EP0088213A2 - Method of making a non-woven pile fabric by needling - Google Patents

Abstract

1. A method of manufacturing a pile nonwoven by structure needling, wherein at first a fibre fleece is produced and prebonded as by needling, thereafter, this nonwoven fabric is passed over a laminated grate of lamellar webs aligned in the direction of fabric travel and having gaps interposed therebetween, while it is projected in cycle by lifting needles in serial arrangement aligned with the gaps, and upon projection the bundles of fibre seized by each row of needles are pressed into the gaps of the laminated grate and produce pile knops projecting from the fabric bottom on a respective fabric strip extending in the direction of fabric travel, whose knop density is dependent on the working cycle of the needles, the needle density and the rate of travel of the fabric, this structured fabric is finally coated with a bonding agent and the tips of the pile knop fleece are clipped on the fabric front, if necessary, characterized in that in adjacent fabric strips (27, 27') the pile knops (26, 26') are produced in respective alternating strips and in chronological order in two different serially arranged projection fields (11, 11'), wherein the respective lamellar webs (13, 13') in one field (11, 11') are aligned with the gaps (14, 14') in the other field (11, 11').

Description

The invention relates to a method for producing a pile fleece covering by means of structural needling. For this purpose, a preliminary product is first produced, consisting of a nonwoven fabric that is pre-consolidated by needling. The structural needling is carried out by guiding the pre-fabric over a lamella grate from lamella webs oriented in the direction of the goods flow with gap gaps in between and intermittently piercing the pre-fabric with lifting needles that are aligned in rows with the gap gaps. The flocks of fibers grasped by each row of needles are thereby pushed into the gap gaps of the slatted grate and produce pimples protruding from the base of the goods on a strip of goods extending in the direction of movement of the goods. The knob density generated in a strip of goods depends on the working cycle of the needles and the speed of the goods. This is how the structural goods are made, which are treated with binders on the back of the goods in order to solidify the goods base. In order to give the textured goods a velor character, the tips of the polnubs are shorn on the front of the goods.

In this known method, because of the row-by-row arrangement of the needles, a rib structure of the pole knobs is formed, which extends in the direction of the goods pass. The goods get a cord-like appearance. The rib-forming pole knobs lie one behind the other in the direction of the ribs and can support one another, but there is a rib spacing transversely to this, which precludes such support here. Because of this rib structure, the goods also have different elongation characteristics in the longitudinal and transverse directions, which can impair the dimensional accuracy of the end products produced from this pile fleece. This is important because after being deformed and punched according to the contours, such fleece coverings are used for the interior of vehicles. The rib structure also has an adverse effect on the imprinting process of this known covering; when walking on or after pressure, there is a high permanent settling of the pole knobs, which does not easily reform itself.

An improvement could undoubtedly be achieved if the ribs could be placed closer together and a lot of fiber material would be lifted out when the needle was pierced to form the pile nubs. But there seems to be an insurmountable limit. The needles in adjacent rows cannot be placed closer together than the width of the lamellar webs between them allows. Because the slat gratings have to take up considerable structural needles and the straight position of the individual slat webs must be guaranteed, a certain minimum remaining width of the slat webs must not be undercut; the slat web cannot be set to a zero width In addition, according to relevant experience in practice, apart from the strength considerations, the web spacing cannot equally be made arbitrarily small. On the basis of a lamella division of 3 mm, if the web spacing is reduced by a tenth, the fiber material that is removed when the needle is pierced is reduced by a considerable percentage. The free space between the lamella webs and the needle shaft determines the volume of the fiber material that is removed when the needle is pierced. By reducing the pitch of the slatted frame and reducing the needle size, a usable pile fleece with a rib structure can no longer be produced economically.

The present invention has for its object to develop a simple and inexpensive method for producing a pile fleece covering of the type described above, in which, however, a good support of the generated pile knobs is ensured, the impression behavior is improved and the product is advantageously dimensionally stable.

