US3276196A - Pulling device for woolen yarn drafting arrangements - Google Patents

Pulling device for woolen yarn drafting arrangements Download PDF

Info

Publication number
US3276196A
US3276196A US432119A US43211965A US3276196A US 3276196 A US3276196 A US 3276196A US 432119 A US432119 A US 432119A US 43211965 A US43211965 A US 43211965A US 3276196 A US3276196 A US 3276196A
Authority
US
United States
Prior art keywords
yarn
pulling device
rod
rodlike
pulling
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US432119A
Inventor
Grunder Hans-Rudolf
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Maschinenfabrik Rieter AG
Original Assignee
Maschinenfabrik Rieter AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from CH232264A external-priority patent/CH433072A/en
Application filed by Maschinenfabrik Rieter AG filed Critical Maschinenfabrik Rieter AG
Application granted granted Critical
Publication of US3276196A publication Critical patent/US3276196A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • DTEXTILES; PAPER
    • D01NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01HSPINNING OR TWISTING
    • D01H7/00Spinning or twisting arrangements
    • D01H7/92Spinning or twisting arrangements for imparting transient twist, i.e. false twist
    • D01H7/923Spinning or twisting arrangements for imparting transient twist, i.e. false twist by means of rotating devices
    • DTEXTILES; PAPER
    • D01NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01HSPINNING OR TWISTING
    • D01H13/00Other common constructional features, details or accessories
    • D01H13/04Guides for slivers, rovings, or yarns; Smoothing dies
    • DTEXTILES; PAPER
    • D01NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01HSPINNING OR TWISTING
    • D01H2700/00Spinning or twisting machines; Drafting devices
    • D01H2700/247Guilding means for veil or sliver on drafting systems

