[0001] The present invention relates to the field of containers for dispensing fluids under
pressure. More particularly, the invention relates to a plastic container for dispensing
fluids under pressure which is adapted to employ an expandable bag to generate the
expulsion pressure within the container, and the method for manufacturing such a container.
[0002] Containers for dispensing fluids under pressure have traditionally fit into two categories:
(1) pressurized containers, such as the common aerosol container, in which constant
pressure is exerted on the fluid to be expelled both during use and non-use; and (2)
pump-type containers in which the user creates the expulsion pressure during use by
manual actuation of a pump apparatus. Commercially suitable pump-type containers have
been constructed from a variety of materials, including metals, glass, ceramics and
plastics, among others. Since the expulsion pressure is only developed during times
of actual use in these containers, complete gas impermeability has not been a design
requirement.
[0003] In contrast, commercially available pressurized containers have almost exclusively
been constructed of metal. By and large, gas propellants within the container have
provided the requisite pressure for expelling the fluid contents of the container
upon actuation of a valve mechanism. Gas impermeability has therefor been a prime
requirement for such containers, and since techniques for forming gas impermeable
seals in metal containers have long been successful, metal containers have prevailed.
[0004] Metal dispensing containers do possess disadvantages, however, not the least of which
are high material costs and manufacturing complexity. Further, such metal containers
generally employ mounting cups in which the valve assembly is mounted and which must
be crimped to the top portion of the container. Consequently, efforts have been made
to produce pressurized dispensing containers made from other materials, especially
plastics. To date, however, these efforts have not resulted in an entirely satisfactory
alternative to the pressurized metal container.
[0005] For example, U.S. Patent No. 3,140,802 discloses a pressurized dispensing container
which includes a collapsible bag and a separate compartment into which an expandable
fluid, such as "Freon" is placed. The bag is seated securely in a container which
may be constructed of plastic, and attached to the side wall of the container by an
adhesive or by heat sealings. (Col. 3, lines 4-7). The lower surface of the bag is
adjacent to a "cradle" which forms one wall of the Freon-containing compartment. Holes
are formed in the cradle so that the expanding gas can exert pressure on the exterior
surface of the bag and cause its contents to be expelled when the valve of the container
is actuated. This arrangement represents an attempt to separate the fluid contents
to be expelled from the container from the pressure-producing gas propellant and thus
reduce the number of sealing locations where the gas can escape.
[0006] The seals between the bag and the interior wall of the container and the lower portion
of the container thus become critical in assuring that the gas propellant does not
escape into the atmosphere.
[0007] U.S. Patent Nos. 3,698,595 and 3,791,557 are representative of an alternative approach
to the solution of the gas permeability problems which have heretofore been endemic
to pressurized plastic dispensing containers. Both of these patents disclose pressurized
dispensing containers in which the pressure is developed on the fluid to be expelled
by the contraction of an elastic bladder in which the fluid is contained. The former
patent states that one of the advantages of a bladder-type container such as the one
disclosed therein is that the container assembly can be made of plastic. (Col. 1,
lines 34-38). Bladder-type containers thus solve the gas permeability problem by eliminating
gas as a propellant altogether. Quite obviously, the structural integrity and contrasting
characteristics of the bladder material are limiting factors on the suitablity of
this type of container for commercial use.
[0008] Lastly, British Patent Publication No. 2,101,225 discloses a plastic dispensing container
which, like the common metal aerosol container, uses a gas propellant mixed in with
the fluid to be expelled to create the requisite explusion pressure. In this case,
an attempt is made to solve the gas permeability problem by a variety of sealing arrangements
between the valve assembly portion of the container and the vessel portion. A metal
valve cup is used in the preferred embodiment and sealing is accomplished by crimping
the metal over the plastic rim or "bead" of the vessel portion of the container.
