US3710461A

US3710461A - Method and apparatus for intermittently texturing yarn

Info

Publication number: US3710461A
Application number: US00092018A
Authority: US
Inventors: G Benson; D Potter
Original assignee: Owens Corning Fiberglas Corp
Current assignee: Owens Corning
Priority date: 1970-11-23
Filing date: 1970-11-23
Publication date: 1973-01-16
Anticipated expiration: 1990-01-16
Also published as: NL7116110A; BE775670A; FR2115928A5

Abstract

Apparatus for and method of texturing yarn at spaced apart regions along its length including intermittently supplying fluid under pressure to a yarn texturing nozzle and releasing fluid from the nozzle during time between supply of the fluid.

Description

111 3,710,461 [4 1 Jan. 16, 1973 United States Patent [1 1 Benson et al.

lulll ////4 88881 2222/ "nuns unuz 3 5 l mmmmm CDBBB 67800 66677 99999 HHHHH #7516 75608 72479 J1,3,6,4, mnmmn 3 3 3333 m n R m ome F C S UW m r, X mm Rm BP A 5 at AT Sm N who m i A" now D GDb o w H m T n E w Mm m m m [73] Assignee: Owens-Corning Fiberglas Corpora- FOREIGN PATENTS OR APPLICATIONS 28,675 /1897 Great Britain.......................l37/596 tion 101,673 5/1941 Sweden.................................l37/596 871,799 6/1961 Great Britain B [22] Filed: Nov. 23, 1970 [2]] Appl. No.: 92,018

Primary ExaminerRobert R. Mackey Attorney-Staelin & Overman and Ronald C. Hudgens [52] US. 28/72.l2

ABSTRACT [51] Int. Cl. 1/16 [58] Field of Search............. ..28/l.4, 72.12; 57/34 B;

137/62522 596 Apparatus for and method of texturing yarn at spaced apart regions along its length includin supplying fluid under pressure to a g intermittently yarn texturing noznozzle during time [56] References Cited UNITED STATES PATENTS zle and releasing fluid from the between supply of the fluid.

1/1962 Breen............;.................28/72.l2X 11,550 8/1854 Hatcher...........................137/625.22 7 Claims, Drawing Figures vnpu PATH PATENTEDJAN 16 1975 I 3. 710.461

sum 2 OF 3 f- INVENTORS: I E E GUST/i1! E. BENEU:

.UUUGLAS 5.1 m" TER.

METHOD AND APPARATUS FOR INTERMITTENTLY TEXTURING YARN BACKGROUND OF THE INVENTION Conventional apparatus for producing intermittently textured yarn can not effectively produce such yarn at processing speeds required for economical operations. Speed demands have exhausted the capabilities of the conventional apparatus. As linear yarn speeds increase, intermittent fluid yarn texturing apparatus produces a treated yarn that does not appear significantly different from continuously textured yarn. The yarns textured portions and untextured portions are not easily perceived. In a sense, at high linearyarn speeds, prior apparatus for intermittently texturing yarn with a fluid such as air produces a yarn continuously textured along its length.

While some prior apparatus varies yarn speed traveling through a fluid texturing jet or nozzle to produce intermittently textured yarn, it is difficult to control changes in yarn speed to effect a treatment producing yarn distinctly textured at spaced apart locations or regions along its length. The result is apparatus producing an essentially continuously textured yarn at high yarn speeds.

Other prior apparatus supplies fluid (normally air) from time to time to a yarn texturing jet or nozzle through which yarn travels. A higher linear yarn speeds the individual supplies of air become less distinct in the nozzle; the result is apparatus producing an essentially continuously textured yarn at high yam speeds.

SUMMARY OF THE INVENTION An object of the invention is improved method of and apparatus for producing intermittently textured yarn, especially at high linear yarn speeds.

Another object of the invention is intermittent yarn texturing apparatus that includes means acting at intervals for accelerating fluid escape from within a yarn texturing nozzle to recurrently stop the texturing of yarn traveling through the nozzle.

