EP0565122A1 - Double weft weaving process for double velvet with double weft weave and double plush loom with vertically movable weft insertion devices for the execution of the process - Google Patents

Abstract

The invention relates to a working process for the double-bobbin production of a double-plush fabric with a double-weft weave for the active pile threads (P9 or P10) and with tied-in dead pile threads (P10 or P9), the weft-insertion aids being brought alternately to the height (hB1, hB2) of the upper fabric and to the height (h01, h02) of the lower fabric; two weft threads (lB1 and lB2) or (l01 and l02) located one above the other are introduced each time into that upper fabric or that lower fabric, whilst in each repeat, in respect of the two double wefts (lB1, lB2) and (l01, l02) of that repeat, the active pile thread (P9 or P10) is brought above the two weft threads (lB1, lB2) in the upper fabric and below the two weft threads (l01, l02) in the lower fabric. The invention relates, furthermore, to a double-plush loom, in which two or more upwardly and downwardly movable weft-insertion aids can be driven, in order to move these jointly upwards and downwards in an exactly coordinated cycle so as to carry out the working process according to the invention. <IMAGE>

Description

The invention relates on the one hand to a two-weft weave for producing double-piece fabrics without mixed contours, each pile loop can have a different color, and to double-piece fabrics which are woven with such a weave.

The invention, on the other hand, relates to double-piece weaving machines which are provided with two or more weft insertion devices which can jointly carry out an upward and downward movement during the weaving process, in order to weave the two-weft weave according to the invention, the wefts in succession at two different levels by one between the warp threads.

In order to clarify the current state of the art in the field of the invention, the following briefly explains how the double-piece fabrics are manufactured with the aid of known double-piece weaving machines.

Two basic fabrics - referred to as the upper fabric and the lower fabric - are woven on top of one another by interweaving warp threads that extend alongside one another on two levels with weft threads oriented perpendicularly thereto. Before each weft (the insertion of a weft thread between the warp threads), each warp thread is drawn either above the weft height or below the weft height at the point where the weft is to be fired. A weft thread is inserted between the two groups of warp threads - in the compartment. This finally extends across the entire width of the fabric. By choosing the positions of the various warps before each weft, the desired bond between the warps and wefts is obtained. - To form the upper fabric - the above takes place at the height of an upper row of warp threads and - to form the lower fabric - at the height of a lower row of warp threads. The existing weaving machines are z. B. provided with a weft insertion device, which consists of two grippers - namely a transmitter and a slave - which are arranged on both sides of the warp threads at the same height. The two grippers are inserted into the compartment at the same time, while one of the grippers - the encoder - takes a weft thread with them. The two grippers meet in the compartment, and the weft thread of one gripper is handed over to the other gripper - the taker. Then the two grippers are removed from the compartment, so that the weft thread finally moves from one side of the compartment to the other side extends. In the case of looms with a single weft insertion device, the position of the warp threads ensures that the weft takes place alternately in the upper fabric and in the lower fabric. In the so-called double rapier weaving machines, two rapier devices arranged at a fixed height are provided one above the other so that a weft thread can be inserted simultaneously in the upper fabric and in the lower fabric. One speaks of a double weft insertion.

To form the pile of the double-piece fabrics, pile warp threads are bound one behind the other by the weft threads in the upper fabric and lower fabric in such a way that they run from one to the other base fabric. These pile threads are then cut through between the two base fabrics. In order to obtain figures in the pile, several pile warp threads of different colors are provided. If a pile warp thread runs (i.e. is active) between the lower fabric and the upper fabric at a certain location of the fabric, other pile warp threads are integrated in the one base fabric (parallel to the warp threads) in such a way that they are invisible on the top of the fabric (the pile side) are. These pile threads are called dead pile threads. Only the active pile thread is visible, so that it determines the color of the fabric at that location. For this purpose, a jacquard device is used, which can determine the position of each pile thread separately before each shot. The control data of the jacquard device are consequently determined in dependence on the desired figure and the desired binding for the pile threads.

The known double-piece looms are provided with a number of looms that can be moved up and down in order to take a number of warp threads with them during these movements. As a result of the control of these weaving frames, the correct positions of the various warp threads with regard to the weft height are determined so that the base fabrics would be woven in the desired weave. The movement of these looms happens for. B. by means of cams.

