JP7780870B2 - Method for doffing a yarn package and package doffer - Google Patents

Description

The present invention relates to a method for doffing a yarn package as set forth in the preamble of claim 1 and to a package doffer for receiving and delivering a yarn package as set forth in claim 7.

In a melt spinning process for producing composite yarns, multiple composite yarns are formed at multiple spinning stations. At the end of the process, groups of yarns are wound separately at each spinning station to form a yarn package. Therefore, it is common to have multiple take-up winders arranged alongside one another along a path, each winding multiple yarns to form a yarn package. Once wound by the take-up winders, the yarn package can be received by a portable package doffer and sent along the path. Therefore, methods and package doffers for doffing yarn packages have been known for several years, for example from EP 0 026 471 A1.

In a known method for doffing a yarn package, the receiving mandrel of the package doffer is positioned directly in front of the winding spindle of the take-up winder, allowing it to receive the completed winding of the yarn package onto the winding spindle. After the tensioning device of the winding spindle is released, the yarn package is then pushed from the winding spindle by the pusher of the take-up winder and fed to the receiving mandrel of the package doffer. To prevent loose yarn ends from hanging from the yarn package, an insulated heating wire is assigned to the receiving mandrel of the package doffer. This heating wire guides the yarn package through its interior and melts the hanging yarn ends. However, this results in the formation of residual yarns that are randomly formed on each periphery of the yarn package and, in some cases, are even sucked into the continuous winding process of the take-up winder. Furthermore, the heating wire is positioned in the space surrounding the yarn package, so that loose yarn ends on the yarn package are shortened but remain loose on the yarn package.

Therefore, it is also known in the prior art to fix the loose yarn end of the yarn package to a take-up winder by a package doffer before doffing. Take-up winders of this type are well known in the prior art and are disclosed, for example, in DE 44 13 885 A1. In this respect, each of the multiple take-up winders has a further auxiliary device for fixing the loose yarn end formed on the periphery of the yarn package after winding of the yarn package is complete. Therefore, each take-up winder has a complex auxiliary device that enables doffing of the completely wound yarn package by the package doffer.

It is therefore an object of the present invention to improve a general method for doffing a yarn package and a general package doffer so as to enable reliable doffing of a yarn package from a protruding winding spindle of a take-up winder while substantially eliminating the complexity associated with the take-up winder's equipment.

According to the present invention, this object is achieved by a method for doffing yarn packages, in which loose yarn ends of the yarn packages are fixed to the periphery of the respective yarn packages by a yarn end fixing device of a package doffer installed in a take-up winding machine before the yarn packages are pushed off the winding spindle.

The object of the package doffer of the present invention is achieved by having an apparatus carrier having a movable yarn end fixing device for fixing loose yarn ends on the periphery of the yarn package, and the yarn end fixing device being guideable relative to the apparatus carrier so as to reciprocate between a rest position and an activated operating position.

Advantageous refinements of the invention are defined by the features and feature combinations of the respective dependent claims.

The present invention achieves, on the one hand, reliable doffing of the yarn package from the winding spindle and, on the other hand, the ability to transport the loose yarn end without dropping it. Furthermore, the need to cut off the loose yarn end is advantageously avoided. A particular advantage of the present invention is that it allows the use of multiple conventional take-up winders without additional auxiliary devices for securing the yarn end.

In order to enable the yarn ends of the yarn package to be fixed to the winding spindle immediately after switching of the winding spindle in the take-up winder, a variant of the method is preferably implemented in which a fluid is simultaneously sprayed onto the area of the yarn ends on the periphery of the yarn package while the winding spindle is rotating. Depending on the fluid, even a protective layer can be formed on the yarn package herein, binding and enveloping the loose yarn ends. There is also the possibility of using a liquid adhesive to adhesively bond the loose yarn ends to the periphery of the yarn package only in the area of the tie-down bead. However, from the perspective of further processing, it is preferred to use a fluid consisting of a spin finish.

