CN116745481A

CN116745481A - Processor for shrinking and dimensionally stabilizing fabrics

Info

Publication number: CN116745481A
Application number: CN202180088699.XA
Authority: CN
Inventors: S·桑奇尼
Original assignee: Pantek Textile Machinery Co ltd
Current assignee: Pantek Textile Machinery Co ltd
Priority date: 2020-11-04
Filing date: 2021-11-03
Publication date: 2023-09-12
Also published as: WO2022096530A1; TW202225517A; IT202000026290A1; EP4240892A1

Abstract

A treatment machine for shrinking and dimensionally stabilizing a fabric, provided with at least one module comprising a first fabric accumulation station and a second fabric accumulation station, an alternating movement path of the fabric between the two accumulation stations, such that the fabric moves from the first accumulation station to the second accumulation station and vice versa, and an air distribution system on the fabric at least between the accumulation stations along the movement path, characterized in that the air distribution system comprises, in a middle region of the movement path, a formation region of free loops of fabric and a detection device of fabric loops in the formation region, such that during the alternating movement of fabric between the accumulation stations, the fabric is moved, retaining free loops within the formation region.

Description

Processor for shrinking and dimensionally stabilizing fabrics

Technical Field

The present invention relates to the field of industrial systems for producing and treating fabrics. More particularly, the present invention relates to a treatment machine for shrinking and dimensionally stabilizing fabrics, and also to a treatment method for shrinking and dimensionally stabilizing fabrics. The treated fabric may be a weft/warp fabric, an open width or tubular knit fabric or a nonwoven fabric.

Background

It is known that finishing knitwear items, generally made of cotton or cellulose fibres, as well as knitwear items made of synthetic fibres, have the aim of providing the fabric with considerable dimensional stability, in addition to providing aesthetic and tactile characteristics to the knitwear item, which is the basis for making the finished garment.

Currently, the process for continuous open width finishing of knitted fabrics results in products with a significantly poor hand, i.e. fabrics that do not have a depth of knitting effect.

In order to obtain knitted fabrics with dimensional stability and acceptable quality of soft and light hand, discontinuous processes in rope form are currently used, which are carried out in rotating drums or cylinders of the same type as those used in laundry.

This type of finishing has a high cost due to the high energy and labor consumption, as each roll of fabric must be inserted into the machine, handled and then removed from the machine. All these steps result in high energy losses and lengthy and thus expensive manual operations, which moreover have to be carried out by professionals.

Furthermore, due to the discontinuous nature of the process, it is not possible to obtain sufficient uniformity of the final effect of finishing of the various fabric rolls.

There are processors in which a fabric is inserted into a chamber in which the fabric vibrates to allow the fibers to shrink. Such a machine is described, for example, in patent document W02010/064130. However, the results of shrinkage and expansion of the fabric are not entirely satisfactory.

There are also machines in which the fabric is made to pass through a chamber containing a water tank and vibrating rollers onto which water is sprayed so that wet steam is present in the chamber. Such a machine is described in patent document JP1314777, which allows the fabric to expand. In this case, the shrinkage and expansion of the fabric are also unsatisfactory.

Continuous treatments are also known in which the fabric moves through the treatment station in rope form (i.e. the continuous fabric is "twisted" about the longitudinal axis in the form of strands), however, this has some drawbacks due to the creation of folds in the fabric. Furthermore, longitudinal tension is generated on the fabric, making the objective of dimensional stability virtually impossible.

Disclosure of Invention

The main object of the present invention is to produce a finishing machine for fabrics which also allows to obtain excellent dimensional stability.

Another important object of the present invention is to produce a finishing machine for fabrics which allows to obtain excellent shrinkage of the treated fabric.

Another important object of the present invention is to produce a finishing machine for fabrics which allows to obtain soft fabrics with excellent "hand".

Another important object of the present invention is to produce a treatment machine for finishing fabrics which allows to obtain fabrics with good bulk.

It is a more important object of the present invention to develop a treatment method for fabrics which allows to obtain optimal shrinkage and stabilization of the fabric and optimal tactile properties.

These and other objects, which will become more apparent hereinafter, are achieved by a treatment machine for shrinkage and dimensional stabilization of fabrics, provided with at least one module comprising: a first fabric accumulation station and a second fabric accumulation station; an alternating path of movement of the fabric between the two accumulation stations such that the fabric moves from the first accumulation station to the second accumulation station and vice versa; and an air distribution system on the fabric along a path of movement at least between the accumulation stations; the machine is distinguished in that it comprises, in a central position of the path of movement, a formation zone of free loops of fabric and detection means of the loops of fabric in the formation zone, so that during the alternating movement of fabric between the accumulation stations, the fabric moves in such a way as to retain the free loops inside the formation zone.

The fact that the fabric has free loops along its path of movement means that between the accumulation stations the fabric has a very low longitudinal tension, i.e. is not tensioned.

By free loop is meant a portion of the fabric that forms a convex curve (convex downward) in this forming region, primarily due to gravity.

Advantageously, along said movement path, alternate movement means are provided, comprising two intermediate movement surfaces on which the fabric is suitable to be supported; these moving surfaces are separated from each other by areas that do not support the fabric, defining free loop forming areas such that the fabric is continuously disposed on the intermediate surfaces with free loop portions between the surfaces.

Preferably, the movement means comprise two movement members defining an intermediate movement surface, preferably to move the fabric in coordination, i.e. even with eventually different inclinations, the two movement members move the fabric in the same general direction between the two accumulation stations.

Preferably, the moving member is a conveyor belt, preferably closed in a loop, defining on its upper active portion an intermediate moving surface on which the fabric is supported.

Preferably, the conveyor belt is inclined from bottom to top in the direction from the accumulation station to the endless loop area.

Preferably, the conveyor belts comprise means for adjusting their inclination with respect to the ground, so as to be able to adjust the distance of the lower ends with respect to the accumulation grooves of the accumulation stations, which are arranged below these lower ends, with consequent adjustment of the curvature of the fabric in this lower end of the belt.

Advantageously, in a preferred embodiment, the machine comprises a controller controlling the speed of at least one intermediate moving surface, such that if the loop detection means detects the absence or presence of an excess loop in the forming zone, the controller modifies the speed of at least one intermediate moving surface to recover the correct amount of loop in the forming zone. For example, if the free loop detection means detects the absence of a loop, the machine may slightly increase the speed of the first intermediate moving surface, or slightly decrease the speed of the second intermediate moving surface (i.e., create a speed differential between the two surfaces); in this way, a small amount of fabric will accumulate in the forming zone, extending the free loop in a downward direction until the detection means detects the loop and commands the intermediate surface of the speed change to return to the normal speed. Furthermore, the ring detection means can verify that there is an excess of rings in the downward direction and therefore the machine changes (in a manner opposite to that described above) the speed of one of the intermediate moving surfaces.

