Stereo dispensing container and system

A low cost stereo dispensing container (e.g. a disposable caulking cartridge) from which two part fluid products may be simultaneously dispensed in predetermined proportions relative to one another. A first material (e.g. a catalyst) is stored within a flexible blister. The blister may be adhesively affixed to a side of the container. In the alternative, the blister may be extruded or injection molded along a side of the container during manufacture. The second material (e.g. a resin) is stored within a holding chamber formed in the container alongside the blister. A plunger is moved through the container to ride over and compress the blister and thereby cause the first material to be expulsed therefrom into a spout of the container. At the same time, the volume of the holding chamber is reduced to thereby cause the second material to be simultaneously expulsed therefrom into the spout.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a relatively low cost, stereo dispensing 
container (e.g. a disposable caulking cartridge) and to an efficient 
system by which two different materials may be simultaneously expulsed 
from a single container in predetermined proportions relative to one 
another. 
2. Background Art 
It is frequently necessary to mix together different ingredients according 
to a particular ratio in order to form a composite material which depends 
upon a precise introduction of one ingredient to the other. For example, a 
catalyst and a resin are mixed together to form a fast hardening epoxy. A 
proper ratio of catalyst to resin is required to speed the curing and form 
a hard, durable epoxy. The catalyst and resin are presently carried in 
separate containers or tubes. The user must carefully dispense the 
catalyst and resin from their respective containers while making sure that 
the correct amounts of each will be mixed together. This is often a slow 
and cumbersome process and frequently results in both wasteful mistakes 
and inefficiency due to the duplication of activities (i.e. two containers 
are opened, two plungers are pushed or two tubes are squeezed, two fluid 
supplies are progressively mixed together, etc.). 
To overcome some of the aforementioned inefficiencies, stereo dispensers 
have been used by which to simultaneously dispense two different materials 
from separate storage compartments. These dispensers resemble a syringe, 
but include a pair of piston assemblies that are interconnected for 
simultaneous movement through the respective storage compartments in which 
the materials to be dispensed are stored. While the piston assemblies are 
advantageously moved together, there is no inexpensive or easy way to 
change the ratio of the materials dispensed as a result of such movement. 
Moreover, the conventional stereo dispensers are relatively complex in 
construction, thereby using a greater number of component parts which 
results in a correspondingly increased cost of manufacture. 
Examples of known dispensers, including those described above, are 
available by referring to one or more of the following U.S. Pat. Nos.: 
3,013,697 issued Dec. 19, 1961 to Wilber Gill; 
3,330,444 issued Jul. 11, 1967 to Kenneth Raypholtz; 
4,014,463 issued Mar. 29, 1977 to Paul Hermann; 
4,069,091 issued Jan. 17, 1978 to Dick van Manen; 
4,205,766 issued Jun. 3, 1980 to Douglas White; and 
5,203,839 issued Apr. 20, 1993 to Kenneth Skaggs. 
SUMMARY OF THE INVENTION 
A low cost stereo dispensing container is disclosed which uses an efficient 
system for simultaneously dispensing particular amounts of two different 
fluid materials stored therein according to any predetermined ratio. In 
the preferred embodiment, the dispensing container is a disposable 
caulking cartridge of the type commonly found in the construction and home 
improvement industries. A flexible blister extends longitudinally along an 
interior side of the cylinder of the caulking cartridge. The blister may 
be either adhesively affixed to the side of an existing caulking 
cartridge, or the blister may otherwise be extruded or injection molded 
along the side during manufacture. The blister is filled with a first 
material (e.g. a catalyst) and sealed at the opposite ends thereof. The 
remainder of the caulking tube forms a holding chamber for a base material 
(e.g. a resin) to be mixed with the contents of the blister in 
predetermined proportions relative to one another. The holding chamber 
communicates with the usual spout of the caulking cartridge through a 
passageway formed in the distal end wall of the cartridge. 
An exit channel extends through the forward end of the blister. The exit 
channel terminates at a catalyst outlet tube which projects longitudinally 
from the cartridge to be surrounded by and coaxially aligned with the 
spout. Both the outlet tube and the spout are initially closed to prevent 
the leakage of catalyst and base material from their respective storage 
locations at the blister and holding chamber within the cartridge. 
