EP3168179B1 - Method of driving a textile machine producing cross-wound bobbins - Google Patents

Description

The invention relates to a method and / or a device for operating a cross-wound textile machine, which has a plurality of individually driven, autonomously operating workstations and a central control unit. The cross-wound textile machine is, for example, a cross-winding machine or an open-end rotor spinning machine.

As is generally known, the jobs of textile machines producing cross-wound bobbins, for example automatic winder or open-end rotor spinning machines, in order to be able to operate properly, constantly require a sufficient supply of energy.

At the workstations of cheese packages, for example, during operation, in addition to electrical energy, suction air is also constantly required in order to suck off the fiber dust which continuously occurs during the rewinding process.
The Saugluftbedarf the jobs of such textile machines is exacerbated when, for example, after a yarn breakage or a controlled cleaner cut the accumulated on the cross-wound yarn end must be picked up by a workstation's own suction and transported to a yarn splicing device. A particularly high intake air requirement, which often overstrains the performance of the machine's own suction air system, is particularly present when, for example, after a batch change a large number of jobs to be re-pooled simultaneously.

When operating the jobs of open-end rotor spinning machines in addition to electrical energy and constantly a pneumatic vacuum is required.
That is, in the rotor housing of the open-end spinning device of the workstations of such textile machines, a so-called spinning vacuum must constantly prevail, which ensures during the spinning operation that the dissected from an opening roller of a master fiber strand single fibers are fed via a Faserleitkanal pneumatically in the spinning rotor, where be rotated from the spinning at high speed spinning rotor to a thread.

In these known and in the textile industry for a long time in use in large numbers in use open-end rotor spinning machines often comes in special events, such as a yarn break at one or more job (s), an automatically operating control unit, a so-called Anspinnwagen to Insert, which successively executes the thread breaks that have occurred at the workstations. This operating unit is also used when at a restart of the textile machine, for example after a batch change or after a power failure, which led to a shutdown of all jobs of the textile machine concerned, all jobs must be re-spun again.
That is, after a batch change or after a power failure, the control unit spins all jobs again in succession, which is relatively tedious and has a very negative effect on the production management of the open-end rotor spinning machines.
In particular, in countries with a sensitive infrastructure, in which energy losses are not rare events, the efficiency of such, supplied by control units textile machines can therefore often be relatively low.

In order to shorten the time required for the workstations of an open-end rotor spinning machine to run properly again after a power failure or a batch change, open-end rotor spinning machines have been developed in the past which have self-sufficient work stations. That is, the jobs of such open-end rotor spinning machines are able to automatically spin after a spin interruption without the help of an operating unit.

This example in the DE 101 39 075 A1 Relatively extensively described, self-sufficient workplaces that have, inter alia, each one connected to the vacuum system of an open-end rotor spinning, working-own suction nozzle, have, at least temporarily, an increased energy demand, which is always present when the job again automatically after a spin interruption re-spun, that is, when the workstation's own vacuum-pressurized suction nozzle is looking for a thread end which has accumulated on the surface of a cheese, has to be picked up and transported to a thread-spinning device, where it is then prepared for piecing.

In order to prevent too many of these independently working jobs from starting again after a batch change or a power failure, which would overstrain the vacuum system of the textile machine and consequently lead to negative piecing attempts, various methods have already been developed in the past in which after a game change or a power failure, the number of each simultaneously starting a piecing attempt jobs is limited.

In the DE 10 2006 050 220 B4 For example, a method for operating an open-end rotor spinning machine is described with which a demand-based allocation of provided by a Saugluftanlage the textile machine suction air to vacuum requesting, self-sufficient working points of the textile machine should be guaranteed.
The textile machine has to cover the Saugluftbedarf their self-sufficient jobs, which, as indicated above, can be quite different, via a machine-own Saugluftanlage having a vacuum source whose drive motor is connected to a frequency converter and defined in terms of its speed adjustable ,
A central control unit of the textile machine also ensures that the negative pressure in the suction system does not fall below a certain minimum level.

