Variable volume container for fluids

Claim 2

A variable volume plastic container for fluids capable of collapsing in a controlled and uniform manner, comprising top and bottom portions; flexible means responsive to pressure changes to vary the container volume, said flexible means including a pair of opposed flexible side walls extending between and integrally connected with said top and bottom portions; and rigidifying means for supporting said flexible means and for maintaining said top and bottom portions in vertically spaced relationship, said rigidfying means including a pair of opposed relatively rigid side walls connected with said top and bottom portions and said flexible means to completely enclose the container volume, each said rigid side wall including a pair of integrally connected planar walls forming a V-shaped pleat extending into the container along the entire vertical distance between said top and bottom portions, said planar walls forming an intersection at a predetermined fixed angle, whereby the lateral edges of said flexible side walls are maintained in a generally constant vertical orientation as said flexible side walls are flexed inwardly anD outwardly to vary the container volume in response to fluids being inserted and withdrawn therefrom.

Claim 3

A variable volume container as claimed in claim 1, wherein said predetermined angle is greater than 5* but less than 175*.

Claim 4

A variable volume container as claimed in claim 1, wherein said fixed predetermined angle is greater than 10* but less than 90*.

Claim 5

A variable volume container as claimed in claim 1, wherein said fixed predetermined angle is greater than 20* but less than 60*.

Claim 6

A variable volume container as claimed in claim 1, wherein the perpendicular distance between said intersections and the outer edge of each said planar wall is greater than one-tenth but less than one-half the overall lateral width of the container.

Claim 7

A variable volume container as claimed in claim 1, wherein each said planar wall varies in thickness from a maximum adjacent said intersection to a minimum adjacent the outer edge thereof.

Claim 8

A variable volume container as claimed in claim 6, wherein said top and bottom portions and said side walls form an integrally molded, one-piece unitary body.

Claim 9

A variable volume container as claimed in claim 7, wherein said unitary body is formed from a material selected from the group consisting of polypropylene, copolymers of polypropylene, polyethylene, copolymers of polyethylene, and polyvinyl chloride.

Claim 10

A variable volume container as claimed in claim 7, wherein said unitary body is formed of polypropylene.

Claim 11

A variable volume container as claimed in claim 9, wherein the maximum thickness of said planar walls is greater than 0.012 inches but less than 0.06 inches and the minimum thickness of said planar walls is approximately 0.005 inches.

Claim 12

A variable volume container as claimed in claim 1, wherein said opposed flexible side walls move toward a first position in which said side walls are concave inwardly in direct contact with the entire inner surfaces of said planar walls as fluid is withdrawn from the container and toward a second position in which said side walls are convexed outwardly as fluid is introduced into the container.

Claim 13

A variable volume container as claimed in claim 11, wherein the lateral length of each said flexible side wall in said first position is equal to the lateral length of said flexible side wall in said second position.

Claim 14

A variable volume container as claimed in claim 11, wherein said flexible side walls and said planar walls are integrally connected by means of a flexible membrane having radius of curvature substantially greater than the thickness of said flexible membrane.

Claim 15

A variable volume container as claimed in claim 11, wherein said flexible side walls while in said first position are in direct contact over the portion thereof extending between said intersections of said planar walls.

Claim 16

A variable volume container as claimed in claim 1, wherein said top portion includes supporting means for supporting said container in a vertically depending manner.

Claim 17

A variable volume container as claimed in claim 15 wherein said supporting means includes a tab containing an opening adapted to receive a support member.

Claim 18

A variable volume container as claimed in claim 15 wherein said supporting means includes a knob having an enlarged upper portion.

Claim 19

A variable volume container as claimed in claim 1, wherein said bottom portion includes closure means for allowing fluids to be introduced or removed from the container.

Claim 20

A variable volume container as claimed in claim 18, wherein said closure means includes at least one open port and cap means for removably closing said port.

Claim 21

A variable volume container as claimed in claim 19, wherein said cap means includes a resilient stopper and an overcap for securing the resilient stopper to said open port.

Claim 22

A variable volume container as claimed in claim 1, wherein each of said top and bottom portions includes a rigid rectanguLar end member and flexible connective means for connecting the periphery of said end member with said flexible side walls and said planar walls, said connective means including a plurality of interconnected substantially planar panel sections adapted to fold inwardly to move said top and bottom portions toward a first position adjacent the upper and lower edges of said side walls, respectively, as fluid is removed from the container and toward a second position spaced from the upper and lower edges of said side walls, respectively, as fluid is introduced into the container.