This is achieved according to the invention in that in contiguous strips of product the pimples are alternately produced one after the other in strips in two locally located needle piercing fields one after the other, the lamellar webs in one field being aligned with the switching gaps in the other field.

Without jeopardizing the strength and rigidity of the lamellar webs, the pole knobs in the adjacent ear strip can now be placed so tightly that they can support each other with their bulk not only within a strip of goods, but also across it, towards the neighboring strip. The slat webs run in the grate in the invention, not in a straight line, but are divided into two or more fields that are cross-offset to each other, where, if you look in the direction of the goods flow, they are alternately arranged with gaps in the gap, where there are free spaces in a field, because there are lamella webs are located, the knobs are being molded in a subsequent other field, while the knobs previously created are supported in this working phase on the lamellar webs there. By coordinating the throughput speed and the arrangement of the needles in the various fields, it can be controlled that the pole knobs of a strip of goods are aligned approximately aligned with the free spaces of an adjacent strip of goods, which is particularly favorable for mutual support. Because of the oriented puncture of the needles in the different fields, it is important to form the pimples - with a local offset - but at the same time and in the same cycle.

The result is a covering that no longer has a recognizable rib structure. This also leads to a leveling of the product, which is reflected in a high degree of dimensional accuracy. The pole knobs are so well supported against each other that ideal impression behavior is achieved with this covering according to the invention.

• Fig.1 in schematischer, perspektivischer Darstellung die Ansicht auf eine Vorrichtung, mit der das erfindungsgemäße Verfahren ausführbar ist,
• Fig.2 die Draufsicht auf einen Lamellenrost in ungefähr maßstabsgerechter Ausführung,
• Fig.3 u.4 in Vergrößerung Bruchstücke der Querschnittsansichten durch eine solche Vernadelungsstelle längs der Schnittlinien III-III bzw. IV-IV von Fig.2,
• Fig.5 in schmatischer Weise und Vergrößerung die Draufsicht auf einen bekannten Polvliesbelag, wozu in Fig.6 die Anordnung und Ausbildung des Lamellenrostes und der Nadeln gezeigt sind,
• Fig.7 in entsprechener schematischer Darstellung die Draufsicht auf einen erfindungsgemäßen Belag, der unter ähnlichen Bedingungen, wie diejenigen von Fig.5, erzeugt wurde, wobei in Fig.8 die besondere Anordnung und Lage des Lamellenrostes und sowie der zugehörigen Nadeln angedeutet ist und
• Fig.lo die Draufsicht auf ein weiteres Ausführungsbeispiel des erfindungsgemäßen Polvliesbelages, der in einer gegenüber Fig.7 dichteren Strukturvernadelung ausgeführt worden ist, wobei in Fig.lo der gleiche maschinelle Aufbau der Arbeitsmittel wie in Fig.8 zu erkennen ist.

The invention is shown in several exemplary embodiments in the drawings. Show it:

• 1 shows a schematic perspective view of a device with which the method according to the invention can be carried out,
• 2 shows the top view of a slatted grate in an approximately true-to-scale design,
• 3 and 4 on an enlarged scale fragments of the cross-sectional views through such a needling point along the section lines III-III or IV-IV of FIG. 2,
• 5 shows a top view of a known pile fleece in a schematic manner and on an enlarged scale, for which purpose the arrangement and design of the slatted frame and the needles are shown in FIG. 6,
• 7 in a corresponding schematic representation, the top view of a covering according to the invention, which was produced under similar conditions to those of FIG. 5, the special arrangement and position of the slatted frame and the associated needles being indicated in FIG
• Fig.lo the top view of a further embodiment of the pile fleece covering according to the invention, which has been carried out in a structural needling denser compared to Fig. 7, wherein the same mechanical structure of the work equipment as in Fig. 8 can be seen in Fig.lo.

The starting product for the pile fleece covering according to the invention are staple fibers. They are rolled up as a pile with the help of a cross-layer several times layered and mechanically consolidated into a pre-fleece by needling. Such preliminary goods 10 are now subjected to a special structural needling, which is to be described in more detail with reference to FIGS. 1 to 4, where the most important mechanical components for implementing the method are shown.