In a so-called two-weft weave, the active pile threads are bound one after the other in the upper fabric and lower fabric in such a way that their position with respect to the successive weft threads is repeated every time after two wefts (one repeat). In order to illustrate the state of the art in relation to the binding according to the invention, a known two-weft binding is shown schematically as a cross section in FIG. 1. In this figure, the weft threads are perpendicular to the leaf surface and can be seen in cross section. The warp threads lie in the leaf surface and you can see them as solid lines. The binding warp threads - which are interwoven with the weft threads - and the tension warp threads are not shown. That alone Pile warp threads (P₁, P₂) are shown. This weave is woven with double weft insertion. The successive, double shots are numbered vertically below in the figure. The pile thread (P₂) is active during the first six (double) shots and is bound by the weft (7) in the lower fabric to become active again by the weft (13).

The pile thread (P₁) is tied up in the upper fabric during the first six shots and active during the following six shots (7 to 12), in order to then be tied back into the upper fabric from the weft (13).

This weave can be woven by allowing two different positions of the pile warp threads with respect to the grippers in each weft, namely the positions (of the two grippers) "up" and (between the two grippers) "middle" and "to integrate a pile warp thread in the upper fabric" the positions "bottom" and "center" for integration in the lower fabric and the positions "top" and "bottom" for pole formation. By combining these positions one after the other with a jacquard machine, the fabric of FIG. 1 is obtained.

The disadvantage of this binding is that so-called mixed contours arise. A mixed contour arises at the transition between two different color fields. If a weave repeat (weft 5 - 6) with a figure-forming pole (P₂), which is integrated in the lower fabric for repeats in which this pile thread (P₂) is not a figure (e.g. B. weft 9-10) is followed by a weave repeat (weft 7-8) with a figure-forming pole (P₁), which is incorporated in the upper fabric in repeats in which this pile thread (P₁) is not a figure (e.g. Weft 1 - 2), then at a transition between these repeats (in FIG. 1 a weft 5 - 6 is followed by a weft 7 - 8) a mixed contour occurs. This means that when a color field formed by the pile thread (P₂) is separated in the fabric and a color field formed by the pile thread (P₁), a color mixture is formed on the color field outline. The clear dividing line between these two color fields is disturbed by the fact that a piece of the last pole loop of the pile thread (P₂) within the color field of the pile thread (P₁) and a piece of the first pile loop of the pile thread (P₁) within the color field of the pile thread (P₂) obliquely runs. This unclean transition between two color fields is called a mixed contour.

A number of solutions are known to avoid these mixed contours. To avoid mixed contours, there is a first known way of working in that 3 different positions of the pile warp threads are provided per weft. With this method of operation, a pulley device is required for each pile thread, which, in cooperation with two hooks of the jacquard machine, enables these three positions.

The disadvantage of this solution is that a double capacity of the jacquard machine is necessary, which makes this solution much too expensive.

Another known solution consists in omitting a pole point. The choice of the new, active pole is postponed by one shot while the first pole thread is already tied in. The result can be seen in FIG. The mixed contours no longer appear. A disadvantage of this way of working, however, is that one color point now corresponds to four shots (instead of two shots).
As a result, the pattern fineness is halved. Another disadvantage is that you only get half the pole occupation when changing colors.

Another known solution is described in Belgian patent application no. 09000563, filed on June 5, 1990, which is based on the principle that the overlaid work report of the pile warp threads extends over three shots, while the work report for the basic weave comprises only two shots.

The aim of the invention is to provide a two-weft weave which can be woven with a double weft insertion without mixed contours, each pile loop can have a different color without the disadvantages mentioned above occurring.

The object of the invention is on the one hand a two-weft weave without mixed contours and on the other hand a weaving machine with two or more vertically movable grippers in order to realize the weaving according to the invention, while weaving with this weaving machine brings additional advantages. The two-weft weave according to the invention results in a double-piece weave, which alternately receives two wefts lying one above the other in the upper weave and in the lower weave. Between these two weft threads - parallel to the fabric - there is a dead pile thread. An active pile thread runs in sequence in the upper fabric above the two weft threads, in the lower fabric under the two weft threads, etc.

The problem of the mixed contour generally occurs at a color transition at which an active pile thread is bound in one of the fabrics and another pile thread, which was previously bonded in the other fabric, begins to run towards the former fabric to form the pile.

