Note: Descriptions are shown in the official language in which they were submitted.
1094(~Z5
This is a divisional of Application 301,834 filed
;~pril 24, 1978.
This invention relates to apparatus for dispensing
plural component materials, and particularly to apparatus
for mixing and dispensing foams used for packaging and the
like.
Polyurethane foam systems of the thermosetting type
are typically products of a chemical reaction between a poly-
ol resin base and an isocyanate hardener (Frequently toluene
diisocyanate or methane diisocyanate). Each component of
the plural component material is by itself generally stable,
such that it will remain highly fluid for a considerable
length of time, provided it is properly stored. Mixing of
the resin and hardener components in the proper proportions,
however, initiates a chemical reaction that causes the com-
ponents to begin to polymerize and generate heat which vol-
atilizes a blowing agent ~generally included in one or both
of the components). Volatilization of the blowing agent
causes the resin to foam. The resin-containing component
includes, in addition to the polyol base and the blowing
agent ~which is frequently Freon 11 or Freon 12), a catalyst,
which controls the setting time of the foam, and a surfactant,
which controls the size of the foam cells.
A plural component dispensing device of the general
t~pe to which the ins~ant invention relates is disclosed in
Probst et al, United States Patent 3,799,403, issued March 26,
1974. ~he device of the instant invention constitutes an
improvement over the devices of the Pro~st et a~ patent, in
that the device presented herein is considerably simpler in
its construction and operation than devices of the Probst et
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1~)940ZS
.
`~ al type. Further, the device of the instant invention
allows additional flexibility in its use. For example,
the operator of the device of the instant invention can
mix with the components being dispensed a preselected
amount of air to achieve a desired spray pattern or amount
of atomization. It is further known to bring two components
together by directing streams of these components toward
each other into a chamber where the components are mixed ~y
~irtue of their own turbulence. See, for example, Hagfors,
United States Patent 3,437,273, issued April 8, 1969 and
~rueger, United States Patent 3,708,123, issued January 2,
1973. It is further known to provide a piston-and-cylinder
arran~ement, in which the piston reciprocates in a first
direction in response to fluid pressure on one side thereof
to drive a mixing and spraying system in a first direction
to dispense mixed components, and in a second direction in
response to fluid pressure on the other side thereof to
close such a mixing and spraying system to terminate dis-
pensing of mixed components. See, for example, Walter,
United States Patent 3,291,396, issued December 13, 1966.
Reference is here also made to the service manuals
for Decker Series RD25, RD45 and RD75 foam processing
systems, and particularly to the exploded view of the #2
head subassembly lS597-00 for such systems. These items
are available from Decker Industries, Inc., P. O. Drawer R,
5051 South East Federal Highway, Port Salerno, Florida 33492.
It is an object of the present invention to provide
a simple apparatus which is an improvement over devices of
40Z5
the type described in the aforementioned United States
Patents.
According to the invention, there is provided
a plural component dispensing apparatus comprising
means for providing flows of first and second components,
first and second valves for controlling flow of the first
and second components, respectively, and means for controlling
the first and second valves, the control means including
a trigger, means for operatively connecting the trigger
to the first and second valves so that actuation of the
trigger moves the first and second valves to positions
allowing flow of the first and second components, means for
mixing the first and second components, said mixing means
including a mixing chamber, first and second orifices from
which the first and second components are ejected into the
chamber in first and second streams which impinge against
one another at an angle as the streams exit from the first
and second orifices to mix the first and second components,
third means for supplying a third material, a third
2~ orifice adjacent the first and second orifices in the
mixing chamber, means in the housing for supplying the third
medium to the third orifice, a third valve for controlling
flow of the third medium from the third orifice, and means
for controlling the third valve independently of the
orientations of the first and second valves, and a nozzle
for providing a stream of the mixed first and second com-
ponents from their point of impingement out of the cham~er.
