MACHINE FOR CONTINUOUS WASHING OF FABRICS

Abstract

 A machine for continuous washing of fabric in rope form, comprising two or more wash tanks (11, 12), including an initial wash tank (11) in which the fabric (T) is designed to enter at a first speed (V1) and a final wash tank (12) from which the fabric is designed to exit at the same said first speed (V1), fabric being accumulable in said wash tanks. The machine also comprises means for alternate movement (19) of the fabric between at least two consecutive wash tanks (11, 12) with a second movement speed (V2), greater with respect to said first speed (V1), in such a manner as to alternately accumulate fabric in said two consecutive wash tanks (11, 12)..

Description

TECHNICAL FIELD

[0001] The present invention relates to the field of machines for continuous treatment of fabrics and more in particular to a machine for continuous washing of fabric in rope form.

State of the art

[0002] Machines for continuous washing of fabric are known. For the most part, these machines wash the fabric by means of a single passage of the fabric through wash baths in which it is subjected to hydrodynamic and mechanical actions designed to reduce impurities. However, the dwell times of the fabric in these baths are very short, as the dimensions of the machine for washing are limited and due to the fact that the advance speed of the fabric and therefore the productivity of the machine are favored with respect to the quality of the wash.

[0003] A machine for continuous washing that attempts to solve the problems linked to the short dwell times of the fabric in the wash baths is described in the United States patent US5623738 by the same applicant. This machine has at least two wash tanks through which the fabric is made to pass. In practice, the fabric is fed from outside to the first tank, where an accumulation of fabric is formed, and from which it is made to pass through a first conveying duct toward an area provided with a rotating reel; from this area, through a second conveying duct, the fabric is made to reach the second wash tank and from here is made to exit from the machine (in the case of only two tanks). The conveying ducts are ducts through which the fabric in rope form is made to pass and into which pressurized water is introduced with the same direction as the direction of advance, driving the fabric. The reel rotates in the same direction as movement of the fabric.

[0004] The entry speed from outside the machine to the first tank and the exit speed from the second tank to the outside the machine are substantially the same. The fabric is conveyed from the first tank to the second tank at a greater speed with respect to the speed of entry and exit from the machine, thereby forming an accumulation of fabric in the second tank. In this step the conveying water is introduced into the second conveying duct but not into the first duct, thus driving the fabric toward the second tank. Once the accumulation of fabric in the first tank has terminated and an equivalent accumulation has formed in the second tank, a three-way valve enables water to flow into the first conveying duct but not into the second, thus reversing the direction of movement of the fabric between the two tanks. In practice, the fabric is moved alternately from one tank to the other; added to this movement is the slower movement of advance along the whole of the machine, which corresponds to the treatment speed thereof.

[0005] Although this machine was designed many years ago, it has never found a true end market, as the effective wash performances have proved to be inferior to other types of wash machines with a simpler structure (even if these have lower productivity).

[0006] Another known machine, functioning in a similar manner, is for example described in the European patent EP0653508. In this machine, which treats fabric in open width and which does not perform wash but chemical impregnation treatments, a pneumatic system is used in combination with water flowing in the same direction through transport nozzles. This machine also describes a system of sensors designed to detect termination of the accumulation in a tank and to control reversal of the movement of the fabric. In particular, this system of sensors provides, for each tank, a vertical rod (protected by a respective guide structure) slidingly hung in the center of the respective tank. The fabric in each tank extends in a "U", i.e. from the top (entry into the tank) downward (accumulation) and then upward again (exit from the tank). When the accumulation of fabric in a tank has terminated, the fabric is lifted from the bottom thereof as a result of being driven by the pneumatic system and the lowest part thereof (the bottom of the "U") touches the end to the rod, lifting it. Movement of the rod activates a switch that controls reversal of the movement of the fabric, i.e. reversal of the direction of the pneumatic air flows, blocking of the water in one transport nozzle and introduction of water into the other transport nozzle, in the same direction as movement of the fabric. This system of sensors is somewhat inconvenient and causes impacts and sticking of the fabric during movement, with the risk of damaging it. This machine is not suitable for wash functions, in particular for fabric in rope form.

Object and summary of the invention

[0007] The object of the present invention is to solve the problems of machines for continuous washing of fabrics present in known machines.

[0008] Within the object set forth above, another important object of the present invention is to develop a machine for washing, and also a method for washing, which has improved efficacy of the wash with respect to known machines for washing.

[0009] A further important object of the present invention is to produce a machine for washing having high productivity.

[0010] One more object of the present invention is to produce a machine for washing that reduces the risks of damage for the fabric.

[0011] These and other objects, which will be more apparent below, are achieved with a machine according to claim 1, i.e. a machine for continuous washing of fabric in rope form, which comprises two or more wash tanks, including an initial wash tank in which the fabric is designed to enter at a first speed and a final wash tank from which the fabric is designed to exit at the same said first speed, fabric being accumulable in said wash tanks, said machine also comprising means for alternate movement of the fabric between at least two consecutive wash tanks with a second movement speed, greater with respect to said first speed, in such a manner as to alternately accumulate fabric in said two consecutive wash tanks, there being present at least one transit duct through which the fabric is designed to pass during passage inside the machine and along which the wash water is designed to flow; characteristically, there are present means designed to make water flow through at least one said transit duct in the opposite direction to the direction of movement of the fabric when it passes through the same duct. In practice, a flow of water in the opposite direction to advance of the fabric in the same transit duct is obtained, causing an effective washing action.

[0012] According to a preferred embodiment of the invention, there are provided a transit duct for fabric entering a respective wash tank and/or a transit duct for fabric exiting from a respective wash tank, wherein said transit duct for entering and/or exiting is provided with a discharge port open onto a respective wash tank below; the wash water is made to flow toward this port.

[0013] In accordance with some preferred embodiments of the invention, each wash tank is provided with a transit duct for entering fabric and a transit duct for fabric exiting, wherein the wash water flows toward said wash tank.

