DE102015213015B3 - loom - Google Patents

Abstract

A weaving machine with shed forming means (10, 25) for forming sheds (3) between warp threads (1) drawn from a thread supply (9), weft insertion means (20) for inserting weft threads (2) in the form of tapes into the formed sheds (3), and a withdrawal device (30) for removing the warp and weft threads (1, 2) formed by the fabric (4) after a weft insertion. The loom comprises a measuring device (40) for detecting geometric parameters, in particular the width, of a weft thread (2) before its entry into the shed (3), and an evaluation device (45) for evaluating the detected measurement results. On the weaving machine there is a control device (50) connected to the draw-off device (30) for controlling a movement of the fabric (4) including the take-off on the basis of the evaluated measurement results.

Description

The present invention relates to a weaving machine for the processing of tapewise weft threads - i. According to the preamble of claim 1. Here are the shedding device, the weft insertion device and the essential parts of a trigger device known devices on weaving machines. Also, the construction of a fabric of warp and weft threads in the form of tapes, such as carbon or fiberglass tapes, has been known for some time. Such tapes are made for example of carbon rovings, which are solidified in the spread, parallelized state with an impregnation. The width of such tapes is e.g. a few millimeters to more than an inch. Fabrics made of carbon tapes are used, for example, for lightweight construction applications in the aircraft or motor vehicle sector.

In the present case, both the terms "weft" and "tape" are used, since the invention relates to the entry of weft threads in the form of tapes. For the warp threads can be used any threads, for example, wide and / or thick threads, but preferably threads in the form of tapes.

For the insertion of weft threads in the form of tapes in an open, formed by raised and lowered warp shed gripping gripping and clamping devices are provided, which take the front tape end coming either from the entry side or from the opposite side (through the open shed) coming and pull through the shed.

In the embodiment according to EP 1 838 911 B1 The registered tape is clamped in thread clamps on both sides of the shed and is transported by moving these thread clamps by a fixed predetermined distance in the weaving or withdrawal direction (machine direction) to the rear edge of the fabric or to the binding point of the fabric. Since only the outer ends of the cord-shaped weft thread are detected and transported in the direction of the fabric trailing edge, there is in the EP 1 838 911 B1 described method, in principle, the risk that the tapes over the fabric width away are not absolutely straight brought to the tissue trailing edge, but that the fabric-lying area of the shot tapes in the tissue plane forms an arc. According to the weaving machine EP 1 838 911 B1 is trying to reduce this effect by the warp threads in the vertical direction through the loom, the shot tapes are also arranged vertically with their width direction and registered above the existing fabric trailing edge in the shed. The transport of the registered belt-shaped weft threads to the fabric trailing edge is thus supported by the force acting on the tapers of gravity.

The DE 102011009765 B3 discloses an apparatus and method wherein the web is moved back toward the weaving direction a predetermined distance towards the just-entered weft-shaped weft until the front longitudinal edge of the tape and the back fabric edge abut each other.

In both cases, after the weft insertion, a crossing of the warp threads with the weft threads takes place by closing and opening the shed by means of the shed forming device. The fabric, which has now been extended by one tape width, is moved on or off a little to make room for the next weft insertion.

A disadvantage of fabrics produced in this way may be that after the weft insertion, the subsequent positioning of the tapeformed weft threads with respect to the fabric trailing edge takes place independently of the actual instantaneous geometry of the tape. In practice, tapes with widths of for example 20 mm - 50 mm are used. Such tapes have - caused by the nature of the production - a certain - no longer negligible - dispersion in the width over the length of the tape. For certain applications, it may also be advantageous to use tapewise weft threads with specifically selected, different widths within a fabric alternately or in a predetermined sequence. There are also fabrics in which there should be a certain predefined distance between successive tapeless weft yarns. If the width of the tapes fluctuates, there is a risk that this distance will not be uniformly equal to the predefined value.

The EP 1 838 911 B1 discloses a device with sensors that measures the width of the tapes in weaving operation. Depending on the measured width special feeders for the warp threads are controlled such that the winding of the fabric can be done without tension or even with an excess of warp threads. An exact positioning of the longitudinal edge of the tapewise weft threads without spacing or with a predetermined distance from the rear edge of the fabric depending on different widths of the tapeformed weft threads is thus not possible.