For example, the ring detection device is a device having an optical sensor, for example. For example, the optical sensor is provided with a laser that directly reads the ring of fabric, for example through a window located under the ring or an axis inclined with respect to the fabric, or with an indirect reading system using an optical fiber adapted to operate at high temperature.

Another type of ring detection device may be manufactured, for example, with an ultrasonic type of position transducer mounted under the ring.

Other examples of loop detection means may include mechanical probes that detect the presence of a loop.

According to a preferred embodiment, the air distribution system has air ejectors facing the intermediate moving surface and suction zone of the fabric, operatively connected to the facing suction duct, placed opposite these ejectors with respect to the moving surface, such that air is ejected from the ejectors to pass through the fabric placed on these surfaces and to be sucked by the suction duct; the effect of the air on the fabric is to push it precisely onto the intermediate moving surfaces against which they are blocked, so that the fabric is in fact stationary with respect to these surfaces, moving more or less with it between the respective accumulation stations and the formation areas of the loops, and vice versa.

Advantageously, in a preferred embodiment, the air ejector is operatively connected to an air heating device. Preferably, the heating device has an air inlet pipe operatively connected to the environment surrounding the accumulation station such that at least a portion of the air heated by the device is taken from the environment in which the station is enclosed: preferably, the air inlet duct is provided with a fan to move air within the duct towards the injector.

Preferably, the suction duct is operatively connected to a suction fan operatively connected to the exhaust outlet duct such that at least a portion of the sucked air is drawn from the environment in which the accumulation station is enclosed.

According to a preferred embodiment, the module of the machine has a humidity sensor of the fabric; more preferably, the machine comprises a controller controlling the amount and/or speed of the air fed towards the fabric and/or a controller controlling the heating temperature of the air fed into the movement path based on the humidity value detected by the humidity sensor. This allows an optimal adjustment of the drying time (i.e. effect) of the fabric during the alternating movement between the two accumulation stations.

In a preferred embodiment, the module of the machine comprises only two accumulation stations, insertion means for inserting the fabric into the first accumulation station, and extraction means for extracting the fabric from the second accumulation station, both the insertion means and the extraction means being adapted to move the fabric with the same movement speed, which is lower than the speed at which the fabric alternates between said two accumulation stations by movement of said supporting surface of the fabric; advantageously, in the following, the speed of the alternating movement is also referred to as first speed, while the speed of the insertion and extraction from the modules is defined as second speed.

Preferably, the first speed of the alternating movement between the two accumulation stations is at least three times the second speed, and more particularly at least five times the second speed, and even more preferably from nine to eleven times the value of the second speed; in other examples, the first speed may be greater than eleven times the value of the second speed.

Preferably, the insertion device comprises an initial moving surface of the fabric, the fabric being adapted to be arranged on the initial moving surface; preferably, the insertion device comprises a movement member defining an initial movement surface, which moves the fabric towards the first accumulation station; preferably, the movement member is a conveyor belt, preferably closed in a loop, defining an initial movement surface on the upper active part, preferably the conveyor belt is inclined from top to bottom in the direction of insertion of the fabric, preferably with the possibility of adjusting the inclination.

Preferably, the extraction means comprise a final moving surface of fabric suitable for being arranged on the final moving surface; preferably, the extraction device comprises a movement member defining a final movement surface, which moves the fabric from the second accumulation station towards the outside of the module; preferably, the moving member is a conveyor belt, preferably closed in a loop, defining a final moving surface on the upper active part, preferably inclined from bottom to top in the extraction direction of the fabric, preferably with the possibility of adjusting the inclination.

In a preferred embodiment, the machine comprises a plurality of the aforementioned modules arranged in series with respect to each other, and wherein the fabric is adapted to move alternately in each module between the first accumulation station and the second accumulation station at a first speed, between said modules in a single direction of forward movement at a second speed lower than the first speed, so that the fabric as a whole passes through the machine at the second speed.

Preferably, between successive modules, the fabric is adapted to be transferred from the final moving surface of the extraction means of the module from which the fabric exits to the initial moving surface of the insertion means of the module into which the fabric enters, and wherein a further forming zone of the free loop of fabric and a further detection means of the loop of fabric in this further forming zone are provided between the extraction means and the insertion means, so that during the movement of the fabric between the extraction means and the insertion means of two successive modules, the fabric forms a free loop in the forming zone.

Preferably, the air distribution system has a further air ejector facing the initial and final moving surfaces of the fabric, and a facing further air suction duct arranged opposite to the further ejector with respect to the initial and final moving surfaces, such that air is ejected from the further ejector to pass through the fabric arranged on the initial and final moving surfaces, and is sucked by said further suction duct such that the fabric is stationary with respect to, i.e. moves with, these surfaces; preferably, the further air ejector is operatively connected to the air heating device.

Preferably, also in this case, the machine comprises a controller controlling the speed of at least one of the final and initial moving surfaces of the extraction and insertion devices of the two adjacent modules, so that if the further loop detection device detects the absence or presence of an excess loop in the further forming zone, the controller adjusts the speed of at least one of the final and initial moving surfaces to recover the correct amount of loop in the further forming zone.

According to a preferred embodiment, the distribution system comprises a controller that controls the temperature of the air supplied into each module so that in each module the air can be distributed onto the fabric at a desired temperature, independently of the temperature of the air distributed into the other modules.

According to a preferred embodiment, the machine comprises means for managing the fabric reserves in the accumulation stations, which generate commands to reverse the movement of the fabric between the accumulation stations; preferably, the means for managing the reserve comprise means for evaluating the quantity of fabric in the accumulation stations, adapted to command the reversal of movement between the accumulation stations when a given minimum value of accumulated fabric is reached, or means for managing the reserve comprise means for evaluating the tension of fabric exiting from the accumulation stations, such that the reversal is commanded when a tension value equal to or greater than a threshold value is reached, or a combination of said means for evaluating the quantity of fabric and means for evaluating the tension of fabric. For example, international patent application PCT/EP2020/067091 describes a device for evaluating the tension of a fabric leaving an accumulation station.

For example, the apparatus for managing fabric reserves in accumulation stations comprises:

means for evaluating the amount of fabric included in the relative station, such that when said means detect that the amount of fabric in said station is below a limit threshold, a command is generated to reverse the movement of fabric extracted from said station,

-means for evaluating the tension of said fabric, and

-an electronic program adapted to change the value of the limit threshold based on the tension of the fabric detected by the means for evaluating tension.

