Method and apparatus for making a nonwoven from continuous filaments

Abstract

An apparatus for making nonwoven from continuous filaments has a spinner for spinning the filaments, a cooler for cooling the spun filaments, and a mesh belt that moves in a generally horizontal travel direction and that passes through a deposition location where the spun and cooled filaments are deposited on the mesh belt to form thereon a nonwoven web. A nose roller defines a deflection zone over which the mesh belt is deflected from its travel direction downstream of the deposition location. At least one lift roller above the mesh belt downstream of the deposition location separates the nonwoven web from the mesh belt at a separation location at a first spacing upstream from the deflection zone of the nose roller. A treatment device for the nonwoven web is provided downstream of the mesh belt in the travel direction and receiving the nonwoven web from the lift roller.

Claims

1. An apparatus for making nonwoven from continuous filaments, the apparatus comprising a spinner for spinning the filaments; a cooler for cooling the spun filaments; a mesh belt that moves in a generally horizontal travel direction and that passes through a deposition location where the spun and cooled filaments are deposited on the mesh belt to form thereon a nonwoven web; a nose roller defining a deflection zone over which the mesh belt is deflected from its travel direction; at least one lift roller above the mesh belt downstream of the deposition location and adjustable vertically relative to the mesh belt for separating the nonwoven web from the mesh belt at a separation location at a first spacing upstream from the deflection zone of the nose roller; and a treatment device for the nonwoven web downstream of the mesh belt in the travel direction and receiving the nonwoven web from the lift roller.

2. The apparatus according to claim 1, wherein the lift roller is set or positionable relative to the nose roller such that the separation location is spaced or orientable in the travel direction of the mesh belt upstream of the deflection zone, the lift roller being upstream or downstream of the nose roller in the travel direction of the mesh belt.

3. The apparatus according to claim 1, further comprising: a deflection roller supporting the mesh belt, offset by a second spacing upstream of the nose roller, and upstream of the deposition location, the first spacing being a maximum of 50% of the second spacing.

4. The apparatus according to claim 1, wherein the lift roller is rotatable and driven.

5. An apparatus for making nonwoven from continuous filaments, the apparatus comprising a spinner for spinning the filaments; a cooler for cooling the spun filaments; a mesh belt that moves in a generally horizontal travel direction and that passes through a deposition location where the spun and cooled filaments are deposited on the mesh belt to form thereon a nonwoven web; a nose roller defining a deflection zone over which the mesh belt is deflected from its travel direction; at least one lift roller above the mesh belt downstream of the deposition location and at or settable at a third spacing from the mesh belt, the and this third spacing is greater than 50% of a diameter of the lift roller for separating the nonwoven web from the mesh belt at a separation location at a first spacing upstream from the deflection zone of the nose roller; and a treatment device for the nonwoven web downstream of the mesh belt in the travel direction and receiving the nonwoven web from the lift roller.

6. The apparatus according to claim 5, wherein the diameter of the lift roller is 10 to 500 mm.

7. An apparatus for making nonwoven from continuous filaments, the apparatus comprising a spinner for spinning the filaments; a cooler for cooling the spun filaments; a mesh belt that moves in a generally horizontal travel direction and that passes through a deposition location where the spun and cooled filaments are deposited on the mesh belt to form thereon a nonwoven web; a nose roller defining a deflection zone over which the mesh belt is deflected from its travel direction; at least one first lift roller above the mesh belt downstream of the deposition location for separating the nonwoven web from the mesh belt at a separation location at a first spacing upstream from the deflection zone of the nose roller; a treatment device for the nonwoven web downstream of the mesh belt in the travel direction and receiving the nonwoven web from the lift roller; and a second lift roller in addition to the first lift roller and between the first lift roller and the deposition location.

8. The apparatus according to claim 7, wherein the first lift roller and the second lift roller have the same or substantially the same diameter and a fourth spacing between the axes of rotation of the two lift rollers is at least 105% of the lift-roll diameter.

9. The apparatus according to claim 7, wherein the nonwoven web passes under the second lift roller and over the first lift roller.

10. The apparatus according to claim 3, wherein the nose roller is movable or positionable vertically to angle the mesh belt at least between the deflection roller and the nose roller in the travel direction toward the device base at a downward slope from 3° to 20°.

11. The apparatus according to claim 10, wherein the nose roller is moved horizontally movable or extensible.

12. The apparatus according to claim 10, wherein the first spacing of the separation location from the nose roller is adjusted by the vertical movability and/or the horizontal movability or telescoping of the nose roller.

13. The apparatus according to claim 1, wherein the treatment device is a consolidator, a calender, or a winder.

14. The apparatus of claim 13, wherein the calender has a pair of calender rolls of which at least one is movable vertically.

