WO2010086708A1

WO2010086708A1 - Device for drawing a sock from a cylindrical machinery for the production of tubular manufacture with seamed end

Info

Publication number: WO2010086708A1
Application number: PCT/IB2010/000137
Authority: WO
Inventors: Paolo Conti; Ferdinando Rossi
Original assignee: N.T.A. S.R.L.
Priority date: 2009-01-30
Filing date: 2010-01-27
Publication date: 2010-08-05
Also published as: ITFI20090021A1; TW201037115A; IT1392646B1

Abstract

The present invention concerns a unit of production of knitted tubular, such as socks and similar. In particular, it refers to a device for drawing the manufacture and generally made up of an arm (1), a drawing element (5) comprising means of grasp of the fabric (11) of the manufacture and means (4, 10) for moving the arm between a position external to a crown of needles (2) of the cylindrical machine that realizes the manufacture and a position coaxial to it in which the means of grasp (11) result bound on the knitted tubular to draw it and vice- versa. In particular, according to the invention, the means of grasp comprise a crown of fixed hooks (11) set in such a way so that following the lowering of the drawing element on the tubular, the hooks penetrate the stitching realizing its grasp.

Description

TITLE

DEVICE FOR DRAWING A SOCK FROM A CYLINDRICAL MACHINERY FOR THE PRODUCTION OF TUBULAR MANUFACTURE WITH SEAMED END

Technical Field

The present invention concerns the technical field relative to the production of fabric tubular manufacture, such as socks or similar. In particular, it refers to a device that allows the drawing of the sock from the cylindrical machine that realizes it and its subsequent transfer to the sewing section used for the closure of the toe.

It is also described here the relative method for realizing the closure of the manufacture. State of the Art

Circular machines for the production of tubular manufacture, such as socks and similar, have long been known. According to the state of the art, the cylindrical machine is provided with a crown of needles in combination with a crown of sinkers and controlled in such a way as to allow the realization of the tubular in fabric. In particular, the rotation of the cylinder generates an alternate movement (generally up/down) of the needles by means of appropriate cams. The movement of the needles in combination with the radial motion of the sinkers ^'thus develops the tubular in length and, once the pre- established length is reached, its closure in correspondence of the toe is carried out. Older types of machineries are not furnished with any specific section for such an operation of sewing of the toe. For that purpose, specialized operators are therefore employed for doing by hand (eventually with the help of ordinary domestic sewing machines) such an operation. The significant technical inconveniences, if such a solution is adopted, are clear. Above all, the productive performance is low, since the manufacture must be drawn by hand from the machine that realizes it to be then placed in correspondence of the appropriate sewing machine. Moreover, the manual execution of the seam is often slow, all of which reflects on a productive fall and a significant increase in additional staff costs.

In order to solve all the above-mentioned inconveniences, alternative solutions that are present in the market propose automated sewing machines integrated to the machinery itself. Thus, the sewing machine actively intervenes in the productive cycle of the tubular, making the presence of operators for such a function absolutely unnecessary. Nevertheless, the integration of a sewing section implies structural complications of the machinery as a whole and that inevitably imply higher costs, both of purchase and of ordinary maintenance.

Moreover, for those who already have old machines that do not have sewing devices, there is no possibility whatsoever of adapting them. The only possibility is the complete substitution of those machines with more evolved ones, like the ones mentioned above . In order to find a solution to the said problems of structural complication, devices for drawing external to the machinery and suitable for transporting the manufacture and other external sections for the seam have been idealized. A device for drawing thus allows to remove the tubular formed by the cylinder of needles (once the pre-established length is reached) and translate it towards an external zone in which a dedicated sewing machine is placed. Thus, it is possible, for example, to adapt old machineries that lack sewing device in an economical manner. Although the present devices for drawing are functionally efficient and of high performance, they present a level of structural complication that is not indifferent and that strongly bears both on the purchase costs of them and on their maintenance. Some solutions propose, for example, mobile hooks that realize the grasp and the drawing of the manufacture substantially in correspondence of the needles. The hooks are moved by complex operating systems, generally of extraction/retraction type, that must be perfectly synchronized with respect to the movement of the needles of production of the manufacture. It is clear how such a solution is extremely complex, since it requires high precision kinematic motion in order to catch the stitch in correspondence of the needles. Moreover, the movement of the hooks causes the wear of the parts and therefore, frequent adjustments. The whole means additional maintenance costs. Brief description of the invention It is therefore the aim of the present invention to provide a device for drawing the manufacture that is constructively simple in such a way as to guarantee a higher functioning reliability and at the same time reduce the maintenance costs relative to the machinery itself.

