Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
A SEWING OR GRAFTING STATION AND A METHOD FOR AUTOMATED CLOSING OF TUBULAR ITEMS AT AN AXIAL END THEREOF
Document Type and Number:
WIPO Patent Application WO/2020/065465
Kind Code:
A1
Abstract:
The present invention concerns a tubular knitted item (1), an apparatus for manufacturing a tubular knitted item (1) comprising a circular knitting machine (2) and a sewing or grafting station (5), and a method for automated closing of tubular knitted items at an axial end thereof, whereby said method comprises the steps of: manufacturing a tubular knitted item (1) having an edge (100) delimiting an open axial end; wherein, once finished, the tubular knitted item (1) has a back and a front and defines a median plane (P) basically orthogonal to the back and to the front; arranging the edge (100) on a circumference having a central axis (K-K); wherein the tubular knitted item (1) with the edge (100) arranged on the circumference has a bulge (18) partially developing around the central axis (K-K); overturning said bulge (18) and associate a first ring-shaped half of the edge (100) to a second ring-shaped half of the edge (100) so that said bulge (18) defines a toe of the tubular knitted item (1); sewing the two halves of the edge (100) to one another so as to make a seam (16) and close the axial end, whereby the overturning takes place around an overturning axis (Y-Y) which is skew with respect to directions orthogonal to the median plane (P).

Inventors:
LONATI ANDREA (IT)
ALGHISI MAURO (IT)
CRISTINI PAOLO (IT)
Application Number:
IB2019/057934
Publication Date:
April 02, 2020
Filing Date:
September 19, 2019
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
SANTONI & C SPA (IT)
International Classes:
D05B23/00; D04B9/40; D04B9/56; D04B15/02
Domestic Patent References:
WO2014131794A12014-09-04
WO2014111206A12014-07-24
Foreign References:
US8893529B12014-11-25
Attorney, Agent or Firm:
ROSA, Daniele (IT)
Download PDF:
Claims:
CLAIMS

1. A method for automated closing of tubular knitted items at an axial end thereof, said tubular knitted items (1) being preferably manufactured by means of a circular knitting machine (2) for knitted or hosiery items, the method comprising:

manufacturing a tubular knitted item (1) having an edge (100) delimiting an open axial end; wherein, once finished, the tubular knitted item (1) has a back and a front and defines a median plane (P) basically orthogonal to the back and to the front;

arranging the edge (100) on a circumference having a central axis (K-K); wherein the tubular knitted item (1) with the edge (100) arranged on the circumference has a bulge (18) partially developing around the central axis (K-K);

overturning said bulge (18) and associate a first ring-shaped half of the edge (100) to a second ring- shaped half of the edge (100) so that said bulge (18) defines a toe of the tubular knitted item (1);

sewing the two halves of the edge (100) to one another so as to make a seam (16) and close the axial end;

characterized in that the overturning takes place around an overturning axis (Y-Y) which is skew with respect to directions orthogonal to the median plane (P).

2. The method according to claim 1, wherein the overturning axis (Y-Y) lies in a plane orthogonal to the central axis (K-K) of the tubular knitted item (1) and delimits with the directions orthogonal to the median plane (P) an angle (a) different from 0°, wherein said angle (a) is preferably between 5° and 90°, more preferably between 10° and 45°.

3. The method according to claim 1 or 2, wherein the tubular knitted item (1) is symmetrical with respect to the median plane (P); wherein the first ring-shaped half of the edge (100), or the second ring-shaped half of the edge (100), is angularly offset around the central axis (K-K) of the tubular knitted item (1) with respect to a portion of said edge corresponding to the bulge (18).

4. The method according to claim 1 or 2, wherein the tubular knitted item (1) is asymmetrical with respect to the median plane (P); wherein the tubular knitted item (1) has differentiated knitted areas (19A, 19B) placed near the edge (100); wherein the overturning axis (Y-Y) goes through two points (P1, P2) of the edge (100) which delimit a portion of said edge (100) corresponding to the bulge (18).

5. The method according to one of the claims 1 to 4, wherein, by flattening the tubular knitted item (1) so as to place the front or the back on a plane, the seam (16) lies in said plane and is inclined with respect to the directions orthogonal to the median plane (P); wherein ends of the seam (16) are distanced from side edges of the tubular knitted item (1).

6. The method according to one of the claims 1 to 5, wherein the tubular knitted item (1) is a sock or a shoe upper (17), wherein the median plane (P) is orthogonal to an underside of the sock or of the shoe.

