US20090293983A1

US20090293983A1 - Apparatus And Method For The Insertion Of A Weft Thread In A Rapier Weaving Machine

Info

Publication number: US20090293983A1
Application number: US12/471,261
Authority: US
Inventors: Marcel Christe
Original assignee: Itema Switzerland Ltd
Current assignee: Itema Switzerland Ltd
Priority date: 2008-05-28
Filing date: 2009-05-22
Publication date: 2009-12-03
Also published as: EP2128317A1; JP2009287160A; CN101613902A

Abstract

An apparatus (1) is presented for the insertion of a weft thread (2) into a shed (10) of a rapier weaving machine. The apparatus (1) includes a rapier tape (3 b) movable in the insertion direction, a rapier head (3 a) at the same and at least one guide part (5) which is provided at the rapier tape or at the rapier head as well as a plurality of guide elements (6.1-6. i+1) which cooperate with the guide part to guide the rapier tape or the rapier head in the shed, wherein the start of the guidance of the guide part by the guide elements is delayed until the rapier tip ( 3 ) is at a distance of at least 14 cm in the shed.

Description

The invention relates to an apparatus and to a method for the insertion of a weft thread into a shed of a rapier weaving machine in accordance with the preamble of claim 1 and with the preamble of claim 6 respectively as well as to a rapier weaving machine having such an apparatus or equipped for the carrying out of such a method.
In rapier weaving machines, the weft thread is usually inserted into a shed by means of a bringer rapier fastened to a rapier rod or to a flexible tape and is taken over and conveyed onward by a taker rapier at a transfer point in the central part of the shed. The bringer rapier has the task of taking up the presented weft thread reliably, of inserting the same into the shed and supplying it precisely to the taker rapier. The taker rapier has the task of taking over the weft thread reliably, conveying the same onward in the shed and releasing it at the end of the weft insertion. Each of the rapiers includes a rapier head which is usually equipped with a thread clamp to clamp the weft thread tight during the weft insertion.
With the numbers of picks usual today, the danger increases that the rapier head deviates from the ideal insertion path and in so doing damages the shed in that it for example, deviates downwardly and in so doing pulls along warp threads from the lower shed or raises upwardly and in so doing pulls along warp threads from the upper shed. In addition, with the current numbers of picks, the reliable transfer of the weft thread from the bringer rapier to the taker rapier becomes more and more difficult. This problem is further amplified by larger cloth widths. A guide is therefore usually provided in current weaving machines which guides the rapier head or the rapier tape during the weft insertion in the shed.
It has been found in this respect that a lateral guidance of the rapier tape at the edges can result in damage to the edges. Fibers are in particular exposed with rapier tapes made of fiber-reinforced plastics due to the friction load at the edges which have a very abrasive effect and can cause warp thread breaks.
A rapier weaving machine having guide teeth for the rapiers is known from EP-A-0 468 916. The guide teeth are made as a sliding support for the rapier tape and for the rapier head and are fastened to a sley of the rapier weaving machine. The rapier head is additionally equipped with a runner which is guided laterally by the guide teeth. Thanks to the runner, the rapier head can be guided laterally without the guide teeth coming into contact with the edges of the rapier tape. In two embodiment variants, the guide teeth engage around the edge of the runner or the runner engages around the edge of the guide teeth such that the rapier head is also guided with respect to the raising.
The rapier weaving machine known from EP-A-0 468 916 has the disadvantage that comparatively little time is available for the braking and accelerating of the sley since the sley has to be in the rear rest position as soon as the rapier head dips into the shed and as long as the rapier head is in the shed on the withdrawal of said rapier head. There is otherwise the risk that the rapier head is deflected by the guide teeth fastened to the sley so that it contacts the warp threads of the shed and may damage them. The braking and accelerating of the sley within a short time results in a comparatively abrupt sley movement by which the bearings and the drive parts of the sley are loaded correspondingly strongly. Furthermore, the maximum achievable number of picks can also be limited by the abrupt sley movement.
It is the object of the invention to provide an apparatus and a method for the insertion of a weft thread into a shed of a rapier weaving machine as well as a rapier weaving machine having such an apparatus or equipped to carry out such a method in which the rapier tape or the rapier head are guided in the shed and by means of which the bearings and drive parts of the sley are loaded less strongly in comparison with the prior art described above.
This object is satisfied in accordance with the invention by the apparatus defined in claim 1 and by the method defined in claim 6 as well as by the rapier weaving machine defined in claim 13.
The apparatus in accordance with the invention for the insertion of a weft thread into a shed of a rapier weaving machine includes a rapier tape movable in the insertion direction, a rapier head at the same and at least one guide part or a guide structure which are provided at the rapier tape and/or at the rapier head as well as a plurality of guide elements which cooperate with the guide part or the guide structure to guide the rapier tape and/or the rapier head in the shed, wherein the start of the guidance of the guide part or of the guide structure by the guide elements is delayed until the rapier tip is at a distance of at least 14 cm or at a distance of at least 18 cm or of at least 24 cm in the shed. The guide elements are advantageously arranged at a sley of the rapier weaving machine.
In an advantageous embodiment variant, the start of the lateral guidance of the guide part or of the guide structure by the guide elements is delayed until the rapier tip is at a distance of at least 14 cm or at a distance of at least 18 cm or of at least 24 cm in the shed. In a further advantageous embodiment variant, the start of the guidance of the guide part or of the guide structure by the guide elements is delayed with respect to the raising until the rapier tip is at a distance of at least 14 cm or at a distance of at least 18 cm or of at least 24 m in the shed.
In a further advantageous embodiment variant, the apparatus includes a rapier tape, a rapier head and at least one guide part or a guide structure for a bringer rapier and/or a rapier tape, a rapier head and at least one guide part or a guide structure for a taker rapier, with the guide part associated with the bringer rapier or the corresponding guide structure being set back by at least 14 cm, in particular at least 18 cm or at least 24 cm, with respect to the rapier tip of the bringer rapier, and/or with the guide part associated with the taker rapier or the corresponding guide structure being set back by at least 14 cm, in particular by at least 18 cm or at least 24 cm, with respect to the rapier tip of the taker rapier.
In a further advantageous embodiment variant, the guide elements for the guidance of the guide part or of the guide structure are offset inwardly by at least 10 cm or are offset inwardly by at least 12 cm or by at least 16 cm with respect to the shed edge.
