Note: Descriptions are shown in the official language in which they were submitted.
CA 02288214 1999-10-25
THE DYEING MACHINE FOR APPLYING TREATMENT
AGENT TO FABRIC
FIELD OF THE INVENTION
The present invention relates generally to a spray dyeing apparatus and in
particular to a spray dyeing apparatus having a construction to allow the
fabric
breadth to be substantially fully expanded during dyeing process with a
pressure
difference created between the upper side and the lower side of the expanded
fabric,
together with vibration of the fabric caused by high speed air streams under
the fabric,
to enhance the dyeing effectiveness and efficiency.
SUMMARY AND BACKGROUND OF THE INVENTION
The term spray dyeing apparatus used herein is intended to indicate a dyeing
apparatus in which the liquid dye and other fabric treating agent are brought
into
contact with the fabric in an atomized form by means of spray nozzles arranged
above
the fabric. The dyeing apparatus in accordance with the present invention
provides a
flat fabric support surface of a sufficient width which allows the fabric to
be
substantially fully expanded in the breadthwise direction when the fabric is
moved
through the dyeing apparatus so as to receive the atomized dye thereon across
the
breath thereof to carry out dyeing operation. The present invention also
discloses a
construction of the dyeing apparatus which comprises a plurality of directing
nozzles
located under the expanded fabric to generate high speed air streams to move
and
support the fabric on the support surface. The high speed air streams also
create a
low pressure zone under the expanded fabric which causes a pressure difference
between the upper and lower sides of the expanded fabric. The pressure
difference
causes the fabric to violently vibrate so as to enhance the penetration and
diffusion of
the dye into the fabric. Thus a dyeing operation of high efficiency, low
energy
consumption, low bath ratio and low pollution may be achieved.
The present invention is particularly related to a dyeing apparatus in which
an
effect that is caused by the high speed air streams under the expanded fabric
creating
a low pressure under the fabric and the massive transfer of energy between the
high
speed air streams and the fabric causeing the fabric to continuously move
downstream
leads in a high efficient penetration and diffusion of the dye within the
fabric and also
a very effective way to remove un-wanted particles or impurities from the
fabric and
to clean, rinse and bleach the dyed fabric in a very efficient way so as to
complete the
CA 02288214 1999-10-25
2
overall dyeing operation in a very short time as compared with the
convertional
dyeing apparatus.
In the conventional air flow type or liquid flow type dyeing apparatus, the
fabric is moved by means of a fabric driving wheel and a driving nozzle set.
The
fabric is constrained to be in the form of a tight bundle, similar to a rope,
to pass
through the throat of the driving nozzle. The fabric is also constrained in a
circular
fabric guide tube having a limited, small diameter in order to prevent the
kinematic
energy of the moving fabric from losing due to expansion of the fabric and
thus
maintain the speed of the fabric in a desired level. Thus, the fabric is
constrained to
the form of rope in moving through the fabric is constrained to the form of
rope in
moving through the fabric guide tube inside which the dyeing operation is
actually
carried out. The conventional air flow type or liquid flow type dyeing
apparatus is
generally designed to make use of the driving force generated by air stream
nozzles or
liquid stream nozzles (the driving nozzle) or the combination thereof to force
the
fabric to move into and through the fabric guide tube. The technique of the
liquid
flow type dyeing apparatus has been disclosed in certain prior art patents so
that no
further discussion is given here. As to the air flow type dyeing apparatus, it
is
defined as comprising an air driving nozzle mounted on the liquid driving
nozzle or
mounted at the upstream and downstream side to provide auxiliary driving force
and
to soften the hard driving action generated by the liquid driving nozzle and
also to
provide a dyeing operation of low bath ratio. In general, the air flow type
dyeing
apparatus is classified as high temperature, high pressure type and regular
temperature,
regular pressure type, which comprises, in the construction, a fabric storage
tank, a
fabric guide tube, a fabric driving wheel, a dye driving nozzle set, an air
driving
nozzle set, a fabric folding device, a dye pump, a blower, a heat
exchanger/filter
device for temperature control and a control unit. In construction, the fabric
guide
tube is arranged above the fabric storage tank and extending in the same axial
direction. The upstream end and the downstream end of the fabric guide tube
are
respectively connected to and in communication with a lateral side end of the
fabric
storage tank to allow the fabric to be driven and guided by the driving wheel
from the
fabric storage tank to a driving nozzle set. By means of the dye and air
streams
generated by the driving nozzle set, the fabric is driven into and through the
fabric
guide tube and eventually moving from the downstream side back into the fabric
storage tank. The dye and air exiting the fabric guide tube are re-circulated
through
respective return tubes to the dye pump and the air blower. The fabric that
moves
into the fabric storage tank through a laterally rear side of the tank is then
moved
toward the laterally front side and driven out of the fabric storage tank by
the fabric
driving wheel to continuously circulate through the fabric storage tank and
the fabric
CA 02288214 1999-10-25
3
guide tube.
FIGS. 1 and 2 respectively show the conventional air flow type and liquid flow
type dyeing apparatus, both comprising a fabric storage tank A and a fabric
guide tube
A1. The fabric guide tube A1 has a dye driving nozzle All(for liquid flow
type) or
an air driving nozzle A12(for air flow type) at an upstream inlet. For
simplicity, the
dye driving nozzle All and the air driving nozzle A12 are generically referred
to as
driving nozzle and designated with reference A2 in the following description.
