WO2001034890A1

WO2001034890A1 - Method and device for transferring a tubular item, particularly a sock, from the machine that produces it to a sewing machine

Info

Publication number: WO2001034890A1
Application number: PCT/EP2000/010935
Authority: WO
Inventors: Gualtiero Gatelli; Cesare Colosio
Original assignee: COLOSIO CESARE Srl; Cesare Colosio SpA
Current assignee: COLOSIO CESARE Srl; Cesare Colosio SpA
Priority date: 1999-11-10
Filing date: 2000-11-06
Publication date: 2001-05-17
Anticipated expiration: 2002-05-10
Also published as: ITMI992348A1; AU1392201A; IT1314218B1; ITMI992348A0

Abstract

A method and a device for transferring a tubular item, particularly a sock, from the machine that manufactures it to a sewing machine which is adapted to close an axial end of the item. The method consists in: producing a tubular item on a circular hosiery knitting machine, starting from one of its axial ends and ending its manufacture at the opposite axial end to be closed; retaining the loops of the last row of knitting formed on the needles of the machine; engaging the axial end to be closed on the item, proximate to the last row of knitting formed, by means of a plurality of grippers (8) which are arranged along a circumference whose diameter is smaller than the diameter of the cylindrical surface along which the needles are arranged; and disengaging the item from the needles of the machine. Then the item, engaged by the grippers, is transferred outside the circular hosiery knitting machine and its axial end to be closed is flattened by moving at least two of the grippers, located in two diametrically opposite regions of the circumference, mutually apart along the diametrical line that connects them and by moving the other grippers toward the diametrical line. Finally, the axial end to be closed of the item, flattened in this way, is inserted between the two feed guides of a sewing machine.

Description

METHOD AND DEVICE FOR TRANSFERRING A TUBULAR ITEM, PARTICULARLY A SOCK, FROM THE MACHINE THAT PRODUCES IT TO A SEWING MACHINE

Technical field

The present invention relates to a method and a device for transferring a tubular item, particularly a sock or a stocking, from the machine that produces it to a sewing machine which is adapted to close an axial end of the item.

Background Art

It is known that in the conventional manufacturing method, socks are unloaded from the machine that produces them while their toe is still open and are then subjected to a toe closure operation on appropriately provided darning or sewing machines.

The socks are loaded onto the looping or sewing machines manually, flattening the toe so as to arrange face to face the two flaps to be sewn or looped, and this requires particular skill on the part of the operator. This loading operation significantly affects the overall manufacturing costs of the socks.

For this reason, the need has long been felt to eliminate this manual operation from the sock manufacturing cycle.

In order to meet this need, circular sock knitting machines have been devised which, by following particular knitting cycles with the aid of additional devices, are capable of manufacturing socks in which the toe is already closed.

The particular knitting cycles devised on these machines, however, are generally slower than the conventional manufacturing cycles and therefore, owing to the production loss, the advantage offered by these machines in eliminating the need for sewing or looping machines is rather modest in terms of overall manufacturing costs.

Devices have also been designed which are capable of transferring, loop by loop, the last formed row of knitting, which constitutes the toe of the sock, from the needles of the circular hosiery knitting machine to a supporting element which can arrange the loops of one half of said row adjacent to the loops of the other half, in order to then subject them to the action of a sewing or looping head which is fitted on the same machine that manufactures the sock or laterally thereto.

This method, too, significantly slows the sock manufacturing cycle owing to the time required to perform the transfer, loop by loop, of the row of knitting that constitutes the toe of the sock, and therefore achieves a limited advantage with respect to the conventional method.

In order to provide a faster transfer of the sock from the machine that manufactures it to the sewing machine that closes the toe of the sock, it has been proposed to remove the sock from the machine that manufactures it by clamping or otherwise engaging the toe, which is the last part of the sock to be formed, in two diametrically opposite regions and to move said two regions mutually apart so as to flatten the toe, which can thus be inserted mechanically between the feed guides of a sewing machine.

This method achieves the advantage of not slowing significantly the manufacturing cycle of the circular hosiery knitting machine, but it has the drawback that it produces a finished product which is not always fully satisfactory as regards precision in forming the toe seam.

Flattening of the toe of the sock produced by holding the toe in two diametrically opposite regions in fact arranges the two flaps of the toe, which lie between these two regions, along an arc, whereas in order to obtain a fully satisfactory seam the two flaps of the toe must be side by side and arranged in a straight line. Disclosure of the Invention

The aim of the present invention is to solve the above problems by providing a method and a device which allow to automatically transfer a sock or stocking, or more generally a tubular item, from the machine that manufactures it to a sewing machine which is adapted to close the toe of the sock, or more generally an axial end of the item, obtaining a fully satisfactory finished product.

An object of the invention is to provide a method and a device which do not hinder excessively the productivity of the machine that manufactures the item.

