EP2992128B1 - Method for inserting weft ends in a weaving machine having additional weft effects - Google Patents

Description

Technical area

The present invention relates to a method for inserting weft thread ends on a weaving machine with additional weft effects.

State of the art

In weaving machines, it is known in the prior art to include additional threads extending substantially in the warp direction in such a manner to the weave that certain additional impact effects are achieved. For this purpose, these effect threads are placed in the weft direction before the entry of a weft thread for each cycle of movement of the loom in another position.

For example, a method of weaving patterning and a weaving machine for producing fabrics having such auxiliary shot effects show the patent applications WO 2012004021 A2 and DE 10 2010 007 048 A1 , The process for fabric production according to WO 2012004021 A2 Is characterized in that an effect thread is positioned above the weft thread to be introduced and thereby emerges in the vertical direction from a one-sided upwardly open Rietlücke formed by reed teeth. After a shift of the effect thread in the weft direction of this is positioned below a next to be entered weft thread and immersed in another similarly formed Rietlücke.

In order to generate the movement sequence according to the described method, a guide means of the effect thread is moved in the vertical direction and in the weft direction. The loom according to WO 2012004021 A2 includes a displacement drive, which drives a displacement device in the weft direction, on which at least one guide means is provided, with which an effect thread can be moved in the weft direction and positioned vertically.

For fabrics with additional weft effects, it is now additionally provided to insert weft ends into the shed in order to form a so-called insert edge.

Fabric with insert edge and devices for forming such insertion edges are, inter alia, from EP 0 149 969 A1 , of the JP 2112446 A as well as the US 5,158,119 A known.

In these documents it is disclosed that registered weft threads are detected by holding means. The holding means then bring the weft thread into a position in which it is cut. The cut-off weft end is then grasped by a loading means - for example a hooked or looped needle - and inserted into the shed.

In the case of weave patterns with additional shot effects, two directly successive weft threads in the fabric should as a rule have bonding points with the effect thread. For this purpose, the respective effect thread between the two in the fabric successive weft threads must be positioned vertically and in the weft direction. As the machine speed increases, however, less and less time is available for positioning the guide means. In order nevertheless to be able to bring the effect thread into the correct position between the formation of bonding points with two weft threads following each other in the fabric, it is therefore provided to realize a movement cycle without weft insertion between two movement cycles with weft insertion.

If these fabrics are also to have an insert edge, certain problems arise. It has been found that the insertion edge is uneven when the cut end of the thread last inserted weft thread is inserted into a shed and struck there by the reed, if in this shed no registered weft thread is present.

Object of the present invention is to provide a method by which tissue can be produced with additional bullet effects and good quality of the insert edge.

Description of the invention

The object is achieved by a method according to the independent claim.

In the method of loading weft ends into a loom of a loom, the shed is formed by shed-forming means which vertically move warps in a known manner. In the method, a weft thread is selected by means of weft selection means before each weft insertion. The weft selection means may be electromechanical or electropneumatic means well known to those skilled in the art. In the method, after the formation of a shed, a first weft insertion takes place. For this purpose, weft insertion means are present on the weaving machine. These may be already known mechanical or pneumatic weft insertion means. The first weft thread is struck by a Webblatteinrichtung to a fabric edge.

The damaged first weft thread is then held in a certain position with holding means for the weft thread in the region of the fabric edge. These holding means may be, for example, mechanical thread clamps or thread guide elements. However, it can also be used air nozzles that hold the thread in a specific position.

After the weft insertion - ie immediately before or after the reed stop - a change of the shed takes place, in which the position of the warp threads by the shedding means changes from top to bottom. The method further provides that the first weft thread is displaced by means of the holding means for the weft thread. For this purpose, the holding means is provided with a mechanical or pneumatic control. These can be, for example, cam gears, linear motors or pneumatic valves for controlling air nozzles.

During the displacement, the first weft thread reaches a position in which it is cut with the help of a weft cutter. The result is a first weft end, which is then detected by an insert. The insert means may be a loading needle with thread hook or thread eyelet. However, it can also be provided an air nozzle, which detects the first weft end by means of an air jet.

With the help of the insertion means, the first weft thread end is then inserted into the shed.