The
fabric guide tube A1 has a downstream outlet connected to and in fluid
communication with the fabric storage tank A to define a continuous fabric
circulation
loop through which a fabric to be dyed, designated with reference B, is moved.
During the dyeing operation, the fabric B inside the fabric storage tank A is
driven
therefrom to the driving nozzle A2 by means of a fabric driving wheel A3 and
is dyed
by means of the dye and/or air stream generated by the driving nozzle A2. The
dye/air stream also forces the fabric B to move through the fabric guide tube
A1 and
back into the fabric storage tank A. The dye C inside the fabric storage tank
A is
conducted by means of a return tube A4 located under the fabric storage tank A
to the
dye pump A5. The air that flows into the fabric storage tank A with the fabric
B is
conducted by an air return tube A6 disposed above the fabric storage tank A to
the air
blower D. The fabric B that moves out of the fabric guide tube Al and enters
the
laterally rear side of the fabric storage tank A is driven frontward by means
of for
example inclination of the fabric storage tank A or gravity or potential
difference
thereof to repeat the dyeing cycle.
Thus, in the conventional air flow type dyeing apparatus, the movement of the
fabric is achieved by the fabric driving wheel A3 and the dye/air stream
generated by
the driving nozzle A2 that is located at the laterally front end upstream
inlet so as to
allow the fabric B to move into and through the fabric guide tube A1 and thus
providing a dyeing operation of low bath ratio. In the conventional apparatus,
the
driving nozzle A2 is constructed to have a nozzle opening or mouth of circular
cross
section, as shown in FIGS. 3 and 4. In order to control the flow rate of the
stream
from the driving nozzle A2, a variety of adjustable construction of the
driving nozzle
have been developed which gradually takes place of the driving nozzles of
fixed
nozzle opening size or exchangeable nozzles. In face, the operation of the
adjustable
driving nozzle A2 in the dyeing process is substantially identical to the
fixed type
nozzle, for the fabric B is still constrained to be in the form of a rope in
passing
through the nozzle A2. Since the adjustable driving nozzle constitute no
improvement to be discussed in the present invention, no further detail will
be given.
A1 through in the air flow type and liquid flow type dyeing apparatus shown in
FIGS.
1 and 2, identical members or parts are designated with the same references,
yet
CA 02288214 1999-10-25
4
description that is given as follows is based on the air flow type dyeing
apparatus.
The fabric B passes through the central throat A22 of the rising opening A21
of the
driving nozzle A2 with the due/air stream from the nozzle A2 surrounds the
fabric at
the downstream side and forms a constraint force on the fabric B. The dye/air
stream leaving the nozzle A2 spreads and transfers the kinematic energy
thereof to the
fabric to generate a driving force in the downstream direction. To prevent the
energy
from being over-spread and thus causing significant reduction of the fabric
speed and
to achieve the desired dyeing effect, in the conventional air flow type or
liquid flow
type dyeing apparatus, both the driving nozzle A2 and the fabric guide tube A1
through which the fabric B is to move have a circular cross section to provide
transfer
and saving of energy. However, using such a constraint configuration of
driving
nozzle A2 for driving the fabric B downstream frequently causes damages on the
fabric B due to the fact that when the fabric B moves through the throat of
the driving
nozzle A2 and the fabric guide tube Al, the fabric is subject to the
constraint of the
throat of the driving nozzle A2 and the fabric guide tube AI to force the
fabric B to
form a rope like configuration which requires the fabric to have a large speed
in
passing through the nozzle, thus causing violent impact of the fabric B onto
the side
walls of the throat of the driving nozzle A2. Also, when the jet force from
the
driving nozzle A2 is excessive, the fabric B is alos subject to great impact
from the
dye/air stream, which may cause damage on the fibrous structure of the fabric
B so as
to lead in separation and detachment of fibers. On the other hand, lowering
down
the jet force of the driving nozzle A2 may not provide a sufficient
penetration force of
the dye into the rope-like configuration of the fabric B. The moving speed of
the
fabric B is also reduced and thus lengthens the circulation period of the
fabric B.
Further, when the fabric B passes through the driving nozzle A2, the fabric B
is
usually folded breadthwise and tightly squeezed together. Folding traces are
thus
formed on the fabric B. Although compacting the fabric B to form a rope-like
configuration is helpful in transferring energy from the dye/air stream to the
fabric B
and moving the fabric B downstream, yet with such a compact configuration of
fabric,
it is difficult to have the dye uniformly and sufficiently penetrate into the
fabric B.
In other words, it requires great energy to drive the dye deep into the fabric
B and also
to expel the dye that has already penetrated into the fabric B to get out of
the fabric B
so as to allow new dye to move in. Thus to overcome such a problem,
conventionally, the dyeing cycle is lengthened and dye streams are
continuously
provided by the driving nozzle A2 to impact onto the fabric B. This makes the
dyeing operation time- and labor-consuming.