The treatment takes place in two fields 11, 11 ', which are realized here in two sections of a lamella grate 12 lying one behind the other. An alternative would be to divide the two fields into several individual sections that lie in an alternating order. In each field 11, 11 'there are lamellar webs 13, 13', which are at a defined distance from one another and therefore close gap gaps 14, 14 'between them. The lamellar webs 13, 13 'serve as a support surface when carrying out the preliminary goods and extend in the direction of the goods pass 15, which is marked in FIG. 1 by an arrow. In each field 11, 11 'there is a bevy of structural needles 16, e.g. in the form of fork needles, which therefore have a fork opening instead of a tip, but each form a row 17, 17 ', which are arranged in the two fields 11, 11' with a lateral offset 18 according to FIGS. 1 and 3 are. This results because each row of needles 17 and 17 'is aligned with one of the gap gaps 14 and 14' in the associated fields 11, 11 '. The peculiarity lies in the fact that the lamella webs 13 of one field 11 are aligned with the gap gaps 14 ', as is shown by the assignment arrows 19 in FIG. 1; and vice versa, the webs 13 'of the rear panel 11' are aligned with the gap gaps 14 of the front panel 11. In the arrangement 17, 17 'described, all the needles 16 are jointly movable in a stroke - in the sense of the movement arrow 21 shown in FIGS. 3 and 4 - in a needle bar 20.

In the upper reversal point of the reciprocating motion 21, which is shown as in the Figures 3 and 4, are the Gebel ends 22 of the needles 16 outside of the web 1 ₀ and engage through, openings 23, arranged above the web 1o stripper plate 24. In another implementation of the Lifting movement 21, the leg ends 22 pass through the openings 23 of the stripping plate 24, bump into the fleece 1 ₀ , capture a hinge of fibers of the preliminary fleece on the way of their piercing movement and press it out on the underside 25 of the fleece 1 ₀ , into the gap gaps 14 of the Lamellar grating 12 in this first field 11. This results in the pole knobs 26 indicated in FIG. 3, which come to rest in a fabric strip 27 best seen in FIG. By changing the penetration depth 21 of the needles 16, the height of the knobs 26 can be influenced, which is usually in the range from 4 mm to 8 mm. The thickness 28 of the needles 16 in the shaft area is 1 mm. The division in the grate 12 is only 3 mm, with 1 mm for the width of the respective web 13 or 13 'and 2 mm for the clear width 29 of the gap gap 14 or 14'. 1, 3 and 4 are therefore not drawn to scale. For reasons of strength, the web width 31 indicated in FIG. 3 cannot be selected to be smaller, nor should a division of less than 3 mm, indicated in FIG. 3, of approximately 3 mm be used, so that, starting from the structural needle 15, one that is necessary for reasons of strength Strength 28 still acceptable amounts of fiber material detected and pressed out to the knob 26. With narrower divisions 3o, the knobs are too weak.

5 shows a section of a known structural product 32, which is generated by a continuous row 17 of structural needles 16, which are not in the different fields 11, 11 ', which are characteristic of the invention, but are designed to be continuously aligned. In coordination with the feed 15 in the goods, the number of needles and the needle spacing, a rib structure 33 results in the relevant product strip 27, in which the nub density within the rib 33 depends on the aforementioned operating sizes. In this known pile fleece covering 32, the spacing sequence 34 is satisfactorily narrow, as is indicated by the fiber pad 35 indicated by circular lines in FIG. 5, which forms the pressed-out pile studs 26 on the underside of the goods. The puncture area of the needle is marked there as a central circular disk 36. Because of the gap gap 14 delimited by the webs 13 in the direction of passage 15 of this article 32, the outline of the fiber bundle 35 detected during the needling of the structure is oval, with an axis oriented in the direction of the article passing through. In the direction of the ribs 33, the tufts 35 are adequately supported at the selected knob density 34, but empty lanes 37 are formed between the ribs, where the ribs 33 are at a distance 38 from one another, which provides effective mutual support of the pole knobs 26 with respect to the Excludes goods width. The known goods 32 do not behave favorably under pressure. The properties of the goods to tensile stress in the longitudinal and transverse directions 39 4 _0, each indicated by the arrows in Figure 5 are different, which would lead to poor dimensional stability of the goods 32nd

