GB1603964A

GB1603964A - Looms

Info

Publication number: GB1603964A
Application number: GB19289/78A
Authority: GB
Original assignee: Sulzer AG; Gebrueder Sulzer AG
Current assignee: Sulzer AG
Priority date: 1977-05-12
Filing date: 1978-05-12
Publication date: 1981-12-02
Also published as: CH619993A5; JPS5418956A; AT356028B; IT7823244A0; DE2724923A1; FR2390526A1; DE2724923C3; IT1095125B; FR2390526B3; DE2724923B2; ATA382077A

Abstract

In the weaving machine, weft threads (31) are each inserted by means of an airjet from a weft unit (25, 26) simultaneously from outside towards the centre into two weaving tracks (12, 12a) arranged next to one another. The insertion capacity can thereby be increased in comparison with an alternating weft insertion from the middle of the two tracks. If the weaving width is relatively large, there are no misgivings that the two simultaneous air-insertion jets directed from outside towards the centre could interfere with one another in the central aisle (32) between the two weaving tracks (12, 12a) and impede the formation of a respective selvedge (36) along the middle aisle (32). <IMAGE>

Description

(54) LOOMS (71) We, SULZER BROTHERS LIMITED, a Company organised under the laws of Switzerland, of Winterthur, Switzerland, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to a loom constructed to operate with at least one pair of laterally adjacent sheets of warp threads, and employing jet insertion of the weft threads, for instance air jet insertion. The term "laterally adjacent" when used herein, will be understood to refer to adjacent sets of warp threads spaced from one another in a direction parallel to the planes of the sheets.The terms "inner" and "outer" edges of a sheet of warp threads or of a fabric will be understood to relate to the edges respectively closest to and farthest from the other sheet of the pair during weaving.

In a loom of this construction described in Offenlegungsschrift 2 049 373 of the German Federal Republic, there is between the two sheds a rotatable combined weft insertion mechanism having two air nozzles which can be rotated through 1800 in accord ance with a control program. In this way it is possible to accomplish selection of the weft threads. Thus, for instance, prior to each pick the air nozzle arrangement is rotated, so that there can be inserted into each shed alternately first one type of weft thread and then the other.

The supply of the weft threads to the weft insertion mechanism and equally the arrangement of the associated weft thread supply bobbins is relatively complicated with this insertion system where the insertion of the weft threads is undertaken from a position between the two sheds.

According to the present invention, there is provided a loom which is constructed to operate with at least one pair of laterally adjacent sheets of warp threads and which has means for forming a shed from each sheet of warp threads and a jet weft insertion mechahism for each shed, the insertion mechanism being arranged to insert weft threads simultaneously into the two sheds from the outer edge of the respective shed towards the inner edge thereof, and means for beating-up the inserted weft thread for each shed, the said shed forming means and/or the said beating-up means being operatively associated with both sheets of warp threads.

With this construction, the arrangement of the weft thread supply bobbins or the like, especially when using several different weft threads, for instance threads of different colours, is simpler, because the bobbins or spools or other thread packages can be arranged closer to the related weft insertion mechanism. Adequate space is available adjacent the outer edges of both sheets of the pair. Also, the weft threads can be inserted without any appreciable change of direction at the point of pick. Any required temporary weft thread storage devices, for instance drum storages, can also be accommodated without difficultly between the weft thread bobbins and the weft insertion mechanisms.

It might be thought that difficulties might arise from simultaneously inserting by jet two weft threads into two adjacently situated sheds from the outside thereof. It might be thought that the insertion jets-which are directed towards one anothercould interfere with one another in the centre portion between the two sheds. At that location there could be rendered more difficult the formation of a uniform selvage. However, in the case of larger sheet widths it has been found that these possible fears are unjustified. In any case, certain preferred constructions to be described minimise the risks of mutual disturbance to the two jets and render possible the formation of acceptable selvages at the inner edges of the fabrics woven on the loom.