In stereo displacement operation, the tip of the spout and the leading end 
of the outlet tube are severed. A plunger that is initially at rest at the 
proximal end of the caulking cartridge is then driven distally through the 
interior of the cartridge towards the spout by means of a conventional 
caulking gun, or the like. The distal movement of the plunger through the 
caulking tube causes a corresponding amount of base material in the 
holding chamber to be expulsed by way of the spout. At the same time, the 
plunger rides over a portion of the blister to compress the blister and 
thereby cause a measured supply of catalyst to be simultaneously expulsed 
via the exit channel and outlet tube. The amount of catalyst expulsed is 
dependent upon the total volume of the blister and the distal displacement 
of the plunger through the interior of the cartridge. The amount of 
catalyst to be mixed with a known amount of the base material can be 
selectively changed by choosing the cross-sectional dimensions of the 
blister to provide a particular ratio of catalyst to base material. 
Accordingly, the catalyst and base material can be expulsed together so as 
to achieve a composite material having predetermined proportions of one 
material to the other. 
According to an additional embodiment of the present invention, a threaded 
plug is carried by the plunger. The plug can be removed from the plunger 
to create an opening through which base material may be added to the 
holding chamber of the caulking cartridge. According to another 
embodiment, the spout of the caulking tube may be interfaced with a spray 
tip by which to permit the catalyst and base material to be expulsed in a 
particular ratio and sprayed onto a surface by means of air under pressure 
.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
The stereo dispensing container and system which form the present invention 
is now described while referring to the drawings. Referring initially to 
FIG. 1, the dispensing container is, in the preferred embodiment, a 
conventional, low cost, commercially available caulking cartridge 1. That 
is, caulking cartridge 1 has a cylindrical body that is typically made 
from plastic, metal or cardboard and commonly used in the building and 
home improvement industries to dispense caulk, adhesive, and the like. The 
caulking cartridge 1 has the usual spout 2 projecting from the distal end 
wall 10 thereof and a plunger 20 initially at rest across the proximal 
end. 
Caulking cartridges have heretofore been filled with a single material to 
be uniformly dispensed through the spout. In accordance with one aspect of 
the present invention, a standard, disposable caulking cartridge 1, as 
described above, is filled with two different materials that can be 
dispensed at the same time in predetermined proportions relative to one 
another. More particularly, a flexible blister 4 to be manufactured from a 
metal foil or tough plastic, runs longitudinally through the interior of 
the caulking cartridge 1 between the proximal and distal ends thereof. 
That is, and referring concurrently to FIGS. 1, 2a, 2b, 2c of the drawings, 
the blister 4 is formed from a long, thin bottom layer 6 which is to be 
adhesively bonded to the interior of the existing caulking cartridge 1 so 
as to extend from the distal end of the cartridge, along a side of the 
cylindrical body thereof, and project beyond the proximal end (best shown 
in FIG. 2b). The projection 7 of the bottom layer 6 adjacent the blister 4 
is bent around the proximal end of the cartridge 1 so as to terminate at 
and be secured to an exterior side of the body in order to provide a 
surface upon which to list the contents of the blister 4 (best shown in 
FIG. 2c). The blister 4 also includes a top layer 8 which is heat or 
otherwise sealed to the bottom layer 6 to form an envelope. The top layer 
8 of blister 4 rises upwardly from the bottom layer 6 and assumes a 
generally arcuate shape (best shown in FIG. 4) so that the contents (e.g. 
a catalyst 12) of the blister 4 can be stored in the space within the 
envelope between the bottom and top layers 6 and 8. The outside surface of 
top layer 8 is preferably coated with a lubricant (e.g. a wax) to 
facilitate the movement and smooth the travel of a plunger 20 through the 
caulking cartridge 1 and over the blister 4 for a purpose that will soon 
be described. 
FIGS. 2a, 2b and 2c illustrate the steps by which a blister 4 is attached 
to the interior of the conventional monaural caulking cartridge 1 of FIG. 