Definitions

  • a stationary oblong transverse yarn guide which is placed normal to said straight line.
  • a second oblong transverse yarn guide intersects the aforesaid straight line adjacent to said stationary yarn guide, is placed normal to said straight line, and rotates around an axis substantially coinciding with said straight line and extending through the middle of the yarn guides so that the spinning material traveling from one pair of rolls to the second pair of rolls is deflected, i.e. pulled, at each revolution of the rotating yarn guide.
  • the aforedescribed yarn guides which are preferably in the form of smooth, cylindrical rods have the disadvantage that the extent of the yarn deflection is not definitely controlled and that there is no possibility of effecting additional pullings at each revolution of the second yarn guide.
  • the rod may be provided with annular bulges or recesses whereby the bulges as well as the recesses diminish from the center of rotation to the outside.
  • An additional feature of the yarn guide according to the invention resides in the provision of the zone containing the axis of rotation of the guide between two neighboring zones wherein the active diameter of the guide is relatively great, This limits the amplitudes of the yarn deflection. By permitting the yarn to jump from one recess into another the pulling frequency can be increased.
  • FIG. 1 is a schematic longitudinal sectional view of a drafting arrangement including a false twist device provided with pulling means according to the invention.
  • FIG. 2 is a side view of a portion of a yarn guide forming part of the pulling means shown in FIG. 1.
  • FIG. 3 is a side view of a portion of a modified yarn guide.
  • FIG. 4 is a side View of a portion of a further modification of a yarn guide which may be used in the pulling device shown in FIG. 1.
  • FIG. 5 is a side view of a portion of yet another modi- 3,276,196 Patented Oct. 4, 1966 Ice fication of a yarn guide according to the invention.
  • FIG. 6 is a side view of a portion of a further modification of a yarn guide according to the invention.
  • FIG. 7 is a side view of a portion of a further variation of a yarn guide according to the invention.
  • FIG. 8 is a cross sectional view of the yarn guide shown in FIG. 7.
  • FIG. 9 shows a portion of another variation of a yarn guide according to the invention.
  • FIG. 10 shows a cross section of the yarn guide illustrated in FIG. 9.
  • FIGURE 1 of the drawing numerals 1 and 2 designate roller pairs confining a drafting field.
  • a stationary bushing 4 mounted on frame 3 rotatably supports a funnel element 5 on the lower end of which needles 9 forming a funnel are mounted which impart a false twist to a spinning material 6.
  • the spinning material leaving the delivery rollers 2 moves onto a cop, not shown.
  • a transverse rod 7 is mounted to the lower end of the bushing 4 which rod is placed substantially diametrioal with respect to the bushing and normal to the path of the yarn 6.
  • the lower end 8 of the needle funnel element 5 supports a transverse rod 10 diametrical of the element 5 to rotate therewith around a rotation axis extending through the center of the rod 10.
  • the distance between the stationary rod 7 and the rotating rod 10 in the direction of the path of the yarn is such that the spinning material can easily pass between the rods, also when the rods are in parallel position with respect to one another.
  • the yarn may be on the left side of the stationary rod, as shown in FIGURE 1.
  • the rotating rod 10 pushes the yarn along the side of the rod 7 until the friction between the yarn and the rods becomes so great that sliding of the yarn along the rods is prevented.
  • the yarn then passes between the rods 7 and 10 along an S-shaped path and snaps back into the initial position when the rod 10 has completed a full turn.
  • the element 5, 8, 10 which is rotated by a cord drive, not shown, makes about 2000 to 3000 revolutions per minute so that the yarn is subjected to 2000 to 3000 pulls per minute while passing through the drafting arrangement,
  • the rotating rod 10 has an undulated surface 11, the rotation axis 12 of the rod coinciding with a reduced diameter portion of the rod.
  • FIGURE 3 shows a rod having axially spaced annular projections 13 whose outer diameter decreases with increasing distance from the rotation axis 12.
  • the rotating rod 14 is provided with annular recesses or grooves 15 whose bottom diameter increases with increasing distance of the grooves from the rotation axis 12 of the rod i.e. from the center of the rod.
  • FIGURE 5 shows a rod having annular recesses or grooves 16 placed closely to one another and whose bottom diameter decreases with increasing distance from the rotation axis. With this structure the deflection of the yarn is reduced without reduction of the pulling frequency.
  • FIGURE 6 shows an undulated rod 17, a wave trough 18 coinciding with the rotation axis 12.
  • FIGURES 7 to 10 show a rod having protuberances 19 with recesses therebetween in a plane which is normal to the rotation axis 12 of the rod.
  • the rod proper which carries the protuberances may have a circular cross section as shown in FIGURE 8 or may have a rectangular cross section as shown in FIGURE 10.
  • a slot 20 as shown in FIGURE 11 may be placed diametrically of the bushing 4 for guiding the spinning material.
  • the edges 21 3 of the element forming the slot may be curved, for example undulated.
  • a pulling device for periodically pulling woolen yarn passing through a drafting arrangement comprising:
  • a rotating yarn guide constituted by a rodlike element placed in the drafting arrangement normal to the direction of movement of the yarn and rotatable around an axis extending through the center of said element and substantially coinciding with the path of the yarn, said yarn guides being placed at a small distance from one another for affording passage of the yarn between said guides,
  • said rodlike element having a surface curved several times in opposite directions and longitudinally of said rodlike element.
  • a pulling device wherein the rotation axis of said rodlike element extends through a wave trough formed by the undulated element.
  • a pulling device according to claim 5 wherein the outer diameter of said projection decreases with increasing distance of the projections from the rotation axis of said element.
  • a pulling device wherein the depth of said recesses is greatest at the center of said element and decreases with increasing distance of the recesses from the rotation axis of the element.
  • a pulling device wherein the depth of said recesses is smallest at the center of said element and increases with increasing distance of the recesses from the rotation axis of the element.
  • a pulling device for periodically pulling woolen yarn passing through a drafting arrangement comprismg:
  • a rotating yarn guide constituted by a rodlike element placed in the drafting arrangement substantially normal to the direction of movement of the yarn and rotatable around an axis extending through the center of said element and substantially coinciding with the path of the yarn, said yarn guides being placed at a small distance from one another for affording passage of the yarn between said guides,
  • said rodlike element having portions of relatively great diameter alternating with portions of relatively small diameter longitudinally of the element for forming an undulatory surface of said element, said rotation axis extending between portions of said element having relatively great diameters.
  • a pulling device for periodically pulling woolen yarn passing through a drafting arrangement comprising:
  • a stationary yarn guide member placed in the drafting arrangement and having a slot placed transversely to the direction of movement of the yarn, the yarn passing through said slot, and
  • a rotating yarn guide in the form of a rodlike element placed in the drafting arrangement substantially normal to the direction of movement of the yarn and rotatable around an axis extending through the center of said element and substantially coinciding with the path of the yarn, said member and said rotating yarn guide being placed at a small distance from one another for afiording passage of the yarn between said member and said rodlike element when said rodlike elernent is parallel with said slot,
  • said rodlike element having a surface curved several times in opposite directions and longitudinally of said rodlike clement.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Textile Engineering (AREA)
  • Spinning Or Twisting Of Yarns (AREA)
  • Treatment Of Fiber Materials (AREA)

