Giver rapier head, giver rapier, rapier weaving machine and method for inserting a weft thread in such a rapier weaving machine using such a giver rapier head

Abstract

A giver rapier head (1) comprises a presentation space (9) between a successive guide nose (11), for leading off warp threads (23) on one side (7), and a selection nose (8), for leading off warp threads (23) on the other side, so that a weft thread (2) can be directly presented in this presentation space (9) and can engage from there in an insertion space (15) between the selection nose (8) and the first-mentioned side (7). A giver rapier (1) has a limit guide arc (10) which is arranged at the front side of the giver rapier (1) and a selection nose (8) which is arranged on the top side, with its top (26) facing the guide arc (10). A rapier weaving machine (20) comprises such a giver rapier head (1). In a method for inserting a weft thread (2), the giver rapier head (1) is moved towards this weft thread (2) while the reed (19) beats up an inserted weft thread (2).

Claims

1. Giver rapier head for inserting a weft thread in a rapier weaving machine, comprising: a guide nose which, viewed in the direction of movement for inserting a weft thread, forms the first component of the giver rapier head and which comprises a first guide arc which ends on the bottom side or the top side of the giver rapier head for freely guiding warp threads over said bottom side or top side, wherein the giver rapier head comprises a selection nose which, viewed in said direction of movement, is positioned completely behind the guide nose at an intermediate distance, so that a presentation space extends over a certain distance between the guide nose and the selection nose for presenting therein a weft thread to be inserted to the giver rapier head, wherein said presentation space extends, viewed at right angles to the direction of movement, through the giver rapier head, with an access opening for the weft thread on the top side or the bottom side of the giver rapier head respectively, wherein an insertion space extends between the selection nose and the bottom side or the top side respectively, for allowing the weft thread to engage therein from the presentation space, wherein the selection nose comprises a second guide arc for freely guiding warp threads over the top side or the bottom side respectively, and wherein the point of the guide nose which is furthest from the bottom side or the top side respectively, is situated at least as far from said bottom side or said top side respectively, as the point of the selection nose which is situated furthest from the top side or the bottom side respectively, wherein distance from each nose to each side is measured along a direction which extends at right angles to said direction of movement from the bottom side to the top side.

2. Giver rapier head according to claim 1, characterized in that the guide nose is arranged at the front side of the giver rapier head.

3. Giver rapier head according to claim 1, characterized in that the selection nose is arranged at the front side of the giver rapier head.

4. Giver rapier head according to claim 1, characterized in that the presentation space is suitable for simultaneously presenting several weft threads to be inserted.

5. Giver rapier head according to claim 1, characterized in that the transition of the guide nose from the point of the guide nose, which is positioned furthest from the bottom side or the top side of the giver rapier head respectively, to the presentation space is smooth.

6. Giver rapier head according to claim 1, characterized in that the giver rapier head, at the rear side or the top side or bottom side thereof, comprises a stop to allow the weft thread to strike against it.

7. Giver rapier head according to claim 6, characterized in that the giver rapier head comprises a guide arc at its rear side for guiding the weft thread to said stop.

8. Giver rapier head according to claim 1, characterized in that the giver rapier head is substantially hollow and comprises a movable clamping element for clamping a weft thread which has been gripped behind the selection nose, wherein said clamping element is arranged in the space of the giver rapier head, substantially against the front side of the giver rapier head.

9. Giver rapier comprising a giver rapier head, which is attached to a flexible drive tape or to a rigid drive rod, characterized in that the giver rapier head is a giver rapier head according to claim 1.

10. Rapier weaving machine, comprising a giver rapier head, wherein the giver rapier head is a giver rapier head according to claim 1.

11. Rapier weaving machine according to claim 10, characterized in that the giver rapier head is arranged so as to be displaceable between a first limit position in which a weft thread to be inserted is situated at the location of a central part of this giver rapier head, viewed in the direction of movement for inserting a weft thread, and a second limit position in which the giver rapier head is situated virtually midway along a fabric to be woven using the weaving machine.

12. Rapier weaving machine according to claim 11, characterized in that the weft thread is at the location of the presentation space of this giver rapier head in the first limit position.

13. Rapier weaving machine according to claim 10, characterized in that the rapier weaving machine comprises a reed for beating up an inserted weft thread and comprises a guide element, which is arranged at a fixed position, for guiding a next weft thread to be inserted, which is still attached to the inserted weft thread, when the reed beats up the already inserted weft thread in order to present the next weft thread to be inserted to the giver rapier head.

