A METHOD AND DEVICE FOR PRODUCING AUTOMATICALLY SHAPED TUBULAR KNITWEAR ITEMS AND PRODUCTS OBTAINED THEREBY

Abstract: The invention relates to tubular knitwear items (1) suitably shaped or modeled without the usual cutting and sewing operations and preferably without using elastic yarns. According to the jacquard design and/or to the work cycle of the textile machine, the invention enables the production of differentiated-growth fabric in specific areas or zones by the programmed exclusion of loops or knitted courses and the simultaneous production of exceeding stitches or inner frills (Bi), thus obtaining a programmed three-dimensional deformation of the knitted tube according to manufacturing needs.

Description: A method and device for producing automatically shaped tubular knitwear items and products obtained thereby Technical Field The introduction of "full electronic" circular knitting machines with differentiated diameters has attracted the knitting industry's interest since the versatility of these machines allows to produce a wide range of semi-finished tubular items, such as for instance bras, pants, dresses, trousers, skirts, teddies, swimsuits, technical items, and more . As is generally known, from the technical-textile point of view said items can be modeled or shaped only partly, since current manufacturing techniques, partly incisive, cannot model the various anatomic portions in a complete, pleasant and satisfying way, as is required by the large number of sizes . This manufacturing difficulty, on the one hand, obliges producers of textile machines to manufacture a large series of tubular machines with very close diameters and fineness degrees, so as to reach a higher precision in the graduation of the final extensibility of the garment, and therefore of the user's comfort. On the other hand, in order to make up for the reduced capacity of shaping or modeling suitably and automatically said items in various sizes with a reduced number of diameter and fineness degrees, knitwear manufacturers are forced to use very expensive elastomeric yarns to a greater extent, i.e. highly "elastic" yarns which can suitably hug or compress anatomic portions. The high cost of said yarns permanently and continuously affects general manufacturing costs, and considering the excessive and suffocating compression, above all in hot climates, the solutions offered by said elastomeric yarns is not always optimal. Aims of the present invention The present invention aims at reducing to a high extent or at wholly eliminating some of the above-mentioned technical and manufacturing limitations, so as to produce automatically tubular knitwear items without longitudinal seams, suitably modeled with original economical, technical, aesthetic and commercial purposes. A main aim of the present invention consists in providing a method for the production of suitably shaped tubular items, automatically produced with the continuous motion of the needle cylinder. A further aim consists in a method for the production of tubular knitwear items, equipped with one or more internal frills Bi and with two-layer welts or rims. An additional aim consists in providing a method for the production of tubular items made of two layers or concentric fabrics and produced continuously, both associated to a common welt, even a double one, said welt being produced by means of both the dial or other needle bed, and the selection of alternated needles. Another aim consists in providing a method for the production of tubular items with two concentric layers, at least one of which has the function of a shaped bra. Further aims result from the description, examples and enclosed drawings, per se or in combination one with the other, together with the final claims. Disclosure of the invention The above mentioned aims are substantially achieved by a method and device for producing automatically shaped tubular knitwear items, and products obtained thereby, according to the appended claims. The features of the invention and the advantages deriving thereof are more evident thanks to the following non limiting description of embodiments provided by way of examples, and advantageously apply to most of circular knitting machines. Brief Description of the Drawings The description will be made with reference to the accompanying drawings in which: - figure 1 is a front view of a fabric having frills Bi made only with odd needles AD, with even needles AP not operating; - figure la shows a needle A, usually housed within the bed or cylinder (not shown) , on whose stem the underlying fabric and the inner frill Bi are still engaged; - figure lb is a view similar to figure la with an "open" frill Bi; - figures 2 and 2a technically show the technical pattern for the production of the three-dimensional knit frills Bi; - figure 3 is a perspective view of the needles carrying out the sequences for the production of knit frills Bi; - figure 4 shows a knitted tube scarcely shaped according to the prior art; - figure 5 shows a knitted tube strongly shaped; figures from 6 to 12 show different embodiments of women' s clothes shaped and conformed to the body by the inner frills Bi, variously arranged; - figure 13 shows a garment 1 made of two concentric layers continuously produced; - figure 14 shows a swimsuit 1, with two concentric layers only in the upper trunk and breast portion. Description of the Illustrative Embodiments The characteristics of the invention and the advantages resulting thereof