[0009] The present invention ia an improved plastic pressurized dispensing container in
which the need for the cumbersome bag and bladder arrangements and the relatively
complex and costly sealing arrangements shown in the prior art is eliminated. Moreover,
the present container is made entirely of plastic aside from the valve components
and possesses a minimal number of component parts, thus simplifying manufacture. The
reduced cost and simplicity of the container of the invention makes it much more suitable
for large-scale commercial use than both metal and plastic containers in the prior
art.
[0010] The plastic container of the invention includes two essential component parts, an
upper portion which house the valve mechanism necessary for dispensing of the fluid
product, and a lower portion which when sealed to the top means forms the chamber
in which the fluid to be dispensed is retained. The dispensing valve is housed in
the upper portion of the container in a receptable formed preferably by injection
molding, thus eliminating the need to seat the valve assembly within a mounting cup
and crimp the cup to the top of the container in manufacture.
[0011] Internal pressure for expelling the contents of the container upon actuation of the
valve is provided by an expandable bag located within the chamber in which the fluid
to be expelled is retained. The bag contains compositions which when reacted together
generate a gas, thereby inflating the bag and causing the bag to exert pressure upon
the contents to be expelled from the container. Such an expandable bag is disclosed
in U.S. Patent No. 4,376,500.
[0012] To prevent the expansion of the bag from blocking release of any portion of the fluid
contents within the chamber, a tube such as that disclosed in the aforementioned U.S.
Patent No. 4,376,500 may be included within the chamber to provide a clear passage
for expulsion of the last remaining fluid within the container as the bag reaches
its fully expanded condition. Alternatively, a rib may be integrally formed along
the portion of the container forming the side wall of the fluid-containing chamber
to accomplish the same purpose.
[0013] In a similar vein, a valve skirt or closure is provided within the top means of the
container around the periphery of the valve mechanism in order to prevent any portion
of the expanding bag from obstructing the escape of fluid through the valve. The valve,
which may be of a male or female type is mounted within a receptacle molded in the
top end of the upper portion of the container. The valve means is retained in place
by means of a spring member mounted within the closure and urging the valve against
the receptacle wall.
[0014] ln order to permit the most efficient utilization of space and simplify manufacture,
each of the structural components of the container are shaped such that they will
nest together in cup fashion. In the assembly process for the preferred embodiment,
a cup-like bottom means from a nested stack is fed onto the assembly line and conveyed
to a station where the fluid to be dispensed is poured into it and then conveyed to
a further station where the expandable bag is dropped into the open mouth of that
bottom means. The lower portion of the container into which the expandable bag is
inserted is formed with an unobstructed or generally full opening. In this manner,
the expandable bag may be inserted without any sideways crushing necessary to facilitate
insertion into conventional aerosol containers having narrow openings.
[0015] At the next two stations, the top means of the container is first seated onto the
open mouth of the bottom means and then welded to the bottom means by a suitable plastic
welding process, such as ultrasonic welding, spin welding or friction welding. Once
the top means is sealed to the bottom means, assembly is complete. The sealing requirements
for such a container are such that the generated seal must be capable of sustaining
fluid pressure of at least twenty-five pounds per square inch without any substantial
amount of fluid leakage.
[0016] Accordingly, it is an object of the present invention to provide a plastic container
for dispensing fluids under pressure which includes two essential component parts
to be assembled in manufacture.
[0017] It is a further object of the invention to provide a plastic container for dispensing
fluids under pressure which is adapted to utilize an expandable bag to generate the
expulsion pressure within the container.
[0018] It is also an object of the invention to provide a plastic dispensing container utilizing
an expandable bag expulsion system which includes novel strutural features to prevent
the fluid to be expelled from being trapped within the container by the expanding
bag.
[0019] It is yet another object of the invention to provide a plastic dispensing container
which is formed from nestable component parts.
[0020] It is still a further object of the invention to provide a simple, low cost method
for assembling a plastic container for dispensing fluids under pressure.
[0021] Still further objects may become apparent to those skilled in the art by reference
to the accompanying drawings and detailed description set forth below.