[0014] According to some preferred embodiments of the invention, the machine is provided with a base module which comprises two wash tanks, a first tank in which fabric enters at said first speed, a second tank from which fabric exits at said first speed and between which there are provided said means for alternate movement of the fabric between the two first and second tanks passing through respective transit ducts; in practice, there is provided a transit duct of fabric exiting from the first tank and a transit duct entering the second tank when the fabric is moved in a first direction; when the direction of movement is reversed, the transit duct exiting from the first tank becomes the duct for entering the first tank and analogously the duct for entering the second tank become the duct for exiting from said second tank.

[0015] With reference to this last case, with a machine according to the invention, comprising a single base module, i.e. formed by only two wash tanks, the initial wash tank corresponds to the first tank of the aforesaid base module, and the final wash tank corresponds to the second wash tank of the base module.

[0016] In the case of several base modules in series with one another, the aforesaid means for alternate movement are preferably arranged only between the wash tanks of the respective base modules, while between one base module and the other there are provided means for extracting the fabric from a second tank and for introducing the fabric into the subsequent first tank of the following base module.

[0017] In practice, with a machine formed by one or more base modules, an even number of the tanks are always provided. In other embodiments, an odd number of the tanks can also be provided, for example using three consecutive tanks through which the fabric moves alternately at high speed (i.e. the second speed). Therefore, in other embodiments, a base module can have three wash tanks.

[0018] According to some preferred embodiments, each wash tank is provided with a transit duct for entering fabric and a transit duct for fabric exiting; through said fabric exiting/entering transit ducts the wash water flows toward said each wash tank, and wherein said hydraulic means flowing the water through said two transit ducts act in a substantially simultaneous manner.

[0019] According to some preferred embodiments, said means designed to make the water flow through the transit duct which discharge into a same wash tank act in a substantially simultaneous manner.

[0020] With reference to some preferred embodiments of the invention, the hydraulic means flowing the water through the transit ducts exiting from the first tank and entering the second tank, act in a substantially simultaneous manner, so that during alternate movement of the fabric between said first and second tank through said transit ducts, the water flows through the same transit ducts toward the discharge into the tanks below, so that, alternately, the fabric passes through each duct in one direction with the water flowing in the same direction as the fabric or the fabric passes through it in the opposite direction, while the water continues to flow in the same direction and therefore flows in the opposite direction to the fabric, obtaining an effective washing action. Moreover, in this case, there is also balancing between the tensile force generated on the fabric by the water that flows in the same direction as the same fabric and the opposing force generated on the fabric by the water flowing in the opposite direction.

[0021] Preferably, in the case of a base module, the fabric passes through the transit duct entering the first tank always in the same direction as the flow of water flowing therethrough, while the fabric passes through the transit duct exiting from the second tank always in the opposite direction to the flow of water flowing through the duct.

[0022] According to some preferred embodiments, at least one said transit duct comprises pivoting means for rotation of the transit duct, for a given angular travel, over a wash tank; there being associated with said pivoted transit duct sensor means and/or a switch such that a control signal directed to the means for alternate movement of the fabric corresponds to a predetermined angular position of the transit duct along said angular travel, said control signal controls reversal of the direction of movement of the fabric, wherein rotation of the transit duct occurring through thrust of the fabric on said transit duct during lifting of the fabric passing through the wash tank when accumulation in said tank has terminated.

[0023] According to some preferred embodiments, the machine comprises a transit duct for fabric entering a respective wash tank and/or a transit duct for fabric exiting from a respective wash tank, wherein said transit duct for entering and/or exiting is provided with a discharge port open onto a respective wash tank below; the wash water being made to flow toward this port, and wherein said at least one said transit ducts is pivoted in such a manner as to be able to rotate, for a given angular travel, about an axis incident with the plane of the trajectory of the fabric in the respective wash tank in which the transit duct is arranged.

[0024] The pivoting means of the transit duct are formed by a rotation or oscillation axis about which the transit duct is obliged to rotate or oscillate.

[0025] It is clear that the invention is based on the possibility of at least one transit duct for a wash tank (and more in particular, of the discharge port of said transit duct), being pivoted, to rotate along an arc of circumference from a starting position, corresponding to a phase of the machine work wherein the fabric is accumulated, to a rotated position by means of the thrust of the fabric on the pivoted transit duct when the accumulation is terminated. The rotation provokes a signal controlling the reversal of the movement of the fabric in the tank.

[0026] Therefore the transit duct is pivoted in such a manner to rotate about an axis such that the transit duct rotates. To perform such rotation, the axis can be variously oriented. Every orientation of the axis performing said rotation can be considered equivalent one to the other.

[0027] Preferably, the pivoted transit ducts is pivoted in such a manner to rotate, for a given angular travel, with an bottom-up movement and vice-versa.

[0028] Advantageously, according to some preferred embodiments, in the case of a machine formed by one or more base modules comprising two wash tanks according to one or more of the embodiments set forth above, at least one base module is provided with a said first wash tank equipped with a single said transit duct of rotating type arranged at the inlet of the first tank to control reversal of the means for alternate movement between said first tank and the subsequent second wash tank; there being provided in the same base module a single said transit duct of rotating type arranged at the outlet of the second tank to control reversal of said means for alternate movement between said first tank and said subsequent second wash tank of the same module.

[0029] According to some preferred embodiments of the invention, the means for alternate movement of the fabric between two wash tanks comprise a rotating driving member, preferably arranged above the outlets of transit ducts of the fabric exiting and entering the two tanks in which the fabric is moved in alternate manner.

[0030] According to some preferred embodiments, the transit duct of rotating type comprises a fixed part and a rotating part pivoted to said fixed part and arranged below it; preferably both these parts comprise a tubular body through which the fabric and the wash water pass; more preferably, the fixed part is provided with a tubular portion inserted inside the tubular body of the rotating part; preferably, the discharge port of the water and of the fabric from the rotating transit duct is provided at the end of the tubular body of the rotating part.

[0031] Preferably, the tubular body of the rotating part is an extension of the tubular body of the fixed part, which can oscillate between two positions about its rotation axis.

[0032] According to some preferred embodiments, the angular travel of the tubular body of the rotating part is limited between a first position with said tubular body substantially vertical, i.e. coaxial with the tubular portion of the fixed part, to a second inclined position, in which its axis of development is oriented downward and toward the center of the respective wash tank.