It is also the aim of the present invention to provide a device for drawing that is low-cost, in virtue of its structural simplification, in such a way as to allow advantageous integrations in already existing machineries.

These and other aims are therefore reached with the present device for drawing a knitted tubular manufacture realized by a cylindrical machine (3) , such as socks or similar, the said device comprising means of grasp (6, 11) comprising a supporting element (6) for a plurality of hooks (11) for realizing the grasp of the manufacture and configured in such a way to result movable between a position external to the cylindrical machine and a position coaxial to it in which the said hooks (11) result bound on the knitted tubular to draw it and vice-versa and characterized by the fact that the hooks (11) are fixed and configured in such a way as to penetrate the stitches realizing the grasp .

It is clear how such a configuration is structurally simple, and thus allows a significant save in production and/or maintenance costs. The hooks are indeed fixed and therefore lack any control kinematic motion. By simply lowering the device for drawing below the tubular manufacture (or, alternatively, the supporting element on which they are rigidly connected) they perforate the stitch penetrating it and realizing the grasp.

Therefore, according to a possible constructive solution, the fixed hooks (11) are placed on the peripheral side of a crown (6) according to such a circular configuration that, following the lowering of the device for drawing, they perforate the tubular manufacture along its periphery in correspondence of the last ranks with respect to the knitting needle (2) .

Such a solution allows therefore an arrangement of the hooks that does not require high-precision positioning, since they grab the stitch far from the needles and not necessarily stitch by stitch. It is therefore clear how it is not necessary anymore not only kinematic motion of opening-closure, but neither kinematic motion that requires such a high-precision calibration as to allow to grasp the stitch precisely in correspondence of the needles. In particular, according to a possible configuration, the needles can penetrate the stitch approximately the last four or five ranks. It is clear how the whole means a significant save in realization costs.

Naturally, alternative solutions, as already said, can comprise the lowering of the group relative to the crown (6) only.

More in detail, the crown (6) is arranged at an end of an arm (1'), the said arm being operable by a rack and pinion coupling.

The arm can therefore translate according to a possible constructive solution.

Preferably, the arm (1) is shaped according to an approximate L shape and is hinged around the rack (4) on the side opposite to the crown (6) , the said rack being placed in combination with the pinion (10) in such a way that the operation of the pinion (10) with respect to the rack (4) allows the rotation of the arm around the rack.

Advantageously, in order to allow to liberate the hooks from the grasped manufacture, an unhooking device (13) is provided, operable according to an alternate up/down motion after the sewing.

It is further described here a unit for the production of knitted tubular, such as socks and similar, and comprising: - A cylindrical body (3) comprising a crown of needles (2) and sinkers (12) for the formation of the knitted tubular;

- A device for drawing (1) the knitted tubular manufacture comprising means of grasp (6, 11) comprising a supporting element (6) for a plurality of hooks (11) for realizing the grasp of the manufacture, the device being configured in such a way as to be able to be moved between a position external to the said cylindrical machine and a position coaxial to it in which the said hooks (11) result bound on the knitted tubular to draw it and vice-versa;

- A sewing machine (17) placed in correspondence of the said external position to allow the closure of the toe of the tubular; and characterized by the fact that the hooks (11) are fixed and configured in such a way that, following the approach of the device for drawing towards the tubular, the said hooks penetrate ' the knitting realizing the grasp.

