Abstract:
A texturing machine for producing a crimped yarn and which has a plurality of serially arranged yarn processing units leading to a takeup device. A threading device is provided for threading a yarn for the first time before the start of a process. For this purpose, the threading device comprises at least one guide tube and an air injector connected thereto, with the guide tube including a suction inlet for receiving the yarn. In accordance with the invention, a cutting device is arranged in the region of the suction inlet of the guide tube, with the cutting device cutting the yarn while being threaded into the suction inlet.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of International Patent Application PCT/EP02/06504 filed Jun. 13, 2002, and which designates the United States. The disclosure of the referenced application is expressly incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates to a texturing machine for producing a crimped yarn. 
     To improve a melt spun yarn, it is known to crimp and draw the flat yarn in a texturing process. To this end, texturing machines are used, which comprise a plurality of processing units as well as a takeup device. The processing units, such as, for example, feed systems, heaters, cooling devices, texturing units, entanglement devices, and yarn lubricators are combined in a machine frame to result in a yarn path, which often extends over two stories of a machine. 
     In the case of such texturing machines, special auxiliary devices are integrated in the texturing machine, so as to make it possible to thread the yarn into the processing units at the beginning of the process. For example, FR 2 695 631 A1 discloses a texturing machine, wherein the yarn is guided by a threading device between a heater and a takeup device. To this end, the threading device includes a plurality of guide tubes, which connect to injectors and guide the yarn pneumatically from the outlet of the heater to the takeup device. 
     However, the texturing machine as disclosed in FR 2 695 631 A1 has the disadvantage that an operator must transfer the advancing yarn from a manually guided suction gun to a suction inlet of a guide tube. In this connection, it is necessary to position the yarn very accurately on the one hand and to cut it at the same time. Missed attempts in the yarn transfer from the suction gun to the guide tube are therefore unavoidable. 
     It is therefore an object of the invention to further develop a texturing machine of the initially described type such that before the start of the process an operator is able to transfer the yarn in a very safe and simple manner to a threading device for advancing the yarn pneumatically. 
     SUMMARY OF THE INVENTION 
     In accordance with the invention, the above and other objects and advantages are achieved by the provision of a texturing machine which includes in the region of the suction inlet of a guide tube a cutting device, which cuts the yarn while it is being threaded into the suction inlet. The special advantage of the invention thus lies in the fact that the operator needs to position only the yarn for enabling a transfer to the threading device. The combination between the cutting device and the suction inlet of the guide tube accomplishes that both the catching of the yarn and the cutting thereof occur automatically, after a manually guided suction gun reaches the threading position. 
     For cutting the yarn, the cutting device may comprise movable or stationary cutting means. Preferably, a stationary cutting blade is used. 
     A particularly advantageous further development of the invention distinguishes itself in that a positioning of the manually guided suction gun is no longer necessary. To transfer the yarn into the suction inlet, the cutting blade of the cutting device is associated with a movable yarn guide. Both the yarn guide and the cutting blade cooperate to thread the yarn into the suction inlet. In this instance, the threading position is assumed by the yarn guide, which thus ensures that the yarn is both cut and taken into the suction inlet. 
     In this connection, it would be possible to form the yarn guide at a free end of an elongate wire strap, so that by pivoting the wire strap the yarn guide reaches the threading position in the range of suction of the suction inlet and cutting device. 
     With the use of a heater with a closed heating channel, it is possible to expand the threading device advantageously by associating the guide tube with the heater, so that the yarn inlet end of the heater forms the suction inlet for threading the yarn, thereby ensuring simultaneously that the yarn is threaded into the heating channel of the heater. 
     Since in the production of the crimped yarn, every contact of the yarn for its guidance causes tensions and an engagement of the yarn, an advantageous further development of the invention provides that the suction inlet of the guide tube or suction inlet of the heater are in alignment with the path of the yarn leaving an upstream feed system. This permits inserting the yarn into the suction inlet directly from the feed system without a further guidance and deflection of the yarn. 
     In a particularly preferred further development of the invention, the feed system is formed by a godet unit, which is looped by the yarn several times, and arranged on a pivotal support that mounts at the same time the yarn guide for threading the yarn. With that, it is possible to thread on the one hand the yarn into the feed system in a simple manner, and to transfer it on the other hand simultaneously to the threading device or suction inlet of the guide tube by pivoting the support. 
     To realize as much as possible a compact construction of the texturing machine, an advantageous further development provides to arrange the guide tube or the heater on the underside of a frame section. This frame section is formed by a processing module mounting at least one portion of the processing units, and by a takeup module mounting the takeup device. The suction inlet of the guide tube could be arranged in the region of the processing module. The yarn would then pneumatically advance through the guide tube to the adjacent takeup module. 
