US3896934A — Free flow, interlocking packing material of low b…

Claim 1

Independent Claim 168 words

A free flow, interlocking packing material of low bulk density, particularly adapted to providing maximum absorption of shock while preventing migration of relatively heavy packed items therethrough, comprising a plurality of individual packing units formed of a foamed substantially rigid expanded plastic material possessing sufficient internal strength to be self-sustaining under normal handling but capable of substantial crushing in response to external force, each of said indIvidual packing units consisting of a central substantially cylindrical annular portion and two outwardly curling annular portions substantially permanently secured to said central portion and to one another at a peripheral portion thereof, said portions being characterized by a foam structure which has been expanded substantially greater in a radial direction than in an exial direction so as to provide enlarged wedge-shaped openings between said portions, the foam structure of said packing units at said peripheral portion being relatively stronger in the axial direction and being sufficiently rigid to prevent articulation between said outwardly curling portions and said central substantially cylindrical portion.

Claim 2

Dependent Claim 168 words

A free flow, interlocking packing material of low bulk density, particularly adapted to providing maximum absorption of shock while preventing migration of relatively heavy packed items therethrough, comprising a plurality of individual packing units formed of a foamed substantially rigid expanded plastic material possessing sufficient internal strength to be self-sustaining under normal handling but capable of substantial crushing in response to external force, each of said indIvidual packing units consisting of a central substantially cylindrical annular portion and two outwardly curling annular portions substantially permanently secured to said central portion and to one another at a peripheral portion thereof, said portions being characterized by a foam structure which has been expanded substantially greater in a radial direction than in an exial direction so as to provide enlarged wedge-shaped openings between said portions, the foam structure of said packing units at said peripheral portion being relatively stronger in the axial direction and being sufficiently rigid to prevent articulation between said outwardly curling portions and said central substantially cylindrical portion.

Claim 3

Dependent Claim 53 words

A packing material as in claim 1 wherein said central annular portion is substantially in the form of a right cylinder, and said outwardly curling annular portions have a dimension along the axis thereof, between the outer edges of said curled portions substantially equal to the outer diameter of said central cylindrical portion.

Claim 4

Dependent Claim 37 words

A packing material as in claim 1 wherein said individual packing units are initially cut from an elongate tubular length of foamed expanded plastic which is partially cut through to provide adjacent, peripherally bonded substantially cylindrical portions.

Claim 5

Dependent Claim 57 words

A packing material as in claim 3 wherein said substantially cylindrical portions are secured to one another in a zone of longitudinally stretched foamed plastic which, on subsequent expanding, provides the foamed structure with said characteristic of being relatively stronger in the axial direction while being sufficiently rigid to prevent articulation of said outwardly curled annular portions.

Claim 6

Dependent Claim 232 words

As an article of manufacture, a shipping carton for frangible items, such carton being substantially completely filled with a packing mass comprised of a plurality of individual packing units formed of a foamed substantially rigid expanded plastic material, said plastic material possessing sufficient internal strength to be self-sustaining under normal handling but capable of substantial crushing in response to external force, each of said individual packing units consisting of a central substantially cylindrical annular portion and two outwardly curling annular portions substantially permanently secured to said central portion and to one another at a peripheral portion thereof, said portions being characterized by a foam structure which has been expanded substantially greater in a radial direction than in an axial direction so as to provide enlarged wedge-shaped openings between said portions, the foam structure of said packing units at said peripheral portion being relatively stronger in the axial direction and sufficiently rigid to prevent articulation between said outwardly curling portion and said central substantially cylindrical portion, the positioning of said annular portions providing wedge-shaped openings adapted to interlock with at least one of the other said individual packing units, said interlocking extending throughout the said packing mass to cooperatively prevent migration of an article packed therein, said respective curling and cylindrical annular portions presenting a shape configuration wherein outermost portions thereof are substantially equidistant from the geometric centers of said individual packing units.

Claim 7

Dependent Claim 232 words

As an article of manufacture, a shipping carton for frangible items, such carton being substantially completely filled with a packing mass comprised of a plurality of individual packing units formed of a foamed substantially rigid expanded plastic material, said plastic material possessing sufficient internal strength to be self-sustaining under normal handling but capable of substantial crushing in response to external force, each of said individual packing units consisting of a central substantially cylindrical annular portion and two outwardly curling annular portions substantially permanently secured to said central portion and to one another at a peripheral portion thereof, said portions being characterized by a foam structure which has been expanded substantially greater in a radial direction than in an axial direction so as to provide enlarged wedge-shaped openings between said portions, the foam structure of said packing units at said peripheral portion being relatively stronger in the axial direction and sufficiently rigid to prevent articulation between said outwardly curling portion and said central substantially cylindrical portion, the positioning of said annular portions providing wedge-shaped openings adapted to interlock with at least one of the other said individual packing units, said interlocking extending throughout the said packing mass to cooperatively prevent migration of an article packed therein, said respective curling and cylindrical annular portions presenting a shape configuration wherein outermost portions thereof are substantially equidistant from the geometric centers of said individual packing units.

