Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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The present invention relates to apparatus for texturing continuous
filament yarn, and in particular to an apparatus which is efficacious for
crimping continuous filament polyester yarn. This application is a division
of Canadian patent application Serial No. 228,095 filed May 30, 1975.
Several methods of texturing continuous filament polyester yarn
presently are known. The methods which have achieved the widest commercial
success are those in which the yarn is textured by imparting an artificial or
false twist thereto. The quality and uniformity of the textured yarn product
produced by such methods vary widely, and production rates are limited to the
texturing of approximately 200 yards per minute at each texturing station.
The texturing of continuous filament yarns by imparting longitudinal
crimps thereto also has been widely adopted for yarns other than polyester
yarn, and particularly for texturing nylon yarn. However, the prior art meth-
ods of crimping continuous filament yarns and in particular those using a
stuffer crimper apparatus largely have been unsuccessful for crimping poly-
ester yarn. This failure results primarily from the different characteristics
inherent in nylon and polyester yarns. In the stuffer crimping methods pres-
ently used commercially for crimping nylon yarn, a mass of crimped yarn in the
form of a crimped yarn core is fed under pressure through a relatively long
crimping tube in which significant frictional forces are developed between the
outer surface of the core and the walls of the tube. Nylon yarn, due to its
particular characteristics, moves at a substantially uniform ra~e through the
crimping tube, even when subjected to these substantial frictional forces.
However, polyester yarn does not so react under similar conditions, but tends
to move in spurts, resulting in undesirable variations in the characteristics
of the crimped yarn.
The apparatus of the present invention obviates the difficulties
associated with use of the prior art stuffer crimper apparatus for crimping
polyester yarn, and may be used advantageously for crimping other continuous
filament yarns, such as nylon yarn.
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The apparatus of the invention is a stufEer crimper for crimping
continuous filament yarn comprising a first housing member, a crimping chamber
mounted on said first housing member and having a channel extending there-
through, a first feed roll rotatably mounted on said first housing member
adjacent one end of said channel, a second housing member a second feed roll
mounted on said second housing member, mounting means for pivotably attaching
said second housing member to said first housing member so that said second
housing member is movable about a housing pivot axis between a closed position
wherein said second feed roll is adjacent said first feed roll to define a
bite therebetween and an open position wherein said second feed roll is spaced
materially from said first feed roll, and eccentric means for altering the
orientation of said housing pivot axis to thus alter the alignment of said
second feed roll with respect to said first feed roll.
A crimp control roll is preferably spaced from the feed rolls along
a channel a distance no greater than the distance required for the yarn to be
plastically deformed and the crimps partially set in the crimping zone. A
portion of the channel between the crimp control roll and an end of the chamber
opposite the feed rolls defines a setting zone, whereby the core is fed into
the setting zone by the crimp control roll and the crimps are fully set there-
in. The setting zone may comprise a heating portion and a cooling portion.
A yarn core transport belt preferably extends from the crimp control
roll along the length of the heating portion of the setting zone into the cool-
ing portion thereof and has upstanding teeth extending into the channel to en-
gage the yarn mass therein. Further means drive the transport belt indepen-
dently of the feed rolls to transport the yarn mass through the setting zone
at a predetermined rate.
Generally, the leg length of the crimps, and therefore the bulk of
the crimped yarn, is controlled by regulating the pressure applied to the
crimped yarn core in the crimping zone, although other parameters, such as
heat and time of residence in the crimping zone, also affect the characteris-
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tics of the crimped yarn.
The pressure applied to the crimped yarn core is a function of the
relative rotational velocities of the feed rolls and the crimp control roll.
Moreover, it has been found that such pressure also is a function of the rate
at which the crimped yarn core moves through the crimping zone. Generally, as
the rate at which the core moves through the crimping zone is increased for a
particular ratio of feed roll velocity to crimp control roll velocity, the
pressure applied to the core decreases and therefore the bulk of the crimped
yarn also decreases.
In both the crimping and setting zones, the crimped yarn core is
heated to a temperature below the liquefaction temperature of the yarn. The
time of residence of the core in the crimping zone is substantially less than
the time of residence of the core in the setting and cooling zones, and in the
latter two zones the frictional forces applied to the core are minimized.
Due to the heat and pressure applied to the yarn mass during the
process, it is common for deposits to form on the walls of the chamber. For
example, some yarns are coated with a film of oil or a powder applied as a
lubricant during their manufacture, and this lubricant sublimates during the
setting of the yarn to form a sludge deposit on the walls of the setting cham-
ber. These deposits greatly increase the friction between the chamber walls
and the yarn mass, inhibiting the movement of the yarn mass through the setting
zone. The amount of this resistance at any given moment is not predictable.
It can cause the yarn mass to move in spurts, establishing pockets of differing
yarn density during the critical setting operation, thus varying the ya~
crimp characteristics and impairing the uniformity of the finished yarn pro-
duct. It tends to cause the yarn to tear-drop as it moves through the setting
zone, that is, the peripheral portion of the yarn mass lags behind the center
portion, thus disturbing the crimp characteristics. The resistance caused by
these deposits can rise to such a level as to totally stall the movement of
the yarn mass, thus jamming the apparatus and rendering it inoperative. Also,
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the sludge can become abrasive and damage the yarn as it passes through the
setting zone.
In the preferred embodiment of the apparatus of the invention, the
channel in the crimping chamber has a substantially rectangular transverse
cross-section. Desirably, the cross-sectional width of the channel should be
as small as possible. Ideally, it should be approximately equal to the diam-
eter of the yarn. However, both structural and operational factors limit the
minimum cross-sectional width of the channel. For example, for wearing apparel
yarn, i.e., 40-150 denier, the cross-sectional width of the channel must be at
least approximately 0.10 inch.
