US2484882A

US2484882A - Spinning bucket compartment humidifier

Info

Publication number: US2484882A
Application number: US9995A
Authority: US
Inventors: Hugh D Haley
Original assignee: American Viscose Corp
Current assignee: Akzo Nobel UK PLC
Priority date: 1948-02-21
Filing date: 1948-02-21
Publication date: 1949-10-18
Anticipated expiration: 1966-10-18

Description

an E figfi o H HALEY 2 44 2 SPINNING BUCKET COMPARTMENT HUMIDIFIER Filadi'eb. 21, 194.8- 2 Sheets-Sheet l INVENTOR. HUQH .0. HALE Mi a Q42? 1,, 1% H. HALEY flg z SBINKQING BUCKET COMPARTHENT HUMIDIFIER -Filad m. 21, 1948 2 Sheets-Sheet 2 f W maimaw ak INVENTOR. HUG/ 7 D. HALE Y Patented Oct. 18, 1949 SPINNING BUCKET COIVIPARTMENT HUMIDIFIER Hugh D. Haley, Drexel Hill, Pa., assignor to American Viscose Corporation, Wilmington, Del., a

corporation of Delaware Application February 21, 1948, Serial No. 9,995

16 Claims. 1

This invention relates to a process and apparatus for humidifying compartments such as those housing rayon spinning buckets. The invention is primarily concerned with the prevention of crystal formation such as encountered in the collecting of freshly extruded filaments by the viscose process.

At one stage of the viscose process, viscose solution may be extruded as a multi-filament strand into a coagulating solution and conducted continuously therefrom over godets into a bucket spinning apparatus wherein it is collected as a cake. The wet strand carries coagulating solution into the spinning bucket wherein excess solution is subjected to centrifugal force and thrown into the region or onto the walls of the compartment surrounding the buckets. The high rotative speed of the bucket causes strong currents in the atmosphere within the compartment which promote evaporation of the liquid materials and the build-up of deposits of salts dissolved therein on surfaces Within the compartment. The formation of a slight deposit on the outer surface of the bucket increases the circulation of the atmosphere and consequently the rate of deposition of dissolved materials. Formation of solids on the bucket also results in an appreciable absorption of additional energy required to rotate the bucket. Moreover, particles of the solid materials drop into the bucket and damage the filamentary material.

The desirability of having high humidity in the atmosphere about the spinning bucket to minimize deposition of solids or crystals has been recognized for many years, and such expedients as refrigerating the walls of the spinning bucket compartment to obtain high relative humidity, and spraying the exterior of the bucket with water or steam, have been advanced. One of the most successful humidifying arrangements to be tried, is spraying a mist of a liquid such as water into the compartment, but even this method has attendant to it the danger of introducingthe spray liquid into the filamentary material and altering the characteristics, particularly the dyeing properties, thereof.

.It is an object of this invention to provide a method and apparatus for humidifying the atmosphere in a spinning bucket compartment or other enclosure. It is also an object to prevent the deposition of solid and/or crystalline mate rials in a spinning box compartment. It is another object, whileaccomplishing the aforesaid objects, to prevent the interchange of gases between the compartment and the atmosphere surrounding the compartment. A further object is to produce uniform filamentary materials of high quality. Other objects and advantages will be apparent in the following description of the invention and the drawings.

In the drawings illustrative of the invention,

Figure 1 is a partial fragmentary section of a spinning bucket compartment assembly;

Figure 2 is a partial fragmentary section of a spinning bucket compartment assembly showing a modified closure for the compartment;

Figure 3 is a fragmentary top view of the closure shown in Figure 2;

Figure 4 is a transverse section of another modified closure; and

Figure 5 is a fragmentary view, partly in section, of a spinning bucket compartment illustrating an alternative arrangement for carrying out the invention.

According to the invention, high relative humi dity is maintained in a spinning bucket compartment by providing an eflicient evaporating surface on an inner wall thereof, preferably on the inner side of the top closure therefor, and providing passageways from the exterior of the compartment for distribution of a liquid to the evaporating surface. For most efiicient operation of humidifying apparatus of this type, lower gas pressure is maintained within the compartment than exterior thereto.