In an advantageous embodiment, a section is provided at or in the guide part or at or in the guide structure, for example a trapezoidal section or a dovetail section, with the guide elements being made at least in part shape matched to the section of the guide part or of the guide structure to guide the rapier tape and/or the rapier head in the shed by means of the section and of the guide elements.
At least some of the guide elements are advantageously made as one-sided guide elements to guide the guide part or the guide structure respectively on one side and/or to support them on one side. Respective one-sided guide elements are advantageously arranged on both sides of the guide part or of the guide structure to guide the guide part or the guide structure at both sides and/or to support them at both sides, for example in that the one-sided guide elements are arranged alternately.
In a further advantageous embodiment, the start of the guidance of the guide part or of the guide structure by the guide elements is delayed at most for so long until the rapier tip is at a distance of 50 cm or at a distance of 40 cm or of 30 cm in the shed.
In the method in accordance with the invention for the insertion of a weft thread into a shed of a rapier weaving machine, the weft thread is taken up and inserted into the shed by a rapier head which is provided at a rapier tape. Furthermore, at least one guide part or a guide structure is provided at the rapier tape and/or rapier head which cooperate with guide elements to guide the rapier tape and/or the rapier head in the shed, wherein the guide part or the guide structure are only guided by the guide elements when the rapier tip is at a distance of at least 14 cm or at a distance of a least 18 cm or of at least 24 cm in the shed.
In an advantageous embodiment variant, the weaving machine includes a reed which is provided at a sley to beat on an inserted weft thread, wherein the guide part or the guide structure are only guided by the guide elements when the sley is located in the rear rest position. In this respect, the time at which the sley reaches the rear rest position can essentially coincide with the start of the guidance of the guide part or of the guide structure by the guide elements.
In a further advantageous embodiment variant, the weft thread is taken up and inserted into the shed by a rapier head of a bringer rapier which is provided at a rapier tape and/or is taken over and conveyed onward by a rapier head of a taker rapier which is provided at a rapier tape. In addition, in each case at least one guide part or a guide structure are provided at the rapier tape and/or rapier head of the bringer rapier or of the taker rapier respectively which cooperate with guide elements to guide the respective rapier tape and/or the respective rapier head in the shed, wherein the guide part associated with the bringer rapier or the corresponding guide structure are set back by at least 14 cm, in particular at least 18 cm or at least 24 cm, with respect to the rapier tip of the bringer rapier, and/or wherein the guide part associated with the taker rapier or the corresponding guide structure are set back by at least 14 cm, in particular at least 18 cm or at least 24 cm, with respect to the rapier tip of the taker rapier.
In a further advantageous embodiment variant, the guide elements for the guidance of the guide part or of the guide structure are offset inwardly by at least 10 cm or are offset inwardly by at least 12 cm or by at least 16 cm with respect to the shed edge.
In an advantageous embodiment of the method, a section is provided at or in the guide part or at or in the guide structure, for example a trapezoidal section or a dovetail section, with the guide elements being made at least in part shape matched to the section of the guide part or of the guide structure to guide the rapier tape and/or the rapier head in the shed by means of the section and of the guide elements.
Advantageously, at least some of the guide elements are made as one-sided guide elements which guide the guide part or the guide structure on one side respectively and/or support them on one side, wherein respective one-sided guide elements are arranged on both sides of the guide part or of the guide structure to guide and/or support the guide part or the guide structure on both sides, and wherein the one-sided guide elements are arranged alternately, for example.
In a further advantageous embodiment of the method, the guide part or the guide structure are guided by the guide elements at the latest when the rapier tip is at a distance of 50 cm, in particular at a distance of 40 cm or of 30 cm, in the shed.
The invention furthermore includes a rapier weaving machine having an apparatus in accordance with one of the embodiment variants and embodiments described above and/or equipped to carry out a method in accordance with the above description.
In an advantageous embodiment variant, the rapier weaving machine includes a sley with a reed to beat on an inserted weft thread, wherein the start of the guidance of the guide part or of the guide structure by the guide elements is not before the time at which the sley has reached the rear rest position. In this respect, the start of the guidance of the guide part or of the guide structure by the guide elements can essentially coincide with the time at which the sley has reached the rear rest position.
The apparatus and the method in accordance with the present invention as well as the rapier weaving machine in accordance with the invention have the advantage with respect to the described prior art that, thanks to the delayed start of the guidance of the rapier tape and/or rapier head in the shed, the rapier head can already be introduced into the shed before the sley has reached the rear rest position without there being any risk that the rapier tape and/or the rapier head is deflected by moving guide elements and damages the warp threads. In this respect, the rapier tape and/or the rapier head can subsequently, when the sley is in the rear rest position, still be guided reliably in the shed, and indeed optionally laterally and/or with respect to downward and/or upward deviations.
Conversely, the guidance of the rapier tape and/or rapier head ends in accordance with the invention in the second half of the weft insertion on the withdrawal of the rapier head from the shed before the rapier head has left the shed. The time duration or the machine angular range during which the rapier tape and/or the rapier head are guided in the shed can thus be shortened both in the first and the second half of the weft insertion with respect to the apparatus and methods known from the prior art so that a correspondingly longer time portion or machine angular range is available for the sley movement for the beating on of the inserted weft thread. The longer machine angular range, which is available thanks to the apparatus in accordance with the invention and to the method in accordance with the invention, allows the sley movement to be carried out less abruptly, whereby the bearings and the drive parts of the sley are saved and/or can be made lighter.
The above description of embodiments and embodiment variants only serves as an example. Further advantageous embodiments and embodiment variants can be seen from the dependent claims and from the drawing. Furthermore, individual features from the embodiments and embodiment variants described or shown can also be combined with one another within the framework of the present invention to form new embodiments.