The method further provides that a second weft thread is selected by means of the weft selection means.

The second weft thread is entered into the shed with the weft insertion means. Subsequently, the second weft thread is struck by means of Webblatteinrichtung together with the first weft end to the fabric edge The battered second weft thread is then held with the holding means for the weft thread in the region of the fabric edge in a certain position. After the weft insertion - ie immediately before or after the reed stop - the position of the warp threads with the help of the shedding means changes from top to bottom - a new shed is formed.

Then the second weft thread is displaced by means of the weft thread holding means.

During the displacement, the second weft thread reaches a position in which it is cut with the help of the weft cutter. The result is a second weft end, which is then detected by the insert.

With the help of the insertion means, the second weft end is then inserted into the shed.

The method is characterized in that between the two successive weft insertion operations of the first and second weft thread another reed beating takes place by the Webblatteinrichtung, but no weft thread is struck against the fabric edge. This is achieved in that after the previous Webblattanschlag no additional weft thread is entered into the shed. To achieve this, for example, the weft selection means are controlled so that no weft insertion takes place for a cycle of movement of the loom. There is thus a motion cycle with a so-called empty shot in the process. As a cycle of motion of the loom here the period is referred to, which lies between two Webblattanschlägen. The main drive shaft of the loom makes a full turn.

The inventive method further provides that between the two successive weft insertion operations of the first and second weft yarn extending in the warp direction effect yarn is moved in the weft direction of the loom. The weft direction is the direction in which the weft thread is entered.

In the context of the present invention is the speech of procedures in the normal weaving operation, that is, in the normal weaving pattern with the weaving machine running and not only in connection with processes in case of malfunction.

The method according to the invention thus also encompasses a method in which a continuous change between empty shots and normal weft insertion takes place over a large number of weft insertion, wherein no weft thread end is inserted into the sheds into which no weft thread is inserted.

For example, a displacement device already known from the prior art can be used with a guide means for the effect thread for the displacement process.

The weaving pattern including the shifting operation and the loading operation can be performed by means of data sets via a control of the weaving machine according to, for example, FIG WO 2012004021 A2 be made. The pattern-controlled activation of the holding means for the weft thread can be realized by the insertion of additional data in the sample cartridge of the respective tissue. When empty shot, the holding means are controlled so that the weft thread can not be cut and detected by the insert. This can be done for example by the control of electromagnetic means in the cam gear. It can be lifted, for example by an electromagnet which acts on the roller lever of the cam gear, the roller of the cam gear as needed in the weave pattern of the cam. As a result, the weft thread with the holding means remains in a position on the fabric edge, in which it can not be detected by the insert. The insert means itself-for example a cam gear controlled by a loading gear - can thus also run in the empty-shot mode - ie without weft insertion, without a weft end being inserted.

The FIGS. 1 and 2 show in partial views of a loom for performing the method. The weaving machine includes shed drives 9 for driving shed forming means 4, by the vertical movement of which a shed 1 1.1.1.2 bounded by warp threads 1 is formed. The shingles 9 known to the person skilled in the art can, for example, consist of a group of levers and rods which are arranged below the shed forming means 4 and which transmit the drive movements of a shedding machine 23 to the shed forming means 4.

The shed forming means 4 consist in the present example of known heddles with strands, through the Litzenaugen the warp threads 1 are performed. Furthermore, facilities for the entry of a weft thread 3 in the shed 1.1,1.2 in a weft direction 12 are present. In the example in the FIGS. 1 and 2 a device is shown with grippers, which are pushed in a known manner via not shown gear and two drive wheels from both sides of the loom in the shed 1.1,1.2. The weft thread 3 is fed in this embodiment of a shot coil on a Vorspuler and a selection device for the Schussfadenart 19 one of the two grippers and transferred to the other gripper in the machine center. Of course, the use of different weft types for different movement cycles is conceivable. The selection and presentation of the weft threads 3 to a gripper takes place, for example, by means of a weft selection device for the type of weft thread 19. Such designs are known to the person skilled in the art.

The control device 8 of the loom is further equipped with input means 21 and storage means 22.

Of course, the weft insertion devices may also be designed as weft protectors, projectiles or pneumatic weft insertion devices.