[0033] According to some embodiments, there are provided means for adjusting the width of the angular travel of the rotating part of the rotating transit duct, for example comprising one or more limit stops fixed to the fixed part and/or to the moving part, the position of which is adjustable to vary the travel.

[0034] In accordance with some preferred embodiments, there are provided means to return the rotating part of the rotating conveying duct to the start of travel position when stressed to rotate toward the end of travel position.

[0035] According to some embodiments, the sensor means associated with the rotating conveying duct which have the function of indicating when rotating part of the transit duct starts to rotate or reaches, starting from its first position, a certain angular position, comprise a first element preferably constituted by a magnetic sensor fixed to the fixed part of the transit duct and a second element preferably formed by a magnet functionally coupled to the magnetic sensor and which is constrained to the rotating part of the rotating conveying duct; with the rotating part arranged in the initial position, preferably vertical, the magnet is spaced from the sensitive part of the magnetic sensor; when the rotating part starts to rotate, the magnet starts to move toward the magnetic sensor until it enters it "range of action" with consequent detection of the movement and sends a signal to the means for alternate movement in order to reverse the movement of the fabric.

[0036] In accordance with some preferred embodiments, there are provided means to adjust the sensitivity of the sensor means. With reference to the case set forth above, for example these means to adjust the sensitivity comprise means to adjust the relative distance between magnetic sensor and magnet, for example to move these elements toward each other in such a manner that detection of rotation occurs in a shorter time or to move them away from each other to obtain a longer reaction time.

[0037] According to some preferred embodiments of the invention, there are provided means for introducing the fabric into the initial wash tank.

[0038] In accordance with some preferred embodiments of the invention, there are provided means for extracting the fabric from the final wash tank.

[0039] In some embodiments, the fabric can be introduced and extracted from the machine using means belonging to machinery that precedes or succeeds the machine according to the invention and therefore is not directly integrated therewith. In a preferred embodiment of the invention, the means for introducing and extracting the fabric from the machine are integrated therein.

[0040] According to another aspect, the invention also relates to a machine for continuous washing of fabric in rope form, which comprises two or more wash tanks, including an initial wash tank in which the fabric is designed to enter at a first speed and a final wash tank from which the fabric is designed to exit at the same said first speed, fabric being accumulable in said wash tanks, said machine also comprising means for alternate movement of the fabric between at least two consecutive wash tanks with a second movement speed, greater with respect to said first speed, in such a manner as to alternately accumulate fabric in said two consecutive wash tanks, there being present at least one transit duct through which the fabric is designed to pass during passage inside the machine and along which the wash water is designed to flow; characteristically, there are present hydraulic means flowing the wash water through at least one said transit duct in the opposite direction to the direction of movement of the fabric when it passes through the same duct. In practice, said hydraulic means are means designed to make water flow through at least one said transit duct in the opposite direction to the direction of movement of the fabric when it passes through the same duct, i.e.a flow of water in the opposite direction to advance of the fabric in the same transit duct is obtained, causing an effective washing action.

[0041] This aspect of the invention can be combined with one or more of the embodiments of the aspect of the invention presented above when not directly dependent on its main characteristic, i.e. the fact that the machine is provided with the "rotating transit duct" concept. Therefore, according to a particularly advantageous embodiment, said at least two wash tanks are provided with at least one said transit duct which is pivoted in such a manner as to be able to rotate, for a given angular travel, about an axis, preferably incident with the plane of the trajectory of the fabric in the respective wash tank in which the transit duct is arranged; there are associated with said at least one transit duct sensor means and/or a switch such that a signal to control the means for alternate movement of the fabric between said two tanks, designed to control reversal of the direction of movement of the fabric, corresponds to a predetermined angular position of the transit duct; rotation of the duct occurs through thrust of the fabric on the duct during lifting of the fabric passing through the wash tank when accumulation in said tank has terminated; in practice, rotation of the duct signals that the fabric accumulated has terminated and therefore the direction of movement of the fabric must be reversed.

[0042] According to another aspect, the invention also relates to a method for continuous washing of fabric in rope form which provides for accumulating fabric in a first wash tank, moving in an alternate manner from said first wash tank to a second wash tank and vice versa with a movement speed and, preferably simultaneously to the alternate movement, feeding fabric into said first tank and removing fabric from said second tank with a speed lower than the alternate movement speed; characteristically, the method provides for making the fabric pass through a flow of water with direction approximately opposite to the direction in which the fabric is moved.

[0043] According to a preferred embodiment, a step of making the fabric pass through a flow of water with direction approximately opposite to the direction in which the fabric is moved occurs during the step of alternate movement of the fabric.

[0044] According to a preferred embodiment, a step of making the fabric pass through a flow of water with direction approximately opposite to the direction in which the fabric is moved occurs during exit from the second wash tank.

[0045] Advantageously, in the preferred embodiment, the step of making the fabric pass through a flow of water with opposite direction occurs with the water flowing from the top downward and the fabric moved from the bottom upward, preferably according to a substantially vertical direction.

[0046] The "rotating" configuration of the transit duct that acts as control for reversal of the alternate movement of the fabric is particularly synergic with the case of movement of the fabric in a flow of wash water that moves in the opposite direction: in fact, the opposite movement of the fabric with respect to the water, as said, enables balancing of the force exerted by the water in the ducts and the alternate movement of the fabric is left only to the means for alternate movement. These means for alternate movement can impart very "aggressive" pulling effects on the fabric, and therefore the "rotating inertia" of the duct and the related travel before activation of reversal enables a reduction of any excessive pulling action on the fabric. Moreover, the rotating part of the transit duct can substantially form an extension that enables increase of the extent of "back-washing" of the fabric that passes through the same duct in the opposite direction to the wash water.

[0047] In any case, it must be noted that the idea of the rotating conveying duct that enables control of the means for alternate movement to reverse the direction of the fabric between the tanks is also advantageous for known machines, such as those indicated previously, i.e. machines in which there is reversal of the movement of the fabric between consecutive tanks with the fabric passing through transit ducts without the water in said duct flowing in the opposite direction to advance of the fabric in the same ducts. In fact, with the rotating duct it is possible to control reversal, reducing the risk of the fabric sticking inside the machine with respect to other types of known sensors, and also to vacate greater space in the tanks with respect to known sensors, enabling improved carrying capacity and simpler construction.

