Weaving Machine

Abstract

A weaving machine with a shedding arrangement (10, 25) for forming loom sheds (3) between warp threads (1) drawn off from a thread supply (9), a weft insertion arrangement (20) for inserting weft threads (2) in the form of tapes into the formed loom sheds (3), and a drawing-off arrangement (30) for drawing off the woven fabric (4) formed by warp and weft threads (1, 2) after a weft thread insertion. The weaving machine encompasses a measuring arrangement (40) for detecting geometric parameters, especially the width, of a weft thread (2) before its insertion in the loom shed (3), as well as an evaluating arrangement (45) for evaluating the detected measurement results. A control arrangement (50) for controlling a motion of the woven fabric (4), including the drawing-off, based on the evaluated measurement results, is present on the weaving machine and is connected with the drawing-off arrangement (30).

Claims

1. A weaving machine comprising: a shedding arrangement (10) for forming loom sheds (3) between warp threads (1) pulled off from a thread supply (9), a weft insertion arrangement (20) for inserting weft threads (2) in the form of tapes into the formed loom sheds (3), a drawing-off arrangement (30) for drawing-off the woven fabric (4) formed of warp and weft threads (1, 2) after a weft thread insertion, a measuring arrangement (40) for detecting geometric parameters, especially the width, of a weft thread (2) before its insertion into the formed loom shed (3), an evaluating arrangement (45) for evaluating the detected measurement results, and a control arrangement (50) connected with the drawing-off arrangement (30) for controlling a motion of the woven fabric (4) including the drawing-off based on the evaluated measurement results.

2. The weaving machine according to claim 1, characterized in that the measuring arrangement (10) is based on at least one of the following measuring methods: an optical measuring method, wherein the measuring arrangement (10) is preferably embodied in the form of an optical precision micrometer, and/or an acoustic measuring method, especially operating by means of ultrasound, and/or a tactile measuring method.

3. The weaving machine according to claim 1, characterized in that the measuring arrangement (40) is embodied and configured to continuously detect the width of a weft thread (2).

4. The weaving machine according to claim 1, characterized in that the measuring arrangement (40) is arranged in such a manner so that it is able to measure the width values of the weft thread (2) that is next to be inserted or of a weft thread (2) during its insertion, wherein the measurement can be carried out on the moving weft thread (2).

5. The weaving machine according to claim 1, characterized in that the measuring arrangement (40) is arranged on the insertion side of the weft thread (2).

6. The weaving machine according to claim 1, characterized in that the evaluating arrangement (45) is embodied to calculate the minimum width and/or the maximum width of a measured weft thread (2).

7. The weaving machine according to claim 1, characterized in that the evaluating arrangement (45) is embodied to calculate a mixed value on the basis of several measured values of a weft thread (2) to be inserted or of a weft thread (2) during its insertion, especially its width average value.

8. The weaving machine according to claim 1, characterized in that the drawing-off arrangement (30) encompasses a drivable drawing-off roll (32).

9. The weaving machine according to claim 8, characterized in that the drawing-off arrangement (30) further encompasses an oscillatingly or swingingly drivable deflecting roll (34) that is arranged in the fabric path between the loom shed (3) and the drivable drawing-off roll (32).

10. The weaving machine according to claim 1, characterized in that the drawing-off arrangement (30) comprises a fabric clamp (36), and in that the drawing-off arrangement (30) is actuatable in such a manner by the control arrangement (50) so that the woven fabric (4) together with the fabric clamp (36) is moved back contrary to the weaving direction by a prescribed path distance (38), which is preferably determined based on the evaluated measurement results, preferably until contacting against the previously inserted weft thread (2).

11. The weaving machine according to claim 1, characterized in that by controlling the drawing-off arrangement (30) the woven fabric (4) can be positioned before the next weft insertion in such a manner so that the weft thread (2) is insertable according to one of the following manners: over its entire weft length without any gap formation with the fabric rear edge (5), or over its entire weft length with a gap relative to the fabric rear edge (5), or over its entire weft length while forming one or more gaps with the fabric rear edge (5), and namely with area-wise contacting on the fabric rear edge (5) and/or overlapping with the fabric rear edge (5).

12. The weaving machine according to claim 1, characterized in that the evaluating arrangement (45) and/or the control arrangement (50) are embodied at least to stop the further weft insertion and the drawing-off arrangement (30) upon exceeding and/or falling below prescribed weft thread widths and/or to output a prescribed signal.

13. The weaving machine according to claim 1, characterized in that the evaluating arrangement (45) is embodied to recognize faults of the weft thread (2) to be inserted, for example holes and/or splices, and to trigger a prescribed action of the weaving machine.

