Classifications

• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
  • D04H1/4209—Inorganic fibres
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
  • D04H1/4209—Inorganic fibres
  • D04H1/4218—Glass fibres
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
  • D04H1/4209—Inorganic fibres
  • D04H1/4218—Glass fibres
  • D04H1/4226—Glass fibres characterised by the apparatus for manufacturing the glass fleece
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/70—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
  • D04H1/72—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
  • D04H1/736—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged characterised by the apparatus for arranging fibres
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/70—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
  • D04H1/74—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being orientated, e.g. in parallel (anisotropic fleeces)

Definitions

• the present invention relates to a method and an apparatus for the treatment of a mineral fibre felt for the purpose of re-orienting the fibres in the felt, by successively changing the speed of the felt during its transport through a transport apparatus.
• Mineral wool products of glass wool, rock wool and slag wool type are the most well known and used products for both heat insulation and acoustical insulation.
• These products are commonly made by melting the raw material, forming fibres from the mineral melt e.g. by feeding it to a spinning unit, which can consist of a number of rotating wheels, carrying the fibres formed with an air current from the spinning unit and collecting them onto a conveyor in the form a fibre felt.
• the collecting can take place either so that the fibres are collected onto the conveyor to form a felt of the desired end thickness, or by forming a so-called primary web by collecting a thin layer of fibres, which thereafter, e.g. by means of a pendulum conveyor, is folded to form a secondary felt of the desired thickness.
• the felt is impregnated with a suitable binder, e.g. a resin, which at a final stage of the treatment of the felt is cured by heat treatment, e.g. in an curing oven, whereby the fibres are fixed to each other and form a dimensionally stable continuous felt of desired density and thickness. Thereafter the felt is cut to the desired shape, either in the form of sheet type products or roll products, which are then packed or processed further.
• a suitable binder e.g. a resin
• the fibres When the fibres are collected from the spinning unit, either in the form of a primary web, or in its final thickness, the fibres are received on the conveyor substan ⁇ tially in a plane parallel to the conveyor, i.e. only a small amount of the fibres will be oriented in a direction which is more or less perpendicular to the plane of the conveyor.
• This-phenomenom is of advantage in some fields of application, as such products exhibit good elastic proper ⁇ ties, but are of a great disadvantage in other.
• This structure of the felt results in particular in poor strength characteristics in a direction perpendicular to the felt plane, wherefore such products cannot be used in constructions which are subject to great mechanical loads, e.g. in floors, or in ceilings under load.
• One way of achieving sufficient mechanical strength in a direction against the felt plane is to increase the volume weight, i.e. the density of the felt, hich can be done by increasing the fibre amount, or in some cases, the amount of binder.
• the manufacturing costs are, however, directly proportional to the fibre weight, wherefore increasing the strength by increasing the amount of fibre can be economi ⁇ cally unacceptable in some cases.
• Increasing the strength in a direction perpendicular to the felt plane can also be achieved by changing the direction of the fibres in the felt so that a greater fraction of these are arranged in a direction which deviates from the felt plane. This can be accomplished in many ways.
• a third way of changing the major fibre direction in the felt has been described in DE A 16 35 620.
• the rate of progress of the felt is decelera ⁇ ted between two successive conveyors by running the back conveyor, as viewed in the direction of movement, at a lower speed than the preceeding one.
• This braking effect results in a longitudinal compression with a re-orientation of the fibres within the felt, without the formation of creases on the surface.
• good results are achieved as regards both the mechanical and insulating properties of the final product, provided the degree of compression, i.e. the speed reduction of the felt during the treatment, is kept below about 30 %. If the degree of compression is higher, creases begin to appear on the surfaces of the felt.
• the present invention aims at overcoming the disadvantages associated with the known apparatuses, especially the uncontrolled treatment of the felt at a few forceful separate locations acting over the width of the felt. Namely, in accordance with the method and the apparatus according to the invention, a controlled and fine-structu ⁇ red re-orientation of the fibres takes place in the felt as a result of a substantially continually controlled change of speed of the felt, without formation of creases and in a single treatment stage, which easily can be incorporated into existing manufacturing lines.
• the change of speed of the felt is effected by bringing the felt into contact with at least two elements arranged successively in the transport direction of the felt, the areas of influence of the elements overlapping each other.
• the change of speed of the felt over all the elements is preferably negative, i.e. the exit speed of the felt from the last element is lower than its speed before the first element.
• the elements are of such a shape and mutual arrangement that the border or border zone where the influence of one element on the felt is greater than that of the adjacent element, is a substan ⁇ tially waveshaped line, extending over the width of the felt.
