WO2018185603A1

WO2018185603A1 - A shrinking machine

Info

Publication number: WO2018185603A1
Application number: PCT/IB2018/052048
Authority: WO
Inventors: Davide MANZARDO
Original assignee: Red Carpet S.R.L.
Priority date: 2017-04-07
Filing date: 2018-03-26
Publication date: 2018-10-11
Also published as: CN110546320A; EP3607132A1; IT201700038499A1; CN110546320B; EP3607132B1

Abstract

A shrinking machine for fabrics (T) comprising: a flexible belt (2) for supporting and transporting a fabric (T), the flexible belt (2) being arranged in a closed loop around an inlet roller (4) and an outlet roller (5); an intermediate body (7) of which a stretch (9) of the outer surface (8) identifies with a corresponding stretch (10) of the flexible belt (2) between the two rollers (4, 5) a sliding channel (11) for the fabric (T); a metal mesh (18) arranged in contact with the flexible belt (2) starting from a point corresponding to the inlet roller (4) and terminating at a point coinciding with or following the inlet point (19) of the sliding channel (11).

Description

A SHRINKING MACHINE

D E S C R I P T I O N

Field of application

The present invention is applicable to the textile field and, in particular, relates to a shrinking machine for fabrics.

More in detail, the present invention relates to the shrinking portion of a shrinking machine.

State of the art

During the processing process, a fabric is subjected to a certain tension, which causes its temporary elongation. The need therefore arises to eliminate the aforesaid elongation in order to prevent the fabric from spontaneously recovering it during or after the packaging of the final product. In fact, this aspect irremediably compromises the quality of the product itself.

To this end, machines for fabric shrinking are known to induce recovery of elongation and stabilize the fabric after processing.

A type of such shrinking machines comprises a flexible felt belt arranged in a closed loop around a series of rollers which manage, among other things, its movement.

In particular, there are an inlet roller and an outlet roller, arranged in contact with the inner side of the loop, and an intermediate cylinder interposed between the aforementioned rollers and of considerably greater diameter than these, arranged in contact with the outer side of the loop so as to create a concavity in the latter.

The fabric to be treated is made to pass between the belt and the intermediate cylinder. There is also a flexible sheet, generally of Teflon-coated glass fibre, called "shoe", arranged between the inlet roller and the intermediate cylinder so as to keep the fabric in contact with the belt on a trajectory stretch that develops from the inlet roller to the intermediate cylinder.

The sheet is locked at one end thereof corresponding to the inlet roller, while the other end is allowed to continue between the flexible belt and the intermediate cylinder. The rotation of the latter and the simultaneous sliding of the flexible belt determine a limited tension of the sheet which is between them.

The aforesaid flexible sheet has the advantage of easily adapting to variations in thickness of the fabric, such as those at the seams, while maintaining the fabric adhering to the belt.

The inlet roller, the intermediate cylinder and the flexible sheet define a trajectory for the fabric which comprises a first stretch with a concavity facing the inlet roller and an immediately following stretch with a concavity facing the intermediate cylinder, i.e. opposed to that of the previous stretch. Advancing along the aforementioned trajectory, the fabric is kept in contact with the surface of the felt belt by the shoe and undergoes the same surface deformations of the latter.

More precisely, during the passage between the inlet roller and the intermediate cylinder, the felt belt reverses its curvature so as to shrink its outer surface. The aforementioned compression is transmitted to the fabric and causes its shrinking.

However, it is observed that the greater the difference in speed between the convex trajectory stretch around the inlet roller and the concave stretch around the intermediate cylinder, the greater the shrinking potential of the machine.

In this sense, in order to try to increase the shrinking effect of the fabric, an attempt has been made to reduce the diameter of the return roller to a minimum and increase the thickness of the flexible belt since, in this last case, increasing the shrinking forced exerted by the same. However, it is not possible to overcome certain physical limits, because the inlet roller, if too small, tends to flex, ruining the quality of the fabric and risking compromising the same machine. Moreover, in the case of the flexible belt, it is not possible to excessively increase the thickness as it tends to break when subjected to traction and subsequent compression.

