Feed Device of a Machine for Forming a NonWoven Web

Abstract

The feed device for feeding individualized fibers or fiber flocks to a transport device which includes a first feed segment and a second feed segment for feeding in a starting material. Each feed segment has its own feed roller and each feed roller is individually actuatable. The feed device also includes an opening roller, which cooperates with the feed rollers of the first and second feed segments to individualize the starting material into fibers or fiber flocks. The first and second feed segments are arranged a certain distance apart in a circumferential direction of the opening roller.

Claims

1. A feed device for feeding individualized fibers or fiber flocks to a transport device, the feed device comprising: a plurality of feed segments for receiving and feeding a starting material, the plurality of feed segments at least comprising a first feed segment and a second feed segment, wherein the first feed segment has a first feed roller and the second feed segment has a second feed roller, and wherein the first and second feed rollers are individually actuatable; and an opening roller, which cooperates with the first and second feed rollers to individualize the starting material into fibers or fiber flocks; wherein the first and second feed segments are arranged a certain distance apart in a circumferential direction of the opening roller.

2. The feed device of claim 1 wherein the first and second feed segments are aligned with each other in the circumferential direction without any offset in an axial direction of the opening roller.

3. The feed device of claim 1 wherein the first and second feed segments are arranged with an offset from each other in an axial direction of the opening roller.

4. The feed device of claim 1 further comprising at least one third feed segment, which is aligned in an axial direction of the opening roller with the first feed segment.

5. The feed device of claim 4 further comprising at least one fourth feed segment, which is aligned in an axial direction of the opening roller with the second feed segment.

6. The feed device of claim 4 wherein the third feed segment comprises a third feed roller which is individually actuatable.

7. The feed device of claim 5 wherein the third and fourth feed segments comprise third and fourth feed rollers which are individually actuatable.

8. A nonwoven-forming machine for forming a material web, the nonwoven-forming machine comprising: a transport device conveyed in a transport direction; and a first feed device for scattering individualized fibers or fiber flocks onto the transport device, the first feed device comprising: a plurality of feed segments for taking in and feeding a starting material, the plurality of feed segments at least comprising a first feed segment and a second feed segment, wherein the first feed segment has a first feed roller and the second feed segment has a second feed roller; and an opening roller, which cooperates with the first and second feed rollers to individualize the starting material into fibers or fiber flocks; wherein the first and second feed segments are arranged a certain distance apart in a circumferential direction of the opening roller.

9. The nonwoven-forming machine of claim 8 further comprising a second feed device, the second feed device comprising: a plurality of feed segments for taking in and feeding a starting material, the plurality of feed segments at least comprising another first feed segment and another second feed segment, wherein the other first feed segment has another first feed roller and the other second feed segment has another second feed roller; and a second opening roller, which cooperates with the other first and second feed rollers to individualize the starting material into fibers or fiber flocks.

10. The nonwoven-forming machine of claim 9 wherein the first and second feed devices are arranged one behind the other in the transport direction, and wherein axes of the first and second opening rollers of the first and second feed devices are parallel to each other.

11. The nonwoven-forming machine of claim 9 wherein the first and second segments of the first feed device are offset in an axial direction of the first opening roller from the other first and second feed segments of the second feed device.

12. A method for forming a material web by a feed device having a plurality of feed segments, at least comprising a first and a second feed segment, and an opening roller, wherein the first and second feed segments are arranged a certain distance apart in a circumferential direction of the opening roller, the method comprising: providing a first starting material consisting of fibers at the first feed segment of the feed device; providing a second starting material consisting of fibers at the second feed segment, wherein at least one property of the fibers of the first starting material differs from a corresponding property of the fibers of the second starting material; feeding the first and second starting materials to the opening roller; individualizing the supplied starting material by the opening roller to form individualized fibers or fiber flocks of the supplied starting material; and scattering the individualized fibers or fiber flocks onto a transport device.

13. The method of claim 12 wherein the at least one property of the fibers of the first and second starting materials in which the fibers differ is selected from the group consisting of: a color of the fibers, a type of fiber, a fiber material, a fiber diameter, a fiber length, a treatment of the fibers, a cross-sectional shape of the fibers, a roughness or a crimping of the fibers.

