U.S. patent number 3,707,299 [Application Number 05/128,363] was granted by the patent office on 1972-12-26 for stuffer crimper with driven choke members for pressure control in the crimping zone.
This patent grant is currently assigned to Joseph Bancroft & Sons Company. Invention is credited to Alexander L. Trifunovic.
United States Patent |
3,707,299 |
Trifunovic |
December 26, 1972 |
STUFFER CRIMPER WITH DRIVEN CHOKE MEMBERS FOR PRESSURE CONTROL IN
THE CRIMPING ZONE
Abstract
A stuffer crimper fed with yarn from a pair of feed rolls having
a chamber defining a crimping zone adjacent the feed rolls followed
in succession by a heating zone and a cooling zone where the
pressure on the yarn core within said crimping zone and the
pressure on the core passing through the succeeding heating and
cooling zones are independently controlled by roller means having
core gripping surfacing projecting into said chamber at the
juncture of said crimping and heating zones, said roller means
being mounted and driven to rotate parallel to the axes of said
feed rolls at a speed related to the speed of said feed rolls.
Inventors: |
Trifunovic; Alexander L.
(Wilmington, DE) |
Assignee: |
Joseph Bancroft & Sons
Company (Wilmington, DE)
|
Family
ID: |
22434983 |
Appl.
No.: |
05/128,363 |
Filed: |
March 26, 1971 |
Current U.S.
Class: |
28/266;
28/270 |
Current CPC
Class: |
D02G
1/12 (20130101) |
Current International
Class: |
D02G
1/12 (20060101); D02g 001/12 () |
Field of
Search: |
;28/1,6,72,14 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Rimrodt; Louis K.
Claims
What is claimed is:
1. Yarn crimping apparatus comprising:
a stuffer crimper having a yarn core confining chamber defining
crimping, heating and cooling zones disposed successively along the
length of said chamber;
yarn feed rolls mounted at the inlet to said chamber to feed yarn
into said crimping zone to produce a core of crimped yarn within
said chamber;
roller means mounted to rotate parallel to the axes of said feed
rolls and disposed at the juncture of said crimping and heating
zones to independently control the pressure on the core within said
crimping zone relative to the pressure on the core in said heating
and cooling zones of said chamber, said roller means having core
gripping surfacing which projects into said chamber at said
juncture; and
means for positively rotatably driving said roller means
independently of the pressure exerted thereon by the core within
said crimping zone, said driving means being operable to drive said
roller means at a speed related to the yarn feed speed as
determined by the speed of said feed rolls.
2. Yarn crimping apparatus as recited in claim 1 wherein said
roller means comprises a pair of rollers with the core gripping
surfacing of said rollers projecting inwardly from opposite sides
of said chamber at said juncture.
3. Yarn crimping apparatus as recited in claim 1 wherein said core
gripping surfacing consists of gear-like teeth on said roller
means.
4. Yarn crimping apparatus as recited in claim 1 wherein said
roller means and said feed rolls are driven by a single source at
speeds proportional to one another.
5. Yarn crimping apparatus as recited in claim 1 wherein said
roller means comprises a pair of rollers disposed on opposite sides
of said chamber at said juncture of said crimping and heating zones
with the core gripping surfacing of each roller projecting inwardly
of said chamber, and said pair of rollers are driven at the same
speed.
6. Yarn crimping apparatus as recited in claim 5 wherein said pair
of rollers are connected by gearing externally of said chamber to
rotate simultaneously.
7. Yarn crimping apparatus as recited in claim 5 wherein each of
said pair of rollers has gear-like teeth on the exterior thereof to
provide said core gripping surfacing.
8. Yarn crimping apparatus as recited in claim 1 wherein core
retarding means is provided to engage the yarn core within said
chamber in said cooling zone to control the pressure on the core
within said heating and cooling zones of said chamber but beyond
the position of said roller means.
9. Yarn crimping apparatus as recited in claim 8 wherein the
cooling zone of said chamber is formed by a parallel bar cage
confining the yarn core therewithin, said core retarding means
comprises spaced tines extending inwardly of the bars of said cage
to engage the yarn core, and said tines are adjustably biased
against the core to control the pressure on the core in the heating
and cooling zones of said chamber.
