A METHOD AND APPARATUS FOR AUTOMATICALLY PRODUCING TUBULAR KNITWEAR ITEMS PROVIDED WITH AT LEAST A BRACE, SHOULDER STRAP, LOOP AND THE LIKE, AND PRODUCTS OBTAINED THEREBY

Abstract: The invention relates to tubular knitwear items complete with shoulder straps (20, 21), braces and various openings for legs or arms, manufactured without the usual cutting and sewing operations. Through the appropriate selection of needles, in accordance with the jaquard design and to the operating cycle of the knitting machine, the invention allows the separation and automatic programmed resumption of knitted courses for defined areas or zones, thereby obtaining at least a complete opening or brace, formed by at least a simple or double welt, or even multiple, edges, depending on circumstances. Lastly, the invention eliminates the current necessary cut and sew operations and the consequent, usual and costly fabric scrap.

Description: A Method and Apparatus for Automatically Producing Tubular Knitwear Items Provided with at least a Brace, Shoulder Strap, Loop and the Like, and Products Obtained thereby Technical Field the present invention relates to a method and apparatus for automatically producing tubular knitwear items provided with at least a brace, shoulder strap, loop and the like, and products obtained thereby. The introduction of "full electronic" circular knitting machines with differentiated diameters has attracted the industry's interest since the versatility of these machines allows to produce a wide range of semifinished tubular items such as bras, panties, dresses, trousers, skirts, teddies, swimsuits, technical items and more. Currently, the tubular items mentioned in the premise are completed with laborious cutting operations along pre-defined lines and assembled with delicate and costly sewing operations. In Figures 1 and 2, the knitted tube 1 (panty and undershirt) provided with double elastic edge with two layers 2, as a rule is cut along the dashed lines in order to define the front part A relative to the rear part P, whereupon the resulting edges Ξ are sewn together, in correspondence with the extremities 3. These operations inevitably entail considerable quantities of scrap which, although variable according to size and model, often exceed 20% of the initial quantity of fabric: a permanent waste which significantly impacts on the final costs of the products. In general, due to some inherent technical limitations, among them the lack of shoulder straps, loops, sundry openings for legs and arms, or specifically designed openings, also multiple, with functional and aesthetic purposes, most of the aforementioned knitwear items systematically require laborious and costly additional finishing operations such as cutting and sewing with considerable wastage of fabric impacting continuously and permanently on production costs. As the experts in the field well know, in theory, with the alternating motion of the cylinder of the needles it is possible to obtain a wide range of knitted items provided with different appendices or shapes; but the long production times added to the considerable masses of the needle cylinders with greater diameters, make this hypothesis excessively costly or technically impracticable. As far as it is known, the Italian patent no. 1288310 by the same holder provides for different embodiments concerning shoulder straps, loops or braces, or sundry openings for legs and arms. Beside this patent, Italian Patent no. 1255008 by the same holder (schematically shown in Figs. 7-8-8A-8B-9 referenced herein). Briefly, the patent contemplates the manufacture of circular knitwear items characterised by fabric areas with differentiated growth caused by the exclusion of a limited number of needles, alternated relatively to the adjacent ones, for instance 1:1, or 2:2 - 2:1 and the like. However, such solutions have technical limitations and additional costs due to the complex and costly mechanisms for gripping and transporting the fabric from one part of the cylinder to the other. Aims of the invention The present invention aims at significantly reducing or eliminating altogether some of the aforesaid technical and productive limitations to obtain automatically knitwear items complete with shoulder straps, braces or various openings, preferably without fabric waste, with original economic, technical, aesthetic and commercial purposes . All this stated, a main aim of the present invention is to provide a method and the related apparatus for manufacturing tubular knitted garments provided with at least a shoulder strap, loop, brace and the like, preferably complete and also padded, produced automatically with the continuous motion of the cylinder of the needles. A further aim consists of a method and related apparatus for manufacturing said tubular knitted items, provided with one or more sufficiently ample openings, with double welt or edges, also padded, for aesthetic or functional purposes, obtained directly in the circular machine during manufacturing and hence without the