The invention will be explained in more detail in the following with reference to the embodiment and to the drawing. There are shown:

FIG. 1 a detail of a rapier weaving machine having an apparatus for the insertion of a weft thread in accordance with the present invention;

FIG. 2 an embodiment of an apparatus in accordance with the present invention in a slanted view;

FIG. 3 a cross-section through the embodiment of FIG. 2;

FIG. 4 a side view of the embodiment of FIG. 2;

FIG. 5 a further embodiment of an apparatus in accordance with the present invention;

FIG. 6 a graphic representation of the rapier movement for an embodiment in accordance with the present invention;

FIG. 7A a graphic representation of the sley movement for a conventional apparatus for the insertion of a weft thread; and

FIG. 7B a graphic representation of the sley movement for an embodiment in accordance with the present invention.

FIG. 1 shows a detail of a rapier weaving machine having an apparatus 1 for the insertion of a weft thread 2 in accordance with the present invention. The rapier weaving machine can include, for example, a reed 8 for the beating on of inserted weft threads and a thread stock 2 a from which the weft thread 2 is removed on insertion. Furthermore, the rapier weaving machine can include a shed forming device which can be equipped, for example, with healds 7 a, 7 b to raise some of the warp threads 12 a, 12 b and simultaneously to lower some further warp threads so that a shed 10 is formed between the raised and lowered warp threads. The apparatus 1 typically includes a rapier tape 3 b movable in the insertion direction and a rapier head 3 a for a bringer rapier to insert the weft thread 2 into the shed 10 and a rapier tape 4 b movable in the insertion direction and a rapier head 4 a for a taker rapier to take over and convey onward the weft thread from the bringer rapier in the central region of the shed. Possible aspects of the apparatus 1 will be looked at in more detail in the following paragraphs.
FIG. 2 shows an embodiment of an apparatus in accordance with the present invention in a slanted view. FIGS. 3 and 4 show the same embodiment in cross-section and in a side view. In the embodiment shown in FIGS. 2 to 4, the apparatus 1 includes a rapier tape 3 b movable in the insertion direction, a rapier head 3 a at the same and at least one guide part or a guide structure 5 which are provided at the rapier tape and/or at the rapier head as well as a plurality of guide elements 6.1-6.i+1 which cooperate with the guide part or the guide structure to guide the rapier tape and/or the rapier head in the shed. In this respect, the rapier tape and/or the rapier head can be guided in the shed as required with respect to downward deviations and/or with respect to upward deviations and/or laterally. In the apparatus in accordance with the invention, the start of the guidance of the guide part or of the guide structure by the guide elements is delayed until the rapier tip 3 is at a distance of at least 14 cm or of at least 18 cm, of at least 24 cm or of at least 30 cm in the shed 10, i.e. the guidance of the guide part or of the guide structure by the guide elements only starts when the rapier tip has dipped into the shed, measured from the shed edge or the reed edge, to a distance of at least 14 cm, 18 cm, 24 cm or 30 cm. In an advantageous embodiment variant, the start of the lateral guidance of the guide part or of the guide structure 5 by the guide elements 6.1-6.i+1 is delayed until the rapier tip is at a distance of at least 14 cm or at a distance of at least 18 cm, of at least 24 cm or of at least 30 cm in the shed 10. In a further advantageous embodiment variant, the start of the guidance of the guide part or of the guide structure by the guide elements is delayed with respect to the raising until the rapier tip is at a distance of at least 14 cm or at a distance of at least 18 cm or of at least 24 cm or of at least 30 cm in the shed 10.
The rapier weaving machine in which the apparatus 1 is used can, for example, include a sley 9 and, at the same, a reed 8 for the beating on of inserted weft threads. The guide elements 6.1-6.i+1, as shown in FIGS. 2 and 3, are advantageously arranged at and/or fastened to the sley 9 of the rapier weaving machine. Furthermore, the rapier weaving machine can include a shed forming device, for example as shown in FIG. 2, a shed forming device having healds 7 a, 7 b to raise some of the warp threads 12 b and simultaneously to lower some further warp threads 12 a and to form a shed 10 between the raised and lowered warp threads.
In a further advantageous embodiment variant, the apparatus 1 includes a rapier tape 3 b, a rapier head 3 a and at least one guide part or a guide structure 5 for a bringer rapier 3 and/or a rapier tape 4 b, a rapier head 4 a and at least one guide part or a guide structure for a taker rapier, with the guide part associated with the bringer rapier or the corresponding guide structure being set back by at least 14 cm, or at least 18 cm or at least 24 cm or at least 30 cm with respect to the rapier tip 3 of the bringer rapier, and/or with the guide part associated with the taker rapier or the corresponding guide structure being set back by at least 14 cm, or at least 18 cm or at least 24 cm or at least 30 cm with respect to the rapier tip 4 .