Yet another object of the invention is apparatus using a fluid yarn texturing nozzle that includes means for intermittently supplying fluid under pressure to the chamber within the nozzle to effect texturing of the yarn leaving the nozzle through an outlet from the chamber common to the fluid and yarn and means acting during interruption of air supply releasing fluid from the chamber to reduce the pressure therein to stop yarn texturing prior to again supplying fluid to the nozzle.

Other objects and advantages will become apparent as the invention is hereinafter described in more detail with reference made to the accompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of apparatus for intennittently texturing multifilament textile material such as glass strand or yarn according to the principles of the invention.

FIG. 2 is an enlarged side elevation view of the yarn texturin g nozzle and fluid regulator arrangement shown in FIG. 1.

FIG. 3 is an end elevation viewof the nozzle and regulator arrangement shown in FIG. 2.

FIG. 4 is a view in cross-section taken along the line 4--4 of FIG. 3. The figure shows a rotary valve positioned to permit a supply of fluid to the texturing nozzle.

FIG. 5 is the cross-sectional view shown in FIG. 4 with the rotary valve positioned to release fluid from within the nozzle.

FIG. 6 is an enlarged side elevation view of an embodiment of a modified yarn texturing nozzle and regulator.

FIG. 7 is a somewhat simplified showing of other apparatus for intermittently texturing yarn according to the principles of the invention.

FIG. 8 is an enlarged side elevation view of the yarn texturing nozzle and fluid regulator arrangement shown in FIG. 7.

FIG. 9 is the yarn texturing nozzle and regulator shown in FIG. 8 modified to include a suction device.

DESCRIPTION OF THE PREFERRED EMBODIMENTS While the apparatus for and method of the invention is especially advantageous in processing continuous or discontinuous filament glass strand, yarn or the like, it may also find advantageous use in processing other multifllament linear strand-like elements of materials such as nylon, rayon, polyester or other organic or inorganic compositions. As indicated, the apparatus of the invention processes twisted or untwisted multifilament linear material. Hence, in the specification and the claims the term yarn includes any textile filament bundle; the bundle can be untwisted, twisted, plied, etc.

FIG. 1 shows apparatus for intermittently texturing yarn. The apparatus advances a single glass yarn 10 from a supply package 12 wound on a bobbin 14 through a fluid yarn texturing jet or nozzle 16. The nozzle 16 is part of a yarn texturing arrangement 17 that effects an intermittent texturing of the advancing glass yarn 10.

A treated yarn 18 leaves the nozzle 16. The .yarn 18 has spaced apart textured portions or regions 20 separated by untextured portions or regions 22.

As shown, a platform 24 supports the bobbin 14.

A platform 26 above the supply package 12 supports a yarn advancing arrangement 28 including a housing 30, a yarn collector 32 for packaging the treated yarn l8 and a liquid sizing applicator 34. The applicator 34 transfers liquid sizing to the traveling treated yarn 18 before the yarn arrives at the collector 32.

The yarn advancing arrangement 28 supplies the glass yarn 10 to the fluid yarn texturing nozzle 16 and also withdraws the treated yarn 18 from the nozzle 16.

The yarn advancing arrangement 28 includes a pair of spaced apart cooperating double diameter feed and take-

up rolls

36 and 38 that mount. on

shafts

40 and 42 respectively. These shafts rotatably mount on the housing 30. An electric motor 44 and a suitable drive arrangement within the housing 30 rotate the

rollers

36 and 38 together in the same direction. As shown in FIG. 1 the rollers move in a clockwise direction. Because it is important that the peripheral speed of each of the

rollers

36 and 38 be the same .at corresponding points on their peripheral surfaces, the rollers are normally identical in size. If the rollers are of different sizes, an operator must modify the drive arrangement to providethe same peripheral speed for each of the rollers.

