This application claims the benefit of German patent application DE 10 2010 022 211.9, filed May 20, 2010, herein incorporated by reference.
The invention relates to a yarn sluice for sealing a yarn treating chamber under excess pressure.
It is known to subject yarns, for example after twisting or after cabling, to a thermal treatment and to thus achieve an improvement in the yarn quality. A thermal treatment of this type stabilizes the state of the yarns after the twisting or cabling and frees the yarns from inner torsional forces. Moreover, a thermal treatment of this type leads to a shrink bulking of the yarns, which brings about an increase in the volume of the yarn.
Various methods and mechanisms for the thermal treatment of yarns are described in the patent literature. It has been known, for a long time in this connection, for example, to send yarn wound on bobbins or cops in batches for thermal treatment into steam systems, so-called autoclaves and to thus simultaneously set a large number of bobbins or cops. These known setting devices, however, have the drawback that they require a relatively large amount of space and are also comparatively expensive to acquire. Moreover, qualitative losses of the yarn treated can often not be avoided in these setting devices.
Furthermore, yarn treating devices are known, which are arranged directly in the region of the workstations of twisting machines and with which setting can be carried out on the traveling yarn. There has been success in making the setting process of yarns more economical and efficient using yarn treating devices of this type described, for example, in European Patent Publication EP 1 348 785 A1 or in German Patent Publication DE 103 48 278 A1.
The known devices generally in each case have a yarn treating chamber, into which a gaseous or steam-like treating medium under pressure is blown, the subsequent process of cooling leading to the setting of the yarn. Yarn treating chambers of this type are also equipped with opposing yarn inlet and yarn outlet openings, in the region of which respective sealing devices are installed which seal the yarn treating chamber relative to the environment.
The yarn treating device described in European Patent Publication EP 1 348 785 A1, for example, has sealing devices, which have various rollers, with which pressure losses being produced when the yarn is running into or out of the yarn treating chamber are to be minimised. These sealing devices preferably have drivable outer sluice rollers and inner sealing rollers, which are in each case equipped with a resilient plastics material ring, into which the yarn is pressed when passing the sealing devices.
However, the comparatively wear-sensitive plastics material rings of the sealing rollers are disadvantageous in these sealing devices. The relatively short service life of the plastics material rings requires short service intervals, which has a very negative effect on the efficiency of the yarn treating device.
A yarn treating device is described in German Patent Publication DE 103 48 278 A1, in which the yarn treating chamber, in the region of its yarn inlet and yarn outlet opening, in each case has a yarn sluice with wear-resistant yarn guide elements. In a first embodiment of the yarn sluice, the latter is equipped with two identical, in each case semi-circular, yarn guide elements, which are pressed against one another by a spring element and have, in the region of a common centre longitudinal axis, recesses which form a yarn guide channel. The cross-section of the yarn channel is, in this case, precisely matched to the mean thickness of the yarn to be treated, in other words during operation, the yarn guide channel is sealed by the traveling yarn. When there is a yarn thickening, the yarn guide elements are pressed outwardly against the force of the spring element, so the yarn with the yarn thickening can also pass through the yarn sluice.
In a further embodiment also described in German Patent Publication DE 103 48 278 A1, the yarn guide elements of the yarn sluice are configured in such a way that one of the yarn guide elements is rotatably mounted in the manner of a revolver. In other words, by corresponding positioning of the rotatably mounted yarn guide element, the cross-section of the yarn guide channel can be adjusted. The configuration and arrangement of the yarn guide elements in this case allows a selection to be made between four different cross-sections of the yarn guide channel. In this embodiment as well, one of the yarn guide elements, preferably the rotatably mounted yarn guide element, is arranged in such a way that it can move aside when a yarn thickening occurs.
However, it is disadvantageous in the known yarn sluices that adaptation of the cross-section of the yarn guide channel to the respective thickness of the yarn is often relatively complex or an exact adaptation of the cross-section of the yarn guide channel to the respective yarn diameter is frequently not possible. In other words, in the first embodiment, in the event of a batch change, in which a change is made to a yarn with a different mean thickness, the yarn guide elements also generally have to be replaced, in other words, the installed yarn guide elements have to be replaced in a time-consuming manner by new yarn guide elements which fit the mean thickness of the new yarn.
In the second embodiment as well, in which a selection can be made by the rotatably mounted yarn guide element between four yarn guide channel sizes, difficulties can occur when the yarn has a mean thickness which does not correspond precisely to one of the adjustable yarn guide channel sizes. In other words, in a case such as this, problems are also often produced with regard to a proper sealing of the yarn treating chamber. It has moreover been shown that with the known yarn sluices, in particular with yarn sluices with a rotatably mounted yarn guide element, difficulties occasionally occur when yarn thickenings run through, because, for example, the mounting of the rotatably mounted yarn guide element cannot react sufficiently resiliently to yarn thickenings of this type. Difficulties of this type often result in damaging tensile force increases and problems in the sealing of the yarn guide channel.