Preferably, if said means for assessing the tension of said fabric verifies a critical state of the tension of said fabric when the means for assessing the amount of fabric detect that the amount of fabric is below said limit threshold, said program modifies said limit threshold of the amount of fabric in said station, increasing it by a predetermined value.

Preferably, the device is adapted to store the number of events in which the evaluation device detects that the amount of fabric in the station is below a limit threshold, i.e. the number of reversals associated with a decrease in fabric in the relevant station; if the device detects a predetermined continuous number of the events, the electronic program modifies the limit threshold for the amount of fabric in the station to decrease it by a predetermined value.

In practice, it is advantageous to control the fabric reserve on the accumulation station for insertion and extraction by means of a device for evaluating the quantity of fabric (for example a weight measuring device such as a load cell) which, by means of appropriate settings, determines when the accumulation station is empty and therefore when the device reverses the movement of the fabric; if the control value of the load sensor is not adjusted to the correct value, two situations can occur: either an excessive fabric reserve is maintained at the accumulation station or the fabric is tensioned; detecting the tension of the fabric by means for evaluating the tension (for example of the mechanically operated type), and in this case automatically increasing the control value of the load sensor of the accumulation station; if during the subsequent reversal the means for assessing tension is triggered again, the control value of the load sensor will be further increased, and so on, until the means for assessing tension is no longer triggered; in this way, tensioning of the fabric is avoided. At the same time, however, there may be an excessive fabric reserve in the accumulation station; to remedy this, the control value of the load sensor is reduced after a certain number of reversals of the fabric feed have been successfully completed, i.e. in the event that the means for evaluating the tension are not triggered; after the same number of successful reversals has been completed, the control value of the load cell will be further reduced. This will continue until the means for assessing tension is triggered again and thus the control value of the load sensor increases again.

With this system, the control value of the load cell is self-regulating so that the fabric reserve on the accumulation station is not excessive and the fabric is protected from stretching and tensioning.

Preferably, the modification of the limit threshold of the amount of fabric in the station is performed by equal increasing or decreasing values.

Preferably, each accumulation station comprises an accumulation tank associated with the management means.

Preferably, the accumulation tank is hinged according to a horizontal axis, allowing the tank to tilt.

Preferably, the means for evaluating the amount of fabric in the accumulation station comprise at least one load sensor, which is connected to said accumulation tank, preferably by means of a connecting member. Preferably, the load sensor is arranged above the accumulation tank, fixed to the support structure and connected to the accumulation tank by means of a connecting member (e.g. a rope or a rod) such that the load sensor is adapted to act in traction, or the load sensor is arranged below the accumulation tank, fixed to the support structure and connected to the accumulation tank by means of a connecting member such that the load sensor is adapted to act in compression.

Preferably, the means for assessing the tension of the fabric comprise a movable stop constrained to the support structure and adapted to move from a rest position to an activated position and vice versa, and a sensor element adapted to recognize the movement of the movable stop from the rest position.

According to a preferred embodiment, the machine comprises one or more modules, means for inserting the fabric continuously from outside the machine into the first module, and means for extracting the fabric continuously from the last module (in the case of a machine with a single module, the first and last modules coincide), so that the machine processes the fabric continuously and can be advantageously inserted into a continuous fabric production line.

According to a preferred embodiment, each module defines a suitable treatment chamber having an inlet for the continuous feed of the fabric and an outlet for the continuous extraction of the fabric.

According to other preferred embodiments, the machine is adapted to process individual portions of fabric accumulated in said accumulation station during a working cycle, i.e. to process fabric discontinuously.

According to another aspect, the invention relates to a treatment method for shrinking and dimensionally stabilizing a fabric, which method is preferably carried out by a machine according to one or more of the above-described preferred embodiments and examples, wherein in at least one treatment chamber the fabric is alternately accumulated in a first accumulation station and a second accumulation station by an alternating forward and return movement of the fabric along a movement path between the two accumulation stations, and wherein during the movement the fabric is impacted by a flow of air, preferably hot.

Preferably, the fabric is supported on both moving surfaces along the path of movement and is not supported in the free loop forming region between the moving surfaces, such that during movement, the free loop is formed in the forming region by gravity (i.e. is not supported from below).

Preferably, the presence of free loops of the fabric between the moving surfaces is monitored during movement of the fabric.

Preferably, if the absence or presence of an excess of free loops is detected in the forming zone, the speed of at least one of the moving surfaces is modified to recover the correct amount of loops in the forming zone.

Preferably, the humidity of the fabric in the chamber is detected and if this value is outside a given operating range, the amount and/or speed of air supplied towards the fabric is changed and/or the temperature of the air is changed.

Preferably, the air that heats the fabric passes through the fabric disposed on the moving surface and is drawn from beneath the surface such that the fabric disposed on the surface remains substantially stationary relative to the surface during movement of the surface.

Preferably, when an accumulated fabric amount equal to or less than a threshold value is measured in the stations or a tension of fabric exiting from an accumulating station is measured to be equal to or greater than a threshold value, a reversal of the movement of fabric between the accumulating stations occurs, or a reversal of the movement of fabric between the accumulating stations occurs according to the operation of the above-described means for managing reserves.

Preferably, the fabric is continuously moved through one or more chambers, the input and output speed of the fabric into/out of said chambers being lower than the movement speed of the fabric between said accumulation stations of each chamber; preferably, the speed of the alternating movement between the two accumulation stations is at least three times as high as the input and output speed of the fabric entering/exiting the chamber, and more particularly at least five times as high as the input and output speed of the fabric entering/exiting the chamber, and even more preferably between nine and eleven times the input and output speed value of the fabric entering/exiting the chamber, preferably the speed of the alternating movement is greater than eleven times the input and output speed value of the fabric entering/exiting the chamber.

According to a preferred embodiment, the formation zone of the free loop of fabric is present between two consecutive treatment chambers and is defined between the moving surfaces of the fabric for extracting the fabric from the chambers and inserting the fabric into the chambers, respectively; preferably, the presence of free loops of the fabric between the moving surfaces is monitored during movement of the fabric; preferably, if the absence or presence of an excess of free loops in the forming region is detected, the speed of at least one of the moving surfaces is modified to recover the correct amount of loops in the forming region.

According to other preferred embodiments, the method is adapted to treat a single portion of fabric accumulated in said accumulation station during a working cycle, or to treat fabric discontinuously in said chamber, so that all fabric to be treated is inserted into the chamber and subsequently treated, then extracted from the chamber.

With respect to the treatment machine and with respect to the method, the treated fabric may be of various types, such as weft/warp fabric, open width or tubular knitted fabric or nonwoven fabric.

Furthermore, the fabric may be treated in open width inside the treatment machine, i.e. with the end (selvedge) kept open at the maximum height, so that the fabric assumes an expanded configuration.