1 to form a stereo dispensing container without having to make any 
manufacturing changes to the cartridge. A series of blisters (one of which 
being shown in FIG. 2a) may be manufactured end-to-end one another (e.g. 
in a daisy chain) to facilitate the installation of a plurality of such 
blister within a respective plurality of caulking cartridges. Each blister 
4, such as that shown in FIG. 2a, is detached from the series of other 
blisters so as to be inserted in a cartridge 1 and moved towards the 
distal end from which the spout 2 extends. Each blister 4 of the series of 
blisters includes the envelope defined by the bottom and top layer 6 and 8 
between which the catalyst (e.g. designated 12 in FIG. 4) is stored, the 
aforementioned projection 7 extending longitudinally from and adjacent one 
end of the envelope, and a distal end wall 10 extending longitudinally 
from and adjacent the opposite of the blister envelope. One end of a 
catalyst outlet tube 14 extends through the distal end wall 10 and 
communicates with the interior of the blister 4 through the otherwise 
sealed forward end thereof. The opposite end of outlet 14 projects 
outwardly through a central passageway 18 formed in the distal end wall 10 
and turns at a right angle to the longitudinal plane of end wall 10, 
blister 4 and projection 7. 
During installation, the distal end wall 10 adjacent blister 4 is rotated 
in the direction of the reference arrow 16 of FIG. 2a until the end of the 
outlet tube 14 extending from distal end wall 10 is axially aligned with 
the longitudinal axis of the caulking cartridge 1. As shown in FIG. 2b, 
the blister 4 is then pushed through the cartridge 1 towards the spout 2 
until the rotated distal end wall 10 adjacent blister 4 is flush with the 
distal end of the cartridge 1 and the catalyst outlet tube 14 is 
surrounded by and coaxially aligned with the spout 2. As previously 
disclosed, the bottom layer 6 of blister 4 is provided with an adhesive by 
which to enable the blister to be affixed to a side of the cylindrical 
body of the cartridge. Moreover, the distal end wall 10 may also be 
covered with an adhesive by which to enable wall 10 to be affixed to the 
distal end of the cartridge. Lastly, and as is best shown in FIG. 2c, the 
projection 7 adjacent the blister 4 is bent around the proximal end of the 
cartridge 1 to provide a surface upon which to identify the material 
stored within the blister. 
The remaining interior volume of the caulking cartridge 1, other than the 
volume consumed by the blister 4, forms a holding chamber 19 for a base 
material (e.g. a resin) to be mixed in predetermined proportions with the 
catalyst (12 in FIG. 4) stored in blister 4. The holding chamber 19 
communicates directly with the spout 2 of cartridge 1 by way of the 
aforementioned central passageway 18 through the distal end wall 10. Thus, 
the catalyst 12 stored in blister 4 is available from the catalyst outlet 
tube 14, while the base material stored in holding chamber 19 is available 
from the spout 2 via passageway 18. However, it will be appreciated that 
the blister 4 isolates the different materials stored in the cartridge 1 
until they are expulsed therefrom to form a composite material. 
In accordance with a second aspect of the present invention, and referring 
now to FIG. 3 of the drawings, a caulking cartridge 22 can be constructed 
during manufacture so as to eliminate the step of adhesively affixing the 
blister 4 to the interior of the convention caulking cartridge 1 of FIG. 
1. That is, instead of forming blister 4 from bottom and top layers 6 and 
8 that are sealed one atop the other, a blister wall 24 can be extruded or 
injection molded longitudinally along a side of the caulking cartridge 22 
during manufacture of the cartridge. In this regard, both the cylindrical 
body of caulking cartridge 22 and the blister wall 24 would be formed from 
the same material (e.g. a flexible plastic). Like the top layer 8 of the 
blister 4 of caulking cartridge 1, the blister wall 24 of caulking 
cartridge 22 has an arcuate shape and is spaced radially inward from the 
cartridge 22 so that a catalyst 25, or the like, may be stored in the 
space between catalyst wall 24 and the adjacent side wall of the 
cylindrical body (best shown in FIG. 5). 
As is best shown in FIG. 6 of the drawings, an exit channel 26 communicates 
with the forward end of the blister formed by blister wall 24 and then 
extends radially through the distal end wall 27 of the caulking cartridge 
22. The forward end of the blister is otherwise sealed against the distal 
end wall 27 to prevent the inadvertent escape of catalyst. One end of a 
catalyst outlet tube 28 is bonded to the exit channel 26 at distal end 
wall 27. The opposite end of the catalyst outlet tube 28 extends 
longitudinally from the exit channel 26 to be surrounded by and coaxially 
aligned with the spout 48 of caulking cartridge 22. 
