GB2364329A

GB2364329A - Jet dyeing machine for and method of dyeing a fabric rope

Info

Publication number: GB2364329A
Application number: GB0016345A
Authority: GB
Inventors: Tak Ming William Tsui; Sou Lam Fong
Original assignee: Falmer Investments Ltd
Current assignee: Falmer Investments Ltd
Priority date: 2000-07-03
Filing date: 2000-07-03
Publication date: 2002-01-23
Anticipated expiration: 2020-07-03
Also published as: GB0016345D0; TW541381B; CN1332286A; CN100393932C; GB2364329B; HK1042531A1

Abstract

The present invention relates to a jet dyeing machine for and a method of dyeing a fabric rope. The jet dyeing machine includes a counter flow fluid nozzle assembly (16) for applying dye liquor to a fabric rope (14) drawn in use therethrough, the nozzle assembly (16) being configured to provide a flow of dye liquor counter to the direction of travel of the fabric rope (14).

Description

2364329 JET DYEING MACHINE FOR AND METHOD OF DYEING A FABRIC ROPE The

present invention relates generally to a jet dyeing machine for and a method of dyeing a fabric rope, and particularly to a component thereof that forms part of a 5 nozzle assembly for injecting dye liquor onto and into a fabric rope.

Fabric rope is a width of fabric that is compressed and twisted into a rope-like section. Dye liquor or dye stuff is a mixture of water and dye chemicals which together form a water-based solution.

A jet dyeing machine is used for dyeing batches of fabric rope. The term jet refers to the device that provides some of the motive force for propelling a fabric rope. The same jet may also be used to inject dye liquor onto and into a fabric rope. The term dyeing refers to the process by which dye is introduced onto and into the fibres of a fabric rope. A fluid nozzle is a device that in ects fluid, particularly dye liquor, at a j high velocity uniformly around the circumference and into the body of a moving fabric rope. A driving reel is a rotating cylindrical open cage with an outside contacting surface composed of evenly spaced rectangular sections disposed around the perimeter thereof. A fabric rope is wrapped around this reel while an external device provides 20 continuous rotation. A non-driven reel, or free roller, is a component where rotation is provided by the friction of a fabric rope on passing thereover. An air jet is a nozzle where air is injected at a high velocity uniformly around the circumference and into the body of a moving fabric rope. A disengaging device is a device that promotes the removal of excess dye liquor from a fabric rope before reaching a driving reel and 25 entering an air jet. A collector is a device and/or assembly that collects unused dye liquor after being sprayed onto a moving fabric rope. The collector also channels dye liquor from a disengaging device and directs this dye liquor to a central channel. The collected dye liquor is directed to a pump and recycled. A fabric chamber is a metal container with perforated holes that contains plaited fabric rope, often submerged in 30 dye liquor. The fabric chamber is a separate container that is supported off the bottom of a main pressure vessel body.

A conventional jet dyeing machine, as illustrated in Figures 3 and 4, includes a main, driving reel 1, a nozzle 2 and a fabric chamber 3, over or through which a fabric rope 4 is directed. One drawback of this conventional design is that the fabric rope 4 is tensioned on being lifted abruptly from the fabric chamber 3 by the driving reel 1. If 5 the plaiting or packing of the fabric rope 4 is not uniform, an even higher tension is required to pull the fabric rope 4 free from the mass of fabric in the fabric chamber 3, often causing slippage on the driving reel 1. As slippage tends to occur at higher speeds, there can be a speed limitation for some fabrics. In this conventional dyeing machine the nozzle 2 serves two purposes, firstly to provide a motive or driving force 10 and secondly to introduce fresh dye liquor onto and into the fabric rope 4. There are, however, circumstances when these requirements conflict with each other. For example, a high fluid velocity in the nozzle 2 may be detrimental when treating gentle or delicate fabrics, but at the same time a high fluid velocity is required to achieve a high throughput.

Accordingly, the present invention provides a dyeing machine for dyeing a fabric rope, including a counter flow fluid nozzle assembly for applying dye liquor to a fabric rope drawn in use therethrough, the nozzle assembly being configured to provide a flow of dye liquor counter to the direction of travel of the fabric rope.

