AND RESPECTIVE CIRCULAR MACHINE” DESCRIPTION

Field of the Invention

The present invention generally relates to machines for producing knit fabrics and relates in particular to a process and system for closing an end of a tubular manufactured article, directly on a hosiery or knitwear circular machine. State of the art

Hosiery and knitwear circular machines basically comprise a rotating cylinder having at its periphery a plurality of parallel grooves which house the same amount of vertically arranged, i.e. vertically oriented, needles parallel to the generatrix of the cylinder. Alternatively, in so-called double-cylinder machines, there are two rotating cylinders, a lower one and an upper one, both having peripheral grooves and being mounted one above the other so that their respective grooves are aligned with each other. Thus, the needles can be slid into one or the other rotating cylinders, as needed. Each cylinder is rotated and at least one yarn to be knitted is fed to the needles via one or more feeding stations, also known as feeders, combined with the cylinder(s). The needles comprise a so-called hook portion and a latch adapted to close the hook portion in the knit formation step, and are movable between a raised position, an intermediate or restrained position and a lowered position, in response to stresses imparted by cams which are combined with the outer surface of the rotating cylinder so as to be moved close to or away from it, in order to intercept at least one yarn and form the stitches.

Therefore, these machines produce tubular manufactured products whose ends are both open. Specifically, each rotating cylinder may rotate in continuous motion and in reciprocating motion, if portions shaped like a bag have to be produced, such as for example in the case of a sock, the portions intended to be fitted on the heel and on the tip of a user's foot. Usually, a sock is produced starting from its edge and ending with the toe portion.

In recent years, devices which allow, by means of an external sewing or linking apparatus combined with the machine, the edges of an end of the manufactured article to be joined, and specifically the end corresponding to the sock toe at the beginning or at the end of its production, have been developed. This way, an almost complete manufactured article, with the exception of any optional elements to be applied after its production, is obtained, so as to go on to any subsequent steps of dyeing and/or finishing and/or ironing More specifically, systems have been proposed which provide that a collecting device is positioned at the machine cylinder, or in any case at a cylinder in case of double-cylinder machines, at the end of the production of the manufactured article; that the last stitch present on each of the needles of this cylinder is collected by means of this collecting device; that the collecting device is moved away from the cylinder, in order to extract the sock from the machine; that, if necessary, the sock is turned inside out by means of an appropriate pneumatic device, so that its inner surface faces outwards; that the stitches are arranged on supporting members of a sewing head combined with the machine, so that the stitches initially present on one half of the cylinder are each coupled to a corresponding stitch initially present on the other half of the cylinder needles and that each pair of stitches are joined together by means of an appropriate sewing needle belonging to the sewing or linking head. However, these systems are particularly expensive as they require a sewing or linking head equipped with a specific needle and means to move it and to move the sewing head. In addition, this needle has to be necessarily inserted between pairs of supporting members in order to join the stitches they support. Since the space between two supporting members is quite small, this operation is complex and causes the sewing needle and/or supporting members to be undesirably worn. Alternatively, systems have also been proposed in which a bag defining the toe portion is formed at the beginning of the sock production step, after that the rest of the manufactured article is produced and finally the edge of the sock is produced. However, this system was not particularly successful as it was extremely subject to breakages. In addition, the sock obtained has lower quality compared to traditional socks produced from the edge. In fact, since the sock is made in reverse way, i.e. starting from the toe, it has to be ended with a double edge, thus limiting the type of socks that can be produced. In addition, the end part of the yarn remains free inside the edge, with the risk of fraying during the use of the sock, thus ruining the latter. Document W02007/110894A2 relates to a machine for closing from the inside a tubular article, i.e. a sock, the article being produced from the edge and being suctioned upwards by a hollow shaft of the plate of the machine itself that produced it. The article is closed by sewing together two portions of the end part of the article. So the sock, disadvantageously, instead of being produced in the traditional way is constructed upside down, which is an extremely complex operation, and is kept suctioned into a small cavity obtained right for this purpose at a shaft, normally not hollow, of a machine member, so that the machine itself and the normal method of producing the sock have to be substantially modified. In addition, in order to close the sock, instead of the stitches of the last course of the sock, two end edges made up of portions formed by several courses are joined together, thus obtaining a particularly thick seam, which is aesthetically unpleasant, as well as particularly annoying for the user.