14. The method of claim 12 wherein the first and second feed segments are aligned in a circumferential direction of the opening roller without any offset from each other in an axial direction of the opening roller, the method further comprising: feeding the first and second starting materials to the opening roller; varying the supplied quantity of the first or of the second starting material and thus setting a mixing ratio between the first and the second starting material, wherein the mixing ratio is between 0:1 and 1:0.

15. The method of claim 14 wherein the mixing ratio is between 0.01:1 and 1:0.01.

16. The method of claim 14 further comprising: forming a strip of fibers or fiber flocks on the transport device, in which the mixing ratio between the fibers or fiber flocks of the first starting material and the fibers or fiber flocks of the second starting material changes along the transport direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] FIG. 1 is a schematic side view of a nonwoven-forming machine;

[0033] FIG. 2 is a perspective view of one embodiment of a nonwoven-forming machine including a feed device according to the invention;

[0034] FIG. 3 is a perspective view of an alternative embodiment of a nonwoven-forming machine including a feed device according to the invention; and

[0035] FIG. 4 is a perspective view of another alternative embodiment of a nonwoven-forming machine including a feed device according to the invention.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

[0036] FIG. 1 shows a schematic side view of a nonwoven-forming machine 2. Nonwoven-forming machine 2 is set up to form a material web 4, in particular a card web or a fleece web. Nonwoven-forming machine 2 comprises a transport device 6 for conveying material web 4 in a transport direction T and at least one feed device 8 for delivering individualized fibers or fiber flocks to transport device 6. In the embodiment shown, feed device 8 forms a new material web 4. In an alternative embodiment, material web 4, e.g., any desired intermediate fleece product, can already be arranged on transport device 6 upstream of feed device 8 relative to transport direction T, and nonwoven-forming machine 2 distributes additional fibers or fiber flocks onto this material web to form a uniform material web 4 or a material web 4 with a surface profile.

[0037] Transport device 6 preferably moves continuously in transport direction T. Transport device 6 can be configured as an endless conveyor belt, preferably as a sieve belt with bottom suction. The speed of transport device 6 is preferably in the range of between 0.2 and 20 m/min, more preferably in the range of between 0.05 and 10 m/min.

[0038] Feed device 8 comprises a plurality of feed segments 10 (110, 210, 310 in FIGS. 2-4); to explain the general structure and general function of these segments, only one feed segment is shown in the side view of FIG. 1. One or more measuring devices (not shown), which measure the weight per unit area of material web 4 across the width extending transversely to the transport direction T, can be arranged upstream and/or downstream of feed device 8 in the manner familiar to the skilled person. On the basis of the data obtained from these measuring devices, the transverse profile can be determined, and on the basis of the movement of transport device 6 in transport direction T, the longitudinal profile of material web 4 can also be determined.

[0039] The formed material web 4 can be sent by transport device 6 to various alternative processing steps. In a first alternative, material web 4 is sent to card-forming device, preferably a carding machine, and is equalized there. In a second alternative, the material web is sent directly to a fleece former, e.g., an aerodynamic fleece former. In a third variant, the material web is individualized again before further processing. In a fourth alternative, the material web is sent directly to a solidification machine e.g., a needling machine.

[0040] A dispensing device 12 for the storage and controlled dispensing of a starting material 14, e.g., a fiber sliver or a fleece strip (as shown in FIGS. 2-4), is assigned to each feed segment 10 of feed device 8. In the exemplary embodiment shown, dispensing device 12 is configured as a spool, but it could also be provided in the form of a sliver can or the like. The starting material proceeds from dispensing device 12 to a preferably rubberized storage roller 16, which extends transversely to transport direction T and horizontally over preferably the entire width of feed device 8. A turn of a starting material 14 provided by dispensing device 12 is wrapped around storage roller 16. Storage roller 16 is driven, preferably by a servo motor 18 and also preferably continuously at a relatively slow speed. In certain embodiments, storage roller 16 could also be omitted.