7. A sewing or grafting station for automated closing of tubular items at an axial end thereof, said tubular items (1) being preferably manufactured by means of a circular knitting machine (2) for knitted or hosiery items, the station comprising: a sewing or grafting device comprising a sewing or grafting head (8);

a manipulating device (9) comprising:

two half-crowns (10A, 10B) hinged to one another around a diametral axis (Y-Y), wherein the two half-crowns (10A, 10B) are movable under control between a first position, in which they lie in a common plane and define a complete crown extending around a main axis (Z-Z), and a second position, in which one of the two half- crowns (10A; 10B) is turned over the other half-crown (10B; 10A) around the diametral axis (Y-Y);

a plurality of tips (11) supported by the two half-crowns (10A; 10B), wherein in the first position the tips (11) are arranged according to an ideal cylindrical surface; wherein the tips (11) are apt to support an edge (100) of an axial end of the tubular knotted item (1); wherein in the second position each tip (11) of an half-crown (10A; 10B) is facing and aligned with a corresponding tip (11) of the other half-crown (10B; 10A);

characterized in that the manipulating device (9) comprises an adjusting device (15) configured for adjusting an angular position of the two half-crowns (10A; 10B) around the main axis (Z-Z).

8. An apparatus for manufacturing tubular knitted items, comprising:

a circular knitting machine comprising a needle-holding cylinder (3) and/or a needle-holding plate provided with a plurality of needles (4), configured for manufacturing tubular knitted items (1);

a sewing or grafting station according to claim 7;

a conveyor (6) operating between the needles (4) and the sewing or grafting station and configured for taking a tubular knitted item (1) from the needles and (4) engage it to the tips (11).

9. A process for manufacturing tubular knitted items, comprising:

manufacturing a tubular knitted item (1) on the circular knitting machine (2) of the apparatus of claim

8;

adjusting an angular position of the two half-crowns (10A, 10B) around the main axis (Z-Z);

conveying, by means of the conveyor (6) of the apparatus of claim 8 and after adjusting the angular position, the tubular knitted items (1) from the needles (4) to the tips (11) of the manipulating device (9) of the apparatus of claim 8, wherein the two half-crowns (10A, 10B) are in the first position and the tips (11) support the edge (100) of an axial end of the tubular knitted item (1);

shifting the two half-crowns (10A, 10B) to the second position;

sew two halves of the edge (100) to one another by means of the sewing or grafting device.

10. A tubular knitted item, preferably manufactured according to the method of claim 1 and/or the process of claim 9 or with the apparatus of claim 8, wherein the tubular knitted item (1) has a back and a front and a seam (16) made on the back or on the front; wherein, by flattening the tubular knitted item (1) so as to place the front or the back on a plane, the seam (16) lies in said plane and is inclined with respect to directions orthogonal to a median plane (P) of the tubular knitted item (1).

Description:
DESCRIPTION

“A sewing or grafting station and a method for automated closing of tubular items at an axial end thereof”

Field of the invention

The present invention relates to a sewing or grafting station and to a method for automated closing of tubular items at an axial end thereof. The present invention also relates to an apparatus and a process for manufacturing tubular knitted items.

The present invention preferably falls into the field of circular weft knitting machines configured for manufacturing textile items so as to obtain finished products such as socks or, after suitable further processing, shoe uppers.

The present invention further relates to a shoe upper made with a tubular knitted item obtained by means of said method, station, apparatus and/or process.

Background of the invention

It is known about the use of circular weft knitting machines for manufacturing tubular items designed for shoe uppers.

Such tubular items, once manufactured by the knitting machine, typically undergo a series of operations, such as cutting, sewing, application of additional portions, etc., in order to obtain uppers apt to be suitably associated with respective soles for making footwear.

In particular, it is known about automatically closing an end of the tubular knitted item manufactured by the circular loom by means of devices arranged on or near the circular loom itself. The closed end will be the toe of the sock or of the shoe upper.

For instance, document W02009112346 discloses a method and a device for closing a tubular knitted item at one of the axial ends thereof, at the end of its manufacturing cycle on a circular knitting machine for hosiery, knitwear or similar products. The method consists in ending the production of an item at one of the axial ends thereof. The item is then picked up from the machine and moved to a manipulating device located in a sewing or grafting station at a lateral distance from the machine. The item is picked up by singularly transferring the loops of the last knitted course from the machine needles to tips of the manipulating device, which comprises a ring-shaped body consisting of two half-crowns, one of which can be tilted with respect to the other around a diametral axis. The item is then turned and one of the two half-crowns is tilted over the other one, so that the tips of a half-crown are facing and aligned with the tips of the other half-crown. The knitted loops arranged on the tips of a half-crown are transferred to the tips of the other half-crown so that each tip of this latter half- crown supports a pair of knitted loops. Then the pairs of knitted loops are joined by sewing or grafting, closing the axis end of the item engaged onto the manipulating device.