The momentum that the driving nozzle A2 applies to the fabric B may be
calculated on the basis of the speed when the fabric B is passing through the
throat
CA 02288214 1999-10-25
A22 of the driving nozzle B. When the fabric B leaves the throat A22, the
velocity
reduces for the cross-sectional area of the ring-like mouth A21 of the driving
nozzle
A2 is smaller than that of the fabric guide tube Al which causes the dye flow
or air
flow to spread out and the spread of the air flow or dye flow makes the fabric
B slow
down. Since the fabric B itself is not a fluid, it has to fold or overlap to
accommodate the reduction of speed. This is particularly significant for all
cotton
fabric or fabric having a great unit weight . Thus the fabric B may get over-
crowded
and squeezed inside the fabric guide tube A1, causing an action like a piston
inside a
cylinder bore. Serious folding line problem may thus arise. Also, the friction
between the fabric guide tube Al and the fabric B is increased. As a matter of
fact,
in the conventional air flow type and liquid flow type dyeing apparatus, once
the
fabric B leaves the driving nozzle A2, due to the increase of space, most of
the
mementum is lost with the spread of the air flow or dye flow so that the
penetration of
the dye into the fabric B is reduced. Although theoretically, the expansion of
the air
stream or air flow may open the fabric B when the fabric B is leaving the
fabric guide
tube Al, yet since the fabric B is constrained to the form of a rope for quite
a long
during the dyeing operation, it is sometimes not possible to have the fabric B
opened
properly. Thus, conventionally, the air flow type dyeing apparatus is not
suitable for
all cotton fabric or fabric having great unit weight. Further, in the
conventional air
flow type dyeing apparatus, the fabric is only subject to the action of the
driving
nozzle A2, un-dyed spots may be found in the fabric B and thus the
effectiveness of
dyeing is poor.
Conventionally, the air flow type dyeing apparatus handles fabric in a batch
manner and the quantity of fabric that a batch may take is dependent upon the
size of
the fabric storage tank. The most common capacity of the fabric storage tank
is
between 100-200 Kg. If a batch is greater than the capacity, then the dyeing
operation must be carried out with more than one dyeing device. Alternately,
the
dyeing apparatus may be designed with a very large fabric storage tank which
is
divide into several channels each serving as an independent fabric storage
tank.
Besides the capacity of the fabric storage tank, the productivity capacity of
a dyeing
apparatus is also determined by the period of the dyeing cycle. Generally, a
dyeing
cycle takes approximately 2minutes which should not be shortened significantly
in
order to obtain an effective dyeing.
The movement of the fabric B inside the fabric storage tank A is usually
driven
by the inclination provided inside the tank A and the potential caused by the
stack of
fabric B inside the tank. This is particularly true for air flow type dyeing
apparatus.
Thus, the air flow type dyeing apparatus usually adapts a configuration of for
example "J","O" or "U" shape to provide such an altitude difference for
causing
CA 02288214 1999-10-25
6
movement of the fabric B inside the fabric storage tank A. Further, to protect
the
fabric B from over-friction with the fabric storage tank A, usually a layer of
low
friction coefficient material (not shown) is provided inside the fabric
storage tank A.
Thus, besides the difference in the factors discussed above, such as gravity
and
potential energy, bath ratio, momentum of dyeing fluid and the acceptable
folding line
for a given fabric, most of the dyeing apparatus, although having different
configuration, are operated in accordance with the same principle to achieve
dyeing
effect.
FIG. 5 shows a prior art liquid flow type dyeing apparatus created by the
present inventor, which is disclosed in Taiwan utility model No. 89941,
Chinese
utility model No. ZL 93209236.5, Chinese patent No. 93105099.5 and U.S. Pat.
No.
5,381,678. The present invention is an improvement over the liquid flow type
dyeing apparatus.
As shown in FIG. 5, the previous liquid flow type dyeing apparatus of the
present inventor has a configuration similar to the conventional liquid flow
type
dyeing apparatus shown in FIG. 1 which comprises a fabric storage tank A and a
fabric guide tube A1 disposed above the fabric storage tank A with laterally
front and
rear ends of the fabric guide tube A1 connected to the fabric storage tank A
to define
a continuous path for fabric B. The front inlet of the fabric guide tube A1
has a
driving nozzle A2 and the laterally front end of the fabric storage tank A has
fabric
driving wheel A3 to convey the fabric B from the fabric storage tank A to the
driving
nozzle A2 and then into the fabric guide tube A1 and finally back to the
fabric storage
tank A. The driving nozzle A2 generates dye stream to carry out dyeing
operation
on the fabric B and drives the dye C and the fabric B to pass through the
fabric guide
tube A1 and into the fabric storage tank A. The dye C collected inside the
fabric
storage tank A is then guided via a return tube A4 to a dye pump AS which
pressurizes and conveys the dye, via a dye circulation tube A8, to the driving
nozzle
A2 to be injected thereby onto the fabric B to drive the fabric B through the
fabric
guide tube Al. The fabric guide tube A1 comprises a plurality of directing
nozzles
A61 arranged on the bottom of the fabric guide tube A1 so as to allow the dye
C
which is pressurized by the pump AS and conveyed through a tube A7 to be
injected
in a downstream direction by the directing nozzles A61 for enhancing the
movement
and dyeing effectiveness of the fabric B.
In view of the drawbacks of the above described prior art dyeing apparatus,
the
present invention provides an improved air flow type spray dyeing apparatus.
