"Sewing Machine and Process for Sewing at least two superposed Flaps of Fabric to one another".

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The present invention relates to a sewing machine of the overlock cut and sew type for sewing two superposed fabric flaps together and belonging to one or more textile articles. The invention further relates to a process for sewing together at least two superposed flaps of fabric by means of a sewing machine of the overlock cut and sew type.

The sewing machine of the overlock cut and sew type can be, purely by way of example, a machine of a type produced by UNION SPECIAL ^® in one of the models of the 9M series or the like, as described for example in the relative instruction manual and catalogue code 103XQA-GR of November 2006. The type of stitch known as "overlock", and also as "overedge", is in itself widely known in the sector and will therefore not be further described in the present description. As is known, this type of sewing machine can be used for numerous applications, among which also the sewing of textile articles in light fabric such as ladies' stockings, tights and the like. These sewing machines are particularly applied as components of known machines for assembly of textile articles in automatic mode, in which the assembly of more than one textile article is performed automatically (for example, the assembly of two tubular stockings to form a textile article known as panty-hose).

In the field of these machines for assembly of textile articles the sewing machines of the overlock cut and sew type perform, completely automatically, the cutting and sewing of at least two flaps of fabric, by movement of suitable sewing needles and elements of known type known as crochets, with no intervention by an operator.

It is known that the type of sewing realised by the sewing machines of the overlock cut and sew type, in which two flaps of fabric are sewn superposed on one another, can in some cases exhibit an excessive thickness with regard to optimal use of the product, and thus can be aesthetically unappealing and uncomfortable in the final use of the product.

An example of the known type of sewing machine is found in US patent no. US3,079,882A (Washburn) which illustrates a machine of the overedge type with a specific needle plate and two sewing needles and the contents of which, relative to the description of the formation of sewing stitches, is to be taken as incorporated in the present text for purposes of reference. The two- stitch sewing realized by this machine enables effectively sewing the two flaps of fabric, but is excessively thick for some particular applications, for example the sewing of tights and in general light textiles, with respect to which the presence of the sewn seam in relief can be undesirable. A further example of sewing machine of the overedge type is illustrated in US patent US3,885,509A (Cox), which illustrates a machine provided with three sewing needles cooperating with a needle plate having two passage seatings for the needles, with a first needle passing in a respective seating, and the remaining two needles passing in a further and common seating. This solution has been proposed for attempting to obtain a less thick but equally effective sewn seam , but the result is only partially satisfactory.

A third solution that has been proposed and illustrated in US patent US6,167,825 (Marchetti), in which a sewing machine of the overlock type is equipped with two sewing needles and a needle plate having a lateral appendage having a first portion with substantially parallel sides and a second portion which narrows them. The contents of this patent, relative to the description of the structure of the knitting machine and the formation of the sewing stitches, should be considered as incorporated in the present text for purposes of reference. This solution was aimed at enabling an overlock type sewn seam to be obtained which subsequently can be more greatly stretched by separating the two flaps of sewn fabric, and thus a less thick seam. This solution is not without drawbacks, as the presence of the first parallel position can obstruct the running of the sewn stitches and as the conformation of the needle plate illustrated in the patent determines a not- very-narrow seam in the join point of the two flaps of fabric, with the risk, especially in the case of light textiles, of having an opening of the seam in certain stitches, with ensuing aesthetic and functional drawbacks.

The aim of the present invention is therefore to obviate one or more of the above-described drawbacks.

An aim of the invention is to disclose a sewing machine of the overlock cut and sew type which enables sewing at least two flaps of fabric together, the flaps being superposed on one another and belonging to one or more textile articles, realising textile articles of high quality and substantially free of imperfections.

A further aim of the invention is to provide a sewing machine of the overlock sew and cut type which enables reducing production waste.

A further aim of the invention is to provide a sewing machine of the overlock sew and cut type which enables obtaining stitches of high quality and perfectly "closed" at the joining point between two flaps of fabric.

