Metal container, and in particular container for a powder product packaged with a pressure difference between the package interior and the surrounding atmosphere.

Abstract

 A metal container consisting of a lateral wall (2) defining a hollow body, to the upper and lower end edges of which there are secured. by seam-joining, a base (4) and a lid (6) consisting of a metal annular band (8) to the inner edge of which a flexible sheet (10) is secured, extending into a tab (12) bent to face the sheet, characterised in that said lid (6) comprises at least one hole (14, 16, 18) provided in the metal annular band (8), and is maintained closed by the sheet (10) when the container is in the closed configuration and is brought into the open configuration by operating the tab (12) such as to detach the sheet (10) from the annular band (8).

Description

[0001] The present invention relates to a metal container, and in particular a container for a powder product packaged with a pressure difference between the package interior and the surrounding atmosphere.

[0002] The invention relates more specifically to an improved easily opened closure structure for a closed metal container containing a powder product such as coffee roasted and ground under pressure, the lid of which enables gas ventilation during initial opening of the package, while at the same time preventing escape of the powder product.

[0003] For some years it has been known to package ground roast coffee under pressure.

[0004] This packaging method enables the user to sense a pleasant aroma when opening the package, however it presents the drawback that the gas flow entrains the coffee powder with it from the package interior to the outside.

[0005] US 5688544 relates to a container for a powder product under vacuum which is provided with an aperture enabling aeration before opening the container.

[0006] The object of the invention is to provide a container which enables the lid opening to be correctly controlled such as to enable outflow of the internal pressure while internally retaining the powder product.

[0007] This object is attained by a metal container as described in claim 1.

[0008] A preferred embodiment and two variants of the present invention are further clarified hereinafter with reference to the accompanying drawings, in which:

Figure 1 is a section through a container according to the invention,

Figure 2 is a plan view thereof,

Figure 3 is a plan view of a first variant thereof, and

Figure 4 is a plan view of a second variant thereof.

[0009] As can be seen from the figures, the metal container according to the invention is in the form of a preferably cylindrical hollow body consisting of a lateral wall 2, to the end edges of which a base 4 and a lid 6 are secured by seam-joining.

[0010] The lid 6 consists of an annular band 8 of metal, preferably aluminium, to the inner edge of which a thin sheet 10 of flexible material, preferably plastic or metal, is secured by thermowelding.

[0011] Said sheet 10 presents at its circumferential edge a bent-over tab 12 glued to the sheet by a glue spot 20. In the embodiment shown in Figure 2, the annular band 8 comprises three small holes 14 in a position below the tab 12.

[0012] The use of the container according to the invention is traditional. The tab 12 is gripped, raised and then pulled to detach the sheet 10 from the annular sheet 8.

[0013] In this step, as soon as the tab is raised, the gas is enabled to escape through the holes 14 but without the particulate material being able to escape from the container interior.

[0014] In the embodiment shown in Figure 3, the inner perimetral edge of the annular band 8 comprises a plurality of notches 16.

[0015] Again in this case, on raising the tab and starting to detach the sheet 10 from the annular band 8, an air flow can escape through said notches 16.

[0016] In the embodiment shown in Figure 4, the thin sheet 10 comprises a small hole 18 at the glue spot 20 by which the tab 12 is secured to the sheet 10.

Claims

1. A metal container consisting of a lateral wall (2) defining a hollow body, to the upper and lower end edges of which there are secured. by seam-joining, a base (4) and a lid (6) consisting of a metal annular band (8) to the inner edge of which a flexible sheet (10) is secured, extending into a tab (12) bent to face the sheet, characterised in that said lid (6) comprises at least one hole (14, 16, 18) provided in the metal annular band (8), and is maintained closed by the sheet (10) when the container is in the closed configuration and is brought into the open configuration by operating the tab (12) such as to detach the sheet (10) from the annular band (8).

2. A metal container as claimed in claim 1, characterised in that the holes (16) are provided along the entire annular band (8).

3. A metal container as claimed in claim 1, characterised in that the holes (14) are provided in the metal annular band (8) at the zone in which the tab (12) is bent.

4. A metal container as claimed in claim 1, characterised in that the hole (18) is provided in the sheet (10) and is closed by a glue spot (20) which also secures the tab.

5. A metal container as claimed in claim 1, characterised by being of cylindrical shape.

6. A metal container as claimed in claim 1, characterised in that the sheet (10) is made of plastic material.

7. A metal container as claimed in claim 1, characterised in that the sheet (10) is made of metal material.

8. A metal container as claimed in claim 1, characterised in that the sheet (10) is secured to the annular band (8) by thermowelding.

Drawing