This application claims the priority of European Patent Application No. 05 026 813.5, filed on Dec. 8, 2005, the subject matter of which, in its entirety, is incorporated herein by reference.
The invention relates to a heddle, designed for the processing of warp threads, which are embodied in the form of bands.
Textiles are produced with weaving looms having at least one, as a rule many, weaving shafts for the shed forming. Each weaving shaft is a substantially rectangular frame, consisting of vertically arranged side supports, as well as an upper and a lower transverse bar, the so-called shaft bar. The shaft bars hold heddle support rails, which for the most part are elongated steel rails with a rectangular cross section. The steel rails are designed to hold the heddles. Each heddle is provided with end eyelets for threading it onto the upper and the lower steel rail. The heddle body extends between the end eyelets. A thread eyelet is provided approximately in the center through which the warp thread is guided. If the shaft bar is moved up or down, all warp threads extending through the thread eyelet of the heddles are moved out of the warp bundle, either up or down, so that a weaving shed is created.
French patent document FR 394 156 discloses a heddle of this type, which is fashioned from flat steel strip, wherein the flat sides of the steel strip are oriented in warp thread direction. For producing a thread eyelet, the heddle is compressed in this region, with holes punched in. The thread eyelet created in this way has a height, measured in vertical direction, which exceeds the width measured in horizontal direction, wherein the thread eyelet is oriented in warp thread movement direction.
German patent document DE-PS 22996 also discloses a heddle with a thread eyelet oriented in warp thread movement direction. The heddle consists of two thin layers of sheet metal, which are positioned parallel and one above the other. In the thread eyelet region, the sheet metal strips are curved away from each other, wherein the heddle is twisted in longitudinal direction, so that the thread eyelet is oriented transverse to the end eyelets.
The heddles presented herein are designed for processing essentially round threads. These days, however, the requirement of processing band-shaped fiber arrangements must increasingly be met. Frequently, band-shaped thread arrangements must be processed, which are composed of polyester, aramide, or carbon fibers and are used, for example, for producing textiles to reinforce high-stress composite structures, wherein it is frequently required that the band-shaped fiber arrangement retains the band shape during the weaving operation and is oriented, for example, parallel to the textile plane.
Based on this, it is the object of the present invention to provide a heddle that is suitable for the weaving of band-shaped warp threads.
The above is object is solved with the heddle according to claim 1, as well as with the heddle according to claim 2.
The heddle according to the invention, as defined in claim 1, is provided with a heddle body with thread eyelet, which is wider as seen in warp thread direction than it is high. Insofar, the shape of the thread eyelet is approximately adapted to the shape of the warp thread band or a corresponding warp thread group, which is here considered a warp thread. The width of the thread eyelet is larger by at least a few tenth of millimeters than the width of the band-shaped warp thread for which the respective heddle is intended. As a result, a flat band-shaped warp thread can run unhindered through the thread eyelet and is securely guided in the thread eyelet with little vertical play.
Regardless of this measure, it is advantageous according to claim 2 to provide the thread eyelet on the upper and the lower edge with a thread guiding surface that is rounded on the thread inlet and/or the thread outlet side, wherein the length of the thread guiding surface extending in warp thread direction exceeds the thickness of the heddle body to be measured in the same direction. The heddle body can be embodied relatively thin and can consist, for example, of sufficiently strong steel. The danger that sharp edges form as a result on the thread eyelet, which could damage sensitive threads, is prevented by the thread guiding surface according to the invention. The thickness of the heddle can thus be reduced to a minimum, which results in reducing the weight of the heddles and thus also the material costs while also achieving a higher operating speed.
The heddle is preferably twisted at least in the region of the thread eyelet, so as to be positioned transverse to the warp thread, meaning the flat sides of the heddle are positioned in a single plane that also contains the two heddle support rails, or at least encloses together with these an extremely. acute angle near 0°. As a result, it is achieved that the opening direction of the thread eyelet essentially coincides with the movement direction of the warp thread. The required opening width for the thread eyelet can consequently be kept to a minimum.
To form a shed, for example, a first weaving shaft is moved downward into the lowest position and a second weaving shaft is moved upward into the upper position. Both weaving shafts are provided with heddles according to the invention, with warp threads running through their thread eyelets. Following the movement of the first weaving shaft to the lower position and the second weaving shaft to the upper position, a warp thread of the first weaving shaft and a warp thread of the second weaving shaft jointly form a so-called weaving shed. The warp thread of the first weaving shaft extends through a thread eyelet on a heddle of the first weaving shaft in the lower region, wherein the warp thread of the second shaft runs through an eyelet on a heddle of the second weaving shaft in the upper region, thereby forming a weaving shed. Following the weft shot into this weaving shed, the two weaving shafts change their positions. The first weaving shaft moves upward while, at the same time, the second weaving shaft moves downward. Along with the weaving shafts, the heddles also change positions and thus also the warp threads or warp thread bundles running through the thread eyelets of the heddles. During this position change of the warp threads, the warp thread of the second weaving shaft slides by the outside edge of the adjacent heddle of the first weaving shaft. Conversely, the warp thread running through the thread eyelet of the first weaving shaft passes by the outside edge of the adjacent heddle of the second weaving shaft.