It is an object of the present invention to provide a loom, in which the tissue formation using tapeworm wefts to different geometric Parameters of the tapes, especially adaptable to different widths.

This object is achieved by the features of claim 1. In this solution, the advantages are in particular that the actual width and in particular the width variations of the tapes to be introduced into the tissue can be taken into account, since the tape and the tissue are evaluated on the basis of the evaluated Measurement results with varying - and not fixed according to the prior art - path feed can be moved towards each other. In this way, for example, a more closed tissue image can be obtained, for example in the event that the instantaneous width of the tap to be inserted should be reduced.

Overall, increased by the invention, the flexibility for the weft insertion considerably, since the trigger means can be given via the control device based on the evaluated measurement results commands for the tissue advance, which take into account the respective actual tape width.

Alternatively, but preferably in addition to the width detection, the measuring device is designed to detect other geometric parameters, such as holes and / or splices in the weft, the latter caused by detachment of single or multiple filaments from the tape composite.

According to an advantageous embodiment of the invention, the measuring device is based on an optical measuring method. This may in particular be an optically scanned measuring field, which preferably extends over the width of the tape. A corresponding measuring device is for example a precision optical micrometer.

According to one alternative, the measuring device works acoustically, in particular with the aid of ultrasound. Depending on the wave propagation of the ultrasound can be concluded on the width of the scanned tapes.

Also conceivable is a line scan camera with combined pattern recognition software.

Another method of measurement is based, for example, on more tactile - ie non-contactless - scanning of the weft thread (tapes) to be entered.

Particularly preferably, the measuring device is designed such that the width of the weft to be measured before and / or during its entry is detected continuously. In this way, a continuous measurement is possible, in which all variations to the tape width can be detected. The corresponding evaluation options are considerably extended as a result.

The measuring device according to the invention is preferably arranged such that it is capable of measuring width values of the weft thread to be introduced next and / or of the currently inserted weft thread, wherein the measurement on the moving weft thread can be undertaken over the entire length to be inserted. As a result of this measurement, immediately following the weft insertion on the basis of the evaluated measurement, the tissue can be moved to this tape by a distance dependent on the evaluation result. Subsequently, the fabric including the previously registered tape is fed in the warp direction. For these transport operations, a drivable take-off roll and advantageously also a fabric clamp are provided as part of the take-off device. The tissue clamp is advantageously arranged in the region of the tissue-trailing edge extending in the weft direction and prevents displacement of the last-time weft-shaped weft threads introduced into the tissue during tissue displacement. In the event that the aforementioned relative to each other of moving tape and tissue is not performed (for example, because the distance between the tape and fabric is already as desired), the trigger means the fabric including the previously registered tap immediately in the withdrawal direction to a continue or advance the route dependent on the evaluation result.

To produce a reversing tissue displacement, it is advantageous to provide, instead of a reversing rotation of the take-off roll, a pendulum movement of intermediate deflection rolls in the warp thread course or in the course of the fabric. The extraction device comprises in this case a pendulum mounted and reversibly driven deflection roller, which is arranged in the fabric path between the shed or between the fabric clamp and the driven take-off roll.

Preferably, the measuring device is arranged on the entry side of the weft thread or tapes and in this case advantageously aligned in the warp direction, ie transversely to the weft direction. The measuring device is thus accommodated even in confined spaces and yet able to reliably detect the entire width of the weft threads.

Alternatively, the measuring device is arranged below and above the warp threads and in this case advantageously in the region of that longitudinal edge of the fabric which is first crossed by the tape during weft insertion. In this way, the currently pulled through the shed tape almost be measured over its entire length in terms of its width.

The evaluation device is preferably designed such that it is able to calculate the minimum width and / or the maximum width of the weft thread to be introduced. From all recorded measurement data to a weft, these extreme values can be easily determined in order to control the trigger device according to the desired fabric image, for example, to generate a desired, constant distance between the successive weft threads. For this purpose, the maximum width of the current weft yarn is determined and the fabric transport in the forward direction (possibly with previous transport in the backward direction towards the tape) adjusted according to the desired distance.