A further aim of the invention is to provide a sewing machine of the overlock sew and cut type which enables increasing, in a fully controlled way, one or more sewing stitches realised by the sewing machines so as to enable a controlled and predetermined stretching of the stitches with respect to the remaining stitches. A further aim of the invention is to provide a sewing machine of the overlock sew and cut type which enables obtaining stitches which are extensible in a controlled way so as to provide a larger stitching effect and/or a flatter effect with respect to known stitches.

A further aim of the invention is to provide a sewing machine of the overlock sew and cut type which enables obtaining production with a high degree of uniformity among the various articles produced.

A further aim of the invention is to provide a sewing machine of the overlock sew and cut type which enables realising sewing simply, rapidly and automatically, in particular also when integrating the sewing machine in an automatic machine for assembling textile articles.

A further aim of the invention is to provide a sewing machine of the overlock sew and cut type which is simple, sturdy and economical to produce, including in terms of contained modifications with respect to sewing machines of known type.

These and other aims, which will be more fully explained in the course of the following description, are substantially attained by a sewing machine of the overlock cut and sew type, and by a process for use thereof, in accordance with the appended claims, in any combination among them and/or with one or more of the aspects indicated herein below.

According to further aspects of the invention, each of which can be taken alone or in combination with any one of the claims or the other aspects set down in the following, the invention can further relate to a sewing machine in which:

- the sewing machine further comprises stitch-increasing means able to determine a predefined lengthening of at least one or more stitches in production on the sewing machine;

- the stitch-increasing means comprise at least a spacer element arranged in proximity of and above the needle plate and such as to enable passage between the spacer element and the needle plate of the at least two superposed flaps of fabric to be sewn, the spacer element having at least a first stitch-increasing portion extending at least at a part of a first of the separating portions of the needle plate, such as to define a raised rest surface with respect to an upper rest surface of the needle plate such as to determine a predefined and controlled increase in size of at least a first stitch of the sewing stitches under production on the sewing machine;

- the stitch-increasing means comprise at least a lower crochet provided with an additional gripping portion for the sewing yarns;

- each of the seatings for sewing needle passage is dimensioned and configured for passage of a single and corresponding sewing needle;

- the seatings for sewing needle passage are entirely separated from one another over the whole length thereof by means of the separating portions and/or are defined by through-openings completely distinct from one another;

- the needles are mounted on the needle-bearing device with a reciprocal distance defined by an interaxis comprised between 14 and 2.8mm, or between 1.5 and 2.5mm or between 1.6 and 2.0mm and/or the needles are reciprocally equidistanced, being mounted on the needle-bearing device with identical distances between adjacent needles;

- at least a lateral appendage defining a running line and/or at least one of the separating portions and/or all the separating portions are inferiorly terminated or tapered for enabling the passage of the lower crochet in proximity of the needle plate;

- the running line of the lateral appendage exhibits, at least in a tract extending between the passage zone of the sewing needles and a front end portion of the appendage, or over a whole extension thereof, a conformation which is substantially straight and transversal with respect to a prevalent longitudinal development direction of the lateral appendage and/or to the running direction of the flaps of textile;

- the running line of the lateral appendage exhibits, at least in a section extending between the sewing needle passage zone and a terminal end of the appendage, or in all of the extension thereof, a conformation that is substantially curvilinear and transversal with respect to a prevalent longitudinal development direction of the lateral appendage and/or the running direction of the flaps of fabric and/or wherein the substantially curvilinear conformation is substantially concave or wherein the substantially curvilinear conformation is substantially convex;

- the lateral appendage exhibits a front portion having a narrowed end, having a thickness measured in a plane passing through an upper rest surface of the needle plate of less than 2 mm or 1 mm or 0.5mm, and a rear base portion, opposite the front end portion, having a thickness, transversal to its longitudinal extension, comprised between 4 mm and 7 mm, or between 5 mm and 6.5 mm, or between 5.5 and 6 mm

