TECHNICAL FIELD

The present invention relates to the technical field of thread consuming devices. In particular, the present invention relates to a system comprising a treatment unit to be used in association with such thread consuming device.

BACKGROUND

It has been suggested to provide thread consuming devices, such as embroidery machines or the like, with in-line apparatuses designed to provide the thread with a certain treatment. Such in-line apparatuses could e.g. be used to colour the thread, whereby multiple colour nozzles could replace the current use of multiple pre-coloured threads when producing multi-coloured patterns using embroidery machines. In prior art systems where threads of different colours are used, one thread, having a first specified colour, is used for some stitches while another thread, having a second specified colour, is used for other stitches.

In order to eliminate the obvious drawbacks of the requirement of multiple threads of different colours, the present applicant has filed several patent applications on the technique of in-line colouring of thread, such as WO2016204687 and

WO2016204686. The proposed solutions provide improvements in terms of colour quality and also reduces the complexity of the thread consuming device.

However, in order to further improve the quality of the in-line colouring of threads it would be advantageous if the in-line colouring apparatus would be modified to increase the accuracy of the dispensing of the coating substance.

SUMMARY

An object of the present invention is therefore to provide a solution

overcoming the disadvantages of prior art. More specifically, the present invention provides a solution where the system for in-line treatment of a thread is configured to control the dispensing from the discharge devices based on an evaluated thread consumption of a thread consuming device. In a first aspect, a system for in-line treatment of thread for use with a thread consuming device is provided. The system comprises a treatment unit comprising at least one discharge device being configured to dispense one or more coating substances onto the at least one thread when activated. The system further comprises a control unit configured to evaluate the thread consumption of a thread consuming device based on operation data and at least one parameter being related to one or more thread

consumption parameter. The control unit is further configured to control the dispensing from the discharge device based on said evaluated thread consumption.

Since the thread consumption is evaluated, the thread to be treated with one or more coating substances will be treated with the intended coating substance.

In a second aspect, a system for in-line treatment of thread for use with a thread consuming device is provided. The system comprises a treatment unit comprising at least one discharge device being configured to dispense one or more coating substances onto the at least one thread when activated. The system further comprises a control unit configured to evaluate the thread consumption of a thread consuming device based on operation data and at least one parameter being related to one or more thread

consumption parameter. The control unit is further configured to alter the thread consumption of the thread consuming device based on said evaluated thread

consumption.

In the control unit of the first or second aspect, the control unit may further be configured to evaluate the thread consumption and/or updating the operation data and/or at least one thread consumption parameter based on a simulation of the thread consumption.

The simulation of the thread consumption may be performed continuously during the operation of the thread consuming device and/or during the operation of the treatment unit.

In one embodiment, the simulations at least are based on stored consumption data comprising information from previous runs of the thread consuming device.

The control unit may further be configured to evaluate the thread consumption based on stored consumption data comprising information from previous runs of the thread consuming device, and/or update the operation data and/or at least one thread consumption parameter based on stored consumption data comprising information from previous runs of the thread consuming device.

The operation data of the thread consuming device may comprise information of positional coordinates of a driving pattern of the thread consuming device. The thread consuming device is configured to make stitches into a substrate, and wherein the operation data further comprises a number that is related to the current stitch number of the thread consuming device.

The thread consuming device may be configured to make stitches into a substrate, and wherein the thread consumption parameter is related to one or more substrate parameters and/or to one or more stitches parameters of the thread consuming device.

The one or more substrate parameters may be related to one or more of the thickness of the substrate, the elasticity of the substrate, the placement of the substrate in the thread consuming device, or any combination thereof.

The one or more stitches parameters may be related to one or more of the tension of the at least one thread, the angle to which the at least one thread is applied to the substrate, the angle of at least the last stitch, features related to underlying stitches, or in any combination thereof.

The substrate may be a fabric. The nozzles may be inkjet nozzles. The coating substance may be a colouring substance.

The systems of the first and second aspect may further comprise at least one thread consuming device. The thread consuming device may be an embroidery machine, a sewing machine, a knitting machine, a weaving machine, a tufting machine, a thread winding machine, and or any combination thereof.

In a third aspect, a method for in-line treatment of at least one thread for use with a thread consuming device is provided. The method comprises the steps of providing a treatment unit comprising at least one discharge device being configured to dispense one or more coating substances onto the at least one thread when activated and providing a control unit. The method further comprises evaluating the thread

consumption of the thread consuming device based on operation data and at least one parameter being related to one or more thread consumption parameter, and controlling the dispensing of one or more coating substances based on said evaluated thread consumption.

