Device for applying a film of liquid film to a web of goods

A device for applying a laminar flowing liquid film of considerable width, the film being uniformly thin over the working width, to a continuously advanced web of goods includes a liquid distribution device supplied with liquid fed by a pump and provided with a plurality of liquid distribution chambers and an associated guide surface from which the liquid film flows onto the web of goods. The liquid distribution chamber is connected by a supply line with the pump and the guide surface extend over a working width greater than the cross section the of supply line. Each liquid distribution chamber extend only over an exactly defined working width which is narrow by comparison with the width of the wider web of goods, and each chamber is connected with only one liquid supply line.

BACKGROUND OF THE INVENTION 
This invention relates to a device for applying a laminar flowing film of 
liquid, uniformly thin over a working width of the device, to a 
continuously advanced web of goods which includes a liquid distributing 
device supplied with liquid fed by a pump, with a liquid distribution 
chamber and an associated guide surface possibly provided with an overflow 
weir, from whose lower edge the film of liquid runs onto the web of goods 
e.g. textile goods including woven and non-woven materials, as it flows 
away; said liquid distribution chamber being connected by a supply line 
with the pump and extending toward the guide surface over a working width 
that is made greater than the cross section of the supply line. 
A device of this kind is known from DE 35 22 320 A1 and corresponding U.S. 
Pat. No. 4,656,845. This device has the advantage that it allows a fast 
change of the application liquid, e.g. dye, colorant or the like, in terms 
of its nature or color, without the previously necessary downtime or 
production of reject materials from the web of goods to be wetted, with 
uniform distribution and constant quantity of application liquid over the 
working width being ensured. This is brought about by a liquid supply 
chamber connected upstream from the overflow edge, which opens out in a 
conically expanding fashion toward the overflow weir, but is small in 
volume. In this manner, the contact of the liquid supply stream which is 
necessary to form a laminar liquid film flows up to the overflow weir. In 
such a device the liquid feed flow must be calmed because the liquid 
volume within this liquid supply chamber is very small while the amount of 
liquid to be applied over the working width of more than 30 
liters/min/meter of the working width is very great and hence the inflow 
of the liquid into this device, divided between several supply lines, is 
very strong. 
Upstream of the liquid supply chamber of the device according to the 
above-mentioned disclosure document, a liquid distribution chamber is 
located which extends over the entire working width in the exact same 
fashion as the overflow weir. The liquid distribution chamber has supply 
lines associated with it. The liquid flowing in through these lines is 
distributed in the distribution chamber by a plurality of baffles or 
partitions over the working width. Work with a device of this kind has 
shown that it does provide a rapid color change, but during the transition 
between one color and the next, an area, albeit small, is produced on the 
web of goods in which the colors mix with one another, especially in the 
form of tongue-shaped mixtures of color in the spaces between the 
individual feed lines. 
SUMMARY OF THE INVENTION 
The goal of the invention is to develop a device in which, with the same 
range of goals for rapid color change and low liquid volume in an 
application device with the advantageous pouring principle, a linear color 
change is now made possible and the previously necessary volume of liquid 
within the device can be further reduced. 
Taking its departure from the device of the type recited heretofore, the 
solution to the stated problem consists in the fact that the liquid 
distribution chamber extends over only a precisely defined working width 
which is narrow by comparison to the width of a wide web of goods and this 
chamber is connected with only one liquid supply line. Since in this 
working area a device is used which must distribute the liquid over a web 
of goods with a large working width, a plurality of these liquid 
distribution chambers is arranged side by side and can then cover the 
entire working width of the web of goods. Hence, the goal of the device 
according to the invention is to calm and to distribute laterally the 
liquid flowing through the feed line in the limited liquid distribution 
chamber, in such fashion that when the color is changed, no stripes 
composed of mixed colors will result, so that after this uniform 
distribution, the liquid can be allowed to flow directly to the overflow 
weir or even to the guide surface. Hence, there may no longer be any need 
for the distribution chamber required in the above-mentioned disclosure 
document, so that the liquid volume required in the application device can 
be kept much smaller. 