• the said element is preferably comprised of a pair of shafts extending across the felt, one shaft on either side of the felt rotating in a direction towards each other.
• the shafts are provided with means which come into contact with the felt and which affect the advancing speed of the felt, that is, depending on the rotational speed of the shafts in relation to the advancing speed of the web, they can exert a braking or an accelerating effect on the felt, leading to a re-orientation of the fibres.
• the shafts are arranged in such a manner that when the felt is transported through a number of consecutive elements, the areas of influence on the felt of two consecutive elements overlap or mesh. It is assumed that it is this overlapping of the areas of influence of the elements, i.e. the continuous effect of the elements on the felt, which leads to the advantageous end result, in contrast to the shocking impact-like treatment according to the known technique.
• a treatment zone can be defined as an area where one element has a greater influence on the felt than the adjacent element(s).
• the rate of progress of the felt just in front of an element is completely governed by the said element, but the effect on the advancing speed is thereafter gradually shifted to the next element. At some point between these elements the speed is governed more by one element than the other.
• the area of influence of each element overlaps or meshes with the area of influence of an adjacent element, every cross- section of the felt is always within a treatment zone, where it is subject to and affected by at least one element.
• the felt is preferably subjected to a treatment over a number of, e.g. 4 to 12 elements.
• the felt is subjected to a decrease in speed over the whole length of the transport apparatus which decrease preferably is continuous and uniform, i.e. there is an equal decrease in speed from element to element, which preferably is about 10 to 20%.
• the change in speed does not, however, need to be uniform, but it can be advantageously of different magnitude at different stages of the treatment.
• the decrease in speed from element to element can thus be smaller in the beginning and bigger towards the end of the treatment, or the difference in speed between two consecutive zones can be substantially bigger than between the other zones. In this case such a more forceful treatment takes advantageously place in the later part of the apparatus. It is, however, also possible to increase the speed of the felt in one or some of the treatment zones, provided that the treatment leads to an end product with re-oriented fibres.
• An acceptable product, without crease formation, is obtained according to the invention if the felt is subjec ⁇ ted to a treatment which results in varying degrees of compression, but preferably a degree of compression is used which is about 2:1 to 10:1, especially 3:1 to 6:1, which corresponds to a speed reduction of about 50 to 90%, especially about 70 to 80%.
• the felt prior to the treat ⁇ ment, is precompressed in a direction perpendi ⁇ cular to the main plane of the felt to a thickness less than that of the felt after the treatment.
• Precompression of the felt for example to about 70% of the final thick ⁇ ness, and expansion thereof during the treatment, allows for a greater degree of compression without giving rise to non-uniformities in the surface layer and inner layer, respectively, of the felt, i.e. without the formation of a so-called arrow-shaped fibre structure in a cross-section of the product. This has been an additional problem associated with a high degree of compression according to the prior known methods.
• the invention relates also to an apparatus for carrying out the method.
• the apparatus comprises in its simplest form a transport apparatus with two conveyors facing each other and between which the fibre felt is transported, whereby each conveyor comprises at least two shafts which can be driven with different rotational speed, the shafts carrying means to be brought into contact with that surface of the felt facing the respective conveyor, the areas of influence of the shafts on the felt overlapping each other.
• the shafts in a conveyor can be driven at different rotational speeds, whereas a pair of shafts which is formed by mutually facing shafts in separate conveyors, is always driven at the same speed, but in opposite direction.
• the shaft carries a number of means arranged in a mutually spaced relationship on the shaft, which means on one shaft are directed towards and extend into the spaces between the means on an adjacent shaft.
• the means on one shaft in one conveyor form a nip for the felt with the corresponding means on a shaft in the other conveyor, but they can also be directed towards the spaces between the means in the last mentioned convey ⁇ or.
• the transport apparatus contains preferably 4 to 12 shafts in each roller conveyor thus forming the same number of shaft pairs.
• the means which come into contact with the felt can be of any suitable design, they can e.g. have the shape of paddles, needles, plates, flanges or the like, or they can be shaped as short endless conveyor belts arranged in a mutually spaced relationship across the width of the felt and extending in the transport or longitudinal direction of the felt, and they may carry formations for increasing the friction, such as spikes or the like.
• the shafts In order to make it possible to convert the apparatus for the manufacture of products of different type, it is advantageous to provide the shafts with means for indepen ⁇ dent variation of the rotational speed of the shafts.
• the design of the driving means is known technique for a person skilled in the art.
• the conveyors can be provided with per se known means for adjusting the distance between and/or the mutual inclination of the conveyors.
• the treatment in such cases can be made with simultaneous thickness compres ⁇ sion or expansion of the felt, the re-orientation condi ⁇ tions of the fibres can be further modified and thus the treatment adjusted for highly varying product types.
