EP3492640B1 - Method for control of the delivery of yarns of a system comprising a plurality of yarn feeders and textile machine with a system having a plurality of yarn feeders - Google Patents

Description

The invention relates to a method for controlling the delivery of threads of a system with several thread delivery devices with a predetermined thread tension to workplaces of a textile machine and a textile machine with a corresponding system.

A method for delivering threads to a textile machine for operating thread delivery devices is known from US Pat DE 102 34 545 B4 known. The thread delivery devices are operated in a test phase with matching target tensions in a tension-controlled manner, with the delivered thread quantities being recorded. After the trial phase, the thread delivery devices are regulated or controlled based on a thread quantity specification determined from the detected thread quantities.

In the EP 2 067 886 B1 describes a method for feeding a plurality of yarns to a textile machine, in which the feed takes place with a constant feed length of the yarn. Delivery devices are arranged to keep the tension of the respective yarn at a predetermined value. In one example, a control unit of one of the delivery devices controls the control and regulation of the voltage of all other delivery devices.

A method for controlling the thread delivery from a thread delivery device to a textile machine, wherein the thread is withdrawn from a storage body of the thread delivery device, is shown in US Pat DE 10 2013 113 115 B4 known. Such yarn delivery devices are also referred to as storage yarn delivery devices. The thread tension of the thread is adjusted by a braking device in the thread course after the storage body with the help of an adjusting device. For this purpose, a brake signal, namely an operating current, is set for the setting device. Specific data are stored in a data unit for the thread delivery device, values of the working current being assigned to values of the thread tension to determine the specific data.

From the DE 10 2014 118 743 A1 and from the DE 10 2015 118 027 B3 Thread delivery devices are known, each having a thread tension unit for regulating the thread tension to a reference value of the thread tension.

From the DE 100 05 101 A1 is a method for producing a knitted or knitted fabric from several threads on a knitting or knitting machine with organs for adjusting the stitch size and with thread delivery devices for at least some of the threads. The thread delivery devices are designed for measuring and regulating the thread tension, the speed of the threads being adjusted by a device for specifying the thread speed to regulate the thread tension.

The device for thread speed specification uses the control of a selected thread delivery device (a master), which results from this thread delivery device, to control all remaining thread delivery devices.

The object is to develop a method for controlling the delivery of threads with a predetermined thread tension over a longer operating time for several workstations of a textile machine and a corresponding system, the costs for the thread delivery devices being reduced.

This task is solved as follows:
In a method for controlling the delivery of threads of a system with a plurality of thread delivery devices with a predetermined thread tension to a textile machine, the thread tension of at least one thread of a thread delivery device is regulated to a reference value by a tension unit of this thread delivery device. At least one of the thread delivery devices with a tension unit is operated as a master thread delivery device and at least one further thread delivery device is operated as a slave thread delivery device.

In the method, the thread tension of at least one thread is regulated by a master thread delivery device to a reference value and the thread tension of at least one further thread supplied by a slave thread delivery device is controlled by the master thread delivery device. The thread tension of the thread of the slave thread feed device or devices is controlled with the aid of the tension unit of the master thread feed device or the tension units of the master thread feed device by a default control unit.

In an alternative, the thread tension of the thread of the slave thread feed device (s) is controlled by a default control unit, the default control unit being connected to the tension units of at least two master thread feed devices.

The threads are withdrawn from the thread delivery devices through the work stations of the textile machine, the thread delivery devices each having a storage body and a braking device with an adjusting device. The thread tension of the respective thread of the thread delivery devices is set by controlling the corresponding setting device by means of a brake signal. Specific data is assigned to each of the thread delivery devices, the specific data comprising an assignment of values of a braking force determining the thread tension to values of the brake signal.

The thread tension of the thread of the respective slave thread delivery device is controlled by the control unit determining a preset value for the braking force for the slave thread delivery device from the values or the brake signal of the master thread delivery device or devices and specifying the slave thread delivery device.

The default control unit, which is designed to control the thread tension of the thread of the slave thread feed device or devices, is provided in the tension unit of the master thread feed device.

In an alternative, the default control unit is provided in a separate system control unit or is designed as a separate system control unit. The separate system control unit is connected to the tension unit of the master thread delivery device.

With this method, a large number of yarn delivery devices can be operated as a slave yarn delivery device without a tension control unit and can be used with one or more yarn delivery devices with a yarn tension control unit operated as a master yarn delivery device. Thread delivery devices without a tension control unit are less complex and cheaper to manufacture. In this case, thread delivery devices are to be used, each of which is assigned specific data that includes an assignment of values of the thread tension to values of the brake signal. Such yarn delivery devices are from the DE 10 2013 113 115 B4 known.