The fabric may also be treated in rope form, i.e. the fabric is treated to "compress" the selvedge along the transverse axis. During processing, the fabric is twisted along the longitudinal axis.

The fabric may also be treated in a semi-rope form, i.e. the fabric is treated to "compress" the selvedge along the transverse axis. During treatment, the fabric is accompanied to prevent it from twisting along the longitudinal axis.

Drawings

The invention will now be better understood by the following description and accompanying drawings, which show non-limiting examples of embodiments of the invention. More particularly, in the accompanying drawings:

Fig. 1 shows a schematic view of a machine module according to the invention;

FIG. 2 shows a schematic view of a machine formed from a plurality of modules as in FIG. 1;

fig. 3 shows a schematic view of a machine according to the invention formed by several modules sharing a common chamber;

fig. 4 shows a schematic view of another machine according to the invention formed by several modules sharing a common chamber in a variant with respect to the case of fig. 3;

fig. 5 shows a schematic top view of another machine according to the invention, formed in sequence by a plurality of modules defining a C-shaped movement path of the fabric.

Detailed Description

Referring to the above figures, a treatment machine for shrinkage and dimensional stabilization of fabrics according to the present invention is generally indicated by reference numeral 10.

The machine may be modular and thus formed by a single module, or by a plurality of modules arranged in succession to one another, with the fabric being transferred continuously from one module to the other.

Fig. 1 shows an example of a machine module, indicated generally at 10A. The module 10A may be part of a machine having a single module (as shown in fig. 1) or part of a machine having multiple identical modules (as shown in fig. 2).

Each module 10A is defined by a chamber 11 provided with walls defining a treatment environment, inside which two accumulation stations of fabric T in folds are provided, a first accumulation station 12 and a second accumulation station 13, respectively. In other examples, a machine having a continuous plurality of modules may have a plurality of modules provided with two respective accumulation stations arranged in series within a single chamber, as shown for example in fig. 3 or 4 (in which case the modules share at least a portion of the air heating system and the exhaust outlet, as will be more clearly shown below).

Each accumulation station comprises, for example, a respective accumulation tank 12A and 13A, preferably hinged at one of its ends 12A ', 13A' to a structure integral with the chamber according to a horizontal axis.

An alternate movement path 14 of the fabric T is provided between the two accumulation stations 12 and 13, so that the fabric moves from the first accumulation station 12 to the second accumulation station 13 and vice versa according to the logic explained below.

A system 15 for distributing air over the fabric along a movement path 14 (i.e. between the accumulation stations 12 and 13 and preferably also at the inlet and outlet of the module as described below) is also associated with the module 10A.

An alternating movement device 16 of the fabric, which comprises means for moving the fabric, in the form of, for example, closed-loop conveyor belts 17 and 18, defining on their upper active portions the movement surfaces of the fabrics 17A and 18B, which are defined hereinafter as intermediate movement surfaces of the fabric, is arranged between the accumulation stations 12 and 13 along the movement path 14 of the fabric T. In the following, conveyor 17 and conveyor 18 will also be referred to as first conveyor and second conveyor, associated with their dedicated accumulation stations.

The conveyors 17 and 18 are inclined from bottom to top in a direction from the accumulation station towards the other conveyor.

Characterized in that between the intermediate moving surfaces 17A and 18A, or between the conveyor belts 17 and 18 (i.e. in the middle of the path of movement), there is provided a zone where the fabric is not supported, defining a forming zone 19 of the free loop T1, so that the fabric T is arranged continuously on the intermediate surfaces 17A, 18A, with a portion in the form of a free loop T1 between these surfaces (i.e. between the facing ends of the conveyor belts 17 and 18). The fact that the fabric has a free loop along the movement path 14 means that the fabric between the accumulation stations 12 and 13 has a very low longitudinal tension, i.e. it is not tensioned.

It should be noted that the free ring forms a convex curve in this forming region due to gravity, the convex surface of the convex curve facing downwards.

Advantageously, the means 20 for detecting the loops of fabric are arranged in this forming zone 19, so as to move the fabric during the alternating movement of the fabric T between the accumulation stations 12 and 13, so as to maintain the free loops T1 within the forming zone 19. For example, the coil detection device is a device with an optical sensor provided with a laser that directly reads the coil of the fabric, for example through a window positioned below the coil or with an axis inclined with respect to the fabric.

Advantageously, the conveyor belts 17 and 18 comprise means for adjusting their inclination with respect to the ground, so as to be able to adjust the distance of the lower ends 17'-18' with respect to the accumulation grooves 12A and 13A of the accumulation stations 12 and 13 disposed below these lower ends, so as to adjust the curvature of the fabric at the lower ends of the conveyor belts. For example, the tilt adjustment means comprise a hinge with a horizontal axis for the respective conveyor belt, for example at the rotation axis of an idler rotor provided at the upper end of the belt. Naturally, the inclination adjustment device also comprises means for blocking the conveyor belt in a desired inclined position, not shown in the figures.

The intermediate moving surfaces 17A and 17B move the fabric at the same speed, so that the amount of free loops in the forming region 19 is substantially constant, at least during normal movement. The module 10A includes a controller that controls the speed of at least one of the intermediate moving surfaces 17A and 17B such that if the free loop detection device 20 detects the absence or presence of an excess loop T1 in the forming zone 19, the controller modifies the speed of at least one of the intermediate moving surfaces 17A and 17B to restore the correct amount of loop T1 in the forming zone 19.

For example, if the free loop detection device 20 detects the absence of loop T1 (or the presence of a negligible amount), the controller allows the speed of the first conveyor belt 17 to increase slightly, or the speed of the second conveyor belt 18 to decrease slightly (or more generally, a speed difference is created between the two intermediate moving surfaces 17A and 18A). Thus, the fabric accumulates in the forming zone 19, elongating the free loop T1 downwards until the detection means 20 detect the loop and command the intermediate surface of the speed change to return to the normal speed.

Furthermore, the ring detection device 20 can verify that there is an excess of rings T1 in the downward direction, and therefore the machine changes (in a manner opposite to that described above) the speed of one of the intermediate moving surfaces.

The air distribution system 15 has air ejectors 21 facing the intermediate moving surfaces 17A and 17B, i.e. arranged above the first and second conveyor belts 17 and 18, which allow drying of the fabric on the conveyor belts 17 and 18.

Furthermore, the air distribution system 15 has a suction zone 22 operatively connected to a suction duct 23 and opposite the ejector 21 with respect to the moving surfaces 17A and 17B.

For example, each intermediate moving surface 17A and 17B comprises a respective group of ejectors 21 and a respective suction zone 22.

