Claims
- 1. A method of manufacturing a disposable cup, comprising:cutting a blank shaped to provide a substantially truncated conical body having an integral lid portion extending upwardly from an upper edge of said body and having first and second intersections with said upper edge at opposite sides of said lid portion; providing said blank with a curved score line beneath said lid portion, defining a boundary between said lid portion and said body, extending from said first intersection of said lid portion with said upper edge, curving downwardly therefrom, and thence back upwardly to said second intersection of said lid portion with said upper edge, such that said lid portion is foldable along said curved score line towards an opposite side of said upper edge when said cup is assembled; and forming said blank into a cup by joining opposing lateral side edges and securing a bottom to said blank, said blank being more particularly shaped specifically such that when formed into a cup, said lid portion is movable between a raised position and a closed position, such that in said closed position said lid portion conforms generally to an opposite wall of said cup and has a distal edge with an opening allowing passage of cup contents, and such that in moving said lid portion from said raised position to said closed position, said lid inverts to a concave configuration, said concave configuration tending to resist moving said lid portion towards said raised position; and further providing the step, before forming said blank into a cup, of providing said blank with generally axial score lines spaced slightly from said intersections and extending from said curved score line to an upper edge of said lid portion, thereby defining, with said upper edge and said curved score line, small generally triangular portions, such that when said cup is formed and said lid inverts to a concave configuration, said small generally triangular portions flip to a position where they are downwardly angled towards said lid portion, thereby further tending to resist moving said lid portion towards said raised position.
- 2. A method as recited in claim 1, wherein said curved and axial score lines are provided at generally the same time as the blank is cut.
- 3. A method as recited in claim 1, wherein said cutting of said blank is carried out such that said lid portion has a larger cross-dimension than the cross-dimension of said body in the closed position of said lid portion, so that, when said lid portion is pushed into said body, said lid is bent into a downward parabolic shape to seal cup content access along an inside of said cup, said lid then being partly held in said cup in said closed position by frictional forces between said lid and said inside of said cup, and partly by said generally triangular portions, thereby increasing the force holding said lid in said closed position and resisting movement of said lid away from said closed position.
- 4. A method as recited in claim 3, wherein said cutting of said blank is carried out such that said lid portion is movable between said raised position and said closed position via a semi-dosed position which the lid reaches after being pressed from said raised position, and wherein said lid external dimension is substantially larger than the internal dimension of said cup in an area adjacent said closed position of said lid, necessitating the lid to be further pressed towards said closed position to overcome frictional forces between said lid free edge and said inside of said cup, causing said cup body to assume an ovate cross-section shape.
- 5. A method as recited in claim 1, wherein said upper edge is provided with inwardly projecting portions to act as locking edges which catch said free edge of said lid, when said lid is in said closed position, to lock said lid in said closed position.
- 6. A method as recited in claim 5, wherein said locking edges are arranged adjacent said axial score lines.
- 7. A method as recited in claim 1, wherein a ratio of a horizontal line between said intersections, to a vertical distance from a center of said horizontal line to a lowest point of said arc of said curved score line, is approximately 3.5 to 5.5.
- 8. A method as recited in claim 1, wherein said blank is shaped such that said lid portion is adjacent a lateral edge thereof, so that a cup body joint line is on a side of said cup, thereby allowing unencumbered placement of lettering on a front of said cup, a back of said cup and on said lid.
REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of application Ser. No. 09/588,284, filed Jun. 7, 2000, which claims benefit of 60/137,703 filed Jun. 7, 1999.
US Referenced Citations (17)
Provisional Applications (1)
|
Number |
Date |
Country |
|
60/137703 |
Jun 1999 |
US |
Continuations (1)
|
Number |
Date |
Country |
Parent |
09/588284 |
Jun 2000 |
US |
Child |
09/755140 |
|
US |