WO2024209289A1

WO2024209289A1 - Crown cap closure

Info

Publication number: WO2024209289A1
Application number: PCT/IB2024/052327
Authority: WO
Inventors: Stefano Bergami; Marco Mirri
Original assignee: Sacmi Cooperativa Meccanici Imola Societa' Cooperativa
Priority date: 2023-04-03
Filing date: 2024-03-11
Publication date: 2024-10-10
Also published as: IT202300006531A1

Abstract

A shell (1) for crown closure is disclosed, said shell comprising a side wall (3) corrugated with a number N of protrusions (5) alternating with a number N of recesses (6) along a circumferential direction, each recess ending in a lower end point, the lower end points defining a reference plane (E), each protrusion ending in a peripheral end point (A), on each protrusion an intermediate point (B) being defined at an axial distance from the respective peripheral end point, said axial distance being equal to 1 millimeter measured in a direction orthogonal to said reference plane, a segment (AB) defined by said peripheral end point and said intermediate point forming an acute angle greater than 45° with a plane parallel to said reference plane.

Description

CROWN CAP CLOSURE

Background of the invention

[0001] The invention relates to a shell for crown closure, in particular for making, in general with the addition of a washer, a hermetic crown closure usable for sealing a mouth of a container like, for example, a bottle, containing pressurized liquids such as, for example, carbonated beverages.

[0002] Specifically, but not exclusively, the invention relates to a shell of a crown closure molded from a metal sheet and provided with a corrugated side wall, in which the closure is applied to an upper mouth of a container by a capping device that crushes the corrugated side wall in a radial direction towards the neck of the container, to make an undercut coupling that prevents the crown closure from detaching from the neck.

[0003] Patent publications US 2018/0370692 Al, US 2010/0326949 Al, US 2005/0199576 Al, US 2005/0029218 Al, US 2001/0035390 Al, US 6,164,472, US 5,458,253 and US 3,229,842 show some examples of crown closures usable for sealing the upper mouth of a container.

[0004] Patent publication WO 2009/100440 A2 shows a shell for crown closure according to the preamble of the first claim.

[0005] Various aspects of the prior-art shells of crown closures are improvable. Firstly, it is desirable to make a shell that although it has been molded from a sheet of relatively thin metal is still able to withstand relatively high pressure inside the container. Further, it would be desirable to provide a shell with high flexibility features to facilitate capping operations and at the same time resistance, to keep the container hermetically sealed. There would also be a need to reduce the amount of material with which the crown cap is manufactured without compromising the features thereof, in particular ensuring the hermetic seal of the closure, the facility of capping the crown cap and the precision of the dimensional regularity of the corrugations.

Summary of the invention

[0006] One object of the invention is to make a shell that is able to overcome one or more of the aforesaid limits and drawbacks of the prior art.

[0007] One object of the invention is to provide a shell for crown closure that is an alternative to those of the prior art.

[0008] One advantage is to provide a shell that enables a crown closure to be constructed that is provided with an effective hermetic seal, together with capping that is facilitated by the relatively high flexibility of the side wall of the shell, also with a side wall of relatively reduced height.

[0009] One advantage is to propose a crown shell that is moldable with great precision of the dimensional regularity of the corrugations.

[0010] One advantage is to obtain a shell by drawing from a relatively thin sheet of metal.

[0011] One advantage is to make a shell for suitable crown closure for closing a container with a pressurized gas and which is able to withstand relatively high pressure inside the container.

[0012] One advantage is to make available a relatively flexible crown shell so as to facilitate capping operations.

[0013] One advantage is to provide a shell with relatively high resistance to maintain the container hermetically sealed.

[0014] In one embodiment, a shell for crown closure comprises a corrugated side wall with a number N of corrugations defined by protrusions alternating with recesses in a circumferential direction, in which the number N of corrugations is odd and less than 19, in which each recess ends in a lower end point (on an edge of an inner side of the shell) and the lower end points define a reference plane (in particular, a support plane of the shell), in which each protrusion ends in a peripheral end point (on an edge of an outer side of the shell) and on each protrusion an intermediate point is defined at an axial distance from the respective peripheral end point, in which the axial distance is equal to 1 millimeter and is measured in a direction orthogonal to the reference plane, in which a segment defined by the peripheral end point and by the intermediate point forms, with a plane parallel to said reference plane, an acute angle greater than 45°.

