Method for weaving a pile fabric on a rapier Axminster weaving machine, and a fabric woven according to this method

Abstract: This invention provides a method for weaving a pile fabric on a rapier Axminster weaving machine, whereby in the course of successive weft insertion cycles alternately one weft thread (1) alone and two weft threads (2), (3) one above the other are inserted between warp threads (4), (5), (6) so that a backing fabric (9) is woven, while pile threads (7) are so introduced that they are interlaced in the backing fabric (9) according to a three-shot weave by weft threads (1) inserted alone, which extend along the pile side of tension warp threads (6). According to this invention an Axminster pile fabric can be woven with pile formation according to a three-shot weave, while one pile row is formed per two weft insertion cycles. Also according to this invention an Axminster pile fabric is provided, in which in successive weft lines alternately one weft thread (1) alone and two weft threads (2), (3) one above the other are inwoven, and in which pile threads (7) are interlaced by weft threads (1) alone according to a three-shot weave.

Description: This invention relates to a method for weaving a pile fabric on a rapier Axminster weaving machine, whereby weft threads are brought between binding warp threads and tension warp threads so that a backing fabric is woven, while pile threads are so introduced that they are interlaced by weft threads according to a three-shot weave, so that each pile thread is passed round a weft thread as a pile burl with upright pile tufts, and while in the course of successive weft insertion cycles alternately one weft thread alone and two weft threads one above the other are inserted between the warp threads. This invention also relates to an Axminster pile fabric, in particular an Axminster carpet, comprising a backing fabric woven out of weft threads and warp threads, in which according to successive weft lines alternately one weft thread alone, respectively two weft threads running one above the other are inwoven, and in which pile threads are interlaced by weft threads according to a three-shot weave, so that each pile thread is passed round a weft thread as a pile burl with upright pile tufts. Rapier Axminster weaving machines comprise a shed-forming device and a weft insertion mechanism in order in the course of successive weft insertion cycles in each case to bring a weft thread into a shed formed between warp threads, so that a backing fabric is formed. This weft insertion mechanism can be provided with two weft insertion means in order in each operating cycle to be able to insert a respective weft thread at two different insertion levels. The weft threads can be inserted by means of rapiers, by means of a projectile or by a so-called needle insertion. With the latter method a weft thread is pushed double in loop shape through the shed by means of a long needle with an eye from one fabric side over the entire weaving width. On the other fabric side the weft loop is received by a bobbin which pulls an edging thread through the loop. Subsequently the needle returns to the former fabric side, while one tuft of the inserted loop slides into the eye of the needle. With each needle insertion a weft thread is therefore provided in the shed running back and forth over the width of the fabric. This weft thread is represented as two threads in fabric cross-sections. Since such a back and forth running weft thread has the same function as a weft thread which only extends from one fabric side to the other, and is also inserted by one and the same weft insertion means in one and the same weft insertion cycle, this must in the context of this patent application be considered as one weft thread. The term "weft thread" in this patent application, and in particular in the claims attached hereto, therefore refers both to a weft thread only extending from one fabric side to the other and to such a back and forth running weft thread. Furthermore rapier Axminster weaving machines are also provided with a series of upwardly and downwardly rotatable pile rapiers, and for each pile rapier a pile loader in which a number of different pile warp threads are provided. Each pile rapier can in an upwardly rotated position grip the extremity of one of the pile warp threads in its pile loader. In the course of its downward rotation the rapier pulls the pile warp thread out of the pile loader. Subsequently this is automatically cut through by a cutting device so that a well-defined length of the pile warp thread is taken along by the rapier. This piece of pile warp thread (called "pile thread" in that which follows) is in the course of the further downward rotation of the rapier brought to the edge of the fabric, and is so brought there in relation to the weft insertion path of a weft insertion means that it is interlaced in the backing fabric by the weft thread inserted thereafter by that weft insertion means. The pile threads are inwoven in the backing fabric as U-shaped pile burls, with upright pile tufts passed round a weft thread. Each pile loader can be brought by means of a jacquard device into a number of different positions, so that in each position the extremity of another pile warp thread comes into reach of the pile rapier working together therewith. In that manner pile can be formed with a great number of different colours (up to 12), while no dead pile warp threads have to be inwoven. This results in a particularly low pile yarn consumption. A weaving method exists, known by the name of "3-shot Corinthian", whereby on a rapier Axminster weaving machine in each weft insertion cycle one weft thread is inserted between warp