US3346017A

US3346017A - Method and apparatus for resuming weaving

Info

Publication number: US3346017A
Application number: US446265A
Authority: US
Inventors: Fend Heinrich
Original assignee: Oerlikon Buehrle Holding AG
Current assignee: OC Oerlikon Corp AG Pfaeffikon
Priority date: 1964-04-14
Filing date: 1965-04-07
Publication date: 1967-10-10
Anticipated expiration: 1984-10-10
Also published as: ES312200A1; CH416489A; NL6504142A; SE317331B; GB1108735A; AT269761B; BE662504A; DE1535562B1

Description

Oct. 10,1967

' H. FEN D METHOD AND APPARATUS FOR RESUMING WEAVING Filed April 7, 1965 6 Sheets-Sheet 1 Oct. 10,1967

H. FEND METHOD AND APPARATUS FOR RESUMING WEAVING '6 Sheets-Sheet 2 Q Filed April 7, 1965 a 7,. v .1. i k wflwh L N 1 Jk fiw h |r TLIIPAELM PIILHIPIFII il an H PIPITIVX HHWE M H P T QH Oct. 10,1967 H. FEND I METHOD AND APPARATUS FOR RESUMING WEAVING Filed April '7, 1965 6 Sheets-Sheet 5 II lllll Oct. 10,1967 H. FEND METHOD AND APPARATUS FOR RESUMING WEAVING Filed April 7, 1965 6 Sheets-Sheet 4 Ada 0t.1o,1967 H.FEND 3,346,017-

METHOD AND APPARATUS FOR'RESUMING WEAVING Filed April '2, 1965 e Sheets-Sheet 5 26 120 I 17 122 121 27 l I Q 7:3 25

. 12 I v 10 O I Oct. 10,1967 H .FEND 3,346,017

METHOD AND APPARATUS FOR RESUMING WEAVING Filed April 7, 1965 e Sheets-sheaf e.

United States Patent O fiice 3,346,01 Patented Get. 10, 1967 3,346,017 METHOD AND APPARATUS FOR RESUMING WEAVING Heinrich Fend, Uster, Zurich, Switzerland, assignor to Oerlikon-Buhrle Holding AG, Zurich, Switzerland Filed Apr. 7, 1965, Ser. No. 446,265 Claims priority, application Switzerland, Apr. 14, 1964, 4,805/64 33 Claims. (Cl. 139-12) The present invention has reference to an improved method for continuing weaving of a fabric in the process of being manufactured at a wave weaving loom after interruption of the weaving operation as well as relating to an improved apparatus for a wave weaving loom for enabling performance of the aforesaid method.

With so-called wave weaving looms a plurality of shuttles successively following one another carry a respective weft thread between the warp threads through a respective travelling shed formed in each instance by the Warp threads over only a portion of the width of the fabric. This weft thread iscontinuously beaten by beat-up elements up to the fell of the already produced fabric before the warp threads at the relevant location of the fabric width are brought into position for receipt of the next weft thread.

When a weft thread has been completely inserted throughout its entire length it has also already been beaten to the fabric over a large portion of its length, and further weft threads have also been inserted over a portion of their length by the following shuttles and have been beaten. The geometric location of the beat-up location of the weft thread which in each case was the last to be inserted, hereinafter conveniently referred to as the beat-up line, thus forms an angle, even if a small one, with the direction of the weft. If the weft threads should extend at right angles to the warp threads as in the case with fabrics produced at conventional looms, then the beat-up line must form an angle with the direction of warp which differs somewhat from 90. This angle is different in accordance with the compactness or density of the weft threads, the fabric width and the number of simultaneously working shuttles. On the other band, should the beat-up line always form a right angle with the direction of the warp then the weft threads are beaten at an angle to the warp threads which differs from 90, and the fabric must thereafter be somewhat stretched or deformed in order that the angle between the weft threads and warp threads becomes 90.

This condition in both cases has the disadvantage that it is not merely possible to simply continue weaving, if perhaps for the removal of the weaving error the loom is shut down and the last completely or partially inserted weft threads removed from the fabric. Then, namely, at

the location of the removed threads no new threads are inserted and beaten. Hence, in the fabric there remains a gap which extends in the direction of the weft and makes the fabric unusable. On the other hand, if the warp is pulled back in its entirely to such an extent that the first newly inserted weft thread at the shuttle entrance side is beaten at the location of the last-removed weft thread then the beat-up members would forwardly displace and compact together the last non-removed weft threads to a degree which increases towards the shuttle outlet side, whereas the newly inserted weft thread extends rearwardly at an inclination from this beat-up line and likewise once again leaves a gap.

Accordingly, the present invention concerns itself with an improved method for continuing weaving of a fabric in the process of being manufactured at a wave weaving loom after interruptions of the weaving operation wherein already inserted weft threads have been removed from the fabric, and whereby the previously mentioned disadvantages are effectively overcome.

Another considerable object of this invention is concerned with an improved method of resuming weaving at a wave weaving loom such that no gaps appear in the fabric.

A further object of the invention is a method wherein when the loom is shut down the weft thread last inserted before the weft defect is brought into coincidence with the beat-up line, and that after starting up the loom and while the next weft thread is being inserted forming a spacing between said beat-up line and said weft thread last inserted such that each subsequently inserted weft thread is beaten up parallel to the previously inserted weft thread.

Another object of the invention is a method in accordance with the previous object wherein said spacing increases from the shuttle outlet side to the shuttle inlet side of the fabric.

It is basically possible to bring about the mentioned coincidence and increase in spacing in two different Ways.

First of all, the warp threads in the region of the beat-up line can be displaced rearwardly and forwardly through different lengths, and secondly, it is possible to adjust the forward movement reversal points of the to-and-fro moving beat-up elements forming the beat-up line and acting upon the weft thread.

The first of both of these measures can be advantageously employed when the beat-up line and the direction of travel of the shuttles is at right angles to the direction of the warp and the weft threads after beating form an angle with the direction of the warp which differs from and there should take place a mutual displacement of the warp threads between the beat-up line and the cloth beam in order that the weft threads, when the fabric travels onto the cloth beam, come to lie at right angles to the direction of the warp.

For rearwardly and forwardly displacing the warp threads in the region of the beat-up line through different paths, it is possible to differently increase or shorten the length of the portion of the warp threads located between the warp beam and the beat-up line and simultaneously correspondingly shorten or lengthen the length of the warp thread portions contained in the fabric between the beat-up line and the cloth beam, without thereby changing the total length of the portions of the warp threads between the warp beam and the cloth beam. For this purpose, for example, it is possible to oppositely pivot the shafts of a deflecting roller disposed between warp beam and beat-up line and a deflecting roller disposed between beat-up line and cloth beam, such deflecting rollers extending transversely across the warp and the fabric, respectively, and the respective shafts of which are pivotally mounted at the same side of the warp and the fabric.

The second measure, namely, displacing the forward movement reversal points of the beat-up members particularly comes into consideration if the weft threads are to be beaten such that they then directly extend at right angles to the warp threads. Then, namely, the angle between warp threads and beat-up line must be change.- able in accordance with the compactness or density of the weft and the shuttle spacing.

In so doing, the beat-up members or elements can either move back and forth in planes disposed vertical to the beat-up line and forming a small angle with the plane of the warp threads. This could be achieved in that an apparatus which incorporates the beat-up elements and means for actuating the same and pivotally mounted at the one side of the warp thread chain and the fabric is pivoted in its entirety. Such an apparatus could also encompass the means and for guiding and displacing the shuttles, so that the direction of travel of the shuttles can also be changed with the direction of the beat-up line. This manner of adjusting or displacing the beat-up line pre-supposes that the mutual spacing of neighboring warp thread planes for the to-and-fro movement of the beat-up elements with the required stroke under the mentioned angle to these warp thread planes is suflicient, or that it is permissible for the beat-up elements in their rearmost terminal stroke position in each case to somewhat push to the side an associated warp thread.

However, it is more advantageous if the individual beat-up or heating elements move to-and-fro upon ways or tracks which extend along planes parallel to the warp threads. In such case, the beat-up line can be adjusted in that the range of stroke of the beat-up elements upon these tracks can be differently adjusted or displaced, perhaps in that the point of rotation where the beat-up elements are mounted are displaced through different paths parallel to the mentioned planes.

Now, it is also to be understood that a further important object of the present invention concerns itself with an improved apparatus for a wave weaving loom capable of carrying out the inventive method.

In accordance with the teachings of the present invention the inventive apparatus comprises a warp beam, means for building the sheds, means for inserting weft threads and beating of the weft threads, as well as a cloth beam. According to an important aspect of the invention, such apparatus further incorporates means for bringing about relative displacement between the beatup line of the weft thread beating means and the warp threads passing therethrough, such relative displacement increasing from the shuttle exit side to the shuttle inlet side. The means for bringing about the mentioned relative displacement could be such for variably lengthwise displacing the sections of the individual warp threads located in the region of the mentioned beat-up line, or could be such for displacing the one movement reversal points of the to-and-fro moving beat-up elements of the weft thread beating mechanism forming the beat-up line. In the latter case, the beating mechanism, if desired including the associated shuttle drive mechanism, could be pivotally mounted as a unit at one side of the weaving zone or field, or the range of stroke of the individual beating or beat-up elements can be variably displaceable along the paths or tracks of these beat-up elements.