In a fourth aspect, a method for in-line treatment of at least one thread for use with a thread consuming device is provided. The method comprises the steps of providing a treatment unit comprising at least one discharge device being configured to dispense one or more coating substances onto the at least one thread when activated and providing a control unit. The method further comprises evaluating the thread

consumption of the thread consuming device based on operation data and at least one parameter being related to one or more thread consumption parameter, and altering the thread consumption of the thread consuming device based on said evaluated thread consumption.

The method according to the third or fourth aspect, may further comprise the step of evaluating the thread consumption and/or updating the operation data and/or at least one thread consumption parameter based on a simulation of the thread

consumption.

The method may further comprise the step of evaluating the thread

consumption based on stored consumption data comprising information from previous runs of the thread consuming device, and/or updating the operation data and/or at least one thread consumption parameter based on stored consumption data comprising information from previous runs of the thread consuming device.

Definitions

Thread consuming device is in this context any apparatus which in use consumes thread. It may e.g. be an embroidery machine, weaving machine, sewing machine, knitting machine, weaving machine, a tufting machine, a thread winding machine or any other thread consuming apparatus which may benefit from a surface treatment or coating or any other process involving subjecting the thread to a substance, such as dying.

Treatment is in this context any process designed to cause a change of the properties of a thread. Such processes include, but are not limited to, colouring, wetting, lubrication, cleaning, fixing, heating, curing, dying, etc. Thread is in this context a flexible elongate member or substrate, being thin in width and height direction, and having a longitudinal extension being significantly greater than the longitudinal extension of any parts of the system described herein, as well as than its width and height dimensions. Typically, a thread may consist of a plurality of plies being bundled or twisted together. The term thread thus includes a yam, wire, strand, filament, etc. made of various materials such as glass fibre, wool, cotton, synthetic materials such as polymers, metals, polyester, viscos, or e.g. a mixture of wool, cotton, polymer, or metal or any combination thereof

Within this specification, all references to upstream and/or downstream should be interpreted as relative positions during normal operation of the thread consuming device, i.e. when the device is operating to treat an elongated substrate, such as a thread, continuously moving through the device in a normal operating direction. Hence, an upstream component is arranged such that a specific part of the thread passes it before it passes a downstream component.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will be described in the following description of the present invention; reference being made to the appended drawings which illustrate non-limiting examples of how the inventive concept can be reduced into practice.

Fig. la is a schematic view of a system for in-line treatment of thread according to an embodiment;

Fig. lb is a perspective view of a system having a thread consuming device and a treatment unit according to an embodiment;

Fig. 2 is a schematic view of a treatment unit for use with a system according to an embodiment;

Fig. 3 is a schematic view of a discharge device forming part of a treatment unit;

Fig. 4a is a schematic top view of a part of a discharge device according to an embodiment;

Fig. 4b is a schematic top view of a part of a discharge device according to an embodiment; Fig. 5 is a schematic view of a substrate to be used with the system according to Fig. la.

Fig. 6 is a schematic view of parts of a treatment unit according to an embodiment;

Fig. 7 is a schematic view of a method according to an embodiment;

Fig. 8a is a schematic view of a system according to an embodiment, and

Fig. 8b is a schematic view of a system according to an embodiment.

DETAILED DESCRIPTION

An idea of the present invention is to provide a system and method for distributing a coating substance onto a thread in a controlled manner, for use in association with a thread consumption device. Starting in Fig. la a schematic view of system 10 for in-line treatment of thread is shown. The system 10 comprises a treatment unit 100 for dispensing one or more coating substances onto at least one thread. The system 10 further comprises at least one thread consuming device 15, which may e.g. be in the form of one or several embroidery machine(s), a weaving machine(s), a sewing machine(s), knitting machine(s), a tufting machine(s), a thread winding machine(s) etc. The system thereby forms a thread consuming unit, including the at least one thread consuming device 15 and the treatment unit 100. It should be noted that more than one thread can be used in the thread consuming device(s).

It should be noted that several aspects of a system are described within this specification, and they do not require the inclusion of the thread consuming device 15. As will be further understood from the following, for all embodiments the system for in line treatment of thread requires a treatment unit 100, to be used with a thread consuming device 15.