In order to avoid that the Saugluftbedarf the textile machine is above the maximum Saugluftangebot the respective Saugluftanlage, although the speed of the drive motor of the vacuum source was increased to a maximum speed is provided according to this known method that in the central control unit of the textile machine incoming vacuum requirements of jobs after at least a first priority class and a second priority class are distinguished, with negative pressure requirements, which are classified in the first priority class, are always processed preferably preferred.

Furthermore, in the DE 10 2007 006 679 A1 a method for operating a cheese-producing textile machine described, which also has a plurality of individually driven, autonomously operating jobs, a central control unit and a suction system with at least one suction unit.

Again, the suction of the Saugluftanlage can be increased by the speed of the drive motor of the Saugluftaggregates to reach a maximum speed, wherein the speed of the drive motor is controlled by monitoring the vacuum level in the Saugluftanlage.

In this known method is from the known maximum speed of the drive motor of Saugluftaggregates, which defines the maximum suction of Saugluftanlage the textile machine, as well as from the present actual speed of the drive motor of the Saugluftaggregates, resulting from the instantaneous vacuum demand of the textile machine, a value for a Speed reserve calculated by means of which the number of jobs that can be supplied with additional negative pressure is determined.

From this number, increased by the number of currently with additional vacuum on the basis of the actual speed of the drive motor already supplied jobs then a maximum number of jobs is determined, which can be supplied with additional negative pressure simultaneously. This maximum number of circuits exceeding negative pressure requirements are rejected.

In such a mass start not only problems arise with the vacuum supply, but also the supply of electrical energy and / or compressed air, with the communication between a central control and the workstations by means of bus systems and the emergence of mechanical vibrations, for example, when lowering the packages to their respective Contact rollers.

The DE 43 38 283 A1 and the JP H09 21021 A reveal textile machines in which the jobs are started gradually.

Based on methods of the type described above, the invention has for its object to develop a method and a cheese-producing textile machine for performing the method, which can be ensured that it is at a mass start of all jobs or a mass start a variety of jobs of an open Rotor spinning machine, which may be required, for example after a batch change or after a power failure, does not come to the occurrence of disturbances due to bottlenecks or overloads.

This object is achieved in that the jobs affected by a mass start of all jobs of the textile machine or at a start of a variety of jobs of the textile machine jobs are started successively by the switch-on for the following jobs on the first job each by a minimum period of 1 ms is delayed compared to the previously started job. According to the invention, the presence of all necessary conditions for the start of the jobs is monitored and in their absence, the turn-on are each additionally additionally delayed with respect to the minimum time until these conditions for the next successful start again.

Advantageous embodiments of the method according to the invention are the subject of the subclaims.

The inventive method avoids that in a first start phase of the jobs, the communication links are overloaded by simultaneously differentiated communication between the central control unit and each of the jobs done. While a simple broadcast command that is distributed equally to all workstations does not yet result in congestion, it is problematic to send corresponding responses from the workstations to the central control unit over the data bus at the same time. Furthermore, by the successive lowering of the stored in their creel lifted off cheeses on long machines their placement equalized on their drive rollers and avoided a possibly not insignificant oscillation. Finally, a sudden rash in the energy supply is suppressed. In subsequent subsequent phases of the recommissioning of the work stations, that is, the thread search and the subsequent start of the spinning and / or winding process takes place in a known manner, the systematic staggering of the processes, in particular depending on the Saugluftbedarf. These phases then extend over a significantly longer period of several seconds than the claimed minimum periods of time.

The inventively provided minimum period of 1 ms already leads to the aforementioned equalization of otherwise concurrent operations.

The advantageous extension of the minimum period of time, for example to 5 ms or 15 ms in claims 2 and 3 leads to a further, significantly greater equalization of said processes, with a minimum period of 15 ms has been found in experiments to be particularly advantageous.
In an advantageous embodiment, it is also provided according to claim 4 that depending on the job number for each job an individual delay time is calculated. This means that the minimum time span is multiplied by the job number, which ultimately leads to a kind of turn-on shaft along the textile machine. However, within the scope of the invention, an almost arbitrary deviating sequence of the switch-on pulses, for example one after the other odd-numbered and then even-numbered jobs can be selected.

In this way, the timing of the startup of a job can be reliably specified.

