WEFT THREADS SAVING DEVICE FOR WEAVING MACHINES

Abstract

A weft threads saving device for shuttle-less weaving machines comprises a comb (2), a temple (3), a guiding plane (6), a fixed blade (4), a movable blade (5) of a shear (17), a fabric winding cylinder (8) and a suction system (7) connected both to the guiding plane (6) and to the fixed blade (4) of the shear (17).

Claims

1-12. (canceled)

13. A weft threads saving device for shuttle-less weaving machines suitable for making a fabric, said device being located and operating between a fabric-forming area which comprises a comb configured to beat the weft tails of the fabric and a temple configured to transversely stretch said fabric, said comb and said temple being positioned on an opposite side with respect to a cylinder configured to wrap the fabric, said weft threads saving device comprising a guiding plane for guiding said fabric, which is located downstream of said comb and of said temple, and a shear having a fixed blade, which is located below said fabric and downstream of said guiding plane, and a movable blade cooperating with said fixed blade, wherein said weft threads saving device also comprises: pneumatic and/or mechanical devices, configured for sliding said weft tails of the fabric onto said guiding plane and towards said fixed blade and said movable blade of said shear, thus maintaining said weft tails of the fabric protruding and extended; a suction system, positioned below said guiding plane and below said fixed blade of said shear, which is configured to recover excess weft tails of the fabric.

14. A weft threads saving device according to claim 13, wherein said saving device comprises at least two opposed strips placed in contact with the sides of said fabric, said strips having a front part placed next to said temple.

15. A weft threads saving device according to claim 14, wherein the distance between said at least two strips is progressively increasing along the cutting direction of said fixed and movable blades of said shear.

16. A weft threads saving device according to claim 13, wherein said at least two strips, between which the sides of the fabric run, are configured to push a plurality of said weft tails of the fabric between said strips and a guiding edge facing said strips.

17. A weft threads saving device according to claim 13, wherein in a spaced portion of said at least two strips, said weft tails are sucked by said suction system and brought close to said guiding plane, so that said weft tails are able to reach said fixed and movable blades of said shear.

18. A weft threads saving device according to claim 13, wherein said saving device comprises a first disk, which is carved in a radial pattern and sloped with respect to a vertical axis of rotation, said first disk leaning against at least a portion of said fabric.

19. A weft threads saving device according to claim 18, wherein said first disk is elastically connected with and placed opposite to a second disk.

20. A weft threads saving device according to claim 19, wherein said first and second disks rotate arranging said weft tails as a plurality of fringes, said weft tails running along said guiding plane and on said fixed blade of said shear, so that said fixed and movable blades of the shear are able to cut said excess weft tails of the fabric.

21. A weft threads saving device according to claim 18, wherein said first and second disks rotate arranging said weft tails as a plurality of fringes, said weft tails running along said guiding plane and on said fixed blade of said shear, so that said fixed and movable blades of the shear are able to cut said excess weft tails of the fabric.

22. A weft threads saving device according to claim 13, wherein said suction system comprises a suction nozzle made with a series of wrapped and superimposed layers with a spiral-shaped section, of which at least two layers are configured so that said fabric longitudinally slides and at least one third layer is configured to suck and prepare for cutting said weft tails, by means of at least one of said fixed and movable blades of the shear.

23. A weft threads saving device according to claim 22, wherein said suction nozzle is configured to maintain said weft tails in a mutually parallel position and in a position perpendicular to the edge of said fabric until said fabric (1) exits from said temple.

24. A weft threads saving device according to claim 23, wherein said suction nozzle uses said guiding plane as a support plane for an elastic gripping element, which is configured to grip the weft tails of said fabric, said weft tails sliding towards said fixed and movable blades of said shear.

25. A weft threads saving device according to claim 22, wherein said suction nozzle uses said guiding plane as a support plane for an elastic gripping element, which is configured to grip the weft tails of said fabric, said weft tails sliding towards said fixed and movable blades of said shear.

26. A weft threads saving device according to claim 25, wherein said suction nozzle, which is located downstream of said temple, is configured to suck said weft tails of the fabric which are previously cut by said fixed and movable blades of said shear, so that said weft tails are retrieved at an exit side of the fabric, by means of said elastic gripping element.

27. A weft threads saving device according to claim 24, wherein said suction nozzle, which is located downstream of said temple, is configured to suck said weft tails of the fabric which are previously cut by said fixed and movable blades of said shear, so that said weft tails are retrieved at an exit side of the fabric, by means of said elastic gripping element.

Description

[0027] These and other objects are achieved by a weft saving device for weaving machine according to the invention, described in greater detail hereinafter in the present description of a preferred, but not exclusive embodiment thereof, provided by way of non-limiting example in the accompanying drawings, in which:

[0028] FIG. 1 diagrammatically shows a partial and partially sectional view of a portion of the loom in which the device according to the present invention is illustrated;

[0029] FIG. 2 diagrammatically shows a front view of two thread interlacing types; in particular, FIG. 2a diagrammatically shows an interlacing with four crossed threads, while FIG. 2b diagrammatically shows a two-thread helical interlacing;

[0030] FIG. 3 diagrammatically shows a view from the top of a first embodiment of the device for weaving machine according to the present invention;

[0031] FIG. 4 relates to a top view of a second embodiment of the device for weaving machine according to the present invention;

[0032] FIG. 4a is an inclination angle view of an element, according to the second embodiment of the device for weaving machine according to the present invention;

[0033] FIG. 5 relates to a top view of a third embodiment of the device for weaving machine according to the present invention;

[0034] FIG. 5a is a section view taken along line A-A in FIG. 5;

[0035] FIG. 6 relates to a top view of a fourth embodiment of the device for weaving machine according to the present invention.