In an advantageous embodiment, a section is provided at or in the guide part or at or in the guide structure 5, for example, as shown in FIG. 2, a trapezoidal section or a dovetail section, with the guide elements 6.1-6.i+1 being formed at least in part shape matched to the section of the guide part or of the guide structure to guide the rapier tape 3 b and/or the rapier head 3 a in the shed 10 by means of the section and of the guide elements. Sections, which are arranged downwardly at the rapier tape and/or rapier head and which, like the trapezoidal section or the dovetail section, have portions which taper upwardly, have the advantage that not only a lateral guidance or a guidance with respect to downward deviations is thus possible, but also a guidance against raising upwardly without the guide elements having to engage around the guide elements for this purpose.
Advantageously, at least some of the guide elements or, as shown in FIGS. 2 to 4, all the guide elements 6.1-6.i+1 are made as one-sided guide elements which respectively guide the guide part or the guide structure 5 on one side and/or support them on one side.
Advantageously, respective one-sided guide elements are arranged on both sides of the guide part or of the guide structure to guide the guide part or the guide structure at both sides and/or to support them at both sides, for example in that the one-sided guide elements are arranged alternately.
In a further advantageous embodiment, the start of the guidance of the guide part or of the guide structure 5 by the guide elements 6.1-6.i+1 is delayed at most for so long until the rapier tip 3 is at a distance of 50 cm or at a distance of 40 cm or of 30 cm in the shed, in particular measured from the shed edge or reed edge, at a distance of 50 cm or at a distance of 40 cm or of 30 cm in the shed.
FIG. 5 shows a further embodiment of an apparatus in accordance with the present invention. In the embodiment shown in FIG. 5, the apparatus 1 includes a rapier tape 3 b movable in the insertion direction, a rapier head 3 a at the same and at least one guide part or a guide structure 5 which are provided at the rapier tape and/or at the rapier head as well as a plurality of guide elements 6.1-6.3 which cooperate with the guide part or the guide structure to guide the rapier tape and/or the rapier head in the shed. In this respect, the rapier tape and/or the rapier head in the shed can be guided as required with respect to downward deviations and/or with respect to upward deviations and/or laterally. In this embodiment, the guide elements for the guidance of the guide part or of the guide structure are offset inwardly by at least 10 cm or by at least 12 cm or by at least 16 cm with respect to the shed edge, which normally coincides with the outermost reed dents of the reed 8 so that no guide elements are present in the outermost 10 cm, 12 cm or 16 cm of the shed in the variant shown in FIG. 5. If required, guide elements can be provided in the outermost 10 cm, 12 cm or 16 cm of the shed which only support the rapier tape and/or the rapier head, i.e. guide with respect to downward deviations. As the case may be, as shown in FIG. 5, the guide part or the corresponding guide structure 5 can also be set back by at least 14 cm, or at least 18 cm, at least 24 cm or at least 30 cm with respect to the rapier tip 3 in this embodiment.
The examples, embodiments and embodiment variants shown in FIGS. 2 to 5 and described above usually refer to a bringer rapier. The examples, embodiments and embodiment variants shown and described above can naturally also be used in a corresponding manner and with the same advantages for a taker rapier.
An embodiment of the method in accordance with the invention for the insertion of a weft thread 2 into a shed 10 of a rapier weaving machine will be described in the following with reference to FIGS. 2 to 4. In the embodiment, the weft thread is taken up and inserted into the shed by a rapier head 3 a, which is provided at a rapier tape 3 b, for example, by means of a thread clamp which is provided in the rapier head. Furthermore, at least one guide part or a guide structure 5 are provided at the rapier tape and/or rapier head which cooperate with guide elements 6.1-6.i+1 to guide the rapier tape and/or the rapier head in the shed, with the guide part or the guide structure only being guided by the guide elements when the rapier tip 3 is at a distance of at least 14 cm or at a distance of at least 18 cm or of at least 24 cm or of at least 30 cm in the shed, in particular measured from the shed edge or the reed edge, at a distance of at least 14 cm or at a distance of at least 18 cm or of at least 24 cm or of at least 30 cm in the shed. In this respect, the rapier tape and/or the rapier head in the shed can be guided as required with respect to downward deviations and/or with respect to raising upwardly and/or laterally. In an advantageous embodiment variant, the guide part or the guide structure are only guided laterally and/or with respect to the raising by the guide elements when the rapier tip is at a distance of at least 14 cm or at a distance of at least 18 cm or of at least 24 cm or of at least 30 cm in the shed.
