Title of Invention

A DEVICE FOR SELECTING AND PRESENTING WEFT YARNS TO A GRIPPER OF A RAPIER LOOM

Abstract

The invention relates to a device (16) for selecting and feeding weft yarns (14) to a gripper (11) of a rapier weaving machine. According to the invention, the yam feeder (19) with its drives (20), a diverting guide (31) for the weft yarns (14), and a cutting device (24) form a pre-assembled modular unit that, for adapting to different web widths, is adjustably mounted in the direction of the web width.

Full Text

Device for selecting and feeding weft yarns to a rapier of a rapier loom The invention relates to a device for selecting and presenting weft yarns to a gripper of a rapier loom, having yarn presenters, which may be moved by means of drives from a rest position into a working position, in which they hold a weft yarn in a pick-up position for a gripper, and having a stationary yarn guide, which defines the pick-up position together with in each case one yarn presenter. Conventionally, the yam presenters and the yam guide, as known for example from EP 0161014 B1, are mounted on suitable components of a loom. To effect adaptation to different weaving conditions, such as different cloth widths, different loom speeds and warp yarns of different materials and different thicknesses, the yam presenters and the yam guide are mounted adjustably on the loom. In this construction, a bringer gripper picks up the weft yarns between the selvage and the yam guide and moves together with the weft yam into a shed. P 43461 WO/IN - 2 - It is also known from EP 0906461 B1 that the yam presenters lay the weft yarn to be inserted into a shed over a deflection guide, over which a bringer gripper moves. The feed gripper picks up the weft yarn guided by the deflection guide on both sides of the deflection guide. It is also known (FR 1538375) to form a downwardly sagging loop of weft yarn by lowering a yarn presenter. This loop is located in the movement range of a receiving gripper, i.e., of a gripper which is introduced into a shed from the opposite side of the device for selecting and presenting weft yarns, picks up the selected weft yarn and draws it through the shed. The yarn presenters are arranged in a row one behind the other, which extends parallel to the direction of movement of the gripper. Selection and presenting of the weft yarn to be inserted proceeds by means of a magnet, which may be fed to the individual presenter by means of a cable traction drive acting against a restoring spring. The mount for the yarn presenters and the actuating magnet may be adjusted in a rail transversely of the loom for adaptation to changes in cloth width. The object of the invention is to construct a device of the above-mentioned type in such a way that adjustment operations and in particular adaptation to changes in cloth width are simple to perform. This object is achieved in that the yarn presenters with their drives and the yarn guide constitute a preassembled structure, which may be mounted using fastening means for adjustable mounting of the structural unit on a loom mount extending in the direction of the cloth width. In the event of adaptation to cloth width, only this structural unit has to be adjusted overall. This is a simple operation, which can be readily performed by the operating personnel without any need for in-depth knowledge of the procedures involved. P 43461 WO/IN - 3 - One embodiment of the invention provides for the structural unit to comprise a cutting means for weft yams. Provision of such a cutting means within the structural unit is particularly convenient when the weft yarns to be inserted are held ready in such a way that they extend from a selvage to a delivery means, passing through a yarn guide, in particular an eyelet, of the yarn presenters. In this case, the weft yarn has to be severed at the beginning of the pick from the portion already woven into the cloth. Adaptation to the cloth width is thus likewise necessary for the cutting means. A further embodiment of the invention provides for securing devices in the means for adjustably supporting the yarn guide and/or in the means for adjustably supporting a support for the cutting means or in the means for adjustably supporting the cutting means, ensuring that there is no unauthorised adjustment. In this case, it is provided that the relative adjustment of the yarn presenters relative to the yam guide and/or to the support for the cutting means and/or to the cutting means to the final values is performed at the manufacturer's. The user of the loom is in this case limited merely to adjusting the structural unit for adaptation to changes in cloth width. Further features and advantages of the invention are revealed by the depending claims and in the following description of the exemplary embodiments illustrated in the drawings. Fig. 1 shows a view in the pick direction of a device according to the invention for selecting and presenting of weft yarns, Fig. 2 is a plan view of the device according to the invention according to Fig. 1, P 43461 WO/IN - 4 - Figs. 3-6 show plan views, similar to Fig. 2, of the embodiment according to Figs. 1 and 2 during transfer of a weft yam and the beginning of insertion, Fig. 7 is a view similar to Fig. 1 of a modified embodiment, Fig. 8 is a perspective view of the embodiment according to Fig. 7, Fig. 9 is a view similar to Fig. 1 of a further modified embodiment and Fig. 10 is a plan view of a device according to the invention comprising a temple and a selvage tuck-in device. All that Figs. 1 and 2 