Claim 23

A variable volume container as claimed in claim 1, wherein said top and bottom portions are formed by vertical extensions of said planar panels and said flexible side walls, said planar panel extensions being integrally connected to form V-shaped pleats across the top and bottom of the container, said V-shaped pleats extending into the container to a minimum depth adjacent the central axis of the container and to a maximum depth adjacent the lateral sides thereof.

Claim 24

A variable volume container as claimed in claim 1 wherein said top and bottom portions each include, an end panel, extensions of said flexible side walls being integrally connected with the periphery of said end panels, and a pair of V-shaped panels integrally connected with said pair of rigid side walls at the terminal ends thereof, respectively, said V-shaped panels being arranged in a plane perpendicular to said planar walls, each said end panel being movable toward a first extended position in which said flexible side walls and said flexible side wall extensions form smooth continuous concave surfaces and in which said V-shaped panels are arranged in a plane forming a 45* angle with the central axis of the container as fluid is inserted into said container and toward a second position in which said extensions of said side walls and said V-shaped panels are folded against said end panel as fluid is withdrawn from the container.

Claim 25

A unitary, integrally molded variable volume container for fluids capable of collapsing in a controlled and uniform manner, comprising top and bottom portions, flexible means responsive to pressure changes to vary the container volume, said flexible means including a pair of opposed flexible side walls extending between and integrally connected with said top and bottom portions, rigidifying means for supporting said flexible means and for maintaining said top and bottom portions in vertically spaced relationship, said rigidifying means including a pair of opposed, relatively rigid side walls connected with said top and bottom portions and with said pair of flexible side walls, each said rigid side wall including a pair of integrally connected planar walls forming a V-shaped pleat, the intersection of said planar walls forming an angle greater than 20* but less then 60*, said V-shaped pleat extending into the container along the entire vertical distance between said top and bottom portions, each said planar wall being connected along the outer edge thereof with one of said flexible side walls, each said planar wall further varying in thickness from a maximum adjacent said corresponding intersection to a minimum adjacent the outer edge thereof, said opposed flexible side walls being movable toward a first position in which said side walls are concaved inwardly in direct contact with the entire inner surfaces of said planar walls and in direct contact with each other over the portions of said flexible side walls extending between said intersections of said planar walls as fluid is withdrawn from the container and toward a second position in which said side walls are convexed outwardly as fluid is introduced into the container.

Claim 26

A unitary, integrally molded variable volume container for fluids capable of collapsing in a controlled and uniform manner, comprising top and bottom portions, flexible means responsive to pressure changes to vary the container volume, said flexible means including a pair of opposed flexible side walls extending between and integrally connected with said top and bottom portions, rigidifying means for supporting said flexible means and for maintaining said top and bottom portions in vertically spaced relationship, said rigidifying means including a pair of opposed, relatively rigid side walls connected with said top and bottom portions and with said pair of flexible side walls, each said rigid side wall including a pair of integrally connected planar walls forming a V-shaped pleat, the intersection of said planar walls forming an angle greater than 20* but less then 60*, said V-shaped pleat extending into the container along the entire vertical distance between said top and bottom portions, each said planar wall being connected along the outer edge thereof with one of said flexible side walls, each said planar wall further varying in thickness from a maximum adjacent said corresponding intersection to a minimum adjacent the outer edge thereof, said opposed flexible side walls being movable toward a first position in which said side walls are concaved inwardly in direct contact with the entire inner surfaces of said planar walls and in direct contact with each other over the portions of said flexible side walls extending between said intersections of said planar walls as fluid is withdrawn from the container and toward a second position in which said side walls are convexed outwardly as fluid is introduced into the container.

Claim 27

A container as claimed in claim 24, wherein the perpendicular distance between said intersection and the outer edge of each said planar wall is greater then one-tenth but less then one-half the overall lateral width of said container.

Claim 28

A container as claimed in claim 24, wherein the lateral length of each said flexible side wall in said first position is equal to the lateral length of said flexible side wall in said second position.

Claim 29

A container as claimed in claim 26, wherein said flexible side walls and said planar walls are integrally connected by means of a flexible membrane having a radius of curvature substantially greater than the thickness of said flexible membrane.

Claim 30

A container as claimed in claim 27, wherein the container is formed of polypropylene.

Claim 31

A container as claimed in claim 28, wherein the maximum thickness of said planar walls is greater than 0.012 inches but less than 0.06 inches and the minimum thickness of said planar walls is approximately 0.005 inches.

Claim 32

A container as claimed in claim 27, wherein the container if formed of polyvinyl chloride.