US3645080A

US3645080A - Apparatus and method for manufacturing a fluffy yarn

Info

Publication number: US3645080A
Application number: US878835A
Authority: US
Inventors: Seiichi Yamagata; Masaaki Sakai; Toshimoto Matsubara; Shigeji Yamashita
Original assignee: Toray Industries Inc
Current assignee: Toray Industries Inc
Priority date: 1968-11-26
Filing date: 1969-11-21
Publication date: 1972-02-29
Anticipated expiration: 1989-02-28
Also published as: GB1260550A; FR2024304A1

Abstract

An apparatus for manufacturing a fluffy yarn used in combination with a yarn-advancing mechanism and having one or more fluffraising members axially rotational in contact with a ballooning portion of the advancing yarn for partially and intermittently cutting fibrous materials composing the yarn. The fluff-raising member may be rotated positively.

Description

United States Patent Yamagata et a1.

[54] APPARATUS AND METHOD FOR MANUFACTURING FLUFFY YARN [72] Inventors: Seiichi Yamagata; Masaalii Sakai; Toshimoto Matsubara, all of Otsu-shi; Shigeii Yamashita, Koga-gun, all of Japan [731 Assignees Toray Industries, Inc., Tokyo, Japan [22] Filed: Nov. 21, 1969 [21] App]. No.: 878,835

301 Foreign Application Priority Data Nov. 26, 1968 Japan ..43/102555 July 5, 1969 Japan... ....44/632l6 Sept. 30, 1969 Japan ..44/92630 [52] US. Cl. ..57/34 R, 28/67 [51] lnt.C1. ..D02j 3/02 I [58] Field oi Search ..57/l 34, 77.3, 2,156,28/67,

[56] References Cited UNITED STATES PATENTS 2,077,079 4/1937 Taylor et1al.,..,... ..s7/2

[151 3,645,080 51 Feb. 29,1972

l-lalin Elvin et a1.

Mayner Tlamicha Tlamicha McIntosh et a1. ..28/67 FOREIGN PATENTS OR APPLlCATlONS 604,708 5/1926 France ..28/67 Primary Examiner-Donald E. Watkins Attorney-Robert E. Burns and Emmanuel J. Lobato [571 I ABSTRACT An apparatus for manufacturing a fluffy yam used in combination with a yarn-advancing mechanism and having one or more fluff-raising members axially rotational in contact with a ballooning portion of the advancing yarn for partially and intermittently cutting fibrous materials composing the yarn. The fluff-raising member may be rotated positively.

23 Claims, 15 Drawing Figures Patented Feb. 29; 1972 4 Sheets-She 1 Patented Feb. 29, 1972 4 Sheets-Sheet 2 APFARATUS AND METTIGD FOR MANUFACTURING A FLTJFIFY YARN The present invention relates to an improved apparatus for manufacturing a yarn of a spun yarnlilte appearance from a multifilament yarn, more particularly relates to an apparatus for manufacturing a yarn of a spun yarnlike appearance by causing a ballooning multifilament yarn to contact a rotatable cutter for intermittently cutting individual filaments composing the yarn.

The term ballooning" as herein used implies all types of ballooning of an advancing yarn on a textile machine such as a ring twister, a double twister or a false-twisting spindle.

Various attempts have been proposed as to the manufacturing of a fluff yarn having a desirable appearance. One of the attempts utilizes ballooning action of the processing yarn. This method is carried out, for example, by encircling the ballooning portion of the processing yarn by a centrally bored cylindrical member having a raised inside peripheral surface capable of partially cutting fibers composing the processing yarn, by using a stationary, sharp, razorlike blade operable upon the ballooning portion of the processing yarn or by using a stationary bar of a roughened surface also operable on the ballooning portion of the processing yarn.

ln:any of the aforementioned method, however, a tension variation of the yarn in a ballooning condition or variation in the ballooningstatus of the yarn tends to cause variation in fluff formation and yarn breakage during the processing. Besides, wearing out of the cutter blade or smoothing of the roughened surface of the rod makes it difficult to uniformly manufacture the fluffy yarn for a long period. When two or more spindles of yarns are processes together, there tends to be created a variation from spindle to spindle in the fluff-forming effect and this forms a bar to the quick introduction of the conventional fluffy yarn manufacturing technique into the actual mass production systems.

A-principal object of the present invention is to provide an improved and practically useful apparatus capable of easily manufacturing, on a commercial basis, a uniformly fluffy yarn of a spun yarnlike appearance effectively eliminating drawbacks encountered in the conventional arts.

In order to attain this object, the apparatus of the present invention is provided with a rotational fluff-raising member pivoted in an arrangement capable of contacting the ballooning portion of the processing yarn and is advantageously usa ble for twisting equipment such as a ring twister or a double twister and for false twisting equipment having a false-twisting spindle. Especially, by rendering the fluff-raising member operative on the processing yarn during twisting, undesirable escape of the filaments due to cutting can effectively be obviated. This simultaneous application of the fluff-raising operation with the twist impartation further provides two advantageous merits, the first merit being, due to the fiber migration effect during the twist impartation, cut filaments are deeply contained into the yarn configuratioh and the surface of the yarn can be covered with fluffs of moderate length and the second merit being, because the componental filaments perform a rotation around the yarn axis during the twisting operation, the filament cutting can be uniformly accomplished over the entire yarn peripheral surface.