On the loom according to the FIGS. 1 and 2 Furthermore, a Webblatteinrichtung 7,7.1,10 for striking the weft thread 3 to a fabric edge 13 is present, which consists of a Webblattlagerung 10 with reed teeth 7 and a Rietbund 7.1. These reed teeth 7 form between one side upwardly open receiving spaces, so-called Rietlücken 14, so that threads in the direction of the warp threads 1 from back to front through the Loom running, dip from above into these Rietlücken 14 and thus can be performed by the reed teeth 7 in the weft direction 12.

The reed teeth 7 are attached via the reed collar 7.1 to the Webblattlagerung 10 and perform together with this at each cycle of the weaving machine a stop movement 15 - 15.1. Finally, in the present embodiment according to the FIGS. 1 and 2 a displacement device 5 with a prismatic guide mounted on the frame of the heald, are attached to the three guide means 11, with which three effect threads 2 can be moved in the weft direction 12 by the path A.

As a guide means 11 needles with eyelets 18 are used in the present embodiment, one or more of which are attached at one end to a needle bar. This needle bar forms together with a running in the weft direction 12 prism-shaped linear guide the displacement device 5, which is fastened together with an electric motor drive as a displacement drive 6 at the front of a heald. As a displacement drive 6, a linear drive is provided, the stator is integrated in the frame of the heald or in the prism-shaped linear guide.

By the displacement drive 6, which drives the displacement device 5, displacement paths A of the effect threads 2 can be predetermined in each movement cycle of the weaving machine. The respective displacement A is derived via a control device 8 and the displacement drive 6 for each movement cycle of the loom of a data set. A computer program which runs in the control device 8 calculates the displacement paths A from the data records.

Values for controlling the weft selection means and the means for holding and inserting the weft threads can also be stored in the data records.

Claims (1)

1. Method for tucking-in weft thread ends into a loom shed (1.1, 1.2) of a weaving machine, wherein the loom shed (1.1, 1.2) is formed by shedding means (4) by which warp threads (1) are moved vertically, and wherein with the aid of weft thread selection means(19) a first weft thread (3) is selected, which is inserted into the loom shed (1.1, 1.2) by means of weft insertion means and is beat-up against a fabric fell (13) with a weaving reed device (7, 7.1 ,10), and wherein the beat-up first weft thread is held in a certain position in the area of the fabric selvedge with holding means for the weft thread, wherein after the weft insertion a change of the loom shed (1.1, 1.2)is carried out by the shedding means (4), and wherein it is further provided that the first weft thread is displaced with the aid of the holding means for the weft thread so that the first weft thread comes into a position in which it is cut with the aid of a weft thread shear, wherein a first weft thread end arises, which is then grasped by a tucking means, by which the first weft thread end is tucked into the loom shed (1.1, 1.2), furthermore a second weft thread is selected with the aid of the weft thread selection means (19) and is inserted into the loom shed (1.1, 1.2) with the weft insertion means, whereupon the second weft thread in common together with the first weft thread end is beat-up against the fabric fell (13) by means of the weaving reed device (7, 7.1, 10), and whereupon the beat-up second weft thread is held in a certain position in the area of the fabric selvedge (13) with the holding means for the weft thread, and wherein after the weft insertion a change of the loom shed (1.1, 1.2) is carried out by the shedding means (4), and wherein the second weft thread with the aid of the holding means for the weft thread is displaced into a position in which it is cut with the aid of the weft thread shear, so that a second weft thread end arises which is then grasped by the tucking means and tucked into the loom shed (1.1, 1.2), wherein in the normal weaving operation, between the two successive weft insertion processes for the first and second weft thread, the following processes occur:

   a further weaving reed beat-up (15.1) by the weaving reed device (7, 7.1, 10) takes place, wherein however the weft thread selection means (19) are actuated in such a manner so that no weft thread (3) is inserted and beat-up against the fabric fell (13), and

   the holding means for the weft thread are actuated in such a manner so that no thread end of the first inserted weft thread is tucked into the loom shed (1.1, 1.2), and

   an effect thread (2) extending in the warp direction for forming additional weft effects is displaced in the weft direction (12) in the weaving machine by means of a displacing device (5).

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