[0048] Another aspect of the invention also relates to a machine for continuous washing of fabric in rope form, which comprises two or more wash tanks, including an initial wash tank in which the fabric is designed to enter at a first speed and a final wash tank from which the fabric is designed to exit at the same said first speed, fabric being accumulable in said wash tanks; said machine also comprises means for alternate movement of the fabric between at least two consecutive wash tanks with a second movement speed, greater with respect to said first speed, in such a manner as to alternatively accumulate fabric in said two consecutive wash tanks, there being present at least one duct through which the fabric is designed to pass during passage inside the machine and along which the wash water is designed to flow; characteristically, at least two consecutive wash tanks have at least one said transit duct which is pivoted in such a manner as to be able to rotate, for a given angular travel, about an axis, preferably orthogonal, incident with the plane of the trajectory of the fabric in the respective wash tank in which the duct is arranged; there are associated with said transit duct sensor means and/or a switch such that a signal to control the means for alternate movement of the fabric between said two tanks, designed to control reversal of the direction of movement of the fabric, corresponds to a predetermined angular position of the duct; rotation of the duct occurs through thrust of the fabric on the duct during lifting of the fabric passing through the wash tank when accumulation in said tank has terminated; in practice rotation of the duct signals that the fabric accumulated has terminated and therefore the direction of movement of the fabric must be reversed.

Brief description of the drawings

[0049] Further characteristics and advantages of the invention will be more apparent from the description of a preferred but non-exclusive embodiment thereof, illustrated by way of non-limiting example in the accompanying drawings, wherein:

Fig. 1 represents a schematic front view of a base module of a machine according to the invention;

Fig. 2 represents a schematic axonometric view of a machine according to the invention, with some parts removed to show the inside thereof; composed of two modules of Fig. 1;

Fig. 3 represents a schematic front view of a transit duct for the fabric;

Fig. 4 represents a schematic side view of the duct of Fig. 3;

Fig. 5 represents a detail of Fig. 3, varied with respect thereto.

Detailed description of an embodiment of the invention

[0050] With reference to the aforesaid figures, a base module of a machine for washing fabric in rope form is indicated as a whole with the number 10, while a machine formed by two base modules in series is indicated as a whole with 100.

[0051] With reference to Fig. 1, the base module 10 is provided with two tanks, a first tank 11 for entry of the fabric into the module 10, and a consecutive second tank 12 for exit of the fabric from the module, arranged at a greater height to the first tank, i.e. provided with a discharge outlet 12A which is higher with respect to the loading inlet 11 A of the first tank 11.

[0052] Above the first tank 11, there are provided means 13 for introducing the fabric in rope form T into the first tank 11. These means 13 comprise, in this example, a first motorized driving member 14, rotating, such as a drum on which the fabric is made to adhere by means of a roller 15 that pushes the fabric onto the cylindrical surface of the drum. Above the second tank 12 there are provided means 16 for extracting the fabric from the second tank; analogously to the previous case, these means 16 comprise, in this example, a second motorized driving drum 17, rotating, on which the fabric is made to adhere by means of a roller 18 that pushes the fabric onto the cylindrical surface of the same drum.

[0053] The base module can as a whole form a machine with only two tanks, in which case the first tank 11 is an initial wash tank and the second tank 12 is a final wash tank for the fabric in rope form.

[0054] Each module of the machine (i.e. a machine formed by one base module or combinations in series thereof) is provided with means for alternate movement 19 of the fabric from the first tank 11 to the second tank 12 and vice versa. In this example, these means for alternate movement 19 advantageously comprise an intermediate driving member 20, rotating, motorized, substantially analogous to the first and to the second drum 14 and 17, on which the fabric is made to adhere by means of a related roller 21 that pushes the fabric onto the cylindrical surface of the same intermediate drum. In practice, according to the direction of rotation of the intermediate drum 20, the fabric in rope form T is moved from the first tank 11 to the second tank 12 or vice versa. In these examples, the motors of the rotating drums are indicated with M.

[0055] It should be noted that the input speed V1 (also defined "first speed") of the fabric T into and the output speed from, the machine 10 or 100, is substantially the same, i.e. the same amount of fabric enters and exits from the machine in the same unit of time.

[0056] Differently, the movement speed V2 between the first tank 11 and the second tank 12 (also defined "second speed" of the fabric) and vice versa, is much greater with respect to the speed V1 for introducing or extracting the fabric from the machine (or from the second tank into the first subsequent tank in the case of several modules in series). For example, the first speed V1 of the fabric entering or exiting from the machine is in the order of 10 m/s, while the speed of alternate movement between the tanks is, for example, in the order of 100, 200, or 300 m/s.

[0057] It should be noted that the fabric in rope form T moves substantially along a trajectory that is approximately lying on a single longitudinal plane, in this example advantageously vertical, which passes through the whole of the machine.

[0058] In the base module there are provided two transit ducts for the fabric for each tank, and in particular a first transit duct 22 for entry of the fabric in the first tank 11, a second transit duct 23 for exiting from first tank, a third transit duct 24 for entering the second tank 12 and a fourth transit duct 25 for exiting from the second tank 12.

[0059] As is clearly visible from the figures, in this example the second and third transit duct 23 and 24 are arranged below the means for alternate movement 19, and in particular arranged from the top downward, preferably with axis substantially vertical; more in particular, in this example they are advantageously arranged substantially aligned respectively with two opposite tangents vertical to the driving drum 20 which are close to the trajectory for attachment and detachment of the fabric from the same drum 20.

[0060] Analogously, the first transit duct 22 is preferably arranged below the means 13 for introducing the fabric into the first tank 11, and in particular arranged from the top downward, and a fixed part thereof 22A, as will be explained in more detail hereunder, is preferably arranged with axis substantially vertical; more in particular, in this example this fixed part 22A is advantageously arranged substantially aligned with the tangent vertical to the driving drum 14 which is close to the trajectory for detachment of the fabric from the same drum 14.

[0061] Analogously, the fourth transit duct 25 is preferably arranged below the means 16 for extracting the fabric from the second tank 12, and in particular arranged from the top downward, and a fixed part thereof 25A, as will be explained in more detail hereunder, is preferably arranged with axis substantially vertical; more in detail, in this example this fixed part 25A is advantageously arranged substantially aligned with the tangent vertical to the driving drum 17 which is close to the trajectory for attachment of the fabric to the same drum 17.