Proceeding from the aforementioned prior art, the invention is based on the object of developing a yarn sluice, with which, under all operating conditions, in other words, regardless of the mean thickness of the yarn and the virtually inevitable yarn thickenings, a reliable sealing of a yarn treating chamber can always be ensured during the thermal setting of a yarn.
This object is addressed according to the invention by a yarn sluice for sealing a yarn treating chamber under excess pressure, in which a traveling yarn is thermally treated. The yarn sluice comprises in the region of a yarn inlet opening and a yarn outlet opening of the yarn treating chamber yarn guide elements forming a yarn guide channel which is sealed by the traveling yarn in the operating state. At least one of the yarn guide elements is positionable for adaptation to the mean thickness of the traveling yarn in various, predetermined positions. Means is provided which allows temporary adaptation of the yarn guide channel cross-section to yarn defects. According to the invention, at least one of the first and second yarn guide elements forming the yarn guide channel is steplessly adjustably mounted for adaption to the mean thickness of the yarn to be processed, and a sealing element, which can be placed on the first and the second yarn guide element, extends along the yarn guide channel for closing the yarn guide channel and for reacting resiliently to defects in the traveling yarn.
The configuration of the yarn sluice according to the invention has the advantage that because of the steplessly displaceably mounted first guide element, an exact adaptation of the width of the yarn guide channel to the mean thickness of the yarn to be processed is possible and it is also ensured by the resilient sealing element resting on the yarn guide elements that yarn thickenings can pass through the yarn sluice without causing a notable pressure loss in the yarn treating chamber under excess pressure. In other words, the sealing element resting on the yarn guide elements ensures, on the one hand, that the yarn guide channel is securely closed during operation over its entire length and, on the other hand, the sealing element reacts resiliently to defects in the traveling yarn immediately. By using the resilient sealing element, it is therefore ensured that yarn defects, such as, for example, neps or splices, when running through the yarn sluices, do not lead to a significant tensile force increase nor do sealing problems occur. The sealing element is, in each case, only resiliently deformed by a yarn defect in the region of the yarn defect and, in the process, slightly spaced apart from the yarn guide elements, which merely leads to very small, virtually insignificant pressure losses.
With a yarn sluice configured according to the invention, a secure sealing of the yarn treating chamber, which is under excess pressure, relative to the environment is therefore ensured in all operating states.
In an advantageous embodiment it is provided that the steplessly adjustably mounted first yarn guide element is connected to a drive, which can be activated in a defined manner and is in turn connected to a control and/or a regulating device. A configuration of this type does not only allow a sensitive, very precise positioning of the first yarn guide element and therefore a very precise adjustment of the width of the yarn guide channel to the mean thickness of the yarn, but also good reproducibility of the process, as the yarn guide element at each adjusting process can always be positioned in a precisely predeterminable position that is optimal for the process.
This good reproducibility of the adjustment can be easily realised, in particular when the drive of the yarn sluice is configured as a stepping motor and a sensor device, with which the zero position of the stepping motor can be controlled, is present in the region of the drive.
Stepping motors of this type, as is known, require only a relatively small control outlay with respect to the precise adjustment of their angle of rotation.
In an alternative embodiment, however, it is in principle also possible to manually position the steplessly adjustably mounted yarn guide element. A manual positioning of this type is in fact very economical, but poses the risk of incorrect adjustments occurring. Moreover, a manual positioning of the displaceably mounted yarn guide element is time-consuming.
The steplessly adjustably mounted first yarn element is configured, in an advantageous embodiment, as a yarn guide wedge, which is displaceably mounted in an also wedge-shaped recess of a sluice insert of the yarn sluice. The sluice insert, in this case, also forms the fixed second yarn guide element of a yarn guide channel. As the yarn guide wedge can only move along the oblique contact line of the wedge-shaped recess, it is ensured by a configuration and arrangement of this type that the yarn guide elements forming the yarn guide channel are always oriented parallel to one another, in other words, it is always ensured that the yarn guide channel, in each position of the yarn guide wedge, adopts a width which is the same over the entire length of the yarn guide channel.
The yarn sluice may have a sealing element, which is configured and arranged in such a way that the system pressure prevailing in the yarn sluice acts on the sealing element and keeps it abutting on the yarn guide elements during the yarn treating process.
This ensures that the sealing element over the entire yarn guide channel length is resiliently positioned on the yarn guide channel with a uniform contact pressure.
