GB2060849A

GB2060849A - A machine for and method of producing treating or finishing a fabric

Info

Publication number: GB2060849A
Application number: GB8031018A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1979-10-06
Filing date: 1980-09-25
Publication date: 1981-05-07
Also published as: GB2060849B

Abstract

A machine for and method of producing, treating or finishing a fabric. The machine comprises four heated rollers 1, 2, 4, 5 and two untreated rollers 3 and 6. The rollers are placed adjacent each other to define nips therebetween. Guide rollers 7 to 12 define two endless paths with the treatment rollers around which paths two PTFE coated endless belts 13 and 14 run. These paths have a common section running through the nips of the treatment rollers. Fabric fed through the common section is held between the belts in a controlled manner whilst being successively heated and cooled.

Description

SPECIFICATION A machine for and method of producing treating or finishing a fabric The present invention relates to a machine for producing, treating or finishing fabrics in the piece.

At the present time, in a textile finishing process, it is usualiy necessary as the final step, or one of the final steps, to dry the fabric. This is generally done by feeding the fabric progressively through a drying oven.

Extreme care must be taken in handling the fabric at this time since any distortion produced in the fabric may be permanently set into the fabric by the drying process. For example, if the fabric is subjected to undue stress in the lengthwise direction of the fabric this resuits in necking which in turn results in a reduction of the width of the fabric. To prevent, or at least reduce the risk of, this happening the material is held on both longitudinal edges at relatively closely spaced points as it passes through the oven. Such a machine, which is called a stenter, is complicated and expensive.

In other processes such as the coating of fabrics, for example, with a gellable or curable synthetic plastics material, it is also necessary to pass the material through a drying gelling or curing oven. Here the fabric to be coated is, in one method, passed under a bath of the coating material and a precisely settable gap between a knife and a roller supporting the coated material controls the thickness of the coating. Thereafter the material is passed through the oven to gell or cure the coating material. In such a machine there are also difficulties in supporting the fabric without distortion in its passage through the oven.

Although the fabric can be coated on both sides the additional weight thus placed on the fabric may result in an unacceptable sagging of the material in the oven bringing the material close to or actually in contact with the oven with possibly disastrous consequences.

These problems can to some extent be offset by reducing the unsupported travel of the coated material through the oven, but this also reduces the heat which can be imparted to the material and may result in additional passes through the machine being required with consequent increase in process times and expense. These problems may also be offset by employing archback flotation ovens, but such machines are complicated and expensive to produce and operate.

According to one aspect of the present invention, there is provided a fabric production treatment, or finishing machine comprising a plurality of guides disposed to provide two endless paths each having a common section passing over a heatable curved treatment surface, two endless belts disposed for movement around respective endless paths, and means for feeding in a fabric to be treated on the treatment surface so that the fabric is received between the belts during its passage over the surface, the arrangement being such that fabric can be successively heated and cooled whilst sandwiched between the belts.

A preferred embodiment of the invention may include any one or more of the following advantageous features:- (a) The curved treatment surface is constituted by the surface of a heatable treatment roller.

(b) An unheated treatment roller is disposed downstream of the heatable roller of (a) and lying on the common section.

(c) The heatable treatment roller of (a) and the unheated treatment roller of (b) are arranged relative to one another to define a nip therebetween lying on the common section.

(d) Two heatable treatment rollers are disposed adjacent one another to define a nip lying on the common section.

(e) An unheated treatment roller lies downstream of the heatable rollers of (d) on the common section.

(f) There are three pairs of treatment rollers.

(g) Two of the three pairs of treatment rollers of (f) are heatable.

(h) The or each heatable curved treatment surface is oil or steam heated.

(i) The or each heatable curved treatment surface is electrically heated.

(j) The means for feeding in a fabric comprises a take-off roller.

(k) The endless belts are coated with a low friction material.

(I) The belts have a woven glass fibre base with a silicon rubber coating.

(m) The belts have a woven glass fibre base with polytetrafluoroethylene coating.

(n) Apparatus is provided for coating the fabric before gentry into the treatment rollers.

(o) A reel-up roller is provided to receive the fabric after leaving the common section.