     To guide the yarn as far as the takeup device, at least one second guide tube may be provided with a second injector, the second guide tube being positioned downstream of the first guide tube and immediately upstream of the takeup device. 
     The takeup device preferably includes a suction device, which has an intake opening facing a blow outlet of the second guide tube, preferably in one plane. This permits guiding the yarn automatically into the takeup device. Once the yarn is held in the suction device, for example, a yarn guide could engage the yarn and start a catching or a winding procedure. 
     An advantageous further development is suitable for transferring the yarn in the region of a feed system from a first guide tube to a second guide tube in a highly reliable manner. In this development, the blow outlet of the first guide tube and the suction inlet of the second guide tube face each other in one plane upstream or downstream of a feed system. 
     Once the yarn is transferred, it would be possible to realize an automatic threading of the yarn in the feed system, for example, by a threading device. 
     The method of the present invention is characterized in that it is possible to feed the yarn to a guide tube with a threading device, independently of an operator, in a very safe and reproducible manner. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the following, the invention is described in greater detail with reference to several embodiments of the texturing machine according to the invention and to the attached drawings, in which: 
     FIG. 1 is a schematic view of a first embodiment of the texturing machine according to the invention; 
     FIG. 2 is a schematic view of a further embodiment of the texturing machine according to the invention; and 
     FIG. 3 is a schematic partial view of the embodiment of FIG.  2 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 schematically illustrates a processing station of a yarn texturing machine according to the invention. The texturing machine comprises a plurality of side by side processing stations, in each of which a yarn is textured and wound. Each of the processing stations is thus identically constructed, so that in the following the individual processing units are described with reference to the path of the yarn in one processing station. 
     In a creel  3 , a mandrel  2  mounts a feed yarn package  1 . The feed yarn package  1  holds a flat thermoplastic yarn  36 . From the feed yarn package  1 , the yarn  36  is withdrawn overhead by a first feed system  5 . To this end, a yarn guide  4  is arranged downstream of feed yarn package  1 . From the feed system  5 , the yarn  36  enters a texturing zone. The texturing zone is formed by a texturing unit  8 , a heating device  6 , and a cooling device  7 . In the present embodiment, the texturing unit  8  is realized as a false twist unit, so that the false twist produced in the yarn  36  is set within heater  6  and cooling device  7 . A deflection roll  9  precedes the texturing unit  8 . 
     A second feed system  10  withdraws the yarn  36  from the texturing zone, and advances it into an aftertreatment zone. In the aftertreatment zone, a second heater  11  is provided, which is followed by a third feed system  14 . The feed system  14  is realized as a godet unit comprising a godet  16  and a guide roll  17 . 
     The feed systems  5  and  10  are constructed, for example, as so-called nip-type feed systems, in which the yarn advances between a driven feed roll and a pressure roll lying against the circumference of the feed roll. 
     The feed system  14  is followed by a takeup device  20 . The takeup device  20  comprises a pivotally supported package holder  24 , the free end of which mounts a tube  23 . For winding a package, the tube  23  lies against the circumference of a drive roll  22 , which is driven by a drive at a substantially constant circumferential speed. Upstream of the contact point of yarn  36  on a package is a yarn traversing device  21 , which reciprocates the yarn within the package width. Such yarn traversing devices can comprise a traversing yarn guide, which is driven by a cross-spiraled roll, or a traversing yarn guide, which is driven by a belt drive. 
     To be able to thread the yarn  36  in a processing station at the start of a process, the texturing machine comprises a threading device for pneumatically advancing the yarn  36 . This threading device is essentially formed by guide tubes  12  and  18 . To this end, the guide tube  12  with an injector  13  connects to the outlet of the second heater  11 , thereby forming at the inlet end of heater  11  a suction inlet  33 , through which an air stream is taken in upon activation of injector  13 . The suction inlet  33  in the inlet region of heater  11  is associated with a cutting device consisting of a cutting blade  31  and a holder  32 . The cutting blade  31  is attached to holder  32 . Upstream of the suction inlet  33  and cutting blade  31  is a yarn guide  29 , which connects to an actuator  30 . The actuator  30  is used to move yarn guide  29  in the direction of suction inlet  33 . 