There are, however, some types of fabric that fail to adhere correctly to the felt belt, thereby generating a "shrinking rejection" effect which manifests itself in folds on the fabric coming out of the machine.

With regard to the sheet, then, being a stationary element and comprised between two rotating elements such as the flexible belt and the heated metal drum, it is subjected to rubbing which tends to deteriorate it over time. This in itself constitutes a problem because it forces frequent machine downtimes for maintenance work to replace the sheet. As a consequence, not only maintenance costs, but also production costs increase, due to machine downtime.

Presentation of the invention

The object of the present invention is to overcome at least partially the drawbacks highlighted above by providing a shrinking machine which requires less maintenance interventions compared to known equivalent machines.

More in detail, an object of the invention is to provide a shrinking machine in which the sheet is less subject to wear than known equivalent shrinking machines.

A further object is that the shrinking machine of the invention allows the correct processing also of difficult fabrics which, in the known machines, tend to refuse shrinking.

Said objects, as well as others which will become clearer below, are achieved by a shrinking machine according to the following claims, which are to be considered as an integral part of this patent.

In particular, the machine comprises at least one flexible belt for supporting and transporting the fabric. This belt is arranged in a closed loop around at least one inlet roller and at least one outlet roller. There is also at least one intermediate body located near the flexible belt between the two inlet and outlet rollers. In this sense, a portion of the outer surface of the intermediate body identifies with a corresponding stretch of the flexible belt a sliding channel for the fabric.

The flexible belt, therefore, during its sliding around the inlet roller, sees at least its outer surface extend. In this situation, it receives the fabric, supporting it. Subsequently, the same flexible belt is subjected to a lower curvature, if not null or inverted, as in the case of the drawings. The result is a compression of the same outer surface of the flexible belt which causes a shrinking of the fabric. The latter, therefore, is shrunk. The aforementioned sliding channel allows first of all to keep the fabric arranged in contact with the flexible belt during its shrinking. Furthermore, since the intermediate body is typically heated, in the channel there is a heat transfer to the tissue in order to stabilize its shrinking. In other words, the shrunk fabric is ironed in the channel.

According to an aspect of the invention, the machine also comprises at least one metal mesh arranged in contact with the flexible belt starting from at least one point corresponding to the inlet roller and terminating at a point coinciding with or next to the channel inlet point.

In other words, instead of the sheet used in known equivalent shrinking machines, the machine of the invention uses a metal mesh.

Advantageously, therefore, this solution allows to reduce the maintenance interventions on the machine thanks to the use of the metal mesh. It is, in fact, more resistant than known sheets and this makes it less subject to wear.

Moreover, the mesh, although metallic, still has a particularly flexible structure and therefore allows to easily replace the sheet without any negative effects on the machine.

Moreover, as will be seen below, it can be tensioned without negative effects on its degradation, thereby allowing advantageously to increase the force exerted on the fabric to make it adhere as much as possible to the flexible belt. Advantageously, as a consequence the degree of shrinking of the fabric obtained by the machine of the invention with respect to the known equivalent machines is optimized.

According to a further aspect of the invention, the outer surface stretch of the intermediate body in correspondence with the conveying channel is convex and arranged in contact with the flexible belt. As a consequence, the corresponding stretch of the latter assumes a concave conformation and thus also the sliding channel. In other words, the flexible belt is subjected not only to a decrease in its curvature, but rather to a bending inversion.

Advantageously, this makes it possible to further increase the shrinking effect of the fabric.