Summary

In the field of the production of socks or shoe uppers by means of knitted machines with automated toe closing, like the one disclosed above, the Applicant has found some drawbacks.

l First of all, the Applicant has observed that opposed terminal ends of known seams extend as far as the lateral edges of the sock and are visible even though this seam is obtained on a sock portion designed to be arranged on the wearer’s foot plant. These ends are aesthetically of little value.

The Applicant has first observed that, if the sock is designed to be the upper of a show, the aforesaid terminal ends of the seam, depending on the type of sole used, can protrude from the sole and not be completely hidden below the latter. Not only is this aesthetically unpleasant, it can also engender technical problems when joining the sole to the upper and/or cause functional problems and/or issued concerning the robustness of the footwear.

Under these circumstances, an aim of the present invention is to improve the quality of manufactured socks or shoes.

In particular, an aim of the present invention is to obtain socks and/or shoes starting from aesthetically and qualitatively valuable tubular knitted items, in which the seam of the toe is totally hidden, in the case of footwear under the sole.

An aim of the present invention is also to prevent the seam of the upper toe from negatively affecting other manufacturing steps of the footwear, in particular when joining the sole to the upper.

An aim of the present invention is also to obtain a seam with such characteristics as to adapt to the type of sole coupled with the upper.

A further aim of the present invention is to propose an apparatus for manufacturing tubular knitted items which is able to automatically sew the toe so that said seam achieves the aims listed above.

Another aim of the present invention is to propose an apparatus for manufacturing tubular knitted items provided with a toe sewing or grafting station which can be easily and rapidly adjusted as a function of the type of seam to be obtained.

These and other possible aims, which shall appear from the following description, are basically achieved by a method, a process, an apparatus and a sewing station that is able to orient/incline the seam made automatically so that its opposed ends are at a distance from the lateral edges of the tubular knitted items and thus, preferably, from the sock/shoe upper.

Some aspects of the invention are listed below.

According to one independent aspect, the invention relates to a method for automated closing of tubular knitted items at an axial end thereof, said tubular knitted items being preferably manufactured by means of a circular knitting machine for knitted or hosiery items, the method comprising:

manufacturing a tubular knitted item having an edge delimiting an open axial end; wherein, once finished, the tubular knitted item has a back and a front and defines a median plane basically orthogonal to the back and to the front;

arranging the edge on a circumference having a central axis; wherein the tubular knitted item with the edge arranged on the circumference has a bulge partially developing around the central axis;

overturning said bulge and associating a first ring-shaped half of the edge to a second ring-shaped half of the edge so that said bulge defines a toe of the tubular item; sewing the two halves of the edge to one another so as to make a seam and close the axial end; wherein the overturning takes place around an overturning axis which is skew with respect to directions orthogonal to the median plane.

According to one independent aspect, the invention relates to a sewing or grafting station for automated closing of tubular knitted items at an axial end thereof, said tubular knitted items being preferably manufactured by means of a circular knitting machine for knitted or hosiery items, the station comprising: a sewing or grafting device comprising a sewing or grafting head;

a manipulating device comprising:

two half-crowns hinged to one another around a diametral axis, wherein the two half-crowns are movable under control between a first position, in which they lie in a common plane and define a complete crown extending around a main axis, and a second position, in which one of the two half-crowns is turned over the other half-crown around the diametral axis;

a plurality of tips supported by the two half-crowns, wherein in the first position the tips are arranged according to an ideal cylindrical surface; wherein the tips are apt to support an edge of an axial end of the tubular knotted item; wherein in the second position each tip of an half-crown is facing and aligned with a corresponding tip of the other half-crown;

wherein the manipulating device comprises an adjusting device configured for adjusting an angular position of the two half-crowns around the main axis.

According to one independent aspect, the invention relates to a tubular knitted item having a back and a front and a seam made on the back or on the front; wherein, by flattening the tubular knitted item so as to place the front or the back on a plane, the seam lies in said plane and is inclined with respect to directions orthogonal to a median plane of the tubular knitted item. Preferably, the seam is inclined with respect to directions orthogonal to the median plane of an angle differing from 0°, preferably of 90° or less, preferably between 5° e 90°, more preferably between 10° and 45°.

In the present invention and in the claims attached thereto,“median plane” of the tubular knitted items refers to the median plane of the finished product, i.e. of the sock or shoe, wherein said median plane is basically orthogonal to a foot plant, intersects heel and toe and basically divides the sock or shoe in two longitudinal halves. This median plane corresponds to the median plane of the tubular knitted item. When the tubular knitted item, after being removed from the machine, is flattened so as to arrange the front and the back on one plane, the median plane is orthogonal to the plane where back and front lie and basically divides the flattened tubular item in two longitudinal halves. The“median plane” is not necessarily a plane of symmetry of the tubular item.

