Dispensing container with follower discharge assistant

Claim 2

A molded plastic piston of unitary construction for use in tubular dispensers comprising: a circular flexible obturating wall with a flat outer or front surface deformable outwardly, i.e., forwardly, under force applied centrally thereof; a generally cylindrical flange or skirt integral with the obturating wall at the circumference thereof and extending away from the wall in only a rearward direction from the top surface, and adapted to slide within a tubular member and properly orient the obturating wall therein, said flange or skirt abruptly increasing in outside diameter at a location remote from the wall and terminating in a circumferential portion the outside diameter of which is greater than that of the obturating wall and major portion of the flange or skirt to provide a sliding seal at the end of the flange or skirt between the piston and a tubular dispenser; and a central hub integral with and extending rearwardly from the obturating wall for securing the end of a push member to the piston.

Claim 3

A piston as set forth in claim 1 wherein the piston is made of high density polyethylene, and the diameter of the obturating wall is on the order of 50 to 100 times as great as the average thickness of the wall to provide sufficient flexibility so that the wall will dome when pressure is applied at the hub during use.

Claim 4

A piston as set forth in claim 1 wherein the diameter of the obturating wall is between 4 and 4.5 times as great as the axial length of the skirt or flange.

Claim 5

A piston as set forth in claim 1, wherein said circumferential portion is formed by an outward curve or flare of the flange or skirt.

Claim 6

A piston as set forth in claim 4 wherein the outward curve or flare of the skirt is small, being not more than 0.020 inch greater in diameter than the obturating wall when the top surface of said wall is in a flat condition.

Claim 7

A molded plastic piston of unitary construction for use in tubular dispensers for ice cream or the like, comprising: a circular flexible obturating wall with a flat outer or front surface deformable outwardly, i.e., forwardly, under force applied centrally thereof; a generally cylindrical flange or skirt integral with the obturating wall at the circumference thereof, forming a peripheral juncture therewith that has a rounded transverse contour, extending away from the wall in only a rearward direction from the top surface, and adapted to slide within a tubular member and properly orient the obturating wall therein, said flange or skirt abruptly increasing in outside diameter at a location remote from the wall and terminating in a circumferential portion the outside diameter of which is greater than that of the obturating wall and major portion of the flange or skirt to provide a sliding seal at the end of the flange or skirt between the piston and a tubular dispenser; and a central hub integral with and extending rearwardly from the obturating wall for securing the end of a push member to the piston; said obturating wall having a central area extending radially beyond said hub and terminating short of said annular flange or skirt that is of greater thickness than the remainder of said wall.

Claim 8

A molded plastic piston of unitary construction for use in tubular dispensers for ice cream or the like, comprising: a circular flexible obturating wall with a flat outer or front surface deformable outwardly, i.e., forwardly, under force applied centrally thereof; a generally cylindrical flange or skirt integral with the obturating wall at the circumference thereof, forming a peripheral juncture therewith that has a rounded transverse contour, extending away from the wall in only a rearward direction from the top surface, and adapted to slide within a tubular member and properly orient the obturating wall therein, said flange or skirt abruptly increasing in outside diameter at a location remote from the wall and terminating in a circumferential portion the outside diameter of which is greater than that of the obturating wall and major portion of the flange or skirt to provide a sliding seal at the end of the flange or skirt between the piston and a tubular dispenser; and a central hub integral with and extending rearwardly from the obturating wall for securing the end of a push member to the piston; said obturating wall having a central area extending radially beyond said hub and terminating short of said annular flange or skirt that is of greater thickness than the remainder of said wall.

Claim 9

A piston of unitary construction for use in tubular dispensers for ice cream or the like comprising: a circular flexible obturating wall with a flat outer or front surface, deformable outwardly, i.e., forwardly, under force applied centrally thereof, to facilitate sliding of the piston within a tubular member; a flange or skirt integral with and extending from the obturating wall at the circumference thereof in a rearward direction and having a major cylindrical portion adjacent the obturating wall that, at a location remote from said wall, steeply or abruptly increases in diameter to an enlarged circumferential portion, said skirt being adapted to fit in slidable relationship within a tubular member and properly orient the obturating wall therein, and said enlarged circumferential portion being adapted to provide a sliding seal between the flange or skirt and the piston and tubular member; and a central hub extending rearwardly from the obturating wall for securing the end of a push member to the piston.

Claim 10

A piston of unitary construction for use in tubular dispensers for ice cream or the like comprising: a circular flexible obturating wall with a flat outer or front surface, deformable outwardly, i.e., forwardly, under force applied centrally thereof, to facilitate sliding of the piston within a tubular member; a flange or skirt integral with and extending from the obturating wall at the circumference thereof in a rearward direction and having a major cylindrical portion adjacent the obturating wall that, at a location remote from said wall, steeply or abruptly increases in diameter to an enlarged circumferential portion, said skirt being adapted to fit in slidable relationship within a tubular member and properly orient the obturating wall therein, and said enlarged circumferential portion being adapted to provide a sliding seal between the flange or skirt and the piston and tubular member; and a central hub extending rearwardly from the obturating wall for securing the end of a push member to the piston.

Claim 11

In combination, a tubular container and a piston within said container, said container having an open end with an inwardly extending peripheral burr that reduces the size of said open end with respect to the inside cross-sectional dimensions of the container, and said piston having a circular flexible obturating wall with a normally flat outer or front surface deformable outwardly, i.e., forwardly, under force applied centrally thereof, a central hub extending rearwardly from the obturating wall, and a peripheral skirt or flange integral with and extending from the obturating wall at the circumference thereof in a rearward direction and having a major cylindrical portion adjacent the obturating wall that, at a location remote from said wall, steeply or abruptly increases in diameter to an enlarged circumferential end portion, said skirt or flange being slidably received within the container, and the circumferential end portion being more readily movable past said burr in a direction of movement in which the skirt or flange follows the obturating wall, as when the piston is inserted obturating-wall-first into said open end, than in the opposite direction, in which movement of the piston is substantially obstructed by said burr to inhibit removal of the piston from the container.

Claim 12

In combination, a tubular container and a piston within said container, said container having an open end with an inwardly extending peripheral burr that reduces the size of said open end with respect to the inside cross-sectional dimensions of the container, and said piston having a circular flexible obturating wall with a normally flat outer or front surface deformable outwardly, i.e., forwardly, under force applied centrally thereof, a central hub extending rearwardly from the obturating wall, and a peripheral skirt or flange integral with and extending from the obturating wall at the circumference thereof in a rearward direction and having a major cylindrical portion adjacent the obturating wall that, at a location remote from said wall, steeply or abruptly increases in diameter to an enlarged circumferential end portion, said skirt or flange being slidably received within the container, and the circumferential end portion being more readily movable past said burr in a direction of movement in which the skirt or flange follows the obturating wall, as when the piston is inserted obturating-wall-first into said open end, than in the opposite direction, in which movement of the piston is substantially obstructed by said burr to inhibit removal of the piston from the container.