A spinning bucket compartment assembly is shown in Figure 1 mounted in a housing 6 which may contain many such assemblies in an alignment perpendicular to the section plane. The assembly of a single spinning unit includes a spinning bucket 8, a shield l0, an upper closure 12, a drive shaft I4 for the bucket 8 and a driving means such as an electric motor (not shown). The housing is provided with sloping floor I! to facilitate drainage of coagulating solution which drips from the inside surface of the shield Ill. The housing 6, shown only in fragmentary section, is a substantially gas tight chamber to which vacuum may be applied to produce a reduction in pressure in the atmosphere about the spinning bucket 8. As objectionable and toxic gases are formed during the collecting of a strand within the bucket compartment, and the rotation of the bucket produces gas pressure in the up er portion of the compartment which tends to unseat the closure I2, and force the gases into the space occupied by workmen, vacuum applied to the strand collecting assembly is extremely useful in removing unwanted gases as well as aiding in carrying out the other objects of the invention.

According to the specific embodiment of the invention shown in Figure 1, an annular gasket or wick of absorbent material such as wool, felt, or a mat or fabric of any acid-resistant natural or synthetic fiber, is secured to the underside of the closure l2. To help hold it in place, a radially inwardly extending flange forms an annular recess 23 into which the outer ed e of the gasket 20 is inserted. If it is desired to obtain more positive attachment. the gasket may be cemented by its upper surface to the lower surface of the closure.

Another gasket 25 is provided about the portion of the periphery of the closure which supports the closure when in place. The gasket 25 fits into an annular recess formed by the outwardly extending radial fiange'21 and the shoulder 28. This gasket engages the edge of the compartment aperture and serves as a seal when there is a difference in gas pressure on opposite sides of the closure. As there is considerable tendency for solids, particles, or crystals to collect at the engaging surfaces and destroy the effectiveness of the seal or fall into the bucket, the gasket may be made of an absorbent material similar to that of the gasket 20 and moistened by the liquid supplied to the gasket 20. However, if a more durable material is desired, the gasket 25 may be readily formed from a vulcanized composition containing rubber or a vulcanizable rubber-like polymerizate.

For supplying liquid to the

gaskets

20 and 25, an annular groove is provided on the top side of closure l2. Holes 32 and 33 are drilled at regular intervals along the grooves so that the liquid may be uniformly distributed to the various sections of the grooves. The holes 32 and 33 are of sumciently small bore that when a stream of liquid suficient to nearly saturate both gaskets is supplied to the groove 30, the liquid does not all flow into some of the holes 32 and 33 before reaching the remainder of the holes. The size of the holes when drilled at intervals of one sixth to one eighth the circumference taken along the middle of the groove may vary in the range of 0.01 to 0.05 of an inch; this range. however, is not critical. A small annular ridge 35 extending upwardly from the outer edge of groove l2 prevents liquid from splashing or overflowing from the groove 30. Handles 39 are provided for the convenience of workmen in handling the closures.

The closure I 2 has a central aperture 31 through which a spining tube 38 reciprocates in vertical movement. In order to prevent excessive gas flow into the bucket compartment, particularly into the region of the evaporating surface on the gasket 20 and to obtain full advantage of the lower gas pressure produced by the vacuum, a washer 40 having a bore of suflicient diameter to permit freely reciprocating motion of the tube 38 is supported over the aperture 31 in an annular channel 4| formed so as to permit the washer 40 limited horizontal motion in all directions but practically no vertical movement. The washer 40 is formed of 4 a flexible material such as a vulcanized composition containing rubber or synthetic rubber, so that it may be inserted into the channel 4! through the flange of smaller diameter than the washer.

At least one liquid supply means, such as the tube 45, supported at swivel joint 46 furnishes liquid to the distributing groove 30. Fluid may be fed continuously, and controlled by a means such as the valve 48.

In Figure 2 is shown another embodiment of the invention illustrating a spinning bucket closure and a housing for supporting spining units. In Figure 2, the numerals of Figure 1 will be used on modified parts having the same function except that the letter a is added to the numeral for use in Figure 2. Closure I20. differs principally from closure i2 of Figure 1, inthat it has a larger central bore and the evaporating surface has been greatly increased by providing a gasket 20a which extends over the greater part of the under side of the closure and through the bore thereof. The gasket 20a is composed of, an absorbent material of sufiicient' flexibility that the central portion having an upper flange 50 may be forced through the bore of the closure in spite of the larger diameter of flange 50; with the outermost edges pressed into the channel 230., the gasket is firmly attached to the closure. However, a retaining ring 5!, attached by screws 52, may be employed to give additional support to the gasket, and/ or it may be cemented into place.