In the present invention and in the claims attached thereto,“bulge” of the tubular knitted item refers to an excess of fabric, usually known as butt, which forms exactly a bulge with respect to an ideal cylindrical surface. When the tubular item is in the machine or hangs from the half-crowns arranged in the first position, this bulge/protrusion radially protrudes from the item (outside or inside). This bulge/protrusion makes it easier to overturn the fabric and make the seam on the item. In the present invention and in the claims attached thereto,“central axis” of the tubular knitted item is the central axis of the tubular knitted item when the latter is shaped as a cylinder, such as e.g. when it is arranged on the needle-holding cylinder and/or on the needle-holding plate of the circular knitting machine. Under these circumstances, the central axis corresponds to the axial symmetry axis of said circular knitting machine. When the tubular knitted item is arranged on the manipulating device, the central axis corresponds to the main axis of the two half-crowns placed in the first position, the overturning axis intersects the central axis and is perpendicular to the central axis.

In the present description and in the claims attached thereto, the wording“intarsia design”, as known in the field of knitwear, relates to a design made up of alternating knitted areas obtained with yarns supplied by one or more feeds of the machine, which does not have floating yarns on the reverse side, i.e. yarns connecting portions of the same knitted course that are at a distance from one another and obtained with their own yarn, and which does not have yarn cutting at the ends of each course portion making up a design area. By way of summary,“intarsia” designs are textile designs with motive, colors and knitted patterns differentiated in the various areas of the item, though without floating yarns on the reverse.

The Applicant has found out that, by adjusting the angular position of the two half-crowns around the main axis before arranging the tubular item on the tips, also the angular position of the overturning axis with respect to the tubular item is adjusted. By arranging the overturning axis skew with respect to the median plane, i.e. not orthogonal to the median plane, the resulting seam does not lie on an arc of circle coaxial with the central axis but is inclined, so that its opposed ends lie at a distance from lateral edges of the tubular item (this is more evident by flattening the tubular item). In other words, the length of the projection of the inclined seam, measured along a circumferential direction, orthogonal to the median plane, is smaller than the length of the seam itself if it lay on said circumferential direction.

In one aspect, the overturning axis lies in a plane orthogonal to a central axis of the tubular knitted item and delimits an angle differing from 0° with the directions orthogonal to the median plane.

In one aspect, said angle is between 5° and 90°. In one aspect, said angle is between 10° and 45°.

In one aspect, adjusting an angular position comprises: turning the two half-crowns around the main axis of an angle differing from 0°, wherein said angle is preferably between 5° and 90°, more preferably between 10° and 45°.

In one aspect and according to some embodiments, the tubular knitted item is symmetrical with respect to the median plane. The median plane defines a plane of symmetry of the tubular knitted item provided with the bulge. This means that the median plane cuts the bulge basically into two halves.

In one aspect, the bulge develops around a central axis of the tubular knitted item on an arc of 180°.

In one aspect, the first ring-shaped half of the edge (or the second ring-shaped half of the edge) is angularly offset around a central axis of the tubular knitted item with respect to a portion of said edge corresponding to the bulge. In other words, the bulge corresponds to an angular portion of the edge that does not coincide exactly with the first ring-shaped half of the edge (or the second ring-shaped half of the edge) which is overturned. The overturning axis does not get across the end points of the angular portion of the edge corresponding to the bulge.

In one aspect and according to some embodiments, the tubular knitted item is asymmetrical with respect to the median plane.

In one aspect according to the preceding aspect, the tubular knitted item has differentiated knitted areas located near the edge. These knitted areas are arranged on the bulge and/or on the remaining part of the tubular item so as to impart the aforesaid symmetry. For instance, with respect to a symmetrical tubular knitted item like the one described above, the asymmetrical tubular knitted item has absent portions and additional portions, so as to impart an asymmetrical aspect also to the bulge which is rotated around the central axis (always with respect to an ideal symmetrical tubular item).

In one aspect, it is provided to manufacture the tubular knitted item with intarsia technique. In one aspect, the aforesaid differentiated knitted areas are manufactured with intarsia technique.

In one aspect according to one of the two preceding aspects, the overturning axis gets across two points on the edge which delimit a portion of said edge corresponding to the bulge. Since the bulge is asymmetrical with respect to the median plane, the overturning axis getting across the aforesaid two points however delimits an angle differing from 0° with the directions orthogonal to the median plane. This angle can also be of 90° (vertical seam). Preferably, this angle is between 5° and 90°, more preferably between 10° and 45°.

In one aspect, the present invention also relates to an apparatus for manufacturing tubular knitted items, comprising:

a circular knitting machine comprising a needle-holding cylinder and/or a needle-holding plate provided with a plurality of needles configured for manufacturing tubular knitted items;

a sewing or grafting station according to one or more of the preceding aspects and/or of the attached claims; a conveyor operating between the needles and the sewing or grafting station and configured for taking a tubular knitted item from the needles and engage it to the tips.

