MXPA00012831A - Method and device for closing the toe of a tubular article on a knitting machine - Google Patents

Abstract

A method is described for the production of a tubular knitted article on a circular knitting machine, in which a needle cylinder knits said tubular article (M) beginning at an initial end and finishing at a final end. At the end of the knitting of said tubular article, the latter is partly released from the needles (5), engaged by transfer members (21, 23) and then released completely from the needles and transferred to means for closing said second end.

Description

METHOD AND DEVICE FOR CLOSING THE LOWER REBORDE OF A TUBULAR ARTICLE IN A TISSUE MACHINE BY POINTS DESCRIPTION Technical Field The present invention relates to a method for the production of a knitted tubular article, with a closed end, for example such as a sock or stocking, a sock, a tubular part for the production of tights for ballerina, or the like. More specifically, the invention relates to a method of the aforementioned type in which the tubular article is produced on a circular knitting machine with a circular plate or needle cylinder, and in which the end is closed therein. machine than that in which the article was woven, subsequent to the knitting by points of this article. The invention also relates to a device for closing the end of the knitted tubular article directly on the machine with which the article was woven.

State of the art In the production of tubular articles knitted by stitches, such as stockings, socks, tubular parts for ballerina meshes and the like, tubular articles are normally knitted by stitches beginning at an initial end and ending at a final end on a cylinder of needles. The tubular article produced in this manner has two open ends, one of which must be closed by sewing or some other suitable method. The article with its open ends is normally released from the needle plate or cylinder of the weaving machine and transferred to a sewing machine where, sometimes with manual, partial intervention, the article must be correctly placed and the end that is going to be Then it must be fed to a sewing machine. As is often the case, if the article is not symmetrical but has, for example, a heel, it must first be properly oriented before the seam is placed, so that the seam is correctly oriented relative to the heel. This involves a large contribution of labor and therefore high costs. This process is time-consuming and expensive due in part to the need to provide machinery for placing and sewing the items that have been produced in a separate weaving machine. In order to eliminate these problems, a method and a device (see European patent EP-A-0, 592, 376) for closing one end, ie the toe, of the tubular article directly on the plate have been suggested. or circular needle cylinder of the weaving machine. In this known method the tubular article is knitted starting at the end with the elasticized cuff and continuing to knit all the way to the edges which are correctly joined together to form the closed toe of the article. This known method is exactly complex and requires a dot-knitting machine that equates with specially formed cloth-forming members, which also considerably increase control difficulties. In addition, the seam is produced on the outside of the article instead of on the inside, as it could be more desirable and as it usually happens in systems in which the seam is carried out far from the weaving machine. Methods and devices have also been suggested in which the toe of the article is closed as the initial step in a knitting process, which therefore begins with the closed end and ends at the open end comprising the elasticized cuff. Methods and devices of this type are described, for example, in WO A 95/31595, WO A 95/34702 and WO A 97/04153.