[0062] Each transit duct 22, 23, 24 and 25 of the fabric T is hydraulically connected to hydraulic means designed to distribute wash water inside the same ducts. In Fig. 1 these hydraulic means have been omitted to simplify the drawing, but are represented in the machine of Fig. 2 formed by two base modules 10' and 10 in series with each other. For the description of these hydraulic means, indicated here with 26, particular reference should be made to the second base module 10, but the same concepts and elements are substantially found in the first base module 10' of the same Fig. 2 and are intended also to be present in the base module 10 of Fig. 1. It should be noted that the same elements of the base module 10 of the machine of Fig. 2 are indicated with the prime symbol' in the base module 10' of the same machine.

[0063] In this example, introduction of the water into the transit ducts is such that the water always flows downward. Preferably, each transit duct 24 and 25 is reached by a pipe, described hereunder, which connects to an inlet 27 defined on the side of the same transit duct; this inlet 27 is shaped in such a manner that the water is obliged to enter the transit duct and flow downward to the discharge port of the transit duct open over the respective wash tank. In the preferred embodiment described here, the hydraulic means 26 provide for each wash tank 11 and 12, respective pumps 28, each drawing from the corresponding tank. Associated with each pump is a respective filter 29 and the aforesaid delivery pipe 30 which branches into two sections 30A and 30B, each designed to feed a respective transit duct which discharges into the common wash tank below from which the respective pump 28 drew the water (with reference to the base module 10 of Fig. 2, the ducts 24 and 25 discharge into the tank 12 below and are fed by the common pump 28 which draws from the same tank 12).

[0064] As already mentioned, for example with reference to Fig. 2, the wash tanks of the machine are arranged in series at an increasing height, with the initial wash tank 11' at the lowest height, and are hydraulically connected to one another so that water flows from the final wash tank 12 (the tank at the greatest height) by gravity toward the adjacent wash tank at a lower height 11 and so forth until reaching the initial wash tank 11'.

[0065] Advantageously, the water that flows into the final wash tank 12 (i.e. at the greatest height) is clean water, while the water that flows into the tanks below the final tank 12 becomes dirty due to the washes. In practice, the fabric is washed continuously with increasingly clean water as it advances through the machine.

[0066] It should be noted that each wash tank 11 or 12 has an intermediate grille 11 B or 12B on which the fabric T, immersed in the wash water, is accumulated. Underneath the grille 11B-12B, there are provided means to heat the water 11C-12C (for example electric heating coils), in such a manner as to maintain the wash water at the required temperature.

[0067] The transit ducts 22, 23, 24, 25 (and equivalently the ducts 22', 23', 24', 25') comprise a part 23A (hereinafter reference is made to the duct 23, but the literal references of its components is the same also for the corresponding elements of the other transit ducts) fixed to the ceiling of the respective wash tank. This fixed part is provided with a tubular body 23B along which the fabric in rope form T travels. The tubular body 23B is surrounded by a sleeve 23C which forms therewith a hollow space 23D. It should be noted that the lower end portion 23W of the tubular body 23B projects downward with respect to the sleeve 23C. A respective section of pipe 30B which carries the wash water from the pumping means 26 leads into this sleeve 23C. The tubular body 23A is provided with a lateral opening 23E, preferably annular, i.e. developing all around the tubular body and having a trend converging in the direction of flow of the wash water i.e. converging toward the inside of the tubular body and downward. The pressurized water that enters the sleeve 23C is obliged to enter the tubular body 23A with downward direction. The delivery end of the pipe in the sleeve, the hollow space and the lateral opening 23E in practice define the inlet 27 of the pipe 30B to the transit duct 23. At the lower end of the transit duct 23, i.e. in this example at the lower end of the tubular body 23A, there is provided the port 23K for discharge of the water into the wash tank below, which also corresponds to the port through which the fabric in rope form T is designed to pass.

[0068] Advantageously, in a preferred embodiment described here, each wash tank has an indicator to indicate the end of accumulation of the fabric T in the respective tank. In particular, this indicator comprises a transit duct (22 if referred to the first tank 11; 25 if referred to the second tank 12) which is pivoted with respect to the structure of the machine in such a manner as to be able to rotate, for a given angular travel, about an axis incident (preferably orthogonal) to the plane of the trajectory of movement of the fabric in the respective wash tank, i.e. the plane corresponding to the trajectory of the fabric through the whole of the machine, in which the duct is arranged. Particular reference should be made to Figs. 3, 4 and 5. In practice, considering the developing axes of the transit ducts, in this embodiment, all these developing axes lay on a common vertical plane.

[0069] As known, the term "incident" defines the orientation e.g. of a straight line with respect to a plane. The angle of incidence of the straight line on the plane can be 0°, if the straight line is parallel to the plane, or can be 90° if the straight line is orthogonal to the plane. Considering all other angles, the straight line is inclined with respect to the plane.

[0070] Obviously, in other embodiments, the transit ducts can be arranged in different planes, inclined (not vertical) or not inclined (different planes parallel each other); as an example, the pivoted transit ducts 22, 25 can lay on a same plane, while the fixed transit ducts 23, 24 can lay on another plane, parallel to the plane of the pivoted transit ducts.

[0071] Moreover, in other embodiments, the transit ducts can be arranged on horizontal planes and the rotation of the pivoted transit duct can be about a vertical axis.

[0072] Advantageously, sensor means 31 are associated with this rotating transit duct 22-25 (see in particular Figs. 3 to 5 in which one transit duct 22 is shown, although the same references also apply to the duct 25) such that a signal to control the means for alternate movement 19 of the fabric between the two wash tanks 11 and 12, designed to control reversal of the movement of the drum and therefore of the fabric, corresponds to a predetermined angular position of the transit duct 22-25 about the axis X. As will be explained in more detail hereunder, rotation of the transit duct occurs through thrust of the fabric T on the transit duct 22-25 during lifting of the fabric passing through the wash tank 11-12 when accumulation in the tank has terminated; in practice, rotation of the duct signals that the fabric accumulated in the tank below has terminated and therefore the direction of movement of the fabric must be reversed.