If necessary, in particular to thread and unthread a yarn into or from the steam setting device, the sealing element of the respective yarn sluice can be positioned without problems spaced apart from the yarn guide elements of the yarn guide channel of the yarn sluice in that an angle lever carrying the sealing element is pneumatically pivoted from its working position into a threading position located slightly spaced apart from the yarn guide elements.
The sealing element resting on the yarn guide elements, which is equipped with a flexible, low-wear sealing band made of a metallic material and has a resilient intermediate insert made of a temperature-resistant resilient material, for example, foam, rubber, silicone rubber or the like, and arranged below the sealing band, during the yarn treatment ensures, on the one hand, that the yarn guide channel is properly closed and, on the other hand, yarn thickenings, such as neps or splices, which are located in the traveling yarn, cannot lead to a tensile force increase, as the resilient intermediate layer of the sealing element when running through a yarn thickening of this type, automatically resiliently moves away in the region of the yarn thickening. In other words, even a yarn which has a yarn thickening can pass through the yarn sluice without problems. As the resilient moving away of the intermediate layer always only takes place in the direct region of the yarn thickening and the sealing band protecting the intermediate layer is held in a sealing manner on the yarn guide elements over the remaining yarn guide channel length by the intermediate layer, the pressure loss of the relevant yarn sluice caused by a yarn thickening is extremely small.
In a particularly advantageous embodiment, the sealing element is configured as a slotted strip, in the receiving slot of which is fixed an H-shaped, resilient intermediate insert, with play. The intermediate insert is also covered here by a flexible, wear-resistant sealing band and thus protected against wear by the traveling yarn. The configuration of the sealing element as a slotted strip, in conjunction with the configuration of the intermediate layer as an H-shaped component, leads to an easily assembleable and very flexible sealing unit, which ensures good sealing of the steam setting device both during regular operation and also during the occurrence of yarn thickenings and, in the process, also prevents tensile force increases occurring on the traveling yarn.
It may be provided that sensors, which monitor the physical variables prevailing in the interior of the yarn treating chamber, such as temperature and/or pressure, are additionally connected to the control and/or the regulating device of the yarn sluice, which inter alfa activates the drive, which can be activated in a defined manner for the steplessly adjustably mounted first yarn guide element. The control and/or the regulating device has a control loop, which by corresponding positioning of the steplessly adjustably mounted first yarn guide element ensures that during the yarn treading process, virtually constant conditions are always maintained in the yarn treating chamber. It is thus ensured that a steam setting device equipped with yarn sluices according to the invention always optimally treats the yarn running through and quality deviations are practically ruled out.
Further details of the invention will be described below with the aid of embodiments shown in the figures, in which:
The workstations 29 also have a control and/or a regulating device 13, which is used to control or regulate the various work components of the workstation 29. As can be seen, a creel thread 18 is fed to a thread 17 drawn off from a twisting pot of the twisting device 15 and is twisted with the latter to form a yarn 14. The yarn 14 arrives via a draw-off device 16 and deflection means 22 at the steam setting device 1, in which, as already indicated above, the yarn 14 is thermally set.
The steam setting device 1, as conventional, substantially consists of a yarn treating chamber 21, which is in turn divided into a central zone 5 and two end zones 6 and 7. The central zone 5 is, in this case, supplied via a connection 8 with a hot, gaseous medium, preferably saturated steam or hot steam, while a cool gaseous medium, for example compressed air, is blown into the end zones 6 and 7, in each case via connections 9A or 9B.
The central zone 5 also has a connection 10, by means of which steam or condensate can be removed. The yarn treating chamber 21 furthermore has a yarn inlet opening 2 in the region of the end zone 6 and a yarn outlet opening 3 in the region of the end zone 7. Arranged in the yarn inlet opening 2 and the yarn outlet opening 3 is, in each case, a yarn sluice 23A or 23B, which seals the yarn treating chamber 21 under excess pressure relative to the environment.
The yarn 14 thermally set in the steam setting device 1 is guided by a draw-off device 11 and deflection means 12 to a winding device 24 of the workstation 29 and wound there to form a cross-wound bobbin 20. The cross-wound bobbin 20 is rotably held here in a pivotable creel (not shown) and rests on a winding roller 19, by means of which it is driven by frictional engagement and is made to rotate in order to wind on the yarn 14.
The hot gaseous medium is fed to the yarn treating chamber 21 of the steam setting device 1 by a steam line (not shown) of the twisting machine. The feeding of the steam may, in this case, be metered by a shut-off device 4 configured as a steam valve and be interrupted if necessary.