Objectives of the invention An initial objective of the present invention is to provide a process or method for producing a knitted tubular article in which the tubular article is obtained with its lower end closed without requiring manual intervention to guide it. Yet another object of the present invention is to provide a method of the type described above capable of closing the tip or lower end of the tubular article by a very simple sewing system and in which a seam can be produced on the inside of the article. Yet another object of the preferred embodiment of the present invention is to provide a method for closing the lower end or tip of the foot in a tubular article directly on the weaving machine., which weaves the article by points. It is also an object of the invention to provide a very simple device, with a limited number of special fabric-forming elements, capable of closing the lower end of a tubular article without difficulties of orientation of the article. The object of a preferred embodiment of the invention is to provide a device capable of closing the lower end of the article as the final step in the knitting process, eliminating the need to transfer the tubular article from the knitting machine to the knitting machines. sew.BRIEF DESCRIPTION OF THE INVENTION These other advantages advantages, which will become clearer to those skilled in the art upon reading the following text, are achieved with a method for the production of a knitted tubular article with a closed lower end on the circular knitting machine, in which a circular needle plate or cylinder forms the tubular article starting at an initial edge or an end, and ending at the end or end tip to be closed. According to the invention, the method is characterized in that at the end of the knitted fabric of the tubular article, the latter is partially released from the needles, coupled by the transfer members and then completely released from the needles and transferred to the means for closing the tip or lower end. In this way the article that is coupled by the transfer members before being completely released from the needles, reaches the means for closing the lower end or tip in a correctly oriented position without the need for manual intervention. In a particularly advantageous embodiment of the invention, the method involves the following steps: - turning the tubular article with the inner part outward at the end of the weaving process by points of the horizontal passes or rows on the needle cylinder, and then having to fit it on the transfer members, - transferring the article below the needle cylinder, closing the second end of the tubular article, and flipping the tubular article back to the right. The seam or closure of the tip or lower end can take place in a machine outside the circular machine, or within the circular machine itself, where the sewing systems, for example a small sewing machine, can be accommodated. In order to flip the article with the inner part out in a simple and effective way, and then close the tip or end with a seam, which, once the production process has concluded will be located on the inside of the tubular article instead of on the outside, a particularly advantageous embodiment of the invention employs a tubular element coaxial with the needle cylinder and extending downwardly from an upper edge located at level with or slightly below the needle cylinder. During the knitting process, the tubular article grows downwardly within the tubular element. At the end of the knitting process, while the tubular article is still partially coupled on the cylinder needles, the transfer members move coaxially relative to the tubular element and on the outer part of this element in order to couple the article on the edges of the fabric, between the upper edge of the tubular element and the needle cylinder, and then pull the article down along the outside of the tubular element, turning it with the inner part outward as it passes over the upper edge of this tubular element. At the end of the transfer process, the tubular article is now flipped with the inner part out, and is still coupled by the lower portion of the tubular element, with its end that is to be closed free below the lower edge of the element tubular, where a closure means is placed, for example, a sewing machine of a type known per se.