will be more evident from the following description of embodiments provided by way of example, and can be advantageously applied to the majority of circular machines . These results can be easily reached according to the invention, and to mere descriptive non-limiting purposes, a great part of the invention relates to a modern circular machine of the "full electronic" type. The present invention partly refers to the teachings contained in the Italian patent no. 1255008 belonging to the same proprietor, schematically shown in figs. 1-2-3. In a few words, said patent relates to the production of circular knitwear items characterized by fabric zones with differentiated growth due to the exclusion of a given number of needles, alternated with respect to the adjacent ones, for instance 1:1, or 2:1 - 2:2 and the like. Contrary to the rules, during the fabric-building process a great part of inputs or commands usually directed to the needles is not sent to a part of the latter, following a given pattern or program according to the original design. This results in the exclusion of the needles without inputs or commands from the knitting process: said exclusion, if total and related to specific zones, causes floating yarns instead of the knitted fabric. Said floating yarns are then handled by means of some operating needles A, fig. 1, suitably spaced, with the double purpose of reducing the length of floating yarns and of creating interesting knitted structures, that is to say the inner three- dimensional frills Bi, fig. 1. Therefore, the invention is carried out by handling said floating yarns transformed into knitted fabric, the latter being produced only with a part of the needles which are present in the concerned areas or zones. For instance only even needles AP, fig. 1, will be excluded, or alternated pairs of needles, i.e. three-needle operating groups followed by one or more excluded needles, and so on. The simultaneous presence of operating needles alternated with excluded needles, (figs. 1-3), in specific zones and/or for an even relatively long time (corresponding to a suitable number of knitted courses, fig. 2), is the sufficient and necessary premise for the manufacture of a particularly knitted fabric, built by operating needles and corresponding loops AD, though interrupted and still crossed to excluded needles and loops AP, so as to produce the closed knitted frill with two layers or cloths Bi, ' fig. 1, within the usual knitted tube. The technical pattern of the frill Bi in figure 2 shows that only the odd needles Al, A3 and the following produce fabric, whereas the even ones, A2, A4 and the following are not operating for a large number of courses: from no. 1 to no . . The perspective view of figure 3 shows the excluded even needles A2, and the following, alternated to the odd needles Al, A3 and the following, with the corresponding last loops or stitches B. Such fabric growth or additional frill Bi is characterized on the plain side of the knitted fabric by a perfect seam due to the stretching of the loops or stitches of non- operating needles AP, which are therefore excluded from the building process of said frill, whose height and width is repeatable or variable. Said three-dimensional frills Bi are particularly efficient in horizontal and diagonal directions and, if suitably placed or repeated, they can help the support of anatomic portions such as breast, abdomen, glutei. Generally, a lot of knitted clothes are finished with long cutting operations along pre-established lines and then assembled with difficult and expensive sewing operations. On the other hand, some of the tubular items mentioned in the introduction are shaped to a small extent by using different structures and fabric thicknesses, so as to define one or more fabric portions or zones with respect to others, i.e. to suit them as much as possible to the shape of the human body. In the example known from the prior art shown in figure 4, the initial knitted tube 1, provided with a double welt with two layers 2 and 3, produced without using elastomeric yarns, is shaped to a limited extent by using different structures and fabric thicknesses along the hatched areas indicated with S. In the following figure 5 the knitted tube shows bents or strongly accentuated or modeled areas, indicated with SI, which can be usually obtained by means of cutting and sewing operations, or by using so-called elastic yarns. In a first preferred embodiment the invention is firstly implemented by preparing a work cycle or jacquard design, i.e. direct and/or precluded inputs to needles and/or jacks and/or other elements contributing directly or indirectly to the knitting process, by means of a suitable graphics workstation and/or control and/or storage devices, or by means of electromechanical, magnetic, optical apparatus, and other similar means suitable to said purpose. According to the invention the knitted tube 1 of figure 6 begins in a known way from the double welt 2 with a continuous selection of alternated needles, for instance the odd ones, or with all needles in an operating status and with the help of the jacks of the dial (not shown) . After completing said double welt by releasing the dial hooks or the stitch seam by operating the previously excluded needles, e.g. the even ones, production goes on in a usual way for a suitable number of knitted courses, preferably of jersey fabric. On the breast, according to the jacquard design and its corresponding program or work