Thus, an object of the present invention is to provide an air flow type spray
dyeing apparatus wherein no driving nozzle is provided at the front upstream
inlet of
the fabric guide tube and a substantially flat support having a sufficient
width is
CA 02288214 2003-07-17
provided on the bottom of the fabric guide tube to allow the breadth of the
fabric to be
substantially fully expanded in moving tln-<>tzgh the fabric guide tube so
that the fabric
is no longer constrained by a small cross section of the driving nozzle anc:l
the small
diameter of the prior art fabric guide tube and thus the abrasion of the
fabric and the
folding line problem of the fabric rnay be effectively c:lirninated,
Another object of the present invc:ntiotx is to prcavid~; a spray dyeing
apparatus
wherein the fabric; guide tube comprises a plurality of S~7aCed d1I'eCtL()n
nUZZIeS
disposed on the bottorr~ of the fabric g~.~id~ gibe tc:> gc,nerate high speed
air streams
under the fabric to float:, support and mceve the fabric n.nd a plurality of
spray nozzles
on the upper side of the fabric guide tube tt~ apply atantized dye liquid
ontcP the fabric
so as to effect a dyeing operation witlx a small quantity of dye. thus a
dyeing
apparatus of low bath ratio, low energy ccan surnpiion arid low pollution is
provided.
A further object of the present invention is to provide° a spray dyeing
apparatus
which generates a plurality of high sped ai~° streaixas to act upan the
underside of the
substantially fully expanded fabric so as to induce a violent vibration on the
fabric
which is partially caused by the impact of the air streams onto the fabric and
partially
by the pressure difference between the upper side and lower side of the fabric
induced
by the high speed of the air stream, which v ibration enln~nces the
penetration and
diffusion of dye into the fabric and thus significantly increases the degree
of
exhaustion of dye.
A further abject of the. present invc;ntion is to provide a spray dyeing
apparatus
wherein high speed air streams are generated ~r~~der the sul~stanCially fully
expanded
fabric and a low pressure zone is created ~~nd~°r tl~~ fatpric mhic:lr
allows the fabric to
be driven toward the high speed air strea~us to force tl~e air to tow out of
the fabric
from two breadthwise sides thereof for maintaining thc; full expansioru of the
fabric.
A further abject of the present inv~nticuu is to prcwide a spray dyeing
apparatus
wherein high speed air streams are generated cruder the fabric to cause
violent
vibration of the fabric which not only achieves a dyeing opec~atian with small
quantity
dye of high concentration, but also oite~ s th a removU of impurity or
contaminant
from the fabric.
A further object of the present invention is to provide a spray dyeing
apparatus
which allows liquid, such as dye or fresh water, to be injected to both the
upper and
lower sides o.f the fabric so as to effect a rinsing operaticm gar to effect a
dyeing
operation for heavy fabric.
CA 02288214 2003-07-17
8
To achieve the above objects, there is provided a fabric treating
apparatus comprising:
a fabric storage tank for receiving a fabric and a fabric guide passage
disposed on a top of the fabric storage tank, the fabric storage tank and the
fabric guide passage being connected to and ire fluid communication with each
other at a front side of the fabric guide passage and an opposite rear side of
the
fabric guide passage to define a continuous path far the fabric to
continuously
circulate therein from the fabric storage tank into the front side of the
fabric
guide passage to move through the fabric guide passage to the rear side of the
to fabric guide passage and then back into the fabric storage tank, the fabric
guide
passage having a flat width formed between a front end inlet of the fabric
guide
passage and a wall, sufficiently to allow the fabric to fully expand breadth-
wise in
moving through the fabric guide passage, a cross section of a bottom wall of
the
fabric guide passage comprising a plurality of air direction nozzles disposed
at
intervals in a moving direction of the fabric so that the air direction
nozzles
disposed upstream are spaced from the air direction nozzles disposed
downstream, at a given distance, each one of the air direction nozzles having
a
reflex operation base plate disposed downstream, the reflex operation base
piates of the air direction nozzles being interconnected via the fabric guide
2 o passage and a blower, for guiding a pressurized air flow into the air
direction
nozzles for jetting, the pressurized air flow being able to move downstream
along surfaces of the reflex aperation base plates and under the fabric based
on
an interaction with the reflex aperation base plates" a pressurEa difference
between an upper side air flaw and a lower side air flow of the fabric in the
fabric
guide passage creating a low pressure zone under the fabric, a lower side of
the
fabric having a faster air flow than that of the opposite upper side of the
fabric,
causing a violent vibration on the fabric moving along the fabric guide
passage,
an effect of the pressure difference between the upper side air flow and the
lower side air flow of the fabric in the fabric guide passage, along with
gravity,
3 o moving the fabric toward and away from the bottoms wall of the fabric
guide
passage in a repeated manner, the fabric being exposed to the pressurized air
CA 02288214 2003-07-17
t> c.~
flow continuously to result in an efficient energy transfer there between to
increase a moving speed of the fabric; and
dye spray nozzles disposed on an upper side of the fabric guide passage
spraying a dye or a fluid onto the fabric substantially across a breadth of
the
fabric in an atomized form so as to enhance diffusion and penetration of the
dye
or the fluid into the fabric to allow the fabric to be treated by the dye or
the fluid
in an efficient manner, a multi-apertured net board being disposed on a wall
of
the fabric storage tank to conduct the pressurized air flow through an outlet
thereof to a dye return tube so as to prevent the pressurized air flaw being
to blocked or guided in an opposite direction when the pressurized air flow is
moving backwards, the dye or the fluid being separated from the pressurized
air
flow and guided through an outside of the multi-apertured net board onto a
lowermost part of the multi-apertured net board and into the dye return tube.