10. Yarn crimping apparatus comprising:
a stuffer crimper having a yarn core confining chamber defining
crimping, heating and cooling zones disposed successively along the
length of said chamber;
yarn feed rolls mounted at the inlet to said chamber to feed yarn
into said crimping zone to produce a core of crimped yarn within
said chamber;
wall means forming the crimping zone of said chamber;
a cage having a set of spaced parallel inwardly projecting rail
means disposed around the periphery of said chamber with the inner
surfaces of said rail means forming a continuation of said wall
means of the crimping zone, said rail means extending throughout
the length of the heating and cooling zones of said chamber for
confining and guiding the yarn core therethrough;
roller means mounted to rotate parallel to the axes of said feed
rolls and disposed at the juncture of said crimping and heating
zones to independently control the pressure on the core within said
crimping zones relative to the pressure on the core in said heating
and cooling zones of said chamber, said roller means having core
gripping surfacing which projects into said chamber at said
juncture; and
means for positively rotatably driving said roller means
independently of the pressure exerted thereon by the core within
said crimping zone, said driving means being operable to drive said
roller means at a speed related to the yarn feed speed as
determined by the speed of said feed rolls.
11. Yarn crimping apparatus as recited in claim 10 wherein said
wall means forming the crimping zone of said chamber have the side
walls diverging from the bite of said feed rolls to the mounting
position of said roller means.
Description
GENERAL BACKGROUND OF THE INVENTION
This invention is generally concerned with yarn crimping apparatus
and, particularly, relates to stuffer crimpers of the type wherein
a yarn is fed between feed rolls into one end of a chamber to form
a core of crimped yarn which is advanced through the chamber by the
pressure and build up of crimped yarn introduced by the feed rolls.
More specifically, this invention is concerned with a stuffer
crimper fed with yarn from a pair of feed rolls where the chamber
through which the core of crimped yarn passes defines a crimping
zone adjacent the feed rolls followed in succession by a heating
zone and a cooling zone and is directed to obtaining independent
control of the pressure on the core passing through the crimping
zone relative to the pressure on the core passing through the
succeeding heating and cooling zones.
In the prior art of yarn crimping utilizing stuffer crimper
apparatus, effort has been directed to achieving uniformity in the
crimping action and also toward obtaining optimum control, as
desired for different yarn end uses, of the leg length for the yarn
crimps. Depending upon the use to which the crimped yarn product is
to be put, longer or shorter crimp leg lengths are desired. Also,
control of the sharpness of the bend or crimp to obtain the desired
bulk for the crimped yarn product has been an objective in prior
stuffer crimper developments. For example, in the heavier denier
yarns which find particular application as carpet yarns, the
achievement of a long leg length for the yarn crimps and a sharp
angle between the successive legs in the crimped yarn is desirable
for optimum bulk and results when the yarn is incorporated in the
finished carpet. The problem has been in being able to successfully
and reliably, with repeatability, obtain control of the crimp leg
length and crimp angle in yarn.
It is a principal object of the instant invention to provide a
stuffer crimper wherein effective independent control of the
pressures applied to the yarn core in the crimping zone relative to
that in the heating and cooling zones can be achieved.
It is a further important object of this invention to provide yarn
crimping apparatus wherein precise control of the pressure imparted
to the yarn core in the crimping zone of a stuffer crimper chamber,
immediately above the feed rolls, can be obtained and this pressure
rendered independent of the frictional or other back pressure to
which the core is exposed in passing through the subsequent heating
and cooling zones of the stuffer crimper chamber.
Another object of this invention is to provide positively driven
roller means at the outlet of the crimping zone, adjacent the feed
rolls which introduce yarn to the stuffer crimper chamber, to
control the pressure on the core within the crimping zone by such
roller means being driven in relation to the yarn feed speed and
being rotated parallel to the axes of the feed rolls.
A further object of the invention is to provide a stuffer crimper
having a yarn core confining chamber including crimping, heating
and cooling zones disposed successively along its length with
driven roller control means at the outlet of the crimping zone
operable to control the pressure to which the core is exposed in
such zone above the feed rolls and wherein the core above such
roller control means is exposed to low frictional drag in passing
through the heating and cooling zones of the stuffer crimper
chamber.