As also shown in
The steam setting device 1 is furthermore equipped with a sensor device, the sensors 40, 41, 42, 43 of which are connected by signal lines 39 to the control and regulating device 13. The control and/or regulating device 13 is also connected by control lines 44 to the drives 30 of the yarn sluices 23A and 23B and by signal lines to sensor devices 31 (not shown in
By means of a compressed air connection 49, the yarn sluice 23B can also be loaded with a system pressure which, as will be explained below, acts on a sealing element 28 and ensures that the sealing element 28 is properly positioned on the yarn guide channel 25 of the yarn sluice 23B during the yarn treating process.
A pneumatic cylinder, which ensures during loading that the sealing element 28 during the threading of a yarn 14 can be raised from the yarn guide channel 25, is simultaneously connected to the compressed air connection 50.
As can also be seen from
As can be seen from
As shown in
The rear of the yarn guide channel 25 is formed by the rear wall of the recess 57 of the sluice insert 32, while a sealing element 28 acts as the front wall of the yarn guide channel 25, said sealing element resting resiliently on the yarn guide elements 26, 27 during operation and it being possible to raise it pneumatically from the yarn guide channel 25 to thread in a new twisted yarn 14.
It can clearly be seen here from
Also arranged in the region of the connector 61 is a flexible support disc (not shown), which, in connection with a corresponding sealing film, ensures sealing, in other words, the sealing film prevents the system pressure of the yarn sluice 23 prevailing in the region of the yarn guide elements 26, 27 and the sealing element 28 from being able to be reduced via the groove 60.
Two embodiments are shown in
According to the embodiment of
The lever arm of the angle lever 72 can, however, also be loaded by a small pneumatic cylinder against the force of the spring element. The pneumatic cylinder then ensures that the sealing element 28 is raised from the yarn guide channel 25, which considerably facilitates the threading in of a new twisted yarn.
The sealing element according to
Functioning of the yarn sluice according to the invention:
Before the beginning of the thermal treatment process of a yarn 14 provided by the twisting device 15 in the steam setting device 1, the latter firstly has to be put into its operating state, in other words, the steam setting device 1 has to be heated. Moreover, the width B of the yarn guide channel 25 of the yarn sluices 23A and 23B has to be adjusted in accordance with the mean thickness of the yarn 14 to be processed.
The control and/or regulating device 13, for this purpose, activates the stepping motors 30 of the yarn sluices 23A and 23B in such a way that the adjustably mounted first yarn guide elements 26 of the yarn sluices are positioned in an optimal position for the mean thickness of the yarn to be treated. Furthermore, by actuating corresponding pneumatic cylinders present in the yarn sluices, the sealing elements 28 of the yarn sluices 23A and 23B are raised from the associated yarn guide channels 25.
An injector device 56 is then loaded with compressed air at the yarn sluice 23B located downstream in the yarn running direction, the yarn 14 is pneumatically threaded through the two yarn sluices 23A and 23B and the yarn treating chamber 21 located in between and transferred to the winding device 24.
In the next step, the yarn sluices 23A and 235 are loaded via the connections 49 with a system pressure and simultaneously the pneumatic cylinders at the angle levers 72 of the sealing elements 28 are switched to be without pressure, with the result that the sealing elements 28 are resiliently placed on the yarn guide elements 26, 27 and therefore form yarn guide channels 25, the cross-section of which is optimally adapted to the mean thickness of the yarn 14 to be treated. In other words, the yarn 14 located in the yarn guide channels 25 prevents, for example, hot steam being able to leave the yarn treating chamber 21 and go into the environment via the yarn guide channels 25 of the yarn sluices 23A and 23B. This optimal sealing by the yarn sluices 23A and 235 is also provided when the workstation is then started and a traveling yarn 14 is then thermally treated in the steam setting device 1.
The seal is obviously also maintained when the traveling yarn 14 has a yarn thickening, for example in the form of a nep or a splice and this yarn thickening runs through one of the yarn sluices 23A or 235. In a case such as this, the resilient intermediate layer 34 of the sealing element 28 resting on the yarn guide channel 25 is pressed back slightly by the yarn thickening, so the yarn thickening, without problems, in other words without a significant increase in tensile force, can run through the relevant yarn sluice 23. As the sealing band 33 of the sealing element 28 protecting the intermediate layer 34 is in each case only loaded in the direct region of the yarn thickening, a reliable seal continues to be provided in the remaining regions of the yarn guide channel 25 not affected by the yarn thickening, in other words before and after the yarn thickening, so the pressure loss when a yarn thickening runs through is minimal. The yarn treating chamber 21 is consequently always reliably sealed relative to the environment under all conditions.
It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements, will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof.
Number | Date | Country | Kind |
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10 2010 022 211.9 | May 2010 | DE | national |