Preferably, the flow of dye liquor is uniform about the periphery of the fabric rope.

Preferably, the nozzle assembly includes a flooded section in which a volume of dye liquor is in use maintained.

Preferably, the dyeing machine further includes a driving reel downstream of the nozzle assembly for at least in part drawing the fabric rope through the nozzle assembly.

3 30 Preferably, the dyeing machine further includes a gas jet downstream of the nozzle assembly for at least in part drawing the fabric rope through the nozzle assembly.

Preferably, the nozzle assembly is configured such that the flow of dye liquor and the path of the fabric rope therethrough are inclined to the horizontal.

Preferably, the dyeing machine further includes a disengaging section downstream of 5 the nozzle assembly in which excess dye liquor can separate from the fabric rope.

Preferably, the dyeing machine further includes means for collecting and recycling the dye liquor from the nozzle assembly.

10 The present invention also provides a method of dyeing a fabric rope, comprising the steps of drawing a fabric rope through a nozzle assembly, and providing a flow of dye liquor in the nozzle assembly counter to the direction of travel of the fabric rope so as to apply dye liquor to the fabric rope.

15 Preferably, the flow of dye liquor is uniform about the periphery of the fabric rope.

Preferably, the method further comprises the step of maintaining a volume of dye liquor in the nozzle assembly through which the fabric rope is drawn.

20 Preferably, the fabric rope is at least in part drawn by a driving reel downstream of the nozzle assembly.

Preferably, the fabric rope is at least in part drawn by a gas jet downstream of the nozzle assembly.

Preferably, the flow of dye liquor and the path of the fabric rope are inclined to the horizontal.

Preferably, the method farther comprises the step of separating excess dye liquor from 30 the fabric rope exiting the nozzle assembly.

Preferably, the method further comprises the steps of collecting and recycling the dye liquor from the nozzle assembly.

In a preferred embodiment the dye liquor is sprayed onto the fabric rope at the upper 5 end of the nozzle assembly and flows downward while the fabric rope is propelled upwards by the combined action of the driving reel and the motive force of the gas jet. Excess dye liquor separates from the fabric rope before reaching the driving reel, and the bulk of the unused dye liquor is drained, collected and recycled from lower sections of the nozzle assembly.

The dyeing machine of the present invention provides improved dyeing uniformity, reduces friction and tension effects on the fabric rope and provides an increased quantity of cleaner dye liquor for recycling.

15 In the present invention the fabric rope is only under any real tension between the nozzle assembly and the driving reel, with the flooded nozzle assembly being designed solely to apply fresh dye liquor to the fabric rope, the gas jet being dedicated to provide a motive force, and the inclined section of the nozzle assembly from the top of the fabric chamber eliminating the abrupt lift of the conventional design.

In such a jet dyeing machine, the process of dyeing is facilitated by the transfer of dye liquor to the interior of the fabric rope. Some important considerations are: i) to maximise the speed of the fabric rope which translates to increased capacity; ii) the ability to handle a wide range of fabrics without causing adverse friction or tension 25 effects which may effect the fabric finish and appearance; and iii) to reduce the working volume of the dye liquor. As chemicals must be added to the dye liquor and the dye liquor has to be heated and cooled during the dyeing process, the less dye liquor employed, the less chemicals are required and the less heat that has to be introduced.

Capacity can be increased by increasing the linear speed of the fabric rope. This is possible because of the combined effect of the gas jet and the counter flow fluid nozzle assembly. The gas jet is able to drive the fabric rope at a much higher velocity than a conventional liquid jet.

It is also possible to reduce the tension and other surface effects on the fabric rope.

5 The fabric rope is gently pulled up a slope to the fluid nozzle, from which there is a very short distance to the driving reel. In conventional jet dyeing machines there is a large distance between the driving reel and the main body of liquor.

The use of a flooded section provides a region where dye liquor can be introduced into 10 the fabric rope. By providing a flooded section, the volume of dye liquor required in the main vessel of the dyeing machine is reduced and the unused clean dye liquor from the nozzle assembly can be recycled. In conventional jet dyeing machines, the liquor is injected over a short range, where the flooded zone is turbulent and relatively short.