In one embodiment, the thread tension of the respective thread of the thread delivery devices is set by at least one brake body of the braking device, at least one adjusting element of the adjusting device acting on the braking body or brakes, and the adjusting element (s) being controlled by the brake signal.

In one embodiment, the thread tension of the respective thread of the thread delivery devices is set by adjusting elements of the adjusting device designed as magnetic elements, one magnetic element being movable in the magnetic field of another magnetic element and acting on the brake body, whereby a working current forming the brake signal of one of the two magnetic elements is designed as a working coil Magnetic element is set.

In one embodiment, the thread delivery devices of the system are divided into one or more groups. Master-slave operation is set in at least one of the groups by operating the thread delivery devices as master and slave thread delivery devices. The default control unit for each group with master-slave operation separately determines the default value for the braking force for the slave thread delivery device (s) in the group and the slave thread delivery device (s) in the group.

In one embodiment, an initialization is carried out before the specification of the specification value.

During initialization, the specific control data for at least the thread delivery devices with tension unit are queried by the default control unit for each group in the master-slave operation, and the slave thread delivery devices are set to a default state.

In the specification, the specification control unit determines the specification value for the braking force from the value or values of the brake signal of the master thread supply device (s) with the help of the specific data of the master thread supply device (s) and the slave thread supply device (s). If necessary, the specification is repeated.

In an alternative, the specification is repeated continuously. The repetition takes place in an example with a frequency in the range of 10 Hz, i. H. approximately every 100 ms.

In one embodiment, the preset value for the braking force is determined by the preset control unit from a filtered value of the values of the brake signal of the master yarn feed device or devices or from filtered values of the brake signals of the master yarn feed devices.

In one example, a filtered value is an average value of the values of the brake signals of the respective master thread delivery device. In an alternative, the filtered value is a moving average of the values of the brake signal.

In the case of several master thread delivery devices, the default control unit in turn determines an average value from the filtered values.

In one embodiment, infinite impulse response filters (IIR filters) or alternatively finite impulse response filters (FIR filters) are used to determine an average value.

In one embodiment, the default value for the braking force is determined by the default control unit from an average value of values of the brake signals from at least two master thread delivery devices.

The features and advantages of the device claims correspond to those of the method claims.

A textile machine is provided with a system for controlling the delivery of threads with several thread delivery devices with a predetermined thread tension to work stations of the textile machine. The system comprises at least two yarn delivery devices, for example at least one yarn delivery device with tension unit and at least one yarn delivery device without yarn tension unit.

In the thread delivery device with tension unit, the tension unit is designed to regulate the thread tension of the thread of the thread delivery device to a reference value. At least one thread delivery device with a tension unit can be operated as a master thread delivery device and at least one further thread delivery device can be operated as a slave thread delivery device, the thread tension of the thread of the slave thread or delivery devices using the tension unit of the master thread delivery device or the tension units of the master thread delivery devices a default control unit is controlled.

The thread delivery devices each have a storage body and a braking device in the course of the thread downstream of the storage body, the threads of the thread delivery devices being pulled off the storage body by the work stations of the textile machine. The braking device has an adjusting device for adjusting the thread tension, the adjusting device being controlled by a brake signal.

Specific data is assigned to the thread delivery devices of the system, the specific data comprising an assignment of values of a braking force determining the thread tension to values of the brake signal.

The default control unit is designed to control the yarn tension of the respective slave yarn delivery device by determining the default value for the braking force for the slave yarn delivery device from the value or values of the brake signal of the master yarn delivery device or devices and to predefine the slave yarn delivery device (s) is.

In one embodiment, the braking device of the thread delivery devices has at least one braking body in the thread course after the storage body and an adjusting device for adjusting the thread tension, at least one adjusting element of the adjusting device acting on the braking body or brakes, and the adjusting element (s) being controlled by the brake signal.

In one embodiment, the adjusting device of the braking device comprises two actuating elements designed as magnetic elements, one magnetic element being movable in the magnetic field of the other magnetic element and being able to act on the brake body.

To set the thread tension, an operating current forming the brake signal of one of the two magnetic elements designed as a work coil can be set.

In one embodiment, the thread delivery devices of the system are divided into one or more groups. Master-slave operation can be set in at least one group by operating the thread delivery devices as master and slave thread delivery devices. The specification control unit is designed to separately determine the specification value for the braking force for the slave thread supply device (s) in the group and to specify it for the slave thread supply device (s) in the group for each group with master-slave operation.

