EP0040482B1 - Process and apparatus for melt spinning filaments in which quench gas and finishing liquid are introduced to the filaments through the fibre pack and spinneret - Google Patents
Process and apparatus for melt spinning filaments in which quench gas and finishing liquid are introduced to the filaments through the fibre pack and spinneret Download PDFInfo
- Publication number
- EP0040482B1 EP0040482B1 EP19810301913 EP81301913A EP0040482B1 EP 0040482 B1 EP0040482 B1 EP 0040482B1 EP 19810301913 EP19810301913 EP 19810301913 EP 81301913 A EP81301913 A EP 81301913A EP 0040482 B1 EP0040482 B1 EP 0040482B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- filaments
- spinneret
- pack
- gas
- finish
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
- D01D5/00—Formation of filaments, threads, or the like
- D01D5/08—Melt spinning methods
- D01D5/088—Cooling filaments, threads or the like, leaving the spinnerettes
- D01D5/092—Cooling filaments, threads or the like, leaving the spinnerettes in shafts or chimneys
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Textile Engineering (AREA)
- Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
Description
- The present invention relates to the manufacture of melt spun polymeric filaments and, in particular, to the quenching and application of a finishing liquid to the spun filaments as they emerge from the spinneret.
- The manufacture of melt spun polymeric filaments is typically achieved by extruding a molten polymer, such as polyester or polyamide through a spinneret and then cooling the filaments thus formed. Therebelow, the filaments are converged and gathered at a guide and delivered to a bobbin or further treatment station. A finishing liquid is applied to the filaments below the quench zone. The finishing liquid may comprise a substance suitable for imparting a desired property to the filaments, such as smoothness, drape, lustre, water repel- lancy, flame retardancy, or crease resistance, for example.
- The manner in which the filaments are cooled has a significant impact on the resulting quality of the filaments. A typical cooling technique involves a gas quench in which cool air is blown across the filaments as they emerge from the spinneret. In instances where the filaments are extruded in the form of a circular array, it is common to utilize an outflow quench technique in which the filaments are passed downwardly in surrounding relation to an upwardly extending air pipe, the latter being arranged generally coincident with the central axis of the group of filaments. Quench air is directed radially or laterally outwardly through the filament group from an upper, apertured end of the pipe, the air preferably dispersed by a porous sheathing surrounding the apertures. There is thus produced a controlled cooling of the filaments. For example, see US Patents 3 135 811; 3 259 681; 3858386 and 3 969 462.
- In Japanese Patent Publication 52-27815 (Teijin) there is disclosed an 'opposed' quench system in which some of the quench gas is directed from outside an annular group of filaments and some quench gas is directed from inside the group of filaments, such inside gas quench having been introduced through the melt spinning pack. With such a system, the outer filaments and the inner filaments are blown into contact with each other and there is the likelihood that they will adhere together. Furthermore in the described system the inside gas quench travels parallel to the filaments. thereby impeding heat transfer.
- In Figures 1 A, 1 B there is depicted a conventional melt-spinning
apparatus 10 wherein aconventional filter pack 12 carries aconventional spinneret 14 through which a molten polymer, such as polyester or polyamide is downwardly extruded to form filaments. The spinneret is of a conventional type comprising holes arranged in an annular pattern so that agroup 15 of circularly arrangedfilaments 16 is formed. The holes of the spinneret are preferably arranged in a series of circular rows having a common central axis. The spun filaments are split into two groups and travel downwardly to two turning guides 9, or godets or rolls, at which they are gathered and redirected, in conventional fashion. - The
pack 12 is mounted on aconventional superstructure 20, and the filaments travel downwardly within acabinet 22 closed at least on three sides and possibly open at the fourth side for operator monitoring purposes. - Quench gas in the form of air is provided to cool the
filaments 16 emerging from the spinneret. The quench gas is delivered through an upwardly extending quench gas conduit 1 which includes a gas supply portion 2 and a gas discharge portion 3, which comprises a perforated hole pattern to obtain a required profile. The gas supply portion extends horizontally into the group of filaments and forms an elbow 4. Openings are provided in the gas discharge portion to discharge quench air radially outwardly, with the desired profile, through the surrounding filaments. Aporous sheath 5 surrounds the gas discharge portion to uniformly disperse the discharging air. - The upper end of the conduit 1 includes a
pin 6 which is received in an opening of thespinneret 14 to prevent lateral displacement of the conduit 1. - As is apparent from Figure 1 B, the
filaments 16 are separated into two bunches 7, 8 to avoid contacting the elbow portion of the conduit 1. The separate filaments bunches are gathered and redirected at a pair of turning guides 9. - In operation, quench air is delivered via the conduit 1 and is discharged radially outwardly from within the group of filaments emerging from the spinneret. The quenched filaments are separated into bunches 7, 8 and are gathered and redirected at the guides 9 for collection, or further treatment.