additional cutting and sewing operations. Another aim is to provide a method and the related apparatus for the production of tubular knitwear items with braces or complete openings provided with simple or multiple edges, i.e. with multiple layers, produced both with the aid of the plateau or other needle bed, or with just the selection of needles or sinkers. Another aim is to provide a method for manufacturing tubular items provided with braces whereon preferably tubular sleeves complete with cuffs are subsequently sewn. Lastly, a further aim is to provide a method and the related apparatus for manufacturing tubular items also in 00/71794 two layers or concentric, having at least a shoulder strap, brace, or loop or edges with multiple layers obtained during production, with the fixed and prolonged exclusion of groups of needles also alternating or by groups, with other needles still operating, according to the teachings of Italian Patent no. 1288310 and of patent application no. CO-97-000003, entitled "Sundry Enhancements and Innovations in the Production of Socks and Other Knitwear" by the same inventor. Additional aims are apparent from the description, embodiments and accompanying drawings, by themselves or in mutual combination, in addition to the final claims. The features of the invention and advantages which derive from it shall become more readily apparent from the following description of embodiments, provided by way of example and can be applied advantageously to most knitwear and hosiery circular machines. Disclosure of the invention the above mentioned aims are substantially achieved by a method for automatically producing tubular knitwear items provided with one or more shoulder straps, loops or braces, in knitting machines provided with at least a needlebed. The method comprises the following steps: producing a first length of tubular knitted fabric having a cylindrical shape and ending with a last stitch course, producing a second length of tubular fabric by automatic and programmed resumption of the predetermined number of needles of the needlebed in the knit forming process (the second length starts with a first stitch course) and producing at least a third length of tubular knitted fabric. The method according to the present invention is 00/71794 5 characterized in that the third length of tubular knitted fabric comprises at least an active portion and at least a passive portion connected to the active portion, the passive portion being produced by excluding a predetermined number of needles of the needlebed from the knit forming process for a predetermined time interval. Advantageously, the method according to the present invention comprises also the step of varying the knit density in the active portion with respect to the passive portion of the tubular knitted fabric. Accordingly to the present invention, during the phase of producing the second length of tubular knitted fabric, the method comprises also the production of at least a side opening, the active portion surrounding at least partially a boundary of said side opening and the passive portion being said boundary of said side opening; in particular, during the step of producing said second length of tubular knitted fabric the needles excluded from the knit formation process are adjacent with each other or alternatively are chosen according to a predetermined sequence along the needlebed. Brief description of the Drawings The description will be made with reference to the accompanying drawings, in which: figure 1 shows a tubular knitted fabric in which a panty to be cut or sewn is defined by dashed lines; figure 2 shows a tubular knitted fabric in which an undershirt to be cut or sewn is defined by dashed lines; figures 3, 4 and 5 show the progressive transformation of a knit tube into a bra provided with shoulder straps (figure 4 is an enlarged view of a particular of figure 00/71794 3); figure 6 shows a brief or a panty obtained with the method according to the present invention; figures 7, 8 and 9 technically show the sequences for the production of the three-dimensional knit frills Bi; Figures 8A and 8B show schematically the knit effects produced with the aforementioned internal frills Bi, arranged horizontally and diagonally; figure 10 technically shows an "embossed" or cellular stitch structure; figures 11, 12 and 13 show the so-called "tuck stitch" of a needle in a knitting machine; figures 14, 15 and 16 and 17 show the missing stitch or welt of the needle of figures 11, 12 and 13; figures 18, 19, 20, 20A, 20B, 21, 22 and 23 show various embodiments of knitwear items obtained in accordance with the invention; figures 24, 25 and 26 technically show the sequences for the discharging of the last knit loops; figure 27 shows schematically a latch-opening device in a knitting machine in accordance with the present invention; figure 28 is an enlarged view of a latch needle; and figures 29, 30 and 31 show double edges produced in accordance with the present invention, padded with additional threads. Description