US 3274644 A
Description (OCR text may contain errors)
sept. 27, 1966 W, M MASSEY ETAL 3,274,644
ADJUSTABLE PROFILE CHIMNEY Filed April 27, 1964 5 Sheets-Sheet 1 BY @wv-CA( ATTORNEY Sept. 27, 1966 wI M, MASSEY ET AL 3,274,644
ADJUSTABLE PROFILE CHIMNEY Filed April 27, 1964 sheets-sheet s il j? :n mo o g5 a n o o J\ oo o j woo 00 O 1 go (NUC) x' .i
` INVENTORS MLU/9M Moopf Mme-@E5 B/LJ. JCU/2E,
ATT RNEY United States Patent O 3,274,644 ADJUSTABLE PRFILE CHIMNEY William Moore Massey, Signal Mountain, and Bill L.
Pope, l-lixson, Tenn., assigncrs to E. l. du Pont de Nemours and Company, Wilmington, Del., a corporation of Delaware Filed Apr. 27, 1964, Ser. No. 362,908
4 Claims. (Cl. IS-S) This invention relates to the melt spinning of synthetic filaments from polymeric materials. More particularly, it relates to an improved apparatus for quenching molten filaments in which various conditions of flo-w of the cool- 4ing fluid may be established for efficient contact with the moving filaments.
In the melt spinning of filamentary materials of polymeric nature such as polyhexamethylene adipamide and the like, the molten polymeric material is extruded through a spinneret into a Zone where it is quenched by a flow of gaseous medi-um. One type of apparatus for this purpose is described in Heckert U.S. 2,273,15 to Du Pont in which the quenching medium is directed from a plenum chamber transversely across the path of the molten filament in a quenching zone. Scheers, U.S. 2,847,704 discloses a tubular quenching apparatus in which the quenching medium flows upwardly and counter to the descent of molten filaments. Babcock, U.S. 2,252,684, reveals a quenching apparatus which is also tubular, but the coolant is admitted near the spinneret and travels down the vertical tube cocurrently with the freshly spun descending filaments. Various modifications and refinements of quench-ing apparatus have been devised; but, in each instance, quenching is limited to one of the three above conditions: crossflow, counter-current or cocurrent. Adjustment may be made in the total volume or velocity of quenching medium, but a change in the flow pattern of the quenching medium with respect to the threadline may only 4be made by a complete replacement of the major components of the quenching apparatus. Such replacement is time-consuming and costly when one wishes to change the composition, size, cross-section or other property of the filaments being produced on a melt spinning machine and a change in the flow `of the quenching medium is required to accommodate the new conditions.
A primary object of this invention is to provide a-n improved apparatus for use in melt spinning of synthetic fibers. Another object is t-o provide accurate control of the entry and discharge of a cooling medium into and out of a quenchnig chamber. It is also an object of this invention, to provide an improved quenching chamber in which the direction and velocity of flow of the cooling medium m-ay be adjusted at will. A further object is to provide a wide range of quenching conditions to permit the melt spinning of a variety of filamentous materials. Another objeot is to provide a convenient means for making adjustment to obtain the desired flow of cooling medium in the quenching chamber. These and other objects will .become apparent in the course of the following descrip- `tion and claims.
According to the present invention, an improved quenching system is provided which comprises first of all an oblong air-supply duct or manifol extending length- Wise beside a bank of lined-up spinnerets. Along the upper wall of said manifold `are spaced a plurality of plenum chambers each of which extends lengthwise sufficiently to face a convenient plurality of said spinnerets. Each plenum receives a supply of .air (or other convenient gaseous cooling medium) through one or more restricted openings in the top of said duct, referred to hereinbelow as restrictorsf Along the vertical wall of each plenum on the outside are attached a plurality of quenching chambers or chimneys corresponding to the number of spin- ICC nerets desired to serve from said plenum (on that side). Each chimney comprises vertical Walls and a top and a bottom provided with suitable openings so that the bundle of filaments extruded from one spinneret can move downwards into and out of the chimney space wit-hout touching its walls. `On the vertical wal-l portion which each chimney shares with its plenium is an inlet panel for passing gaseous cooling medium from the plenum into the quenching chamber. On the wall opposite the inlet panel is an outlet panel for the gaseous medium.