To this end, the yarn end fixing device of the package doffer according to the present invention has multiple spray nozzles that are spaced apart from one another and connected to a fluid pump and a fluid tank. Therefore, all of the spray nozzles can be operated simultaneously to spray fluid onto the circumferential surface of the yarn package.

The adhesive action of the fluid can be further enhanced by pressing the yarn ends against the periphery of the yarn package with one or more contact pressure rollers, especially if a spin finish is used here.

In this regard, the improved package doffer according to the present invention is preferably used, in which the yarn end fixing device has a plurality of freely rotatable contact pressure rollers spaced apart from one another or a single elongated freely rotatable contact pressure roller extending across the spray nozzle. This allows for improved adhesion of loose yarn ends to the circumferential surface of the yarn package.

The tensioning device of the winding spindle must first be released to allow the yarn package to be doffed from the winding spindle of the take-up winder. For this purpose, a tubular ram, which is usually arranged on the winding spindle, is displaced by compressed air against a spring force. At this point, it is necessary to convey compressed air to the winding spindle. This conveyance is usually carried out by a rotary conveying device of the take-up winder. In this regard, an improvement to the method according to the present invention, in which the relaxation of the tensioning device of the winding spindle is initiated by conveying compressed air from the package doffer to the winding spindle before receiving the yarn package, represents an alternative solution for the purpose of the present invention.

Thus, multiple rotary conveying devices in the take-up winder can be eliminated. The compressed air required to relax the tensioning devices can be provided directly by the package doffer at each of the take-up winder's winding spindles.

For this purpose, the package doffer of the present invention has a compressed air reservoir disposed on the device carrier, to which a movable compressed air adapter is connected, and the compressed air adapter is selectively connectable to the compressed air connector of one of the winding spindles of the take-up winder. Here, the compressed air reservoir can have a compressed air capacity that allows the tension devices of the multiple winding spindles to be relaxed.

Furthermore, a variant of this method in which a package doffer puller is introduced into the take-up spindle to push the yarn package off the winding spindle, and the puller pushes the yarn package around the periphery of the winding spindle, allows for stress relief of the take-up winder during doffing of the yarn package. Therefore, any cooperation between the package doffer controller and the take-up winder controller for doffing the yarn package is reduced to a minimum. The yarn package can be doffed from the winding spindle from its rest position on the winding spindle solely by operation of the package doffer, without the involvement of an auxiliary device in the take-up winder. A further advantage is that the tube relaxation and tube withdrawal can be performed immediately and consecutively by the package doffer controller, resulting in relatively short changeover times.

For this purpose, the package doffer is preferably used in a refinement of the invention in which the device carrier has a movable drawing device which can be guided to move back and forth parallel to the receiving mandrel to a projecting drawing position to acquire the yarn package, and which drawing device has at least one thrust means for guiding the yarn package on one of the winding spindles.

This function of the package doffer can be further improved by shielding the completed winding yarn package from the newly wound yarn package before this function. For this purpose, a movable shielding unit can be used on the device carrier. After the spindle changeover, the shielding unit is pushed between the winding spindles of the take-up winder. The shielding unit is retracted from the take-up winder when the yarn package is withdrawn from the winding spindle.

In order to remove residual yarns and waste yarns that occur during spindle switching or winding from the winding spindle after the yarn package has been doffed, a variant of the method is particularly advantageous in which a package doffer cleaning device is introduced into the take-up winder parallel to the winding spindle after the yarn package has been withdrawn. Thus, residual yarns can be removed from the circumferential surface of the winding spindle mechanically by brushing or non-contact by blowing.

For this purpose, the device carrier has a movable cleaning device that can be guided to move back and forth between a rest position and an operating position relative to the device carrier, and the cleaning device has at least one cleaning means for removing residual yarn from the circumferential surface of one of the winding spindles of the take-up winder. Each of the winding spindles of the take-up winder can thus be cleaned before receiving a new bobbin.

The method according to the present invention for doffing a yarn package is described in more detail below with reference to an exemplary embodiment of a package doffer according to the present invention and with reference to the accompanying drawings.