• Fig. 1 eine schematische Darstellung eines Fadenliefergerätes ohne Fadenspannungseinheit anhand einer Seitenansicht;
• Fig. 2 eine schematische Darstellung eines Fadenliefergerätes mit einer Fadenspannungseinheit anhand einer Seitenansicht;
• Fig. 3 ein vereinfachtes Blockschaltbild einer Textilmaschine mit einem System mit mehreren Fadenliefergeräten eines ersten Beispiels;
• Fig. 4 ein Ausschnitt des Blockschaltbilds der Fig. 3 mit Pfeilen zur Darstellung der Kommunikation einer Vorgabe;
• Fig. 5 ein vereinfachtes Ablaufdiagramm einer Initialisierung;
• Fig. 6 ein vereinfachtes Ablaufdiagramm einer Vorgabe eines Vorgabewertes;
• Fig. 7 ein vereinfachtes Blockschaltbild eines Systems mit mehreren Fadenliefergeräten eines zweiten Beispiels, wobei die Fadenliefergeräte in Gruppen unterteilt sind; und
• Fig. 8 ein Blockschaltbild der ersten beiden Gruppen der Fig. 7 mit Pfeilen zur Darstellung der Kommunikation einer Vorgabe.

The invention is further explained using two examples shown schematically in the drawing. Show it:

• Fig. 1 a schematic representation of a thread delivery device without thread tension unit based on a side view;
• Fig. 2 a schematic representation of a thread delivery device with a thread tension unit based on a side view;
• Fig. 3 a simplified block diagram of a textile machine with a system with several yarn delivery devices of a first example;
• Fig. 4 a section of the block diagram of the Fig. 3 with arrows to show the communication of a specification;
• Fig. 5 a simplified flow chart of an initialization;
• Fig. 6 a simplified flow diagram of a specification of a default value;
• Fig. 7 a simplified block diagram of a system with several yarn delivery devices of a second example, wherein the yarn delivery devices are divided into groups; and
• Fig. 8 a block diagram of the first two groups of Fig. 7 with arrows to show the communication of a specification.

A textile machine T with a system for controlling the delivery of threads with a predetermined thread tension to work stations of a textile machine comprises a plurality of thread delivery devices VC, ATC. The system comprises thread delivery devices VC without a tension unit and thread delivery devices ATC each with a tension unit for regulating the thread tension of the thread 40 of the thread delivery device ATC. At least one thread delivery device ATC can be operated as a master thread delivery device and at least one further thread delivery device VC can be operated as a slave thread delivery device.

First example:

In a first example, the system has a group of 16 thread delivery devices. A thread delivery device ATC with a tension unit can be operated as a master thread delivery device and 15 thread delivery devices VC without a tension unit can be operated as slave thread delivery devices. Figure 1 shows a schematic representation of a yarn feeder VC without tension unit and Figure 2 a corresponding representation of a thread delivery device ATC with a tension unit. A simplified block diagram of the textile machine T with the system with the 16 thread delivery devices ATC, VC is shown in Figure 3 shown.

Figure 1 shows one of the yarn delivery devices VC, which is designed as a storage yarn delivery device. The thread delivery device VC has a holder 2, a winding unit, a storage body 3, of which the thread 40 passes through a work station A1, A2, A3, ... A16 (cf. Figure 3 ) the textile machine T is withdrawn, and a braking device for setting a thread tension. The braking device comprises an adjusting device, the adjusting device for adjusting the thread tension being controlled by a brake signal. The textile machine T is, for example, a circular knitting machine.

The holder 2 is provided with a fastening device 4 for fastening the thread delivery device VC to the textile machine T, for example to a machine ring of the circular knitting machine.

The storage body 3 is designed as a storage drum with an axis 5. At the winding end, in the Figure 1 At the upper end, the storage body 3, the winding unit for winding yarn turns, ie turns of the thread, is arranged on the storage body 3. The winding unit is provided with a drive arranged in a drive housing 6 and a winding element 7 which can be driven by the drive.

The holder 2 extends parallel to the axis 5 along the storage body 3. The drive housing 6 is at the winding end, in Figure 1 attached to the holder 2 at the upper end of the storage body 3.

The braking device for setting a thread tension of the thread 40 has a braking body 8 and the setting device for the braking body 8. The brake body 8 is arranged after the storage body 3 in the course of the thread, it being arranged at the withdrawal end of the storage body 3 shown in dashed lines. A housing 9 of the braking device is fastened to the holder 2 at an end of the storage body opposite the drive housing 6.

The brake body 8 is conical, specifically as a flexible brake body cone in the form of a regular truncated cone. For example, it is made of a plastic and / or metal. Corresponding or similar brake bodies are for example in the WO 2006/045410 A1 described.