Once the tip or bottom end has been closed, the item must be turned upside down a second time and in this way in practice it is flipped to the right, for example, returned to the position in which it was originally knitted by stitches by the cylinder of needles. The same transfer members can be used again for this purpose. In a particularly advantageous embodiment, after the lower or tip end of the article has been closed, one of the transfer members is moved to approximately coaxial with the tubular element and below it, and is then extended so that it enters the interior of the tubular member, taking this tubular article whose closed end pushes in front thereof . The result of this is that the tubular article is flipped with the inner part out once more around the lower edge of the tubular element. From this element the article, now turned to the right, can be extracted by pneumatic means of a type known per se. The device according to the invention comprises a circular needle bed, for example, a needle cylinder, for knitting the article in points, and is characterized by transfer members capable of coupling the tubular article at the end of the weaving process. points and before the item is completely released from the needle cylinder needles; the transfer members transfer the end of the article to be closed to the closing means, preferably placed below the needle cylinder or outside the circular machine. A possible and particularly advantageous embodiment of the device according to the invention employs a tubular element coaxial with the needle cylinder and extending downwards from an upper edge downwards of the needle cylinder. The tubular element has a diameter smaller than the needle cylinder and the transfer members are movable on the outside of the tubular element, parallel to its axis, in order to couple the tubular article to the end to be closed, and transferred downwards, causing it to turn upside down as it passes over the upper edge of the tubular element. The transfer members preferably include perforation means that couple the tubular article by penetrating the knitted fabric by stitching forming the article at the edges of the fabric that are suitable for fastening. Because these fabric edges are cut and discarded during the closing of the article, this does not damage the final article. The transfer members can be two in number and placed in diametrically opposite positions with respect to the axis of the tubular element. In a particularly simple and advantageous embodiment, the transfer members are equipped with a telescopic elongation system, for example pneumatic or hydraulic means for extending a tubular structure. This does not exclude the use of different means, such as slides that travel along the accommodated tracks parallel to the axis of the tubular element. Also, advantageously, the transfer members can also be able to execute a movement perpendicular to the clamping movement and transfer the tubular article, so that at least one of the transfer members can also be used to turn the tubular article with the part internally out a second time (so that it closes to the right). For this purpose it is advantageous if at least one of the transfer members can be moved alternately outside or inside the tubular element extending down below the needle cylinder. The second overturning of the tubular article with the inner part facing out (eg, to the right) is carried out by placing the transfer member approximately coaxial with the tubular element and then extending the transfer member axially within the tubular element, taking with it the closed end that forms the lower end of the tubular article, which by this means is turned with the internal part outwards as it passes over the lower edge of the tubular element. This does not, however, preclude the option of using separate members for the second time to flip the tubular article with the inner part facing outward, ie to the right; for example, an additional slider placed in an intermediate position between the transfer members. Furthermore, although it is less advantageous in terms of production and reduction of work, it is also conceivable that the tubular article is turned to the right away from the knitting machine by points. Other features and advantageous embodiments of the method and device according to the invention are listed in the appended dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS A clear understanding of the invention will be obtained from the description and the accompanying drawings, the latter showing a practical, non-restrictive example of the invention. In the drawings: Figure 1 shows a schematic front view of a machine according to the invention; Figure 2 shows a side view in the direction indicated by II-II in Figure 1; Figure 3 shows an enlargement of the tubular element and the transfer members as they hold the article before it is completely released by the needle cylinder in a front view similar to the view of the figure 1; Figure 4 shows a section on IV-IV as marked in figure 3; Figure 5 shows a plan view on V-V as marked in Figure 3; Figure 6 shows a view similar to the view of Figure 3 in a subsequent step in the process; Figures 7 and 8 show a sectional view and a plan view on VII-VII and VIII-VIII as marked in Figure 6; Figure 9 shows a step after that illustrated in Figure 6; Figure 10 shows a section marked X-X in Figure 9; Figures 11, 12, 13, 14, 15 and 16 show front views of the successive positions of the article, of the transfer members and of the sewing machine during closure of the tip or lower end of the tubular article; Figures 17 and 18 show a detail of the fastening system of the transfer members in two different positions; Figures 19 and 20 are a front view and a side view of a different embodiment of the fastening systems of the transfer members; Figure 21 is a schematic view of the seam stitched along the edges of the tip or bottom end of the tubular article; Figures 22 to 28 show a different embodiment of the tubular element under various conditions during the knitting cycle, where Figures 22 and 23 are sections along lines XXII-XXII and XXIII-XXIII of Figure 24, respectively; and Figure 29 is a cross section along the line XXIX-XXIX of Figure 23; and Figure 20 is a plan view along line XXX-XXX of Figure 23.