According to claim 5, the monitored conditions include the power supply, the pressure and Saugluftbereitstellung and / or communication technology, the Saugluftbereitstellung already belongs to the phases following the first phase, which is not already available for a high number of jobs anyway, but in groups at the same time can be demanded.

The cheese-producing textile machine according to the invention for carrying out the method according to the invention has a multiplicity of individually drivable, autonomously operating work stations with workstation-specific control devices and via a central control unit.
The central control unit has a switching device on which a mass start of all jobs of the textile machine or a mass start a variety of jobs of the textile machine can be initiated and the switching device or the workstation's own control devices are designed so that the affected jobs are started successively by the turn-on for the on the first job following jobs is delayed in each case by a minimum period of 1 ms compared to the previously started job. According to the invention, it is proposed to monitor the existence of all necessary conditions for the start of the jobs and that, in the absence thereof, the switch-on pulses are additionally delayed with respect to the minimum time span until these conditions are present again for the next successful start.

The inventively provided minimum period of 1 ms already leads to the equalization of otherwise simultaneously occurring processes. This already begins with the fact that the lowering and setting down of the cheeses, which takes place in a first step, does not lead to a considerable oscillation of the machine due to simultaneity. The successive communication by means of the machine bus avoids overloading the communication links. Energy and compressed air requirements are also equalized.

The advantageous extension of the minimum period of time, for example to 5 ms or 15 ms in claims 7 and 8 leads to a significantly greater equalization of said processes, with a minimum period of 15 ms has been found in experiments to be particularly advantageous.

The generation of the power-up sequence can be done according to claim 9 and 10 either centrally in the central control unit or decentralized in the workplaces. The delay of the start signal at the respective workstations is advantageously calculated from the product of an individual size of the workstation and the minimum time span. If the generation of the power-up sequence takes place only in the workstations, a broadcast signal is first sent to all workstations by the switching device of the central control unit. As a result, the determination of the individual delay of the start time is initiated in the workstations and then the transmission of the response signals is staggered via the data bus.

In an advantageous embodiment, it is also provided according to claim 11 that an individual delay time is calculated depending on the job number for each job. This means that the minimum time span is multiplied by the job number, which ultimately leads to a kind of turn-on shaft along the textile machine. However, within the scope of the invention, an almost arbitrary deviating sequence of the switch-on pulses, for example one after the other odd-numbered and then even-numbered jobs can be selected.

In this way, the time of the startup of a job can be reliably specified, with the result that it is ensured that at the same time always only a certain number of jobs is in the startup phase.

According to claim 12, the monitored conditions include the power supply, the pressure and Saugluftbereitstellung and / or communication technology, the Saugluftbereitstellung already belongs to the phases following the first phase, which is not available simultaneously for a large number of jobs, but in groups at the same time can be demanded.

The invention will be explained in more detail with reference to an embodiment schematically illustrated in the drawings.

• Fig.1 eine Vorderansicht einer Kreuzspulen herstellenden Textilmaschine mit autark arbeitenden Arbeitsstellen, an der das erfindungsgemäße Verfahren zum Einsatz kommt,
• Fig.2 eine einzeln antreibbare, autonom arbeitende Arbeitsstelle einer Kreuzspulen herstellenden Textilmaschine, im Ausführungsbeispiel einer Offenend-Rotorspinnmaschine.

It shows:

• Fig.1 a front view of a cross-wound textile machine producing self-sufficient workstations on which the inventive method is used,
• Fig.2 a separately driven, autonomously operating workstation of a cheese-producing textile machine, in the embodiment of an open-end rotor spinning machine.

In Fig. 1 is schematically in front view of a cheese-producing textile machine, in the embodiment, an open-end rotor spinning machine 5, shown.

Such textile machines have between their end frames 31, 32 a plurality of identical, hereinafter with reference to Fig.2 described in more detail, self-sufficient work stations 1 and have a central control unit 10 and a machine-own suction system 20th

As can be seen, a vacuum source 30 of the Saugluftanlage 20 is disposed in one of the end frames of the open-end rotor spinning machine 5, wherein the vacuum source 30 by an electro-motor drive 29 which is defined by means of a frequency converter with respect to its speed adjustable, is applied.
The drive 29 or the associated frequency converter is connected via a control line 35 to a central control unit 10 of the textile machine 5, which has a switching device 12, via which the operator can input control commands into the central control unit 10.