The axis of the brake body 8 is essentially correct, i. H. except for slight deviations B. by lifting by the thread 40 or upon deformation of the elastic brake body 8, with the axis 5 of the storage body 3. The withdrawal end of the storage body 3 is rounded and forms an annular clamping surface 10 in the region of the rounding. The larger diameter of the braking body 8 projects beyond the clamping surface 10. It can be pressed against the clamping surface 10 at the withdrawal end of the storage body 3 by the adjusting device.

When the thread 40 is withdrawn by the textile machine T, the thread 40 runs from the storage body 3 through the gap between the withdrawal end of the storage body 3 and the brake body 8 via the clamping surface 10.

The adjusting device has control elements, namely magnetic elements, one magnetic element being movable in the magnetic field of another magnetic element and acting on the brake body 8. One of the magnetic elements is designed as a work coil. In this example, the setting device comprises a permanent element, hereinafter referred to as the PM element, and the work coil movable in the magnetic field of the PM element. The PM element and the work coil are in the housing 9 and are in Figure 1 not visible. The work coil acts on the brake body 8. The work coil works on the principle of a plunger coil, which is referred to as "voice coil" in English.

The magnetic elements of the adjusting device can be controlled by a brake signal, namely by an operating current for the work coil. Upon contact with the brake body 8, loading the work spool with a certain working current leads to a slight axial movement of the work spool, which may be slight, and thus to a change in the contact pressure of the brake body 8 against the clamping surface 10. A desired thread tension is set by changing the contact force .

To completely relieve the brake body 8, the working current is changed such that the work coil is moved back into a position in which it no longer acts on the brake body 8 with a contact pressure.

Starting from the housing 9, the holder 2 forms an electronics chamber E, in which electronic elements of the setting device, such as a power supply unit, are arranged for controlling the work coil. In Figure 1 the area of the electronics chamber E above the housing 9 can be seen.

Such a braking device is in the DE 10 2013 113 115 A1 and the DE 10 2013 113 122 A1 described.

Figure 2 shows the yarn delivery device ATC with a tension unit, which corresponds to a yarn delivery device VC without tension unit, except for the features described below.

The thread delivery device ATC additionally comprises a tension unit for regulating the thread tension with a tension measuring unit which has a thread tension sensor 50, a measuring device 51 and a connection 52. Figure 2 schematically shows the thread tension sensor 50 with the measuring device 51 indicated by arrows, which in the thread course behind the housing 9, ie in Figure 2 on the lower side. The measuring device 51 of the thread tension sensor 50 is connected to the thread delivery device 1 via the connection 52. The thread tension sensor 50 is attached to the housing 9.

The in Figure 1 and 2nd Thread delivery devices VC, ATC shown are each assigned specific data spD. The specific data spD include an assignment of values of a braking force determining the thread tension to values of the brake signal, ie to values I of the working current.

The thread delivery devices VC, ATC each have a processor unit with a data unit for outputting the data spD specific to the respective thread delivery device VC, ATC. The data unit is designed to provide the specific data spD. The specific data spD include an assignment of values of the brake signal, namely values I of the working current to measured values F of the braking force determining the thread tension. I.e. the data unit contains values I of the working current for the respective thread delivery device VC, ATC, which are assigned specific values F of the braking force.

To determine the specific data spD, the values I of the working current are assigned measured values F of the braking force.

For example, to determine the specific data spD on the basis of braking force-current curves, the value F of the braking force caused is measured as a function of the value I of the working current in the work coil.

In one example, to determine the specific data spD of a yarn delivery device VC, ATC by the z. B. increasing values I of the working current measured values F of the braking force laid a straight line. The specific data spD, in this example the parameters P1, P2 of the straight line, which assigns the values F of the braking force to the values I of the working current: $$\mathrm{F}=\mathrm{<figure-callout\; id="1"\; label="P"\; filenames="imgf0003.png,imgf0005.png"\; state="\{\{state\}\}">P</figure-callout>}1+\mathrm{P}\mathrm{2nd}\times \mathrm{I.}.$$

A determination and use of specific data is in the DE 10 2013 113 115 B4 described.

Figure 3 shows the simplified block diagram of the system of the first example with the ATC thread delivery device with tension unit that can be operated as a master thread delivery device, the 15 thread delivery devices VC that can be operated as slave yarn delivery devices without tension unit, of which only four can be seen, and the separate system control unit NMT, in which one Default control unit is arranged.

In Figure 3 the respective thread 40 of the thread delivery device ATC, VC to a work station 1, 2, 3, ... 16 of the textile machine T is indicated.

The system control unit NMT is connected via a communication link K1 to the thread delivery devices ATC, VC and optionally via a further communication link K2 to a machine control M of the textile machine T. The communication link K1 is designed as a serial communication link. The communication link includes e.g. B. a CAN bus.