- the lateral appendage exhibits, at the passage zone of the sewing needles, a thickness transversal to its longitudinal extension that is comprised between 3 mm and 6 mm, or between 4 mm and 5.5 mm, or between 4.2 and 5 mm, or wherein said transversal thickness is greater than 3 mm, or greater than 3.5 mm, or greater than 4 mm, or greater than 4.2mm;

- four sewing needles mounted on the needle-bearing device are comprised and the needle plate is provided with four openings for passage of sewing needles;

- at least a third stitch-increasing portion is comprised of a spacer element and/or at least a third spacer element is comprised;

- the spacer element is realised in a single piece with the needle plate;

- the upper crochet is of a type supplied directly with the binding yarn, i.e. provided with at least an eyelet in which the sewing yarn passes and the lower crochet is "blind", i.e. it is without an eyelet supplied with the binding yarn and is provided only with a manipulating portion of the binding yarn;

- the lower crochet is fed directly with the binding yarn and the upper crochet is "blind";

- both the upper and lower crochets are of types directly fed with the binding yarn;

- at least one of the seatings for passage of sewing needles is dimensioned and configured so as to enable passage of two adjacent sewing needles;

- at least two separating portions are present, or wherein the separating portions each exhibit a thickness of at least 0.6mm or at least 0.8mm or at least 1 mm;

- the separating portions exhibit a longitudinal extension along an advancing direction of the flaps of fabric of at least 0.5 cm, or at least 1 cm, or at least 1.5 cm;

- the needle plate and/or a spacer element are made of a metal material;

- the openings defining the seatings are realised by milling of the needle plate;

- the separating portions are defined by separating elements mounted on the needle plate in corresponding mounting seatings;

- the yarn recall device of the binding yarn from the upper crochet and/or from the lower crochet is a stretcher blade oscillating in synchrony with the sewing needle-bearing device;

- the sewing machine is automatic and/or is integrated in a machine for assembling textile articles;

- the yarn feeder for needles and the binding yarn feeder are of an active type, able to actively supply the yarn to the needles or to the crochets;

- the needle yarn feeder and the binding yarn feeder are of a passive type and able to passively supply the yarn which is pulled directly by the needles or the crochets.

In a further aspect the invention further relates to a sewing device of the overlock cut and sew type, comprising at least a needle plate and at least two sewing needles, and according to the characteristics indicated in any one of the claims or the aspects indicated in the following.

In a further aspect the invention further relates to a machine for assembling textile articles comprising a sewing machine according to any one of the appended claims or aspects indicated in the following.

In a further aspect, the invention further relates to an equipment for a cut and sew sewing machine for sewing together at least two flaps of fabric, the flaps being superposed on one another and belonging to one or more textile articles, the equipment comprising at least: a needle plate for supporting at least two superposed flaps of fabric of one or more textile articles running for the formation of sewing stitches, at least a sewing needle-bearing device, provided with at least two sewing needles, and at least a spacer element and/or a lower crochet having characteristics as defined in the appended claims.

In a further aspect, taken alone or in combination with any one of the claims or aspects indicated in the following the invention further relates to a process further comprising the step of moving the spacer element with respect to the needle plate during the production of the sewing stitches. Further characteristics and advantages will more fully emerge from the detailed description that follows of a preferred but not exclusive embodiment, in according with the accompanying figures of the drawings, in which:

- figure 1 is a perspective view of some components of a sewing machine according to a first embodiment;

- figure 2 is a larger-scale view of a component of figure 1 , in particular of a needle- bearing device with the relative needles mounted;

- figure 3 is a larger-scale view of a further component of figure 1 , in particular a lower crochet;

- figure 4 is a detail of the sewing machine of figure 1 , relative to a formation step of the sewing stitches, with a needle plate sectioned for reasons of clarity;

- figure 5 is a front view in section of the needle plate of figure 4, illustrating the sewing stitches realised at the needle plate;

- figure 6 is a perspective view of some components of a sewing machine in accordance with a second realisation and in an operating position in which a needle-bearing device is raised with respect to a respective needle-plate;

- figure 7 is alike to figure 6 in a second operating position in which the needle-bearing device is lowered and the needles pass through respective seatings of the respective needle plate;