15. The apparatus according to claim 1, wherein separation of the nonwoven web from the mesh belt takes place after preconsolidation of the nonwoven web.

16. An apparatus for making nonwoven from continuous filaments, the apparatus comprising a spinner for spinning the filaments; a cooler for cooling the spun filaments; a mesh belt that moves in a generally horizontal travel direction and that passes through a deposition location where the spun and cooled filaments are deposited on the mesh belt to form thereon a nonwoven web; a nose roller defining a deflection zone over which the mesh belt is deflected from its travel direction; at least one lift roller above the mesh belt downstream of the deposition location and a fifth spacing upstream from the nose roller that is at least 50% of the diameter of the lift roller for separating the nonwoven web from the mesh belt at a separation location at a first spacing upstream from the deflection zone of the nose roller; and a treatment device for the nonwoven web downstream of the mesh belt in the travel direction and receiving the nonwoven web from the lift roller.

17. A method of making nonwoven, the method comprising the steps of: spinning continuous filaments; cooling the spun filaments; moving a mesh belt in a generally horizontal travel direction through a deposition location and there depositing the cooled filaments on the mesh belt to form thereon a nonwoven web moving in the direction with the belt; deflecting the belt from its travel direction over a nose roller in a deflection zone downstream of the deposition location; passing the nonwoven web over a lift roller and thereby separating the nonwoven web from the mesh belt at a separation zone where the nonwoven web deviates from the travel direction; vertically adjusting a position of the lift roller relative to the mesh belt; orienting the lift roller to position the separation location at a spacing upstream from the nose roller; and, passing the nonwoven web from the lift roller to a downstream device.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

(2) FIG. 1 is a schematic vertical section through an apparatus according to the invention with two lift rollers in their starting positions,

(3) FIG. 2 shows the apparatus of FIG. 1 in a first operating or use position,

(4) FIG. 3 shows the apparatus according to FIG. 1 in a second operating or use position,

(5) FIG. 4 is an enlarged view of the nose roller and the lift rollers of the device in the use position of FIG. 2.

SPECIFIC DESCRIPTION OF THE INVENTION

(6) As seen in FIG. 1 an apparatus for making nonwoven from continuous filaments has a spinner formed by a spinneret 1 serving for spinning the filaments and a cooler 2 for cooling the filaments. Furthermore, a mesh belt 3 is provided on which the filaments can be deposited in a deposition location 4 of the nonwoven web 5. Appropriately and here according to the drawing, if the device is a spunbond device, it has a stretcher 17 for stretching the filaments. The continuous filaments can be monocomponent filaments made of at least one thermoplastic resin. The cooler 2 preferably and here has a cooling chamber 18 through which the continuous filaments pass. Preferably and here, upper and lower cooling compartments 19 and 20 flank the cooling chamber 18 on top of each other and feed air of different temperatures into the cooling chamber 18. Also preferably and here, between the spinner 1 and the cooler 2 there is a monomer aspirator or suction device 21 that withdraws noxious gases created by the spinning process from the apparatus. The noxious gases can for example be monomers or oligomers and the like.

(7) Appropriately and here the cooler 2 downstream in the filament-travel direction FS is the downstream stretcher 17 for stretching the filaments. According to the highly recommended embodiment and here the subassembly formed by the cooler 2 and the stretcher 17 is a closed subassembly, where apart from the supply of cooling air in the cooler 2 there is no further air supply into the closed subassembly.

(8) In the context of the invention and here between the stretcher 17 and the mesh belt 3 there is a diffuser 23 through which the continuous filaments pass. According to a recommended embodiment and here there is a secondary air inlet gap 24 for the introduction of secondary air into the diffuser 23 between the stretcher 17 and the diffuser 23. After passing through the diffuser 23, the continuous filaments are deposited on the mesh belt 3 in the area 4 of the nonwoven web 5 and then moved away by the mesh belt 3 in a travel direction T of the mesh belt 3. There is under the mesh belt 3 an aspirator 22 for extracting air or process air through the mesh belt 3.

(9) According to the invention, the mesh belt 3 passes at one deflection zone 6 around at least one nose roller 7 and is thereby deflected from its travel direction T. The nose roller 7 is spaced downstream of the deposition location 4 by a fourth spacing E. When the apparatus is running (FIGS. 2 to 4), the nonwoven web 5 is separated upstream of the deflection zone 6 from the mesh belt 3 and can then be transferred to at least one downstream treatment device 8. Here there are two downstream treatment devices 8: a calender 16 and a winder 26.