For instance, in one construction the loom includes auxiliary nozzles arranged along the weft insertion path of each shed for generating auxiliary jets effective during the insertion of the weft threads, the construction being such that the outflow velocity of the auxiliary jets of auxiliary nozzles which are situated closer to the inner edges of the sheds is smaller than the outflow velocity of auxiliary nozzles situated more remotely from the inner edges.Alternatively, the loom may include auxiliary nozzles arranged along the weft insertion path of each shed for generating auxiliary jets effective during the insertion of the weft threads, the angles enclosed between the weft insertion path and the directions of the jets of auxiliary nozzles which are situated closer to the inner edges of the sheds being greater than the corresponding angles of auxiliary nozzles situated more remotely from the inner edges. Clearly the auxiliary nozzles may be arranged to have both differential velocities and different angles.Thus there can be achieved the beneficial result that the weft insertion jets are weakened in the direction of the central region between the two sheds to such an extent that they no longer mutually obstruct or disturb one another in the region of the central region, even if no barrier is provided between the two sheds central region.

In one possible construction, the loom includes a barrier between the two sheds to separate the two insertion jets. The barrier can merely have a separation effect for the insertion jets on opposite sides thereof, for instance it can be designed as an impact wall, or, if desired, can have means defining deflection surfaces for the weft insertion jets on both sides of the barrier. However, the barrier can also constitute a common catching motion for both picks of the weft insertion mechanism. The barrier may constitute a common suction device for the insertion jets and, if desired, the ends of the inserted weft threads. Also, the barrier can serve for sucking-up the severed ends of the weft threads which have been cut off at the centre lane.

The invention may be carried into practice in various ways but one loom embodying the invention and several modifications of the loom will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 is a perspective, schematic view of an air jet insertion twin loom embodying the invention, viewed essentially from the cloth end; Figure 2 is a schematic rear view of the loom shown in Figure 1 looking from the warp thread end; and Figures 3, 4 and 5 respectively show on an enlarged scale different modifications of the loom of Figures 1 and 2.

Figures 1 and 2 show a twin loom 1, this term meaning a loom capable of weaving two fabrics simultaneously. The loom comprises two side frames 2, a two-part warp beam 3, 3a from which are unwound the warp threads which are delivered over a back rest 5, 5a. The warp threads pass through the healds 7 of shafts 6 in the form of two sheets 12 and 12a while forming the shed 40. Thereafter, the warp threads 4 pass through two reeds 8 and 9 to the fell 11. The thus formed fabrics 30 and 30a are drawn by a cloth take-up roll 13 and wound on to a cloth beam 15 after passing around a guide roll 14. The roll 13 and the beam 15 are driven by means of a schematically indicated cloth take-up motion 41.

As best seen by referring to Figure 2, the warp beam 3, 3a is mounted in an intermediate bearing 16 carried by a floormounted pedestal 17. As schematically indicated by the phantom line 52, the pedestal 17 can be upwardly extended and have a bearing 53 for the shaft 54 of the back rest, which will then be a two-part back rest 5, Sa supported at its intermediate region by a bearing 53 on the pedestal extension 52. The pedestal 17 can also be used to support other rolls and beams of the loom, such as guide rolls.

The warp beam 3, 3a is rotated by a conventional warp let-off motion 18 as indicated schematically in Figure 1. The shafts 6 extend across the entire width of both sheets 12 and 12a which collectively form the pair 27. There are separate reeds 8 and 9 for the two sheets 12 and 12a but they are secured to a common sley shaft 20 and thus jointly driven. Hence, they operate in-phase.

Weft threads from two spools 21, 22 are simultaneously inserted into the two sheds 40 of the warp threads4 by means of respective weft insertion mechanisms 25 and 26 arranged externally of the pair 27. Here insertion of the weft is accomplished by air jets 50 which are discharged from respective compressed air nozzles 29 mounted on the associated weft insertion mechanisms 25 and 26.

The weft insertion path which has been indicated by a dotted line 31 extends through guide teeth 32a. Between the two sheets 12 and 12a there is a free, central region 32 where there is a combined double catching motion 33 for both of the inserted weft threads 23 and 24. This double catching motion 33 has on each side a respective suction nozzle 34 for the inserted weft thread and for cut thread remains. Tucked selvages 38 are formed at the inner edges 36 and 37 of the webs 12 and 12a by means of tucking needles (not shown) forming parts of the catching motion. The tucked selvages 38 contain the tucked ends of the weft threads. Similar tucked selvages 38 can be formed at the outer edges of both cloth webs 30 and 30a.

