The present invention refers to a method and an apparatus for the optimisation of a plurality of adjustment parameters for adjusting a joining device for joining textile threads or yarns for textile machines, in particular automatic winding machines. The present invention also concerns an automatic winding machine comprising the aforementioned optimisation apparatus.

It is known that textile machines and, in particular, automatic winders or winding machines are equipped with numerous work stations, each of which is equipped with a joining device for joining the textile thread or yarn being processed, suitable for restoring continuity in the case of its interruption caused by accidental breaking or by a deliberate elimination of defective segments or even by the running out of a spool from which the thread or yarn is unwound.

Such joining devices, known in the jargon as splicer, carry out the knotless pneumatic joining of the ends of textile thread or yarn. Indeed, they use a compressed gas, typically compressed air, possibly with added water and/or heated, both as means for untwisting the ends of the thread or yarn to be joined, and as joining means to interlace the fibres of such ends.

In detail, a known joining device typically comprises a pneumatic preparation device in which the textile threads or yarns to be joined are subject to at least one flow of a fluid at a predetermined pressure for a predetermined time interval, and a joining chamber in which the textile threads or yarns to be joined are superimposed for a superimposition section of predetermined length and are subsequently joined through at least one further flow of a fluid at a predetermined pressure for a predetermined time interval.

Different models of joining devices are currently known that differ from one another by the type of joining that they are configured to make.

For example, there are joining devices that make the joining inside the respective joining chambers through the action of one or more flows of compressed air, or through the combined action of one or more flows of compressed air with added water, or through the action of one or more flows of heated compressed air.

Each of these models of joining devices is particularly suitable for carrying out the joining of textile threads or yarns as a function of the type or of the count or of the twisting.

In any case, each joining device can be configured by setting a plurality of adjustment parameters indicative, for example, of the pressure or of the temporal duration of such flows, or of the length of the superimposition section between the two ends of the threads or yarns to be joined.

Currently, the choice and the relative configuration of the joining device to be applied to a winding machine is carried out, as a function of the thread or yarn being processed, by an operator that performs manual verifications of the resistance to breaking and an observation of the aspect of the joining itself.

The configuration of the joining device used can therefore be modified by the operator until the joining is considered acceptable by the operator himself both in terms of resistance to breaking and of aspect.

A configuration process of the joining device like the one described above suffers from a few drawbacks.

A first drawback consists of the fact that the configuration made by the single operator is not deterministic, but varies according to the operator's judgement, which in turn depends on his experience and talent .

In this case, it is indeed possible for two different operators to configure the same joining device differently, obtaining different results.

A second drawback consists of the fact that, in order to ensure that a high quality joint is made in short time periods, it is necessary to use highly qualified operators, involving high workforce costs.

Added to this is the fact that the manual configuration of the joining devices in any case involves slowing down of the production process.

A further drawback, finally, consists of the fact that the aspect of the joining is judged by the eye of the expert operator and, therefore, it is not always possible to ensure a high quality joining is obtained since the operator can make judgement errors.

The purpose of the present invention is to avoid the aforementioned drawbacks and, in particular, to devise a method and an apparatus for the optimisation of a plurality of adjustment parameters for adjusting a joining device for joining textile threads or yarns for textile machines, in particular automatic winding machines capable of configuring such a joining device in a deterministic and automatic manner.

Another purpose of the present invention is to devise a method and an apparatus for the optimisation of a plurality of adjustment parameters for adjusting a joining device for joining textile threads or yarns for textile machines, in particular automatic winding machines capable of verifying the quality of the aspect of the join more accurately than the prior art.

These and other purposes according to the present invention are accomplished by making a method and an apparatus for the optimisation of a plurality of adjustment parameters for adjusting a joining device for joining textile threads or yarns for textile machines, in particular automatic winding machines as outlined in the independent claims.

Further features of the method and of the apparatus for the optimisation of a plurality of adjustment parameters for adjusting a joining device for joining textile threads or yarns for textile machines, in particular automatic winding machines are the object of the dependent claims.