Detailed description of the preferred embodiment of the invention Figures 1 and 2 show general views of a circular knitting machine produced with the device of the present invention. The number 1 is a general reference for the cylinder for the needles, which contains a needle cylinder 3, which is a circular needle plate. The cylinder is of the rotating type. The subsequent figures show the needles 5 of the needle cylinder 3. The cylinder 1, the needle cylinder 3 and the cloth forming members (not shown) for operating the needles are of a type that is known per se and will not be described with additional detail here. Extending downwards from the circular needle plate 3 is a tubular element 7 which is essentially coaxial with the cylinder 1 and with the circular plate 3. The tubular element 7 has an upper edge 7A and a lower edge 7B. The upper edge 7A and the lower edge 7B are enlarged and rounded for the reasons that will be described later. Connected to the lower end of the tubular element 7 is a suction sleeve 9 which pneumatically removes the tubular articles as they are formed in the tubular plate 3. The sleeve 9 is vertically movable as shown by the double arrow f9 (figures 1 and 2). ) and for this purpose it is connected to a pair of piston and cylinder actuators 11. The sleeve includes an openable portion 10, opened by a cylinder and piston actuator 12. The tubular element 7 is supported by three pairs of rollers 13A, 13B accommodated at angular intervals of 120 °, as is visible in figures 5 and 8 in particular. The rollers 13A, 13B of each pair are located near the upper flared edge 7A and the lower widened edge 7B, respectively. In addition, around the tubular element 7 there are three stepped seals 15. These are also displaced 120 ° from one another and are located between the pairs of rollers 13A, 13B. Each stepper 15 is controlled by its own actuator 17 to be able to move towards or away from the outer surface of the tubular element 7. In this way, the steppers 15 are able to immobilize the tubular element 7 under pressure, and thus serve as auxiliary support means in conjunction with the pairs of rollers 13A, 13B, or even they may also move backwardly therefrom to leave their outer surface free. This arrangement makes it possible for the tubular article generated by the plate 3 to be flipped with the outer part facing out and transferred to a sewing machine, as will be explained below. The pisacosturas 15 can also be omitted. Below the tubular element 7 is a sewing machine having the general reference 19: this is of a type known per se and is used to close the lower ends of the knitted tubular articles by stitching them. The sewing machine can be of the type normally used in the machines for sewing the tips or lower ends of the articles that usually come from the knitting machines. As explained above, in the prior art these sewing machines are located on machines physically separated from the knitting machines by circular points on which the articles are formed. The transfer members 21, 23 run down the outer side of the tubular element 7. These consist of extendable telescopic tubular elements equipped at their upper ends with fastening means in the form of hooks, needles or the like which are shown in detail in FIG. Figures 17 and 18. For each transfer member 21, 23 there is a hook 25 with a closure element consisting of a slide 27 pushed in the closed position by an elastic member 29. In Figure 17 the hook member is shown in FIG. the open position, with the slide 27 down and the elastic member 29 compressed, while figure 18 shows the slide 27 closed, limiting against an inclined surface 25A on the hook 25 and the expanded elastic member 29. Figures 19 and 20 show a modified embodiment of the transfer members, in which the hook 25 is replaced with a 25X bolt needle mounted on the upper end of the telescopically extendable system. Around the needle 25X is an extraction member 26 operated by the cylinder and piston actuators 28. The extraction member is raised as shown by the arrow f26 when the transfer member is used to turn the tubular article with the inner part out a second time, once again the tip or lower end is sewn. The telescopic elongation of the tubular system of the transfer members 21, 23 is caused by the pumping of a fluid under pressure in the cavities of the tubular elements through the connectors 31 (see figures 4 and 7 in particular). The fluid pumped under pressure inside the telescopic tubular members produces elongation upwards, and the retraction is originated by means of a flexible line 33 which can be wound on a reel 37 correspondingly (see figures 3 and 6 in particular). The transfer members are carried by a carriage 39 which moves on the guide bars 41 fixed to the structure of the machine (see in particular figure 1). The transfer members 21 and 23 are hinged to the carriage 39 and controlled by a cylinder and piston actuator 43 in such a way that they are able to pivot about the horizontal axes which basically coincide with the axes of the line 33 rewinding the reels 37, for the reasons that will be explained later. Through the guides 41, the transfer members 21 and 23 can be moved relative to the axis of the tubular element 7 to carry out their functions which will be described with reference to figures 3-16. The device described in this way works very much in the following manner. Figure 3 illustrates the final step in the knitted fabric of the tubular article M by the needles 5 of the circular plate 3. The knitted fabric of the article M starts at the end Ml which, for example in the case of a , It is endowed with an elastic fist. The knitting action is produced by rotating the circular plate 3 of the needles 5 and the ends with the fabric by points of the end M2 which must be closed to form the tip or lower end of the article. During knitting of the tubular article, the shaped portions corresponding to the heel of the article, or other special portions, may be formed as in the normal knitting technology. In the position shown in Figures 3, 4 and 5, the tubular article M has been completed and is almost completely released from the needles 5 of the circular plate 3. Only some of the needles, for example ten or twenty needles, are coupled to the article M in two diametrically opposed zones, as can be observed in particular in the plan view of figure 5. In this phase the circular plate 3 can be stationary or it can still be moving at a very slow speed. The transfer members 21 and 23 have been extended upward to put the hooks 25 in engagement with the fabric of the portion adjacent to the end M2 of the tubular article M. The hooks 25 have penetrated the article and the article is held on the hooks by the closing of the slide 27 of each of the transfer members 21 and 23. In the position shown in Figures 3, 4 and 5, the article M is therefore still coupled on the circular plate 3 of the needles 5, and also coupled by the transfer members 21 and 23 which then, as will be described, transfer the article to the sewing machine 19. In the position shown in figures 1, 2 and 3 the suction sleeve 9 has been removed by a downward stroke of the actuators 11 from the tubular element 7 to allow the transfer of the tubular article M to the sewing machine 19. During the knitting step before this, however, the knitting to 9 was connected to the lower edge 7B of the tubular element 7 to generate a slight vacuum within the tubular element 7, the purpose being to stretch the article M into it as it is knitted by stitches. Once the hooks 25 and the slides 27 have firmly fixed the article M to the transfer members 21 and 23 in at least two points, the article can be completely separated from the needles 5 of the circular plate 3, which, for this purpose completes its own rotating movement. It is now possible to transfer the article M to the sewing machine 19. The start of this step is illustrated in figures 6, 7 and 8. The transfer members 21 and 23 are gradually retracted by rewinding the lines 33 on the reels 37. This pulls the article M downwards from the outer wall of the tubular element 7 following the hooks 25. Consequently the article M is pulled out of the tubular element and flipped with the inside outwards as it passes over the rounded flared edge 7A of the tubular element 7. The operation continues until the position shown in Figs. 9 and 10 is reached, where the tubular article M now completely with the inner part outward as compared to the position it had during knitting, is coupled by its upper portion around the tubular element 7, which it covers from the outside, while the lower end M2 (for example the last end formed by the circular plate 3) is as below, is still coupled between the transfer members 21 and 23 and is lower than the lower edge 7B of the tubular element 7. To allow the article M to be moved from inside the tubular element 7 to the outside of the latter, and also to allow the article M to slide all the way down the outer surface of the tubular element 7 towards the position of figures 9 and 10, the clamping members 15 which retain the tubular element in position are retracted by the actuators 17 of so that the tubular element 7 remains suspended only by the three pairs of rollers 13A, 13B. The tubular article thus passes between the rollers 13A, 13B and the outer part of the tubular element 7, and can arrive unobstructed in the position shown in figures 9 and 10. At this point it is necessary to insert the lower end M2 of the article , which will be sewn to create the tip or bottom end of the article, inside the mouth of the sewing machine 19 (which has been omitted in the presentation of figures 3-10 to simplify the drawing). For this purpose, the provision can be made so that the sewing machine 19 executes a movement towards the axis of the tubular element 7.

