US3643412A

US3643412A - Method and apparatus for the production of crimped yarns

Info

Publication number: US3643412A
Application number: US861309A
Authority: US
Inventors: Yutaka Maeda; Hiroshiro Kimura; Akio Koshimo; Nagamasa Kanzaki; Katsumi Yasuzuka; Yoshinobu Furukawa
Original assignee: Nippon Rayon Co Ltd
Current assignee: Nippon Rayon Co Ltd
Priority date: 1969-07-18
Filing date: 1969-09-26
Publication date: 1972-02-22
Anticipated expiration: 1989-02-22
Also published as: FR2051825A1; CH531583A; DE1946622A1; CH1473069A4; GB1268142A

Abstract

The production of crimped yarns in which at least two yarns are fed under tension to a common twisting zone, wherein the yarns are pretwisted together and heated so as to be under a plastic state at least in a part of the zone. The yarns are thereafter separated into individual yarns by being pulled apart in different directions and at the same speed. The twisted yarns are turned at the separating point in the same direction as that of the initial pretwisting while the separated yarns are also turned in the same direction as that of the initial pretwisting.

Description

ldttiite @tates 1951m Maetlla et all...

[151 maaalm 1 1Feh.22, 11972 [54] METHUD AND APPARATUfi WUHR THE PRUDUCTHUN UP 'CiltllF/llPlElIl YARNE S [72] Inventors: Yutallm Malaria, Fujiyoshida-shi; lllirosliiro Mimura; Altio lltoshimo, both of Uji-shi;

Nagamasa lllki, liyoto-fu; llfiatsumi Yasuzuira; Yoshinohu Furultawa, both of Ujishi, all of Japan Nippon ll iayon Company Limited, Uji-shi,

Japan 1221 Filed: liept. 2t), W11 i) |21| Appl. No.1 9561,3119

I73] Assignee:

[30] Foreign Application Priority Data June 18, 1969 Japan ..44/56831 [52] 1.1.8. (11. 057/3 1 HS, 57/77.4, 57/157 T8 [51] llnt. Cl ..1D02g 11/02 [58] Field 011 Search ..57/34 NS, 77.3, 77.4, 77.42, 57/1 7 5,. .7 M 1575134 B.

[56] References tlited UNITED STATES PATENTS 2,111,211 3/1938 Finlayson et al. ..57/77.3 X

Gilchrist et a1. ..57/157 Berger, Jr. ..57/34 Primary Examiner-Stanley N. Gllrea th Assistant Examiner-Wemer H. Schroeder At!0rneyPicrce, Scheffler & Parker 57 scr The production of crimped yarns in which at least two yarns are fed under tension to a common twisting zone, wherein the yarns are pretwisted together and heated so as to be under a plastic state at least in a part of the zone. The yarns are thereafter separated into individual yarns by being pulled apart in different directions and at. the same speed. The twisted yarns are turned at the separating point in the same direction as that of the initial pretwisting while the separated yarns are also turned in the same direction as that of the initial pretwisting.

11 Claims, 10 Drawing Figures PAIENIEmmzz I972 SHEET 5 [IF 5 METHOD AND APPARATUS FOII TlllllE FIKOD UCTIION OF ElltIlVllFlEllI ifAIthlS BACKGROUND OF THE INVENTION This invention relates to a method and apparatus for the production of crimped yarns.

As herein used, the term crimped yarns refers to yarns consisting of one or more endless filaments or fibers. The yam material of such yarn includes at least in part of synthetic thermoplastic materials especially polyamide, polyethylene terephthalate, polyacrylonitrile, polyolefine, and the like.

Apparatus and process for the crimping of textile yarns are known according to which at least two yarns are twisted together in a twisting zone while being subjected to heating so as to be under a plastic state at least in a part of the zone, and are then separated into individual yarns by being pulled apart in different directions and at the same speed.

When yarn is treated in this way, it has been observed that certain forces are often set up which overstress the yarn and cause it to break.

Still further it has been found that such disadvantageous forces are set up when the separating point fluctuates to and fro along the yarn running direction whereas the forces are not set up when the separating point is maintained constant during the operation. Such fluctuation will prevent a common twisting zone from maintaining a constant length thereof. This, in turn, prevents the yarns from being crimped uniformly.

OBJECT OF THE INVENTION The object of the present invention is to provide a method and an apparatus referred to at the beginning of which the breakage of the yarns during the operation can be avoided.