The preferred embodiment of the apparatus also includes means for
feeding yarn into the nip between the feed rolls with a traversing motion
axially of the feed rolls under controlled tension, and means for controlling
the relative feed and withdrawal rates of yarn into and from the crimper.
Furthermore, the preferred embodiment of the apparatus includes means for en-
gaging the mass of crimped yarn at the exit of the crimping zone and transport-
ing the mass of crimped yarn through the setting zone.
Also, in the preferred embodiment of the apparatus, a relatively
short portion of the channel in the crimping chamber adjacent the feed rolls
has a substantially elliptical transverse cross-section. This feature in com-
bination with the traversing yarn feed to the feed rolls results in the forma-
tion of a uniformily crimped yarn core in the crimping zone.
The preferred embodiment of the apparatus further includes a slug
which rides freely on the top of yarn core in the cooling zone. The slug has
a channel therethrough through which the yarn is withdrawn in continuous fila-
ment form from the cooling zone. The slug also has a particular external con-
figuration which facilitates withdrawal of the yarn in a substantially slub-
free condition.
In order to facilitate the proper alignment of the crimping chamber
with the other elements of the apparatus, in the preferred embodiment the
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crimping chamber is made as a removable unit, and a plurality of alignment
shoulders and surfaces are provided on the machine frame to receive the crimp-
ing chamber unit and position the unit accurately.
The eccentric means for the pivotable housing that holds one of the
feed rolls allows compensation to be made for feedroll skewness and parallelism.
With the foregoing in mind, it is an object of the present invention
to provide an improved apparatus for texturing continuous filament yarn, and
particularly polyester yarn.
It is a further object of the invention to provide an improved appa-
ratus for texturing continuous filament yarn by crimping such yarn.
With the preferred apparatus for crimping continuous filament yarn
disclosed herein, a high degree of crimp uniformity is achieved and the appara-
tus is operable at yarn feed speeds of approximately 1,000 yards per minu~e
per crimping station.
Other advantages and features will become apparent upon a considera-
tion of the detailed description of the preferred embodiment of the apparatus
given in connection with the following drawings, wherein like reference numer-
als identify like elements throughout.
In the drawings:
Figure 1 is a side elevational view of a preferred embodiment of the
stuffer crimper apparatus of the invention;
Figure lA is a perspective view of a detail of the apparatus shown
in Figure l;
Figure 2 is a front elevational view of the apparatus shown in Fig-
ure l;
Figure 3A is a longitudinal sectional view of the lower portion of
the apparatus shown in Figure l;
Figure 3B is a longitudinal sectional view of the upper portion of
the apparatus shown in Figure l;
Figure 4 is a sectional view taken on line 4-4 of Figure 3A;
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Figure 5 is a sectional view taken on line 5-5 of Figure 3A;
Figure 6 is a sectional view taken on line 6-6 of Figure 3A;
Figure 7 which appears on the same sheet as Figure 3A, is a longi-
tudinal sectional view of crimping zone portion of the apparatus shown in Fig-
ure 3A;
Figure 8 which also appears on the same sheet as Figure 3A, is a
front elevational view of a portion of the feed roll saddle of the apparatus
shown in Figure 7;
Figure 9 which is on the same sheet as Figures 7 and 8, is a top
plan view of the feed roll saddle taken on line 9-9 of Figure 8;
Figure 10, which is on the same sheet as Figures 7 to 9, is a sec-
tional view taken on line 10-10 of Figure 7;
Figure 11 which is on the same sheet as Figure 2, is a front eleva-
tion view partially in section of the lower portion of the apparatus shown in
Figure 1, with some elements removed for clarity;
Figure 12 is a sectional view taken on line 12-12 of Figure 11;
Figure 13 is a rear elevational view of a portion of the apparatus
shown in Figure 1, taken along line 13-13 of Figure 12;
Figure 14 which is one the same sheet as Figure 6, is a sectional
view taken on line 14-14 of Figure 13;
Figure 15, which is on the same sheet as Figure 6, as a perspective
view of one type of yarn core transport belt that can be employed in the appa-
ratus shown in Figure l;
Figure 16, which is on the same sheet as Figure 6, is a perspective
view of an alternate type of yarn core transport belt that can be employed in
the apparatus shown in Figure l;
Figure 17 is a rear elevational view of the upper portion of the
apparatus shown in Figure l;
Figure 18 is a sectional view of a portion of the apparatus shown in
Figure 17;
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Figure 19 is a perspective view of the slug employed in the appara-
tus shown in Figure l;
Figure 20 is a sectional view taken on line 20-20 of Figure 18;
Figure 21 is a plan view of the electrical circuitry of the yarn
core height sensing and control means of the apparatus shown in Figure l;
Figure 22 is a sectiona view taken on line 22-22 of Figure 3B;
Figure 23 is a sectional view taken on line 23-23 of Figure 17;
Figure 24 is a front sectional view of the eccentric mounting means
for the yoke which carries the movable feed roll of the apparatus shown in
Figure 1, taken along the line 24-24 of Figure 25;
Figure 25 is a side elevational view of a portion of the mounting
shown in Figure 24;
Figure 26 is a side elevational view of the pivot center of the
mounting shown in Figure 24;
Figure 27 is a side elevational view of the opposite side of the
pivot center shown in Figure 26;
Figures 28, 29 and 30 are top, front and side views, respectively,
of feed roll alignment test set-up; and
Figure 31 is a sectional view of the crimp control rolls and a por-
tion of the yarn transport belt of the apparatus shown in Figure 1.
A preferred embodiment of the apparatus of the invention is a stuffer
crimper designated generally by reference numeral 10. Crimper 10 includes a
rear stationary housing member 12 which is secured to a frame 14 by bolts 16,
or other suitable fasteners. A front housing member 18 is pivotally connected
to rear housing member 12 by an eccentric mounting indicated generally as 20
and explained in detail below.