Also an object of the invention is to provide a stuffer crimper of
the above type which is particularly adapted for crimping heavy
denier yarns such as employed in carpet manufacture.
A more general object of this invention is in providing a yarn
crimping apparatus of the stuffer crimper type having novel and
improved characteristics.
In general, a preferred embodiment of the invention for crimping
yarn provides a yarn core confining chamber with crimping, heating
and cooling zones disposed successively along its length and yarn
feed rolls mounted at the inlet to such chamber to feed yarn into
the crimping zone and form a core of yarn within the chamber.
Roller means mounted to rotate parallel to the axes of the feed
rolls are disposed at the juncture of the crimping and heating
zones with such roller means having a core gripping surfacing
projecting into the chamber and being driven at a speed related to
the yarn feed speed so as to independently control the pressure on
the core within the crimping zone relative to the pressure to which
the core is subjected to in the heating and cooling zones of the
chamber.
The above-mentioned roller means may be driven at different speeds
relative to the yarn feed speed to thereby control and vary as
desired the back pressure to which the yarn core is subjected in
the crimping zone disposed immediately adjacent the feed rolls. By
selecting different driving speeds for the control roller means and
thereby obtaining different back pressures on the crimped yarn core
in the crimping zone, it has been determined that for a given yarn
feed speed, as determined by the speed of the feed rolls, the leg
length of the crimp in the yarn can be shortened or lengthened with
a degree of predictability such that a desired final crimped yarn
product can be obtained by simply setting the proper drive speed of
the control roller means which rotate parallel to the axes of the
feed rolls.
As a further feature of the driven control roller means, the core
gripping surfacing thereon may advantageously consist of gear-like
teeth on the circumference of the roller means. This surfacing is
beneficial in assuring positive and non-slipping interengagement
between the roller means and the crimped yarn core which thereby
achieves the desired positive control of the back pressure to which
the yarn is exposed when it enters the crimping zone under the
introducing force imparted to the yarn as it passes from the bite
of the feed rolls.
A further feature of the invention follows from utilization of the
above-described back pressure control in the crimping zone achieved
by the positively driven roller means combined with provision of a
relatively low friction chamber construction where the chamber of
the stuffer crimper extends through the heating and cooling zones.
Thereby, the frictional resistance to the crimped yarn core moving
through the heating and cooling zones, beyond the driven roller
control means, is reduced. With this reduced frictional back
pressure, control and variation of the pressure on the core moving
through the heating and cooling zones may also be independently
controlled and varied by utilizing a core retarding means such as a
weight biased rake choke where the tines of the rake choke extend
into a parallel bar cage, forming the chamber for confining the
yarn core within the cooling zone, and engage the core to set up
the desired back pressure so that the particular sharp crimp angle
for the yarn to be produced will be obtained and set as the core
passes through the heating and cooling zones.
Various other objects and details of construction will be apparent
as the nature of the invention is more fully disclosed. Such
invention will be better understood from the following description,
taken in connection with the accompanying drawing in which a
specific embodiment has been set forth for purposes of
illustration.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a diagrammatic perspective view, with certain parts shown
in exploded relation, of the stuffer crimper apparatus of the
instant invention; and
FIG. 2 is a sectional view taken along line 2--2 of FIG. 1 showing
the relationship of the pair of driven control rollers to the
chamber at the junction of the crimping and heating zones.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
On FIG. 1 of the drawing, the yarn crimping apparatus in the form
of a stuffer crimper 10 is shown in somewhat diagrammatic form in
relation to the related components employed in supplying yarn to
the stuffer crimper and winding up the crimped yarn withdrawn from
the stuffer crimper. Thus, description will be given as to the
general path for the yarn in moving through the equipment which, of
course, includes as the principal yarn treating component the
stuffer crimper 10.
A suitable yarn supply 12 is provided from which the yarn Y is
drawn through an appropriate tension gate 14 and then passes over
the guide 16 of a yarn traverse 18. The guide 16 shuttles back and
forth under control of rotating traverse 18 to distribute the yarn
back and forth across the length of the bite of the feed rolls 20
of the stuffer crimper 10.
