US3217376A

US3217376A - Yarn crimping apparatus

Info

Publication number: US3217376A
Application number: US239607A
Authority: US
Inventors: Claude M Irwin; Euell K Mcintosh
Original assignee: Monsanto Co
Current assignee: Monsanto Co
Priority date: 1962-11-23
Filing date: 1962-11-23
Publication date: 1965-11-16
Anticipated expiration: 1982-11-16

Description

1955 c. M. IRWIN ETAL 3,

YARN CRIMPING APPARATUS Filed Nov. 25, 1962 2 Sheets-Sheet 1 AIR SUPPLY CONTROLLER INVENTOR. E. K. M1N705H BY 61 M [PW/1V J m (T ATTORNEY Nov. 16, 1965 c. M. IRWIN ETAL 3,217,376

YARN CRIMPING APPARATUS Filed Nov. 25. 1962 2 Sheets-Sheet 2 FIG.3.

' vt/m/lfi W FIG.4. INVENTORS ATTORNEY United States Patent 3,217,376 YARN CRHMLING APPARATUS Claude M. Irwin and Euell K. Mcllntosh, Pensacola, Fla, assignors to Monsanto Company, a corporation of Delaware Filed Nov. 23, 1962, Ser. No. 239,607 7 Claims. (Ci. 28--1) This invention relates to textured filament yarn and to a method and apparatus for producing same from colddrawable thermoplastic polymers. More particularly, this invention relates to controlled apparatus and method adapted to produce continuous textured yarns of the nylon type in different intermittent and variable crimped patterns.

Continuous filament yarn modified in some manner to increase its bulk and stretch properties is known as textured yarn. Textured or bulky yarns provide a softer hand, greater insulation and more subdued lustre than non-bulked yarns and are commercially desirable. Continuous filament yarn is rendered bulky by modifying its shape. Some of the different shapes into which continuous filament yarn is deformed for bulking purposes are crimps, coils, curls and loops. This invention is related to the processing of crimped textured yarn. Crimped textured yarn as applied herein refers to continuous filament yarn to which sinusoidal or corrugated deformation stresses in the form of latent crimps are applied to render the yarn potentially crimpable and which latent crimps upon subsequent heat treatment fluff, blossom, or emerge into wavy, true or developed crimps.

Continuous uniformly crimped yarn, that is, yarn having substantially the same size of crimps applied along its continuous length, is produced according to known procedure by feeding and compressing the yarn into a stuifer box so as to cause the individual filaments to fold or bend at a sharp angle upon contact with a wall surface.

Continuous uniformly crimped yarn is also produced by delivering the yarn to a heat stretch zone for heating and stretching the yarn, stressing the yarn by passing it between intermeshing denticulated wheels, and thereafter applying heat to the yarn to develop the stresses in the form of corrugated crimps.

It is often desirable for styling reasons in such end uses as dress goods, draperies, upholstery and the like to produce textured yarns which have intervaled or intermittent crimps applied along its length. The crimped and uncrimped sections of the continuous yarn when in the end product reflect differences of lustre as well as variances in bulk thereby offering contrasting end pattern effects.

It is an object of this invention to provide a method and apparatus adapted for effecting controlled crimping of continuous filament yarn.

Another object of the invention is to provide a method and apparatus for controlling the amplitude of the crimps applied to continuous filament yarn.

Another object is to provide controlled apparatus flexible in operation so as to produce many different patterns of crimped yarn.

Another object is to provide a textured yarn having a regular or irregular pattern of intermittent and variable crimps.

A further object is to provide a method and apparatus to produce continuous uniformly crimped yarn, continuous variably crimped yarn, intermittent-uniformly crimped yarn having a regular or irregular interval patice tern and intermittent-variably crimped yarn having a regular or an irregular interval pattern.

A still further object is to provide a simple, rapid and economical method and apparatus for producing a thermoplastic continuous multifilament or monofilament yarn having a fiutfy, stretchable characteristic with intermittent and variable pattern features.

Other objectives and advantages of the present invention will become apparent from the detailed description which follows and the accompanying drawing. In the drawing:

FIGURE 1 is a schematic view with principal parts in location illustrating an operative embodiment of the method and apparatus of the invention for producing latently crimped yarn.

FIGURE 2 is an elevation view partially in crosssection of the draw and crimp assembly showing the components thereof in crimping position.