Mounted between housing members 12 and 18 is a crimping chamber 26
comprising front and rear longitudinally mated halves 28 and 30, respectively
~Figures 3A and 12) and a pair of laterally spaced bars 32 interposed there-
between. Bars 32 extend upwardly the full length of the apparatus. Chamber
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halves 28 and 30 are made from a metallic material, and are secured together
by a plurality of bolts 34. Bars 32 are made from a metallic material having
a relatively low heat conductivity, such as 302 stainless steel, so that the
heat from the crimping and setting zones is not transmitted by bars 32 into
the cooling zone. Assembled chamber 26 is secured to reaT housing member 12
by a plurality of bolts 35, or other suitable fasteners. Bolts 35 are insert-
ed through openings in Ghamber halves 28 and 30 (Figure 12) which have a
slightly larger diameter than the bolts so that chamber 26 is sligh~ly movable
and can be properly aligned with the other elements, as explained below.
Chamber halves 28 and 30 and bars 32 define respectively the front, back and
sides of substantially the entire length of a channel 36. Friction reducing
inserts 33 are provided to line the front and rear of channel 36. A short
portion of channel 36 at the lower end thereof has a generally elliptical
transverse cross-section not defined by bars 32, (Figure 9) and the remaining
portion of the channel has a substantially rectangular transverse cross sec-
tion (Figure 10).
Alignment of crimping chamber 26 with respect to the other com-
ponents of the apparatus is critical. To facilitate this alignment, rear
housing member 12 is provided with first and second sets of bosses 40 and 42.
Each boss 40 has a rear alignment surface 44 and a side alignment surface 46.
Each boss 42 has a rear alignment surface 48. The rear surface 50 and the side
surface 52 of the chamber half 30 are smoothly and accurately machined, as are
surfaces 42, 46 and 48. To install chamber 26 upon rear housing 12, surface
50 is placed into contact with alignment surface 44, and surface 52 in contact
with side alignment surface 46. Screws 35 are installed but not tightened.
Chamber 26 is then moved longitudinally until its proper relationship with
the other components is achieved. Then chamber 26 is locked against lateral
movement by tightening down upon it a pair of locking screws 56 threaded
through rear housing 12 and contacting side surface 58 of chamber 26, which
forces chamber alignment surface 52 to seat against side alignment
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surfaces 46. Screws 35 are then tightened, seating rear surface 50
against rear alignment surfaces 44 and 48.
A pair of opposed feed rolls 68 and 70 are journalled in housing
members 18 and 12, respectively, adjacent the lower end of chamber 26.
In their operating positions, feed rolls 68 and 70 define a nip between.
Positioned at the lower end of chamber 26 is a saddle 72, which fits
closely about the peripheries of feed rolls 68 and 70, from slightly
below to slightly above the nip (Figure 3A~. Saddle 72 is attached to
rear chamber half 30 by bolts 73. A first pair of arcuate surfaces 74
and 76 of saddle 72 fit closely about the circumferential peripheries
of rolls 68 and 70. A second set of arcuate surfaces 78 and 80 of
saddle 72 fit closely about the axial peripheries of a pair of crimp
control rolls 122 and 124. A shim 79 can be interposed between saddle
72 and chamber half 30, if necessary. A felt pad 75 (Figure 3A~ is
mounted at the upper end of each of arcuate surfaces 74 and 76 and
extends outwardly therefrom into contact with the associated rolls 68
and 70, so that yarn cannot migrate outwardly between the arcuate
surfaces and the feed rolls.
Chamber halves 26 and 28 are provided with a pair of elongated
bores 71 and 73, respectively, into which are inserted a pair of electrical
heating elements 79 and 81. Bores 71 and 73 are parallel to channel 36,
and are closed at their lower ends by pins 82, upon which rest heating
elements 79 and 81. A temperature sensing element 83 is positioned in
the lower portion of chamber half 30 to sample the temperature in the
chamber. Another heating element 84 can be installed in a bore in the
lower portion of chamber half 30, held in place by a set screw 85.
Feed rolls 68 and 70 are machined as integral portions of
shafts 86 and 88 (Figure 5). Shaft 86 is journalled in bearings 90
mounted in front housing member 18, and shaft 88 is journalled in bear-
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ings 92 mounted in rear housing member 12. The outer races of bearings 90
are accommodated in recesses 96 machined in front housing member 18. Bearings
90 are locked in position by bearing retainers 98, which are secured to
housing member 18 by bolts 102 (Figure 1). Similarly, the outer races of
bearings 92 are accommodated in recesses 104 formed in rear housing member
12, and are locked in position therein by bearing retainers 106. Retainers
106 are secured to housing member 12 by bolts 108 (Figure 1).
A gear 110 is affixed to one end of shaft 86 and a similar
gear 112 is affixed to the same end of shaft 88. A pulley 114 is affixed
to the other end of shaft 88. The ends of shafts 86 and 88 are threaded
and the shafts are axially locked in position with respect to bearings 90
and 92 by nuts 118 and spacers 120.
A pair of opposed crimp control rolls 122 and 124 also are
journalled in housing members 18 and 12, respectively, about axes parallel
to the axes of feed rolls 68 and 70. In the preferred embodiment of the
apparatus of the invention, crimp control roll portions of roll 122 and 124
have textured surfaces formed by gear-like teeth- Roll 122 is machined as
an integral portion of shaft 126 (Figure 6~. Crimp control rolls 122 and
124 are accommodated within arcuate openings machined in chamber halves
28 and 30, respectively. The peripheries of crimp control rolls 122 and
124 are spaced apart, but protrude into channel 36, to define a yarn
control passage of fixed width designated by reference numeral 130. Shaft
126 is journalled in bushings 132 which are accommodated in recesses 134
machined in front housing member 18. Similarly, shaft 128 is journalled
in bushings 136 which are accommodated in recess 138 machined in rear housing
member 12.