As to the aforementioned fluff raising member, various shapes and materials are available. It may be in the form of a member having a surface provided with abrasives such as granules, a cylindrical member having a cutter blade or blades or a rodlike member of a similar nature. The surface may be of a flat nature or a threadedly roughened nature. The roughness of the yarn contacting surface may be made by sandpaper, needle wires or grindstones. The rotation of the fluff-raising member around its rotational surface can be by a positive drive or by a frictional contact with the processing yarn in a ballooning condition. Research by the inventors of the present invention has confirmed that utilization of the false spindle mechanism is desirable in manufacture of the high-quality yarn at high production efficiency. As to this fact, further detailed discussion will be hereinafter presented.

The apparatus of the present invention is favorably and advantageously applicable for continuous multifilament yarns of natural, regenerated or synthetic fibers. The multifilament yarn may be provided with crimps imparted thereto in the preceding process or may be a mixture of filaments of a different cross-sectional characteristics, different fineness, different kinds or different physical properties. The multifilament yarn may be composed of so-called composite filaments.

Further features and advantages of the present invention will be more apparent from the ensuing description with reference to the accompanying drawings, wherein;

FIG. I is a schematic side view of a double-twister-type fluffy yarn manufacturing apparatus of the present invention,

FIG. 2 is a partly sectional plan view of a fluff-raising member usable for the apparatus shown in FIG. ll,

FIG. 3 is an explanatory view analytical of the force applied to the fluff-raising member shown in FIG. 2,

' FIG. 4 is an explanatory view analytical of the force applied to the yarn processed through the apparatus shown in FIG. I in a ballooning condition,

FIG. 5 is a schematic side view of an embodiment of the fluffy yarn manufacturing apparatus of the present invention having a fluff-raising member of a positive-drive-type and being a modification of the embodiment shown in FIG. 1,

FIG. 6 is a schematic side view of a modification of the apparatus shown in FIG. 5, wherein a jet-air ejection is used for the positive drive,

FIG. 7 is a schematic side view of a ring-twister-type fluffy yarn manufacturing apparatus and being a modification of the apparatus shown in FIG. 1, wherein the fluff-raising member is positively driven utilizing the jet-air ejection,

FIG. 8 is a schematic side view of still another embodiment, a false spindle type, of the fluffy yarn manufacturing apparatus of the present invention,

FIGS. 9, MB, llll, I2, 13 and M are explanatory drawings for showing relationship between the processing yarns and the various type fluff-raising members on the fluffy yarn manufacturing apparatus of the present invention, respectively,

FIG. MA is an explanatory drawing, seen in the advancing direction of the processing yarn, for showing a locational relationship between the fluff-raising member, the false-twisting spindle and the processing yarn on the apparatus shown in FIG. lltlB.

For the convenience in the development of the following discussion, the fluffy yarn manufacturing apparatus of the invention utilizing the twisting equipment will be dealt with first in the following description.

In the arrangement shown in FIG. 1, a fluff-raising member 4 is located upstream of a snail guide 5 in a rotational condition around its supporting axis and contactable with a yarn delivered from a spindle disc ll of a double twister mechanism. The yarn delivered from the spindle disc 1 forms a balloon 2 due to rotation of the spindle disc ll. The fluff-raising member 45 is so arranged that its rotational axis crosses the central axis of the balloon 2 at a selected angle 6 other than a right angle. The ballooning condition of the yarn is stabilized by the presence of a balloon control ring 3 located slightly upstream of the fluff-raising member 4. The ballooning yarn rotates around the central axis of the balloon 2 at a high speed and contacts the surface of the fluff-raising member 4. Then the filaments composing the yarn are partially and intermittently cut due to this contact and the fluff-raising member 4 also axially rotates due to this frictional contact with the downstreamly, that is, towards the snail guide 5 and a feed roller 6, advancing yarn. Thusly fluff-raised yarn is wound upon a package 7b rotating due to a frictional contact with a takeup drum 7a.

The mechanical design of the fluff-raising member 4 is shown in FIG. 2 in detail. Both ends of the fluH-raising member 4 are supported by a pair of chucks 8 having respective bearings 9 in an axially rotational arrangement. The bearings 9 are so supported by a supporter It) that the rotational axis of the fluff-raising member 4 crosses the central axis of the balloon 2 at a selected angle 0. Because of this particular angular disposition of the fluff-raising member 4 with respect to the yarn path, the contact of the yarn with the fluffraising member 4 takes place over the entire peripheral surface of the latter and, owing to this distribution of the contacting point, the locational wearing out of the contacting surface can effectively be mitigated and the fluff-raising member 4 is then capable of withstanding relatively long periods of use even under severe operational conditions. Further, thusly caused rotation of the fluff-raising member 4 creates the removal of foreign matter such as fluffs or other adhesive fibrous substances from the yarn contacting surface due to a centrifugal force and therefore, undesirable smoothing of the contacting surface can advantageously be obviated. Moreover, the discand bar-shaped fluff-raising members are usually cheaper in manufacturing cost than the cylindrical ones or other-shaped ones and the maintenance thereof is also easier than other types.