For simplicity, however, it is preferred to give at least one of the transfer members 21, 23 a pivot movement to pull the end M2 of the tubular article M towards the mouth of the sewing machine 19. For simplicity of construction and also to ensure sufficient tensioning of the end M2 when sewing commences, provision is made for both transfer members 21 and 23 to pivot about the horizontal axes under the action of the cylinder and piston actuator 43. This pivoting movement widens the transfer members 21, 23 outwardly in the position of FIG. 11, with the consequent insertion of an edge of the terminal end M of the tubular article M into the mouth of the sewing machine 19. The latter it thus begins to operate by sewing, in a manner known per se, the edges of the lower end M2 and cutting the final portion of the knitted fabric in points in a manner known per se. One type of seam that can be used to close the M2 end of the tubular article M is shown schematically in Figure 21, where the knitted fabric of the article is shown schematically in the form of two edges placed together, without any indication of the individual curls from which they are composed. The operation of the sewing machine 19 pulls the article 9 towards the sewing machine as can be seen in figures 12 and 13. In the last figure, the transfer members 21 and 23 have been moved backwards in the vertical position. At the termination of the closing of the tip or lower end formed by the M2 end of the article, the latter is released by the sewing machine 19 and must be flipped again with the outer part out a second time, ie flipped to the right for return it to its previous position. For this purpose the transfer members 21, 23 are made to travel along the guides 41 until the transfer member 23 is approximately coaxial with the tubular element 7, as seen in Figure 14. The subsequent extension of the limb Transfer 23 by the telescopic elongation pushes the article M upwards to the tubular element 7 as seen in figure 15. The article then slides out of the outer surface of the tubular element 7 and is turned from the internal part outwards according to it passes under the lower edge 7B widened and rounded, of the tubular element, until it reaches the final position illustrated in figure 16. In the position of figure 16, the article M is again in the position it had during its weaving by stitches and the seam formed by the sewing machine 19 is on the inside of the article, having been flipped the last one with the inner part out it is that the union will be made. After the tip or bottom end of the article M has been stitched and before said article begins to be inserted into the tubular element 7 by the transfer member 23, the suction sleeve 19 is raised by the actuators 11 until it it is near the lower edge 7B of the tubular element 7, but at a distance from the latter so that the article can still pass through it. The openable portion 10 is opened to allow insertion of the transfer member 23. In this position sufficient vacuum is generated within the tubular member 7 to pull down a new tubular article undergoing formation, and to stretch the tubular article M whose tip or lower end has just been closed. As seen in Figure 16, a second article M 'is present being formed at the upper end of the tubular element 7, the knitted fabric which is started while the other article is being stitched and flipped with the inner part out a second time around the lower edge 7B of the tubular element 7. When the tubular article M whose tip or lower end has been closed is again completely inside the tubular element 7, the transfer member 23 can be removed, the openable portion 10 of the suction cup can be closed and the suction sleeve 9 itself can be set completely against the lower edge 7B of the tubular element 7. As soon as the transfer member 23 has been retracted, the article M with the closed tip is removed by suction inside the suction sleeve 9. The vacuum created inside the sleeve and inside the tubular element 7 maintains the tension on the new article M2 as it is being formed. The machine is ready to carry out a new closing cycle of the tip as soon as article M2 has been completed. Figures 22 to 30 show a developed embodiment of the device according to the invention. The corresponding elements are designated with the same reference numbers as in the previous figures. According to the embodiment of Figures 22-30, the tubular element 7 is provided with four perforated areas, arranged symmetrically about the axis of the tubular element. Two of the perforated areas are shown in Figure 22 and designated 101 and 103. Each area 101, 103 is provided with a larger central hole 101A, 102A. Two oscillating suction boxes 105, 107 are arranged side by side on the outside of the tubular element 7. Each suction box 105, 107 can pivot about a horizontal axis 105A, 107A, carried by the stationary frame 111. Each suction box 105, 107 is provided with an upper inlet opening 105B, 107B accommodated in correspondence