14. Rapier weaving machine according to claim 13, characterized in that the guide element is configured to guide the next weft thread to be inserted, which is still attached to the inserted weft thread, when the reed beats up the already inserted weft thread in order to present the next weft thread to be inserted over the guide nose of the giver rapier head in the presentation space of the giver rapier head.

15. Rapier weaving machine according to claim 10, characterized in that the rapier weaving machine comprises a cutting device for cutting a weft thread to be inserted from an already inserted weft thread, in which said cutting device is arranged at a fixed position in the rapier weaving machine.

16. Rapier weaving machine according to claim 10, characterized in that the rapier weaving machine comprises a positioning element for positioning a weft thread to be inserted, in which said positioning element is arranged behind the giver rapier head in the rapier weaving machine and is arranged further from the position in the weaving machine where a new fabric to be woven is formed than the giver rapier head.

17. Rapier weaving machine according to claim 16, characterized in that the selection nose of the giver rapier head is arranged substantially according to the direction of the projection of a weft thread which has been presented by said positioning element on the top side of the giver rapier head.

18. Rapier weaving machine according to claim 10, characterized in that the rapier weaving machine is a double-face weaving machine.

19. Method for inserting a weft thread in a rapier weaving machine comprising a reed for beating up an inserted weft thread, wherein the rapier weaving machine is a rapier weaving machine according to claim 10, comprising: moving a next weft thread to be inserted towards the giver rapier head by movement of the reed in order to present it to the giver rapier head when the reed beats up an already inserted weft thread, which is still attached to the next weft thread to be inserted.

20. Method according to claim 19, characterized in that, moving the next weft thread to be inserted comprises situating said weft thread to be inserted at the location of the presentation space, viewed in the direction of movement for inserting a weft thread.

21. Method according to claim 20, characterized in that moving the next weft thread to be inserted comprises presenting the next weft thread to be inserted in the presentation space of the giver rapier head by the movement of the reed.

22. Method according to claim 21, characterized in that, moving the next weft thread to be inserted comprises guiding the weft thread to be inserted over the guide nose of the giver rapier head with the guide element.

23. Method according to claim 22, characterized in that the rapier weaving machine comprises a selection apparatus for selecting a weft thread to be inserted and presenting said weft thread to the giver rapier head, and further comprising only selecting the next weft thread to be inserted with the selection apparatus after an already inserted weft thread has been beaten up by the reed, so that said next weft thread to be inserted is presented in the presentation space of the giver rapier head.

24. Method according to claim 19, further comprising, when the next weft thread to be inserted is moved towards the giver rapier head by the movement of the reed, gripping said weft thread to be inserted underneath the selection nose of the giver rapier head.

25. Method according to claim 19, characterized in that, after the weft thread to be inserted has been gripped behind the selection nose of the giver rapier head and after said weft thread has been clamped by the clamping element, cutting the weft thread to be inserted from the already inserted weft thread with the cutting device.

Description

(1) In this detailed description, reference numerals are used to refer to the attached drawings, in which

(2) FIG. 1 diagrammatically shows a double-face weaving machine in cross section;

(3) FIG. 2 diagrammatically shows in a top view at the location of a first embodiment of a giver rapier head how a giver rapier head according to the present invention may be arranged in a weaving machine with respect to a weft thread to be inserted;

(4) FIG. 3 shows a perspective view of the arrangement from FIG. 2;

(5) FIG. 4 shows the arrangement from FIG. 2 in front view;

(6) FIG. 5 shows the arrangement from FIG. 2 in side view;

(7) FIG. 6 shows a first embodiment of a giver rapier head according to the present invention in front view, in the fitted position, fitted to a drive rod which is only partly shown;

(8) FIG. 7 shows the giver rapier head with part of a drive rod from FIG. 6 in top view;

(9) FIG. 8 shows the giver rapier head with part of a drive rod from FIG. 6 in side view, viewed from the left in FIG. 6;

(10) FIG. 9 shows the giver rapier head with part of a drive rod from FIG. 6 in perspective, viewed from the front left in FIG. 6;

(11) FIG. 10 shows the giver rapier head with part of a drive rod from FIG. 6 in perspective, viewed from the back left in FIG. 6;

(12) FIG. 11 shows the giver rapier head with part of a drive rod from FIG. 6 in perspective, viewed from the front right in FIG. 6;