[0015] It has been found that the aforesaid conformation of the protrusions of the crown shell, in particular the aforesaid inclination between two points on the ridge of a protrusion, improves the performance of the closure obtained from the shell, in particular by facilitating the capping operations and ensuring the hermetic seal of the closure.

[0016] It has also been found that a relatively low number N of corrugations (odd and less than 19, for example 15 or 17), in combination with the aforesaid conformation of the protrusions of the crown shell, with the same thickness of the metal sheet (in addition to the same hardness of the metal of the sheet), enables consumption of material to be reduced whilst obtaining a shell with suitable height and diameter, it being known that the height and diameter of the shell are parameters that are functional to the achievement of the desired performance of the closure cap. In particular, using a number of corrugations (or teeth) equal to 17 or, still better, to 15, enables a certain amount of material to be saved, so that it has been possible to reduce the shearing diameter as the saved material exceeds needs.

[0017] One advantage of the shell in question is the possibility of obtaining corrugations of significant quality (above all with great dimensional regularity) by moulding of a particularly thin and hardened metal sheet.

Brief description of the drawings

[0018] The invention can be better understood and implemented with reference to the attached drawings that illustrate one embodiment thereof by way of non-limiting example, in which:

Figure 1 is a top view of one embodiment of a shell for crown closure made in accordance with the present invention;

Figure 2 is the section executed according to the vertical section plane II of Figure 1 at a recess of the shell;

Figure 3 is the section executed according to the vertical section plane III of Figure 1 at a protrusion of the shell;

Figure 4 shows an enlarged detail of Figure 2.

Detailed description

[0019] With reference to the aforementioned figures, with 1, a crown shell has been indicated overall that is suitable for manufacturing a crown closure for closing a container. The crown closure obtained from the shell 1 is intended, in use, to be applied to an upper mouth of a container by a capping device that crushes a corrugated side wall of the shell in a radial direction towards the neck of the container, to make an undercut coupling that prevents the crown closure from detaching from the neck.

[0020] The crown shell 1 may, in particular, consist of a metal sheet with a thickness of less than 0.17 millimeters. The thickness of the metal sheet may be, in particular, less than 0.16 millimeters. The thickness of the metal sheet may be, in particular, less than 0.15 millimeters. The thickness of the metal sheet may be, in particular, equal to 0.15 ± 0.1 millimeters or equal to 0.14 ± 0.1 millimeters.

[0021] The crown shell 1 comprises an outer surface and an inner surface, where “outer” and “inner” refer to the inner cavity defined by a concave shape of the shell, so that the inner surface corresponds to the side of the shell facing inside the cavity (inner side) and the outer surface corresponds to the opposite side (outer side).

[0022] The crown shell 1 comprises a closing upper wall 2 configured to close an upper mouth of a container neck (not shown).

[0023] The crown shell 1 comprises a corrugated side wall 3 configured to be folded and to engage with an annular undercut arranged on the neck of the container.

[0024] The closing upper wall 2 may be, in particular, upwardly convex, where “upwardly” refers to a position in which the corrugated side wall 3 is placed below the closing upper wall 2 (for example when the shell 1 is on a horizontal resting plane resting with the corrugated side wall 3).

[0025] The closing upper wall 2 may comprise, in particular, a top point. The shell axis X may, in particular, pass through the aforesaid top point. The shell axis X may be, in particular, orthogonal to the top point.

[0026] The crown shell 1 comprises an annular connection wall 4 which connects the corrugated side wall 3 to the closing upper wall 2.

[0027] The corrugated side wall 3 comprises a number N of corrugations defined by a succession of N protrusions 5 and N recesses 6 alternating with each other and distributed in a circumferential direction around a shell axis X. The number N of corrugations may be, in particular, uneven and less than 19 or less than 17. The number N of corrugations may be, in particular (as in this specific embodiment), equal to 15.

[0028] Each recess 6 comprises a bottom, considering a section taken at the deepest zone of the recess (for example, section II of Figures 2 and 4), that is arranged on an inner surface (or inner side) of the shell 1 and extends along a continuous line Q (see Figure 4).