BRIEF T1ES~ItIPTh(JN OF THE dRAWINGS
The present invention will be better ur~derstaad from the following
description
of preferred embodiments thereof, with reference tca the attached drawings,
wherein:
FIG. 1 is a schematic side elevational, crc:ass-srrctional view showing a
2 0 conventional air flow type dyeing apparatus;
FIG. 2 is a schematic side elevaticanal, ~:r~:~ss-s~.~;tional view showing a
conventional liquid flow type dyeing apparatus;
FIG. 3 is a cross-sectional viev~~ showing a driving nozzle adapted in the
conventional air flow type dyeing apparatus;
FIG. 3A is an end view of the driving nozzle;
FIG. 4 is a cross-sectional view showing a driving nozzle adapted in the
conventional liquid flow type dyeing apparatus;
FIG. 4A is an end view of the driving nozzle;
FIG. 5 is a schematic° side elevatic-~n.al, c:;ross-s~..G~,ti.or~al
view showing another
conventional liquid flow type dweitug alapartrtns which is discloved in
C'.hinese utility
mode No. Zh 93209:236.x, C;hin~t.s~ patent Nca.c,?31()50~~>.:~ and U.S. Pat.
No.
30 Sy381,678;
CA 02288214 2003-07-17
FIG. 6 is a crass-sectional view sl~c~wir~g an adj useable directing nozzle
adapted
in the dyeing apparatus shown in FI(:;. 5
FIG. 7 is a fragmentary view of the directing nozzle shown in FIG. 6;
FIG. 8 is schematic side elevation, cross-secticanal view showing a spray
dyeing
apparatus constructed in accordance with the present invention;
FIG.9 is also a cross-sectional vie~~~ c~i" flue spray dyeing apparatus of the
present
invention;
FIG. 10 is a sectional view c~f the spray dyeing apparatus of the present
invention;
FIG. 11 is a side view of adjustable directing nozzle adapted in the spray
dyeing
1 o apparatus shown in FIG. 8;
FIG. 12 is a top view of the adjustable directing t~ozzl~,; and
FIG. 13 is a schematic side elevational., cross-sectional view showing a spray
dyeing apparatus constructed in accordance with another embodiment of the
present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to the drawings and in particular to Figs. 8 and 9 which
show a cross-sectional view of a spray dyeing apparatus in accordance with the
present invention, the spray dyeing apparatus of the present invention
2 o comprises a fabric storage tank 1, a fabric guide tube 11, a distribution
tube 12,
directing nozzles 121, a support plate 1 ~, spray nozzles 14, a dye pump 15, a
blower 16, fabric folding plate 17, fabric driving wheel 18, an inner holed
plate
or net 19, a dye heat exchanger 9 54, a filter 15~ and a dye feeding inlet
1151, a
dye return tube 151, a dye conveyor tube 152, are air return tube 161, an air
conveyor tube 162, a secondary dye c;c>nveyor or by-pass tube 16!~ and a dye
flow control valve 166.
With reference to FIGS. 8-10, the tabric storage tank 1 has a configuration of
circular tube for high pressure and high temperature dyeing operation, while
for
regular pressure and regular temperature, the c;c~nfiguration is generally a
:square tube
3 o Which is to enhance the movement o1 tlae fabric inside a low bath ratio
dyeing
apparatus, preferably C>-, L~- or inverted L~-shaped construcaion so as to
minimize the
space occupied thereby. As shown in l;'IC"r. 8, the dyeing apI>aratus
illustrated takes
CA 02288214 2003-07-17
C) ~
the configuration of an C>-shaped cross seetian with the fabric storage tank 1
defined
in the lower portion of the ~-shaped c:onliguration. °llue fabric guide
tube 11 is
mounted above the fabric storage tank I , ~:~~-ext~adirzg therewith in the
same axial
direction which is normal to the drGrwi~~g plan of FICi. ~. 'C'he fabric guide
tube 11
has an upstream inlet connected to and c~~>rxlrnvu~icatix~~; with a laterally
front end of
CA 02288214 1999-10-25
the fabric storage tank 1 and a downstream outlet 112 connected to and
communicating with a laterally rear end of the fabric storage tank 1 so as to
define a
circular closed loop for the circulation of fabric to be dyed which is
designated with
reference numeral 2 in the drawing. The lowermost portion of the fabric
storage
tank 1 is provided with a dye return tube 151. An air return tube 161 is
provided
above the dye return tube 151. An access hole 3 and a fabric driving wheel 18
are
provided at the laterally front end of the fabric storage tank 1,
substantially at the
interface between the fabric storage tank 1 and the fabric guide tube 11. The
fabric 2,
which has a given breadth, is driven partly by means of the fabric driving
wheel 18 to
move from the fabric storage tank 1 into the fabric guide tube 11 to be dyed
therein.