[0041] Storage roller 16 can be configured as a one-piece unit. If several feed segments are arranged horizontally next to each other transversely to transport direction T (perpendicular to the plane of the drawing in FIG. 1), the storage roller can accept several strands of starting material 14 simultaneously for these feed segments 10. It is also possible, however, for there to be a separate storage roller 16 for each feed segment 10.

[0042] Feed segment 10 comprises a rotating feed roller 20, to which the starting material 14 is fed. In the embodiment shown, feed roller 20 pulls off starting material 14 provided by the associated dispensing device 12, either via the intermediate agency of storage roller 16 or directly. Feed rollers 20 of the plurality of feed segments 10 are preferably actuatable individually. For this purpose, each feed roller 20 is preferably driven by a servo motor 22. Each feed roller 20 also comprises a set of projecting teeth (not shown) for drawing in the starting material 14.

[0043] Starting material 14 carried along by the feed rollers 20 is preferably sent via a trough 24 to an opening roller 26. Opening roller 26 can be configured as a one-piece unit and extend transversely to transport direction T over the entire width of feed device 8, preferably over the entire width of material web 4 to be formed. Opening roller 26, however, could also comprise individual segments, which are oriented axially with respect to each other transversely to transport direction T.

[0044] Opening roller 26 can be driven in the same rotational direction as feed roller 20. Opening roller 26 also comprises a set of projecting teeth. For example, each feed roller 20 comprises a set of teeth which project backwards with respect to the rotational direction of the associated feed roller 20, and opening roller 26 comprises a set of teeth projecting forwards with respect to the rotational direction of opening roller 26. The sets of teeth of feed rollers 20 and of opening roller 26, however, can also be configured in some other conventional manner.

[0045] Opening roller 26 cooperates with feed rollers 20 to individualize starting material 14. In particular, opening roller 26 and feed rollers 20 are especially effective at opening up the twisted or compacted starting material 14 of a fiber sliver or a fiber fleece strip, so that loose flocks or even fine fibers are separated. These drop into an appropriate discharge shaft 28 and fall from there onto transport device 6. In addition, an optional cleaning roller 30 can be provided, which strips off the fibers or fiber flocks adhering to opening roller 26 from the roller, so that these, too, can drop into discharge shaft 28.

[0046] FIG. 2 shows a schematic view, in perspective, of a first embodiment of a nonwoven-forming machine 2 comprising a feed device 8 according to the invention. As previously described, feed device 8 serves to feed individualized fibers or fiber flocks to transport device 6 and comprises an opening roller 26 as well as a plurality of feed segments 110, 210, 310, which can have a configuration similar to that of feed segment 10 described on the basis of FIG. 1. In particular, feed device 8 comprises at least one first feed segment 110 and one second feed segment 210. The first and second feed segments 110, 210 are a certain distance apart in the circumferential direction U of opening roller 26. In the embodiment shown, an optional third feed segment 310 is also arranged a certain distance away from the first and second feed segments 110, 210 in the circumferential direction U of opening roller 26.

[0047] Each feed segment 110, 210, 310 is fed with a strand of twisted or compacted starting material 114, 214, 314. Alternatively, each feed segment 110, 210, 310 can also be fed with a plurality of strands of the starting material 114, 214, 314, e.g., with two or three strands.

[0048] The first feed segment 110 comprises a feed roller 120; the second feed segment 210 comprises a feed roller 220; and the third feed segment 310 comprises a third feed roller 320. Opening roller 26 cooperates with the feed rollers 120, 220, 320 to individualize the associated starting material 114, 214, 314. For this purpose, the feed segments 110, 210, 310 are arranged on the circumference of the opening roller.

[0049] Because, as shown here, the first and second feed segments 110, 210 and the optional third feed segment 310 are spaced in the circumferential direction U of the opening roller 26, new possibilities for arranging the plurality of feed segments of a feed device 8 and new possible applications for nonwoven-forming machine 2 as such are obtained.