Now, as a particular feature of this invention, said inlet panel and outlet panel of each quenching chimney are made up of a plurality of adjacent, horizontally disposed sections and each of said sections contains means for individually setting it to transmit a stream of said gaseous fluid of an optional strength, from zero value to the full strength of the stream being brought to bear upon said panel, whereby any and all of the following effects may lbe achieved:
(a) The stream of gaseous fluid passing through any section of said panel may be regulated independently of the setting of any of the other sections;
(b) The sum total of gaseous stream passing through said panel at any given time may be controlled;
(c) The average location of the total stream passing through each panel with reference to the height of the quenching chamber may be controlled; and
(d) By selecting ydifferent locations (c) for the stream coming into the chamber through the inlet panel and that going out through the outlet panel, the average direction of the gaseous stream within the quenching chamber as it contacts said descending plurality of filaments may be controlled to have essentially a cocurrent, countercurrent or transverse character with respect to the descending bundle of filaments.
The invention will be more readily understood by reference to the drawings.
FIGURE 1 is a perspective view in partial crosssection of a quenching chamber and associated supply duct and plenum.
FIGURE 2 is a perspective view, partly in section, of a preferred embodiment of the flow controlling panel used in this invention.
FIGURE 3 is a side view, partly in section, of the quenching chamber of FIGURE 1, and shows, incidentally, one pattern of flow of the quenching gas through the chamber.
FIGURES 4 and 5 are diagrams of two other patterns of flow of the quenching gas, which m-ay be obtained with the apparatus of this invention.
FIGURE 6 is a perspective view of one of the valves used in the inlet panel of the novel quenching chamber.
Referring to FIGURE 1, the quenching apparatus comprises a supply duct 11, a restrictor 12, a plenum lf3, an inlet valve panel 14, a quenching chamber 15, and an outlet valve panel 16. FIGURE 1 -shows one of a multiplicity of quenching stations .in apparatus for spinning several yarns simultaneously. The quenching medium is supplied to duct 11, from a conventional pressure `distribution system, not shown, through openings regulated by damper 17. Restrictor 12 is positioned in an opening in a common wall 18 between lsupply duct -11 and plenum 13. Valve panel 1-4 is located in an opening of suitable size and shape l19 in each side Iwall 20 of plenum 13. The `quenching chamber or chimney 1'5 is enclosed by said vertical inlet valve panel 14, outlet valve panel 16, two imperforate side walls 21 and top and bottom walls v26 and I27 (shown on the left side of FIG. 1). The side -walls 21 and outlet panel 16 are generally hinged and latched or detachably mounted on plenum wall 20 -to provide ready access to t-he threadline for convenient assembly and servicing of the apparatus.
It will be understood th-at supply duct 11 can be, and generally will be made long enough to serve a long bank of spinning positions, and may therefore have a plurality of dampers 17 along its length. YThe plenums 13 are generally shorter than the d-uct and there will therefore be a plurality of lthem lengthwise of the duct, adjacent plenums being separated by vert-ical partitions (not shown in FIG. 1). Each plenum Will support a plurality of quenching chimneys (say 2 to 8 on each side), and Will in t-urn be served by at least one, and possibly two to four restrictors 12.
Furthermore, in practice a single oblong air duct may be constructed to serve two banks of aligned spinnerets, one bank on each side of the d-uct. In such event, the details shown in FIGS. 1 to 6 of the drawings apply .also to the structure on the left side of the duct, except that they are reversed, in mirror image fashion, with respect to the details shown for the right side. I
The liow of air through the entire system is. best understood by studying FIGS. 1 and 3 jointly. The quench-ing medium, usually air, is supplied .under positive pressure to duct 11. Duct 11 senves as an ante-chamber, minimizing the kinetic energy influence in the total supply of fluid to the quenching apparatus. The static pressure along the length of duct 11 is equalized by adjusting each damper 17 to properly balance the system according to measurement of press-ure under flow conditions with manometers, gauges, flow meters or other devices well known in the fluid flow art. The quenching fluid flows from supply duct 11 to plenum 13 through restrictor 12. The restrictor serves two important functions in a minimum of space, metering and diffusing of the quenching fluid into the plenum which in turn serves as a supply for the individual quenching chambers. The fluid flows from plenum 13 through the valve openings in valve pane-l 14 and a foraminous sheet 22 into quenching chamber 15. After passage through the quenching chamber, the fiuid discharges through the open valves in p-anel 16 into the atmosphere surrounding the spinning apparatus. \In this diagram, freshly-spun filaments 26 are shown entering the top of the quenching chamber 1'5 from a sp-inneret 24, descending to a convergence guide 25, and pass-ing downwardly through a sui-table opening to the windup or next -stage in fiber processlng.