(p) One or the treatment roller is directly driven and any other treatment rollers are directly driven from that directly driven treatment roller.

(q) The reel-up roller of (o) is directly driven or indirectly driven from the driven treatment roller of (p).

(r) One or both of the belts may be in the form of a lattice.

(s) Where there are two rollers defining a nip, the nip is fixed and has a dimension less than the sum of the thicknesses of the two endless belts and the fabric passing therethrough in operation of the machine.

(t) Where there are two rollers defining a nip one of the rollers defining the nip is fixed and the other is movable and can be pressured to squeese the belts and fabric passing therethrough during operation of the machine.

(u) Where there are two rollers defining a nip, the nip is nominally fixed but one of the rollers defining the nip is movable so that it can adjust to varying thicknesses of belt and fabric passing therethrough during operation of the machine.

(v) The belts are tensioned to squeeze the fabric during operation of the machine.

(w) Those parts of the machine supporting the endless belts are cantilevered to facilitate removal and replacement of the belts.

According to another aspect of the present invention, there is provided a method of producing, treating or finishing a fabric including the steps of sandwiching a fabric between two belts of material, passing the sandwich so formed over a heated curved treatment surface so as to heat it, cooling the sandwich to cool the fabric, and then removing the fabric from between the two belts.

The invention also comprises a fabric produced, treated or finished on the above defined machine or by the above defined method.

In order that the invention may be more clearly understood, one embodiment thereof will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a diagrammatic side elevational view of a fabric coating machine, and Figure 2 shows a side elevational view of a fabric treatment machine.

Referring to Fig. 1, the machine comprises six treatment rollers 1 to 6 arranged in two rows with the rollers of one row adjacent but staggered relative to the rollers in the other row, such that a total of five nips are formed therebetween. Six guide rollers 7 to 1 2 are disposed around the array of treatment rollers.

A first, upper, endless belt 1 3 is guided by the guide rollers 7, 8 and 9 and runs through the five nips formed by the treatment rollers 1 to 6. A second, lower, endless belt 14 is guided by the guide rollers 9, 1 O, 11 and 12 and also runs through the five nips formed by the treatment rollers 1 to 6. Both endless belts 1 3 and 14 comprise a woven glass fibre base coated with polytetrafluoroethylene (PTFE) or other similar low friction material.

An alternative belt, for example, comprises a woven glass fibre base coated with silicone rubber. The type of belt chosen is chosen in dependence upon the fabric being produced, treated or finished and upon the nature of the process itself. Bn some processes, for example, it has been found advantageous to employ silicone rubber coated glass fibre woven belts where the coating is very thin on one side, but approximately 15 X 10-3 inches thick on the other side. Again, if desired, the sur face of the belt could be dimpled or otherwise specially formed.

There are two further rollers, respectively referenced 15 and 16. Roller 15 is a lead in roller from which the fabric 1 7 to be treated is supplied and roller 1 6 is a reel-up roller on which the treated fabric is taken up. The guide rollers 7 and 1 2 are disposed in relation to the first roller 1 of the treatment roller array, such that the belts 1 3 and 14 form an acute "V" shape and the lead in roller 1 5 is disposed in relation to the rollers 1, 7 and 1 2 such that the fabric 1 7 to be treated enters the array equidistantly spaced from the belts 13 and 14.

A double sided coating apparatus 1 8 is disposed for coating the fabric leaving the roller 1 5. The coating material may, for example, be polyvinyl chloride (P.V.C.).

Four (referenced 1, 2, 4 and 5) of the six treatment rollers are heated and the remaining two 3 and 6 are cold. The heated rollers are preferably electrically heated, but steam or other means may be used as desired. When steam or other heating medium is used rotatable joints are required for conducting steam from outside the treatment rollers 1, 2, 4 and 5 to the interior of the rollers. For example, the heating medium could be electrically heated oil. The rollers are preferably of stainless steel but may be made of any other suitable material. The rollers 1 to 6 are drivably connected together and one treatment roller is itself directly driven, this drive being transmitted to the other rollers by the drive connection.The five nips between the treatment rollers 1 to 6 are precisely adjusted usually to a dimension less than the thickness of the finished fabric to be treated and the two belts 13 and 14.