Document US2010/319410A1 relates to a device for closing the end of tubular articles of hosiery. For transferring stitches from a first arch of needles to a second arch of opposite needles, the device comprises a semicircular sector which can be overturned and has elements ending in a bifurcation, each of them having a projection adapted to engage an end stitch formed by a corresponding needle and to transfer it to a corresponding needle of the second needle arch. In order to carry out such a transfer, the stitches to be transferred are pneumatically tensioned before their transfer so that they are enlarged in order to be transferred onto the needles. Such a solution, therefore, gives rise to a seam comprising enlarged stitches that not only form unaesthetic holes but can also cause breakage of the seam itself. The stitch to close the toe also includes a sequence of courses of tight stitches, followed by a final course of loose stitches, which further exacerbates the problems mentioned above.

Object and summary of the invention

Object of the present invention is to solve the problems stated above with reference to the known art by proposing a system and a process for closing an end of a tubular manufactured article produced in a traditional way, starting from an edge thereof that is intended to remain open, by means of a circular machine for hosiery or knitwear provided with at least one lower cylinder.

Another object is to propose a system and process that allows the end of a tubular manufactured article to be closed from the inside or outside, while keeping the tubular manufactured article normally arranged in the lower cylinder during its manufacture.

A further object is to propose a system that is not only more economical than known art systems but also involves few modifications to the machine and is less subject to wear.

Yet another object is to propose a system that does not require specific needles, nor external devices, to close the end of the tubular manufactured article.

These objects are achieved by a process for closing an end of a tubular manufactured article, such as a sock, according to claim 1. Specifically, the tubular manufactured article comprises a plurality of stitches of at least one yarn fed to needles which are carried by at least one lower rotating cylinder and are susceptible to vertical movement, and the process provides that the stitch present on at least one half of adjacent cylinder needles is collected, then these stitches are positioned on another half of the cylinder needles, together with the stitches originally present on a second half of the cylinder needles, and a yarn is fed to the needles of the half of the cylinder needles, which carry the pairs of stitches, the yarn having to be processed so as to join the stitches together and thereby close the end of the tubular manufactured article. The lettering "half of the cylinder needles" refers to a plurality of needles adjacent to each other, equal to half of the total number of the cylinder needles.

Advantageously, during its production, the manufactured article is kept, as usual, inside the lower cylinder so that it results to be in its final configuration and not turned inside out. At most, the tubular manufactured article can only be turned inside out once it has been completed, before closing the toe. Preferably, in order to join the stitches, the cylinder is rotated in reciprocating motion to perform at least two semi-rotations in opposite directions.

Preferably, a respective pair of stitches, which are originally carried by needles in positions opposite each other with respect to a diameter of the cylinder, are arranged on each needle of a half of adjacent cylinder needles, and these stitches are joined by knitting, sewing or linking them together directly by means of the cylinder needles which have contributed to the formation of the tubular manufactured article, without using any additional needle or any linking or sewing device external to the machine or otherwise combined therewith. Preferably, the stitches are positioned on the second half of the cylinder needles while keeping these needles in their restrained position, in order to prevent the stitches from being lowered below the needle latch and to then be able to control the needles, as needed.

Advantageously, during the first semi-rotation some needles of the second half of the needles intercept the yarn in a raised position and are interspersed with other needles of the second half of the needles which intercept the yarn in a non-raised position, preferably in a restrained position, while during the second semi-rotation the needles that previously intercepted the yarn in the raised position now intercept the yarn in a non-raised position, preferably in a restrained position, and conversely the needles that previously intercepted the yarn in the non-raised position, preferably in the restrained position, now intercept the yarn in the raised position. This makes it possible to obtain a succession of stitches that are knitted to one another so that they do not become unstitched once the tubular manufactured product is unloaded from the circular machine. To achieve a more robust closure, additional semi- rotational sequences such as the one described above may be performed. In a particularly preferred solution, in the at least two previously described semi rotations a needle intercepts the yarn in a raised position and is followed by a needle that intercepts the yarn in a non-raised position, preferably in a restrained position, followed in turn by a needle that intercepts the yarn in a raised position, and so on according to a so-called 1:1 selection.