The features and advantages of a method and an apparatus for the optimisation of a plurality of adjustment parameters for adjusting a joining device for joining textile threads or yarns for textile machines, in particular automatic winding machines according to the present invention, will become clearer from the following description, given as an example and not for limiting purposes, referring to the attached schematic drawings, in which:

- figure 1 is a block diagram showing an embodiment of an apparatus according to the present invention;

- figure 2 is a flow chart showing a first embodiment of a method for the optimisation of a plurality of adjustment parameters for adjusting a joining device for joining textile threads or yarns for textile machines, in particular automatic winding machines according to the present invention;

- figure 3 is a flow chart showing a second embodiment of a method for the optimisation of a plurality of adjustment parameters for adjusting a joining device for joining textile threads or yarns for textile machines, in particular automatic winding machines according to the present invention;

- figure 4 is a flow chart showing an embodiment of a second verification test of the joining comprised in the method of figure 3;

- figure 5 is a schematic view of an automatic winding machine according to the present invention;

- figure 6 is a schematic lateral view of a winding head of the winding machine of figure 5.

With reference to figure 1, an apparatus is shown wholly indicated with 20.

Such an apparatus 20 is advantageously used for the optimisation of a plurality of adjustment parameters for adjusting a joining device 10 for joining textile threads or yarns .

The joining device 10 comprises at least one pneumatic preparation device 11, in which the ends of the parent textile threads or yarns to be joined are subject to at least one flow of a fluid at a predetermined pressure for a predetermined time interval, and a joining chamber 12 in which the ends of the parent textile threads or yarns to be joined are inserted side by side and superimposed to each other for a superimposition section of predetermined length and are subsequently joined through at least one further flow of a fluid at a predetermined pressure for a predetermined time interval .

For example, the fluid used in the pneumatic preparation device is compressed air; the fluid used in the joining chamber can be for example compressed air or a mixture of air and water.

The plurality of adjustment parameters comprises one or more of the following parameters:

- pressure of the at least one flow of a fluid in the pneumatic preparation device 11;

- pressure of the at least one further flow of a fluid in the joining chamber 12;

- time interval of the duration of the at least one flow of a fluid in the pneumatic preparation device 11;

- time interval of the duration of the at least one further flow of a fluid in the joining chamber 12;

- length of the superimposition section.

The apparatus 20, according to the present invention, comprises a test station 21 provided with connections and electrical power, pneumatic and possibly hydraulic supply 27 for the aforementioned joining device 10 and with insertion and extraction means 28 for the insertion (mechanical arms) into the joining device of the ends of the parent textile threads or yarns to be joined and for the extraction of the joined textile thread or yarn from the joining device.

The apparatus 20 also comprises an apparatus, per se known, for the mechanical resistance tests 22 provided for performing a first verification test of the mechanical resistance of the joined thread or yarn and a vision electronic system 23 provided for performing a second verification test of the joined thread or yarn. Advantageously, the apparatus also comprises a processing and controlling unit 24 configured for controlling the joining device 10 for joining textile threads or yarns with which the apparatus 20 is associated, the apparatus for the mechanical resistance tests 22 and the vision electronic system 23 so as to implement the optimisation method 100 according to the present invention.

Preferably, the apparatus 20 can also be provided with a database 25 in which the relative joining device 10 and the corresponding plurality of optimised adjustment parameters are stored in association with each type of textile thread or yarn.

In particular, after each optimisation, the processing and controlling unit 24 of the apparatus 20 provides for saving the optimised parameters in the database 25 so as to obtain an archive of historical data on the various types of joint examined.

Preferably, the vision electronic system 23 comprises visual acquisition means 26, one or more photo cameras or telecameras, provided for acquiring at least one image of at least one portion of the thread or yarn to be joined or joined.

Once the adjustment parameters for adjusting a joining device 10 have been optimised through the apparatus 20, it is then possible to configure the joining devices of a group of automatic winding machines (not illustrated) which operate on the same type of textile thread or yarn treated previously by the apparatus 20. The optimised adjustment parameters can also be transmitted to the winding machines through a telecommunications network, for example a local LAN network or the Internet. In this case, both the winding machines and the optimisation apparatus are connected to such a telecommunications network.

Moreover, the optimisation apparatus can be advantageously integrated in an automatic winding machine 50 like the one illustrated in figure 5.

Such an automatic winding machine 50 comprises at least two winding heads 51, preferably in a number that can vary between eight and seventy.