In a further advantageous embodiment variant, the weaving machine includes a reed 8 which is provided at a sley 9 to beat on an inserted weft thread, with the guide part or the guide structure 5 only being guided by the guide elements 6.1-6.i+1 when the sley is in the rear rest position. In this respect, the time at which the sley reaches the rear rest position can essentially coincide with the start of the guidance of the guide part or of the guide structure by the guide elements.
In a further advantageous embodiment variant, the weft thread 2 is taken up and inserted into the shed 10 by a rapier head 3 a of a bringer rapier 3, which is provided at a rapier tape 3 b, and/or is taken over and conveyed onward by a rapier head of a taker rapier which is provided at a rapier tape. In addition, in each case at least one guide part or a guide structure 5 are provided at the rapier tape and/or rapier head of the bringer rapier or of the taker rapier respectively which cooperate with guide elements 6.1-6.i+1 to guide the respective rapier tape and/or the respective rapier head in the shed, with the guide part associated with the bringer rapier or the corresponding guide structure being set back by at least 14 cm, at least 18 cm, at least 24 cm or at least 30 cm, with respect to the rapier tip 3 of the bringer rapier, and/or with the guide part associated with the taker rapier or the corresponding guide structure being set back by at least 14 cm, at least 18 cm, at least 24 cm or at least 30 cm, with respect to the rapier tip of the taker rapier.
In an advantageous embodiment of the method, a section is provided at or in the guide part or at or in the guide structure 5, for example a trapezoidal section or a dovetail section, with the guide elements 6.1-6.i+1 being formed at least in part shape matched to the section of the guide part or of the guide structure to guide the rapier tape and/or the rapier head in the shed by means of the section and of the guide elements.
Advantageously, at least some of the guide elements 6.1-6.i+1 are made as one-sided guide elements which guide the guide part or the guide structure on a respective side and/or support them on one side, with respective one-sided guide elements being arranged on both sides of the guide part or of the guide structure to guide and/or support the guide part or the guide structure on both sides, and with the one-sided guide elements being arranged alternately, for example, as shown in FIGS. 2 and 3.
In a further advantageous embodiment of the method, the guide part or the guide structure 5 are guided by the guide elements 6.1-6.i+1 at the latest when the rapier tip 3 is at a distance of 50 cm or at a distance of 40 cm or of 30 cm in the shed, in particular measured from the shed edge or the reed edge, at a distance of 50 cm or at a distance of 40 cm or of 30 cm in the shed.
A second embodiment of the method in accordance with the invention will be explained in the following with reference to FIG. 5. In the second embodiment, the weft thread is taken up and inserted into the shed by a rapier head 3 a which is provided at a rapier tape 3 b. Furthermore, at least one guide part or a guide structure 5 are provided at the rapier tape and/or rapier head which cooperate with guide elements 6.1-6.3 to guide the rapier tape and/or the rapier head in the shed, with the guide elements being offset inwardly by at least 10 cm or by at least 12 cm or by at least 16 cm with respect to the shed edge for the guidance of the guide part or of the guide structure. As the case may be, as shown in FIG. 5, the guide part or the corresponding guide structure can also be set back by at least 14 cm, at least 18 cm, at least 24 cm or at least 30 cm with respect to the rapier tip 3 in this embodiment.
The above description of the examples, embodiments and embodiment variants of the method in accordance with the invention usually makes reference to a bringer rapier. The described examples, embodiments and embodiment variants can naturally also be used in a corresponding manner and with the same advantages for a taker rapier.
The invention furthermore includes a rapier weaving machine having an apparatus 1 in accordance with one of the embodiment variants and embodiments described above and/or equipped to carry out a method in accordance with the above description.
In an advantageous embodiment variant, the rapier weaving machine includes a sley 9 with a reed 8 to beat on an inserted weft thread, with the start of the guidance of the guide part or of the guide structure 5 by the guide elements 6.1-6.i+1 not being before the time at which the sley has reached the rear rest position. In this respect, the start of the guidance of the guide part or of the guide structure by the guide elements can essentially coincide with the time at which the sley has reached the rear rest position. For the control of the apparatus for the insertion of a weft thread and in particular of the rapier movements and for the control of the sley movement, one or more control apparatus can be provided which control the rapier movements and the sley movement such, for example, that the start of the guidance of the guide part or of the guide structure by the guide elements essentially coincides with the time at which the sley has reached the rear rest position.