- figure 8 is a view from above of the components of figure 6;

- figure 8A is a detail of a variant of the plate of figure 8 with a spacer element represented only partially for greater clarity;

- figure 8B is a view alike to figure 5 but relating to the second embodiment of figure 6-8;

- figure 9 is a view from above of a step of formation of the sewing stitches on two flaps of fabric, at the needle plate in figures 4 and 5;

- figure 10 is a plan view of two flaps of textile sewn by means of a process according to the invention, in which the textiles have subsequently been partially separated by stretching the sewing stitches realised; - figure 11 is a lateral view of the two flaps of fabric of figure 9, sewn by means of a process according to the invention and partially separated by stretching the sewing stitches realized.

With reference to the figures, 1 denotes in its entirety a cut and sew overlock sewing machine for sewing together at least two flaps 3a, 3b of superposed fabric belonging to one or more textile articles.

Figure 1 illustrates some essential components of the sewing machine 1 according to a first embodiment of the invention. The remaining parts of the sewing machine 1 are of a known type, and are not therefore illustrated in the appended figures and are not described in detail in the present description.

The sewing machine 1 comprises at least a needle plate 2 able to support at least two flaps 3a, 3b of fabric superposed on one or more running textile articles for formation of sewing stitches. The needle plate 2 is provided with through-openings defining respective seatings 4 for the passage of sewing needles 5 and at least a lateral appendage 6 defining a running line 7 for the sewing.

The needle plate 2 is provided with at least two, in the illustrated embodiment three, of the seatings 4 for passage of said sewing needles 5, each of said seatings 4 for the passage of sewing needles 5 being configured such as to be crossed by at least a respective sewing needle. The needle plate is provided with respective separating portions 8 able to at least partly separate each seating for passage of sewing needles 5 from the adjacent seatings at the needle 5 passage zone 9, in order to enable formation in parallel of at least two, and in the illustrated embodiment three sewing stitches 10a, 10b, 10c that are distinct and reciprocally distanced from one another.

Each of the seatings 4 for passage of sewing needles 5 can be dimensioned and configured for passage of a single and corresponding sewing needle, as in the embodiment illustrated in the accompanying figures.

The seatings 4 for passage of sewing needles 5 can be entirely separated from one another over a whole extension thereof by means of the separating portions 8. The seatings 4 for passage of sewing needles 5 can be defined by through-openings completely distinct from one another. The needle plate 2 can comprise at least two separating portions 8. The separating portions 8 can each exhibit a thickness for example of at least 0.6mm or at least 0.8mm or at least 1 mm. The separating portions 8 can exhibit a longitudinal extension along an advancing direction of the flaps 3a, 3b of fabric for example of at least 0.5 cm, or at least 1 cm, or at least 1.5 cm. The needle plate 2 can be made of a metal material and the openings defining the seatings 4 can be made by milling cuts in the needle plate 2. Alternatively, for example, the separating portions 8 can be defined by separating elements mounted on the needle plate 2 at corresponding mounting seatings.

In a further embodiment which is not illustrated, at least one of the seatings 4 for passage of sewing needles 5 can be dimensioned and configured so as to enable passage of two adjacent sewing needles 5, and therefore four through-needles 5 can be provided, for example, in three seatings 4, or three through-needles 5 in two seatings 4, two needles 5 being through-needles in a common seating.

The sewing machine 1 further comprises at least a sewing needle bearing device 11 , such as for example a needle-bearing bar.

The sewing machine 1 comprises at least two, and in the illustrated embodiment at least three sewing needles 5, mounted on the sewing needle-bearing device 11 reciprocally flanked, aligned with one another and fed with respective yarns 10 for needles. The sewing needles 5 are able to pass through the seatings 4 of the needle plate 2 so as to sew the flanks 3a, 3b of superposed fabric. The needles 5 can be mounted on the needle-bearing device 11 at a reciprocal distance defined by an interaxis comprised for example between 1.4 and 2.8mm, or between 1.5 and 2.5mm or between 1.6 and 2.0mm, corresponding to the distances between the eyelets 19 of the needles 5 from which the respective sewing yarns exit.