(13) FIG. 12 diagrammatically shows in top view at the location of a second embodiment of a giver rapier head how a giver rapier head according to the present invention may be arranged in a double-face weaving machine as illustrated in FIG. 1 with respect to a weft thread to be inserted;

(14) FIG. 13 diagrammatically shows the arrangement from FIG. 12 in side view;

(15) FIG. 14 shows a second embodiment of a giver rapier head according to the present invention in bottom view, in the fitted position, fitted to a drive rod which is only partly shown;

(16) FIG. 15 shows the giver rapier head with part of a drive rod from FIG. 14 in front view;

(17) FIG. 16 shows the giver rapier head with part of a drive rod from FIG. 14 in top view;

(18) FIG. 17 shows the giver rapier head with part of a drive rod from FIG. 14 in rear view;

(19) FIG. 18 shows the giver rapier head with part of a drive rod from FIG. 14 in side view, viewed from the left in FIG. 15;

(20) FIG. 19 shows the giver rapier head with part of a drive rod from FIG. 14 in perspective, viewed from the front left in FIG. 15;

(21) FIG. 20 shows the giver rapier head with part of a drive rod from FIG. 14 in perspective, viewed from the back left in FIG. 15;

(22) FIG. 21 shows the giver rapier head with part of a drive rod from FIG. 14 in perspective, viewed from the front right in FIG. 15.

(23) In a double-face weaving machine (20) as illustrated in FIG. 1, warp threads (23) are fed from a warp yarn store at the rear side of the weaving machine (20) (on the right in FIG. 1) to the front side of the weaving machine (20). The warp threads (23) are spread in order to form a top (22) and a bottom shed (22′) in between. A corresponding top giver rapier head (1) and a corresponding bottom giver rapier head (1′) are arranged on one side of the weaving machine (20) in order to be able to introduce weft threads (2) into the top shed (22) and the bottom shed (22′) respectively. After inserting weft threads (2) in the corresponding shed (22, 22′), the inserted weft threads (2) are beaten up against the already woven fabric on the front side of the weaving machine (20) by means of a reed (19). If desired, the position of the warp threads (23) is changed (above-below the shed) in order to form a shed (22) again for inserting a next weft thread (2).

(24) In FIGS. 2 to 21, a top giver rapier head (1) is illustrated in each case. The bottom giver rapier head (1′) may be identical to the top giver rapier head (1), as is illustrated, for example, in FIG. 3 or FIG. 12, provided that the weft threads (2) can be presented in a suitable manner with respect to this bottom giver rapier head (1′). Alternatively, this bottom giver rapier head (1′) may for example also be a mirror image of the top giver rapier head (1) with respect to a virtually horizontal plane between the top shed (22) and the bottom shed (22′) (viewed with respect to the weaving machine (20) as illustrated in FIG. 1). In that case, the means for presenting and cutting the corresponding weft threads (2) are preferably—but not in a limiting way—selected so as to be mirrored with respect to this same horizontal plane. Below, the components of the weaving machine (20) and method for inserting a weft thread (2) are described only in connection with the top giver rapier head (1). It is obvious that this also applies mutatis mutandis to the bottom giver rapier head (1′).

(25) In contrast with the current double-face weaving machines, a weft thread (2) still remains attached to the already woven fabric after inserting a weft thread (2) in a shed (22) until the giver rapier head (1) has gripped this weft thread (2) again. In FIGS. 2, 3, 12 and 13, the situation where this weft thread (2) is still attached to the already woven fabric before the giver rapier head (1) grips this weft thread (2) again can be seen. In FIGS. 2 and 3, the weft thread (2) in this case already extends in the presentation space (9) of the giver rapier head (1). A positioning element (18) for positioning the weft thread (2) is arranged behind and above the giver rapier head (1), so that this weft thread (2) is presented at an angle from above and behind this giver rapier head (1) to underneath and in front of this giver rapier head (1). The top view from FIGS. 2 and 12 shows the angle (α) at which this weft thread (2) in this case extends with respect to the giver rapier head (1). In addition, this positioning element (18) is arranged further from the selvedge of a fabric to be woven using the weaving machine (20) than the giver rapier head (1).

(26) The weaving machine (20) comprises a cutting device (3) for cutting an inserted weft thread (2) which is fixedly arranged in the weaving machine (20). Only after the giver rapier head (1) has gripped this weft thread (2) in order to insert a new piece of weft thread (2) into the shed (22), this weft thread (2) passes the cutting device (3) and is cut thereby.

