Apparatus for applying foamed treating liquor

Apparatus particularly adapted for applying foamed treating liquor to a flat width of a traveling non-woven textile substrate includes a longitudinal tubular foam distribution nozzle one side of which has a plurality of closely-spaced staggered apertures for engaging and applying pressurized foam widthwise across the substrate and a driven drum opposed to the nozzle engaging widthwise the opposite side of the substrate for imparting traveling movement to the substrate. The drum and nozzle cooperate to compress the substrate therebetween in covering relation over the apertures to prevent lateral escape of the foam therefrom and to confine the emission of foam therethrough, thereby to uniformly control foam application across the substrate width as it travels by the nozzle. Limited contact of the apparatus with the substrate prevents frictional pulling and structural damage thereto. The drum is perforated for escape of the air component of the foam and to enhance foam penetration of the substrate. If desired, one apparatus may be employed to achieve full substrate penetration or two serial apparatus may be arranged to treat respectively opposite substrate sides for full penetration.

BACKGROUND OF THE INVENTION 
The present invention relates generally to apparatus for applying foamed 
treating material and more particularly to such apparatus for applying 
foamed treating liquor to a flat width of traveling textile substrate of 
the non-woven, non-knitted type. 
Various apparatus are known for applying foamed treating liquor to a flat 
width of a traveling textile material of knitted or woven type, examples 
of such apparatus being disclosed in Clifford and Zeiffer U.S. Pat. No. 
4,237,818, and Clifford and Turner U.S. patent application Ser. No. 
299,533, filed Sep. 4, 1981, both commonly assigned herewith. Typically, 
such apparatus employs some form of foam applicator across which the 
textile material is pulled by driven rollers, which is inappropriate for 
use in applying treating liquor to textile materials of the non-woven, 
non-knitted type (hereinafter referred to generically by the common 
industry term "non-woven" to designate any sheet-like or web material 
bonded together substantially only by cohesive forces) which materials 
lack the structural integrity to resist structural damage thereto by the 
pulling action exerted thereon by the driven rollers of such apparatus. 
Accordingly, special apparatus is necessary for the liquor treatment of 
non-woven materials. Presently, the apparatus available for this purpose 
employs moving screens or belts of open-work or other permeable 
construction on which a non-woven web is transported to and from a liquor 
applicator which is arranged to spray the desired liquor on the web. 
Several operational and environmental disadvantages are inherent in the 
use of this type of apparatus. As will be understood, the liquor employed 
in many cases is a binder or a resin which will necessarily be oversprayed 
on and adhere to the belt or screen impairing its flexibility and 
permeability and, in some cases, causing difficulty in the proper tracking 
of the belt or screen. Further, the spraying technique, even under 
conditions of overspraying of the treating liquor, generally is 
ineffective to achieve a desired degree of penetration of the treating 
liquor into the web and, for this reason, it is customary to perform the 
spraying operation twice respectively to each side of the web or to apply 
a vaccuum force through the belt to draw the sprayed liquor into the web. 
As will be understood, the spraying technique inherently creates a 
contaminated atmosphere in the vicinity of the applicator and thereby 
poses a health hazard. Further, the oversprayed liquor which accumulates 
on the belts and screens and otherwise in the vicinity of the applicator 
must periodically be washed from the surfaces affected, creating waste 
water treatment problems. As will be understood, all of these problems 
contribute to substantially increase the capital investment and 
operational costs in performing such non-woven treating operations. 
In contrast, the present invention provides an apparatus for applying 
foamed treating liquor to a non-woven textile substrate by which the 
substrate is contactingly engaged by and compressed against an applicator 
nozzle for uniform application to and penetration into the substrate of 
the liquor without significant emission of liquor into the surrounding 
atmosphere or the adherence thereof onto any operational element of the 
apparatus and, further, without structurally damaging the substrate. 
SUMMARY OF THE INVENTION 
Briefly described, the present apparatus for applying foamed treating 
liquor to a flat width of traveling substrate includes an applicator 
nozzle having a flat longitudinal substrate engaging surface disposed to 
extend transversely across the substrate width in direct surface contact 
compressively with one side thereof and a rotatably driven cylindrical 
drum axially disposed substantially parallel and in opposition to the 
nozzle engaging surface transversely across the width of the opposite side 
of the substrate in peripheral surface contact compressively therewith for 
drivingly engaging the substrate to impart movement thereto in its 
direction of travel. The nozzle has formed internally thereof a foam 
distribution chamber communicating with a pressurized foamed liquor 
generator and includes a plurality of closely-spaced apertures extending 
between the chamber and the engaging surface along the length thereof for 
emitting foamed liquor for application to the one side of the substrate. 