Another object of the present invention is to provide a method and apparatus of which the separating point is maintained constant during the operation.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is an elevational view of an embodiment of the apparatus according to the present invention in which both the feeding zone and initial twisting zone are not shown,

FIG. 2 is a side view of the apparatus shown in FIG. I, in which the drawoff roller is not shown,

FIG. 3 is a plan view of the stationary yarn guide employed in the apparatus shown in FIG. I,

FIG. l is a schematic representation of one form of the feeding zone and the twisting zone according to the present inventlon,

FIG. 5 is an elevational view of another embodiment of the apparatus according to the present invention, in which both the feeding zone and twisting zone are not shown,

FIG. 6 is a side view of the apparatus of FIG. 5,

FIG. 7 is an elevational view of a further embodiment of the apparatus according to the present invention in which both the feeding zone and twisting zone are not shown,

FIG. 8 is a side view of the apparatus shown in FIG. 7.

FIG. 9 is an elevational view of a still further embodiment of the apparatus according to the present invention in which the feeding zone and twisting zone are not shown.

FIG. III is a side view of the apparatus as shown in FIG. 9.

DETAILED DESCRIPTION OF THE METHOD AND APPARATUS The present method for solving the aforementioned problems is characterized mainly in that at least two yarns pretwisted together are turned at the separating point in the same direction as that of the initial pretwisting and then each of the separated yarns is turned in the same direction. Yarns pretwisted together in an S-direction should be turned at the separating point in a counterclockwise direction when viewed along the yarn running direction and then each of individual yarns separated therefrom should be turned in the same direction, whereas, yarns pretwisted together in a Z-direction LII should be turned at the separating point in a clockwise direction when viewed along the yarn running direction and then each of individual yarns separated therefrom should be turned in the same direction.

In a heretofore known method, for example, it has been ob served that the separating point is apt to fluctuate longitudinally as the yarns run. In synchronism with the fluctuation, certain forces are set up which overstress the yarns and cause the breakage of the yarns. The present invention therefore is directed to maintaining the separating point constant during the operation by turning both the twisted yarns and the separated yarns, i.e., by preventing the separating point from shifting toward the drawoff roller as the yarns run.

It has been observed in the known art that the crimped yarn has a torque which would cause the yarn to produce snarls along its length when the yarn is in a relaxed state and the yarn is likely to break when the yarn is retensioned. It is our belief that the turning at two points will cause the yarns to lose temporarily the disadvantageous torque between said two points.

A rotatable hollow spindle is found preferable for the purpose of turning the yarns, wherein the yarn is wrapped around a snubbing bar and passed through the hollow spindle.

A moving friction means is also found preferable for turning the yarn. In case such moving friction. means is used, the yarn can be treated under constant tension by a frictional force occurring between the surface of the moving friction means and the yarn running in frictional contact with the surface of the friction means. It is preferable that the surface of the moving friction means be made of a elastic material having a suitable hardness, for example, a shore hardness of from to 90, such as natural rubber, polyurethane, polybutadiene, polychloroprene, nitrilbutyl and the like, each of which should have good anti-abrasion properties.

In the present invention, yarns may be heated in the twisting zone and/or in the feeding zone so as to be in a plastic state at least in a part of the twisting zone.

As another important object of the present invention, we provide an apparatus in which at least two yarns are fed to a twisting zone, are pretwisted together, are heated so as to be in a plastic state at least in a part of the twisting zone, and are thereafter separated into individual yarns by being pulled apart in different directions and at the same speed, the improvement comprising a yarn turning means for turning the yarns pretwisted together in the same direction as that of the initial pretwisting and turning individual yarns after being separated in the same direction as that of the initial pretwistmg.

At least three rotatable hollow spindles may be used as a yarn turning means.

Also at least two moving friction means, such as, rotating discs, moving endless belts, and the like, may be used as a yarn turning means.

Still further, a rotatable ring may be advantageously used as the yarn turning means. The term ring herein used is to be understood as including a doughnut-shaped ring, a short tube, a disc having a hole at its center, and the like. The yarns pretwisted together are brought in contact with one side surface of the ring, are separated into individual yarns, and the individual separated yarns thereafter are brought in contact with opposite side surfaces of the ring, whereby the yarns twisted together are turned in the same direction as that of the initial pretwisting and the individual yarns are turned in the same direction as that of the initial pretwisting.

Referring now to drawings, one embodiment of the present invention is illustrated in FIGS. I to 3, in which a rotatable ring is provided as a yarn turning means. In FIGS. I and 2, both the feeding zone and the twisting zone are not shown and only an end section of a pretwisted yarn l is shown.

Yarns

2 and 3 to be crimped are fed by feeding means defined by pairs of rollers A and 5 (see FIG. 4) with a constant speed over freely

rotatable guide rollers

6a and 6b, to a twisting zone in which the yarns between points 9 and I0 (FIG. I and I) are twisted together and heated by heating appliance 6 for the purpose of heat setting the false twist thus produced. As will be seen from FIG. 2, the end section of the twisted yarn 1 runs over the front side surface and then through the center hole of the ring 15 to the back side surface in frictional contact with these surfaces along a selected length of the yarns, so that the twisted yarn 1 and separated

yarns

2 and 3 are turned by being brought into contact with the rotatable ring 15, for a purpose to be made clear.