Other features, objects and advantages of the invention will become apparent by reference to the following detailed description and drawings in which:

FIGURE 1 is a perspective view from the left side of a first w-ave weaving loom equipped with an embodiment of the aforementioned apparatus;

FIGURE 2 schematically illustrates in plan view the condition of the warp and the fabric at a wave weaving loom according to FIGURE 1 after rupture of a warp thread and shutting down of the loom;

FIGURE 3 is a view analogous to FIGURE 2 of the condition of the warp and the fabric after the adjustment or displacement thereof directly prior to continuing weav- 111g;

FIGURES 4 "and 5 depict in an analogous representation the same elements in two different stages after beginning of the renewed weaving operation;

FIGURE 6 is a perspective view from the right side of a wave weaving loom equipped with another embodiment of the mentioned apparatus;

FIGURE 7 is a schematic side view of a wave weaving loom equipped with a third embodiment of inventive apparatus;

FIGURE 8 is a schematic side View depicting details of the elements of the shuttle drive mechanism and beating mechanism of a wave weaving loom equipped with a fourth embodiment of inventive apparatus;

FIGURE 9 is a bottom view of a portion of the elements illustrated in FIGURE 8;

FIGURE 10 is a cross-sectional view of the device of FIGURE 9 taken along the line XX thereof; and

FIGURE 11 schematically illustrates the mode of operation of the wave weaving loom equipped with the apparatus depicted in FIGURES 8-10, and viewed from the top along the line XI-XI of FIGURE 8.

Describing now the drawings, in FIGURE 1 reference numeral 10 designates the warp beam of the illustrated wave weaving loom and reference numeral 12 the cloth beam upon which is wound the fabric 13 produced by means of the warp 11. It will be understood that the warp 11 travels from the warp beam 10 over a tension beam 14, a first deflecting roller 15 and a guide roller 16 to a group of harnesses schematically indicated at 17, and from this location moves to the beat-up line or location 18.

It will further be appreciated that the harnesses of the harness group 17 for reasons of convenience in illustration have not been depicted in the drawing, yet any known harness construction suitable for the purposes of the invention can be employed. These harnesses build from the warp 11, in that they alternately deflect their threads upwardly and downwardly, successive wave-shaped travelling sheds 19 which follow one another over the width of the fabric and are disposed between the warp threads 11a deflected upwardly and the warp threads 1111 which are deflected downwardly. A plurality of sheds are simultaneously formed, each shed traversing the fabric in a wave-like manner.

In each such travelling shed, one of which is schematically illustrated in lengthwise section at the forward edge of the warp 11, there moves a shuttle 21. The shuttles 21 are driven by members 22 which in the lengthwise direction of the loom, that is, along a respective plane extending vertical to the axes of the Warp beam 10 and the cloth beam 12, are individually moved back and forth in the same cycles with such a mutual phase displacement that they form in the direction of the arrow 23 transverse to the warp 11 and over the width of the fabric travelling bulges or loops of the same form and accommodated to the form of the shuttles 21, and in which these shuttles are held and entrained. In the region of each passing shuttle 21 each of the members 22 temporarily acts as shuttle drive means 22a (FIGURE 2). Between these regions these same members 22 also function as beating or beat-up means 22b in that they beat-up a weft thread 24 which has been inserted in its shed 19 by the latter-most shuttle 21 moving past the relevant member 22 up to the beat-up line 18 at the already woven fabric 13. In this case, the beat-up line 18 extends parallel to the axes of the warp beam 10 and the cloth beam 12.

It is here mentioned that the specific physical structure of the members 22 is not important for understanding the underlying teachings of the present invention, and such members are known to the art. For instance, they can be constructed as taught in my co-pending United States application, Ser. No. 294,971 and filed July 15, 1963, now US. Patent No. 3,255,782.

Continuing, each weft thread is then finally-depending upon the pattern of the fabric-tied into the resulting fabric 13 due to crossing of the

warp threads

11a and 11b at the relevant location by means of the corresponding harnesses of the harness group 17.

It will further be appreciated that the fabric 13 travels from the beat-up line 18 over a second guide roller 25, a second deflecting roller 26 and between an indexing and breast beam 27. This indexing and breast beam 27 is driven in appropriate manner at an angular velocity which is adjustable by means of a handwheel 48 and ensures for a uniform feed movement of the fabric 13 throughout its entire width. Fabric 13 moves from the breast beam 27 past a cont-act or pressure roller 28 onto the cloth beam 12 where it is wound-up. During operation of the loom the Warp 11 is continuously moved from the warp beam 10 to the beat-up line 18 and from this location moves as part of the fabric 13 to the cloth beam 12. The tensioning beam 14, both of the

guide rollers

16 and 25 and the breast beam 27 are mounted by shafts in both of the con fronting and spaced

side walls

29 and 30 of the loom frame such as to be parallel and non-displaceable with respect to one another and to the respective shafts of the warp beam and the cloth beam 12. Considering the right wall 29, as viewed from the cloth beam 12, only two support shoulders or

projections

29a and 29b are depicted, and from the left wall 30 portions have been removed in order to expose elements located behind such portions.

On the other hand, both of the deflecting rollers and 26 are pivotally mounted at their respective right end in the support shoulders 29a and 2%, respectively, of the right-hand side wall. The respective left end of these deflecting rollers 26 are displaceably retained in arcshaped slots 31 and 32, respectively, of the left-hand side wall 30. The lengthwise contour or profile of these slots 31 and 32 are selected such that the respective left ends of the deflecting rollers 15 and 26 can not only be displaced upwardly and downwardly rather also forwardly and rearwardly. Specifically, this displacement can be carried out in such a manner that the forces at these rollers 15, 26 and brought about by the tension of the warp 11 and the fabric 13 exhibit components which are as small as possible and extend parallel to the axis of the relevant roller. Consequently, there is counteracted against lateral deviation of the warp 11 and the fabric 13.

The deflecting roller 26 is mounted at such a height in the shoulder or projection 29b that it just cont-acts the plane of the fabric moving from the guide roller to the breast beam 27 when the axis of the deflecting roller 26 is situated in parallelism with the axes of the guide roller 25 and the breast beam 27. This happens when the deflecting roller 26 contacts against the upper end of the slot 32. When the left end of the deflecting roller 26 is moved downwardly, then the path of the warp 11 from the beatup line 18 to the breast beam 27 and the cloth beam 12 lengthens. In other words, the individual warp threads 11 upon downward pivoting of the deflecting roller 26 are displaced forwardly in the region of the beat-up line 18 through different amounts which increase from the right to the left. When the weft threads 24 of that portion of the fabric which bears upon the breast beam 27 or is wound onto the cloth beam 12 travel parallel to the axes of these beams and are situated at a right angle to the warp threads 11, then in the region of the beat-up line or fell 18 the weft thread 24 which was the last to be inserted into the fabric forms a small angle with the beat-up line 18 which is that much larger the further down the left end of the deflecting roller is located in the slot 32.

In order to compensate for this dilferent displacement of the warp threads 11 in the region of the beat-up line 18 without changing the mutual position of warp beam 10 and cloth beam 12, without changing the length of the warp threads between both beams and without changing the warp thread tension, the deflecting roller 15 during downward pivoting of the deflecting roller 26 is upwardly pivoted about its support location in the support shoulder or projection 29a in such a manner that the path of each warp thread 11 from the tension beam 14 to the guide roller 15 is shortened exactly the same amount as the path of the same warp thread 11 is lengthened from the guide roller 25 to the breast beam 27. To this end, the left end of the rear deflecting roller 15 in the slot 31 and the left end of the forward deflecting roller 26 in the'slot 32 are oppositely displaced by means of a common control lever 38 through the agency of a respective control link or rod 33 and 34 articulated to the aforesaid common lever 38 by means of a pin 35 and 36 respectively. Apart from the foregoing physical structure, it will also be recognized that a tension spring 39 engages with the forward end 38a of the lever 38, the opposite end of this spring 39 being suspended at a bolt 40 seated in the wall 30. This tension spring 39 strives to rock the lever 38 counterclockwise, thus to lower the left end of the deflect ing roller 15 and to raise the left end of the deflecting roller 26. i

The position of the common control lever 38 is determined by a second lever 41 through the intermediary of a control link or rod 42 coupling both aforesaid levers 38 and 41. The lever 41 is mounted at a pin 43 which is seated at a regulating or adjusting slide member 45 horizontally displaceably guided upon two stationary pins 44 engaging in slot means 44a of slide member 45. The pin 43 in turn engages with a lengthwise slot 46 of the lever 41. The adjustment slide member 45 possesses a rack or toothed construction 47 at its forward end 47a with which engages a pinion 49. This pinion 49 is operably connected for rotation with the handwheel 48 serving to regulate the angular velocity of the breast beam 27 and thereby the feed velocity of the warp threads 11 and the fabric 13. Assuming that the handwheel 48 is rotated in clockwise direction corresponding to an increase of the feed velocity, then the slide member 45 together with the pin 43 is displaced horizontally to the left.