It is also described a method for the realization of a knitted tubular manufacture comprising the operations of:

- Formation of a tubular stitch starting from the edge and finishing with the toe by means of a tubular cylindrical machine comprising in combination a cylinder of knitting needles (2) and sinkers (12);

- Insertion of a drawing element (5) in the knitted tubular in formation and release of the needles from the said stitch in such a way as to allow the grasp of the tubular;

- Removal of the tubular stitch and transportation to a sewing section (17) ;

- Closure of the toe with the said sewing machine (17) ; and characterized by the fact that the said operation of insertion of the drawing element comprises the approach of a crown of fixed hooks (11) towards the tubular in such a way that the said hooks pierce the stitching, grasping them and allowing their removal from the cylindrical machine.

Advantageously, the approach comprises the operation of lowering of the drawing element (5) on the tubular.

Alternatively, it is here described a further method for the realization of a knitted tubular manufacture comprising the operations of: - Formation of a tubular stitch starting from the edge and finishing with the toe by means of a tubular cylindrical machine comprising in combination a cylinder of knitting needles (2) and sinkers (12) ; - Arrangement of a drawing element (5) above the knitted tubular in formation;

- Hooking of the tubular formed by means of means of grasp of the fabric (11) of the manufacture arranged on the said drawing element; - Removal of the said tubular stitch and transportation to a sewing section (17);

- Closure of the toe with the said sewing machine (17); characterized by the fact that the said operation of hooking of the tubular comprises the operation of release of the needles (2) of the stitch so that the elastic return effect of the toe of the said tubular projects the edge relative to the said toe against a crown of fixed hooks (11) arranged above the drawing element in such a way that the hooks pierce the stitching.

Brief description of the drawings

Further characteristics and the advantages of the device for drawing the tubular, according to the invention, will be clearer with the description of one of its embodiments that follows, made to illustrate but not limit, with reference to the annexed drawings, in which:

- Figure 1 shows a top view of the rotating arm (1') that realizes the drawing of the manufacture (15) of the cylindrical machinery towards the sewing machine (17) and vice-versa;

- Figure 2 shows a view representing the rotating arm rotated in correspondence of the crown of needles (2) , in such a way as to position the hooks above the circular edge of the sock in coaxial position; - Figure 3 shows the phase in which the hooks of the crown are lowered penetrating the last ranks and grasping the stitching of the sock;

- Figure 4 shows a detailed view representing the grasping hooks and the needles in lowered position;

- Figure 5 shows a plane view of a front view relative to the needles 2, sinkers and grasping hooks on the tubular;

- Figure 6 and figure 7 show the phase of release of the needles;

- Figure 8 shows the phase of lifting of the arm for the removal of the sock from the cylindrical machine;

- Figure 9 shows the rotation that took place in correspondence of the position occupied by the sewing machine and in which the conduct that overturns the tubular is placed.

- Figure 10 and figure 11 show the phase of sewing on the reverse side of the sock.

Description of a preferred embodiment With reference to figure 1 and figure 2, a unit for the production of tubular stitch comprises, as its more basic elements, a cylindrical machine 3 for the production of the tubular (see figure 1 and detail of figure 2), a device for drawing 1 of the manufacture (see figure 1) , a device for reversing/straightening 16 and a sewing machine 17 used for closing the toe of the manufacture, all of them arranged externally with respect to the machine 3 itself.

With particular reference to figure 2, the cylindrical machine 3 that realizes the sock 15 or the tubular in general, essentially comprises a rotating cylinder of needles 2 arranged around a supporting cylinder 3' that supports a crown of sinkers 12. In a well-known manner from the state ^" of the art, therefore, the needles are controlled in such a way as to convey them an alternate motion (generally up-down) that determines the realization of the knitted tubular. For that purpose, the needles are arranged in combination with appropriate cams (not represented in the figure for the sake of descriptive simplicity) in such a way that the rotation of the supporting cylinder 3 conducts the cams themselves in contact with the needles, determining their alternate motion. The tubular thus realized develops inside the cylindrical cavity of the supporting cylinder, where it is aspirated.