Another object of the invention is to provide a device which is compatible with currently commercially available sewing machines.

Another object of the invention is to provide a device which is highly reliable and precise in operation.

This aim, these objects and others which will become better apparent hereinafter are achieved by a method for transferring a tubular item, particularly a sock, from the machine that manufactures it to a sewing machine which is adapted to close an axial end of the item, characterized in that it comprises:

producing a tubular item on a circular hosiery knitting machine, starting from one of its axial ends and ending its manufacture at the opposite axial end to be closed;

retaining the loops of the last row of knitting formed on the needles of the machine;

engaging the axial end to be closed of the item, proximate to the last row of knitting formed, by means of a plurality of grippers which are arranged along a circumference whose diameter is smaller than the diameter of the cylindrical surface along which the needles are arranged;

disengaging the item from the needles of the machine;

transferring the item, engaged by the grippers, outside the circular hosiery knitting machine;

flattening the axial end to be closed of the item, which is engaged by the grippers, by moving at least two of the grippers, located in two diametrically opposite regions of the circumference, mutually apart along the diametrical line that connects them and by moving the other grippers toward the diametrical line, thus arranging the two flaps of the axial end to be closed of the item so that they face each other;

inserting the axial end to be closed of the item, flattened in this way, between the two feed guides of a sewing machine.

In order to perform the method according to the invention, a device is preferably used which is characterized in that it comprises a transfer unit provided with a plurality of grippers which can move on command from a pick-up position, in which they are arranged along a circumference whose diameter is smaller than the diameter of the surface along which the needles of a circular hosiery knitting machine that produces the tubular item are arranged, to a flattening position, in which at least two of the grippers, located in two diametrically opposite regions, are moved mutually apart along the diametrical line that connects them, while the other grippers are moved toward the diametrical line with respect to the pick-up position, and vice versa; the transfer unit being movable on command from a first position, in which it is arranged so that the grippers are in the pick-up position and coaxially face the upper end of the needle cylinder of the hosiery knitting machine in order to engage the axial tip of the item retained by the needles, to a second position, in which it is arranged in a standby station laterally to the hosiery knitting machine, so that the axial tip of the item is engaged by the grippers in the flattening position; a feeder means being provided which can be actuated on command in order to transfer the item from the standby station to a sewing machine, inserting the axial tip of the item, flattened by the grippers, between two mutually facing feed guides of the sewing machine.

Brief description of the drawings

Further characteristics and advantages of the invention will become better apparent from the following detailed description of a preferred but not exclusive embodiment of the method according to the invention and of the device for performing it, illustrated only by way of non-limitative example in the accompanying drawings, wherein:

Figures 1 and 2 are front sectional views, taken along a vertical plane, of the part of the device according to the invention that relates to the transfer unit, installed on a circular hosiery knitting machine, during the initial steps of operation;

Figure 3 is an enlarged-scale view of a detail of Figure 2;

Figure 4 is a view of the same detail of Figure 3 in a subsequent step of operation;

Figure 5 is a view of the same part of the device shown in the preceding figures, in another step of operation;

Figure 6 is a top plan view of the device in the position that corresponds to Figure 5 and with the transfer unit shown in cross-section along the plane VI-VI indicated in Figure 5;

Figure 7 is a view of the device, similar to Figure 6 but with the transfer unit in the standby station;

Figure 8 is a partially sectional side view, taken along a vertical plane, of the device in the position shown in Figure 7;

Figure 9 is a front sectional view, taken along a vertical plane, of the device in the position shown in Figures 7 and 8;

Figure 10 is a view of the device, similar to Figure 8 but in a subsequent step of operation;

Figure 11 is a view of the device, similar to Figure 10 but in another step of operation;

Figure 12 is a sectional view of Figure 11 , taken along the plane XII-XII, with some details omitted for the sake of simplicity;

Figure 13 is a view of the device, similar to Figure 11 but in a further step of operation which illustrates the insertion of the axial end to be closed of the item between the feed guides of a sewing machine;

Figure 14 is an enlarged-scale sectional view of a detail of Figure 13, taken along the plane XIV-XIV;

Figure 15 is an enlarged-scale sectional view of a detail of Figure 9, taken along the plane XV-XV;

Figure 16 is an enlarged-scale sectional view of a detail of Figure 12, taken along the plane XVI-XVI, but with the item omitted.

Ways of carrying out the invention

The device for performing the method according to the invention is described hereinafter in its preferred application to a single-cylinder circular hosiery knitting machine for transferring a sock from the circular machine to a sewing machine which is adapted to close the toe of the sock; nonetheless, the device can in any case be used, more generally, to transfer a tubular item from the circular hosiery knitting machine that manufactures it to a sewing machine suitable to close the item at one of its axial ends.