As is conventional in stuffer crimpers, the feed rolls 20 are
geared together to operate at the same speed. As shown on FIG. 1,
the feed rolls 20 are driven by an appropriate motor 22. Also as
previously known, the traverse 18 is driven as by belt 24 from the
drive shaft of motor 22 so that the traversing movements of yarn
guide 16 and feed of the yarn back and forth along the length of
the bite of feed rolls 20 is accomplished in relation to the yarn
feeding speed of the feed rolls.
As the yarn Y passes between the bite of feed rolls 20, it enters
into the crimping area 26 of the chamber and is therein crimped
into a core of yarn within this area of the stuffer crimper
chamber.
In the illustrated embodiment, the crimping zone of the chamber is
formed by the walls of nose pieces 28 and 30. These pieces are
shown separated on FIG. 1 to better illustrate the interior of the
crimping zone. The two nose pieces, when assembled, provide a
saddle which closely conforms with the surfaces of the feed rolls
20 to receive the yarn as fed through the bite of the feed rolls to
form the crimped yarn core. The side walls of the nose pieces 28
and 30 extend from the bite of the feed rolls and saddle up to the
control roller means, hereinafter described, in the manner shown on
FIG. 2. The crimping zone extends upwardly, including area 26, from
the bite of feed rolls 20 through the portion where the core of
crimped yarn is confined within the walls of nose pieces 28 and 30
to the control roller means, this crimping zone being identified A
as shown on FIG. 1 of the drawing.
Adjacent the upper end of the nose pieces 28 and 30 are a pair of
rollers 32 and 34, appropriately journaled to rotate about axes
parallel to each other and also parallel to the axes of rotation of
the feed rolls 20. The parallelism of the axes of rollers 32 and 34
to the axes of the feed rolls 20 is of importance in relation to
the action of yarn traverse 18 relative to feed rolls 20. As
described above, the yarn traverse lays the yarn back and forth
across the length of the bite of the feed rolls 20. By having the
rollers 32 and 34 parallel to the feed rollers, these rollers apply
a uniform back pressure through the crimped yarn core across the
entire bite of the feed rolls.
These rollers 32 and 34 provide the control roller means and are
mounted such that the periphery thereof project into the chamber
from opposite sides at the upper end of the crimping zone A. Above
the rollers 32 and 34, the heating zone of the stuffer crimper
chamber starts and above the heating zone is the cooling zone in
the embodiment illustrated.
The rollers 32 and 34 have the shafts on which they are mounted
interconnected by gears 36 so that the two rollers will be rotated
simultaneously. As shown, the roller 32 has its shaft driven,
through belt 38, by the driving shaft of motor 22 which also drives
the feed rolls 20. Thus, rollers 32 and 34 are driven at a speed
related to the rotative speed of the feed rolls 20 and
consequently, related to the yarn feed speed as it enters the
crimping area 26 from the bite of rolls 20.
In the embodiment, as illustrated, each of the rollers 32 and 34
has a surface formed thereon such that they will effectively grip
the core of crimped yarn as it moves upwardly from the crimping
zone within nose pieces 28 and 30 to the position of rollers 32 and
34. In the preferred embodiment, these rollers 32 and 34 have the
core gripping surfacing provided by gear-like teeth formed on the
periphery of and extending longitudinally of each of these rollers.
The core gripping surfacing in the form of these gear-like teeth
and the relationship of the rollers 32 and 34 is best shown in the
sectional view of FIG. 2.
By reason of the axes of the rollers 32 and 34 being parallel to
the axes of the feed rolls 20, the core in the rectangular stuffer
crimper chamber, as illustrated, is effectively controlled as to
the pressure imparted thereto within the crimping zone A. Thus,
this pressure in the crimping zone is isolated or made independent
of that pressure which may be desired or may exist in the heating
and cooling zones of the chamber disposed above the location of
rollers 32 and 34. Likewise by changing the driven speed of rollers
32 and 34, the amount of back pressure applied on the core below
the rollers may be increased or decreased. By so increasing or
decreasing this back pressure, the leg length of the crimps
produced into the yarn, as it is introduced to the inlet of the
crimping chamber, can be effectively increased or decreased. In any
event, by the driven control roller means of this invention, the
pressure applied to the yarn core in the crimping zone is isolated
from whatever pressure exists, be it frictional resistance pressure
or introduced back pressure, in the heating and cooling zones and
this latter pressure will be isolated from the crimping zone
pressure.