[0029] The continuous line Q may be, in particular, arranged on a plane (a meridian plane) passing through the shell axis X and orthogonal to the reference plane E.

[0030] The bottom of each recess 6 ends below in a lower end point C, i.e. in the lowest point of the bottom, which is also the lowest point of the recess 6.

[0031] The lower end points C of the various recesses 6 (or of at least three of the N recesses 6) define a lower end reference plane E. This reference plane E may correspond, in practice, to a horizontal resting plane on which the shell 1 can rest with the side wall 3.

[0032] The lower end points C, which define the reference plane E, may be, in particular, arranged circumferentially around the shell axis X.

[0033] Each protrusion 5 comprises a ridge, considering a section taken at the highest zone of the protrusion 5 (for example, section III of Figure 3), that is arranged on an outer surface (or outer side) of the shell 1 and extends along a continuous line Z.

[0034] The continuous line Z may be, in particular, arranged on a plane (a meridian plane) passing through the shell axis X and orthogonal to the reference plane E.

[0035] Each ridge ends below and peripherally in a peripheral end point A, i.e. in the point arranged outside the protrusion 5.

[0036] On each ridge, it is possible to define an intermediate point B located at a given axial distance H from the respective peripheral end point A of the ridge of the protrusion 5.

[0037] The axial distance H is measured in a direction orthogonal to the reference plane E (that may be a direction substantially parallel to the shell axis X, i.e. the shell axis X may be substantially orthogonal to the reference plane E).

[0038] By joining the peripheral end point A to the intermediate point B, a segment AB is obtained. This segment AB is inclined by an acute angle A with respect to the reference plane E, or with respect to plane G parallel to the reference plane E (the plane G, in particular, passing through point B).

[0039] The aforesaid axial distance H is equal to 1 millimeter.

[0040] The aforesaid acute angle A is greater than 45°. It has been found experimentally that an acute angle A greater than 45° enables the performance of the crown closure obtained from the shell 1 to be improved, in particular in relation to simultaneous obtaining of great closure flexibility and closure resistance. It is possible to obtain high performance even with an angle A greater than 46.5°, or with an angle A greater than 48°. The angle A may be, in particular, comprised between 45° and 55°. In the specific example, the angle A is roughly equal to 50° for all the N protrusions 5 of the shell 1.

[0041] It is observed that the segment AB and the angle A have been indicated in Figure 4 even if the plane of Figure 4 (i.e. the plane of section II at the greatest depth of a recess 6) does not correspond to the lying plane of segment AB (i.e. the plane of section III at the greater height of an adjacent protrusion 5). However, it is deemed that the used indication is convenient and clear to the reader.

[0042] The lower end reference plane E (or resting plane) may be, in particular, arranged at a distance K from the peripheral end point A located at the end of the ridge of at least one protrusion 5. The distance K may be, in particular, smaller than 1.0 mm millimeters, or less than 0.9 millimeters.

[0043] The peripheral end points A of the ridges of the protrusions 5 may be, in particular, arranged on the same plane V parallel to the reference plane E and arranged at the distance K from the reference plane E.

[0044] A plane W is considered that is orthogonal to the segment AB and passes through the point B, or a plane W orthogonal to the segment AB and passes through a point of the continuous line Z located at a distance from point B of less than 0.1 millimeters, or less than 0.2 millimeters. In practice, plane W may be defined as a plane that is orthogonal to the segment AB and passes around point B.

[0045] A point D of intersection is considered between the plane W and the continuous line Q, i.e. the continuous line arranged on the bottom of a recess 6. The point D will then be arranged on the inner surface (or inner side of the shell 1 and at the meridian section in the deepest zone of the recess 6.

[0046] The segment CD defined by points C and D, as defined above, will have a given inclination, i.e. forming a given acute angle with the reference plane E. This acute angle between the segment CD and the reference plane E is

[0047] A straight-line J is considered that is coplanar with the continuous line Q (i.e. lying on the plane of section II i.e. on the plane of Figure 4) and tangent to the continuous line Q in point D.

[0048] An angle 0 is considered between the straight-line J and the lower end reference plane E.

[0049] The crown shell 1 may be, in particular, so conformed that the angle 0 is equal to the angle A, or such that the angle 0 is substantially or almost equal to the angle A, for example the angle 0 may be included in an interval A ± 1°, or in an interval A ± 3°, or in an interval A ± 5°.