Preferably, after the above two or more semi-rotations, at least one semi rotation, in which all of the needles of the second half of the needles intercept the yarn in the raised position, is carried out to unload all the respective stitches and unload from the rotating cylinder the manufactured article, which has a closed end.

Advantageously, once the stitches have been collected from at least one half of the cylinder needles, the tubular manufactured article is extracted from the cylinder and simultaneously turned inside out, so that its inner surface is on the outside and therefore the tubular manufactured article is turned inside out. After the stitches have been coupled and arranged on the second half of the needles, but before the toe closure has been carried out, the tubular manufactured article, in particular the sock, is positioned again into the cylinder though it remains inside out. This way, the aesthetically less pleasant part of the obtained seam and the portion of yarn cut at the end of the seam remain in the inner part of the manufactured article. Therefore, once the obtained manufactured article has been turned inside out to be ready for use, it looks very aesthetically pleasing and particularly strong, especially at its seam.

Preferably, the process involves collecting the stitches of at least half of the cylinder needles by a plurality of transferring members carried by a movable portion of a supporting element. This way, once the stitches have been collected by arranging the transferring members of the movable portion at the needles of the first half of the cylinder, the movable portion is rotated by 180° to bring the respective transferring members at the needles of the second half of the cylinder. The transferring members may be arranged in the same direction as the needles and above them so as to collect from above the stitch carried by a respective needle, or they may be arranged perpendicular to the needles and may be moved radially, so as to be inserted between pairs of adjacent needles in order to collect the stitch from the respective needle.

Even more preferably, the supporting element further comprises a fixed portion that carries the same number of transferring members as the movable portion, and to which the movable portion is fixed so as to be able to perform 180° rotations with respect thereto. This way it is possible

- to collect from each needle of the rotating cylinder the respective stitch by a transferring member of the fixed portion or the movable portion;

- if necessary, turn the tubular manufactured product inside out;

- rotate the movable portion by 180° so that its transferring members are in contact with or at the transferring members of the fixed portion;

- if necessary, move the stitches from the movable to the fixed portion;

- if necessary, rotate the movable portion by 180° so as to return it to the initial position where it is aligned and coplanar with the fixed portion and without stitches;

- transfer each pair of stitches on each transferring member of the fixed portion and, in case, of the movable portion, to a respective needle of the second half of the needles of the rotating cylinder;

- if necessary, arrange the tubular manufactured article turned inside out in the cylinder;

- carry out at least two partial semi-rotations of the cylinder, feeding at least one yarn to the needles in order to close the end of the tubular manufactured article.

The invention also relates to an improved circular machine according to claim 11.

Specifically, the machine comprises a positioning device provided with at least collecting means to collect stitches from a first half of the cylinder needles and position them on the other half of the cylinder needles, together with the stitches which were originally on this half of the needles. The positioning device therefore comprises a number of transferring members equal to at least half of the cylinder needles, arranged to form a semicircle, and means for bringing these transferring members, at first, at the first half of the cylinder needles to collect respective stitches therefrom, and subsequently at the second half of the cylinder needles, to allow the stitches to be moved therefrom to the second half of the cylinder needles. Thus, the two halves of the last course, i.e. the two initially opposed knit semicircles, of an end of the manufactured article are on the second half of the cylinder needles, so that they can be joined by directly using the cylinder needles previously used to make the manufactured article.

Advantageously, therefore, the machine head and the yarn feeding stations are movable between:

- an active position, in which they contribute to the formation of the manufactured article,

- an idle position, in which they are away from the cylinder to allow the positioning apparatus and the respective transferring members to be positioned, and

- back to the active position in order to contribute to close the end of the manufactured article.