The device according to the invention, generally designated by the reference numeral 1 , includes a transfer unit 2 which is meant to be installed directly on the supporting structure 3 of a circular hosiery knitting machine 4 or on an independent supporting structure which is located in the vicinity of the machine 4.

The circular hosiery knitting machine 4 includes, in a per se known manner, a needle cylinder 5 which has a vertical axis 5a and accommodates, on its curved surface, a plurality of needles 6 which can be actuated in order to produce a sock 7 or tubular item in general. The needle cylinder 5, during the manufacture of the sock 7, is rotationally actuated about its own axis 5a.

The machine 4 can be provided, above the needle cylinder 5, with a dial which is not shown for the sake of simplicity and can be moved vertically in a per se known manner.

The transfer unit 2 is provided with a plurality of grippers 8 which can move on command from a pick-up position, in which they are arranged along a circumference 9 whose diameter is smaller than the diameter of the cylindrical surface along which the needles 6 are arranged, to a flattening position, in which at least two of the grippers 8, located in two diametrically opposite regions, are moved mutually apart along the diametrical line 9a that connects them, while the other grippers are moved toward the diametrical line 9a with respect to the pick-up position, and vice versa.

The transfer unit 2 can move on command from a first position, in which it is arranged so that the grippers 8 are in the pick-up position and coaxially face the upper end of the needle cylinder 5 in order to engage the tip, i.e., the toe 7a, of the sock 7, to a second position, in which the transfer unit is arranged in a standby station 10 laterally to the machine 4, with the toe 7a engaged by the grippers 8, in the flattening position.

The device comprises a feeder means 11 which can be actuated on command in order to transfer the sock 7 from the standby station 10 to a sewing machine of a known type, not shown for the sake of simplicity, inserting the toe 7a of the sock 7, flattened by the grippers 8, between a pair of feed guides 12a, 12b of the sewing machine which are arranged side by side on a horizontal plane.

More particularly, the transfer unit 2 includes an arm 13 which lies substantially horizontally and is fixed, at one of its ends, to the upper end of a shaft 14 which has a vertical axis 14a which is spaced laterally with respect to the needle cylinder 5.

The shaft 14 is inserted coaxially, and so that it can slide axially and can rotate about its own axis 14a, inside a guiding sleeve 15 which is fixed to the supporting structure 3.

The lower end of the shaft 14 is connected to a bush 16 which is coaxial thereto and can rotate freely about its own axis but is prevented from performing any axial translatory motion with respect to the shaft 14. A female thread is formed coaxially in the bush 16 and engages a threaded shaft 11 which is connected to the output shaft of an electric motor 18.

A cylindrical gear 19 is keyed around an intermediate region of the shaft 14 and meshes with a worm screw 20 which is connected to the output shaft of another electric motor, not shown for the sake of simplicity, which is supported by the supporting structure 3.

The axis of the worm screw 20 is inclined with respect to the horizontal by an angle equal to the angle of its helix, so that a vertical sliding of the gear 19 with the shaft 14 produces no rotation of said shaft 14 and therefore of the arm 13 about the axis 14a. In practice, by actuating the motor 18, the shaft 14, and therefore the arm 13, are raised or lowered, whereas by actuating the worm screw 20 the shaft 14, and therefore the arm 13, are turned about the axis 14a through a preset angle in order to move the transfer unit 2 from the first position to the second position or vice versa.

Clearly, the lifting and lowering of the arm 13, as well as its rotation about the axis 14a, may be achieved by virtue of other conventional actuation means.

An annular body 21 is fixed to the end of the arm 13 that lies opposite the end that is connected to the shaft 14; the body has a vertical axis 21 a and supports the grippers 8.

The grippers 8 are constituted by a plurality of rods which are arranged on a substantially horizontal plane and have, at their end directed toward the axis 21 a, a point 22 which is directed downward and is meant to engage the sock 7.

When the grippers 8 are in the pick-up position, the points 22 are arranged along the circumference 9, while when the grippers 8 are in the flattening position, the points are aligned along the diametrical line 9a that connects two of these points 22 which are constituted, in the illustrated case, by the points of the two rods designated by the reference numeral 8a.

The rods 8a are slidingly accommodated inside two radial slots which are formed in the lower face of the body 21 and are mutually aligned along a diametrical line of the lower face of the body 21. The other rods, designated by the reference numerals 8b, are slidingly accommodated inside slots which are likewise formed in the lower face of the body 21 but are orientated at right angles to the diametrical line 9a along which the slots that accommodate the rods 8a are aligned.

The transfer of the points 22 of the rods 8a, 8b from the pick-up position to the flattening position is provided by virtue of an actuation means which includes an annular member 23 which coaxially faces the body 21 in a downward region. The annular member 23 is supported, so that it can rotate about its own axis, by the body 21 and is peripherally provided with a toothed ring 34 with which there meshes a pinion 25 which is connected to the output shaft of an electric motor 26 which is fitted on the body 21.

