This invention relates to a machine for the discontinuous treatment of fabric ropes, of the type comprising the features described in the preamble to claim 1.

More particularly, the machine according to this invention is used during industrial processes relating to the production of fabrics and carries out various processing operations, such as dyeing, bleaching or washing.

For that purpose, the fabric is twisted over itself in such a way that it takes on the shape of a rope and is immersed in a treatment bath.

Prior art machines for this type of operation comprise a tank containing the treatment liquid bath and a plurality of motor-driven reels, each able to rotate about its own axis of rotation, on each of which a respective fabric rope to be treated rests, the fabric rope being closed in a loop and descending from the reel until it is in the bath and then rising from the bath on the opposite side of the reel. Each reel is contained in a respective box-shaped body positioned above the tank and is connected to the tank and supported by an away pipe for the fabric rope from the reel to the tank and a return pipe for the fabric from the tank to the reel. The fabric rope is circulated both by the rotation of the reel and because the fabric is struck by a jet of treatment liquid sprayed by suitable nozzles. Each of the nozzles is positioned in the away pipe and is connected to the tank. The treatment liquid to be sprayed is drawn from the bath and fed to the nozzles through a single recirculation duct which, at an upper portion of the tank, is divided into as many branches as there are ropes to be treated. In particular, the single duct of prior art machines enters a horizontal pipe extending along the tank alongside containers housing the reels. Extending from each opposite end of the horizontal pipe there is a duct with a smaller cross- section which leads to a respective nozzle located in a respective end container. Extending from separate points of an intermediate portion of the horizontal pipe there are as many ducts with a smaller cross-section, each connected to a respective nozzle located on the intermediate containers. In the lower part of the tank, partly or completely immersed in the bath, there is a perforated basket able to move relative to the tank in a direction which is transversal to the direction of feed of the fabric. The movement of the end of the fabric conveyor duct, in combination with fabric feed, allows the fabric to be zigzagged on the bottom of the basket in a regular fashion. The fabric rope which is closed in a loop is made to rotate inside the machine for the time necessary for treatment optimisation.

Such a machine is illustrated, for example, in public document EP 1 884 583 Bl.

The quantity of treatment liquid used must be such that it fills, to the correct level, the tank and the machine circuits (including the above-mentioned recirculation duct). The moving liquid contained in the circuits is in fact not useful for the purposes of the process and represents between approximately 25% and approximately 40% of the total quantity. Moreover, the structure of the horizontal pipe which acts as a manifold for the ducts which lead to the nozzles is such that it generates unevenness in the flow rate and pressure of the liquid sprayed on the various fabrics .

The Applicant saw the need to contain the quantity of treatment . liquid used in each cycle, consequently reducing the treatment costs and having less environmental impact, whilst maintaining and/or increasing the effectiveness of the treatment on the fabrics .

In this context, the technical purpose which forms the basis of this invention is to propose a machine for the discontinuous treatment of fabric ropes which allows a reduction in the quantity of treatment liquid moving in the circuits.

This invention also has for an aim to propose a machine for the discontinuous treatment of fabric ropes which allows the properties of the jets of treatment liquid emitted by the nozzles to be made more uniform.

The technical purpose specified and the aims indicated are substantially achieved by a machine for the discontinuous treatment of fabric ropes in which the branch ducts leading to the nozzles located close to the various reels extend in radial directions from a shared manifold .

More specifically, this invention relates to a machine for the discontinuous treatment of fabric ropes, comprising :

a main tank delimiting an inner volume for the containment of a treatment liquid bath; a plurality of motor-driven reels positioned at an upper portion of the tank and each designed to support and guide a respective fabric rope along a closed treatment path in the main tank;

at least one spraying nozzle located close to each of the motor-driven reels and facing towards the respective fabric rope for dispensing against the fabric rope a pressurised jet of the treatment liquid;

a recirculation duct whose first end is connected to a lower portion of the tank and whose second end is in fluid communication with the nozzles;

a pump operating on the recirculation duct;

a manifold connected to the second end of the recirculation duct and extending away from the second end along a main axis; a plurality of branch tubes extending from the manifold and connected to the nozzles ;

characterised in that the branch tubes come out of the manifold spoke-style from positions which are located substantially at the same height along the main axis of the manifold.

That solution allows a reduction in the quantity of bath circulating in the machine ducts, that is to say, it allows a reduction in the quantity of bath which is not useful for the purposes of the process. The new system achieves a reduction in the quantity of bath circulating, compared with prior art machines, equal to approximately 10% of the free bath (that not retained in the fabric) and a percentage equal to approximately 20 - 30% of the quantity of bath circulating in the machine pipes. In a machine containing approximately 2700 litres of free bath and a total of approximately 5800 litres of treatment liquid, the reduction is no less than 270 litres for each treatment cycle.

Moreover, this solution allows an improvement in the system for distribution of the treatment liquid to the nozzles designed to move the fabric. Compared with prior art manifolds, this solution guarantees greater uniformity of flow rates and feed pressures between the various branch tubes.

The branch tubes which feed the nozzles are connected to the manifold in a region of the manifold in which the pressure is constant.

In other words, all of the branch tubes are fed with the treatment liquid at the same pressure.

The manifold preferably has the shape of a cylinder and the branch tubes come out of a lateral wall of the cylindrical manifold.

The main axis of the cylindrical manifold is preferably vertical .

The branch tubes are preferably positioned in a horizontal plane.