The fabric guide tube 11 comprises a flat base or bottom 13 having a
substantially
width (dimension in the axial direction), as shown in FIG. 10, to allow the
fabric 2 to
be fully expanded breadthwise when the fabric 2 is driven to move through the
fabric
guide tube 11. The fabric guide tube 11 comprises a plurality of spray nozzles
14
located on an upper side thereof and facing the fabric 2 so as to spray dye
onto the
fabric 2. A distribution tube 12 is provided under the base plate 13 of the
fabric
guide tube 12, having a width substantially corresponding to length of the
fabric guide
tube 11 which is defined as the dimension from the laterally front end of the
fabric
storage tank 1 to the laterally rear end of the fabric storage tank 1 to allow
air to be
substantially distributed along the length of the fabric guide tube 11 and a
length
extending in the axial direction of the dyeing apparatus. Preferably, the base
plate 13
constitutes a partition wall between the fabric guide tube 11 and the
distribution tube
12. A plurality of directing nozzles 121 are formed on the base plate 13 to
substantially extend in the length of the distribution tube 12 and spaced at a
pre-
determined distance in the width direction of the distribution tube 12. The
directing
nozzles 121 is configured to face downstream so as to provide air streams
under the
fabric 2 in the downstream direction, the air being supplied through the
distribution
tube 12. At a connection section 113 between the downstream outlet 112 of the
fabric guide tube 11 and the laterally rear end of the fabric storage tank 1,
a fabric
folding plate 17 is provided on wall 114 of the connection section 113 by
means of
pivot. The fabric folding plate 17 is controlled by any known means to
wingingly
reciprocate about the pivot so as to repeatedly and cyclically get into
contact with the
fabric 2 during the movement of the fabric 2 and thus force the fabric 2 to be
folded in
a neat and snug manner in moving from the fabric guide tube 11 back into the
fabric
storage tank 1. The fabric storage tank 1 is provided with a liquid/air
separation net
or holed plate 19 which is provided on the bottom of the fabric storage tank 1
with a
space defined therebetween so that when the fabric 2 which has dye carried
thereon
falls back into the fabric storage tank l,the fabric 2 is supported on the
liquid/air
CA 02288214 1999-10-25
11
separation net 19 to allow the dye to drop through the net 19 by means of
gravity and
collected in the space between the net 19 and the bottom of the fabric storage
tank 1.
The dye so collected is then drawn away, via the dye return tube 151,by a dye
pump
15. The dye is then pumped through a filter 153 and a heat exchanger 154 to
remove
un-wanted particles or impurity from the dye and to maintain the dye at a
given
temperature for dyeing operation. The dye so treated is then conveyed to the
spray
nozzles 14 through a dye conveyor tube 152.
Although in the embodiment illustrated in FIGS. 8 and 9. The support plate 13
defines a support surface of substantially flat structure with a width
sufficient to allow
the fabric to expand so as to enhance the dyeing effectiveness yet, as a
matter of fact,
the support plate 13 may not need to be a flat configuration and it only needs
the
support plate 13 to be of a sufficient width to allow the fabric to fully
expand in order
to achieve the dyeing operation provided by the present invention. For
example, an
another embodiment of the present invention is shown in FIG. 13 wherein the
support
plate 13 takes the form of an arc substantially concentric with respect to the
circular
configuration of the dyeing apparatus or the fabric storage tank l, the width
of the
base plate 13 in this embodiment being also sufficient for the breadth of the
fabric to
be substantially fully expanded Similarly, other configuration of the base
plate with a
smooth and gradual change in the overall contour also provides the same
effectiveness
as that shown in both embodiments of FIGS. 8 and 13.
As described above, in the dyeing cycle of the spray dyeing apparatus in
accordance with the present invention, the fabric 2 is pulled upward from the
fabric
storage tank 1 by the fabric driving wheel 18 and then conveyed into the
fabric guide
tube 11. The dye is conducted to the pump 15 via the dye return tube 151 and
then
pressurized and conveyed by the pump 1 S to the dye conveyor tube 152 via the
filter
153 and the heat exchanger 154 and finally reaches the spray nozzles 14
located on
the upper side of the fabric guide tube 1 to be sprayed onto the fabric 2 that
is moving
through the fabric guide tube 11. The dye is absorbed and carried by the
fabric 2
toward the outlet 112 of the fabric guide tube l and then returns to the
fabric storage
tank 1. The dye that returns to the fabric storage tank 1 passes through the
liquid/air
separation net 19 and is then collected at the lowermost portion of the fabric
storage
tank 1 from which the dye is again conducted to the pump 15 via the dye return
tube
151 so as to constitute a continuous dye circulation loop. The dye return tube
151 is
provided with a dye feeding inlet 1511 through which dye may be supplemented
or
other fabric treating agent or chemicals may be added into the dye circulation
loop.
The fabric storage tank 1 also has a holed top wall which is spaced from the
liquid/air separation plate 19 to define an interior space of the fabric
storage tank 1 for
receiving the fabric 2 therein. The holed top wall also defines an interior
spaced
CA 02288214 1999-10-25
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with the underside of the distribution tube 12 to allow air that is separated
from the
dye or that flows from the directing nozzles 121 as downstream air stream
toward the
downstream outlet 112 of the fabric guide tube 11 and into the fabric storage
tank 1 to
be collected therein and conducted by an air return tube 161 to a blower 16.