[0050] In the embodiment according to FIG. 2, first and second feed segments 110, 210 and the third feed segment 310 are aligned with respect to each other without any offset in the axial direction A of the opening roller 26. Axial direction A of opening roller 26 is parallel to the rotational axis of opening roller 26 and thus, in the preferred embodiment, is transverse to the transport direction T. Because the first, second and third feed segments 110, 210, 310 are aligned with each other in axial direction A, they form a row of feed segments 110, 210, 310, arranged one behind another in the circumferential direction U. The fibers or fiber flocks provided by the first, second, and third feed segments 110, 210, 310 arranged to form a row of feed segments 110, 210, 310, cooperate with opening roller 26 to form a strip of flocks or fibers on transport device 6.

[0051] Feed segments 110, 210, 310 of such a row can be supplied with starting materials 114, 214, 314 which differ from each other with respect to at least one property. As a result, the properties of the material web 4 can in turn be effectively adjusted in the longitudinal direction of the material web. For example, a first starting material 114 is supplied to the first feed segment 110; a second starting material 214 is supplied to the second feed segment 210; and a third starting material 314 is supplied to the optional third feed segment 310. At least one of the properties of the fibers of first, second and third starting materials 114, 214, 314 can differ from the corresponding property of the fibers of the other starting materials 114, 214, 314. The at least one property of the fibers of first, second, and third starting materials 114, 214, 314 by which the fibers differ is preferably selected from the color of the fibers, the type of fiber, the fiber material, the fiber size, or the fiber treatment, as previously described.

[0052] Once first, second, and third starting materials 114, 214, 314 have been supplied to feed segments 110, 210, 310 arranged in a row one behind the other in the circumferential direction U of opening roller 26, it is possible to vary the supplied quantity of the first and/or second and/or third starting material 114, 214, 314 independently of each other. This can be achieved in particular in that feed rollers 120, 220, 320 of the first, second, and third feed segments can be actuated individually. As a result, each feed roller 120, 220, 320 can be driven or not driven, as a result of which the feed of associated starting material 114, 214, 314 can be turned on or off. In addition, the rotational speed of individual feed rollers 120, 220, 320 can be regulated, as a result of which the quantity of the associated starting material 114, 214, 314 which has been supplied can be regulated.

[0053] The end result is that any desired mixing ratio between the first, second, and third starting materials 114, 214, 314 can be set. In particular, the mixing ratio can also be adjusted during operation.

[0054] One of starting materials 114, 214, 314 or any desired mixtures of one of starting materials 114, 214, 314 with one or both of the other starting materials, furthermore, can be delivered to transport device 6 so that they alternate in the transport direction T. As a result, it is possible, for example, to produce colored patterns in material web 4. It is also possible, however, to influence the mechanical properties of the material web in that, for example, fibers of different types, of different materials, or of different sizes can be delivered.

[0055] It is also preferred that feed device 8 comprise at least one additional feed segment which is aligned in axial direction A with the first or second feed segment 110, 210. As a result, a row of feed segments arranged next to each other in the axial direction A is obtained. The additional feed segments are characterized in FIGS. 2-4 by the addition of a or b. The additional feed segments are optional, and an additional feed segment or a plurality of additional feed segments can be assigned to each of the first, second and third feed segments 110, 210, 310. The additional feed segments are preferably configured in a manner similar to that of the previously described feed segments 10, 110, 210, 310, unless otherwise described.

[0056] In the embodiment illustrated here, feed device 8 comprises the additional feed segments 110a and 110b, which are aligned axially with first feed segment 110; additional feed segments 210a and 210b, which are aligned axially with second feed segment 210; and additional feed segments 310a and 310b, which are axially aligned with third feed segment 310. It is preferred that each of the additional feed segments 110a, 110b, 210a, 210b, 310a, 310b be individually actuatable. For this purpose, each feed segment 110, 110a, 110b, 210, 210a, 210b, 310, 310a, 310b of the feed device preferably comprises its own feed roller 120, 220, 320, as a result of which the feed of the starting material 114, 214, 314 to each feed segment can be individually regulated.