of the perforated areas 101 and a lower exit opening 105C, 107C. In correspondence of the entry openings 105B, 107B, each oscillating suction box 105, 107 is provided with pins 113, 115 aligned with the holes 101A. The two oscillating suction boxes 105, 107 can take two extreme positions: in the first position (figures 24, 25) the inlet openings 105B, 107B are kept clear of the outer surface of the tubular element 7, and so are the spikes 113, 115 with respect to the holes 101A. In the second position the upper inlet openings 105B, 107B are in contact with the outer surface of the tubular element 7 and the pins 113, 115 are inserted into the holes 101A. In this second position, the pins 113, 115 vertically support the tubular element 7 and the outlet openings 105C, 107C are in communication with the interior of the tubular element 7ways the perforated areas 101. Below the stationary frame 111 are accommodated two boxes sliding suction 121, 123 to slide forward and backward relative to the tubular element 1. The two sliding suction boxes 121, 123 each have an inlet opening 121B, 123B and two outlet openings 121C, 123C. The inlet openings 121B, 123B are accommodated at the same level as the perforated areas 103 of the tubular element 7 and in correspondence of the same two pins 125, 127 are accommodated, which can be engaged within the holes 103A. The two sliding suction boxes 123, 125 can take two positions: in a first position (figures 26, 27) the two sliding suction boxes 123, 125 are free of the tubular element 7 and the pins 125, 127 are decoupled from the holes 103A. In the second position (figures 24, 25) the two boxes 123, 125 are in contact with the outer surface of the tubular element 7. In this second position, the pins 125, 127 are inserted into the holes 103A and support the tubular element 7 , while the outlet openings 121C, 123C are in communication with the interior of the tubular element 7 via the perforated areas 103. The suction boxes are in communication with a vacuum line by means of the outlet openings 105C, 107C, 121C , 123C. The device shown in Figs. 22 to 30 operates as follows: During the knitting of the tubular article M, the oscillating suction boxes 105, 107 and / or the sliding suction boxes 121, 123 are coupled with the interior surface of the element. tubular 7 in order to generate a certain degree of vacuum in these, which sucks the article M which is knitted by points inside the tubular element 7 and stresses it. Once the knitted tubular article M has been completed (Fig. 22), the transfer members 21, 23 engage the upper edges of the article M near the needles 5 (Figs. 23, 24). The oscillating suction boxes 105, 107 are oscillated away from the outer surface of the tubular element 7, while the lower sliding suction boxes 121, 123 are in engagement with the outer surface of the tubular element 7 and keep the interior thereof low vacuum conditions. At the same time, the pins 125, 127 support the tubular element 7. The transfer members 21, 23 are retracted and moved in the downward direction as in the previous example, thus pulling the article M out of the tubular element 7. The article is turned with the inner part outwards as it passes over the upper edge 7A of the tubular element 7. Since the upper oscillating suction boxes 105, 107 are free of the tubular element 7, the knitted tubular article M can slide to along the outer surface of the tubular element 7. As soon as the end Ml of the tubular article M has passed, the perforated areas 101, the oscillating suction boxes 105, 107 are oscillated against the outer surface of the tubular element 7, and the pins 113, 115 are put into engagement with the holes 101A, in order to support the tubular element 7. Correspondingly, the lower sliding suction boxes 121, 123 they are moved away from the outer surface of the tubular element 7, thereby allowing the tubular article M to pass over the perforated areas 103 as it moves towards the sewing machine (not shown). The article M is then closed by means of the sewing machine as previously described. During this operation, the interior of the tubular element 7 is constantly maintained under light vacuum conditions, either through the oscillating suction boxes 105, 107 or through the suction boxes 121, 123. This makes the start possible of the knitting cycle of the subsequent article M2 at a very early stage, as shown in figures 27 and 28. In figure 27, the new article is under formation, while the previous article M is pushed into the tubular element 7 by flipping it with the inner part out the second time. In Figure 29, the completed article M is removed by suction via line 9, while the dot fabric of the following article continues. It will be understood that the drawings will show only an illustrative embodiment purely as a practical demonstration of the invention, while the latter may be varied in its forms and arrangements nevertheless without departing from the scope of the concept on which the invention is based.