Now turning to Fig. lb the thread consuming device 15 is exemplified as an embroidery machine, here illustrated as a single-head embroidery machine, being equipped with a treatment unit 100. The embroidery machine 15 comprises a moveable stage 2b carrying the fabric to be embroidered. During operation the moveable stage 2b is controlled to rapidly change its position in the X and Y direction (i.e. in this case the horizontal plane, but it could also be in e.g. the vertical plane). The treatment unit 100 allows the embroidery machine 15 to operate without the provision of uniquely pre-coloured threads, as is required for conventional embroidery machines. Instead, the treatment unit 100 provides in-line colouring of a thread 20 in accordance with predetermined colouring patterns, such that a coloured embroidery can be produced. The treatment unit thus replaces individual thread reels as is present in prior art systems.

As is shown in Fig. lb the only connection between the treatment unit 100 and the embroidery machine 15 is the thread 20, as well as electrical connections (not shown). The treatment unit 100 is thus provided as a stand-alone unit having no mechanical connection with the moveable stage 2b.

In an optional embodiment, the stand-alone treatment unit 100 is mounted to the thread consuming device 15 via a suspension arrangement for reducing the transmission of vibrations to the treatment unit 100. During operation, the heavy vibrations of the embroidery machine 15 caused especially by the movement of the stage 2b will not be transmitted to the treatment unit 100 as this is provided as a stand- alone unit. Accurate colouring of the thread during operation is therefore possible.

The various components of the treatment unit 100 are shown in Fig. 2. As can be seen in Fig. 2 a majority of the components are arranged inside a housing 105.

Immediately downstream the thread reel 120 a thread feeder 130 may be arranged, which is configured to pull the thread forward through the treatment unit 100. The thread feeder 130 is not described further herein, but for a more general understanding the thread feeder 130 receives and forwards the thread 20. For this, the thread feeder 130 is controlled by a control unit 190 described further below. The thread feeder 130 is preferably also configured to control the thread tension, e.g. by means of a driven roller, an encoder wheel, and one or more thread guides. After passing the thread feeder 130 the thread 20 engages with a thread guiding device 140. The thread guiding device 140, which may e.g. be in the form of one or more guiding rollers 142, 144 or other suitable means, is ensuring that the thread 20 is aligned with one or more treatment nozzles forming part of at least one discharge device 150.

The discharge device 150 is configured to discharge treatment substance, such as a colouring substance, onto the thread 20 as it passes the discharge device 150. For this the nozzles are arranged preferably in the longitudinal direction of the thread 20 as will be further explained in relation to Figs. 3 and 4.

The discharge device 150 may be moveable by means of a drive unit (not shown). Having a drive unit will make it possible to arrange the discharge device 150 in different operating states in order to perform different tasks, such as for example a first state of dispensing a coating substance to a thread and a second state of performing a cleaning session, or other maintenance or idling. For this a drive unit may be connected to the discharge device 150. The drive unit may be configured to move the discharge device 150 between an idle position and an operational position by means of a transmission having different transmission ratios during the motion from the idle position towards the operational position.

Downstream the discharge device 150 another thread guiding device 160 is provided. The second thread guiding device 160 is cooperating with the first thread guiding device 140 such that the position of the thread 20 is correct during its travel along the discharge device 150. The second thread guiding device 160 may e.g. be in the form of one or more guiding rollers 162, 164, although it may also be designed to induce a rotation of the thread 20 along its longitudinal axis. This extra functionality can provide advantages to the colouring as also will be described below.

The system 10 may further comprise a thread speed sensor (not shown) configured to measure the speed of the thread 20 passing through the system 10.

Moreover, a light detection system (not shown) may be arranged downstream the discharge device 150 along the travel direction of the at least one thread 20. The light detection system is arranged to illuminate the thread 20 in order to receive light which is reflected from the thread 20 when the thread 20 is illuminated. The information gathered from the light detection signal may for example be used to determine the position of the thread in relation to the nozzles l52a-f, the width of the thread and/or properties of the thread. This information can in turn for example be used to detect nozzle(s) that are in need of maintenance, that the position of the nozzle(s) needs to be altered and/or detect variations in the coating substance. Additionally or alternatively, the light detection system may be used to determine different properties of the thread that has been applied with one or several coating substances. The thread 20 is then fed forward to pass one or more fixation units 170 which are provided in order to fixate the treatment substance to the thread 20. The fixation unit 170 preferably comprises heating means, such as a hot air supply or heated elements, or an UV light source such that the treatment substance, e.g. a colouring substance, is cured or fixated onto the thread 20. As is shown in Fig. 2 the fixation unit 170 may either be arranged horizontally, vertically, or at an angle between horizontally and vertically.