In practice, air f is ejected from the ejector 21 toward the conveyor belts 17 and 18. The air passes through the fabric disposed on the conveyor and the upper surface of the conveyor supporting the fabric to be sucked into the suction zone 22. From the suction zone, the air sucked by the suction device 24 enters the suction duct 23 and from there reaches the exhaust outlet flue 25, so that at least part of the sucked air is extracted from the chamber 11, i.e. from the environment enclosed by the accumulation station.

In addition to the drying effect, the effect of the air f on the fabric T arranged on the conveyor belt is to push it precisely against the intermediate moving surfaces, blocking them against them, so that the fabric is in fact stationary with respect to the surfaces 17A-18A, i.e. moves more or less with them, preventing friction of the fabric on these surfaces.

The air distribution system 15 comprises air heating means 26 arranged along an air intake duct 27 which draws air from inside the chamber 11 and sends it to the ejector 21, so that at least a portion of the air heated by the means 26 is extracted from the environment surrounding the accumulation stations 12 and 13. A fan 28 is provided along the intake pipe to move air in the intake pipe 27 toward the injector 21.

The module has a fabric humidity sensor 29 associated with control of the amount and/or speed of air supplied to the fabric by the air distribution system 15 and/or control of the heating temperature of the air supplied into the path of movement by the heating device 26 based on the humidity value detected by the humidity sensor 29. This allows an optimal adjustment of the drying time, i.e. the drying effect of the fabric during the alternating movement between the two accumulation stations 12 and 13.

For example, to increase the drying speed, the amount of air supplied to the fabric may be increased, such as increasing the amount of fabric or decreasing the speed of alternating movement of the fabric, or alternatively increasing the air temperature, or a combination thereof. Also, when it is desired to reduce the drying speed, the operation may be reversed.

Advantageously, each module 10A comprises insertion means 30 of the fabric T inside the first accumulation station 12 and extraction means 31 of the fabric from the second accumulation station 13, both adapted to move the fabric with the same movement speed, lower than the speed at which the fabric is moved alternately between the two accumulation stations by means of the movement produced by the first and second conveyor belts 17 and 18.

The speed of the alternating movement between the accumulation stations 12 and 13 is defined as a first speed, while the speed of the insertion and extraction from the modules is defined as a second speed. Thus, the second speed corresponds to the speed of the fabric T through the module 10A.

For example, the first speed of the alternating movement between the two accumulation stations 12 and 13 may be at least three times as great as the second speed, and more particularly at least five times as great as the second speed, and even more preferably around ten times as great as the second speed; in other examples, the first speed may be ten times as large as the second speed.

The insertion device 30 is advantageously similar to the member that moves the fabric in an alternating manner between the accumulation stations 12 and 13, i.e. is a third conveyor belt (hereinafter also indicated with reference numeral 30) closed in a loop, the active section of which defines an initial movement surface 30A of the fabric, on which the fabric T is suitable to be arranged.

Also in this example, the third conveyor belt 30 is inclined from top to bottom in the direction of fabric insertion into the first accumulation station 12, for example with the possibility of adjusting this inclination in the same way as the second conveyor belt 18.

Likewise, the extraction device 31 is also advantageously similar to the means for moving the fabric in an alternating movement between the accumulation stations 12 and 13, i.e. a fourth conveyor belt (hereinafter also indicated with 31) closed in a loop, the upper active section of which defines a final moving surface 31A of the fabric, on which the fabric T is suitable to be arranged.

Also in this example, the fourth conveyor belt 31 is inclined from below upwards in the direction of extraction of the fabric from the second accumulation station 13, for example with the possibility of adjusting the inclination in the same way as the first conveyor belt 17.

The air distribution system may have a further air ejector 121 facing the initial and final moving surfaces 30A and 31A of the insertion and extraction devices 30 and 31, and a facing further suction duct 123 arranged opposite to said further ejector 121 with respect to the initial and final moving surfaces 30A and 31A, such that air is ejected from said further ejector 121 to pass through the fabric arranged on the initial and final moving surfaces and sucked by said further suction duct 123, which is for example operatively connected to the flue 25, to eliminate humid air. Advantageously, the further air injector 121 is operatively connected to the air heating device 26 in order to feed heated air onto the fabric.

In the case of a machine with several modules 10A arranged in series, the fabric is adapted to move alternately in each module between the first accumulation station 12 and the second accumulation station 13 at a first speed, while between the following modules and at the inlet of the first module of the series and at the outlet of the last module of the series, the fabric is adapted to move in a single forward direction at the aforementioned second speed (lower than the first speed), so that the fabric as a whole passes through the machine at the second speed.

Thus, in several consecutive modules of the series, between two consecutive modules 10A, the fabric is adapted to pass between the final moving surface 31A of the extraction means 31 of the module from which the fabric exits and the initial moving surface 30A of the insertion means 30 of the following module into which the fabric enters.

Advantageously, a further forming zone 119 of the free loop T1' of the fabric T is provided between the extraction means 30 and the insertion means 31, to which a further detection means 120 of the fabric loop in this further forming zone 119 is associated, so that during the movement of the fabric between the extraction means and the insertion means of two consecutive modules, the fabric forms a free loop in the forming zone, avoiding the tensioning of the fabric, to facilitate the finishing effect.

As in the case of the ring detection device 20, in this case the machine also comprises a control of the speed of at least one of the final moving surface 31A and the initial moving surface 30A of the extraction and insertion device of the two adjacent modules, so that if the further ring detection device 120 detects the absence or presence of an excessive ring in the further forming zone 119, the control modifies the speed of at least one of the final and initial moving surfaces 31A and 30A to recover the correct amount of ring in this forming zone.

In some embodiments of machines having multiple modules in series, the distribution system may be provided with a controller that controls the temperature of the air supplied into each module 10A so that in each module, air can be distributed over the fabric at a desired temperature independent of the temperature of the air distributed in the other modules (e.g., as shown in fig. 2 and 3). Fig. 4 shows a case of multiple modules, for example, within a single chamber, wherein the exhaust extraction systems 23-25 are common to all stations. Again in the example of fig. 4, the heating system may be common to all of the modular stations or independent for each station.

Fig. 5 shows a plurality of modules 10A placed side by side in pairs C1, C2, C3 in a direction transverse to the forward direction of movement of the fabric. Each pair may be formed by modules sharing a portion of the walls of their chambers or simply placed side by side. In this example, there are six modules defining a path formed by a first section in a first direction in which the fabric passes sequentially through three modules belonging to three different pairs, and a second section in a second direction opposite to the first direction, in a sequence opposite to that of the first section, there being an arcuate movement belt G to reverse the direction of movement between the modules of the two sections. This configuration allows for optimization of the space and structure of the resulting module.