The distribution of the liquid within this liquid distribution chamber of 
limited width takes place in stages and uniformly, to each individual 
liquid outflow opening. This uniform distribution is made possible by 
connecting a branch line of the same length from the liquid supply opening 
on both sides in the direction of the working width, the branch line 
having an intermediate outflow opening at the end. This intermediate 
outflow opening in turn has a corresponding branch, but with outflow 
openings located closer together, resulting in branching resembling the 
branches of a tree. Since distribution necessarily takes place uniformly 
as a result of this tree-like branching, the liquid is always uniformly 
distributed over the plurality of outflow openings. 
One especially advantageous design for connecting the liquid distribution 
chamber with the tree-like branches for the liquid from the supply opening 
to the plurality of liquid outflow openings consists in extending the 
branch lines in the direction of the working width, so that the 
intermediate outflow openings connected to these branch lines can be made 
in the form of holes in correspondingly thin sheets. It is therefore 
especially advantageous to fill the liquid distribution chamber with a 
plurality of such sheets and to arrange the branch lines and holes made in 
these sheets in accordance with a certain program in such a way with 
respect to one another that the result is a uniform, tree-like branching 
of the lines from the feed line to the plurality of outflow openings 
associated with the overflow weir or directly with the guide panel.

DETAILED DESCRIPTION OF THE INVENTION 
The liquid application device according to FIG. 1 consists of an angle 
support 1, whose 90.degree. corner is pointed upward. One leg of the angle 
support is a partition 2, aligned diagonally upward in the direction of 
overflow weir or edge 3. Guide surface 4 abuts overflow weir 3, over which 
a uniformly distributed liquid film runs and flows onto the web of goods 5 
guided along beneath it. A web of goods 5 is supported with the nap 
located upwardly over a reversing roller 6. On the side opposite partition 
2, a solid body or liquid application rail 7 ias located whose wall facing 
partition 2 serves as a diffuser wall 8. This wall 8, however, can also be 
aligned parallel with partition 2, forming a slot 9' as a supply chamber 
as shown in FIG. 5. Between the upwardly directed diffuser wall 8 and 
partition 2, supply chamber 9 is formed (as shown in FIG. 1), expanding 
conically toward overflow edge 3. The supply chamber, however, can also 
take the form of a slit without a cone, as shown in FIG. 5. Body 7 extends 
together with the other parts of dye application device 1 over a working 
width up to 6 meters wide and is provided over this working width with 
only a few supply hoses 10 through which the necessary quantity of liquid 
is fed to the application device by means of a pump, not shown. The device 
shown thus corresponds in certain aspects to that shown in DE 35 22 320 
A1. 
An essential feature of the device shown here is the liquid distribution 
system located in body 7. Hose 10 is pushed over a mouthpiece or fitting 
11 mounted in body 7 in the vicinity of 12 and has its lower end screwed 
into the liquid distribution device 13. The liquid distribution device can 
also be aligned parallel to partition 2 as shown in FIG. 5, and not 
perpendicular to the partition. This liquid distribution device 13 is 
shown in detail in FIGS. 2 and 3. It consists of a plurality of panels 14 
arranged parallel to one another and pressed together after assembly. Only 
one hole is provided in the uppermost panel 15 of this liquid distribution 
device 13, said hole forming liquid supply opening 16 of a liquid 
distribution chamber limited to the working width according to FIGS. 2 and 
3. A plurality of these liquid distribution chambers are arranged side by 
side over the working width of the entire application device. According to 
FIG. 2, from each of the liquid supply openings 16, associated with a hose 
10, a liquid distribution system extends to the lower side of the 
individual liquid distribution devices 13 which extend over an exact 
working width; said width, however, being only a fraction of the total 
width of the application device. 