In the two-weft weave according to the invention, the following situation is given for a color transition: the active pile thread lies on the last weft in which it is active, over the two weft threads of the upper fabric or under the two weft threads of the lower fabric, the next
Weft bound between the two weft threads of the lower fabric or the upper fabric and also remains bound in that way in the same fabric. Both in the upper fabric and in the lower fabric, this pile thread sits between the inner wefts (i.e. the weft threads located along the pile side of the fabric) which belong to successive wefts, whereby the pole pieces, after being cut through, are mainly kept perpendicular to the surface of these fabrics will.

The other pile thread, which was tied up before the transition and becomes active after the transition, lies between the superimposed weft threads in the upper fabric or in the lower fabric during the last weft in which it is tied in and runs above the two on the next shot Weft threads of the upper fabric or under the two weft threads of the lower fabric and further between the two fabrics - each time tied in the above manner - back and forth as long as this pile thread remains active.

This pile thread sits both in the upper fabric and in the lower fabric between the adjacent inner wefts, which belong to successive wefts, whereby the pole pieces, after being cut through, are kept mainly perpendicular to the surface of the fabrics.

The binding according to the invention described here can be realized with the aid of a weaving machine which has two weft insertion devices which can be moved vertically up and down and which is another object of the invention. In addition, the use of such a weaving machine is associated with additional advantages, which are also presented in this description.

European Patent Application No. 88 116629.2, published under number 0362433, describes a weaving machine which is provided with a single device which can be moved up and down to pass the weft threads through the shed.

This weft insertion device is given a movement by known aids, which is matched to the cycle of movement of the loom, the weft thread being inserted alternately at one of two heights in each subsequent compartment and each time a loom that is just moving is coming towards it. The problems that are solved by this invention exist in that the pole length is no longer dependent on the amplitude of movement of the weaving frames, that the cams that give the movement to the weaving frames can be provided with less steep flanks and that a fabric is obtained whose pole is flatter.

The weaving machine according to the invention has two or more vertically movable, superimposed weft insertion devices, which move up and down together in a well-coordinated cycle. In order to produce a fabric with the binding according to the invention, the weft insertion devices are moved up and down in such a way that in the uppermost position of these devices the lowest gripper device reaches approximately in the middle (i.e. half way of the levels in which) the two tissues extend) and that in the lowest position of the weft insertion devices the uppermost weft insertion device comes to a standstill in the middle position mentioned.

This weaving machine has the following additional advantage: the tension warp threads and the dead pile warp threads always remain at the same height. As a result, the looms of the tension warp threads do not need to be raised. Since no lifting needs to be carried out for the binding of the dead pile warp thread, it is possible to achieve this binding with a single-stroke jacquard machine (two possible positions for each pile thread per weft: either above or below the gripper devices). This jacquard machine can then e.g. B. consist of two parts, namely a part for work above and a part for work below.

The middle position of the invention (at the level of the tension warp threads) at work above is the resting state of the jacquard hooks.

Another advantage of this weaving machine according to the invention is that the weaving frames of the binding warp threads have twice as much time to cross as in the known weaving machines, because no lifting of these weaving frames needs to be carried out. At the moment when the grippers insert shots into the lower fabric, the weaving frames of the binding warp threads of the upper fabric run vertically and vice versa.

The above-mentioned advantages have the consequence that the energy consumption of this weaving machine can be lower than that of the known weaving machines.

Finally, it is also an advantage that the loom only needs to move at half the speed and that the dead pile warp threads remain immobile, which of course has an influence on the wear of individual parts, the tearing of warp threads, etc.

Further advantages and features of the weave according to the invention and the weaving machine for realizing this weave are clarified in connection with the detailed description which follows, without, however, the invention being restricted thereby to the specific examples and embodiments which are set out in this description. This description is made clear with the aid of the attached figures.

FIG. 1 schematically shows a cross section through a double-piece weave which is woven in a two-weft weave with a double weft insertion in order to clarify the problem of the mixed contours according to the prior art.

FIG. 2 schematically shows a cross section through a double-piece weave in a two-weft weave with double weft insertion, a mixed contour according to the prior art being avoided by postponing the choice of the new, active pole during a weft.

FIG. 3a schematically shows a cross section through a double-piece weave, which is woven in the two-weft weave with double weft insertion according to the invention, with possible different color transitions occurring.

Figure 3b shows schematically a cross section through the double piece fabric of Figure 3a according to the invention after the pile warp threads have been cut.