Each of the branch tubes preferably has a cross-section area which is constant from the manifold to the at least one respective nozzle.

The branch tubes preferably have identical cross-section areas.

Each of the preferred features listed above helps to improve the uniformity of the flow rates and feed pressures between the various branch tubes.

In a preferred embodiment, the machine also comprises a heat exchanger inserted in a cylindrical body positioned along the recirculation duct and the manifold is positioned above and supported by the cylindrical body and preferably integrated in the cylindrical body.

That preferred embodiment allows a component which is already present (the heat exchanger) to be used to support the manifold, without having to provide additional supporting frames which would increase machine dimensions and cost.

Further features and advantages of this invention are more apparent in the detailed description below, with reference to a preferred, non-limiting, embodiment of a machine for the discontinuous treatment of fabric ropes, illustrated in the accompanying drawings, in which:

- Figure 1 is a schematic side view, partly in cross- section, of a machine for the discontinuous treatment of fabric ropes in accordance with this invention;

- Figure 2 is a top view of the machine of Figure 1. In the accompanying drawings, the numeral 1 denotes in its entirety a machine for the discontinuous treatment of fabric ropes in accordance with this invention.

The machine 1 comprises a main tank 2 designed to receive, in its internally delimited volume, a treatment liquid, which may for example, be a dye for dyeing the fabric rope "T", or a detergent for subjecting the fabric "T" to a washing cycle. The tank 2 illustrated is a cylinder with a horizontal main axis "Y - Y" . The liquid forms a bath 3 which occupies the lower part of the main tank 2 (visible in Figure 1) .

In the upper part of the machine 1, above the tank 2, there is a plurality of reels 4 (six are shown in the example illustrated) , each being motor-driven and able to rotate about its own horizontal axis of rotation. Each reel 4 supports and guides a respective rope formed by a fabric "T" along a closed treatment path in the main tank 2 (Figure 1) . Each reel 4 is positioned inside a box-shaped container 5 mounted above the tank 2 by means of a first tubular body 6 and a second tubular body 7. The box-shaped containers 5 are aligned with each other and positioned along an axis parallel with the main axis "Y - Y" of the main body 2 (Figure 2) . The tubular bodies 6, 7, as well as supporting the box- shaped container 5, put the reel 4 in communication with the inside of the main tank 2. The fabric rope "T" descends from the reel 4 into the tank 2 through the first tubular body 6 and ascends again from the tank 2 to the reel 4 through the second tubular body 7 (Figure 1) .

Inserted in the first tubular body 6 there is at least one movement nozzle (not illustrated) angled at an acute angle to the direction of feed of the rope "T", for dispensing against the fabric rope "T" a pressurised jet of the treatment liquid drawn from the bottom of the main tank 2 through a recirculation duct 8 equipped with a pump "P" (Figure 1) . Said nozzle performs the dual function of wetting the fabric "T", before immersion, and providing the thrust to make it advance towards the bath 3.

The recirculation duct 8 has a first end 9 connected to the bottom of the tank 2 and a second end 10 connected to the bottom of a cylindrical body 11 with a vertical axis which, in the known way, contains a heat exchanger. The pump ^¾ P" is positioned on the duct 8 between the tank 2 and the cylindrical body 11 (Figure 1) .

At an upper end of the cylindrical body 11 there is a manifold 12 integrated in the cylindrical body 11 and therefore comprising a cylindrical lateral wall 13 shared with the cylindrical body 11 and an upper wall 14 which closes the top of the cylindrical body 11. The manifold 12 internally delimits a cylindrical volume separated from the heat exchanger by a partition 15 comprising at least one passage for the treatment liquid.

The manifold 12 has a main axis "X - X".

In particular, as shown in Figure 1, the main axis "X - X" is vertical and the manifold 12 is positioned substantially at the same height as the first tubular bodies 6.

Extending from the lateral wall 13 there are as many branch tubes 16 as there are reels 5. Each branch tube 16 connects the manifold 12 to the one or more movement nozzles located in a single first tubular body 6.

Each branch tube 16 comprises at least a first stretch 16a, close to the manifold 12, extending in a radial direction relative to the vertical main axis ^, X - X" -of the manifold 12.

The branch tubes 16 extend from positions which are substantially located at the same height along the main axis "X - X" of the manifold 12.

In other words, the branch tubes 16 extend radially around the same annular portion of the manifold 12, in such a way that all of the tubes are fed with treatment liquid at the same pressure. In particular, the branch tubes 16 extend in the same horizontal plane substantially as far as the first tubular bodies 6. Figure 1 shows one of the branch tubes 16 which remains in the above-mentioned horizontal plane from the manifold 12 until it is close to the first tubular body 6, where there is a slight bend so as to make the branch tube 16 go into the first tubular body 6 in a direction perpendicular to the first tubular body 6.

Figure 2 shows how each of the branch tubes 16, which extend radially from the manifold 12, comprises a curve close to the respective first tubular body 6 in such a way that the tube is positioned perpendicular to the axis "Y - Y" of the tank 2.

The cross-section area of each branch tube 16 is constant along the longitudinal extension of the tube 16 (from the manifold 12 to the first tubular body 6) . The branch tubes 16 also have identical cross-sections.

As shown in Figure 2, in the example embodiment illustrated, the manifold 12 and the branch tubes 16 are symmetrical relative to a plane of symmetry "S" of the tank 2. Said plane "S" cuts the tank 2 in half and is perpendicular to the main axis "Y - Y" of the tank 2.