Claim 8

Dependent Claim 185 words

In a method for the continuous manufacture of free flow, interlocking foamed expanded plastic packing materials of generally cylindrical cross-section, the continuous steps of heating an expandable plastic foam material to form a semisolid extrusion mass characterized by the presence of internal gas cells, extruding the heat-softened mass along an extrusion axis to form a heat-softened tube, lengthening said heat-softened tube to longitudinally stretch the gas cells therein, cooling said tube to a set stage, continuously slicing into and through said tube to form and sever individual plastic units having two outer substantially cylindrical portions substantially permanently secured to a central cylindrical portion and to one another at a peripheral portion thereof, and thereafter heating said severed plastic units to expand the longitudinally stretched gas cells in said cylindrical portions so that the central portion expands substantially radially to form a radially expanded annular core and said outer portions expand and curl in both radial and axial directions to form radially expanded outwardly curling annular portions, whereby outer edges of said annular portions are substantially equidistant from the geometric centers of the expanded packing units.

Claim 9

Dependent Claim 185 words

In a method for the continuous manufacture of free flow, interlocking foamed expanded plastic packing materials of generally cylindrical cross-section, the continuous steps of heating an expandable plastic foam material to form a semisolid extrusion mass characterized by the presence of internal gas cells, extruding the heat-softened mass along an extrusion axis to form a heat-softened tube, lengthening said heat-softened tube to longitudinally stretch the gas cells therein, cooling said tube to a set stage, continuously slicing into and through said tube to form and sever individual plastic units having two outer substantially cylindrical portions substantially permanently secured to a central cylindrical portion and to one another at a peripheral portion thereof, and thereafter heating said severed plastic units to expand the longitudinally stretched gas cells in said cylindrical portions so that the central portion expands substantially radially to form a radially expanded annular core and said outer portions expand and curl in both radial and axial directions to form radially expanded outwardly curling annular portions, whereby outer edges of said annular portions are substantially equidistant from the geometric centers of the expanded packing units.

Claim 10

Dependent Claim 31 words

A method as in claim 6 wherein said individual plastic units are severed and sliced in a simultaneous operation involving the concurrent movement of severing and slicing means through said tube.

Claim 11

Dependent Claim 31 words

A method as in claim 6 wherein said individual plastic units are severed and sliced in successive operations involving progressive and successive movement of slicing and severing means through said tube.

Claim 12

Dependent Claim 35 words

A method as in claim 8 wherein each severing operation is followed by at least two slicing operations, the time between adjacent slicing operations being greater than the time between adjacent severing and slicing operations.

Claim 13

Dependent Claim 36 words

A method as in claim 6 wherein said slicing means contact said tube in such fashion to form a longitudinal cut substantially parallel to the axis of the tube, followed by contact with said severing means.

Claim 14

Independent Claim 216 words

A method for the continuous manufacture of free flow, interlocking packing materials of low bulk density, comprising continuously feeding an extrusion mass composed of heat softenable plastic material together with foaming and nucleating agents to an extrusion zone, continuously heating said extrusion mass and extruding the same in the form of a hollow heat-softened tube, said heat-softened tube being subject to cooling in an ambient atmosphere to a set stage, continuously frictionally engaging set portions of the extruded tube to pull the same away from the extrusion zone to thereby longitudinally stretch and to maintain the freshly extruded material in a desired hollow tube configuration, such longitudinal stretching serving to longitudinally orient gas cells formed in the walls of the tube during the extruding, continuously cooling the extruded tube in an ambient atmosphere to a set stage, continuously slicing and cutting the set tube to form severed tube sections having a central hollow annular core and two adjacent substantially hollow annular tube portions, and thereafter heating the severed tube sections to expand the longitudinally oriented cells to effect a substantially radial expansion of the central core and a combined radial and axial expansion of the adjacent portions, said combined radial and axial expansion occurring as a result of outward curling expansion of said adgancet annular portions.

Claim 15

Independent Claim 216 words

A method for the continuous manufacture of free flow, interlocking packing materials of low bulk density, comprising continuously feeding an extrusion mass composed of heat softenable plastic material together with foaming and nucleating agents to an extrusion zone, continuously heating said extrusion mass and extruding the same in the form of a hollow heat-softened tube, said heat-softened tube being subject to cooling in an ambient atmosphere to a set stage, continuously frictionally engaging set portions of the extruded tube to pull the same away from the extrusion zone to thereby longitudinally stretch and to maintain the freshly extruded material in a desired hollow tube configuration, such longitudinal stretching serving to longitudinally orient gas cells formed in the walls of the tube during the extruding, continuously cooling the extruded tube in an ambient atmosphere to a set stage, continuously slicing and cutting the set tube to form severed tube sections having a central hollow annular core and two adjacent substantially hollow annular tube portions, and thereafter heating the severed tube sections to expand the longitudinally oriented cells to effect a substantially radial expansion of the central core and a combined radial and axial expansion of the adjacent portions, said combined radial and axial expansion occurring as a result of outward curling expansion of said adgancet annular portions.

Claim 16

Dependent Claim 28 words

A method as in claim 11 wherein the continuous slicing and cutting operations thereby effect internal curling of said central core upon itself, in substantially the same plane.

Claim 17

Dependent Claim 40 words

A method as in claim 11 wherein the continuous slicing and cutting operations are timed to producee a relatively thick annular central portion and relatively thin adjacent annular portions on either side thereof, to thereby facilitate said outward curling expansion.

Claim 18

Dependent Claim 55 words

A method as in claim 11 wherein initially expanded sliced tubular sections are cooled and held for a period of time sufficient to permit equalization with ambient temperatures and pressures, following which the expanded severed sections are again heated to expand the same and to thereby further enlarge the dimension of the severed tubular sections.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1978-07-28	1979-01-27	1979-07-29	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1982-07-28	1983-01-27	1983-07-29	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1986-07-28	1987-01-27	1987-07-29	$7700.00	Window Closed / Lapsed

Free flow, interlocking packing material of low bulk density

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