A central passageway 54 through the gasket 20a has a slightly greater diameter than the spinning tube 38 in order to provide an average clearance about the tube 38 of a few hundredths of an inch. This clearance, especially when it is increased according to the gradual taper shown in Figure 2 in the upper part of the passageway, permits a rapid current of air to flow into the compartment along the clearance when a reduced pressure exists within the compartment. The thin stream of rapidly moving air picks up. moisture as it passes the moist walls of the passageway. In this manner, a high humidity is imparted to the air which enters the compartment along the spinning tube. In order to get liquid into the central portion of gasket 20a, an annular groove 30a receives liquid from a flexible tube 55. Another annular groove 57 encircles the central portion of the closure I 2a and is connected with the concentric groove 30a by a plurality of radially extending grooves 58. A plurality of small holes intersecting the surface of the gasket 20a. carry the liquid from the intercommunicating

grooves

30a and 58.

A further modification of a closure [2b, is shown in Figure 4 wherein the proportions and shape of a gasket 20b have been varied over that shown in Figure 3. A single gasket has now been substituted to serve the purposes of the two gaskets used on each of the earlier described closures l2 and I 2a. The gasket 20b is supported and positioned by a ring 62 and screws of non-corrosive material.

In the various embodiments herein described and illustrated it is satifactory if excessive liquid supplied to the absorbent wicks or gaskets drains or drips to the surface of lid 43 of the spinning box 8. It is important, however, that none of the liquid actually enters the box as through an aperture in the center of the lid 43 provided for the stem of spinning funnel 38 since in this event the filamentary material being collected in the box 8 might be adversely affected. The liquid reaching the surface of lid 43 very efliciently aids in the control of crystal formation since it is thrown by centrifugal force to the side walls of the compartment and crystal-forming liquor is washed by such liquid down the surfaces thereof to the bottom of the compartment.

Gaskets having a portion thereof extending through the central aperture of the closure and covering an annular portion of the surface surrounding the aperture serve another very practical purpose apart from the humidifying aspect of the invention. When the cakes are removed from spinning machines and the machines are prepared for another spinning operation, certain parts including the spinning funnel must be removed before the cake may be removed, and then replaced before starting the spinning machine. As this work is done very hurriedly, many spinning funnels, which are ordinarily of glass, are damaged by chipping the end of the tube forming the lower part of the funnel, as the funnels are dropped into place. A rough or jagged edge at the end of the tube results in damage to the filament or the discarding of the funnel. A gasket of such thickness as to provide efficient fluid evaporation has the thickness and resiliency of a cushion which prevents damage to a spinning funnel tube when the funnelis dropped into its operating position.

Another practical expedient for carrying out the invention is illustrated in Figure 5. In this embodiment the compartment lid I20 is not provided with absorbent gaskets as in previous embodiments shown. Instead, the compartment walls may serve as support for the absorbent material used to promote liquid evaporation. In Figure 5, a wick or gasket is shown suspended on the under surface of the top wall of the compartment about the aperture provided for the lid We, The wick 10 is preferably supported by a. non-corrosive metal screen 12 and fastenings such as the small bolts 13. A groove 14 is provided in the upper surface of the top wall substantially over all parts of the wick 10 for distribution of water or other liquid. Fine-bore holes 15 conduct the water into the wick Ill. The flow of water to the wick is controlled by the size and number of the holes. As the groove 14 is wide and may tend to collect unwanted material which would clog the holes 15, a shield such as the plate 11 may be provided and held in placeby the bolts 73. Water is supplied to the groove from a water line 18 projecting into the hole 19. Salting out and crystallization of materials contained in liquors carried into the spinning bucket compartment by the yarn being collected, occurs most readily along surfaces against which such liquors are thrown from the spinning bucket. Deposits of such materials are often formed which interfere with the rotation of the bucket. It is found that these deposits do not form where the liquor is thrown onto the surface of a saturated wick or gasket such as included in the above-described embodiments; instead, the liquor remains a liquid which drains off the gasket and drops or flows to a lower region in the spinning compartment. Accordingly, therefore, the invention may be modified in any manner necessary to provide wicks or gaskets along any interior surface of a spinning bucket compartment, and ducts therefor, for carrying liquid thereto.

While preferred embodiments have been shown, it is understood that changes and variations may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Iclaim:

1. A method of humidifying comprising supporting a liquid-storing absorbent material within a spinning bucket compartment, and conducting a volatile liquid to the absorbent material to wet its surface exposed to the compartment atmosphere.

2. A method of humidifying the atmosphere of a spinning compartment comprising supplying a liquid to a distributing duct therefor on the exterior of the compartment, supporting a liquid-storing absorbent material within the compartment, and conducting the liquid from the ducts to the absorbent material.