FIGURE 3 is a view similar to that shown in FIGURE 2 illustrating the draw and crimp assembly in a non-crimping position.

FIGURE 4 is an elevation view showing the novel yarn produced having an intermittent-variable crimped profile applied at regular intervals along its length.

FIGURE 5 is an elevation view showing another novel yarn produced having an intermittent-variable crimped profile applied at irregular intervals along its length.

FIGURE 6 is a schematic view showing the apparatus and method for developing the texture of the latently crimped yarn.

The yarn texturizing apparatus embodying the invention, in one preferred form and operation, comprises driven feed roll means for feeding a yarn delivered thereto to a rotatable draw and crimp means including a pair of separable denticulated rolls which are operatively driven at a faster peripheral rate of speed than the feed roll means so as to draw the yarn normally laced therebetween. The denticulated rolls are adapted to be positioned to a closely spaced intermeshed position to cooperatively apply deformation stresses or latent crimps to the yarn passing therethrough or to an out-of-mesh position to provide an uncriinped section in the yarn by actuator means yieldably connected thereto. The actuator means acts responsively to a control valve means which is connected to a source of air under pressure and to a timing means. The timing means, which is connected to a source of electrical energy, operates the control valve means to alternately connect the actuator means for a preselected period of time to the source of air under pressure for positioning the denticulated rolls of the draw and crimp means to their intermeshed position for crimping the yarn passing therebetween, and then to simultaneously cut off the flow of air to and to vent the air from the actuator means for positioning the denticulated rolls to their out-of-mesh position for discontinuing deformation of the yarn for a preselected period of time. By continuous repetition of the above sequence, the yarn is latently crimped at intermittent intervals along its axis. After being latently crimped, the yarn preferably is taken up by a conventional take-up device. The yarn before or after being taken up can be heat treated under low tension to develop the latent crimps in the yarn.

A controller means is interposed between the control means and the source of air supply to selectively regulate the pressure of air supplied to the actuator means when it is desired to vary the amplitude of the crimps in the crimped sections of the yarn. Regulating the air pressure supplied to the control means between a predetermined range of values determines the adjusted intermeshed position of the denticulated rolls relative to one another and consequently the degree of deformation stress applied to the yarn. By changing the timing sequence of the timing means, the length of the crimped and uncrimped sections in the yarn is controlled to provide a regular or an irregular pattern of crimped to uncrimped sections.

The novel method for producing intermittent-variable crimped yarn comprises the steps of providing a source of molecularly orientable synthetic continuous filament yarn made from a thermoplastic polymer and continuously advancing the orientable yarn longitudinally through a heat stretch zone wherein the temperature of the yarn is elevated and the yarn is attenuated a predetermined extent thereby increasing its molecular orientation thereof. Most of the attenuation is localized in the area where the yarn temperature is elevated. Thereafter intermittent and variable latent deformation stresses or crimps are imparted to the yarn at either regular or irregular intervals along its length thereof by passing the yarn between controlled alternately intermeshing and unmeshing peripherally denticulated rolls. The latently crimped yarn is then subjected to heat whereupon the latent crimps develop into truly textured crirnps. The textured yarn is thereafter collected on any conventional yarn take-up device.

One type of novel yarn which is produced with the method and apparatus of the invention has repetitive sections of vari-dimensional sinusoidal crimps applied intermittently and at equally distanced intervals along the length thereof, the amplitude of the crimps being variable in the different crimped sections thereof. Another type produced is similar to the one described above but the crimped and uncrimped sections are of unequal length along the longitudinal axis of the yarn.

Referring to FIGURES 1, 2, 3 and 6 of the drawings, the apparatus for producing textured yarn embodying the invention includes a feed roll assembly having a pair of

surface engaging rolls

1 and 2 for forwarding a yarn 3 such as nylon, from a packaged source thereof as bobbin 4, to a draw and crimping device 5. One of the rolls, roll 2, is positively driven by suitable power means at a predetermined rate of speed so that the yarn forwarded by

rolls

1 and 2 is nipped therebetween. To properly tension and guide the yarn traveling to the feed roll as sembly from bobbin 4, the yarn is directed engagingly around a tension guide s and thence through a pigtail guide 7.