[0057] According to FIG. 2, additional feed segments 110a, 210a, 310a are also aligned with each other in the circumferential direction U of the opening roller 26 without any offset in the axial direction A; and additional feed segments 110b, 210b, 310b are correspondingly aligned with respect to each other in the circumferential direction U so that in each case an additional row of feed segments 110a, 210a, 310a and 110b, 210b, 310b arranged one behind the other is formed.

[0058] Feed device 8 therefore comprises, in all, nine feed segments 110, 110a, 110b; 210, 210a, 210b; 310, 310a, 310b, which are arranged in three rows, one behind the other, in the circumferential direction U and in three rows adjacent to each other in the axial direction A.

[0059] Feed segments 110, 110a, 110b; 210, 210a, 210b; 310, 310a, 310b arranged adjacent to each other in the axial direction A can be operated synchronously, so that a newly formed material web 4 has a substantially homogeneous configuration transversely to transport direction T. These feed segments, however, can also be operated independently of each other to produce a surface profile transverse to the transport direction T of material web 4, or to compensate for an undesirable surface profile in a material web already present on transport device 6.

[0060] Feed segments 110, 110a, 110b; 210, 210a, 210b; 310, 310a, 310b arranged adjacent to each other in the axial direction A can each be fed with a starting material 114, 214, 314 which corresponds to the starting material 114, 214, 314 of the other feed segments of the axial row. It is also possible, however, that each of these feed segments could be fed with a starting material 114, 214, 314 whose fibers differ in at least one property from the corresponding property of the fibers of the other starting materials 114, 214, 214, as previously described.

[0061] The three rows of feed segments arranged in a row one behind the other in the circumferential direction U are spaced a certain distance apart in the axial direction A. A minimum distance between feed segments axially adjacent to each other is determined by the amount of space required to accommodate the bearings of the axial ends of the associated feed rollers in feed device 8. This has led to the situation that the fiber distribution transverse to the transport direction T on transport device 6 is nonuniform even when the feed segments adjacent to each other in the axial direction A are operated synchronously. This effect is amplified even more by the fact that the starting material is usually supplied centrally to the associated feed segment, and the fiber distribution therefore decreases across the width of a feed segment toward the edges of that feed segment.

[0062] FIG. 3 therefore shows an embodiment of the feed device 8 or of the nonwoven-forming machine 2 in which the feed segments are arranged to counteract this effect. What was said above applies analogously here to the nonwoven-forming machine 2, to the feed device 8, and to its feed segments 110, 110a, 210, 210a, 210b with the difference that the feed segments have a different arrangement relative to each other.

[0063] As previously described, the first and second feed segments 110, 210 are arranged again a certain distance apart from each other in the circumferential direction U of the opening roller 26. Optionally, another feed segment 110a is aligned with the first feed segment 110, and two additional feed segments 210a and 210b are aligned with the second feed segment 210. More additional feed segments or fewer additional feed segments can be provided, and, in analogy to FIG. 2, a third feed segment 310 with or without additional feed segments assigned to it can also be present.

[0064] The first and second feed segments 110, 210 according to FIG. 3, however, are arranged with an offset from each other in the axial direction A of the opening roller 26. The first and second feed segments 110, 210 therefore do not form a row of feed segments arranged one behind the other in the circumferential direction U without an offset in the axial direction A. The additional feed segments 110a, 210a, 210b do not form any such rows either.

[0065] It is preferred that the working areas of the first and second feed segments 110, 210 overlap in the circumferential direction U. That is, a portion of the area of the lateral surface of the opening roller 26 which cooperates with the feed roller 120 of the first feed segment 110 simultaneously cooperates with the feed roller 220 of the second feed segment 210. The overlapping of the working areas of the first and second feed segments 110, 210 have the effect that fibers or fiber flocks of both the first and second feed segments 110, 210 are distributed onto the transport device 6 in the area of this overlap. The smaller quantity of fibers present in the edge area of each individual feed segment 110, 210 can thus be compensated.