Next, the fluff-raising action on the yarn by the fluff-raising member of the present invention will be explained in more detail with reference to FIG. 3, wherein the rotational axis X-X of the fluff-raising member is supposed to cross the central axis YY of the yarn balloons at a selected angle which is other than a right angle. Provided that a force, at a cross point 0, for effecting the yarn ballooning around the central axis YY is F, the force T for effecting the axial rotation of the fluff-raising member is given by F sin 0. By adequately selecting the value of angle 0, various rotation speeds can be imparted to the fluff-raising member as long as the fluff-raising member is supported in an arrangement smoothly rotatable around its longitudinal axis.

The mode of the fluff-raising action performed by thusly caused rotation of the fluff-raising member is illustrated in more detail in FIG. 4. As is shown in the drawing, this fluffraising action is two-directional, that is, one is a fluff-raising force 11a mainly perpendicular to the yarn axis and the other is a fluff-raising force 11b mainly parallel to the yarn axis. Because these two fluff-raising forces are applied simultaneously, instantaneously and intermittently to the yarn, fluffraising of the yarn can be carried out in a stable operational condition, unfavorable smoothing of the yam-contacting surface can effectively be mitigated due to the aforementioned speedy rotation of the fluff-raising member and variation in the surface condition of the fluff-raising member can be compensated for by the aforementioned distribution of the yarn contacting point over all the surface area. Thus, even the unevenness in the yam-contacting surface has no direct unfavorable effect on the fluffy yarn produced.

Further, according to the experimental results obtained by the inventors of the present invention, the fluff-raising member may be located any place if it is within the ballooning zone of the yarn. ln this connection, however, in the case of the ring twister, it is desirable to locate the fluff-raising member as close to the traveller, that is, a location of the maximum ballooning diameter, as possible. This is because of the relatively large magnitude of the centrifugal force acting upon the yarn at the referred location. Needless to say, in the case of the fluff-raising member of the positive drive type, it is advantageous to rotate the fluff-raising member in a direction opposite to the advancing direction of the processing yarn. By thusly selecting the rotational direction, a remarkable filament cutting effect can be acquired.

The following example is illustrative of the aforementioned embodiment of the fluffy yarn manufacturing apparatus of the present invention.

EXAMPLE 1 The arrangement shown in H6. 1 was designed for a double twister of a conventional type, the angle 0 being 45. The fluffraising member was bar shaped having a round cross section and was made of steel. A polyester multifilament yarn of 100 denier thickness containing 48 filaments was processed for flufi-raising. The yarn contacting surface of the fluff-raising member was covered with hard grannules of 300 grading Rotational spindle speed Number of twists imparted 8,000 r.p.m.

B00 TPM The resultant rotational speed of the fluff-raising member was approximately 3,000 rpm. and the acquired fluffy yarn was provided with approximately 850 fluffs per meter length. No smoothing and wearing out of the yam-contacting surface were observed and the number of formed fluffs per unit yarn length at various states of the yarn processing, which is presented in the weight in grams of the taken-up yarn package, was as is illustrated in Table l for the system of the present invention and for the conventional system. ln the case of the conventional system, the fluff-raising member was disposed in a stationary arrangement, that is, not an axially rotational arrangement.

As a result of this experiment, the following remarkable information could be acquired. That is, using the apparatus of the present invention, the variation in the yarn tension, namely variation in the balloon shape, can be absorbed by the apparatus always obtaining formation of fluffs of approximately a constant number per unit yarn length. The reason for this is that, when the contacting pressure between the yarn and the surface of the fluff-raising member increases, the fluff-raising member starts to rotate at a higher speed for lowering the formation of the fluffs while, when the contacting pressure decreases, the fluff-raising member tends to decrease its rotational speed for activating the formation of the fluffs.

As is already mentioned regarding the foregoing embodiment, the fluff-raising member is rotated around its supporting axis owing to contact with the ballooning yarn. In this contacting mechanism, however, the frequent displacement of the contacting point of the yarn with the surface of the fluff-raising member is apt to cause irregular rotation of the fluff-raising member. This irregularity in the rotation of the fluff-raising member is rather preferable when a fluffy yarn having an irregular ornamental appearance is required in manufacturing. However, in case a fluffy yarn having a uniform ornamental appearance is required in manufacturing, it is necessary to avoid the aforementioned disturbance in the rotational condition of the fluff-raising member. In order to obviate this undesirable disturbance on the rotational condition of the fluffraising member, it is advantageous to positively rotate the fluff-raising member so as to acquire a uniform fluff-raising effect throughout the operation. Realization of such a uniform fluff-raising action enables the apparatus to be further advantageously employed in an actual mass production system on a large commercial basis.