Figure 4 shows the principle of a default value using a block diagram. The default control unit arranged in the system control unit NMT sends a question via the communication link K1 about the value I of the working current of the thread delivery device ATC which can be operated as a master thread delivery device and has a voltage unit: "I?". The value I of the working current is sent back by the voltage unit of the master thread delivery device. This is symbolized by the two outer arrows.

The default control unit turns the value I of the working current of the master thread delivery device or several values I into a default value for the braking force, i. H. for the corresponding thread tension, which the thread delivery device VC, which can be operated as a slave thread delivery device, is determined without a tension unit.

In this example, a braking force with the value F is determined from the value I of the working current and the specific data spD of the master thread delivery device, namely the parameters P1 and P2, according to the formula (1) given above. This value F, referred to as the default value, is sent to the slave thread delivery devices by the default control unit via the communication line K1. This is symbolized by the inner arrows.

For each thread delivery device VC that can be operated as a slave thread delivery device without a voltage unit, the processor unit determines the value I _i of the operating current from the value F for the thread tension and the specific data spD _i , namely the parameters P1 _i and P2 _i , of the thread delivery device VC: $${\mathrm{I.}}_{\mathrm{i}}=\left(\mathrm{F}-\mathrm{P}{1}_{\mathrm{i}}\right)/\mathrm{P}{\mathrm{2nd}}_{\mathrm{i}}$$

In operation , the supply of threads of the system is controlled with 16 thread delivery devices VC, ATC with a predetermined thread tension to work stations of the textile machine T. The thread tension of the thread 40 of the thread delivery device ATC is regulated by the tension unit of the thread delivery device ATC to a reference value Mref.

The 16 yarn delivery devices VC, ATC form a group, the yarn delivery device ATC with voltage unit being operated as a master yarn delivery device. The other yarn delivery devices VC without tension unit are operated as slave yarn delivery devices.

A thread control unit controls the thread tension of the thread of the slave thread feed devices with the aid of the tension unit of the master thread feed device.

The thread delivery devices VC, ATC each have a storage body 3 and a braking device in the thread course after the storage body 3.

The threads of the thread delivery devices VC, ATC are each withdrawn from the storage body 3 by the work station A1, A2, A3, ... A16 of the textile machine T. The thread tension of the respective thread of the thread delivery devices VC, ATC is set by an adjusting device of the braking device. The setting device is controlled by a brake signal.

To regulate the thread tension of the thread of the master thread delivery device, the brake signal is set by the tension unit of the master thread delivery device.

Specific data spD is assigned to the thread delivery devices VC, ATC of the system. The specific data spD include an assignment of values of the braking force determining the thread tension to values of the brake signal.

The thread tension of the thread of the respective slave thread delivery device is controlled by the control unit determining a preset value for the braking force for the slave thread delivery device from at least one value of the brake signal of the master thread delivery device. The default value is given to the slave thread delivery device.

The thread tension of the respective thread of the thread delivery devices VC, ATC is set by the brake body 8 of the braking device. At least one control element of the adjusting device acts on the brake body 8. The control elements are controlled by the brake signal.

For this purpose, the thread tension of the respective thread of the thread delivery devices VC, ATC is set by the adjusting elements of the adjusting device, which are designed as magnetic elements. One of the magnetic elements, which is movable in the magnetic field of the other magnetic element, acts on the brake body 8. A working current forming the brake signal of one of the two magnetic elements, designed as a working coil, is set.

In master-slave operation, an initialization is first carried out and then a default value is specified. Figure 5 shows a simplified flow diagram of an initialization and Figure 6 a simplified flow diagram of a specification.

At one in Figure 5 Initialization of the group of thread delivery devices VC, ATC shown in master-slave operation, the specific data spD of the master thread delivery device are queried by the default control unit and the slave yarn delivery devices are set to a default state.

In a first step, the thread control device ATC with tension unit is defined as master thread feed device and the 15 thread feed devices VC without tension unit are defined as slave thread feed devices by the default control unit.

In a second step, the specific data spD of the master thread delivery device are queried and stored by the default control unit. In this example, the specific data spD are the parameters P1 and P2 of the straight line, which assigns the values F of the braking force to the values I of the working current.

In a third step, the slave thread delivery devices are assigned to the master delivery device by the default control unit.

In a fourth step, the slave thread delivery devices are put into a default state by the default control unit, in which they are ready to assign a specific value F _i of the braking force to their specific value I _{i of} the thread tension and to set this value.

At one in Figure 6 The default shown in the group of yarn delivery devices VC, ATC in master-slave operation is the default control unit, the default value for the braking force from the value of the brake signal of the master yarn delivery device, ie from the working current of the master yarn delivery device, using the specific data spD of the master yarn feeder is determined and given to the slave yarn feeder.