6 shows in cross section the structure of the slatted frame 12 in a front and a rear section, the same being used to designate corresponding components Reference numerals, as in the previous description of the invention according to Fig.1 to 4, have been used. It can be seen that the disturbing lane formation 37 is caused by the inevitable web width 31 of the uniform lamella grate 12. It is not possible to bring these web widths 31 to zero in order to reduce the disturbing distance 38.

In the method according to the invention, however, there are two types of needle puncture fields 11, 11 'because, as has already been mentioned at the beginning, the lamella grate 12 has a special structure. 2 shows, approximately in natural size, the arrangement of the needles, webs 13, 13 'and gap gaps 14, 14' in the two fields 11, 11 '. What is achieved in field 11 has been described above in connection with FIG. 3; Now the treatment of the goods in field 11 'has to be described in addition.

Here are the conditions of Fig.4. Because of the offset 18 of the two rows of needles 17, 17 'in the fields 11, 11' already explained in connection with FIG. 1, pimples 26 'are now formed which, as shown in FIG. 7 with the aid of a section of the nonwoven covering 41 according to the invention, in the intermediate strips 27 'are arranged, which remained unprocessed in the previous treatment in the field 11 because they were in the area of the webs 13 there. But now they are located within the gap gaps 14 'and interact there with the rows of needles 17'. A comparison with FIG. 5 shows that the same puncture density as in the known article 32 of FIG. 5 is present in FIG. 7, but a significantly different and cheaper division is achieved. In Figure 7, these relationships are based on the same symbols as in Fig. 5 clarifies why we have used the same reference numerals. The tufts of fibers 35 generated due to the central punctures 36 of the needles in the fabric strip 27 formed in the field 11 are supported in all four directions by fiber bulbs 35 'which arise in the fabric strip 27' lying on both sides thereof when the other field 11 'is created. In the longitudinal and transverse directions 39 ', 4o' of FIG. 7 there is now the same structure which leads to properties of the covering 41 which are balanced on all sides. Perfect dimensional accuracy is obtained. The pressure behavior of the goods is good because of the all-round support.

FIG. 8 again illustrates in cross section the conditions in the two fields 11, 11 ', as have already been described in connection with the preceding FIGS. 1 to 4. These conditions also exist when the pile fleece covering 42 according to the invention is produced according to FIG. 9, as can be seen from the identical structure of these components between FIGS. 8 and 10.

The Fig.7 was developed from the needle penetration density, as has been explained, from Fig.5. While it does not make sense according to FIG. 5 to achieve a greater nub density by reducing the spacing sequence 34 of the needle punctures 36 - because only the rib structure 33 would be more pronounced - the situation is different according to FIG. 7. 35 ', because of the low knob density selected here, free spaces 43 are formed, if desired, could easily be reduced or even completely eliminated by a higher knob density in the inventive strips 27, 27'. The latter is shown in Fig.9. Because of the same structure in the slats rust 12 and in the arrangement of the two rows of needles 17, 17 ', the width of the aforementioned strips 27, 27' is the same as in Fig. 7. Due to a lower throughput speed 15 of the goods 42, a higher work cycle or a larger needle density, the spacing sequence 44 of the knobs 26 or 26 'in a goods strip 27 or 27' is brought to the smaller value 44 ', so that there is no horizontal support only in four directions but a mutual contact of the molded-out pole knobs 26, 26 'results all around. The dimensional accuracy is consistently good due to the uniform construction on all sides. The impression behavior of the covering 42 is almost ideal. If the tips of the pile nubs 26, 26 'are cut off, so that the fiber ends are exposed to the face, one has the impression of a closed velvet-like velor. There is no longer any evidence of rib formation.