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1~19`4~25
In a further aspect the invention provides
a dispensing apparatus for plural component
materials adapted to be hand-held, comprising a housing
adapted to be connected with means for supplying flows of
first and second components and an operating fluid and to be
manipulated by hand, first and second valves carried by said
housing to control the flow of said first and secona components,
respectively, a fluid-operated piston carried within a cylinder
formed by said housing, first means operated ~y said piston
and effecting operation of said first and second valves as
said piston is moved between first and second positions by
the pressure of said operating fluid, second means providing
a mixing chamber within said housing to mix the first and
second components when flowin~ means to direct the mixed
components from the housing, a first trigger for controlling
the movement of said piston, the first trigger being carried
by the housing for operation by hand, said first trigger
directing a flow of operating fluid to move the piston to
said first position where said first means opens the valves
to permit the first and second materials to flow through
said val~es, into said mixing chamber for mixing and directed
expulsion through said directing means, and said second
position where said first means closes the valves, means for
providing a flow of a third material to the mixing chamber,
a third valve for controlling the third material flow, and a
second trigger controlling the third valve independently of
the position of the first trigger to permit mixing of the
third material in selected, desired amounts wit~ the first
and second components in the mixing chamber.
The invention may best be understood by referring
1~94025
to the following description and accompanying drawings which
illustrate the invention. In the drawings:
FIG. 1 is a highly diagrammatic view showing a
possible use of the apparatus of the instant invention;
FIG. 2 is a fragmentary sectional side elevational
view of a plural component mixing apparatus constructed
according to the present invention;
FIG. 3 is a sectional view of the apparatus of
FIG. 2 taken generally along section lines 3-3 thereof; and,
FIG. 4 is a partly sectional exploded perspective
view of a detail of the apparatus of FIGS. 1-3.
The plural component dispensing apparatus 10 of
the drawings is, as best illustrated in FIG. 1, a hand-held
device including a pistol grip 12 housing a trigger 14, and
a frame portion 16 to which the pistol grip 12 is attached.
Frame portion 16 includes an inlet 18 for air, an inlet 20
for a component A (for example, the resin component), and an
inlet 22 for component 8 (for example, the hardener). The
frame 16 desirably is constructed from cast aluminum or some
other material which is not affected by either of the com-
ponents, and which is capable of supporting moving inte~nal
components with relatively little wear. The components A
and B are dispensed from tanks 24, 25, respectively, through
a pump 28 which, i~ the illustrated embodiment, includes a
hydraulic cylinder 30 driving separate A and B component
sections thro~gh a yoke 32. Separate hoses 33, 3S deliver
the A and B components, respectively, to the apparatus 10.
Referrinq now to FIGS. 2-3, air from inlet 18 is
1~)94025
supplied through a manifold 34 to a forward-extending air
passageway 36 and a downward-extending air passageway 38.
An air passageway 40 extends upward from a generally cylin-
drically shaped trigger mechanism housing 44. As best illus-
trated in FIG. 3, passageway 40 does not intersect passage-
way 36. Upward-extending air passageway 40 extends through
the wall of a cylinder 46 near the forward end 48 of cylinder
46. The rearward end 50 of cylinder 46 is defined by an end
52 of a large metal plug 54. An air passageway 56 extends
upwardly from housing 44 and intersects cylinder 46 near
the rearward end 50 thereof.
A piston 47 is reciprocably received in cylinder
46. Piston 47 includes a ring 49 which seals the piston to
the wall of cylinder 46 and defines within cylinder 46 a for-
ward chamber 53 and a rearward chamber 55.
Housing 44 houses a plunger-type trigger mechanism
58 which has enlarged annular forward and rearward portions
60, 62. Portions 60, 62 are grooved, and annular seals 64,
66 are mounted in the grooves in portions 60, 62, respec-
tively. Nechanism 58 includes a rearwardly-opening cylindri-
cal chamber 68 in which is located a coil sprir.g 70. Spring
70 is positioned against the inside rear end 72 of housing
44 to urge mechanism 58 forward. with mechanism 58 in the
forward position, a chamber 76 defined between the wall of
housing 44 and mechanism 58, and between the forward and
rearward portions 60, 62 connects passageway 38 to passage-
way 40, ~nd thus to cylinder 46 in front of piston 47.
