US3659980A

US3659980A - Apparatus for melt spinning of synthetic filaments

Info

Publication number: US3659980A
Application number: US36031A
Authority: US
Inventors: Miguel A Fernandez
Original assignee: Phillips Fibers Corp
Current assignee: Phillips Fibers Corp
Priority date: 1970-05-11
Filing date: 1970-05-11
Publication date: 1972-05-02
Anticipated expiration: 1989-05-02

Abstract

Apparatus comprising an improved quench chamber wherein the side panels of said chamber are constructed so as to eliminate undesirable air currents. The side panels are adapted to be moved vertically, either individually or collectively, into and out of engagement with a spinning block.

Description

0 United States Patent [1 1 3,659,980 Fernandez 1 May 2, 1972 s41 APPARATUS FOR MELT SPINNING 0F 3,257,487 6/1966 Dulin ..l8/8 QM x SYNTHETIC FILAMENTS 3,080,607 3/1963 Bley 18/8 QD ux I 1,942,540 1/1934 Dreyfus et al. [721 Fernandez Greenvme 2,947,029 8/1960 Bakker ..1s/s QM [73] Assignee: Phillips Fibers Corporation Primary Examiner-J. Spencer Overholser [22] Ffled' May 1970 Assistant Examiner-Michael 0. Sutton [21] Appl- N0: 3 10 Attorney-Young and Quigg 52 us. c1 ..425/72, 425/192, 425/382 [571 ABSTRACT [51] Cl M 3/00 Dold 5/08 Apparatus comprising an improved quench chamber wherein 58 Field 61 Search ..1s/s QD, s QM; 264/176 F the Side panels of Said chamber are constructed so as m eliminate undesirable air currents. The side panels are [56] Rem-"Ices Cited adapted to be moved vertically, either individually or collec- UNITED STATES PATENTS tively, into and out of engagement with a spinning block. 3,067,458 12/1962 Dauchert ..18/8 QD UX 11 Claims, 5 Drawing Figures Patented May 2, 1972 2 Sheets-Sheet ll INVENTOR.

M. A FERNANDEZ ATTORNEYS APPARATUS FOR MELT SPINNING OF SYNTHETIC FILAMENTS This invention relates to apparatus for melt spinning of synthetic filaments.

Melt spinning, in general, comprises the extrusion of molten thermoplastic materials such as vinyl polymers, polyamides, polyesters, and polyolefins into separately formed filaments and the cooling of said filaments so as to promote solidification thereof by means of a stream of gas, e.g., air, directed against said filaments. The apparatus employed to cool said filaments is commonly referred to as a quench chamber or quench apparatus. Quench apparatus of the type commonly in service in the prior art comprises a vertical enclosure formed by a pair of vertically extending side panels and a foraminous back panel disposed between said side panels. The front of the chamber is usually open to the atmosphere. Said side panels are frequently hinged at their rear edges and extend upwardly to a point adjacent the spinning block. The filaments are extruded through a spinneret positioned in said spinning block and are passed downwardly through the quench chamber to a collecting convergence guide at the lower end of said chamber. A fluid under pressure, such as an inert gas or air, is forced through the pores in the forarninous back panel into the chamber and around the descending filaments so as to cool and harden same.

In the operation of said prior art spinning apparatus, considerable difficulties have been encountered with air turbulences created in the quench chamber by leakage of air between the top of the side panels and the bottom of the spin block, and between the rear edges of the side panels and the face of the machine, e.g. between the wall of the plenum chamber supplying gas to the forarninous back panel and the rear edges of the side panels. Said turbulences can be of two types, (a) actual eddy currents sufficient to cause excessive movement of the filaments and/or (b) currents of nonuniform temperature in the stream of air or other gas flowing past the filaments. The former (a) can actually cause sticking of the filaments. Either (a) or (b) can result in filaments of substandard quality, e.g., variable denier, nonuniform cross section, etc., resulting from uneven cooling of the filaments. Such irregularities, unevenness, or nonuniformity in the filaments results in a nonuniform yarn which will not dye uniformly. Du (see ASTM 1425) is the per cent mean deviation unevenness obtained on the Uster uniformity tester and is sometimes referred to in the trade as the Uster value.