The drum and the nozzle cooperate to compress the substrate against the 
nozzle engaging surface in covering relation to the apertures sufficiently 
to prevent escape of the foamed liquor laterally across the substrate 
engaging surface between it and the substrate and to confine the emission 
of foamed liquor through the apertures to the substrate for controlled 
application of said foamed treating liquor to the one side of the 
substrate and, in this manner, the foamed liquor is applied uniformly to 
the one side of the substrate across its width and length as it travels 
past the nozzle. 
In the preferred embodiment, the nozzle includes a tubular member forming 
therewithin the distribution chamber and having at least one flat side 
forming the substrate engaging surface in which the apertures are formed. 
The apertures are arranged along the nozzle in two staggered linear rows 
the respective apertures of which staggeringly overlap in the direction of 
substrate travel to collectively apply the foamed liquor across the entire 
widthwise extent of the substrate. Further, the apertures are outwardly 
flared to the engaging surface to increase the area of application to the 
substrate of each aperture. The substrate engaging surface is of a 
relative small extent in the direction of substrate travel for limiting 
contact therewith to reduce frictional resistance to the traveling 
movement of the substrate. 
The drum is indentedly relief-formed about its peripheral surface for the 
escape of the air content of the foamed liquor through the substrate into 
the indentations thereby to enhance the penetration of the substrate by 
the liquor. Preferably, the drum is hollow with a perforated periphery 
having plural axially-extending linear rows of closely-spaced, staggered, 
outwardly-flared apertures about the entire peripheral surface of the 
drum. The arrangement for rotatably driving the drum provides for the 
control of the rotational speed thereof for controlling the quantity of 
the foamed liquor applied to the substrate per unit area thereof. 
The preferred embodiment also includes a pair of pneumatically actuated and 
connected piston and cylinder assemblies on which the nozzle is mounted 
for movement toward and away from the drum thereby for biasing the nozzle 
toward the drum to provide the compressive force exerted therebetween on 
the substrate. 
If desired, a second liquor-applying apparatus of like construction may be 
provided sequentially following the above-described first apparatus, the 
first apparatus having the substrate engaging surface of its nozzle 
arranged to engage the one side of the substrate with the drum of such 
first apparatus engaging the opposite side of the substrate and the second 
apparatus having the substrate engaging surface of its nozzle arranged to 
engage such opposite side of the substrate with the drum of such second 
apparatus engaging the one side of the substrate, whereby the two 
apparatus respectively apply said foamed liquor to the opposite sides of 
the substrate for complete penetration thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the accompanying drawings, the apparatus of the present 
invention is herein illustrated and described in its preferred embodiment 
for applying a foamed aqueous-based binder to the opposite sides of a 
traveling web of non-woven batting; for example, fiberglass batting such 
as is employed for insulating purposes. However, it will be understood 
that the present invention is equally applicable for use with a wide 
variety of other materials as well. In the accompanying drawings, the 
apparatus for applying foamed treating liquor according to the present 
invention is illustrated in two forms incorporated respectively in two 
treating machines, indicated generally at 10 and 12, serially-arranged as 
successive stations in a substrate treating range through which the 
substrate travels in a horizontal, linear path widthwise parallel to 
horizontal as a flat width of traveling substrate S. An appropriate 
transport device 14 is arranged following the liquor applying machines 
10,12 and includes oppositely driven nip rollers 16 to engage the treated 
substrate S and convey it to the following station in the treating range. 
Such transport devices 14 are known and form no part of the present 
invention and, accordingly, will not be described herein. 
The machines 10,12 are of substantially similar construction and operation, 
including identical components, and, accordingly, the description thereof 
hereinis considered applicable to each machine 10,12 except as the 
particular differences of the machines 10,12 are specifically indicated 
hereinafter. Like reference numerals are employed for the corresponding 
components of each machine 10,12. 