Claims (30)

REI INDICATIONS

1. Method for the production of a knitted tubular article in a circular knitting machine, where: a needle cylinder weaves the tubular article beginning at an initial edge and ending at a tip or bottom lower end; at the end of the knitted fabric of the tubular article, the latter is partially released from the needles, coupled with the transfer members and then completely released from the needles and transferred to the means for closing the tip; The method is characterized in that: the article is turned with the internal part outwards after its release from the needles of the needle cylinder; the tip of the article is transferred below the needle cylinder; the tip closes.

2. Method according to claim 1, characterized in that the tubular article is turned to the right again after having closed the tip.

3. Method according to claim 1 or 2, characterized in that: after the termination thereof, the tubular article is partially released from the needles and retained only by some of the needles in two diametrically opposed zones; the transfer members are coupled to the tubular article in correspondence of the two diametrically opposed zones; after coupling by the transfer members, the tubular article is completely released from the needles.

4. Method according to claim 1, 2 or 3, characterized in that the article is formed by the needle cylinder inside a tubular element coaxial with the needle cylinder and provided with an upper edge located below it, and the article is turned with the inside out when pulling one or more edges of the fabric adjacent to the tip, in a direction parallel to the axis of the tubular element and on the outside thereof, in a manner such as to cause the article to come out of the tubular element and be turned with the internal part outwards as it passes over the upper edge of the tubular element.

5. Method according to one or more of the previous claims, characterized in that: the tubular article is knitted on a rotating needle cylinder; when the knitted fabric is finished, the rotary movement of the needle cylinder is decreased or stopped and the tubular article is partially released from the needle cylinder while being held onto it by a small number of needles retaining one or more edges of it; and the tubular article is held by the transfer members at the edges and, after completing the uncoupling of the needle cylinder needle article, the transfer members flip it with the inner part outwards when pulling it downwards.

6. Method according to one or more of the preceding claims, characterized in that the tip or inferred end is closed by a sewing device placed below the needle cylinder.