[0022] The present invention is illustrated by way of example and not limitation in the
figures of the accompanying drawings in which like reference numerals indicate similar
parts, and in which:
FIG. 1 illustrates a perspective view of the preferred embodiment of a plastic dispensing
container in accordance with the invention;
FIG. 2 illustrates a cross-sectional view of the plastic dispensing container of FIG.
1 taken along line 2-2 of FIG. 1, showing the fluid to be dispensed and the expandable
bag in place within the interior of the container;
FIG. 3 illustrates a top view of the plastic dispensing container of FIG. 1;
FIG. 4 illustrates a cross-sectional view of the plastic dispensing container of FIG.
1 taken along line 4-4 of FIG. 2;
FIG. 5 illustrates a detailed view in perspective of the valve assembly and surrounding
structure of the container of the invention;
FIG. 6 illustrates an exploded view of the structural components of the plastic dispensing
container of FIG. 1, and the expandable bag used therewith;
FIG. 7 illustrates a detailed view in cross-section of the interface between the two
basic components of the container of the invention, in this case the top and bottom
means of the container of FIG. 1;
FIG. 8 illustrates an exploded view of the structural components of the valve assembly
and closure means enclosing the valve assembly;
FIG. 9 illustrates an exploded view of an alternative embodiment of the valve assembly
closure means;
FIG. 9a illustrates an exploded view of a further alternative embodiment of the valve
assembly closure means;
FIG. 10 shows a cross-sectional view of a nested stack of top means of the plastic
dispensing container of the invention shown in FIG. 1;
FIG. 11 shows a cross-sectional view of a nested stack of bottom means of the plastic
dispensing container of the invention shown in FIG 1;
FIG. 12 shows a cross-sectional view of a nested stack of base cup means of the plastic
dispensing container of the invention shown in FIG 1;
FIG. 13 illustrates the assembly sequence for the preferred embodiment of the plastic
dispensing container of the invention; and
FIG. 14 illustrates a cross-sectional view of an alternative container embodiment
utilizing the top means of the plastic dispensing container.
[0023] Referring now to the drawings, the preferred embodiment of the plastic dispensing
container of the invention is shown in FIGS. 1-4, 6 and 9-11, and is designated generally
by reference numeral 10. FIGS. 1-4 show various views of container 10 in its fully-assembled
condition while FIG. 6 shows an exploded view of the structural components of container
10. Container 10 includes two basic structural components, top means 12 and bottom
means 14. Top means 12 generally takes the form of a tapered cap, having a wide open
lower portion 16 and a narrower upper portion 18. Lower portion 16 tapers outwardly
to form the widest dimension of the top means 12, and terminates in a depending flange
20 whose purpose will be hereinafter described.
[0024] Upper portion 18 of top means 12 includes a wide transverse groove, or recess, 22
having a substantially flat bottom wall 24. Bottom wall 24 includes a cylindrical
housing 26 in the center thereof having an aperture 28 therein.
[0025] Cylindrical housing 26, which forms a receptable for the valve assembly, is integrally
molded with the bottom wall 24 of the top 12 and extends upward therefrom. The interior
of cylindrical housing 26 is sized to receive a conventional valve assembly which
may be either of the male or female type. Extending downward from and integrally molded
with bottom wall 24 is a cylindrical guard 27 encircling the valve assembly and which
includes, as described in greater detail below, a holding means for retaining the
valve assembly within the receptable 26.
[0026] Mounted within housing 26 is a spring-loaded aerosol spray valve assembly 30, including
valve stem 32, which as mentioned may be either male or female. Any suitable spray
head (not shown) may be mounted on valve stem 32 to impart flow characteristics which
are appropriate for the fluid being dispensed and the end use to which the fluid is
being put. The width dimension of recess 22 is chosen so that the finger of any user
of the container may easily gain access to the valve means 30. Recess 22 provides
protection for valve means 30 when the container is not in actual use, and also insures
that the fluid being expelled from the container will not travel in a direction which
the user does not intend.
