The present invention relates generally to beverage cans and more particularly to the size of drinking aperture that is created in a beverage can end. There is increasing pressure by consumers to increase the size of such drinking apertures to increase the pleasure of drinking the beverage contained within the can, directly from the can.
Conventional full aperture can ends include a score that extends around a major portion of the end's centre panel and defines a removable panel. A tab is attached to the removable panel by a rivet. The tab has a tail or handle end on one side of the rivet and a nose end on the opposite side of the rivet and the tab is positioned so that it's nose end lies adjacent to or touching the score. To open the can end, a user lifts the tail or handle end of the tab, which causes the tab to pivot about the rivet and presses the nose end adjacent to the score, propagating fracture of the score until the removable panel is detached from the remainder of the end. Typically, full aperture ends are attached to food can bodies by conventional seaming techniques.
Full aperture food can ends are designed primarily to allow full product release of the foodstuff contained within the food can. Often, this foodstuff is packed under slight negative pressure. However, where pressurised food cans are proposed having positive internal pressure, the internal pressures are relatively low and merely determined by the internal pressure required to maintain the structural rigidity of the food can, which is often relatively “thin-walled”.
In conventional beverage cans the beverage product, such as carbonated soft drinks or beer, typically is held under much higher pressures than the internal pressures in food cans, resulting in concerns related to “blow-off” of the ends upon initial opening by a user or when subjected to adverse handling. For these reasons, the conventional beverage can has an end defining a restricted aperture, which can be safely opened by a consumer.
U.S. Pat. No. 5,711,448 A (REYNOLDS METALS CO) 27.01.1998 describes a conventional “large opening end” (that is an end having a relatively large opening), as currently used on some beverage cans. This patent describes a “standard size opening” of about 322.58 square mm (0.5 square inches) and a “larger opening” of about 322.58-483.87 square mm (0.5 to 0.75 square inches), which represents a relatively small fraction of the area of the centre panel.
Full aperture beverage can ends have been sold in the past but these had serious safety issues and have now been withdrawn from the market. ‘Spiral scored’ ends were produced for Sapporo beer, where the can end was vented in its centre and then the score propagated to the edge of the can end panel and then around the periphery thereof. Venting was critical because the end was relatively large, 66 mm diameter with a 52 mm centre panel size. If the end was opened without being vented the panel would explode and missile towards the consumer. Thus a vent was used to provide safe venting and release the internal pressure in the can before opening. However the resulting spiral geometry of the opened end panel was very dangerous having several long exposed cut edges and for this reason, this can end configuration was withdrawn.
Conventional beverage cans are often banned from being sold at festivals and events, because the restricted aperture prevents the contents of the can being from being discharged quickly if an opened beverage can is thrown. Thus, even if a conventional beverage can is opened at the point of sale at a festival or event, it may still provide a dangerous missile if thrown.
Accordingly, the present invention provides a full aperture beverage end having a centre panel, a countersink surrounding the centre panel, a main score arranged in proximity to the countersink to define a removable aperture panel and a vent score, characterised in that the beverage end is adapted for use with products held under pressure exceeding 207 kPa (30 psi) when opened and during opening the vent score is adapted to sever first, controlling the pressure differential between the external surface and internal surface of the centre panel. In this way, the pressure differential between the external surface and the internal surface of the centre panel reaches equilibrium gently. This allows the main score to tear in a controlled and reliable manner. The can may also be rated for internal pressures of at least 483 kPa (70 psi), 586 kPa (85 psi), or 621 kPa (90 psi).
Additionally, the main score may have an outer wall proximate the drinking lip of the end (once the aperture panel is removed), an inner wall proximate the aperture panel and a land at the base of the main score. The land has a thickness that is smaller proximate the main score outer wall than the land thickness proximate the main score inner wall. This configuration ensures that the land remains affixed to the aperture panel after the aperture panel is removed.
Preferably, the centreline of the main score is located between 0.000 and 0.508 mm (0.020 inches), more preferably between 0.000 and 0.254 mm (0.010 inches), more preferably between 0.000 and 0.152 mm (0.006 inches), more preferably between 0.000 and 0.102 mm (0.004 inches), and most preferably between 0.000 and 0.051 mm (0.002 inches) from a centre of a transition radius between the countersink and the centre panel.
A nose of the tab in its rest state is radially inwardly spaced apart from an inner edge of the main score by between 0.000 and 0.203 mm (0.008 inches), more preferably between 0.000 and 0.127 mm (0.005 inches), measured horizontally. In its partially actuated state, in which the tab nose contacts the centre panel, the nose of the tab is approximately between the centreline of the main score and 0.127 mm (0.005 inches) radially inboard from an inner edge of the main score—more preferably within 0.051 mm (0.002 inches) of an inner edge of the main score. Among the benefits for consumers are that after opening, the beverage can becomes more like a drinking glass. Consumers can drink from the can from any orientation and the can contents can be sipped rather than poured into the mouth. Furthermore, the contents of the can is visible after opening, showing the colour, level of carbonation, and head (with widgeted beers).
