EP0534515B1

EP0534515B1 - Method for weaving face-to-face Jacquard pile fabrics

Info

Publication number: EP0534515B1
Application number: EP19920202605
Authority: EP
Inventors: Jan Vererfve
Original assignee: VERERFVE NV
Current assignee: VERERFVE NV
Priority date: 1991-08-28
Filing date: 1992-08-27
Publication date: 1997-05-21
Anticipated expiration: 2012-08-27
Also published as: DE69219845T2; EG19466A; EP0534515A1; TR26645A; DE69219845D1; BE1005208A4

Description

The invention relates to an improved method for weaving face-to-face Jacquard pile fabrics. With the manufacture of such fabrics according to the generally known method (as described in BE-896.102), a backing fabric is woven by weaving weft ends and warp ends on two levels one above the other. The warp ends of this backing fabric consist of tight warp ends and loose warp ends. Pile ends are woven into these backing fabrics at the same time. By allowing pile ends to transfer from the upper backing fabric to the lower backing fabric, or the other way around, the pile of the fabrics is formed. Afterwards the face-to-face is separated into its two parts, by cutting through the pile ends which run between both backing fabrics. These two fabrics are called the upper fabric and the lower fabric. The back of the upper fabric is formed by the top of the upper backing fabric, the back of the lower fabric by the underside of the lower backing fabric. The pile side of both fabrics is formed on the side directed towards each other of the upper and the lower backing fabric.
With every weft there is the choice for every pile end of allowing it to run either from the upper fabric to the lower fabric and/or the other way around, and consequently to form pile, or of allowing this pile end to remain parallel to one of the backing fabrics. This choice is essentially determined by the pattern which is desired to be formed in the fabrics. A specific pile end is allowed to form pile if the color of that pile end is needed for the pattern. Another pile end, of which the color has already been used earlier and/or will be further needed and is not needed in a specific place in the pattern, is allowed to run preferably invisibly on the pile side, parallel to the upper or lower backing fabric. A combination of a weft in the lower fabric and a weft in the upper fabric, whereby, pile is formed by a pile end, is called a pile point. A pile point thus consists - in total for the face-to-face - of two wefts, or 1 weft per fabric. The pile forming pile ends are called active pile ends or active pile. The other pile ends, which at a specific place do not participate in forming the pattern, are then called the dead pile ends or dead pile.
The dead pile ends can be woven into the backing fabrics or not. If the dead pile is not woven-in during weaving this remains on the underside of the lower backing fabric or on the top of the upper backing fabric, and is later removed. When the dead pile ends are however woven-in it will of course be attempted to weave these in (on to pile side) as invisibly as possible. It is a known method to solve this problem by weaving-in the dead pile ends, forming a smooth surface with the tight warp ends. Moreover these dead pile ends are proportionally distributed or otherwise between the upper piece and the lower piece.
The appearance of the back of each fabric can also play a role with the choice of the manner in which, and in which fabric a dead pile end is woven-in.
By means of a jacquard device the position of the possibly different pile ends in each of the fabrics is determined with each weft, in function of the desired pattern, (by allowing certain pile ends to form pile with certain wefts and other pile ends not), in function of the choice of whether to weave-in the pile ends or not, and in function of the desired weave.
Such jacquard devices essentially consist of positioning means for the various pile ends, a control device for these positioning means, and a data processing device which can pass on the input data with each weft and for each pile end to the aforementioned control device. Such a data processing device can operate mechanically, electronically or electromechanically, or can be a computer. The desired characteristics of the fabric and of the pattern are translated into data, which are put into such a device, are processed, and are finally passed on via the control device to the positioning means and are converted into pile end positions. The aforementioned data are placed on suitable data carriers for their input into the data processing device. With the use of a computer the processing of the data is possibly effected with the assistance of suitable software.
The problem which lies at the basis of the invention, is explained in that which follows, and is illustrated on the basis of figures 1, 2 and 3a, and 3b.
We consider a face-to-face fabric with a background weave which has a repeat of 4 picks (see fig.1):

A weft (1) in the lower fabric, above the lower tight warp end (5).
A weft (2) in the upper fabric, above the upper tight warp end (6).
A weft (3) in the lower fabric, under the lower tight warp end (5).
A weft (4) in the upper fabric, under the upper tight warp end (6).