A gear 142 is affixed to one end of shaft 126 and a similar
gear 144 is affixed to the same end of the shaft 128 (Figure 6). A pulley
146 is affixed to the same end of shaft 128 as gear 144, outwardly of the
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gear. Shafts 126 and 128 are axially locked in position with respect to
bushings 132 and 136 by spring clips 147 and clamps 148.
Crimp control roll 122 is continuous across the entire width
of channel 36. However, crimp control roll 124 is split into a pair of
toothed sections 150 and 152 flanking a central yarn transport belt pulley
section 154. Gear sections 150 and 152 and pulley 154 are mounted on a
shaft 128 which has a square section at its mid-portion as at 129 (See
Figure 3A).
When front housing member 18 is in the operating position shown
in solid lines in FIW RE 1, gear 110 meshes with gear 112 and gear 142
meshes with gear 144. Also, the circumferential periphery of feed roll
68 contacts the circumferential periphery of eed roll 70, forming a nip
therebetween. The teeth of gears 110, 112, 142 and 144 are elongated suf-
ficiently to insure that the gears will mesh properly when the feed rolls
are in contact with each other.
Crimper 10 also includes means for urging front housing member
18 rearward toward rear housing member 12. Such means include a split
frame 160 (Figures 1 and 2) which is affixed to front housing member 18
by bolts 162, or other suitable fasteners. Frame 160 extends downwardly
and inwardly from the lower end of housing member 18. A handle 164 (Figure
lA) is removably connected to the lower end thereof.
A flexible cable 166 extends through the back of handle 164
and is slidably connected thereto by a disc 168 fixed to the end of the cable
(Figure lA). Cable 166 passes around a pulley 170 and a weight 172 is affixed
to the other end thereof. Pulley 170 is mounted on a shaft 174 which is
journalled in a pair of arms 178 mounted on frame 14.
Affixed to the lower end of frame 160 are a pair of horizontally
aligned pins 180 which are adapted to register with a pair of openings 182
in the back of handle 164. When pins 180 are engaged with openings 182,
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weight 172, via cable 166, pulls frame 160 and front housing member 18
rearwardly toward rear housing member 12. Thereby, the circumferential
peripheries of feed rolls 68 and 70 are urged together.
When it is desired to pivot front housing member 18 away from
rear housing member 12, as shown in broken lines in FIGURE 1, handle 164
is pulled outwardly so that pins 180 disengage from openings 182, and
thus frame 160 is released. For convenience, a pair of pins 186 similar to
pins 180 are affixed to frame 14 and are adapted to register with openings 182
to hold handle 164 against the frame in the position shown in broken lines
when front housing member 18 is pivoted away from rear housing member 12.
Crimper 10 further includes means mounted below feed rolls 68
and 70 for feeding yarn to the nip between the feed rolls. The yarn feeding
means includes a split cam 190 (FIGURES 3A and 4). Cam 190 comprises a
pair of axially opposed, cylindrical yarn guiding members 192 and 194 which
are affixed, respectively, to a pair of circular flanges 196 and 198.
Flanges 196 and 198 are mounted on a shaft 200 having an enlarged cylindrical
central portion 202. Flanges 196 and 198 accommodate the ends of the enlarged
portion 202, and are connected together by a plurality of circumferentially
spaced bolts 204 passing through a hub 206. The ends of bolts 204 are
threaded and receive nuts 210 thereon which lock flanges 196 and 198 onto
shaft 202. Yarn guiding members 192 and 194 ~efine a helical slot 212
(Figure 4~ therebetween through which yarn is fed to feed rolls 68 and 70
as described below. Flanges 196 and 198 are provided with a plurality
of opposed openings 214 and 216 which accommodate a plurality of yarn
support rods 218, which are cemented in place at one end with resiliant
cement 220 set in openings 216. This allows relatively easy replacement
of rods 218, which are subject to wear, as well as some flexibility to
loading. Yarn support rods 218 limit the depth to which the yarn penetrates
helical slot 212.
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Shaft 200 is journalled about an axis parallel to the axes
of feed rolls 68 and 70 in bearings 224, which are accommodated in recesses
226 in a pair of arms 228 integral with frame 12. Bearings 224 are locked
in position by retainers 230 which are secured to arms 228 by bolts 232.
Also mounted on shaft 200 is a pulley 236. A pair of nuts 238 are threaded
onto the ends of shaft 200, and spacers 240 are interposed bet~een bearings 224,
pulley 236 and nuts 238.
A pair of pulleys 242 and 244 (Figure 1~ are mounted on a shaft
246 which is journalled about an axis parallel to the axes of feed rolls
68 and 70 in bushings 248. Bushings 248 are accommodated in a pair of arms
250 (only one of which is shown) affixed to frame 14, and are locked in
position by retainers 252 which are secured to arms 250 by bolts 254.
Another pulley 256 is mounted on a shaft 258 attached to rear stationary
housing 12.
A first belt 260 is ~rained about pulleys 114, 242 and 256.
The back side of belt 260 also engages pulley 236. Thereby, yarn feed
rolls 68 and 70 are driven in synchronism with yarn traverse cam 190. A second
belt 262 is trained about pulley 244 and another pulley (not shown) con-
nected to an appropriate driving means (also not shown), such as an electric
motor, for driving feed rolls 68 and 70 and cam 190.
A third belt 264 is trained about pulley 146 and still another
pulley 266 which is attached to the output shaft of a transmission 268.
An electric motor (not shown) is drivingly connected to transmission 268
for rotating crimp control rolls 122 and 124 independently of feed rolls
68 and 70. Appropriate openings are provided in frame 14 to permit the
passage of cable 166 2nd belts 260 and 264 therethrough.