- It will be appreciated that the conduit 1 is often of substantial height, thereby increasing the overall height of the machine and rendering it difficult to maintain the conduit in alignment with the longitudinal axis defined by the filament group. This arrangement renders it difficult to maintain constant the distance from the spinneret to the uppermost quench air stream.
Air gaps 16A are formed between the filament bunches 7, 8 which gaps promote undesirable air turbulence. To limit the ability of the filaments to contact the elbow, the diameter of the conduit 1 is minimized, but this restricts the quantity of air flow that can be conducted and also increases the pressure drop. - As previously indicated, the lower portion of the air pipe forms an elbow and passes horizontally through the group of filaments above the turning guide. In order to prevent the downwardly converging group of filaments from rubbing against the elbow, the pipe diameter is minimized and the filament group is divided into two bundles, each bundle fed to a separate turning guide, as depicted herein in Figure 1 B for example.
- The minimization of the air pipe diameter at low pressures below 0.3515 Kg/cm2 results in the quantity of air flow being less than that normally desired for optimum cooling performance. In addition, enlarged air gaps are formed between the separate bundles, which gaps promote air turbulence, non-uniform quenching of the filaments and increased drag action on the filaments. Also, the extra handling of the filaments increases the overall wear and tear to which they are subjected.
- As regards the air pipe itself, the elbow must be placed at a level sufficiently below the quench zone to allow the filaments to be effectively divided into separate bundles. This results in a relatively long air pipe height which increases the overall machine height and renders it difficult to maintain the pipe aligned with the central axis of the filament group to assure that uniform quenching action is achieved.
- It will be understood that the vertical distance between the extrusion holes of the spinneret and the uppermost stream of cooling air is of critical importance regarding the quality of filaments being produced. It is thus required that a predetermined distance be maintained at all times, a feat not easily accomplished with an air pipe of relatively great height which is anchored somewhere at its lower end remote from the spinneret.
- It will also be appreciated that the splitting of the filament group into bundles considerably limits the available free area around the filament travel path and thus restricts the operator's access.
- The application of finishing liquid has heretofore been accomplished, for example, by means of a stationary applicator within which the filaments are gathered. Finishing fluid is caused to flow across the applicator surface and onto the gathered filaments. Another technique involves spraying the finishing liquid onto the filaments which have been gathered at the turning guide. It will be appreciated that the quality of the filaments produced is affected by the uniformity of application of the finishing liquid. The application of the liquid to the filaments when the latter are in a gathered or bunched-up condition is difficult to achieve with the desired uniformity.
- According to the present invention we provide a melt-spinning process in which molten polymer is extruded downwardly through a fibre pack and through an annular array of holes in a spinneret to form a circularly arranged group of filaments, quench gas is delivered downwardly through the pack and across the filaments emerging from the spinneret, a finish substance is applied to the filaments, and the filaments are gathered and redirected at a stationary or rotating guide, characterised in that all of the quench gas is delivered downwardly through the pack and spinneret coaxially relative to the array of holes and such finish substance having been conducted through the pack and through the spinneret at least partly internally of the flow of quench gas and being discharged outwardly from within the groups of filaments at a level below the discharge of quench gas and above the guide.