Advantageously, the head is combined with the machine so that it can be overturned by an angle sufficient to clear the space above the cylinder; preferably this angle is at least 45°, preferably about 90° with respect to the horizontal direction, or the head is rotated sideways by an angle of at least 45°, preferably about 90°. Preferably, the positioning device comprises a plurality of transferring members whose number is equal to the number of needles of the machine, one half of which is carried by a fixed portion of a supporting element and the other half by a movable portion of the supporting element, wherein the movable portion is combined with the fixed portion so as to be able to rotate by 180° from an initial position, in which it is coplanar to the fixed portion, to a tilted position, in which it is located near or in contact with the fixed portion. Thank to this configuration the stitches can be moved from all the cylinder needles to the transferring members of the fixed and movable portions, the movable portion can be rotated, the respective stitches can be moved, if necessary, to the transferring members of the fixed portion so that two stitches are located on the transferring members of the fixed portion, if necessary the movable portion can be returned to its initial position and finally the pairs of stitches can be moved from the transferring members of the fixed portion to a corresponding half of the cylinder needles. The movements of the stitches from the needles to the transferring members, from the transferring members of the movable portion to those of the fixed portion and from the transferring members to half of the needles are known per se and may comprise pusher elements combined with the positioning device and/or the machine cylinder, to be alternately used in case the stitches have to be moved upwards or downwards.

Preferably, the positioning device further comprises a turner for turning the tubular manufactured article inside out, directly above the machine cylinder, after the stitches have been collected from at least half of the cylinder needles and before these stitches are coupled to a stitch of the other half of the needles. This way, the inner surface of the tubular manufactured article is on the outside, so that the portion of free yarn, which is formed at the end of the joining of its end, remains inside the tubular manufactured article once the latter has been turned again inside out to be used.

Advantageously, the turner comprises a tubular member movable to be at least partially inserted into the tubular manufactured article and suction means combined with said tubular element in order to keep a portion of said tubular manufactured article attached to the tubular element itself during a return travel thereof in which it extracts from the cylinder the tubular manufactured article that is thus caused to be turned inside out. The tubular element may be of the telescopic type in order to reduce the overall dimensions of the turner. Once turned inside out, the tubular manufactured article is arranged back in the lower cylinder to close its end.

In addition, the invention relates to a positioning device for circular machines according to claim 18. Such a positioning device comprises a transferring apparatus operating at the cylinder of a circular knitwear or hosiery machine, for allowing a respective stitch to be collected from at least one first half of the cylinder needles and the stitches collected from at least the first half of the cylinder needles to be positioned on the needles of the other half of the cylinder, together with the stitches previously arranged on this second half of the cylinder needles.

Preferably, the positioning device further comprises a turner integrated with the transferring apparatus for turning the tubular manufactured article inside out, before positioning the stitches collected at least from the first half of the cylinder needles onto the needles of the other half of the cylinder. Advantageously, therefore, the device is structured to allow a pair of stitches of a tubular manufactured article to be positioned on a half of the cylinder needles of a machine, initially in opposite positions with respect to a diameter of the cylinder, with the tubular manufactured article turned inside out, then to return the tubular manufactured article into the lower cylinder in order to, then, join the two edges of an end thereof directly on the machine itself. Preferably, the transferring apparatus has at least one movable portion and one fixed portion, if any, which have each a plurality of transferring members adapted to collect stitches from a respective half of the cylinder needles, and are combined with each other so that the movable portion is susceptible to 180° rotations in opposite directions, with respect to the fixed portion. Brief description of the drawings

However, the invention will be better illustrated in the following description with reference to the attached indicative and non-limiting drawings, in which: figure 1 shows a front view of a circular hosiery or knitwear machine provided with a positioning device according to the present invention, in a normal condition of use, at the end of the production of a tubular manufactured article; figure 2 shows the machine of figure 1 in a second condition of use; figure 3 shows the machine of figure 2 with the positioning device in a working position; figures 4, 5 and 6 show an enlarged view of the machine portion in the frame of figure 3, with the positioning device in three different steps of collecting the stitches of an end of the tubular manufactured article and turning the manufactured article itself inside out; figures 7, 8 and 9 show three subsequent steps needed to couple together the previously collected stitches; figures 10 and 11 show the steps required to transfer pairs of stitches to a half of the cylinder needles; figure 12 shows a view of the machine, similar to that in figure 1 , but with the last stitches of the tubular manufactured article arranged on a half of the cylinder needles; figure 13 shows a schematic view of the cylinder completed with needles; figure 14 shows part of the machine needles during a working step for closing the end of the manufactured article; and figure 15 shows two machine needles in two different positions, which are taken while closing the end of the manufactured article.