(27) The first embodiment of a giver rapier head (1) according to the present invention illustrated in FIGS. 2-11 is configured as a hollow, substantially tubular body having a front side (4), a top side (5) a rear side (6) and a bottom side (7).

(28) On its top side (5), this tubular body (1) comprises a small hook-shaped element (14) as a rear stop for the weft thread (2) to strike against.

(29) At its front side (4), the giver rapier head (1) comprises a guide nose (11) which comprises a first guide arc (13) towards the bottom side (7) for freely guiding warp threads (23) over the bottom side (7). This guide nose (11) is arranged as the first component of the giver rapier head (1), viewed in the direction of movement for inserting a weft thread (2). In FIGS. 4, 6 and 7, this is the point (11) to the far left of the giver rapier head (1). Behind the guide nose (11), a presentation space (9) extends for presenting a weft thread (2) to be inserted therein. This presentation space (9) extends through this giver rapier head (1), viewed at right angles to the front side (4), as can be seen in FIG. 6, so that a weft thread (2) can extend freely through this presentation space (9), as can be seen in FIGS. 2 to 5. To this end, this presentation space (9) is provided with an access opening for this weft thread (2) at the top side (5) of the giver rapier head (1). Behind the presentation space (9), a selection nose (8) is arranged at the front side (4) of the giver rapier head (1). This selection nose (8) comprises a second guide arc (10) for freely guiding warp threads (23) over the top side (5) of the giver rapier head (1). To this end, the top point of the guide nose (11) is situated higher than the bottom point of the selection nose (8), so that warp threads (23) which are not conducted away to the bottom side (7) of the giver rapier head (1) via the first guide arc (13) are securely conducted away via the second guide arc (10) on the top side (5) of the giver rapier head (1). Furthermore, an insertion space (15) extends underneath the selection nose (8), between this selection nose (8) and the bottom side (7) of the giver rapier head (1), for allowing the weft thread (2) to engage therein from the presentation space (9). This insertion space (15) is delimited on its right-hand side by a front stop (16) for allowing the weft thread (2) to strike against it.

(30) On its bottom side (7), the giver rapier head (1) is cut at an angle on the right, viewed from its front side (4) to its rear side (6).

(31) On its rear side (6), the giver rapier head (1), adjacent to the bottom side (7), comprises an arc (17) which runs at an angle from the left of its bottom side (7) to the right of its top side (5) and ends adjacent to the hook-shaped element (14) on the top side (5).

(32) The second embodiment of a giver rapier head (1) according to the present invention which is illustrated in FIGS. 12 to 21 is substantially made from sheet material. To this end, a panel-shaped element is folded to form a substantially tubular body having a front side (4), a top side (5), a rear side (6) and a bottom side (7).

(33) At its top side (5), this tubular body comprises a selection nose (8) for gripping the weft thread (2) on the underside thereof.

(34) At its front side (4), the giver rapier head (1) comprises a guide arc (10) for, on the one hand, guiding a weft thread (2) to be inserted under the selection nose (8) and, on the other hand, freely guiding warp threads over the selection nose (8). The guide arc (10) ends in a point (27) which also forms an outermost point of the giver rapier head (1). This point (27) is arranged as the first point (27) of the giver rapier head (1), viewed in a direction of movement of the giver rapier head (1) for inserting a weft thread (2). In FIGS. 14 to 17, this is the far left-hand point (27) of the giver rapier head (1).

(35) The selection nose (8) of the giver rapier head (1) is arranged completely behind the guide arc (10). The top (26) of the selection nose (8) is positioned facing the guide arc (10).

(36) The selection nose (8) of the giver rapier head (1) is substantially positioned according to the direction of the projection of weft thread (2) which is presented with the positioning element (18) on the top side of the giver rapier head (1). As can be seen in FIG. 12, this direction deviates slightly. When beating up the weft thread (2) with the reed (19), this direction will, however, virtually coincide with the arrangement of the selection nose at a certain point in time, following which this direction will deviate in the opposite direction.

(37) A guide slot (15) extends between the selection nose (8) of the giver rapier head (1) and the guide arc (10) of the giver rapier head (1). At the front side, the giver rapier head (1) furthermore comprises a movable clamping element (12) for clamping a weft thread (2) which has been gripped by the giver rapier (1). In addition, the giver rapier head (1) is also provided with a front stop (16) at its front side for a weft thread (2) which has been gripped by the giver rapier head (1) to strike against.

(38) At its bottom side, the giver rapier head (1) is cut at an angle on the right, viewed from its front side to its rear side, so that this bottom side does not protrude further than the selection nose (8) of the giver rapier head (1) on the left-hand side.