The present invention provides a solution to the above problems by providing a quenching apparatus wherein said air turbulences are essentially eliminated.

An object of this invention is to provide an improved apparatus for the melt spinning of synthetic filaments. Another object of this invention is to provide an improved quench chamber which can be employed in the melt spinning of synthetic filaments. Another object of this invention is to provide an improved apparatus for melt spinning of synthetic filaments having uniform denier and uniform cross-sectional area. Another object of this invention is to provide an improved quench chamber for cooling and hardening synthetic filaments wherein undesired air currents within said quench chamber are eliminated. Other aspects, objects, and advantages of the invention will be apparent to those skilled in the art in view of this disclosure.

Thus, according to the invention, there is provided apparatus for the melt spinning and quenching of synthetic filaments comprising, in combination: a spinning block; a pair of elongated, spaced apart, generally parallel side panels movably positioned for vertical movement below said spinning block; an elongated foraminous back panel extending downwardly from said spinning block between said side panels; means for mounting said side panels for said vertical movement; and means for moving said side panels vertically into and out of engagement with said spinning block.

FIG. 1 is a front view in elevation, partly in cross section, of an improved melt spinning apparatus in accordance with the invention.

FIG. 2 is a side view in elevation of the apparatus'illustrated in FIG. 1.

FIG. 3 is an enlarged view, partly in cross section, taken along the lines 3-3 of FIG. 1.

FIG. 4 is a perspective view illustrating details of the panel engaging and disengaging means of the invention.

FIG. 5 is a diagrammatic illustration of a combination of a plurality of the quench chamber and associated elements illustrated in FIG. 1.

Referring now to said drawings, wherein like reference numerals have been employed to denote like elements, the invention will be more fully explained. In FIG. 1 the apparatus comprises a spinning block 10, a spinneret assembly 12 mounted in said spinning block, a pair of elongated, spaced apart, generally

parallel side panels

14 and 16 positioned below said spinning block, and an elongated foraminous back panel 18 extending downwardly from said spinning block between said

side panels

14 and 16. A pair of generally parallel spaced apart grooves 20 are formed in the underside of said spinning block on opposite sides of said spinneret assembly in general alignment with said

side panels

14 and 16, and are adapted to receive the upper ends of said side panels. Preferably, a resilient gasket means 22 is mounted in each of said groovfi 20. However, it is within the scope of the invention to omit said gasket means 22 and provide a close fit between the upper edges of said side panels and the inner wall of said grooves, or to provide a resilient gasket means on the upper edges of said side panels.

Means are provided for mounting said side panels for vertical movement. Preferably, said mounting means comprises a pair of spaced apart rail members 24 positioned at opposite transverse edges of said back panel 18. Said rail members extend longitudinally along and beside said transverse edges of the back panel, through floor 25 and into the story below. Each of said rail members comprises a base 26 having a tongue 28 extending forwardly therefrom. A groove 30 (see FIG. 3) is formed in the rear edge of each of said

side panels

14 and 16 and is adapted to engage the tongue of the rail member positioned adjacent said rear edge of the panel. Said rail members can be supported from the front of plenum chamber 52 (discussed hereafter), or in any other suitable manner.