Brief description of the drawings Further features and advantages of the invention will become more evident in light of the detailed description of a preferred but not exclusive embodiment of a shrinking machine according to the invention, illustrated by way of non-limiting example with the aid of the accompanying drawings, wherein:

FIG. 1 represents a shrinking machine according to the invention in schematic view;

FIG. 2 represents a detail of the shrinking machine of FIG. 1 . Detailed description of some preferred embodiment examples With reference to the mentioned figures and, in particular, to Figs. 1 and 2, described herein is a shrinking machine 1 for fabrics T.

It comprises a flexible belt 2 with which the fabric T to be shrunk is arranged in contact. Said belt 2 is arranged in a closed loop around some rollers 3 among which an inlet roller 4 and an outlet roller 5 are identified. The first corresponds to the point from which the fabric T is arranged in contact with the flexible belt 2, while the second identifies the maximum point of the path of the fabric T on the same belt 2. By reaching the outlet roller 5, the fabric T is taken from the flexible belt 2 to be conveyed to other processing steps.

For the shrinking of the fabric T, the machine 1 comprises an intermediate body 7 arranged next to the flexible belt 2 between the inlet roller 4 and the outlet roller 5. On the outer surface 8 of the intermediate body 7, a stretch 9 can therefore be identified which, with a corresponding stretch 10 of the flexible belt 2, forms a sliding channel 11 for the fabric.

Therefore, the flexible belt 2, during its sliding around the inlet roller, sees at least its outer surface extend. In this situation, it receives the fabric T, supporting it. Next, the same flexible belt 2 is subjected to at least one curvature decrease. As a consequence, the same outer surface of the flexible belt 2 is shrunk, which induces a shrinking of the fabric T.

The aforementioned sliding channel 11 advantageously allows, first of all, to keep the fabric T arranged in contact with the flexible belt 2 during its shrinking. Furthermore, since the intermediate body 7 is typically heated, in the channel 11 there is a heat transfer to the fabric T in order to stabilize its shrinking. In other words, the shrunk fabric is ironed in the channel 11.

From the drawings it can be observed that the stretch 9 of the intermediate body 7 which shares the construction of the channel 11 is convex. Moreover, the intermediate body 7 is arranged in contact with the flexible belt 2 in the corresponding stretch 10. In this way, the corresponding stretch 10 is shaped with a concavity 15 which in substance is immediately downstream of the convexity 16 generated by the inlet roller 4. Consequently, the flexible belt 2, in the transition from the convexity 16 to the concavity 15, also undergoes a bending inversion which ends the shrinking effect exerted on the fabric T. In other words, advantageously, the fabric T, which is arranged in contact with the belt 2 in its extended stretch corresponding to the convexity 16, starting from a surrounding area of the curvature inversion point, is substantially shrunk by the narrowing of the belt 2 in the concavity 15.

Obviously, this feature should not be considered as a limiting feature for the invention. As can be deduced from the foregoing, in fact, for the purposes of fabric shrinking, a reduction of the curvature of the flexible belt is sufficient, the zeroing or the inversion of the same allowing only to increase the shrinking effect. In this sense, therefore, according to a variant embodiment of the invention, not shown in the figures, the sliding channel is rectilinear, with the absence of the curvature inversion point of the flexible belt.

The intermediate body 7 contributes to shrinking, primarily by favouring the change in curvature of the belt 2. Moreover, it is generally heated to perform the ironing of the fabric T mentioned above so as to stabilize shrinking over time.

According to an aspect of the invention, in order to ensure the best possible adhesion of the fabric T to the belt 2 in correspondence with the inlet roller 4 (that is, in the stretch of maximum extension of the belt 2), the shrinking machine 1 also comprises a metal mesh 18 arranged in contact with the flexible belt 2 a starting from a point of the belt 2 in correspondence of the inlet roller 4 and terminating, as shown in the figures, at a subsequent inlet point 19 of the sliding channel 11 which, in the described embodiment, corresponds to the curvature inversion point of the flexible belt 2. Said metal mesh 18 is supported by a special first cylinder 20 arranged near the inlet roller 4. Obviously, the presence of the first cylinder must not be considered limiting for the invention, the metal mesh being able to be supported by any other type of component.