One of the benefits for fillers is that the cans may be sold at festivals and events, as they can no longer be used as missiles. The larger, full aperture ensures that once opened, the majority of the beverage does not remain in the can if it is thrown. Furthermore, sealed beverage cans are preferable to glasses as they can be freshly opened immediately upon serving and thus many drinks can be freshly served in the interval periods during events.
The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
A beverage can 10 includes a can body 12 and a can end 14 that are joined together at a seam 16. Preferably, can body 12 and seam 16 are conventional according to commercial carbonated beverage standards.
Countersink 22 extends from the lower part of wall 20 and includes a curved bottom portion 24 and an inner wall 26 that extends up from bottom portion 24. Inner wall 26 has a straight portion that merges into centre panel 30 via transition 28 having a radius R. The origin of radius R is point C, as best shown in
Centre panel 30 includes a rivet 34, a moustache score 46, a main score 50, and an anti-fracture score 52. Rivet 34 is preferably conventional. A tab 36 is attached to centre panel 30 by rivet 34. Tab 36 is preferably a solid tab—that is, without an integral hinge. Centre panel 30 is preferably substantially planar in its unseamed or unpressurized state.
Moustache score 46 is configured to enable venting of the pressurized, filled can 10. For internal pressures greater than 207 kPa (30 psi), the vent score described in the applicant's co-pending patent application no. U.S. Pat. No. 12/796,972 is preferred. As tab 36 is lifted by its handle or heel 38, moustache score 46 is designed to break before main score 50 to vent the internal pressure in filled can 10.
Main score 50 extends about the periphery of centre panel 30 and defines a removable aperture panel 54. As shown in
The inventors have identified the importance of configuring the can end 14 in such a way that main score 50 is in a location on the can end 14 that is sufficiently stiff to promote initial rupture of score 50 upon actuation of tab 36.
Preferably, the centreline of main score 50 is near the countersink 22 at the point where the tab nose 40 contacts the centre panel 30, such that the structural stiffness of countersink 22 prevents excessive panel deflection to promote initial score fracture. For example, the horizontal distance between transition curve origin C and the vertical centre of the main score 50 may be as low as 0.000 inches (i.e. falling on the same vertical axis). Preferably, the centreline of main score 50 does not extend radially outside point C so that the main score does not interfere with the structural performance of countersink 22. In the embodiment of
Alternatively, main score 50 may be spaced apart from the countersink 22, but is preferably located near a structural stiffener, such as an emboss, deboss, or like ridge. The configuration and distance of the main score and countersink may be chosen according to parameters that will be understood by persons familiar with beverage can end engineering and design upon considering this specification.
Thicknesses Ta and Tb may be chosen according to the desired parameters of can end 14, such as proximity of main score 5 to the countersink 22, thickness and material of the can end, desired pressure rating, tab configuration, and the like. For the embodiment shown in
The score residual at thinner end 56x of score land 56 tends to fracture more readily than that at thicker end 56y. This tendency is an advantage in controlling the location of the fracture within main score 50. In this regard, the cross sectional structure of score 50 is configured such that the score residual of land 130c remains attached to aperture panel 54 rather than to lip 32 (that is, because the score residual at land outer end 56x is thinner than that at land inner end 56y), therefore leaving lip 32 having a smoother configuration.
Also, the inventors have found that for a given score, the structure and operation of the tab affects the reliability and predictability of the main score fracture. In this regard, if tab nose 40 is too far from main score 50, end 14 may fracture between the main score 50 and the anti-fracture score 52 or within anti-fracture score 52, rather than solely in the main score 50. Measured upon actuation of tab 36, when the tab nose 40 first contacts can end 14 (before main score fracture), tab nose 40 preferably does not span across main score 50 to touch the outer score wall 51x. Preferably, tab nose 40, upon contact with can end 14, is at the centreline of main score 50 or on the aperture panel 54, within 0.127 mm (0.005 inches) radially inboard of the inner edge 60 of main score 50 (see
A user may also measure the location of tab nose 40 with the tab in its at-rest state before actuation. In this regard, tab nose 40 preferably is between 0.000 and 0.203 mm (0.008 inches) from the inner edge 60 of main score 50, and more preferably between 0.000 and 0.127 mm (0.005 inches), as measured radially inwardly from edge 60. The difference in location of tab nose 40 relative to main score 50 between its initial contact state and its at-rest state is due to shunting during the tab actuation process. Tab 36 shunts forward in the end shown in
The location of the tab nose 40 relative to the main score 50 may be chosen according to the design parameters of the particular can end, for example main score configuration, tab design, vent score design, internal pressure, and other factors that will be understood by persons familiar with can end engineering and design upon considering the present specification.
As illustrated in
Once the main score 50 has completely severed the resulting aperture panel 54 can be discarded and a user can drink directly from aperture 58.
Each of ends 14a, 14, 14c, and 14d are seamed onto a can body 12a, 12b, 12c, 12d.
End 14a of
End 14b of
End 14d of
Number | Date | Country | Kind |
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09169559.3 | Sep 2009 | EP | regional |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP10/62877 | 9/2/2010 | WO | 00 | 5/17/2012 |
Number | Date | Country | |
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Parent | 12797171 | Jun 2010 | US |
Child | 13393974 | US |