[0027] The manner in which valve assembly 30 is retained within the cylindrical housing
26 and guard 27 is best depicted in FIGS. 8 and 9. Valve assembly 30 is positioned
within cylindrical housing 26 with the stem 32 aligned to extend through aperture
28 and the seal 29 which abuts against the inside of the top wall of receptable 26.
Valve stem 32 includes a hole 32a, so that when the valve stem is depressed by a user,
the hole will be disposed below seal 29, allowing fluid to enter the hole to be dispensed.
Valve assembly 30 is urged into an abutting sealing relation with receptcle 26 by
means of a compression spring 31 which engages the bottom of valve assembly body 30b.
Locking of the valve assembly 30 within the receptable 26 is accomplished by means
of a cap 33 which is fastened to the guard or skirt 27 and which holds compression
spring 31 against valve assembly 30. Cap 33 includes a cylindrical ridge 33a which
serves to center spring 31. In order to allow fluid material to be dispensed to enter
the valve assembly, apertures 62 are provided in guard 27.
[0028] Cap 33 way be bonded to the depending skirt 27 by means of spin or sonic welding
as will be described below. An alternative mounting of cap 33 to skirt 27 is depicted
in FIG. 9. Ears 33c are positioned about the periphery of cap 33 and include grooves
33d which engage and mate with the rib 27a extending about the periphery of skirt
27. An alternative frictional mounting of the cap is depicted in FIG. 9a. A plurality
of frictional gripping members 33e are positioned on the upwardly extending wall 33f
of cap 33. Gripping members 33e, which are preferably metal, engage and bite into
the outer surface of skirt 27 and thus hold spring 31 against valve assembly 30. Cap
33 and wall 33f thereof may further be provided with holes 33g to allow for material
flow from the container into the valve assembly.
[0029] Alternatively, instead of forming guard 27 integrally with top means 12, guard 27
could be formed integrally with cap 33 and suitable mounting means could be provided
on the top means 12, such as those already discussed or variations thereof.
[0030] Utilization of the valve assembly and its mounting within the integrally molded receptacle
26 eliminates the need for the valve mounting cups used in the prior art. Further,
the assembly described herein eliminates the step of crimping the mounting cup to
the container which has heretofore created numerous problems associated with leakage
particularly when the container has been dropped.
[0031] Bottom means 14 comprises a generally cup-shaped vessel which is tapered from a relatively
wide open end 38 to a narrower closed end 40. In the preferred embodiment, closed
end 40 is rounded to seat within a base cup means 42 which will be hereinafter described.
However, it should be understood that closed end 40 may in the alternative have a
flat bottom wall or other configuration that will enable bottom means 14 to stand
upright without support.
[0032] As is best seen in FIGS. 2 and 7, bottom means 14 includes near its open end 38 a
laterally extending shoulder 44 which surrounds the outer periphery of bottom means
14. With reference particularly to FIG. 7, which illustrates the interface between
top means 12 and bottom means 14 prior to welding, shoulder 44 is located at a distance
below the rim 46 of the open end of bottom means 14 which is approximately equal to
the distance which flange 20 of top means 12 extends below rim 48 of top means 12.
Located at the edge of rim 46 of bottom means 14 is a bead 50. In the process of welding
the top and bottom means of container 10 together, bead 50 is partially melted to
form a weld between rim 48 of top means 12 and rim 46 of bottom means 14. When welding
is complete, the lower end of flange 20 rests upon the upper surface of shoulder 44.
The width dimension of shoulder 44 is chosen to match the width of flange 20 so that
a smooth junction is formed when the top and bottom means are welded together.
[0033] Effective joining of the top and bottom portions of =container-10 may be obtained
by spin welding in which the top portion 12 is rotated while bearing against the bottom
portion 14. In this manner, an effective seal may be achieved quickly having a tensile
strength virtually equal to that of the plastic material. Alternatively, sonic or
ultrasonic welding may be employed. In any case, excessive flashing should be trimmed.