The annular member 23 has, on its face directed toward the body 21 , for each rod 8a and 8b, a cam-like path 27a, 27b which can be engaged by a heel 28 which extends from an intermediate region of the rods 8a, 8b and protrudes downward from the slot of the body 21 that accommodates the corresponding rod. The cam-like paths 27a, 27b have a radial component with respect to the axis 21a, so that turning the annular member 23 by virtue of the actuation of the motor 26 produces the translatory motion of the rods 8a, 8b along the slots of the body 21 in which they are accommodated.

Conveniently, in the upper end of the needle cylinder 5, along a circumference which is coaxial to the cylindrical surface along which the needles are arranged and is equal in diameter to the circumference along which the points 22 of the rods 8a, 8b are arranged in the pick-up position, there are recesses 29 which are suitable to partially accommodate the points 22.

The arm 13 is provided with a presser 30 which, when the body 21 of the transfer unit 2 is arranged above the needle cylinder 5 and coaxially thereto, can engage the head of the needles 6 in order to produce the lowering of the needles 6, thus disengaging them from the sock 7.

The presser 30 is provided as a hollow cylindrical piston of a pneumatic cylinder 31 which is connected in an upward region and coaxially with respect to the body 21.

The lower end of the presser 30 has, at the rods 8a and 8b, suitable recesses so as to be able to move beyond, in a downward region, the rods with its lower end and so as to be able to lower the heads of the needles 6 below the knitting plane of the beating sinkers of the machine in order to fully disengage the toe 7a of the sock 7 from the needles 6.

Advantageously, the device according to the invention also comprises a means 32 for overturning the sock 7 engaged by the grippers 8.

The overturning means 32 is conveniently constituted by a suction tube 33 which can be connected to a suction means of a known type, not shown for the sake of simplicity; the inlet of the tube faces from above and internally the circumference along which the points 22 of the rods 8a, 8b are arranged in the pick-up position.

The suction tube 33 is supported by a platform 34 which is in turn supported, so that it can slide vertically by means of adapted guides 35, by the arm 13. A pneumatic cylinder 36 having a vertical axis is fitted on the arm 13, is connected by means of the stem of its piston to the platform 34 and can be actuated so as to raise or lower the inlet of the suction tube 33 with respect to the grippers 8.

The feeder means 1 1 comprises a caliper 37 which can engage the regions of the toe 7a of the sock 7 that lie between the points 22 of the rods 8a, 8b in the flattening position in the standby station 10.

The caliper 37 includes a caliper body 38 to which two rows of jaws 39a, 39b are hinged about two mutually parallel axes; the jaws face each other and can engage the sock 7 by virtue of grip regions located at their ends that lie opposite the end that is hinged to the body 38.

The jaws 39a, 39b are mutually spaced so as to not interfere with the points 22 of the rods 8a, 8b when the sock 7 is gripped by the caliper 37.

The mutually facing jaws 39a, 39b are pushed against each other by springs 40. An actuation shaft 41 is interposed between the mutually facing faces of the jaws 39a, 39b and lies parallel to the axes about which the jaws 39a, 39b are pivoted to the body 38, with conical portions 42 which couple to correspondingly shaped regions of the jaws 39a, 39b so that a translatory motion of the actuation shaft 41 produces a spacing of the grip regions of the jaws 39a, 39b in contrast with the action of the springs 40 or allows the springs 40 to move mutually closer the grip regions of the jaws 39a, 39b.

The translatory motion of the actuation shaft 41 can be provided by means of pneumatic actuators, mechanical actuators or other conventional actuators, mounted on the body 38 of the caliper 37 or arranged proximate to the standby station 10 and the feed guides 12a, 12b of the sewing machine.

The caliper 37 can move on command from a position for receiving the sock 7, in which it is arranged so that the grip regions of its jaws 39a, 39b are directed upward in order to grip the toe 7a of the sock 7, which is engaged with the points 22 of the rods 8a, 8b in the flattening position and is directed downward, to a release position, in which it is arranged so that the grip regions of the jaws 39a, 39b are directed downward.

The body 38 of the caliper 37 is mounted on a support 43 which can perform a translatory motion along a direction which is parallel to the mutual mating plane of its jaws and is aligned with the passage for the toe 7a of the sock 7 formed between the feed guides 12a, 12b of the sewing machine.

The support 43 is fixed to a conveyor chain which lies between the standby station 10 and the feed guides 12a and 12b.

More specifically, the support 43 is constituted by two chains 44a, 44b which are arranged side by side; each chain meshes with two pinions 45a, 45b which can be actuated in order to move the chains and therefore the caliper 37.

It should be noted that the caliper 37, in passing from the standby station 10 to the feed guides 12a, 12b of the sewing machine, passes from the upper portion to the lower portion of the chains 44a, 44b that move it and therefore overturns the sock 7, which is inserted between the feed guides 12a, 12b so that its toe 7a is directed upward.