Advantageously, therefore, the metal mesh 18 keeps the fabric T in position until after the inlet point 19 of the sliding channel 11 , i.e. up to the shrinking area of the fabric T itself.

It replaces the sheet used in known equivalent machines to make the so- called "shoe", but has a particularly increased wear resistance, thereby reducing maintenance work on the machine.

Although it is metallic, since the used shoe is a mesh, it has flexibility and ductility characteristics at least equal to those of sheets commonly used in equivalent known machines.

Although it has just been said that the metal mesh 18 terminates at a subsequent point with respect to the inlet point 19, it is clear from the above that this aspect must not be considered limiting for the invention. According to some embodiments not shown in the figures and in any case falling within the scope of protection of the present patent, it terminates at a point subsequent to said inlet. In particular, it is noted that in the embodiment shown in the figures the reference point is the inversion point of the curvature of the flexible belt. In the absence of concavity in the trajectory covered by the fabric, the curvature inversion point is absent and in this case the reference is constituted by the inlet point in the sliding channel.

Since the action of the metal mesh 18 results in a pressure exerted on the fabric T towards the belt 2, according to the embodiment which is described, the starting point of this action is located laterally to the inlet cylinder 4 positioning the first cylinder 20 at least sideways to the same inlet cylinder 4.

Advantageously, therefore, the metal mesh 18 is also shaped with a convexity 22. This shaping allows a pressure action of the mesh 18 on the fabric T which accentuates its adherence to the belt 2.

Since, from what has been said, it is clear that one aspect of the shrinking machine 1 of the invention is the increase of the pressure exerted by the metal mesh 18 on the fabric T against the flexible belt 2 at least in correspondence with the inlet roller 4, the same metal mesh 18 is subject to greater stresses that do not compromise its integrity due to its tenacity, which the sheets used in equivalent known machines would not allow.

Advantageously, therefore, the shrinking machine 1 of the invention allows to considerably increase the tensioning of the shoe and its consequent effects on the fabric T with respect to what happens in the known equivalent machines.

According to another aspect of the invention, the metal mesh 18 is of the type woven on a loom, to optimize its flexibility, but also this aspect must not be considered limiting for the invention.

In any case, the same metal mesh 18 is also subjected to abrasion treatment with abrasive paste that not only smooths out any protrusions, but also fills any depressions, reducing the roughness.

According to another aspect of the invention, the metal mesh 18 is also subjected to a polishing treatment to obtain the most optimal result possible.

Obviously, as in the case of weaving, also the abrasion and polishing processes are non-limiting characteristics for the invention.

Since one of the drawbacks of the known art is constituted by the fact that it is not always possible to correctly adhere the fabric T to the belt 2, especially in the case of difficult fabrics, it is observed that the machine 1 of the invention, using a mechanically more substantial shoe, also improves this aspect.

However, to accentuate this value, according to another aspect of the invention, the machine 1 also comprises a pair of tensioning elements 25 of the metal mesh 18 arranged at the end portions of the metal mesh 18 itself.

This advantageously allows increasing the thrust force exerted by the metal mesh 18 on the fabric T towards the belt 2. This force allows to adhere to the belt 2 also fabrics T that usually "refuse" shrinking.

Since the metal mesh 18 is, as said, tenacious but flexible, this increase in tension does not subject it to increased wear risks.

Still advantageously, this pressure makes it possible to increase the adhesion of the fabric T in the stretch of greater extension of the flexible belt 2 and, consequently, to increase the shrinking effect exerted on the fabric T in the subsequent compression of the belt 2.

Since the increase in pressure exerted is in fact discharged on the flexible belt 2 and on the underlying inlet roller 4, this feature could force to increase the dimensions of the inlet roller 4 to avoid possible unwanted bending. This increase in size, however, would decrease the shrinking effect exerted on the fabric T.