In the preferred embodiment illustrated, the control rollers are
provided with gear teeth on their periphery and along their length.
These teeth, although projecting into the chamber of the stuffer
crimper 10 at the upper end of the crimping zone but still closely
adjacent the bite of the feed rolls, are spaced as shown in FIG. 2
such that the core in moving upwardly through the chamber is
gripped but not unduly distorted or disturbed. The objective of the
control rollers 32 and 34 is to use the driving speed of these
rollers to set the back pressure on the core in the crimping
chamber in relation to the rate of yarn fed by rolls 20 into the
crimping zone and also use this driving force on the rollers 32 and
34 to provide any force necessary to grip and move the core
onwardly through the succeeding heating and cooling zones of the
chamber.
Whereas the gear-like teeth provide the preferred core gripping
surfacing on the rollers, it is to be understood that other
different types of surfacing can be employed. By appropriately
spacing the rollers to alter the extent to which the core gripping
surfacing thereof projects into the chamber, different surfacing
than gear teeth, such as grooves, roughening, or other gripping
surface, may be employed. The important objective is that the
surfacing be proper for the particular yarn, pressure conditions of
the core and other parameters in operation of the stuffer crimper.
Thus, the core gripping surfacing on the rollers must properly grip
the core to give the controlled back pressure in the crimping zone
and still feed the core on through the heating and cooling zones
with the desired pressure in these latter two zones.
Although a pair of rollers each having core gripping surfacing on
the periphery thereof have been illustrated in the form of rollers
32 and 34, it is to be understood that under some conditions a
single roller with appropriate core gripping surfacing on its
perimeter may be employed. In this event, the core will be gripped
with the pressure in the crimping zone and pressure in the heating
and cooling zones independently controlled by this one roller
controlling core movement by pressing the core against the wall of
the crimping zone portion of the chamber opposite the location of
such single roller.
It also will be understood that as illustrated where the rollers 32
and 34 are intergeared to rotate together and are then driven from
the single power source of motor 22, which also drives feed rollers
20, the rollers 32 and 34 may be driven by a separate power source
than that used to drive the feed rolls 20. Obviously, the driving
speed of rollers 32 and 34 is desirably related to the rate of yarn
feed which is determined by the rotative speed of feed rolls 20 and
thus to get optimum results in control of pressure in the crimping
zone of the chamber the rollers 32 and 34 are advantageously driven
at a speed related to that of the feed rolls.
Particular attention is drawn to the ample spacing surrounding the
rollers 32 and 34, as shown in FIG. 2, where they are mounted to
project inwardly of the inner walls of the nose pieces 28 and 30.
The provision of ample space around the rollers, such as shown on
FIG. 2 of the drawing, is important in that it better facilitates
movement of the crimped yarn core upwardly out of the crimping area
26 and on into the heating zone. Where a close tolerance is
provided at the point where the walls of the chamber approach the
perimeter of the rollers 32 and 34, it has been found that the yarn
filaments tend to get snarled and broken by becoming pinched
between the teeth on the rollers and the adjacent stationary wall
portions.
Above the position where the core gripping surfacing of the rollers
32 and 34 projects into the chamber of the stuffer crimper 10, the
core of crimped yarn passes into the heating zone. Thus, the driven
control roller means is disposed at the juncture of the crimping
zone and the heating zone. Beyond the heating zone the core moves
into the cooling zone. In the embodiment as illustrated, the
passage of the core within the heating and cooling zones comprises
a length of the chamber designated by B on FIG. 1.
The heating zone portion of the stuffer crimper chamber is provided
by a cage chamber construction having rail means formed with
parallel inwardly projecting ribs 40 disposed around the periphery
of the chamber. In the heating zone, this cage and the ribs 40 are
formed on the interior of the half sections 42 and 44, shown in
exploded relation on FIG. 1 to better illustrate the interior of
the chamber in the heating zone. Of course, the half sections 42
and 44 will each be provided with appropriate heating means (not
shown) to elevate the temperature of these sections and thereby
produce the required temperature for treatment of the crimped yarn
core therewithin. The ribs 40 forming the cage construction of the
chamber in the heating zone serve to reduce the area of engagement
of the chamber with the yarn core in this zone and thereby reduce
or minimize the frictional drag on the core as it moves upwardly
through the heating zone.
