Multiple Longitudinal Traversing Shed Weaving Apparatus

This application is related to my commonly assigned, copending U.S. application Ser. No. 096,776 filed Nov. 23, 1979, entitled "Multiple Longitudinal Traversing Shed Weaving Apparatus".

The present invention generally relates to the weaving art, and more specifically, relates to a new and improved construction of a so-called multiple longitudinal traversing shed weaving apparatus or loom, meaning a loom wherein a plurality of successive sheds are formed and retained to establish waves of sheds which travel longitudinally of the warp threads. Such type looms have also been referred to in the art as warp-wave looms, in order to distinguish the same from the type of loom using "weft waves" traveling transversely of the warp threads.

Generally speaking, the multiple longitudinal traversing shed weaving apparatus or loom of the present development is of the type comprising a weaving rotor which is provided with shed-retaining elements or members which retain the warp threads, throughout a predetermined path, in their upper shed position or lower shed position. Additionally, there is provided control means which, viewed in the direction of travel of the warp threads, is located forwardly of the weaving rotor and serves for the lateral deflection and allocation of each warp thread to a shed-retaining element which determines the upper shed or lower shed.

Multiple longitudinal traversing shed looms or warp-wave looms, as is known, form together with the so-called wave shed weaving machines, that species of multi-phase weaving machines or looms wherein there are continuously inserted a number of mutually stepwise shifted or staggered weft threads in likewise stepwise shifted and traveling sheds. While with the wave shed weaving machines or looms the sheds are simultaneously multiply formed over the width of the fabric and migrate in the weft direction, in the case of the multiple longitudinal traversing shed weaving looms there is formed, in each case, a shed over the entire fabric width and the successively formed sheds simultaneously move in the direction of the warp threads.

A first type of multiple longitudinal traversing shed weaving machine of the previously mentioned type has been proposed in U.S. Pat. No. 3,848,642 wherein the control means for the lateral deflection of the warp threads are constituted by rotatable control rolls which are provided at their outer surface with closed to-and-fro extending guide grooves positioned at an inclination with respect to the lengthwise axis of the control rolls and provided for each respective warp thread. During rotation of the control rolls the warp threads, in accordance with the course of the guide grooves, are laterally deflected, and thus, are allocated to the desired shed-retaining element. This allocation is augmented by separation elements which dip into the warp threads and are arranged, viewed in the direction of travel of the warp threads, directly after the control rolls.

With this multiple longitudinal traversing shed weaving machine a number of warp threads are allocated in each case with a single shed-retaining element. This leads to the result that the warp threads are relatively markedly deflected by the control rolls. The guiding of the warp threads in the guide grooves causes a pronounced loading of the warp threads, especially a pronounced friction between the warp threads and the guide grooves. Additionally, the control rolls are not variable and when changing over to a new fabric weave must be exchanged or at least restructured.

Hence, with the foregoing in mind it is a primary object of the present invention to provide a new and improved construction of multiple longitudinal traversing shed weaving apparatus which is not afflicted with the aforementioned drawbacks and limitations of the prior art constructions.

Another and more specific object of the present invention aims at providing a loom of the character described wherein the control means thereof only slightly load the warp threads, and additionally, the loom can be easily accommodated to changes in fabric weaves without having to modify or otherwise restructure the loom.

Yet a further significant object of the present invention aims at providing a new and improved construction of loom of the type described which is relatively simple in design, economical to manufacture, extremely reliable in operation, not readily subject to breakdown or malfunction and requires a minimum of maintenance and servicing.

Now in order to implement these and still further objects of the invention, which will become more readily apparent as the description proceeds, the loom of the present development is manifested by the features that the control means comprise elements whose stroke can be adjusted in the weft direction.

According to a preferred embodiment of the inventive multiple longitudinal traversing shed weaving apparatus the stroke-adjustable elements are formed by rods extending in the weft direction, these rods being provided with guide eyelets for the warp threads.

The inventive embodiment has the advantage that, on the one hand, between the guide eyelets and the warp threads there arise only very slight frictional forces and, on the other hand, by selecting a suitable actuation mechanism for the rods it is possible to produce any desired fabric weave or pattern, without having to modify or restructure or otherwise alter the control means.