In a container of the type described utilizing an expandable bag, the sealing of the
component parts should be sufficient to withstand an internal fluid pressure of at
least 25 pounds per square inch. Such systems have been found to exert pressures in
the range of 2
5 to 90 pounds per square inch.
[0034] The sealing of top means 12 to bottom means 14 thus forms within the container a
fluid impermeable chamber 53. Fluid 54 is shown located within chamber 53 in FIG.
2, as well as an expandable bag 56 such as that described in detail in the aforementioned
U.S. Patent No. 4,376,500.
[0035] In brief, the expandable bag of the above-mentioned patent includes a first group
of compartments which are releasably sealed to the internal side wall of the bag and
which contain a substance such as citric acid in powdered form or in aqueous solution.
Located within the bag external to the first group of compartments is a second substance,
such as sodium bicarbonate, which when reacted in the solution with the citric acid
component will generate carbon dioxide gas. The solvent medium, water for example,
for the aforesaid reaction is contained in a separate rupturable compartment inside
the bag. A time release capsule of the citric acid component is located in the bag
adjacent to the second component, such that it can be dissolved in the solvent medium
when desired to initially activate the gas generating system, i.e., at the point of
final assembly of the bag into the dispensing container 10. As the bag expands initially,
the first group of compartments is successively unsealed from the side wall thereof,
thereby discharging their contents into the solvent containing the second component
and maintaining generation of the gas until the bag reaches its fully expanded condition.
[0036] As bag 56 expands within chamber 53 of container 10, a greater and greater portion
of the volume occupied by fluid 54, and any air initially entrapped within chamber
53, will be displaced until the force exerted by the expanding gases within bag 56
reaches equilibrium with the reactionary force exerted by the fluid 5% and entrapped
air within the chamber 53. Initial actuation of the valve mechanism 30 will permit
the entrapped air within chamber 53 to escape and allow the bag 56 to expand further
to occupy the volume evacuated by the entrapped air. Succeeding actuations of the
valve mechanism 30 will permit fluid 54 to be expelled from chamber 53 under the pressure
exerted by the expanding bag 56 until bag 56 displaces the entire volume of chamber
53 occupied by fluid 54 and all of the fluid has been expelled.
[0037] The expansion of bag 56 within chamber 53 creates the possibility that the bag will
expand to the limits of the upper portion of chamber 53 before expanding to the lower
limits of chamber 53, thereby trapping fluid in that lower portion. In order to prevent
this from happening, the preferred embodiment of container 10 includes along the interior
side wall of bottom portion 14 a longitudinal rib 58. Rib 58 will prevent bag 56 from
expanding completely to the side walls of bottom portion 14, thereby creating an escape
passage for any fluid in the lower portion of chamber 53. The function of rib 58 may
also be served by a tube placed within the bottom portion 14 of the container 10 during
manufacture. Such a tube is shown and described in the above-mentioned U.S. Patent
No. 4,376,500.
[0038] In a similar vein, cylindrical guard 27 which is integrally formed with top means
12 further serves to prevent the expanding bag 56 from obstructing the valve assembly
30. Cylindrical guard 27 includes a plurality of grooves 62 therein to provide passage
for fluid 54 to reach the valve assembly 30.
[0039] As mentioned earlier, the bottom means 14 of the preferred embodiment of container
10 has a rounded lower portion 40 which seats within a base cup means 42 as shown
in FIG. 2. Base cup means 42 includes a bevelled interior wall 64 which is formed
to snugly fit against the tapered side walls of bottom means 14. The lower portion
of base cup means 42 forms an annular inwardly sloping seat 66 which supports the
rounded bottom portion 40 of bottom means 14. Bevelled wall 64 and annular seat 66
cooperate to position bottom cup means 14 in an upright position.