FIG. 6 shows a graphic representation of the rapier movement for an embodiment in accordance with the present invention. In this embodiment, the apparatus includes a bringer rapier and a taker rapier for the insertion of a weft thread and the rapier weaving machine includes a reed 8. In the graphic representation shown in FIG. 6, the path 13 of the bringer rapier tip 3 and the path 14 of the taker rapier tip 4 are drawn which travel the same in a full weaving cycle. In this respect, the paths covered are drawn in the direction of the abscissa and the machine angle in the direction of the ordinate. The width of the reed 8 is designated by the reference numeral 11. It normally corresponds to the width of the shed. A respective outer region is located at both sides of the reed 8 which has a width x which corresponds to the distance in the shed which the respective rapier travels in the apparatus in accordance with the invention until the respective guide part or the respective guide structure are guided by the guide elements.
In addition, three respective positions 3′, 3″, 3′″, 4′, 4″, 4′″ of the bringer rapier and of the taker rapier are drawn in the graphic illustration. Position 3′ shows the bringer rapier on the insertion of the weft thread; position 3″ shows the bringer rapier on the withdrawal after the transfer of the weft thread, and position 3′″ shows the bringer rapier outside the shed shortly before reaching the reversal point. Position 4′ shows the taker rapier on the advance in the shed; position 4″ shows the taker rapier after the takeover on the insertion of the weft thread; and position 4′″ shows the taker rapier outside the shed shortly before the reaching of the reversal point.
Two further graphic illustrations can be found in FIGS. 7A and 7B on the same sheet as FIG. 6. In this respect, FIG. 7A shows a graphic illustration of the sley movement for a conventional apparatus for the insertion of a weft thread and FIG. 7B shows a graphic illustration of the sley movement for an embodiment in accordance with the present invention. The graphic illustrations of the sley movement are arranged under the graphic illustration of the rapier movement shown in FIG. 6 such that the sley movements shown in FIGS. 7A and 7B run synchronously to the rapier movements shown in FIG. 6. This corresponds to the actual circumstances in a rapier weaving machine in which the rapier movements and the sley movements are controlled synchronously.
In the graphic illustration of the sley movement of a conventional apparatus for the insertion of a weft thread which is shown in FIG. 7 a, the sley is located in the rest position 9 a when the rapier tips have reached the outer edges of the reed or dip into the shed. The sley remains in the rest position during the weft insertion until the rapier tips have reached the outer edge of the reed on the withdrawal or leave the shed. From this time onward, the sley carries out a beating on movement to beat on the inserted weft thread by means of a reed which is provided at the sley. Only a comparatively small range of the machine angle is available for the sley movement from the rest position 9 a to the beating on position 9 b and back again which corresponds to the range during which the rapiers are located outside the shed in the conventional apparatus.
In the graphic illustration of the sley movement for an embodiment in accordance with the present invention, the sley is in the rest position 9 a when the rapier tips have traveled a specific distance x along the reed or have dipped correspondingly far into the shed. The sley remains in the rest position during the weft insertion until the rapier tips have reached the outer region of the reed on the withdrawal which corresponds to the distance x or have approached the shed edge up to the distance x. From this time onward, the sley carries out a beating on movement to beat on the inserted weft thread by means of a reed which is provided at the sley. A much larger range of the machine angle is available for the sley movement from the rest position 9 a to the beating on position 9 b and back again in comparison with the conventional apparatus, said range corresponding to the range during which the guide part and/or the guide structure is/are located outside the range of the guide elements in the embodiment, i.e. during which the guide part and/or the guide structure are not guided.
The longer machine angle range, which is available thanks to the apparatus in accordance with the invention and thanks to the method in accordance with the invention, allows the sley movement to be carried out less abruptly, whereby the bearings and the drive parts of the sley are spared or can be made lighter. The apparatus, the method and the rapier weaving machine of the above description combine the advantages of a guidance of the rapier tape and/or of the rapier head in the shed with the advantages of a saving sley movement.

