US2748587A - Device for the wet treatment of artificial threads - Google Patents

Description

June 5, 1956 K. J. SCHULZE 2,748,587

DEVICE FOR THE WET TREATMENT OF ARTIFICIAL THREADS Filed April 15, 1951 FIG- 1 FIG- 2 FIG- 3 FIG 4 FIG. 5

FIG. 8

KURD J- SCHULZE INVENTOR.

BY Wmcflmw PM ATTORNEYS United States Patent i) DEVICE FOR THE WET TREATMENT OF ARTIFICIAL THREADS Kurd Jiirgen Schulze, Oberbruch, Germany, assignor, by mesne assignments, to American Enka Corporation, Enka, N. C., a corporation of Delaware Application April 13, 1951, Serial No. 220,769

Claims priority, application Germany April 17, 1950 2 Claims. (Cl. 68-205) This invention relates to a device for the wet treatment of artificial threads.

Interinclined pairs of rolls are frequently used in the production of artificial threads by a continuous process. Since it is essential to use a series of wash liquids in the after-treatment of threads, especially in the viscose process, it is difficult to construct pairs of rolls which ensure that the individual after-treating baths are meticulously separated from one another. The principle of separate indentation enables considerable improvements to be made since in this way it is possible to prevent the baths from being mixed on the rolls. It is only possible to work economically and without interruptions when the individual bath liquids are prevented from mixing on the after-treating rolls and when the quantity of washing liquid entrained by the running thread is kept as small as possible. Previous proposals did not give satisfactory results in the latter respect. According to the previous proposals too much of the bath liquid was entrained which caused the thread to slide unsteadily over the rolls so that the thread windings ran over one another which led to the threads becoming entangled and subsequently broken.

Extensive experiments have shown that this disadvantageous effect is due to the shape of the surface of the lower of the two interinclined rolls. When the surface of the lower roll is smooth or provided with capillary fiutings it forms too thick a film of liquid from which the ascending threads carry away too much liquid with them to the upper roll.

It is an object of this invention to provide apparatus which will overcome the above disadvantages.

Other and further objects of the present invention will become apparent from the following description and appended claims taken together with the accompanying drawings, in which:

Figs. 1 through 5 are end views of rolls having a surface configuration according to the present invention;

Fig. 6 is a perspective view of a portion of the surface of a roll according to the present invention;

Fig. 7 is an end view of two inclined rolls according to the present invention; and

Fig. 8 is a side elevation view of the rolls according to Fig. 7.

It has now been found to be of great advantage for uninterrupted working if the threads ascending from the lower to the upper roll have as thin as possible a liquid sheath since otherwise the individual turns of the thread spiral readily adhere together on contact which leads to breakage of the thread. It is also important that the thread passing from one after-treating station to another should have as thin as possible a liquid sheath in order to keep the circulating wash baths clean. Since the fresh supply of after-treating liquid takes place on the upper roll it is naturally also desirable that the threads should carry as small as possible a part of the bath back to the upper roll again since, if there is too great a circulation of after-treating liquids, the concentration and, in the case of hot bath liquids, the temperature also suffer too great a variation. If the threads have too thick a liquid sheath then the ascending threads become very unsteady due to the formation of a liquid seal between the threads and the upper roll, the surface tension forces of which tear individual capillary threads and produce a tangle.

The experiments also showed that the above-described disadvantages which result from a thick liquid sheath around the ascending turns of thread can be removed by coarse longitudinal fluting of the lower roll of the interinclined pairs of rolls. The longitudinal fluting must be of such a shape that it has a profile tapering outwardly at an acute angle. For example, all triangular profile shapes having straight, convex or concave, convergent side faces are suitable for the purpose. Truncated pyramidal profiles can also be used or profiles which taper to two or more tooth edges. Preferably the longitudinal profiles are such that they give a zigzag separated indentation at the segmental limits of the roll. A surface shaped in this way has a very small capacity for retaining liquid so that the threads can carry only very little bath liquid with them. The surface of contact of the roll with the thread is also reduced considerably. This causes the liquids to be sprayed oif vigorously. The liquids are not rejected from a single part only of the thread windings in a large quantity but the rejection of liquid is distributed over the whole sector of the roll. As a result of this arrangement the ascending thread carries down the whole quantity of liquid which is supplied afresh to the upper roll but so much of the bath liquid is sprayed off by the lower roll that the ascending thread only carries with it about a quarter to one-third of the quantity which it carried with it as it ran on to the lower roll. A particular embodiment of the present invention will now be specifically described.

In Figures 1 to 5 are illustrated terminal views of rollers, which are provided with grooves running parallel to the axis, or ledges running between these grooves, of approximately triangular cross-section in the sense of the invention. The grooves and ledges are shown on only a part of the cylinder circumference; they extend, however, over the entire circumference, as is also evident from Figures 7 and 8.