The invention will be better understood and objects other than those set forth above, will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:

FIG. 1 is a schematic cross-sectional view through a multiple longitudinal traversing shed weaving apparatus or loom according to the invention;

FIG. 2 is a schematic view looking in the direction of the arrow II of the loom of FIG. 1;

FIG. 3 is a sectional view, on an enlarged scale, showing details of the arrangement of FIG. 2;

FIG. 4 is a cross-sectional view, taken substantially along the line IV--IV of FIG. 2;

FIG. 5 is a schematic perspective view of the weaving rotor of the loom illustrated in FIG. 1, certain of the parts thereof being shown in exploded illustration; and

FIG. 6 is a fragmentary cross-sectional view of the weaving rotor portrayed in FIG. 5.

Describing now the drawings, it is to be understood that to simplify the illustration thereof only enough of the construction of the loom has been shown to enable those versed in the art to readily understand the underlying principles and concepts of the invention. Turning attention now to FIGS. 1 and 2 the multiple longitudinal traversing shed weaving loom disclosed therein will be seen to essentially comprise a warp beam 1, a back rest or beam 2, a control device or means 3 for the lateral deflection of the warp threads 4, in order to allocate such, in accordance with a predetermined fabric or cloth pattern, to an upper shed position or lower shed position. Additionally, there is provided a weaving rotor 5, a breast beam 6, a take-off device or mechanism 7 for the woven fabric or cloth 8 and a cloth beam 9.

The weaving rotor 5, rotating during operation in the direction indicated by the arrow P, is of substantially roll or cylindrical configuration and is provided at its circumference, viewed in the direction of rotation P, alternately with lamellae or leaf reeds or combs 10 and 11 extending in the lengthwise direction of the weaving rotor 5, and thus, in the weft laying or insertion direction. The lamellae reeds or combs 10 consist of beat-up lamellae or leaf members 12 serving for beating the inserted weft threads. The lamellae reeds or combs 11 consist of guide lamellae or leaf members 13 between which there are alternately arranged the shed-retaining elements 14 and 15 which determine the upper shed position or lower shed position, respectively, of the warp threads 4. By means of the shed-retaining or holding elements 14 and 15 the warp threads 4 are retained, over the entire wrap angle .alpha. of approximately 120.degree., in their upper shed position or lower shed position. The thus formed sheds successively travel towards the fell of the fabric or cloth, and in the time where the sheds are open there is inserted in a step-wise mutually offset fashion to one another into each shed a weft thread.

Adjacent one of the end faces of the weaving rotor 5 there is arranged a unit or device 16 for preparing and inserting the weft threads. This device 16 does not constitute subject matter of the invention and therefore need not here be further considered. It is however mentioned that any suitable weft insertion system can be used in conjunction with the weaving rotor 5, whether such be a weft insertion system working with shuttles, gripper shuttles, projectiles, to-and-fro moving rods or tapes or with a fluid medium. Such type conventional weft insertion systems, used in conjunction with multiple longitudinal traversing shed weaving looms have been disclosed in German Pat. No. 1,089,695 and in each of U.S. Pat. Nos. 2,742,058, 3,848,642, 4,122,871, 4,122,872 and 4,129,153, to which reference may be readily had and the disclosure of which is incorporated herein by reference.

Continuing, by reverting to FIG. 2 it will be apparent that along the outer shell or surface of the weaving rotor 5, on the one hand, the beat-up lamellae or elements 12 of the lamellae reeds 10 are in alignment with one another and, on the other hand, the guide lamellae or elements 13 of the lamellae reeds 11 are in alignment with one another, and that the lines of alignment of the individual guide lamellae or elements 13 extend in the center of the intermediate space, the so-called tube, of the related beat-up lamellae or elements 12, and the lines of alignment of the beat-up lamellae or elements 12 extend in the center of the tube of the related guide lamellae or elements 13. Also it will be additionally seen that the shed-retaining elements 14 are in alignment with one another and equally the shed-retaining elements 15 are in alignment with one another.