In operation of the machine, the fabric is drawn through the treatment rollers by the rotation of the treatment rollers themselves.

As it is drawn off the roller 1 5, the fabric 1 7 is coated by the apparatus 18, and as the coated fabric reaches the first treatment roller lit is clasped between the two PTFE belts 1 3 and 14. The belts 13 and 14 and fabric 17 move in synchronism through the treatment roller array and are heated as they do so thus promoting gelation of the coating. After gelation, the fabric is cooled by being passed, still between the belts 1 3 and 14, over the cold rollers 3 and 6. There will be a tendency for the cold rollers 3 and 6 to pick up heat from the fabric and in order to maintain the rollers at the required low temperature (i.e. un heated) cooling of these rollers may be necessary. At the guide roller 9 the belts 1 3 and 14 again follow their separate paths and the coated fabric passes to the reel-up roller 1 6.

This roller 1 6 may be driven independently or from a drive take-off from the treatment rol lers. Because of the nature of the belts 1 3 and 14 and the fact that the coating has been cooled there is no damaging adhesion between the belts and fabric at the roller 9 or between adjacent turns of the fabric on the roller 16.

Fig. 2 is a more detailed drawing of a modified version of the machine shown in Fig.

1. As compared with the machine of Fig. 1, the machine of Fig. 2 comprises only four treatment rollers 201, 202, 204 and 205 arranged in relation to one another to define three nips therebetween. Eight guide rollers 208 to 212 and 230 to 232 are disposed around the array of treatment rollers. A first, rollers 21 land 212. The rollers 230 and 231 are mounted in a bracket 243 which is itself mounted for pivotal movement about a pivot treatment rollers. A second, lower, endless belt 214 is guided by the guide rollers 209, 232, 210, 211 and 212 and also runs through the three nips. Bath endless belts 213, 214 are of similar construction and material to the belts 13 and 14 of the machine of Fig. 1. Rollers 204 and 205 can be adjusted by means of respective adjustment mechanisms 235 and 236 so that the dimensions of the nips can be adjusted.Guide rollers 208 and 232 are mounted on adjustment mechanisms 250 and 251 to permit adjustment of the rollers 208 and 232 to tension respective belts 213 and 214.

A lead in roller 215 is provided on a support 237 from which the fabric 217 to be treated is supplied and a reel-up roller 216 is provided on a support 238 on which the treated fabric is taken up. The supports 237 and 238 are themselves connected to a main support 239 to which the main frame of the machine 240 is also connected. The support for the various rollers is cantilevered to facilitate removal and replacement of the endless belts 213 and 214.

A belt sensing unit 241 is associated with the guide rollers 230 and 231 and a belt sensing unit 242 is associated with the guide rollers 211 and 212.The rollers 230 and 231 are mounted in a bracket 243 which is itself mounted for pivotal movement about a pivot 244. The rollers 230 and 231, bracket 243 and belt sensing unit 241 together form a tracking assembly for the belt 213. Guide rollers 211 and 212 are mounted in a bracket 245 which is itself mounted for pivotal movement about a pivot 246. These rollers 211 and 212 and bracket 245 form together with the sensing unit 242 a belt tracking assembly for the belt 214. The sensing units 241 and 242 may be optical (for example comprising a photoelectric cell) or mechanical (for example working on an air jet).The tracking assem blies serve to keep the belts 213 3 and 214 in position by continuously sensing and correcting any tendency of the belts to stray from their desired paths.

Treatment rollers 201, 202 and 204 are heated and roller 205 is unheated. The treatment rollers are substantially of the same construction and material as those of the machine of Figure 1. In particular the heated rollers may be electrically steam or oil heated.

The treatment rollers are auso driven in the same way as those o. the machine of Fig. 1.

The machine is operated in the same manner as the machine of Fig. 1, the fabric being produced, treated or finished being successively heated and cooled and, although a coating head has not been described, one could clearly be added if desired.

The above described machines and method may be employed for the gelation of PVC plies where the lead in is almost ideal or for general PVC gelation use. One or both sides can be gelled in one pass and heavier coated fabric weights can be accommodated than hitherto.