The movement of the levers 38 and 41 and thus of both deflecting rollers 15 and 26 is controlled by means of a slide 50. This slide 50 is articulated by means of a bolt 51 to the lever 41, is vertically displaceable in a stationary guide 52 arranged at the loom frame and engages by means of a pin 53 in a cam groove or slot 54 of a gear 55. Gear 55 is freely rotatable upon a stub shaft 56 or the like mounted at the wall 30. The slide member 50 can be locked in the region of its uppermost position by means of a pawl lever 57 carrying a pin 59 engaging beneath a nose 58 of the slide member 50. The pawl 57 is pivotally mounted upon a pin 60 seated at the wall 30. A spring 61 is suspended at one end at a bolt 62 seated at the wall 30 and engages at its other end by means of a bolt 63 with the pawl lever 57 to pull such towards the slide member 50. Bolt member 63 also serves the purpose of rocking this slide member 50 by hand in order to release the pin 59 from engagement with the slider nose 58.

Now, the gear 55 is drivable by means of a gear 64 maintained in rotation by the non-illustrated loom drive in the direction of the arrow 64a. Gear 64 completes for each loom cycle one complete rotation, that is, rotates once during the time of passage of a shuttle at a considered location till the passage of the next shuttle at this location. Moreover, the transmission ratio from gear 64 to gear 55 corresponds to the reciprocal value of the number of shuttles 21 appearing across the fabric width. In the present exemplary situation where four shuttles successively follow one another across the width of the fabric such transmission ratio amounts to 1:4. It will also be observed that the gear 55 exhibits a smooth or non-toothed recess 65 in which can rotate the continuously revolving gear 64 without entraining gear 55.

Forwardly of the location 66 of the cam groove 54 where the pin 53 engages with this groove when the slide member 50 is located in its lowermostposition and up to the location 67 of such groove where such pin 53 is located at the uppermost position of the slide member 50, this groove ascends in spiral-like manner contra the direction of rotation 55a of the gear 55, whereas it steeply descends from location 67 to location 66.

There will now hereinafter be described the mode of operation ofthe considered exemplary embodiment of apparatus while making reference to FIGURES 2 to 5. Here again, in these last mentioned figures the warp threads are designated by reference character 11 and the Weft threads by reference character 14. Numeral 17 schematically designates the harnesses serving for shed formation, and reference numeral 22 designates the previously mentioned elements or members which act as shuttle drive means 22a for the shuttles 21 as well as beat-up means 22b effective behind each shuttle for the weft thread 24 emanating from the shuttles. Reference character 18 represents the beat-up line, that is the line up to which the members 22 functioning as beat-up means 221) forwardly displace the inserted weft thread 24 in order to beat up such to the already woven fabric 13.

Assuming that the forward deflecting roller 26 is located in its uppermost pivotal position where it just still contacts the fabric 13 and its axis is parallel to the axis of the breast beam 27 and parallel to the beat-up line 18, then, if the fabric 13 is not stretched, the weft threads 24 in the region of the beat-up line 18 must travel parallel to those of the fabric 13 wound onto the cloth beam 12 and, therefore, if such are to be located at right angles to the warp thread 11, extend parallel to the beat up line 18 (see FIGURE 3).

However, since in each moment a plurality of weft threads 24 at each respective point of the fabric width are inserted by a respective shuttle 21 and at each loca tion the last inserted weft thread is beat-up to the line 18, whereas the previously inserted weft thread is already further forwardly located in the fabric 13 during the normal weaving operation, the weft threads 24 in the region of the beat-up line 18 must form a small angle a (FIGURE 2) with such beat-up line 18 which opens towards the shuttle inlet side at the left. This angle (it differs in accordance with the number of shuttles 21 which are simultaneously located within the width of the fabric and depending upon the density or compactness of the weft thread. For example, with a fabric width of 2160 millimeters, a shuttle spacing of 240 millimeters (in other words, 9 shuttles across the fabric width) and a density or compactness of 10 weft threads per centi meter, the value of c amounts to about 0.25

In FIGURE 2 reference character 24a signifies a weft thread which has ruptured at location A and for which reason only half of it has been inserted in the fabric, whereas reference character 242 denotes the previously last completely inserted weft thread. In order to remove the weaving error resulting from rupture of the weft thread 24a it is initially necessary to remove from the fabric all of the following threads 24b to 24h which have been inserted after and behind this ruptured weft thread 24a as well as the ruptured weft thread 24a itself, the right half of which is missing. Also the thread must be removed from the shuttles 21 which are located within the fabric width.

If now weaving were simply to be continued, and as already explained, then the beginning of the first newly introduced weft thread, designated by reference character 241', upon beating by the members 22 acting as heatup means 2217, would come to lie directly behind the location at which was located the beginning of the rearmost previously removed weft thread 24h. As a result, an open gap would appear between the parallel weft threads 24z and 241', such, naturally, is unacceptable.

This fault could also not be corrected if the warp threads 11 are pulled back by rotating the warp beam 10, the breast beam 27 and the cloth beam 12 until the last already inserted weft thread 24z arrives at the location of the last-removed weft thread 24h. This is so because then this weft thread 24z and those weft threads inserted prior to it would come to rest in a mass increasing towards the right behind the beat-up line 18 and the beat-up means 22b effective along such line 18 could only compact the already produced fabric 13 such that the weft thread 24z pulled back to the location of the weft thread 24h at the beat-up line 18 and the previously inserted threads behind this beat-up line are pushed back. Upon further weaving there again appears a gap due to advancing of the warp threads 11 taking place along the beat-up line 18 and simultaneously with the insertion of the thread 241'. However, in this case the gap is of triangular form with a width which increases towards the right.

The previously mentioned defect can also not be removed if the warp threads 11 are only pulled back to such an extent until the weft thread 24z comes to lie at the location of the last completely inserted and now removed thread 24d. Indeed, there would then be prevented a displacement of this thread 24z and the threads lying in front of it during heating along the line 18, however, there would not be provided the connection of the new fabric to the already present fabric available at the left fabric edge. Once again, a gap Without weft threads would remain between the threads 24z and 2 1i which are parallel in this case.

It is now to be appreciated that these defects can be overcome by means of the loom depicted in FIGURE 1. During proper weaving the left end of the deflecting roller 26 is located in the lower position of the slot 32 appearing in FIGURE 1. If now, and as depicted in FIG- URE 2 and previously discussed, the weft thread 24a. is ruptured at location A, and if this thread 24a as well as all subsequently inserted weft threads 24b to 24h are removed from the fabric and the shuttles 21 located within the fabric width are emptied, then the pawl lever 57 is pivoted to the left by means of the bolt 63 and its pin 59 is released from engagement with the nose 58 of the slide member 50. Such renders it possible for the spring 39 to upwardly displace the forward ends 38a and 41a of the levers 3'8 and 41 respectively. The left end of the deflecting roller 26 then moves upwardly in the slot 32 until reaching its upper end so that the axis of this deflecting roller is parallel to the axis of the breast beam 27. On the other hand, the left end of the deflecting roller roller 15 moves downwardly in the slot 31. The path of each warp thread 11 between the warp beam 10 and the tension beam 14 and the guide roller 16 is thus increased, whereas the path between the guide roller 25 and the breast beam 27 and the cloth beam 12 is shortened by the same amount. This amount increases across the fabric width from the right to the left. The section of each warp thread located between the

guide rollers

16 and 25 in the zone of which there is disposed the beat-up line 18 is thus rearwardly displaced through a path increasing from the right to the left. It will be appreciated that the increase of such displacement from the right to the left of the fabric edge is not exactly linear so that each weft thread follows a slight arc, however, the deviation from the straight line is unimportant. The displacement is calculated such that by virtue of it the original inclined position of the weft threads 24 in the region of the beat-up line 18 is practically removed and the chord of the arc which these weft threads follow is now located at right angles to the warp threads 11. The last inserted, non-removed weft thread 24z is now brought into coincidence with the beat-up line 18, as shown in FIGURE 3, due to rotating the warp beam 10 and the cloth beam 12 and thus uniformly displacing all warp threads 11. Thereafter, the loom is placed into operation; however, the drive of the indexing and breast beam 27 as well as the cloth beam 12, in other words the uniform feed of the fabric 13 and all warp threads 11, still remain switched-out or disengaged.