Assuming that each of the

rollers

36 and 38 have identical dimensions, each of these rollers includes a first cylindrical section 46 having a diameter D' and a second coaxially arranged cylinder section 48 having a diameter d that is smaller in dimension than the diameter D. When the cylindrical sections 46 ofD diameter feed the untextured' glass yarn to the fluid yarn texturing nozzle 16 and the cylindrical sections 48 of d diameter withdraw the treated yarn 18 from the arrangement 17, sections 46 lead the strand to the nozzle 16 at a faster linear speed than the sections 48 withdraw the-treated yarn 18 from the nozzle 16. Accordingly an amount of overfeed is made to the nozzle 16; the ratio of the diameters D/d determines the overfeed.

Referring more particularly to FIGS. 2-5, the fluid yarn texturing arrangement 17 includes the fluid texturing nozzle 16 and a fluid regulator 52. The regulator 52 intermittently supplies fluid,.normally a gas such as air, under pressure to the nozzle 16 to impart spaced apart textured or bulked regions to the speeding yarn advancing through the nozzle 16; the regulator 52 acts during the time between supply of fluid supply to release fluid from with the nozzle 16 to reduce abruptly the pressure in the nozzle to stop yarn texturing before fluid is again supplied to the nozzle.

In the arrangement shown in FIGS. 1 and 2, air is the yarn texturing fluid. A compressor or other suitable means supplies the air.

The apparatus can use any suitable fluid yarn texturing device. As shown, the nozzle 16 includes a cylindrical body 54 having a chamber 56 with an outlet 58 at the forward end of the body 54 for yarn and fluid. In the embodiment, the outlet 58 opens to the atmosphere and is a venturi having a converging entrance 60, a throat 62 and a diverging exit 64. A nipple or needle 66 extends from the rearward end of the body 54 forward through the chamber 56 to terminate in the converging entrance 60 of the outlet 58 short of the throat 62. A passageway 68 extends lengthwise through a nipple 66 from an outer entrance region 70. The inner terminating end of the nipple passageway 68 communicates with the outlet 58; the entrance 70 communicates with the atmosphere.

As indicated in FIG. 2 by the dashed line indicating a yarn path, yarn enters the nozzle 16 at the entrance region 70 of the nipple 66; the yarn speeds through the chamber 56 in the passageway 68. Yarn and air exit the nozzle 16 through the outlet 58. The air escaping the nozzle 16 through the outlet 58 effects or imparts a texturing or bulking to the advancing yarn.

It has been useful to use yarn texturing jet disclosed in U. S. Pat. No. 3,328,863.

The fluid regulator 52 includes a rotary valve 72 with a housing 73 and a variable speed electric motor 74. The valve 72 controls air to the nozzle 16. The valve 72 connects the passageway of a fluid supply line 76 with the chamber 56 of the nozzle 16 by a passageway .78 through the valve 72 and the passageway of an extension tube 80. The tube 80 holds the nozzle 16 on the valve 72. Extending transversely across the passageway 78 in the valve housing 73 is a rotatable shaft 82 that is larger in diameter than the passageway 78 and a valve passageway 84 that proceeds transversely through the shaft 82; the passageway 84 is at right angles to and extends through the axis of rotation of the shaft 82.

The motor 74 rotates the shaft 82 by a belt 86 that connects a sheave 88 on the output shaft of the motor 74 with a sheave 90 on the valve shaft 82. As the motor 74 rotates the shaft 82, the passageway 84 moves into and out of communication with the fluid passageway 78. When the valve passageway 84 communicates with the fluid passageway 78, the valve 72 is open to the nozzle 16; air under pressure in the supply line 76 flows into the chamber 56.

A suitable means such as a compressor fills the supply line 76 with texturing air.

FIG. 4 illustrates the situation where valve passageway 84 communicates with the fluid passageway 78. Therefore the valve 72 is open for supply to the nozzle 16. The arrows in FIG. 4 indicate the direction of air flow during air supply to the nozzle 16.