The embodiment shown in FIG. 5 is one of the examples of the aforementioned positive-drive-type arrangement used for a conventional double twister, wherein the fluff-raising member is positively rotated at high speed owing to a frictional contact with the processing yarn at a position beyond the termination of the yarn ballooning. in this arrangement, the nonballooning portion of the advancing yarn positively rotates the fluff-raising member at a rotational speed or in a rotational direction different from those of the rotational speeds of the ballooning yarn portion. In the example shown in the drawing, the advancing yarn is engaged with a pulley secured to an end of the fluff-raising member for rotating the latterpositively. The fluff-raising member may be of a cylindrical, conical or cone drum shape and its lateral cross-sectional profile may be round, polygonal, gear-toothed or elliptical. The double twister used in the example shown in the drawing is the same as that used for the embodiment shown in FIG. 1 and the same reference numerals are used for common elements. In the illustrated embodiment, the yarn delivered from the spindle disc 1 is advanced towards the snail guide 5 forming the balloon 2 whose rotational mode is stabilized by the presence 'of the balloon control ring 3. On the path between the snail guide 5 and the balloon control ring 3, the yarn contacts the fluff-raising member 4 at a high advancing speed for raising the fluff. Then, the yarn contacts a pulley 12 secured to one end of the fluff-raising member after passing over a guide roller located in between the snail guide 5 and the pulley l2. Owing to this frictional contact of the advancing yarn with the pulley 12, the pulley 12, that is, the fluff-raising member 4, is axially rotated for effecting the fluff-raising action on the ballooning yarn. Next, the yarn is wound up onto the package 7b rotating through contact with the takeup drum 7a. The positive rotation of the fluff-raising member is most simply realized by utilizing the frictional contact with the advancing yarn as in the case of the present embodiment. However, it can. also be performed by driving the flutT-raising member through a belt drive connection with the rotational shaft of the feed roller 6 or the takeup drum 7a. By thusly employing a positive drive of the fluff-raising member, the rotational condition of the fluff-raising member is remarkably stabilized, malfunctions caused by irregular rotation of the fluffraising member can be effectively mitigated and a uniform flufflraising effect with a high production efficiency can result when compared with the foregoing embodiment of a negative drive type.

The following examples are illustrative of the aforementioned positive-drive-type apparatus of the present invention.

EXAMPLE 2 A polyester multifilarnent yarn of 100 denier thickness and containing 48 filaments was processed through the apparatus shown in FIG. 5. The rotational speed of the spindle was 8,000 rpm. and the number of twists imparted to the yarn was 650 TPM. The fluff-raising member, which was bar shaped having a round cross section of 5 mm. diameter, was provided with a yarn-contacting surface covered with diamond granules of 300 grading (Korngrosse). The fluff-raising member was arranged in such a manner that the ballooning yarn contacted the yam-contacting surface for a length of 35 mm. In the manner shown in FIG. 5, the fluff-raising member was rotated in a direction opposite to the advancing direction of the yarn at a rotational speed of about 150 rpm. Even after long periods of use, neither smoothing nor wearing out of the yarncontacting surface was observed and the resultant yarn of a very spun-yarn-like appearance was provided with fluffs whose number was approximately 750 per meter. Handling quality was also very favorable.

EXAMPLE 3 The type of processing yarn and processing condition were the same with those in the foregoing example with the only exception that the positive drive arrangement was modified from that shown in FIG. 5. In the present arrangement, the fluffraising member 4 was rotated, by connecting a pulley 12 secured to one end of the fluff-raising member 4 to a rotational shaft of the feed roller 6 by a belt drive, in an advancing direction of the yarn at a rotational speed of 1,500 r.p.m. The

resultant fluffy yarn of a very spun-yarn-like appearance was provided with fluffs whose number was about 820 per meter.

A further modification of the embodiment shown in FIG. 5

is shown in FIG. 6, wherein a pneumatic system is adopted for effecting the positive drive of the fluff-raising member 4. This application of the pneumatic flow also brings about a cleaning effect to the fluffraising member and its related machine parts. In the drawing, the same reference numerals are used for elements which are common with those used in the embodiments shown in FIG. 5. The fluff-raising member 4 of this embodiment is provided with several vanes or wings l3 radially secured to one end thereof and a compressed air-jet is ejected against the wings 13 from a nozzle 14 disposed in the vicinity of the radially winged end of the fluff-raising member 4 in an arrangement connected to a suitable pneumatic source (not shown). By this ejection of the compressed air-jet flow, the wings 13, that is, the fluff-raising member 4, is rotated at a high rotational speed. Usually, an air-jet flow of l kg./cm. pressure is sufficient for causing the high-speed rotation of the practically usable-type fluff-raising member with an effective cleaning effect on the fluff-raising member and its related machine parts. An effective obviation of the malfunction of the apparatus can be assured by the application of the aforementioned pneumatic system.

In the embodiment shown in FIG. 7, the apparatus of the present invention employing the above-described positive drive arrangement is applied to a conventional-type ring twister. In this ring twister, a yarn l6, delivered from a stationary package 15, is supplied to the system at a constant supply speed by a pair of delivery rollers 17a and 17b. Then, the yarn 16 is advanced, forming a balloon, towards a bobbin 21 passing through a guide bar 18, snail guide 19 and a traveller- 20 travelling along a ring rail. In combination with the above-listed elements, a rotational spindle member 24 is mounted on a ring frame 22 of the twister. The spindle 23 is further provided with radial wings 25 facing a pneumatic nozzle 26 located in the vicinity of the spindle 23 and ejection of a compressedalr-jet flow from the nozzle 26 causes rotation of the spindle, that is, the fluff-raising member 24, at a high rotational speed. Because the disc-shaped fluff-raising member 24 is so located so as to be capable of contacting the ballooning portions of the advancing yarn at its roughened fringe, fluffs are formed on the yarn processed.