Thereafter again comes a weft (1), etc... whereby the cycle is repeated.
The successive wefts can possibly also occur in reverse succession ( wefts (4), (3), (2), (1) ), or the succession can be shifted for example consecutive wefts (3), (4), (2), (1). Such variants can finally all be repeated up to the first mentioned background weave, shown in figure 1.
The effect of the loose warp ends (7) and (8) is of secondary importance and will not be discussed in this description, and no longer be indicated in the following figures (as from figure 2), for the sake of the clarity of the figures. The dead pile ends are woven-in, running parallel to one of the tight warp ends (5) or (6).
Because of the fact that the weave has a repeat of 4 picks (see fig. 2), a color change (transition from a pile end (9) or (10) of active pile to dead pile, and from another pile end (10) or (9) of dead pile to active pile), is in general - because of reasons which are further clarified - performed after at least 4 picks. This means that a certain color in the pattern of the fabric, is at least maintained over 4 picks, or put differently, remains over two pile points. The smallest detail in the pattern in each of the fabrics formed therefore has a dimension (a), which corresponds to two pile points.
For fabrics with a high weft density this forms an insignificant disadvantage, but for fabrics with a low weft density, for example 4 picks per cm. per fabric, this will result in a course design formation, since the design can only be changed every two pile points. The smallest detail in the pattern of such a fabric will therefore at least have the dimension of 1/2 cm.
If this disadvantage is to be remedied by nevertheless providing the possibility of changing the design with every pile point, then it must be taken into account that this will involve a number of undesired effects, which are very inconvenient, both for the appearance of the pile side, and of the back of the fabrics. In figures 3a and 3b these undesired effects are illustrated on the basis of an example.
We consider (see fig. 3a and fig. 3b) again a face-to-face pile fabric with a background weave with a repeat of 4 picks, with wefts (11), (13), (15), (17) and (19), and tight warp end (21) in the lower fabric and wefts (12), (14), (16), (18) and (20) and tight warp end (22) in the upper fabric. A pile end (23) is initially dead pile, and is woven into the upper fabric, running parallel to tight warp end (22). After weft (16) - a weft which does not form the end of a repeat (a) - pile end (23) must start to form pile. Another pile end (24), which is initially active pile must after that same weft (16) become dead pile. The result becomes clear in figure 3a: Pile end (23) is woven into the upper fabric the time before by the weft (14), and is woven into the lower fabric the first time by weft (17). Pile end (24) is the time before woven into the upper fabric by weft (16), and the first time in the lower fabric, by weft (19). When the upper fabric and the lower fabric are separated from each other by cutting through the pile ends (23), (24) which extend between both fabrics pile end (23) will be visible between weft (14) and (16) in the upper fabric on the pile side between two pile points - wefts (14) and (16) - where pile end (24) has formed pile. Consequently an undesired mixing of the colors of pile ends (23) and (24) is obtained. The same occurs in the lower fabric between weft ends (17) and (19). Pile end (24) is visible there on the pile side between two pile points - wefts (17) and (19) - where pile end (23) has formed pile. Here too between the tufts of a pile end (23) with the desired color, a tuft of a pile end (24) with another color becomes visible on the pile side. Since the formation of a sharply defined pattern is one of the objectives with jacquard weaving such an effect is highly undesirable.
In other examples of the transition of the pattern or design (transition from active pile to dead pile of a pile end, and the other way around) effects also develop which are detrimental to the good appearance of the back of the fabric. It can after all also be an objective to make the woven pattern as truly visible as possible on the back of the fabric.
Such an example is shown in figure 3b. The background weave again has a repeat over 4 picks (31), (32), (33), (34). The pile end (40) initially forms pile. After the second weft (32) this pile end (40) is to change over from active pile to dead pile, woven into the upper fabric, and this pile end (40) is again to form pile on the seventh weft (37). This pile end (40) will be above the fourth weft (34) and thereafter extend toward the lower fabric in order to be woven-in under the seventh weft (37) and further to form pile with the wefts (38), and the following ones. The undesired effect consists in that, on the back of the upper fabric, at the location of weft (34), pile end (40) is visible, while this forms no pile there (not included in the figure). This is to be avoided because the appearance of the back in this manner no longer corresponds to the pattern formed on the pile side.
This invention more particularly relates to an improved method for weaving face-to-face Jacquard pile fabrics with woven-in pile ends and with a background weave which has a repeat of 4 picks.
The invention is intended to provide such a method with which it becomes possible to have the pattern of the pile fabrics change with every pile point, while the undesired effects - when changing the effect of a pile end with certain wefts of the repeat - on the back and/or on the pile side of the fabrics, are avoided.
The purpose of the invention is more specifically to provide a method for weaving such face-to-face fabrics, through which it becomes possible to form patterns with a minimum detail of one pile point, without undesired effects on the pile side and/or the back of the fabrics.
This is achieved by a method which results in a first series of transitional weaves, which, when they are applied with the changing of the effect of a pile end when weaving a face-to-face jacquard pile fabric with woven-in pile ends and a background weave with a repeat of 4 picks, every possible transition which, according to the known method could give a detrimental effect on the pile side of at least one of the fabrics, avoids this detrimental effect and if possible avoids the possible detrimental effects on the back of the fabrics, and results in a second series of transitional weaves which, when they are applied with the changing of the effect of a pile end when weaving a face-to-face jacquard pile fabric with woven-in pile ends and a background weave with a repeat of 4 picks, every possible transition which, according to the known method could give a detrimental effect on the back of at least one of the fabrics, avoids this detrimental effect, and if possible also avoids the possible detrimental effects on the pile side of the fabrics.
Another object of the invention consists of pile fabrics which are woven according to one of the methods according to the invention.
By tending to detrimental effects for the pile side, detrimental effects can arise for the back, and the other way around. In some cases a choice must be made, since solving the detrimental effects on pile side and back at the same time is impossible in certain cases. The choice which is made depends on the importance that is attached to the pile side, respectively the back of the fabric.
The method according to the invention therefore consists of two series of transitional weaves.
The purpose of the first series of transitional weaves consists of avoiding the detrimental effects with certain transitions which produce these detrimental effects, whereby - if it is impossible to avoid the detrimental effects on the pile side and the back at the same time - preference is given to the elimination of the detrimental effects on the pile side.
The purpose of the second series of transitional weaves is identical to that of the first series, with the difference that if a choice must be made here preference is given to the elimination of the detrimental effects on the back.
The method according to the invention is characterized in that to begin with, all possible situations are considered for the effect of a pile end, in a cycle of 4 wefts. For the simplification of the description, a status code is given to each of these situations. The various possible situations with their respective status code are the following:

Pile forming over the whole cycle: status code O
Pile forming over the first part of the cycle (the first two wefts) and over the second part of the cycle (the last two wefts) woven into the lower fabric: status code 1(O)
Pile forming over the first part of the cycle (the first two wefts) and over the second part of the cycle (the last two wefts) woven into the upper fabric: status code 1(B)
Pile forming over the second part of the cycle (the last two wefts) and over the first part of the cycle (the first two wefts) woven into the lower fabric: status code 2(O)
Pile forming over the second part of the cycle (the last two wefts) and over the first part of the cycle (the first two wefts) woven into the upper fabric: status code 2(B)
Woven into the lower fabric over the whole cycle: status code 3
Woven into the upper fabric over the whole cycle: status code 4

The method according to the invention, is characterized in that those transitions between two of the above mentioned situations, where a detrimental effect occurs, a changed weave for the pile end is prescribed.
This changed weave is the same for the first series of transitional weaves (preference for good pile side) as for the second series of transitional weaves (preference for good back), in the cases where the detrimental effects on the pile side and on the back can be avoided at the same time for that same changed weave. When this is not the case then the changed weave for a same transition differs, depending on whether it belongs to the first or to the second series of transitional weaves.
These changed weaves, can in fact be considered as changes in the course of the considered pile end at the location of one or two wefts, belonging to the second half of the first cycle, belonging to the first half of the second cycle of 4 wefts. In that which follows these changes are indicated with the name: "actions".
The number of actions which makes it possible to solve all possible detrimental effects, is limited to 6. In each case it concerns the transition between two cycles of 4 wefts, respectively called the first and the second cycle.
The actions are indicated by so-called action codes, and are the following:

action 1: A pile end which runs above the third weft (lower fabric) of the first cycle and under the first weft (lower fabric) of the second cycle, is lowered under the 3rd weft of the first cycle, and raised above the first weft of the second cycle.
action 2: A pile end which runs above and the 4th weft (upper fabric) of the first cycle, is lowered under this 4th weft.
action 3: A pile end which runs above the third weft (lower fabric) of the first cycle, is pulled under this third weft.
action 4: A pile end which runs, under the second weft (upper fabric) of the second cycle is pulled above the second weft of the second cycle.
action 5: A pile end which runs under the first weft (lower fabric) of the second cycle, is raised above this first weft.
action 6: A pile end which runs above the 4th weft (upper fabric) of the first cycle, and runs under the second weft (upper fabric) of the second cycle, is lowered under the 4th weft of the first cycle and raised above the second weft of the second cycle.

The first two wefts of each cycle are above the respective warp ends in both fabrics, the last two wefts under these warp ends. The prescribed actions only relate to the last two wefts of the first (old) cycle and to the first two wefts of the second (new) cycle. The first half of the first cycle and the second half of the second cycle are after all part of other transitions, respectively between the cycle which precedes the aforementioned first cycle and that first cycle and between the second cycle and the cycle which follows it.
The method according to the invention is further characterized in that the first series of changed weaves prescribe, for each possible transition between cycles of 4 wefts in which according to the known method a detrimental effect occurs on the pile side of at least one of the fabrics, a specific "action" which solves at least that detrimental effect on the pile side, and that the second series of changed weaves prescribe, for each transition in which according to the known method a detrimental effect occurs on the back of at least one of the fabrics, a specific "action", which solves at least that detrimental effect on the back.
For the following transitions, (indicated by their status codes) the following actions (indicated by their action codes) are undertaken (respectively by the first and the second series of changed weaves) :
By the first series of changed weaves (preference for good pile side) see fig. 7

transition from 0 to 2 (B): action 4
transition from 1 (O) to 0: action 3
transition from 1(O) to 1(O) or (1B): action 3
transition from 1(O) to 2 (O): action 1
transition from 1(O) to 3: action 1
transition from 1(B) to 2(B): action 6
transition from 1(B) to 4: action 2
transition from 2(O) or 2(B) to 2(B): action 4
transition from 3 to 2(O): action 5
transition from 4 to 2(B): action 6