Each machine 10,12 has a supporting frame 18 on which the liquor-applying 
apparatus of the present invention and the other operative components of 
the machine are operatively mounted. The frame 18 includes an opposed pair 
of upstanding end frame members 20 rigidly joined at their lower ends by 
an appropriate cross member base framework generally indicated at 21 and 
at their upper ends by cross-members 23 at a sufficient spacing to permit 
the substrate S to pass between the end frame members 20. A control panel 
19 in which may be housed appropriate machine control mechanisms, gauges 
and the like is mounted on one end frame member 20 of each machine 10,12. 
The liquor applying apparatus of the machines 10,12 are indicated 
respectively at 22,24. Each apparatus 22,24 includes a foamed liquor 
applicator nozzle 26 and a driven cylindrical drum 28 respectively mounted 
to extend horizontally between the end frame members 20 of the machine in 
opposed facing disposition transversely across the path of travel of the 
substrate S on opposide sides thereof for passage of the substrate S 
therebetween for application of the foamed treating liquor thereto by the 
nozzle 26. In the liquor applying apparatus 22 of the machine 10, the 
nozzle 26 is disposed above the path of the substrate S with the drum 28 
disposed therebelow for application of the treating liquor to the upwardly 
facing surface of the substrate S while, in the liquor applying apparatus 
24 of the machine 12, the nozzle 26 is disposed below the path of the 
substrate S with the drum 28 disposed thereabove for application of the 
treating liquor to the underside of the substrate S. 
Each drum 28 of the liquor applying apparatus 22,24 of the machines 10,12 
includes a pair of spoked, circular end hubs 30 spaced apart in co-axial 
relation and between which are intermediately disposed spacedly in coaxial 
relation therewith several circular supporting rings (not shown) of equal 
diameter, a perforated or otherwise indentedly relief-formed sheet of 
stainless steel 32 being bent circumferentially about the rings and hubs 
30 and fixedly joined thereto to form the cylindrical outer surface of the 
drum 28. An axial shaft 34 extends centrally through each drum 28, through 
the axial center of its end hubs 30 to which the shaft 34 is fixedly 
joined, and axially outwardly of the drum 28 therefrom. The end frame 
members 20 of each machine 10,12 are provided with corresponding, aligned 
vertical slots 36, the drum 28 of each machine 10,12 extending 
horizontally between the end frame members 22 thereof with the outwardly 
extending end portions of the shaft 34 extending respectively through the 
slots 36 and mounted respectively in appropriate bearing assemblies 38 
affixed to the outward sides of the end frame member 20 at a location 
spaced from the path of the substrate S an appropriate distance to dispose 
the drum 28 for rotation substantially peripherally tangential to the path 
of the substrate S. As will be understood, the drum 28 of the machine 10 
is so mounted upwardly in the slots 36 of the end frame members 20 thereof 
for peripherally tangential engagement of the upward side of the substrate 
S, while the drum 28 of the machine 12 is so mounted downwardly in the 
slots 36 of the end frame members 20 thereof for peripherally tangential 
engagement of the underside of the substrate S. 
A variable speed electric motor 40 of any conventional construction 
appropriate for rotatably driving a drum 28 is mounted on each machine 
10,12 at the upper end of one of its end frame members 20 with the drive 
shaft 40' of the motor 40 extending outwardly of its machine 10,12 beyond 
such end frame member 20 in parallel relation to the shaft 34 of the drum 
28 of the machine. The shaft 34 of the drum 28 of each machine 10,12 has a 
sprocket 42 rigidly affixed to the end thereof which extends outwardly of 
the end frame member 20 on which the motor 40 is mounted and the drive 
shaft 40' of the motor 40 is provided with a similar sprocket 44, an 
endless timing chain 46 being trained about the sprockets 42,44 to impart 
rotation of the electric motor drive shaft 40' to the shaft 34 of the drum 
28 to rotate the drum 28 peripherally tangentially to the substrate S in 
the same direction of travel thereas. For safety purposes, each machine 
10,12 is provided with an emergency drum stop switch 81 actuated by 
depression thereagainst of a bar 82 which extends across the full width of 
each side of each machine 10,12 and is thereby operative to stop the 
electric motors 40 to prevent rotation of the drums 28 whenever a bar 82 
is contacted and depressed, thereby to reduce any likelihood of accidental 
injury by insertion of an operator's hand, arm or piece of clothing into 
the area of the nip between the nozzle 26 and drum 28 of either machine 
10,12. 