Yarns

2 and 3 divergently separated at separating point are guided through a small hole 21 provided at the end of stationary yarn guide 14 (FIG. 3), the location of which is usually selected substantially on the center axis of the ring. The separated yarns run thereafter to drawoff rollers 11 and 12 over freely

rotatable guide rollers

7 and 8. It is noted that the ring 15 should be rotated in a counterclockwise direction when viewed from the front side of the ring in the instance where the pretwisted yarn has S-twist, whereas clockwise rotation should be applied to the ring in the instance where the pretwisted yarn has Z-twist as shown in FIG. 1. The ring 15 is rotatably supported by a stationary ring 16 having ball bearings 20. The core of the ring 15 is made of a magnetizable material and the surface of the ring is made of rubber. In parallel, coaxial, and spaced relation with the ring 15, there is provided a magnetic disc 19 (FIGZ mounted on a driven shaft 18, so that the ring may be rotated by a magnetic force of the magnetic disc.

Stationary yarn guide 14 is arranged so as to face the front side of the ring 15, and is screwed to an end of rod 17. The stationary yarn guide has a small hole 21 in a manner such that the hole is located substantially at the center of the ring 15.

Another embodiment illustrated in FIG. 5 and 6 differs from the above-described embodiment by the fact that the ring 15, yarn turning means, is replaced by two

rotating discs

22 and 23 mounted on a driven shaft 24. The end section of the pretwisted yarn l is brought into contact with the disc 22 and the separated

yarns

2 and 3 are brought into contact with the disc 23. The separated

yarns

2 and 3 run through hole 21 of the stationary yarn guide 14 to the drawoff rollers 11 and 12. In case the pretwisted yarn 1 has an S-twist, the

discs

22 and 23 should be rotated in a clockwise direction when viewed along the yarn running direction, whereas in the case where the twisted yarn has a Z-twist the discs rotate in a counterclockwise direction. At least the surfaces of the

discs

22 and 23 are made of rubber for providing a frictional surface which is effective to rotate the running yarn.

Still another embodiment illustrated in FIG. 7 and 8 differs from the aforementioned embodiments by the fact that the ring or discs are replaced by three rotatable hollow spindles all of which have similar snubbing bars at their top. The end section of the pretwisted yarn 1 passes through the first hollow spindle 25, being wrapped around the bar 26 for the purpose of being turned as the spindle rotates. Having been separated at the separating point 10 a short distance after the bar 26, the

yarns

2 and 3 then run respectively through the second

hollow spindles

27a and 27b after passing through the hole 21 of the stationary yarn guide 14, and over the freely rotatable guide rollers 7' and 8. The

yarns

2 and 3 after passing through the

spindles

27a and 27b and, being wrapped around the snubbing bars 28a and 28b respectively for the purpose similar to the twisted yarn are finally run to the drawoff rollers 11 and 12. All of the

spindles

25, 27a, and 27b should be rotated in the same directions depending upon the twist direction of the twisted yarn.

According to the embodiment shown in FIGS. 9 and 10, the operation is similar to that shown in FIGS. 5 and 6 but includes two

endless belts

29 and 30 spaced apart but parallel to each other which are used instead of the ring, discs or hollow spindles of the other embodiments. The pretwisted and heatset ply yarn 1 passes over the first upper endless belt 29 driven by pulleys 31 and 31' frictionally engaging therewith. The ply yarn then passes through an eye or guide 21 formed at the end of bar 14 mounted on a fixed part of the apparatus. The ply yarn, which in this instance is formed of two yarns, is divided or separated into two

yarns

2 and 3 at a position just slightly prior to the eye 21.

The two

yarns

2 and 3, now crimped, then pass respectively over the second endless belt 30 driven by

pulleys

32 and 32 frictionally engaging therewith and thence over

guide rollers

7 and 8 mounted on a fixed part of the apparatus.

The yarns then pass two pairs of feed or drawoff rollers 11 and 12 respectively and thence to the takeup bobbins not shown.

It will be readily found that the ring 15 of FIG. 1 may be provided with a gear concentric to the ring for driving the ring in mesh with any driving gear in a manner that will be apparent to those skilled in the art.

Still further it will be found that one or more hollow spindles may be used in combination with one or more moving friction means hereinabove mentioned in such a manner that for example the pretwisted yarn may pass through a hollow spindle and the separated yarns thereafter pass by the turning disc in frictional contact with peripheral edge of the disc.