[0073] In general, the trajectory of movement of the fabric in the respective wash tank, is defined by the relative position of the pivoted transit duct 22 (25) and fixed transit duct 23 (24). As a matter of fact, since the fabric is in rope form and exit from and enter in the transit ducts that are over a respective wash tank, the rope fabric is subject to the gravity force and it is obliged to take a curved development, that substantially lays, for its most part, on a vertical plane (the ends of the curved development can be out of the plane, depending on the orientation of the development axes of the transit ducts or on the orientation of the ports of the transit ducts).

[0074] With reference to the transit duct of rotating type 22 (although this is the same for the transit ducts 25' and 25, with the same parts which will have the same numbers) this comprises a fixed part 22A as described above for the transit duct 23, and a rotating part 22F pivoted according to the axis X to this fixed part. In this example, the rotating part 22F is pivoted to the lower end portion 22W of the tubular body 22B and comprises a second tubular body 22G preferably of greater diameter with respect to the diameter of the first tubular body 22B in such as manner that the lower end portion 22W of the tubular body 22B is inserted inside the second tubular body 22G. This second tubular body 22G is pivoted according to X to the lower end portion 22W. In practice, the fixed parts 22A, 23A, 24A, 25A are substantially the same as one another while the rotating ducts 22 (and 25) have in addition a second tubular body 22G which is an extension of the first tubular body 22B, which can oscillate between two positions about the axis X. At the lower end of the transit duct 22, i.e. in this example at the lower end of the second tubular body 22G, there is provided the port 22K for discharge of the water into the wash tank below, and also the port through which the fabric in rope form T is designed to pass. It should be noted that no hydraulic seal is necessary between the first and the second tubular body, as the pressurized water is free to vent downward.

[0075] The angular travel G of the second tubular body 22G in this example is limited between a first position with the second tubular body substantially vertical, i.e. coaxial with the first tubular body 22B, to a second inclined position, in which its axis Y of development is oriented downward and toward the center of the respective wash tank. In this example, the limit stop for the first position is adjustable, and comprises for example a shock absorption pad 22H, for example with locating head in elastomeric material, the position of which parallel to the axis Y can be adjusted for example by means of a threaded coupling, which locates against the bottom of the sleeve 22C. Therefore, in this example, the first position, on the basis of the axial position or height of the pad 22H, can assume a plurality of arrangements comprised between a vertical position (in which the pad is completely lowered) and one or more inclined positions, in which the pad is elongated upward, abutting more rapidly against the bottom of the sleeve 22C. A graduated scale 22L is advantageously provided on the sleeve 22C, associated with which is an inclination indicator 22M fixed to the second rotating tubular body 22G.

[0076] In this example, the second position is defined by a fixed limit stop, for example produced by the upper edge 22N of the second tubular body 22G which is undercut by means of an inclined surface that allows this latter to rotate upward without interfering, until it locates, with the bottom of the sleeve 22C.

[0077] There is provided an element 22P for return of the rotating part 22F to the first position when stressed to rotate toward the second position, such as a spring fixed at the ends thereof to the fixed part 22A and to the rotating part 22F, in a suitably calibrated manner, the function of which is to prevent sudden lifting of the rotating part when thrust by the fabric.

[0078] There are associated with the transit duct 22 sensor means which have the function of indicating when the rotating part of the transit duct starts to rotate or reaches, starting from its first position, a certain angular position. From a practical point of view, the start of rotation of the rotating part 22F corresponds to the moment in which there is no longer any fabric accumulated in the wash tank below, as described in greater detail hereunder, and therefore rotation indicates the moment in which movement of the means for alternate movement 19 must be reversed.

[0079] The sensor means comprise, in this example, a first element preferably constituted by a rod-shaped magnetic sensor 22Q fixed to the fixed part 22A of the transit duct 22, and preferably to the sleeve 22C; this sensor 22Q is operative connected with electronic means (not indicated) associated with the means for alternate movement 19, i.e. with the electric motor of the rotating drum 20.

[0080] The aforesaid sensor means are provided with a second element preferably constituted by a magnet 22R which is functionally coupled to the magnetic sensor 22Q and which is fixed on a rod 22T constrained to the rotating part 22F of the transit duct 22. With the rotating part arranged in the first position, i.e. the second tubular duct 22G vertical, the magnet 22R is spaced from the sensitive part (in this example the tip) of the magnetic sensor 22Q. When the second tubular duct 22G starts to rotate, the magnet 22R starts to move toward the magnetic sensor 22Q until it enters its "range of action" (position indicated by a dashed line in Fig. 3) with consequent detection of the movement and sending of a signal to the means for alternate movement 19 in order to reverse the movement of the fabric.

[0081] According to the type of fabric and to the speed at which operation is to take place, the "sensitivity" of the sensor means can be adjusted. In this example the relative distance between magnetic sensor 22Q and magnet 22R can be modified, for example to move these elements toward each other so that detection of rotation takes place in a shorter time (or to move them away from each other to obtain a longer reaction time). It should be noted that the time that elapses between sending the signal to the means for movement and the moment in which the fabric starts to move in the opposite direction is not instantaneous, therefore adjustment of the distance between magnetic sensor and magnet can be useful also to prevent the second tubular duct 22G from reaching the upper limit stop before reversal, impacting and transmitting a certain additional violent pulling action on the fabric in the area of exit from the second tubular duct 22G. Fig. 5 shows, for example, one adjustment method. In practice, in this example, the rod 22T can be rotated (and subsequently blocked) on a pin coaxial with the axis of rotation X of the second tubular duct 22G, moving the magnet 22R along an arc of circumference close to the magnetic sensor 22Q. It goes without saying that sensor and magnet can be reversed, i.e. associated respectively with the rotating part and with the fixed part. Naturally, the type of sensor means and the method of applying them to the transit ducts of rotating type can vary widely.