show of the actual loom is a rapier 10 in form of a band or a rod, which bears at its end a gripper 11 in the form of a receiving gripper. The loom forms a cloth 15, indicated only schematically, from warp yarns 12, 13 and weft yarns 14. The weft yarns 14 are beaten up with a reed, not shown, to the fell of the cloth. For insertion of a weft yarn 14, the warp yarns are moved apart by means of shedding means, not shown, to form an upper warp yarn sheet 13 and a lower warp yarn sheet 12, such that a shed is formed into which a weft yarn 14 may be inserted, insertion of the weft yarn is performed by means of the receiving gripper 11, which is introduced into the shed from the side opposite from the side on which the weft yarns 14 are kept ready. Upon its movement out of the shed, the receiving gripper 11 in each case carries one weft yarn 14, or optionally also a plurality thereof, with it. The weft yarn 14 to be inserted into a shed during picking is selected by means of a device 16 and fed to the gripper 11. The device 16 has a base member or base place 17, which is attached by means of screws P 43461 WO/IN - 5 - 39 to a profile rail 38 extending in the pick direction. The base plate 17 with the elements attached thereto may be displaced on this profile rail 38 and fixed in a position adapted to the cloth width. The entire device 16 is therefore easily adaptable to changes in cloth width. The device comprises needle-like yarn presenters 19, whose drives 20 are mounted on a support 21 and which extend downwards at an acute angle, such that they can move downwards in a substantially vertical direction. The drives 20 of the yarn presenters 19 may be configured, for example, as is known from EP 0598264 B1, such that the yarn presenters 19 are adjusted between a rest position A (Fig. 1) and a working position B. The yam presenters 19 are each provided at their lower ends with eyelets 22 through which passes in each case one weft yam 14. The weft yarns 14 extend from a selvage of the cloth 15 through the eyelets 22 in each case to a delivery means, for example in each case to a prewinding apparatus (yarn feeder). On the base plate 17 there is mounted a strip 23, on which a yarn severing means 24 is arranged. The yarn severing means 24 has a cutter disk 25, which is driven by means of an electric motor 26. Associated on both sides with the cutter disk 25 are yarn guides, which are formed by means of the strip 23 and guide tongues 28, 29. A further strip 30 is mounted on the base plate 17 of the device 16. Strip 30 forms a deflecting edge 31 by means of an ascending leg, with said deflecting edge 31 extending parallel to the direction of movement of the gripper 11, i.e. transversely of the direction of the warp yarns 12, 13. As is clear from Fig. 1, the deflecting edge 31 lies in a plane with an interlacing point 32 of the cloth 15 and with the yarn guides formed by the strip 23 and the guide tongues 28, 29. P 43461 WO/IN -6- As is clear from Fig. 2, the base plate 17 is adjustable on the profile rail 38 in the direction of the cloth width. The receptacles for fastening screws 39 (Fig. 2) of the base plate 17 are slots directed transversely of the profile rail 38, such that adjustment in the transverse direction is also possible. This adjustment allows the position of the yarn presenters 19 and thus of their eyelets 22 to be adjusted transversely of the gripper 11. The strip 23 with the cutting means 24 is attached to the base plate 17 so as to be adjustable both transversely and in the longitudinal direction relative to the warp yarns. Its position may thus be adjusted relative to the distance to the deflecting edge 31 in the transverse direction and relative to the distance to the end of the deflecting edge 31 in the longitudinal direction thereof. In practice, provision is preferably made for adjustment of the strip 23 with the cutting means 24 and the strip 30 with the deflecting edge 31 relative to one another and to the presenters to be performed at the manufacturer's and for the strips 23, 30 then to be fixed in these positions such that they cannot be changed by the user, or only with some trouble. This may take place, for example, by providing fastening screws with specially designed tool application surfaces. The positions may likewise be lead-sealed. The user of a loom can then only adjust the entire device 16 in the direction of the cloth width and optionally also transversely thereof to a small degree. To ensure that a user cannot straightforwardly effect on his/her loom adjustments of the device 16 in the transverse direction relative to the profile rail 38, it may be provided that adjustability in the transverse direction is separate from fastening to the profile rail 38, such that the device 16 can then only be adjusted on the loom in the cloth width. As is clear from Fig. 1, when the presenters 19 with their eyelets 22 are located in the rest position A, the weft yarns 14 are located above the gripper 11, the deflecting edge 31 and the cutting means 24. If a presenter 19 is moved into its working position B, as is shown in Figs. 2 to 6 for the presenter 19 closest to the selvage, the respective weft yarn P 43461 WO/IN - 7 - 14 is laid over the deflecting edge 31, such that it is located with an obliquely downwardly extending portion 14a beneath the tip 33 of the gripper 11. The gripper 11 passes over this portion 14a and deflects it downwards. If the gripper 11 is moved back again, it grips the yarn portion 14a with its hook-shaped element 34, with which a yarn clamp 35, indicated only schematically