Abstract:
A yarn sluice for sealing a pressurized yarn treating chamber in which a traveling yarn is thermally treated, comprises yarn guide elements in the region of a yarn inlet and outlet openings of the treating chamber forming a yarn guide channel sealed by the traveling yarn during operation. At least one of the guide elements is positionable for adaptation to the mean thickness of the traveling yarn in various predetermined positions. Means is provided for temporary adaptation of the yarn guide channel to yarn defects. At least one of the guide elements ( 26, 27 ) is steplessly adjustably mounted for adaption to the mean thickness of the traveling yarn ( 14 ). A sealing element ( 28 ), which can be placed on the first and the second yarn guide element ( 26, 27 ), extends along the yarn guide channel ( 25 ), for closing it and for reacting resiliently to defects in the traveling yarn ( 14 ).

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of German patent application DE 10 2010 022 211.9, filed May 20, 2010, herein incorporated by reference. 
     FIELD OF THE INVENTION 
     The invention relates to a yarn sluice for sealing a yarn treating chamber under excess pressure. 
     BACKGROUND OF THE INVENTION 
     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. 
     SUMMARY OF THE INVENTION 
     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. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further details of the invention will be described below with the aid of embodiments shown in the figures, in which: 
         FIG. 1  shows a schematic diagram of a workstation of a twisting machine with a steam setting device, the yarn treating chamber of the steam setting device being sealed by yarn sluices according to the invention, 
         FIG. 2  shows the electric motor drive and a part of an associated reducing gear of a yarn sluice, 
         FIG. 3A  shows a front view of a sluice insert of a yarn sluice with a recess for receiving a displaceably mounted yarn guide element, 
         FIG. 3B  shows a perspective view of the sluice insert according to  FIG. 3A  with a steplessly displaceably mounted first yarn guide element arranged in the recess, 
         FIG. 4  shows a side view, partially in section, of a yarn sluice according to the invention, 
         FIG. 5  shows a rear view of the sluice insert of a yarn sluice with a gear arrangement for converting the rotational movement of the electric motor drive into a translatory movement to displace the steplessly displaceably mounted first yarn guide element, 
         FIG. 6  shows a first embodiment of a sealing element, 
         FIG. 7  shows a further, preferred embodiment of a sealing element. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  sketches a schematic view of a workstation  29  of a twisting machine. Textile machines of this type generally have a large number of structurally identical workstations  29  of this type located next to one another. As shown, in the present embodiment, each of the workstations  29  has a steam setting device  1 , which is used to thermally set the yarn  14  drawn off from a twisting device  15 . 
     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  9 A or  9 B. 
     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  23 A or  23 B, 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  FIG. 1 , the steam setting device  1  is also equipped, in each case, with a supply mechanism  37  or a supply mechanism  38  in the region of the yarn inlet opening  2  and in the region of the yarn outlet opening  3 , said supply mechanisms being used to feed the yarn  14  to be treated or to remove the treated yarn  14 . For this purpose, the two supply mechanisms  37 ,  38  are driven in such a way that the yarn  14  running through the steam setting device  1  is held substantially constantly without tension between the supply mechanisms  37 ,  38 . 
     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  23 A and  23 B and by signal lines to sensor devices  31  (not shown in  FIG. 1 ) installed in the region of the drives  30 . 
       FIG. 2  shows one of the yarn sluices  23 A,  23 B, in the embodiment, the yarn sluice  23 B located downstream in the yarn running direction, the superstructure of which, as can be seen, is surrounded by a housing  51 . The yarn sluice  23 B, on the inlet side, has a connection piece  54 , with which it is fixed in the yarn outlet opening  3  of the yarn treating chamber  21  and, on the output side, has an injector device  56 , which can be loaded with compressed air via a connection  50  and allows a pneumatic threading of the yarn  14  through the entire steam setting device  1 . In other words, an airflow, which allows the yarn transportation within the steam setting device  1 , can be initiated within the steam setting device  1  via the compressed air connection  50 . 
     By means of a compressed air connection  49 , the yarn sluice  23 B 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  23 B 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  FIG. 2 , the yarn sluice  23 B also has an electric motor drive  30 , preferably a stepping motor, which is connected by a gear arrangement and a link guide (not shown in  FIG. 2 ) to the steplessly adjustable first yarn guide element  26  of the yarn sluice  23 B. In other words a pinion  45  fastened to the motor shaft of the stepping motor  30  meshes with an intermediate toothed wheel  46 , which in turn drives a relatively large external toothed wheel  47 . The external toothed wheel  47 , as can be seen in particular from  FIG. 4 , is a component of a sleeve-like structural component of the yarn sluice  23 B, this structural component  55  furthermore having a small, coaxially arranged pinion  52 , which meshes with the pinion  64  of a link spindle  53 . Also arranged in the region of the external toothed wheel  47  is a sensor device  31  which preferably consists of a permanent magnet insert  31 A and a Hall element  31 B and monitors the zero position of the drive  30  configured as a stepping motor. The drive  30  is connected by a control line  44  to the control and/or regulating device  13 . 
       FIGS. 3A and 3B  show, in a front view or in a perspective view, a sluice insert  32  arranged within a yarn sluice  23 ,  FIG. 3A  showing the sluice insert  32  without the installed, steplessly adjustably mounted first yarn guide element  26  and  FIG. 3B  showing the sluice insert  32  with said yarn guide element  26 . 