A snubbing or draw pin 8 provided with heating means and having a smooth contact surface is located intermediate the feed roll assembly and crimping device 5. Draw pin 8 is mounted to be stationary and axially askew with respect to the axes of the

feed rolls

1, 2 to prevent the yarn normally laced therearound to become superimposed. The skewed position of draw pin 3 causes the yarn to travel in a helical turn thereabout. Draw pin 8 is provided with heating means connected to a source of electrical power by suitable leads so that the yarn normally passed therearound is heated to a predetermined elevated temperature.

The draw and crimping device consists of a yoke 9 which is pivotally supported at one side thereof about a pin 10 secured to a frame 11. A crimp roll 12, having an axial bore extending therethrough and a spur gear 13, preferably integrally formed therewith at one end thereof, is rotatably mounted as by bearings on a spindle 14 journaled at its ends within yoke 9. Crimp roll 12 has a continuous toothed or denticulated peripheral surface at its end opposite spur gear 13. A second peripherally denticulated crimp roll 15, similar to crimp roll 12, is securely mounted on the end of a driven shaft 16 which is journaled in frame 11 and which is driven by suitable power means. Crimp roll has a spur gear 17 integrally formed at its one end thereof.

Crimp rolls 12, 15 are arranged in close relation with their axes normally being parallel and their respective spur gears 13, 17 being in meshing engagement for constantly driving the crimp rolls 12, 15. When crimp rolls 12, 15 are in parallel alignment the denticles or teeth on the rolls are constructed to intermesh in closely spaced relation therebetween without actually contacting each other. The denticles on crimp rolls 12, 15 are finer and much more delicate in construction than gear teeth and extend axially and continuously along the outer periphery of each crimp roll.

A stud bolt 18 is threaded transversely through yoke 9 near its pivoted side thereof and can be screwed in and out of yoke 9 upon loosening a lock nut 19 threaded thereon. The adjusted position of stud bolt 18 determines its point of contact with a stop member 20 in frame 11 so as to variably limit the degree of pivotal rocking of crimp roll 12 toward crimp roll 15 to prevent contact and damage of the teeth thereof.

A separator roll 21 is rotatably mounted at one end thereof on frame 11 adjacent to crimp roll 15. The yarn is normally laced in a plurality of wraps about crimp roll 15 and separator roll 21. The axis of separator roll 21 is slightly tilted in relation to the axis of crimp roll 15 to cause the plural wraps of yarn to travel in spaced relation therearound.

Yoke 9 and crimp roll 12 are angularly rocked in one direction away from crimp roll 15 and about pin 10 by a pneumatic cylinder actuator 22 and in the opposite direction toward crimp roll 15 by a resilient spring 23 connected at one end to yoke 9 and at its opposite end to actuator 22. Actuator 22 has a piston 24 sealingly reciprocable within a casing 25 secured to frame 11. Piston 24 has a stem 26 extending outwardly therefrom at one side thereof. Stem 26 extends outwardly of casing 25 and into contact with yoke 9. At its side opposite stem 26, piston 24 is subject to air under pressure nor mally supplied to a chamber 27 defined in casing 25.-

Chamber 27 is open at one end of a pipe 28 connected to casing 25. Pipe 28 at its other end is connected to a conventional electric-pneumatic three-way type valve 29 and provides communication between the latter and chamber 27. Valve 29 is connected by leads or wires 30 to an electrical timing device 31 which is connected to a source of electrical energy. Valve 29 is also connected by a pipe 32 to a reservoir 33 normally supplied with air under pressure for providing communication therebetween. Valve 29 is positionable to an open position for permitting air to pass from reservoir 33 to the pneumatic cylinder actuator 22 via

pipes

28 and 32 and to a cut-off position for cutting off the flow of air from reservoir 33 while at the same time venting pipe 28 and chamber 27 of actuator 22.

A pressure gauge 34 is interposed in pipe 33 and a con troller 35 is connected to pipe 32. Controller 35,- which may be of the balanced valve type, is normally selectively regulated to permit the pressure of air to build-up in pipe 28 and chamber 27 to a desired value, as will hereinafter be explained, when valve 29 is in its open position. By controlling the pressure of air supplied to chamber 27 of actuator 22 it is possible under one condition of operation to move piston 24 and therefore stem 26 toward yoke 9 so as to pivot crimp roll 12 closer toward crimp roll 15 against the force of spring 23 and under another condition to permit spring 23 to pull yoke 9 and crimp roll 12 away from crimp roll 15.