The control device or control means 3 comprises a number of, for instance, as shown four rods or bars 17, arranged parallel to the weft insertion direction. The rods 17 are connected with an actuation device 18 and can be moved to-and-fro thereby in the direction of the double-headed arrow A. The rods 17 are equipped with conventional guide eyelets, merely schematically indicated by reference character 90 in FIG. 2, for the warp threads 4, so that the latter, during movement of the rods 17 in their lengthwise direction, are laterally deflected. The number of rods 17 depends upon the nature of the fabric pattern which is to be woven, and in the case of linen weaves it is sufficient to use two such rods 17, while with more complicated patterns or fabric weaves there must be employed a corresponding greater number of such rods or bars 17. The actuation device 18 is in the nature of a conventional control mechanism for dobby looms, such as typified by U.S. Pat. No. 3,171,445, granted Mar. 2, 1965 and U.S. Pat. No. 4,154,268, granted May 15, 1979, to which reference may be had and the disclosure of which is incorporated herein by reference, which, in accordance with a predetermined program, moves each of the rods 17, corresponding to a conventional harness or harness frame, into one of both end positions prior to each dipping of one of both lamellae reeds 10 or 11 into the warp threads 4. In such terminal or end position the related warp thread 4 is located within its tube at the left or at the right of the lamellae or elements 12 or 13, as the case may be, which bounds such tube, and therefore, owing to the displacement through one-half of the tube pitch between the successive lamellae reeds 10 and 11, will be positively leased or drawn into the correct tube of the next lamellae reed.

The difference between the control device 3 and a conventional shed forming mechanism by means of a dobby loom and harnesses or harness frame resides essentially in three points worthy of enumeration:

(1) The mass of a rod 17 is appreciably less than that of each conventionally known harness or harness frame, so that for the displacement thereof quite considerably less energy is required in relation to a harness frame.

(2) The dimensions of a rod 17 are appreciably smaller than that of each known harness frame, so that within the same space there can be accommodated quite a larger number of rods 17.

(3) The displacement path, in other words the stroke of the rod 17 only amounts to a fraction of a normal harness stroke, since such displacement path is not dependent upon the shed opening, rather only must cause pivoting or deflection of a warp thread from the one to the other bounding lamella or element of a tube. Therefore, the displacement of the rod 17 can be accomplished in a considerably shorter amount of time than the displacement of a conventional harness frame and the frequency of the displacements of the rod 17, in comparison to the frequency of the stroke movements of conventional harness frames which, already at the present time, limit the output of single-phase high production looms, can be increased by a multiple.

Now based upon the showing of FIG. 3 there will be explained in greater detail the leasing or drawing-in of the warp threads 4 in the weaving rotor 5. In such FIG. 3 there have been schematically illustrated two lamellae reeds 11.sub.1 and 11.sub.2 having the guide lamellae or elements 13 as well as the lamellae reed 10 extending therebetween and equipped with the beat-up lamellae or elements 12. The warp threads 4, shown by a double line, located in each case in the upper shed position in the lamellae reed 11.sub.1 which has dipped already for some time into the warp threads, are guided by the rods 17.sub.1. On the other hand, the warp threads 4, shown with a single line, are located in the lamellae reed 11.sub.1 in each case in the lower shed position and are guided by the rods 17.sub.2. As already stated, for reasons of clarity in illustration both of the other rods 17, shown in FIG. 1, have been omitted, so that in the lamellae reed 10 each second tube does not have any warp thread 4 and in the lamella reed 11 each tube only has one warp thread 4.

It is assumed that the lamellae reed 10 as well as the lamellae reed 11.sub.1 have completely dipped into the warp threads 4 and that the lamellae reed 11.sub.2 will shortly dip into the warp threads 4, and the warp threads 4 guided by the rods 17.sub.1 should reach the lower shed position and the warp threads 4 guided by the rods 17.sub.2 should reach the upper shed position.

To achieve this result the rods 17.sub.1 and 17.sub.2 must be moved by the actuation device 18 (FIG. 2) in such a manner that the warp threads 4, guided by such rods, must assume the position illustrated in full lines. The warp threads 4 guided by the rod 17.sub.1 are thus moved towards the left and the warp threads 4 guided by the rod 17.sub.2 are moved towards the right, until they bear at the beat-up lamellae 12 which bound thereto at the left and right, respectively. In this way the guide lamellae or elements 13 can enter in each case between two spread apart warp threads 4 into the sheet of warp threads. Furthermore, the one of these two spread apart warp threads 4 always arrives into a tube of the lamellae reed 11.sub.2 equipped with a shed-retaining element 14 for the upper shed position and the other warp thread arrives in a tube of the lamellae reed 11.sub.2 having a shed-retaining element 15 for the lower shed position.