Detailed description of the invention

In said drawings, the numeral 1 generically denotes a circular machine for hosiery or knitwear. The machine may be of the type adapted for producing socks or stockings. The figures illustrate, by way of example, a machine of the type with only one cylinder, also called single cylinder machine, but the machine could also be of the double-cylinder type.

This circular machine 1 comprises a base 2, a head 3, at least one main or lower cylinder 4 combined with the base and susceptible of at least partial rotations, defined as travels, in which a plurality of vertically arranged needles 5 are slidably mounted side by side to form a circle, the latter comprising a first semicircle SC1 and a second semicircle SC2 both having the same number of needles, as shown in figure 13. The machine may also comprise an upper cylinder - not shown - combined with the head and mounted above the cylinder 4 and aligned therewith, so that the needles 5 may slide into either of these cylinders in order to make plain or purl stitches. Each cylinder can be selectively operated to rotate with continuous or reciprocating motion, depending on the production steps. For simplicity, the following description will refer to a single- cylinder machine, i.e. a machine equipped with only one cylinder, without excluding that what is described below may also be applicable to a double cylinder machine, i.e. equipped with an upper cylinder too.

One or more feeding stations 6 are combined with the head, for feeding the needles with at least one yarn 7 to be processed, for the production of a tubular manufactured article 8 that consists of a sequence of stitches of at least said yarn, which form a plurality of consecutive courses. The term "course" refers to stitches made in one travel, i.e. one full or partial turn of the cylinder. For producing stitches, usually the needles may comprise a portion referred to as a hook 5' to catch and restrain the yarn to be processed, and a latch 5" to close the hook during stitch formation. Each needle can be selectively brought to:

- a lowered position, in which the hook does not intercept the yarn but unloads the stitch produced in the previous travel,

- a raised position A, in which the hook intercepts the yarn and, as shown in figure 15, brings the stitch made in the previous travel below the latch in order to be able to unload it when the needle is brought to the lowered position, or

- an intermediate position defined restrained position B in which, as shown in figure 15, the hook restrains above the latch the stitch made in the previous travel and possibly intercepts the yarn.

Specifically, the tubular manufactured article may be a sock and is made starting from an edge portion thereof, followed by a leg portion, if any, to be worn on at least part of a user's leg, then by a foot portion, and ending with a toe portion to be worn on the user's toes. At the end of the production of the manufactured article, on the cylinder needles there are the stitches 8" which form the last course 8' of the manufactured article, i.e. the knit turn which forms the terminal end of the manufactured article. The sock remains in the machine cylinder 4 during its production, suctioned downwards by suction means normally provided on the machines of the present invention. Thanks to this, no changes are made to the machine other than those strictly necessary to close its toe.

According to the invention, a positioning device 9 is combined with the machine. Preferably, the positioning device is fixed to the base by means of a support 10 having an arm 11 rotatable about the support itself, in order to move the positioning device between a resting position in which it is shifted sideways with respect to the at least one machine cylinder, as shown in figures 1 , 2 and 12, and a working position shown in figures 3-11, in which it is at the machine cylinder and aligned therewith.

The positioning device 9 comprises a transferring apparatus 12 adapted for collecting from at least one half of consecutive needles of the cylinder needles 5, i.e. from at least one first semicircle SC1, the respective stitches of at least one first half of the last course 8' and for positioning the collected stitches on the other half of the needles of the rotating cylinder, i.e. on the other semicircle SC2, or vice versa, so that each of these needles no longer supports a single stitch but a pair of stitches one of which belonging to the first half of the last course and the other one belonging to a second half of the last course. In other words, the stitches arranged, at first, on the needles belonging to the first semicircle SC1 and forming the first half of the last course are arranged on the needles belonging to the second semicircle SC2, together with the stitches originally supported by the needles of this second semicircle and forming the second half of the last course, so that two stitches 8", initially in positions opposite each other with reference to a diameter D that partitions the two semicircles, result to be on the same needle belonging to the second semicircle, as shown in figure 15. This operation is often referred to as "stitch overturning" and allows the first and second halves of the last course, i.e. the two knit semicircles that make up one end of the tubular manufactured article, to be brought close to each other.