The device for drawing 1 according to one of its possible embodiments (see figure 1 for that purpose) comprises a rotating arm 1', generally L-shaped, and pivoted by one of its free ends 4. In such a manner, the arm is capable of rotating around the said point so as to operate within a determined area of action. The opposite end is provided with a specific drawing element 5 comprising a supporting element 6 for means of grasp 11 of the manufacture. In particular (see figure 2) , a commonly used solution foresees a circular crown 6 subdivided in two halves 7 and 8, respectively hinged in correspondence of the point 9. The peripheral part of the circular crown 6 serves as support for a series of fixed hooks 11 (defining a crown of hooks) arranged in correspondence of the periphery of the crown.

Always as highlighted in figures 1 and 2, the half 7 of the crown results fixed to the structure of the rotating arm, while the half 8 can be rotated in such a way so that it overlaps the said half 7. Appropriate means of rotation control such kinematic motion, the functionality of which will anyway be explained more clearly later in this description.

Going back to figure 1, the hinge point 4 of the rotating arm is constituted by a rack 4 for engaging with a pinion 10. Thus, the simple translation of the pinion in the direction of the arrows indicated in the figure allow to control the rotation of the arm from the cylinder of needles 2 towards to sewing machine 17 and vice-versa (the figure referred to represents indeed these two extreme positions) .

A pulley device 12 and belt 13 allows to control the rotation of the circular crown 6 in such a way as to appropriately set in phase the fixed hooks 11 with respect to the rotation of the cylinder of needles 2 and of the sinkers 12. Means for moving (not represented in the figure for simplicity purposes but well-known according to the state of the art) allow then to control the lifting and lowering of the arm in such a way as to allow it both to approach the manufacture, allowing the hooks to penetrate the stitching and therefore to grasp the manufacture, and to lift it from the machine towards the sewing machine. A simple piston device can perform such a function . An unhooking device 13 of the stitch ,(see figure

2) is then arranged on a side of the crown 6, in particular on the fixed part 7. This comprises an unhooking lever 13' , alternatively mobile in the direction up/down and this means from/towards the stitch grasped to the hooks after its sewing. Its functionality will be later explained in detail in the operative part.

Naturally, absolutely equivalent drawing devices can be realized without for this moving apart from the present inventive concept. For example, as an alternative to the rotating arm, a translating device can be thought of always with a rack and pinion coupling and, identically as the precedent one, it can be furnished with fixed hooks for the drawing of the manufacture. However, the arm device described above is only minimally an encumbrance relatively to the phase of insertion in the cylindrical machine. Alternatively, equivalent supporting elements 6 for the fixed hooks can perfectly be realized, without for this moving apart from the present inventive concept. Structurally described in its more basic aspects, the procedure of functioning of the whole unit can therefore be summarized according to the following relevant operating phases .

Initially, the cylinder of needles 2, in combination with the sinkers 12, realizes the knitted tubular according to the alternate movement up/down controlled by the cams and commonly known in the state of the art. The tubular, during its formation, is aspirated in an almost permanent manner inside the cylindrical seat relative to the cylinder 3 (see figure 2 for that purpose) . Once the pre-set length is obtained, the needles lower without leaving the stitch. Contemporarily, the thread-guide group (not represented in the figure just for simplicity purposes) rises to allow the insertion of the rotating arm 1 in the position coaxial to the cylinder of needles (see figure 1 for that purpose and in particular figure 2) . For that purpose, an appropriate control device operates therefore the pinion 10 which, appropriately engaging with the rack 4, causes the rotation of the arm 1 in such a way as to conduct it in correspondence of the cylinder of needles . In this phase, the crown of fixed hooks 11 is placed in rotation in phase with respect to the needles and to the sinkers 12.

The subsequent phase (see figure 3) foresees therefore the lowering of the circular crown 6 in correspondence of the tubular and, for that purpose, the said translation means are opportunely operated, which lower the arm 1' . The operation of lowering causes therefore the insertion of the fixed hooks 11 inside the stitching of the sock in the cavities defined between sinker and sinker in an alternate manner. The hooks pierce, that is perforate or penetrate the stitch, realizing a strong and safe grasp as a consequence. Naturally, for that purpose the circular crown 6 is provided with an opportunely reduced diameter with respect to the diameter relative to the cylinder of needles 2 in such a way that the hooks do not interfere with the needles themselves . In particular, the grasp is carried out in correspondence of the last ranks of stitch, particularly in the last three, four or five ranks.