For each module 10A (i.e. in the case of a single module and in the case of a plurality of modules in series), the machine comprises means 40 for managing the fabric reserves in the accumulation stations 12 and 13, which generate commands to reverse the fabric movement between the accumulation stations.

For example, this means 40 for managing reserves comprise means 41 for evaluating the quantity of fabric in the accumulation stations, which are adapted to command the reversal of the movement between the accumulation stations when a given minimum value of accumulated fabric is reached.

Alternatively, the means 40 for managing the reserve comprise means 42 for sensing the tension of the fabric exiting from the accumulation station, so that when a tension value equal to or greater than a threshold value is reached, the reversal is commanded.

In this example, the means 40 for managing reserves comprise a combination of these means 41 for evaluating the quantity of fabric and a fabric tension sensor 42.

For example, international patent application PCT/EP2020/067091 describes a device for evaluating the tension of a fabric leaving an accumulation station.

Thus, the means 40 for managing the fabric reserves in the accumulation stations 12 and 13 comprise means 41 for evaluating the amount of fabric included in the relevant station, so that when the evaluation means 41 detect that the amount of fabric in this station is below the limit threshold X, a command is generated to reverse the movement of the fabric leaving said station.

Furthermore, the means 40 for managing fabric reserves also comprise means for sensing the tension of said fabric 42, and an electronic program adapted to adjust the value of the limit threshold value X based on the tension state of the fabric detected by the tension sensor means 42.

If the means for assessing fabric tension verifies the critical state of fabric tension when the means for assessing fabric quantity 41 detects that the fabric quantity is below the limit threshold value X, the program modifies the limit threshold value of fabric quantity in the station, increasing it by a predetermined value.

Advantageously, the means 40 for managing fabric reserves are adapted to store the number of events in which the evaluation device 41 detects that the amount of fabric in a station is below a limit threshold, i.e. the number of reversals associated with the decrease of fabric in the relevant station; if the device detects a predetermined number of said events, the electronic program modifies the limit threshold of the amount of fabric in the station by a predetermined value.

In practice, it is advantageous to control the fabric reserve on the accumulation station for insertion and extraction by means of a device for evaluating the quantity of fabric (for example a weight measuring device such as a load cell) which, by means of appropriate settings, determines when the accumulation station is empty and therefore when the device reverses the movement of the fabric; if the control value of the load sensor is not adjusted to the correct value, two situations can occur: either an excessive fabric reserve is maintained at the accumulation station or the fabric is tensioned; detecting the tension of the fabric by means for evaluating the tension, for example of the mechanically operated type, and in this case automatically increasing the control value of the load sensor of the accumulation station; if during the subsequent reversal the means for assessing tension is triggered again, the control value of the load sensor will be further increased, and so on, until the means for assessing tension is no longer triggered; in this way, tensioning of the fabric is avoided. At the same time, however, there may be an excessive fabric reserve in the accumulation station; to remedy this, the control value of the load sensor is reduced after a certain number of reversals of the fabric feed have been successfully completed, i.e. in the event that the means for evaluating the tension are not triggered; after the same number of inversions have been successfully completed, the control value of the load sensor will be further reduced. This will continue until the means for assessing tension is triggered again and thus the control value of the load sensor increases again.

The limit threshold for the amount of fabric in the station is modified by an equal increment or decrement value.

The means for evaluating the amount of fabric 41 in the accumulation station comprise at least one load sensor connected to the accumulation tanks 12A-13A. For example, a load sensor is arranged above the accumulation tank, fixed to the support structure and connected to the tank by means of a connecting member such as a rope or a rod, so that the load sensor is adapted to function in a traction manner. Alternatively, the load cell is arranged below the groove such that the load cell is adapted to function in a compressive manner.

The means 42 for assessing the tension of the fabric comprise, for example, a movable stop 42A constrained to the support structure and adapted to move from a rest position to an activated position and vice versa, and a sensor element 42B adapted to recognize the movement of said movable stop from said rest position.

In the case of a single module 10A and a plurality of modules 10A arranged in succession, the machine 10 is able to process the fabric continuously (the speed corresponds to the second speed at which the fabric passes between the modules and is inserted and extracted continuously into and from the first and last modules) and is able to be advantageously inserted in a continuous fabric treatment line. In this case, means for inserting the fabric continuously from outside the machine into the first module and means for extracting the fabric continuously from the last module will be provided.

In other examples, the machine is adapted to process a single portion of fabric accumulated in the accumulation station during an operating cycle, i.e. to process fabric discontinuously, so that all fabric is immediately arranged in the machine (with a single module or with multiple modules) (e.g. manually) and subjected to a processing cycle, then extracted from the machine.

The machine thus allows to perform a treatment method for shrinkage and dimensional stabilization of the fabric carried out in at least one treatment module. By alternating forward and return movement of the fabric along the movement path 14 between the two accumulation stations, the fabric is alternately accumulated in the first accumulation station and in the second accumulation station, and wherein during the movement the fabric is impacted by an air flow of suitable temperature.

Along the movement path 14, the fabric is supported on the two movement surfaces 17A and 18A, but not in a free loop forming region 19 defined between the movement surfaces thereof, so that during movement a free loop T1 is formed in this forming region by gravity.

The presence of free loops of the fabric between the moving surfaces is monitored during the movement of the fabric by means of the device 20.

If the absence or presence of an excessive free loop T1 is detected in this formation zone 19, the speed of at least one of said moving surfaces 17A, 18A is modified to recover the correct amount of loops in the formation zone 19.

The humidity of the fabric in the chamber of the module may be detected and if the value is outside a given operating range, the amount and/or speed of air supplied towards the fabric is changed and/or the temperature of the supplied air is changed.

The heated air of the fabric is drawn through the fabric disposed on the moving surfaces 17A and 18A by suction from beneath these surfaces so that the fabric disposed on these surfaces remains substantially stationary relative to these surfaces during its movement.

Advantageously, when the amount of accumulated fabric in the station is measured equal to or less than a threshold value or the tension of the fabric exiting from the accumulation station is measured equal to or greater than a threshold value, the movement of the fabric between said accumulation stations 12 and 13 is reversed, or the operation of the device for managing reserves is reversed according to the above.

The fabric is continuously moving through the modules, with the input and output speeds of the fabric entering/exiting the modules being lower than the speed of movement of the fabric between the accumulation stations 12 and 13 of each module.

According to the treatment method, the speed of the alternating movement of the fabric between the two accumulation stations is at least three times the input and output speed of the fabric entering/exiting module, and more particularly at least five times the input and output speed of the fabric entering/exiting module, and even more preferably between nine and eleven times the input and output speed value of the fabric entering/exiting module.