Once the stitches have been collected from the first half of the cylinder needles, these needles can be brought to the lowered position so as not to interfere with subsequent working steps. Preferably, the transferring apparatus is designed to collect respective stitches of the last course 8' from all the cylinder needles, then couple two by two said stitches and finally position each pair of stitches on the needles belonging to the first or second semicircle.

In addition, the positioning device may comprise a turner 13 configured to operate directly above the machine cylinder 5 and comprising, for example, a pneumatic suction tube which overturns the tubular manufactured article once it has been formed, so as to turn it inside out after being collected from the cylinder needles but before having coupled the opposite stitches together, and to reposition the tubular manufactured article within the lower cylinder, after having coupled the opposite stitches together and before closing the end.

The transferring apparatuses and the turners are known per se but in the present case, in particular, the transferring apparatus is configured to reposition the collected stitches onto the machine needles, whereas the turner is structured to remove the sock from the machine cylinder and to turn it inside out, while remaining above the cylinder itself. Specifically, the transfer apparatus 12 may comprise a supporting element 14 preferably having annular shape and carrying a plurality of transferring members 15 for collecting all the stitches present on the machine needles. Even more preferably, the supporting element 14 carries a plurality of transferring members 15, whose number is equal to the machine needles, each of which is intended to collect the stitch that is on a respective machine needle. The transferring members may be arranged in the same direction as the needles, each above a respective needle as shown in the figures, so that the free end 16 of each of them may contact the upper part of a respective machine needle and collect the stitch located thereon Alternatively, the transferring members may be arranged perpendicular to the needles and may be radially moved with respect to the cylinder in order to collect the stitch from a respective needle.

The supporting element 14 comprises a fixed portion 14' and a movable portion 14", each carrying the same number of transferring members. The fixed portion and the movable portion are combined with each other by means of a joint 17, which allows said movable portion to be moved between an initial position, in which it is aligned and coplanar with the fixed portion, as shown for example in figures 1-7, and a position rotated by 180° with respect to the initial position, so that each transferring member 15 of said movable portion is close to or in contact with a respective transferring member of the fixed portion, as shown in figure 9.

The transferring apparatus also includes means - not shown - for moving the stitches from the cylinder needles to the transferring members, possibly from the transferring members of the movable portion to the transferring members of the fixed portion and from the transferring members to the cylinder needles. The stitch moving means may comprise pusher elements - not shown - housed in the transferring device, in addition to a tube normally housed in the machine cylinder for housing the tubular manufactured article during its formation. The turner 13 is combined with an upper portion of the transferring apparatus 12 and comprises a containing body 18 in which a tubular element 19, having suction means 20 combined therewith, is slidingly mounted. When the positioning device is arranged above the lower cylinder with the transferring members in contact with the needles, the tubular element is moved downward so that a portion thereof is located inside the tubular manufactured article. When suctioning by the suction means, an end portion of the tubular manufactured article is kept close to the tubular element so that, by moving the tubular element upwards, the tubular manufactured article is pulled upwards; since an end thereof, constituted by the last course, is locked on the cylinder needles, the tubular manufactured article is turned inside out and arranged in the containing body, as shown in figures 5-10. Advantageously, by integrating the transferring apparatus and the turner with each other, all the operations required to lead the tubular manufactured article to the suitable condition for closing one of its ends, directly at the cylinder of the machine, can be carried out. On the contrary, a device according to known art which provides two separate elements, of which only the transferring apparatus is designed to work at the machine cylinder while the turner is a separate element combined with the machine in a lateral position away from the cylinder, not only would not allow all the operations required for the correct positioning of the manufactured article to be carried out, but would require the manufactured article to be undesirably moved outside the machine and then back at the cylinder, thus involving additional times and potentially causing breakages.