Alternatively or additionally, the evaluation device is advantageously designed such that it is able to calculate a mixed value based on a plurality of measured values of a weft thread to be introduced or inserted, in particular its average width. When using this mean value, the withdrawal device can be controlled in such a way that a uniform optical weave pattern is obtained with the spacing of the currently last inserted weft thread or tape with respect to the tissue trailing edge matched to said mean values. In this case, this distance can also be set such that the respective weft thread rests on the fabric rear edge in accordance with the determined mixed value, possibly with gaps, depending on the width variations of the tape and the contour of the rear fabric edge.

As an alternative to or following a relative movement of weft thread and tissue last entered, the fabric before the next weft yarn entry by means of the driven trigger device, be moved so that the next weft yarn over its entire weft length without any gap formation with the fabric trailing edge or with a Distance to the tissue trailing edge is entered.

Also, with existing width variations of the tapes fabric images can be realized in which the tapes abut partially with their two longitudinal edges of the adjacent tapes, while narrower tape sections form corresponding gaps.

Advantageously, the evaluation device and / or the control device are designed and set up to stop at least the further weft insertion and the removal device when the weft widths exceed and / or fall short of and / or output a predetermined signal. The evaluation unit and / or the control device are therefore preferably capable of stopping the weaving process on the basis of determined extreme values with regard to the tape width, in order thus to avoid faulty production.

Comparable to this, the evaluation device is preferably designed such that it is capable of recognizing errors of the weft to be inserted, for example holes and / or splices, in order to trigger a predetermined action of the weaving machine in such a case. Such an action may be, for example, the stopping of the weft insertion device and / or the output of a signal, for example, to summon machine operator personnel.

In the following the invention will be described in more detail with reference to an embodiment. Show it:

1 a schematic plan view of a loom

2 a schematic view of the loom according to 1 from the feed side of the warp threads

3 a schematic cross section through the loom according to 1 and 2 with view in weft direction.

In the 1 . 2 and 3 is a loom for warp and weft threads in the form of tapes shown schematically. The tapes consist for example of carbon and / or glass fibers. Such a weaving machine is also called a tape weaving machine. The embodiment of the weaving machine described here can alternatively also be used for fabrics in which only the weft threads are present in the form of tapes, while the warp threads are in the usual thread form, but preferably in the form of coarse, that is to say thick and / or wide threads come.

Several side by side running warp threads 1 are in rotating supply spools 9 held and in the warp direction 6 (Also called machine direction or Webrichtung) to a shedding device 10 . 25 transported. This includes strands, not shown, through which the warp threads 1 threaded through it. The strands are preferably in - schematically illustrated as a frame - heald frames 25 retracted and with the help of a drive 11 alternately raised or lowered, so that the guided through the strands warp threads 1 in a known manner a shed 3 train between themselves. If one half of the warp threads 1 in their upper maximum position and the other half in their deflected lower maximum position, a weft thread 2 through the shed thus formed 3 be guided. For stocking the weft thread 2 , in the present case as a tape, is one about an axis of rotation 8th rotating supply spool 7 provided, which is placed on one side of the loom. The warp threads 1 can instead of the supply spools 9 Alternatively, be kept on a common storage device, such as a warp beam.

To enter a weft thread 2 in a shed 3 is a weft insertion device 20 provided, which is a drive 22 , one with the drive 22 connected rapier rod 24 and one at the free end of the rapier bar 24 provided gripper head 23 includes. The rapier rod 24 is by means of the drive 22 back and forth through the open compartments 3 mobile. Instead of a rapier rod 24 Alternatively, it is also possible to use a rapier band, which may however have to be guided on its way through the shed.

Before the weft insertion is first of the weft yarn package 7 provided weft 2 in the region of its free end by means of a clamping and cutting device shown only schematically 21 held, whereupon the rapier head 23 through the shed 3 passes through and this free end of the weft 2 grips and pinches. The clamping and cutting device 21 in turn, then leaves the free end of the weft 2 go, so the rapier head 23 the weft 2 through the shed 3 can pull. Then the shed becomes 3 closed by the warp threads 1 be moved downwards or upwards. In addition, the clamping and cutting device jams 21 on the side of the weft bobbin 7 the weft 2 and separates the previously entered weft thread 2 from that of the weft bobbin 7 provided endless weft 2 ,

In the 2 is schematically from the back of the loom, the shed 3 shown that from alternately moving up and down warp threads 1 is formed, so that from the weft bobbin 7 replenished weft 2 through the shed 3 can be promoted. For clamping and releasing point the jaws of the rapier head 23 an only schematically indicated pivot point 29 on. Of course, purely linear movements of the jaws of the gripper head 23 conceivable. Clamping and loosening of the jaws can for example be done by means of a mechanical control device which is arranged outside the shed; However, there are also pneumatic or electro-mechanical control devices possible.