1 is a schematic side view of an exemplary embodiment of a package doffer according to the present invention; FIG. 1.2 is a schematic side view of the exemplary embodiment of FIG. 1.1 used in front of a take-up winder. FIG. 1.2 is a schematic front view of the exemplary embodiment shown in FIG. 1.1. FIG. 3 is a schematic plan view of the thread anchoring device of the exemplary embodiment of FIGS. 1.1 and 2. 3.2 is a schematic plan view of an alternative exemplary embodiment of the thread end clamping device shown in FIG. 3.1 . FIG. 3 is a schematic cross-sectional view of the compressed air adapter of the exemplary embodiment shown in FIGS. 1.1 and 2. 1.2 is a schematic side view of the exemplary embodiment shown in FIG. 1.1 in use in a take-up winder. 1.2 is a schematic side view of the exemplary embodiment shown in FIG. 1.1 in use in a take-up winder. FIG. 1.2 is a schematic diagram of a portion of the cleaning device of the exemplary embodiment shown in FIG. 1.1.

A first exemplary embodiment of a package doffer according to the present invention is shown schematically in the views of Figures 1.1 and 2. Figure 1.1 shows the exemplary embodiment in a side view, while Figure 2 shows the exemplary embodiment in a front view. Unless explicitly referred to in either view, the following detailed description applies to both views.

In these and the following figures, an exemplary embodiment of the package doffer is identified by the reference numeral 5. The package doffer 5 has a portable device carrier 8, which is self-propelled and remotely controlled by a drive (not shown). A protruding receiving mandrel 6 is arranged on the device carrier 8. In this exemplary embodiment, the receiving mandrel 6 is held on the device carrier 8 by a height-adjustable slide 17. The receiving mandrel 6 is hollow cylindrical and has a compressed air adapter 12 at its free end. The compressed air adapter 12 is connected to a compressed air reservoir 10 by an internal compressed air line 11. The compressed air reservoir 10 is arranged on the device carrier 8 and is shown in dashed lines in FIG. 1.1. The compressed air line 11 and the compressed air adapter 12 are also shown in dashed lines in FIG. 1.1. The function of the compressed air adapter 12 at the free end of the receiving mandrel 6 will be explained below.

Along the receiving spindle 6, the device carrier holds the thread end clamping device 9, the pull-out device 15, and the cleaning device 16. The structure and function of the additional devices provided on the device carrier 8 will be described further below.

The yarn end clamping device 9 has a thrust actuator 9.2, by means of which the yarn end clamping device 9 can be guided to move back and forth between a rest position (as shown in FIG. 1.1) and an activated operating position. The thrust actuator 9.2 is fixedly connected to a holder 9.1 that holds a number of spray nozzles 9.3. The spray nozzles 9.3 are arranged on the holder 9.1 in a predetermined number and at a predetermined distance from each other relative to the thrust actuator 9.2. The distance between the spray nozzles 9.3 and the number of spray nozzles 9.3 on the holder 9.1 are selected depending on the pitch of the take-up winder and the number of winding positions. The yarn package at the winding position is acquired by the package doffer 5.

To further explain the yarn end clamping device 9, further reference is made to FIG. 3.1. The yarn end clamping device 9 is shown diagrammatically in a plan view in FIG. 3.1. As can be seen from FIG. 3.1, the spray nozzles 9.3 are arranged adjacent to one another on a holder 9.1 and are collectively connected to a metering pump 9.5. The metering pump 9.5 is connected to a tank 9.6. The tank 9.6 and the metering pump 9.5 are held in the holder 9.1 in this exemplary embodiment. However, it is also possible in principle to arrange the tank 9.6 or the tank 9.6 and the metering pump 9.5 on the device carrier 8 and to connect the tank 9.6 to the metering pump 9.5 or the spray nozzles 9.6 by means of a flexible line.