Distribution of the liquid flowing in through a feed opening 16 takes place 
in the liquid distribution chamber, which is filled with individual panels 
14. In the embodiment shown, this distribution chamber has eight panels 14 
arranged parallel to one another, so that the liquid flowing through 
supply opening 16 is distributed among a total of 16 liquid outflow 
openings 17. This is because the width distribution of the liquid is 
forced in stages from panel to panel. For this purpose, branch lines 18 
and 19 of equal length are provided on both sides of liquid supply opening 
16 in the direction of the working width, in FIG. 2 both to the right and 
to the left, with an intermediate outflow opening 20, 21 being provided at 
each end of said lines. These two intermediate outflow openings 20, 21 are 
drilled in a panel 14 located below. These two intermediate outflow 
openings 20, 21 are joined in turn in the same fashion on both sides in 
the direction of the working width, to branch lines 22, 23 which are half 
as long, so that liquid distribution takes place like the branches of a 
tree or the antlers of a deer. This distribution takes place precisely 
uniformly over the working width. In order not to have to install too many 
hoses 10 over the entire working width, approximately 10 to 20 of the 
liquid outflow openings 17 should have a mutual spacing of about 10 mm to 
one of these liquid distribution chambers. 
Since the liquid flowing in liquid supply opening 16 has to be distributed 
over a plurality of liquid outflow openings 17, the cross sections must be 
reduced in stages from this liquid supply opening 16 to liquid outflow 
openings 17. This is shown in FIG. 3. The cross section of the 
intermediate outflow openings 20, 21 that follow liquid supply opening 16 
is cut in half, and the associated branch lines 20, 23 are accordingly 
made narrower in cross section than 18 and 19 above. 
It has already been stated that the liquid distribution device is formed 
from a plurality of panels 14 arranged parallel to one another, each of 
said panels having either an intermediate outflow opening 20, 21 or a 
branch line 18, 19, 22, 23. To produce this dendriform branching of the 
liquid, holes 20, 21 are provided in the individual panels and branch 
lines 18, 19, 22, 23 are provided as holes at points such that the 
dendriform branching shown in FIG. 2 results after assembly. 
Division of the entire working width of 1 to 5 meters into areas 
corresponding to a liquid distribution chamber like that shown in FIG. 2 
has the advantage that the liquid supplied through hoses 10 can be 
distributed exactly uniformly over a considerable working width. Depending 
on the working width of web of goods 5, it is then possible, by switching 
off individual supply hoses 10, to define the effective working width of 
the dye application device. A more important advantage, however, is to be 
able to force uniform distribution of the dye liquid over the working 
width without having to use a common supply chamber extending over the 
working width. The liquid which now emerges uniformly from liquid outflow 
openings 17 collects only in abutting connecting slot 24 which now extends 
over the entire working width of the web of goods. A pressure develops 
there because at this connecting slot 24 there is a liquid outflow slot 25 
which likewise extends over the working width, the throughput height of 
said slot being less than the depth of connecting slot 24. It will be seen 
that the last panel or sheet 26 extends over the entire length of the 
application rail and that a plurality of the distribution devices 13 is 
arranged side-by-side over the application rail. 
From liquid outflow slot 25, the liquid flows uniformly and is distributed 
over the working width, out of liquid distribution device 13. 
Consequently, liquid supply chamber 9 shown in FIG. 1 is only 
conditionally necessary. This advantage is made clear in FIG. 4. Here each 
liquid distribution device 13 has associated with it only one guide 
surface in the form of a guide panel 27, by which the liquid, uniformly 
distributed over the working width by liquid distribution device 13, flows 
onto web of goods 5. In simple fashion, connecting slot 25 is formed 
between panel 26 of connecting slot 24 and guide panel 27. In this 
embodiment therefore, not only is solid body 7 with liquid supply chamber 
9 eliminated, but also overflow edge 3 together with angle support 2; 
instead, only guide panel 27 is required to guide the uniformly 
distributed liquid onto the web of goods 5. This considerably reduces the 
volume of liquid constantly being fed to distribution device 13, and even 
to the application device as a whole, resulting in the desired rapid color 
change. In this embodiment, just as in the other embodiments, the panel 26 
is attached to the uppermost sheet or panel 15 by screws (not shown).