The remainder of the manufactured caulking cartridge 22, other than that 
consumed by the blister defined by blister wall 24, forms a holding 
chamber 30 for storing a base material 32 (e.g. a resin) which is 
ultimately to be mixed with the catalyst 25 stored in the blister in 
predetermined proportions relative to one another. The holding chamber 30 
communicates directly with the spout 48 of the cartridge 22 by way of a 
central passageway 34 formed through the distal end wall 27 of caulking 
cartridge 22 (best shown in FIG. 7). Thus, the catalyst 25 stored in the 
blister defined by blister wall 24 of caulking cartridge 22 is available 
from the catalyst outlet tube 28 via exit channel 26, while the resin 32 
stored in the holding chamber 30 of cartridge 22 is available at the spout 
48 via passageway 34. 
FIGS. 8, 9 and 10 of the drawings illustrate the steps of the joining the 
spout 48 to the distal end wall 27 to form the caulking cartridge 22 with 
the catalyst outlet tube 28 and the spout 48 maintained in coaxial 
alignment with one another and the blister defined by wall 24 
communicating with the exit channel 26. More particularly, projecting from 
the disk-like base 36 of the spout 48 is at least one post 38. An 
oppositely aligned slot 42 is formed through the distal end wall 27 and 
sized to receive the post 38 therewithin. One end of the catalyst outlet 
tube 28 is affixed to the exit channel 26, such that tube 28 projects 
longitudinally and outwardly from the distal end wall 27. The spout 48 and 
end wall 27 are permanently mated together with outlet tube 28 surrounded 
by the spout (best shown in FIG. 9) when the end of the post 38 is 
received in the slot 42 and melted to form a button head 46. The button 
head 46 prevents the inadvertent separation of the spout 48 from the 
distal end wall 27. 
The assembled combination of spout 48 and distal end wall 27 is secured to 
the distal end of the caulking cartridge 22 by means of spin welding, or 
the like. The holding chamber 30 in which the base material (e.g. resin) 
is stored is aligned with the passageway 34 to permit communication 
between holding chamber 30 and spout 48. The forward end of the blister 
wall 24 is heat or otherwise sealed to the distal wall 27 at a joint 45 to 
close the blister against the distal wall 27 except for exit channel 26 
which allows communication between the blister defined by blister wall 24 
and the catalyst outlet tube 28. Lastly, a plunger 50 is located within 
the proximal end of the caulking cartridge 22 and adapted to move in a 
direction towards the distal end wall 27. To this end, the blister wall 24 
may be coated with a lubricant (e.g. a wax) to facilitate the movement and 
smooth the travel of the plunger 50 through the caulking cartridge 22 and 
over the blister defined by wall 24 for a purpose that will now be 
described. 
The operation of the stereo dispensing container (i.e. caulking cartridge 
1) of the present invention is now described in detail while referring to 
FIGS. 11, 12 and 13 of the drawings. FIG. 11 shows the caulking cartridge 
1 after the blister 4 has been adhesively affixed thereto in the manner 
described while previously referring to FIGS. 2a, 2b and 2c. That is to 
say, the longitudinally extending blister 4 has been pre-filled with a 
supply of catalyst 12, or other suitable material, and the holding chamber 
19 is loaded with base material 54, such as a resin, or the like. The 
plunger 20 is initially in the at rest condition at the proximal end of 
cartridge 1 adjacent the sealed rear end of the blister 4. 
In FIG. 12, the tips of the formerly closed spout 2 and catalyst outlet 
tube 14 of caulking cartridge 1 are severed to permit the flow of material 
outwardly from each. Next, the plunger 20 is moved through cartridge 1 
towards the distal end wall 10 thereof. The foregoing may be accomplished 
by locating the cartridge 1 within and operating a conventional caulking 
gun (not shown). As the plunger 20 moves distally through the cartridge 1, 
the volume of the holding chamber 19 established between plunger 20 and 
end wall 10 and running alongside blister 4, is reduced. Accordingly, the 
base material 54 stored in holding chamber 19 is expulsed therefrom by way 
of the spout 2 and the central passageway 18 (of FIG. 2c) which extends 
through distal end wall 10 for communication with chamber 19. During its 
distal travel through the caulking cartridge 1, the plunger 20 will also 
ride over the blister 4 in which a supply of catalyst 12 has been stored. 
As a result of the foregoing, the arcuate blister 4 will be progressively 
compressed or flattened against the cylindrical body of cartridge 1 (best 
shown in FIG. 13 and designated by reference 4-1). Accordingly, the 
catalyst 12 will be expulsed from the blister 4 by way of the catalyst 
outlet tube 14 which communicates with the forward end of the blister 
(best shown in FIG. 2a). 