FIGS. 4a and 4b schematically show the positions of the weft and warp threads with respect to these weft threads when two successive wefts are made in cross-section when producing a double-piece weave in the binding according to the invention.

In the weave for making double-piece fabrics according to the invention (see FIGS. 3a and 3b), weaving is carried out with a double weft insertion, while the pile warp threads are woven in a two-weft weave with the weft threads. According to FIGS. 3a and 3b, four pile warp threads (P₅, P₆, P₇, P₈) are provided, two of which (P₅, P₆) are integrated in the repeat in the upper fabric where they are not active, and the other two (P₇, P₈ ) are integrated into the lower tissue when they are not active. If one pretends that a specific pile thread is bound in the lower fabric (OW) or in the upper fabric (BW) as a dead pole, the lower fabric OW or upper fabric BW being put in brackets with respect to the respective pile thread, then in FIGS. 3a and 3b shows the following successive transitions between the active pile threads:
from P₅ (BW) to P₆ (BW): repeat 3-4, followed by repeat 5-6,
from P₆ (BW) to P₇ (OW): Repeat 7-8, followed by repeat 9-10,
from P₇ (OW) to P₈ (OW): repeat 11-12 followed by repeat 13-14,
from P₈ (OW) to P₆ (BW): repeat 15-16, followed by repeat 17-18.

The weave is formed by two successive, superimposed weft threads both in the upper fabric and in the lower fabric; these wefts are identified by the consecutive number of the weft at which they are inserted (1 to 23), each weft being referred to as the top or bottom. A repeat is formed by two successive shots and is also denoted by the consecutive numbers of those successive shots, e.g. B. Shot 3-4 (see above). The dead pile warp threads are bound between the upper and lower weft threads, which are two on top of each other. The active pile warp threads are one after the other in the upper fabric above an upper weft thread and in the lower fabric under a lower weft thread of the following weft. If a repeat (e.g. 3-4) in which a pile thread P₅ (BW) is active is followed by a repeat (5-6) in which a pile thread P₆ (BW) is active, the pile thread P₅ (BW ) in the fifth weft in the upper fabric, and the pile thread P₆ (BW) is inserted above the upper weft thread of the fifth weft in the upper fabric, after which it runs into the lower fabric and continues to form a pile.

Since each pole piece extends almost perpendicular to the surface of the tissue after the active pile threads have been cut through between the two fabrics and remains within its own color field, no mixed contours occur. A clean line demarcation is obtained between the two color fields.

If a repeat (7-8) in which a pile thread P₆ (BW) is active is followed by a repeat (9-10) in which a pile thread P₇ (OW) is active, the pile thread P₆ (BW) is already at that ninth weft tied into the upper weave, and the pile thread P₇ (OW) is already passed between the eighth and ninth weft from the lower weave to the upper weave to be guided above the upper weft thread of the ninth weft and further to form a pile. After cutting through the active pile threads between the two fabrics (see FIG. 3b), no mixed contours can be seen in the fabrics during this transition either.

If a repeat (11-12) in which a pile thread P₇ (OW) is active is followed by a repeat (13-14) in which a pile thread P₈ (OW) is active, the pile thread P₇ (OW) - after it is inserted under the lower weft of the twelfth weft in the lower fabric - in the first following weft - the weft (14) - bound in the lower fabric. The pile thread P₈ (OW) is already inserted in the upper fabric at the thirteenth weft above the upper weft thread, in order to then continue to form a pile. Also at this transition, no mixed contours can be seen in the fabrics after the active pile threads between the two fabrics (Figure 3b) have been cut.

If a repeat (15-16) in which a pile thread P₈ (OW) is active is followed by a repeat (17-18) in which the pile thread P₆ (BW) is active, the pile thread P₈ (OW) - after it is inserted below the lower weft thread from the sixteenth weft in the lower fabric - in the first following weft - the weft 18 - is bound in the lower fabric. The pile thread P₆ (BW) is already inserted from the seventeenth weft above the upper weft thread, in order to then run into the lower fabric and continue to form a pile. Even with this transition, after cutting the active pile threads between the two fabrics, no mixed contours can be seen in the fabrics.

In order to realize such a binding according to the invention, a weaving machine with two vertically upwards and downwards movable weft insertion devices, e.g. B. provided gripper devices.