A first tensioner 46 is fitted at the standby station 10, on the same supporting structure 3 or on an independent supporting structure, and can engage, when the caliper 37 is in the pick-up position, a portion of the sock 7 which lies above its toe 7a engaged by the point 22 of the rods 8a, 8b in order to tension the sock 7 in an upward direction. The tensioner 46 is arranged so as to engage the pocket 7b of the toe 7a of the sock 7.

The tensioner 46 is preferably constituted by a pneumatic cylinder 47 which can be actuated so as to engage, by virtue of the stem of its piston, the pocket 7b of the toe 7a of the sock 7.

Proximate to the feed guides 12a, 12b of the sewing machine, at a lower vertical elevation than the feed guides 12a, 12b, there is a second tensioner 48 which can engage a portion of the sock 7 that is located below the toe 7a, engaged with the caliper 37, before its insertion between the feed guides 12a, 12b in order to tension the sock 7 in a downward direction.

The second tensioner 48 is constituted by an oscillating arm 49 which is actuated by means of a pneumatic cylinder 50 and can again engage the pocket 7b of the toe 7a of the sock 7. The second tensioner 48 is mounted on a carriage, not shown for the sake of simplicity, which can move horizontally on command, together with the caliper 37, parallel to the passage formed between the feed guides 12a and 12b in order to engage the sock 7 before its insertion between the feed guides 12a, 12b and disengage from it after its insertion between the feed guides 12a, 12b.

The operation of the device in performing the method according to the invention is as follows. The sock is manufactured, in a per se known manner, on the circular hosiery knitting machine 4 starting from the top, i.e., from the end that lies opposite the toe 7a, and is completed by forming the toe 7a. A pocket 7b, meant to receive the toes of the user, is formed in a per se known manner proximate to the toe 7a.

The toe 7a can be completed, in a per se known manner, by means of a border which is thicker than the remaining part of the sock and is meant to be removed by the sewing machine that closes it. Said thicker border is preferably constituted by a tubular border also known as double selvage.

It should be noted that before forming the thicker border it is possible to form, in a per se known manner, a few rows of knitting with a yarn which is elastic and/or has a smaller diameter than the yarns used to form the regions directly before and after these rows. These rows may be removed by the sewing machine and form a region which, by virtue of the longitudinal tensioning of the sock, becomes narrower and elongates and is the region of the sock that is meant to be arranged between the feed guides 12a, 12b of the sewing machine.

When forming of the toe 7a is complete, the needles 6, which have formed the last row of knitting, are raised so that the loops of the last row of knitting pass on the stem of the corresponding needle below the tongue of the needle. In this condition, the toe 7a of the sock is engaged with the needles 6 and the remaining part of the sock 7 descends, in a per se known manner, into the needle cylinder 5.

The rotation of the needle cylinder 5 is stopped in a very specific angular position, and the dial, if present, is raised above the needle cylinder 5 so as to free, above the needle cylinder 5, a region into which the transfer unit 2 can be inserted.

At this point, the arm 13, in the raised position, with the inlet of the suction duct 33 and the presser 30 likewise in the raised position, is turned about the axis 14a by actuating the worm screw 20, so as to arrange the annular body 21 above and coaxially to the needle cylinder 5 (Figure 1).

The points 22 of the rods 8a, 8b are in the pick-up position, i.e., are arranged along a circumference 9 which is centered on the axis 21 a, which coincides, in this condition, with the axis 5a of the needle cylinder 5, and has a smaller diameter than the cylindrical surface along which the needles 6 are arranged.

By virtue of the actuation of the electric motor 18, the arm 13 is lowered, causing the insertion of the points 22 in the toe 7a of the sock 7 proximate to the needles 6. The insertion of the points 22 in the toe 7a of the sock is allowed by the presence of the recesses 29, which partially receive the points 22. At this point the pneumatic cylinder 36 is actuated, lowering the inlet of the suction tube 33, which is arranged above and inside the circumference along which the points 22 of the rods 8a, 8b are arranged in the pick- up position (Figure 2).

The presser 30 is then lowered toward the upper end of the needle cylinder 5 so as to lower the needles 6, which by retracting into the needle cylinder 5 release the loops of the last formed row of knitting, leaving the sock engaged exclusively with the points 22 of the rods 8a, 8b (Figure 3).

At this point, the suction duct 33 is connected to the suction means, drawing into it the sock 7, which is thus overturned above the toe 7a engaged by the points 22 of the rods 8a, 8b (Figure 4).

The presser 30 and the inlet of the suction tube 33 are then raised and the arm 13 too is raised by virtue of the actuation of the electric motor 18 (Figure 5).