Prior to releasing the slide member 50 the pin 53 is located in the steep portion of the cam groove or curve 54 of the gear 55 exactly beneath its position corresponding to the uppermost position of the slide member 50, since the gear 55 in this embodiment is not in engagement with the drive gear 64 on account of the recess 65. After releasing the slide member 50 the pivoting of the lever 41 brought about by the spring 39 and the downward movement of the slide member 50 due to the course of the cam groove or curve 54 causes rotation of the gear 55 in the direction of the arrow 55a until its teeth bounding the recess 65 come into engagement with the drive gear 64, which turns continuously during operation of the loom. If the loom is put back into operation after having been shut down, the drive gear 64 is again driven, causing the gear 55 to rotate in the direction of the arrow 55a. During this rotation the cam groove 54 upwardly displace the pin 53 and thereby the slide member 50 until its nose 58 releases the path for the pin 59 and the pawl lever 57 returns under the action of the spring 61 into its locking position depicted in FIGURE 1. This is the case when the highest position 67 of the cam curve 54 has approximately arrived at the pin 53. The slide member 50 upon further rotation of the gear 55 is raised somewhat further and after the pin 53 has passed the highest location 67 of the cam curve 54 member 50 is again lowered somewhat. At this moment the drive of the gear 55 by the drive gear 64 is interrupted because the recess 65 is then situated opposite the aforesaid drive gear 64. Since the pin 53 now engages in the steeply descending portion between locations 67 and 66 of the cam curve 54 the gear 55 is further rotated by the downwardly moving slide member 50 which is under the action of the spring 39 until its nose 58 comes to bear at the pin member 59. Then the recess 65 is located opposite the drive gear 64 such that it is completely out of engagement with the gear 55.

In some doing, the gear 55 has executed a complete rotation and the drive gear 64 as many rotations as shuttles 21 follow one another across the fabric width. In the illustrated embodiment such would then be equal to four revolutions. In this time, the levers 41 and 38 as well as the deflecting rollers 15 and 26 have been pivoted back into their starting position due to the gradual raising of the slide member 50 into its original locking position. Consequently, the path of the warp threads 11 from the warp beam 10 to the beat-up line 18 has shortened by an amount increasing from the right to the left, and the path of these warp threads 11 from the beat-up line 18 to the cloth beam 12 has increased by the same amount, so that these warp threads haveexperienced in the region of the beat-up line 18 a feed movement which increases from the right to the left by this amount. The already inserted weft threads 24, the last one of which was the thread 24z, have thus slowly again reached their original inclined position according to FIGURE 2. At the same time, that shuttle 21 which upon placing of the loom into operation has begun to insert a new weft thread 24i at the left edge of the fabric width directly behind the beat-up line 18 and behind the rearwardly displaced weft thread 24z, has pulled this weft thread 24i over the full fabric width. Its position at this moment with respect to the beat-up line 18 corresponds to that of the weft thread 240? of FIGURE 2. By inspecting FIGURE 4 there can be seen the position of this weft thread 241 which is in the process of being inserted and at the moment in' which the shuttle 21 delivering such thread has passed through somewhat more than the spacing between two'successively following shuttles and the already inserted weft threads up to and including the thread 242: have again received approximately more than a quarter of their original inclined position due to th different forward displacement of the warp threads 11. Consequently, at the left edge of the fabric and in front of the beat-up line 18 there is provided additional space for the just begun insertion of a further weft thread 24k.

FIGURE schematically illustrates the stage of the weaving operation in which the shuttles 21 inserting the Weft threads 24i' and 24k have moved further through a shuttle division and the already inserted weft threads have again assumed a further quarter of their original inclined position. The introduction of a third weft thread 24l has already begun.

In a subsequent stage ofthe weavingoperation which is not illustrated in the drawing the

weft threads

241', 24k and 241 would be inserted approximately to such an extent as the weft threads 24e, 24 and 24g appearing in FIGURE 2, and the inclined position of the weft threads of the fabric would already correspond approximately to that shown in FIGURE 2. The insertion of a fourth weft thread, which would be designated by reference character 24m, would have begun in the same manner as the thread 2411 of FIGURE 2.

After the weft thread 241' has once been completely inserted and the deflecting rollers 15, 26 have completely returned into their original positions, the drive for the HP dexing and breast beam 27 as well as the cloth beam are switched-in and the loom continues to operate without any adjustment. The breast beam is driven, for example, by an electrical connection (not shown) to the loom drive. A switch (not shown), operated by the lever 57, for example, serves to switch the breast beam into and out of operation. The adjustment of the regulating slide member 45 during rotation of the handwheel 48 for the purpose f changing the feed velocity of the fabric effects that the operation of the loom during the described work cycles i adjusted to the density of the weft threads changed in ac cordance with the feed.

The pin 43 at which the lever member 41 is mounted, is arranged at such a height at the regulating slide member 45 that the slot 46 of the lever 41 is horizontally disposed at such time as the slide member 50 is located in its lowermost position, that is, its pin 53 engages at location 66 of the cam curve 54. If such is the case, then the left end of the deflecting roller 26 is located in its uppermost position, the axis of this roller is parallel to that of the breast beam 27, and the warp threads 11 and weft threads 24 are located in the position depicted in FIGURE 3. This condition of the loom is independent of the feed velocity since in this case the horizontal displacement of the pin 43 during rotation of the handwheel 48 has no influence upon the likewise horizontal position of the lever 41.

If the velocity of the fabric 13 is increased by rotating the handwheel 48 in clockwise direction then the pin 43 travels to the left within the slot 46. Consequently, the spacing between the pins 43 and 51 decreases and the angle increases through which the lever 41 pivots about a constant path during the upward movement of the slide member 50 brought about by rotation of the gear 55. Also the angle through which the lever 38 and thus the deflecting rollers 15 and 26 are pivoted during upward movement of the slide member 50 correspondingly increase. The angle on which the weft threads 24 form with the beatup line 18 after locking of the slide member 50 by the pawl lever 57, that is during normal operation of the loom, increases in proportion as the feed velocity of the warp 11 and of the fabric 13 increases with respect to the constant velocity of the shuttles 21. The proportional increase in the angle is necessary, and is apparent from FIG. 2.

The loom depicted in FIGURE 6 differs from that of FIGURE 1 insofar as the guide and deflecting

rollers

15, 16, 25 and 26 ,are missing between the tension beam 70 and the beat-up line 18 as well as between the latter and the breast beam 71. The axes of the warp beam 10, a guide roller 72 arranged between the latter and the tension beam 70, the controller or indexing roller 73 which in this case is different from the breast beam 71 and its contact or pressure roller 28 as well as the cloth beam 12 are parallel to one another.

The tension beam 70 is mounted at its left end in an upper shoulder or projection 30a of the only partially visible left side wall 30 of the loom, and at its right end is mounted in a support or carrier 74 extending over the entire length of the loom and mounted to be horizontally displaceable in lengthwise direction. Likewise, the breast beam 71 is mounted in an upper projection or shoulder 30b of the left side wall 30 as well as in the carrier or support 74. Support 74 is displaceably guided upon two bolts or pins 75 which are mounted to the right side wall 29 of the loom frame which is only partially visible in FIGURE 6. Thus, the tension beam 70 and the breast beam 71 are pivotal in a horizontal plane, however, remain parallel to one another.

During normal operations of the loom the position of the support 74 is such that the axes of the tension beam 70 and the breast beam 71 are parallel to the beat-up line 18 and to the axes of the warp beam 10, the indexing roller 73 and the cloth beam 12. Since, during this operat ing condition, as explained with respect to FIGURES 1 and 2, the weft threads 24, of necessity, form a small angle on with the beat-up line 18, due to the parallelism of the beat-up line 18, the breast beam 71 and the cloth beam 12, the weft threads 24 of the fabric 13 wound onto the cloth beam 12 are not at right angles to the warp threads 11, rather build together with such an angle which deviates from a right angle by the amount a. Since 06 as a general rule only amounts to a small fraction of a radian, this deviation can be tolerated.

The displaceable support 74 possesses a recess 76 into which engages a pawl 78 pivotally mounted at a pin 77 at the side wall 29 at such time as the tension beam 70 and the breast beam 71 are located in parallelism to the warp beam and the cloth beam 12, as such is required by normal operation. A tension spring 79 connected at one end to a bolt or pin 80 arranged at the pawl 78 and at the other end to a pin 81 mounted at the frame side wall 29 maintains the pawl 78 in engagement with the recess 76 of the support 74. However, the pawl 78 can be manually released out of the aforementioned engagement contra the force of the spring 79. A tension spring 83 engages further rearwardly at a bolt 82 seated at the support 74. This tension spring 83 is suspended at a pin 84 of the frame wall 29 and strives to pull the support 74 forwards. Finally, a control lever 87 is pivotally mounted by means of a pin 86 to the carrier or support 74 for displacement of the latter. It will be seen that this control lever 87 P sesses a lengthwise slot 88 by means of which it can be pivotally mounted upon a pin 89 which can be displaced in vertical direction.

A pin 90 is located at the lower end of the lever 87, engaging with a cam curve or groove 91 of a cam disk 93 connected with a gear 92. The cam groove 91 exhibits a short radial section 94 the inner end of which is connected with the outer end via a spiral-shaped section 95 which gradually ascends in clockwise direction. A cutout or notch 96 is formed at the circumference of the cam disk 93 in which, during the rotational position of the cam disk 93 where the pin 90 of the lever 87 is located in the radial section 94 of the cam groove 91, there engages a stop lever 98 pivotally mounted upon a pin 97 at the frame wall 29. This stop lever 98 is under the action of a tension spring 99 suspended at a bolt 100 of the frame wall 29. Additionally, the cam disk 93 carries a pin 101 which, with the same rotational position of this disk, serves as a stop for a pawl 102. Pawl 102 is articulated by means of a pin 103 to a lever 104. Lever 104 is pivotally mounted upon a bolt 105 arranged at the frame wall 29. The pawl 102 is pulled forwardly and pressed against the pin 101 by means of a spring 107 suspended at a bolt 106 mounted to the wall 29. Reference character 108 represents a boss of the frame wall 29 by means of which the lever 104 is held in spaced relation from the surface of the wall 29. The pawl 102 possesses a shoulder 109 at its rear portion by means of which it can engage with the pin 101. However, the lever 104 is held in the position depicted in the drawing where the shoulder 109 is located further rearwardly than the pin 101 by means of an arm 110 extending forwardly from the control lever '87.