The regulator 52 includes an arrangement acting during interruption of air supply to the nozzle 16 to abruptly release air from the chamber 56 to the atmosphere for swiftly reducing the pressure in the chamber to stop yarn texturing before again supplying air to the chamber 56. In the embodiment shown there is a fluid exit or exhaust passageway intersecting the supply passageway 78 in the housing 73 of the valve 72; the shaft 82 and passageway 84 are at the intersection. The exhaust passageway includes a first passageway section 92 and a second or exit passageway section 94. The first passageway section 92 communicates with the fluid supply passageway 78 at an entrance region 96 opening onto the passageway 78 between the shaft 82 and the nozzle 16. The other end 98 of the section 92 is at the shaft 82. The shaft 82 separates the first passageway section 92 from the second passageway section 94. The terminating region 98 of the passageway section 92 aligns with the exit passageway section 94. Both

sections

92 and 94 communicate with the valve passageway 84 at the same time as the valve passageway 84 of the rotating shaft 82 aligns itself with the sections.

FIG. 5 illustrates the situation where the valve 82 is open for releasing air from the chamber 56. The passageway 84 communicates with

passageway sections

92 and 94. The arrows indicate the direction of fluid flow during discharge of air from the nozzle 16.

When advancing glass yarn at high speeds, e.g. 3,000 feet per minute, it has been useful to supply air of from 80 to 100 psig to the chamber 56 of the nozzle 16. For these high yarn speeds the apparatus has produced good intermittently textured yarn results when the motor 74 rotates the shaft 82 from 300 to 3,000 rpm s. At these high linear yarn speeds of from 2,000 to 3,000 feet per minute or even higher, it has been possible to produce yarn having textured regions less than 1 foot apart.

A person can vary air pressures and shaft rpm according to the yarn effect desired. Because each revolution of the shaft 82 aligns the valve passageway 84 to communicate twice with the fluid exit passageway (e.g. passageway sections 92 and 94) and fluid passageway 78, each shaft revolution permits two pulses of fluid to the chamber 56 to effect yarn texturing and permits two accelerated releases of fluid from the chamber 56 to stop yarn texturing.

Although it is only necessary to reduce the pressure in the chamber 56 an amount sufficient to stop yarn texturing, in practice the dimensions of the exit passageway and valve passageway 84 release air to reduce the pressure within the chamber 56 to atmospheric or zero gage pressure before the valve 72 supplies air to the chamber 56 again.

While the motor 74 usually rotates the shaft 82 at a continuously varying rpm, it is possible to rotate the shaft 82 at a constant rpm. Accordingly it is understood that a person may operate the apparatus to produce intermittently textured yarn that has recurrent textured regions at periodic spaced apart locations along the length of the yarn or at random or programed spaced apart locations along the length of the yarn.

In the embodiment shown the exit region 98 of the first passageway section 92 and the passageway section 94 extend in a direction generally 90 of the direction the passageway 78. A person can use texturing nozzles with the passageways intersecting at other than right angles. The angle of intersection between the passageways helps determine the location of the textured portions 20 of the yarn 18.

When the yarn advancing arrangement 28 is located with the nozzle 16 as shown in FIG. 1, the yarn l0 travelsabout and between the peripheral surfaces of the larger and first cylindrical sections 46 on each of the feed and take-up

rollers

36 and 38 and thence into the entrance 70 of the yarn texturing nozzle 16. The second cylindrical sections 48 at each of the

rollers

36 and 38 withdraw the treated yarn 18 from the outlet 58 of the nozzle 16. The apparatus locates the second cylindrical section 48 of the roller 38 in relation to the outlet 58 of the nozzle 16 to abruptly remove the treated yarn 18 in a lateral direction from its path through the nozzle 16. The yarn winds around and between the peripheral surfaces of the cylindrical sections 46 and 48 a number of times sufficient to provide enough surface engagement to prevent slippage as the yarn is being feed to and the treated yarn 18 is withdrawn from the nozzle 16. In practice, it has been determined that approximately 4-6 times around and between each of the paths of the

cylindrical sections

46 and 48 is sufficient to prevent yarn slippage.