in Figs. 2 to 6, is associated. The hook-shaped element 34 and the yarn clamp 35 are located on the side facing the portion 14a of the weft yarn 14, i.e., beneath the top of the gripper 11. The gripper 11 moving back into the shed carries with it the weft yarn picked up at the portion 14a and draws it over the deflecting edge 31 in the direction of the shed. The weft yarn 14 then enters the cutting means 24, in which the weft yarn is severed from the portion remaining at the selvage before it is inserted into the shed. Selection of the weft yarn 14 to be inserted, i.e., transfer of a presenter 19 from its rest position A into its working position B, is controlled by a control device 36, which conveniently constitutes part of the device 16 and is mounted thereon. The control device 36 receives its commands from the loom control system. The control device 36 also switches on the motor 26 of the cutter disk 25. This may take place individually with each pick or continuously at elevated insertion speeds. The yam presenter 19, of which only four are illustrated, are arranged in a row one behind the other. This row runs parallel to the movement path of the gripper 11 and the deflecting edge 31. Since the presenters 19 in each case adopt the same working position B, in side view (Fig. 1), the yarn pieces 14a all extend at the same angle between the eyelets 22 and the deflecting edge 31, even if the angle between the eyelets 22 and P 43461 WO/IN -8- the selvage (Fig. 2) is different. Thus, the gripper 11 always grips the yarn portions 14a in the same way with its hook-shaped element 34 and the clamp 35. In the case of the device according to the invention, the yarn presenters 19 have a downward component within their movement component, such that they lay the weft yarns over the deflecting edge 31. This may take place, as shown in Fig. 1, in that the presenters 19 are oriented at an acute angle. It goes without saying that it is also possible to arrange the presenters in such a way that they are vertically oriented and perform an exclusively vertical movement. As a rule, looms have sufficient space in the direction of the cloth width to arrange a plurality of yarn presenters 19 in a row. However, it is also possible to arrange the yarn presenters 19 in more than one row. In order to achieve the most uniform conditions possible for pick-up of the yarn portions 14a by the gripper 11, it is then advisable to lower somewhat further the yarn presenters 19 of the row arranged at a greater distance from the deflecting edge 31, such that the yarn portions 14a between the eyelets 22 and the deflecting edge 31 extend as far as possible always at the same angle. Differences in angle of a few degrees are readily compensated, however, since the gripper deflects downwards the yarn portion located in the pick-up position. In the embodiment according to Figs. 1 to 6, provision is made for the weft yarns 14 to be separated from the selvage only when they are inserted again into a shed. However, it is also possible to insert each weft yarn into a separating means and separate it on beating-up to the fell. In this case, the free ends are then picked up by a yarn clamp. Such a yarn clamp, which is arranged between the selvage and the cutting means 24, is then a component of the device 16 in such an embodiment. P 43461 WO/IN -9- It should also be pointed out that, in the case of the exemplary embodiment according to Figs. 1 to 7, the device 16 and also the distances between the cutting means 24 and the cloth have been shown exaggeratedly large, to make the illustrations comprehensible. In practice, however, substantially smaller distances are possible, in particular also between the working position B of the yarn presenters and the deflecting edge 31. The embodiment according to Figs. 7 and 8 corresponds in principle to the embodiment according to Figs. 1 to 6. A support 37 inclined in the direction of the deflecting edge 31 is provided for the presenters 19 and their drives 20, such that, overall, shorter needle-like presenters 19 may be used. Another difference consists in the fact that the strip 23 with the cutting means 24 and the strip 30 with the deflecting edge 31 have been combined into an assembly which can only be adjusted jointly relative to the base plate 17 and to the presenters 19. In the exemplary embodiment according to Fig. 9, yarn presenters 19 are provided which may be pivoted between a rest position A and a working position B by means of drives 20 in the form of drive motors. In this embodiment, the eyelets 22 of the yarn presenters 19 move on a movement path which corresponds to a considerable extent to the movement paths of the exemplary embodiments according to Figs. 1 to 6 and Figs. 7 and 8. The shaft 40 of the drive motors is lower than the deflecting edge 31, such that the yarn portion 14a, which is brought into a pick-up position in the movement path of the gripper 11, is well tensioned, as in the other embodiments. In the embodiment according to Fig. 10, first of all, unlike the embodiment according to Figs. 1 and 2, a blade 55 is provided instead of a rotating cutter disk 25, said blade preferably comprising a razor-shape cutting edge. This blade 55, which is easy to replace, is so P 43461 WO/IN -10- oriented that a weft yam 14, which is carried by the gripper 11, slides over the cutting edge of said blade 55 and in the process is cut. This cutting means 24 with the stationary blade 55 does not require a drive. In addition, in the embodiment according to Fig. 10 a support 57 is mounted on the