In an alternative, not shown, the weft 2 gripped by a gripper, which has not previously driven through the shed in the direction of the weft thread, but is arranged on the side of the weft yarn spool, there detects the weft end, transported through the shed, lets go of the weft and then moves back without weft in the direction of the weft yarn spool ,

The registered weft thread 2 is still on the fabric 4 to tie. For this purpose, before or during closing the shed 3 the tissue trailing edge or the binding point 5 with the tissue 4 towards the entered weft thread 2 too moved. This is the tissue 4 over its entire width against the warp direction 6 about a reverse distance 38 to the previously entered weft thread 2 pushed, for example, the tissue trailing edge 5 at the longitudinal edge of said weft thread 2 is applied. Preferably, the tissue is 4 by means of one of a drive 35 powered tissue clamp 36 clamped (s. 1 and 3 ). Then the possibly existing clamping through the tissue clamp 36 lifted and this even further against the warp direction 6 advanced so far that the tissue clamp 36 the said weft 2 can grasp and pinch. Subsequently, the tissue clamp 36 including the clamped tissue 4 in the warp direction 6 around the forward link 39 moved, leaving the next shed 3 can be formed.

The thus constantly growing tissue 4 is on a take-off roll 32 wound up by a drive 31 around a rotation axis 33 is driven in rotation. To the forward and backward movement of the tissue 4 to produce, in the present embodiment, a pendulum motion of intermediate guide rollers 34 . 37 realized in Kettfadenverlauf or in the fabric progression. This pendulum movement of the guide rollers 34 . 37 In the present case, this is actively realized by means of a reversing rotary drive (not shown in the figures), the two guide rollers 34 . 37 moved synchronously. The take-off roll 32 as well as the tissue clamp 36 and possibly the guide roller 34 are part of a trigger device 30 , wherein the drives of these devices must be matched exactly. This takes over a control device 50 (See below in connection with the explanation of the invention).

The guide roller 34 is in the fabric path between the shed 3 and the take-off roll 32 arranged. In this area is also the tissue clamp 36 , which preferably in the area of the tissue trailing edge 5 is arranged. The optional surrounding roll 37 is in the rear area of the weaving machine between the heald frames 25 and the supply spools 9 arranged.

In principle, it is also possible for a pendulum movement of the guide rollers 34 and 37 to dispense, in which case the forward and backward movement of the tissue 4 by appropriate control of the drive 31 for the take-off roller 32 must be done. For the compensation in the rear area of the machine then eg corresponding drives for the supply spools would be 9 required.

It has now been shown that in particular the width of the weft threads 2 production-related fluctuations, so that at fixed predetermined distances 38 (for the backward movement) and 39 (for the subsequent forward movement) arise uneven tissue images, which is not desirable for all applications.

According to the invention therefore a measuring device 40 for detecting geometric parameters, in particular the width, of the weft threads 2 before their entry into the respective formed shed 3 intended. In the present embodiment, the measuring device 40 between the weft bobbin 7 and the clamping and cutting device 21 below the weft 2 intended.

The measuring device 40 in the present case is based on an optical measurement principle and in this case it scans the weft thread 2 from. For example, the measuring device 40 be designed as a precision optical micrometer. The weft thread 2 back reflected optical signals are from the measuring device 40 receive. Alternatively or additionally, above the weft thread 2 a receiver 41 arranged (in 2 shown in dashed lines). In principle, measuring devices 40 for detecting geometric parameters of an elongated sheet-like structure such as those of a tap known and need not be explained in detail here.

The of the measuring device 40 measured values or measurement results are presently sent to an evaluation device 45 forwarded, which evaluates the measurement results and the results of the evaluation (which are also referred to herein as evaluated measurement results) to a control device 50 forwards. The control device 50 stands with the trigger device 30 communicates and controls the movements of the tissue 4 by making the oscillating reciprocating motion of the deflecting rollers 34 . 37 and possibly the tissue clamp 36 and also the winding up of the fabric 4 on the take-off roller 32 controls. This is the control device 50 with the drive for the pendulum movement of the guide rollers 34 . 37 in conjunction and possibly with the drive 35 who the tissue clamp 36 drives, as well as with the drive 31 that is the take-off roll 32 drives,

In general, it should be noted that the signal and control lines in the 1 and 2 are shown with dash-dotted lines.