Before exiting the housing 105 the thread 20 can pass a cleaning unit 180, such as an ultrasonic bath, where unwanted particles are removed from the thread 20. As the treatment substance is fixated onto the thread 20, the cleaning unit 180 will leave the treatment substance unaffected.

The treatment unit 100 may further comprise a lubrication unit 185 arranged inside the housing 105. Additional thread buffers and feeders (not shown) may also be included in the treatment unit 100, arranged at various positions in the thread path.

The thread 20 preferably exits the treatment unit 100 through an aperture or similar, whereby the thread 20 is forwarded to an associated thread consuming device, such as an embroidery machine 15 as is shown in Figs. la-b.

The thread feeder 130 and the other components engaging with the thread 20 during operation are preferably configured such that the force required to pull the thread 20 from the treatment unit 100, i.e. the pulling force applied by the downstream embroidery machine 15, is approximately the same as if the treatment unit 100 was replaced by prior art thread reels.

A control unit 190 with associated electronics, such as power electronics, communication modules, memories, etc. is also provided. The control unit 190 is connected to the thread feeder 130, the discharge device 150, and the fixation unit 170 for allowing control of the operation of these components. Further, the control unit 190 is configured to controlling operation of the entire treatment unit 100 including the cleaning unit 180, the lubrication unit 185, a disruption of the thread 20, the thread speed at various position along the treatment unit 100, the thread buffers, etc. The control unit 190 may also be configured to receive control signals from one or more components of the treatment unit 100, e.g. control signals for triggering specific control, or other information relating to e.g. thread consumption by the embroidery machine 15. The control unit 190 may be implemented by any commercially available CPU ("Central Processing Unit"), DSP ("digital signal processor") or any other electronic programmable logic device, or a combination of such processors or other electronic programmable logic device. The control unit 190 may be implemented using instructions that enable hardware functionality, for example, by using executable computer program instructions in a general-purpose or special-purpose processor that may be stored on a computer readable storage medium 192 (disk, memory etc) to be executed by such a processor. The storage medium 192 is preferably in operative communication with the control unit 190.

In one embodiment, a user interface is also provided, preferably via a display

195 arranged at the front end of the housing 105. The display 195 allows a user to interact with the control unit 190 and is thus connected thereto, so that the control parameters of the thread feeder 130, the discharge device 150, the fixation unit 170, etc. may be set depending on process specifications. The display 195 may also preferably be used for alerting the user of critical situations, whereby the display 195 may be used for the control unit 190 to issue alarms or the like.

It should be noted that the components described above may not necessarily be included in the stand-alone treatment unit 100, but instead the components of the treatment unit 100 may be separated into several units, of which at least one unit is a stand-alone unit. Preferably, the stand-alone unit includes at least the at least one discharge device 150.

In Fig. 3 a discharge device 150 is shown, forming part of the treatment unit 100 as described above. The direction of movement of the thread 20 in use is indicated by the solid arrow in Fig 3. As will soon be described in more detail, the discharge device 150 comprises a plurality of nozzles l52a-f arranged at different longitudinal positions (for example spaced by a distance dl) along the thread 20 which passes by the treatment unit 100 during use.

Each nozzle l52a-f is arranged to dispense a coating substance, such as ink, onto the thread 20 when the nozzle is activated. The coating substance is absorbed by the thread 20, e.g. at different circumferential positions of the thread 20 when the thread 20 twists about its longitudinal axis. The relative position of two adjacently dispensed droplets of coating substance may be selected such that the droplets will overlap. The treatment unit 100 comprises one or more discharge devices 150. Each discharge device 150 is preferably formed as a series of ink-jet print heads l5la-d, each print head l5la-d having one or more nozzle arrays. Each nozzle array typically comprises hundreds or thousands of nozzles. For illustrative purpose only six nozzles l52a-f are shown for one print head l5la-d; it should however be realized that each nozzle array may be provided with hundreds or thousands of nozzles 152 each. As an example, each print head l5la-d may be associated with a single colour; in the shown example, the discharge device 150 has four print heads l5la-d, each print head l5la-d being associated with a specific colour according to the CMYK standard. However, other colouring models may be used as well.

The exact configuration of the treatment unit 100 may vary. For example, the treatment unit 100 is provided with a single discharge device 150 having a plurality of print heads l5la-d. Each print head l5la-d is in turn provided with a plurality of nozzles l52a-f.