Description

Oct. 4, 1966 HANS RUDOLF GRUNDER 3,276,196
PU LLING DEVICE FOR WOOLEN YARN DRAFTING ARRANGEMENTS Filed Feb. 12. 1965 IN VEN TOR Hfl zvs- Rum LF. GRUNDER TTORA/EX.
United States Patent 3,276,196 PULLIN G DEVICE FOR WOOLEN YARN DRAFTING ARRANGEMENTS Hans-Rudolf Grunder, Winterberg, Switzerland, assignor to Rieter Machine Works Ltd., Winterthur, Switzerland, a corporation of Switzerland Filed Feb. 12, 1965, Ser. No. 432,119 Claims priority, application Switzerland, Feb. 25, 1964, 2,322/ 64 12 Claims. (CI. 57-51) The present invention relates to a pulling device for Woolen yarn drafting arrangements including a false twist element in the drafting field, as shown in the patent application Ser. No. 354,676 of March 25, 1964 of E.
F. Hoyler.
In the pulling device disclosed in the aforesaid patent application and provided in a drafting arrangement including two pairs of rolls for drafting roving the straight line connecting the nips of the pairs of rolls which define the drafting field, is intersected by a stationary oblong transverse yarn guide which is placed normal to said straight line. A second oblong transverse yarn guide intersects the aforesaid straight line adjacent to said stationary yarn guide, is placed normal to said straight line, and rotates around an axis substantially coinciding with said straight line and extending through the middle of the yarn guides so that the spinning material traveling from one pair of rolls to the second pair of rolls is deflected, i.e. pulled, at each revolution of the rotating yarn guide.
The aforedescribed yarn guides which are preferably in the form of smooth, cylindrical rods have the disadvantage that the extent of the yarn deflection is not definitely controlled and that there is no possibility of effecting additional pullings at each revolution of the second yarn guide.
It is an object of the present invention to provide pulling means which avoid the aforesaid disadvantages of the aforedescribed pulling means by providing guides in the form of rods whose surface is curved several times longitudinally of the rods. This may be accomplished by undulating the rods or by undulating only the surface of the rods. In a modification the rod may be provided with annular bulges or recesses whereby the bulges as well as the recesses diminish from the center of rotation to the outside.
An additional feature of the yarn guide according to the invention resides in the provision of the zone containing the axis of rotation of the guide between two neighboring zones wherein the active diameter of the guide is relatively great, This limits the amplitudes of the yarn deflection. By permitting the yarn to jump from one recess into another the pulling frequency can be increased.
The novel features which are considered characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, and additional objects and advantages thereof will best be understood from the following description of embodiments thereof when read in connection with the accompanying drawing, wherein FIG. 1 is a schematic longitudinal sectional view of a drafting arrangement including a false twist device provided with pulling means according to the invention.
FIG. 2 is a side view of a portion of a yarn guide forming part of the pulling means shown in FIG. 1.
FIG. 3 is a side view of a portion of a modified yarn guide.
FIG. 4 is a side View of a portion of a further modification of a yarn guide which may be used in the pulling device shown in FIG. 1.
FIG. 5 is a side view of a portion of yet another modi- 3,276,196 Patented Oct. 4, 1966 Ice fication of a yarn guide according to the invention.
FIG. 6 is a side view of a portion of a further modification of a yarn guide according to the invention.
FIG. 7 is a side view of a portion of a further variation of a yarn guide according to the invention.
FIG. 8 is a cross sectional view of the yarn guide shown in FIG. 7.
FIG. 9 shows a portion of another variation of a yarn guide according to the invention.
FIG. 10 shows a cross section of the yarn guide illustrated in FIG. 9.
Referring more particularly to FIGURE 1 of the drawing numerals 1 and 2 designate roller pairs confining a drafting field. A stationary bushing 4 mounted on frame 3 rotatably supports a funnel element 5 on the lower end of which needles 9 forming a funnel are mounted which impart a false twist to a spinning material 6. The spinning material leaving the delivery rollers 2 moves onto a cop, not shown. A transverse rod 7 is mounted to the lower end of the bushing 4 which rod is placed substantially diametrioal with respect to the bushing and normal to the path of the yarn 6. The lower end 8 of the needle funnel element 5 supports a transverse rod 10 diametrical of the element 5 to rotate therewith around a rotation axis extending through the center of the rod 10. The distance between the stationary rod 7 and the rotating rod 10 in the direction of the path of the yarn is such that the spinning material can easily pass between the rods, also when the rods are in parallel position with respect to one another.
Pulling the yarn is effected as follows: The yarn may be on the left side of the stationary rod, as shown in FIGURE 1. The rotating rod 10 pushes the yarn along the side of the rod 7 until the friction between the yarn and the rods becomes so great that sliding of the yarn along the rods is prevented. The yarn then passes between the rods 7 and 10 along an S-shaped path and snaps back into the initial position when the rod 10 has completed a full turn. The element 5, 8, 10 which is rotated by a cord drive, not shown, makes about 2000 to 3000 revolutions per minute so that the yarn is subjected to 2000 to 3000 pulls per minute while passing through the drafting arrangement,