As already related to Figure 4 explained, in a first step the default control unit arranged in the system control unit NMT asks for the value I of the working current of the master thread delivery device.

In a second step, a time t is waited, in which the value I of the working current is sent back by the voltage unit of the master thread delivery device.

In a third step, the default control unit checks whether the value I has been sent. If this is not the case, the specification is ended without controlling the slave thread delivery devices.

In a fourth step, the default control unit uses the value I of the working current or a plurality of values to determine a default value for the braking force of the yarn delivery devices VC that can be operated as slave yarn delivery devices without a tension unit.

In this example, a filtered value of the brake signal is formed from the value of the brake signal, ie from the working current I, by the default control unit. For example, a temporal mean value I _{m is} formed from the values I of the working current, from which the default value, ie the value F for the braking force, is determined.

In a fifth step, the default value, i.e. H. the value F, specified by the default control unit to the slave thread delivery devices.

The specification of the specification value for the values of the braking force of the slave thread delivery devices is repeated. The repetition is automatic, e.g. B. after 100 ms, d. H. with a frequency of 10 Hz.

The time average is z. B. formed as a moving average I _m . If an earlier value I (t-1) and the current value I (t) of the working current at time t are used, the following average value I _m results: $${\mathrm{I.}}_{\mathrm{m}}=\left(\mathrm{I.}\left(\mathrm{t}-1\right)+\mathrm{I.}\left(\mathrm{t}\right)\right)/\mathrm{2nd}.$$

This averaging is also referred to as an FIR filter.

Alternatively, the mean value I _m is calculated as follows: $${\mathrm{I.}}_{\mathrm{m}}\left(\mathrm{t}\right)=\left(\mathrm{I.}\left(\mathrm{t}\right)+{\mathrm{I.}}_{\mathrm{m}}\left(\mathrm{t}-1\right)\right)/\mathrm{2nd}$$

This averaging is also referred to as an IIR filter.

Alternatively, 3 or more previous values are included in the calculation of a moving average.

In one example, the determined value I _{m is provided} with a correction value I _k to determine the value I: $$\mathrm{I.}={\mathrm{I.}}_{\mathrm{m}}+{\mathrm{I.}}_{\mathrm{k}}$$

The correction value I _k is greater than zero. In an alternative, the correction value is less than zero.

In an alternative, the determined value I _{m is} multiplied by a correction value I _c . In one alternative, the correction value I _{c is} greater than 1. In another alternative, the correction value I _{c is} less than 1.

The correction values compensate for different designs of the yarn delivery devices VC, ATC.

Second example:

The second example corresponds to the first example except for the features described below.

Figure 7 shows the simplified block diagram of the system with the yarn delivery devices VC, ATC of the second example, which are divided into several groups G1, G2, G3, G4, ... G16. The system has e.g. B. 256 yarn delivery devices VC, ATC, the yarn delivery devices VC, ATC being divided into 16 groups G1, G2, G3, G4, ... G16, each with 16 yarn delivery devices VC, ATC.

In an alternative, the system e.g. B.126 Thread delivery devices VC, ATC.

The first group G1 comprises a yarn delivery device ATC that can be operated as a master yarn delivery device with a tension unit and 15 yarn delivery devices VC that can be operated as a slave yarn delivery device without a tension unit.

The second and third groups G2 and G3 each comprise two thread delivery devices ATC that can be operated as a master thread delivery device with a tension unit and 14 thread delivery devices VC that can be operated as a slave thread delivery device without a tension unit.

The position and address of the thread delivery devices VC, ATC are important for the system assignment on the knitting machine.

In the second group G2, in addition to a thread delivery device ATC, two thread delivery devices VC and a second thread delivery device ATC are arranged in a 1st position. In the third group G3, the thread delivery devices ATC with tension unit are arranged side by side.

The separate system control unit NMT, in which a default control unit is arranged, is connected to the thread delivery devices ATC, VC via the communication link K1. The communication link K1 is designed as a serial link, e.g. B. with at least one CAN open BUS.

Figure 8 shows the principle of a default value using a block diagram.

In group G1 the specification of the default value is carried out as in the first example. The default control unit queries the value I of the working current of the master thread delivery device and uses it to determine the default value, namely the value F (I) of the braking force as a function of the working current I, using the specific data of the master thread delivery device. The value F (I) is specified for the slave thread delivery devices in group G1.

The values I1 and I2 are, for example, mean values calculated according to equation (3) or (3a). From the values I1 and I2, values F1 and F2 are determined in accordance with equation (1) for the braking force. The value F (I1, I2) is, for example, an average of F1 and F2.