- In a preferred process, the finish substance is conducted wholly internally of the quench gas delivered through the pack and spinneret.
- We also provide an apparatus for the manufacture of melt-spun filaments in which molten polymer is extruded downwardly through a fibre pack and through an annular array of holes in a spinneret to form circularly arranged group of filaments, the apparatus including quenching means for directing quenching gas across the filaments emerging from the spinneret, means for applying a finishing substance on to the filaments and a stationary or rotating guide therebelow at which the filaments are gathered and redirected, characterised in that the quenching means comprises a gas supply conduit extending downwardly through the pack and the spinneret, the conduit including gas discharge means and the means for applying a finishing substance comprises a finish supply conduit extending downwardly through the pack and the spinneret within the gas supply conduit the finish supply conduit projecting below the gas discharge means coaxially within the groups of filaments and including a means for discharging finish on to the filaments.
- The advantages of the invention will become apparent from the following detailed description of preferred embodiments thereof in connection with the accompanying drawings in which like numerals designate like elements, and in which.
- Figure 1A is a front view in vertical section of a melt-spinning apparatus according to the prior art;
- Figure 1B is a view similar to Figure 1A but observed from the side to illustrate the separation of filments into bunches; and
- Figure 2 is a vertical sectional view through a melt-spinning apparatus according to the present invention.
- Figure 3 is a vertical sectional view through a modified melt-spinning apparatus according to the present invention including means for applying a finish substance on to the filaments.
- An apparatus according to this invention is depicted in Figure 2. Quench gas is delivered by a quenching
conduit 24 which includes agas supply portion 26 and agas discharge portion 28. Thegas supply portion 26 extends downwardly through thepack 12 and spinneret 14 in coaxial relationship with the axis defined by the circular arrays of spinneret holes. Thus, in contrast to the prior art, the presence of an elbow below the quench is eliminated. - The
gas discharge portion 28 is disposed immediately below the spinneret 14 and includes a plurality of outlet openings for discharging the quench air laterally outwardly with the desired profile, through the surroundingfilaments 16. It will, of course, be appreciated that the hole arrangement for a given profile with this invention is necessarily different from the hole arrangement of the prior art. Preferably, a sheath ofporous foam 30 surrounds the conduit discharge portion to uniformly disperse the quench air. Acollar 31 may be located on theconduit 24 to position the sheath. - It will be appreciated that quench air passes through the filaments, bellowing them radially outwardly.
- The section of the
gas supply portion 26 extending through thepack 12 is preferably surrounded by an air gap 35 to minimize heat exchange between the quench gas and molten polymer within thepack 12. Alternatively, or in addition, that section of thegas supply portion 26 could be covered with thermal insulation. - The
gas supply conduit 24 includes a fixedstop collar 34 which rests upon astop shoulder 36 on the pack to support thesupply conduit 24 and fixedly locate the latter relative to the spinneret. In this fashion, the spacial relationship between the spinneret holes and the uppermost stream of quench gas is maintained constant, to achieve uniformity of the quenching action and reduce birefringence variance in the filaments produced. These improvements occur within and between melt-spinning positions. - Extending downwardly from the lower end of the
discharge portion 28 of the conduit is agas streamlining member 38 in the form of a downwardly converging cone. The cone occupies a considerable portion of the space bounded by the convergingfilaments 16. Air normally drawn downwardly by the rapidly travelling filaments is constrained by the cone to flow in a smoother non-turbulent fashion to minimize undesired vibration of the filaments. Thecone 38 can be secured to the lower end of theconduit 28 in any suitable manner, preferably in a releasable manner, such as by screws, bayonet coupling, etc. - It is preferable that the diameter defined by the innermost circular row of holes in the spinneret be at least 12.7 cm to allow sufficient room for the
gas supply conduit 26 to pass therethrough. Smaller diameters could be employed, but the gas conduit would then probably be smaller then needed to conduct an optimum gas flow quantity. - If desired, a finishing liquid may be applied in a conventional manner to the filaments in the vicinity of a conventional stationary or
rotating guide 46 at which the filaments are gathered and redirected. - The apparatus depicted in Figure 3 is similar to that depicted in Figure 2 apart from certain modifications which are now described.