     The guide tube  12  connected to heater  11  comprises at its opposite end a blow outlet  34 . The blow outlet  34  terminates at an inlet end of feed system  14 . Opposite thereto, at the outlet end of feed system  14 , a suction inlet  28  of second guide tube  18  is arranged. In this arrangement, the blow outlet  34  of the first guide tube  12  and the suction inlet  28  of the second guide tube  18  face each other in one plane. The guide tube  18  connects to an injector  19 , which generates in guide tube  18  an air stream that is directed in the direction of the advancing yarn. The guide tube  18  ends directly upstream of takeup device  20 . The blow outlet  27  at the end of guide tube  18  faces, in one plane, an intake opening  26  of a suction device  25 . The suction device  25  is associated with the takeup device  20  for receiving and removing the yarn  36  during package doffs. 
     FIG. 1 shows the processing station of the illustrated embodiment of the texturing machine directly before the start of the process. In this instance, the advancing yarn  36  has already passed through the processing units  5 ,  6 ,  7 ,  8 ,  10 ,  11 , and  14  which are successively arranged in its path. Within the takeup device  20 , the suction device  25  takes in the yarn  36  and removes it to a waste container. 
     For threading the yarn  36 , same is first manually guided by means of a suction gun  35 . Once the yarn  36  is threaded in processing units  5 ,  6 ,  7 ,  8 , and  10 , it is inserted by means of suction gun  35  into a guide groove of yarn guide  29  (shown in phantom lines). This concludes the threading procedure by an operator. The subsequent threading of yarn  36  as far as the takeup device  20  occurs automatically. To this end, the actuator  30  moves the yarn guide  29  in the direction of the suction inlet  33  of heater  11 . In this process, the yarn  36  enters the range of suction of suction inlet  33 . At the same time, the cutting blade  31  of the cutting device cuts the yarn end advancing between suction inlet  33  and the held suction gun  35 . The yarn  36  now advances in guide tube  12  to blow outlet  34 . The yarn  36  that is ejected from guide tube  12 , is taken in by the suction inlet  28  of the second guide tube  18 . With the use of a threading device  15 , it is now possible to thread the yarn  36  that already advances parallel to the feed system  14 , automatically into the godet unit. The threading device  15  could comprise, for example, a pivot drive and a pivotal yarn guide, which threads the yarn into feed system  14  by looping it several times. 
     Once the yarn  36  is received by guide tube  18 , it is ejected from the blow outlet  27  by the air current generated in guide tube  18 , and received by the intake opening  26  of suction device  25 . This concludes the threading procedure of yarn  36  in the processing station of the texturing machine. The process can now be started by pivoting package holder  24  and transferring the yarn to the yarn traversing device  21  or an auxiliary device. 
     In the arrangement shown in FIG. 1, it is also possible to associate the cutting blade  31  with the suction inlet  33  in the inlet region of heater  11  in such a manner that a transfer and cutting of the yarn is already effected by advancing the yarn  36  thereto by means of suction gun  35 . In this case, the yarn guide  29  would not be needed. 
     In the embodiment shown in FIG. 1, the frame sections, which mount the processing units, are left out for the sake of clarity. In contrast, FIG. 2 is a view of an embodiment of the texturing machine according to the invention, which shows the machine frame for accommodating the processing units. The embodiment of the texturing machine of FIG. 2 comprises a feed module  38 , a processing module  39 , and a takeup module  40 , which are arranged in a machine frame with frame sections  37 . 1 ,  37 . 2 ,  37 . 3 . The feed module  38  is supported by frame section  37 . 1 , and the takeup module  40  by frame section  37 . 3 . The frame sections  37 . 1  and  37 . 3  are interconnected by frame section  37 . 2 , which is arranged above feed module  38  and processing module  39 . Between the processing module  39  and feed module  38 , a servicing aisle  42  is formed below frame section  37 . 2 . 
     In the frame section  37 . 2 , the processing module  39  is arranged on the side facing servicing aisle  42  and the takeup module  40  on the opposite side thereof. A doffing aisle  43  is provided along the takeup module  40 . 
     In its longitudinal direction (the drawing plane of FIG. 2 corresponds to the transverse plane), the texturing machine comprises a plurality of processing stations, one for each yarn. The takeup devices  20  occupy a width of three processing stations. For this reason, three takeup devices  20  overlie one another in a column in the takeup module  40 . 
     The processing units arranged in the machine frame  37 , are basically identical with the foregoing embodiment, so that in the following only their essential differences are described. The first feed system  5  on feed module  38  is associated with a creel  3 , which accommodates three feed yarn packages  1 , one above the other. The creel  3  also holds a reserve yarn package in facing relationship with each feed yarn package  1 . In the direction of the advancing yarn, downstream of the first feed system  5 , a heater  6  and a cooling device  7  extend, which are successively arranged in one plane and supported by frame section  37 . 2  above the servicing aisle  42 . In this arrangement, the yarn advances between creel  3 , feed system  5 , and heater  6  over a plurality of deflection rolls  9 . 1 ,  9 . 2 , and  9 . 3 . 