The gear 92 carrying the cam disk 93 is mounted to be freely rotatable upon a shaft or pin 111 arranged at the frame wall 29 and can be driven by means of a drive gear 112 which continuously revolves in clockwise direction during operation of the loom. The gear 92 is driven in counterclockwise direction and with a speed of rotation ratio which corresponds to the reciprocal value of the number of shuttles 21 which are simultaneously moving with the fabric width. The gear 92 and the cam disk 93 thus undertake one complete revolution during the time that a shuttle 21 passes across the full fabric width. In the rotational position of the gear 92 depicted in FIGURE 6 the teeth of the drive gear 112 in the meantime engage in a recess 113 interrupting the tooth structure of the gear '92 and provided at the circumference of the aforesaid gear 92 so that such cannot be driven. A cam disk 114 having a recess 115 is connected with the drive gear 112. A roller 116 mounted to the upper end of the lever 104 travels at the circumference of this cam disk 114 when lever 104 is not rocked forwardly by the arm 110.

In order to displace the pin 89 upon which the control lever 87 is pivotable there is provided a handwheel 48, just as was the case for the displacement of the pin 43 of the first embodiment. By means of the handwheel 48 it is possible to change the feed velocity of the warp threads 11 and the fabric 13 in relation to the speed of movement of the shuttles 21. By rotating this handwheel 48 in clockwise direction, for instance, the so-called feed velocity is increased and at the same time an adjustment or regulating lever 45 guided upon two bolts 44 and which exhibits a toothed structure 47 meshing with a pinion 49 and carrying the pin 89, is downwardly displaced by means of the pinion 49 rigidly connected for rotation with the handwheel 48. Due to the downward displacement of the pin 89 and with unchanged stroke of the pin engaging in the cam groove 91 the angle of deflection of the control lever 87, the displacement path of the support 74 and the angle through which the tension beam 70 and the breast beam 71 are pivoted with respect to the warp beam 10, the cloth beam 12 and the beat-up line 18 are increased in accordance with the mentioned feed velocity.

In order to explain the mode of operation of this embodiment of weaving loom, reference can again be made to FIGURES 2 to 5. It is only to be taken into consideration that during normal operation of the loom the tension beam 70 and the breast beam 71 are located parallel to the beat-up line 18 and the weft threads of the fabric 13 also during winding onto the cloth beam 12 still exhibit the same inclined position through the angle a as depicted in FIGURE 2.

If a weft thread 24a during insertion becomes ruptured at the location A (FIGURE 2), then in accordance with the embodiment of FIGURE 6 after shutting down of the loom the pawl 78 is advantageously initially released manually by means of the bolt '80 from engagement with the recess 76 of the support or carrier 74. The spring 83 then pulls the support 74 forwards, whereby the tension roller and the breast beam 71 pivot or rock forward about their support or bearing positions in the projections 30a and 30b respectively. Thus, the warp threads 11 in the region of the beat-up line 18 are pulled forwardly through a path which increases from the left to the right and places the already completely or partially inserted weft threads from the breast beam 71 up to and including the weft thread 24h parallel to the beat-up line 18.

The displacement of the support 74 is thus limited to the path necessary for this parallel positioning with the momentary weft density so that the pin 90 at the lower end of the control lever 87, which is pivoted in counterclockwise direction by the support 74 by means of the pin 86 about the adjustable pin 89, reaches the inner end of the radial section 94 of the cam groove 91. Due to this forward pulling of the warp threads through a path which increases from the left to the right, there appears between the weft threads 24d to 24h which were the last to be inserted and at each location of the fabric width and the beat-up line 18 a spacing which increases from the left to the right.

Thereafter, the ruptured weft thread 24a and the subsequently inserted weft threads 24b to 24h are removed from the fabric, which in contrast to the first embodiment is possible in many cases on account of the mentioned spacing between the last web threads 24d to 24h without further uniform displacement of the warp threads 11 towards the front. Also, the thread is removed from all shuttles 21 located within the confines of the fabric width. Then, the last weft thread 242: located in paral- 13 lelism to the beat-up line 18 and which has remained in the fabric 13 is brought into coincidence with the beat-up line 18 by turning back the warp beam and the cloth beam 12, so that the condition depicted in FIGURE 3 is attained.

During such time as the pin 90 moves inwardly in the radial section of the cam groove 91 the arm 110 of the control lever 87 follows such. As a result, the lever 104 can now rotate in clockwise direction under the action of the spring 107 elfective upon the pawl 102, whereby it entrains such pawl towards the left so that its shoulder 109 comes into engagement with the pin 101 of the cam disk 103. At the same time the roller 116 mounted to the upper end of the lever 104 comes into contact with the cam disk 114, specifically engaging in the recess 115 which confronts its during this operating condition.

Now, the loom, this time including the drive of the indexing beam 73 and thus the warp feed, is again placed into operation and the drive gear 112 begins to rotate in clockwise direction. Since the depression or recess 115 of the cam disk 114 associated therewith leaves the roller 116 the lever 104 is rocked in counterclockwise direction and the pawl 102 articulated thereto is displaced to the right. Due to engagement of its shoulder 109 with the pin 101 the cam disk 93 and the gear 92 connected therewith is rotated in counterclockwise direction, so that the toothing of this gear behind the recess 113 comes into engagement with the drive gear 112. This then takes over the drive of the gear 92 and the cam disk 93, by virtue of the rotation of which the stop lever 98 is pressed to the side.

The gear 92 then undertakes a complete revolution during such time as full shuttles 21 enter, one after the other, between the warp threads 11. During this rotation of the gear 92 the pin 90 engaging in the ascending section or' portion 95 of the cam grove 91 is gradually pressed towards the left. Consequently, the control lever 87 rotates in clockwise direction about the pin 89 and displaces the support or carrier '74 towards the rear against the force ofthe spring 83, so that the axes of the tension beam 70 and the breast beam 71 are gradually pivoted back about their bearing supports in the frame projections 30a and 30b into their normal operating position parallel to the beat-up line 18 and to the axes of the warp beam 10 and the cloth beam 12.

Due to this pivotal movement there is made amends for the feed or advance of the outermost weft thread at the right (viewed from the cloth beam), such feed being effected by the rotation of the indexing roller 73, so that such weft thread does not experience any displacement. On the other hand, the outermost warp thread left is practically not effected by such pivoting of the beams 70 and 71 since it is situated in the closest region of the point of turning of their axes, and its feed movement due to the indexing roller remains without reduction. The remaining warp threads experience a feed movement relative to the beat-up line 18 which variably increases from the right (shuttle exit side) to the left (shuttle inlet side). The resulting displacement of the warp threads 11 in consequence of the feed by means of the indexing roller 73 and the pivoting of the tension beam 70 and the breast beam 71 is thus the same as explained with regard to the first embodiment and'with reference to FIGURES 2 and 5. During this rotation of the control lever 87 its arm 110 rocks the lever 104 counterclockwise so that its roller 116 leaves the operable zone of the cam disk 114. When the carrier or support 74 has reached the mentioned normal operatingposition the pawl 78 under the action of the spring 79 falls into its recess 76. At the same time, the recess. 113 of the gear 92 comes into confronting relation with respect to the drive gear 112 so that its teeth come out of engagement and the gear 92 together with the cam disk 93 comes to standstill. More specifically, standstill of such member's occurs in the rotational position depicted in the drawing where the stop lever 98 again engages in the notch 96 and the pin of the control lever 87 engages in the radial section of the cam groove 91. In so doing, the rear flank of this radial section of the cam groove 91 serves, upon contact with the pin 90, as stop for arresting the cam disk 93 until this pin is again inwardly displaced by the control lever 87.

In the loom constructions depicted in FIGURESl and 6 it is not absolutely necessary to guide the warp threads between the warp beam 10 and the beat-up line 18 over a roller 15 and 70, respectively, the pivotal movement of which is forcefully coupled with that of the

rollers

26 and 71, respectively, which are pivoted for the different lengthwise displacement of the warp threads 11. The pivotal movement of the one of both

rollers

15, 26 and 70, 71 coupled with one another by the lever 38 and the support 74 respectively, only serve the purpose of maintaining approximately constant the tension of the warp threads between these rollers during pivoting of the other roller. In the described looms this occurs in that the support or contact position of each warp thread upon the rear deflecting roller 15 and upon the tension beam 70 is displaced due to its or their forcefully controlled pivoting through the same path in the same sense as the contact positions of the same warp threads at the forward deflecting roller 26 and upon the breast beam 71.