[0082] It should be noted that in Fig. 2, in which the machine 100 is formed by two modules 10' and 10 placed in series, the means for introducing the fabric in rope form T into the initial wash tank 11' related to entry into the machine 100 are not visible and do not comprise a drum with pressure roller; for example, these means can comprise a conduit (not indicated) with a flow of pressurized water that pushes the fabric passing therethrough in the same direction. This conduit is, for example, hydraulically connected to the section of delivery pipe 30' of the pumping means 26' which draw wash water from the same initial tank 11'. It should be noted that with reference to this initial tank, the corresponding rotating conveying duct related to entry to the tank 22' is shaped in a slightly different manner with respect to those described previously. In fact, in this example the fixed part of the transit duct is not visible, only the rotating part 22F' being visible, i.e. the second tubular body 22G', pivoted according to an axis horizontal to the lateral wall (or to the fixed part of the duct not visible) to this fixed part. In this example, this second tubular body 22G' is shaped according to a 90° bend, with the discharge port 22K' facing downward.

[0083] Again in Fig. 2, the means 16 for extracting the fabric from the second tank 12 related to exit of the fabric from the machine comprise a pair of driving cylinders 32, motorized, between which the fabric is made to pass.

[0084] Operation of the machine is illustrated with particular reference to Fig. 2.

[0085] In the initial step, the fabric in rope form is introduced into the first base module 10' with passage through the first transit duct 22', of rotating type ( in this example curved in shape) and is then made to pass through the second transit duct 23', of fixed type, thus making it exit from the area of the first tank 11' and carrying it onto the rotating drum 20' of the means for alternate movement, with the respective pressure roller 21' which presses on the fabric to maintain it in contact with the drum and ensure traction. From the rotating drum 20', the fabric is made to pass through the third transit duct 24', of fixed type, thus making it enter the second wash tank 12'. From here the fabric is made to pass through the fourth duct 25' and made to exit from the area of the second wash tank 12' toward the second base module 10, passing over the rotating drum 17' (and related roller 18') forming the means 16' for extracting the fabric from base module 10' or also the means 13 for introducing the fabric into the same base module 10 (in this example, the means 16' coincide with the means 13). Passage of the fabric through the second base module 10 is analogous to that described above for the first base module 10'. The means 16 for extraction from the machine are, in this case, constituted by the pair of driving cylinders 32.

[0086] Once the initial part of the long rope of fabric has been made to pass through the machine, the same part of fabric in the machine is adapted in such a manner as to form accumulations of fabric in the initial wash tank 11' of the first base module 10' and in the first tank 11 of the second base module 10. The accumulations of fabric are soaked in the wash water.

[0087] At this point movement of the fabric is activated. The means for alternate movement 19' of the first module 10' carry with speed V2 the fabric accumulated in the first tank 11' into the second tank 12' and it is accumulated therein; simultaneously, also the means 19 for movement of the second base module 10 carry with speed V2 the fabric accumulated in the first tank 11 into the second tank 12 with related accumulation.

[0088] When the fabric accumulated in the first tank 11' has terminated and therefore an equivalent accumulation has formed in the second tank 12' (this movement is represented in Figs. 1 and 2), the means for alternate movement 19' reverse the movement of the fabric, starting to return the fabric now accumulated in the tank 12', to the tank 11', forming a new accumulation therein. The same occurs for the first and second tank 11 and 12 of the second module 10.

[0089] Control of reversal of the movement is given by the movement of the transit ducts of rotating type 22', 25' and 22, 25. In practice, once the accumulation of fabric has terminated in one tank, the same fabric, moved at the speed V2, is lifted from the wash bath, continuing its travel inside the transit ducts of rigid type 23' (or 24') and 23 (or 24). In this way, the fabric comes into contact with the edge of the lower port 22K' of the rotating transit duct 22' (or 25') and 22 (or 25) pushing the rotating part thereof 22F upward. This movement, as explained above, is detected by appropriate sensor means which send a signal to the motor M of the rotating drum 20' and 20 to reverse the movement thereof. At this point the fabric moves in the opposite direction and returns downward, i.e. into the wash water of the tank below.

[0090] Again simultaneously, new fabric enters the initial wash tank 11' of the first module 10' with speed V1<V2, and the same quantity of fabric exits from the final wash tank 12 of the second module 10 through the means for extracting 16; again simultaneously, the means for extracting 16' or for introducing 13, carry, with speed V1, the fabric from the second tank 12' of the first module 10' to the first tank 11 of the second module 10. In practice, the fabric as a whole passes through the machine with speed V1, while portions thereof are subjected to an alternate wash in the various tanks.

[0091] While the fabric moves inside the transit ducts 22, 23, 24, 25, 22', 23', 24', 25', it undergoes a further wash by means of water made to flow in these ducts. In particular, for each pair of transit ducts with outlets above a same tank, the water used for washing in the ducts is drawn from this tank below, sent by means of a pump 28, 28' and related pipes 30, 30'. In particular, the water that flows in the transit ducts always flows in the direction from a point of entry toward the discharge port (22K, 23K etc.) of the related transit duct. This means that alternately, the flow of water in the transit duct will flow once in the same direction as the direction of movement of the fabric and flow the next time in the opposite direction, giving rise, in this latter case to in a particularly effective washing action.

[0092] As already mentioned, the wash water of the tanks flows by gravity in succession from the final wash tank to the initial wash tank. The water that flows into the final wash tank (i.e. at the greatest height) is clean water, while the water that flows into the tanks below from this final tank becomes dirty due to the washes. In practice, the fabric is washed continuously with increasingly clean water as it advances through the machine.

[0093] Besides the machine, also the fact of washing the fabric in counter-current inside the transit ducts during the wash process is innovative. Therefore, the invention also relates to a method for continuous washing of fabric in rope form T which provides for:

• accumulating fabric in a first wash tank,
• moving in an alternate manner from the first wash tank to a second wash tank and vice versa with a movement speed,
• preferably simultaneously to the alternate movement, feeding fabric into the first tank and removing fabric from said second tank with a speed lower than the alternate movement speed, and,
• making the fabric pass through a flow of water with direction substantially opposite to the direction in which the fabric is moved.

[0094] As described, a step of a making the fabric pass through a flow of water with direction approximately opposite to the direction in which the fabric is moved occurs, for example, during the step of alternate movement of the fabric, i.e. when the fabric T exits from the first tank 11 of a base module to enter the second tank 12, or vice versa.