A yarn twister device 36 is positioned near the crimping device and serves to twist and take-up the yarn delivered thereto from the draw and crimp assembly 5 via a pigtail guide 37. Yarn twister device 36 includes a rotatable bobbin 38 driven by belt and motor means (not shown), and a reciprocable traverse ring 39 operable concentrically about bobbin 38. A ring traveler 40 is slidably mounted on the reciproca'ble ring 39 and serves to carry the yarn around the bobbin 3% while the yarn is taken-up.

It will be understood that any other suitable form of package building apparatus could be used in place of the yarn twister device 36.

To develop the potential crimpability induced in the yarn by the draw and crimp assembly 5 and to simultaneously set the developed crimp, a heat treating device 41 (FIGURE 6) is provided. Device 41 comprises an endless conveyor belt 42 driven by suitable drive means (not shown) and a heating cabinet 43 having a radiant heat applicator means, such as an array of heating lamps 44. Bobbin 38 packaged with latently crimped yarn is doifed or removed from twister device 36 and is positioned near the conveyor belt 42. The yarn from bobbin 38 is extended to a traverse guide 45 which lays the yarn from bobbin 38 onto the belt 42 in a zig-zag pattern. The yarn is carried through the cabinet 43 where it is heat conditioned to develop the latent crimps previously applied. The yarn becomes bulked and is carried by belt 42 outwardly from cabinet 43 where it is advanced to another traverse guide 46 that moves the yarn reciprocably across the face of a take-up bobbin 47. Bobbin 47 is surface driven by a driven roll 48. It is to be understood that other apparatus arrangements can be employed for subjecting the yarn to an elevated temperature while under little or no tension.

In operation, the yarn is initially laced as shown in FIGURE 1. The yarn extends from bobbin 4 to the feed rolls 1, 2 after passing around tension guide 6 and through pigtail guide 7. The yarn then passes between feed rolls 1, 2 and is advanced to the crimp rolls 12, 15 after being laced around draw pin 8. Several successive wraps are taken around roll 15 and separator roll 21, and then the yarn further advances to bobbin 38 of yarn twister device 36 after passing through pigtail guide 37 and ring traveler 40 of the twister device 36, Crimp rolls 12, 15 are arranged to be driven at a certain peripheral rate of speed faster than the peripheral speed of feed rolls 1, 2 to stretch the yarn therebetween.

To produce continuous filament yarn having intermittent crimps along its length, timing device 31 is timed to alternately energize and deenergize the three-way valve 29 to permit communication between the pneumatic cylinder actuator 22 and reservoir 33, and to cut off the air supply therefrom while simultaneously venting actuator 22, respectively, in the above alternate sequence according to any predetermined time interval. Meanwhile, controller 35 is positioned to control the pressure of air delivered to chamber 27 of actuator 22 at a value so as to pivot crimp roll 12 against the force of spring 23 into intermeshing position with crimp roll 15 a desired distance to apply deformation stresses in tthe form of latent crimps in the yarn passing between the rolls. The intermeshing distance between the teeth of

rolls

12, 15 is limited by adjustment of stud bolt '18. Screwing stud bolt 18 inward toward stop member 20 in frame 11, as shown in FIG-

URES

2 and 3, will permit a smaller bite or clearance between the crimp rolls and vice versa.

Assume that valve 29 has been moved to a cut-off position by timing device 31. In this case the flow of airfrom reservoir 33 is cut off from actuator 22, and chamber 27 of the actuator 22 is vented through valve 29. Upon venting of actuator 22, spring 23 pivotally ro'cks yoke 9 and crimp roll 12 about pin away from crimp roll to a position where crimp roll 12 does not engage the yarn as is shown in FIGURE 3. Although the crimp rolls 12, 15 are completely out of mesh, it will be noted that spur gears 13, 16 are angularly engaged and therefore crimp roll 15 will be driven so as to continue to forward yarn 3 to bobbin 38. No crimp is applied to the yarn while actuator 22 is vented.