This movement is using known tools, e.g. B. realized a cam system so that the two devices together perform an upward and downward movement, while their movement cycle is designed such that a double shot takes place when the weft insertion devices have reached an uppermost position, and a double shot takes place, when the weft insertion devices are brought into a lower position, etc. The movements of the jacquard device and the weaving frame are influenced in such a way that each time they bring the pile warp threads or the binding warp threads and tension warp threads into the correct position with respect to the weft heights, so that the two Weft threads should come together each time in the upper or lower fabric, and so that the pile warp threads, the binding warp threads and the tension warp threads with respect to the weft threads should be in accordance with the binding according to the invention.

The manner in which the weaving according to the invention is realized with the help of the weaving machine according to the invention is illustrated in connection with the example following here (see FIGS. 4a and 4b). In these figures, a fabric section (weft 1 to 9) woven in the binding according to the invention is shown schematically in cross section, and in the case of two successive double wefts, the positions of the different warp threads with respect to the weft threads at two different heights are made clear in order to realize the binding according to the invention.

h_R =

feste Höhe, auf der sich der Spannkettfaden (S₁) des Obergewebes und der eventuelle, tote Polkettfaden (P₉), die in dem Obergewebe eingebunden werden, während des Webens befinden,

h_R' =

feste Höhe, auf der sich der Spannkettfaden (S₂) des Untergewebes und die eventuellen, toten Polkettfäden, die in dem Untergewebe eingebunden werden, während des Webens befinden,

h_B1 =

Schußhöhe des obersten Schußfadens bei der obersten Stellung der Schußeinführ-Vorrichtung,

h_B2 =

Schußhöhe des untersten Schußfadens bei der höchsten Stellung der Schußeinführ-Vorrichtung,

h₀₁ =

Schußhöhe des obersten Schußfadens in dem tiefsten Stand der Schußeinführ-Vorrichtung,

h₀₂ =

Schußhöhe des untersten Schußfadens in der tiefsten Stellung der Schußeinführ-Vorrichtung,

h₁ =

Höhe, auf die der eine Bindkettfaden (B₁) des Obergewebes bei einem Schuß in jenem Gewebe gebracht wird,

h₂ =

Höhe, auf die der andere Bindkettfaden (B₂) des Obergewebes bei demselben Schuß in jenem Gewebe gebracht wird,

h_1' =

Höhe, auf die der eine Bindkettfaden (B₃) des Untergewebes bei einem Schuß in jenem Gewebe gebracht wird,

h_2' =

Höhe, auf die der andere Bindkettfaden (B₄) des Untergewebes bei demselben Schuß in jenem Gewebe gebracht wird,

h₃ =

Höhe, auf die ein aktiver Polfaden in dem Obergewebe gebracht wird, um diesen abzubinden,

h_3' =

Höhe, auf die ein aktiver Polfaden in dem Untergewebe gebracht wird, um diesen abzubinden.

In order to clarify the following description of this example, a reference axis is drawn to the left of the weft threads in order to indicate the different heights of the warp threads with respect to the weft threads. The following sizes are given on that reference axis:

h _R =

fixed height at which the tension warp thread (S₁) of the upper fabric and any dead pile warp thread (P₉) that are bound in the upper fabric are during weaving,

h _{R '} =

fixed height at which the tension warp thread (S₂) of the lower fabric and any dead pile warp threads that are bound in the lower fabric are during weaving,

h _B1 =

Weft height of the uppermost weft thread in the uppermost position of the weft insertion device,

h _B2 =

Weft height of the lowest weft thread at the highest position of the weft insertion device,

h₀₁ =

Weft height of the uppermost weft thread in the lowest position of the weft insertion device,

h₀₂ =

Weft height of the lowest weft thread in the lowest position of the weft insertion device,

h₁ =

Height to which a binding warp thread (B₁) of the upper fabric is brought with a weft in that fabric,

h₂ =

Height to which the other binding warp thread (B₂) of the upper fabric is brought in the same weft in that fabric,

h _{1 '} =

Height to which a binding warp thread (B₃) of the lower fabric is brought with a weft in that fabric,

h _{2 '} =

Height to which the other binding warp thread (B₄) of the lower fabric is brought in the same weft in that fabric,

h₃ =

Height to which an active pile thread is brought in the upper fabric to bind it,

h _{3 '} =

Height to which an active pile thread is brought in the lower fabric to bind it.