According to Figure l, the projecting parts of the roller surface designated by 1 having a triangular cross-section, which is delineated by straight lines. In Figure 2, the cross-section of the ledges 2 is delineated by convex lateral lines. According to Figure 3 the delineating lines of the ledges are concave. The cross-sections of the ledges 4 in Figure 4 exhibit two straight side lines and a blunt tip, and in Figure 5, the cross-sections of the ledges 5 are delineated by doubly concave lateral lines.

Figure 6 shows a section from the envelope of a lower roller, as it is used according to the invention for the Wet treatment of threads, whereby for example, a hollow cylinder serves, whose surface exhibits the longitudinal grooves according to the invention. The cylinder envelope is interrupted in a zigzag form at 6 and 7. This interruption extends over the entire circumference of the roller body or of the hollow cylinder, as is clearly shown in Figure 8. The zigzag shaped ends of the two roller parts 8 and 9 according to Figure 6 engage in each other, but nevertheless leave open a slit 10 through which the liquid flowing in the longitudinal grooves of the roller can flow 0E, without becoming mixed with the liquid of the adjacent roller section. Besides the interruption by the slit 10, the roller surface can, of course, exhibit still further similar interruptions, so that a treatment of the rayon threads with more than 2 different liquids without a mixing of the same on the roller surfaces is made possible.

Figure 7 shows diagrammatically a front view of a roller pair and Figure 8 is a corresponding side view. The upper roller 11 has a smooth surface; it is however, di vided by a zigzag shaped interruption into two parts, so

that the liquids introduced through the lines 12 and 13 cannot become mixed on the roller surface.

The axis of the lower roller 14 is oblique in relation to the axis of the roller 11. Consequently, in the rotation of the rollers the rayon thread 15 is led in a spiral shape, without special thread guide organs being necessary.

The roller 14 is likewise divided by a zigzag shaped interruption, so that between the two parts there is a siit it as is more clearly shown in Figure 6. In the sense of the invention, the lower roller is provided with grooves or projecting ledges running parallel to the a Is, through which the carrying along of larger liquid quantities by the thread 15 is avoided.

What i claim is:

l. A device for treatment of artificial threads with liquids which prevent the artificial threads from sticking to each other dui after treatment, comprising a it of cooperating upper and lower rolls having their es inclincd to each other for advancing a thread thereover in a spiral path, the lower of said rolls having a surface of two sections each section consisting of contiguous longitudinal iiutings extending radially outwardly, the surface of the tiutings converging at an acute angle at the outer fiX- trcrnity thereof, the fiutings in one section being offset to a position between the fiutings of the other section in a circumferential direction, the fiutings having tooth-like portions on the ends thereof which define a zigzag channel extending circumferentially around said lower roll, and means for introducing liquids to said upper roll.

2. A device as claimed in claim 1 in which the tooth-lilac portions of said fluted surface extending into said zigzag channel in one direction extend past the tooth-like portions extending into said channel in the opposite direction, whereby a continuous longitudinal support for threads is provided.

References Cited in the file of this patent UNITED STATES PATENTS 1,578,241 Johnson Mar. 23, 1926 1,960,743 Junkers May 29, 1934 2,002,994 Hartmann et al. May 28, 1935 2,020,057 Hartmann Nov. 5, 1935 2,259,202 Cooper Oct. 14, 1941 2,263,440 Hansen Nov. 18, 1941 2,294,902 Gram Sept. 8, 1942 2,356,026 Berry Aug. 15, 1944 2,416,533 Naumann Feb. 25, 1947 2,661,522 Lowe Dec. 8, 1953 FOREIGN PATENTS 217,892 Germany Jan. 15, l9l0

Claims (1)

1. A DEVICE FOR TREATING OF ARTIFICIAL THREADS WITH LIQUIDS WHICH PREVENT THE ARTIFICIAL THREADS FROM STICKING TO EACH OTHER DURING AFTER TREATMENT, COMPRISING A PAIR OF COOPERATING UPPER AND LOWER ROLLS HAVING THEIR AXES INCLINED TO EACH OTHER FOR ADVANCING A THREAD THEREOVER IN A SPIRAL PATH, THE LOWER OF SAID ROLLS HAVING A SURFACE OF TWO SECTIONS EACH SECTION CONSISTING OF CONTIGUOUS LONGITUDINAL FLUTINGS EXTENDING RADIALLY OUTWARDLY, THE SURFACE OF THE FLUTINGS CONVERGING AT AN ACUTE ANGLE AT THE OUTER EXTREMITY THEREOF, THE FLUTINGS IN ONE SECTION BEING OFFSET TO A POSITION BETWEEN THE FLUTINGS OF THE OUTER SECTION IN A CIRCUMFERENTIAL DIRECTION, THE FLUTINGS HAVING TOOTH-LIKE PORTIONS ON THE ENDS THEREOF WHICH DEFINE A ZIGZAG CHANNEL EXTENDING CIRCUMFERENTIALLY AROUND SAID LOWER ROLL, AND MEANS FOR INTRODUCING LIQUIDS TO SAID UPPER ROLL.

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