The same effect can be achieved by the arrangement which has been schematically illustrated in FIGURE 7. In this figure reference numeral 10 again designates the warp beam, 11 the warp threads delivered from such beam, 17 the harness group for the formation of the sheds 19 with the upper warp threads 11a and lower warp threads 11b, numeral 18 the location of the beat-up line, 27 the breast beam, 73 the indexing roller, 28 the pressure or contact roller, and 12 the cloth beam onto which the fabric 13 is wound. Reference character designates an apparatus for the variable lengthening of the path of the warp threads between the beat-up line 18 and the breast beam 27 which is parallel to the cloth beam 12. This apparatus can, for example, encompass as with the loom of FIGURE 1, a guide roller 25 and a deflecting roller 26 pivotally mounted at its one end. However, it could also encompass in accordance with a nonillustrated variant, an adjustable breast beam such as provided for the loom of FIGURE 6.

Instead of a second deflecting roller coupled with the other end of the deflecting roller 26 or an appropriately pivotal tension beam the loom of the embodiment of FIGURE 7 possesses an apparatus for automatic compensation of warp thread tension. This apparatus is arranged between the warp beam 10 and the harnesses 17 in place of the tension beam, and incorporates two guide rollers 121 and 1 22 which are mounted parallel to one another as well as to the warp beam 10. Additionally, such apparatus includes a dancer roller 123 which lies freely on the warp threads 11 between these

guide rollers

121 and 122 and is only guided with both of its end stubs 124 in vertical ,slots 125 of the frame side walls. The diameter of the dancer roller 123 substantially equals the inner spacing between the

guide rollers

121 and 122, so that it is always trained over half its circumference by the warp threads 11, and thus the tension force which it exerts upon these warp threads is only dependent upon its weight, not however, upon its elevational position. The dancer roller 123 thus holds the warp threads 11 and thereby the fabric 13 under constant tension.

If the path of all warp threads 11 of this fabric 13 are held at the same length between the guide roller 122 and the breast beam 12 by means of the apparatus 120, then these warp threads also build loops of equal length between the

guide rollers

121 and 122, and the axis of the dancer roller is disposed parallel to the axes of the

guide rollers

121, 122. On the other hand, if the path of the warp threads in the apparatus 120 is increased through a path which linearly increases from the one to the other side of the fabric 13, and thus the individual warp threads 15 are pulled forwardly through this path, then the loops formed by these warp threads between the

guide rollers

121 and 122 correspondingly shorten, and the dancer roller 123 is pulled upwardly an amount increasing from the mentioned one to the mentioned other side, without however, the tension force exerted by it upon these warp threads 11 and thus the tension of these threads changing. Insofar as the path through which the individual warp threads 11 in the apparatus 124) are pulled forwardly does not change linearly over the width of the fabric, then there appear small differences in the tension of the warp threads which are balanced or compensated by the elasticity of the threads.

It is to be understood that the apparatus 120 can be controlled with the same mechanism and in the same manner as the corresponding apparatus controlled by the lever 38 and the support 74 at the forward end of the looms of FIGURE 1 and FIGURES 6 respectively.

The loom illustrated in FIGURE 6 and previously described possesses the disadvantage that the weft threads 24 in the manufactured fabric are not located exactly at right angles to the warp threads 11. In order to prevent this, it would be possible to ensure that in a loom according to FIGURE 1 or FIGURE 6 during normal weaving operation the beat-up line 18 does not extend at a right angle to the warp threads 11, rather extends forwardly at an inclination from the left to the right, forming with the axis of the breast beam an angle of the magnitude or previously defined with respect to FIGURE 2. Since this angle differs in dependence upon the weft density it is necessary, then, that the position of the beat-up line is also changeable for normal operation in order to be able to produce fabrics at the loom having different weft density or compactness. However, since the to-and-fro movable members 22 which function as beat-up means 22b and form the movement reversal points of the beat-up line, also have to work as the shuttle drive means 22a, it is necessary that the path of the shuttles can be displaced together with the beat-up line.

Such a loom could be realised in the manner that the means or mechanism for inserting and beating the weft threads and incorporating the shuttles 21, the members 22 and their guide means, control means and drive means, are pivotal as a unit with respect to the loom frame about an axis which is vertical to the axes of the warp beam 10 and the cloth beam 12.

A variable displacement of the warp threads 11 for continuing weaving in the event of weft thread rupture would then also not be necessary, since for this purpose the mentioned mechanism would initially be pivoted as a unit such that the beat-up line extends at right angles to the warp threads as shown in FIGURE 3, whereafter it, in accordance with the insertion of new weft threads with simultaneous feed of the fabric and the warp by the indexing or controller roller is pivoted forwardly about the left terminal point of the beat-up line 18 in clockwise direction until it describes the angle or and has assumed its normal operating position. In order to effectuate such pivotal movement it would be possible to use similar apparatus as the apparatus depicted in FIGURES l and 6 for pivoting the deflecting rollers 15 and 26- or the tension beam '70 and the breast beam 71 respectively.

With such construction of the loom, the construction of the drive of the mechanism pivotal as a unit brings with it several difficulties. Above all, however, a certain mutual minimum spacing of the warp threads 11 would be necessary in order that the members 22 could carry out their to-and-fro movement perpendicular to the beat-up line 18' also then without obstruction if this beat-up line does not form a right angle with the warp threads. Under circumstances it is necessary to take into consideration that these members 22 during their return movement always somewhat press to the side the warp threads 11 and rub against such.

These disadvantages can be prevented if the beat-up means are not formed from the same elements as the shuttle drive means, as was the case with the beat-up means 22b of the previously described embodiments, rather such beat-up means are displacea-ble with respect to the shuttle drive means, and if means are provided which control the movement of these beat-up means in such a manner that their movement reversal points which form the fell or beat-up line 18 are disposed upon an at least approximately straight line which forms an adjustable angle with the direction of travel of the shuttles. Now, in FIGURES 8 to 10 there is shown a drive mechanism for a shuttle drive means and a beat-up means 131 associated with it. Additionally, there is depicted a mechanism for controlling the movement of a row of such beat-up means which fulfills these requirements.

The drive of each shuttle drive means 130 takes place, for example, from a non-illustrated cam which with the corresponding drive cams for the other shuttle drive means of the loom are seated upon a common control shaft which continuously rotates during loom operation. By means of this cam for each shuttle drive means 130 a rod 132 displaceable in a guide 133 provided at the loom frame is moved to-and-fro along a plane which is parallel to the warp threads 11 between a invariable forward terminal position 132a and an invariable rearward terminal position 13212. A shuttle drive means 130 is seated upon each rod 132 which in the rear terminal position 132b of the rod between both of the planes in which neighboring warp threads 11 are deflected by the harnesses 17 upwardly, threads 11a, and downwardly, threads 11b, extends past that thread 11b of these warp threads which has just been deflected downwardly and into the shed 19 which has just travelled past. In the forward terminal position 132a of the rod 132 the shuttle drive means 130 is located completely outside of the shed 19, as indicated with phantom lines at 130a of FIGURE 8.

In the upper region of each shuttle drive means 130 there is formed a dovetail-shaped recess 134 and a support surface 135 parallel to the direction of displacement of the shuttle drive means for the temporarily passing-by shuttles 21. The cycles of the to-and-fro movement of the individual rods 132 and the shuttle drive means 130 seated thereon are displaced in time towards one another in such a manner that the approximately vertical edges 134a bounding the recesses 134 at their rear form a sinus curve 136 (FIGURE 11), moving from the left to the right and continuing at right angles to the direction of movement of the rods 132. In FIGURE 11 reference character 136a designates the front extreme position and reference character 136b the rear extreme position of the mentioned edges 134a bounding the recesses 134, and with reference character a there is designated in FIG- URES 8 and 11, the stroke through which these edges move fore and aft, which stroke remains constant.

The rearwardly directed loops or bellies of this sinus curve 136 are disposed within the travelling sheds 19 formed from the warp threads by the harnesses 17. Each shuttle 21 at its lower face or underside possesses a rib 137 which fits into the recesses 134 of a number of shuttle drive means 130, the rear boundaries of which are just situated at the top or apex portion of one of the mentioned rearwardly directed bellies of the sinus curve, so that the relevant shuttle due to the to-and-fro movement of the shuttle drive means 130 is forced to travel transversely across the fabric width with this sinus curve belly in the appropriate shed 19 at right angles to the direction of movement of the rods 132 whereby it inserts between the

warp threads

11a and 11b the out-ofi weft thread 24 contained in such shuttle. In so doing, the shuttle 21 rests with a flat surface 138 disposed in front of the mentioned rib 137 upon the support surface 135 of the relevant shuttle drive means 130.

Behind the shuttle drive means 130, each rod 132 carries a pin 139 on which is pivotally mounted the corresponding beat-up means 131 constructed as a lever. Each beat-up means 131 extends above this pin 139 along the same plane as the associated shuttle drive means 130 between neighboring warp threads 11 to such an extent towards the top that it extends past each of these warp threads 11 also in that position where they are most pronouncedly deflected upwardly, i.e. threads 11a. Neighboring beat-up means 131 mutually brace themselves in lateral direction with the help of support shoes 149 provided at the upper end of the beat-up means 131. These support shoes 146 incorporate parallel lateral slide surfaces of sufficient length, in order that these shoes 140 also then contact one another when the neighboring beatup means 131 provided with such shoes form with one another the largest angle which occurs during operation.