The measuring device 40 is preferably for continuous measurement of the geometry of the weft 2 educated. Thus, all deviations from the ideal shape (width, holes, lateral flaking) are reliably detected. In this case, the measurement is preferably carried out when the weft 2 at the measuring device 40 is passed.

The continuous measurement here also expediently comprises the measured values of that portion of the weft thread in the measuring range 2 , which is the next to be entered weft 2 heard), while this still from the clamping and cutting device 21 is clamped. The relevant measured values are also preferred by the evaluation device 45 taken into account, so that measured values over the entire length of the weft thread to be entered next 2 available.

The evaluation device 45 is preferably designed such that it is able to calculate the minimum width and / or the maximum width of the weft thread to be introduced. Alternatively or additionally, the evaluation device 45 For example, a mixed value based on several measurements of a weft 2 calculate, in particular its average width.

Based on the evaluations of the evaluation device 45 can drive the guide rollers 34 . 37 and possibly the drive 35 the tissue clamp 36 from the controller 50 be driven to the tissue 4 based on the determined weft thread width (for example, based on the determined weft thread width extreme values or a mixed value) by an adapted distance 38 contrary to the warp direction 6 to go back. Also the subsequent countermovement 39 of the tissue 4 in the warp direction 6 is adjusted accordingly, so that the forward distance 39 as well as the reverse distance 38 varies depending on the evaluation. In contrast to the prior art are thus no constant, predetermined movements of the tissue 4 provided after each weft insertion, but adapted to the actual width of each previously entered weft movements. Also the winding up of the fabric 4 on the take-off roll 32 and the pendulum movement of the guide roller 34 between take-off roll 32 and tissue clamp 36 are controlled depending on the currently determined weft width. The drives with which the various movements of the assemblies of the loom described above are controlled, are preferably designed as individually controllable motors or motor-gearbox combinations, preferably their signals from the control device 50 to get. These drives are designed so that they - as needed - perform reversing pivotal or linear movements.

The control device 50 can the trigger device 30 , in particular the guide roller 34 and the tissue clamp 36 , so drive that the tissue 4 before the next weft insertion is placed in a variety of ways. For example, it is possible that the tissue 4 - By constant consideration of the width of the respective weft threads 2 - has no gaps. Alternatively, the tissue becomes 4 placed in front of the respective next weft insertion such that there is always a distance of each weft thread 2 to the tissue trailing edge 5 exists, leaving a fabric image with gaps between successive weft threads 2 results. According to a further alternative, the extraction device 30 controlled so that along the currently registered, swaying in width weft thread 2 one or more gaps with the tissue trailing edge 5 are formed, wherein in the remaining areas of this weft thread 2 at the tissue trailing edge 5 abuts and / or even with the tissue trailing edge 5 Overlap areas forms.

Mixed forms of the above tissue images by appropriate adjustment of the control device 50 are easily possible.

The evaluation device 45 and / or the control device 50 are preferably designed and set up, at least the further weft insertion and the withdrawal device 30 to stop when exceeding predetermined and / or undershot predetermined weft widths and / or output a predetermined signal. Likewise, it is advantageous if the evaluation device 45 Error of the weft thread to be entered 2 , For example, holes and / or splices, and can detect a predetermined action of the weaving machine is able to trigger, in particular via the control unit 50 ,

LIST OF REFERENCE NUMBERS

1

 warp

2

 Weft threads (tapes)

3

 shed

4

 tissue

5

 Tissue trailing edge

6

 warp

7

 Weft cheese

8th

 axis of rotation

9

 supply reels

10

 Shedding arrangement

11

 Drive for shedding device

20

 Weft insertion device

21

 Clamping and cutting device

22

 Drive for gripper

23

 gripper head

24

 gripper bar

25

 heald

29

 pivot point

30

 off device

31

 Drive for take-off roller

32

 off roll

33

 axis of rotation

34

 deflecting

35

 Drive for tissue clamp

36

 tissue clamp

37

 deflecting

38

 reverse link

39

 forward link

40

 measuring device

41

 receiver

45

 evaluation

50

 control device

Claims (13)