If the warp threads 4 in the lamellae reed 11.sub.2, guided by the rod 17.sub.1, should arrive at the upper shed position and the warp threads 4, guided by the rod 17.sub.2, should arrive at the lower shed position, then the rod 17.sub.1 must be moved in the direction of the arrow B and the rod 17.sub.2 in the direction of the arrow C, so that the warp threads 4 assume the broken line and chain-dot line positions, respectively.

The displacement path of the rods 17.sub.1 and 17.sub.2 between both of the warp thread positions, appears in FIG. 3, owing to the scale and the exaggerated large shown thickness of the lamellae or elements 12 and 13 and equally because of the exaggeratedly large shown tube width in the lamellae reeds 10 and 11, appreciably larger than in reality. In fact, this displacement path amounts to only a few millimeters and, as a general rule, is clearly below 10 millimeters.

Now in FIGS. 4 to 6 the weaving rotor 5 has been illustrated in detail. Such weaving rotor 5 will be seen to comprise, in the embodiment under discussion, a substantially tubular-shaped roll 20 which is connected with a drive shaft 21. The roll 20 is provided at its outer surface or shell with a multiplicity of grooves 22 and 23 extending essentially parallel to the lengthwise axis of the rotor 5, and therefore, essentially parallel to the weft insertion direction. These grooves or slots 22 and 23 serve for receiving the lamellae reeds 10 and 11, respectively. The grooves 22 and 23 have a substantially L-shaped cross-sectional configuration. In each case two grooves 22 and 23 form a related pair, wherein the transverse legs of the L-shaped configured or profiled grooves 22 and 23 are directed away from one another, as best seen by referring to FIG. 5. The outer surface or shell of the roll 20 is provided with, for instance, a total of fourteen such pairs of grooves 22 and 23.

Due to this construction of the weaving rotor 5 composed of the roll or cylinder 20 with the peripheral grooves 22 and 23, it is possible to dispense with the use of the shed-holding elements 15 (FIG. 3) for the lower shed position, since support of the warp threads 4, in such lower shed position, as best seen by referring to FIG. 4, can be accomplished by the outer surface of the roll or roller 20. The individual lamellae reeds 10 and 11, instead of being provided with shed-retaining or holding elements 15, (FIG. 3) for the lower shed position, here are equipped with spacer elements 24, as best seen by referring to FIGS. 5 and 6, which at most slightly protrude past the outer surface of the roll 20.

From the showing of FIGS. 4 and 6 it will be apparent that both the guide lamellae or leaves 13 as well as also the shed-retaining elements 14 for the upper shed position of the warp threads 4 are provided with a recess 19. These recesses 19 form for each lamella reed 11 a channel for the weft insertion. Additionally, it will be apparent that each two respective guide lamellae or elements 13 alternately bound a shed-retaining element 14 for the upper shed position of the warp threads 4 and a spacer element 24, respectively, and that each two beat-up lamellae 12 likewise bound a space element 24.

Continuing, as best seen by referring to FIG. 4 the beat-up lamellae or elements 12 of the neighboring lamellae reed in each case are in alignment with the center of the tube of the lamellae reed formed by the guide lamellae or elements 13. As clearly shown in the illustration there is located in each tube of each of both lamellae reeds 10 and 11 two warp threads 4, in the tube between two guide lamellae or elements 13 there are conjointly located both of the warp threads 4 either in the upper shed position or in the lower shed position, and in the tube between two beat-up lamellae 12 there is located in each case a warp thread 4 in the upper shed position and the other warp thread is located in the lower shed position. This illustration corresponds to the use, indicated in FIG. 1, of four rods 17. On the other hand, in FIGS. 2 and 3 there have been shown for sake of clarity in illustration only two rods 17. Hence, each second tube is empty between the beat-up lamellae 12. It is here further still mentioned that the arrangement of the warp threads 4, illustrated in FIG. 4, corresponding to a double stitch linen weave, is random and that with the illustrated weaving rotor 5 together with the control device 3 it is possible to realize all conceivable cloth pattern variations between both of the extreme values, namely: all of the warp threads in the upper shed position or all of the warp threads in the lower shed position.