Crimper 10 further includes a cooling tower 270 (Figures.
1~ 2, 3B and 17~ affixed to the upper end of crimping chamber 26. Bars
32 extend through the entire cooling tower 270. Tower 270 comprises a
rear member 272 and a front member 274. Front member 274 is formed of sheet
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material and has a U-shaped cross-section that encompasses bars 32. Members
272 and 274 are longitudinally mated and together define a channel 278
that is a continuation of channel 36. Members 27Z and 274 are connected
together by bolts 280, which also pass through openings in bars 32, thus
attaching cooling tower 270 to the top of crimping chamber 26. Several
longitudinally extending traverse openings 282 are formed in the side of
member 274 to permit a coolant, such as compressed air, to contact the yarn.
A yarn exit guide 286 is mounted on a flange 288 formed as a part of
member 274. Members 272 and 274 are spaced slightly from the top of chamber
26 by an air gap 289, to preclude transfer of heat from chamber 26 to the
cooling tower.
A slug 300 (Figure 19) rides freely in the upper end of channel
278 on the top of the core of crimped yarn contained therein. Slug 300
has an upper parallelepiped shaped portion 302 and a lower generally pyramidal
shaped portion 304. Lower portion 304 includes a pair of leg-like members
306 and 308 which extend downwardly and outwardly at opposite sides thereof.
A channel 310 having a generally rectangularly shaped transverse cross-section
extends longitudinally through slug 300. A small permanent magnet 312 is
mounted in a transverse groove 314 formed in one side of upper portion 302,
for the purpose of operating a set of crimper control switches, described
below. Slug 300 is guided in its vertical movements by bars 32. Since
the upper parallelepiped shaped portion 302 is smaller than the lower portion
304, the slug can rock slightly so that legs 306 and 308 always contact yarn
core 510.
A printed circuit board 320 ~See Figure 3B) is mounted on the
side of member 272 adjacent the upper end thereof. A plurality of bolts
322 extend through board 320 and are threaded into member 272. Mounted
on board 320 are five vertically spaced, magnetically sensitive switches
328, 330, 332, 334 and 336.
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Member 272 has a longitudinally extending transverse recess
340 to accommodate switches 328-336. As slug 300 moves vertically upwardly
and downwardly with the upper end of the core of crimped yarn, magnet 312
moves into and out of proximity with switches 328-336, and selectively
closes and opens the switches. Electrical leads 340, 342, 344, 346 and 348
connect switches 326, 328, 330, 332, 334 and 336 respectively, to various
electrical circuits to control the operation of crimper 10, as described
below.
In addition to the means for alignment of crimping chamber 26
upon installation on rear stationary member 12, means are also provided
for precise alignment of feed rolls 68 and 70 with respect to one another.
Feed roll 68 is mounted on rear stationary member 12, while feed roll 70
is mounted on front housing 18, which is pivotally attached to rear stationary
- housing 12 by an eccentric mounting structure broadly designated by the
numeral 20. This structure is shown in detail in Figures. 24-27. Rear
housing 12 is provided with a pair of spaced outwardly extending mounting
ears 350 and 352, having bores 354 and 356, respectively. A slit 358
extends outwardly from each of the bores 354 and 356, and clamping screws
360 extend through openings 362 into threaded holes 364.
A pivot center 364 in the form of a cylindrical plug is accom-
modated in bore 354. Attached to the outer surface of pivot center 364,
on the center axis 366 thereof, is an adjustment lug 368, which can be
engaged by a wrench or the like to rotate pivot center 364. On its inner
surface 370, pivot center 364 is provided with a cone-shaped recess 372, the
apex 374 of which is located offset from center axis 366, as shown in Figures
26 and 27. A cover plate 376 attached to arm 350 by screws 378 holds pivot
center 364 against outward movement.
Likewise, a second pivot center 380 is installed in bore 356.
An adjustment lug 382 is attached to the outside of pivot center, and a
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cone-shaped recess 384 is provided on inside surface 386. The apex 388
of recess 384 is offset from center axis 390 of pivot center 380. A pivot
center cover 392 is attached to arm 352 by screws 394 to hold pivot center
380 against outward movement.
The upper portion of front housing member 18 is provided on its
sides 400 and 402 with a pair of cone-shaped recesses 404 and 406, the
apexes 408 and 410 of which are aligned on a pivot axis 412. A pair of hard
metal balls 414 and 416 are interposed between front housing member 18
and arms 360 and 352, seated in recesses 372 and 404, and 384 and 406,
respectively. Balls 414 and 416 are tightly seated in the cone-shaped
recesses. The diameters of the balls are selected to provide gaps 418
and 420 between front housing member 18 and arms 350 and 352.
Two degrees of alignment are necessary between feed rolls 68
and 70. Shown in Figures. 28 and 29 is a test set-up to accomplish this.
A pair of elongated test fixtures X and Y are installed on the crimper in
place of the feed rolls, to accentuate any misalignment. For purposes of
explanation, pivot center 364 has been designated the feed roll parallelism
adjustment, auld pivot center 380 the feed roll skew adjustment. If it is
found, upon placing front housing member 18 in the operating posi~ion, that
the surfaces of test fixtures X and Y are not parallel to one another in
vertical planes, that is, looking down from the top, pivot center 364 is
rotated, and thus offset ball 414 describes an arcuate movement. This
causes the upper portion of front housing member 18 to move about the fixed
ball 416 and results in compound arcuate movement by the lower portion of
housing member 18 and, of course, of test fixture Y. By suitable manipula-
tion, the feed roll parallelism is established. Likewise, if one test
fixture is skewed with respect to the other, that is, not parallel along
the bite when looking from the front of the crimper, pivot center 380 is
rotated. This causes offset ball 416 to describe an arc, and front housing
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member 18 to move about stationary ball 414. In actual practice, the
combination of the two eccentrically mounted balls allows precise adjustment
of the ~eed rolls necessary for the proper operation of the stuffer
crimper. Once alignment is completed, bolts 360 are tightened to clamp
pivot centers 364 and 380 securely in this adjusted position. Test fixtures
are then removed, and feed rolls 68 and 70 installed.