of the Illustrative Embodiment For some embodiments, the present invention exploits the teachings of Italian Patent no. 1255008, whose main features have been sintetically discussed hereabove. Contrarily to the known art, a portion of impulses or commands usually directed to the needles is not sent to a portion thereof, according to a defined layout or programme conforming to the original design. This causes the exclusion from the stitch formation process of the needles lacking inputs or commands; this exclusion, if total and with defined areas, produces the floating threads FF instead of the stitching M, Fig. 7. Said floating threads FF can be further manipulated with the use of some working needles, Fig. 8, duly distanced, with the dual purpose of reducing the length of the floating threads and to create - if need be - interesting stitch interlacing or three-dimensional internal frills or flounces Bi. Hence, the invention is also obtained by further manipulating the aforesaid floating threads FF transforming them into stitched fabric produced only with a part of the needles present in the involved areas or zones . For instance, only even needles or alternating pairs of needles will be excluded; i.e. in groups of three operating needles followed by one or more excluded needles, and so on. The simultaneous presence of working needles, alternating with excluded needles, Fig. 8, for defined areas and/or for a time which may even be relatively long, Fig. 9 (corresponding to a high number of stitch courses), is the sufficient and necessary condition for the manufacture of an original knitted fabric, formed by the working needles and related loops AD but interrupted and still interlaced with the excluded needles and loops AP, in order to produce a closed knit flounce, with two layers or fabrics Bi, Fig. 8, inside the usual tubular fabric. This growth of supplementary stitching or frill Bi is characterised on the front of the knitted fabric by a perfect suture caused by the elongation of the loops or stitches of the needles AP not working and hence excluded from the manufacture of the aforesaid frill, which is repeatable or variable in height and width. The three- dimensional frills Bi are particularly attractive also arranged in small repeated diagonals, so as to accentuate anatomic comfort and support or modify the usual appearance of the jersey fabric. The features of the invention and the advantages which derive from it shall become more readily apparent from, the following description of embodiments provided by way of example and can be applied advantageously to most circular machines. These results are easily achieved according to the invention, and purely with descriptive and non limiting purposes, most of the description concerns a "full electronic" type of machine (for instance the Santoni model SM 8 TOP machine) . The invention is initially implemented by setting up a work cycle and a jacquard design, i.e. information directed or precluded to the needles and a jacks or other elements concurring directly or indirectly in the production of the fabric, by means of a usual graphic station or control or memory devices or by means of electro-mechanical, magnetic, optical apparatuses, and other means suitable for the purpose in any way. Thus the stitched tube of Figure 3 starts from the double edge 2A with a continuous selection of alternating needles, for instance the odd ones, or with all needles operating and with the aid of the hooks of the plateau (not shown) . After completing the aforementioned double edge by releasing the hooks of the dial or by suturing stitches with the start of operations by the needles previously excluded, for instance the even ones, the production of stitched fabric continues in the area 30, characterised by knit structures able to improve the resistance of the fabric against unravelling (Figs. 13-14). Therefore, the automatic release or discharge of the loops B, Fig. 23, or stitched by the needles A along the lines or openings 5 - 5A, of Figs. 3 and 4, is preceded by a preparatory phase with the possibly automatic variation of the stitching density, together with the use of suitable additional threads, also elastomeric or thermo-adhesive, the latter subject to partial melting interlacing also to the adjacent loops during the subsequent finishing. Thus, the release or discharge of the individual loops or stitches of a part of the needles can be conducted according to multiple requirements or technical or textile factors. In a first preferred embodiment, if the machine and work cycle is set to the "zero" position, all feeds and yarn feeders are excluded and the hooks U of the needles A whereon the last loops B are engaged, are preferably below the working plane of the sinkers. After this readying phase (not shown) only the programmed needles, as a rule grouped and adjacent, are sent to the ascent cam without yarn in a single feed to lift completely. The maximum elevation of the aforesaid needles produces two important results: all the latches of