In one different aspect, the present invention also relates to a process for manufacturing tubular knitted items, comprising the steps of:

manufacturing a tubular knitted item on the circular knitting machine of the apparatus according to one or more of the preceding aspects or of the attached claims;

adjusting an angular position of the two half-crowns around the main axis;

conveying, by means of the conveyor of the apparatus according to one or more of the preceding aspects or of the attached claims and after adjusting the angular position, the tubular knitted item from the needles to the tips of the manipulating device of the apparatus according to one or more of the preceding aspects or of the attached claims, wherein the two half-crowns are in the first position and the tips support an edge of an axial end of the tubular knitted item;

shifting the two half-crowns to the second position;

sewing two halves of the edge to one another by means of the sewing or grafting device. In one different aspect, instead of adjusting an angular position of the two half-crowns of the manipulating device, in order to obtain however the overturning around an overturning axis which is skew with respect to directions orthogonal to the median plane, the circular knitting machine is programmed for manufacturing the tubular item rotated, on its needle-holding cylinder and/or on a needle-holding plate, of the desired angle differing from 0°.

In one different aspect, instead of adjusting an angular position of the two half-crowns of the manipulating device, in order to obtain however the overturning around an overturning axis which is skew with respect to directions orthogonal to the median plane, the conveyor is rotated around its main axis after the conveyor has taken the tubular knitted item from the circular knitting machine and before transferring it to the manipulating device.

In one aspect, the present invention also relates to a process for manufacturing a sock, comprising a step of manufacturing a tubular knitted item according to one of the variants of the process as described above.

In one aspect, the present invention also relates to a process for manufacturing a shoe, comprising at least the steps of:

manufacturing a tubular knitted item according to one of the variants of the process as described above, wherein said tubular knitted item defined an upper of the shoe;

joining a sole to a front portion of the upper so as to cover the seam.

Further characteristics and advantages shall be more evident from the detailed description of a preferred, though not exclusive, embodiment of an apparatus and of a process for manufacturing tubular knitted items according to the present invention.

Description of the drawings

This description shall be made below with reference to the accompanying drawings, provided to a merely indicative and therefore non-limiting purpose, in which:

Figure 1 schematically shows a circular knitting machine and a tubular item manufactured by the latter, associated to a conveyor;

Figure 2 shows a schematic perspective view of a manipulating device;

Figures 3A-3C schematically show the manipulating device and the tubular item in respective operating configurations;

Figure 4 shows the tubular item hanging from its upper edge;

Figure 5 is a top view of the tubular item of Figure 4;

Figure 6 shows the tubular item of Figures 4 and 5 in a partially overturned configuration of the toe; Figure 7 is a front view of the tubular item of Figure 6;

Figure 8 shows the tubular item of Figures 4-7 with the toe sewn and flattened;

Figure 9 shows a variant of the tubular item hanging from its upper edge;

Figure 10 is a top view of the tubular item of Figure 9;

Figure 11 shows the tubular item of Figures 9 and 10 in a partially overturned configuration of the toe; Figure 12 is a front view of the tubular item of Figure 11 ;

Figure 13 shows the tubular item of Figures 9-12 with the toe sewn and flattened;

Figure 14 shows a joining step of a sole to the tubular item shaped as a shoe upper.

Detailed description

With reference to the figures mentioned, the numeral 1 globally designates a tubular knitted item manufactured on a circular knitting machine 2 schematically represented in Figure 1. The circular knitting machine 2 can be known per se and therefore has not been described here in detail. The circular knitting machine 2 comprises a needle-holding cylinder 3 equipped with a plurality of needles 4 arranged as a circular crown around a main axis“X-X” of the needle-holding cylinder 3 and facing upwards. The circular knitting machine 2 manufactures the tubular knitted item 1 , which progressively falls into the needle-holding cylinder 3, as shown in Figure 1.

The circular knitting machine 2 is part of an apparatus for manufacturing tubular knitted items, which further comprises a sewing or grafting station 5 (partially and schematically represented in Figure 3C) and a conveyor 6 (schematically shown in Figure 1).

The sewing or grafting station 5 is configured for automated closing of an axial end of the tubular knitted items 1 manufactured on the circular knitting machine 2. The conveyor 6 is operating between the needles 4 and the sewing or grafting station 5 and is configured for taking the tubular knitted item 1 from the needles and 4 move it near the sewing or grafting station 5.