In most instances it is desirable to partially assist holding the treated yarn 18 in place and further lock the yarn filaments in their respective relationship with one another. Normally itis desirable to employ a fluid sizing applicator such as the liquid sizing applicator unit 34. After the intermittently textured strand 18 leaves the second section 48 of the feed and take-up roller 36, the yarn advances downwardly across a sizing transfer roller 106 of the liquid sizing applicator 34. As the treated yarn 18 travels across the surface of the roller 106, some of the sizing material on the roller surface transfers to the yarn 18.

From the applicator roller 106 the yarn 18 advances to the yarn collector 32. The yarn 18 moves from the roller 106 downwardly to a yarn guide roller 108 that is rotatably mounted on the free end of a pivotally mounted tension sensing arm 110 that comprises part of the yarn collector 32. As illustrated in FIG. 1, the collector 32 is a constant tension take-up device.

Constant tension take-up devices are available through a number of manufacturers and include a ten sion sensing mechanism such as the tension arm that operates electrical-mechanical controls within the device to vary the speed of the yarn package winding on a mandrel in accordance with the variations in the tension in the yarn being wound. As shown the treated yarn 18 advances from the guide roller 108 to be wound as a package 112 on a mandrel 1 14. An electric motor 116 drives the mandrel 114. A yarn traversing mechanism 118 driven by the motor reciprocates the treated yarn 18 in a direction along the length of the package 112 as the advancing yarn l8 winds onto the package 112.

FIG. 6 shows a modified valve 72 indicated by the reference numeral 72'. In the arrangement of the valve 72' the exhaust passageway terminates at its inner end at the chamber 56. As shown an exhaust tube connects the chamber 56 of the nozzle 16 with the valve housing 73 of the valve 72' to complete a first section 92 of an exhaust passageway 91. The first passageway section 92' intersects the passageway 78 at the shaft 82 like the passageway section 92 of the valve 72.

FlG. 7 shows another embodiment of apparatus for intermittently texturing linear multifilament textile material according to the principles of the invention. The apparatus treats two yarns. .As shown, a take-up device 200 advances glass yarn 210 and glass yarn 211 from supply packages 212 and 213, respectively, through a fluid yarn texturing nozzle 216. The nozzle 216 is part of a yarn texturing arrangement 217 that effects an intermittent texturing of the advancing yarns 210 and 21 1.

An intermittently textured two yarn bundle 218 leaves the texturing nozzle 216. The yarn bundle 218 comprises spaced apart textured regions 220 separated by untextured regions 222. At the textured regions 220, the filaments of the

yarns

210 and 211 tangle to combine or to join the yarns. At the untextured regions 222, the

yarns

210 and 211 maintain their individual identity; they are not joined.

Each of the yarns 2-10 and 211 pass across a yarn advancing device along its path to the texturing nozzle 216. As shown, the yarn 210 leaves the package 212 to pass through a pigtail 224 and across a yarn advancing device 226. The device 226 includes two spaced apart driven

rolls

228 and 230. The yarn 211 leaves the package 213 to pass through a pigtail 234 and across a yarn advancing device 236. The advancing device 236 includes two spaced apart driven

rolls

238 and 240.

Referring more particularly to FIG. 8 the fluid yarn texturing arrangement 217 includes the texturing nozzle 216 and a fluid regulator 252 that intermittently pulses air under pressure to the nozzle 216. Air pulsed to the nozzle 216 effects a spaced apart texturing or bulking of the yarn as the yarn and air leave the nozzle; moreover, the regulator 252 acts during times between supply of the air to the nozzle to release air within the nozzle. The air release abruptly reduces the pressure in the nozzle to stop yarn texturing before the regulator again allows air to the nozzle.

The fluid texturing nozzle 216 is like the nozzle 16 shown in FIGS. 1 and 2.