Each applicator nozzle 26 includes a length of a flatsided, 
cross-sectionally square metal tubes 48 the ends of which are sealed by 
end plates 50 appropriately bolted thereto. The hollow central cavity of 
the tube 48 thus provided forms a foam distribution chamber 52. In one 
surface 48' of the tube 48 are formed foam inlet openings 54 adjacent the 
ends of the tube 48 and a closeable foam outlet opening 56 intermediately 
thereof, the foam inlet openings 54 being connected by appropriate 
conduits 58 to a foam generating apparatus (not shown) which may be of any 
conventional construction but is preferably of the type disclosed in the 
aforementioned U.S. Pat. No. 4,237,818, and the outlet opening 56 being 
connected by a conduit 60 to a waste liquid recovery tank (not shown) or 
other suitable recovery arrangement. In the opposite surface 48" of the 
tube 48, which forms a substrate engaging surface, is formed a plurality 
of apertures 62 extending between the distribution chamber 52 and such 
surface 48" along the length of the tube 48 for emitting foamed treating 
liquor for application to the substrate S. To permit the use of the 
machines 10,12 for treating substrates of differing widths, an appropriate 
aperture-covering slide arrangement or the like may be provided in each 
end of each nozzle 26 for selectively covering some of the apertures 62 
thereof to prevent communication therethrough from the distribution 
chamber 52 to the surface 48" thereof for varying selectively the 
longitudinal extent along each nozzle 26 of operative, open apertures 62 
as may be necessary to conform the effective width of the nozzles 26 to 
substrates of differing widths. An angled guide plate 63 is affixed to 
each opposite side 48'" of each tube 48 to guide the substrate S to and 
from the nip between the nozzle 26 and the drum 28 of each machine 10,12. 
The tube 48 of each applicator nozzle 26 is of a selected length sufficient 
to extend between the end frame members 20 of its respective machine 
10,12. As best seen in FIG. 7, an angle bracket 64 is bolted by one leg 
64' thereof to the inward side of each end frame member 20 along each edge 
of the slot 36 thereof and each angle bracket 64 has affixed to the free 
leg 64" thereof a bearing block 66 which extends therefrom inwardly of the 
slot 36. The applicator nozzle 26 of each machine 10,12 is disposed to 
extend horizontally between the end frame members 20 thereof on the 
opposite side of the path of the substrate S from the drum 28 of its 
machine 10,12 with the apertured surface 48" of the nozzle 26 facing the 
substrate S and with the ends of the nozzle 26 extending respectively into 
the slots 36 and engaged on opposite sides by the bearing blocks 66 
thereat. (See FIG. 7). In the machine 12, two cross member plates 68 of 
the frame 18 extend transversely between the cross members 23 at equal 
inward spacings respectively from the end frame members 20 and the cross 
member plates 68 support respectively thereon two conventional 
pneumatically-operated piston and cylinder assemblies 70, the pistons 72 
of which extend downwardly through the cross member plates 68 and are 
affixed to the surface 48' of the nozzle 26 of the machine 12 to support 
it in the above-described disposition. Similarly, in the machine 10, two 
piston and cylinder assemblies (not shown) are supported on appropriate 
frame members of the base framework 21 of the frame 18 below the substrate 
path and the pistons thereof extend upwardly and are affixed to the side 
48' of the nozzle 26 of the machine 10 to support it in the 
above-described disposition. 
The pneumatically-operated piston and cylinder assemblies are commonly 
connected operatively by a conduit 73 to a conventional source of 
compressed air and the assemblies will thus be understood to provide for 
selective movement of each applicator nozzle 26 of the machines 10,12 
toward any away from its associated drum 28 by the opening and closing, 
respectively, of the conduit 73 to communication with the compressed air 
source, the purpose of which will be hereinafter more fully described. 
Preferably, the piston and cylinder assemblies are of the construction 
illustrated in FIG. 4, including a hollow cylindrical housing 74 in which 
an expansible diaphragm 76 is sealably mounted at one end thereof with the 
piston 72 joined to the diaphragm 76 and extending outwardly through the 
opposite end of the housing 74. An air inlet fitting 78 is connected to 
the conduit 73 and extends sealably through the aforesaid one end of the 
housing 74 and into the confines of the diaphragm 76, whereby the 
direction of compressed air through the fitting 78 and into the diaphragm 
76 effects expansion thereof and causes the piston 72 to be reciprocated 
outwardly from the aforesaid opposite end of the housing 74. A coiled 
spring 80 is disposed about the piston 72 between the diaphragm and such 
opposite end of the housing 74 to effect return of the diaphragm 76 and 
the piston 72 upon the relief of the compressed air from the diaphragm 76. 