Loom with - a shedding device ( 10 ) to form sheds ( 3 ) between a thread stock ( 9 ) withdrawn warp threads ( 1 ), - a weft insertion device ( 20 ) for the insertion of weft threads ( 2 ) in the form of tapes in the formed sheds ( 3 ), and - a trigger device ( 30 ) for removing the warp and weft threads ( 1 . 2 ) formed tissue ( 4 ) after a weft insertion, characterized by - a measuring device ( 40 ) for detecting geometric parameters, in particular the width, of a weft thread ( 2 ) before its entry into the formed shed ( 3 ), - by an evaluation device ( 45 ) for the evaluation of the recorded measurement results, and - by a with the trigger device ( 30 ) related control device ( 50 ) for controlling a movement of the tissue ( 4 ) including the deduction on the basis of the evaluated measurement results. Weaving machine according to claim 1, characterized in that the measuring device ( 10 ) is based on at least one of the following measuring methods: - an optical measuring method whereby the measuring device ( 10 ) is preferably in the form of a precision optical micrometer, and / or - an acoustic, in particular working by means of ultrasound, measuring method, and / or - a tactile measurement method. Weaving machine according to at least one of the preceding claims, characterized characterized in that the measuring device ( 40 ) is designed and set up to continuously increase the width of a weft thread ( 2 ) capture. Weaving machine according to at least one of the preceding claims, characterized in that the measuring device ( 40 ) is arranged such that it determines width values of the weft thread to be inserted next ( 2 ) or a weft thread ( 2 ) during its entry, whereby the measurement on the moving weft thread ( 2 ) is vornehmbar. Weaving machine according to at least one of the preceding claims, characterized in that the measuring device ( 40 ) on the entry side of the weft thread ( 2 ) is arranged. Weaving machine according to at least one of the preceding claims, characterized in that the evaluation device ( 45 ), the minimum width and / or the maximum width of a measured weft thread ( 2 ) to calculate. Weaving machine according to at least one of the preceding claims, characterized in that the evaluation device ( 45 ) is designed to produce a mixed value based on a plurality of measured values of a weft thread ( 2 ) or a weft thread ( 2 ) during its entry, in particular its mean width. Weaving machine according to at least one of the preceding claims, characterized in that the withdrawal device ( 30 ) a drivable take-off roll ( 32 ). Loom according to claim 8, characterized in that the withdrawal device ( 30 ) a pendulum drivable deflection roller ( 34 ), in the course of the fabric between the shed ( 3 ) and the drivable take-off roll ( 32 ) is arranged Weaving machine according to at least one of the preceding claims, characterized in that the withdrawal device ( 30 ) a tissue clamp ( 36 ) and that the extraction device ( 30 ) from the control device ( 50 ) is controllable, that the tissue ( 4 ) together with the tissue clamp ( 36 ) by a predetermined, preferably on the basis of the evaluated measurement results determined route ( 38 ) is retracted against the weaving direction, preferably up to butt with the previously entered weft thread ( 2 ). Weaving machine according to at least one of the preceding claims, characterized in that by controlling the extraction device ( 30 ) the tissue ( 4 ) is placeable prior to the next weft insertion such that the weft thread ( 2 ) is enforceable in one of the following ways: - over its entire length without any gap formation with the trailing edge of the tissue ( 5 ), or - over its entire shot length with a distance to the tissue trailing edge ( 5 ), or - over its entire shot length, forming one or more gaps with the tissue trailing edge ( 5 ), under a regional concern at the tissue trailing edge ( 5 ) and / or overlapping with the tissue trailing edge ( 5 ). Weaving machine according to at least one of the preceding claims, characterized in that the evaluation device ( 45 ) and / or the control unit ( 50 ) are formed, at least the further weft insertion and the withdrawal device ( 30 ) stop when exceeding predetermined and / or falling below predetermined weft widths and / or output a predetermined signal. Weaving machine according to at least one of the preceding claims, characterized in that the evaluation device ( 45 ) is formed, errors of the weft thread to be entered ( 2 ), such as holes and / or splices, to recognize and trigger a predetermined action of the loom.

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