15 By virtue of the present invention it is possible to provide a broader range of operating conditions to suit a wider range of different fabrics and minimise the dye unevenness between regions where the dye first "strikes" and the last regions to be dyed.

The jet -dyeing machine of the present invention has two particularly advantageous 20 features, namely a continuously moving fabric rope and a continuously circulating dye liquor.

In use, the jet dyeing machine is first loaded with many hundreds of metres of fabric rope, The two ends of the rope section are joined together to form an endless rope 25 which is continuously circulated inside the machine. The fabric rope is pulled from the fabric chamber, around a free roller, directed up and through the counter flow fluid nozzle assembly, around the driving reel, down through the gas jet, and finally plaited into the fabric chamber filled with dye liquor. The plaited fabric in the fabric chamber is moved slowly from the front to the rear of the machine where once again it is pulled 30 up and into the counter flow fluid nozzle assembly. The jet dyeing machine is also equipped with a circulation pump and a heat exchanger. Dye liquor from the collector and the main vessel is circulated by the pump through the heat exchanger and up to the counter flow fluid nozzle assembly.

If the fabric rope were to contact the dye liquor only once while in the fabric chamber, 5 then the dyeing would be more uneven and much slower. Fibres on the external surface of the fabric rope that are contacted first are exposed to the most concentrated dye liquor. If the dye liquor is permitted to strike the outside of the fabric rope only, it may take a long time for the concentration level to equilibrate in the mass of the fibres. This equilibration will eventually be achieved by a process referred to as migration, 10 whereby dye in the more concentrated regions tends to transfer back into the dye liquor as the concentration of the dye liquor decreases, and thus be transferred to the fibres which have absorbed lower amounts of dye.

Temperature is a driving force by which many dye stuffs are absorbed into fibre 15 molecules. Raising the temperature, while accelerating the dyeing process, may also increase initial unevenness, which will increase the amount of migration needed to bring the fibres back to a level basis. The time required for migration is many times greater than the time required for a mere application phase, and it is clearly advantageous to take steps to reduce the need for migration by providing conditions to 20 encourage the dye liquor to strike as evenly as possible.

In this regard, the arrangement and placement of the counter fluid flow nozzle is as important as the design of the counter flow fluid nozzle assembly.

25 A preferred embodiment of the present invention will now be described hereiribelow by way of example only with reference to the accompanying drawings, in which:

Figure I illustrates a jet dyeing machine including a counter flow fluid nozzle assembly in accordance with a preferred embodiment of the present invention; Figure 2 illustrates a more detailed view of the counter flow fluid nozzle assembly of the jet dyeing machine of Figure 1; and Figures 3 and 4 illustrate views of conventional jet dyeing machines.

The jet dyeing machine includes a dyeing vessel 8, providing a reservoir in the bottom 5 9 of which dye liquor 10 collects, a fabric chamber 13, located above the bottom 9 of the dyeing vessel 8, through which a plaited fabric rope 14 is guided, and a free roller 15, located at a rear section of the machine just above the fabric chamber 13, over which the fabric rope 14 is drawn.

10 The jet dyeing machine further includes a counter flow fluid nozzle assembly 16 through which the fabric rope 14 is directed. The counter flow fluid nozzle assembly 16 includes a lower drainage section 17 inclined to the horizontal and extending to the free roller 15, and a main collection channel 18 located below the free roller 15.

15 The counter flow fluid nozzle assembly 16 further includes a fluid nozzle 19 for applying dye liquor to the fabric rope 14. The fluid nozzle 19 includes an inlet 20 though which dye liquor is introduced and a flooded section 21 containing a volume of dye liquor through which the fabric rope 14 is drawn. The flooded section 21 provides uniform, laminar flow around the fabric rope 14 which is non-turbulent and free of 20 bubbles. In use, the fabric rope 14 travels up, suspended and on top of, the open collection channel 18, but does not touch any surfaces, in this embodiment metal surfaces, until reaching the fluid nozzle 19, with the flow of dye liquor being directed counter to, that is against, the direction of travel of the fabric rope 14.