In this manner, the piston and cylinder assemblies are operable to exert a 
balanced force along the length of the nozzles 26 of the machines 10,12 
toward the respective drums 28 thereof for balanced compression of the 
substrate S between the drum 28 and applicator nozzle 26 of each machine 
10,12 for driving engagement of the substrate S by each drum 28 to impart 
movement thereto in its direction of travel and to confiningly cover the 
apertures 62 of each nozzle 26 sufficiently to prevent escape of the 
foamed liquor laterally from the apertures 62 and to confine the emission 
of the foamed liquor therethrough to control the application thereof to 
the substrate S, as hereinafter more fully described. 
The operation of the machines 10,12,14 will thus be understood. In starting 
up the operation of the machines 10,12, 14, the supply of compressed air 
to the piston and cylinder assemblies of each machine 10,12 is closed by 
an appropriate switch or the like (not shown) whereby the applicator 
nozzle 26 and drum 28 of each machine 10,12 are spaced apart for threading 
of the substrate S sequentially through each machine 10,12. The transport 
device 14 is similarly provided with an appropriate conventional mechanism 
for separating its nip rolls 16 for threading of the substrate S 
therethrough. The substrate S is threaded through the machines 10,12,14 by 
feeding it through the openings between the associated nozzles 26 and 
drums 28 of the machines 10,12 and through the opening between the nip 
rolls 16 of the machine 14. Thereafter the supply of compressed air is 
opened to the piston and cylinder assemblies of the nozzles 26 of the 
machines 10,12 to bring the respective applicator nozzles 26 into 
compressive engagement with the substrate S to grip it between the nozzles 
26 and their associated drums 28. As necessary, the pressure of the 
compressed air supplied to the piston and cylinder assemblies is adjusted 
in conventional manner to achieve the appropriate desired compressive 
force on the substrate S, as explained hereinafter. The nip rolls 16 of 
the transport device 14 are also brought into their operative disposition 
to grip the substrate S therebetween. With the respective outlet openings 
56 of the nozzles 26 initially open, the foam generating apparatus is 
actuated to feed foamed treating liquor under pressure through the 
conduits 54 and the inlet openings 56 of the nozzles 26 into the 
distribution chambers 52 thereof, the compressive forces exerted by the 
applicator nozzles 26 on the substrate S creating resistance to the flow 
of the foamed liquor through the apertures 62 whereby the foamed liquor 
follows a flow path of lesser resistance and exits the distribution 
chamber 52 through the outlet openings 56 into the waste liquor recovery 
tank. In this manner, the foamed liquor purges from the nozzle 
distribution chambers 52 any liquor chemicals remaining therein from 
previous use of the machines 10,12 and, further the appearance of the 
foamed liquor discharged into the recovery tank may be inspected to insure 
its appropriate desired form and any necessary adjustments in the foam 
generating apparatus are made. Once the foam appearance is satisfactory, 
the outlet openings 56 are closed and the drum motors 40 and the nip rolls 
16 of the transport device 14 are actuated to begin the ordinary operation 
of the range. 
In the operation of the machines 10,12, the piston and cylinder assemblies 
exert a uniform balanced force on the respective nozzles 26 biasing them 
toward their associated drums 28 to uniformly compress the substrate S 
between the drum 28 and the nozzle 26 of each machine 10,12 as the 
substrate S travels in its linear path under the impetus of the rotating 
drums 28. It has been found and is believed desirable that, for virtually 
any conventional non-woven web substrate of ordinary original thickness 
(e.g. one to two inches), the piston and cylinder assemblies be adjusted 
to effect compression thereof to approximately one thirty-secondth of an 
inch (1/32") to achieve desired restrictive covering of the nozzle 
apertures. Several distinct and important advantages accrue from this 
manner of operation. The action of the piston and cylinder assemblies 
compresses the substrate S with sufficient force to maintain it against 
the apertured surface 48" of the nozzle tube 48 in covering relation to 
the apertures 62 thereof against the emissive force exerted by the 
pressurized foam through the apertures 62 sufficiently to prevent 
undesired escape of the foamed treating liquor laterally across the 
respective apertured substrate engaging surfaces 48" of the nozzles 26 
between such surfaces 48" and the substrate S and to confine the emission 
of the foamed treating liquor at any given moment in the operation to the 
precise areas of the substrate S covering the apertures 62 at such given 
moment. As will be understood, the perforations 32' in the outer sheet 32 
of each drum 28 permit the escape therethrough of the air component of the 
foamed liquor which enhances the penetration of the foamed liquor into the 
substrate S. This resistive force exerted by the piston and cylinder 
assemblies thus effectively prevents any seepage of foamed liquor 
laterally from the apertures without application thereof to the substrate 
S which provides substantially uniform foam application to the substrate, 
significantly less waste of the required treating and foaming chemicals, 
as well as substantially reduced or eliminated problems of accumulation of 
such chemicals on machine parts, thereby alleviating the necessity of 
continuous washing or cleaning of the machine which is often required with 
the conventional types of apparatus noted hereinabove. 