Each lamella reed 11 is formed of shed-retaining elements 14 for the upper shed position, guide lamellae or elements 13 and spacer elements 24. The lamellae reeds 10 are constructed from spacer elements 24 and beat-up lamellae or elements 12. As best seen by referring to FIG. 5, the shed-retaining elements 14 and the spacer elements 24 are appreciably thicker or wider than the beat-up and guide lamellae 10 and 13, respectively. Preferably, the thickness of the shed-retaining elements 14 arranged between the lamellae or leaves or equivalent structure of the one lamellae reed 11 or 10 and/or the spacer elements 24 amount to three times the thickness of the lamellae of the other lamellae reed 11 and 10, as the case may be.

The individual elements of each lamella reed 10 and 11 are for instance connected by a suitable adhesive so as to form reed portions of, for instance, 100 mm length and these reed portions are inserted into the corresponding grooves 22 or 23 and fixed therein. Upon changing the lamellae density it is possible to simply exchange the individual lamellae reeds 10 or 11, without having to dismantle the entire weaving rotor 5.

The individual elements forming the lamellae reeds 10 and 11 each have a base portion, whose cross-section is accommodated to that of the grooves 22 and 23. The spacer or distance elements 24 are dimensioned such that they do not or only slightly protrude, by means of their upper end, past the outer surface of the roll or cylinder 20. The shed-retaining elements 14 for the upper shed position, the beat-up lamellae or elements 12 and the guide lamellae or elements 13 possess, following their base portion, a respective upper portion 25, 26 or 27 protruding past the outer surface of the roll 20.

The upper portion 25 of the shed-retaining elements 14 for the upper shed position has the shape of a finger which is curved opposite to the direction of rotation P of the weaving rotor 5, whose outer curved surface forms the support for the warp threads 4 in their upper shed position and whose inner curved surface, viewed from the front, bounds the guide channel 19 for the weft insertion from the top and from the front in the direction of rotation P. At its lower region the guide channel 19 is bounded by the outer surface or shell of the roller cylinder 20, towards the rear by the beat-up elements 12 of the neighboring lamellae reed 10.

The upper portion 27 of the guide lamellae 13 has the configuration of a parallelogram-shaped vane, which is provided at its edge confronting the roll or cylinder 20 with a contour or shape corresponding to the inner curvature surface of the finger-shaped upper portion 25 of the shed-retaining elements 14 for the upper shed position, this contour equally bounding the channel 19, from the top and from the front.

The upper portion 26 of the beat-up lamellae 12 has a sickle-like configuration. The tip of the sickle is directed rearwardly opposite to the direction of rotation P of the weaving rotor 5. The outer edge of this upper portion 26 serves for beating the inserted weft threads, and therefore, protrudes from all of the aforementioned upper portions furthest in radial direction away from the outer surface of the roll 20. The outer edge of the upper portion or part 27 of the guide lamellae 13 is located somewhat closer to the roll 20 and the outer curvature surface of the finger-shaped upper portion or part 25 is located somewhat below one-half of the distance between the outer surface of the roll 20 and the outer edge of the upper portion 26 of the beat-up lamellae 12 which beats the laid weft threads.

As best seen by referring to FIG. 6, the configuration and dimensions of the lamellae or elements 12 and 13 and the mutual spacing of the grooves 22 and 23, and therefore, that of the lamellae reeds 10 and 11, is chosen such that between the individual lamellae reeds there is only a small spacing amounting to about 1 mm or less.

Of course, the weaving rotor 5, instead of being structured in the described manner, also could be formed in the manner of a conventional rotational or rotary reed, as is known from the wave shed loom art, of individual lamellae in the form of circular plates provided with projections. This type of weaving rotor must, however, practically be completely dismantled, knocked-down, re-assembled and again installed, whenever there is a change in the article which is being fabricated at the loom.

While there are shown and described present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto, but may be otherwise variously embodied and practised within the scope of the following claims. Accordingly,