[0040] All of the structural components of container 10 hereinbefore described (with the
exception of certain internal parts of valve assembly 30 and the spring 31) are formed
of any one of a number of synthetic plastics which are both fluid impermeable and
strong enough to withstand the pressure developed within the container. Among the
plastics from which the container of the invention may be formed are polyethylene
terephthalate, polyvinyl chloride and the polyacronitriles. The structural components
of the container may be made by any one of a number of processes for forming plastic
parts, such as blow molding, extrusion or injection molding.
[0041] As shown in FIGS. 10, 11 and 12, top means 12, bottom means 14 and base cup means
42 of the preferred embodiment of container 10 are each shaped so as to be stored
in nested stacks. The nestable shapes of top means 12, bottom means 14 and base cup
means 42 permit storage of those components prior to manufacture in relatively small
areas, thus efficiently utilizing the apace available for storage and lowering warehousing
costs. The nestable shapes also promote easier feeding of the components on the assembly
line during manufacture.
[0042] The manufacturing assembly sequence for the preferred embodiment of the container
of the invention is illustrated from left to right in FIG. 13. Bottom cup means 42
is first fed from a nested stack onto a moving belt or other conveying device, and
then delivered to Station (1). At Station (1), a bottom means 14 is fed from a nested
stack and seated in base cup means 42. The resulting subassembly is then delivered
to Station (2), where bottom means 14 is filled with fluid which is to be dispensed.
After being filled with fluid, the subassembly is conveyed to Station (3), where an
expandable bag 56 is inserted from a magazine into bottom means 14. Since the bottom
means 14 has a wide opening extending for its entire inner diameter, insertion of
the expandable bag 56 is accomplished without requiring crushing. Next, the subassembly
is conveyed to Station (4), where top means 12 is fed from a magazine containing a
nested stack of that component onto the open end of bottom means 14. At the next Station,
Station (5), top means 12 is welded to bottom means 14 by one of a number of suitable
plastic welding techniques, such as ultrasonic welding, friction welding or spin welding.
The completed container 10 is then conveyed to a packing station and then prepared
for shipment.
[0043] Appropriate modifications, which will be obvious to those skilled in the art, may
be made to the assembly sequence illustrated in FIG. 13 to accommodate containers
of different shapes. For example, as previously mentioned, bottom means 14 may have
a flat bottom wall enabling it to stand upright without base cup means 42, thereby
eliminating base cup means 42 from the assembly sequence. Alternatively, bottom means
14 or top means 12 may have non-nestable shapes which would require them to be placed
or fed onto the assembly line by a different method than that shown in FIG. 13.
[0044] The cap or top means 12 of the container 10 herein may readily be adapted for use
in association with a refill pouch of the type disclosed in applicant's copending
application Serial No. 365,552, filed on April 5, 1982 and entitled "A Dispensing
System And A Refill Pouch." With particular reference to FIG. 14, the top means 92
of container 90 is generally of the same construction as that previously described
except that a different manner of sealing the two basic components of the container
together is provided. The lower portion of top means 92 of container 90 includes an
extended depending flange 96 which is provided with screw threads on its interior
wall. Mating screw threads are provided on the exterior surface of the upper portion
of bottom means 94. An o-ring seal may be utilized in association with the threads,
to secure an appropriate seal.
[0045] The bottom means 94 again includes the expandable bag 95, depicted in FIG. 14 in
a partially expanded state, including pressure generating means 98 and rupturable
compartment 100 for initiating gas generation. A tube 101 may be provided so that
material to be dispensed at the bottom of bottom means 94 is not "pinched off" by
the expandable bag 95. As explained in greater detail in Application Serial No. 365,552,
the material to be dispensed is housed within an outer pouch 97, as is also the expandable
bag 95. Outer pouch 97 preferably conforms to the shape of bottom means 94 and top
means 92, as shown. The top of outer pouch 97 is open to allow fluid material to be
dispensed to be in communication with the valve assembly. Such an opening may be made
by removal of a tear strip as explained in Application Serial No. 365,552 or by an
appropriate puncturing of the outer pouch 97. Once all of the material has been dispensed,
container 90 may be opened by removal of the top means 92 and a new refill inserted
as described in Serial No. 365,552, the disclosure of which is herein incorporated
by reference.