The restrictor .12 is a hollow, perforated cylindrical body. A circular cross-section is shown, but other forms such as elliptical, rectangular-or polygonal serve equally well. `Multiple orifices perforate the walls in the entrance or upstream region of the restrictor. Preferably, these orifices are of equal size, approximately 1/2 to 1% inch (13 to 19 mm.) diameter being suitable dimensions. The number of oriiices is selected to provide a pressure difierential ,for maximum iiow in the range of 3 inches to 4 inches water gauge (0.0075 to 0.010 atmosphere). This pressure drop is suicient to minimize the effect of the approach velocity at maximum liow and to provide a measurable resistance at low iiows, say 50% of maximum. In an installation of several quenching stations, each restrictor is .calibrated to a standard flow by measurement of liow res-istance with conventional manometers to assure uniformity of (dow and to permit interchangeability. The air exits from the restrictor through multiple perforations in a diffused pattern at a velocity not exceeding 1,000 ft. per minute (305 meters per minute) to minimize turbulencein the plenum chamber and eliminate stray high-velocity currents which would upset flow to the quenching chambers.
The flow of lair into the quenching chamber is regulated by valve panel 14. This novel apparatus, .shown in perspective in FIGUIRE 2, comprises a cellular assembly in which each compartment is of like size and shape. In the plane of the vertical upstream wall, each compartment has an inlet opening 30, fitted with a flow-regulating Valve 32. On the downstream ends, the compartments terminate in a vertical foraminous sheet 22. The over-all size of the valve panel and the number of cells inthe panel may be varied according to the size of the quenching chamber to be supplied and the desired flow patterns. The particular embodiment shown in FIG. 2 is rectangular in form, planar Wall 33 being the inlet wall, flat walls 34 and 35 (shown cut away) being side walls, and shelves 36 serving as partitions between cells. The cells may readily take other geometric forms such as cylindrical, conical, hemispherical, parabolic and others, although this may increase the fabrication cost.
A simple valve means 32 is shown in FIG. 6. It is a manually-operated push-pull device, comprising a plug 3-'7 with a metering orifice 318 and cap 39 connected by spaced staves 32-1, fitted in opening 30 in the upstream inlet wall 313. Air `flow in each horizontal cell is regulated manually by positioning the valve in an open or closed position by the aid of handle 39d.
One valve is shown in each cell in FIG. 2, but the number of valves in each cell may be Varied as desired. In particular, two or three valves may be inserted sideby-side in the upstream wall of each horizon-tal compartment. Each valve contains a metering orifice 38, whose size determines the quantity of flow through said valve when the latter is set in its open position, but the orifices are preferably of different sizes lin the two or three Valves which serve the same horizontal compartment. Then, in the case of three valves, for instance, one may set into the open positions (a) none, (b) a selected one, (c) any desired combination of two, or (d) all three valves, and thereby produce an iniiow of cooling air into any given .compartment of a magnitude varying by steps overa wide range.
Our invention, however, is not limited to the particular style of valve described above, and in lieu thereof any known valve means may be used, such :as a simple plug, a screw throttling valve, a slideable shutter, an adjustable iris or an electrically operated solenoid, and the like.
The foraminous sheet 22 serves as a diffuser to distribute the quenching gas evenly from side to side in the quenching chamber. The diffuser may be designed for individual cells or may be large enough for the entire valve panel, depending upon the physical size for practical handling and may be extended into the cells or cover the face of the cells. The diffusers have a perforated free area of approximately 30 to 50% of the total face area. The perforations may be round, rectangular or elongated slots arranged in a regular or staggered pattern. The perforations may be as large as 1/s inch (3.2 mm.) in diameter or width. The size and pattern of the holes must satisfy three basic requirements:
(1) The quenching gas from each cell must be evenly distributed across the face of each cell, regardless of the location and number of valves;
(2) The individual openings must be large enough to minimize any tendency to accumulate fine particles of dust or other foreign particles which are normally encountered in quenching gas;
(3) The openings must permit passage of the quenching gas without jetting and disturbing the filaments being quenched.
Valve panel 16 constitutes one wall of the chimney, at the side opposite inlet panel 14. A preferred embodiment is a louvered door in which horizontal louvers of equal Size are arranged vertically in the panel and each louver may be 'adjusted individually from fully closed to fully open positions. The length and width of the panel are defined by the desired size of the quenching chamber. The size of the louvers is important only in that the blades should be relatively narrow, to provide many selections for the outgoing fiow pattern and to avoid interference with the threadline or operator functions. Generally, the louvers should extend the full width of the door and have a vertical dimension of about 1/3 of the door width. The louver blades maybe transparent to permit visual inspection of the threadline during operation` Loking means are provided to hold the louvers in the desired orientation during operation. The entire valve panel is most conveniently used when hinged along one edge to side wall 21 and latched in the closing position along the opposite edge with a magnetic or hook latch, thus providing ready access to the interior of the quenching chamber.