The conveyor 6 is of the type shown by way of example in patent application W02009112346 and comprises a body shaped as a circular crown, having a plurality of grooves, not shown, inside each of them a picking mechanism 7 being arranged (only two are schematically visible in Figure 1). The body of the conveyor 6 supports as many picking mechanisms 7 as the needles 4 of the circular knitting machine 2. The conveyor 6 is supported by a powered arm, not shown, which is movable between a pickup position and a release position. In the pickup position, the body of the conveyor 6 is arranged coaxially to the needle-holding cylinder 3 (Figure 1). In the release position, the body of the conveyor 6 is arranged on the sewing or grafting station 5 (Figure 3A). In the pickup position of Figure 1 , each picking mechanism 7 of the body of the conveyor 6 engages with the corresponding needle 4 and devices that are not shown cause the transfer of single knitted loops of the tubular knitted item 1 from the needles 4 to the picking mechanisms 7.

The sewing or grafting station 5 comprises a sewing or grafting device comprising a sewing or grafting head 8 (schematically shown in Figure 3C). The sewing or grafting station 5 further comprises a manipulating device 9 (visible in Figures 3A-3C).

The structure of the manipulating device 9 can be as the one described in W02009112346.

The manipulating device 9 comprises a circular crown body 10 arranged with its main axis“Z-Z” in vertical position. The circular crown body 10 is provided on its lower face with a plurality of tips 11 arranged according to an ideal cylindrical surface whose axis coincides with the main axis“Z-Z” of the circular crown body 10. The tips 11 are as many as the picking mechanisms 7 and are apt to support an edge 100 of an open axial end of the tubular knitted item 1. The circular crown body 10 is made up of two half-crowns 10A, 10B hinged one to the other around a diametral or overturning axis Ύ-U”. The two half-crowns 10A, 10B are movable under control and by means of an actuator, not shown, between a first position (Figures 2, 3A and 3B), in which they lie in a common plane and define a complete crown, i.e. the circular crown body 10, extending around the main axis“Z-Z”, and a second position (Figure 3C), in which one of the two half-crowns is turned over the other half-crown around the diametral or overturning axis Ύ-U”.

In the first position, the tips 11 are arranged according to the ideal cylindrical surface and in the second position (Figure 3C) each tip 11 of a half-crown 10A; 10B is facing and aligned with a corresponding tip 11 of the other half-crown 10B; 10A.

In the release position mentioned above, the body of the conveyor 6 is located coaxially with the circular crown body 10 arranged in the first position (Figure 3A). In this mutual position, devices that are not shown cause the transfer of single knitted courses of the tubular knitted item 1 from the picking mechanisms 7 to the tips 11. Once this transfer has been carried out, the tubular knitted item 1 hangs from the tips 11 (Figure 3A). The manipulating device 9 is associated with a turning unit 12 comprising a cylindrical body 13 and a tubular body 14. The cylindrical body 13 is arranged with its open lower end inside the circular crown body 10. The tubular body 14 can be inserted from below into the circular crown body 10 and into the cylindrical body 13 so as to turn the tubular knitted item 1 while it hangs from the tips 11 (Figures 3A and 3B). Also the structure of the turning unit 12 can be as the one described in W02009112346. Once the turning operation has been carried out, the tubular knitted item 1 is arranged around the tubular body 14 with the edge 100 of the axial end held by the tips 11 (Figure 3B).

After the turning operation, one of the two half-crowns 10A; 10B is turned over the other half-crown 10B; 10A around the diametral or overturning axis Ύ-U” (Figure 3C). In the second position, devices that are not shown cause the transfer of single knitted loops of the tubular knitted item 1 from the tips 11 of the upper half-crown 10A to the tips 11 of the lower half-crown 10B.

Unlike what is disclosed in W02009112346, the manipulating device 9 comprises an adjusting device 15, schematically shown in Figure 2, configured for adjusting an angular position of the circular crown body 10, i.e. of the two half-crowns 10A, 10B around the main axis“Z-Z”. The adjusting device 15 comprises a motor and, if necessary, further mechanisms configured for rotating and blocking in a selected angular position the circular crown body 10 around the respective main axis“Z-Z”.

The apparatus for manufacturing tubular knitted items 1 as shown is able to manufacture a tubular knitted item 1 and to close in an automated manner the axial end of the tubular knitted item 1 by means of an inclined seam 16, as will be explained later in further detail and according to the method for automated closing of tubular knitted items at an axial end thereof and to a process for manufacturing tubular knitted items according to the invention.

The tubular knitted item 1 shown in Figures 4 to 8 and in the variant of Figures 9-13 is a finished sock or a sock designed, after being shaped and possibly undergoing further processing, to form an upper 17 of a shoe, such as shown by way of example in Figure 14. The tubular knitted item 1 is manufactured on the circular knitting machine 2 so as so have an excess of fabric or bulge 18 which, if the edge 100 of the tubular knitted item 1 is arranged on an ideal circumference as in Figure 4, forms a bulge/protrusion with respect to an ideal cylindrical surface and this bulge 18 radially protrudes inside the tubular knitted item 1 (Figures 4 and 5). For instance, the bulge 18 is obtained on the circular knitting machine 2, also in a manner known per se, by means of an intarsia technique. Figures 4 to 7 and 9 to 12 have been added so as to explain the ideas expressed here, but they do not correspond to any real processing step. In Figures 6 and 11 it is as if a portion of the edge 100 of the item were pulled upwards so as to stretch the bulge 18. In Figures 1, 3A, 3B and 3C this bulge 18 is schematically shown.