How out Fig. 1 Furthermore, the central control unit 10 is also connected via a bus system, preferably via a CAN bus 28, to the workstation's own control devices 25 of the numerous independently operating work stations 1.
In the present embodiment, the textile machine 5 is also equipped with a movable along the workstations 1 operating unit 7, preferably a so-called cleaning and changer car equipped.

Among other things, this cleaning and changer cart 7 ensures that finished cheeses are transferred from the creel 22 of the workstations 1 to a (not shown) Spulenabtransportband the textile machine 5 and new empty tubes in the creel 22 of the jobs 1 are changed.

The Fig. 2 shows in perspective one of the many largely self-sufficient working places 1 in Fig.1 schematically illustrated open-end rotor spinning machine. 5

Such a workstation 1 has, as is known per se and therefore only shown schematically, always an open-end rotor spinning device 2 as well as a winding device 3.

In the embodiment, in the region of the open-end rotor spinning device 2, in front of a so-called thread withdrawal tube 21, also a piecing 16 is arranged, which accumulated after a yarn break or a controlled cleaner cut on the cheese 8, by a pivotally mounted, underdruckbeaufschlagbare suction nozzle 4 of the cheese 8 retrieved thread 9 and prepares the thread end for rebirth.

Furthermore, such a workstation 1 has a thread withdrawal device 27, which takes over both the removal of the thread 9 from the open-end spinning device 2 during the regular spinning operation, as well as the re-spinning for a defined return of a prepared thread 9 in the open-end spinning device 2 provides ,

The winding device 3 has, as usual, a creel 22 for rotatably supporting a cross-wound bobbin 8, a preferably powered by a reversible single drive 36 drive drum 23 and a Fadenchangiereinrichtung 24 which is driven by means of a stepping motor 37, for example.
In addition, a thread centering device in the form of a pivotably mounted centering plate 11 can be arranged in front of the thread-changing device 24.

In the exemplary embodiment, the workstation 1 is also equipped with a thread monitor 26, a paraffining device 17 and a pneumatically actuable storage nozzle 40, which stores excess thread length during run-up of the job 1 and thereby ensures that the yarn produced in the open-end spinning device with a proper Winding tension is wound up.

Both the storage nozzle 40 and the pivotally mounted suction nozzle 4 are connected via a defined controllable device 13 to the machine's own suction system 20 of the open-end rotor spinning machine 5. That is, the suction nozzle 4 and the storage nozzle 40 can be acted upon when required with negative pressure.
The pivotally mounted suction nozzle 4 is also adjustable by means of a stepping motor 6 between a thread receiving position lying in the region of the winding device 3 and a yarn transfer position lying in the region of the spinning device 2.

Function of the method according to the invention, explained with reference to FIG.

If, for example, after a batch change or a power failure, the open-end rotor spinning machine 5 has to be restarted, an authorized operator at the switching device 12 of the central control unit 10 enters a corresponding command for a mass start of the work stations 1.
The central control unit 10 then sends via the bus system 28 corresponding start pulses to the workstation's own control devices 25, the numerous start pulses are each delayed by a minimum period of 1 ms, preferably 15 ms, sent to the individual jobs 1.
The delay time compared to the first start signal is dependent, for example, on the job number. That is, when the central control unit 10 is commanded to re-start the open-end rotor spinning machine by an operator, the work stations 1, initiated by a switching means 12 of the central control unit 10, spin in turn, offset by a delay time of 15 ms from their predecessor , new. The switch-on pulses run in the case of using the workstation number for the delay sequence like a wave through the open-end rotor spinning machine.

As an alternative to the central generation of the sequence of the switch-on pulses, a broadcast command could also be issued by the central control unit 25 or the switching device 12, which initiates the determination of the individual switch-on delay in the workstations.

In the open-end rotor spinning machine all conditions for the complete start of the jobs 1 are monitored. This is after a first phase, in which the communication via the CAN bus 28 and the compressed air and power supply takes place, mainly to the Saugluftbereitstellung.