     The processing module  39  mounts, one below the other in the direction of the advancing yarn, a texturing unit  8 , as well as two successive feed systems  10 . 1  and  10 . 2 . 
     On the underside of frame section  37 . 3 , the third feed system  14  on takeup module  40  is arranged in facing relationship with feed system  10 . 2 . From the third feed system  14 , the yarn advances to the takeup device  20 , which is arranged on the takeup module  40 . In comparison with the above-described embodiment, the takeup device  20  includes a tube magazine  41  and auxiliary devices not shown, so as to be able to perform an automatic package doff. 
     For threading the yarn, the frame section  37 . 3  mounts a threading device, which is formed by guide tubes  12  and  18  and their associated injectors  13  and  19 . 
     The suction end of guide tube  12  as well as the feed system  10 . 2  upstream thereof are schematically illustrated in FIG. 3 which is a partial view of FIG.  2 . The feed system  10 . 2  comprises a driven godet  49  and a guide roll  50 , which are arranged on a support  44 . At its one end, the support  44  is held on a pivot axle  46  and can be pivoted between a contacting position and a threading position. FIG. 2 illustrates the support  44  in the threading position, and FIG. 3 shows it shortly before reaching the threading position. The free end of support  44  mounts the yarn guide  29 . In the threading position, the support  44  moves the yarn  29  directly in front of the suction inlet  33  of guide tube  12 . Associated with the suction inlet  33  of guide tube  12  is cutting blade  31 , which is attached to holder  32 . 
     For threading the yarn on feed system  10 . 2 , the support  44  is pivoted to a threading position that extends into servicing aisle  42 , as is shown in phantom lines in FIG.  2 . By means of suction gun  35 , the operator loops the yarn several times about feed system  10 . 2 , and inserts it from its takeoff point on feed system  10 . 2  into the yarn guide  29  at the end of wire strap  45 . Subsequently, the support  44  is pivoted to the threading position, which represents at the same time the operating position of feed system  10 . 2 . In this process, the yarn guide  29  moves the yarn  36  in front of suction inlet  33 . The yarn  36  is then cut by cutting blade  31  in its length that advances toward a suction gun, and pneumatically advanced through guide tube  12 . 
     As shown in FIG. 2, the blow outlet  34  at the end of guide tube  12  faces a deflection plate  48 . Arranged at an angle of about 90° therewith is the suction inlet  28  of the second guide tube  18 . 1 ,  18 . 2 , or  18 . 3 . In the intersections with the blow direction of the first guide tube  12  and with the suction direction in the second guide tube, the deflection plate  48  extends preferably with a deflection curvature corresponding to the direction. This accomplishes that the loose yarn, which is ejected from the blow outlet  34  of guide tube  12 , can be directly taken in by the activated suction inlet  28  of second guide tube  18 . 1 ,  18 . 2 , or  18 . 3 . 
     At its opposite end, the guide tube  18  comprises a blow outlet  27  in facing relationship with a suction system of takeup device  20 , which is not shown. 
     In the texturing machine shown in FIG. 2, the yarn is guided in each processing station through the successively arranged guide tubes  12  and  18 . 1 ,  18 . 2 , and  18 . 3 . In the region of takeup module  40 , successive guide tubes  18 . 1 ,  18 . 2 , and  18 . 3  are shown, which guide a yarn to respective ones of the takeup devices  20 . 
     The embodiments shown in FIGS. 1 and 2 of the texturing machine are exemplary in the arrangement and configuration of the processing units. Basically, it is possible to drive, for example, adjacent feed systems jointly or each by an individual drive. Important is that the arrangement of the processing units in the texturing machine is such that it permits a simple and reproducible threading of the yarn by means of a threading device for advancing the yarn pneumatically. For example, the embodiment of FIG. 2 could be supplemented with a second heater, which would be arranged between the feed systems  10 . 2  and  14 . Likewise possible are additional processing units, such as an entanglement device, which could be arranged between the feed systems  10 . 1  and  10 . 2 , or yarn lubrication devices upstream of the takeup devices  20 . 
     The cutting device shown in the embodiments and consisting of a stationary cutting blade and a holder, is likewise exemplary. The cutting device could also comprise a movable cutting blade, which cooperates, for example, with a stationary yarn guide. It is also possible that the cutting device includes a plurality of cutting blades for cutting the yarn by the operating principle of scissors.