The fluid regulator 252 includes an exhaust valve 270, a rotary supply valve 272 and an electric motor 274. The supply valve 272 is in a supply line 276 that provides air under pressure to the nozzle 216. The valve 272 comprises a shaft 278 and a valve passageway 280. As the shaft 278 rotates, the passageway 280 moves into and out of communication with the supply line 276. When the shaft moves and valve passageway 278 into alignment with the supply tube 276, the valve is open to the nozzle; the passageway 280 allows air to rush to the nozzle 216.

The exhaust valve 270 is on an auxiliary line 281. Line 281 communicates with supply line 276. The exit or exhaust valve 270 also uses a rotary valve comprising a shaft 282 and a valve passageway 284 through the shaft 282. As the shaft 282 rotates, the passageway 284 moves into and out of communication with the auxiliary line 281. When the shaft 282 moves the passageway 284 into alignment with the auxiliary line 281, the valve is open for release of air; the passageway 284 allows air to rush from within the nozzle 216 to escape to the atmosphere.

A motor 274 rotates the

shafts

278 and 282 together by

belts

286 and 288. The belt 286 connects the sheave 289 on the output shaft of the motor 274 with a sheave 290 on the shaft 282 of the exhaust valve 270. The drive belt 288 connects a sheave 289 with a sheave 292 on the shaft 278 of the supply valve 272.

The disposition of the valve passageways'280 and 284 with respect to each other allows only one of the

valves

270 and 272 to be open at any one time. As the motor 274 rotates the

valve shafts

278 and 282, the valves alternate being open. When the supply valve 272 is open, air rushes into the texturing nozzle 216 through the supplying line 276; the exhaust valve 270 is closed. When the supply valve 272 is closed the exhaust valve 270 is open and air speeds from the nozzle 216 to the atmosphere through auxiliary line 281.

In operation the fluid regulator arrangement 217 intermittently supplies air to the fluid texturing nozzle 216; the exhaust valve 270 is closed during air supply. When the supply valve 272 interrupts air to the fluid texturing nozzle 216, the exhaust valve 270 opens to abruptly release air from within the nozzle 216. The release of air swiftly reduces pressure in the texturing nozzle 216 to stop yarn texturing before the supply valve 272 allows air to the nozzle 216 again.

The take-up device 200 withdraws the treated yarn 218 from the texturing nozzle 216 to wind as a package 294. The drive roll 296 engages the periphery of the package 294 to rotate the package. A traversing device 298 reciprocates the advancing yarn 218 axially of the collecting package 294 as the yarn 218 advances to the package.

It is possible, and at times may be advantageous to use a suction device to draw air from a texturing nozzle,

e.g. nozzles

16 and 216. FIG. 9 shows the regulator 252 modified to include a suction device 300 with the exhaust valve 270. The suction device 300 draws air from within the nozzle 216 during the time between supply of air to reduce more rapidly the air pressure within the nozzle 216.

We claim:

1. Apparatus for intermittently texturing yarn comprising:

a body having a chamber therein, the body having an outlet from the chamber through which both yarn and fluid leave the body;

means for linearly advancing yarn from the chamber through the outlet at a speed of at least 1,000 feetper-minute; means for intermittently supplying fluid under pressure to the chamber at sufficiently close intervals to impart a continuous texturing effect to yarn leaving the body through the outlet; and means for increasing the release of fluid from the chamber during time between supply of fluid to reduce pressure sufficiently rapidly within the chamber to stop yarn texturing prior to supply of fluid to the chamber again and thereby impart spaced apart textured regions to yarn. 2. Apparatus of claim 1 in which the means for inter mittently supplying air under pressure to the chamber and the means for releasing air from the chamber during the time between supply of air to reduce pressure within the chamber to stop yarn texturing prior to again supplying air to the chamber comprises a rotary valve and drive means for actuating the rotary valve.

3. Apparatus of claim 1 in which the means for intermittently supplying air under pressure to the chamber and the means for releasing air from the chamber during the time between supply of air to reduce pressure within the chamber to stop yarn texturing prior to again supplying air to the chamber periodically supplies and releases the air.

