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The present invention relates to an improved sewing machine .

The sewing machine according to the present invention allows seams on any textile support, according to established schemes and models.

Multi-needle sewing machines are known as described in U.S. patent no. US 8,250,997, equipped with at least one horizontal shaft in oscillating rotation, to which, individually and selectively, a series of needle sewing devices are coupled by means of corresponding connection/disconnection mechanisms.

Each needle sewing device is formed by two parts, reciprocally coupled in an articulated and removable way, of which a first part is integral with the shaft and a second part, on which the needle is installed, it is enabled to move in vertical alternative motion.

Each connection/disconnection mechanism provides a slidable engagement, operating so as to be able to selectively engage and keep separate the aforesaid second part of the corresponding needle sewing device from the respective second part, so as to make mutually independent shaft and needle.

However, known sewing machines, described above, have several disadvantages and drawbacks, such as the structural complexity of the means for actuating the shaft and the low reliability of operation, together with the need of frequent maintenance .

In light of the above, it is, therefore, object of the present invention to provide a sewing machine that is reliable in use and simple to use.

Another object of the invention is to provide a sewing machine that has a reduced structural complexity.

Further object of the present invention is to provide a sewing machine that is economical and which does not require substantial and frequent maintenance.

It is therefore specific object of the present invention a sewing machine for sewing textile products, comprising: a frame, a shaft, rotatably engaged with said frame about a rotating axis and rotating in only one direction about said rotating axis, motor means, connected with said shaft to make said shaft rotate in only one direction about said rotating axis, at least one sewing device comprising a needle, connecting means, for selectively connecting said needle with said shaft, wherein which connecting means may be configured in at least two configurations, namely a first neutral configuration, wherein said needle and said shaft are mutually disconnected and a second operative configuration, wherein said needle and said shaft are mutually connected; wherein said needle is substantially motionless and said shaft rotates in said first neutral configuration, and said needle moves with an alternate translational motion and said shaft rotates in said second operative configuration, at least one crochet device, configured to co-operate with a respective sewing device, to perform at least one seam in a textile product.

Still according to the invention, said connecting means could comprise at least one eccentric mounted on said shaft.

Preferably according to the invention, said connecting means could comprise a lever wherein at least one opening is formed wherein said at least one 4000188 eccentric is arranged, said opening being formed by a first small portion and a second enlarged portion, which mutually communicate.

Further according to the invention, said connecting means could comprise at least one sliding bush mounted on said at least one eccentric .

Advantageously according to the invention, said connecting means could comprise actuating means for moving said lever between a first operative position, wherein said at least one eccentric is arranged in said first small portion of said opening and causes the lever to oscillate and the needle to alternately translate by rotating about said rotating axis, and a second neutral position, wherein said at least one eccentric is arranged in said second enlarged portion of said opening and does not interfere with said lever by rotating about said rotating axis.

Still according to the invention, said connecting means could comprise a holder to hold said needle and a connecting member articulated to said lever and said holder .

Preferably according to the invention, said actuating means could comprise a piston-cylinder pneumatic system.

Further according to the invention, said lever could comprises a positioning element and in said frame a guide opening could be formed, such that said positioning element is arranged outside said guide opening when said lever is in said first operative position, and such that said positioning element is arranged in said guide opening when said lever is in said second neutral position.

Advantageously according to the invention, said sewing machine could comprise guide means for guiding said needle with an alternate translational motion.

The present invention will be now described, for illustrative but not limitative purposes, according to its preferred embodiments, with particular reference to the figures of the enclosed drawings, wherein:

figure 1 shows a sewing machine according to the present invention, as a whole,- figure 2 is a detail view of a part of the sewing machine shown in figure 1;

figure 3 is a side view of a sewing device of the sewing machine of figure 1, in an operating configuration; and

figure 4 is a side view of the sewing device of figure 3, in a neutral rest configuration.

In the various figures, similar parts will be indicated by the same reference numbers .

Referring to figures enclosed, 1 denotes a sewing machine comprising a frame 2 formed so as to present an opening 3 for the passage of a textile product to be processed 4.

The textile product 4 is moved forward and passes through said opening 3, through the action operated by a rotating roller 2' arranged in correspondence of said opening 3.

A needle operating unit 5 is arranged in said opening 3 comprising a rotating shaft 6 arranged substantially horizontal and rotatably constrained to the frame 2.

Said shaft 6 is connected to motor means (not shown in the figures) adapted to set it rotating, in one direction only (as indicated by arrow 8) , around its symmetry axis 7. On the shaft 6 is mounted a plurality of cams 9, each formed by a roller mounted eccentrically on said shaft 6.

On the roller of each eccentric 9 a sliding bus 9' is also mounted.