Each winding head 51 in turn comprises a spool 52 from which the thread is unwound, a reel 53 on which the thread is wound during the normal operation of the winding machine 50. In an intermediate position with respect to the path of the thread between the spool 52 and the reel 53, each winding head 51 comprises a joining device 10, a device for monitoring the thread 56 and two movement arms for moving the textile thread or yarn 54 and 55. Such arms 54 and 55 are, in particular, provided for inserting the two ends of the textile thread or yarn to be joined into the joining device 10.

According to the present invention, one of the at least two winding heads 51' is provided with the optimisation apparatus 20 described above. In this case, the insertion and extraction means 28 of the test station of the apparatus 20 comprise the movement arms 54 and 55 of the winding head 51'; moreover, the connections and the air and/or water suppliers of the test station coincide with those of the winding head 51' .

In this way, it is possible to obtain the optimal configuration of the joining device 10 on the winding head 51', which is provided with the optimisation apparatus, and to apply such an optimised configuration to all of the remaining winding heads 51 of the winding machine 50. The optimisation operation can, in particular, be carried out at the end of a processing cycle of the winding machine 50 or by blocking such a machine for the time interval necessary to carry out the optimisation procedure or between two successive processing operations or before the end of a processing operation while the other heads continue the current processing. In any case, the integration of the apparatus 20 in the automatic winding machine 50 allows obtaining the optimal configuration of the joining devices directly in production without the need for laboratory tests.

The optimisation method 100 for optimising the plurality of adjustment parameters for adjusting a joining device according to the present invention will be described hereafter. The joining device 10 to be configured comprises a joining chamber 12 and a pneumatic preparation device 11 already previously selected by an operator after an examination of each end of the textile thread or yarn to be joined aimed at evaluating the type of fibre and/or the number of twists and/or the count of the textile thread or yarn. The optimisation method 100 comprises an initial step in which, on the basis of the textile characteristics of the parent textile thread or yarn to be joined, one proceeds to the configuration of a joining device 10 assigning a corresponding plurality of predetermined initial values to the plurality of adjustment parameters for adjusting the device 10. The aforementioned textile characteristics comprise the type of fibre (cotton, wool, polyester, viscose) of the textile thread or yarn to be joined and/or the number of twists and/or the count of such a yarn.

Following the configuration step of the joining device 10, the joining of the ends of the threads or yarns is carried out 102 through the configured joining device 10.

At this point, at least one first verification test of the joined thread or yarn, belonging to a predetermined plurality of verification tests, is carried out 103. The plurality of verification tests can comprise size tests or measurements of mechanical characteristics and so on.

Such a first verification test comprises, preferably, the step in which the quality of the mechanical resistance characteristics of the joined textile thread or yarn is verified through the apparatus for the mechanical resistance tests 21.

In detail, if the first verification test has a negative result, one proceeds modifying 104 at least one adjustment parameter of the plurality of parameters and perform the joining and the subsequent first verification test again.

The first verification test can have a negative result, for example, if the joined thread or yarn has a resistance to breaking lower than at least 80% of the resistance of the parent textile thread or yarn.

Otherwise, if the first verification test has a positive result, the joining is marked 105 as acceptable and the corresponding adjustment parameters as optimised. In this case, therefore, the examination of the joining is based on the result of a single verification test.

Alternatively, if the first verification test has a positive result, at least one second test for verifying the joined thread or yarn, belonging to the predetermined plurality of verification tests, is carried out 110.

In particular, this second test comprises the step in which the quality of the diameter of the joined textile thread or yarn is verified through the vision electronic system 23. In such a case, the second test is aimed at verifying that the diameter of the joining differs from the diameter of the parent thread or yarn within certain tolerance limits.

If the second verification test has a negative result, at least one adjustment parameter is modified 104 again and the previous steps of making the joining and the first verification test of the same are carried out again.

When the second verification test also has a positive result, the joining is marked 105 as acceptable and the adjustment parameters as optimised. In this case, it is possible to store such optimised parameters in association with the type of textile thread or yarn treated in the database 25.

Advantageously, the steps of modifying 104 at least one adjustment parameter that are carried out in the case of a negative result of the first and/or second verification test comprise the step in which the adjustment parameters are modified one at a time according to a predetermined order on the basis of the type of textile thread or yarn to be joined. Such a predetermined order is set by an operator through user interface means (not illustrated) , generally a keyboard and a monitor.

