US1958670A - Method of spooling or reeling artificial silk - Google Patents

Description

May 15, 1934.

J. W. LUBBERHUIZEN ET AL METHOD OF SPOOLING 0R REELING ARTIFICIAL SILK Filed Nov. 10, 1932 I nWi Hem Lubberhuisen Hans /-\\wln chvenk .7): venfo rs new R TDKN CY Fatented May 15, 1934 PATENT OFFICE METHOD OF SPOOLING OR REELING ARTIFICIAL SILK Jan Willem Lubberhuizen and Hans Alwin Schrenk, Arnhem, Netherlands, assignors, by mesne assignments, to American Enka Corporation, Wilmington, Del., a corporation of Delaware Application November 10, 1932, Serial No. 641,986 In Germany November 14, 1931 3 Claims.

Our invention relates generally to the art of manufacturing artificial silk and is directed more specifically to a method of spooling or reeling artificial silk in a manner to greatly reduce the winding tension which is a concomitant of present methods.

It is well known that the tension conditions through which a freshly spun thread passes during the successive stages of coagulation and decomposition may greatly affect the physical properties of the thread, such as its tensile strength and elasticity in dry and wet condition, its afiinity for colors, lustre and the like. It is also well known that tension acting on the thread at certain places during the stretch spinning process will materially increase the moisture resistance, dependent upon the coagulation and decomposition condition of the thread at such places.

The desired tensile strength of the thread is achieved by a number of the stretch spinning methods but in doing so the tension with which the silk is wound on the spools becomes too great and in consequence the permeability to washing and bleaching fluids is too slight. On drying on 'i the spool the thread tends to shrink, as a result of which the tension in the inner layers of the fully wound spool still further increases, while the outer layers of the silk are capable of yielding to this shrinkage tendency during drying so that marked differences in the physical properties of the threads of the outer and inner layers of the spool make themselves manifest.

Moreover, in consequence of this great tension the thread forms a very hard layer on the spool and is stretched beyond the permissible maximum, the layers of thread being so tightly drawn into one another that subsequent unreeling, during spooling and like operations, is impossible. Breakage of capillary and even of entire threads is not infrequent so that the quality of the prodnot is materially deteriorated. The higher the original winding tension, the longer is that part of the thread which does not yield good silk.

It is therefore an essential of satisfactory operation, particularly in the case of artificial silk which must be stretched during its production, to reduce the winding tension on to the spinning spool proper. According to the method of our invention we accomplish this result, viz, the reduction of winding tension, by placing in advance of the winding spool a friction roll which acts with a gliding friction on the thread and is driven in the direction of the thread take-off, whereby a release of thread tension is effected before the winding takes place. The term fric- Fig. 1 illustrates, diagrammatically, portion of a an apparatus for practising the method of the invention.

Fig. 2 shows, on a larger scale, the friction rollers in plan View.

Fig. 3 is a side elevation of one friction roll shown in Fig. 2.

The rotating friction roll 1 which may have a peripheral speed of 100 meters, draws the thread with gliding friction from the nozzle 2 out of the spinning bath 3 and preferably over braking elements 4 and 5 such as friction rolls, guide rods or the like. The thread passes'from the roll 1 to the winding spool proper 6, which may have a peripheral speed of meters. in this manner, the friction roll 1 relieves the thread of a part of the very great tension which is present in advance of the roll 1, so that the Winding tension proper in the rear of the roll 1 and in advance of the Winding spool 6 is relatively slight.

The friction rollers may consist of various materials, such as glass, porcelain or ebonite. As an alternative the surface of the rollers may be coated with the said material. The coefficient of friction of the rollers may be changed by the surface being unpolishe'd, particularly in case the surface consists of glass or porcelain, or by roughening etc.

The modus operandi of the braking rods or friction rollers will be hereinafter explained with the aid of Fig. 2. The braking rods 5 may consist of glass or porcelain. The braking effect thereof can be modified in the well-known manner by a change of the angle at which the thread engages the rods.

As Fig. 3 shows, the friction rollers are double rollers, in one of the grooves 7 runs the thread 8 just spun, while in the other groove 9 rests a string 10 which is fastened at a fixed point 11 and kept stretched by an adjustable braking weight 12. Not only by a modification of the braking weight but also by a displacement of the friction rollers in respect to each other, viz, a modification of the wrapping angle, the braking effect acting on the thread can be varied.

In further explanation of our invention, reference may be made to the tension conditions prevailing in cable and belt drives, which find their analogy in the present case.

By operating In Fig. 1

S1 indicates the tension of the thread in front of the friction roll 1;

S2 indicates the tension of the thread in the rear of the friction roll 1;

e is the basis of the natural logarithmic table;

1 is the coefficient of friction between the thread and the friction roll.

d is the looping angle, measured as a circular are having the radius 1 cm.

, The tension conditions are then represented by the formula Even without modification of the special friction j, i. e. without modifying say the nature of the thread or of the surface of the friction roll, the total friction may be easily changed by merely properly selecting the looping angle d, so that it is possible to relatively adjust the two thread tensions S1 and S2 to every desired relationship; in other words S1 may be reduced any desired extent in relation to the tension S2.

We claim:-

1. The process of producing artificial silk which comprises extruding a filament and passing the same through a coagulating bath, conducting the filament continuously as it is passed from the bath to a collecting device for forming a package, and causing the filament as it is passed to the collecting device to be propelled by a godet with which it has a desired friction contact, and effecting a drag on the filament in advance of the godet to thereby cause sufiicient slippage of the filament with respect to the godet to compensate for the tension variations occurring throughout the path of travel of the filament from the point of application of the drag to the collecting device.

2. The process of producing artificial silk which comprises extruding a filament and passing the same through a coagulating bath, conducting the filament continuously as it is passed from the bath to a collecting device for forming a package, and causing the filament as it is passed to the collecting device to be propelled by a godet with which it has a desired friction contact, effecting a drag on the filament in advance of the godet to thereby cause sufficient slippage of the filament with respect to the godet to compensate for the tension variations occurring throughout the path of travel of the filament from the point of application of .the drag to the collecting device, and effecting a stretching of the filament, the stretching being effected principally at the point of application of the drag.

3. The process of producing artificial silk which comprises extruding a filament and pass ing the same through a coagulating bath, conducting the filament continuously as it is passed from the bath to a collecting device for forming a package, and causing the filament as it is passed to the collecting device to be propelled by a godet with which it has a desired friction contact, effecting a drag on the filament in advance of the godet, and effecting a reduced tension on the portion of the filament between the godet and the collecting device with respect to the tension on the portion of the filament be' tween the godet and the point of application of the drag, whereby to compensate for the tension variations occurring throughout the path of travel of the filament from the point of application of the drag to the collecting device. 7

JAN WILLEM LUBBERHUIZEN. HANS ALWIN SCHRENK.

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