Description

[0034] In the following the invention will be described in further detail in connection with an example embodiment. It is shown by:

[0035] FIG. 1 a schematic top plan view onto a weaving machine,

[0036] FIG. 2 a schematic view of the weaving machine according to FIG. 1 from the supply side of the warp threads,

[0037] FIG. 3 a schematic cross-section through the weaving machine according to FIGS. 1 and 2 with a view direction in the weft direction.

[0038] In FIGS. 1, 2 and 3, a weaving machine for warp and weft threads in the form of tapes is schematically illustrated. The tapes consist, for example, of carbon and/or glass fibers. Such a weaving machine is also termed a tape weaving machine. The embodiment of the weaving machine described here can alternatively also be used for such woven fabrics in which merely the weft threads are present in the form of tapes, while the warp threads are utilized in a typical thread form, preferably however in the form of coarse, that is to say thick and/or wide threads.

[0039] Several warp threads 1 running next to one another are provided in rotating supply bobbins 9 and are transported in the warp direction 6 (also named the machine direction or the weaving direction) to a shedding arrangement 10, 25. This encompasses heddles, which are not shown in further detail, and through which the warp threads 1 are threaded-through. The heddles are preferably inserted or combined together in heald frames 25schematically illustrated as framesand are alternately lifted or lowered with the aid of a drive 11, so that the warp threads 1 guided through the heddles form a loom shed 3 between themselves in a known way and manner. When one half of the warp threads 1 are deflected in their upper maximum position and the other half are deflected in their lower maximum position, a weft thread 2 can be guided through the thusly formed loom shed 3.

[0040] For supplying the weft thread 2, present as a tape, a supply bobbin or spool 7 rotating about a rotation axis 8 is provided, which supply bobbin 7 is located on one side of the weaving machine. The warp threads 1 can alternatively, instead of the supply bobbin 9, also be provided on a common supply arrangement, e.g. a warp beam.

[0041] For insertion of a weft thread 2 into a loom shed 3, a weft insertion arrangement or device 20 is provided, which encompasses a drive 22, a gripper rod or rapier 24 connected with the drive 22, and a gripper head 23 provided on the free end of the gripper rod 24. The gripper rod 24 is drivable by means of the drive 22 back and forth through the opened sheds 3. Instead of a gripper rod 24 it is alternatively also possible to use a gripper band or tape, which, however, under certain circumstances must be guided on its path through the loom shed.

[0042] Before the weft insertion, first the weft thread 2 that has been prepared or presented from the weft thread bobbin 7 is tightly held in the area of its free end by means of a clamping and cutting arrangement or device 21 that is only schematically illustrated, whereupon the gripper head 23 drives or moves through the loom shed 3 and grasps and clamps this free end of the weft thread 2. On its part, the clamping and cutting arrangement 21 lets go the free end of the weft thread 2, so that the gripper head 23 can pull the weft thread 2 through the loom shed 3. Then the loom shed 3 is closed in that the warp threads 1 are moved downwards or upwards respectively. Moreover, the clamping and cutting arrangement 21 clamps the weft thread 2 on the side of the weft thread bobbin 7 and separates the previously inserted weft thread 2 from the endless weft thread 2 supplied from the weft thread bobbin 7.

[0043] In FIG. 2, the loom shed 3 is schematically illustrated from the rear side of the weaving machine, which loom shed 3 is formed by warp threads 1 that are alternately moved up and down, so that weft thread 2 subsequently or followingly supplied from the weft thread bobbin 7 can be conveyed through the loom shed 3. For clamping and releasing, the clamping jaws of the gripper head 23 comprise a pivot point 29 that is only schematically indicated. Of course, purely linear motions of the clamping jaws of the gripper head 23 are also conceivable. Clamping and releasing of the clamping jaws can occur, for example, with the aid of a mechanical control arrangement that is arranged outside of the loom shed; however pneumatic or electro-mechanical control arrangements are also possible.

[0044] In an alternative that is not illustrated, the weft thread 2 is gripped by a gripper that is previously not driven or moved through the loom shed in the direction of the weft thread, but rather is arranged on the side of the weft thread bobbin, there grasps the weft thread end, transports it through the loom shed, lets go the weft thread, and then moves back in the direction of the weft thread bobbin without the weft thread.

[0045] The inserted weft thread 2 is still to be bound onto the woven fabric 4. For this purpose, before or during the closing of the loom shed 3, the fabric rear edge or the binding or interlacing point 5 with the woven fabric 4 is moved in the direction toward the inserted weft thread 2. For this, the woven fabric 4 over its entire width is pushed contrary to the warp direction 6 by a rearward or reverse path distance 38 to the previously inserted weft thread 2, until, for example, the fabric rear edge 5 lies in contact on the longitudinal edge of the said weft thread 2. Preferably in that regard, the woven fabric 4 is clamped by means of a fabric clamp 36 driven by a drive 35 (see FIGS. 1 and 3). Next, the clamping by the fabric clamp 36, which exists if applicable, is released, and this clamp is pushed or advanced still further contrary to the warp direction 6 so far that the fabric clamp 36 can also grasp and clamp the said weft thread 2. Next the fabric clamp 36 together with the clamped woven fabric 4 is moved in the warp direction 6 by the forward path distance 39 so that the next loom shed 3 can be formed.