In group G2, the default control unit queries the values I1 and I2 of the working current of the two master thread delivery devices. From the values I1 and I2, the default control unit uses the specific data of the master thread delivery devices to determine the default value, namely the value F (I1, I2) of the braking force as a function of working currents I1 and I2. The value F (I1, I2) is specified for the slave thread delivery devices in group G2.

The default value is determined in group G3 as in group G2.

In operation , the thread delivery devices VC, ATC are operated as master and slave thread delivery devices in the first three groups G1, G2, G3.

The default control unit for each of the groups G1, G2, G3 with master-slave operation separately determines the default value for the braking force for the slave thread delivery devices of the respective group G1, G2, G3 and the slave thread delivery device or groups G1, G2, G3 specified.

The thread tension of the threads of the slave thread delivery devices of the first group G1 is controlled by the control unit determining a preset value of the braking force for the slave thread delivery devices from the values of the brake signal of the master thread delivery device and specifying the slave thread delivery devices.

The thread tension of the threads of the slave thread delivery devices of the second and third groups G2, G3 is controlled by the control unit for each of the groups G2, G3 specifying a preset value of the braking force for the slave thread delivery devices of the respective group G2, G3 from the values of the brake signals the two master thread delivery devices of the respective group G1, G2 is determined and the slave thread delivery devices of the respective group G2, G3 are specified.

For each group G1, G2, G3 in master-slave operation, the specific data spD of the master yarn delivery devices are queried during initialization by the default control unit and the slave yarn delivery devices are set to a default state.

In the specification, the specification control unit uses the specification of the braking force of the respective group G1, G2, G3 from the value of the brake signal of the master thread delivery device in group G1 and from the values of the brake signals of the two master thread delivery devices in groups G2 and G3 determined with the help of the specific data spD of the master thread supply device (s) and given to the slave thread supply devices of the respective groups G1, G2, G3; and repeated the default.

In the first group G1, the default value for the braking force is determined by the default control unit from the value of the brake signal of the master thread delivery device.

In groups G2 and G3, the default value for the braking force is determined by the default control unit, for example from an average value of the values of the brake signals of the two master thread delivery devices. As soon as the values of the brake signals have been received from the master thread delivery devices for all groups G1, G2, G3 in master-slave operation, one after the other, and the default values for the slave thread delivery devices of the respective groups G1, G2, G3 have been determined , these are sent to the slave thread delivery devices. This process is repeated continuously.

Reference symbol list

1

Thread delivery device

2nd

holder

3rd

Storage body

4th

Fastening device

5

axis

6

Drive housing

7

Take-up element

8th

Brake body of the brake device

9

casing

10th

Clamping surface

E

Electronics chamber

40

thread

50

Thread tension sensor

51

Measuring device

52

connection

K1

Communication link

K2

Communication link

M

Machine control

NMT

central control device

T

Textile machine

Claims (11)