(39) On its rear side, the giver rapier head (1) comprises an arc (17) adjacent to the bottom side and running at an angle from the left at its bottom side to the right at its top side.

(40) Between the selection nose (8) and this ascending arc (17), there is a guide slot (28) which ends in rear stop (14) on the top side of the giver rapier head (1).

(41) In both illustrated embodiments, the giver rapier head (1) is provided with several openings (24) in order to make it as lightweight as possible.

(42) In order to incorporate the giver rapier head (1) in a weaving machine (20), the tubular body thereof is fastened to a drive rod (21) in the illustrated figures. This fastening may be achieved in several known ways. Alternatively, the giver rapier head (1) could, for example, also be fastened to a flexible drive tape to this end.

(43) The first embodiment of a giver rapier head (1) is preferably arranged in the weaving machine (20) in such a way that, when the reed (19) beats up an already inserted weft thread which is still attached to a next weft thread (2) to be inserted (which is connected in turn to the weft yarn store), the next weft thread (2) to be inserted is moved towards the giver rapier head (1) by the movement of the reed (19), so that this weft thread (2) to be inserted is taken up to the location of the presentation space (9), as can be seen in FIGS. 2 and 3.

(44) If the weaving machine does not comprise a selection apparatus for selecting a weft thread (2) to be inserted and presenting this weft thread (2) to the giver rapier head (1), then it preferably comprises a guide arc which guides the weft thread (2) over the guide nose (11) into the presentation space (9) during this movement.

(45) If the weaving machine does contain a selection apparatus for selecting a weft thread (2) to be inserted and presenting this weft thread (2) to the giver rapier head (1), then either this weft thread (2) can also be guided via such a guide arc into the presentation space (9) or the selection of the weft thread (2) does not take place until after the reed (19) has beaten up an already inserted weft thread, in order to present the weft thread (2) to be inserted by means of the selection apparatus directly in the presentation space (9).

(46) In contrast to the prior art, the next weft thread (2) to be inserted is always presented in the presentation space (9) and not outside the giver rapier head (1) according to this method. When the giver rapier head (1) advances, the weft thread (2) engages in the insertion space (15) from this presentation space (9). The weft thread (2) is guided further in here until it is situated underneath the movable clamping element (12), is clamped by this clamping element (12) and strikes against the front stop (16). The weft thread (2) is in this case guided further over the guide arc (17) on the rear side of the giver rapier head (1) until it strikes against the rear stop (14).

(47) The second embodiment of a giver rapier head (1) is preferably arranged in the weaving machine (20) in such a manner that when the reed (19) beats up an already inserted weft thread, this is still connected to a next weft thread (2) to be inserted (which is in turn connected to the weft yarn store) by the movement of the reed (19), the next weft thread (2) to be inserted is moved towards the giver rapier head (1), so that this weft thread (2) to be inserted is gripped underneath the selection nose (8) of the giver rapier head (1). FIG. 12 shows a different possible arrangement, in which this is not the case.

(48) In the preferred arrangement, the next weft thread (2) to be inserted will in this case be gripped first underneath the selection nose (8) and will only then touch the guide arc (10). The guide arc (10) guides this weft thread (2) until it touches the bottom side of the selection nose (8). The weft thread (10) is guided further in the guide slot (13) on the rear side of the giver rapier head (1) and reaches the guide slot (15) on the front side of the giver rapier head (1) via the guide arc (10) on the front side of the giver rapier head (1). On the rear side of the giver rapier head (1), the weft thread (2) is guided until it strikes against the rear stop (14). On the front side of the giver rapier head (1), the weft thread (2) is guided further until it is situated underneath the movable clamping element (12), is clamped by this clamping element (12) and strikes against the front stop (16).

(49) When the weft thread (2) to be inserted has been gripped in the above-described preferred manner by the giver rapier head (1) in the two embodiments, the weft thread (2) to be inserted is cut by means of the cutting device (3) from the already inserted weft thread (2).

(50) In the meantime, the reed (19) is moved backwards. Optionally, the warp yarns (23) are repositioned in order to prepare the next shed (22). The giver rapier head (1) is positioned in the shed (22) in order to insert this weft thread (2) to be inserted in this shed (22), transfer it to the taker rapier and return to its starting position in order to pick up a next weft thread (2) to be inserted.

(51) In this way, the insertion cycle for inserting weft threads (2) is continuously repeated.