base plate 17, said support bearing a temple 56. The support 57 is fastened to the base plate 17 with adjustable fastening means 59, for example with fastening screws 59, which pass through slot guides in the support 57 and slot guides extending transversely thereof in the base member 17. Likewise, a selvage tuck-in device 58, indicated by broken lines, may also be mounted on the support 57. The selvage tuck-in device 58 may be mounted, in a manner not described in any more detail, on the support 57 using adjustable fastening means. In many cases, it is therefore sufficient, in the event of a change in cloth width, merely to adjust the support 17, wherein at the same time the yarn presenters 19, the cutting means 24, the temple 56 and the selvage tuck-in device 58 are adapted to the change in cloth width. In the exemplary embodiment according to Figs. 1 to 6, the exemplary embodiment according to Figs. 7 and 8 and the exemplary embodiment according to Fig. 9 and also in the exemplary embodiment according to Fig. 10, provision is made for the yarn presenter 19, which is located in working position B, to be returned to an intermediate position between the working position B and the rest position A when the portion 14a of the weft yarn 14 has been picked up by the gripper 11 and inserted into the shed. In this way, it is ensured that the drawing-down of a weft yarn performed by the yarn eyelet 22 located in the intermediate position is not disturbed by the other weft yarns and this weft yarn is held in a favourable position within the shed. P 43461 WO/IN, CN 11 claims 1 A device for selecting and presenting weft yams to a gripper of a rapier loom, having at least one yarn presenter, which may be moved by means of a drive from a rest position into a working position, in which it holds a weft yarn in a pick-up position for a grip-per, and having a stationary yarn guide, which defines the pick-up position together with the yarn gripper, characterised in that the at least one yarn presenter (19) with its drive (20) and the yarn guide (31) constitute a preassembled structural unit, which may be • mounted using fastening means for adjustable mounting of the structural unit on a loom mount (38) extending in the direction of cloth width. 2. A device according to claim 1, characterised in that the structural unit comprises a cutting means (24) for weft yarns. 3. A device according to claim 2, characterised in that the cutting means (24) comprises a cutter disk (25) connected with a drive (26). 4. A device according to any one of claims 1 to 3, characterised in that the structural unit comprises a base member (17) mountable using fastening means on a rail (38), on which base member (17) a support (21, 37) is mounted for the yarn presenters (19) mov- able essentially vertically between the rest position A and the working position B. 5. A device according to any one of claims 1 to 4, characterised in that, in the case of a device installed in a loom, a deflecting edge (31) extending essentially parallel to the direction of movement of P 43461 WO/IN, CN -12- a gripper (11) is mounted on the base member (17) as a yarn guide, and in that the rest position A of the yarn guides (22) of the yarn grippers (19) lies above the deflecting edge (31) and the working position (B) of the yarn guides (22) of the yarn presenters (19) lies below the deflecting edge (31). 6. A device according to claim 5, characterised in that the deflecting edge (31) is mounted on the base member (17) using means which allow adjustment of the deflecting edge in the transverse di rection. 7. A device according to any one of claims 1 to 6, characterised in that there is mounted on the base member (17) a support (23) for the cutting means (24), which is arranged on the side remote from the yarn guides (22) of the yarn presenters (19) relative to the de flecting edge (31). 8. A device according to claim 7, characterised in that the support (23) for the cutting means (24) or the cutting means (24) is mounted using means which allow adjustment transversely of and in the longitudinal direction of the deflecting edge (31). 9. A device according to claim 6 or claim 8, characterised in that the means for mounting the deflecting edge (31) and/or the means for mounting the support (23) for the cutting means (24) or the means for mounting the cutting means (24) comprise securing means en suring against unauthorised adjustment. 10. A device according to any one of claims 1 to 9, characterised in that the yam presenters (19) are arranged stationarily in a row one behind the other, which row extends parallel to the deflecting edge (31). P 43461 WO/IN, CN -13- 11. A device according to any one of claims 1 to 10, characterised in that the preassembled structural unit comprises a temple (56). 12. A device according to any one of claims 1 to 11, characterised in that the preassembled structural unit comprises a selvage tuck-in device (58). 13. A device according to claim 11 or claim 12, characterised in that the temple (56) and/or the selvage tuck-in device (58) are mounted on the base member (17) of the structural unit by means of adjustable holding means (57, 59). The invention relates to a device (16) for selecting and feeding weft yarns (14) to a gripper (11) of a rapier weaving machine. According to the invention, the yam feeder (19) with its drives (20), a diverting guide (31) for the weft yarns (14), and a cutting device (24) form a pre-assembled modular unit that, for adapting to different web widths, is adjustably mounted in the direction of the web width.

