin 21, from which a thread 25 is drawn off by means of a thread tension influencing device 26. The thread tension influencing device 26 is connected to a control circuit 33 via a control line. The thread 25 then reaches a balloon thread guide eyelet 27, which is arranged above the thread tension influencing device 26, via a thread deflecting device 24, preferably designed as a twin plate, which is connected to a spindle drive 23. A thread take-off device 28, a compensating element, such as a dancer device 29, and a winding and winding device 30 are attached to the balloon thread guide eyelet 27. The winding and winding device 30 has, as usual, a drive roller 32 which drives a spool 31 in a frictionally engaged manner.

The work station 20 also has a sensor device 33, which in the exemplary embodiment is designed as a one-way light barrier and has a light source 41 and a light receiver 40, the light receiver 40 being connected to a control circuit 33 via a signal line.

The light source 41 and the light receiver 40 of the sensor device 33 are arranged in such a way that the measuring beam 42 initiated by the light source 41 of the sensor device 33 and present as a light beam runs orthogonally to the axis of rotation 35 of the twisting spindle 22 and thus also orthogonally to the axis of rotation of the thread balloon B.

The measuring beam 42 of the sensor device 33 is consequently crossed twice by the thread 25 with each revolution of the thread balloon B, which is immediately detected as a disturbance by the light receiver 40 of the sensor device 33 and passed on as an electrical signal i to the control circuit 33.

That is, even with the sensor device 33 of the present work station 20 of a two-for-one twining machine, any interruption or weakening of the measuring beam 42 of the sensor device 33, which is designed as a light beam, leads to a different irradiation intensity at the light receiver 40, with the result that the light receiver 40 immediately sends an electrical signal i generated, which is forwarded to the control loop 33 via the signal line. The control circuit 33 then immediately initiates regulation of the diameter of the thread balloon B via the thread tension influencing device 26.

In the Fig. 3 Workstation 2 of a two-for-one twisting or cabling machine shown as an exemplary embodiment essentially corresponds to the exemplary embodiment in FIG Fig. 1 . Job 2 according to Fig. 3 differs only in the arrangement of the sensor device 33.

As can be seen, the sensor device 33, which is also designed as a one-way light barrier in the present exemplary embodiment, is arranged in such a way that the measuring beam 42 of the sensor device 33 runs parallel to the axis of rotation 35 of the spindle 2. That is to say, the light source 41 and the light receiver 40 are positioned in such a way that the measuring beam 42 designed as a light beam is arranged parallel to the axis of rotation of the thread balloon B.

In this embodiment, too, the light beam 42 of the sensor device 33 is disturbed or weakened with each revolution of the thread balloon B by the rotating yarn, in the present case by the outer thread 5, and thereby generates different irradiation intensities on the light receiver 40, which leads to a disturbance S and thus leads to a change in the electrical voltage of the light receiver 40 and is passed on to the control circuit 18 as an electrical signal.

the Figures 4A and 4B show a graphic representation of the mode of operation of a sensor device 33 according to the invention.

In the embodiment according to Fig. 4A the sensor device 33 is designed as a one-way light barrier which, as can be seen, has a light source 41 - for example an LED or a laser - and has a light receiver 40, for example a receiver diode. The light source 41 and the light receiver 40 are arranged in such a way that a measuring beam 42 emitted by the light source 41, in the present exemplary embodiment a light beam, is disturbed by the thread forming the thread balloon B, for example an outer thread 5, with each revolution of a thread balloon B which leads to a measuring pulse at the light receiver 40, which is passed on to a control circuit 18 as an electrical signal i.

The minimum diameter of the thread balloon B that can be measured with the sensor device 33 according to the invention is given if the measuring beam 42 is only disturbed once during one revolution of the thread balloon B and the light receiver 40 only generates an electrical signal i = measuring pulse per revolution of the thread balloon B.

As the thread balloon B increases, it occurs, as in Fig. 4A shown, with each revolution of the thread balloon B through the thread 5 to two temporally spaced disturbances S of the measuring beam 42, which is detected by the light receiver 40 and forwarded by this as a measuring pulse i to the control circuit 18.

How out Fig. 4B As can be seen, the control circuit 18 easily calculates the current diameter of the thread balloon B from the time interval t between the two measurement pulses i, the known distance between the measurement beam 42 and the axis of rotation 35 of the spindle 2.