In the weft (1) of the fabric already formed (see Figures 4a and 4b), the pile warp thread (P₁₀) is active, and the pile warp thread (P₉) must be further bound in the upper fabric. The weft (1) was placed in the lower fabric, so that the next weft (I _B1 , I _B2 ) in the upper fabric must be introduced. For this purpose, the weft insertion device is brought into its uppermost position in the subsequent weft - weft threads I _B1 and I _B2 . Before the weft takes place, the dead pile thread (P₉) and the tension warp thread (S₁) must extend in height h _R. The binding warp threads (B₁) and (B₂) cross each other and are attached in height (h₁) and (h₂). The active pile thread (P₁₀) is brought up (h₃).

These different positions are chosen such that the binding warp thread (B₁) and the pile warp thread (P₁₀) extend above the weft height (h _B1 ) of the uppermost weft thread (I _B1 ), that the dead pile warp thread (P₉) and the tension warp thread (S₁) between the weft heights (h _B1 and h _B2 ) of the weft threads (I _B1 ) and (I _B2 ) run and that the binding warp thread (B₂) is below the weft height (h _B2 ) of the lowest weft thread (I _B2 ). As soon as these positions are reached, the shot is fired (I _B1 and I _B2 ).

With the next weft, the weft threads (I₀₁) and (I₀₂) must be inserted in the lower fabric. For this purpose, the weft insertion device is brought into its lowest position, so that the upper weft thread (I₀₁) reaches a height (h₀₁) which corresponds to the height (h _B2 ) of the lower weft thread (I _B2 ) when the weft insertion device takes its top position.

Before the weft takes place, the tension warp thread (S₂) must extend in height (h _{R '} ). The binding warp threads (B₃) and (B₄) overlap and are each brought to the height (h _{2 '} ) and (h _1' ). The active pile thread (P₁₀) reaches the height (h _{3 '} ).

These different positions are selected such that the binding warp thread (B₄) extends above the weft height (h₀₁) of the uppermost weft thread (I₀₁) that the tension warp thread (S2) between the weft heights (h₀₁) and (h₀₂) of the weft threads (I₀₁) and (I₀₂), and that the binding warp thread (B₃) and the active pile thread (P₁₀) are below the weft height (h₀₂) of the lowest weft thread (I₀₂).

As soon as these positions are reached, the shot (I₀₁ and I₀₂) takes place.

After the weft has been made in the lower fabric with the weft threads (I₀₁ and I erfolgt₂), the binding warp threads (B₃, B₄) of the lower fabric can already be brought into position for the next weft in the lower fabric, while the weft in the upper fabric with the weft threads (I _B1 and I _B2 ) is pre-realized.

After the weft has been made in the upper fabric with the weft threads (I _B1 and I _B2 ), the binding warp threads (B₁, B₂) of the upper fabric can already be brought into their position for the next weft in the upper fabric, while the weft is realized in the lower fabric with the weft threads (I₀₁ and I₀₂).

The weaving frames of the binding warp threads therefore have twice as much time for an overlap compared to a binding in which a weft thread has to be bound in the upper fabric and in the lower fabric after each weft.

Another advantage is that the tension warp threads (S₁) and (S₂) always remain in their same place (h _R or h _{R '} ); these weaving frames therefore do not raise. The tension warp threads are used here to pull two pieces apart.

Another advantage is that the dead pile warp threads can always remain in the same position (h _R or h _{R '} ) - at the height of the tension warp threads - to bind the upper or lower fabric. In this way it is possible to carry out the binding according to the invention with a single jacquard lifting machine (jacquard machine with two positions). For example, it can consist of two parts, one for work above and one for work below. The position in which the warp threads are raised (h _R ) is the quiescent state of the jacquard hooks.

An additional advantage is that the effort involved in weaving in the manner explained above can be lower than in the known machines.

Finally, other advantages are mentioned that, on the one hand, the pile threads do not move and that the weaving frames of the binding warp threads only have to move at half the speed, which has an influence on the wear of individual parts, thread breakage, etc.

Some aspects of the invention are given below:
The invention relates to a working method for the two-spool production of a double piece fabric with a two-weft weave for the active pile threads (P₉ or P₁₀) and with bound, dead pile threads (P₁₀ or P₉), the weft insertion aids alternating in height (h _B1 , h _B2 ) of the upper fabric and in the height (h₀₁, h₀₂) of the lower fabric; each time two superimposed weft threads (I _B1 and I _B2 ) or (I₀₁ and I₀₂) are introduced into that upper or lower fabric, while with each repeat the active pile thread (P₉ or P₁ hinsichtlich) with respect to the two double Wefts (I _B1 , I _B2 ) and (I₀₁, I₀₂) that repeat in the upper fabric above the two weft threads (I _B1 , I _B2 ) and in the lower fabric under the two weft threads (I₀₁, I₀₂) is brought.