The following examples are illustrative of the abovedescribed apparatus of the present invention.

EXAMPLE 4 A polyester continuous multifilament yarn of denier thickness containing 48 filaments was processed through the apparatus shown in FIG. 7. The rotational speed of the spindle was 5,000 rpm. and the number of Z twists imparted to the yarn was of 700 TPM.

The surface of the hair raising disc was covered with diamond granules of 300 grading and the disc was rotated in a direction opposite to the ballooning direction of the yarn at a rotational speed of 500 rpm. by ejection of the jet-air flow against the radial wings 25 from the pneumatic nozzle 26. The distance between the snail guide 19 and the ring rail was constantly maintained. After long time processing of the yarn, neither smoothing nor wearing out of the roughened surface of the disc was observed and the resultant fluffy yarn of a spun yarnlike appearance and handling quality was provided with about 700 fluffs per meter of yarn length. The processing condition was essentially stable throughout the entire operation.

EXAMPLE 5.

A polyester continuous plied multifilament yarn of 2/150 denier thickness each containing 48 filaments was processed through the apparatus the same as that used in the preceding example. In this case, the fluff-raising operation was carried out simultaneously with plying wooly textured yarns of 420 primary Z twists per meter of yarn length. The rotational speed of the spindle was 6,000 rpm. and the member of S secondary twists was 390 TPM. The surface of the fluff-raising disc was covered with diamond granules of 250 grading. By the ejection of the air-jet flow of about 1 kg./cm. pressure against the radial wings 25, the disc was rotated in a direction opposite to the rotational direction of the spindle 23 at a rotational speed of about 2,000 rpm. The distance between the snail guide 19 and the ring rail level was constantly main- Inlnni Arno tained. Even after a long period of yarn processing neither smoothing nor wearing of the disc surface was observed and the fluff-raising disc and its related machine parts were kept clean throughout the operation. The resultant yarn was provided with very fine and uniform fluffs whose number was about 750 per meter of yarn length and a very worsted yarnlike appearance and handling quality.

EXAMPLE 6.

A nylon continuous multifilament yarn of 140 denier thickness containing 48 filaments was processed through the apparatus the same with that used in Example 4. The rotational speed of the spindle was 8,000 r.p.m. and the number of imparted S twists was 600 TPM. The disc surface was covered with an abrasive paper of 240 grading and the fluff-raising disc was rotated at a rotational speed of approximately 6,000 r.p.m. by an ejection of an air-jet flow of about 0.6 kg./cm pressure. The fluff-raising operation could be carried out in a very desirable condition as in the case of the preceding example and the resultant yarn was provided with about 680 fluffs per meter of yarn length. The handling quality and appearance of the resultant fiuffy yarn was very much like a cotton spun yarn. No malfunctions of the apparatus were experienced throughout the operation. The production efficiency was kept high through use of the apparatus of the present invention.

As was already stated in the opening part of this specification, the repeated experimental results obtained by the inventors of the present invention have confirmed that the falsetwisting spindle mechanisms should advantageously be used in the case when a remarkably high rate production is required or when a multifilament flufly yarn of a finer thickness is required to be manufactured without the lowering of tensile property. In this case, the fluffy yarn manufacturing system should be composed of a spindle mechanism capable of ballooning the processed yarn substantially without impartation of twists to the yarn and a rotational fluff-raising member contactable with the ballooning yarn. The fluff-raising member should be rotationally supported by an axial support and be rotated due to a ballooning tension and a frictional contact of the yarn. Fluffs are formed by partly cutting the filaments composing the processed yarn by the cutting action of the filament cutter disposed to the external surface of the fluff-raising member. The fluff-raising member should be disposed in an arrangement capable of having various angular relationship with respect to the rotational axis of the spindle. In order to provide the yarn with a stable ballooning condition and to have the yarn contact the fluff-raising member at a high advancing speed, a longitudinally bored-type false-twisting spindle having an eccentrically drilled yarn guide hole is used in this system for impartation of no twists to the processed yarn. By using a thusly designed false-twisting spindle, it is possible to advance the yarn at a high speed with the ballooning tension of an increased magnitude. Therefore, a remarkably stable and uniform fluff-raising effect can accordingly result. Further, the rotational arrangement of the fluff-raising member is very effective in absorbing the variation in the yarn speed due to variation in the ballooning condition. This variation absorptiveness assures further excellent filament cutting action. In case the aforementioned longitudinally bored-type false-twisting spindle is adopted in the system, a favorable and stable fluff-raising action can be acquired even without positively rotating the fluff-raising member. Namely, even when the fluff-raising member is disposed in an angular arrangement perpendicular or parallel to the rotational axis of the spindle, the fluff-raising member can be sufficiently rotated due to an enlarged contacting pressure of the fluff-raising member with the processing yarn. However, no trouble will arise even when the fluff-raising member is positively rotated by a suitable driving means. In case the rotational axis is parallel to the spindles rotational axis, more than two fluff-raising members of different diameters can be used in combination. One such example is shown in FIG. 12, wherein three fluff-raising