[0046] This invention has been described in terms of specific embodiments set forth in detail,
but it should be understood that these are by way of illustration only and that the
invention is not necessarily limited thereto. Modifications and variations will be
apparent from this disclosure and may be resorted to without departing from the spirit
of this invention, as those skilled in the art will readily understand. Accordingly,
such variations and modifications of the disclosed invention are considered to be
within the purview and scope of this invention and the following claims.
1. A container for dispensing fluid contained therein which comprises:
a lower portion formed of a pressure-resistant fluid-impermeable synthetic plastic
material, said lower portion having a bottom closed end, and side walls extending
upwardly from said closed end and terminating to form a substantially fully open end;
expandable bag means adapted to be inserted into the open end of said lower portion
of said container without any substantial crushing thereof;
an upper portion formed of a pressure-resistant fluid-impermeable synthetic plastic
material, said upper portion having a top end, side walls extending downwardly from
said top end and terminating to form a substantially fully open end sized for mating
with said open end of said lower portion;
sealing means for joining said lower portion and said upper portion to form a single
fluid-impermeable chamber;
dispensing valve means for releasing fluid from said chamber;
receptacle means molded in said top end of said upper portion adapted to receive said
dispensing valve means; and
closure means for retaining said valve means in said receptable means and including
openings therein to permit the fluid to pass from said chamber to said valve means,
said closure means being disposed about an end of the valve means in communication
with the fluid within said chamber to restrain said expandable bag means from interfering
with said valve means and the dispensing of fluid therefrom.
2. A container in accordance with Claim 1 which further includes rib means integrally
formed along the interior side wall of said lower portion for preventing said fluid
from becoming trapped within said chamber by said expandable bag means as said bag
mean expands.
3. A container in accordance with claim 1 or claim 2 wherein at least one of said
upper and lower portions has a nestable shape.
4. A container in accordance with any of claims 1 to 3 wherein said lower portion
is welded to said upper portion forming a seal capable of sustaining a fluid pressure
of at least twenty-five pounds per square inch without any substantial amount of fluid
leakage.
5. A container in accordance with any of claims! to 4 wherein said lower portion has
a rounded closed end and said container further includes:
base cup means into which said rounded closed end of said lower portion is disposed,
for supporting said lower portion in an upright position.
6. A container in accordance with any of claims 1 to 5 which further includes rib
means integrally formed along the interior sidewall of said top portion of said container
for preventing said fluid from becoming trapped within said chamber.
7*A container in accordance with any of claims 1 to 6 wherein said receptacle means
comprises an upwardly extending generally cylindrical housing adapted to conform to
the body of said valve means, said valve means having an upwardly extending valve
stem, said cylindical housing having an aperture in the upper end thereof to facilitate
passing of the valve stem therethrough.
8. A container in accordance with Claim 7 which further includes resilient means disposed
between said closure means and said valve means for urging said valve means into a
sealing relation with an upper end of said cylindrical housing.
9. A container in accordance with Claim 8 wherein said closure means comprises depending
guard means downwardly extending into said chamber from said receptacle means molded
in said top end of said upper portion and forming a lower edge, and cap means secured
to said lower edge of said guard means.
10. A container in accordance with Claim 9 which further includes frictional holding
means securing said guard means and said cap means.
11. A top dispensing member for use with fluid dispensing containers having an expandable
bag means therein for exerting pressure on fluid in the container to be dispensed
which comprises:
a molded member formed of a pressure-resistent fluid-impermeable synthetic plastic
material having a top end, side walls extending downwardly from said top end and terminating
to form a substantially fully open end sized for mating with an open end of a lower
portion of the container;
dispensing valve means for releasing fluid from the container;
receptable means molded in said top end of said upper portion adapted to receive said
dispensing valve means;
closure means for retaining said valve means in said receptacle means and including
openings therein to permit the fluid to pass from the container to said valve means,
said closure means being disposed about an end of said valve means in communication
with the fluid within the container to restrain the expandable bag means from interfering
with said valve means and the dispensing of fluid therefrom; and
resilient means disposed between said closure means and said valve means for urging
said valve means into a sealing relation with said upper end of said cylindrical housing.