The cloth take-up roll 13 and the cloth beam 15 are continuous across both fabrics 30, 30a and are rotated by the control device 41 shown schematically in dotted lines. Both of the weft insertion mechanisms 25, 26 can be moved in and out along the weft insertion path 31 and fixed in position by means, not shown; for example, Figure 2 shows one of the insertion mechanisms moved to and fixed in the position 26a.

Instead of using a central combined catching motion 33, as shown in Figure 1, it would be possible to provide two separate catching motions adjacent one another in the central region 32. Each of these two catching motions can be mounted to be movable and positionally fixed along the weft insertion path 31.

While with the construction shown in Figure 1, the catching motion 33 forms a barrier unit between the air insertion jets which are directed towards suction funnels 34 on opposite sides of the catching motion, the combined catching motion which is shown in Figure 3 and which may be substituted for that shown in Figure 1 has twocurved surfaces 44. The air insertion jets are directed towards these two curved surfaces from opposite sides of the barrier unit 43 and they are thus deflected upwardly in the direction of the arrows 45.

Figure 4 shows a modified sley which may be substituted for that shown in Figure 1.

In the modified sley auxiliary nozzles 46, 47 and 48 are mounted at the bases of certain of the guide teeth 32a. By means of the auxiliary jets K, L, M which emanate from these auxiliary nozzles 46, 47 and 48, respectively, the weft thread 24 during its passage through the shed 40 of the related sheet 12 is further transported and supported from below. These auxiliary nozzles 46, 47 and 48 can be connected to operate all at the same time or else in sequence so that each begins to operate a short time after the preceding one so that there is formed a travelling jet.With the construction under consideration all of the jets delivered by the auxiliary nozzles 46, 47 and 48 make the same angle A with the weft insertion path 31 but it is arranged that the auxiliary jet K from the auxiliary nozzle 46 travels at a greater speed or pressure than the auxiliary jet L flowing from the auxiliary nozzle 47 which is situated closer to the central lane 32. This has been schematically indicated by the shorter arrow of the jet L effluxing from the auxiliary nozzle 47. The jet M from the auxiliary nozzle 48 has a lower velocity still. These auxiliary jets K, L and M are particularly advantageous when weaving large width fabrics.

Another sley which may replace that shown in Figure 1 is shown in Figure 5. This has auxiliary jets similar to those shown in Figure 4 but the angle B between the auxiliary jet L effluxing from the auxiliary nozzle 47 and the weft insertion path 31 is greater than the angle A formed by the auxiliary jet K emanating from the auxiliary nozzle 46. The angle C at the auxiliary nozzle 48 is again greater than the angle B. The auxiliary nozzles 46, 47 and 48 are so directed that their effiuxing jets form an increasingly larger angle with the weft insertion path 31 the closer that each of such nozzles is situated to the central region 32. On the other hand, the velocity of the auxiliary jets decreases as the central region 32 is approached, this being indicated in Figure 5 by the decreasing lengths of the arrows associated with the jets K, L and M.With steeper or more inclined auxiliary jets it is adequate to have a correspondingly lower jet velocity.

The deflecting surfaces 44 and the arrangements of the auxiliary nozzles 46, 47 and 48 shown in Figures 4 and 5 achieve the result that the simultaneous, opposingly directed jets do not mutually hinder one another in the sheets 12 and 12a adjacent the central region 32.

With the construction illustrated in Figures 1 and 2 the components for shed forming, namely the shafts, and the components for beating-up, namely the reeds 8 and 9, are common to both sheets 12 and 12a. Both groups of components operate in-phase over the entire web width of the twin loom 1. Also both of the partial warp beams 3, 3a, i.e.

the parts forming the two-part warp beam 3, 3a, as well as the rolls 13 and 14 at the cloth take-off end of the loom operate in-phase for both sheets 12 and 12a since their shafts are continuous across the width of the loom.

It is, of course, possible to provide between the weft supply bobbins 21 and 22 and the weft insertion mechanisms 25 and 26 temporary weft storage devices, for instance drum stores, from which the required weft for each pick can easily be pulled-off under constant tension.

Also, the intermediate, combined catching motion 33 can, if desired, be movable along the weft insertion path 31 with means for fixing it in the selected position as for the weft insertion mechanisms 25 and 26, for example by being mounted on a rod extending across the width of the loom.