As can be seen in Figure 3.1, each spray nozzle 9.3 is assigned to a contact pressure roller 9.4. This contact pressure roller 9.4 is freely rotatable on the holder 9.1 and is mounted so as to extend across all spray nozzles 9.3.

To explain the function of the yarn end clamping device 9, reference is additionally made to FIG. 1.2. The exemplary embodiment of the package doffer of FIG. 1.1 is shown in FIG. 1.2 in operation on a take-up winding machine 1. The take-up winding machine 1 has several winding positions 1.1-1.5 for simultaneously winding several yarns to form yarn packages. For this purpose, the take-up winding machine 1 has two protruding winding spindles 2.1, 2.2. These winding spindles 2.1, 2.2 are held in a winding turret 3. The winding spindles 2.1, 2.2 and the winding turret 3 are driven by a drive 4. Take-up winding machines of this type are well known in the prior art and will not be described further here.

During operation, the yarn package 7 is alternately wound around the winding spindles 2.1 and 2.2. Once the yarn package 7 has reached its final diameter, the winding spindles 2.1 and 2.2 are rotated by the winding turret 3 and guided alternately between the operating area and the switching area. In the situation shown in Figure 1.2, the winding spindle 2.1 is located in the switching area. The yarn package 7 on the winding spindle 2.1 is thus prepared for doffing by the package doffer 5. In the illustrated operating situation, the yarn has already been cut between the winding spindles 2.1 and 2.2, resulting in one loose yarn end being present on each of the completed yarn packages 7.

To enable doffing of the yarn packages 7 from the winding spindle 2.1, the package doffer 5 is positioned in front of the take-up winding machine 1 so that the free end of the winding spindle 2.1 and the free end of the receiving mandrel 6 face each other at a short distance. When the package doffer 5 reaches this position, the yarn end clamping device 9 of the device carrier 8 is activated. A thrust actuator 9.2 guides the holder 9.1 with the spray nozzles 9.3 into the take-up winding machine 1, i.e., from the rest position to the operating position. In the operating position, the yarn end clamping device 9 is arranged so that one spray nozzle 9.3 is assigned to each yarn package 7 and the contact pressure roller 9.4 is supported on the periphery of the yarn package 7. The winding spindle 2.1 is then decelerated. During this procedure, the spray nozzles 9.3 are activated, causing a fluid to be sprayed onto the surface of the yarn package 7 through the spray nozzles 9.3 by the metering pump 9.5. Depending on the fluid and the spray nozzle 9.3, the entire shelf face of the yarn package 7 or only the peripheral restraining beads can be wetted. The yarn ends of the yarn package 7 can be fixed to the shelf face of the yarn package 7 by a contact pressure roller 9.4 supported on the shelf face. A spin finish is preferably used as the fluid. However, it is also possible to use an adhesive fluid that improves the effect of fixing the loose yarn ends to the yarn package 7.

The operating state of the yarn end clamping device 9 in Figure 3.1 is highlighted by the yarn package 7 plotted with a dashed line. Here, the contact pressure roller 9.4 extends over all winding positions or yarn packages 7, respectively. However, it is also possible in principle to clamp the loose yarn end directly on the periphery of the yarn package within a restraining bead. For this purpose, an alternative exemplary embodiment of the yarn end clamping device 9 is shown in Figure 3.2.

In the exemplary embodiment of the yarn end clamping device 9 shown in Figure 3.2, several contact pressure rollers 9.4 are held in a freely rotatable manner in a holder 9.1. Here, one contact pressure roller 9.4 is assigned to each spray nozzle 9.3. The contact pressure rollers 9.4 extend only over a sub-area of the yarn package 7 indicated by the dashed lines, thereby enabling loose yarn ends to be clamped in the area of the clamping bead.

Once the loose yarn end of the yarn package 7 to be doffed has been secured, the yarn end securing device 9 of the device carrier 8 of the package doffer 5 is returned to its rest position. Once the winding spindle 2.1 of the take-up winder 1 has been fully decelerated, a compressed air connection to the winding spindle 2.1 is established by the compressed air adapter 12. This situation is shown diagrammatically in Figure 4.