The needles 5 can be equi-distanced from one another, being mounted on the needle-bearing device 11 at identical distances between adjacent needles 5. In a variant that is not illustrated, the needles can be mounted with interaxes that are different from one another.

The needles can have the same caliber and be fed with identical yarns, or with different yarns of the same size. Alternatively the needles can exhibit different calibres and be fed with yarns of different size.

As visible for example in figures 1, 8A and 9, the running line 7 of the lateral appendage 6 can exhibit, at least in a section extending between the needle passage zone 9 of the sewing needles 5 and a front end portion of the appendage 6, or in its whole extension, a substantially straight conformation that is transversal with respect to a prevalent longitudinal development direction of the lateral appendage 6 and/or the running direction of the flaps 3a, 3b of fabric.

The lateral appendage 6 can exhibit a front portion 6a having a narrowed end having a thickness measured in a plane passing through an upper rest surface of the needle plate 2, for example of less than 2 mm or 1 mm or 0.5mm.

The lateral appendage 6 can exhibit a rear portion 6b of base, opposite the front end portion, having a thickness transversal to the longitudinal extension thereof comprised for example between 4 mm and 7 mm, or between 5 mm and 6.5 mm, or between 5.5 and 6 mm.

The lateral appendage 6 can exhibit, at the passage zone 9 of the sewing needles 5, a thickness 6c transversal to the longitudinal extension thereof comprised for example between 3 mm and 6 mm, or between 4 mm and 5.5 mm, or between 4.2 and 5 mm.

The transversal thickness can be for example greater than 3 mm, or greater than 3.5mm, or greater than 4 mm, or greater than 4.2mm. Alternatively, as visible in figures 6, 7 and 8 the running line 7 of the lateral appendage 6 can exhibit, at least in a section extending between the passage zone 9 of the sewing needles 5 and a terminal end of the appendage 6, or over a whole length thereof, a substantially curvilinear and transversal conformation with respect to a prevalent longitudinal direction of the lateral appendage 6 and/or the running direction of the flaps 3a, 3b of fabric. The substantially curvilinear conformation can be substantially concave, as illustrated, or substantially convex.

As visible in figures 5 and 8B, at least the lateral appendage 6 defining a running line 7 and/or at least one of the separating portions 8 and/or all the separating portions 8 can be inferiorly terminated or tapered so as to enable passage of a lower crochet in proximity of the needle plate 2.

The sewing machine 1 can further comprise an advancing device (not illustrated as of a known type and conventional) able to advance the flaps 3a, 3b of superposed fabric along an advancing direction with respect to the needle plate 2 during a sewing operation.

The sewing machine 1 can further comprise a device 12 for cutting the flaps 3a, 3b of superposed fabric at a fabric cutting line 20, in proximity and upstream of the lateral appendage 6 along said advancing direction of the flaps 3a, 3b of fabric, as illustrated in figure 7.

The sewing machine 1 can further comprise at least a sewing yarn feeder 13 for needles, able to supply sewing yarn to the needles 5 of the sewing machine.

The sewing machine 1 further comprises at least a lower crochet 14 and at least an upper crochet 15, able to contribute to forming sewing stitches 10a, 10b, 10c.

The sewing machine 1 further comprises at least a binding yarn feeder 16, able to supply binding yarn 17 to at least one of the upper crochet 15 and the lower crochet 14.

In the embodiment illustrated in the figures, the lower crochet 14 is supplied directly with the binding yarn 17 which passes in at least a relative eyelet, or two eyelets, and the upper crochet

15 is not supplied directly with the binding yarn 17 and is thus "blind".

In an embodiment that is not illustrated, the upper crochet 15 can be of a type fed directly with the binding yarn 17 and the lower crochet 14 can be of the blind type.