7. Method according to one or more of the preceding claims, characterized in that the tubular article is turned to the right after the tip has been closed, by the transfer members.

8. Method according to claims 4 and 7, characterized in that one of the transfer members is placed below the tubular element and approximately coaxial therein and the tubular article is turned to the right when pulling it into the tubular element by means of the transfer member , thus turning the article with the inner part out a second time around the lower edge of the tubular element.

9. Method according to one or more of the preceding claims, characterized in that the knitted fabric begins on a new tubular article on the needle cylinder at the same time that the tip of the tubular article is being closed and turned with the internal part facing out.

10. A device for closing the tip of a tubular knitted article, comprising: a needle cylinder for knitting the article, and transfer members capable of coupling the tubular article at the end of the knitting process and before that the article be completely released from the needles of the needle cylinder, characterized by a tubular element coaxial with the needle cylinder, and extending below an upper edge below the needle cylinder, which has a smaller diameter than the cylinder of needles containing the tubular article during the knitting process, the transfer members are movable on the outer side of the tubular element and parallel to its axis in order to couple the tubular article near its tip to be closed and transfer it downwards, causing it to turn with the internal part outwards as it passes over the upper edge of the tubular element.

11. Device according to claim 10, characterized in that the transfer members directly transfer the tip of the tubular article to the closure means placed below the needle cylinder.

12. Device according to claim 10 or 11, characterized in that the closing means comprise a sewing device.

13. Device according to one or more of claims 10-12, characterized in that the transfer members comprise coupling means capable of coupling the tubular article when penetrating the woven fabric by stitches forming said article.

14. Device according to one or more of claims 10-13, characterized in that it comprises two transfer members acting in symmetrical positions with respect to the axis of the tubular element.

15. Device according to one or more of claims 10-14, characterized in that the tubular element has an enlarged and rounded upper edge.

16. Device according to one or more of claims 10-15, characterized in that the tubular element has a broadened and rounded lower edge.

17. Device according to one or more of claims 10-16, characterized in that the transfer members have a telescopic elongation system. * 18 Device according to one or more of claims 10-17, characterized in that it comprises means for flipping the article

• Tubular with the inner part facing out a second time after the tip has been closed.

19. Device according to claims 10 and 18, characterized in that the means for turning the tubular article with the internal part out a second time, comprise a pusher positionable approximately coaxially with the tubular element, the pusher is extendable within the tubular element.

20. Device according to claim 19, characterized in that the pusher is one of the transfer members that is movable perpendicularly to the axis of the tubular element to be positioned either outside or inside the tubular element.

21. Device according to one or more of claims 10-20, characterized in that the transfer members comprise extendable rods that pivot about the axes perpendicular to the axis of the tubular element.

22. Device according to one or more of claims 10-21, characterized in that the tubular element is supported by a plurality of rollers that are coupled to its outer surface, the tubular article being able to slide on the outer surface, between the surface and the rollers.

23. Device according to claim 22, characterized in that it comprises three pairs of rollers, the rollers of each pair are arranged, one near the upper edge and one near the lower edge of the tubular element, the pairs being displaced by approximately 120 ° one of the another around the axis of the tubular element.

24. Device according to claim 22 or 23, characterized in that it comprises additional means for supporting the tubular element, the additional support means being retractable away from the outer surface of the tubular element.

25. Device according to one or more of claims 10-24, characterized in that the transfer members can execute a movement perpendicular to the needle cylinder axis to place the tip of the tubular article in engagement with the sewing means located eccentrically with respect to the Needle cylinder.

26. Device according to one or more of claims 10-25, characterized in that it comprises a suction sleeve associated with, and movable relative to the tubular element.

27. Device according to claims 19 and 26, characterized in that the suction sleeve has an opening approximately coaxial with the tubular element, so that the pusher can pass through it when the tubular element is turned to the right.

28. Device according to at least claim 10, characterized by the movable suction boxes that maintain the interior of the tubular element under a vacuum condition.

29. Device according to claim 28, characterized by two pairs of suction boxes, which are alternatively in coupling or out of engagement with the tubular element.

30. Device according to claim 28 or 29, characterized in that the suction boxes are provided with support means for supporting the tubular element.