     As can be seen from  FIG. 3A , the sluice insert  32 , on its front side, is configured as a plate-like component, into which a wedge-shaped recess  57  is worked. The plate-like component of the sluice insert  32 , during operation, in this case forms, with its side face  58  pointing to the recess  57 , a fixed second yarn guide element  27  of a yarn guide channel  25 . The opposing side face  59  arranged in a wedge shape of the sluice insert  32  forms a guide for the steplessly adjustably mounted first yarn guide element  26 , not shown in  FIG. 3B , of the yarn sluice  23 . As can be seen from  3 A, the rear of the recess  57  also has a groove  60 , which is arranged parallel to the side face  59  of the recess  57  and in which a connector  61 , as is described in more detail below with the aid of  FIG. 5 , is guided. 
     As shown in  FIG. 3B , the displaceably mounted first yarn guide element  26  is connected by means of a screw bolt  62  to the connector  61  and is guided by the connector  61  in the groove  60  of the sluice insert  32 . The outside  63  of the displaceably mounted first yarn guide element  27  facing the side face  58  of the fixed second yarn guide element  27 , in conjunction with the side face  58 , forms a yarn guide channel  25 . By corresponding positioning, indicated by the arrow H, of the displaceable first yarn guide element  26 , the width B of the yarn guide channel  25  can be steplessly adjusted. 
     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 . 
       FIG. 4  shows a side view, partially in section, of a yarn sluice  23  which, as already indicated above in conjunction with  FIG. 2 , has a sleeve-like structural component  55  with an external toothed wheel  47  and a small, coaxially arranged pinion  52 , which meshes with the pinion  64  of a link spindle  53 . The link spindle  53  has a link guide  65 , to which is connected, by means of a ball head  66 , a guide slide  67  which, as can be seen in particular from  FIG. 5 , is vertically displaceably mounted in the region of the rear of the sluice insert  32  and is secured here by a guide plate  68 . 
     It can clearly be seen here from  FIG. 5 , showing a rear view of the yarn sluice  23 , how the guide slide  67  is connected by a ball head  66 , which is mounted at the end of a connection lever  67 , to the link guide  65  of the link spindle  53 . The guide slide  67  in turn has a slide link  70 , in which the connector  61 , to which the displaceably mounted first yarn guide element  26  is connected, is horizontally displaceably guided. The connector  61  engages, as already indicated above, through the groove  60 , which is worked into the base of the recess  57  parallel to the side face  59  running in a wedge shape, of the recess  57  of the sluice insert  32 . 
     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  FIGS. 6 and 7  for a sealing element  28 , which in each case forms the fourth, resilient limiting wall of the yarn guide channel  25  of the yarn sluice  23 A or  23 B. 
     According to the embodiment of  FIG. 6 , the sealing element  28  has a resilient intermediate layer  34 , which is fastened to the sealing element  28 , and a thin, planar, wear-resistant sealing band  33 , which covers the intermediate layer  34 . The intermediate layer  34  is in this case preferably produced from a temperature-resistant, resilient material, for example foam or the like, while the sealing band  33  is produced from a metal or another abrasion-resistant material. In the embodiment according to  FIG. 6 , the sealing band  33  is mounted at the top in the sealing element  28  and non-positively positioned on the intermediate layer  34 , for example by permanent magnet inserts (not shown), which are arranged in corresponding receivers of the sealing element  28 . As shown, for example, in  FIG. 4 , the sealing element  28  is movably mounted to a limited extent within the yarn sluice  23  by means of a pivot pin  71  on an angle lever  72 , which is in turn connected by a pivot pin  73  to a holder  74 . Arranged within the holder  74  is a spring element (not shown) which loads the angle lever  72  by means of a short lever arm in such a way that the angle lever  72  is pivoted in the direction of the yarn guide channel  25  and the sealing element  28  is thereby positioned on the yarn guide channel  25 , where the sealing element  28  is also loaded with the system pressure of the yarn sluice  23 . 
     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. 
       FIG. 7  shows a further preferred embodiment of a sealing element  28 . As shown in the upper half of  FIG. 7 , the sealing element  28  is configured here as a slotted strip  28 A. The intermediate layer  34 A formed in an H-shape and shown in the lower half of  FIG. 7  can be threaded into the slot of the strip  28 A and is fitted with a relatively large amount of play. The intermediate layer  34 A is in turn covered with a metallic sealing band  33  and thereby protected against abrasion by the traveling yarn  14 . 
     The sealing element according to  FIG. 7 , as described above in connection with  FIG. 6 , is also movably mounted to a limited extent on an angle lever  72  and, for this reason, has a bearing device  75 , which has a corresponding pivot pin  71 . 
     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  23 A and  23 B 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  23 A and  23 B 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  23 A and  23 B are raised from the associated yarn guide channels  25 . 
     An injector device  56  is then loaded with compressed air at the yarn sluice  23 B located downstream in the yarn running direction, the yarn  14  is pneumatically threaded through the two yarn sluices  23 A and  23 B and the yarn treating chamber  21  located in between and transferred to the winding device  24 . 
     In the next step, the yarn sluices  23 A 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  23 A and  23 B. This optimal sealing by the yarn sluices  23 A 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  23 A 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.