cycle, the textile machine produces fabric with differentiated growth, said fabric being characterized by symmetrical horizontal and/or diagonal lines formed by inner frills Bi, already shown in fig. 1, so as to define and shape the knitted cups for the breasts and to gradually reduce the diameter of the knitted tube. In practice, the knitting process is characterized by the simultaneous production of loops or single stitches contributing to the formation of the knitted tube, variously interrupted by loops or stitches contributing only to the production of said inner frills Bi . Fig. 6 shows along the trunk and back a series of frills Bi with variable width and depth, which can suitably reduce the fabric growth so as to shape it to the small size of the waist or belt. Towards the pelvis said frills Bi tend to decrease until they completely disappear. The production of item 1 goes on with a suitable number of knitted courses and the remaining frills Bi on the legs have mainly aesthetic functions. Eventually, the manufactured item 1 is completed with a double welt 3 in the usual way. According to the invention the programmed interruption of _ _ the fabric-building process by a part of the cylinder needles on knitted courses or ribs, i.e. on pre-established knitted zones or areas, causes the structural "deformation" of the knitted tube according to the jacquard design or set work cycle. The tubular knitwear item 1 of fig. 7, in which the trouser is obtained by the following cutting/sewing operation, is produced with a machine having a more suitable diameter and/or fineness, and therefore it does not require any excessive shaping operations, thus obtaining the necessary narrowing on the belt with a reduced use of frills Bi. To additional purposes, i.e. to increase a well-defined anatomic comfort, it is provided for the frills Bi, which are also indicated with ZSV in the abdomen area. In the embodiment of figure 8 the knitwear item 1 is obtained by the usual initial knitted tube provided with the usual double welts, also elastic welts 2 and 3. According to the invention said knitted tube is shaped or modeled by means of long diagonal frills Bi, suitably arranged, which also have an important aesthetic and commercial function. The embodiment shown in figure 9 is a garment 1 largely characterized by the use of frills Bi, which, suitably arranged, also purposely lift a portion of the lower welt 3, indicated with arrow F. Considering the variants resulting from productive or technical-textile factors, the upper welt 2 can also be lowered, a satisfying result obtained without the usual expensive cutting-sewing operations . In figs. 10-11-12 the very tight dress 1 is variously characterized by the presence and arrangement of frills Bi . According to the invention it is possible not only to vary to a wide extent the degree of adherence of the clothes produced, but the programmed structural deformation of the knitted tube is integrated, when necessary, by the stylistic search for a pleasant arrangement of said frills, with the advantageous result of integrating useful and functional aspects according to commercially appreciable aesthetic criteria. The above-mentioned figures show the clothes indicated with 1 in aesthetically and functionally different embodiments. For instance, in fig. 12 the large number of frills Bi placed on the back increase the degree of local compression, whereas in figure 11 the part indicated with 4 is made of jersey fabric with a higher degree of elasticity and more shaped than the adjacent areas, which are characterized by a large number of frills Bi. The garment of fig. 12 is particularly characterized by a plurality of suitably arranged frills and by a triple lower double welt 3. Figure 13 shows another knitwear item falling within the framework of the invention: the tubular item 1 is made of two concentric fabrics joined by a common double welt 2. The manufacturing process normally begins from the inner double welt 3A, and therefore from the inner fabric IF, and goes on as far as the upper double welt 2, obtained by means of the dial jacks or alternated needles only. After releasing the said jacks, the knitting process goes on with the production of the outer fabric 1 as far as the lower double welt 3. The outer fabric 1 is wider and may have a different length, color, yarn, structure (also with open work) and/or double welt 3, and it covers, even only partially, the underlying inner fabric, or vice versa. In further detail, the inner fabric IF, having the function of a teddy, is characterized by a usual initial double welt 3A with variable height, if necessary joined or sewn on the crutch, followed by a suitable number of knitted courses as far as the series of frills Bi for compression or abdominal support ZSV. From the hips and as far as the upper double welt 2 the inner knitted tube IF undergoes first a rapid narrowing and then a gradual and continuous widening to shape the upper portion of the trunk, both effects being due to the large number of long frills Bi suitably arranged. Eventually, small frills Bi are placed between and around the breasts to shape the breast. The framework of the present invention also includes the knitwear item shown in figure 14, which schematically shows a swimsuit 1 provided with the upper double welt 2 directly connected to the inner knitted fabric IF having functions of a shaped bra with a plurality of frills Bi, which are present on the whole item. Also in this case the