threads, and whereby pile is formed according to a three-shot weave. According to this weaving method a backing fabric is formed in which next to each other alternately one weft thread and two weft threads one above the other are inwoven by binding warp threads. In this backing fabric tension warp threads extend between the weft threads inwoven one above the other and along the back of the weft threads inwoven alone. The pile threads are in each case interlaced by the top weft thread of the two weft threads inwoven one above the other. This weaving method produces pile burls with a good anchorage in the backing fabric and with good upright standing pile tufts. Furthermore the pile yarn consumption is minimal since the pile threads are not woven through to the back of the backing fabric. This weaving method however has the great disadvantage that there are three weft insertion cycles in order to form one pile burl row. The productivity of this weaving method is consequently not very high. This "3-shot Corinthian" weave have never been woven with double weft insertion because of the following list of reasons. From GB512962 an Axminster weaving machine is known which is provided for alternately inserting one and two weft threads, with which this weaving method could be applied with a high productivity. A number of other problems and disadvantages are however not solved with this. The required weaving machine has two weft insertion means with which in the course of the same weft insertion cycle two weft threads have to be inserted. The pile rapiers have to hold the pile threads between these two weft insertion paths during the double weft insertion without moreover impeding the movements of the weft insertion means. This is not possible with pile rapiers with the usual shape and dimensions. Another problem lies in the fact that, even were pile rapiers provided with limited dimensions of the pile rapier jaws, the weft insertion paths would still have to be placed rather far from each other in order that the pile rapier jaws would not impede the movement of the weft insertion means. This would mean that a rather large shed has to be formed between the warp threads. Because of this no high weaving speed would be able to be achieved. A problem could also further occur during the beating-up of the two weft threads located one above the other. During the beating-up these weft threads could be pulled against the pile rapier jaws by the binding warp threads. In the course of the beating-up the pile threads held by the pile rapier jaws could become caught between these two weft threads, with the result that they are torn out of the pile rapier jaws. In order to be able to weave fabrics with a rather short pile the points of the pile rapier jaws must furthermore be as close as possible to the holding fingers on the fabric edge. In the course of the beating-up of the two weft threads inserted one above the other the bottom weft thread could push the pile rapier jaws upwards, which could result in the formation of pile burls with pile tufts of unequal length - so-called J-burls. Weaving methods are known whereby pile burls are formed according to a two-shot weave and whereby one weft thread is inserted per cycle. According to these methods one pile burl row is therefore formed per two weft insertion cycles, but with the thus obtained fabrics the good pile anchorage is not achieved which is obtained with fabrics with pile formation according to a three-shot weave. The purpose of this invention is to provide a weaving method with the properties mentioned in the first paragraph of this specification, which can be implemented without any problem on the existing rapier Axminster weaving machines at high weaving speeds, and which produce fabrics with a proper pile formation according to a three-shot weave, but whereby one pile burl row can be formed per two weft insertion cycles. This purpose is according to this invention achieved because of the fact that with the weaving method described in the first paragraph of this specification, each pile thread is inwoven by a weft thread inserted alone, which extends along the pile side of the tension warp threads. In the course of the weft insertion cycles in which two weft threads are inserted one above the other the pile rapiers must not apply any pile threads to the fabric edge. The pile rapiers can therefore remain above the weft insertion paths. This means that these weft insertion paths can lie close to each other, so that the shed formed between the warp threads can be kept relative small. Because of this high weaving speeds can be achieved. In the course of the weft insertion cycles in which one weft thread is inserted alone the pile rapiers must provide pile threads in an inweaving position near to the fabric edge. Since only one weft thread is inserted the pile rapiers must moreover only leave one weft insertion path free. Because of this the pile rapier jaws can be implemented with a normal shape and dimensions. Since below the weft thread which interlaces the pile threads no second weft thread has to be beaten up, there is also no danger that the pile threads held by the pile rapiers are torn out of the pile rapiers in the course of the beating-up of this weft thread, or that the pile rapier jaws are pushed upwards in the course of the beating-up. The beating-up of the weft thread which interlaces the pile threads therefore occurs in exactly the same circumstances, and therefore equally without any problem, as with a weaving method whereby one weft thread is inserted per weft insertion cycle on a rapier Axminster weaving machine. Furthermore according to this method a fabric is obtained with good upright standing pile tufts and with