[0050] Substantially, the straight-line J is orthogonal to the plane W or almost orthogonal to the plane W.

[0051] It has been found that even this conformation of the recess 6 contributes to improving the performance of the shell, as this enables the deformability of the shell during the capping step to be facilitated and a crown closure to be obtained with effective hermetic closure of the container also over the long term.

[0052] For at least one protrusion 5, or for more than one protrusion 5, or for each of the N protrusions 5, the peripheral end point A may be, in particular, located at a radial distance R from the shell axis X. The value of the radial distance R may be, in particular, such that the corresponding value of the diameter D = 2R is included in a range D = 32.10 ± 0.2 millimeters.

[0053] The radial distance R may be, in particular, such that the corresponding value of the diameter D = 2R is included in the aforesaid interval for each of the N protrusions. In particular, the aforesaid radial distance R and the corresponding value of the diameter D = 2R may be equal for all the N protrusions.

[0054] In particular, it is possible to define a diameter D equal to a minimum diameter circumscribed between the so-called tips of the crown, i.e. the various peripheral end points A of the protrusions 5, in which the minimum circumscribed diameter D is comprised in the aforesaid interval D = 32.0 ± 0.2 millimeters.

[0055] The closing upper wall 2 may comprise, in particular, a central portion that is concentric to the shell axis X and with a diameter of 23 millimeters.

[0056] An intersection line Y is considered between an outer surface (or outer side) of the aforesaid central portion with a diameter of 23 millimeters and a meridian section plane passing through the shell axis X. The intersection line Y may comprise, in particular, an upwardly convex portion (for example with an elliptical shape) with a radius of curvature included in a range 150 ± 0.1 millimeters.

[0057] A recess intersection line F is considered between an outer surface (or outer side) of the shell 1 and a meridian section plane passing through the shell axis X at a recess 6 (for example, the plane of section II corresponding to the plane of the sheet of Figure 2 or of Figure 4). The recess intersection line F may comprise, in particular, an outwardly convex portion situated in the annular connection wall 4 and an outwardly concave portion situated in the corrugated side wall 3 (see Figures 2 and 4).

[0058] A protrusion intersection line is considered (in this embodiment a line that includes the continuous line Z) between an outer surface of the shell 1 and a meridian section plane passing through the shell axis X at a protrusion 5 (for example, the plane of section III).

[0059] The protrusion intersection line (that includes the continuous line Z) may comprise, in particular, a rectilinear or outward convex portion situated in the corrugated side wall 3 and an outward concave portion arranged above the aforesaid rectilinear or outward convex portion (see Figure 3). The aforesaid outward concave portion may be, in particular, with a radius of curvature P smaller than 1.0 mm millimeters, or comprised between 0.5 and 1.0 millimeters.

[0060] The aforesaid outward concave portion may be arranged, in particular, in a transition zone between the annular connection wall 4 and the corrugated side wall 3.

[0061] The continuous line Z, along which the ridge of each protrusion 5 extends, may comprise, in particular, at least one straight portion coinciding with the segment AB.

[0062] The crown shell 1 is used, as said, to make a crown closure that may comprise, in addition to the shell 1, also a washer (not shown) applied to the inner surface of the shell. At least one part of the washer may be applied to the internal surface of a peripheral portion of the closing upper wall 2.

Claims

1. Shell (1) for crown closure, said shell comprising: a closing upper wall (2) configured to close an upper mouth of a container neck; a corrugated side wall (3) configured to be folded and to engage with an annular undercut arranged on the neck of the container; an annular connection wall (4) which connects said corrugated side wall (3) to said closing upper wall (2); said corrugated side wall (3) comprising a number N of corrugations defined by a succession of N protrusions (5) and N recesses (6) alternating with each other and arranged in a circumferential direction, each of said N recesses (6) comprising a bottom which is arranged on an internal surface of said shell (1), the bottom of each recess (6) ending below in a lower end point C, said lower end points C defining a lower end reference plane, each of said N protrusions (5) comprising an inclined ridge which is arranged on an external surface of said shell (1), each ridge ending below in a peripheral end point A, an intermediate point B being defined on each ridge located at an axial distance H from the respective peripheral end point A, said axial distance H being measured in a direction orthogonal to said reference plane E, said peripheral end point A and said intermediate point B defining a segment AB that forms an acute angle A with a plane G parallel to said reference plane E, said axial distance H being equal to 1 millimeter, said angle A being greater than 45°; said shell being characterized in that said number N of corrugations is odd and less than 19.