In another embodiment the treatment unit 100 is provided with several discharge devices 150, arranged either in series or in parallel. Each discharge device 150 is then provided with a plurality of print heads l5la-d. If serially arranged, the upstream discharge device 150 may have print heads l5la-d being associated with one or more colours of a specific colour standard, while the downstream discharge device 150 has print heads 15 la— d being associated with other colours of the same colour standard. If arranged in parallel, each discharge device 150 may have print heads l5la-d being associated with all colours of a specific colour standard, but with different threads 20. For such embodiment, two separate threads 20 can be treated simultaneously and in parallel. Combinations of parallel/serial configurations are of course also possible.

In a yet further embodiment, the discharge device 150 is only having a single print head l5la-d; dynamic colouring of the thread 20 would then require several discharge devices 150 of the treatment unit 100.

Each nozzle l52a-f may dispense a coating substance having a colour according to the CMYK colour model, where the primary colours are Cyan, Magenta, Yellow, and Black. It may thus be possible to dispense a wide variety of colours onto the thread by activating nozzles l52a-f such that the total colouring substance of a specific length of the thread 20 will be a mix of the colouring substances dispensed by the nozzles l52a-f. As explained earlier, this is preferably achieved by having several print heads l5la-d arranged in series, whereby the nozzles l52a-f of a specific print head l5la-d are dedicated to a single colour.

In another embodiment, each nozzle l52a-f dispenses a coating substance having a colour comprising a mix of two or more primary colours of the CMYK colour model.

The control unit 190 is configured to control the activation of the nozzles l52a- f such as the coating substance is emitted onto the thread 20 as it passes through the treatment unit 100, and especially pass the discharge device 150. By such configuration very precise colouring of the thread 20 is possible e.g. in order to provide advanced embroidery patterns, visually extremely sophisticated by means of the colouring provided by the treatment unit 100.

For a colouring operation the control unit 190 receives one or more input signals specifying the desired colour and/or colouring effect. The colour input preferably includes information regarding the exact colour, as well as the longitudinal start and stop positions of the thread 20 for that particular colour. The longitudinal start and stop position could be represented by specific time values if the thread speed is determined.

Fig. 4a-b illustrates a respective top view of a print head 15 la. The print head 15 la has a planar surface on which the nozzles 152 are arranged. As mentioned earlier, the total number of nozzles 152 of a single print head can be up to several thousands, provided on a print head 15 la in the size of a couple of centimeters. In the shown example, a far less number of nozzles 152 are shown. The nozzles 152 can be distributed in one or more nozzle arrays 153. In Fig. 4a, the nozzles 152 are distributed in two parallel arrays 153. The arrays 153 are aligned with each other, such that nozzles 152 of one array 153 are arranged adjacent a nozzle 152 of the other array 153.

Fig 4b shows a similar example, however there is a longitudinal offset between the two arrays 153.

As previously described, the thread consuming device 15 is arranged to make stitches 24 into a substrate 30. This is schematically shown in Fig. 5, where the thread is applied to the substrate 30 by stitches 24. In this context, a stitch may for example be a single turn of thread, a single loop of thread, a single turn of yam or a single loop of yam. Stitches may for example be applied using sewing, knitting, embroidery, crochet and/or needle lace-making.

In embroidery, a stitch can for example be seen as a running stitch that pass through the fabric in a simple up and down motion, a back stitch that pass through the fabric in an encircling motion, a chain stitch that catch a loop of the thread on the surface of the fabric, a knotted stitch that is formed by wrapping the thread around the needle. A stitch may be formed by generating two insertion points into the substrate 30.

In knitting, a stitch can be seen as single loop of yarn, secured to the loops beside it to form a row or course of stitches and to the loops above and below it to form a wale. In securing the previous stitch in a wale, the next stitch can pass through the previous loop either from below or above. In crochet, a stitch can be seen as being made by pulling a loop of thread through the previous stitches. Although specific types of stitches have been mentioned, it should be noted that all kinds of stitches can be used for the system disclosed herein.

A plurality of stitches 24 forms an object 26 or a design onto the substrate 30.

The object 26 may be a pattern, figure, shape, text, emblem, symbol, colour gradient or the like. The object 26 may be a logotype or a company name, for example in the form of an embroidery. The operator of the system 10 chooses an object or design to be applied to the substrate, and thus chooses a predetermined stitch pattern. The stitch pattern selected can also be referred to as the driving pattern of the thread consuming device 15.

The substrate 30 is preferably a textile, fabric or cloth. In one embodiment, the substrate 30 has a fixed set of properties, for example a specific thickness and elasticity constant. In the embodiment shown in Fig. 5, the substrate is divided into different sections 30a, 30b. Each section 30a, 30b may have different properties relating to for example the thickness and/or elasticity of the substrate 30.