When trigger 14 is depressed, mechanism 58 is
i~940Z5
mo~ed` toward the rear end 72 of housing 44, and chamber 76
connects passageway 38.to passageway 56. Piston 47 is there-
by forced toward the forward end 48 of cylinder 46. Air
trapped in the forward chamber 53 of cylinder 46 is allowed
to exhaust through passageway 40, housing 44, and an air
passageway 78 formed in grip 12 in the forward lower side
of housing 44.
: When trigger 14 is released, mechanism 58 is re-
turned by spring 70 to its forward position illustrated in
FIG. 2, in which air from manifold 34 passes through air
passageway 38, chamber 76 and passageway 40 to the forward
end 48 of cylinder 46. Piston 47 is thereby forced to the
rearward end 50 of cylinder 46 as air in rearward chamber 55
is exhausted through passageway 56 and the upper rearward
portion of housing 44 and a passageway 80 provided in the
bottom of the rearward end of housing 44.
As will be appreciated, actuation of trigger 14
thereby causes reciprocation of piston 47 in cylinder 46.
: A rod 82 extends through an axial bore 84 in piston
47. Piston 47 is positioned on the end of rod 82 ~y a pair
of split locking rings 86 which are situated in annul ar
grooves pro~ided on connecting rod 82. ~od 82 extends for-
ward from piston 47 through a seal 88 and a longitudinally
extending bore 90 pro~ided in frame 16. Rod 82 is recipro-
cable in bore 90. The forward end of rod 82 is formed to
provide a rack 92.
R~ferring now particularly to FIGS. 2 and 4, the
structure of the forward end of frame 16 will be described
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1~)940~5
in detail. The forward end of the frame includes a valve
housing section 94, a valve retaining plate 96, an orifice
plate 98 and an end plate 100. These portions are all
attached to the for~ard end of frame 16 by a plurality of
cap screws 102 (only one of which is illustrated in FIG. 4)
which extend through each of portions 94-100 and connect
these portions to the forward end of frame 16. This parti-
cular construction provides for rapid and easy disassembly
of portions 94, 96, g8 and 100 from frame 16 when dispensing
operations are not being conducted. This feature simplifies
cleaning of these portions, since they can be placed in a
tank of some suitable solvent when not in use and soaked.
This feature also permits one or more of these portions to
be replaced or "rotated" with duplicate portions in the
event they become obstructed by a hardened mixture of com-
ponents A and B.
Frame 16 further includes two fittings 104, 106
on top of the frame for connection of hoses 33, 35, respec-
tively, (FIG. 1) thereto. Passageways 108, 110 extend
downwardly and forwardly from fittings 104, 106, respectively,
into frame 16. Passageways 108, 110 terminate in orifices
112, 114, respectively, tFIGS. 2 and 4). These orifices are
surrounded by annular seals 116. Attachment of valve hous-
ing portion 94 to the end of frame 16 compresses seals 116.
Housing portion 94 includes a pair of enlarged cylindrical
openings 118, 120 which are axially aligned with orifices
112, 114, respectively. Each of openings 118, 120 houses a
ball valve 122, 124, respectively, between a pair of facing,
1~)94025
cup-shaped inserts 126. Axially extending passageways 128
are provided in all of the inserts 126, the passageways 128
being axially aligned with orifices 112, 114. Passageways
130, 132 extend diametrically through ball val~es 122, 124,
respectively. Passageways 130, 132 align with their respec-
tive passageways 128 in inserts 126 when valves 122, 124
assume a first orientation (illustrated in FIG. 4). Other
orientations of valves 122, 124 move passageways 130, 132
out of alignment with passageways 128.
The sperically-shaped valves 122, 124 are provided
with slots 134, 136 respectively. Slots 134, 136 open up-
wardly through openings 138, 140, respectively, in valve
housing portion 94. Axially upwardly from openings 138,
140, cavities 142, 144 are provided in portion 94. Cavities
142, 144 both intersect longitudinal bore 90 along their
adjacent sides. Cavities 142, 144 are sized to receive
pinion gears 146, 148, respectively, with the teeth of these
pinion gears meshing with rack 92 on connecting rod 82.
Shafts 150 on pinion gears 146, 148 are provided with O-ring
seals 152 to seal the shafts 150 and openings 138, 140.