(10) In order to separate the nonwoven web 5 from the mesh belt 3, there are preferably and here according to the drawing two lift rollers 9 and 14. Recommended and here the lift rollers 9 and 14 can move vertically relative to the mesh belt 3. This can be seen in particular in FIG. 1. The lift rollers 9 and 14 are advantageously height adjustable or vertically displaceable between respective starting positions and respective lift positions. The starting positions of the lift rollers 9 and 14 as shown in FIG. 1 allow cleaning of the apparatus according to the invention and/or insertion of the nonwoven web when the apparatus is not running. Different lift positions of the rollers 9 and 14 are shown in FIG. 3 where the apparatus is running. In the use or lift position, the lift rollers 9 and 14 are above the mesh belt 3 and the nonwoven web 5 are separated by the lift rollers 9 and 14 from the mesh belt 3 at a separation location or line 10 that is set at a first spacing A upstream of the nose roller 7. The first spacing A between the nose roller 7 and the separation location or line 10 is in particular the spacing A between the axis of rotation of the nose roller 7 and the separation location or line 10. The first spacing A is between a projection of the axis of rotation of the nose roller 7 on the mesh belt 3 and the separation location or line 10, the projection of the axis of rotation being perpendicular to the longitudinal extension of the mesh belt 3 and falling in the area of the first spacing A (FIGS. 2 to 4).

(11) Recommended and here according to the drawing when the apparatus is running, the lift roller 9 is upstream in the travel direction T of the mesh belt 3 of the nose roller 7 (FIG. 2 or 3). The other lift roller 14 is preferably upstream in the travel direction T of the mesh belt 3 of the downstream roller 9.

(12) According to a particularly preferred embodiment of the invention the first spacing A is smaller than the second spacing C here between the downstream nose roller 7 and an upstream deflection roller 15. This upstream deflection roller 15 serves with the downstream nose roller 7 for movement of the mesh belt 3 in the travel direction T of the mesh belt 3 upstream of the nose roller 7. The deflection roller 15 is in this embodiment between the deposition location 4 and the deflection zone 6. The mesh belt 3 is either deflected at the roller 15 from its travel direction (FIG. 1) or passes in its travel direction straight past it (FIGS. 2 and 3) as explained in more detail below.

(13) The second spacing C between the nose roller 7 and the deflection roller 15 is in the context of the invention in particular the spacing between the axes of rotation of the nose roller 7 and the deflection roller 15, or between projections of the axes of rotation the mesh belt 3 perpendicular to the longitudinal extension of the mesh belt 3 in the area of the second spacing C. It is recommended that the first spacing A be a maximum of 30%, preferably a maximum of 20% of the second spacing C. Here according to FIG. 2, the spacing A may be about 5% of the second spacing C. Here according to FIG. 3, the first spacing A may be about 15% of the second spacing C.

(14) The lift rollers 9 and 14 here rotate about their axes. Diameters d.sub.1 and d.sub.2 of the lift rollers 9 and 14 are preferably 25 to 400 mm, especially preferably 100 to 250 mm. In the context of the invention and here the downstream lift roller 9 and the upstream lift roller 14 have the same or substantially the same diameter d.sub.1 or d.sub.2. Particularly preferred and in this embodiment (in particular FIG. 4) a spacing m between the axes of rotation of the two lift rollers 9 and 14 when the apparatus is running is at least 115% of the diameters d.sub.1 or d.sub.2 of the lift rollers 9 and 14. Here according to the drawing the spacing m between the axes of rotation of the two lift rollers 9 and 14 is about 130% of the diameter d.sub.1 or d.sub.2 of either of the lift rollers 9 and 14. In this context, the rotation-axis spacing m is in particular the spacing between the axes of rotation of the two lift rollers 9 and 14, where this rotation-axis spacing m is advantageously between projections perpendicular to the longitudinal extension of the mesh belt 3 or to the imaginary extension of this longitudinal extension of the axes of rotation of the lift rollers 9 and 14 on the mesh belt 3.

(15) Appropriately and here the lift rollers 9 and 14 are set relative to the mesh belt 3 at a mutual third spacing. This third spacing is in this context in particular the spacing between the axes of rotation of the respective lift rollers 9 and 14 parallel to the mesh belt 3. The third spacing to the mesh belt 3 is advantageously perpendicular to the longitudinal extension of the mesh belt 3 in the area of lift rollers 9 and 14 or to the imaginary extension of these longitudinal extension. In the example according to the drawing (in particular FIG. 3) the spacing of the first lift roller 9 from the mesh belt 3 is shown at D.sub.1 and the spacing of the second lift roller 14 from the mesh belt 3 at D.sub.2. In the context of the invention and here the third spacing or the spacings D.sub.1 and D.sub.2 are greater than 50% of either of the diameter d.sub.1 or d.sub.2 of the lift rollers 9 and 14.