In order for the crimper 10 properly to operate, the axes of
the various roll shafts must accurately be aligned with the longitudinal
axis of channel 38, to which the side surface 50 and rear surface 52 of
chamber 26 are aligned. Rear alignment surfaces 44 and 48 of bosses 40
and 42 and side alignment surfaces 46 of bosses 40 are accurately machined
so that crimping chamber 26 is properly positioned. A longitudinal alignment
axis 384 is established through side alignment surfaces 46, and the various
bearing recesses, the bearings themselves, and the shafts mounted in the
bearings, are oriented to the axis 384 (Figure 11). Crimp control roll
axis 386, feed roll axis 388, and traverse cam axis 390 are perpendicular
to alignment axis 384. Crimping chamber 26 is automatically aligned when
it is installed, since it abuts side alignment surfaces 46.
As explained above, prior art crimpers have experienced
20 considerable difficulties in moving the core of crimped yarn through chamber
36 to the cooling tower 270. To overcome these problems, the crimper
of this invention is provided with a novel yarn core transport mechanism.
A driven endless belt 400 engages the mass (or core) of crimped yarn to
positively transport it through the setting chamber into the cooling tower.
Transport belt 400 is uniquely interrelated with crimp control rolls 122
and 124, and together they inswre that the mass of crimped yarn is of proper
density, and that this density is maintained uniform as the yarn moves
through the setting process. The transport belt moves the yarn core at
the desired speedO Transport belt 400 can be in the form of reinforced
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15~5'~55Z
fabric material, metal tape, rubber or the like. It is the function of
transport belt 400 positively to engage the mass of crimped yarn, and there-
fore a plurality of spaced engaging elements are provided. In the case of
a fabric belt, this can be in the form of upstanding gripping elements or
pins 402 woven into or secured to belt 400 (Figure 15), or a plurality of
spaced upstanding silicone rubber teeth 404 (Figure 16).
Belt 400 passes around belt pulley portion 154 of crimp control
roll 124, and then passes upwardly through channel 36 and through the lower
portion of channel 278. The back surface of belt 400 contacts the chamber
liner 33. Belt 400 then travels around an adjustable idler pulley 414
mounted on a bearing 416, which is in turn supported on a shaft 418 (See
Figure 22). Shaft 418 has a head portion 420 and a threaded portion 422
that is screwed into an idler arm 424. Idler arm 424 is pivotally supported
by a rod 430 mounted in openings 432 in rear cooling tower element 272.
Rod 430 has a peripheral groove 434 at one end which is engaged by a locking
screw 436 in rear tower element 272. A spacer 438 separates idler arm
424 from member 272. Idler arm 424 is mounted in such a position as to
place the outer surface of idler pulley 414 at an opening 440 in the rear
wall of chamber 278, spaced slightly outwardly of the said rear wall to
receive belt 400.
Pivotable idler arm 424 provides the means for adjusting the
tension on belt 400. A shoulder 442 extends inwardly from rear tower member
272 beneath idler arm 424. A threaded plug 444 is screwed into a threaded
opening in shoulder 442 and secured with a lock nut 445. Plug 444 is
provided with an axial bore having an internally threaded portion 446,
a smooth-walled middle portion 448 and a smooth-walled end portion 450 of
lesser diameter than portion 448. A pin 452 having a rounded end 454 and a
flanged portion 456 is received in bore portions 448 and 450, with head
454 protruding from plug 444. A helical coil spring 458 is contained in
_ 18 -
105;~55Z
middle portion 448. An adjustment screw 460 is screwed into threaded
portion 446, and bears against one end of spring 458, the other end of
which bears against pin 452. The rounded head 454 contacts the underside
of idler arm 424 (Figure 22) and urges idler arm 4~4 upwardly to tension
belt 400 in accordance with the pressure placed on spring 458 by screw 460.
Finally, belt 400 proceeds downwardly to another idler pulley 464
mounted on a bearing 466 supported by a shaft 468 mounted in a slot 469
in the rear bottom end of chamber member 30. A belt cover 470 is attached
to the rear of chamber member 30 by screws 472, as shown in Figure 14.
There is a particularly critical r~lationship between belt 400
and crimp control roll 124. The function of crimp control rolls 122 and
124 is to feed the crimped yarn at a controlled rate from the crimping
zone beneath the crimp control rolls to the setting zone above the crimp
control rolls. It is important that the characteristics of the core of
crimped yarn, such as the density and homogeneity, be maintained constant
throughout the yarn setting operation, or else the crimp characteristics
can be disturbed, which results in an imperfect yarn. The yarn core
enters the setting zone at a particular linear speed, imparted by the
crimp control rolls, as applied to the yarn core at a particular point
on the teeth which can be labeled the effective diameter. Since the
teeth embed themselves into the yarn core, the effective diameter is
measured at a point on the teeth short of the tips, and is thus somewhat
less than the full outside diameter of the teeth. The linear speed of
the yarn transport belt is matched to the linear speed of the gear at
the point of the effective diameter. Looking to Figure 31, it is
seen that teeth 474 subscribe a radius 476. However, the effective
linear speed imparted by the gears is measured at a lesser radius 478.