[0036] With reference to the aforesaid figures, the weft saving device for weaving machines of the present invention, as shown in FIG. 1, is a structure placed between a comb 2 and a temple 3 for the formation of the fabric, placed on one side, and a fabric winding cylinder 8, placed on the other side, downstream from the comb 2 and temple 3.

[0037] In the portion between the temple 3 and the cylinder 8, the edge of the fabric slides on a fixed guiding plane 6 placed at the exit of the temple 3 in the direction of the cylinder 8 and on a subsequent guiding section consisting of the lower blade 4, in a fixed position parallel to the fabric, of a shear 17. The second movable blade 5, e.g. of the oscillating type, of the shear 17 cuts the weft protrusions to the desired length.

[0038] Several devices, alternatively of pneumatic and/or mechanical type, which are suitable for controlling the correct tension of the weft tails and the preparation to cut are positioned at the exit of the temple 3 and before the blades 4 and 5 of shear 17. The weft tails are prepared to cut the excess parts by a suction system 7 and then cut to a predetermined length from the edge of the fabric 1.

[0039] The suction system is in position under the blades 4 and 5 and is connected to the fixed guiding table 6 and the fixed blade 4 of the shear 17.

[0040] The edge of fabric 1 is stabilized with specific warp and weft interlacing after each beat of the comb 2. FIG. 2a shows the interlacing 9 with four crossed threads which the side binding of the inserted wefts ensures the necessary tension for the regularity of the weft/weft interlacing between the center and the sides of the fabric; such interlacing 9 may be provided with the use of the device according to the invention and allows to eliminate the draw of the split selvages. Alternatively, if allowed by the fabric, a similar function may be provided by a two-thread helical interlacing 10, as shown in FIG. 2b.

[0041] The cutting method of the weft tails is illustrated in figures from 3 to 6 in alternative versions, e.g. such as mechanical, pneumatic, and/or mixed versions.

[0042] FIG. 3 shows a first embodiment of the present invention with a solution for controlling the weft tails comprising two opposing strips 11, 12, e.g. metallic and elastic, which are placed in contact on both sides of the fabric 1 and with the front part P near the temple 3.

[0043] The distance between the strips 11, 12 increases progressively along the cutting direction of the shear 17 and the profile of the aforesaid strips 11, 12, between which the edge of fabric 1 slides, pushes the weft tails outwards, which are first grouped towards a guiding edge MG, while the fabric 1 slides towards the cylinder 8.

[0044] In the spaced portion of the strips 11, 12 the weft tails are sucked by the suction system 7 and brought close to the guiding plane 6 under and the fixed blade 4 until they are cut by the movable blade 5 of the shear 17.

[0045] FIG. 4 shows a further embodiment of the invention, in which the device comprises a very thin and flexible metal disk 13, which is carved in a radial pattern, placed in contact with fabric 1 on an arc of its contour; the disk 13 is set in rotation by the feeding of the fabric 1 and by the radial shape and inclination a of its rotation axis (FIG. 4a).

[0046] The metal disk 13 is elastically opposed to a second disk 13′, under the fabric 1 with a specular arrangement to that of the disk above.

[0047] The two disks 13, 13′, by rotating pushed by the feeding of the fabric 1, arrange the weft tails which slide on the guiding table 6 and on the fixed blade 4 of the shear 17 as a fringe towards the outside of the fabric edge, in a position under the fabric 1, to be prepared for the cutting of the shear 17.

[0048] FIG. 5 shows a further embodiment of the device according to the present invention, comprising a suction nozzle 15 with flaps wound and overlapped as indicated in section A-A in FIG. 5a, with the edge of the fabric 1 which slides longitudinally in contact between the upper flap 14a and the lower flap 14b, while the compartment underneath has the function of sucking the weft tails for cutting with the shear 17 and preparing them on the guiding plane 6 and the fixed blade 4.

[0049] FIG. 6 shows another embodiment of the device according to the invention, wherein a suction nozzle 15 is used suitably arranged to keep the weft tails parallel to each other and in a position perpendicular to the edge of the fabric 1 until the exit from temple 3; the functional criteria are the same as described in the previous cases.

[0050] In this case, at the exit side of the weft from the warp mouth, the tails released by an exit rapier are recovered, with a part of the suction nozzle 15, which, placed beyond the temple 3 and with a suitable shape, forms the continuous guiding plane 6 with the fixed blade 4 of the shear 17; the movable blade 5 of the shear 17 then cuts the weft tails sucked by the nozzle 15.

[0051] The suction nozzle 15 can have an airflow direction close to the weft direction. The weft tails advance with the fabric keeps the air direction trim until cutting and suction.

[0052] In other embodiments of the present invention, the device in FIG. 6 also makes advantageous use of an elastic gripping element 16 on the guiding plane 6 of the weft tails advancing with the fabric 1. The gripping element 16 can be used when an additional thread tension is required before cutting with the shear 17.

[0053] The technical features of the weft threads saving device for weaving machines according to the present invention are apparent from the description above, as are its advantages, such as: [0054] weft color management with standard pick-at-will selector with eight or more colors, as with split selvages; [0055] use of all types of weft threads and possible recycling of recovered tails; [0056] variations in the breadth of the fabric on both sides thereof, while maintaining all the functional details of the textile cycle; [0057] possibility of using standard temples and combs; [0058] full advanced breast beam in full weaving breadth; [0059] elimination of the management of split selvages and related tension controls; [0060] reduction of the rapier travel ensuring better productive performance of the machine; [0061] limited cost of production, as compared to traditional solutions, in relation to the achieved benefits.

[0062] The invention thus described and disclosed herein is susceptible to many changes and variants, all falling within the scope of the inventive concept of the appended claims.

[0063] Furthermore, all construction details can be replaced by technically equivalent elements.