At this point, the worm screw 20 is actuated, causing the rotation of the arm 13 about the axis 14a and transferring the annular body 21 from the position in which it is coaxial to the needle cylinder 5 to the standby station 10 arranged laterally to the needle cylinder 5 (Figures 6 and 7).

It should be noted that by virtue of a control of the rotation of the needle cylinder 5, which can be provided by virtue of devices which are already extensively used in the field of circular hosiery knitting machines, the rotation of the needle cylinder 5 about its own axis 5a, at the end of the formation of the sock 7, has been stopped so that the lateral ends of the toe 7a to be closed by stitching lie at the points 22 of the rods 8a.

During or directly after the transfer of the annular body 21 from the position in which it is coaxial to the needle cylinder 5 of the machine 4 to the standby station 10, the motor 26 is activated and, by causing the rotation of the annular body 23 about the axis 21 a, causes the mutual spacing of the points 22 of the rods 8a along the diametrical line 9a and simultaneously causes the movement of the points 22 of the rods 8b toward the diametrical line 9a until they lie substantially at the diametrical line 9a (Figure 7).

This movement of the rods 8a, 8b causes a flattening of the toe 7a of the sock 7 and therefore a mutual approach of the two flaps of the toe 7a to be stitched.

It should be noted that owing to the fact that flattening is performed not only by retaining the lateral ends of the toe 7a but also by guiding regions of the toe 7a that lie between these lateral regions, the two mutually facing flaps of the toe 7a are arranged along a substantially straight path between the two lateral ends and therefore in an optimum condition for producing precise stitching of the toe 7a.

In the standby station 10, the toe 7a, engaged by the points 22 of the rods 8a, 8b in the flattening position, is directed downward and faces the caliper 37 while the sock 7 is still being drawn into the suction tube 33 above the toe 7a (Figures 8 and 9).

At this point, by virtue of the actuation of the motor 18, the arm 13 is lowered, placing the points 22 of the rods 8a, 8b between the jaws 39a, 39b of the caliper 37 in the open position.

The tensioner 46 is then actuated so as to engage the pocket 7b of the toe 7a of the sock 7, tensioning the sock 7 in an upward direction (Figure 10).

The tensioning provided by the tensioner 46 has the dual effect of preventing portions of the pocket 7b of the toe 7a from protruding below the region of the toe 7a that is engaged by the points 22 of the rods 8a and 8b and from being engaged by the caliper 37, and of correctly positioning the region of the toe 7a of the sock engaged by the points 22 of the rods 8a, 8b with respect to the mutually facing jaws 39a, 39b of the caliper 37.

At this point, the actuation shaft 41 is actuated along its own axis, causing the closure of the caliper 37, which engages, by virtue of the grip regions of its mutually facing jaws 39a, 39b, the regions of the toe 7a that lie between the points 22 of the rods 8a, 8b (Figure 11).

The motor 26 is then actuated so as to rotate in the opposite direction with respect to the previous one, so as to produce the rotation of the annular body 23 through a preset angle in order to slightly space from the diametrical line 9a the point of the rods 8b, while the rods 8a maintain their position due to the different configuration of the paths 27b with respect to the paths 27a. This partial spacing of the points of the rods 8b with respect to the diametrical line 9a facilitates extraction of the points of the rods 8b from the sock.

The arm 13 is then raised by actuating the motor 18 so as to extract the points 22 of the rods 8a, 8b from the toe 7a of the sock 7, which thus remains rigidly coupled only to the caliper 37 (Figure 12).

Once the points of the rods 8a, 8b have moved beyond and above the jaws 39a, 39b of the caliper 37, the rotation of the annular body 23 about a preset angle is completed so as to reposition the points 22 of the rods 8a, 8b along the circumference 9.

By actuating the chains 44a, 44b, the caliper 37 is moved from the standby station 10 to the feed guides 12a, 12b of the sewing machine. During this transfer, the caliper 37 passes from the upper portion of the chains 44a, 44b to the lower portion, overturning the sock 7 which, upon entry between the feed guides 12a, 12b, is arranged so that the toe 7a engaged by the caliper 37 is directed upward.

Again by virtue of the movement of the caliper 37 provided by the chains 44a, 44b, the toe 7a of the sock is inserted along the passage formed between the feed guides 12a, 12b which face each other on a horizontal plane. Upon insertion, the caliper 37, which is engaged with the thicker border of the toe 7a of the sock 7, lies directly above the feed guides 12a, 12b (Figure 13).

Before inserting the sock 7 between the feed guides 12a, 12b, the second tensioner 48 is activated and also engages the pocket 7b of the toe 7a, tensioning the sock 7 downward. This tensioning elongates the rows of knitting adjacent to the thicker border and narrows the sock at these rows, facilitating the insertion of the socking between the feed guides 12a, 12b and arranging it correctly for the subsequent stitching operation. The second tensioner 48 remains engaged with the sock 7, moving together with the caliper 37 until the sock has been inserted between the feed guides 12a, 12b of the sewing machine.