Preferably, the optimisation method 100 provides for the step in which an invitation signal inviting to replace the selected joining chamber 12 and/or the pneumatic preparation device 11 is emitted, if for the same textile thread or yarn to be joined the making of the joining and of the subsequent first verification test of resistance to breaking are repeated for a first maximum number of times and each time the first verification test has a negative result.

Preferably, the optimisation method 100 provides for the step in which an invitation signal inviting to replace the selected joining chamber 12 and/or the pneumatic preparation device 11 is emitted, if for the same textile thread or yarn to be joined the making of the joining and of the subsequent first and second verification tests are repeated for a second maximum number of times and every time the second verification test has a negative result.

The first and the second maximum numbers are set by an operator through the user interface means.

In the presence of the aforementioned invitation signal the operator can then proceed performing the aforementioned replacements. In a preferred embodiment of the present invention, the second verification test 110 of the joined textile thread or yarn comprises the step in which at least one first image of at least one portion of the parent textile thread or yarn to be joined is acquired 111 through the visual acquisition means 26 of the vision electronic system 23.

Thereafter a plurality of describing parameters for describing the aspect of such a parent thread or yarn to be joined is calculated 112 through processing of the at least one first acquired image, wherein such a plurality of describing parameters comprises the average value and the standard deviation of the diameter, the number of excess and in fault outliers of the thread or yarn.

By number of excess outliers we mean the number of sections of the joining having a diameter greater than the average value of the diameter of the parent textile thread or yarn by an amount greater than the tolerance limits proportional to the standard deviation.

By number of in fault outliers we mean the number of sections of the joining having a diameter less than the average value of the diameter of the parent textile thread or yarn by an amount greater than the tolerance limits proportional to the standard deviation.

At this point at least one second image of at least one portion of the joined thread or yarn is acquired 113 through the aforementioned visual acquisition means, where such a portion comprises the joining.

Then a plurality of describing parameters for describing the aspect of the joining is calculated 114 through a processing of the at least one second acquired image, where such a plurality of describing parameters comprises the average value and the standard deviation of the diameter.

In this way it is also possible to calculate 115, 116 a first number nl and a second number n2 of portions of the joined thread or yarn having a diameter respectively substantially greater or less than the average value of the diameter of the parent textile thread or yarn to be joined.

Thereafter, therefore, the first number nl and the second number n2 are compared 117 with the numbers of excess and in fault outliers, respectively, calculated previously; in detail, during this comparison step the joining is marked as acceptable if the first number nl and the second number n2 are lower than the numbers of excess and in fault outliers, respectively, calculated previously .

The steps of processing images, of calculating parameters and of comparison are performed by the processing and controlling unit 24 through software means (not illustrated) .

In the case in which the joining is not considered acceptable, the second verification test provides for the step in which the joining is marked as having in fault material if the second number n2 is greater than the calculated number of in fault outliers.

On the contrary, the joining is marked as having excess material if the second number n2 is lower than the calculated number of in fault outliers and if the first number nl is greater than the calculated number of excess outliers.

From the description that has been made the characteristics of the method and of the apparatus for optimisation object of the present invention are clear, just as the relative advantages are also clear.

The optimisation apparatus allows to quickly obtain the ideal adjustment for the joining device so as to make an acceptable joining both in terms of structure and of aspect .

Indeed, the vision electronic system of the aforementioned apparatus allows to perform the second verification test of the aspect of the joined textile thread or yarn completely automatically without the help of an operator. Therefore, a deterministic and replicable adjustment of the joining device is obtained, at the same time reducing the workforce cost for the expert operators necessary to evaluate the quality of the joints.

Moreover, the method and the apparatus according to the present invention allow to create an archive of historical data, thanks to which it is possible to adjust the joining devices even more quickly.

Once the adjustment of a joining device has been performed, it is then possible to apply the corresponding adjustment parameters to all of the joining devices associated with the automatic winding machines that operate on a textile thread or yarn having the same characteristics as that used in the apparatus. In this way, the time taken to make a plurality of reels is reduced. The production process is further streamlined if the optimisation apparatus is integrated in one of the winding heads of an automatic winding machine .

Finally, it is clear that the method and the apparatus thus conceived can undergo numerous modifications and variants, all of which are covered by the invention; moreover, all of the details can be replaced by technically equivalent elements. In practice, the materials used, as well as the sizes, can be whatever according to the technical requirements.