Vertical stacker

Claim 2

A one-piece, thin wall, disposable, plastic article comprising an outwardly inclined axially extending wall and a transverse wall integral with the axially extending wall, and a nesting facility formed in the axially extending wall, said nesting facility having a lower external shoulder and an upper internal shoulder, a substantially vertical disposed intermediate wall section interconnecting the inner radial edge of one shoulder and the outer radial edge of the other, a plurality of substantially vertically disposed protrusions formed in the intermediate wall extending the full axial height thereof, said protrusions being spaced apart about the intermediate wall a distance substantially equal to the circumferential width of the protrusions so that each protrusion has a circumferential width equal to the circumferential width of each intermediate wall portion between each protrusion, with said protrusions acting to provide a stacking interference at equally spaced portions about the circumference of the article when it is stacked with a similar article out of circumferential phase therewith, said intermediate wall section being free of undercuts between the upper and lower shoulders.

Claim 3

In combination with the article of claim 1, at least one additional article nested therewith and characterized as set forth in said claim, said articles being further characterized by at least some of said articles having different numbers of protrusions.

Claim 4

A one-piece, thin wall, disposable, plastic article as defined in claim 1 further characterized by said article being a container and said intermediate wall section lying in the axially extending wall.

Claim 5

A one-piece, thin wall, disposable, plastic article comprising, an axially extending wall and a transverse wall integral with the axially extending wall, a nesting facility formed in a recess in the transverse wall, said nesting facility having, a lower external shoulder and an upper internal shoulder, a substantially vertically disposed intermediate wall section defining one side of said recess and interconnecting the inner radial edge of one shoulder and the outer radial edge of the other, a plurality of substantially vertically disposed protrusions formed in the intermediate wall extending the full axial height thereof, said protrusions being spaced apart about the intermediate wall a distance substantially equal to the circumferential width of the protrusions so that each protrusion has a circumferential width equal to the circumferential width of each intermediate wall portion between each protrusion, with said protrusions acting to provide a stacking interference at equally spaced portions about the circumference of the article when it is stacked with a similar article out of circumferential phase therewith, said intermediate wall section being free of undercuts between the upper and lower shoulders.

Claim 6

A one-piece, thin wall, disposable, plastic article comprising, an axially extending wall and a transverse wall integral with the axially extending wall, a nesting facility formed in a recess in the transverse wall, said nesting facility having, a lower external shoulder and an upper internal shoulder, a substantially vertically disposed intermediate wall section defining one side of said recess and interconnecting the inner radial edge of one shoulder and the outer radial edge of the other, a plurality of substantially vertically disposed protrusions formed in the intermediate wall extending the full axial height thereof, said protrusions being spaced apart about the intermediate wall a distance substantially equal to the circumferential width of the protrusions so that each protrusion has a circumferential width equal to the circumferential width of each intermediate wall portion between each protrusion, with said protrusions acting to provide a stacking interference at equally spaced portions about the circumference of the article when it is stacked with a similar article out of circumferential phase therewith, said intermediate wall section being free of undercuts between the upper and lower shoulders.

Claim 7

A oNe-piece, thin wall, disposable, plastic article as defined in claim 4 further characterized by said article being a lid and having a flange extending outwardly from said axially extending wall and having a skirt extending downwardly from the outer edge of the flange, said axially extending wall, flange, and skirt enclosing the rim of a container when fitted on it.

Claim 8

A one-piece, thin wall, disposable, plastic container comprising a bottom and an outwardly inclined upwardly extending side wall integrally formed from a thin sheet of plastic material and joined at a bottom edge, said container having a nesting facility characterized by: a lower external shoulder formed in the side wall that may be coincident with the container bottom and an upper internal shoulder spaced above the lower shoulder in said side wall, a substantially vertically disposed intermediate wall section interconnecting the inner radial edge of the upper shoulder and the outer radial edge of the lower shoulder, said intermediate wall having an inner diameter at the upper shoulder at least as great as the inner diameter at the lower shoulder, a plurality of protrusions formed in the intermediate wall extending the full axial height thereof, said protrusions being spaced apart about the intermediate wall a distance substantially equal to the circumferential width of the protrusions so that each protrusion has a circumferential width equal to the circumferential width of each intermediate wall portion between each protrusion, with said protrusions acting to provide a stacking interference at equally spaced portions about the circumference of the article when it is stacked with a similar article out of circumferential phase therewith, said intermediate wall being free of undercuts between the upper and lower shoulders.

Claim 9

A one-piece, thin wall, disposable, plastic container comprising a bottom and an outwardly inclined upwardly extending side wall integrally formed from a thin sheet of plastic material and joined at a bottom edge, said container having a nesting facility characterized by: a lower external shoulder formed in the side wall that may be coincident with the container bottom and an upper internal shoulder spaced above the lower shoulder in said side wall, a substantially vertically disposed intermediate wall section interconnecting the inner radial edge of the upper shoulder and the outer radial edge of the lower shoulder, said intermediate wall having an inner diameter at the upper shoulder at least as great as the inner diameter at the lower shoulder, a plurality of protrusions formed in the intermediate wall extending the full axial height thereof, said protrusions being spaced apart about the intermediate wall a distance substantially equal to the circumferential width of the protrusions so that each protrusion has a circumferential width equal to the circumferential width of each intermediate wall portion between each protrusion, with said protrusions acting to provide a stacking interference at equally spaced portions about the circumference of the article when it is stacked with a similar article out of circumferential phase therewith, said intermediate wall being free of undercuts between the upper and lower shoulders.

Claim 10

A one-piece, thin wall, disposable, plastic container as described in claim 6 further characterized by each of said protrusions being defined by an arcuate wall whose center is coincident with the axis of the container, said protrusions being further characterized by radii which merge smoothly into the arcuate wall and define sharp corners with the intermediate wall.

Claim 11

In combination with the container of claim 6, at least one additional container nested therewith and characterized as set forth in said claim, said containers being further characterized by at least some of said containers having different numbers of protrusions.