Assume now that timing device 31 moves valve 29 to an open position, Air under pressure from reservoir 33 then issupplied to chamber 27 of actuator 22. In this case, air under pressure in chamber 27 acts on piston 24 and causes the latter to reciprocate for moving stem 26 outwardly of casing 25. Stem 26 then pivotally and angularly rocks yoke 9 and crimp roll 12 to a position where the crimp rolls 12, 15 intermesh as shown in FIGURE 2. Preferably, the pressure of air should be of such a value so as to rock yoke 9 to a position where stud bolt 18 contacts stop member 26 against the force of spring 23. While the crimp rolls 12, 15 are in their intermeshing position, deformation stresses are applied to the yarn traveling therebetween. The compressive forces are applied to the yarn mostly along the apices of the teeth of

rolls

12, 15. The yarn, before being delivered to the crimp rolls 12, 15, is softened as it passes over heated pin 8 and is therefore readily deformed by the teeth of crimp rolls 12, 15. Because the yarn is under tension traveling between the

rolls

12, 15, the yarn takes a straight path from apex to apex of the teeth of the

rolls

12, 15 such that the material of the yarn is not merely pressed into a corrugated form corresponding to the space between the teeth but has compression tension stresses applied thereto along portions contacting the teeth of the rolls. These stresses are here referred to as latent crimps.

The crimps in the yarn will be vari-dimensional, that is, the convolutions of the crimped yarn will extend radially in many directions when viewed in cross section, according to the number of wraps taken about separator roll 21 and crimp roll 12. It will be noted that where more than one wrap is taken the yarn passes between the crimp rolls 12, 15 a number of times, Due to slight twisting of the yarn between wraps, the yarn does not pass through the

rolls

12, 15 in the same position every time and thus the crimps are applied in different dimensions radially of the yarn axis.

It will be noted that as crimp roll 12 rocks angularly away from crimp roll 15 from a condition where the crimp rolls 12, 15 are in parallel axial alignment, the latent crimps applied nearest the spur gears 13, 16, as viewed in FIGURE 2, will be of slightly greater magnitude than those applied adjacent the outer ends of the crimp rolls opposite the spur gears.

By repeated actuation of valve 29 alternately from open to cut-off position by timing device 31, a latently intermittently crimped yarn is produced. The crimps will be of uniform amplitude or size so long as the air is mainitem??? at a predetermined constant pressure by control- Continuous intermittent-variably crimped yarn having latent crimps of non-uniform amplitude formed along its linear length as shown in FIGURE 4 is produced by varying the pressure of air supplied to chamber 27 of actuator 22 between a range of values necessary for causing interrznseshmg of crimp rolls 12, 15 against the force of spring The length of the latent crimped sections relative to the uncrimped sections on the yarn 3 is controlled by setting timing device 31 according to whether a regular pattern is desired, that is where the length of the crimped and uncrimped sections are equal, or an irregular pattern 1s desired, where the length of the crimped sections relative to the uncrimped sections are different. FIG- URES 4 and 5 show two different types of yarns which can be produced with the described method and apparatus. FIGURE 4 illustrates a yarn having crimped

portions

50, 51 and uncrimped portions 49 wherein the crimped 50, 51 and uncrimped 49 portions are of the same length and where the crimps in portion 50 are of 1a dllferent amplitude than those of portion 51. FIG- URE 5 illustrates a yarn having crimped portions 53, 54 and uncrimped portions 52 wherein the crimped portions 53, 54 are of a different length than the uncrimped portions 52, and where the crimps in portions 54 are not only of a different amplitude than those in portions 53, but are variable within the portions.

The potentially or latently crimped yarn is then takenup on bob-bin 38 and thereafter the yarn from bobbin 38 is laid on conveyor belt 42 and carried into cabinet 43 of heat treating device 41. The application of heat to the latently crimped yarn causes the deformed sections to fluff or bulk. The bulked yarn is carried out of the cabinet 43 and then for a distance along the belt to permit it to cool before it is taken-up on bobbin 46.

It will be understood that if desired, the apparatus of the invention could be used to produce continuously uniformly crimped yarn without any straight uncrimped sections by setting the timing device 31 to maintain the valve 29 constantly in an open position so as to keep crimp rolls 12, constantly intermeshing. The crimp could be varied along the length of the yarn by varying the pressure of the air delivered to chamber 27 of actuator 22 as previously explained. The controlled apparatus and method for producing textured yarn embodying the invention is flexible in operation so as to provide many diiferent selective types of patterned yarns. The apparatus is not costly and is simple in structure and operation and the method is not complicated.

Variations and modifications of the present invention are contemplated within the scope and limitations of the claims.