From the foregoing description, it will be seen that we have conceived a method and apparatus useful in the crimping of the textile yarns by which we are able to separate two or more twisted yarns into individual yarns without breakage, and to maintain the separating point constant so that the length of the twisting zone can be maintained constant and yarns having uniform crimp characteristics can be effected at high speed. For example, the yarn can be treated at the speed of from 400 to 1,200 meters per minute by the use of the method of the present invention.

This invention is not to be confined to any strict conformity to the showing in the drawings but changes or modifications may be made therein so long as such changes or modifications mark no material departure from the spirit and scope of the appended claims.

1. A method for producing crimped yams composed at least in part of synthetic thermoplastic materials which comprises:

pretwisting at least two yarns into a multiply yarn,

heating the multiply yarn to render it partially plastic, turning the multiply yarn in the same direction as when pretwisting the at least two yarns,

separating the multiply yarn into the individual yarns at a separating point by drawing the individual yarns apart in different directions at the same speed, and

turning the individual separated yarns in the same direction as that of the initial pretwisting to form the multiply yarn.

2. A method as claimed in claim 1 wherein the said at least two yarns travel at a speed of from about 400 to 1,200 meters per minute.

3. Apparatus for producing crimped yarn composed at least in part of synthetic thermoplastic materials comprising,

means for pretwisting at least two yarns to form a multiply yarn,

means for heating the multiply yarn to render it partially plastic,

a first turning means for turning the multiply yarn in the same direction as that of the initial pretwist of the at least two yarns to form the multiply yarn,

means for drawing each individual yarn of the multiply yarn in different directions at the same speed, whereby the multiply yarn is separated into the individual yarns at a separation point,

second turning means for turning each of the separated yarns in the same direction as that of the initial pretwist of the at least two yarns to form the multiply yarn, said second turning means being located between the point of separation and the drawing means.

4. Apparatus as claimed in claim 3 wherein said first turning means comprises a rotatable hollow spindle provided with a snubbing bar across the axis thereof, the multiply yarn passing over said bar in winding relation therewith while passing through the hollow spindle so that the yarn is turned.

5. Apparatus as claimed in claim 3 wherein said first turning means includes a moving means having a friction surface which engages the multiply yarn so as to turn the multiply yarn.

6. Apparatus as claimed in claim wherein the friction surface is composed of a material selected from the group consisting of natural rubber, polyurethane, polybutadiene, polychloroprene, nitrilbutyl and mixtures thereof.

'7. Apparatus as claimed in claim 5 wherein the friction surface has a shore hardness of from about 70 to about 90.

8. Apparatus as claimed in claim 5 wherein said moving means comprises a moving endless belt having a friction surface.

9. Apparatus as claimed in claim 3 wherein said second turning means comprises at least two hollow spindles each including a snubbing bar across the axis thereof, the separated yarn passing over said bars in winding relation therewith while passing through the hollow spindle so that the separate yarns are turned.

Ml. Apparatus as claimed in claim 3 wherein said second turning means includes moving means having a friction surface which engages each of the separated yarns.

llll. Apparatus as claimed in claim 3 wherein said first turning means and said second turning means comprise a single rotatable annular ring, diametrically opposed surfaces thereof forming said first and second turning means respectively.

Claims

1. A method for producing crimped yarns composed at least in part of synthetic thermoplastic materials which comprises: pretwisting at least two yarns into a multiply yarn, heating the multiply yarn to render it partially plastic, turning the multiply yarn in the same direction as when pretwisting the at least two yarns, separating the multiply yarn into thE individual yarns at a separating point by drawing the individual yarns apart in different directions at the same speed, and turning the individual separated yarns in the same direction as that of the initial pretwisting to form the multiply yarn.

3. Apparatus for producing crimped yarn composed at least in part of synthetic thermoplastic materials comprising, means for pretwisting at least two yarns to form a multiply yarn, means for heating the multiply yarn to render it partially plastic, a first turning means for turning the multiply yarn in the same direction as that of the initial pretwist of the at least two yarns to form the multiply yarn, means for drawing each individual yarn of the multiply yarn in different directions at the same speed, whereby the multiply yarn is separated into the individual yarns at a separation point, second turning means for turning each of the separated yarns in the same direction as that of the initial pretwist of the at least two yarns to form the multiply yarn, said second turning means being located between the point of separation and the drawing means.

6. Apparatus as claimed in claim 5 wherein the friction surface is composed of a material selected from the group consisting of natural rubber, polyurethane, polybutadiene, polychloroprene, nitrilbutyl and mixtures thereof.

7. Apparatus as claimed in claim 5 wherein the friction surface has a shore hardness of from about 70 to about 90.

10. Apparatus as claimed in claim 3 wherein said second turning means includes moving means having a friction surface which engages each of the separated yarns.

11. Apparatus as claimed in claim 3 wherein said first turning means and said second turning means comprise a single rotatable annular ring, diametrically opposed surfaces thereof forming said first and second turning means respectively.