Claims

1. An apparatus for the insertion of a weft thread (2) into a shed (10) of a rapier weaving machine, with the apparatus (1) including a rapier tape (3 b, 4 b) movable in the insertion direction, a rapier head (3 a, 4 a) at the same and at least one guide part or a guide structure (5) which are provided at the rapier tape and/or at the rapier head as well as a plurality of guide elements (6.1-6.i+1) which cooperate with the guide part or the guide structure to guide the rapier tape and/or the rapier head in the shed, characterized in that the start of the guidance of the guide part or of the guide structure by the guide elements is delayed until the rapier tip ( 3 , 4 ) is at a distance of at least 14 cm, in particular at a distance of at least 18 cm or of at least 24 cm, in the shed (10).

2. An apparatus in accordance with claim 1, including a rapier tape (3 b), a rapier head (3 a) and at least one guide part (5) or a guide structure (5) for a bringer rapier (3) and/or a rapier tape (4 b), a rapier head (4 a) and at least one guide part or a guide structure for a taker rapier (4), wherein the guide part associated with the bringer rapier or the corresponding guide structure is set back by at least 14 cm, in particular by at least 18 cm or at least 24 cm, with respect to the rapier tip ( 3 ), and/or wherein the guide part associated with the taker rapier or the corresponding guide structure is set back by at least 14 cm, in particular at least 18 cm, or at least 24 cm, with respect to the rapier tip ( 4 ).

3. An apparatus in accordance with claim 1, wherein the guide elements (6.1-6.i+1) for the guidance of the guide part or of the guide structure (5) are offset inwardly by at least 10 cm, are in particular offset inwardly by at least 12 cm or at least 16 cm, with respect to the shed edge.

4. An apparatus in accordance with claim 1, wherein a section is provided at or in the guide part or at or in the guide structure (5), in particular a trapezoidal section or a dovetail section, and wherein the guide elements (6.1-6 i+1) are made at least in part shape matched to the section of the guide part or of the guide structure to guide the rapier tape (3 b, 4 b) and/or the rapier head (3 a, 4 a) in the shed by means of the section and of the guide elements.

5. An apparatus in accordance with claim 1, wherein the start of the guidance of the guide part or of the guide structure (5) by the guide elements (6.1-6.i+1) is delayed at most for so long until the rapier tip ( 3 , 4 ) is at a distance of 50 cm, in particular at a distance of 40 cm or of 30 cm, in the shed.