What is claimed is:

1. Yarn crimping apparatus comprising in combination,

(a) a source of supply of a continuous molecularly orientable synthetic filament yarn made from a thermoplastic polymer,

(b) a driven denticulated crimp roll means adapted to impart latent crimp stresses to said yarn normally having engagement therewith,

(c) driven feed roll means for advancing said yarn from said source of supply to said denticulated crimp roll means at one rate of speed,

(d) said denticulated crimp roll means being adapted to advance said yarn at an increased rate of speed as compared to said one rate of speed so as to stretch the yarn between said feed roll means and said denticulated crimp roll means,

(e) a heated draw pin mounted intermediate said feed roll means and said denticulated crimp roll means for localizing the stretching of said yarn therebetween and for heating the yarn prior to its travel to said denticulated crimp roll means,

(f) a separator roll mounted near and at an angle to said denticulated crimp roll means for preventing superimposing of yarn normally traveling engagingly around said separator roll and said denticulated crimp roll means,

(g) a pneumatic actuator yieldably connected to said denticulated crimp roll means and adapted to alternately position the latter into one position and into a second position,

(h) an electro-pneumatic valve means connected to said pneumatic actuator,

(i) a reservoir normally supplied with air under pressure connected to said electro-pneumatic means,

(j) an electric timing means connected to a source of electrical energy for energizing said electro-pneumatic valve means for supplying air under pressure to said pneumatic actuator to cause the latter to position said denticulated crimp roll means into said one position for applying latent crimps to said yarn advancing therethrough and for de-energizing said electro-pneumatic valve means for cutting oif the flow of air under pressure from said reservoir and venting said pneumatic actuator to position said denticulated crimp roll means to said second position for providing uncrimped sections in said yarn, and

(k) driven yarn take-up means for taking up said latently crimped yarn from said denticulated crimp roll means.

2. Yarn crimping apparatus as claimed in claim 1 further comprising, controller means interposed between said reservoir and said electro-pneumatic valve means 8 and adapted to permit selective control of the pressure of air supplied to said electro-pneumatic valve means and said pneumatic actuator for controlling the latent deformation stresses applied to said yarn by said denticulated crimp roll means.

3. Yarn crimping apparatus comprising in combination,

(b) a frame,

(c) a yoke pivotally arranged on said frame,

(d) one denticulated crimp roll rotatably mounted on said yoke,

(e) a second denticulated crimp roll rotatably mounted on said frame in parallel axial alignment and in closely spaced intermeshing position in relation to said one denticulated crimp roll,

(f) power means for driving said one and said second denticulated crimp rolls in unison at one rate of speed,

(g) a separator roll mounted on said frame adjacent said second denticulated crimp roll,

(h) said yarn normally being delivered to and laced about said separator roll and said second denticulated crimp roll in several successive Wraps,

(i) a pneumatic actuator yieldably connected to said draw and crimp roll means and adapted to alternately position the latter into one position and into a second position,

(j) biasing means fixedly connected at one end thereof and connected to said yoke at its opposite end thereof,

(k) an electro-pneumatic valve means connected to said pneumatic actuator,

(l) a reservoir normally supplied with air under pressure connected to said electro-pneumatic means, (m) an electric timing means connected to a source of electrical energy for energizing said electro-pneumatic valve means for supplying air under pressure to said pneumatic actuator to operatively cause the latter to position said draw and crimp means into said one position for applying latent crimps to said yarn advancing therethrough against the force of said biasing means and for de-energizing said electropneumatic valve means for cutting off the flow of air under pressure from said reservoir and venting said pneumatic actuator to permit said biasing means to position said draw and crimp means to said second position for providing uncrimped sections in said yarn,

(n) driven yarn take-up means for taking up said latently crimped yarn from said draw and crimp roll means, and

(0) controller means interposed between said reservoir and said electro-pneumatic valve means and adapted to permit selective control of the pressure of air supplied to said electro-pneumatic valve means and therefore to said pneumatic actuator for controlling the latent crimp stresses applied to said yarn by said draw and crimp means.