The sock 7 is then conveyed along the feed guides 12a, 12b by virtue of the advancement devices fitted to the feed guides 12a, 12b of conventional sewing machines and is subjected to stitching, with removal of the thicker border, at the toe 7a.

It should be noted that directly after the removal of the sock 7 from the circular hosiery knitting machine 4 the machine 4 can begin to knit a new sock, and therefore its production cycle is slowed, albeit minimally, by the transfer of the sock 7 from the machine 4 to the sewing machine. In practice it has been observed that the device and the method according to the invention fully achieve the intended aim and objects, since they allow to automatically transfer a sock, or more generally a tubular item, from the circular hosiery knitting machine that manufactures it to a sewing machine which is adapted to close the toe of the sock or more generally an axial end of the item without significantly penalizing the production cycle of the item, achieving a fully satisfactory result in stitching.

The method and the device thus conceived are susceptible of numerous modifications and variations, within the scope of the appended claims. All the details may be replaced with other technically equivalent elements.

In practice, the materials used, as well as the dimensions, may be any according to requirements and to the state of the art.

Claims

1. A method for transferring a tubular item, particularly a sock or stocking, from the machine that manufactures it to a sewing machine adapted to close an axial end of the item, characterized in that it comprises:

disengaging the item from the needles of the machine;

transferring the item, engaged by said grippers, outside the circular hosiery knitting machine;

flattening the axial end to be closed of the item, which is engaged by said grippers, by moving at least two of said grippers, located in two diametrically opposite regions of said circumference, mutually apart along the diametrical line that connects them and by moving the other grippers toward said diametrical line, thus arranging the two flaps of the axial end to be closed of the item so that they face each other;

2. The method according to claim 1 , characterized in that before flattening the axial end to be closed of the item, which is engaged with said grippers, the item is overturned above its axial end to be closed, which is engaged with said grippers.

3. The method according to claims 1 and 2, characterized in that the insertion of the item between the pair of feed guides of the sewing machine is performed by removing the item from the grippers by virtue of a feeder means and by overturning said item in order to direct upward its axial end to be closed, which was previously engaged by said grippers, before its insertion between said feed guides.

4. The method according to one or more of the preceding claims, wherein said item is constituted by a sock and its axial end to be closed is constituted by the toe of the sock, characterized in that said at least two of said grippers are engaged with the two opposite lateral regions of the toe to be closed.

5. The method according to one or more of the preceding claims, characterized in that before the transfer of the item from said grippers to said feeder means the pocket of the toe of the sock, arranged above the axial end to be closed which is engaged with said grippers, is tensioned upward.

6. The method according to one or more of the preceding claims, characterized in that before the insertion of the axial end to be closed of the item between the pair of feed guides of the sewing machine, the item is tensioned downward.

7. The method according to one or more of the preceding claims, characterized in that said end to be closed is completed, on the circular knitting machine, by means of a border which is thicker than the remaining part of the sock.

8. The method according to one or more of the preceding claims, characterized in that said thicker border is constituted by a tubular border or double selvage.

9. The method according to one or more of the preceding claims, characterized in that some rows of knitting directly before said thicker border are formed with a yarn which is elastic and/or smaller in diameter than the yarns used to knit the directly contiguous regions of the sock.

10. The method according to one or more of the preceding claims, characterized in that after the formation of the last row of knitting, the needles are raised until the last loop of knitting formed is below the tongue of each needle and the needle cylinder of the machine is stopped.

11. The method according to one or more of the preceding claims, characterized in that after forming the last row of knitting, the needle cylinder of the machine is stopped in a preset angular position about its own axis.

12. A device for transferring a tubular item, particularly a sock, from the machine that manufactures it to a sewing machine which is adapted to close an axial end of the item, characterized in that it comprises a transfer unit provided with a plurality of grippers which can move on command from a pick-up position, in which they are arranged along a circumference whose diameter is smaller than the diameter of the surface along which the needles of a circular hosiery knitting machine that produces the tubular item are arranged, to a flattening position, in which at least two of said grippers, located in two diametrically opposite regions, are moved mutually apart along the diametrical line that connects them, while the other grippers are moved toward said diametrical line with respect to said pick-up position, and vice versa; said transfer unit being movable on command from a first position, in which it is arranged so that said grippers are in said pick-up position and coaxially face the upper end of the needle cylinder of the hosiery knitting machine in order to engage the axial tip of the item retained by said needles, to a second position, in which it is arranged in a standby station laterally to the hosiery knitting machine, so that said axial tip of the item is engaged by said grippers in said flattening position; a feeder means being provided which can be actuated on command in order to transfer the item from said standby station to a sewing machine, inserting the axial tip of the item, flattened by said grippers, between two mutually facing feed guides of the sewing machine.