In the embodiment of the invention shown in FIGURE 2 the rotating rod 10 has an undulated surface 11, the rotation axis 12 of the rod coinciding with a reduced diameter portion of the rod.
FIGURE 3 shows a rod having axially spaced annular projections 13 whose outer diameter decreases with increasing distance from the rotation axis 12.
In the modification shown in FIGURE 4 the rotating rod 14 is provided with annular recesses or grooves 15 whose bottom diameter increases with increasing distance of the grooves from the rotation axis 12 of the rod i.e. from the center of the rod.
FIGURE 5 shows a rod having annular recesses or grooves 16 placed closely to one another and whose bottom diameter decreases with increasing distance from the rotation axis. With this structure the deflection of the yarn is reduced without reduction of the pulling frequency.
FIGURE 6 shows an undulated rod 17, a wave trough 18 coinciding with the rotation axis 12.
FIGURES 7 to 10 show a rod having protuberances 19 with recesses therebetween in a plane which is normal to the rotation axis 12 of the rod. The rod proper which carries the protuberances may have a circular cross section as shown in FIGURE 8 or may have a rectangular cross section as shown in FIGURE 10.
In lieu of the stationary rod 7 a slot 20 as shown in FIGURE 11 may be placed diametrically of the bushing 4 for guiding the spinning material. The edges 21 3 of the element forming the slot may be curved, for example undulated.
What is claimed is:
1. A pulling device for periodically pulling woolen yarn passing through a drafting arrangement, comprising:
a stationary yarn guide placed in the drafting arrangement transversely to the direction of movement of the yarn and engaging with the yarn, and
a rotating yarn guide constituted by a rodlike element placed in the drafting arrangement normal to the direction of movement of the yarn and rotatable around an axis extending through the center of said element and substantially coinciding with the path of the yarn, said yarn guides being placed at a small distance from one another for affording passage of the yarn between said guides,
said rodlike element having a surface curved several times in opposite directions and longitudinally of said rodlike element.
2. A pulling device as defined in claim 1 wherein said rodlike element is undulated.
3. A pulling device according to claim 2 wherein the rotation axis of said rodlike element extends through a wave trough formed by the undulated element.
4. A pulling device as defined in claim 1 wherein said rodlike element has an undulated surface.
5. A pulling device as defined in claim 1 wherein said rodlike element has a plurality of annular projections coaxial with and spaced longitudinally of said rodlike element.
6. A pulling device according to claim 5 wherein the outer diameter of said projection decreases with increasing distance of the projections from the rotation axis of said element.
7. A pulling device as defined in claim 1 wherein said rodlike element has a plurality of annular recesses coaxial with and spaced longitudinally of said element.
8. A pulling device according to claim 7, wherein the depth of said recesses is greatest at the center of said element and decreases with increasing distance of the recesses from the rotation axis of the element.
9. A pulling device according to claim 7 wherein the depth of said recesses is smallest at the center of said element and increases with increasing distance of the recesses from the rotation axis of the element.
10. A pulling device as defined in claim 1 wherein said rodlike element is provided with a plurality of recesses in a plane normal to the path of the yarn.
5 11. A pulling device for periodically pulling woolen yarn passing through a drafting arrangement, comprismg:
a stationary yarn guide placed in the drafting arrangement transversely to the direction of movement of the yarn and engaging with the yarn, and
a rotating yarn guide constituted by a rodlike element placed in the drafting arrangement substantially normal to the direction of movement of the yarn and rotatable around an axis extending through the center of said element and substantially coinciding with the path of the yarn, said yarn guides being placed at a small distance from one another for affording passage of the yarn between said guides,
said rodlike element having portions of relatively great diameter alternating with portions of relatively small diameter longitudinally of the element for forming an undulatory surface of said element, said rotation axis extending between portions of said element having relatively great diameters.
12. A pulling device for periodically pulling woolen yarn passing through a drafting arrangement comprising:
a stationary yarn guide member placed in the drafting arrangement and having a slot placed transversely to the direction of movement of the yarn, the yarn passing through said slot, and
a rotating yarn guide in the form of a rodlike element placed in the drafting arrangement substantially normal to the direction of movement of the yarn and rotatable around an axis extending through the center of said element and substantially coinciding with the path of the yarn, said member and said rotating yarn guide being placed at a small distance from one another for afiording passage of the yarn between said member and said rodlike element when said rodlike elernent is parallel with said slot,
said rodlike element having a surface curved several times in opposite directions and longitudinally of said rodlike clement.
References Cited by the Examiner UNITED STATES PATENTS 731,883 6/1903 Fredenburgh 5777.35
FOREIGN PATENTS 1,317,476 1/1963 France.
650,950 3/1951 Great Britain. 615,223 1/1961 Italy.
0 FRANK I. COHEN, Primary Examiner.
I. PETRAKES, Assistant Examiner.