Moreover, the needle operating unit 5 comprises a plurality of sewing devices 10 mounted on said shaft 6.

Each sewing device 10 comprises a slide 11, movable in a direction perpendicular with respect to the symmetry axis 7 of the shaft 6 and driven by a pneumatic piston-cylinder 12.

In particular, said slide 11 is movable between a neutral position (shown in figure 4) , in which the piston of said pneumatic piston-cylinder assembly 12 is in retracted configuration, and an operating position (shown in figure 3) , in which the piston of said pneumatic piston-cylinder system 12 is in elongated configuration .

On said slide 11 a shaped lever 13 is hinged, oscillating about an oscillation axis 13' parallel to the symmetry and rotation axis 7 of the shaft 6.

An opening 14 is obtained on the lever 13, on which one of said plurality of eccentric 9 is arranged.

Said opening 14 is formed by a first narrow portion 14a, and a second enlarged portion 14b, communicating with each other, in which said first portion 14a is located closer to the oscillation axis 13' with respect to said second portion 14b.

In particular, said first narrow portion 14a has a profile comprising two sections 14a' , 14a" , substantially rectilinear and parallel to each other, arranged so as to link with the profile of the said second portion 14b. The second portion 14b of the opening 14 has, instead, a shape such that the outer circumference described by the rotary movement of the eccentric 9 around the rotation axis 7 is completely contained in said second portion 14b, so that, when said eccentric 9 is set in rotation by said shaft 6, it does not interfere with the lever 13.

On the upper part of the lever 13 a positioning roller 15 is provided, intended to be inserted, when said slide 11 is in neutral position, in a guide opening 16 obtained in a support arm 17 fixed to the frame 2.

Said guide opening 16 extends in a direction substantially parallel to the mobility direction of the slide 11 and is shaped so as to present an invitation 16' , suitable to facilitate the entrance of the positioning roller 15 in said guide opening 16.

Each sewing device 10 also comprises a rigid connection member 18, hinged, in correspondence of the respective ends and according to respective rotation axes substantially parallel to the oscillation axis 13', to an end portion of said lever 13, which is opposite to the relative area affected by said oscillation axis 13', and to a holder rod 19 bearing, at its lower end, a needle 20 by a clamp 21.

Said holder rod 19 is constrained to move vertically, due to the guiding function carried out by a guide member 22 fixed to the frame 2.

Said guide member 22 has two protruding portions 22a, 22b, in which two coaxial holes are obtained.

Within of said two coaxial holes two sliding bushes 23a, 23b are respectively housed, through which said holder rod 19 passes and moves. The sewing machine 1 also comprises a crochet operating unit (not shown in the figures) , arranged under the needle operating unit 5 and comprising a plurality of crochet devices positioned mutually side by side, each arranged in correspondence of one respective sewing device 10.

The operation of the sewing machine 1 described above is as follows.

Taking now into account a single sewing device 10, when the respective slide 11 is in neutral position, as shown in figure 4, the lever 13 is arranged in such a way that the positioning roller 15 is inserted into the guide opening 16 and the corresponding eccentric 9 is, instead, arranged in the second portion 14b of the opening 14.

In this case, therefore, although the shaft 6 rotates together with the respective eccentrics 9, the lever 13, as well as the other members connected to it, indicated above, remains still.

Therefore, in this configuration also needle 20 remains stationary in a respective raised position, thus not interfering with the underlying textile product 4.

When instead the slide 11 is in operating position, as shown in figure 3, the lever 13 is positioned in such a way that the positioning roller 15 is out of the guide opening 16 and the corresponding eccentric 9 is arranged in the first portion 14a of the opening 14.

In the latter case, the eccentric 9, rotating around the symmetry axis 7 of the shaft 6 and contacting, in its rotational movement, the aforesaid sections 14a' , 14a" of the profile of said first portion 14a, causes the rotary and oscillatory motion of the lever 13 and, consequently, the vertical reciprocating movement of the holder rod 19 and of the needle 20 connected to it.

A wire is naturally connected to the needle 20 of each sewing device 10 active, i.e. with the slide 11 in the operating position, said wire being used by the active sewing device 10 and by the crochet device below to carry out a seam in the textile product 4.

Therefore, by suitably varying the configuration of the active seam devices 10 and of inactive ones, i.e. still, in the needle operating unit 5, it is possible to realize seams in different areas of the textile product 4, while it passes through the opening 3 of the sewing machine 1.

The present invention has been described for illustrative but not limitative purposes, according to its preferred embodiments, but it is to be understood that modifications and/or changes can be introduced by those skilled in the art without departing from the relevant scope as defined in the enclosed claims.