1. Method for controlling the feed of threads of a system with several thread feeders (VC, ATC) with a pre-determined thread tension to workstations (A1, A2, A3, ... A16) of a textile machine (T),
   wherein the thread tension of at least one thread of a thread feeder (ATC) is regulated to a reference value (Mref) by a tensioning unit of the thread feeder (ATC),
   wherein at least one thread feeder (ATC) with a tensioning unit is operated as a master thread feeder and at least one further thread feeder (VC) as a slave thread feeder,
   wherein the thread tension of the thread of the slave thread feeder(s) is/are controlled via the tensioning unit of the master thread feeder or the slave thread feeders of the master thread feeders with a setpoint controller,
   wherein the threads of the thread feeders (VC, ATC), which each have a storage body (3) and a braking device in the thread path downstream from the storage body (3), are each drawn off from the storage body (3) by the workstation of the textile machine (T), wherein the thread tensioning of the respective thread of the thread feeder (VC, ATC) is adjusted by a adjusting device of the braking device and the adjusting device is controlled with a braking signal,
   wherein the braking signal is adjusted by the respective tensioning unit of the master thread feeder for regulating the thread tension of the thread of the master thread feeder(s),
   wherein, to the thread feeders (VC, ATC) of the system, specific data (spD) are each allocated, wherein the specific data (spD) comprises an allocation of values of a braking force determining the thread tension to values of the braking signal, and
   the thread tension of the thread(s) (40) of the slave thread feeder(s) is controlled in that the setpoint controller calculates a setpoint value for the braking force for the slave thread feeder(s) from the value(s) of the braking signal of the master thread feeder(s) and presets this to the slave thread feeder(s).
2. Method according to claim 1, characterised in that the thread tension of the respective thread of the thread feeders (VC, ATC) is adjusted with the aid of at least one brake body (8) of the braking device, wherein at least one adjustment element of the adjusting device acts on the brake body/bodies (8), and wherein the adjustment element(s) is/are controlled with the braking signal.
3. Method according to claim 2, characterised in that the thread tension of the respective thread of the thread feeders (VC, ATC) is adjusted by adjustment elements of the adjusting device designed as magnet elements, wherein one magnet element is moveable within the magnet field of another magnet element and acts on the brake body (8), wherein a working current forming the braking signal of one of the two magnet elements, designed as a working coil of said magnet element, is adjusted.
4. Method according to one of the claims 1 to 3, characterised in that the thread feeders (VC, ATC) of the system are divided into one or more groups (G, G1, G2, G3, ... G16), wherein a master/slave operation is adjusted in at least one group (G, G1, G2, G3) in that the thread feeders (ATC, VC) are operated as master and slave thread feeders, wherein, separately for each group with a master/slave operation, the setpoint controller calculates the setpoint value for the braking force for the slave thread feeder(s) of the group (G, G1, G2, G3), and this is preset to the slave thread feeder(s) of the group (G, G1, G2, G3).
5. Method according to claim 4, characterised in that the specific data (spD) for each group (G, G1, G2, G3) is queried for at least the thread feeders (ATC) with a tensioning unit during an initialisation with the aid of the setpoint controller during master/slave operation, and the slave thread feeders are then placed in a preset condition;
   the setpoint value for the braking force is calculated from the value(s) of the braking signal of the master thread feeder(s) for a presetting of the setpoint controller with the aid of the specific data (spD) of the master thread feeder(s), and is preset to the slave thread feeder(s); and the presetting is possibly repeated.
6. Method according to one of the claims 1 to 5, characterised in that the setpoint value for the braking force is calculated by the setpoint controller from a filtered value of the values of the braking signal of the master thread feeder, or from filtered values of the values of the braking signals of the master thread feeders.
7. Method according to one of the claims 1 to 6, characterised in that the setpoint value for the braking force is calculated by the setpoint controller from a median value of values of the braking signals of at least two master thread feeders.
8. Textile machine with a system for controlling the feed of threads with several thread feeders (VC, ATC) with a pre-determined thread tension to workstations of the textile machine (T) with at least two thread feeders (VC, ATC), wherein at least one thread feeder (ATC) has a tensioning unit for regulating the thread tension of the thread of the thread feeder (ATC) to a reference value (Mref),
   wherein at least one thread feeder (ATC) with a tensioning unit can be operated as a master thread feeder, and at least one further thread feeder (VC) as a slave thread feeder, and wherein the thread tension of the thread of the slave thread feeder(s) (VC) is controlled via the tensioning unit of the master thread feeder or the tensioning units of the of the master thread feeders with a setpoint controller,
   wherein the thread feeders (VC, ATC) each have a storage body (3) and a braking device in the thread path downstream from the storage body (3), wherein the threads of the thread feeders (VC, ATC) are each drawn from the storage body (3) by the workstations of the textile machine (T), wherein the braking device has a adjusting device for adjusting the thread tension, wherein the adjusting device is controlled with a braking signal,
   wherein the thread feeders (VC, ATC) are each allocated specific data spD,
   wherein the specific data spD comprises an allocation of values of a braking force determining the thread tension to values of the braking signal, and
   the setpoint controller is designed for controlling the thread tension of the respective slave thread feeder in that the setpoint value for the braking force for the slave thread feeder is calculated from the value(s) of the braking signal of the master thread feeder(s) and is preset to the slave thread feeder(s).
9. Textile machine according to claim 8, characterised in that the braking device of the thread feeders (VC, ATC) has at least one brake body (8) in the thread path downstream from the storage body (3) and has a adjusting device for adjusted the thread tension, wherein at least one adjustment element of the adjusting device acts on the brake body/bodies (8), wherein the adjustment element(s) is/are controlled with the braking signal.
10. Textile machine according to claim 9, characterised in that the adjusting device of the braking device comprises two adjustment elements designed as magnet elements, wherein one magnet element is moveable within the magnetic field of the other magnet element and can act on the brake body (8), and wherein a working current of one of the two magnet elements, the magnet element designed as a working coil generating the braking signal, can be adjusted for adjusting the thread tension.
11. Textile machine according to one of the claims 8 to 10, characterised in that the thread feeders (VC, ATC) of the system are divided into one or more groups (G, G1, G2, G3, ... G16), wherein a master/slave operation can be adjusted for at least one group (G, G1, G2, G3) in that the thread feeders (VC, ATC) are operated as master and slave thread feeders, wherein the setpoint controller is designed for separately calculating setpoint value for the braking force for the slave thread feeders of the group (G, G1, G2, G3) for each group (G, G1, G2, G3) with a master/slave operation, and for stipulating this to the slave thread feeder(s) of the group (G, G1, G2, G3).

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