Means are provided for moving said side panels vertically into and out of engagement with said spinning block. For example, a gear rack 32 is mounted on the rear edge of each of said side panels. A shaft 34, suitably supported by any conventional means, extends generally horizontally behind said

side panels

14 and 16. A pair of spaced apart pinion gears 36 are movably mounted on splines 35 on said shaft with each pinion gear being adapted to engage one of said gear racks 32. An engaging fork 38 extends around said shaft, is positioned on one side of said pinion gear, and is adapted to bear against said pinion gear. A lever means 40, suitably mounted on a pivot 42 is provided for moving said fork into engagement with said pinion gear 36 and move said pinion gear into engagement with said gear rack 32. A lock bar 43 extends from one side of said lever means 40 and is adapted to fit under the adjacent side panel and hold said side panel in elevated position when said pinion gear 36 is not in engagement with gear rack 32. A shoulder 44 is fixed to said shaft on the other side of said pinion gear 36. A disengaging spring 46 is mounted around said shaft between said shoulder and said pinion gear and is adapted to move said pinion gear out of engagement with said gear rack when said engaging fork is not bearing on the opposite side of said pinion gear. A reversible motor 48 or other suitable means is provided for rotating said shaft 34 by means of belt 50.

A plenum chamber 52 is disposed behind said back panel 48 and is adapted to receive air or other inert gas through inlets 54 for introduction through the pores of said back panel into the space or chamber defined by said side panels and said back panel. If desired, a conditioner tube 56 can be positioned in the lower portion of said chamber and extends through the floor 25 to the story below in conventional manner. A convergence guide 60 is mounted adjacent the upper end of said conditioner tube. Said rail members 24 also extend through said floor 25 into the story below. Any suitable means, not shown, can be employed for supporting said plenum chamber 52 and said spinning block 10.

Referring now to FIG. 5, there is shown a plurality of spinning blocks arranged in general horizontal alignment. A pair of said

side panels

14 and 16 is positioned below each of said spinning blocks. A back panel (not shown in FIG. 5) is positioned between each of the panels of said pairs of side panels. Each of said side panels is provided with the abovedescribed mounting means for enabling vertical movement of said panels. Said shaft 34 and other elements associated therewith in the means for moving said side panels vertically into and out of engagement with said spinning block are also provided in the apparatus of FIG. 5.

ln starting operation of the apparatus described above,

side panels

14 and 16 can be lowered vertically by moving lever 40 so as to disengage lock 43 from the bottom of said panels, cause fork 38 to bear on pinion gear 36, and move same into engagement with gear rack 32. Motor 48 is then started to rotate shaft 34 which will cause said side panels to be moved to a lowered position. A spinneret assembly 12 is then mounted in spinning block 10. Reversible motor 48 is then started to rotate shaft 34 in the opposite direction and the side panels are moved vertically into sealing engagement with the gasket material 22 in grooves 20 of spinning block 10. Motor 48 is stopped, and lever means 40 is moved so as to cause fork 38 not to bear on pinion gear 36. Disengaging spring 46 will then move said pinion gear out of engagement with gear racks 32. Movement of lever 40 also places lock 43 into position under the bottom of the raised side panels. Spinning operations are then started in conventional manner. If it becomes necessary to suspend said spinning operations and work on the spinneret assembly, or for any other reason, said side panels can be lowered as described above. It will be noted that said side panels can be lowered individually by operating only one of the levers 40 and pinion gears 36.

A number of advantages are obtained or realized when employing the apparatus of the invention. All stray air leaks into the quench chamber are essentially eliminated. Thus stray air currents from the room in which the apparatus is located cannot leak into the quench chamber above the top edges of the side panels, or along the rear edges of said side panels. The air stream flowing outwardly from back panel 18 effectively prevents stray currents from entering through the open front of the machine. Elimination of said stray air currents provides filaments of essentially uniform denier and essentially uniform crosssectional area, i.e., filaments having low percent Uster.

In addition, numerous advantages in the operation and maintenance of the apparatus are realized. For example, each of the