In order for the positioning device to be arranged in the working position, where it is at the machine cylinder, the machine head 3 and the feeding stations 6 are combined with the machine itself so that they can be shifted between an active position, in which they are near the cylinder and contribute to the formation of the tubular manufactured article, as shown in figures 1 and 12, and an idle position in which they are away from the cylinder, to completely clear the space above the latter, as shown in figures 2 and 3. For this purpose, the head 3 and the feeding stations 6 are carried by movement means 21 preferably of motorized type, which comprise a fixed element 22 and a supporting element 23 susceptible to be moved with respect to the fixed element. Specifically, the supporting element may be rotated upwards or sideways with respect to the active position by an angle suitable to clear a space above the cylinder sufficient to receive the positioning device, without interfering with the head and/or yarn feeding stations. Preferably the angle is at least 45° but more preferably it is about 90°, to completely clear the space above the cylinder.

Once the transfer of the pairs of stitches to a half of the cylinder needles has been completed and the tubular manufactured article has been turned inside out, if necessary, and positioned in the cylinder by the positioning device, the positioning device is returned to its resting position and the movement means return the head and the yarn feeding stations from the idle position to the active position, so that they can contribute to close the end of the tubular manufactured article.

In fact, after pairs of stitches of the last course of the tubular manufactured article have been positioned on a half of the cylinder needles, after the tubular manufactured article has been repositioned in the cylinder 4 and after the head and the yarn feeding stations have been returned to their active position, at least one yarn 7 is again fed to these needles so as to join the stitches by knitting them together directly by this yarn fed to said needles. In order to carry out this operation, the cylinder is rotated in reciprocating motion in order to carry out at least two semi-rotations in opposite directions and the needles are brought to different positions in order to produce the stitches needed to knit together the stitches 8" of the two halves of the last course 8'. This allows the two half-courses of the end of the tubular manufactured article, and in particular of a sock, to be joined directly in the machine and by using the same cylinder needles used to produce the manufactured article, without the need to use specific needles for this operation and without the need to take the manufactured article away from the cylinder to close its end by means of external devices, such as linking or sewing heads. Therefore, the proposed solution allows the circular machine to be greatly simplified and the costs to be significantly reduced, compared to the solutions currently available on the market. In a preferred embodiment, during the step of transferring the stitches on half of the cylinder needles, these needles are kept in the restrained position B, so that said stitches remain above the latch 5" of the respective needle. During a first semi-rotation, the needles are alternately selected so that at least one needle brought to the raised position A, at the feeding station 6 of the yarn 7, is followed by at least one needle brought to the restrained position B, at the feeding station 6 of the yarn 7, and so on. Conversely, in the second semi rotation the needles that in the previous semi-rotation intercepted the yarn in the raised position are brought to the restrained position and the needles that previously intercepted the yarn in the restrained potion are brought to the raised position.

The needles may be controlled with any type of selection 1:1, 2:2, 2:1 and so on, provided that first needle groups G1 alternate with second needle groups G2, wherein said first and second groups comprise at least one needle. Preferably, the selection is of the 1:1 type in which a needle in raised position A is followed by a needle in restrained position B and so on. Thus, each needle in raised position intercepts the main yarn and unloads the pair of stitches it supports, while each needle in restrained position intercepts the main yarn and restrains the two stitches it supports. Since the positions of the needles are reversed in the two semi-rotations, in the next semi-rotation the needles which previously restrained the stitches now unload them, while the others ones restrain the stitch formed in the previous semi-rotation. Preferably at least two pairs, and particularly preferably three pairs, of semi-rotations such as those described above are carried out, without however excluding that an odd number of semi-rotations may be carried out. In order to be able to unload all stitches from the cylinder needles, at least one additional semi-rotation can be carried out in which all needles of the working half of the needles are brought to the raised position.