The inventors of the present invention have after insightful reasoning realized that there are several factors that determine the thread consumption of a thread consuming device 15. The factors may relate to evaluated thread consumption parameters, operation data, simulation data, and/or data received from previous runs. Moreover, it is beneficial if the evaluation of the thread consumption is updated continually to be able to take into account dynamical changes. The combination of several factors provides a more reliable calculation of the thread consumption.

A more reliable calculation of the thread consumption is extra important for an in-line treatment system since the thread is dispensed with one or more coating substances during operation. More specifically, it is beneficial to determine the thread consumption for those stitches that are to be generated between the position where the thread is dispensed with a coating substance and the position where the thread is attached to the substrate by forming a stitch.

The control unit 190 is thus configured to evaluate the thread consumption and based on the evaluated thread consumption control the dispensing from the discharge device 150. The thread consumption may be evaluated in several ways, as is illustrated in Fig. 6.

The control unit 190 is configured to evaluate the thread consumption of a thread consuming device 15 based on operation data 50, simulation data 60, stored data 70, and/or based on thread consumption parameters 40. The estimated thread consumption may be based on one of the above or of a combination of two or more.

The thread consumption may be estimated using operation data 50. The operation data comprises information relating to positional coordinates for each stitch and/or positional coordinates for the driving pattern of the thread consuming device 15. The positional coordinates are based on the selected stitch pattern and describes where the stitches 24 are to be applied to the substrate 30. The positional coordinates may be stored as XY-coordinates. The XY-coordinates may be stored in the form of a vector or matrix. The positional coordinates can be used to determine the thread consumption by calculating the hypotenuse between two insertion points that is used to generate the stitch. In this way, it is possible to get a rough estimate of the thread consumption for that stitch.

The operation data may additionally or alternatively comprise information relating to the length of the stitches. Moreover, the operation data may comprise data relating to the current stitch number.

Simulation data 60 is generated from a simulated operation of the thread consuming device 15. The simulation may be based on different factors, such as operation data 50, thread consumption parameters 40, stored data 70, information of the substrate and/or information of the stitch pattern. The simulation may be performed by the control unit 190 and/or by an external processing unit. The simulation of the thread consumption may be performed continuously during the operation of the thread consuming device 15 and/or during the operation of the treatment unit 100. This allows the system 10 to take into account dynamical changes of the thread consumption once the system 10 is running.

The simulation data 60 may be used to determine an evaluation of the thread consumption and/or to improve other factors such as thread consumption parameters and/or operation data 50. Simulation data is especially beneficial when determining the first stitches of an new run of the thread consuming device 15, since it increases the possibility that the right coating (such as colour) is applied to the right section of the thread in order to receive the right first stitch.

Stored data 70 from previous operational runs of the system 10 may be used to determine an evaluated thread consumption. The data stored from previous runs preferably comprises information relating to consumption data. This information 70 may be used to evaluate the thread consumption in the next run, and/or to improve other factors such as improving the accuracy of the thread consumption parameters 40 and/or improving the accuracy of the simulation data 60.

The control unit 190 is configured to evaluate the thread consumption by processing different kinds of data being related to the operation of the thread consuming device 15 and/or the operation of the discharge device 150. The control unit 190 may be configured to control the operation of the discharge device 150 as a whole, or control one or more of print head(s) l5la-d and/or one or more nozzles l52a-f.

In one embodiment the control unit 190 is configured to use at least one parameter being related to one or more thread consumption parameters 40 to evaluate the thread consumption. The thread consumption parameters 40 comprise parameters 44 related to the substrate or parameters 42 related to the stitches.

The substrate parameters 44 may for example be related to different parameters of the substrate 30. For example, the substrate parameters 44 may relate to the thickness of the substrate 30, the elasticity of the substrate 30, and/or the placement of the substrate in the thread consuming device 15, or any combination thereof. Additionally or alternatively, the substrate parameters may relate to the angle between the stitches, the properties of previous stitches, the stitches arranged beneath or under the upcoming stitches, or any combination thereof.

Different thickness of the substrate 30 will affect the thread consumption. A thicker substrate 30 will require more thread 20, and the thread consumption will thus increase for a thicker (part of a) substrate 30.

The elasticity of the substrate 30 will also affect the thread consumption.

The placement of the substrate in the thread consuming device 15 will also affect the thread consumption. The substrate is often fastened in a frame in order to facilitate the placement of the substrate in the device 15. Different areas of the substrate 30 will be differently tensed depending on where it is located in relation to the frame.

Having a differently tensed substrate will thus affect the thread consumption.

