WO2021058998A1

WO2021058998A1 - Metal can

Info

Publication number: WO2021058998A1
Application number: PCT/IB2019/058056
Authority: WO
Inventors: Maciej KOCIOLEK
Original assignee: Can-Pack Spolka Akcyjna
Priority date: 2019-09-23
Filing date: 2019-09-23
Publication date: 2021-04-01

Abstract

A metal beverage can having a cylindrical body, a lid and a bottom section, where the body and the bottom section are formed from one piece of sheet in such a way, that the central part of the bottom section constitutes a dome curved to the inside of the can, which is surrounded by a ring embossed to the outside of the can, characterized in that, the diameter of the base of the can (D) is from od 45,80 do 48 mm, and the depth of the dome measured from the surface defined by the bottom edge of the ring to the deepest central point of the dome (Dt) is greater than 10 mm.

Description

METAL CAN

TECHNICAL FIELD

The object of the present invention is a metal beverage can having a cylindrical body, a lid and a bottom section, where the body and the bottom section are formed from one piece of sheet in such a way, that the central part of the bottom section constitutes a dome curved to the inside of the can, which is surrounded by a ring embossed to the outside of the can.

BACKGROUND ART

Two-piece beverage cans are manufactured by means of drawing and ironing usually from aluminum, but also other metals like steel may be applied. Aluminum has good stretching properties and it is possible to form it into cylindrical shape by means of drawing and to obtain thin walls by means of ironing. The base of such a can has a shape of a dome curved inside the can and is surrounded by a circumferential flange which defines the standing ring, so that the can may be placed on a flat surface.

Patent specification EP2185428 discloses a metal can consisting of a vertically oriented cylindrical sidewall and an end wall constituting unitary structure with the cylindrical sidewall; the said end wall consists of a recessed central portion and a downwardly flanged rim portion, that constitutes essentially annular standing ring, where the said downwardly flanged rim portion comprises a first outer convexly curved annular surface that in vertical cross-section has a first radius of curvature R1, a second, lower convexly curved annular surface that in vertical cross-section has a second radius of curvature R2, and a third, inner convexly curved annular surface that when viewed in vertical cross-section has a third radius of curvature R3, where the first, second and third radii of curvature R1, R2 and R3 are each different from each other, and the three convexly curved surfaces constitute compound curves.

Patent application WO2016146362 discloses a body of a beverage can. The can body is formed from a metal sheet and consists of a circumferential wall as a side wall and a can bottom which has a calotte- shaped central section which is curved inwards and a standing section which surrounds the central section in an annular manner and curves outwards. The standing section curved outward is connected to the circumferential wall by means of an outer transition section extending aslant in the cross-section and defines a standing ring, along which the standing section at least approximately touches a flat surface when the can body is placed on such a flat surface. The geometry of the bottom is defined by three partial radii R3a, R3b and R3c, which describe the geometry of a standing ring as part of the standing section curved outwards and have the following dimensions: 0.8 < R3a < 1.2 mm, 1.2 < R3b < 1.6 mm, and 2.0 < R3a < 3.0 mm.

DISCLOSURE OF THE INVENTION

A metal beverage can having a cylindrical body, a lid and a bottom section, where the body and the bottom section are formed from one piece of sheet in such a way, that the central part of the bottom section constitutes a dome curved to the inside of the can, which is surrounded by a ring embossed to the outside of the can, characterized in that, the diameter of the base of the can is from od 45,80 do 48 mm, and the depth of the dome measured from the surface defined by the bottom edge of the ring to the deepest central point of the dome is greater than 10 mm.

Preferably the depth of the dome is from 10.80 to 11.80 mm.

Preferably the depth of the dome is from 11.90 to 12.50 mm.

The height of the outer wall of the bottom ring measured from the surface defined by the bottom edge of the ring to the place where the wall of the ring turns into outer surface of the bottom section is greater than 3.5 mm, preferably 4 mm.

The radius (R1) of the curvature of the dome surface in the place, where the dome connects with the wall of the ring, is from 1.9 to 3.6 mm. The radius (R2) of the curvature of the dome surface between its central part, and the part of the connection with the wall of the ring is from 9 to 30 mm, preferably 9.1 to 29.5 mm.

The radius (R3) of the curvature of the central part of the dome is from 39 to 42 mm, preferably 39 to 41.5 mm.

The diameter of the base of the can (D) is from 46.50 to 47.37 mm.

The object of the invention is disclosed at the drawings.

EXAMPLE

A metal beverage can has a cylindrical body (partly visible), a lid (not visible at the drawing) and a bottom section. The body and the bottom are formed from one piece of sheet. The central part of the bottom section constitutes a dome curved to the inside of the can, which is surrounded by a ring embossed to the outside of the can. The diameter of the base of the can (D) is 47,37 mm, and the depth of the dome measured from the surface defined by the bottom edge of the ring to the deepest central point of the dome (Dt) is from 10.80 to 11.80 mm or from 11.90 to 12.50 mm. (Dt1 is 10.812 mm, and Dt2 is 12.149 mm). The height of the outer wall of the bottom ring measured from the surface defined by the bottom edge of the ring to the place where the wall of the ring turns into outer surface of the bottom section H is 2.05 mm. The radius (R1) of the curvature of the dome surface in the place, where the dome connects with the wall of the ring, is from 1.9 to 3.6 mm. The radius (R2) of the curvature of the dome surface between its central part, and the part of the connection with the wall of the ring is from 9 to 29.5 mm. The radius (R3) of the curvature of the central part of the dome is from 39 to 41.5 mm.

The tests were carried out with the cans having dimentions like in the table.

It was found out that owing to the modification of the bottom section profile in relation to the existing state of the art it was possible to increase the resistance of the can to the pressure inside the can. As a result the cans may be stored for a longer time in increased temperature. The said modification is particularly important in case of the beverages manufactured for markets in tropical countries.

Claims

PATENT CLAIMS

1. A metal beverage can having a cylindrical body, a lid and a bottom section, where the body and the bottom section are formed from one piece of sheet in such a way, that the central part of the bottom section constitutes a dome curved to the inside of the can, which is surrounded by a ring embossed to the outside of the can, characterized in that, the diameter of the base of the can (D) is from od 45,80 do 48 mm, and the depth of the dome measured from the surface defined by the bottom edge of the ring to the deepest central point of the dome (Dt) is greater than 10 mm.

2. The can according to claim 1, characterized in that, the depth of the dome is from 10,80 to 11,80 mm.

3. The can according to claim 1, characterized in that, the depth of the dome is from 11,80 to 12,50 mm.

4. The can according to claim 1 or 2 or 3, characterized in that, the height of the outer wall of the bottom ring measured from the surface defined by the bottom edge of the ring to the place where the wall of the ring turns into outer surface of the bottom (H) is greater than 3.5 mm, preferably 4 mm.

5. The can according to any of the preceding claims, characterized in that, the radius (R1) of the curvature of the dome surface in the place, where the dome connects with the wall of the ring, is from 1.9 to 3.6 mm.

6. The can according to any of the preceding claims, characterized in that, the radius (R2) of the curvature of the dome surface between its central part, and the part of the connection with the wall of the ring is from 9 to 30 mm, preferably 9.1 to 29.5 mm.

7. The can according to any of the preceding claims, characterized in that, the radius (R3) of the curvature of the central part of the dome is from 39 to 42 mm, preferably 39 to 41.5 mm.

8. The can according to any of the preceding claims, characterized in that, diameter of the base of the can (D) is from 46.50 to 47.37 mm.