4. The apparatus of claim 1 in which the outlet is of fixed dimensions.

5. The method of intermittently texturing yarn comprising:

advancing yarn from a chamber through a chamber outlet at a linear speed of at least 1,000 feet-perminute;

intermittently supplying fluid under pressure to the chamber at sufficiently close intervals to impart a continuous texturing effect to the yarn leaving the chamber through the outlet; and releasing fluid from the chamber during time between supply of fluid at a rate greater than release of fluid from the chamber during supply of fluid to accelerate reduction of pressure with the chamber to stop yarn texturing prior to again supplying fluid to the chamber.

6. The method of texturing yarn comprising:

intermittently supplying gas under pressure t0 the chamber at sufficiently close intervals to effect substantially continuous texturing of the yarn leaving the chamber through the outlet; and releasing gas from the chamber during time between supply of gas at a rate greater than release of gas from the chamber during supply of such gas to accelerate reduction of pressure within the chamber to stop yarn texturing prior to again supplying gas to the chamber. 7. The method of pneumatically intermittently texturing yarn comprising:

advancing yarn through a texturing nozzle at a linear yarn speed of at least 1,000 feet-per-minute;

intermittently supplying air under pressure to the texturing nozzle at sufficiently close intervals to effect continuous texturing of the yarn passing through the nozzle; and

Claims

1. Apparatus for intermittently texturing yarn comprising: a body having a chamber therein, the body having an outlet from the chamber through which both yarN and fluid leave the body; means for linearly advancing yarn from the chamber through the outlet at a speed of at least 1,000 feet-per-minute; means for intermittently supplying fluid under pressure to the chamber at sufficiently close intervals to impart a continuous texturing effect to yarn leaving the body through the outlet; and means for increasing the release of fluid from the chamber during time between supply of fluid to reduce pressure sufficiently rapidly within the chamber to stop yarn texturing prior to supply of fluid to the chamber again and thereby impart spaced apart textured regions to yarn.

2. Apparatus of claim 1 in which the means for intermittently supplying air under pressure to the chamber and the means for releasing air from the chamber during the time between supply of air to reduce pressure within the chamber to stop yarn texturing prior to again supplying air to the chamber comprises a rotary valve and drive means for actuating the rotary valve.

4. The apparatus of claim 1 in which the outlet is of fixed dimensions.

5. The method of intermittently texturing yarn comprising: advancing yarn from a chamber through a chamber outlet at a linear speed of at least 1,000 feet-per-minute; intermittently supplying fluid under pressure to the chamber at sufficiently close intervals to impart a continuous texturing effect to the yarn leaving the chamber through the outlet; and releasing fluid from the chamber during time between supply of fluid at a rate greater than release of fluid from the chamber during supply of fluid to accelerate reduction of pressure with the chamber to stop yarn texturing prior to again supplying fluid to the chamber.

6. The method of texturing yarn comprising: advancing yarn from a chamber through a chamber outlet at a linear speed of at least 1,000 feet-per-minute; intermittently supplying gas under pressure tO the chamber at sufficiently close intervals to effect substantially continuous texturing of the yarn leaving the chamber through the outlet; and releasing gas from the chamber during time between supply of gas at a rate greater than release of gas from the chamber during supply of such gas to accelerate reduction of pressure within the chamber to stop yarn texturing prior to again supplying gas to the chamber.

7. The method of pneumatically intermittently texturing yarn comprising: advancing yarn through a texturing nozzle at a linear yarn speed of at least 1,000 feet-per-minute; intermittently supplying air under pressure to the texturing nozzle at sufficiently close intervals to effect continuous texturing of the yarn passing through the nozzle; and releasing air from the nozzle at an increased rate during the time between supply of the air to reduce pressure within the nozzle at a more rapid rate than otherwise released by the nozzle to stop yarn texturing prior to supplying air to the nozzle again.