a good anchorage of the pile burls in the backing fabric. Because of the fact that the weft threads inserted alone are inwoven in the backing fabric along the pile side of the tension warp threads, the pile yarn consumption is minimal. Furthermore the positions of the tension warp threads do not have to be altered in the course of the weaving. These can be kept between the two weft insertion paths. The tension warp weaving frame does not therefore have to be moved. The method according to this invention is preferably implemented on a weaving machine with two weft insertion means operating one above the other. In the course of the weft insertion cycles in which one weft thread is inserted alone, one of the two weft insertion means is then disengaged. It is moreover most preferable to allow the weft threads inserted alone in each case to be inserted by the weft insertion means operating at the top level, while the weft insertion means operating at the bottom level is disengaged. In the course of the weft insertion cycles in which one weft thread is inserted alone the pile rapiers can be in the weft insertion path of the disengaged bottom weft insertion means. Preferably sets of two binding warp threads are also provided so that these binding warp threads cross each other repeatedly and form successive openings between their crossings in which alternately a weft thread inserted alone and two weft threads inserted one above the other extend. Another object of this invention is an Axminster pile fabric, in particular an Axminster pile fabric manufactured according to the method according to this invention, with the characteristics mentioned in the second paragraph of this specification, of which each pile thread is interlaced by a weft thread inwoven alone. When weaving such a fabric one pile burl row can be woven per two weft insertion cycles, while for weaving the known 3-shot Axminster pile fabrics three weft insertion cycles were necessary in order to obtain one pile burl row. The fabric according to this invention can therefore be woven with a considerably higher productivity, and therefore with less production costs. Furthermore this fabric can be woven according to a weaving method which guarantees a problem-free operation of the Axminster weaving machine, and produces Axminster pile fabrics of a very good quality. Among others pile burls with a good anchorage in the backing fabric and with good upright standing pile tufts can be formed. The pile fabric according to this invention comprises, in a preferred embodiment, tension warp threads which extend in the backing fabric along the back of the weft threads inserted alone. Through the inweaving of the weft threads inserted alone along the pile side of the tension warp threads this fabric can be woven with a minimum pile yarn consumption. Each pile thread is preferably interlaced by a single weft thread which lies on the pile side of the tension warp threads and is followed by two weft threads located one above the other, of which one lies on the pile side of the fabric (between two pile rows) and one lies on the back of the fabric, and is not located below a pile row. Preferably this fabric also comprises sets of two binding warp threads which cross each other repeatedly and form successive openings between their crossings through which alternately one weft thread alone, respectively two weft threads located one above the other extend. According to a most preferred embodiment the Axminster pile fabric according to this invention is provided on the back with a synthetic material layer, in particular with a latex layer. Because of the fact that along the back of the single weft threads, no covering weft threads extend the pile-burl-forming pile threads are well accessible to the synthetic material, so that because of this an even better pile anchorage is achieved. In that which follows a more detailed specification is given of a possible weaving method according to this invention and of the pile fabric manufactured according to this method. This specification only serves to clarify the invention further, and to specify further properties and distinctive features thereof, and can therefore not be considered as a restriction on the protection claimed for this invention in the claims attached hereto. In this specification reference is made by means of reference numbers to the figures attached hereto, of which figure 1 is a schematic cross-section according to the warp direction of an Axminster pile fabric, in which it is indicated (by reference number 8) in which locations in the fabric no weft threads have been inserted as a result of disengaging a weft insertion means; and figure 2 represents the schematic cross-section from figure 1 without indication of the aforementioned locations where no weft threads have been inserted. The weaving method according to this invention is implemented utilising a rapier Axminster weaving machine with two weft insertion means operating one above the other. These means can be needles, rapiers or projectiles, which are provided in order in the course of the same weft insertion cycle simultaneously to insert a respective weft thread according to respective weft insertion paths located one above the other. The weaving machine is further also provided with a known shed-forming mechanism in order to form a shed between the warp threads (4), (5), (6) provided on the weaving machine. Prior to each weft insertion a shed is formed whereby the various warp threads are brought to the correct level in relation to the weft insertion paths in order to obtain the desired fabric. The weaving machine further also comprises a pile rapier mechanism with which cut-off pieces of pile thread (7) can be