side panels

14 and 16 can be moved vertically into and out of engagement with the spin block 10, either individually or collectively. The movement of a single side panel or a pair of side panels is particularly advantageous when it is desired to work on only one machine or unit. The movement of a plurality of pairs of side panels collectively, such as in the apparatus illustrated in FIG. 5, is particularly advantageous when starting up a plurality of units at one time. This facilitates pack or spinneret assembly installation. Slow pack or spinneret assembly installation results in cold packs that do not allow proper polymer flow and must be replaced. The improved design of the apparatus of the invention, by facilitating lowering of the side panels, provides more room for the installation of the spinning packs or spinneret assemblies. Replacing of the quench screens on the back panel 18 is easier than in the conventional apparatus. When difficulties are encountered with one spinneret assembly, the single unit involved can be shut down, the side panels lowered, and the defective spinneret cleaned or replaced much more easily without disturbing the other units. Still another advantage is that the apparatus can be designed with side panels of one unifonn length. In apparatus of the prior art, variable side panel lengths are required depending upon the denier and yarn count of the filaments being spun. In the apparatus of the invention a single set of side panels can be employed for each unit and the effective length of the quench chamber can be changed by raising or lowering an extendable conditioner tube 56 and blanking off the unneeded portion of back panel 18.

it will be understood that the drawings are diagrammatic in nature. Thus, if desired, and as will be understood by those skilled in the art, suitable sealing means can be provided around conditioner tube 56 and rail members 24 where these elements pass through floor 25 so as to maintain proper pressure differential between the story above floor 25 and the story below floor 25. Similarly, the motor 48 has been illustrated as installed below floor 25. If more convenient, said motor 48 can be installed on or above floor 25.

The following illustrative examples are calculated examples based upon past experience in the melt spinning of synthetic filaments. Said examples are considered to be representative of results obtained in the prior art and results which can be obtained in the practice of the invention.

EXAMPLE I A polypropylene with l2 melt flow (ASTM D 1238-621) is spun in a spin block with conventional air quench chamber through a 34 hole spinneret with 0.030 inch diameter hole x 0.090 inch long. Spinning temperature is 275 C. with a throughput of 2 grams/minute/hole or 68 grams total. Spinning speed is 318 meters per minute with a total denier of 2040. Quench air at 24 C. is used to cool the filaments at a velocity of 75 feet per minute and a relative humidity within the range of 30 percent to 50 percent. Draw ratio is 4/ l to a 15 denier per filament. Uster value is 2 percent.

EXAMPLE II The same polypropylene is spun under conditions as described in Example I but employing the improved apparatus of this invention wherein stray air currents are eliminated. Uster values of 1 percent are obtained.

EXAMPLE H] A polyhexamethylene adipamide (Nylon 66) having a melt viscosity of about 800 poises is spun, employing the improved apparatus of this invention, through a spinneret having 20 holes of 0.006 inch diameter. The spinning temperature is maintained at about 285 C. The spinning speed is 1,800 feet per minute. The filaments are quenched in the improved quench chamber of the invention using air at 24 C. as the quenching or cooling medium at a velocity of feet per minute. The total denier is 175. The draw ratio is 4/1. Uster value is 1 percent.

While certain embodiments of the invention have been described for illustrative purposes, the invention obviously is not limited thereto. Various other modifications will be apparent to those skilled in the art in view of this disclosure. Such modifications are within the spirit and scope of the invention.

I claim:

1. Apparatus for the melt spinning and quenching of synthetic filaments comprising, in combination: a spinning block; a quench chamber comprising a pair of elongated, spaced apart, generally parallel side panels movably positioned for individual or simultaneous vertical movement below said spinning block, an elongated foraminous back panel extending downwardly from said spinning block between said side panels, and an open front generally opposite said back panel; a plenum chamber disposed behind said foraminous back panel and adapted to receive quenching medium for introduction through said back panel into said quench chamber; means for mounting said side panels for said vertical movement; and means for moving said side panels vertically into and out of engagement with said spinning block.

2. Apparatus according to claim 1 wherein: sealing means are provided in said spinning block for engaging the upper ends of said side panels.

3. Apparatus according to claim 2 wherein said sealing means comprises a pair of generally parallel spaced apart grooves fonned in the underside of said spinning block and adapted to receive said upper ends of said side panels.

4. Apparatus according to claim 3 wherein a resilient gasket is mounted in each of said grooves.

5. Apparatus according to ciairn 1 wherein said mounting means for said side panels comprises a pair of spaced apart rail members positioned at opposite transverse edges of said back panel with each of said side panels being adapted to movably engage one of said rail members.