[0046] The thereby constantly growing woven fabric 4 is rolled or wound up on a drawing-off roll 32 that is rotationally driven by a drive 31 about a rotation axis 33. In order to produce the forwards and backwards motion of the woven fabric 4, in the present example embodiment an oscillating or swinging motion of intermediately arranged deflecting rolls 34, 37 is realized in the warp thread path or course or in the woven fabric path or course. This oscillating or swinging motion of the deflecting rolls 34, 37 is presently realized actively with a reversing oscillating drive (not illustrated in the figures) that synchronously moves both deflecting rolls 34, 37.

[0047] The drawing-off roll 32 as well as the fabric clamp 36 and if applicable the deflecting roll 34 are part of a drawing-off arrangement or device 30, whereby the drives of these devices must be exactly adapted to one another. This is carried out by a control arrangement 50 (in this regard see below in connection with the explanation of the invention).

[0048] The deflecting roll 34 is arranged in the fabric path between the loom shed 3 and the drawing-off roll 32. The fabric clamp 36 is also located in this area, and is preferably arranged in the area of the fabric rear edge 5.

[0049] The optional deflecting roll 37 is arranged in the rear area or region of the weaving machine between the heald frames 25 and the supply bobbins 9.

[0050] In principle it is also possible to avoid an oscillating or swinging motion of the deflecting rolls 34 and 37, whereby then the forward and backward motion of the woven fabric 4 must be achieved by corresponding control of the drive 31 for the drawing-off roll 32. For the compensation in the rear area of the machine, then e.g. corresponding drives for the supply bobbins 9 would be required.

[0051] It has now been found that especially the width of the weft threads 2 fluctuates due to the production thereof, so that non-uniform fabric appearances arise with fixedly prescribed path distances 38 (for the reverse or reward motion) and 39 (for the subsequent forward motion), which is not desirable for all applications.

[0052] Therefore, according to the invention, a measuring arrangement 40 for detecting geometric parameters, especially the width, of the weft threads 2 before their insertion in the respective formed loom shed 3 is provided. In the present example embodiment, the measuring arrangement 40 is provided between the weft thread bobbin 7 and the clamping and cutting arrangement 21 below the weft thread 2.

[0053] The measuring arrangement 40 presently is based on an optical measuring principle and in this regard probes or scans the weft thread 2. For example the measuring arrangement 40 can be embodied as an optical precision micrometer. The optical signals reflected back from the weft thread 2 are received by the measuring arrangement 40. Alternatively or additionally, a receiver 41 (shown in dashed lines in FIG. 2) is arranged above the weft thread 2. In principle, measuring arrangements 40 for detecting geometric parameters of an elongated surfacially shaped structure, such as that of a tape, are known and do not need to be explained in further detail here.

[0054] The measurement values or measurement results detected by the measuring arrangement 40 are presently provided further to an evaluating arrangement or device 45, which evaluates the measurement results and provides the results of the evaluation (which are presently also referred to as evaluated measurement results) further to a control arrangement or device 50. The control arrangement 50 is connected with the drawing-off arrangement 30 and controls the motions of the woven fabric 4 in that it controls the oscillating or swinging back and forth motion of the deflecting rolls 34, 37 and if applicable of the fabric clamp 36 and also controls the winding or rolling up of the woven fabric 4 onto the drawing-off roll 32. In this regard, the control arrangement 50 is connected with the drive for the oscillating motion of the deflecting rolls 34, 37 and if applicable with the drive 35 that drives the fabric clamp 36, as well as also with the drive 31 that drives the drawing-off roll 32.

[0055] Generally it is noted that the signal and control lines in FIGS. 1 and 2 are illustrated with dash-dotted lines.

[0056] The measuring arrangement 40 is preferably embodied for the continuous measurement of the geometry of the weft thread 2. Thereby all deviations from the ideal form or shape (width, holes, lateral chipping or spalling) are reliably detected. In this regard, the measurement is preferably carried out when the weft thread 2 is guided past the measuring arrangement 40.

[0057] In this regard, the continuous measurement suitably also encompasses the measurement values of that section of the weft thread 2 located in the measurement area, which belongs to the weft thread 2 that is to be inserted next), while this is still clamped by the clamping and cutting arrangement 21. The measured values in this regard are preferably also taken into consideration by the evaluating arrangement 45, so that measured values are present over the entire length of the next to-be-inserted weft thread 2.