[0066] In the embodiment according to FIG. 3, the feed segments 110, 110a, 210, 210a, 210b are arranged in two rows of axially adjacent feed segments 110, 110a and 210, 210a, 210b. The feed segments 110, 110a of the one row are offset in the axial direction from the feed segments 210, 210a, 210b of the other row. It is preferred that, as a result of this arrangement, there be no areas in the axial direction of opening roller 26 in which the opening roller does not cooperate with at least one feed roller of the feed segments. More precisely, first feed segment 110 is arranged axially in such a way that its working area overlaps the working areas of second feed segment 210 and of additional feed segment 210a. In spite of the axial spacing between second feed segment 210 and additional feed segment 210a, there is therefore no area on the transport device corresponding to this axial spacing onto which no fibers or fiber flocks are distributed. Correspondingly, additional feed segment 110a is arranged in the axial direction in such a way that its working area overlaps the working areas of additional feed segment 210a and of additional feed segment 210b. This arrangement can be scaled in any way desired both in circumferential direction U and in axial direction A.

[0067] In this embodiment, however, it is possible to only a limited extent to set a mixing ratio between fibers of different properties or to feed fibers or fiber flocks of different properties in the transport direction T of material web 4, as described with reference to FIG. 2.

[0068] FIG. 4 therefore shows an embodiment of a nonwoven-forming machine 2 which combines the advantages of the previously described embodiments according to FIGS. 2 and 3. Nonwoven-forming machine 2 according to FIG. 4 comprises a first feed device 40 and a second feed device 42 for delivering individualized fibers or fiber flocks to transport device 6. The two feed devices 8, 40 are arranged one behind the other in transport direction T, so that the axes of opening rollers 26 of the two feed devices 8, 40 are parallel to each other.

[0069] First feed device 40 corresponds to feed device 8 according to FIG. 2. The corresponding explanations apply here as well.

[0070] Second feed device 42 corresponds substantially to feed device 8 according to FIG. 2, wherein it comprises only two rows of feed segments 110, 210, 310 and 110a, 210a, 310a, arranged one behind the other in the circumferential direction U. More precisely, the first, the second, and the third feed segment 110, 210, 310 of second feed device 42 form a first row of feed segments arranged one behind the other, and the additional feed segments 110a, 210a, 310a of second feed device 42 form a second row of feed segments arranged on behind the other, wherein the first and the second rows extend in circumferential direction U of opening roller 26.

[0071] As described above, feed device 40 comprises three rows of feed segments arranged on behind the other in circumferential direction U of opening roller 26, namely, one row of feed segments 110, 210, 310; another row consisting of the feed segments 110a, 210a, 310a; and an additional row consisting of the feed segments 110b, 210b, 310b.

[0072] Both in the case of first feed device 40 and in the case of second feed device 42, each row of feed segments arranged one behind the other in the circumferential direction U makes it possible to supply different starting materials within one row, as a result of which it is possible to dispense different fibers or fiber flocks in any desired mixing ratio.

[0073] In order, furthermore, to counteract the disadvantages of intermediate spaces in the axial direction between the rows of feed segments arranged on behind the other, that is, between two feed segments arranged next to each other in the axial direction, the rows of feed segments of first feed device 40 arranged one behind the other are offset in the axial direction A of opening roller 26 from the rows of feed segments of second feed device 42 arranged one behind the other.

[0074] In this way, fibers or fiber flocks are supplied by first feed device 40 to areas of transport device 6 onto which second feed device 42 is, as a result of its structural design, unable to supply any fibers or fiber flocks or is able to supply only a few of them. As a result, it is possible to achieve an equalization or to create a profile over the entire width of a material web 4 transversely to transport direction T, whereas the ability to supply a variety of different starting materials and to deliver them in any desired mixing ratios can be exploited at the same time.

[0075] It is obvious that the skilled person, within the scope of the claimed teaching, can adapt the number of feed segments of a feed device both in the circumferential direction and in the axial direction, as well as the number of feed devices in a nonwoven-forming machine in any way desired to satisfy the given requirements and desires. As many feed segments as desired can be arranged next to each other in a row in the axial direction, and as many feed segments as desired can be arranged around the opening roller in the circumferential direction of the roller.