members

39, 40 and 41 are disposed in combination. In this case, it is desirable that the surfaces of the combined fluff-raising members contact the ballooning portion of the yarn in a stepped relationship from each other and that the surfaces are parallel or inclined with respect to the ballooning line of the yarn. However, any modification of the above-described desirable arrangement is also employable. Because a number of fluff-raising members are used in combination in the above arrangement, the total fluff-forming effect can be well equalized for mitigation of the variation in the fluifforming effect from spindle to spindle and, further, by varying the grading of the fringe surfaces or shape of the fluff-raising members, various types of fluffy appearance of the yarn can be obtained as desired.

It is also possible, in the aforementioned arrangement, to provide the fluff-raising member with a jet-flow conduit radially extending from a vicinity of the rotational axis of the fluffraising member. With the high-speed rotation of the fluff-raising member, a pneumatic flow is spontaneously generated and flows radially towards the external surface of the fluff-raising member through the radial conduits. If necessary, the pneumatic radial flow can be generated by supplying the flow from a suitable external pneumatic source. By this radial ejection of the pneumatic flow, foreign matter such as oiling agents or fibrous gums can be removed from the yarn contacting surface.

Instead of the pneumatic flow ejection, it is also possible to utilize a pneumatic suction flow in the art of the present invention. Further, although the flow used is favorably an airflow, an aqueous flow can also be utilized in accordance with requirements in the actual production system.

The type of false-twisting spindle used in the present invention should be selected in conformity to the kind of yarn to be processed, type of processing system or mode of processing conditions. Among the various types of false twisting spindles, a longitudinally and eccentrically bored false-twisting spindle is usually used with preferable results. The false-twisting spindle of this design can result in an optimum ballooning condition of the yarn according to the kind of yarn to be processed and type or material of the fluff-raising member used. As to the dimensional features of the eccentric bore of the spindle of this type, the center of the bore should preferably be offset from the'center of the spindle from 2.5 to 510 mm. which corresponds to a balloon diameter from 5 to 10 mm. When the deviation exceeds 5 mm., a lowered running efficiency of the spindle will result. When the deviation is smaller than 2.5 mm., the contacting surface area of the fluff-raising member with the yarn will be narrowed resulting in lowered frictional effect of the surface on the yarn, that is, lowered fluff-raising effect of the system.

Referring to FIG. 8, an embodiment of the apparatus of the present invention combined with the false twisting spindle of the above-mentioned design is shown. In the illustrated embodiment, a continuous multifilament yarn delivered from a yarn package 27 is processed through a spindle 29 located in between a pair of spacedly

disposed feeding equipments

28 and 30. The spindle 29 is designed in a rotational arrangement and the offcenter advancement of the yarn is effected by a head portion 290 of the spindle 29 which is provided, for example, with an offcenter yarn guide bore. Because of this offcenter yarn guide bore, the yarn forms a balloon in a zone between the head portion 29a and an upstreamly located yarn guide 32. In contact with this ballooning portion of the processing yarn, a fiufi-raising member 31 is disposed in such a manner that the yarn contacts a fluff-raising element (for example, a roughened surface 31a in the embodiment shown in FIG. 9) disposed to the external surface of the fluff-raising member 31. Through the aforementioned contact of the yarn with the fluff-raising element, filaments contained within the yarn are partly cut and the yarn is wound up onto a package 34 The relative engagement of the yarn with the aforementioned offcenter false-twisting spindle 29 and the fluff-raising member 31 is shown in detail in FIG. 9. The fluff-raising member 31 is mounted on an axial support which is rotationally supported by a pair of

bearings

35a and 35b at its both ends. The processing yarn forms a balloon within a zone in between the yarn guide 32 and the head portion 29a of the offcentertype false-twisting spindle 29 and, in that ballooning condition, intermittently contacts the roughened surface 31a of the fluff-raising member 31 for formation of fluffs on the surface of the yarn. Together with this fluff-raising action, the fluff-raising member 31 is rotated at high speed due to the yarn ballooning tension and frictional contact with the advancing yarn.

In the arrangement shown in HO. 9, the fluff-raising member contacts the yarn at its surface perpendicular to the advancingdirection of the yarn for raising the fluffs and performs rotation in the advancing direction of the yarn. Therefore, the rotation of the fluff-raising member generates a centrifugal force with respect to the rotational axis of the fluffraising member. Owing to the thusly generated centrifugal force, fibrous gums or oiling agents sticking to the yarn contacting surface of the fluff-raising member is removed therefrom and possible smoothing or wearing out of the surface can be effectively mitigated. In addition to the abovedescribed merits, the rotational speed of the fluff-raising member 31 changes automatically in accordance with variation in the contacting pressure of the yarn with the fluff-raising member's surface and, owing to this rotational speed change, the fluff-raising action can always be preserved in a constant condition. When the contacting pressure of the yarn with the fluff-raising member is increased due to increase in the ballooning tension, the fluff-raising member rotates at relatively high rotational speed while, when the contacting pressure is minimized due to drop in the ballooning tension, the fluff-raising member rotates at a relatively low rotational speed. Therefore, the variation in the yarn ballooning tension can be automatically absorbed by the change in the rotational speed of the fluff-raising member for preservation of the contact fluffraising condition. Thusly, the time-functional variation in the fluff formation can be remarkably mitigated. Moreover, the shape of the yarn balloon can be constantly maintained throughout the fluff-raising operation due to the presence of the particularly designed head portion 29a of the offcentertype false-twisting spindle 29. All the above-described merits are very important key factors in the manufacture of a fluffy yarn of uniform quality.