The stitches parameters 42 may be related to the tension of the thread 20, the angle to which the thread 20 is applied to the substrate 30, the angle of at least the last stitch 24, features related to underlying stitches 24, or any combination thereof.

The angle to which the thread 20 is applied to the substrate 30 and/or the angle of the stitches may be used to evaluate the thread consumption. In one embodiment, the angle of the previous stitch is used to evaluate the thread consumption. In one embodiment, the angle between the last two stitches is evaluated. In yet one

embodiment, the mean value of the angle of a predetermined number of stitches is evaluated.

The tension of the thread 20 also affects the thread consumption. More specifically, the balance between the upper thread and the lower thread of the thread consuming device 15 affects the thread consumption. Moreover, the tension between the upper thread and the lower thread and the substrate affects the thread consumption.

The underlying stitches of the substrate (i.e. stitches that already have been sewed and that are arranged on the backside of the substrate) also affect the thread consumption. Underlying stitches arranged with an overlap will require more thread, and thus a higher thread consumption.

Additionally, the length of the stitches is a parameter that may affect the thread consumption. The length of the stitches may be accounted for by the operation data 60 and/or by the thread consumption parameters 40. A method of evaluating the thread consumption is shown in Fig. 7. The control unit 190 is configured to receive or generate 310 operation data and receive or generate 320 at least one parameter being related to one or more thread consumption parameters 40. Based on the operation data and the at least one parameter being related to one or more thread consumption parameters 40, the control unit 190 is configured to evaluate 330 the thread consumption of the thread consuming device 15.

The control unit 190 may further be configured to perform 340 a simulation of the thread consumption and use this simulation data 60 to evaluate the thread consumption, either by using the simulation data 60 to increase the accuracy of the operation data and/or one or more thread consumption parameters 40 and/or to increase the accuracy in the evaluation of the thread consumption.

In one embodiment, the control unit 190 is further configured to use 350 stored data 70 in order to further increase the accuracy of the simulation data and/or to further increase the accuracy of the operation data and/or one or more thread consumption parameters 40.

Once the system 10 has evaluated the thread consumption of the thread consuming device 15, the data is used to control 360 the operation of the system 10. More specifically, the thread consumption is used to control the dispensing from the discharge device 150. Knowing an estimated thread consumption with high accuracy thus reduces the risk of having the wrong coating substance onto the wrong section of the thread 20. In the embodiment where the coating substance is a colouring substance, the thread consumption evaluation reduces the risk of dispensing the wrong colour onto the wrong section of the thread 20, and the generated pattern (or object) onto the substrate 30 will have the desirable appearance.

In one embodiment, the evaluated thread consumption data is, additionally or alternatively, used to control or alter the thread consumption of the thread consuming device 15.

Knowing what factor that affect the thread consumption, allows the control unit 190 to actively control some of these parameters in order to directly change thread consumption. Hence, the system 10 may further be configured to not only change the colour dispensing as been described above, but also, or instead, changing the thread consumption of the thread consuming device. The controlling or altering of the thread consumption may be achieved by controlling the tension of the thread passing into the thread consuming device 15. By e.g. increasing the thread tension, the stitches will consume less thread. By decreasing the thread tension, the stitches will consume more thread. One way of allowing for this will now be described more in detail.

A buffer system comprises at least one thread buffer unit. The thread buffer unit may be in the form of a buffer arm having one end at which the thread is guided. The opposite end may be pivotally attached to a support, such that the position of the thread guiding end may be adjusted. The force applied to the buffer arm will consequently determine the tension of the thread.

The thread buffer unit will allow coated thread to be accumulated, or stored, under tension. The force applied to the thread by the thread buffer unit determines the thread tension, which in most cases will vary depending on the position of the thread buffer unit. Hence, the exact construction of the thread buffer may provide different tensions at different positions along the thread. In an alternative embodiment, the thread buffer unit is constructed so that the force applied to the thread is determined by gravity, by spring(s), combination of gravity and spring(s) or any other device capable of controlling the thread tension. The thread tension is controlled by adjusting the thread buffer unit which pulls the thread through the treatment unit as described above. Controlling the thread buffer unit can thereby control the thread consumption of the thread consuming device.

The thread buffer unit is preferably arranged downstream the at least one discharge device 150. In one embodiment, the buffer is filled up just before a cleaning or maintenance process starts, after which the thread is stopped by the thread feeder 130. In yet one embodiment, the thread buffer is always sufficiently filled. The thread feeder 130 is preferably arranged upstream of the discharge device 150. The amount of thread in the buffer may be adjusted based on the expected thread consumption. The expected thread consumption may preferably take into account any increase in speed of the system 10.