While the foam is advantageously applied uniformly to the substrate in 
terms of a uniform width of application and a uniform force or pressure of 
foam application across the width, it is also applied uniformly in 
quantity when the substrate is of substantially uniform density. As a 
practical matter, however, some substrates are not of substantially 
uniform unit area density throughout their extent and when the present 
apparatus is used to apply foam to a substantially non-uniform density 
substrate, the foam will apply itself in greater quantity to less dense 
areas than to more dense areas because of the lesser resistance of the 
less dense areas to penetration of the foam, which loads the less dense 
areas with more foam than the denser areas. This can be a significant 
advantage when the foam is applied for the purpose of loading the 
substrate as it results in a leveling of the weight per unit area across 
the width of the ultimate foam treated substrate. But even with a 
substantially non-uniform density substrate, the foam is applied uniformly 
in terms of width of application and force or pressure of foam 
application. 
To ensure that the foamed treating liquor is applied by each nozzle 26 to 
the entire widthwise extent of the substrate S, the apertures 62 of the 
surface 48" of each nozzle 26 are arranged equally spaced in several 
linear rows, preferably two, extending along the length of the nozzle 26 
and the apertures 62 of each row are staggered relative to the apertures 
62 of the other row (or rows, if more than two rows are provided) so as to 
overlap in the linear direction of travel of the substrate S. (See FIGS. 
8-10). Further, the apertures 62 are preferably formed by countersink 
drilling such that each aperture 62 is outwardly flared at the surface 48" 
of each nozzle 26 thereby inreasing the area of application to the 
substrate S of each aperture 62. In this manner, the apertures 62 of each 
nozzle 26 collectively are substantially comparable in area and effective 
foam application to conventional nozzles of the type having a single 
longitudinal slot for foam emission therethrough and, accordingly, are 
equally effective to apply the foamed treating liquor across the entire 
widthwise extent of the substrate S. Preferably, the apertures 62 of each 
row are as closely spaced as feasible, e.g. one thirty-secondth of an inch 
(1/32") in the illustrated embodiment at the engaging surface 48" and the 
apertures of adjacent rows are staggered and arranged substantially 
tangential respectively to an imaginary line extending between the 
aperture rows, thereby to best achieve the above-described effect. 
Notably, however, the apertured nozzle 26 of the present apparatus 
provides sufficient bridging between the respective apertures 62 thereof 
to prevent significant compression of the substrate S into the apertures 
62 which would restrict the traveling movement of the substrate S across 
the engaging surfaces 48" of the nozzles 26 and thereby could cause 
tearing or other damage of the substrate S and, thus, the present 
apparatus eliminates this disadvantage attendant to slotted nozzles and 
the various conventional apparatus in which they are incorporated which 
contributes to render such apparatus unsuitable for foamed treatment of 
non-woven substrates. 
Similarly, the perforations 32' in the outer sheet 32 of each drum 28 are 
formed closely-spaced about the entire peripheral area of each drum 28, 
the perforations 32' being arranged in closely-spaced and staggered linear 
rows of countersunk holes extending axially along the length of each drum 
28 to maximize the perforated peripheral surface area of each drum 28 to 
insure adequate escape flow paths for the air component of the foamed 
liquor so as to best enhance uniformity of foam penetration into the 
substrate S. (See FIG. 11). 