The-locational relationship between the balloon of the. yarn and the fluff-raising member 31 is shown in FIGS. A and 108. In FIG. 10A, the yarn 36 advances, forming a balloon of R radius, perpendicularly to the drawing sheet surface from the viewers side to the back side of the sheet contacting the external surface of the fluff-raising member 31. In this arrangement, the axial direction YY of the fluff-raising member 31 supported by the

bearings

35a and 35b can be deviated to the direction Y'Y by an angle 6, for changing the contacting condition the yarn 36 with the yam-contacting surface of the fluff-raising member 31. Further, as is shown in FIG. 108, the axial direction YY of the fluff-raising member 31 can be deviated to the direction Y"Y" by an angle 6 for the same purpose. Especially, the latter change of the axial direction of the fluff-raising member is effective in positively changing the rotational speed of the fluff-raising member 31 through change in the frictional resistance.

In the embodiment shown in FIG. 11, a fluff-raising member 37 of a cone type is so disposed that the axial direction thereof is parallel to the rotational axis of the false twisting spindle and the fluff-raising member in this embodiment is rotated due to a frictional contact thereof with the ballooning yarn.

In the embodiment shown in FIG. 12, the yarn balloon is formed within a zone in between an offcenter yarn guide hole 29b formed through the head portion 29a of the false-twisting spindle 29 and a yarn guide 38 located upstream of the falsetwisting spindle 29. In connection with this balloon of the yarn 36, three

fluffraising discs

39, 40 and 41 having respective yam-contacting surfaces 390, 40a and 410 are mounted on a common rotational shaft with the aforementioned surface fluff-raising member Ill contacting the yarn balloon in a stepped condition. The common shaft supporting the fluff-raising discs is rotationally supported by the pair of

bearings

35a and 35b. In this embodiment, the three fluff-raising discs may be provided with different radii r r, and r different shapes, different materials or different surface treatments. By utilizing the combination of the above-described differences in the mechanical features of the fluff-raising discs, the variation in the fluff-raising action can be mitigated considerably.

Referring to FIGS. 13 and 14, embodiments of the apparatus of the present invention having flow conduits formed in the fluff-raising member are shown.

In the embodiment shown in FIG. 13, the two fluff-raising members are provided with

flow conduits

43 and 44 radially extending from their central axes and the fluff-raising members are rotated due to contact with the ballooning yarn 36 advancing downward in the drawing.

In the embodiment shown in FIG. 14,

flow conduits

45 and 46 are formed in such a manner that the flow is ejected toward the external yarncontacting surface 42a of the fluff-raising member 42 of upright and inverted type. By generation of the flow, foreign matter sticking to the yam-contacting surface 420 can be effectively removed therefrom. The flow to be ejected is not limited only to a pneumatic flow. Particularly in case when the surface is covered with such oily substances as fibrous gum, it is desirable to use an adequate solvent capable of solving such substances.

The following examples are illustrative of the aforementioned embodiments of the present invention.

EXAMPLE 7 A polyester multifilament yarn of 75 denier thickness containing 36 filaments was processed through the apparatus of the present invention shown in FIG. 8. The yarn was primarily twisted prior to being wound in package form and from the package 27, the yarn processed through the fluff-raising system of the present invention. The fluff-raising member shown in FIG. 9 was used and the whole external surface thereof was roughened. The processing conditions of the yarn were as follows.

Number of primary twists Roughening treatment about 3,500 r.p.m.

Spindle type Element 29 in FIG. 8 Rotational speed of the spindle 300 r.p.m. Maximum radius of the balloon 3 mm.

Yarn speed 200 MPM The resultant fluffy yarn was provided with uniformly raised fine numerous fluffs and enhanced quality when compared with the conventional spun yarn.

EXAMPLE 8 A polyester multifilament yarn of 50 denier thickness containing 24 filaments was processed through the apparatus of the present invention shown in FIG. 8. The fluff-raising member shown in FIG. 13 was used and an airflow was generated so as to flow toward the external surface of the fluffraising member. The external surface of the fluff-raising member was shaped in a balde-form made of hard material. The processing conditions were as follows.

Number of primary twists 650 TRM Rotational speed of the fluff-raising member about 4,000 TPM Spindle type Element 29 in FIG. 8 Rotational speed of the spindle 300 r.p.m. Maximum radius of the balloon 2.5 mm.