In greater detail, in the illustrated embodiment, the lower crochet 14, fed with binding yarn 17, contributes to the formation of the sewing stitches 10a, 10b, 10c by means of the relative binding yarn 17 which cooperates with the sewing yarn 10, while the upper crochet 15, not fed, or "blind", contributes to the formation of the sewing stitches 10a, 10b, 10c by operating on the binding yarn 17 fed by the lower crochet 14.

In the first embodiment illustrated in figures 1 , 3, 4, 5 and 9, the lower crochet 14 is provided with an additional gripping portion 25 for the sewing yarn 10, suitable for interacting, in a lower position to the needle plate 2, with at least a sewing yarn 10 destined to form at least a first sewing stitch 10c of said sewing stitches 10a, 10b, 10c such as to determine a predefined enlargement of said first sewing stitch 10c under production on said sewing machine.

The additional gripping portion 25 is able to interact with the sewing yarn 10 so as to pull the sewing yarn 10 and increase the quantity of sewing yarn 10 used for realising the sewing stitch 10c or the sewing stitches 10a, 10b, 10c.

The additional gripping portion 25 might be able to cooperate with at least two, or at least three sewing yarns 10 destined to form respective at least two, or at least three sewing stitches 10b, 10c such as to determine a predefined enlargement of the at least two, or at least three sewing stitches 10b, 10c under production on the sewing machine.

The additional gripping portion 25 for the sewing yarn 10 can be constituted by a protuberance, for example rounded, arranged in an intermediate portion between two end portions of the lower crochet 14.

The additional gripping portion 25 can extend from the lower crochet 14 transversally with respect to a main longitudinal extension direction of the intermediate portion.

The additional gripping portion 25 can be for example made in a single piece with the respective lower crochet 14.

The additional gripping portion 25 exhibits an extension, a conformation and a position on the crochet able to determine the desired cooperation with the sewing yarn, as illustrated in figure 4. The additional gripping portion 25 can be positioned on the lower crochet 14 at a distance from the front working end of the lower crochet 14 suitably determined in consideration of the conformation of the various elements involved and the desired pulling effect on the sewing yarns. The sewing machine 1 further comprises a recall device (not illustrated as of known type) of the binding yarn from the upper crochet 15 of the binding yarn 17 and/or from the lower crochet 14. The recall device of the binding yarn 17 from the upper crochet 15 and/or from the lower crochet 14 can be for example a stretcher blade oscillating in synchrony with the sewing needle bearing device 11. The yarn feeder 13 for needles 5 and the binding yarn feeder 16 can be of the active type, able to actively supply the yarn to the needles 5 or to the crochets, or alternatively the needle yarn feeder 13 and the binding yarn feeder 16 can be of the passive type and able to passively supply the yarn which is pulled directly by the needles 5 or by the crochets.

In a variant embodiment, not illustrated, the sewing machine 1 can comprise four of the sewing needles 5 mounted on the needle-bearing device 11 and the needle plate 2 can be provided with four of the openings for the passage of sewing needles 5.

In accordance with a second embodiment of the invention, illustrated in figures 6, 7, 8, 8A and 8B, the sewing machine further comprises at least a spacer element 21 operatively coupled to the needle plate 2 and having at least a first stitch-increasing portion 22 extending at least at a part of a first of the separating portions 8, such as to define a raised rest surface with respect to an upper rest surface of the needle plate 2 such as to determine a predefined and controlled increase in size of at least a first stitch 10c of the sewing stitches 10a, 10b, 10c under production on the sewing machine.

The spacer element 21 can be further provided with at least a second stitch-extending portion 23 developing at least at a part of a second of the separating portions 8, such as to define a raised rest surface with respect to the rest surface of the needle plate 2 and determine a predefined increasing of at least a second stitch 10b of the stitches 10a, 10b, 10c produced by the sewing machine. The spacer element 21 is arranged in proximity of and above the needle plate 2 and in such a way as to enable passage between the spacer element 21 and the needle plate 2 of the two superposed flaps 3a, 3b of fabric.