- Extending downwardly through the quench
conduit 24 and through theair streamlining cone 38 is afinish supply conduit 40 which conducts a suitable finishing liquid. The lower end ofconduit 40 projects beyond the bottom of thecone 38 and carries aspray nozzle 42. Thespray nozzle 42 is fixed by acollar 44 and is oriented to spray the finish liquid, in mist form, in a downward and laterally outward direction, so that the liquid passes outwardly through the group offilaments 16 after the latter have been quenched. - It will be understood that the location of the spray nozzle relatively close to the quench zone and high above the
usual guide 46, or godet or roll, advantageously affects the uniformity of the finish application. At such location the filaments are not gathered too closely together to inhibit a uniform travel of the finish substance, and are spaced sufficiently near the central axis of the group to receive a concentrated quantity of the sprayed finish. - The presence of the streamlining
cone 38 aids in smoothing-out the flow of air in the vicinity of the nozzle, thereby minimizing undesired turbulent swirling actions which could adversely affect the spraying action. - As a result, the filaments receive a substantially uniform application of the finish substance.
- Spraying of the finishing substance through the filaments while they are in a separated condition aids not only in achieving a uniform application of finish but also in augmenting the filament cooling step because the finish substance is typically of a lower temperature than are the filaments at the disclosed region of finish application.
- By locating the finish supply conduit within the quench
gas conduit 24, the finish application can be achieved without reducing access space within thecabinet 22 and without inhibiting the travel of the filaments. - In operation, the
filaments 16 are formed in circular arrays in conventional fashion. Quench air is conducted downwardly through thepack 12 via theconduit 24 and discharged radially outwardly through the group of filaments to cool the latter. Air currents immediately below theconduit 24 are guided in streamlined fashion by the streamliningcone 38 toward thefinish spray nozzle 42. Finish substance is sprayed outwardly from the nozzle and uniformly covers the cooled, still separatedfilaments 16. The smooth air flow established by the cone achieves a low turbulence spray - pattern to the filaments. Application of the finish spray also aids in further cooling down the filaments. Thereafter, the filaments are gathered and redirected at theguide 46. - It will be appreciated that the application of finish spray from within the filament group and at a level above the midpoint of the distance between the spinneret and the turning guide promotes a uniformity of the application because of the proximity of the filaments to the longitudinal axis and the still-separated condition of the filaments relative to one another. The air streamlining cone minimizes turbulence in the spray pattern to aid in achieving such uniformity. There is also achieved a final cooling of the filaments.
- By conducting the finish substance through the quench gas conduit, operator accessibility within the cabinet is not affected and no hindrance to filament travel is produced.
- It will be appreciated that the present invention eliminates the need for an elbow in the quench gas supply conduit below the quench zone, and thereby eliminates the need for dividing the filaments into separate bundles. As a result, it is generally unnecessary to restrict the size of the gas supply conduit and thus an optimum amount of quench gas flow can be provided. Since it is unnecessary to provide a quenching gas conduit of substantial height below the spinneret, the overall machine height is reduced, and it is also easier to align the quench conduit with the axis of the filament group.
- Because the quench gas conduit is mounted on the pack, a constant uniform distance between the spinneret holes and the uppermost quench air stream may easily be maintained, thereby assuring uniform quality and minimal birefringence variability of filaments produced.
- The-filaments are not subjected to extra wear and tear by rubbing against unlubricated surfaces such as quench elbows. Also, since the filaments need no longer be separated into bundles, air gaps previously formed between the bundles, and which promoted air turbulence around the filaments, no longer exist. Turbulence is further reduced by the presence of the streamlining cone which extends below the outlet of the quench gas duct.