Each beat-up means 131 is pivotally retained with its bifurcated or forked lower end 141 upon a pin 142 seated at a slide member 143. Of these slide members 143 each third one engages by means of

twopins

144, 145 in a slot or groove 146 of a stationary crossbeam 147 of the loom frame. This groove 146 extends parallel to the direction of movement of the drive rod 132. Since the slide means 143 laterally contact one another they are all guided in this manner parallel to the mentioned direction of movement. The lower faces of the slide means 143 bear against an adjustment or regulating lever 148 which is pivotally mounted upon a vertical pin 149 at the left side of the loom at the crossbeam 147 and at its upper face exhibits a lengthwise groovelStl. Each slide 143 carries a pin 144 which engages in this groove 150.

This last-mentioned pin for each third slide 143 is formed by the lower portion of the mentioned pin 144 and for the remaining slides is a special pin 151, as best ascertained by referring to FIGURE 10.

It will also be understood that for clarity in illustration, in FIGURES 9 and 10 there are shown considerably fewer slides 143 than the loom actually exhibits in practice and are required by the beat-up means 131 of FIG- URE 11, each of which require such a slide 143.

Now, during such time as the rods 132 move back and forth between the invariable extreme positions 1321: and 1321) they bring about that each beat-up means 131 with the associated pin 132 serving as the point of rotation oscillate back and forth about a practically constant angle between a forward extreme position 131a and a rear extreme position 1311). These extreme positions, however, are not invariable since the slides 143 which carry the individual pins 142 are variably displaceable by pivoting the lever 148 about the axis of the pin 149. In so doing, the individual slides 143 are displaced parallel to one another through paths which are proportional to the spacing of the axes of their guide grooves 146 from the axis of the pin 149 and thus linearly increase from the left to the right side of the loom. For instance, if the lever 148 is pivoted rearwa-rdly from one position in which its lengthwise groove 150 extends at right angles to the guide grooves 146 into the position according to FIGURE 9, then each slide 143 comes to rest somewhat further to the rear than that neighboring it towardsthe pin 149, that is, towards the left side of the loom. Accordingly, the pivot zones or regions 131a to 1311) of the individual beat-up means 131 displace to an increasing degree towards the front .from the left to the right side of the loom.

FIGURE 11 depicts the mode of operation of a wave weaving loom equipped with the apparatus according to FIGURES 8 to 10 with a position of the lever 148 which corresponds to normal operation of the loom. In this figure, the individual beat-up means 131 are schematically depicted in cross-section as taken along the plane XI-XI of FIGURE 8. At 131a there is depicted the line in which the forward edge of each beat-up means 131 comes to lie during its forward extreme position likewise designated in FIGURE 8, whereas reference character 131k represents the corresponding line for the rear extreme position for such beat-up means 131. Moreover, reference character [1 denotes the path through which pass the forward edges of the beat-up means 131 between both mentioned extreme positions, measured in the plane XLXL As can best be seen from FIGURE 11 the beat-up means 131 move in the same manner as the shuttle drive means according to a travelling sinus line or curve. However, in consequence of the inclined position of the lever 148 to a degree which decreases from the left to the right such as beating or beat-up means 131 are rear wardly displaced with respect to the shuttle drive means 130. The line 131a, which forms the geometric location of the forward extreme position of the forward edges of the beat-up means, is identical with the beat-up line 18. It forms a small angle with the direction perpendicular to the plane of the warp threads, that is, those weft threads 24 which have already been inserted and beaten in the fabric 13. The inclined position of the lever 148 is to be selected such that this small angle for the relevant weft thread density and the relevant spacing between the successively following shuttles 21 is equal to the previously defined angle a. It is also readily apparent from FIG- URE 11 that, in this case, the forward edges of the beatup means forming the top or peak of each forwardly directed wave belly of the beat-up sinus curve, in each case, measured in the direction of the warp threads, lies further forward by a weft thread division than the forward edges of the beat-up means forming the top or peak of the subsequent belly. Since between both of these wave bellies or loops a shuttle 21 inserts the right end of a new weft thread, each weft thread is beaten further rearwardly by a weft thread division than the weft thread introduced previous to such, so that all weft threads are beaten parallel to one another and perpendicular to the warp threads.

If rupture of a weft thread occurs then the loom is stopped and the lever 148 at the right side of the loom is pulled to the front until its lengthwise groove 150 is disposed at right angles to the direction of movement of the rods 132. As a result, the lines 131a (beat-up line) and 1311) which define the extreme positions of the beatup means 131, as viewed from the top (FIGURE 11) are turned in counterclockwise direction and come to lie at right angles to the warp threads 11 and parallel to the weft threads 24 of the fabric 13, as indicated at 131a and 1311]. Thereafter, there is removed the torn as well as those subsequently inserted weft threads and whose weft threads which are still in the shuttles within the fabric width, and the last weft thread 24 which has been completely inserted into the fabric is guided back up to the beat-up line 131a by pulling back the warp, where-' by the analagous condition of FIGURE 3 is then obtained.

Then, the loom including the feed of the fabric 13 and the warp can again be placed into operation, whereby care must be taken that the lever 148 during the time required for a shuttle 21 to pass through the entire fabric width is gradually again guided back into its normal operating position. The right end of the beat-up line which is now turned back from 131a to 131a thus follows the feed of the fabric 13, whereas its left end remains at its location, so that by virtue of the feed of the warp threads, space is provided in front of the beatup line for the further beat-up weft threads.

In order to actuate the lever 148- it is possible to provide an automatic control mechanism of basically the same construction as provided in FIGURE 1 for the pivoting of the lever 38 and in FIGURE 6 for the displacement of the support or carrier 74. Upon pivoting back the lever 148 the angle between the introduced weft thread 24 and the beat-up line increases in the same manner from 0 to a as such is seen in FIGURES 3, 4, 5 and FIGURE 2, with the exception that now the weft threads 24 remain l??? at right angles to the warp threads 11 and the beat-up line is disposed at an inclination.

-While there is 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 practiced within the scope of the following claims.

What is claimed is:

it. A method for resuming weaving of a fabric on a wave weaving loom after interruption of weaving due to a weft defect, the steps: while the loom is shut down bringing the weft thread last inserted before the weft defect into coincidence with a beat-up line; starting up the loom, and while the next weft thread is being inserted forming an angular spacing between said beat-up line and said weft thread last inserted such that each subsequently inserted weft thread is beaten up parallel to the previously inserted weft thread.

2. A method for resuming weaving of a fabric on a wave weaving loom after interruption of weaving due to a weft defect, the steps: while the loom is shut down removing the weft threads inserted subsequent to the weft defect up to and including the weft defect; bringing the weft thread last inserted before the weft defect into coincidence with a beat-up line over the entire width of the fabric; starting up the loom, and while the next weft thread is being inserted forming a spacing between said beat-up line and said weft thread last inserted which increases from the shuttle outlet side of the fabric to the shuttle inlet side of the fabric, such that each Subsequently inserted weft thread is beaten up parallel to the previously inserted weft thread.

3. A method for resuming weaving as claimed in claim 2, wherein the step of bringing into coincidence is effected by moving the beat-up line into coincidence with said last inserted weft thread, and the step of forming a spacin" is effected by moving the beat-up line back to its original position.

4. The method claimed in claim 3 comprising the step of pivoting as a unit an apparatus pivotally mounted at one side of the loom and containing a plurality of beating members and means for actuating the latter.

5. The method claimed in claim 3 comprising the step of variably moving the stroke range of each of a plurality of beating members.

6. The method claimed in claim 5 comprising the step of variable moving, in planes parallel to the warp threads, a plurality of pivots on each of which one of said heating members is pivoted.

7. The method for resuming weaving as claimed in claim 2, wherein the step of bringing into coincidence is effected by rearwardly moving the warp-threads near the beat-up line in the direction opposite to the movement of the fabric when the loom is running, the movement thereof increasing from the shuttle outlet side of the fabric towards the shuttle inlet side of the fabric; and wherein the step of forming a spacing is effected by forwardly moving the warp threads near the beat-up line in the direction of movement of the fabric when the loom is running, the movement thereof increasing from the shuttle outlet side of the fabric towards the shuttle inlet side of the fabric.

8. The method for resuming weaving as claimed in claim 7, wherein the rearward and forward movement of the warp threads is effected by changing the path length of the warp threads between the warp beam and the beat-up line and changing the path length of the warp between the beat-up line and the cloth beam a substantially equal and opposite amount, said changing of the path length increasing from the shuttle outlet side of the fabric towards the shuttle inlet side of the fabric.

9. A method for resuming weaving of a fabric as claimed in claim 8, wherein the step of changing the path length of the wrap threads between the warp beam and the beat-up line is carried out by pivoting a member extending transversely to the warp threads and in contact with the latter.