Further, although the substrate S is subjected to the above-described 
compressive forces, it is not subjected to any significant pulling force 
exerted along its length which could tend to cause it to tear. The impetus 
for the traveling movement of the substrate S through the machines 10,12 
is provided by the rotational engagement of the substrate S by the 
respective drums 28 which effectively exert a pushing action on the 
compressed portions of the substrate S. Notably, at any given moment, the 
substrate S is in surface engagement with the nozzles 26 and the drums 28 
across the full widthwise extent of the substate S but to only a 
relatively small extent along its lengthwise extent in the direction of 
its travel whereby the frictional forces between the substrate S and the 
nozzles 26 and drums 28 are limited and the frictional resistance to its 
travel is reduced. Similarly, the function of the nip rolls 16 of the 
transport device 14 is merely to impart movement of the treated substrate 
S to the next station in the treating range and the transport device 
accordingly is not arranged to exert any pulling action on the substrate 
S. Furthermore, inasmuch as the substrate S has been treated prior to 
reaching the transport device 14, there is less danger of tearing of the 
substrate S in any event. 
As will be appreciated by those skilled in the art, the quantity of the 
foamed treating liquor applied to the substrate S per unit area thereof 
may be selectively controlled by varying in conventional manner the 
quantity of the treating chemicals fed into the foam generating apparatus 
while cooperatively varying the rotational speed of the drums 28. 
Similarly, the depth to which the foamed liquor penetrates the substrate S 
may be effectively varied by controlling the relative volume of the air 
component of the foam thereby to control the foam pressure. In the 
illustrated and above-described embodiment of the present foamed liquor 
applying apparatus, two such apparatus are serially-arranged for 
successively treating respectively the opposite sides of the substrate S. 
Thus, the respective foamed liquor applying apparatus incorporated in each 
machine 10,12 effects a decreasing penetration of the foaming liquor 
through the substrate S by each such apparatus with a resulting combined 
uniform penetration of the foam into the substrate. Advantageously, this 
arrangement of the two machines 10,12 also permits the application of 
different treating liquors to the opposite sides of the substrate S, if 
desired. It is to be understood, however, that the single foamed liquor 
applying apparatus of either machine 10 or 12 alone may be equally 
effective to apply a suitable foamed liquor through substantially the 
entire depth of the substrate S by the above-noted control parameters. The 
employment of two successive apparatus instead of one apparatus is 
considered to be ordinarily preferred in order to best obtain uniform foam 
penetration through the substrate and further to reduce any likelihood 
that excess foam may penetrate the substate S and enter the drums 28. 
It will thus be understood that the present foam applying apparatus 
effectively applies foamed treating liquor to the traveling substrate S by 
an extremely clean, economical operation in which virtually all foamed 
liquor emitted from the applicator nozzles 26 is applied to the substrate 
S and the present apparatus will be seen accordingly to be especially and 
advantageously adapted for use in treating fibrous textile substrates of 
non-woven, non-knitted character the structural integrity of which relies 
substantially on the cohesive forces between the fibers of the substrate. 
Substrates of this type present unique treating problems in that careful 
handling of traveling substrates of this type is necessary to prevent 
tearing or other damage thereto and, for this reason, treating apparatus 
conventionally employed with traveling woven, knitted or other substrates 
the fibers or yarns of which are mechanically integrated is unsuitable. 
The special non-woven substrate treating apparatus of the type described 
above have accordingly evolved along with the attendant problems. The 
present apparatus eliminates the problems heretofore so associated with 
the conventional treatment of traveling non-woven substrates by providing 
a means by which non-woven substrates may be firmly but limitedly engaged 
by a foam liquor applicator in a manner applying the foamed liquor 
directly to the substrate only while also transporting the substrate in 
its intended traveling path without exerting any significant potentially 
damaging force on the substrate. Application of the treating foam to any 
operative parts of the apparatus, and the resultant need for cleaning 
thereof, are eliminated. 
Of course, it is to be understood that the present apparatus is of broad 
applicability to and utility for the application of any type of foamed 
treating liquor to virtually any type of air permeable traveling substrate 
and it is, accordingly, contemplated that the present apparatus may be 
equally well employed for the foamed treatment of conventional knitted and 
woven fabrics. 
The present invention has been described in detail above for purposes of 
illustration only and is not intended to be limited by this description or 
otherwise to exclude any variation or equivalent arrangement that would be 
apparent from, or reasonably suggested by the foregoing disclosure to the 
skill of the art.