By the second series of changed weaves (preference for good back) see fig. 8

transition from 0 to 2(O): action 5
transition from 1(O) to 2(O): action 1
transition from 1(O) to 3: action 1
transition from 1(B) to 0: action 2
transition from 1(B) to 1(O) or 1 (B): action 2
transition from 1(B) to 2(B): action 6
transition from 1(B) to 4: action 2
transition from 2(O) or 2(B) to 2(O): action 5
transition from 3 to 2(O): action 5
transition from 4 to 2(B): action 6

When the positions of the pile end, successively in relation to the 3rd and the 4th weft of the first cycle and the first and the second weft of the second cycle, are indicated by letters B (above) or O (under), the changed weaves of the first series provide the following changes :

transition from 0 to 2(B): O-B-B-O becomes O-B-B-B
transition from 1(O) to O: B-O-O-B becomes O-O-O-B
transition from 1(O) to 1(O) or 1(B): B-O-O-B becomes O-O-O-B
transition from 1(O) to 2(O): B-O-O-O becomes O-O-B-O
transition from 1(O) to 3: B-O-O-B becomes O-O-B-B
transition from 1(B) to 2(B) : B-B-B-O becomes B-O-B-B
transition from 1(B) to 4: B-B-B-O becomes B-O-B-O
transition from 2(O) or 2(B) to 2(B): O-B-B-O becomes O-B-B-B
transition from 3 to 2(O): B-O-O-O becomes B-O-B-O
transition from 4 to 2(B): B-B-B-O becomes B-O-B-B

transition from O to 2(O): B-O-O-O becomes B-O-B-O
transition from 1(O) to 2(O): B-O-O-O becomes O-O-B-O
transition from 1(O) to 3: B-O-O-O becomes O-O-B-O
transition from 1(B) to 0: B-B-B-O becomes B-O-B-O
transition from 1(B) to 1(O) or 1(B): B-B-B-O becomes B-O-B-O
transition from 1(B) to 2(B) : B-B-B-O becomes B-O-B-B
transition from 1(B) to 4: B-B-B-O becomes B-O-B-O
transition from 2(O) or 2(B) to 2(O): B-O-O-O becomes B-O-B-O
transition from 3 to 2(O):B-O-O-O becomes B-O-B-O.
transition from 4 to 2(B):B-B-B-O becomes B-O-B-B.

Further characteristics and advantages of the method according to the invention and of the face-to-face fabrics manufactured according to this method, are clarified on the basis of the following detailed description of the possible transitions - after a pile point which is not the end of a repeat - in the effect of a pile end with a background weave with a repeat of 4 picks with woven-in dead pile ends, whereby per transition which produces a detrimental effect the action is discussed which according to this method is undertaken, in order to eliminate this detrimental effect on the pile side and/or on the back. This description of the method, according to the invention, does however not limit the application of this method to face-to-face fabrics with a background weave with a repeat of 4 picks, of which the wefts have the sequence adopted in this description and represented in the figures.
This description is illustrated on the basis of the figures attached hereto, whereby:

figure 1 is the longitudinal cross-section of a face-to-face pile fabric, with woven-in dead pile, whereby pile is formed with each weft.
Figure 2 is the longitudinal cross-section of a face-to-face pile fabric, with woven-in dead pile, whereby pile is formed with each weft, and whereby the minimum detail amounts to 4 picks or 2 pile points.
Figure 3a is the longitudinal cross-section of a face-to-face pile fabric, with woven-in dead pile, whereby pile is formed with each weft, and whereby the minimum detail amounts to only 2 picks or 1 pile point, and whereby the undesired effects are visible on the pile side.
Figure 3b is the longitudinal cross-section of a face-to-face pile fabric, with woven-in dead pile, whereby pile is formed with each weft, and whereby the minimum detail amounts to only 2 picks or 1 pile point, and whereby the undesired effects are visible on the back.

Figures 4a up to and including 4y are longitudinal cross-sections of a face-to-face fabric with woven-in dead pile, over two cycles of 4 wefts whereby the possible and significant transitions in the effect of a pile end are indicated in the various figures - after a pile point which does not form the end of a repeat - according to the known method (dashed line), and according to the method according to the invention (full lines) whereby preference is given to the elimination of the detrimental effects on the pile side of the fabrics.
Figures 5a up to and including 5y are longitudinal cross-sections of a face-to-face fabric with woven-in dead pile, over two cycles of 4 wefts whereby the possible and significant transitions in the effect of a pile end are indicated in the various figures - after a pile point which does not form the end of a repeat - according to the known method (dashed line), and according to the method according to the invention (full lines) whereby preference is given to the elimination of the detrimental effects on the back of the fabrics.
More specifically figures 4a up to an including 4y, respectively figures 5a up to and including 5y show the transitions between situations for the pile end with the following status codes:

Figs 4a and 5a: : 1(O) - 0
Figs 4b and 5b: : 1(B) - 0
Figs 4c and 5c: : 1(O) - 3
Figs 4d and 5d: : 1(B) - 4
Figs 4e and 5e: : 1(O) - 1(O) or 1(B)
Figs 4f and 5f: : 1(B) - 1(O) or 1(B)
Figs 4g and 5g: : 1(O) - 2(O)
Figs 4h and 5h: : 1(B) - 2(B)
Figs 4i and 5i: : 0 - 3
Figs 4j and 5j: : 0 - 4
Figs 4k and 5k: : 0 - 1(O) or 1(B)
Figs 4l and 5l: : 0 - 2(O)
Figs 4m and 5m: : 0 - 2(B)
Figs 4n and 5n: : 2(O) or 2(B) - 0
Figs 4o and 5o: : 2(O) or 2(B) - 3
Figs 4p and 5p: : 2(O) or 2(B) - 4
Figs 4q and 5q: : 2(O) or 2(B) - 1(O) or 1(B)
Figs 4r and 5r: : 2(O) or 2(B) - 2(O)
Figs 4s and 5s: : 2(O) or 2(B) - 2(B)
Figs 4t and 5t: : 3 - 0
Figs 4u and 5u: : 3 - 1(O) or 1(B)
Figs 4v and 5v: : 3 - 2(O)
Figs 4w and 5w: : 4 - 0
Figs 4x and 5x: : 4 - 1(O) or 1(B)
Figs 4y and 5y: : 4 - 2(B)

Figure 6 is a table in which, for each transition from a first situation (I) to a second situation (II), the letter of the figure (from figures 4a up to and including 4y and 5a up to and including 5y) which illustrates this transition, is indicated in the box at the intersection of the respective column and row.
Figure 7 is a table, in which for the transitional weaves with preference for a good pile side the actions (indicated by their codes) provided according to the method according to the invention can be read off in function of the situation of a pile end in a first cycle of 4 picks (indicated by the status codes) and the following situation of that pile end in a second cycle (II) of 4 picks (indicated by means of status codes). The situation of the pile end in the first cycle is read off in the columns, the situation of the pile end in the second cycle in the rows.
Figure 8 is a table, in which for the transitional weaves with preference for a good back the actions (indicated by their action codes) provided according to the method according to the invention can be read off in function of the situation of a pile end in a first cycle of 4 picks (indicated by the status codes) and the following situation of that pile end in a second cycle (II) of 4 picks (indicated by means of status codes). The situation of the pile end in the first cycle (I) is read off in the columns, the situation of the pile end in the second cycle (II) in the rows.
The method according to the invention is characterized in that in a first step all possible transitions in the effect of a specific pile end, which do not take place after one repeat of 4 picks, are considered as the transition between two cycles of 4 picks, whereby the pile end in each of these cycles has a well defined effect.
The number of possible situations is seven and is indicated by the status codes as described above: 0, 1(O), 1(B), 2(O), 2(B), 3, and 4.
In theory there should therefore be 49 possible transitions. There are however a number of transitions which never occur or several cases which amount to one same case (see figs. 7 and 8). Since the wefts which are important for the action are the last two of the first cycle and the first two of the second cycle, it makes no difference to the action whether the pile end is in the first cycle in the situation 2(O) or 2(B), or whether it is in the second cycle in the situation 1(O) or 1(B).
The situations 2(O) or 2(B) for the first cycle (I) and 1(O) or 1(B) for the second cycle (II) are consequently entered in one column, respectively one row. Of the remaining 36 possibilities (6 rows and 6 columns) the following transitions are unimportant because they are in fact not transitions or because the transition is meaningless.

O-O, 3-3 and 4-4:: The pile end maintains the same action: no transition.
3-4 and 4-3 :: transition from weaving-in in lower fabric to weaving-in in upper fabric without pile forming, or the other way around is meaningless.
3 - 2(B) :: transition from weaving-in in lower fabric to pile forming via weaving-in in upper fabric is meaningless, the transition 3 - 2(0) then occurs.
4 - 2(O) :: transition from weaving-in in upper fabric to pile forming via weaving-in in lower fabric is meaningless; the transition 4 - 2(B) then occurs.
1(B) - 3 :: transition from pile forming to weaving-in in lower fabric via weaving-in in upper fabric is meaningless; the transition 1(B) - 4 then occurs.
1(O) - 4 :: transition from pile forming to weaving-in in upper fabric via weaving-in in lower fabric is meaningless; the transition 1(0) - 3 then occurs.
1(O) - 2(B) :: transition from pile forming to pile forming via first weaving-in in lower fabric and then weaving-in in upper fabric is meaningless; the transition 1(O) - 2(O) or 1(B) - 2(B) then occurs.
1(B) - 2(O) :: transition from pile forming to pile forming via first weaving-in in upper fabric and then weaving-in in lower fabric is meaningless; the transition 1(B) - 2(B) or 1(O) - 2(O) then occurs.