As in Fig. 4A shown, a measuring beam 42 emitted by the light source 41 of the sensor device 33 is _{disturbed twice by a thread 5, which encircles the protective cup 19 of a spindle 2 as a thread balloon B 1} and has a relatively small diameter, which is caused by the interference points S ₁ and S ₂ is marked.

_{A time span t 1} lies between the interference points S ₁ and S ₂ , which are each recognized by the light receiver 40 and passed on as an electrical signal i to the control circuit 18. The control circuit 18 then uses this and other known data, as already explained above, to immediately calculate the instantaneous diameter of the thread balloon B ₁ .

Comparable conditions are also given when the spindle 2 is encircled by a thread balloon B which has a significantly larger diameter, that is, when a thread balloon B ₂ or a thread balloon B ₃ is present.

In such a case, too, the thread 5 initiates two temporally spaced disturbances of the measuring beam 42 of the sensor device 33 with each revolution of the thread balloon Fig. 4A the interfering points relating to the thread balloon B ₂ are marked with S ₃ and S ₄ , while the interfering points _{relating to the thread balloon B 3} have the marking S ₅ and S ₆ .

As in Fig. 4B shown, the interference points S ₃ and S _{4 are} at a temporary distance t ₂ , while the interference points S ₅ and S ₆ are spaced apart by the time interval t _3. The instantaneous diameters of the thread balloons B ₂ and B _{3 can be} calculated without problems from the distances t ₂ and t _{3 by means of further known data.}

A special case is given when the measuring beam 42 of the sensor device 33 only touches the thread balloon B, that is, if only one interruption occurs per rotation of the thread balloon B.

In such a case, too, the control loop 18 can easily determine the instantaneous diameter of the thread balloon B on the basis of the known arrangement of the sensor device 33.

The device according to the invention and the associated method can advantageously also be used in connection with a reference spindle.

That is, at least one of the work stations of the thread balloon-forming textile machine is designed as a reference spindle, which is equipped with a device according to the invention and continuously monitors the diameter of the thread balloon.

The values determined by the reference spindle are then used to set the neighboring workplaces of the textile machine.

Claims (3)

1. A workstation (1) of a two-for-one twisting or cabling machine, comprising an apparatus for determining the diameter of a thread balloon (B) formed by a running thread, the workstation (1) having an electromagnetically operating sensor device (33), which is designed and disposed such that, for each revolution of the thread balloon (B) during the operation of the workstation (1), at least two disruptions (S) of a measurement beam (42) of the sensor device (33) are caused by the running thread (5, 25) forming the thread balloon (B), and the workstation (1) having a device (6) for influencing the thread delivery speed of the outer thread (5), which device (6) is connected to a control circuit (18) by means of control lines,

   in which the time interval (t) between the disruptions (S) of the measurement beam (42) can be sensed by means of the sensor device (33) and can be forwarded to the control circuit (18) for the calculation of the diameter of the thread balloon (B),

   in which the control circuit (18) controls the device (6) for influencing the thread delivery speed in order to correct the diameter of the revolving thread balloon, and

   in which the sensor device (33) is disposed such that the measurement beam (42) of the sensor device (33) either runs parallel to and at a distance from the axis of rotation (35) of the spindle (2) or runs at an angle (β) to the axis of rotation (35) of the spindle (2), the angle (β) being greater than 90° and less than 180°.
2. A method for determining and correcting the diameter (D) of a thread balloon (B) formed by a running thread (5, 25), at a workstation (1) of a two-for-one twisting or cabling machine according to claim 1, in which, as a result of the running thread (5, 25), an intermittent disruption (S) of the measurement beam (42) of the sensor device (33) caused during each revolution of the thread balloon (B) is sensed by the sensor device (33) during the operation of the workstation (1), and the workstation (1) has a device (6) for influencing the thread delivery speed, which device (6) is connected to a control circuit (18) by means of control lines,
   characterised in that

   the disruptions (S) of the measurement beam (42) of the sensor device (33) are each converted into an electrical signal (i),

   in that the time interval between the generated signals (i) is forwarded to the control circuit (18) for the determination of the diameter of the thread balloon (B), and

   in that, in order to correct the diameter of the thread balloon (B), the device (6) is controlled by means of the control circuit (18) such that the thread delivery speed is controlled.
3. The method according to claim 2, characterised in that a lack of electrical signals (i) during the operation of the workstation (1) is interpreted as a missing thread balloon (B) at the workstation (1) and thus as a thread break.

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