In the example of FIGS. 1 and 2, the two lamella web sections 13, 13 'are supported by a central frame spar 45, as is done by the end spars 46, 47. The central spar 45 results in a particular stability in the central area and also ensures a perfect offset 18 of the webs 13, 13 'on both sides. It is important to bring the two fields very close together. As already mentioned, the two fields 11; 11 'are divided into sections and connected in series with one another in an alternating sequence. For an exact puncture sequence, it is important to make the punctures in the two fabric strips 27, 27 'as closely as possible one after the other and for this purpose to use a needle bar 20 which can be moved up and down and which positions the individual needles 16 exactly with respect to one another. The aim is seen the knobs 26 'in the transverse direction 4 ₀ `possible to gap 48, 43 with the knobs 26 'of the adjacent fabric strip 27. Instead of the central frame spar 45, the webs 13, 13 'on both sides could also be gripped directly between one another and thus fastened to one another. In the latter case, the web then forms the clear width of the gap gap in the adjacent field.

Reference symbol list

• 10 goods, fleece
• 11 front field
• 11 'rear Eeld
• 12 slatted frame
• 13 slat web at 11
• 13 'slat web at 11'
• 14 gap gap at 11
• 14 'gap gap at 11'
• 15 Direction of goods flow
• 16 structure needle
• 17 row of 16 at 11
• 17 'row of 16 at 11'
• 18 offset from 17, 17 '
• 19 assignment arrows
• 2o needle bar
• 21 movement arrow of 20
• 22 fork end of 16
• 23 opening of 24
• 24 scraper plate
• 25 bottom of 10
• 26 Polnoppe at 11
• 26 'Polnoppe at 11'
• 27 strips of goods
• 27 'intermediate strip of goods
• 28 needle size
• 29 clear width of 14, 14 '
• 3o division of 12
• 31 web width
• 32 previously known goods
• 33 rib
• 34 Distance sequence, nub density
• 35 fiber bulk
• 35 'fiber bulk
• 36 central circular disc
• 37 empty alley
• 38 distance from 33
• 39 longitudinal direction at 32
• 39 'Longitudinal direction at 41
• 40 transverse direction at 32
• 40 'transverse direction at 41, 42
• 41 fleece covering
• 42 fleece covering
• 43 vacancies
• 44 distance sequence at 41
• 44 distance sequence in 42
• 45 middle frame spar
• 46 end spar
• 47 end spar
• 48 hatch between 26 in 27

Claims (3)

1.) Process for producing a pile fleece covering by means of structural needling, a fiber fleece first being produced and pre-consolidated by needling, this pre-fabric is then guided over a lamella grate from lamella webs oriented in the direction of the goods pass with gaps in between and is expelled in the cycle by needles which can be moved and are aligned in rows with the gap gaps, when ejecting, the fiber balls grasped by each row of needles are pressed into the gap gaps of the slatted grate and produce pimples protruding from the fabric base on a fabric strip extending in the direction of the fabric flow, whose knob density depends on the working cycle of the needles, the needle density and the throughput speed of the goods, this structured product is finally on the back of the product Binder is applied and, if necessary, the tips of the pile of pimples are shorn on the front of the goods, characterized , that in adjacent strips of goods (27, 27 ') the pimples (26, 26') are alternately produced in strips one after the other in two, locally successive ejection fields (11, 11 ') the lamella webs (13, 13 ') in one field (11, 11') being aligned with the gap gaps (14, 14 ') in the other field (11, 11'). 2. The method according to claim 1, characterized in that that - seen transversely to the direction of travel (15) - the pimples (26 ') of a strip of goods (27') are brought into alignment with the spaces (43, 48) of the pimples (26) of an adjacent strip of goods (27). 3. The method according to claim 1 or 2, characterized in that the pole knobs (26, 26 ') in both fields (11, 11') are formed with a local offset, but simultaneously and in time (21) with each other.

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