6. A method for the insertion of a weft thread (2) into a shed (10) of a rapier weaving machine, in which

the weft thread (2) is taken up and inserted into the shed by a rapier head (3 a, 4 a) which is provided at a rapier tape (3 b, 4 b);

at least one guide part or a guide structure (5) are provided at the rapier tape and/or rapier head which cooperate with guide elements (6.1-6.i+1) to guide the rapier tape and/or the rapier head in the shed.

characterized in that

the guide part or the guide structure are only guided by the guide elements when the rapier tip ( 3 , 4 ) is moved into the shed by a distance of at least 14 cm, in particular at a distance of at least 18 cm or of at least 24 cm.

7. A method in accordance with claim 6, wherein the weaving machine includes a reed (8) which is provided at a sley (9) to beat on an inserted weft thread; and wherein the guide part or the guide structure (5) are only guided by the guide elements (6.1-6.i+1) when the sley is located in the rear rest position (9 a).

8. A method in accordance with claim 7, wherein the time at which the sley (9) reaches the rear rest position (9 a) essentially coincides with the start of the guidance of the guide part or of the guide structure by the guide elements.

9. A method in accordance with claim 6, wherein

the weft thread (2) is taken up and inserted into the shed by a rapier head (3 a) of a bringer rapier (3) which is provided at a rapier tape (3 b) and/or is taken over and conveyed onward by a rapier head (4 a) of a taker rapier (4) which is provided at a rapier tape (4 b);

in each case at least one guide part or a guide structure (5) are provided at the rapier tape and/or rapier head of the bringer rapier or of the taker rapier which cooperate with guide elements (6.1-6.i+1) to guide the respective rapier tape and/or the respective rapier head in the shed; and

wherein the guide part associated with the bringer rapier or the corresponding guide structure is set back by at least 14 cm, in particular by at least 18 cm or at least 24 cm, with respect to the rapier tip ( 3 ) of the bringer rapier, and/or wherein the guide part associated with the taker rapier or the corresponding guide structure is set back by at least 14 cm, in particular at least 18 cm or at least 24 cm, with respect to the rapier tip ( 4 ) of the taker rapier.

10. A method in accordance with claim 1, wherein the guide elements (6.1-6.i+1) are offset inwardly by at least 10 cm, are in particular offset inwardly by at least 12 cm or at least 16 cm, with respect to the shed edge for the guidance of the guide part or of the guide structure (5).

11. A method in accordance with claim 6, wherein a section is provided at or in the guide part or at or in the guide structure (5), in particular a trapezoidal section or a dovetail section, and wherein the guide elements (6.1-6 i+1) are made at least in part shape matched to the section of the guide part or of the guide structure to guide the rapier tape and/or the rapier head in the shed by means of the section and of the guide elements.

12. A method in accordance with claim 6, wherein the guide part or the guide structure (5) are guided by the guide elements (6.1-6.i+1) at the latest when the rapier tip ( 3 , 4 ) is at a distance of 50 cm, in particular at a distance of 40 cm or of 30 cm, in the shed.

13. (canceled)

14. A rapier weaving machine in accordance with claim 16, including a sley (9) with a reed (8) for the beating on of an inserted weft thread, wherein the start of the guidance of the guide part or of the guide structure (5) by the guide elements (6.1-6.i+1) is not before the time at which the sley has reached the rear rest position (9 a).

15. A rapier weaving machine in accordance with claim 14, wherein the start of the guidance of the guide part or of the guide structure by the guide elements essentially coincides with the time at which the sley has reached the rear rest position (9 a).

16. A rapier weaving machine comprising an apparatus for the insertion of a weft thread (2) into a shed (10) of the rapier weaving machine, the apparatus (1) including a rapier tape (3 b, 4 b) movable in the insertion direction, a rapier head (3 a, 4 a) at the same and at least one guide part or a guide structure (5) which are provided at the rapier tape and/or at the rapier head as well as a plurality of guide elements (6.1-6.i+1) which cooperate with the guide part or the guide structure to guide the rapier tape and/or the rapier head in the shed, characterized in that the start of the guidance of the guide part or of the guide structure by the guide elements is delayed until the rapier tip ( 3 , 4 ) is at a distance of at least 14 cm, in particular at a distance of at least 18 cm or of at least 24 cm, in the shed (10), the weaving machine inserting weft thread (2) into a shed (10) of a rapier weaving machine, in which

at least one guide part or a guide structure (5) are provided at the rapier tape and/or rapier head which cooperate with guide elements (6.1-6.i+1) to guide the rapier tape and/or the rapier head in the shed, and