(16) Also preferably and here, (in particular FIG. 3) the third spacing D.sub.1 of the first lift roller 9 from the mesh belt 3 is greater than the third spacing D.sub.2 of the second lift roller 14 from the mesh belt 3. The nonwoven web 5 runs advantageously and here, when the apparatus is running, under the second lift roller 14 and then over the first lift roller 9. This is shown in particular in FIGS. 2 to 4. The first lift roller 9 is preferably used for separating the nonwoven web 5 of the mesh belt 3. The second lift roller 14 serves for holding down the nonwoven web 5 on the mesh belt 3. The separation location 10 or line is thus advantageously and here near the second lift roller 14 and in particular below the second lift roller 14.

(17) According to the a preferred embodiment and here the nose roller 7 can be raised and lowered vertically to move the mesh belt 3 between the deflection roller 15 and the nose roller 7 in the travel direction T relative to a horizontal base 11 of the apparatus. Appropriately and here, the mesh belt in this area has a downward incline of 3° to 20°. Here according to FIG. 2 the downward incline is about 7° and according to FIG. 3 about 15°. the deflection roller 15 thus deflects the mesh belt 3 from its previous position with the travel direction T (FIGS. 2 and 3) running parallel to the device base 11. The movability of the nose roller 7 vertically in this connection is relative to the device base 11. Further preferably and here, the nose roller 7 is and can be moved or telescoped horizontally. “Horizontal” in this context is parallel to the device base 11. The horizontal movability or telescoping of the nose roller 7 entails movement this nose roller 7, for example, closer to the downstream treatment device 8 or the calender 16. Particularly preferably and here, the nose roller 7 is horizontally movable or telescopic and vertically movable, so that a wide variety of positions of the nose roller can be assumed. If according to a preferred embodiment and here the nose roller 7 can be moved or telescoped horizontally and can be shifted vertically, and in addition the lift rollers 9 and 14 can move vertically, different positions of the nose roller 7 can be set and the lift rollers 9 and 14 can be set in their lift positions such that in particular the first spacing A of the separation location 10 from the nose roller 7 when the apparatus is running can be set.

(18) Within the scope of the invention and here, the downstream treatment device 8 is a calender 16. The embodiment according to FIG. 1 has downstream in the travel direction therefrom the treatment device 8 in the form of a winder 26. Here according to the drawing, the calender 16 has three adjustable vertically calender rolls 12.1, 12.2 and 12.3. The nonwoven web 5 passes through a gap or nip between two of the calender rolls 12.1, 12.2, 12.3. The three calender rolls 12.1, 12.2, 12.3 are advantageously one above the other here. This creates two pairs of calender rolls, namely one between the top calender roll 12.1 and the middle calender roll 12.2 and another between the lowermost calender roll 12.3 and the middle calender roll 12.2. The nonwoven web 5 is consolidated or final consolidated here in consolidation zones 13 between the calender rolls 12.1, 12.2, 12.3. Such consolidation zones 13 of the calender 16 can consolidate or finally consolidate the nonwoven web 5. The consolidation zone 13 in this context is the area where at least one calender roll 12.1, 12.2, 12.3 can consolidated or finally consolidate the nonwoven web 5 by the action of the calender 16. As part of the invention and here according to FIGS. 2 to 4 the consolidation zone 13 of the calender 16 when the apparatus is running is above the nose roller 7 and arranged above the mesh belt 3.

(19) Further preferably and here, according to the drawing the separation of the nonwoven web 5 from the mesh belt 3 takes place after preconsolidation of the nonwoven web 5. The nonwoven web is thus as recommended and in the example preconsolidated upstream of the separation line 1 on the mesh belt 3 by a preconsolidator 25. This can be seen in particular in FIG. 1.

(20) It is also within the scope of the invention that the first lift roller 9 and/or the second lift roller 14 are offset from the nose roller 7 by respective spacing U.sub.1 and U.sub.2 that together are at least 50% of the diameter of the respective lift rollers 9 and 14. These spacings U.sub.1 and U.sub.2 in this context are in particular the spacings between the axes of rotation of the respective lift rollers 9 and 14 and the axis of rotation of the nose roller 7, the spacing U.sub.1 and U.sub.2 advantageously between the projections of the axes of rotation of the lift rollers 9 and 14 and the nose roller 7 parallel to the mesh belt 3, the projections of the axes of rotation perpendicular to the longitudinal extension of the mesh belt 3 or to the imaginary extension of this longitudinal extension is in the region of the spacings U.sub.1 and U.sub.2. In this embodiment according to the drawing the lift rollers 9 and 14 have respective center-to-center spacings U.sub.1 and U.sub.2 from the axis of the nose roller 7, which is at least 50% of the diameter d.sub.1 or d.sub.2 of the larger of the lift rollers 9 and 14 (FIG. 4).