Since the thread eyelet of a heddle according to the invention is turned transverse to the warp thread, the region between the outside edge of the heddle and the thread eyelet can be embodied extremely small, thereby providing sufficient room for a warp thread band of an adjacent heddle of an adjacent weaving shaft during the position change, so that it can pass unhindered by the edge of the heddle of the adjacent weaving shaft. The danger of damaging warp threads during the position change is thus strongly reduced and tightly knitted textile materials can additionally be produced. For the same purpose of forming tightly knit textiles, the heddle body can be positioned at a slight angle in the region of the thread eyelet, wherein the opening angle of the thread eyelet is inclined at an acute angle of only a few degrees, relative to the plane mentioned in claim 3.
The heddle body preferably consists of a band-shaped material, e.g. a steel band, which can be oriented transverse to the warp thread, at least at the thread eyelet. The turning angle between thread eyelet and end eyelets is preferably 90°, which allows achieving the above described conditions and advantages.
The end eyelet can be embodied as separate element that is connected to the heddle body. However, it is preferably formed integrally with the heddle body, meaning it consists of the same material as the heddle body and transitions seamless and smoothly into this body. The heddle consequently can be produced as a simple stamped body. The end eyelet can optionally be O-shaped, C-shaped or J-shaped, or can have any form developed in the future.
It is also possible to produce the heddle without twisting from a flat material, wherein the end eyelets are formed with projections, which are attached to the heddle body and project over its flat side. The projections can take the form of tongues, for example, which are cut out of the heddle body and bent outward on the side. The projections can furthermore be elements that are attached later on to the flat side of the heddle body. Such elements can be attached by laser-welding, for example, or can also be riveted on in the form of sheet metal brackets, wherein the welding seams can extend either transverse to or in longitudinal direction of the heddle body. The version where the welding seam is oriented in longitudinal direction results in especially high stability for the end eyelet formed this way.
One preferred embodiment focuses special attention onto the design of the thread-guiding surfaces, wherein these can take the form of plates that are bent out of the thread eyelet. The freely projecting plates of one preferred embodiment are bent outward, thereby forming an angle of at least 110° to the thread eyelet. As a result, generously dimensioned thread-guiding surfaces are obtained, which can be used for weaving even brittle threads that are sensitive to breakage.
In particular for the processing of strongly adhering or abrasive threads, the thread-guiding surfaces are advantageously embodied on separate elements, which are connected to the heddle body, thus forming the upper and/or lower edge of the thread eyelet. The special elements can consist of hardened steel, hard alloy, plastic or ceramic material and can be connected to the heddle body by gluing, welding or soldering them on. The use of hard alloy or ceramic material permits the weaving of particularly aggressive bands, such as those composed of aramide fibers. The additional elements can furthermore be provided with sections, which protect at least a portion of the side edges of the thread eyelet. This can be achieved by embodying the elements as pins that are provided on the ends with disks or plates. It is furthermore advantageous if the heddle is provided in the region of the thread eyelet with a resistant material support, for example consisting of titanium nitride or a different type of mechanically resistant material. If hard alloy elements are used for forming the thread guiding surfaces, this support can be restricted to the hard alloy elements.
For an extremely cost-effective embodiment of the heddle according to the invention, the elements clearly project over the upper and lower edge of the thread eyelet. The elements are embodied as small lamina, which are arranged on the flat sides of the heddle body and have well-rounded edges. These lamina are attached to the flat sides on the front and the back of the heddle body and, based on their positioning, determine the height of the thread eyelet in longitudinal direction of the heddle. With this measure, thread eyelets of varying height can be realized on uniformly stamped out heddle bodies, so that the respective heddles can be equipped for different band-shaped warp threads.
Further details of advantageous embodiments of the invention are the subject matter of the drawing, the specification, or the claims.
Exemplary embodiments of the invention are illustrated in the drawing and show in:
a and 3b A modified embodiment of the thread eyelet of a heddle in a view from above, following the stamping out of the heddle (
a and 4b A modified embodiment of a thread eyelet with elements for determining thread guiding surfaces, shown in a view from above (
a and 5b A different embodiment of a thread eyelet with elements for forming thread guiding surfaces, showing a view from above (
a and 6b A thread eyelet with positively interlocking support elements for determining the thread guiding surface, in a view from above (
a and 7b A modified embodiment of the thread eyelet for a heddle, with elements embodied as lamina, for forming thread guiding surfaces, shown in a view from above (
a and 8b An embodiment of a heddle with widened thread support surface, shown in a view from above (
a and 9b A modified embodiment of the heddle with round thread-guiding elements in the thread eyelet, in a view from above (
a A thread guiding element for a heddle according to
b A thread guiding element for the heddle according to
The upper and the lower edge 10, 11 are preferably formed with the thread guiding surfaces 17, 18 which can directly adjoin the flat sides of the region 12, as shown in
The heddle 1 described so far operates as follows:
For the operation of a weaving loom and in order to form a weaving shed, several heddles 1 are lined up on the heddle support rails 2, 2′ of at least two weaving shafts, as shown for the embodiment in
According to a modified embodiment, the regions 12 of the heddles 1 are not precisely turned by 90° relative to the end eyelets 5, 6. The heddles 1 of the first and second weaving shaft thus can overlap somewhat, thereby making it possible to create a denser textile. For this embodiment, the clear width as seen from the warp thread 36 also exceeds at least slightly the width of the flat warp thread 36.