As mentioned, the formation zone of the free loop of fabric is arranged between two consecutive treatment modules and is defined between the moving surfaces of the fabric for extracting the fabric from the modules and inserting the fabric into the modules, respectively.

During the movement of the fabric, the presence of the free loop of fabric interposed between the moving surfaces and the extraction surface is monitored. If the absence or presence of excess free loops in the forming zone is detected, the speed of at least one of the extraction and insertion motion surfaces is modified to restore the correct amount of loops in the forming zone.

It should be understood that the above only represents possible non-limiting embodiments of the invention, which may vary in forms and arrangements without however departing from the scope of the concept on which the invention is based. Any reference numerals in the appended claims are purely for the purpose of facilitating the reading of the claims in light of the above description and of the accompanying drawings, and do not in any way limit their protective scope.

Claims

1. A processor for shrinkage and dimensional stabilization of a fabric (T), provided with at least one module (10A), comprising: a first accumulation station (12) of fabric and a second accumulation station (13) of fabric; -an alternating movement path (14) of the fabric (T) between the first and second accumulation stations (12, 13), such that the fabric (T) moves from the first accumulation station (12) to the second accumulation station (13), and such that the fabric moves from the second accumulation station to the first accumulation station; and an air distribution system (15) on the fabric at least between the first and second accumulation stations (12, 13) along the movement path (14), characterized in that in a middle region of the movement path (14) there is included a formation region (19) of free loops (T1) of fabric (T) and detection means (20) of fabric loops in the formation region (19) such that during alternating movement of fabric between the first and second accumulation stations (12, 13) the fabric moves in such a way as to retain free loops (T1) within the formation region (19).

2. A machine according to claim 1, wherein alternate movement means (16) are provided along the movement path (14), comprising two intermediate movement surfaces (17A, 18A) on which the fabric (T) is suitable to be arranged, separated from each other by a zone that does not support the fabric, defining a free loop forming zone (19) such that the fabric (T) is arranged continuously on the two intermediate movement surfaces (17A, 18A) with a free loop (T1) portion between the two intermediate movement surfaces (17A, 18A).

3. A machine according to claim 2, wherein said alternate movement means comprise two movement members defining said two intermediate movement surfaces (17A, 18A), said two movement members moving the fabric in coordination.

4. A processor according to claim 3, wherein the moving member is a conveyor belt (17, 18) defining the intermediate moving surface (17A, 18A) on an upper active portion, the conveyor belt preferably being closed in a loop; preferably, the conveyor belts (17, 18) are inclined from bottom to top in the direction from the first and second accumulation stations (12, 13) to the formation area of the loop (T1).

5. A machine as claimed in one or more of claims 2 to 4, wherein it comprises a controller controlling the speed of at least one of the intermediate moving surfaces (17A, 18A) from opposite sides of the forming zone (19) of free loops, so that if the detection means (20) of the fabric loops detect the absence or presence of an excess of loops (T1) in the forming zone (19), the controller modifies the speed of at least one of the intermediate moving surfaces (17A, 18A) to recover the correct quantity of loops (T1) in the forming zone (19).

6. The machine according to one or more of claims 2 to 5, wherein the air distribution system (15) has an air ejector (21) facing the intermediate moving surface (17A, 18A) of the fabric and a facing suction duct (23) placed opposite the air ejector (21) with respect to the intermediate moving surface (17A, 18A), such that air is ejected from the air ejector (21) to pass through the fabric placed on the intermediate moving surface (17A, 18A) and is sucked by the suction duct (23); preferably, the air injector (21) is operatively connected to an air heating device (26); preferably, the air heating device (26) has an air intake duct (27) operatively connected to the environment surrounding the first and second accumulation stations (12, 13) such that at least a portion of the air heated by the air heating device (26) is extracted from the environment enclosed by the first and second accumulation stations (12, 13); preferably, the suction duct (23) is operatively connected to a suction fan (28) connected to the exhaust outlet flue (25) so that at least a portion of the air sucked is extracted from the environment enclosed by the first and second accumulation stations (12, 13).

7. The processor of claim 6, wherein the module has a fabric moisture sensor (29); preferably, the treatment machine comprises a controller controlling the amount and/or speed of air supplied towards the fabric and/or a controller controlling the heating temperature of the air supplied into the module (10A) based on the humidity value detected by the humidity sensor (29).

8. The machine according to one or more of the preceding claims, wherein said module (10A) comprises only two accumulation stations (12, 13), insertion means (30) for inserting the fabric into said first accumulation station (12) and extraction means (31) for extracting the fabric from said second accumulation station (13), both of which are suitable for moving the fabric with a same second movement speed by the movement of said support surfaces (17A, 18A) of the fabric, said second movement speed being lower than the first speed of the alternate movement of the fabric between said two accumulation stations (12, 13); preferably, the first speed of the alternating movement between the two accumulation stations (12, 13) is at least three times, and more particularly at least five times, and even more preferably between nine and eleven times the value of the second speed, preferably the first speed is eleven times greater than the value of the second speed.

9. The machine according to claim 8, wherein said insertion device (30) comprises an initial moving surface (30A) of said fabric, said fabric being adapted to be arranged on said initial moving surface; preferably, the insertion device (30) comprises a movement member defining the initial movement surface (30A), which moves the fabric towards the first accumulation station (12); preferably, the movement member is a conveyor belt defining the initial movement surface (30A) on the upper active portion, said conveyor belt preferably being closed in a loop, preferably inclined from top to bottom in the direction of insertion of the fabric.

10. A processor according to claim 8 or 9, wherein the extraction device (31) comprises a final moving surface (31A) of the fabric, the fabric being adapted to be arranged on the final moving surface; preferably, the extraction means comprise a movement member defining the final movement surface (31A) which moves the fabric from the second accumulation station (13) towards the outside of the module; preferably, the moving member is a conveyor belt defining the final moving surface (31A) on the upper active portion, said conveyor belt preferably being closed in a loop, preferably inclined from bottom to top in the extraction direction of the fabric.

11. A machine according to any one of claims 8, 9 or 10, comprising a plurality of said modules (10A) arranged in series with respect to each other, and wherein said fabric is adapted to move alternately in each module (10A) between said first and second accumulation stations (12, 13) at said first speed; -moving between the modules (10A) in a single direction of forward movement at the second speed lower than the first speed, so that the fabric as a whole passes through the treatment machine at the second speed.