3. A method of humidifying a spinning bucket compartment having a closure therefor comprising supporting a liquid-storing absorbent material on the inner side of the closure, conducting a vaporizable liquid through the closure into the absorbent material to wet the surface thereof exposed to the compartment atmosphere, and maintaining the pressure within the compartment at a pressure not greater than that outside the compartment.

4. An apparatus for humidifying a spinning bucket compartment having a closure therefor comprising a liquid-storing and absorbing material supported inside of the closure, a duct on the. exterior of the closure, a liquid conducting means connecting the duct to a surface of the absorbent material, and a liquid supply means for the duct,

5. An apparatus for humidifying a spinning bucket compartment comprising a liquid storing absorbent material attached to an inner surface thereof, a liquid conducting means extending through a wall of the compartment to the absorbent material, and a liquid supply means for the conducting means.

6. An apparatus for humidifying a spinning bucket compartment comprising a liquid distributing duct arranged along an upper outer surface thereof, a liquid supply means for the duct, a liquid-storing and absorbing material supported inside the compartment, and liquid conducting means connecting the duct to a surface of the absorbent material.

I. An apparatus for humidifying a spinning bucket compartment comprising a liquid-storing and absorbing material supported inside the compartment, a liquid supply means, and a liquid distributing means for carrying liquid from the supply means to a plurality of points along a surface of the absorbent material.

8. An-apparatus for humidifying a compartment having a closure therefor of substantially horizontal upper surface, comprising liquid storing absorbent material attached to the interior side of the closure, duct means through the closure to the absorbent material, a duct on the exterior of the closure, and liquid supply means for the duct. 4

9. Apparatus for humidifying a spinning bucket compartment comprising a removable closure for the top portion of the compartment, a liquid absorbent material secured to its inner lower surface, a groove in the upper surface of the closure, small holes through the closure connecting the groove with the absorbent material, and liquid supply means for the groove.

10. An apparatus as in claim 7 wherein the compartment is connected with vacuum-producing means.

11. An apparatus for humidifying a spinning bucket compartment comprising a removable substantially flat closure for the top surface of the compartment, its seating surface with the surface of the compartment comprising an annular gasket of liquid absorbent material, a smaller diameter concentric gasket of liquid absorbent material attached to the lower side of the closure, a liquid conducting groove on the upper surface of the closure, ducts through the closure connecting the groove and the gaskets, and liquid supply means for the groove.

12. An apparatus for humidifying a spinning bucket compartment comprising a closure having a central passageway for the top surface of the compartment, its seating surface with the surface of the compartment at least partially comprising an annular gasket of liquid absorbent material, another gasket concentric therewith of smaller outside diameter secured to the lower side of the closure presenting a disc surface to the interior of the compartment except for a central apertured portion to accommodate the stem of a spinning funnel, said apertured portion extending upwardly through the passageway of the closure to overlap its upper horizontal surface adjacent the passageway, liquid conducting grooves on the upper surface of the closure, ducts through the closure between the grooves and the gaskets, and liquid supply means for the grooves.

13. An apparatus for humidifying a spinning bucket compartment comprising a closure for the top surface of the compartment, a gasket of liquid absorbent material secured to the lower side of the closure of outer diameter such that the periphery thereof constitutes at least partially the surface of contact of the closure with the compartment and the radially inner portions of the gasket provide evaporating surface for a volatile liquid, liquid conducting grooves on the upper surface of the closure, ducts through the closure connecting the grooves and the gasket, and liquid supply means for the grooves.

14. An apparatus for humidifying a spinning bucket compartment comprising a closure for the .top surface of the compartment having a central passageway, a gasket of liquid absorbent material secured to the lower side of the closure of outer diameter such that the periphery thereof constitutes at least a portion of the surface of contact of the closure with the compartment, said gasket covering the entire lower surface of the closure except for a central apertured portion of the gasket extending upwardly through the passageway of the closure, liquid conducting grooves on the upper surface of the closure,'ducts between the grooves and the gaskets, and iiquid supply means for the grooves.

15. An apparatus for humidifying a spinning bucket compartment comprising a closure for the top surface of the compartment, a gasket of liquid absorbent material secured to and substantially covering the lower side of the closure, liquid conducting means on the upper surface of the closure, ducts through the closure connecting the liquid conducting means and the gasket,

, and liquid supply means for the liquid conducting the liquid conducting means and the gaskets,

and liquid supply means for the conducting means.

HUGH D. HALEY.

REFERENCES CITED The following referencesare of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,042,529 Huttinger June 2, 1936 2,045,708 Harrison June 30, 1936 2,045,717 Mitchell June 30, 1936