10. A method for resuming weaving of a fabric as craimed in claim 9, wherein the step of changing the path length of the warp threads between the beat-up line and the cloth beam is carried out by pivoting a member extending transversely to the warp threads and in contact with the fabric, both of the aforesaid members being pivotal at the same side of the loom.

11. A method for resuming weaving of a fabric as claimed in claim 8, wherein the step of changing the path length of the warp threads forming the fabric between the beat-up line and the cloth beam is carried out by pivoting a breast beam.

12. A method for resuming weaving of a fabric as claimed in claim 8, wherein the step of changing the path length of the warp threads between the warp beam and the beat-up line is carried out by pivoting a tension beam.

13. A method for resuming weaving of a fabric as claimed in claim 8, wherein the step of changing the path length of the warp threads between the beat-up line and the cloth beam is carried out by pivoting a member extending transversely to the warp threads and in contact with the fabric, and wherein the step of changing the path length of the warp threads between the warp beam and the beat-up line is carried out by means of an apparatus for maintaining constant warp thread tension in accord ance with changes in the warp thread tension.

14. A method for resuming weaving of a fabric as claimed in claim 8, including the steps of performing the weaving operation with said beat-up line being stationary and extending at right angles to the planes containing the warp threads, so that the weft threads directly after being beaten-up form an angle other than with the warp threads, and lengthening the path length of the portion of the fabric containing the warp threads between the beat-up line and the cloth beam through an increasing amount from the shuttle outlet side to the shuttle inlet side such that the weft threads of the fabric upon passing onto the cloth beam are disposed at right angles to the warp threads.

15. A member for resuming weaving of a fabric as claimed in claim 2 wherein the step of starting the loom initiates moving successive shuttles across the loom each for inserting a weft thread, and reciprocating each of a plurality of beating members up to said beat-up line and back therefrom for beating up the inserted weft threads, the step of forming said spacing between said beat-up line and said weft thread last inserted is effected during insertion of the next weft thread after starting the loom, by displacing the warp threads and the beat-up line relatively to each other by variable amounts increasing from the shuttle outlet side to the shuttle inlet side of the fabric, said method comprising the furher step of initiating uniform feeding of all warp threads after insertion of said next weft thread has been completed.

16. A method as claimed in claim 2 wherein the step of starting the loom initiates uniform feeding of all warp threads through the loom, moving successive shuttles across the loom each for inserting a weft thread, and reciprocating each of a plurality of beating members up to (said beat-up line and back therefrom for beating up the inserted weft threads, the step of forming said spacing between said beat-up line and said weft thread last inserted is effected during insertion of the next weft thread after starting the loom, by displacing the warp threads and the beat-up line relatively to each other, in the sense opposite to the displacement caused by the uniform feeding of the warp threads, by variable amounts increasing from the shuttle inlet side of the shuttle outlet side of the fabric.

17. An apparatus for resuming weaving of a fabric on a wave weaving 'loom after interruption of weaving due to a weft defect comprising, in combination. a warp beam for delivering warp threads, mechanism for simultaneously forming a plurality of sheds, means for inserting weft threads into said sheds, means for beating the inserted weft threads along a beat-up line, a cloth beam for receiving the woven fabric, and means bringing about a relative displacement between said beat-up line and the warp threads for bringing said beat-up line and the weft thread last inserted before the weft defect into coincidence.

18. An apparatus for resuming weaving of a fabric on a wave weaving loom after interruption of weaving due to a welt defect comprising, in combination, a warp beam for delivering warp threads, mechanism for simultaneously forming a plurality of sheds from said warp threads, means including shuttles for inserting weft threads into said sheds, means for beating the inserted weft threads along the beat-up line through which the warp threads pass, a cloth beam member for receiving a woven fabric, and means for bringing about a relative displacement for a desired period between said beat-up line and the warp threads passing through said beat-up line which displacement increases progressively from the outlet side of said shuttles to the inlet side thereof.

19. An apparatus as defined in claim 18 wherein said weft thread inserting means include shuttle drive elements, said shuttle drive elements and said beating means being constructed as individual components.

20. An apparatus as defined in claim 18 wherein said weft thread inserting means include shuttle drive elements, said shuttle drive elements and said beating means being constructed as common components.

21. An apparatus as defined in'claim 18 wherein said relative displacement means includes means for differently displacing in lengthwise direction the portions of the individual warp threads located in the region of the heating means.

22. An apparatus as defined in claim 21 wherein said relative displacement means comprises a device arranged at each side of said heating means for variably changing the length of the path of the individual warp threads and the portion of the fabric containing the warp threads at the relevant side of said heating means, means for operatiyely coupling said two devices with one another in such a manner that each change in length of the path of a warpthread brought about by one of said devices is opposite and at least approximately equal to the change in length of the path of the same warp thread at the opposite side of said beating means brought about by the other of said devices.

23. An apparatus as defined in claim 21 wherein said relative displacement means comprise a first device arranged at one side of said beating means for variably changing the length of the path of the individual warp threads and the portion of the fabric containing such war-p threads at said one side of said beating means, and a second device arranged at the opposite side of said beat ing means for at least approximately maintaining constant the tension of the individual warp threads.

24. An apparatus as defined in claim 23 wherein said second device for maintaining constant the tension of the individual warp threads incorporates a dancer roller.

25. An apparatus as defined in claim 21, further including a pair of parallel guide elements between which said warp threads move in a given path of travel, said relative displacement means for the portions of the individual warp threads located in the region of the beating means comprising at least one member arranged to one side of said heating means and extending transversely with respect to said warp threads, means for pivotally mounting said one member for variably deflecting the warp threads out of their path of movement between said guide elements.

26. An apparatus as defined in claim 18 wherein said beating means comprises individual to-and-fro moving heating elements, the forward-most reversal movement points of which form said beat-up line, and means for displacing said forwardmost reversal movement points of said beating elements in such a manner that there is brought about an angular displacement of said beat-up line about a point located at the region of one edge of the weaving zone.

27. An apparatus as defined in claim 26 wherein said heating means is constructed as a unit which is pivotally mounted at one side of the loom.

28. An apparatus as defined in claim 26 further including parallel track means upon which said individual beating elements can move to-and-fro, said dispacing means for said beating elements differently displacing the range of stroke of said beating elements along said track means.

29. An apparatus as defined in claim 28 wherein said weft thread inserting means includes shuttle drive elements, each of said individual heating elements being movably connected with a shuttle drive element displaceable toand-fro in a constant range of stroke, each beating element being driven by its shuttle drive element.

30. An apparatus as defined in claim 29, said displacing means for said beatin-g elements further including a respective pin member upon which each heating element is mount-ed to rock back and forth, said pin member being guided parallel to the plane of pivoting of its associated beating element, and lever means mounted at one side f the weaving zone common to all heating elements for displacing said pin members.

31. An apparatus as defined in claim 18 wherein said means for bringing about said relative displacement between said beat-up line and said warp threads passing through said beat-up line comprise control means synchronously driven with said weft thread inserting means and said heating means for automatically annihilating the relative displacement between said beat-up line and the warp threads passing through said beat-up line.

32. An apparatus as defined in claim 31 further including an indexing mechanism for effecting uniform feed of all of the warp threads, said control means incorporating an adjusting mechanism for maintaining the speed with which said relative displacement is annihilated by said control means proportional to the speed of the uniform feed of all of the warp threads effected by said indexing mechanism.

33. An apparatus as defined in claim 32 wherein said control means incorporates a further adjusting mechanism for regulating the relationship of the speed with which said relative displacement is annihilated to the speed of operation of said weft thread inserting means and said beating means, said further adjusting mechanism being adapted to be operatively coupled with an adjusting mechanism which controls the relationship of the speed of uni form feed of all of the warp threads effected by an indexing mechanism to the speed of operation of the weft thread inserting means and the beating means.

References Cited UNITED STATES PATENTS 1,316,159 9/1919 Jackson 139-188 2,587,009 2/1952 Sutherland 139-188 2,845,093 7/1958 Dietzsch et al 139-12 2,884,015 4/1959 Bechter 139-291 3,165,125 1/1965 Tinkham 139-291 3,173,455 3/1965 McClure 139-291 MERVIN STEIN, Primary Examiner.

H. S. JAUDON, Assistant Examiner.

Claims

1. A METHOD FOR RESUMING WEAVING OF A FABRIC ON A WAVE WEAVING LOOM AFTER INTERRUPTION OF WEAVING DUE TO A WEFT DEFECT, THE STEPS: WHILE THE LOOM IS SHUT DOWN BRINGING THE WEFT THREAD LAST INSERTED BEFORE THE WEFT DEFECT INTO COINCIDENCE WITH A BEAT-UP LINE; STARTING UP THE LOOM, AND WHILE THE NEXT WEFT THREAD IS BEING INSERTED FORMING AN ANGULAR SPACING BETWEEN SAID BEAT-UP LINE AND SAID WEFT THREAD LAST INSERTED SUCH THAT EACH SUBSEQUENTLY INSERTED WEFT THREAD IS BEATEN UP PARALLEL TO THE PREVIOUSLY INSERTED WEFT THREAD.