There can, of course, be a greater number of sheet pairs pairs 27 arranged adjacent one another, with each sheet containing two sheets 12 and 12a and the corresponding devices for weft insertion, shed forming, beating up and so forth. Also, it is possible to insert the weft by water jets instead of by air jets.

Attention is drawn to our copending British Patent Application No. 19290/78 (Serial No. 1603965) and No. 19291/78 (Serial No. 1603966).

WHAT WE CLAIM IS: 1. A loom which is constructed to operate with at least one pair of laterally adjacent sheets of warp threads and which has means for forming a shed from each sheet of warp threads and a jet weft insertion mechanism

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. shown; for example, Figure 2 shows one of the insertion mechanisms moved to and fixed in the position 26a. Instead of using a central combined catching motion 33, as shown in Figure 1, it would be possible to provide two separate catching motions adjacent one another in the central region 32. Each of these two catching motions can be mounted to be movable and positionally fixed along the weft insertion path 31. While with the construction shown in Figure 1, the catching motion 33 forms a barrier unit between the air insertion jets which are directed towards suction funnels 34 on opposite sides of the catching motion, the combined catching motion which is shown in Figure 3 and which may be substituted for that shown in Figure 1 has twocurved surfaces 44. The air insertion jets are directed towards these two curved surfaces from opposite sides of the barrier unit 43 and they are thus deflected upwardly in the direction of the arrows 45. Figure 4 shows a modified sley which may be substituted for that shown in Figure 1. In the modified sley auxiliary nozzles 46, 47 and 48 are mounted at the bases of certain of the guide teeth 32a. By means of the auxiliary jets K, L, M which emanate from these auxiliary nozzles 46, 47 and 48, respectively, the weft thread 24 during its passage through the shed 40 of the related sheet 12 is further transported and supported from below. These auxiliary nozzles 46, 47 and 48 can be connected to operate all at the same time or else in sequence so that each begins to operate a short time after the preceding one so that there is formed a travelling jet.With the construction under consideration all of the jets delivered by the auxiliary nozzles 46, 47 and 48 make the same angle A with the weft insertion path 31 but it is arranged that the auxiliary jet K from the auxiliary nozzle 46 travels at a greater speed or pressure than the auxiliary jet L flowing from the auxiliary nozzle 47 which is situated closer to the central lane 32. This has been schematically indicated by the shorter arrow of the jet L effluxing from the auxiliary nozzle 47. The jet M from the auxiliary nozzle 48 has a lower velocity still. These auxiliary jets K, L and M are particularly advantageous when weaving large width fabrics. Another sley which may replace that shown in Figure 1 is shown in Figure 5. This has auxiliary jets similar to those shown in Figure 4 but the angle B between the auxiliary jet L effluxing from the auxiliary nozzle 47 and the weft insertion path 31 is greater than the angle A formed by the auxiliary jet K emanating from the auxiliary nozzle 46. The angle C at the auxiliary nozzle 48 is again greater than the angle B. The auxiliary nozzles 46, 47 and 48 are so directed that their effiuxing jets form an increasingly larger angle with the weft insertion path 31 the closer that each of such nozzles is situated to the central region 32. On the other hand, the velocity of the auxiliary jets decreases as the central region 32 is approached, this being indicated in Figure 5 by the decreasing lengths of the arrows associated with the jets K, L and M.With steeper or more inclined auxiliary jets it is adequate to have a correspondingly lower jet velocity. The deflecting surfaces 44 and the arrangements of the auxiliary nozzles 46, 47 and 48 shown in Figures 4 and 5 achieve the result that the simultaneous, opposingly directed jets do not mutually hinder one another in the sheets 12 and 12a adjacent the central region 32. With the construction illustrated in Figures 1 and 2 the components for shed forming, namely the shafts, and the components for beating-up, namely the reeds 8 and 9, are common to both sheets 12 and 12a. Both groups of components operate in-phase over the entire web width of the twin loom 1. Also both of the partial warp beams 3, 3a, i.e. the parts forming the two-part warp beam 3, 3a, as well as the rolls 13 and 14 at the cloth take-off end of the loom operate in-phase for both sheets 12 and 12a since their shafts are continuous across the width of the loom. It is, of course, possible to provide between the weft supply bobbins 21 and 22 and the weft insertion mechanisms 25 and 26 temporary weft storage devices, for instance drum stores, from which the required weft for each pick can easily be pulled-off under constant tension. Also, the intermediate, combined catching motion 33 can, if desired, be movable along the weft insertion path 31 with means for fixing it in the selected position as for the weft insertion mechanisms 25 and 26, for example by being mounted on a rod extending across the width of the loom. There can, of course, be a greater number of sheet pairs pairs 27 arranged adjacent one another, with each sheet containing two sheets 12 and 12a and the corresponding devices for weft insertion, shed forming, beating up and so forth. Also, it is possible to insert the weft by water jets instead of by air jets. Attention is drawn to our copending British Patent Application No. 19290/78 (Serial No. 1603965) and No. 19291/78 (Serial No. 1603966). WHAT WE CLAIM IS:

1. A loom which is constructed to operate with at least one pair of laterally adjacent sheets of warp threads and which has means for forming a shed from each sheet of warp threads and a jet weft insertion mechanism

for each shed, the insertion mechanism being arranged to insert weft threads simultaneously into the two sheds from the outer edge of the respective shed towards the inner edge thereof, and means for beating-up the inserted weft thread for each shed, the said shed forming means and/or the said beating-up means being operatively associated with both sheets of warp threads.

2. A loom as claimed in Claim I in which each weft insertion mechanism is an air jet weft insertion mechanism.

3. A loom as claimed in Claim 1 or Claim 2 which includes auxiliary nozzles arranged along the weft insertion path of each shed for generating auxiliary jets effective during the insertion of the weft threads, the construction being such that the velocity of the auxiliary jets of auxiliary nozzles which are situated closer to the inner edges of the sheds is smaller than the velocity of auxiliary nozzles situated more remotely from the inner edges.

4. A loom as claimed in Claim 3 in which the angles enclosed between the weft insertion path and the directions of the jets of auxiliary nozzles which are situated closer to the inner edges of the sheds are greater than the corresponding angles of auxiliary nozzles situated more remotely from the inner edges.

5. A loom as claimed in Claim 1 or Claim 2 which includes auxiliary nozzles arranged along the weft insertion path of each shed for generating auxiliary jets effective during the insertion of the weft threads, the angles enclosed between the weft insertion path and the directions of the jets of auxiliary nozzles which are situated closer to the inner edges of the sheds being greater than the corres ponding angles of auxiliary nozzles situated more remotely from the inner edges.

6. A loom as claimed in any of the pre ceding claims which includes a barrier between the sheds of the pair to separate the two insertion jets.

7. A loom as claimed in Claim 6 in which the barrier is constituted by a common catching motion for both picks of the weft insertion mechanisms.

8. A loom as claimed in Claim 6 in which the barrier is constituted by a common suction device for the jets of both weft insertion mechanisms.

9. A loom as claimed in Claim 6 in which the barrier includes means defining deflection surfaces for the weft insertion jets on both sides of the barrier.

10. A loom as claimed in any of Claims 6 to 9 in which the barrier is mounted on the loom to be movable along the path of weft insertion and there is means to lock the barrier in a selected position.

11. A loom as claimed in any of the preceding claims in which at least one of the weft insertion mechanisms is mounted on the loom to be movable along the path of weft insertion and there is means to lock the weft insertion mechanism in a selected position.

12. A loom as claimed in any of the preceding claims which includes two spaced side frames between which there extend a plurality of shafts and a floor-mounted pedestal located between the two side frames and supporting at least one of the shafts.

13. A loom as claimed in Claim 12 when appendant to Claim 6 in which the pedestal is located beneath the barrier.

14. A loom as claimed in Claim 12 or Claim 13 which includes a cloth guide roll supported by the pedestal.

15. A loom as claimed in Claim 12 or Claim 13 or Claim 14 which includes a warp beam supported by the pedestal.

16. A loom constructed and arranged to operate substantially as described herein with reference to Figures 1 and 2 of the accompanying drawings.

17. A loom as claimed in Claim 16 and modified substantially as described herein with reference to Figure 3 or Figure 4 or Figure 5 of the accompanying drawings.