[0095] As described, another step of making the fabric pass through a flow of water with direction approximate opposite to the direction in which the fabric is moved occurs during exit of the fabric T from the base module, i.e. from the second tank 12 and also from the final wash tank of the machine.

[0096] Advantageously, in the preferred embodiment, the step of making the fabric pass through a flow of water with direction opposite occurs with the water flowing from the top downward and the fabric which is moved from the bottom upward, preferably according to a substantially vertical direction.

[0097] As already mentioned, the idea of the rotating transit duct to activate the means to reverse the direction of the fabric between two consecutive tanks, i.e. to indicate termination of the accumulation in a tank and control reversal of the direction of movement of the fabric, is synergically related to the concept of "back-washing", i.e. washing in the opposite direction to the water flowing inside transit ducts. At the same time however, this device (the rotating transit duct), can advantageously also be used in machines in which this innovative concept of "back-washing" is not applied, as it enables the reversal means to be activated in a rapid and safe manner and does not occupy much space.

[0098] The machine in the preferred embodiment can comprise several base modules 10 in series with one another, so that it is possible to obtain machines with 2, 4, 6, 8 tanks etc. (corresponding to 1, 2, 3, 4 modules etc.).

[0099] It is understood that the drawing only shows possible non-limiting embodiments of the invention, which can 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 provided purely to facilitate the reading thereof, in the light of the above description and accompanying drawings, and do not in any way limit the scope of protection.

Claims

1. Machine for continuous washing of fabric in rope form, which comprises two or more wash tanks (11, 12), including an initial wash tank (11) in which the fabric (T) is designed to enter at a first (V1) and a final wash tank (12) from which the fabric is designed to exit at the same said first speed (V1), fabric being accumulable in said wash tanks, said machine also comprising means for alternate movement (19) of the fabric between at least two consecutive wash tanks (11, 12) with a second movement speed (V2), greater with respect to said first speed (V1), in such a manner as to alternately accumulate fabric in said two consecutive wash tanks (11, 12), there being present at least one transit duct (22, 23, 24, 25) through which the fabric is designed to pass during passage inside the machine and along which the wash water is designed to flow; characterized in that it comprises hydraulic means flowing the wash water through at least one said transit duct (22, 23, 24, 25) in the opposite direction to the direction of movement of the fabric when it passes through the same duct; therefore a flow of water in the opposite direction to the advancing of the fabric in the same transit duct is obtained by means of said hydraulic means, causing an effective washing action.

2. A machine according to claim 1, comprising a transit duct (22, 24) for fabric entering a respective wash tank (11, 12) and/or a transit duct (23, 25) for fabric exiting from a respective wash tank (11. 12) wherein said transit duct for entering and/or exiting is provided with a discharge port (22K, 23K, 24K 25K) open onto a respective wash tank (11, 12) below; the wash water being made to flow toward this port.

3. A machine according to claim 1 or 2, wherein each wash tank (11, 12) is provided with a transit duct (22, 24) for entering fabric and a transit duct (23, 25) for fabric exiting, wherein the wash water flows toward said wash tank.

4. A machine according to one or more of the preceding claims, comprising a base module (10, 10') which comprises two wash tanks (11, 12), a first tank (11) in which fabric enters at said first speed (V1), a second tank (12) from which fabric exits at said first speed (V1) and between which there are provided said means for alternate movement (19) of the fabric between the two first and second tanks (11, 12) passing through respective transit ducts (22, 23, 24, 25).

5. A machine according to claim 4, comprising a single base module (10) formed by only two wash tanks (11, 12); the initial wash tank corresponding to the first tank of the aforesaid base module, and the final wash tank corresponding to the second wash tank of the base module.

6. A machine according to claim 4, comprising at least two base modules (10', 10) in series one after another, said means for alternate movement (19', 19) being arranged only between the wash tanks (11', 12', 11, 12) of respective base modules (10', 10), while between one base module (10') and the other (10) there are provided means (17') for extracting the fabric from a second tank (12') and means (13) for introducing the fabric into the subsequent first tank (11) of the following base module (10).

7. A machine according to one or more of the preceding claims, wherein each wash tank (11, 12) is provided with a transit duct (22, 24) for entering fabric and a transit duct (23, 25) for fabric exiting; through said fabric exiting/entering transit ducts the wash water flows toward said each wash tank.

8. A machine according to one or more of the claims 1 to 7, characterizing in that each wash tank (11, 12) is provided with a transit duct (22, 24) for entering fabric and a transit duct (23, 25) for fabric exiting; through said fabric exiting/entering transit ducts the wash water flows toward said each wash tank, and wherein said hydraulic means flowing the water through said two transit ducts (22, 23, 24, 25) act in a substantially simultaneous manner.

9. A machine according to one or more of the preceding claims, wherein the fabric passes through the transit duct (22) entering the first tank (11) always in the same direction as the flow of water flowing therethrough, while the fabric passes through the transit duct (25) exiting from the second tank (12) always in the opposite direction to the flow of water flowing through said duct (25).

10. A machine according to one or more of the preceding claims, wherein said means for alternate movement (19) of the fabric between the two wash tanks (11, 12) comprise a rotating driving member (20), preferably arranged above the outlets of the transit ducts (23, 24) of the fabric exiting and entering the two tanks (11, 12) in which the fabric is moved in alternate manner.

11. A machine according to one or more of the preceding claims, comprising a transit duct (22, 24) for fabric entering a respective wash tank (11, 12) and/or a transit duct (23, 25) for fabric exiting from a respective wash tank (11. 12) wherein said transit duct for entering and/or exiting is provided with a discharge port (22K, 23K, 24K 25K) open onto a respective wash tank (11, 12) below; the wash water being made to flow toward this port.

12. A method for continuous washing of fabric in rope form which provides for accumulating fabric (T) in a first wash tank (11), moving in an alternate manner from said first wash tank (11) to a second wash tank (12) and vice versa with a movement speed (V1) and, preferably simultaneously to the alternate movement (V1), feeding fabric (T) into said first tank (11) and removing fabric from said second tank (12) with a speed (V2) lower than the alternate movement speed (V1), characterized by making the fabric (T) pass through a flow of water with direction approximately opposite to the direction in which the fabric is moved.

Drawing