The more plunger 20 moves through caulking cartridge 1, the greater will be 
the reduction in volume of the holding chamber 19 and the compression of 
blister 4. Thus, more catalyst 12 and base material 54 will be expulsed 
from the blister 4 and holding chamber 19, respectively. However, and as 
should now be apparent, the catalyst 12 and base material 54 are dispensed 
from caulking cartridge 1 in constant proportions relative to one another, 
regardless of the displacement of plunger 20. Therefore, the guess work 
that has heretofor been associated with expulsing catalyst and resin from 
conventional dispensing systems is advantageously eliminated. What is 
more, the amount of catalyst 12 to be expulsed from cartridge 1 for mixing 
with the base material 54 can be selectively changed by a manufacturer 
simply choosing the dimensions of the blister 4 so that a particular ratio 
of catalyst to base material will be accurately achieved to meet the 
requirements of the final composite material. Thus, the user is provided 
with a low cost, fully disposable stereo dispensing container which 
permits a plurality of ingredients needed to form the composite material 
(e.g. an epoxy resin) to be efficiently and reliably introduced to one 
another. 
FIGS. 11-13 illustrate the operation of the conventional caulking cartridge 
1 (of FIG. 1) within which a prefilled blister 4 has been adhesively 
affixed. However, it is to be expressly understood that the operation of 
the modified cartridge 22 (of FIG. 3) within which a catalyst wall 24 is 
extruded or injection molded during manufacture is identical to the 
operation of the existing cartridge 1 except that catalyst 25 is expulsed 
by way of the catalyst outlet 28 and exit channel 26 that extends through 
the distal end wall 27 of cartridge 22 so as to communicate with the 
forward end to the blister that is defined by blister wall 24 (best shown 
in FIG. 6). In addition, the blister wall 24 should be sufficiently thin 
so that when such wall is deflected (i.e. flattened) against the opposing 
side of the cartridge cylinder by the plunger 50 riding thereover, the 
wall 24 will become mechanically invisible to the plunger so as not to 
impede the continued distal movement thereof. 
FIGS. 14 and 15 of the drawings illustrate a first alternate embodiment of 
the present invention. More particularly, the plunger 20 at the proximal 
end of caulking cartridge 1 or the plunger 50 at the proximal end of 
caulking cartridge 22 (not shown) may include a removable, threaded plug 
52. The threaded plug 52 has a screw-threaded body 55 that is adapted to 
be removably received within a correspondingly screw-threaded hole 56 
formed through the plunger 20 (best shown in FIG. 15). With the plug 52 
removed from plunger 20, the user will be able to load the holding chamber 
19 of cartridge 1 with the base material (e.g. 54) and/or a colorant of 
his choice. In this regard, the threaded plug 52 has a suitably shaped 
head 58 to facilitate the removal of plug 52 from plunger 20 by means of 
an appropriate tool (not shown). 
FIG. 16 of the drawings illustrates a second alternate embodiment of the 
present invention. More particularly, a disposable spray tip 60 is 
positioned over the spout 2 of the caulking cartridge 1. Spray tip 60 
includes a hollow body 61 and an air stem 62 extending from body 61 to be 
attached to a source of air under pressure via suitable flexible tubing 
64. In operation, the catalyst and base materials that are expulsed from 
the blister and holding chamber 4 and 19 of the cartridge 1 are delivered 
to the body 61 of spray tip 60 by way of spout 2. Accordingly, a uniform 
mixture of air (supplied to body 61 via tubing 64 and air stem 62), 
catalyst and base material can be continuously sprayed through an exit 
orifice 66 formed through an end of the spray tip 60 so as to efficiently 
and accurately spray a distant surface (not shown). One such spray tip 60 
which is suitable for use with caulking cartridge 1 is that described in 
my previously issued U.S. Pat. No. 4,951,876 issued Aug. 28, 1990. 
It will be apparent that while a preferred embodiment of the invention has 
been shown and described, various modifications and changes may be made 
without departing from the true spirit and scope of the invention. For 
example, it is within the scope of this invention to include a plurality 
of blisters within the caulking cartridge. Each blister would store a 
different material and communicate with the spout to provide the 
ingredients for a multi-part composite from a single container.