• the distance and/or the degree of inclination may also be varied along the length of the transport apparatus.
• Figure 1 illustrates schematically an apparatus for making a fibre felt which includes an apparatus for the treatment of the felt according to the invention
• Figure 2 illustrates schematically two co-operating roller conveyors forming the apparatus for treatment of the felt, viewed from the side,
• Figure 3 illustrates schematically the principle for an embodiment of co-operating shafts in a roller conveyor, in a plan view
• Figure 4 shows an element formed by a pair of shafts viewed in the direction of progress of the felt
• Figure 5 shows an embodiment of the means intended to come into contact with the felt.
• Figure 6 illustrates schematically the apparatus with variable distance and inclination between the conveyors
• Figures 7a to 7d show different speed profiles of the felt during its transport through the transport apparatus.
• Figure 1 illustrates schematically the treatment of a fibre felt which in the form of a primary felt 1 is transported from a spinning unit, not shown, and folded to form a secondary felt 3 of desired thickness.
• This secondary felt 3 is thereafter fed in between two rolls 4, 4', which cause the felt 3 to be precompressed in a direction perpendicular to the plane of the felt.
• the felt is compressed to a thickness which is less than the thickness of the felt after the treatment, and suitably to about 70% of the final thickness of the felt.
• the felt is fed, suitably over guiding means into a transport apparatus for the treatment according to the invention, which apparatus as a whole is designated with the reference numeral 8.
• the transport apparatus 8 comprises an upper and a lower conveyor 9 and 10, respecti ⁇ vely, which both in the embodiment shown have a number of rolls in the form of cam shafts, whereby two mutually opposite cam shafts 11 and 11', 12 and 12', etc. form a cam shaft pair, which together define nips 11a, 12a etc. for the felt.
• the speed of the conveyors decreases in the direction of progress of the felt due to the fact that the cam shaft pairs rotate with gradually decreasing rotational speed.
• a suitable speed reduction between two successive shafts is 10 to 20%.
• the first two pairs of shafts can have the same rotational speed as the speed of the conveyor preceeding the transport apparatus, whereas the speed thereafter is gradually reduced as has been mentioned, at successive shafts and the last few shafts in the apparatus can have the same speed as the conveyor in the curing oven.
• FIG. 3 shows schematically how the cam shafts can be designed and co-operate in one conveyor, illustrated in a plan view.
• the direction of progress of the felt between the shafts is illustrated with an arrow.
• each cam disk 16 on a cam shaft extends into the space between two cam disks 16" in the adjacent cam shaft.
• the cam shafts have a center distance (a) which is about 70% of the disk diameter of the cam shaft disks, the width (b) of the disks being about 30% of the center distance, and the interspace (c) about 40 to 50% of the center distance.
• the nip 17 for a few adjacent cam disks have been indica ⁇ ted.
• the nips between the cam shafts result in this embodiment in substantially linear contact areas with a restricted dimension primarily in the transverse direction of the felt, two subsequent cam shaft nips forming contact areas of a zig-zag design across the width of the web.
• the Figure 4 shows a treating element comprising a pair of shafts with the same rotational speeds rotating in opposite directions and viewed in the direction of progress of the felt.
• the solid lines refer to the embodiment according to the invention where the cam disks 16 in each conveyor are directed towards each other forming a nip 17.
• an alternative embodiment is shown with dotted lines where the cam disks in each conveyor are not directed towards each other, but the cam disk in one conveyor is facing the interspace between the cam disks in the other conveyor.
• FIG. 5 An embodiment for the means intended for contact with the felt is illustrated in the Figure 5, which shows a plate 16 mounted on a shaft which plate on its outer periphery is provided with a number of flanges 18 distributed evenly around the circumference.
• Figure 6 shows schematically an embodiment where the upper conveyor is divided into two parts 9a, 9b.
• the first part 9a is arranged in an inclined manner with respect to the lower conveyor 10.
• Figures 7a to 7d alternative embodiments for the speed profile of the felt during the treatment according to the invention are shown.
• Figure 7a shows the case where the felt is subjected to a uniform speed reduction over all the elements in the apparatus.
• Figure 7b shows the case where the speed reduction is less at the beginning part of the treatment, and bigger towards the end, whereas the Figure 7c shows the case where the biggest speed reduction takes place in the middle of the treat ⁇ ment.
• the Figur 7d shows the case where the speed of the felt is also allowed to increase at one or several elements.

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Inorganic Chemistry (AREA)
• Manufacturing & Machinery (AREA)
• Nonwoven Fabrics (AREA)
• Compression Or Coding Systems Of Tv Signals (AREA)
• Mobile Radio Communication Systems (AREA)
• Treatment Of Fiber Materials (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=8530124

Family Applications (1)

Country Status (7)

Families Citing this family (10)

Family Cites Families (2)

• 1990
  • 1990-03-26 FI FI901486A patent/FI85034C/sv not_active IP Right Cessation
• 1991
  • 1991-03-22 JP JP91505755A patent/JPH05506891A/ja active Pending
  • 1991-03-22 RU SU915053204A patent/RU2054067C1/ru active
  • 1991-03-22 WO PCT/FI1991/000078 patent/WO1991014816A1/en not_active Application Discontinuation
  • 1991-03-22 EP EP91905949A patent/EP0521905A1/en not_active Withdrawn
  • 1991-03-22 CA CA002078988A patent/CA2078988A1/en not_active Abandoned
  • 1991-03-26 CZ CS91817A patent/CZ279379B6/cs unknown

Non-Patent Citations (1)

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