In the tables from figures 7 and 8 the boxes which correspond to the above mentioned transitions have been crossed through.
For the remaining 25 cases - in case an action has to be undertaken - the respective action codes are indicated, or - if no action has to be undertaken - the box is left blank.
Each of these cases is also represented in figures 4a up to and including 4y and 5a up to and including 5y, and is described in the following with regard to the known method, and the disadvantages thereof, as well as with regard to the method according to the invention by carrying out an action which eliminates these disadvantages, either with preference for a good pile side, (figs. 4a up to and including 4y and fig. 7), or with preference for the good back (figs. 5a up to and including 5y and fig. 8). The first weft (41) of the first cycle is above the tight warp end (49) in the lower fabric, the second weft end (42) of the first cycle above the tight warp end (50) in the upper fabric, the third weft end (43) of the first cycle under the tight warp end (49) in the lower fabric, the fourth weft end (44) of the first cycle under the tight warp end (50) in the lower fabric. This position of the weft ends (45), (46), (47) and (48) in relation to the tight warp ends (49) and (50) in the lower fabric, respectively in the upper fabric, is repeated in the second cycle.
With regard to the transitional weaves according to the method, according to the invention, whereby the elimination of the detrimental effects on the pile side has priority, in figures 4a up to and including 4y the background weave of a face-to-face fabric with woven-in dead pile over two cycles of 4 picks is each time represented in cross-section (background weave with repeat of 4 picks).
In figure 4a the pile end (51) is in the situation with status code 1(O) in the first cycle and in the situation with code O in the second cycle. With the known method (dashed line) this will result in a mixing effect at the location of weft (45). The solution consists of the application of action 3, whereby the pile end (51) is pulled under the weft end (43).
In figure 4b - transition from 1(B) to O - no detrimental effect occurs on the pile side. On the back a detrimental effect does however occur, - pile end (51) visible on the back at the location of weft (44) where no pile is formed - but this cannot be solved without causing a detrimental effect on the pile side. Since in this series of transitional weaves the preference is given to a good pile side, as a result no action at all is undertaken. The same is valid for the cases represented in figures 4f, 4i, 4j, 4k, 4l, 4n, 4o, 4p, 4q, 4r, 4t, 4u, 4w and 4x.
In figure 4c the pile end (51) changes from situation 1(O) to situation 3. Action 1 is undertaken, according to the method according to the invention in order to eliminate the mixing effect at the location of weft (45) on the pile side.
In figure 4d with the transition from situation 1(B) to situation O no detrimental effect occurs on the pile side, but a detrimental effect on the back at the location of weft (44) can be eliminated by action 2, without damaging the pile side.
In figure 4e with the transition from situation 1(O) to situation 1(O) or 1(B) according to the known method a mixing effect again occurs on the pile side, through the application of action 3 this problem is solved.
With the transition from the situation 1(O) to 2(O), represented in figures 4g, with the method according to the invention, at the location of the weft (45) a mixing effect occurs. By the method according to the invention this is solved by action 1, whereby the pile end (51) is lowered under weft (43) and raised above weft (45).
In figure 4h for the transition from situation 1(B) to situation 2(B) according to the known method with weft (44) a mixing effect occurs, which according to the invention is rectified by action 6.
In figure 4m - transition from situation O to situation 2(B) - mixing effects are again rectified on the pile side through application of action 4.
In figures 4s, and 4y actions 4, and 6 according to the invention respectively take care of the elimination of detrimental effects on the pile side, which according to the known method arise with the transitions represented, respectively 2(O) or 2(B) to 2(B), and 4 to 3(B), here each time mixing effects are also rectified.
In the case of figure 4v - transition from situation 3 to 2(O) no detrimental effect at all occurs on the pile side. Through the application of action 5 a detrimental effect on the back (at the location of weft (45)) can however be eliminated.
From what precedes it therefore appears that there are 8 transitions where the method according to the invention is applied in order to rectify detrimental effects, on the pile side - by the formation of so-called bridges on the back - and 2 transitions where the method according to the invention is applied in order to improve the back, without the pile side suffering damage. These 10 transitional weaves according to the invention which develop through the - per case - application of the respectively prescribed actions, according to the invention, therefore form the first series of transitional weaves, which are used if the good quality of the pile side is set as priority.
To illustrate the transitional weaves according to the method according to the invention, whereby the elimination of detrimental effects on the back has priority, the various transitions of a pile end (51) in the same face-to-face fabric are represented in figures 5a up to and including 5y, in the same manner as for figures 4a up to and including 4y. The cross-sections of the face-to-face fabric represented are also identical.