25 The counter flow fluid nozzle assembly 16 further includes a disengaging section 22 where the excess dye liquor separates from the fabric rope 14. It is important that not too much dye liquor is carried over by the fabric rope 14.

The jet dyeing machine further includes a main, driving reel 23 which in part draws 3 30 the fabric rope 14 up through the counter flow fluid nozzle assembly 16, an air jet nozzle 24 located downstream of the driving reel 23 for propelling the fabric rope 14, and a plaiter 25 located downstream of the air jet nozzle 24. The fabric rope 14 is plaited by the plaiter 25 and fed into the front end of the fabric chamber 13. The fabric chamber 13 holds a majority of the fabric load, and acts as a buffer, through which the fabric rope 14 is slowly transported to the rear of the machine, until drawn again through the counter flow fluid nozzle assembly 16.

Compared to the conventional dyeing machine of Figures 3 and 4, in particular the path of the fabric rope 14 on being drawn up through the counter flow fluid nozzle assembly 16, over the driving reel 23 and through the plaiter 25, it will be seen that in the present invention the direction of travel of the fabric rope 14 is in the opposite 10 direction, the counter flow fluid nozzle assembly 16 is upstream of the driving reel 23, and an air jet nozzle 24 is provided downstream of the driving reel 23.

Finally, it will be understood that the present invention has been described in its preferred embodiment and can be modified in many different ways without departing 15 from the scope of the invention as defined by the appended claims.

9

Claims

1. A jet dyeing machine for dyeing a fabric rope, including a counter flow fluid nozzle assembly for applying dye liquor to a fabric rope drawn in use 5 therethrough, the nozzle assembly being configured to provide a flow of dye liquor counter to the direction of travel of the fabric rope.

2. The dyeing machine of claim 1, wherein the flow of dye liquor is uniform about the periphery of the fabric rope.

3. The dyeing machine of claim I or 2, wherein the nozzle assembly includes a flooded section in which a volume of dye liquor is in use maintained.

4. The dyeing machine of any of claims 1 to 3, further including a driving reel 15 downstream of the nozzle assembly for at least in part drawing the fabric rope through the nozzle assembly.

5. The dyeing machine of any of claims I to 4, further including a gas jet downstream of the nozzle assembly for at least in part drawing the fabric rope 20 through the nozzle assembly.

6. The dyeing machine of any of claims I to 5, wherein the nozzle assembly is configured such that the flow of dye liquor and the path of the fabric rope therethrough are inclined to the horizontal.

7. The dyeing machine of any of claims 1 to 6, further including a disengaging section downstream of the nozzle assembly in which excess dye liquor can separate form the fabric rope.

8. The dyeing machine of any of claims I to 7, further including means for collecting and recycling the dye liquor from the nozzle assembly.

9. A method of dyeing a fabric rope, comprising the steps of drawing a fabric rope through a nozzle assembly, and providing a flow of dye liquor in the nozzle assembly counter to the direction of travel of the fabric rope so as to apply dye liquor to the fabric rope.

10. The method of claim 9, wherein the flow of dye liquor is uniform about the periphery of the fabric rope.

10 11. The method of claim 9 or 10, further comprising the step of maintaining a volume of dye liquor in the nozzle assembly through which the fabric rope is drawn.

12. The method of any of claims 9 to 11, wherein the fabric rope is drawn at least in 15 part by a driving reel downstream of the nozzle assembly.

I I The method of any of claims 9 to 12, wherein the fabric rope is drawn at least in part by a gas jet downstream of the nozzle assembly.

20 14. The method of any of claims 9 to 13, wherein the flow of dye liquor and the path of the fabric rope therethrough are inclined to the horizontal.

15. The method of any of claims 9 to 14, further comprising the step of separating excess dye liquor from the fabric rope exiting the nozzle assembly.

16. The method of any of claims 9 to 15, further comprising the steps of collecting and recycling the dye liquor from the nozzle assembly.

17. A jet dyeing machine for dyeing a fabric rope substantially as hereinbefore 30 described and illustrated with reference to Figures I and 2 of the accompanying drawings.

18. A method of dyeing a fabric rope substantially as hereinbefore described and illustrated with reference to Figures I and 2 of the accompanying drawings.