If at a point in time during the sequential transmission of switch-on pulses, all are no longer present for the start of the workstations, in particular with regard to the conditions required for the first phase, the Switch-on pulses delayed from the set minimum time period until the conditions for the next start are present again.
A prior determination of the minimum period of time, for example, to 1, 5 or 15 ms, results from known conditions that would directly lead to interference in an overlap of the turn-on, such as in the communication or energy or compressed air supply.

The further phases of the piecing process such as the thread search and the actual piecing are largely independent of the first phase and include, as already known, a delay which is essentially dependent on the sufficient suction air supply. For example, a maximum of 12 or 24 spinning stations can be adequately supplied with suction air at the same time, so that staggering of the initiation of the piecing phases following the first phase can also take place in groups and with a greater time interval than in the claimed minimum period of time.

Although the invention has been explained with reference to an open-end rotor spinning machine, the same problems can occur in a cheese winder, which can be solved in the same way by realizing the features of the present invention.

Claims (12)

1. Method for operating a textile machine (5) that produces a cross-wound packages and comprises a plurality of workstations (1), which can be actuated individually and operate autonomously, and a central control unit (10), the workstations (1) affected by a mass activation of all workstations (1) of the textile machine (5) or by an activation of a plurality of workstations (1) of the textile machine (5) being activated in succession,
   characterised in that,
   the switch-on pulse for each workstation downstream of the first workstation is delayed by a minimum time period of 1 ms by comparison with the workstation activated previously, and in that monitoring is carried out as to whether all the necessary conditions for activating the workstations are met, and in that if they are not met, the switch-on pulses are delayed further by comparison with the minimum time period until the conditions for the next successful activation are met.
2. Method according to claim 1, characterised in that, the minimum time period is 5 ms.
3. Method according to claim 2, characterised in that, the minimum time period is 15 ms.
4. Method according to one of claims 1 to 3, characterised in that, the switch-on pulse sequence is based on the workstation numbers.
5. Method according to one of the preceding claims, characterised in that, the monitored conditions include the power supply, the supply of compressed air and suction air and/or the communications technology.
6. Textile machine (5) producing cross-wound packages, comprising a plurality of workstations (1), which can be actuated individually, operate autonomously and each comprise their own control device (25), and a central control unit (10) for carrying out the method according to claim 1, the central control unit (10) having a switching device (12), by which a mass activation of all the workstations (1) of the textile machine (5) or an activation of a plurality of workstations (1) of the textile machine (5) can be initiated, and the switching device (12) or the individual control devices (25) of each workstation being configured such as to activate the affected workstations (1) in succession,
   characterised in that,
   the switch-on pulse for each workstation downstream of the first workstation is delayed by a minimum time period of 1 ms by comparison with the workstation activated previously, and in that the central control unit (10) or the individual control devices (25) of each workstation monitor whether the necessary conditions for activating the workstations are met, and the switch-on pulses are delayed further by comparison with the minimum time period until the conditions for the next successful activation are met.
7. Textile machine producing cross-wound packages according to claim 6, characterised in that, the minimum time period is 5 ms.
8. Textile machine producing cross-wound packages according to claim 7, characterised in that, the minimum time period is 15 ms.
9. Textile machine producing cross-wound packages according to one of claims 6 to 8, characterised in that, the switching device (12) is configured to generate a sequence of switch-on pulses shifted by the minimum time period and to send said sequence to the workstations (1), each switch-on pulse being provided with the address of the relevant workstation (1), and the delay associated with each workstation corresponding to the product of a specific variable of the workstation (1) and the minimum time period.
10. Textile machine producing cross-wound packages according to one of claims 6 to 8, characterised in that, the switching device (12) is configured to send a broadcast activation command that initiates the activation at all workstations (1) to be activated, the individual control devices of each workstation being configured, after having received the broadcast activation command, to delay the activation by a time period that corresponds to the product of a specific variable and the minimum time period.
11. Textile machine producing cross-wound packages according to either claim 9 or claim 10, characterised in that, the sequence of the switch-on pulses is based on the workstation numbers.
12. Textile machine producing cross-wound packages according to claim 6, characterised in that, the monitored conditions include the power supply, the supply of suction air and/or the communications technology.

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