The spacer element 21 can be movably mounted so as to enable varying the height position with respect to the needle plate 2 and enable passage of the flaps 3a, 3b of superposed fabric. For example, the spacer element 21 can be operatively connected or mounted to a fabric feed- presser device 18 (of known type and therefore not described in greater detail) able to compress and maintain in position at the at least two superposed flaps 3a, 3b of fabric during the sewing. The sewing machine can further comprise at least an additional spacer element provided with at least an additional stitch-extending portion at least a part of a second of the separating portions 8, so as to define a raised rest surface with respect to a rest surface of the needle plate 2 to determine a predefined extending of at least a second stitch 10b of the stitches 10a, 10b, 10c produced.

In accordance with the invention the spacer element and/or the stitch-increasing portion 22 extend at least at part of a first and/or a second of the separating portions 8 and are configured such that the rest surface is able to support, in a raised position with respect to the upper rest surface of the needle plate 2, at least a stitch produced previously to the first stitch and/or the second stitch 10, 10c in production on the sewing machine (i.e. at least a respective stitch previously produced for each between the first and the second stitch), or at least two sewing stitches produced previously to the first stitch and/or the second stitch 10, 10c in production on the sewing machine or at least three stitches produced previously to the first stitch and/or the second stitch 10b, 10c in production on the sewing machine.

For example, the stitch-increasing portion 22 can extend at least over 20% or at least 30%, or at least 40% or at least 50% or at least 60% or at least 70% of the extension of a first of the separating portions 8.

The above-described characteristics enable maintaining the sewing stitches extended also after the formation thereof, thus up to at least one or two or three preceding stitches before the ones under production, so as to enable a dimensional consolidation thereof and preventing the tensions of the yarn from annulling the extension obtained, thus reducing the dimensions of the stitches already produced.

The spacer element 21 can be mounted adjustably via mounting or fine-adjusting means 24 so as to enable varying the position with respect to the needle plate 2 in at least a parallel direction to an upper rest surface of the needle plate 2 or in at least two distinct directions parallel to the upper rest surface of the needle plate 2 and perpendicular to one another.

The spacer element 21 can further be selectively fixable, at least with respect to a displacement in a parallel plane to the upper surface of the needle plate 2, in at least an operating position during the functioning of the sewing machine for the production of stitches 10a, 10b, 10c.

In an alternative embodiment, the spacer element 21 can be movably mounted so as to enable varying the position thereof with respect to the needle plate 2 in at least a parallel direction to an upper rest surface of the needle plate 2 or in at least two distinct directions parallel to the upper rest surface of the needle plate 2 and reciprocally perpendicular, during the functioning of the sewing machine for the production of the stitches 10a, 10b, 10c. In this case the sewing machine can comprise activating means for moving the spacer element 21 in a predetermined way during the functioning of the sewing machine for the production of the stitches 10a, 10b, 10c.

The raised rest surface of the first stitch-increasing portion 22 and/or the second stitch-increasing portion 23 can be inclined and transversal with respect to the rest surface of the needle plate 2 and/or with respect to the prevalent longitudinal development direction of the respective stitch- increasing surface of the respective stitch-increasing portion and/or with respect to the running direction of the flaps 3a, 3b of fabric.

The first 22 and/or the second stitch-increasing portion 23 can exhibit a thickness which narrows progressively along the prevalent longitudinal development direction of the respective separating portion 8, the height of the raised rest surface being minimal at the respective terminal ends of the first and/or the second stitch-increasing portion 23.

The first 22 and/or the second stitch-increasing portion 23 can exhibit a thickness which progressively tapers in a perpendicular direction to the prevalent longitudinal development direction of the respective separating portions 8, the height of the raised rest surface being decreasing in the direction of and towards the lateral appendage 6 of the needle plate 2.

At least a part of the spacer element 21 and/or the respective stitch-increasing portions can be operatively arranged and/or mounted above the needle plate. In an alternative embodiment at least a third stitch-increasing portion of the spacer element 21 can be included, or at least a third spacer element can be included. In a variant, the spacer element 21 can be realized in a single piece with the needle plate.