manufacturing process preferably, though not necessarily, begins from the double welt 3 and goes on producing the inner fabric IF as far as the upper double welt 2; therefore, after the usual release of the dial's jacks the fabric goes on and ends on the inguinal portion. After the knitting stage, the inner part IF, i.e. the shaped bra, is bent inwards, so that the resulting knitwear item is made of two partially overlapping concentric fabrics . The large number of frills Bi, beyond resulting in the desired anatomic conformation, greatly contributes to improve the final aspect of the item. With particular reference to the tubular items shown in figures 13 and 14, considering fashion trends and other factors which often change consumers' tastes, the invention also describes and claims the implementation of knitwear items, even of the inside-out type, i.e. designed and carried out so as to stress the three-dimensional effects of the so-called inner frills Bi, which, placed outside and possibly also opened or crumpled, fig. IB, produce an original variety of textile, aesthetic and functional effects. The opened frill Bi is obtained when, at the end of said frill, the corresponding needles discharge the last loops and the fabric therefore tends to close or crumple on itself . With reference to tubular items with two concentric layers, the invention also claims its different use, characterized in that said items can be worn and shown both normally and inside out, an important detail from the technical-textile point of view, above all in presence of fabric produced with colored yarns and with the plating or "vanise" technique, or if one wants to stress the transparent effect between the bottom fabric IF, which is substantially different from the one lying above as far as yarn, color or structure are concerned, and the top fabric being made, also partially, of so-called "open-work" or transparent yarns and/or structures. The present description, though necessarily limited, provides people skilled in the art with wide possibilities of improvement all falling within the framework of the invention.

Claims: Claims 1. A method for producing automatically shaped tubular knitwear items (1) in circular knitting machines provided with at least a needle-bed, characterized in that it comprises the following steps: producing a first length of tubular knitted fabric having a cylindrical shape and ending with a last knitted course; excluding from the knitting process a predetermined number of needles (A) chosen according to a predetermined sequence in at least a first portion of said needle-bed, corresponding to a first portion of knitted tube; producing a second length of tubular knitted fabric, including at least a first portion of knitted tube, corresponding to said first portion of the needle-bed, having a differentiated growth of knitted courses and loops with exceeding stitches or inner frills (Bi) , and at least a second portion of knitted tube, to obtain a programmed three-dimensional deformation of the knitted tube; and reintroducing, after a predetermined time interval, said predetermined number of needles (A) of the needle-bed in the knitting process and producing a third length of tubular knitted fabric. 2. Method according to claim 1, characterized in that in said in step of excluding from the knitting process a predetermined number of needles (A) , the excluded needles (A) are chosen according to a predetermined sequence in at least two separated portions of said needle-bed, corresponding to at least a first and a second portion of knitted tube. 3. Method according to claim 2, characterized in that said two separated portions of needle-bed, corresponding to a first and a second portion of knitted tube, are disposed symmetrically with respect to the needle-bed. 4. Method according to any of claims 1-3 characterized in that said steps of excluding from the knitting process a predetermined number of needles (A) , producing a second length of tubular fabric and reintroducing said predetermined number of needles (A) in the knitting process, are repeated during the knitting process of a knitted tube by progressively excluding and reintroducing in the knitting process a different predetermined numbers of needles (A) chosen in different portions of the needle- bed for each knitted course. 5. Method according to claim 4 in which each different portion of the needle-bed, in which is chosen the predetermined number of needles (A) to be excluded, is selected, for each knitted course, adjacent to preceding portion, in order to obtain frills (Bi) disposed transversally along the knitted tube. 6. Method according to any of the preceding claims characterized in that said steps of excluding from the knitting process a predetermined number of needles (A) , producing a second length of tubular fabric, reintroducing said predetermined number of needles (A) in the knitting process and producing a third length of tubular knitted fabric are repeated along the knitted tube to obtain a programmed three-dimensional deformation of the knitted item (1) . 