4 shows a portion of the freely projecting end of the winding spindle 2.1 and the receiving mandrel 6. A compressed air adapter 12 is movably arranged in the receiving mandrel 6 and is connected to an adjustment actuator 13. The compressed air adapter 12 is guided by the adjustment actuator 13 and can be introduced into a compressed air connector 14 at the free end of the winding spindle 2.1. Compressed air is then supplied and introduced into the interior of the winding spindle 2.1 by a control valve. The control valve is not shown here but is arranged in the compressed air reservoir 10. A tensioning device, known, for example, from EP 2 523 884, is configured in the winding spindle 2.1. This will not be further described here, and reference is made to the cited documents. The tensioning mechanism of the tensioning device is released to allow compressed air in the winding spindle 2.1 to doff the winding tube 7.1 of the yarn package 7 from the periphery of the winding spindle 2.1. At this point, the package doffer 5's puller 15 is activated.

As shown in Figures 1.1 and 2, the pulling device 15 has a thrust means 15.1, which can be guided by a thrust actuator 15.2 to move back and forth between a rest position and an operating position. Here, the thrust means 15.1 can pivot relative to the thrust actuator 15.2, for example, so that the yarn package 7 can be pulled from the winding spindle 2.1 by a thrust fork.

Figure 5 shows the situation in which the pulling device 15 is activated to enable the yarn package 7 to be pulled from the winding spindle 2.1. For this purpose, the thrust means 15.1 is guided by the thrust actuator 15.2 so that the yarn packages are successively led from the winding spindle 2.1 to the receiving mandrel 6. Once the last yarn package 7 has been retained on the receiving mandrel 6, the pulling device 15 is guided back to its rest position on the device carrier 8. For this purpose, the thrust means 15.1 is pivoted.

To prepare the winding spindle 2.1 to receive a new tube, the cleaning device 16 of the device carrier 8 is now activated. As can be seen from FIGS. 1.1 and 2, the cleaning device 16 comprises a cleaning means 16.1 and an indexing actuator 16.2. For operation, the cleaning means 16.1 can be moved from a rest position to the take-up winder 1 by the indexing actuator 16.2.

To further explain the cleaning device 16, further reference is made to Figures 6 and 7. A side view of an exemplary embodiment of the package doffer 5 and take-up winder 1 is shown in Figure 6. A portion of the winding spindle 2.1 is shown schematically in Figure 7 together with the cleaning means 16.1. In this respect, reference is made to all figures in the following description.

As can be seen in particular from the view in FIG. 7, the cleaning means 16.1 in this exemplary embodiment is formed by a brush 16.3 pressed against the circumferential surface of the winding spindle 2.1. This brush 16.3 is continuously guided over the entire length of the winding spindle by an indexing actuator 16.2, thereby removing lint and residual thread from the circumferential surface of the winding spindle. The winding spindle 2.1 of the take-up winder 1 is here driven in rotation at a slow speed.

The embodiment of the cleaning device 16 is likewise exemplary. In principle, the cleaning means 16.1 can also have one or more compressed air nozzles, for example to blow off residual threads and thread waste from the circumferential surface of the winding spindle.

The structural embodiment of the additional device of the package doffer 5 shown in the exemplary embodiment according to FIGS. 1.1 and 2 is merely exemplary. The possibility of the package doffer according to the present invention assuming additional functions that would normally have to be performed by auxiliary devices provided in a take-up winder is essential for the method according to the present invention. For example, instead of a spray nozzle to secure loose yarn ends, the yarn end securing device can have a label dispenser for providing a label that is adhesively bonded to the circumferential surface of the yarn package. The compressed air conveying device of the package doffer is particularly advantageous. This compressed air conveying device controls the supply of compressed air to the winding spindle to relax the tensioning device. This eliminates the need for complex rotating conduits in the take-up winder. Furthermore, the yarn package around the circumferential surface of the winding spindle is only released after the package doffer is positioned. Premature release of the yarn package is not possible. The compressed air conveying device of the exemplary embodiment shown in FIG. 1.1 and 2 is likewise exemplary.