The air
is then pressurized by the blower 16 and transported through a heat exchanger
154 to
be conveyed into the distribution tubel2 via an air conveyor tube 162. As
described
above, the pressurized air that is conveyed into the distribution tube 12 via
the air
conveyor tube 162 is distributed over the plurality of directing nozzles 121
to generate
downstream air streams under the fabric 2. The base 13 of the fabric guide
tube 11
also serves to constrain the direction of the air streams and to "rebound" a
portion of
the air streams that collides the fabric 2 and is reflected toward the base 13
by the
fabric 2 so as to more effectively support the fabric 2 above the flat base
13.
A by-pass tube 165 is provided between the dye conveyor tube 152 and the air
conveyor tube 162. Valves 155, 166 and 163 are respectively provided on the
dye
conveyor tube 152, the by-pass tube 165 and the air conveyor tube 162 in such
a
manner that the circulation of fluid in the dye conveyor tube 152 may be
selectively
directed to the air conveyor tube 162 via the by-pass tube 165. The
disposition of
the by-pass tube 165 is to provide a more effective dyeing operation on the
fabric 2,
especially fabric having a greater unit weight, such as fabric having a unit
weight of
600 grams per yard length.
The disposition of the by-pass tube 165 to partially direct the fluid
circulating
inside the dye conveyor tube 152 to the directing nozzles 121 of the
distribution tube
12 via the air conveyor tube 162 is also to perform an effective rinsing
operation in
which fresh water or other suitable rinsing agent takes place of the dye in
the
circulation loop defined by the dye return tube 151, the pump 15, the filter
153, the
heat exchanger 154, the dye conveyor tube 152, the spray nozzles 14, the
fabric guide
tube 11 and the fabric storage tank 1 and is pumped to spray onto the fabric 2
from the
upper side of the fabric 2 to carry out the rinsing operation. The fresh water
is also
conducted to the distribution tube 2 to be injected to the lower side of the
fabric 2
through the directing nozzles 121. This enhances the removal of un-wanted
particles
or impurities from the fabric 2.
The fluid circulation of the dyeing apparatus of the present invention
described
above is substrantially the same as the conventional dyeing apparatus.
It should be particularly noted that the directing nozzles 121 that are
disposed
on the bottom 13 of the fabric guide tube 11 may also be replaced with nozzles
of
other designs. In accordance with the present invention, a preferred structure
for the
directing nozzles is shown in FIGS. 11 and 12, which comprises a movable blade
12101, a link bar 122, a driving rod 123. The movable blade 12101 has two
opposite
CA 02288214 1999-10-25
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pivot pins 12102 pivotally received in bushings 1101 fixed within an opening
formed
on the base plate 13 of the fabric guide tube 1 to have the blade 12101 to
define a
spacing with an edge of the opening, which spacing is adjustable by rotating
the blade
12101 relative to the base plate 13. The adjustable spacing serves as the
directing
nozzle 121. One of the pivot pins 12102 of the movable blade 12101 is extended
outward and coupled to one end of the link bar 122. The other end of the link
bar
122 is pivoted to the driving rod 123 which extends in the direction of the
fabric guide
tube 11. By connecting the link bar 122 of each of the directing nozzles 121
to the
driving rod 123, the directing nozzles 121 may be adjusted simultaneously by
moving
the driving rod 123 to rotate the blades 12101. The driving rod 123 may be
coupled
to any suitable power device, such as hydraulic actuation system, electric
motor
actuation system or other power actuation system to be driven thereby for
rotating the
blades 12101 in controlling the size of the nozzles 121 and adjusting the jet
from the
nozzles 121, FIGS. 6 and 7 show more detailed drawings of the nozzle. Further
description of the nozzle may be obtained from Taiwan patent No. 89941.
Chinese
utility mode No. ZL 93209236.5, Chinese paten application No. 93105099.5 and
U.S. Pat. No. 5,381,678.
The feature of the present invention resides in the structure of the fabric
guide
tube 11 which does not have a narrow nozzle at the upstream inlet that is
adapted in
the prior art design as indicated at All and A12 of FIGS. 1-3, and the throat
of the
prior art design through which the fabric passes indicating at A22 of FIGS. 3
and 4.
The fabric guide tube 11 of the present invention comprises a flat and wide
bottom(support plate)extending from the upstream inlet 111 to the downstream
outlet
112 and having a width sufficient to allow the fabric to fully expanded
breadthwise so
that the fabric is in a fully expanded condition in moving through the fabric
guide
tube 11 and thus allows a more efficient dyeing operation to be performed
thereon
wherein the dye sprays from the spray nozzles 14 located above the fabric may
uniformly fall onto the whole breadth of the fabric 2 from the upper side of
the fabric
2. During the movement of the fabric 2 through the fabric .guide tube 1 l, the
dye
that is sprayed onto the upper side of the fabric 2 penetrates through the
thickness of
the fabric 2 due to gravity and capillarity of the fiber composed of the
fabric 2. The
penetration of the dye through the fabric 2 effects dyeing of the fabric 2.