Yarn speed I20 MPM nun: Ann

The resultant fluff yarn was provided with extremely enhanced quality and good adaptability for use in the manufacturing of fabrics of a high grade.

What is claimed is:

1. An improved apparatus for manufacturing a fluffy yarn, comprising means for supplying a multifilament yarn, means for advancing said yarn from said supply, means for producing a balloon in said advancing yarn, means for stabilizing said balloon, means for taking up said yarn from said ballooning means and fluff-raising means disposed externally of said balloon in position to be intermittently contacted by said yarn in said balloon, said fluff-raising means comprising at least one rotatable fluff-raising member provided on its peripheral surface engageable by said ballooning yarn with cutting elements for severing filaments of said multifilament yarn through contact therewith to produce a fluff on said yarn.

2. An improved apparatus according to claim 1, in which said fluff-raising member is rotated by engagement of said advancing yarn with said member.

3. An improved apparatus according to claim 1, comprising drive means for rotating said fluff-raising member.

4. An improved apparatus according to claim 3, in which said drive means comprises a pulley on said fluff-raising member and means for guiding said advancing yarn over said pulley to drive said pulley and thereby drive said fluff-raising member.

5. An improved apparatus according to claim 3, in which said drive means comprises a fluid drive rotor on said fluffraising member and means for ejecting fluid on said rotor to drive said rotor and said fluff-raising member.

6. An improved apparatus according to claim 5, in which said rotor comprises vanes disposed to receive said ejected fluid.

7. An improved apparatus according to claim 3, in which said drive means comprises a fluid drive rotor and suction means for producing a fluid flow to drive said rotor and said fluff-raising member.

8. An improved apparatus according to claim 7, in which said rotor comprises vanes disposed to receive fluid flow produced by said suction means.

9. An improved apparatus according to claim 3, in which said drive means comprises means connecting said fluff-raising member with said means for advancing said yarn.

10. An improved apparatus according to claim 1, in which the axis of rotation of said fluff-raising member is inclined to the central axis of said balloon at an angle greater than and less than 11. An improved apparatus according to claim 1, in which said fluff-raising member is cylindrical.

12. An improved apparatus according to claim 1, in which said fluff-raising member has a transverse cross-sectional profile that varies at different points along the axis of said member.

13. An improved apparatus according to claim 1, in which said fluff-raising member is of circular cross section.

14. An improved apparatus according to claim 1, in which said fluff-raising member is of polygonal cross section.

15. An improved apparatus according to claim 1, in which said fluff-raising means comprises a plurality of flufi-raising members of different cross-sectional size.

16. An improved apparatus according to claim 1, in which the yam-engaging surface of said fluff-raising member is abrasive.

17. An improved apparatus according to claim 1, in which said cutting elements of said fluff-raising member comprise knife edges.

18. An improved apparatus according to claim 1, in which said fluff-raising member is provided with a screw-thread-like surface engaged by said ballooning yarn.

19 An improved apparatus according to claim 1, in which said balloon-producing means comprises a ring-twisting mechanism.

20. An improved apparatus according to claim 19, in which said ring-twisting mechanism comprises a ring rail and a snail guide, the distance between said ring rail and snail guide being maintained constant.

21. An improved apparatus according to claim 1, in which said balloon producing means comprises a double-twister-type mechanism.

22. An improved apparatus according-to claim 1, in which said balloon-producing means comprises a false-twisting mechanism having a false-twisting spindle.

23. An improved method for manufacturing a fluffy yarn from a multifilament yarn, which comprises advancing said yarn from a supply, producing a balloon in said advancing yarn stabilizing said balloon to maintain the ballooning condition of said yarn substantially constant, taking up said yarn from said balloon and engaging said ballooning yarn externally of said balloon with rotating fluff-raising means having fluffraising elements severing filaments of said multifilament yarn and producing a fluff on said yarn.

Claims

5. An improved apparatus according to claim 3, in which said drive means comprises a fluid drive rotor on said fluff-raising member and means for ejecting fluid on said rotor to drive said rotor and said fluff-raising member.

10. An improved apparatus according to claim 1, in which the axis of rotation of said fluff-raising member is inclined to the central axis of said balloon at an angle greater than 0* and less than 90* .

11. An improved apparatus according to claim 1, in which said fluff-raising member is cylindrical.

15. An improved apparatus according to claim 1, in which said fluff-raising means comprises a plurality of fluff-raising members of different cross-sectional size.

16. An improved apparatus according to claim 1, in which the yarn-engaging surface of said fluff-raising member is abrasive.

19. An improved apparatus according to claim 1, in which said balloon-producing means comprises a ring-twisting mechanism.

22. An improved appAratus according to claim 1, in which said balloon-producing means comprises a false-twisting mechanism having a false-twisting spindle.

23. An improved method for manufacturing a fluffy yarn from a multifilament yarn, which comprises advancing said yarn from a supply, producing a balloon in said advancing yarn stabilizing said balloon to maintain the ballooning condition of said yarn substantially constant, taking up said yarn from said balloon and engaging said ballooning yarn externally of said balloon with rotating fluff-raising means having fluff-raising elements severing filaments of said multifilament yarn and producing a fluff on said yarn.