The radius 480 of belt pulley 154 is selected so that the speed of the
transport belt matches the effective peripheral speed of the crimp control
-- 19 --
~5'~5~2
rolls. Thereby, there is no change in the speed of movement of the yarn
core as it passes from the influence of the crimp control rolls to that
of the transport belt. It has been found to be advantageous to have the
length of pins 402 slightly greater than the length of the crimp control
roll teeth.
Alternatively crimp control roll 124 could be devoid of teeth,
functioning only as a pulley for a somewhat wider belt. Then, the belt
could also function as the second of the pair of crimp control rolls.
The method of operation will now be described in detail with
reference to crimper 10. Continuous filament yarn 500 is fed from a spool
of such yarn or other source of yarn supply through a conventional tension
control mechanism 502 (Figure 1) upwardly into slot 212 of cam 190. Slot
212 guides the yarn into the nip between feed rolls 68 and 70 with a
traversing movement back and forth axially of the feed rolls. As the yarn
passes through cam 190, it contacts rods 218. Rods 218 and the edges of
cam portions 192 and 194 which define slot 212 are polished so that friction
is minimized. In order to obtain uniform feeding of the yarn into the nip,
both with respect to yarn quantity and orientation, it is necessary that
tension of a controlled magnitude be applied to the yarn between mechanism
502 and feed rolls 68 and 70.
A conventional preheater 504 may be interposed between mechanism
502 and cam 190 to preheat yarn 500 prior to the crimping thereof.
Generally, it has been found desirable to preheat yarn which is heavier
than two denier per filament. Preheating softens the yarn and facilitates
the crimping thereof.
Immediately after passage between feed rolls 68 and 70, the
yarn is fed against a mass of crimped yarn in the form of a core of crimped
yarn 510 (Figure 3A) in the lower end of channel 36, causing the yarn to
collapse longitudinally and fold over, forming crimps which become part
-- 20 --
lOS'~55'~
of the core. The generally elliptical transverse cross~sectional configura
tion of the lower portion of channel 36 minimizes voids in the channel
in the zone immediately above the feed rolls so that a substantially
uniform crimping pressure will be applied to the yarn after it passes between
the feed rolls. The portion of channel 36 between feed rolls 68 and 70
and crimp control rolls 122 and 124 comprises a crimping zone. The crimp
control rolls effectively isolate the crimping zone from the portion of
channel 36 thereabove. By controlling the relative rotational velocities
of the feed rolls and the crimp control rolls, the back pressure or crimping
force exerted on the yarn in the crimping zone may be accurately established
and controlled. Generally, for a yarn of a particular denier, an increase
in the crimping force results in a decrease in the leg length of the crimps
and an increase in the buIk of the crimped yarn. The crimping force may
be increased by decreasing the rotational velocity of crimp control rolls
122 and 124 with respect to the rotational velocity of feed rolls 68 and 70.
The yarn is crimped and plastically deformed in the crimping zone. However~
the heat and pressure applied to core 510 and the time of residence of the
core in the crimping zone is insufficient to cause the yarn to be set
permanently, and in the absence of pressure on the core the crimps will
open freely after passage through the crimping zone. Moreover, for
polyester yarn, it is desirable that the residence time of the yarn in the
crimping zone be relatively short to minimize the effects of friction on
the formation of the crimps~ and therefore, the distance between feed
rolls 68 and 70 and crimp control rolls 122 and 124 along channel 36 is
relatively short. This arrangement facilitates accurate control of the
conditions within the crimping zone, with the frictional forces exerted
on the yarn by the walls of channel 36 in the crimping zone having little
or no effect on such conditions.
Also, desirably the cross-sectional dimension of channel 36
lOS'~S52
in the direction perpendicular to the axes of feed rolls 68 and 70, i.e.
the cross-sectional width of the channel, should be as small as possible
to promote uniform heat transfer from chamber 26 to and through core 510.
Ideally, the cross-sectional width of channel 36 should be approximately
equal to the diameter of yarn 500. However, at least two factors limit
the minimum cross-sectional width of the channel. First, as the cross-
sectional width of the channel is decreased, the angle defined between
each of the side walls of the channel which extend in the direction parallel
to the feed roll axes and respective arcuate surfaces 74 and 76 also is
decreased (Figure 3A). If such angle is made too small, the adjacent portion
of saddle 72 does not possess sufficient strength to withstand the pressure
exerted thereagainst by core 510 without deforming or fracturing. Second,
as such angle is decreased, the apex thereof necessarily is moved downwardly
closer to the nip between feed rolls 68 and 70. If the apex of the angle
is moved too close to the nip between the feed rolls, as yarn 500 is fed
through the nip, the yarn will tend to move under surfaces 74 and 76
between such surfaces and feed rolls 68 and 70 rather than into channel
36, regardless of the presence of felt pads 82, whose purpose is to prevent
yarn 500 from moving out of the crimper between feed rolls 68 and 70
and arcuate surfaces 74 and 76. This is particularly necessary during
start-up of the crimper, before core 510 fills the crimping zone.
It has also been found that the cross-sectional width of chan-
nel 36 in relation to the cross-sectional area of yarn 500 has an important
effect on the operation of the crimper. For example, for wearing apparel
yarn, i-e-, 40-150 denier, the ratio of cross-sectional width of the
channel in inches to the yarn denier should be in the range from about
o.ooo667 to about 0.00425; the cross-sectional area of the yarn being
proportional to the denier thereof. Preferably, such ratio is in the
range of from about .001 to about .oo4. If the cross-sectional width of
- 22 -
1~5;~5S~ -
channel 36 is reduced below an amount required to satisfy the above-mentioned
range of values for such ratio, the Yarn will tend to move under surfaces
74 and 76 between such surfaces and feed rolls 68 and 70. For yarn
having a denier in the range of 40-150, the cross-sectional width of the
channel should be in the range of from about 0.10 inch to about 0.17
inch, and preferably is about 0.16 inch.