13. The device according to claim 12, characterized in that it comprises a means for overturning the item engaged by said grippers.

14. The device according to claims 12 and 13, characterized in that said overturning means comprises a suction tube which can be connected to a suction means which is mounted on said transfer unit and faces from above and internally, with its inlet, the circumference along which said grippers are arranged in said pick-up position.

15. The device according to one or more of the preceding claims, characterized in that said suction tube can move on command along a substantially vertical direction in order to lift or lower its inlet with respect to said grippers.

16. The device according to one or more of the preceding claims, characterized in that said transfer unit comprises an arm which supports said grippers and is pivoted to a supporting structure about a vertical rotation axis which is parallel to the axis of the needle cylinder of the hosiery knitting machine and is spaced laterally with respect to the needle cylinder; said arm being able to rotate on command about said rotation axis for the transfer of the transfer unit from said first position to said second position or vice versa.

17. The device according to one or more of the preceding claims, characterized in that said arm can move on command along said rotation axis in order to lift or lower said transfer unit.

18. The device according to one or more of the preceding claims, characterized in that said grippers are constituted by a plurality of rods which are arranged on a substantially horizontal plane and are provided, at one of their ends, with points which are directed downward; an actuation means being provided which acts on said rods for their transfer from said pick-up position, in which they are arranged so that their points lie along said circumference, to said flattening position, in which the points of two rods located in two mutually diametrically opposite regions are moved mutually apart along the diametrical line that connects them, with respect to said pick-up position, while the points of the other rods are arranged substantially at said diametrical line, and vice versa.

19. The device according to one or more of the preceding claims, characterized in that at least two of said rods, located with their point in two diametrically opposite regions of said circumference when said grippers are in the pick-up position, are slidingly supported by said arm along said diametrical line, and in that the other rods are slidingly supported by said arm along directions which are substantially perpendicular to said diametrical line.

20. The device according to one or more of the preceding claims, characterized in that said actuation means comprises an annular member which faces the plane of arrangement of said rods coaxially to said circumference and has, for each one of said rods, at least one cam-like path which can be engaged by at least one transverse heel of said rods, said cam-like path extending with a radial component with respect to the axis of said annular member, which can rotate on command about its own axis with respect to said arm for a translatory motion of said at least two rods along said diametrical line and for a translatory motion of the other rods along directions which are perpendicular to said diametrical line.

21. The device according to one or more of the preceding claims, characterized in that recesses suitable to partially accommodate the points of said rods are provided in the upper end of the needle cylinder of the hosiery knitting machine, along a circumference which is coaxial to the cylindrical surface along which the needles are arranged and is equal in diameter to the circumference along which the points of said rods are arranged in the pick-up position.

22. The device according to one or more of the preceding claims, characterized in that said arm is provided with at least one presser which can engage, when said transfer unit is in said first position, the head of the needles of the circular hosiery knitting machine in order to lower, when the needle cylinder is not moving, said needles into the needle cylinder, producing the release of the item by the needles.

23. The device according to one or more of the preceding claims, characterized in that said feeder means comprises a caliper which can engage the regions of the axial tip of the item that lie between the points of said rods in said flattening position in the standby station.

24. The device according to one or more of the preceding claims, characterized in that said caliper can move on command from a position for receiving the item, in which it is arranged so that the grip regions of its mutually facing jaws are directed upward so as to grip the axial tip of the item, which is engaged with the points of said rods in the flattening position and is directed downward, to a release position, in which it is arranged so that the grip regions of its two mutually facing jaws are directed downward.

25. The device according to one or more of the preceding claims, characterized in that said caliper is mounted on a support which moves parallel to the plane on which its jaws mate and is aligned with the passage formed between the pair of feed guides of the sewing machine which face each other on a substantially horizontal plane.

26. The device according to one or more of the preceding claims, characterized in that in said standby station there is a first tensioner which, when said caliper is in the receiving position, can engage a portion of the item that lies above its axial end engaged by said points of the rods in order to tension the item upward.

27. The device according to one or more of the preceding claims, characterized in that it comprises a second tensioner which is arranged proximate to said feed guides of the sewing machine and is arranged at a lower elevation than said guides; said second tensioner being movable together with said caliper parallel to said passage formed between said feed guides and being engageable with a portion of the item that is located below said caliper in order to tension the item downward, assisting said caliper in the insertion of the item between said feed guides of the sewing machine.

28. The device according to one or more of the preceding claims, wherein said item is constituted by a sock, characterized in that said portion of the item that can be engaged by said first tensioners and said second tensioners is constituted by the pocket of the toe of the sock.

29. The method and device for transferring a tubular item, particularly a sock, from the machine that manufactures it to a sewing machine which is adapted to close an axial end of the item, characterized in that they comprise one or more of the described and/or illustrated characteristics.