It is furthermore possible to embody the heddle 1 slightly asymmetrical, either by stamping in the openings for the end eyelets 5, 6 off center into the heddle body 3, or by bending the twisted regions and/or the turning regions 13, 14 in a somewhat asymmetrical manner.
It must be pointed out here that the heddle 1′, as well as all heddles 1′ described in the following, are provided with a thread eyelet 7 having a height H, which is lower than the width B. However, the heddles 1′ of these embodiments without exception can also be provided with eyelets 7, having a height H that exceeds the width B.
A different embodiment of the heddle 1′ is illustrated in
This embodiment is provided with the special feature of having thread guiding elements 24, 26 that edge the thread eyelet 7 on the top and on the bottom, thus forming an upper and lower edge. The thread guiding elements 24, 25 are embodied, for example, as cylinder-shaped pins, positioned inside corresponding recesses 26, 27 that are formed on the edges 10, 11, wherein these recesses can be ring-shaped. The thread elements 24, 25 preferably have a diameter that exceeds the thickness of the heddle body 3. The length of the thread guiding surfaces 17, 18, which are embodied on the thread guiding elements 24, 25, consequently exceeds the thickness of the heddle body 3.
The thread guiding elements 24, 25 are preferably embodied identical and can consist, as shown in
a, 5b illustrate a modified embodiment of the heddle 1′, wherein the thread guiding elements 24, 25 have a partial-cylindrical, preferably semi-round cross section. This shape considerably simplifies the positioning of the thread guiding element 24, 25 and the fastening of said element to the heddle body 3. Otherwise, the above description provided for the exemplary embodiment according to
a, 6b illustrates yet another modified embodiment of the heddle 1′. This embodiment comprises thread guiding elements 24, 25, which have a basic cylindrical shape and are each provided on the sides facing away from the thread eyelet 7 with a groove for accommodating the heddle body 3. In this way, the thread guiding elements 24, 25 can be attached easily and securely to the heddle body 3, wherein a material-to-material connection achieved through gluing, soldering, or welding is preferred. Otherwise, the above explanations apply.
a, 7b show a different embodiment of the heddle 1′ according to the invention. The special feature of the heddle body 3 for this heddle is that it is provided on its flat side 28 with thread guiding elements 24, 25 in the form of flat rods, which overlap the upper edge 10 and the lower edge 11 of the thread eyelet 7. The thread guiding surfaces 17, 18 formed by the rounded edges of the thread guiding elements 24, 25 consequently delimit the clear height H of the thread eyelet 7, wherein this clear height H is noticeably smaller than the distance measured in the same direction between the edges 10, 11. The area projecting over the edges 10, 11 of the thread guiding elements 24, 25 is preferably large enough to prevent the warp thread from coming into contact with the edges 10, 11, wherein this area of the thread guiding elements 24, 25 that projects over the edges 10, 11 is preferably large enough, so that the warp thread does not reach the edges 10, 11 even in the shed-forming position, meaning the position where the weaving shaft has reached the extreme upper or lower position.
As shown with
As shown, the thread guiding elements 24, 25 of the exemplary embodiment according to
a and 9b illustrate a different embodiment, which is based on the one shown in
The thread guiding elements 24, 25 of the aforementioned embodiments can also be embodied as cylindrical pins with buffer elements 29, 30 at the ends, wherein these buffer elements 29, 30, for example, can be disk-shaped sections having a diameter D1, D2 that exceeds the diameter D0 of the cylinder-shaped central section of the pin. The buffer elements 29, 30 can be provided with a flattened area on one side, designed to make it easier to attach the heddle body 3 to one of the flat sides 21, 28.
The embodiment of the end eyelet 5 as shown in
A heddle 1 for flat, band-shaped warp threads 36 is provided with a thread eyelet 7, having a width that is preferably wider than its height. A thread eyelet 7 of this type prevents a deformation of the band-shaped warp thread 36, in particular a pushing together of the sides during the shed formation. The heddle 1 according to the invention is furthermore preferably provided with thread guiding surfaces 17, 18, for which the length exceeds the thickness of the heddle 1 body 3, relative to the running direction of the warp thread 37. As a result of this measure, it is possible to reduce wear to the heddle 1 as well as the warp thread 36.
Number | Date | Country | Kind |
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05 026 813.5 | Dec 2005 | EP | regional |
05 026 818.4 | Dec 2005 | EP | regional |