Claims (1)

1. A PULLING DEVICE FOR PERIODICALLY PULLING WOOLEN YARN PASSING THROUGH A DRAFTING ARRANGEMENT, COMPRISING: A STATIONARY YARN GUIDE PLACED IN THE DRAFTING ARRANGEMENT TRANSVERSELY TO THE DIRECTION OF MOVEMENT OF THE YARN AND ENGAGING WITH THE YARN, AND A ROTATING YARN GUIDE CONSTITUTED BY A RODLIKE ELEMENT PLACED IN THE DRAFTING ARRANGEMENT NORMAL TO THE DIRECTION OF MOVEMENT OF THE YARN AND ROTATABLE AROUND AN AXIS EXTENDING THROUGH THE CENTER OF SAID ELEMENT AND SUBSTANTIALLY COINCIDING WITH THE PATH OF THE YARN, SAID YARN GUIDES BEING PLACED AT A SMALL DISTANCE FROM ONE ANOTHER FOR AFFORDING PASSAGE OF THE YARN BETWEEN SAID GUIDES, SAID RODLIKE ELEMENT HAVING A SURFACE CURVED SEVERAL TIMES IN OPPOSITE DIRECTIONS AND LONGITUDINALLY OF SAID RODLIKE ELEMENT.
US432119A 1964-02-25 1965-02-12 Pulling device for woolen yarn drafting arrangements Expired - Lifetime US3276196A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH232264A CH433072A (en) 1963-04-08 1964-02-25 Plucking device in carded yarn drawing systems