Equally convenient mechanical alternatives may be used for fabrication of the discharge valve panel such as those described for use in the inlet valve panel. For example, a perforated or slotted sheet with slideable shutters may be used with equal effectiveness.
Any conventional materials of construction may be used for fabrication of the valve panels and associated quenching apparatus. Metals such as steel, aluminum, brass or copper are most commonly used. Valve components, louvers, slides and shutter components may also be made of die cast metallic alloys or molded of plastic materials.
The apparatus of this invention permits a wide variety of quenching conditions to suit the requirements of the fiber being spun. Thus, FIG. 4 illustrates a setting of panels 14 and -16 which provides a cross-ow of quenching gas in the vertical chimney. All valves in valve panel 14 and all louvers in wall 16 are open, thus providing equal flow velocity throughout the height of the panel. This embodiment has a free and open discharge of the quenching gas and therefore provides simple transverse ow of the gas with respect to the threadline. The velocity pattern of the quenching gas through the filament bundle may be altered by appropriate setting of the valves in the valve panel, as may be required by the filament being extruded into the chimney. Thus a relatively high velocity may be obtained in the upper part of the chimney and a relatively low velocity in the lower region, or viceversa.
In FIG. 3, the panels are set to produce a cocurrent liow of the quenching gas. By opening only a few valves in the upper portion of inlet panel 14 and opening only a few valves in the lower portion of panel 16, the quenching gas in the chamber is made to enter at the top, take a downward path parallel to the travel of the lilaments and exit in the lower region.
FIGURE 5 illustrates a counter-current ow of quenching gas, also obtainable with the same apparatus by a simple adjustment. By opening valves in the lower region of the inlet panel 14 `and opening valves in the upper portion of outlet panel 16, the quenching gas liows from the bottom upwardly in chimney 1S in a direction opposite filament travel.
The apparatus of this invention has several advantages over spinning apparatus of the prior art:
(l) Precise regulation of the flow of quenching gas can be obtained in melt-spinning apparat-us.
(2) Many dilerent liow patterns can be obtained in a single apparatus to meet the requirements of different spinning conditions such as different iilament deniers, spinning speeds, lament configurations and various polymers.
(3) Quenching patterns can be varied for experimentation at a single quenching station without upsetting quenching conditions in other quenching stations on a full production machine.
The apparatus of this invention also has potential use for other fluid treatments of moving ilamentary materials. The treating fluid may be heated or at low temperature, inert or reactive with the iilaments. A lluid mist or a solvent vapor may, for example, be employed to produce a surface effect upon the ilaments. Many other variations in the details of this invention will be readily apparent to those skilled in the art.
We claim as our invention:
1. In combination with apparatus for cooling textile filaments formed by extruding molten film-forming material through a spinneret, a quenching chamber comprising essentially vertical inlet and outlet panels for allowing a gaseous cooling medium to pass through said chamber, and means for passing the extruded filaments vertically downwards through said chamber, each of said inlet and outlet panels comprising a plurality of adjacent, horizontally disposed sections and each of said sections containing means for individually regulating the stream of said gaseous cooling medium passing through said section, whereby both the total strength of the gaseous stream going through the quenching chamber and its general direction as it contacts the descending plurality of ilaments may be regulated.
2. A quenching chamber as in claim 1, said outlet panel being made up of a plurality of adjacent, individually adjustable louvers, supported in a common frame by means permitting each louver to swing independently on a horizontal axis.
3. A quenching chamber as in claim -1, said inlet panel being made up of a plurality of vertically spaced horizontal shelves supported at the ends in vertical walls whereby to form a vertical stack of independent horizontal passages through said panel, and each of said horizontal passages being closed up on its upstream side except for one or more openings containing a valve, said valves being ladapted to be set independently in one of at least two positions, whereby to control the strength of total gaseous stream admitted into said inlet panel for transmission into said quenching chamber.
4. A quenching chamber as in claim 3, said plurality of horizontal passages being covered up on the downstream side by a foraminous sheet adapted to diffuse the streams of air passing through it.
References Cited by the Examiner UNITED STATES PATENTS 1,541,104 6/1925 Briggs et al. 18-8 2,289,860 7/ 1942 Babcock 18-8 XR 3,067,459 12/ 1962 Brand 18-8 3,070,839 1/1963 Thompson 18-8 3,108,322 10/1963 Tate 18-8 WILLIAM J. STEPHENSON, Primary Examiner.