12. A top dispensing member in accordance with claim 11 wherein said receptacle means
comprises an upwardly extending generally cylindrical housing, the interior of which
is adapted to conform to the body of said valve means, said valve means having an
upwardly depending valve stem, said cylindrical housing having an aperture in the
upper end thereof to facilitate passing of said valve stem therethrough.
13. A top dispensing member in accordance with claim 11 or 12 wherein said closure
means comprises depending guard means downwardly extending from said receptable means
forming a lower edge and cap means secured to said guard means.
14. A top dispensing member in accordance with claim 13 which further includes frictional
holding means securing said cap means and said guard means.
15. A method of manufacturing a plastic container for dispensing a fluid contained
therein under pressure comprising the steps of:
delivering to a first station a lower portion of said container comprising a vessel
having a substantially fully open end at the upper end thereof, said lower portion
being formed of a pressure-resistant fluid-impermeable synthetic plastic material;
conveying said lower portion to a second station;
filling said lower portion with said fluid at said second station to less than capacity;
conveying said lower portion to a third station;
inserting expandable bag means into the open end of said fluid-filled lower portion
at said third station without any substantial crushing thereof;
conveying said lower portion to a fourth station;
delivering an upper portion comprising a vessel having a substantially fully open
end sized for mating with said open end of said lower portion to said fourth station,
said upper portion being formed of a pressure-resistent fluid-impermeable synthetic
plastic material and including manually actuable valve means;
mating said upper portion with the open end of said lower portion; and
sealing said upper portion to said lower portion to effect a seal capable of sustaining
an internal fluid pressure of at least twenty-five pounds per square inch without
any substantial amount of fluid leakage.
16. The method of Claim 15 wherein said step of sealing said upper portion to said
lower portion comprises welding each of said portions to one another about the entire
periphery thereof.
17. The method of Claim 16 wherein said step of delivering to a first station a lower
portion of a container comprises the step of removing said lower portion from a nested
stack of said lower portions.
18. The method of claim 16 or claim 17 wherein said step of delivering an upper portion
to said fourth station comprises the step of removing said upper portion from a nested
stack of said upper portions.
19. The method of any of claims 15 to 18 wherein said step of inserting expandable
bag means comprises the steps of severing said bag means from a strip of similar bag
means and dropping said bag means into the open end of said lower portion.
20. The method of any of claims 15 to 19 which further includes the step of providing
a base cup into which said lower portion of said container is delivered for supporting
said lower portion in an upright position.
21. A method of manufacturing a plastic container for dispensing a fluid contained
therein under pressure comprising the steps of:
delivering to a first station a lower portion comprising a vessel having an open end
from a nested stack of such lower portions, said lower portions being formed of a
pressure-resistant fluid-impermeable synthetic plastic material;
conveying said lower portion to a second station;
filling said lower portion with said fluid at said second station to less than capacity;
conveying said lower portion to a third station;
inserting expandable bag means into said fluid-filled lower portion at said third
station;
conveying said lower portion to a fourth station;
delivering an upper portion to said fourth station from a nested stack of such upper
portions, said upper portion being formed of a pressure-resistant fluid-impermeable
synthetic plastic material and including manually actuable valve means;
placing said upper portion onto the open end of said lower portion at said fourth
station;
conveying said lower portion and upper portion to a fifth station; and
sealing said upper portion to said lower portion at said fifth station to effect a
seal capable of sustaining an internal fluid pressure of at least twenty-five pounds
per square inch without any substantial amount of fluid leakage.