12. A machine according to claim 11, wherein between successive modules (10A) the fabric is adapted to travel from the final moving surface (31A) of the module (10A) from which the fabric exits extraction means (31) to an initial moving surface (30A) of the module (10A) of the insertion means (30) into which the fabric enters, and wherein a further forming zone (119) of the free loop (T1 ') of fabric and a further detection means (120) of the loop of fabric in the further forming zone (119) are provided between the extraction means and the insertion means, such that during the movement of the fabric between the extraction means (30) and the insertion means (31) of two successive modules (10A), the fabric forms a free loop (T1') in the forming zone (119).

13. The machine according to claims 6 and 12, wherein the air distribution system (15) has a further air ejector (121) facing the initial and final moving surfaces (30A, 31A) of the fabric and a facing further air suction duct (123) placed opposite the further air ejector (121) with respect to the initial and final moving surfaces (30A, 31A) such that air is ejected from the further ejector (121) to pass through the fabric placed on the initial and final moving surfaces (30A, 31A) and is sucked by the further suction duct (123); preferably, the further air ejector (121) is operatively connected to the air heating device (26).

14. A handler according to claim 12 or 13, wherein the handler comprises a controller controlling the speed of at least one of the final and initial moving surfaces (30A, 31A) of the extraction and insertion devices (30, 31) of two adjacent modules (10A) such that if the further loop detection device (120) detects the absence or presence of an excess loop in the further forming region (119), the controller modifies the speed of at least one of the final and initial moving surfaces (30A, 31A) to restore the correct amount of loop in the further forming region (119).

15. The machine according to one or more of claims 11 to 14, wherein the distribution system (15) comprises a controller that controls the temperature of the air fed into each module (10A) so that in each module (10A) the air can be distributed onto the fabric at a desired temperature independently of the temperature of the air distributed in the other modules (10A).

16. A machine as claimed in one or more of the preceding claims, comprising means (40) for generating commands to reverse the movement of said fabric between said first and second accumulation stations (12, 13); preferably, said means (40) for generating commands to reverse the movement of said fabric between said first and second accumulation stations (12, 13) comprise: -means (41) for evaluating the amount of fabric in the first and second accumulation stations (12, 13), adapted to command the reversal of movement between the first and second accumulation stations (12, 13) when a given minimum value of accumulated fabric is reached; or means (42) for evaluating the tension of the fabric, the means for evaluating the tension of the fabric exiting from the first and second accumulation stations (12, 13) such that when a tension value equal to or greater than a threshold is reached, a reversal is commanded; or a combination of said means for assessing the amount of fabric in said first accumulation station and said second accumulation station and said means for assessing the tension of said fabric (42).

17. The machine according to one or more of the preceding claims, wherein each accumulation station (12, 13) comprises an accumulation tank (12A, 13A) to which a respective sensor (41) for evaluating the quantity of fabric provided in said accumulation tank is associated; preferably, the sensor is a sensor that senses the weight of the fabric accumulated in the accumulation groove.

18. A machine according to one or more of the preceding claims, comprising one or more of said modules (10A), means for inserting the fabric continuously into the first module from outside the machine, and means for extracting the fabric continuously from the last module, so that the machine processes the fabric continuously.

19. A machine as claimed in one or more of the preceding claims, wherein each of said modules (10A) defines a suitable treatment chamber (11) having an inlet for the continuous feed of the fabric and an outlet for the continuous extraction of the fabric.

20. A treatment method for shrinking and dimensionally stabilizing a fabric, wherein in at least one treatment chamber (11) the fabric is alternately accumulated in a first accumulation station (12) and a second accumulation station (13) by alternating forward and return movement of the fabric along a movement path (14) between the first and second accumulation stations (12, 13), and wherein during movement the fabric is impacted by an air flow, preferably hot, characterized in that along said movement path (14) the fabric is supported on two movement surfaces (17A, 18A) and is not supported in a free loop forming zone (19) defined between said movement surfaces (17A, 18A) thereof, such that during movement a free loop (T1) is formed by gravity in said forming zone (19).

21. A method according to claim 20, wherein during the movement of the fabric, the presence of free loops of the fabric between the moving surfaces (17A, 18A) is monitored.

22. A method according to claim 21, wherein if a lack or presence of excess free loops is detected in the forming zone (19), the speed of at least one of the moving surfaces (17A, 18A) is modified to recover the correct amount of loops in the forming zone (19).

23. Method according to one or more of claims 20, 21 and 22, wherein the humidity of the fabric in the chamber (11) is detected and, if this value is outside a given operating range, the amount and/or the speed of the air fed towards the fabric and/or the temperature of the air fed is modified.

24. The method according to one or more of claims 20 to 23, wherein the air heating the fabric is passed through the fabric arranged on the moving surface (17A, 18A) by suction from below the moving surface, such that the fabric arranged on the moving surface (17A, 18A) remains substantially stationary with respect to the moving surface during movement of the moving surface.

25. The method according to one or more of claims 19 to 24, wherein the reversal of the movement of the fabric between the accumulation stations (12, 13) occurs when the amount of accumulated fabric measured in the accumulation stations is equal to or below a threshold value or the tension of the fabric exiting from the accumulation stations is measured equal to or above a threshold value.

26. The method according to one or more of claims 19 to 25, wherein the fabric is continuously moved through one or more chambers (11), wherein the input speed of the fabric into the chambers and the output speed of the fabric out of the chambers are lower than the movement speed of the fabric between the first and second accumulation stations (12, 13) of each chamber (11); preferably, the speed of the alternating movement between the first and second accumulation stations (12, 13) is at least three times the input speed of the fabric into the chamber (11) and the output speed of the fabric out of the chamber, and more particularly at least five times the input speed of the fabric into the chamber (11) and the output speed of the fabric out of the chamber, and even more preferably between nine times and eleven times the value of the input speed of the fabric into the chamber (11) and the output speed of the fabric out of the chamber, preferably the speed of the alternating movement is greater than eleven times the value of the input speed of the fabric into the chamber (11) and the output speed of the fabric out of the chamber.

27. A method as claimed in claim 26, wherein the formation zone (119) of the free loop (T1') of the fabric is provided between two consecutive treatment chambers (11) and is defined between the moving surfaces (17A, 18A) of the fabric for extracting the fabric from the chambers and inserting the fabric into the chambers, respectively; preferably, the presence of free loops of the fabric between said moving surfaces (17 a,18 a) is monitored during the movement of the fabric; preferably, if the absence or presence of an excess of free loops in the forming region is detected, the speed of at least one of the moving surfaces is modified to recover the correct amount of loops in the forming region.

28. The method according to one or more of claims 20 to 25, which is adapted to process a single portion of fabric accumulated in the accumulation station (12, 13) during a working cycle, which means that fabric is treated discontinuously in the chamber (11), so that all fabric to be treated is inserted into the chamber and subsequently treated, and then extracted from the chamber (11).