brought into an inweaving position near to the fabric edge. On the weaving machine several warp thread systems are provided, which each comprise two binding warp threads (4), (5) and one tension warp thread (6). The weft insertion mechanism is operated in order in successive weft insertion cycles alternately to allow only the top weft insertion means to operate, and subsequently to allow both weft insertion means to operate. Therefore alternately one weft thread (1) alone, and two weft threads (2), (3) one above the other are inserted. The locations where in the fabric no weft thread is inserted by disengaging the bottom weft insertion means have been indicated in figure 1 by reference number 8. In each warp thread system the tension warp thread (6) is in the course of the successive weft insertion cycles held between the two weft insertion paths. The two binding warp threads (4), (5) are prior to each double weft insertion brought respectively above and below the two weft insertion paths. Prior to each single weft insertion their positions are swapped, so that they form successive openings in which alternately one weft thread (1) and two weft threads (2), (3) one above the other are inwoven. The weft threads (1), (2), (3) and the warp threads (4), (5), (6) of the various warp thread systems in that manner-form a backing fabric (9) in which the weft threads (1) inserted alone are inwoven above the tension warp threads (6) and in which the weft threads (2), (3) inserted one above the other are inwoven respectively above and below the tension warp threads (6) by the binding warp threads (4), (5). Prior to each single weft insertion the pile rapiers bring pile threads (7) into an inweaving position near to the fabric edge. Because of the fact that the bottom weft insertion means is disengaged during this cycle the pile rapiers can be placed on the bottom weft insertion path. The pile threads (7) are passed as pile burls in U-shape round the weft threads (1) inserted alone. Pile burls are formed according to a three-shot weave, while one row of pile burls is formed per two weft insertion cycles. This weaving method enables pile fabrics of a good quality with a high productivity and with a low pile yarn consumption to be woven on rapier Axminster weaving machines with pile rapiers whose jaws can have a normal shape and dimensions.

Claims: Method for weaving a pile fabric on a rapier Axminster weaving machine, whereby weft threads are brought between binding warp threads (4), (5) and tension warp threads (6) so that a backing fabric (9) is woven, while pile threads (7) are so introduced that they are interlaced by weft threads according to a three-shot weave, so that each pile thread (7) is passed round a weft thread as a pile burl with upright pile tufts, and while in the course of successive weft insertion cycles alternately one weft thread (1) alone and two weft threads (2), (3) one above the other are inserted between the warp threads (4), (5), (6), characterised in that each pile thread (7) is inwoven by a weft thread (1) inserted alone which extends along the pile side of the tension warp threads (6). Method for weaving a pile fabric on a rapier Axminster weaving machine, according to claim 1, characterised in that the weaving machine comprises two weft insertion means operating one above the other and that in the course of the weft insertion cycles in which one weft thread (1) is inserted alone, one of the two weft insertion means is disengaged. Method for weaving a pile fabric on a rapier Axminster weaving machine, according to claim 2, characterised in that the weft threads inserted alone are in each case inserted by the weft insertion means operating at the top level, while the weft insertion means operating at the bottom level is disengaged. Method for weaving a pile fabric on a rapier Axminster weaving machine, according to any of the preceding claims characterised in that sets of two binding warp threads (4), (5) are so provided that they cross each other repeatedly and form successive openings between their crossings in which alternately a weft thread (1) inserted alone and two weft threads (2), (3) inserted one above the other extend. An Axminster pile fabric comprising a backing fabric (9) woven out of weft threads (1), (2), (3) and warp threads (4), (5), (6), in which according to successive weft lines alternately one weft thread (1) alone, respectively two weft threads (2), (3) running one above the other are inwoven, and in which pile threads (7) are interlaced by weft threads according to a three-shot weave, so that each pile thread is passed round a weft thread as a pile burl with upright pile tufts, characterised in that each pile thread (7) is interlaced by a weft thread (1) inserted alone. An Axminster pile fabric, according to claim 5 characterised in that the pile fabric comprises tension warp threads (6) which extend in the backing fabric (9) along the back of the weft threads (1) inserted alone. An Axminster pile fabric, according to claim 5 or 6 characterised in that it comprises sets of two binding warp threads (4), (5) which cross each other repeatedly and form successive openings between their crossings through which alternately one weft thread (1) alone, respectively two weft threads (2), (3) running one above the other extend. An Axminster pile fabric, according to claim 5, 6 or 7 characterised in that on the back it is provided with a synthetic material layer, in particular with a latex layer.

Inventors: DEBAES JOHNNY, DEWISPELAERE ANDRE, DEBAES, JOHNNY, DEWISPELAERE, ANDRE, Dewispelaere, André
Applicants: WIELE MICHEL VAN DE NV, N.V. MICHEL VAN DE WIELE
Application year: 2000
Main classification: D03D27
IPC codes: D03D27, D03D39