Crimp control rolls 122 and 124 engage and feed core 510 upwardly
out of the crimping zone to the setting zone, which extends between crimp
control rolls 122 and 124 and the upper end of chamber 26. In the setting
zone, the core is subjected to heat and pressure sufficient only to keep
the crimps that were formed in the crimping zone closed. The only
pressure exerted on the core in the setting zone is the weight of the core
itself and the relatively light weight of slug 300 which rides on the upper
end thereof. In the setting zone, the yarn is fully set.
The heat and pressure to which the yarn is subjected in the
crimping zone, and the heat of the setting zone, cause deposits ~o form on
the walls of channel 36 in the setting zone. These deposits are often
emulsions formed from the lubricating oil present in the yarn. The deposits
are of gum-like consistancy, and scrape against the outer surface of yarn~
core 510, causing physical damage to the yarn, a tear-drop effect on yarn
core movement, and uncontrollable and varying back pressures upon the
yarn core. The result is a yarn having unpredictable and undesirable
crimp characteristics, as well as physical damage. In some cases, the
retardation of the movement of the yarn core is so severe that the moving
yarn core is turned into a stationary wad of yarn, that JamS the machine.
The use of low friction inserts 33 in channel 36 somewhat
reduces the problem of deposits, but not to acceptable levels. However,
yarn transport belt 400 does solve the problem. It positively engages
yarn core 510 at the point at which it passes from the influence of crimp
l()S;~S52
control rolls 122 and 124. Belt 400 positively grips the core 510, by means
of pins 402. It moves the core through the setting zone and into cooling
tower 270 at the same linear speed imparted by the crimp control rolls.
This overcomes the increased resistance to movement caused by the deposits,
and in fact tends to clean the channel walls. The yarn core does not slow
down or move jerkily, and uniform density is maintained because the core
is engaged by the belt along its entire length.
After passing through the setting zone, core 510 is transported
into channel 278 of coo'ing tower 270, at which time the yarn is cooled
below the temperature at which it undergoes any m~cular structural altera-
tion in the absence of the application of a substantial force thereto.
If desired, and depending upon the necessity therefore, a coolant, such as
compressed air, may be introduced into and circulated through the core
through openings 282. The crimped yarn is withdrawn from channel 278
through channel 310 through slug 300 in continuous filament form by a
conventional winder 512 on which it is wound into cones for further pro-
cessing, as desired~
The external configuration and dimensions of slug 300 are
important to smooth, substantially slub-free withdrawal of the yarn from
20 cooling tower 270. The only portions of the slug which contact the upper
end of core 510 are leg-like members 306 and 308 (Figure 19). The portions
of the core contacted by members 306 and 308 are positioned adjacent the
short cross-sectional transverse dimension of channel 278 and are the
portions in which the yarn feed direction, a~ially of the feed rolls, is
reversed by cam 190. Members 306 and 308 apply a slight pressure~ namely
the weight of slug 300, on such portions and thereby require that a relatively
small increase in tension be applied to the yarn to pull it out from under
the members. The application of this increased tension pulls substantially
all of the tangles out of the yarn and thereby minimi~es the occurance of
- 24 -
~05'~SSZ
slubs. The central section of the lower portion of slug 300 does not
contact core 510 so that there is no impedance to the withdrawal of yarn
from the central portion of the core. The long external, transverse cross-
sectional dimension of both the upper portion and the lower portion of slug
300 is less than the long transverse cross-sectional dimension of channel
278 so that slug 300 can rock back and forth slightly on members 306 and
308 to accommodate slight differences in the height of the end portions of
the core.
As the yarn is withdrawn from tower 270, the upper end of core
510, and therefore slug 300, move vertically upwardly and downwardly as
determined by the rate at which the yarn is withdrawn in relation to the
rate of upward movement of the core. Magnet 312 and switches 328, 330,
332, 334 and 336 cooperate to control the height of the core.
Switches 328, 330 and 336 are safety limit switches. If the
height of yarn core 510 increases to the point where magnet 312 moves into
proximity with switch 330, the switch closes, and the driving means are
deactivated for cam 190, feed rolls 68 and 70, and crimp control rolls
122 and 124 so that no more yarn is fed into the device. If the height
of the yarn core decreases so that magnet 300 moves into proximity with
20 switch 336 closing such switch, the driving means for both the yarn feed
devices and yarn winder 330 are deactivated. These are both abnormal
conditions and occur only under such circumstances as when the yarn
breaks between the crimper and winder, or between the source of yarn supply
and feed rolls 38 and 40. Switch 328 is an auxiliary safetycut-off switch
which keeps the crimpers from being operated if the magnet moves above
switch 330.
During normal operating conditions, magnet 312 moves vertically
upwardly and downwardly between switches 332 and 334; both of which are
operably connected to the winder driving means. When magnet 224 moves
105'~552
into proximity with switch 332, closing such switch, winder 512 is driven
at 100~ of a predetermined speed. This predetermined speed is slightly
greater than the speed required to withdraw the yarn from tower 270 at
the same rate at which it is fed into the tower. Therefore, the upper end
of core 152 and slug 300 will gradually move downwardly until magnet 312
moves into proximity with switch 334, closing switch 334. When switch 334
is closed, the winder is driven at a speed less than the aforementioned
predetermined speed, for example, at 80% of the predetermined speed. At
such lower speed the winder withdraws yarn at a rate which is less than that
at which it is fed into tower 270. In this manner, the upper end of the
core and the slug move upwardly and downwardly continuously a distance
approximately e~ual to the distance between switches 332 and 334, thus
maintaining the upper end of the core within a predetermined range.
While the foregoing constitutes a detailed description of a
preferred embodiment of the apparatus of the invention, it is recognized
that modifications thereof will occur to those skilled in the art.
- 26 -