the needles are opened automatically and are positioned above the last loops, still engaged between the needles and the sinkers . The subsequent phase entailing the descent of the same needles is shown in Figures 24 - 25 - 26. The needle A starts to descend and the last loop B, adhering against the stem of the needles, inserting under the latch L starts to close it automatically and progressively, Fig. 25. The latch L, fully closed, serves as a "bridge" for the same loops B which are then definitively detached, as in Fig. 26. In this phase also the sinkers P move progressively and radially backwards following the arrow F, synchronously with the descent motion of the needles A. The progressive discharge of the loops B from the involved needles produces a continuous horizontal opening in the direction of the courses in the stitched tube, so at this point the fabric tube is engaged only to a part of the needles of the cylinder while the remaining disengaged needles, temporarily lacking stitches or loops, must necessarily start the production process anew. In accordance with the invention such needles are then selected and again progressively directed on at least an ascent cam according to a predefined sequence such as 1:3 (one needle operating and three excluded) or 1:1 and the like, until the gradual ascent of all needles which take up a new yarn. During this ascent, the needles A still with the latches L closed, find on the obligated path a latch opener device AL for their forced opening. The described procedure is shown schematically in Fig. 27: the latch L is still against the hook U inside which a metal latch- opening tip AL is automatically positioned until the latch L is opened and upset in the direction of the arrow F . Fig. 28 shows a plan view of a fraction of the cylinder CYL, rotating in the direction of the arrow F. The hook U, adhering to the latch L, finds on the obligated ascent path the latch opener AL, inserted for that purpose. The method for forming the stitching starts again with a simple or double edge or welt, i.e. one with single or double fabric, or else, depending on the item being produced, after the intervention of the mechanical or pneumatic elements serving as latch openers (in other embodiments the latch is opened by means of an appropriate blast of compressed air coming from above, or by means of a thin foil able to be inserted between the hook and the tab or yet other means) . In accordance with the invention, the total and programmed interruption of the stitch-forming process of a part of the needles of the cylinder, for defined zones or areas of stitching, followed by the automatic and programmed resumption of the stitch-forming process preferably of the same needles and defined stitching areas, produces the total and controlled separation of at least two theoretically consecutive stitching courses, in turn characterised in that the former represents the last row of the produced stitching, whilst the second represents the first stitching row produced preferably with the same needles, after the aforesaid interruption. For purposes of the present invention, only a part of the needles housed in the rotating cylinder is destined to release or discharge the respective last stitching loops. Following the set work cycle and jacquard drawing, the needles are programmed to operate in a group, i.e. a variable plurality of adjacent needles, directly related to the amplitude of the envisioned opening. Figure 4 shows an enlarged view of a particular of figure 3: the double initial elastic edge (11) is marked with reference numeral 2A. 5A indicates the produced opening; 8 and 9 the stitching edges adjacent to the opening, which are also provided with double layer edges, indicated as 10, similar to edges 20A, and obtainable in various manners: with the usual needles or hooks of the plateau selected for the purpose, or with a part of the needles of the cylinder, for instance the odd needles AD of Figure 8 which continue to produce stitching whilst the even needles AP hold the respective last loops. As a result, an internal frill Bi (Fig. 8) is produced, or stitching with three-dimensional growth widely adjustable in amplitude, height and diagonally. In regard to the double welt DB, Fig. 30, in accordance with the present invention, it can also be padded internally by the insertion of additional threads Y, fed and variously patterned between the two layers during the construction of the welt and prior to its definitive closure or suture. Alternatively, the internal padding is obtained with three-dimensional stitching effects such as terry cloth and the like, or with the production of the aforementioned frills Bi, Fig. 31, also repeated, placed inside the double welt DB. The tubular knitwear item 1 of Fig. 5, a tee-shirt, teddy or simple bra, is provided with the double edge 2A engaged only in correspondence with the forward central part Y (and rear part, not shown) . In accordance with the invention, said edge 2A is detached or separated, then opened laterally with