6. Apparatus according to claim 5 wherein: each of said rail members comprises a base having a tongue extending forwardly therefrom; and a groove adapted to engage a said tongue is formed in the rear edge of each of said side panels.

7. Apparatus according to claim 1 wherein said means for moving each of said side panels comprises: a gear rack mounted on the rear edge of each of said side panels; a shaft; a pair of spaced apart pinion gears movably mounted on said shaft, each being adapted to engage one of said gear racks; means for moving each of said pinion gears into and out of engagement with one of said gear racks; and means for rotating said shaft.

8. Apparatus according to claim 7 wherein said means for moving each of said pinion gears comprises: an engaging fork extending around said shaft on one side of and adapted to bear on one side of said pinion gear; lever means for moving said fork against said pinion gear and moving same into engagement with said gear rack; a shoulder fixed to said shaft on the other side of said pinion gear; and a disengaging spring mounted around said shaft between said shoulder and said pinion gear and adapted to move said pinion gear out of engagement with said gear rack when said engaging fork is not bearing on the opposite side of said pinion gear.

9. Apparatus according to claim 1 wherein: a spinneret assembly is mounted in said spinning block; said side panels are positioned on opposite sides of said spinneret assembly; a pair of generally parallel spaced apart grooves are formed in the underside of said spinning block on opposite sides of said spinneret assembly in general alignment with said side panels and are adapted to receive the upper ends of said side panels; a resilient gasket is mounted in each of said grooves; said mounting means for said side panels comprises: a pair of spaced apart rail members positioned at opposite transverse ends of said back panel, each said rail member comprising a base having a tongue extending forwardly therefrom, and a groove adapted to engage a said tongue formed in the rear edge of each of said side panels; and said means for moving each of said side panels comprises: a gear rack mounted on the rear edge of each of said side panels, a shaft, a pair of spaced apart pinion gears movably mounted on said shaft with each being adapted to engage one of said gear racks, an engaging fork extending around said shaft on one side of and adapted to bear on one side of said pinion gear, lever means for moving said fork into engagement with said pinion gear and moving same into engagement with said gear rack, a shoulder fixed to said shaft on the other side of said pinion gear, a disengaging spring mounted around said shaft between said shoulder and said pinion gear and adapted to move said pinion gear out of engagement with said gear rack when said engaging fork is not bearing on the opposite side of said pinion gear and means for rotating said shaft; and a conditioner tube is positioned in the lower portion of the space or chamber defined by said side panels and said back panel.

10. Apparatus according to claim 1 wherein there is provided: a plurality of said spinning blocks arranged in general horizontal alignment; a pair of said side panels is positioned below each of said spinning blocks; and a said back panel is positioned between each of the panels of said pair of side anels. p 11. Apparatus according to claim I wherein: a vertically extendabie conditioner tube is positioned in the lower portion of the space or chamber defined by said side panels and said back panel; and a convergence guide is mounted adjacent the upper end of said conditioner tube.

t i i l i

Claims

3. Apparatus according to claim 2 wherein said sealing means comprises a pair of generally parallel spaced apart grooves formed in the underside of said spinning block and adapted to receive said upper ends of said side panels.

5. Apparatus according to claim 1 wherein said mounting means for said side panels comprises a pair of spaced apart rail members positioned at opposite transverse edges of said back panel with each of said side panels being adapted to movably engage one of said rail members.

10. Apparatus according to claim 1 wherein there is provided: a plurality of said spinning blocks arranged in general horizontal alignment; a pair of said side panels is positioned below each of said spinning blocks; and a said back panel is positioned between each of the panels of said pair of side panels.

11. Apparatus according to claim 1 wherein: a vertically extendable conditioner tube is positioned in the lower portion of the space or chamber defined by said side panels and said back panel; and a convergence guide is mounted adjacent the upper end of said conditioner tube.