Claims (8)
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US149370 | 1980-05-13 | ||
US06/149,370 US4285646A (en) | 1980-05-13 | 1980-05-13 | Apparatus for quenching melt-spun filaments |
US164425 | 1980-06-30 | ||
US06/164,425 US4288207A (en) | 1980-06-30 | 1980-06-30 | Apparatus for producing melt-spun filaments |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0040482A1 EP0040482A1 (en) | 1981-11-25 |
EP0040482B1 true EP0040482B1 (en) | 1984-08-08 |
Family
ID=26846674
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19810301913 Expired EP0040482B1 (en) | 1980-05-13 | 1981-04-30 | Process and apparatus for melt spinning filaments in which quench gas and finishing liquid are introduced to the filaments through the fibre pack and spinneret |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP0040482B1 (en) |
BR (1) | BR8102826A (en) |
CA (1) | CA1162710A (en) |
DE (1) | DE3165354D1 (en) |
MX (1) | MX154777A (en) |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CH673659A5 (en) * | 1987-03-05 | 1990-03-30 | Inventa Ag | |
CH667676A5 (en) * | 1985-09-18 | 1988-10-31 | Inventa Ag | DEVICE FOR COOLING AND PREPARING MELT-SPONNED SPINNING MATERIAL. |
FR2611748B2 (en) * | 1985-09-18 | 1990-07-27 | Inventa Ag | DEVICE FOR COOLING AND PREPARING MOLTEN YARNS |
DE3822571A1 (en) * | 1988-07-04 | 1990-02-01 | Hoechst Ag | SPINNING METHOD AND DEVICE FOR IMPLEMENTING THEREOF |
ATA53792A (en) * | 1992-03-17 | 1995-02-15 | Chemiefaser Lenzing Ag | METHOD FOR PRODUCING CELLULOSIC MOLDED BODIES, DEVICE FOR IMPLEMENTING THE METHOD AND USE OF A SPINNING DEVICE |
TR28441A (en) * | 1993-05-24 | 1996-07-04 | Courtaulds Fibres Holdings Ltd | Spinning cells that can be used to coagulate lyocell filaments. |
AT399729B (en) * | 1993-07-01 | 1995-07-25 | Chemiefaser Lenzing Ag | METHOD FOR PRODUCING CELLULOSIC FIBERS AND DEVICE FOR IMPLEMENTING THE METHOD AND THE USE THEREOF |
AT402738B (en) * | 1993-07-28 | 1997-08-25 | Chemiefaser Lenzing Ag | SPIDER NOZZLE |
CN114875503A (en) * | 2022-06-18 | 2022-08-09 | 盐城市力马空调工程有限公司 | Airless spinning cooling forming process, device and spinning equipment |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
BE631629A (en) * | 1962-04-27 | |||
US3969462A (en) * | 1971-07-06 | 1976-07-13 | Fiber Industries, Inc. | Polyester yarn production |
JPS5227815A (en) * | 1975-08-29 | 1977-03-02 | Teijin Ltd | Spinning pack |
-
1981
- 1981-04-30 EP EP19810301913 patent/EP0040482B1/en not_active Expired
- 1981-04-30 DE DE8181301913T patent/DE3165354D1/en not_active Expired
- 1981-05-07 BR BR8102826A patent/BR8102826A/en unknown
- 1981-05-12 CA CA000377438A patent/CA1162710A/en not_active Expired
- 1981-05-13 MX MX18728081A patent/MX154777A/en unknown
Also Published As
Publication number | Publication date |
---|---|
CA1162710A (en) | 1984-02-28 |
BR8102826A (en) | 1982-02-02 |
MX154777A (en) | 1987-12-11 |
DE3165354D1 (en) | 1984-09-13 |
EP0040482A1 (en) | 1981-11-25 |
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