US2553127A

US2553127A - Guiding of threads or filaments

Info

Publication number: US2553127A
Application number: US730000A
Authority: US
Inventors: Barker Sydney Warren
Original assignee: Lustrafil Ltd
Current assignee: Lustrafil Ltd
Priority date: 1939-02-24
Filing date: 1947-02-21
Publication date: 1951-05-15
Anticipated expiration: 1968-05-15
Also published as: DE897617C; GB608437A; CH263233A; FR850826A; BE471420A; GB509854A; ES176909A1

Description

May 15, 1951 s. w. BARKER GUIDING OF THREADS OR FILAMENTS Filed Feb. 21, 1947 INVENTOR. 5YnNaY WARREN BARKER treatments.

Patented May 15, 1951 UNITED STATES P GUIDING OF THREADS OR FILAMENTS Sydney Warren Barker, Colne, England, assignor to Lustrafil Limited, Nelson, England, a corporation of Great Britain Application February 21, 1947, Serial No. 730,000 In Great Britain February 23, 1946 3 Claims. 1

The present invention relates to improvements in devices for guiding threads or filaments and more specifically to improvements in continuous processes for the production and/or treatment of artificial threads.

In such processes it is known to conduct the thread in a series of helical loops round a pair of rollers rotating upon shafts Which are inclined to one another, one or both being positively driven. During its traverse of the pair of rollers the thread may be subjected to various successive treatments such as setting, washing, drying, bleaching and the like. The rollers may be cylindrical or may vary in diameter from section to section so that the peripheral velocity is accom modated to variations in the length of the thread as it is extended or contracted by the various In such prior apparatus, the rollers may thus be tapered in one direction or the other at different parts of their length, and the tapering may be smooth, giving a conical surface, or in stages, giving a stepped surface; but in such known apparatus, the tapering of the respectively corresponding parts of both rollers is always effected in the same way, so that the two rollers are similar.

We have observed that, in the operation of such prior apparatus, at those places Where the rollers are conical, the diameter of the rollers increasing as the thread advances, the distance between successive loops of thread becomes shorter and the loops tend to crowd together. Conversely at those places where the rollers are conical and the diameters decrease, the loops appear at greater distances apart. This .crowding or spreading of the loops leads to difiiculties, for the inclination of the rollers and the tension on the thread (which two factors determine the distance between successive loops) are selected to give such a distance between loops as is found by experience to result in smooth working of the process, and any variation from this optimum distance is usually undesirable.

According to the present invention the crowding and spreading of the loops at conical parts of the rollers may be largely avoided and become negligible in effect by employing a pair of dissimilar rollers, one of which is conical or frustoconical whilst in the other roller a corresponding change in diameter is made by a series of steps.

That is to say, the change in diameter of one roller for a given length of that roller is exactly the same as the change in diameter for the corresponding length of the other roller.

In the accompanying drawings, Figs. 1, 2 and 3 illustrate diagrammatically several forms of apparatus in which the present invention may be embodied.

It is convenient to refer to that surface Tof the step which carries the loop of thread as the tread, and to the more or less perpendicular portion R between one tread and the next as the riser.

The treads are of such depth (1. e. distance between risers) as each to accommodate a singlev loo or several loops of threadand to permit advancement or displacement of the thread laterally (i. e. in an axial direction) to occur freely, within predeterminable limits, along each tread surface in passing around the roller thus stepped as is clearly shown in the drawings. In and of itself, tapering certain parts of a roller by thus stepping its surface is not broadly new, of course; for, as already pointed out hereinabove, it has been proposed heretofore thus to taper corresponding parts of both rollers of a cooperating pair, as an alternative to having said parts of both rollers smoothly tapered (i. e. conical), the rollers of the pair being thus alike or similar. But by employing dissimilar rollers in accordance with the present invention, an entirely novel effect is produced as will now be pointed out in greater detail.