In a third embodiment, the invention comprises both the elements illustrated and described with reference to the first embodiment and the elements of the second embodiment, determining a selective and controlled increasing of the sewn stitches deriving from the conjoined effect of the spacer element 21 and the additional gripping portion 25.

The invention further relates to a spacer element 21 for a sewing machine 1 of the overlock cut and sew type, couplable at a respective needle plate 2 of the sewing machine 1 and having one or more of the characteristics described previously in any combination.

The invention further relates to an equipment for a sewing machine 1 of the overlock cut and sew type, the equipment comprising at least a needle plate 2 and at least three sewing needles 5, so as to enable formation of at least three distinct stitches 10a, 10b, 10c reciprocally distanced from one another, as above described.

The equipment can essentially comprise at least the components illustrated in figure 1 and/or in figure 6. The sewing machine can be automatic, in particular in the case in which it is integrated in a machine for assembling textile articles.

The invention further relates to a machine for assembling textile articles, of known type and therefore not described in the present description, comprising a sewing machine 2 of the above- described type. The sewing machine will not be described in greater detail as the remaining parts thereof are conventional and of well-known type.

The present invention further relates to a process for sewing together at least two flaps 3a, 3b of superposed fabric by means of a sewing machine of the overlock cut and sew type.

In a first embodiment the process comprises at least steps of: regulating the position of a spacer element 21 with respect to a needle plate 2 so as to define a desired increase over at least one or at least two stitches 10, 10b, 10c to be produced; arranging at least two superposed flaps 3a, 3b of fabric at a needle plate 2 of a cut-and-sew "overlock" sewing machine 1 , the needle plate 2 being provided with at least two or at least three openings, at least partly distinct from one another, for the passage of sewing needles 5; advancing said flaps 3a, 3b of fabric with respect to said needle plate 2; progressively cutting a lateral portion of said flaps 3a, 3b of fabric; passing through each of said openings for the sewing needle passage 5 with at least a respective sewing needle fed with a respective sewing yarn 10 such that the at least three reciprocally-flanked sewing needles 5 sew said flaps 3a, 3b of fabric to one another, realising at least three distinct sewing stitches 10a, 10b, 10c, cooperating with at least a lower crochet 14 and with at least an upper crochet 15, at least one of the crochets being fed with a binding year 17.

In the second embodiment, the process further comprises a step of manipulating, during the production of the distinct stitches 10a, 10b, 10c at least one 10c of the stitches or at least two 10b, 10c of the stitches, or all the stitches 10a, 10b, 10c by means of an additional gripping portion 25 of the lower crochet 14 so as to determine a predefined increase of the respective sewing stitches 10a, 10b, 10c under production on the sewing machine and manipulated by the additional gripping portion 25.

Various aspects of the process, corresponding to the further aspects described above in relation to the sewing machine, are not repeated here.

The further aspects of the formation process of the sewing stitches not described in detail in the present description and not deriving from peculiar characteristics of the sewing machine as described above, are to be considered of known type.

The invention as it is conceived is susceptible to numerous modifications and variants, all falling within the scope of the inventive concept, and the cited components are replaceable with other technically equivalent elements.

The invention offers considerable advantages.

Primarily the invention enables obviating at least some of the drawbacks of the prior art. The invention further sews at least two superposed flaps of fabrics together, the flaps belonging to one or more textile articles, realizing textile articles of high quality and substantially free of imperfections.

The invention further enables obtaining sewn seams of high quality and "closed" perfectly at the join point between two flaps of fabric and/or reducing production waste.

The invention further enables obtaining sewn seams which are extensible in a controlled way so as to provide a wider and/or flatter sewing effect with respect to known seams.

The invention further enables selectively widening and/or softening with high precision and repeatability one of the stitches produced with respect to the other stitches.

The invention further enables obtaining production of high uniformity among the various produced articles. The invention further enables realizing seams in a way that is simple, rapid and automatic, in particular also integrating the sewing machine in an automatic machine for assembly of textile articles of known type.

The invention is further simple, sturdy and economical to produce, and guarantees high standards of repeatability and safety.