The tubular knitted item 1 of Figures 4 to 8 has a plane of symmetry“P” containing a central axis“K-K”. The bulge 18 develops on a 180° arc symmetrically to the plane of symmetry“P” and corresponds to a 180° angular portion of the edge 100 (Figure 5). A diametral axis“O-O” orthogonal to the median plane“P” gets across two end points of the angular portion of the edge corresponding to the bulge 18. The plane of symmetry“P” coincides with a median plane“P” of the finished product, i.e. of the sock or shoe, wherein said median plane“P” is basically orthogonal to a foot plant, intersects heel and toe and basically divides the sock or shoe in two longitudinal halves. The tubular knitted item 1 has a back and a front, wherein the front corresponds to the foot plant. When the tubular knitted item 1, after being removed from the machine 2, is flattened so as to arrange the front and the back on one plane (as in Figure 8), the median plane“P” is orthogonal to the plane where back and front lie and basically divides the flattened tubular item 1 in two longitudinal halves.

The conveyor 6 takes the tubular knitted item 1 from the machine 2 (Figure 1) and hangs it from the tips 11 of the manipulating device 9 (Figure 3A) so that the diametral axis“O-O” of the tubular knitted item 1 does not coincide with the diametral or overturning axis Ύ-U” of the circular crown body 10. In particular, the overturning axis Ύ-U” intersects the central axis“K-K” and delimits with the diametral axis“O-O” of the tubular knitted item 1 an angle“a” differing from 0°, e.g. of at least 30° (Figure 5). This angle can also be of 90°. The overturning axis Ύ-U” lies in a plane orthogonal to a central axis“K-K” of the tubular knitted item 1 and is skew with respect to a direction orthogonal to the median plane“P”.

This angle“a” can be set by adjusting with the adjusting device 15 the angular position of the circular crown body 10 around the main axis“Z-Z” before the conveyor 6 transfers the tubular knitted item 1 to the manipulating device 9. With respect to an angular position in which the diametral axis“O-O” of the tubular knitted item 1 coincides with the diametral or overturning axis Ύ-U” of the circular crown body 10, the circular crown body 10 is rotated of the aforesaid angle“a” and blocked in this rotated position.

Now the two half-crowns 10A, 10B are brought to the second position (Figure 3C) by overturning the half- crown 10B located on the side of the bulge 18 under the other half-crown 10A and this movements involves the bulge 18 being overturned. A first ring-shaped half of the edge 100 supported by the tips 11 of a half- crown 10A is associated to a second ring-shaped half of the edge 100 supported by the tips 11 of the other half-crown 10B. Said first and second ring-shaped halves of the edge 100 are divided by the overturning axis “0-0”. It is this bulge/protrusion 18 that makes it easier to create the inclined seam of the tubular knitted item 1

It should be noted that the first ring-shaped half of the edge (or the second ring-shaped half of the edge) is angularly offset around the central axis“K-K” of the tubular knitted item 1 with respect to the portion of said edge corresponding to the bulge 18. The bulge 18 corresponds to an angular portion of the edge 100 that does not coincide exactly with the first ring-shaped half of the edge (or the second ring-shaped half of the edge) which is overturned. In other words, the overturning axis Ύ-U” does not get across the end points of the angular portion of the edge corresponding to the bulge 18.

The knitted loops of the tubular knitted item 1 of the tips 11 of the upper half-crown 10A are associated with the knitted loops of the tubular knitted item 1 of the tips 11 of the lower half-crown 10B according to the lines shown by way of explanation in Figure 7. As can be noted from Figure 7, due to the angle“a”, in the lateral area on the left (with reference to Figure 7) a loop of the angular portion corresponding to the bulge is associated with another loop still belonging to this angular portion. In the lateral area on the right, a loop of the remaining angular portion (not corresponding to the bulge) is associated with another loop still belonging to this remaining angular portion.

The sewing or grafting head 8 is actuated so as to sew one to the other the first ring-shaped half of the edge 100 and the second ring-shaped half of the edge 100.

The resulting seam 16 does not lie along a circumferential line of the tubular knitted item 1 but is inclined. By removing the tubular knitted 1, now having a toe closed by the manipulating device 9, and flattening it so as to arrange the front in a plane (Figure 8), the seam 16 lies in said plane and is inclined with respect to directions orthogonal to the median plane“P” of the tubular knitted item 1.