the two loops produced automatically, which, lifted according to the arrows FI and F2, assume the shape and the functions of the shoulder straps 20 - 21. The reference DB indicates the double edge produced after the formation of the brace 20. The stitching areas indicated as 11 - 13 - 14 can be produced with different knit structures, such as the ones shown in Table 2, according to current needs and variables . In particular, the central area 12 is structurally and functionally connected to the upper part Y of the braces 20 and 21 or to the other adjacent areas, able to support, by themselves or in mutual relationship, in a widely differentiated manner, the breasts. In another preferred embodiment, Fig. 6, the knitwear item 1 represents a panty obtained from a tubular fabric with double elastic edge 2A, having a functional opening 03 provided with double edge DB together with the lateral edges 5 - 5A produced in accordance with the invention. In this circumstance, too, the bottom stitching can be produced with different knitted structures, besides the open-work T, obtained with the aforementioned techniques. The present invention is at the origin of the products in Figure 18: the bodice-bra 1 and the skirt 2 which are respectively characterised by the presence of the upper shoulder straps or supporting braces 20 - 21, which may also be multiple, or by the lateral loop 22 similar to the lower openings 22 A in correspondence with the hips. Yet again, the fabric of the aforesaid items is characterised by the knit structures obtainable in accordance with the present invention, also with a plurality or prevalence of tuck stitches, Figs. 10 - 11 - 12 -13, or welts, Figs. 14 and 15, together with one or more internal knit flounces Bi, Figure 8-8A-8B-9. Fig. 19 shows a panty sewn in correspondence with S and provided with elastic upper edge 2A which is divided in two parts on the hips, together with other double edges or borders DB. The central open-work part T is further characterised by flounces in areas Bi. Figure 20 shows another knitwear item falling within the scope of the invention; the tubular item 1 is provided with shoulder straps or braces 20-21 obtained according to the invention and completed with additional sleeves Ml - M2 preferably tubular, provided with at least a double edge DB and sewn in correspondence with the suture lines S - S2. Alternatively, such sleeves are provided with two double edges, one of which is destined to be sewn on the exterior part of the shoulder strap or brace: thus with a simple circular seam practically free of cuts and the deriving scrap, a finished article is obtained lacking longitudinal or visible seams. Figure 20A schematically shows a tubular item 1 provided with the upper and lower double edges DB, with an upper knit area MS with open-work interlacing T ending before the elastic edge BE in median position; followed by the lower knit part MI. In correspondence with the horizontal lines A, opposite, parallel and adjacent to the aforementioned edges DB, the loops are released to create the shoulder straps - braces described previously. Subsequently, the lower part MI is folded inwards into the upper part MS so that the resulting knitwear item is formed by two concentric fabrics, provided with a variable number of shoulder straps or braces (as shown in figure 20B) , or a knitwear item provided with shoulder straps 20 - 21, lower elastic edge BE and an original 00/71794 15 effect of open-work knit, superposed to a bottom stitching differing substantially in yarn, colour or interlacing, to create contrasting effects. Another application of the invention is shown schematically in Fig. 21; the knitwear item 1, indifferently a sock, or a technical item or other item, is provided with a single loop or double upper edge DB, or, as in Fig. 22, is provided with at least two support braces instead of the usual elastic edge. The knitwear item 1 of Figure 23 also falls within the scope of the present invention. The interruption and programmed resumption of the knit formation process produces the single neck loop 2 (rear 2A) together with the central opening 03 provided with the double edges DB in correspondence with the chest. The method as described is further completed in Figures 29, 30 and 31 of Table 4. In particular, Figure 29 is a partial view of the knit tube 1, provided with the usual welt or two-layer edge DB. Fig. 30 is a variation whereby inside said double edge additional padding threads or fibres Y have been inserted, with the presence of the internal waste . Lastly, in Fig. 31 the aforementioned double edge is padded with a plurality of internal frills Bi and characterised by an external waste W. The broad flexibility of the invention allows to substantially modify the shape and the functions of at least a portion of current knitwear items with the results described herein. The present description, necessarily limited, provides persons versed in the art with margins of innovation which fall within the scope and aims of the present invention.