A detailed enlarged view (see figure 4) shows the grasp of the hooks 11 in correspondence with the last ranks while the needles 2, in this phase, have not left yet the stitch 11 and occupy a lowered position with respect to the sinkers. Figure 5, just for greater clarity purposes, shows a front view plane that highlights the lowered needles with respect to the sinkers and the hooks 11 that have perforated the stitch.

The subsequent phase (see figure 6) therefore foresees the release of the stitches by the needles 2 in such a way that the tubular results entirely held by the cylinder of hooks 11. The detail of figure 7 shows approximately the shape of a hook that has penetrated the stitch and holds it upstream of the drawn thread work 14 which, by elastic return effect, retracts behind the hook with the last ranks collected on it. The drawn thread work 14, as it is well known, is realized with the aim of preventing the garnetting of the thread at the edge of the sock.

The rotating arm can, at this stage, be lifted with respect to the crown of needles 2 in such a way as to make the hooked tubular rise as a consequence (see figure 8) . The rotation of the arm extracts completely the sock from the cylinder 3 and conducts the tubular in position corresponding to the sewing machine (see figure 1 and figure 9) and in which a cylinder of turning over/straightening 16 (see figure 9) is arranged placed above the rotating arm itself, positioned over the rotating arm itself. In this phase, the aspiration that allows to turn over the tubular before carrying out the sewing is therefore operated. Thus, the seam will be carried out from the inside of the sock, that is from the reverse side.

In an absolutely known manner according to the state of the art (see figure 10) , the spreading out flat of the portion 8 on the 7 (see figure 7) is carried out, relatively to the crown 6 so as to overlap the two strips of sock and proceed with the normal sewing to close the toe. Figure 11, just for clarity purposes, enlarges the view relative to the overlapped hooks that grasp upstream the drawn thread work 14 and the knitting needle. Finished the closure, the knitting needle is put away and the release of the hooks 11 from the closed sock is carried out. For that purpose, it is therefore foreseen the subsequent rotation of the portion 8 to re-set the crown to its initial annular geometry (phase not represented just for simplicity purposes) . The rotational motion of the said portion determines the automatic disjunction of the ranks from the hooks relative to such a portion 8. In order to complete the disjunction of the semi-crown of fixed hooks relative to the fixed portion 7, the lowering of the unhooking lever 13 is carried out so as to intercept the tubular and cause its disjunction.

A method of alternative functioning according to what was described can foresee the utilization of the elasticity of the material itself of realization of the tubular. The last turns of rank are indeed carried out with an elastic material, such as Lycra. Thus, it is not necessary anymore to pierce the stitches with the hooks 11 for the grasp. Simply by arranging the said crown 6 above and in proximity of the crown of needles 2 (see position represented in figure 2, for example) , it will be enough to operate the release of the needles . The elastic return effect of the material will conduct the stitches towards the hooks that will pierce automatically, realizing therefore also in this case a strong grasp. For that purpose, the hooks must be opportunely shaped so that their ends are radially protruding towards the outside of the crown 6.

It is at this stage clear how all the aims established by the present invention have been reached. In particular, it is clear how the crown 6 of fixed hooks 11 realizes a constructively simple and efficient grasp device. No kinematic motion is present anymore so as to reduce drastically the maintenance costs, the risks of breakage and the cost of the machinery itself.

The description above of a specific embodiment is capable of showing the invention from the conceptual point of view so that others, by using the state of the art, will be able to modify and/or adapt in different applications such a specific embodiment without further researches and without moving apart from the inventive concept and therefore, it is intended that such adaptations and modifications will be considered as equivalent to the specific embodiment. The means and the materials to realize the different functions described may be of different nature without for this leaving the field of the invention. It is intended that the expressions or the terminology used have a purely descriptive aim and it is therefore not limiting.