The package doffer 5 according to Figures 1.1 and 2 can include a movable shielding unit. This shielding unit is pushed out as an additional device between the winding spindles of the take-up winder during the changeover phase or when doffing the yarn package 7, respectively. This prevents loose yarn ends from being pulled into the first layer of the newly wound yarn package. This makes it possible to eliminate the need for an auxiliary shielding device in the take-up winder.

Claims (12)

1. A method for doffing a yarn package, comprising winding the yarn package onto a protruding winding spindle of a take-up winder having a plurality of winding positions, and receiving the yarn package after winding by a receiving mandrel of a package doffer, comprising:
a yarn end fixing device of the package doffer installed in the take-up winding machine fixing loose yarn ends of the yarn packages to the periphery of each of the yarn packages before the yarn packages are pushed out from the winding spindle. The method of claim 1, characterized in that a fluid is sprayed onto the area of the yarn end on the circumferential surface of the yarn package while the winding spindle is rotating. The method described in claim 2, characterized in that the yarn end is pressed against the peripheral surface of the yarn package by one contact pressure roller or multiple contact pressure rollers. A method according to any one of claims 1 to 3, characterized in that before receiving the yarn package, relaxation of the tensioning device of the winding spindle is initiated by conveying compressed air from the package doffer to the winding spindle. A method according to any one of claims 1 to 4, characterized in that in order to push the yarn package off the winding spindle, a pulling device for the package doffer is introduced into the take-up winding machine parallel to the winding spindle, and the pulling device can push the yarn package over the circumferential surface of the winding spindle. A method according to any one of claims 1 to 5, characterized in that after the yarn package is pulled out, a package doffer cleaning device is introduced into the take-up winder parallel to the winding spindle. A package doffer for receiving and delivering yarn packages (7) held on a plurality of protruding winding spindles (2.1, 2.2) of a take-up winder (1), the package doffer having a movable device carrier (8) on which at least one receiving mandrel (6) for receiving said yarn packages (7) is held,
The package doffer is characterized in that the device carrier (8) has a movable yarn end clamping device (9) for clamping loose yarn ends on the circumferential surface of the yarn package (7), the yarn end clamping device (9) is guideable to reciprocate relative to the device carrier (8) between a rest position and an activated operating position, and the yarn end clamping device (9) is configured to be introduced into the take-up winding machine. The package doffer according to claim 7, characterized in that the yarn end fixing device (9) has a plurality of spray nozzles (9.3) arranged at intervals from one another and connected to a fluid tank (9.6) and a fluid pump (9.5). A package doffer according to claim 7 or 8, characterized in that the yarn end clamping device (9) has a plurality of freely rotatable contact pressure rollers (9.4) spaced apart from one another or a single elongated freely rotatable contact pressure roller (9.4) extending across the spray nozzle (9.3). A package doffer according to any one of claims 7 to 9, characterized in that the device carrier (8) is provided with a compressed air reservoir (10) connected to a movable compressed air adapter (12), the compressed air adapter (12) being selectively connectable to a compressed air connector (14) of one of the winding spindles (2.1, 2.2). 11. The package doffer according to claim 7 or 10, characterized in that the device carrier (8) has a movable drawing device (15) which can be guided to move back and forth parallel to the receiving mandrel (6) to a protruding drawing position to acquire the yarn package (7), and the drawing device (15) has at least one thrust means (15.1) for guiding the yarn package on one of the winding spindles (2.1, 2.2 ). A package doffer according to claim 7 or 10, characterized in that the device carrier (8) has a movable cleaning device (16) that can be guided to move back and forth relative to the device carrier (8) between a rest position and an operating position, and the cleaning device (16) has at least one cleaning means (16.1) for removing residual yarn from the circumferential surface of one of the winding spindles (2.1, 2.2).