2. Shell according to claim 1, wherein said number N of corrugations is odd and less than 17, in particular equal to 15.

3. Shell according to claim 1 or 2, consisting of a sheet with a thickness of less than 0.17 millimeters, or less than 0.16 millimeters, or less than 0.15 millimeters, in particular equal to 0.15 millimeters or 0.14 millimeters.

4. Shell according to any one of the preceding claims, wherein said angle A is greater than 46.5°, or greater than 48°.

5. Shell according to any one of the preceding claims, wherein said lower end reference plane E is arranged at a distance K from the peripheral end point A of at least one protrusion (5), said distance K being less than 1.0 millimeters, or less than 0.9 millimeters.

6. Shell according to any one of the preceding claims, wherein said peripheral end points A of the ridges of said N protrusions (5) are arranged on the same plane V parallel to said reference plane E.

7. Shell according to any one of the preceding claims, wherein said lower end points C which define said reference plane E are arranged circumferentially around a shell axis X.

8. Shell according to claim 7, wherein, for each recess (6), said bottom extends along a continuous line Q and wherein, for each protrusion (5), said ridge extends along a continuous line Z, said continuous line Q being arranged on a plane passing through said shell axis X and orthogonal to said reference plane E, said continuous line Z being arranged on a plane passing through said shell axis X and orthogonal to said reference plane E.

9. Shell according to claim 8, wherein, considering a plane W orthogonal to said segment AB and passing through said point B or passing through a point of said continuous line Z located at a distance from said point B of less than 0.1 millimeters, considering a point D of intersection between said plane W and said continuous line Q, considering a straight line J coplanar with said continuous line Q and tangent to said continuous line Q in said point D, and considering an angle 0 between said straight line J and said lower end reference plane E, it is obtained that said angle 0 is equal to said angle A, or said angle 0 is comprised within an interval A ± 1°, or said angle 0 is comprised within an interval A ± 3°, or said angle 0 is comprised within an interval A ± 5°.

10. Shell according to any one of claims 7 to 9, wherein said closing upper wall (2) is upwardly convex, where “upwardly” refers to a position in which said corrugated side wall (3) is below said closing upper wall (2), and comprises a top point, said shell axis X passing through said top point and being orthogonal to said closing upper wall (2) at said top point.

11. Shell according to any one of claims 7 to 10, wherein a minimum diameter D circumscribed between said peripheral end points A of said protrusions (5) is comprised within an interval D = 32,10 ± 0.2 millimeters.

12. Shell according to any one of claims 7 to 11, wherein said closing upper wall (2) comprises a central portion that is concentric to said shell axis X and with a diameter of 23 millimeters, and wherein, considering an intersection line Y between an outer surface of said central portion and a meridian section plane passing through said shell axis X, said intersection line Y comprises an upwardly convex portion with a radius of curvature included in a range 150 ± 0.1 millimeters.

13. Shell according to any one of claims 7 to 12, wherein, considering a recess intersection line F between an outer surface of the shell (1) and a meridian section plane passing through said shell axis X at a recess (6), said recess intersection line F comprises an outward convex portion in said annular connection wall (4) and an outward concave portion in said corrugated side wall (3), and wherein considering a protrusion intersection line between an outer surface of the shell (1) and a meridian section plane passing through said shell axis X at a protrusion (5), said protrusion intersection line comprises a rectilinear or outward convex portion in said corrugated side wall (3) and an outward concave portion arranged above said rectilinear or outward convex portion, said outward concave portion being with a radius of curvature P smaller than 1.0 mm millimeters, or comprised between 0.5 and 1.0 millimeters; said outward concave portion being arranged, in particular, in a transition zone between said annular connection wall (4) and said corrugated side wall (3).

14. Shell according to any one of the preceding claims, wherein said continuous line Z along which said ridge extends comprises at least one straight portion coinciding with said segment AB.

15. Crown closure comprising a shell according to any one of the preceding claims.