Claims: 0/71794 16 Claims 1. A method for automatically producing tubular knitwear items provided with one or more shoulder straps, loops or braces, in knitting machines provided with at least a needlebed, comprising the following steps: - producing a first length of tubular knitted fabric having a cylindrical shape and ending with a last stitch course; - producing a second length of tubular fabric by automatic and programmed resumption of said predetermined number of needles of the needlebed in the knit forming process, said second length starting with a first stitch course; and - producing at least a third length of tubular knitted fabric, characterized in that said third length of tubular knitted fabric comprises at least an active portion and at least a passive portion connected to said active portion, said passive portion being produced by excluding a predetermined number of needles of the needlebed from the knit forming process for a predetermined time interval. 2. A method as recited in claim 1, charachterized in that comprises also the step of varying the knit density in the active portion with respect to the passive portion. 3. A method as recited in claim 1 or claim 2, wherein the phase of producing said second length of tubular knitted fabric comprises the production of at least a side opening, the active portion surrounding at least partially a boundary of said side opening and the passive portion being said boundary of said side opening. 4. A method according to anyone of the precceding claims, wherein during the step of producing said second length of tubular knitted fabric the needles excluded from the knit formation process are adjacent with each other. 5. A method according to anyone of the preceeding claims, wherein wherein during the step of producing said second length of tubular knitted fabric the needles excluded from the knit formation process arechosen according to a predetermined sequence along the needlebed. 6. A method for manufacturing tubular knitwear items, characterised in that said items are provided with one or more shoulder straps or loops or braces, produced automatically with the continuous motion of the cylinder of the needles, by the gradual interruption of the knit formation process of a group of preferably adjacent needles, for defined knit areas smaller than 360°, followed by the automatic and gradual resumption of the knit formation process, preferably of the same needles or defined knit areas, after the intervention of mechanical or pneumatic elements with latch opening functions, for the total and controlled separation of at least two stitch rows theoretically consecutive and superposed, even partially; said courses being characterised in that one represents the last course of the stitching already produced whilst the other one represents the first course of stitching produced after the aforesaid interruption. 7. A method as claimed in claim 1 for manufacturing tubular knitwear items provided with one or more openings or through holes for aesthetic or functional purposes, preferably obtained without cutting and sewing operations . 8. A method as claimed in claims 1 - 2 characterised in that the said shoulder straps, braces and various openings are fitted with edge(s) having simple or multilayer fabric. 9. A method as claimed in claims 1 - 3 characterised in that said edges are produced with the needles of the cylinder and with the aid of the plateau' s hooks or additional needle bed, or with only part of the needles of the cylinder to produce internal frills Bi with the proper selection of alternating needles. 10. A method as claimed in claims 1 - 4 characterised in that on the shoulder straps, braces, loops and openings are sewn additional sleeves preferably tubular, i.e. free of longitudinal seams and provided with at least an edge, also double. 11. A method as claimed in claim 5 characterised in that the knitwear items are produced with machines fitted with compound needles, which resume the stitch-forming process without latch openers. 12. A method as claimed in claim 1 and other claims characterised in that the discharge of the loops by a part of the needles takes place only progressively in at least one feed without yarn. 13. A method as claimed in claim 1 and other claims characterised in that the stitch-forming process of the already excluded needles is preceded by the intervention of latch-opening devices and resumes only progressively with selected needles also in alternating order, in at least a feed provided with yarn. 14. A method as claimed in claim 1 and other claims characterised in that the discharge of the loops of a part of the needles is preceded by one or more courses, formed also by tuck stitches or welts, variable electronically by means of the related motorised cams, preferably with the insertion of at least an additional thread, which can also be elastomeric or thermo-adhesive. 15. A method as claimed in claim 1-7 characterised in that the discharge of the loops of a part of the needles takes place by means of the total lowering of the needles themselves without the new yarn, under the working plane of the sinkers, synchronously with the radial removal thereof. 16. A circular machine for manufacturing knitwear items as claimed in claim 1 and in the following claims, characterised by and comprising at least: a needle bed or cylinder rotating against stationary cams or vice versa; a complete working feed provided with one or more movable yarn feeders the selection of the needles able to control the elements concurring in the formation of the stitching according to a work cycle or jacquard design; the stitch- forming cams adjustable also individually with the aid of the computer; a device for opening the latches of the needle on command; a system for drawing the fabric; also provided with a dial fitted with selectable needles or hooks, in addition to the usual pneumatic device for aspirating and cutting the threads. 17. A circular machine as claimed in claims 1-11 and other claims, characterised in that it is provided with at least two needle beds able to transfer the related loops between the needle beds for the production of knitwear items which may also be tubular, provided with shoulder straps, braces, loops and/or various openings.

Inventors: SCIACCA FRANCO, SCIACCA, FRANCO
Applicants: SCIACCA FRANCO, SCIACCA, FRANCO
Application year: 2000
Main classification: D04B1
IPC codes: D04B1, D04B9