Energy saving as compared to conventional processes could be 40/50% of the cost of the machine may well only be one half of that of a conventional drying oven. Less space (up to 75%) is also required for the machine.

The method and machines described may also be used for fabric to fabric larnination with adhesive, with the energy, cost and space having mentioned above. They may also be used for heat Setti.rg i fabrics such as nylon and polyester. or heat seting of natural fabrics, resin curing arrier drying in conven tional finishing, or simpl-vR to dry a fabric.

When simple drying is the objet. one or both of the belts may be in the form of a lattice.

With the above described method and ma- chine, the fabric being treated is positively held whilst bering heated and cooled. iarking off faults associated with drawing of the fabric from a hot drum whilst itself is still hot can therefore be avoided.

It will be appreciated shaW the above embod- iment has been described by way of e;:ample only and that many variations are possible without departing from she scope of the invention claimed. For example, in any use of the described machine of Fig. 1 not involving fabric coaling, the coating apparatus 1 8 would clearly not be necessary and could be dispensed with. Where fabrics are to be coated with a solvent or aqueous coating, the upper endless belt 1 3 of the machine of Fig.

1 preferably follows the alternative path shown in the drawing by a dashed line. For this purpose, the guide roller 7 would be replaced by a differently disposed guide roller 30. Again. instead cf having coating apparatus 18. coating apparatus 40 could be provided for coating the upper surface of the bottom belt as shown in dashed outline in the drawing.

Although the nips be wean the rollers of the two described machines are adjustable, once adjusted. they are fixed at a gap dimension slightly less than the thickness of belts plus fabric. Other ways of pressuring the fabric passing through the machine could however be employed. One roller of a nip could be fixed and the other pressured to squeeze the fabric. Both rollers of the nip could be tied to a nominal minimum nip gap, but one could be movable to accommodate variations on the thickness of the fabric and belt. If desired, the fabric could be squeezed simply by tensioning the endless belts appropriately.

It should be understood that the word fabric has been used in the speci'ication in its broadest sense and includes in addition to textile sheet material of the woven, non-woven or knitted types other types of sheet material shuch as synthetic plastics, for example, polyvinyl chloride (PVC) and polyurethane; leather, felt, rubber and paper or combinations thereof.

Claims

1. A fabric production, treatment or finishing machine comprising a plurality of guide rollers disposed to provide two endless paths each having a common section passing over a heatable curved treatment surface, two endless belts disposed for movement around respective endless paths, and means for feeding in a fabric to be treated on the treatment surface so that the fabric is received between the belts during its passage over the surface, the arrangement being such that fabric can be successively heated and cooled whilst sandwiched between the belts.

2. A fabric production, treatment or finishing machine as claimed in Claim 1, in which the curved treatment surface is constituted by the surface of a heatable treatment roller.

3. A fabric production, treatment or finishing machine as claimed in Claim 2, in which there is an unheated treatment roller disposed downstream of the heatable roller and lying on the common section.

4. A fabric production, treatment or finishing machine as claimed in Claim 3, in which the heatable and unheated rollers are arranged relative to one another to define a nip therebetween lying on the common section.

5. A fabric production, treatment or finishing machine as claimed in Claim 1 or 2, in which there are two heatable rollers disposed adjacent each other to define a nip lying on the common section.

6. A fabric production, treatment or finishing machine as claimed in Claim 5, in which there is an unheated roller lying downstream of the heatable rollers on the common section.

7. A fabric production, treatment or finishing machine as claimed in Claim 2 or in any of claims 3 to 6 when appendant directly or indirectly to Claim 2, in which there are three pairs of treatment rollers.

8. A fabric production, treatment or finishing machine as claimed in Claim 7, in which two of the three pairs of rollers are heatable.

9. A fabric production, treatment or finishing machine as claimed in any preceding claim, in which the or each heatable curved treatment surface is oil or steam heated.

10. A fabric production, treatment or finishing machine as claimed in any preceding claim, in which the means for feeding in a fabric comprises a take-off roller.

11. A fabric production, treatment or finishing machine as claimed in any preceding claim, in which the endless belts are coated with a low friction material.

1 2. A fabric production, treatment or finishing machine as claimed in Claim 11, in which the belts have a woven glass fibre base with a silicon rubber coating.