The invention further relates to a double-piece weaving machine in which two or more weft insertion tools which can be moved up and down can be driven in order to move them up and down together in a well-coordinated cycle for carrying out the working method according to the invention.

Insofar as the above speaks of double-spool or two-spool weaving, this is generally understood to mean weaving with the simultaneous introduction of two weft threads into the upper compartment and then into the lower compartment, regardless of how this introduction takes place, for. B. by means of double grippers or double shooters (two-layer weaving). The double piece fabric according to the invention (with two-weft pile weave) can also be referred to as a jacquard double plush fabric.

Claims (11)

Method for double-spool weaving of a two-weft double piece fabric, in which two weft threads are inserted alternately into the upper fabric and the lower fabric, the active pile threads are brought alternately over the two weft threads into the upper fabric and under the two weft threads into the lower fabric, and that dead pile threads, either in the upper fabric or in the lower fabric, are bound between the superimposed weft threads, characterized in that the two weft threads are brought together, alternately to the height of the upper fabric and to the height of the lower fabric, before they are brought into the Upper fabric, or are introduced into the lower fabric one above the other. Process for the double-reel production of a double-piece fabric, according to claim 1, characterized in that with each weft the two weft threads in the upper fabric and in the lower fabric are introduced only after the binding warp threads, the pile warp threads and the tension warp threads of the relevant fabric with respect to the weft heights in one of these Positioned that the desired binding cartridges of these threads are realized after the weft. A process for the double-bobbin production of a double-piece fabric according to claim 1 or 2, characterized in that when two weft threads (I _B1 , I _B2 ) are inserted at the uppermost level (h _B1 and h _B2 ), the lower weft thread (I _B2 ) is at approximately the same level (h _B2 = h₀₁) as the upper weft thread (I₀₁) when inserting two weft threads (1₀₁, I₀₂) is inserted at the lowest level (h₀₁ and h₀₂). Process for the double-spool manufacture of a double-piece fabric according to claim 1, 2 or 3, characterized in that the tension warp threads (S₁) of the upper fabric and the tension warp threads (S₂) of the lower fabric can always remain at their respective respective heights (h _r and h _{r '} ) during the production of the double-piece fabric. Process for the double-spool manufacture of a double piece fabric according to claim 1, 2, 3 or 4, characterized in that the dead pile warp threads which are bound in the upper fabric and the dead pile warp threads which are bound in the lower fabric always open during the manufacture of the double piece fabric their respective respective heights (h _r and h _{r '} ) can remain. Process for the double-spool manufacture of a double piece fabric, according to claim 1, 2, 3, 4 or 5, characterized in that the tension warp threads (S₁ and S₂) are used to pull the upper fabric and the lower fabric apart. Double-piece weaving machine provided with two devices for inserting a weft thread between the warp threads, these devices being drivable to insert the two respective weft threads together, one above the other, between the warp threads after they have been brought to different heights with respect to the weft heights of both weft threads by means of looms for the weaving of a double-piece fabric, characterized in that the two devices for inserting a weft thread can be driven together in an upward and downward movement, while being driven, alternately in a highest position and in a lowest position to be able to introduce the two weft threads one above the other between the warp threads, two weft threads being brought alternately into the upper fabric and the lower fabric, and that the uppermost weft thread (I₀₁) in said lowermost position in height (I ₁) is introduced, which is approximately with the height (h _B2) is identical on which the bottom weft yarn (I _B2) is introduced in said uppermost position. Double-piece weaving machine according to claim 7, characterized in that the dead pile warp threads do not need to be raised in order to bind them in the upper fabric or in the lower fabric. Double-piece weaving machine according to claim 7 or 8, characterized in that the different positions of the pile warp threads can be determined with a single jacquard machine. Double-piece weaving machine according to claim 9, characterized in that the jacquard machine consists of a part for the upper fabric and a part for the lower fabric. Double-piece weaving machine according to claim 9 or 10, characterized in that the level for incorporating dead pile threads in the upper working part corresponds to the resting state of the jacquard hooks.

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