Therefore, the method according to the invention provides that the end of a tubular manufactured article, and in particular the toe of a sock, is closed directly on the circular machine, without the aid of any linking or sewing device to be combined with the machine. Such closure is achievable by simply positioning pairs of stitches of the last course on a half of the cylinder needles, each pair comprising a stitch initially carried by a needle belonging to one half of the cylinder needles and a stitch initially carried by an opposite needle of the other half of the cylinder needles, with reference to a diameter D of the cylinder, and by joining these stitches by processing at least one yarn with the cylinder needles that carry pairs of stitches. Therefore and advantageously, the end of the manufactured article and specifically the toe if it is a sock, is closed or joined by means of a part of the cylinder needles, which contributed to the formation of the remaining part of the manufactured article. This avoids the need to move away the manufactured article from the machine cylinder during its closing and the need to have specific needles, in addition to those of the machine, to carry out this operation, as well as the need for specific linking or sewing devices external to the machine or in any case combined therewith, but outside the normal working area of the machine. By sewing, stitching or linking the end of the tubular manufactured article directly by means of the same cylinder needles at the end of the production of the manufactured article, the machine, compared to a machine with an external sewing device, can be simplified, thus reducing costs and improving its reliability as it does not have any specific needle, intended for sewing, which, as well as the members supporting the stitches during sewing, is particularly subject to wear due to the rubbing with the needle, when the latter comes into contact with them. According to the method, the sock is produced in traditional manner and remains arranged in the lower cylinder during its formation, as usual. Preferably, the stitches of the needles of the first semicircle SC1 are placed on the needles of the second semicircle SC2 but this does not excludes that pairs of stitches originally supported by opposite cylinder needles are combined with each other and then rotated by a desired angle before each being arranged on a needle of a half of adjacent cylinder needles. During the step of positioning stitches on half of the cylinder needles, the needles of this half of the cylinder needles may be kept in their restrained position. This advantageously allows the stitches to be collected so that they remain above the latch 5” of the needle 5, so as to be able to subsequently choose what type of stitches are to be produced, in order to join the stitches of the last course together.

To carry out the joining of the end of the manufactured article, the cylinder is rotated to perform at least two rotations. Preferably, the cylinder is rotated in reciprocating motion to perform at least two semi-rotations in opposite directions in which, at the yarn feeding station, needles brought to the raised position are alternated with needles kept or brought to the restrained position, so that the needles that intercepted the yarn in the raised position during the first semi-rotation intercept the yarn in the restrained position during the second semi-rotation and, conversely, the needles that intercepted the yarn in the restrained position during the first semi-rotation intercept the yarn in the raised position during the second semi-rotation.

At the end of the step of joining the stitches of its end, the manufactured article is unloaded from the machine as usual, passing through the cylinder, but its end is already closed and not open as normally happens. Therefore, this method allows the manufactured article to be made in the traditional way, starting from an end thereof, i.e. the edge in the case of a sock, which is intended to remain open, and ending with the opposite end which is closed directly by the machine needles, at the end of the production of the manufactured article.

Before the steps of coupling the opposite stitches together and arranging the pairs of stitches on part of the cylinder needles, the tubular manufactured article may be turned inside out and then, after the aforesaid steps, it may be arranged again in the cylinder but remaining inside out.

To allow the positioning device to be arranged above the cylinder during the collecting and positioning steps, the head and the yarn feeding stations are moved to an idle position by being overturned or shifted sideways.

Half of the stitches of the last course are collected by means of the transferring members of the movable portion and the other half are collected, if necessary, by means of the transferring members of the fixed portion. In this case, the stitches are coupled together by overturning the movable portion onto the fixed portion and pushing or pulling the stitches present on the movable portion so that they pass onto the fixed portion.

Finally, the stitches thus coupled are moved from the fixed portion, after the movable portion has been moved away, to half of the cylinder needles by suitable means. In the event that only one half of the stitches are collected, at the end of the collection the movable portion is overturned directly onto the needles of the second half of the cylinder and the stitches it supports are brought onto these needles.

At this point, the head and yarn feeding stations are returned to the active position so as to contribute to close the end of the manufactured article, simply by processing the yarn through half of the cylinder needles on which the stitches are arranged.

The invention is based, therefore, on this concept: collecting at least half of the stitches of the last course of the tubular manufactured article, which are arranged on adjacent needles of the cylinder, then moving these stitches so that on another half of the needles of the cylinder there are pairs of stitches originally arranged on opposite cylinder needles, with reference to its diameter, and joining the stitches by processing a yarn fed to the needles of said other half of the needles, so that the end of the tubular manufactured article is closed directly by the same needles which contributed to the formation of the manufactured article and without the aid of needles or additional sewing or linking devices. Therefore, in order to meet incidental and specific requirements, several variations and modifications could be made by a field technician to the illustrated and described embodiments of present invention, provided that all are included in the protection scope of the invention as defined by the following claims.