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BR-122023013802-B1 - METHOD FOR FORMING A STACKABLE METAL CUP

BR122023013802B1BR 122023013802 B1BR122023013802 B1BR 122023013802B1BR-122023013802-B1

Abstract

The present invention relates to a metal cup and a method for forming it. The metal cups of the present invention comprise a plurality of straight-walled, thin sections with a tapered profile. A concave part is provided at the bottom of the cup. The cup may comprise a disposable cup, a reusable cup, or a recyclable cup.

Inventors

  • ANTHONY J. SCOTT

Assignees

  • BALL CORPORATION

Dates

Publication Date
20260310
Application Date
20191206
Priority Date
20181210

Claims (6)

  1. 1. Method for forming a stackable metal cup (20), comprising: providing (50) a material to be worked; cutting a metal blank from the material to be worked; forming (52) at least one cup (20) from the metal blank using a drawing and stretching operation; performing a secondary stretching operation (54) on the cup to give the cup a predetermined height (H2) and wall thickness; after the secondary stretching operation (54), trimming (58) the cup (20) to a second height (H2); corrugating (60) the top edge of the trimmed cup to form a rim; forming one or more straight-walled sections (10) in the cup (20) by stretching (62) it; expanding (64) each of the one or more straight-walled sections (10) using one or more dies with a tapered profile; forming (66) a concavity (24) at the bottom of the cup (20); characterized in that the method further comprises forming a stacking feature at the bottom of the cup (20) providing a compressive force at the bottom of the cup (20), such that a lower section of the cup (20) comprises a taper or inward inclination.
  2. 2. Method according to claim 1, characterized in that the material to be worked comprises an aluminum coil (104), and the step of forming at least one cup comprises subjecting at least a part of the aluminum coil (104) to the drawing and stretching operation.
  3. 3. Method according to claim 1, characterized in that it further comprises a step of providing (72) a coating on at least one inner part of the cup (20).
  4. 4. Method according to claim 1, characterized in that it further comprises decorating or coating (70) at least one of an inner and one outer surface of the metal cup (20).
  5. 5. Method according to claim 1, characterized in that the step of curling (60) the top edge occurs before the step of forming (62) one or more straight wall sections (10).
  6. 6. Method according to claim 1, characterized in that the material to be worked comprises a pre-coated aluminum sheet, thereby reducing the need for additional washing and coating steps in cup formation (20).

Description

[001] This patent application claims priority to and benefit of U.S. Provisional Patent Application No. 16/214,477, which is a partial continuation thereof, and claims the benefit of U.S. Provisional Patent Application No. 15/811,032, filed on November 13, 2017, and claims the benefit of U.S. Provisional Patent Application No. 62/455,697, filed on February 7, 2017, the descriptions of which are incorporated herein by reference in their entirety. FIELD [002] The present invention relates generally to metal cups and methods of forming them. More specifically, the present invention relates to beverage cups formed from a metal. Various embodiments of the present invention provide a thin-walled beverage cup that is stackable with cups of similar construction. BACKGROUND [003] Beverage cups and beverage containers typically comprise a plastic material. Plastic cups are manufactured by injection molding or thermoforming operations, which can form lightweight, disposable cups. Existing metal beverage containers comprise beverage cans, including an end closure attached to the top end of a filled can. [004] U.S. Patent 4,366,696 to Durgin et al., which is hereby incorporated by reference in its entirety, describes a snap-fit can and the method of forming the same from a metal blank. Durgin et al., however, fail to describe the various features of the present invention, including, for example, a tapered or stepped geometry, as shown and described in this descriptive report, and the methods of forming the same. [005] U.S. Patent 4,914,937 to Bulso et al., which is hereby incorporated by reference in its entirety, describes a method for forming a tapered vessel. Bulso et al. provide a straight-walled cup and a method for forming it, but it lacks several teachings of the present invention. [006] U.S. Patent 6,463,776 to Enoki et al., which is hereby incorporated by reference in its entirety, describes a method of manufacturing bottle-shaped cans with a neck and shoulder portion. Enoki et al. fail to describe several features and methods of the present invention. For example, Enoki et al. fail to provide a cup-shaped container with tapered, straight side walls. SUMMARY [007] Consequently, there is a long-standing and unmet need to provide a metal cup that is reusable and recyclable. There is also a need to provide a tapered metal cup that is stackable to improve the transport and storage of a plurality of cups. [008] In various embodiments, a tapered metal cup is provided, comprising shallow wall angles. The shallow wall angles, at least as used in this descriptive report, comprise wall angles that are less than 10 degrees, measured from a vertical centerline or vertical axis of the cup. The angled sides and shallow wall angles of the cups, as shown and described in this descriptive report, provide the ability to stack at least two cups, which provides advantages for transport and storage. [009] In various embodiments, the metal cups are provided comprising thin-walled aluminum. Preferably, the metal cups are provided comprising a recycled aluminum alloy. Various embodiments, including those comprising thin-walled aluminum, provide cups that are lightweight, are formed from a recycled and/or recyclable material, and are, for example, more rigid, useful, and durable than conventional plastic cups. [0010] In preferred embodiments, a metal cup is provided with a constant wall thickness along at least part of the cup. An inlet gauge of the cup is reduced to a thinner wall thickness in the side walls of the cup. Steps or ribs extending horizontally preferably extend throughout a circumference of the cup, and are provided to incorporate mechanical strength into the finished cup while maintaining a lightweight characteristic for the cup. The steps or ribs are provided as transition points between sections of the finished cup having different diameters. Alternatively, a tapered cup is provided without ribs, wherein the cup comprises a relatively smooth and linear side wall, extending from the upper end of the tapered cup to the closed lower end. [0011] In several embodiments, a method for forming a metal cup is provided. In one embodiment, a method for forming a metal cup comprises feeding an aluminum coil into a deep drawing press and producing a straight-walled cup from a substantially circular metal blank cut from the aluminum coil. The cup preferably has a constant wall thickness, which is approximately equal to the aluminum input gauge. The cup is then fed into a body production device, in which the metal is smoothed. The cup is further formed by washing it and by decorating and/or coating an external and an internal part thereof. In certain embodiments, at least part of the external part of the cup is decorated with a color, a logo, or other visual information. After the washing and coating operations, a top edge of the cup is corrugated, partially corrugated, or strangulated to eliminate the sharp edge that is formed by th