1 3. A fabric production, treatment or finishing machine as claimed in Claim 11, in which the belts have a woven glass fibre base with polytetrafluoroethylene coating.

14. A fabric production, treatment or finishing machine as claimed in any preceding claim, in which apparatus is provided for coating the fabric before entry into the treatment rollers.

1 5. A fabric production, treatment or finishing machine as claimed in any preceding claim, in which a reel-up roller is provided to receive the fabric after leaving the common section.

1 6. A fabric production, treatment or finishing machine as claimed in Claim 2, or in any of Claims 3 to 1 5 when appendant directly or indirectly to claim 2, in which one or one or the treatment roller is directly driven and any other treatment rollers are indirectly driven from that directly driven treatment roller.

1 7. A fabric production, treatment or finishing machine as claimed in Claim 16, in which the reel-up roller is directly driven or indirectly driven from the driven treatment roller.

1 8. A fabric production, treatment or finishing machine as claimed in any preceding claim, in which one or both belts may be in the form of a lattice.

1 9. A fabric production, treatment or finishing machine as claimed in Claim 5 or 6 or in any of Claims 7 to 1 8 when appendant directly or indirectly to Claim 5 or 6, in which the nip is fixed and has a dimension less than the sum of the thicknesses of the two endless belts and the fabric passing therethrough in operation of the machine.

20. A fabric production, treatment or finsihing machine as claimed in Claim 5 or 6 or in any of Claims 7 to 1 8 when appendant directly or indirectly to Claim 5 or 6, in which one of the rollers defining the nip is fixed and the other is movable and can be pressured to squeeze the belts and fabric passing therethrough during operation of the machine.

21. A fabric production, treatment or finishing machine as claimed in Claim 5 or 6 or in any of Claims 7 to 1 8 when appendant directly or indirectly to Claim 5 or 6, in which the nip is nominally fixed but one of the rollers defining the nip is movable so that it can adjust to varying thicknesses of belt and fabric passing therethrough during operation of the machine.

22. A fabric production, treatment or fin ishing'machine as claimed in any preceding claim, in which the belts are tensioned to squeeze the fabric during operation of the machine.

23. A fabric production, treatment or fin ishing machine as claimed in any preceding claim, in which those parts of the machine supporting the endless belts are cantilevered to facilitate removal and replacement of the belts.

24. A fabric production, treatment or fin ishing machine substantially as hereinbefore described with reference to Fig. 1 or Fig. 2 of the accompanying drawings.

25. A method of producing, treating or finishing a fabric including the steps of sand wiching a fabric between two belts of mate rial, passing the sandwich so formed over a heated curved treatment surface so as to heat it, cooling the sandwich to cool the fabric, and then removing the fabric from between the two belts.

26. A method of producing, treating or finishing a fabric as claimed in Claim 25, in which the heated, curved, treatment surface is constituted by the surface of a roller which defines a nip with another roller through which the belts fabric sandwich is passed.

27. A method of producing, treating or finishing a fabric as claimed in Claim 25 or 26, in which the sandwich is cooled by pass ing it over an unheated roller.

28. A method of producing, treating or finishing a fabric substantially as hereinbefore described with reference to Fig. 1 or Fig. 2 of the accompanying drawings.

29. A fabric produced, treated or finished on the machine claimed in any of claims 1 to 24 or by the method claimed in any of claims 25 to 28.

30. A fabric production treatment, or fin ishing machine comprising a plurality of treat ment rollers, including a pair of adjacent heated rollers, an unheated roller downstream of the heated rollers, a plurality of guide rollers disposed in relation to the treatment rollers to provide two endless paths each having a common section passing between adjacent heated treatment rollers, two endless belts disposed for movement around respective endless paths, and means for feeding in a fabric to be treated to the treatment rollers so that the fabric is received between the belts during its passage through the treatment rol lers.

31. A method of producing, treating or finishing a fabric including the steps of sand wiching a fabric between two belts of mate rial, passing the sandwich so formed through -the nip formed between two heated rollers so as to heat it, subsequently passing the sand wich over at least one cold roller and then removing the fabric from between the two belts.