To avoid this, according to another aspect of the invention, the shrinking machine 1 comprises a support body 26 of the inlet roller 4. In the embodiment that is described, the support body 26 is constituted by a support roller 27 located below the inlet roller 4, but this aspect must not be considered limiting for the invention.

Likewise, the number and/or the embodiment of the flexible belts, of the rollers, of the intermediate bodies, of the metal meshes and of the tensioning elements must not be considered as limiting.

With regard to the latter, according to another aspect of the invention, a first of them consists of the first cylinder 20 which supports a first end portion of the metal mesh 18 retaining it.

According to a further aspect of the invention, a second 30 of the tensioning elements 25 is constituted by means for fixing the second end portion of the metal mesh 18 to the outer surface 8 of the intermediate body 7.

The embodiment of the aforesaid fixing means is indifferent to the scope of protection of the present patent, since they can consist of adhesives, screw means, joints made on the intermediate body or other.

What is evident in the first instance is that, according to this embodiment, the intermediate body 7 is a fixed and non-moving element. In this sense, the embodiment of the same represented in the figures and constituted by a cylinder must not be considered as limiting the invention. In particular, the intermediate body 7 can have any shape and profile.

However, even these aspects of the invention should not be considered as limiting. In particular, according to an embodiment variant not shown in the figures, the second tensioning element comprises means for thrusting the second end portion of the metal mesh against the outer surface of the intermediate body. In this sense the latter could be rotating and therefore shaped like a cylinder or similar. A further embodiment of the machine of the invention, not shown in the figures, shows the second tensioning element comprising a second cylinder to which the second end portion of the metal mesh is stably coupled. In particular, the second cylinder is arranged operatively downstream of the intermediate body, for example near the outlet roller. Even in this case, obviously, the intermediate body can be rotating.

In light of the foregoing, it is understood that the shrinking machine of the invention achieves all the prefixed purposes.

In particular, thanks to the use of a metal mesh as a shoe, the machine of the invention requires less maintenance work on the shoe compared to the equivalent known machines.

On closer inspection, the shrinking machine of the invention allows the correct processing also of difficult fabrics which in the known machines tend to refuse shrinking.

The invention may be subject to many changes and variations, which are all included in the appended claims. Moreover, all the details may furthermore be replaced by other technically equivalent elements, and the materials may be different depending on the needs, without departing from the scope of protection of the invention defined by the appended claims.

Claims

C L A I M S

1 . A shrinking machine for fabrics (T), comprising:

at least one flexible belt (2) for supporting and transporting a fabric (T), said flexible belt (2) being arranged in a closed loop around at least one inlet roller (4) and at least one outlet roller (5);

at least one intermediate body (7) of which at least one stretch (9) of the outer surface (8) identifies with a corresponding stretch (10) of said flexible belt (2), between said two rollers (4, 5) a sliding channel (11 ) for the fabric (T);

at least one metal mesh (18) arranged in contact with said flexible belt (2) starting at least from one point corresponding to said inlet roller (4) and terminating at a point coinciding with or following the inlet point (19) of said sliding channel (11 ).

2. Shrinking machine according to claim 1 , wherein said metal mesh (18) is of the type woven on a loom.

3. Shrinking machine according to claim 1 or 2, wherein said metal mesh (18) is of the type abraded with abrasive paste.

4. Shrinking machine according to any of the preceding claims, wherein said metal mesh (18) is of the type subjected to a polishing process.

5. Shrinking machine according to any of the preceding claims, wherein said at least one stretch (9) of said outer surface (8) of said intermediate body

(7) is convex and arranged in contact with said corresponding stretch (10) of said flexible belt (2) to reverse the curvature of said flexible belt (2).

6. Shrinking machine according to any of the preceding claims, comprising at least one pair of tensioning elements (25) of said metal mesh (18) arranged at the end portions of said metal mesh (18).

7. Shrinking machine according to any of the preceding claims, comprising a support body (26) for said inlet roller (4).