The objective of the actions according to the invention is in each case to avoid a pile forming pile end (51) from being visible on the back, and to avoid a dead pile end (51) from being visible on the back.
In the figures 5a, 5i, 5j, 5k, 5l, 5m, 5n, 5o, 5p, 5q, 5s, 5t, 5u, 5w and 5x no detrimental effects occur on the back with the respective transitions.
With the transition from situation 1(B) to O, from figure 5b, according to the known method pile end (51) is visible on the back of the upper fabric, at the location of weft (44), while this pile end (51) forms no pile there. This undesired effect is rectified through application of action 2, according to the invention.
In figure 5c - transition from situation 1(O) to 3 - pile end (51) according to the known method is not visible on the back of the lower fabric at the location of weft (43) - where it forms pile - and is visible at the location of weft (45) - where it does not form pile. Action 1 according to the invention rectifies this detrimental effect.
In figure 5d - transition from situation 1(B) to 4 - pile end (51) according to the known method is visible on the back of the upper fabric at the location of weft (44), where it does not form pile. The problem is solved through application of action 2 according to the invention.
In figure 5f - transition from situation 1(B) to 1(O) or 1(B) - pile end (51) according to the known method is visible on the back of the upper fabric, at the location of weft (44), where it does not form pile. The detrimental effect on the back is rectified through application of action 2, according to the invention.
In figure 5g - transition from situation 1(O) to 2(O) - pile end (51) according to the known method is not visible on the back of the lower fabric, at the location of weft (43) - where pile is formed, and is visible on the back of the lower fabric, at the location of weft (45) - where no pile is formed. This disadvantage is rectified through application of action 1, according to the invention.
In figure 5h - transition from situation 1(B) to 2(B) - pile end (51) according to the known method is visible on the back of the upper fabric, at the location of weft (44) - where no pile is formed, and not visible on the back of the upper fabric, at the location of weft (46) - where pile is formed. This detrimental effect is rectified through application of action 6, according to the invention.
In figure 51 - transition from situation O to 2(O) - the pile end (51) at the location of weft end (45) is visible on the back of the lower fabric, where no pile is formed. Action 5, according to the invention remedies this disadvantage.
In figure 5r - transition from situation 2(O) or 2(B) to 2(O) - pile end (51) according to the known method is visible on the back of the lower fabric, where pile is no longer formed. Action 5, according to the invention remedies this disadvantage.
In figure 5v - transition from situation 3 to 2(O) - pile end (51) according to the known method is visible on the back of the lower fabric at the location of weft (45), where it forms no pile. Action 5, according to the invention rectifies this detrimental effect.
In figure 5y - transition from situation 4 to 2(B) - pile end (51) according to the known method, is visible on the back of the upper fabric at the location of weft (44), - where no pile is formed - and not visible on the back of the upper fabric at the location of weft (46), where pile is formed. The solution to this problem is achieved through application of action 6, according to the invention.
From what precedes it therefore appears that in ten cases the back can be improved through application of the method, according to the invention. This series of transitional weaves is applied in the manufacture of fabrics, where a good quality of the back has priority. (Since the improvement of the back in some cases results in a detrimental effect for the pile side).
The method according to the invention can in practice be applied through effect on the jacquard device which determines the positions of the pile ends in the fabrics. More specifically, with use of a computer as data processing device of the jacquard device, a software program can be developed which adapts the input data for the positions of the pile ends, when a transition occurs, which could give rise to a detrimental effect. The various possible situations and the various transitions, are then also read into the computer.
To begin with the possibility of choice is provided by the program between a good pile side and a good back, as priority requirement. Subsequently a specific action is associated (tables 7 and 8) for each of those two possibilities, with each of the transitions to be adapted between two situations. On the basis of the successive situations known by the computer, with each transition, which requires an adaptation, the instructions for the control device which were determined on the basis of the original input data, are adapted and transformed via the control device and positioning means of the jacquard device into transitional weaves in the fabrics prescribed according to the invention.
The advantage of the method according to the invention lies in the fact that in the face-to-face fabrics considered here the transition of a specific pile end, from one situation to another for its effect in the fabrics, can be allowed to occur with whatever pile point, and moreover it can be avoided that detrimental effects occur either on the back of the fabrics, or on the pile side thereof, (or on both sides of the fabrics at the same time), which is unavoidable according to the known method, when the transition is allowed to take place with a weft which does not form the end of a repeat.