Shafts 150 are also provided with axially extending tongues
154 which are designed to fit into slots 134l 136. Rotation
of pinion gears 146, 148 which results from reciprocation of
connecting rod 82 turns ball valves 122, 124, respectively,
to open passageways 130, 132 for material flow from aper-
tures 112, 114 through openings 156, 158 in spacer plate 96.
An additional opening 160 in housing portion 94 is
aligned with an opening 162 in valve retaining plate 96.
9 _
~40Z5
These openings are aligned with air passageway 36 in frame
16 to supply air to the forward end of dispenser 10.
Orifice plate 98 includes passageways 164, 166, 168
which extend from openings 156, 158, 162, respectively, in
valve retaining plate 96 forward and toward one another,
terminating at orifices 170, 172, 174, respectively. Mate-
rials discharged from orifices 170, 172, 174 Lmpinge against
one an~ther, resulting in considesable turbulence and mixing
of these materials as they leave orifices 170, 172, 174.
In the illustrated embodiment, the impingement angle between
the streams of components A and B is between 100 and 108
and the orifice diameters are .060 inch. Desirably, for more
viscous components A and B the orifice diameters will be made
larger and the angle at which the component streams impinge
against each other will also be larger. For less viscous
components, the impingement angle and orifice diameters will
be smaller.
End plate 100 includes a portion defining a mixing
chamber 176 in which this impingement among the various
2a materials dispensed through orifices 170, 172, 174 occurs.
An annular seal 178 surrounds chamber 176 to seal it against
leakage when end plate 100 and orifice plate 98 are bolted
together~ End plate 100 further includes a nozzle 180
which provides for a flow of mixture from mixing chamber 176
,from apparatus 10. Housing portion 94 includes a gear cover
181 (FIG. 2) which bclts to the top of the housing to retain
pinion geaxs 146, 148.'
Actuation of trigger 14 pro~ides a path between
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1~94025
fittings 104, 106 and orifices 170, 172, for components A
and B of the foam packaging material. A control 182, separate
from tsigger 14, is provided to supply air from passageway
36 to orifice 174. Separate control 182 is provided for the
air system, since it may be desirable to use air as a purging
mediu~ for removing the two-component mixture from mixing
chamber 176 after trigger 14 is released.
To this end, and with particular reference to FIG.
3, control 182 includes a trigger 184 having a shaft 186, a
shoulder 188, and a valve 190. Shoulder 188 and valve 190
are slidably received in a bore 192 which extends generally
transversely of frame 16 and intersects passageway 36 inter-
mediate its end. Val~e 190 includes a recessed rearward
portion l9i which houses a coil spring 196. Spring 196
rests against the end 200 of bore 192. Spring 196 urges
valve 190 into a position to prevent air flow through
passageway 36. A threaded bore 202, which is substantially
larger in diameter than stem 186 is coaxial with bore 192.
A threaded adjustment nut 204 includes a bore 206 which
reciprocably receives stem 186 and captures stem 186 between
shoulder 188 and the operating button 208 on the end of stem
186. Button 208 can be pressed to provide a flow of air
past the reduced diameter portion of stem 186 between shoulder
188 and valve 190. Further, continuous air flow through
passageway 36 can be established by turning threaded adjust-
ment nut 204 against shoulder 188 to place reducad diameter
portion 210 in passageway 36. In this manner, continuous
air flow can be achieved to mix air with components A and B
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as they are mixed, or to provide a continuous or intermittent
air purge of mixing chamber 176 when components A and B are
not being mixed.
Referring again to FIG. 1, in a typical application,
apparatus 10 will be hand-held by an operator who will ais-
pense some of the mixed components A and B into a container
220. Typically, container 220 will be a cardboard box.
After a layer 222 of the mixture has been dispensed, and
while this layer is still in a semi-liquid state, a layer
224 of flexible film is placed on top of layer 222 and an
article 226 to be packaged is pressed onto layer 224, forming
an indentation in layer 222. Another layer 228 of flexible
film is then placed on top of article 226, and the operator
of apparatus 10 dispenses an additional amount of mixed
components A and B onto layer 228. The depth of this las~
layer 230 is sufficient so that when layer 230 cures, con-
tainer 220 is substantially filled. Article 226 is thereby
well protected for shipping.
2~
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