Claims

1. Device for drawing a knitted tubular manufacture realized by a cylindrical machine (3) , as socks or similar, said device comprising means of grasp (6, 11) comprising a supporting element (6) for a plurality of hooks (11) able to realize the grasp of the manufacture and set in such a way as to be movable between a position external to said cylindrical machine and a position coaxial to it where said hooks (11) result bound on the knitted tubular to draw it and vice-versa and characterized by the fact that the said hooks (11) are fixed and configured such that to penetrate the stitching realizing the grasp.

2. Device for drawing a knitted tubular manufacture, according to claim 1, wherein the said fixed hooks (11) are placed on the peripheral part of a crown (6) according to such a circular configuration that, following the lowering of the said drawing device, the said hooks perforate the tubular manufacture along its periphery in correspondence of the last ranks from the knitting needle (2) .

3. Device for drawing a knitted tubular manufacture, according to claim 2, wherein the said needles perforate approximately the last four or five ranks.

4. Device for drawing, according to claim 2, wherein the said crown (6) is placed at an end of an arm (1')/ the said arm being operable by a rack (4) and pinion (10) coupling.

5. Device for drawing a knitted tubular manufacture, according to claim 4, wherein the said arm (I' ) is shaped according to an approximate L shape, the said arm being hinged around the said rack (4) on the opposite side of the said crown (6), the said rack being placed in combination with the said pinion (10) in such a way that the operation of the pinion with respect to the rack allows the rotation of the said arm around the said rack.

6. Device for drawing a knitted tubular manufacture, according to one or more of the preceding claims, wherein an unhooking device (13) is comprised, operable according to an alternate up/down motion to allow the disjunction of the tubular from the hooks after the sewing.

7. Unit for the production of knitted tubular, as socks and similar, and comprising: - A cylindrical body (3) comprising a crown of needles (2) and sinkers (12) for the formation of the knitted tubular;

A device for the drawing (1) of the said knitted tubular manufacture comprising means of grasp (6, 11) comprising a supporting element (6) for a plurality of hooks (11) able to realize the grasp of the manufacture, the said device being configured in such a way as to be moved between a position external to the said cylindrical machine and a position coaxial to it in which the said hooks (11) result bound on the knitted tubular to draw it and vice-versa;

- A sewing machine (17) placed in correspondence of the said external position to allow the closure of the toe of the said tubular; and characterized by the fact that the said hooks (11) are fixed and configured in such a manner that, following the approach of the said drawing device towards the said tubular, the hooks penetrate the stitching realizing the grasp.

8. Method for the realization of a tubular knitted manufacture comprising the operations of:

Formation of a knitted tubular starting from the edge and finishing with the toe by means of a cylindrical tubular machine comprising in combination a cylinder of knitting needles (2) and sinkers (12) ;

Insertion of a drawing element (5) in the knitted tubular in formation and release of the needles from the said stitch in such a way as to allow the grasp of the tubular;

Removal of the said knitted tubular and transportation to a sewing section (17); - Closure of the toe with the said sewing machine

(17); characterized by the fact that the said operation of insertion of the drawing element comprises the approaching of a crown of fixed hooks (11) towards the tubular in such a way that the said hooks pierce the stitches by grasping them and allowing their subsequent removal from the cylindrical machine.

9. Method for the realization of a tubular knitted manufacture, according to claim 8, wherein the said approach comprises the operation of lowering of the said drawing element (5) on the said tubular in such a way that the said needles perforate the tubular in correspondence of approximately the fourth or fifth rank from the needle (2) that forms.

10. Method for the realization of a tubular knitted manufacture comprising the operations of:

- Arrangement of a drawing element (5) above the knitted tubular in formation;

Hooking of the formed tubular by means of hooking means of the fabric (11) of the manufacture arranged on the said drawing element; Removal of the said knitted tubular and transportation to a sewing section (17) ;

Closure of the toe with the said sewing machine (17); characterized by the fact that the said hooking operation of the tubular comprises the releasing operation of the needles (2) of the stitching in such a way that the elastic return effect of the toe of the said tubular projects the edge relative to the said toe against a crown of fixed hooks (11) placed above the said drawing element in such a way that the hooks pierce the stitching.