Documents:

00840-kolnp-2006 assignment.pdf

00840-kolnp-2006-abstract.pdf

00840-kolnp-2006-claims.pdf

00840-kolnp-2006-correspondence other.pdf

00840-kolnp-2006-description (complete).pdf

00840-kolnp-2006-drawings.pdf

00840-kolnp-2006-form-1.pdf

00840-kolnp-2006-form-2.pdf

00840-kolnp-2006-form-3.pdf

00840-kolnp-2006-form-5.pdf

00840-kolnp-2006-international publication.pdf

00840-kolnp-2006-international search authority report.pdf

00840-kolnp-2006-pct form.pdf

840-KOLNP-2006-CORRESPONDENCE 1.1.pdf

840-KOLNP-2006-FORM 27.pdf

840-KOLNP-2006-FORM-27-1.pdf

840-KOLNP-2006-FORM-27.pdf

840-kolnp-2006-granted-abstract.pdf

840-kolnp-2006-granted-claims.pdf

840-kolnp-2006-granted-correspondence.pdf

840-kolnp-2006-granted-description (complete).pdf

840-kolnp-2006-granted-drawings.pdf

840-kolnp-2006-granted-examination report.pdf

840-kolnp-2006-granted-form 1.pdf

840-kolnp-2006-granted-form 18.pdf

840-kolnp-2006-granted-form 2.pdf

840-kolnp-2006-granted-form 26.pdf

840-kolnp-2006-granted-form 3.pdf

840-kolnp-2006-granted-form 5.pdf

840-kolnp-2006-granted-reply to examination report.pdf

840-kolnp-2006-granted-specification.pdf

840-kolnp-2006-granted-translated copy of priority document.pdf

840-KOLNP-2006-OTHERS.pdf

840-KOLNP-2006-PETITION UNDER RULE 137.pdf

abstract-00840-kolnp-2006.jpg