4. Yarn crimping apparatus comprising in combination,

(b) a frame,

(c) a yoke pivotally arranged on said frame,

(d) one denticulated crimp roll rotatably mounted on said yoke,

(e) a second denticulated crimp roll rotatably normally mounted on said frame in parallel axial alignment and in closely spaced intermeshing position in relation to said one denticulated crimp roll,

(i) a pneumatic actuator secured to said frame,

(j) a piston sealingly reciprocable within said pneumatic actuator,

(k) a stem secured at one end to one side of said piston and projecting outwardly from said pneumatic actuator into sliding contact with said yoke at its opposite end thereof,

(1) said pneumatic actuator having a chamber defined therein at the other side of said piston,

(m) a spring connected at one end to said yoke and at its opposite end to said pneumatic actuator for angularly biasing said one denticulated crimp roll away from said second denticulated crimp roll to an out-of-mesh position,

(n) driven feed roll means for advancing said yarn from said source of supply to said second denticulated crimp roll,

() said feed roll means being driven at a slower rate of speed than said second denticulated crimp roll to permit said yarn to be stretched therebetween,

(p) a heated draw pin mounted intermediate said feed roll means and said denticulated crimp rolls for heating and localizing the stretching of said yarn prior to its travel to said denticulated crimp rolls,

(q) electro-pneumatic valve means,

(r) electrical timing means connected to a source of electrical energy and to said valve means,

(5) a pipe connected at one end to said pneumatic actuator and at its opposite end to said valve means for providing communication between said chamber of said pneumatic actuator and said valve means,

(t) a reservoir normally supplied with fluid under pressure,

(u) a pipe connecting said reservoir to said valve means for establishing communication therebetween,

(v) said valve means being alternately positionable by said timing means to a cut-off position for cutting off the flow of air under pressure from said reservoir to said chamber of said pneumatic actuator and venting the latter to atmosphere to permit said spring to rock said yoke and said one denticulated crimp 7 roll to said out-of-mesh position to provide an uncrimped section in said yarn and positionable to another position for supplying air under pressure from said reservoir to said chamber of said pneumatic actuator to cause said piston and said stem to act responsively thereto against the force of said spring to move said one denticulated crimp roll into said normal intermeshing position with said second dentioulated crimp roll to provide a latently crimped section in said yarn traveling therebetween, and

(w) driven yarn take-up means for taking up said latently crimped yarn from said denticulated crimped rolls.

5. Yarn crimping apparatus as claimed in claim 4 further comprising, limiting means on said yoke and said frame for defining the limit distance of said intermeshing position of said denticulated crimp rolls.

6. Yarn crimping apparatus comprising in combination,

(b) a frame,

(0) a yoke pivotally arranged on said frame,

((1) one crimp roll having peripheral axially extending denticles adjacent one end thereof and a spur gear adjacent the opposite end thereof being rotatably mounted on said yoke,

(e) a second crimp roll having peripheral axially ex- 1Q tending denticles adjacent one end thereof and a spur gear adjacent the opposite end thereof, said, second crimp roll being journaled on said frame and arranged to be positively driven,

(if) said spur gears of said one and said second crimp rolls always being in contact therebetween while said denticles of said one and said second crimp rolls normally being in closely spaced intermeshing position out of contact therebetween,

(h) said yarn normally being delivered to and laced about said second denticulated crimp roll in several successive wraps,

(i) a pneumatic actuator secured to said frame (j) a piston sealingly reciprocable within said pneumatrc actuator,

(in) a spring connected at one end to said yoke and at its opposite end to said pneumatic actuator for angularly biasing said one denticulated crimp roll away from said second denticulated crimp roll to an out-of-mesh position,

(0) said feed r-oll means being driven at a slower rate of speed than said second denticulated crimp roll to permit said yarn to be stretched therebetween,

(q) electro-pneumatic valve means,

(s) a pipe connected at one end to said pneumatic actuator and at its opposite end to said valve means for providing communication between said chamber of said pneumatic actuator and said valve means,

(t) a reservoir normally supplied with fluid under pressure,

(v) said valve means being alternately positionable by said timing means to a cut-off position for cutting 01f the flow of air under pressure from said reservoir to said chamber of said pneumatic actuator and venting the latter to atmosphere to permit said spring to rock said yoke and said one denticulated crimp roll to said out-of-mesh position to provide an uncrimped section in said yarn and positionable to another posi' tion for supplying air under pressure from said reser voir to said chamber of said pneumatic actuator to cause said piston and said stem to act responsively thereto against the force of spring to move said one denticulated crimp roll into said normal intermeshing position with said second denticulated crimp roll to provide a latently crimped section in said yarn traveling therebetween,

(w) driven take-up means for taking up said latently cricrlnped yarn from said denticulated crimped rolls, an

(X) controller means interposed between said reservoir and said electro-pneumatic valve means and adapted to permit selective control of the pressure of air supplied to said electro-pneumatic valve means and therefore to said pneumatic actuator for controlling the latent crimp stresses applied to said yarn by said draw and crimp means.