Above the heating zone formed within the sections 42 and 44, the
cage chamber continues with rail means being provided by parallel
bars 46 disposed around the periphery of the chamber in the portion
of the chamber which forms the cooling zone. Thus, the inwardly
projecting surfaces of the bar cage formed by bars 46 provide rail
means as continuations of the individual ribs 40 in the sections 42
and 44 of the heating zone chamber portion and the core of crimped
yarn is confined and guided onwardly from the heating zone into the
cooling zone. The parallel bars 46 like the ribs 40 in the heating
zone provide rail means offering minimal frictional resistance to
passage of the core through the cooling zone.
The pressure imparted to the core is to an extent dependent upon
the frictional resistance which the core encounters in moving along
the rail means within the heating and cooling zones. Of course, the
pressure within the crimping zone A is isolated from the pressure
to which the core is exposed to in the heating and cooling zones by
the driven control roller means provided by toothed rollers 32 and
34 in the illustrated embodiment. However, it is desirable to apply
a controlled back pressure to the core in the heating and cooling
zone so that the desired setting of a sharp crimp angle in the yarn
filaments can be achieved. Accordingly, a core retarding means, in
the form of a rake element 48 having tines 50, is pivotally mounted
so that the tines 50 can be urged inwardly between the parallel
bars 46 of the cooling zone portion of the chamber with the tines
engaging the yarn core and thereby establishing resistance to
movement of the core through the cooling zone and consequently
establishing the back pressure existing on the core within the
heating and cooling zones above the driven control rollers 32 and
34. The rake element 48 may have a suitable arm 52 extending
therefrom with a weight 54 suspended from the outer end thereof. Of
course, variation in the amount of the weight 54 will determine the
extent to which the tines 50 of the rake element 48 are biased
inwardly against the movement of the yarn core within the cooling
chamber and consequently, determine the back pressure to which the
yarn core is subjected to in passing through the heating and
cooling zones.
A further advantage flows from providing the driven control rollers
32 and 34 in relation to moving the crimped yarn core through the
length of the chamber designated B on FIG. 1 encompassing the
heating and cooling zones. These rollers independently advance the
core of crimped yarn through the zone B. In so doing, deposits that
may build up on the walls of the chamber and the length of the
chamber zone B do not significantly effect the back pressure on the
yarn core in crimping zone A. Consequently, there is more
flexibility in determining the length of the chamber that can be
used and the chamber itself does not have to be cleaned as often
when driven control rollers such as 32 and 34 are used.
As illustrated, a pair of core retarding means involving rake
elements 48, one being mounted on each side of the bar cage forming
the cooling zone portion of the chamber are illustrated in FIG. 1.
The second core retarding rake element and associated parts are
shown in exploded fashion to better illustrate the relationship of
the first rake element to the bar cage of the cooling zone.
Beyond the core retarding means formed by the rake elements 48 on
opposed sides of the cooling zone bar cage, the core continues
through the bar cage to a sensing frame 56 which is pivotally
mounted at 58 and rests on the end of the core of crimped yarn. The
frame is connected to control a rheostat 60 which is to control the
yarn winder speed, depending upon the varying height of the upper
end of the crimped yarn core in the bar cage cooling zone of the
stuffer crimper chamber. The winder withdraws the crimped yarn from
the end of the core and between the parallel bars of the sensing
frame 56.
In being withdrawn from the core of crimped yarn, the yarn passes
out of the bar cage of the cooling zone through guide eyelets 62
and 64, and then over a traverse guide 66 which lays the yarn in
windings on the package 68. The package is mounted to be rotatably
driven by drive motor 70. As shown, the speed of drive motor 70 is
controlled by the setting of rheostat 60 so that the position of
the end of the crimped yarn core within the cooling zone will be
maintained relatively constant, with the package 68 operating
faster or slower to withdraw the crimped yarn as needed to maintain
such constant position of the end of the crimped yarn core.
It is to be understood that the form and embodiment of the
invention herein shown and described is to be taken only as a
preferred representation of the invention and that various changes
and modifications in the arrangement of the components, parts,
units, etc. may be resorted to without departing from the spirit or
scope of the appended claims.
* * * * *