Publications (1)

Publication Number Publication Date
US3276196A true US3276196A (en) 1966-10-04

Family

ID=4231091

Family Applications (1)

Application Number Title Priority Date Filing Date
US432119A Expired - Lifetime US3276196A (en) 1964-02-25 1965-02-12 Pulling device for woolen yarn drafting arrangements

Country Status (3)

Country Link
US (1) US3276196A (en)
DE (1) DE1510756A1 (en)
GB (1) GB1084767A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3350869A (en) * 1964-07-09 1967-11-07 Klinger Mfg Co Ltd Apparatus relating to false twisting
US20190085486A1 (en) * 2017-09-21 2019-03-21 Coretek Fibers Ltd. Spiral yarn structure, manufacturing method and manufacturing device thereof and textile utilizing the same

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US731883A (en) * 1902-12-24 1903-06-23 George A Fredenburgh Twisting-head for thread-dressing machines.
GB650950A (en) * 1943-04-10 1951-03-07 Ede Hegedus Improvements in and relating to temporary-twist devices in textile spinning or twisting machines
FR1317476A (en) * 1962-02-21 1963-02-08 Klinger Mfg Co Ltd Improvements to false torsion devices

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US731883A (en) * 1902-12-24 1903-06-23 George A Fredenburgh Twisting-head for thread-dressing machines.
GB650950A (en) * 1943-04-10 1951-03-07 Ede Hegedus Improvements in and relating to temporary-twist devices in textile spinning or twisting machines
FR1317476A (en) * 1962-02-21 1963-02-08 Klinger Mfg Co Ltd Improvements to false torsion devices

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3350869A (en) * 1964-07-09 1967-11-07 Klinger Mfg Co Ltd Apparatus relating to false twisting
US20190085486A1 (en) * 2017-09-21 2019-03-21 Coretek Fibers Ltd. Spiral yarn structure, manufacturing method and manufacturing device thereof and textile utilizing the same
US10914022B2 (en) * 2017-09-21 2021-02-09 Coretek Fibers Ltd Spiral yarn structure, manufacturing method and manufacturing device thereof and textile utilizing the same

Also Published As

Publication number Publication date
GB1084767A (en) 1967-09-27
DE1510756A1 (en) 1970-04-09

Similar Documents

Publication Publication Date Title
US2590374A (en) Yarn twister for spinning frames
US3225533A (en) Apparatus and process for forming yarns and other twisted assemblies
US4069656A (en) Composite spun yarn and process for producing the same
US4665687A (en) Spinning device for open-end spinning
US3092953A (en) Method and apparatus for forming yarn
KR19990087402A (en) Reduced thread breaks in yarn spinning or twisting processes
US3805505A (en) Thread drawoff tube construction for open end spinning machines
US3276196A (en) Pulling device for woolen yarn drafting arrangements
US2745239A (en) Twist control balloon inclosure
US3394538A (en) Spun yarn
US4399952A (en) Thread delivery apparatus
US3645081A (en) Machine for crimping thermoplastic filament
US3255579A (en) Production of composite stretch yarns
US6269623B1 (en) Open-end rotor spinning arrangement
CN102618986B (en) Processing device for spinning core structure functional yarn
US2221869A (en) Device for producing staple fiber yarns from continuous filaments
JPS6328940A (en) Circular loom
US3695020A (en) Twister and method of twisting
US2622388A (en) Spindle for spinning frames
US3336742A (en) Yarn twist controlling device
CN108425162B (en) Winding Machine
US3611695A (en) Open end spinning
JPS5855254B2 (en) design thread
US2914904A (en) Cord twister and winder
US4434612A (en) False twist drafting device for continuous working of slubbings of textile materials