Preferably, the buffer comprises a spring arm that can be configured to require different thread force in the buffer's peak mode (the position where the thread buffer is full) and the bottom of the buffer (empty buffer mode). The control of the thread feeding motor arranged upstream can be used to provide the desired value of the buffer level and thereby changing the thread consumption of the thread consuming device 15, as the buffer level will control the thread tension which in turn affects the thread consumption.

In one embodiment, the active steering of the thread can be applied to the system 10. This solves the problem that a coloured segment of the thread may end up in the wrong location on the substrate 30. Instead of increasing and decreasing the force of the thread being fed into the thread consuming device 15, the information relating to the thread length of a stitch is configured to be used by a thread feeder. The thread feeder will thus feed such length to the thread consuming device 15; the exact length may be estimated or calculated, based on previous estimations/calculations, or by other means related to the above. The information relating to the thread length for a stitch is preferably achieved by simulation data. The thread consuming device 15 is thus forced to use just the intended amount of thread for the stitch. This gives the advantage that the prediction of colours is correctly applied to the substrate.

There might be a risk that the thread will break during usage. It is thus preferred to determine if there is a risk that the thread will break. This risk evaluation can be determined by measuring where, and in what cycle, in the thread consuming device 15 that the fed thread is consumed in the thread consuming device 15. This may be detected by using a suitable sensor, preferably by using the same sensor as in the output thread buffer. If the control unit 190 detects that the thread consuming device 14 consumes the thread earlier than expected, i.e. too early in its cycle, this is indicative that more thread is needed. The opposite also applies, if the control unit 190 detects that the thread consuming device 14 consumes the thread later than expected, i.e. too late in its cycle, this is indicative that less thread is needed. Preferably, suitable threshold limits are defined and average values can be calculated to avoid momentary fluctuations. In case of early detection or late detection, further compensations can be made by adjusting the colour queue of the treatment unit 100 such that the deviant precision in colour change position on the substrate 30 is within preset tolerances. This will allow the system to slowly allowing the system 10 to alter the thread consumption rate into a suitable consumption rate according to the pre-defmed visual effect pattern being requested to occur on the substrate 30. Although the present invention has been mainly described with reference to a system comprising one treatment unit 100 and one thread consuming device 15, it should be understood by a person skilled in the art that the inventive features could be applied to other systems as well. Figs. 8a-b illustrates two example of such alternative systems.

In Fig. 8a, the system 10 comprises a first and a second treatment unit lOOa, lOOb as well as a first and a second thread consuming device l5a-b. Each treatment unit lOOa, lOOb is controlling and performing the operations on each thread consuming device l5a-b. It should be noted that the first and second treatment unit lOOa, although being separated may share one or more components. In one embodiment, the control unit 190 is arranged as a separate unit from the first and second treatment unit lOOa, lOOb and one control unit 190 is thus configured to control the operation of both treatment units lOOa, lOOb and correspondingly the operation of both thread consuming devices l5a-b.

In Fig. 8b, the system 10 comprises one treatment unit lOOa and a first and a second thread consuming device l5a-b. In this embodiment, one treatment unit lOOa is configured to control and perform the operation of the two thread consuming devices l5a-b.

It should be noted that although only two treatment units and two thread consuming devices are shown in Fig. 8a, and only one treatment unit and two thread consuming devices are shown in Fig. 8b, it should be understood that any reasonable number of treatment units and/or thread consuming devices could be present in the system 10.

An embodiment of a system being configured to alter or control the thread consumption of the thread consuming device will now be described. This system 10 comprises one treatment unit 100, two thread consuming devices 10 and two thread consuming regulators (not shown). The thread consuming regulators are arranged to compensate for the difference in thread consumption that can arise between the two (or several) thread consuming devices 15. This provides the advantage that the entire treatment unit 100 can share virtually all components between each other, thus reducing the cost of realizing the solution. Although the present invention has been described above with reference to specific embodiments, it is not intended to be limited to the specific form set forth herein. Rather, the invention is limited only by the accompanying claims.

In the claims, the term“comprises/comprising” does not exclude the presence of other elements or steps. Additionally, although individual features may be included in different claims, these may possibly advantageously be combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. In addition, singular references do not exclude a plurality. The terms“a”, “an”,“first”,“second” etc do not preclude a plurality. Reference signs in the claims are provided merely as a clarifying example and shall not be construed as limiting the scope of the claims in any way.