7. Method according to claim 6 in which said steps of excluding from the knitting process a predetermined number of needles (A) , producing a second length of tubular fabric, reintroducing said predetermined number of needles (A) in the knitting process and producing a third length of tubular knitted fabric are repeated by excluding said predetermined number of needles (A) the same portion of the needle bed for each knitted course, to obtain the programmed three-dimensional deformation in a corresponding portion of the knitted tube. 8. Method according to any of the preceding claims, for producing tubular items (1) obtained by circular knitting machines in particular, preferably equipped with a second bed or dial with jacks or needles (A) , characterized in that said tubular items (1), preferably produced with the continuous motion of the needle cylinder, are suitably shaped and modeled without the usual cutting and sewing operations and preferably without using elastic yarns, according to the jacquard design and/or work cycle of the textile machine. 9. Method according to claims 1 or 8, characterized by the production of fabric with differentiated growth of courses and/or loops or predefined areas by means of the programmed exclusion, even partial, of loops and knitted courses and the simultaneous, even partial, production of exceeding stitches or inner frills (Bi) , for a predetermined time interval corresponding also to an elevated number of knitted courses, i.e. from 30 to 60 courses, to obtain the programmed three-dimensional deformation of the knitted tube, according to the jacquard design or to the corresponding operating program or work cycle. 10. Method according to any of the preceding claims characterized in that said predetermined number of needles (A) excluded from the knitting process are preferably alternated with respect to the adjacent ones, for instance 1:1, or 2:1 - 2:2, and the like. 11. Method according to claim 8, characterized in that, contrary to the rules, during the knitting process a great part of inputs or commands usually directed to the needles (A) is not sent to a part of the latter, following a jacquard pattern or design, or according to an operating program or pre-defined work cycle. 12. Method according to claims 1 or 8 for producing tubular knitted items (1) characterized by and comprising at least: an initial double welt (2) followed by a suitable number of knitted courses as far as a second double welt (3) followed by a final waste; said knitted courses being at least partly produced according to a design or pattern and corresponding work cycle in which a part of the needles (AP) , preferably alternated, for instance the even ones, is excluded from the fabric-building process, whereas the other alternated needles (AD) , for instance the odd ones, which are still operating, produce loops forming frills (Bi) within the knitted tube. 13. Method according to any of the preceding claims, characterized in that at the end of said frills (Bi) the corresponding needles (A) completely discharge the last loops of the frills (Bi), according to a jacquard design or operating program or work cycle, in order to obtain open or crumpled frills (Bi). 14. Method according to any of claims 8-13, characterized in that the discharge of the last loops on part of the needles (A) is carried out only progressively in at least a feed without yarn, at least temporarily. 15. Method according to claim 14, characterized in that the fabric-building process of the excluded needles (A) is preceded by the intervention of latch-opening devices and begins again only progressively with selected alternated needles (A), in at least a feed with yarn. 16. Method according to any of the preceding claims characterized in that said knitwear items (1) can also be turned inside out, i.e. designed and carried out so as to stress also the three-dimensional effects of inner frills (Bi) . 17. Method according to any of the preceding claims for producing tubular knitwear items (1) with two layers, characterized in that preferably the top or outer fabric is partially made of so-called "open-work" or "transparent" yarns and/or structures, therefore distinguishing from the underlying fabric, which is substantially different. 18. Knitwear items (1) as obtainable by a process according to any of the preceding claims. 19. Knitwear item (1) according to claim 18. characterized by the presence of two preferably concentric layers, joined by at least a common double welt (2), also closed by releasing loops with suitable needles (A) or jacks housed in the dial. 20. Knitwear item (1) according to claim 18 characterized by the presence of one or more single or double, upper and lower, rims or welts (3), also partially lowered or lifted. 21. Knitwear item (1) according to claim 18 having two layers of variable length, characterized by the simultaneous presence of front and reverse knitted zones, also produced with colored yarns and by using the plating or "vanise" technique. 22. A circular knitting machine, for producing knitted items (1) in general, even technical items (1), characterized by and comprising at least: a needle bed or rotary cylinder versus fixed cams or vice versa; a complete working feed provided with one or more moving yarn feeders; preferably electronic needle selection for controlling the elements involved in the knitting process according to a work cycle and/or a jacquard design; cams for the making of the fabric which can be also individually adjusted by means of motors and computer; a device for opening needle latches upon actuation; a fabric drawing system; said machine being also equipped with a dial with selectable needles (A) or jacks, beyond the usual yarn suction and cutting device.

Inventors: SCIACCA FRANCO, SCIACCA, FRANCO
Applicants: SCIACCA FRANCO, SCIACCA, FRANCO
Application year: 2001
Main classification: D04B1
IPC codes: D04B1