[0058] The evaluating arrangement 45 is preferably embodied in such a manner so that it is able to calculate the minimum width and/or the maximum width of the weft thread to be inserted. Alternatively or additionally, the evaluating arrangement 45 can calculate, for example, a mixed value based on several measured values of a weft thread 2, especially the width average value thereof.

[0059] Based on the evaluations of the evaluation arrangement 45, the drive of the deflecting rolls 34, 37 and if applicable the drive 35 of the fabric clamp 36 can be actuated by the control arrangement 50, in order to drive or move the woven fabric 4 back by an adapted path distance 38 contrary to the warp direction 6 based on the determined weft thread width (for example based on the determined extreme values relating to the weft thread width or a mixed value). The subsequent counter motion 39 of the woven fabric 4 in the warp direction 6 is also correspondingly adapted, so that the forward path distance 39 just like the rearward path distance 38 varies depending on the evaluation. Contrary to the prior art, thus no constant prescribed motions of the woven fabric 4 are provided after each weft insertion, but rather motions that are adapted to the actual width of the respective previously inserted weft thread. Also the winding or rolling-up of the woven fabric 4 onto the drawing-off roll 32 as well as the oscillating motion of the deflecting roll 34 between drawing-off roll 32 and fabric clamp 36 are controlled dependent on the actual current determined weft thread width.

[0060] The drives with which the various different motions of the previously described structural assemblies of the weaving machine are controlled are preferably embodied as individually actuatable motors or as motor-transmission combinations, which preferably receive their signals from the control arrangement 50. These drives are embodied so that theyas neededcarry out reversing pivoting, rotating or linear motions.

[0061] The control arrangement 50 can actuate the drawing-off arrangement 30, especially the deflecting roll 34 and the fabric clamp 36, in such a manner so that the woven fabric 4 is positioned in the most varied manner before the next weft insertion. For example in this regard it is possible that the woven fabric 4through continuous consideration of the width of the respective weft threads 2comprises no gaps. Alternatively, the woven fabric 4 is positioned before the respective next weft thread insertion in such a manner so that a spacing distance of each weft thread 2 relative to the fabric rear edge 5 is always present, so that a fabric appearance with gaps between successive weft threads 2 results. Corresponding to a further alternative, the drawing-off arrangement 30 is controlled in such a manner so that along the currently inserted weft thread 2 that fluctuates in its width, one or more gaps are formed with the fabric rear edge 5, whereby in the remaining areas this weft thread 2 contacts against the fabric rear edge 5 and/or even forms overlapping regions with the fabric rear edge 5.

[0062] Mixed forms of the abovementioned fabric appearances are also possible without difficulty through corresponding adjustment of the control arrangement 50.

[0063] The evaluating arrangement 45 and/or the control arrangement 50 are preferably embodied and configured in such a manner so as at least to stop the further weft insertion as well as the drawing-off arrangement 30 in the event of exceeding and/or falling below prescribed weft thread widths, and/or to output a prescribed signal. Similarly it is advantageous if the evaluating arrangement 45 can recognize faults of the weft thread 2 to be inserted, for example holes and/or splices, and can trigger a prescribed action of the weaving machine, especially via the control unit 50.

[0064] The present invention is not limited to the illustrated and described example embodiments. Derivations or modifications within the scope of the patent claims are also possible just like a combination of the features, even when these are illustrated and described in different example embodiments.

REFERENCE NUMBER LIST

[0065] 1 warp threads

[0066] 2 weft threads (tapes)

[0067] 3 loom shed

[0068] 4 woven fabric

[0069] 5 fabric rear edge

[0070] 6 warp thread direction

[0071] 7 weft thread bobbin

[0072] 8 rotation axis

[0073] 9 supply bobbins

[0074] 10 shedding arrangement

[0075] 11 drive for shedding arrangement

[0076] 20 weft insertion arrangement

[0077] 21 clamping and cutting arrangement

[0078] 22 drive for gripper

[0079] 23 gripper head

[0080] 24 gripper rod

[0081] 25 heald frame

[0082] 29 pivot point

[0083] 30 drawing-off arrangement

[0084] 31 drive for drawing-off roll

[0085] 32 drawing-off roll

[0086] 33 rotation axis

[0087] 34 deflecting roll

[0088] 35 drive for fabric clamp

[0089] 36 fabric clamp

[0090] 37 deflecting roll

[0091] 38 rearward path distance

[0092] 39 forward path distance

[0093] 40 measuring arrangement

[0094] 41 receiver

[0095] 45 evaluating arrangement

[0096] 50 control arrangement