A normal and satisfactory correction of crowding or spreading of the loops is obtained by making the treads cylindrical and parallel to the shaft or axis of the roller. This is illustrated in Fig. 1, for example, where roller 5 is conical, while roller 0 is composed of coaxial cylindrical portions 7, 8 and Q, which provide the treads upon which thread It is carried. If a further correction is desired the tread may be inclined towards the shaft or axis of the roller so that the angle between tread and riser is diminished and a dogtooth form is given to the step, as illustrated in Fig. 2, where roller I I is shown composed of coaxial frusto-conical portions l2, l3 and E4. On the other hand, if for any reason a correction smaller than normal is desired, the tread may be inclined away from the shaft or axis so that the angle between tread and riser is increased. This embodiment of the invention is illustrated in Fig. 3, where roller [5 likewise consists of a series of coaxial frusto-conical sections it, I? and IS, the tread inclination being the reverse, however, of that in Fig. 2. The dog-tooth form of the invention shown in Fig. 2 is useful at the drying stage where the contraction of the thread as it dries is allowed for by a gradually diminishing diameter of the rollers. The upper only one of the pair of cooperating rollers is' accomplished in accordance with the present invention are to be sharply distinguished from the V-section grooves with which it has heretofore been proposed to provide both rollers of a cooperating pair in order to prevent lateral 'displacement or roaming of the thread in its traverse and to increase its grip on the rollers, both of which objectives are achieved because the thread lies in the base or vertex of the V and is thus confined and gripped thereby. Since the term steps is herein employed to provide such sharp distinction, it is accordingly to be understood as positively excluding such grooves from within its scope.

I claim:

1. Apparatus for the manufacture of artificial threads in. which the thread is conducted in a series of helical loops round a pair of mutually inclined rotating rollers, at least one of which is positively driven, said rollers being tapered for at least a portion of their length, corresponding portions of the pair of rollers being dissimilar in longitudinal section in that where one roller changes diameter smoothly over a given length, giving a frusto-conical shape to the roller at that portion of its length, the same change in diameter in the corresponding portion of equal length of the other roller is made in a series of steps.

2. Apparatus as claimed in claim 1 in which the treads of the steps are cylindrical and coaxial.

3. Apparatus as claimed in claim 1 in which the treads of the steps are frusto-conical and concentric with but inclined to the axis of rotation of the roller.

SYDNEY WARREN BARKER.

REFERENCES CITED The'following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re. 22,178 O-ppenlaender Sept. 15, 1942 1,882,612 Hufford Oct. 11, 1932 2,002,996 Hoefinghoff et al. May 28, 1935 2,020,057 Hartmann et a1 Nov. 5, 1935 2,410,419 Bellezza, Jr Nov. 5, 1946 FOREIGN PATENTS Number Country 7 Date 509,854 Great Britain July 24, 1939

Claims

1. APPARATUS FOR THE MANUFACTURE OF ARTIFICIAL THREADS IN WHICH THE THREAD IS CONDUCTED IN A SERIES OF HELICAL LOOPS ROUND A PAIR OF MUTUALLY INCLINED ROTATING ROLLERS, AT LEAST ONE OF WHICH IS POSITIVELY DRIVEN, SAID ROLLERS BEING TAPERED FOR AT LEAST A PORTION OF THEIR LENGTH, CORRESPONDING PORTIONS OF THE PAIR OF ROLLERS BEING DISSIMILAR IN LONGITUDINAL SECTION IN THAT WHERE ONE ROLLER CHANGES DIAMETER SMOOTHLY OVER A GIVEN LENGTH, GIVING A FRUSTO-CONICAL SHAPE TO THE ROLLER AT THAT PORTION OF ITS LENGTH, THE SAME CHANGE IN DIAMETER IN THE CORRESPONDING PORTION OF EQUAL LENGTH OF THE OTHER ROLLER IS MADE IN A SERIES OF STEPS.