Claims

Method for weaving face-to-face jacquard pile fabrics with woven-in dead pile ends and a background weave with a repeat of four picks, characterized in that for each transition in the effect of a pile end (51), which could produce a detrimental effect in the pattern on the pile side and/or on the back of the fabrics, the pile end (51) gets a changed weave in order to avoid at least the detrimental effect on the pile side; that each transition in the effect of the pile end (51) is considered as a transition between a first (41, 42, 43, 44) and a second cycle of four picks (45, 46, 47, 48), wherein the pile end (51) has one of the following effects :
- Pile forming over the whole cycle: status code O

- Pile forming over the first two wefts of the cycle and woven into the lower fabric over the last two wefts of the cycle : status code 1 (O)

- Pile forming over the first two wefts of the cycle and woven into the supper fabric over the last two wefts of the cycle : status code 1(B)

- Pile forming over the last two wefts of the cycle and woven into the lower fabric over the first two wefts of the cycle : status code 2(O)

- Pile forming over the last two wefts of the cycle and woven into the upper fabric over the first two wefts of the cycle : status code 2(B)

- Woven into the lower fabric over the whole cycle: status code 3

- Woven into the upper fabric over the whole cycle: status code 4;
that the changed weaves provide a change of the position of the pile end (51) in relation to at least one weft end of the two last weft ends (43), (44) of said first cycle and the two first weft ends (45), (46) of said second cycle; and that the changed weaves provide the following changes (indicated by means of the position, above (B) or below (O), of the pile end (51) in relation to said two last and said two first weft ends) for the following transitions between two cycles (indicated by their status codes) :
- transition from O to 2(B): O-B-B-O becomes O-B-B-B

- transition from 1(O) to O: B-O-O-B becomes O-O-O-B

- transition from 1(O) to 1(O) or 1(B): B-O-O-B becomes O-O-O-B

- transition from 1(O) to 2(O) : B-O-O-O becomes O-O-B-O

- transition from 1(O) to 3: B-O-O-B becomes O-O-B-B

- transition from 1(B) to 2(B): B-B-B-O becomes B-O-B-B

- transition from 1(B) to 4: B-B-B-O becomes B-O-B-O

- transition from 2(O) or 2(B) to 2(B): O-B-B-O becomes O-B-B-B

- transition from 3 to 2(O): B-O-O-O becomes B-O-B-O

- transition from 4 to 2(B): B-B-B-O becomes B-O-B-B
Method for weaving face-to-face jacquard pile fabrics with woven-in dead pile ends and a binding repeat of four picks for the pile ends, characterized in that for each transition in the effect of a pile end (51), which could produce a detrimental effect in the pattern on the pile side and/or on the back of the fabrics, the pile end (51) gets a changed weave in order to avoid at least the detrimental effect on the back; that each transition in the effect of the pile end (51) is considered as a transition between a first and a second cycle of four picks, wherein the pile end (51) has one of the following effects :
- Pile forming over the whole cycle: status code O

- Pile forming over the first two wefts of the cycle and woven into the lower fabric over the last two wefts of the cycle : status code 1 (O)

- Pile forming over the first two wefts of the cycle and woven into the supper fabric over the last two wefts of the cycle : status code 1(B)

- Pile forming over the last two wefts of the cycle and woven into the lower fabric over the first two wefts of the cycle : status code 2(O)

- Pile forming over the last two wefts of the cycle and woven into the upper fabric over the first two wefts of the cycle : status code 2(B)

- Woven into the lower fabric over the whole cycle: status code 3

- Woven into the upper fabric over the whole cycle: status code 4;
that the changed weaves provide a change of the position of the pile end (51) in relation to at least one weft end of the two last weft ends (43), (44) of said first cycle and the two first weft ends (45), (46) of said second cycle; and that the changed weaves provide the following changes (indicated by means of the position, above (B) or below (O), of the pile end (51) in relation to said last two and said first two weft ends) for the following transitions between two cycles (indicated by their status codes) :
- transition from O to 2(O): B-O-O-O becomes B-O-B-O

- transition from 1(O) to 2(O): B-O-O-O becomes O-O-B-O

- transition from 1(O) to 3: B-O-O-O becomes O-O-B-O

- transition from 1(B) to O: B-B-B-O becomes B-O-B-O

- transition from 1(B) to 1(O) or 1(B): B-B-B-O becomes B-O-B-O

- transition from 1(B) to 2(B): B-B-B-O becomes B-O-B-B

- transition from 1(B) to 4: B-B-B-O becomes B-O-B-O

- transition from 2(O) or 2(B) to 2(O): B-O-O-O becomes B-O-B-O

- transition from 3 to 2(O):B-O-O-O becomes B-O-B-O.

- transition from 4 to 2(B):B-B-B-O becomes B-O-B-B.
Method, according to claim 1 or 2, characterized in that the changed weaves are obtained by means of a jacquard device.
Method, according to any of the preceding claims, characterized in that a programmable device connected to a jacquard device is programmed to associate automatically a changed weave with each transitional situation which requires a changed weave, and to transmit the data for obtaining the changed weave to the Jacquard device.
Method according to claim 4 characterized in that the programmable device is so programmed that the choice exists of applying the changed weaves according to claim 1 or according to claim 2, depending on whether it is desired to obtain respectively a fabric with a pile side without detrimental effects, or a fabric with a back without detrimental effects.
Method, according to claim 4 or 5, characterized in that the programmable device is a computer, which is connected to, or is part of a jacquard device.