In the variant of embodiment shown in Figures 9 to 13, the tubular knitted item 1 is manufactured on the circular knitting machine 2 so as to be asymmetrical with respect to the median plane“P”.

The asymmetrical tubular knitted item 1 has differentiated knitted areas located near the edge 100 on the bulge 18 and/or on the remaining part of the tubular item 1 so as to impart the aforesaid asymmetry to the latter. Figure 11 shows, by way of explanation, with a dashed line the symmetrical tubular knitted item 1 described above and with a solid line the shape of the asymmetrical tubular knitted item 1 of the variant of embodiment. As can be noted, the asymmetrical tubular knitted item 1 has additional knitted areas 19A and absent knitted areas 19B (these latter areas 19B are shown for clarity’s sake but are actually not present). As can be noted, as a result of the additional knitted areas 19A and of the absent knitted areas 19B, the bulge 18 is rotated around the central axis“K-K” with respect to an ideal symmetrical tubular item. The aforesaid differentiated knitted areas are manufactured e.g. with intarsia technique.

The asymmetrical tubular knitted item 1 is manufactured so that the rotation of the bulge 18 (with respect to the symmetrical configuration) corresponds to the desired rotation of the overturning axis Ύ-U”. The overturning axis Ύ-U” coincides with a diametral axis of the asymmetrical tubular knitted item 1 getting across two points P1, P2 of the edge 100 which delimit a portion of said edge corresponding to the bulge 18 (Figures 11 and 12). In other words, the bulge 18 corresponds to an angular portion of the edge 100 that coincides exactly with the first ring-shaped half of the edge (or the second ring-shaped half of the edge) which is overturned.

By means of the adjusting device 15, the angular position of the circular crown body 10 around the main axis “Z-Z” is set as a function of the rotation of the bulge 18 before the conveyor 6 transfers the tubular knitted item 1 to the manipulating device 9.

The conveyor 6 takes the tubular knitted item 1 from the machine 2 (Figure 1) and hangs it from the tips 11 of the manipulating device 9 (Figure 3A) so that the diametral axis of the asymmetrical tubular knitted item 1 coincides with the diametral or overturning axis Ύ-U” of the circular crown body 10.

Now the two half-crowns 10A, 10B are brought to the second position by overturning the half-crown 10B located on the side of the bulge 18 under the other half-crown 10A and this movements involves the bulge 18 being overturned.

The knitted loops of the tubular knitted item 1 of the tips 11 of the upper half-crown 10A are associated with the knitted loops of the tubular knitted item 1 of the tips 11 of the lower half-crown 10B according to the lines shown by way of explanation in Figure 12.

As can be noted from Figure 12, each loop of the angular portion corresponding to the bulge is associated with a respective loop of the remaining angular portion.

The sewing or grafting head 8 is actuated so as to sew one to the other the first ring-shaped half of the edge 100 and the second ring-shaped half of the edge 100.

The resulting seam 16 does not lie along a circumferential line of the tubular knitted item 1 but is inclined. By removing the tubular knitted 1, now having a toe closed by the manipulating device 9, and flattening it so as to arrange the front in a plane (Figure 13), the seam 16 lies in said plane and is inclined with respect to directions orthogonal to the median plane“P” of the tubular knitted item 1.

In variants of embodiment both with symmetrical and asymmetrical tubular knitted item, instead of setting the angular position of the circular crown body 10 around the main axis“Z-Z”, the conveyor 6 is rotated around its main axis after the conveyor 6 has taken the tubular knitted item from the circular knitting machine 2 and before transferring it to the manipulating device 9.

In further variants of embodiment both with symmetrical and asymmetrical tubular knitted item, instead of setting the angular portion of the circular crown body 10 around the main axis“Z-Z”, the circular knitting machine 2 is programmed for manufacturing the tubular item rotated on its needle-holding cylinder and/or a needle-holding plate of the desired angle differing from 0°.

If the tubular knitted item 1 with closed toe is designed to be the upper 17 of a shoe, it undergoes further processing aiming e.g. at imparting a stable shape with more or less stiff parts to the item. The upper 17 thus manufactured has a plant on which the inclined seam 16 is arranged. The plant is joined, e.g. by gluing, a sole 20 so as to fully cover the seam 16 (Figure 14).

The invention achieves important advantages.

The inclination of the seam allows to improve the quality of manufactured socks or shoes, since this seam can be completely hidden under the foot plant or by the upper in the case of shoes. The invention further allows to set the inclination of the seam depending on other size or shape features of the sock and/or on the size and type of sole coupled with the upper.

Moreover, by manufacturing an asymmetrical tubular knitted item it is possible to shape the edge so as to adapt it to the inclination of the seam. Thus the creation of the seam does not involve high deformations of the adjacent knitted areas and the manufactured articles has superior quality and appearance.

The apparatus according to invention allows to create an inclined seam in a simple and flexible manner.