7. Yarn crimping apparatus as claimed in claim 6 further comprising, limiting means on said yoke and said frame for defining the limit distance of said intermeshing position of said denticulated crimp rolls.

References Cited by the Examiner UNITED STATES PATENTS 2,669,001 2/1954 Keen 2872 2,862,279 12/1958 Fordon et a1. 281

Lohr et a1 2881 Bromley et a1 281 Bohmfalk 28-1 Bromley et a1. 2872 Bromley et a1. 2881 Hills et a1. 281

DONALD W. PARKER, Primary Examiner.

RUSSELL C. MADER, Examiner.

Claims

1. A YARN CRIMPING APPARATUS COMPRISING IN COMBINATION, (A) A SOURCE OF SUPPLY OF A CONTINUOUS MOLECULARLY ORIENTABLE SYNTHETIC FILAMENT YARN MADE FROM A THERMOPLASTIC POLYMER (B) A DRIVEN DENTICULATED CRIMP ROLL MEANS ADAPTED TO IMPART LATENT CRIMP STRESSES TO SAID YARN NORMALLY HAVING ENGAGEMENT THEREWITH, (C) DRIVEN FEED ROLL MEANS FOR ADVANCING SAID YARN FROM SAID SOURCE OF SUPPLY TO SAID DENTICULATED CRIMP ROLL MEANS AT ONE RATE OF SPEED, (D) SAID DENTICULATED CRIMP ROLL MEANS BEING ADAPTED TO ADVANCE SAID YARN AT AN INCREASED RATE OF SPEED AS COMPARED TO SAID ONE RATE OF SPEED SO AS TO STRETCH THE YARN BETWEEN SAID FEED ROLL MEANS AND SAID DENTOCULATED CRIMP ROLL MEANS, (E) A HEATED DRAW PIN MOUNTED INTERMEDIATE SAID FEED ROLL MEANS AND SAID DENTICULATED CRIMP ROLL MEANS FOR LOCALIZING THE STRETCHING OF SAID YARN THEREBETWEEN AND FOR HEATING THE YARN PRIOR TO ITS TRAVEL TO SAID DENTICULATED CRIMP ROLL MEANS, (F) A SEPARATOR ROLL MOUNTED NEAR AND AT AN ANGLE TO SAID DENTICULATED CRIMP ROLL MEANS FOR PREVENTING SUPERIMPOSING OF YARN NORMALLY TRAVELING ENGAGINGLY AROUND SAID SEPARATOR ROLL AND SAID DENTICULATED CRIMP ROLL MEANS, (G) A PNEUMATIC ACTUATOR YIELDABLY CONNECTED TO SAID DENTICULATED CRIMP ROLL MEANS AND ADAPTED TO ALTERNATELY POSITION THE LATTER INTO ONE POSITION AND INTO A SECOND POSITION, (H) AN ELECTRO-PNEUMATIC VALVE MEANS CONNECTED TO SAID PNEUMATIC ACTUATOR, (I) A RESERVOIR NORMALLY SUPPLIED WITH AIR UNDER PRESSURE CONNECTED TO SAID ELECTRO-PNEUMATIC MEANS, (J) AN ELECTRIC TIMING MEANS CONNECTED TO A SOURCE OF ELECTRICAL ENERGY FOR ENERGIZING SAID ELECTRO-PNEUMATIC VALVE MEANS FOR SUPPLYING AIR UNDER PRESSURE TO SAID PNEUMATIC ACTUATOR TO CAUSE THE LATTER TO POSITION SAID DENTICULATED CRIMP ROLL MEANS INTO SAID ONE POSITION FOR APPLYING LATENT CRIMPS TO SAID YARN ADVANCING THERETHROUGH AND FOR DE-ENERGIZING SAID ELECTRO-PNEUMATIC VALVE MEANS FOR CUTTING OFF THE FLOW OF AIR UNDER PRESSURE FROM SAID RESERVOIR AND VENTING SAID PNEUMATIC ACTUATOR TO POSITION AND DENTICULATED CRIMP ROLL MEANS TO SAID SECOND POSITION FOR PROVIDING UNCRIMPED SECTIONS IN SAID YARN, AND (K) DRIVEN YARN TAKE-UP MEANS FOR TAKING UP AND SAID LATENTLY CRIMPED YARN FROM SAID DENTICULATED CRIMP ROLL MEANS.