The lower side of the fabric 2 is subject to the air streams from the
directing
nozzles 121 so as to be floated over the bottom(support plate) 13 of the
fabric guide
tube 11 and be driven downstream by being impacted by the air streams. The
high
speed of the air streams under the fabric 2 also creates a lower pressure
condition in
which the pressure is lower than that above the fabric 2 in which the speed of
air flow
is much smaller. The difference in pressure between the lower side and the
upper
CA 02288214 1999-10-25
14
side of the fabric 2 is in an un-stable condition due to the air streams from
the
directing nozzles 121 which, in general, are not precisely uniformly
distributed along
the length of the fabric guide tube 11 so that the fabric 2 which is fully
expanded in
moving through the fabric guide tube 11 is subject to a cyclical and violent
up-and-
down vibration. The higher pressure above the fabric 2 also forms a constraint
to the
air streams under the fabric 2 to force the air streams to flow partially
breadthwise of
the fabric 2(namely in the axial direction of the dyeing apparatus.). Such a
breadthwise flow of air enhances and maintains the breadthwise expansion of
the
fabric 2 in moving through the fabric guide tube 11.
When the fabric 2 exits the fabric guide tube 11 at the downstream outlet 112,
it
is subject to the reciprocal movement of the fabric folding plate 17 which is
pivoted to
the fabric guide tube 11 at the outlet 112 and controlled to swingingly
reciprocate and
oscillate about the pivot and is sized to exercise a large area contact with
the fabric 2
when the fabric 2 is moved into the fabric storage tank 1. Due to the
oscillation of
the plate 17 about the pivot thereof, the plate 17 gets into contact with
fabric 2 in a
periodical manner and the contact engagement between the plate 17 and the
fabric 2
folds the fabric 2 in a direction opposite to the moving direction thereof so
that a
snugly folded configuration of the fabric 2 may be obtained when the fabric 2
moves
into the fabric storage tank 1.
The dye that is carried by the fabric 2 into the fabric storage tank 1 is
separated
therefrom by being driven by gravity to pass through the liquid/air separation
net 19
and collected at the lowermost portion of the fabric storage tank 1. The air
that is
moved with the fabric 2 from the fabric guide tube 11 into the fabric storage
tank 1
flows through the upper side holed plate of the fabric storage tank 1 to be
collected
and conveyed to the blower 1. Except a minor portion of the air which is
allowed to
flow to the laterally front side of the dyeing apparatus form pressure balance
purpose,
the air is collected and re-circulated by being drawn away by the blower 16
via the air
conveyor tube 161. The air is compressed and sent to the distribution tube 12
to be
jetted through the directing nozzles 121 for driving the fabric 2 downstream.
In accordance with Bernoulli's law which states that the higher the speed of a
fluid is, the smaller the static pressure it has, the high speed air streams
under the
fabric 2 creates a high speed and low pressure zone under the fabric 2 which
has a
pressure lower than that above the fabric 2. The pressure difference between
the
upper and lower sides of the fabric 2, together with gravity of the fabric 2
and the dye
carried thereon, tends to force the fabric 2 toward the high speed air stream
zone.
This causes a tight contact between the fabric 2 and the high speed air
streams and
thus increases the momentum transferred form the air streams to the fabric2 to
increase the kinetic energy of the fabric 2. However, the stream lines of the
air
CA 02288214 1999-10-25
IS
streams under the fabric 2 limits further movement of the fabric toward the
bottom 13
of the fiber guide tube 11 so as to floatingly support the fabric 2 on the air
streams and
prevent the fabric 2 from getting into directly contact with the bottom 13 of
the fabric
guide tube 11. Once the fabric 2 is forced to get closer to the bottom 13 by
means of
the pressure difference across the fabric 2, the air streams are temporarily
stopped or
"dragged" by the increased shear force between the fabric 2 and the air
streams. The
energy of the air streams is then converted to a resistance force against the
movement
of the fabric 2 toward the bottom 13 and rebound the fabric 2 away from the
bottom
13. This causes a cyclic vibration(up and down movement) of the fabric 2
inside the
fabric guide tube 11. The frequency of the vibration of the fabric 2 is, of
course,
dependent upon the unit length weight of the fabric and the momentum
transferred by
the air streams, as well as other factors that are known to those skilled in
the field of
fluid dynamics. Thus, such a vibration may be, at least partially, controlled
by
adjusting the opening size of the directing nozzles 121 or by changing the
power input
to the blower 16.
The cyclic vibration of the fabric involves a massive transfer or conversion
of
energy which causes the fibers of the fabric 2 to become loosened, thus
enhancing the
penetration of the dye into the fabric 2 and increasing the absorbability and
diffusion
of the dye within the fabric 2 so that besides increasing the moving speed of
the fabric
2 and providing a dyeing operation with a small quantity of dye, high
concentration,
high e~ciency, low energy consumption, low bath ratio and low pollution, the
present
invention helps to loosen the fibers within the fabric so as to enhance the
removal of
un-wanted matters or impurities from the fabric, increasing the operation
efficiency of
for example rinsing, cleaning, bleaching and thus increase the overall
efficiency of the
dyeing operation.
Although preferred embodiments have been described to illustrate the present
invention, it is apparent that changes and modifications in the specifically
described
embodiments can be carried out without departing from the scope of the
invention
which is intended to be limited only by the appended claims.
