Metallic container dome configured to deform at a predetermined pressure

Abstract

Methods and apparatus for forming a metallic dome are provided. More specifically, the present invention relates to a metallic dome that may be used to seal an aerosol container. The metallic dome includes a novel flattened relief panel and an inwardly oriented arch configured to deform in response to pressure within the aerosol container exceeding a predetermined amount. In one embodiment, the flattened relief panel is substantially planar. Optionally, the metallic dome includes at least a first inwardly oriented arch with a first radius of curvature and a second inwardly oriented arch with a second radius of curvature.

Claims

1. A forming tool to shape a metallic dome for an aerosol container, the metallic dome having a geometry configured to deform in response to a predetermined pressure within the aerosol container, comprising: a body portion configured to be interconnected to a tooling assembly; and a face portion to shape an inwardly oriented arch of the metallic dome, the face portion having a first diameter and including: a first outwardly oriented arch with a first radius of curvature; a second outwardly oriented arch interconnected to the first outwardly oriented arch, the second outwardly oriented arch having a second radius of curvature wherein the second radius of curvature is less than the first radius of curvature; and a flattened portion, interconnected to the second outwardly oriented arch, wherein the flattened portion is substantially linear and includes a second diameter that is between 17.0% and 21.0% of the first diameter.

2. The forming tool of claim 1, wherein the face portion further comprises a third outwardly oriented arch interconnected between the second outwardly oriented arch and the flattened portion, the third outwardly oriented arch having a third radius of curvature that is greater than the first radius of curvature.

3. The forming tool of claim 2, wherein the face portion further comprises a fourth outwardly oriented arch interconnected between the third outwardly oriented arch and the flattened portion, the fourth outwardly oriented arch having a fourth radius of curvature that is one-fifth of the third radius of curvature.

4. The forming tool of claim 1, wherein the second radius of curvature is less than one-fourth of the first radius of curvature.

5. The forming tool of claim 1, wherein the second radius of curvature is one-fifth of the first radius of curvature.

6. The forming tool of claim 1, wherein the second radius of curvature has a center forming a third diameter, the third diameter being between 65% and 70% of the first diameter.

7. The forming tool of claim 1, wherein the flattened portion is configured to form a flattened relief panel in the metallic dome, wherein the exterior surface of the flattened relief panel is not scored.

8. The forming tool of claim 7, wherein the forming tool is configured to form a metallic dome that is devoid of scores and coins.

9. The forming tool of claim 1, wherein the flattened portion is configured to form a flattened relief panel in the metallic dome, wherein the flattened relief panel has a relief panel diameter which is between 18.0% and 19.4% of an interior diameter of a peripheral curl.

10. The forming tool of claim 1, wherein the flattened portion is configured to form a corresponding flattened relief panel in the metallic dome, wherein the flattened relief panel has a surface area which is between 2.0% and 5.6% of the surface area of the metallic dome.

11. The forming tool of claim 1, wherein the forming tool is configured to form a metallic dome that has a height that is between 15% and 18.5% of an outermost diameter of a peripheral curl.

12. The forming tool of claim 1, wherein the flattened portion is substantially centered on a longitudinal axis of the forming tool.

13. A forming tool to shape a metallic dome for an aerosol container, the metallic dome having a geometry configured to deform in response to a predetermined pressure within the aerosol container, comprising: a body portion configured to be interconnected to a tooling assembly; and a face portion to shape an inwardly oriented arch of the metallic dome, the face portion having a first diameter and including: a first outwardly oriented arch with a first radius of curvature; a second outwardly oriented arch interconnected to the first outwardly oriented arch, the second outwardly oriented arch having a second radius of curvature; a flattened portion which is substantially linear and including a second diameter that is between 17.0% and 21.0% of the first diameter; a third outwardly oriented arch interconnected to the second outwardly arch, the third outwardly oriented arch having a third radius of curvature that is greater than the first radius of curvature; and a fourth outwardly oriented arch interconnected to the third outwardly oriented arch and to the flattened portion, the fourth outwardly oriented arch having a fourth radius of curvature that is one-fifth of the third radius of curvature.

14. The forming tool of claim 13, wherein the second radius of curvature is less than one-fourth of the first radius of curvature.

15. The forming tool of claim 13, wherein the second radius of curvature is one-fifth of the first radius of curvature.

16. The forming tool of claim 13, wherein the second radius of curvature has a center forming a third diameter, wherein the third diameter is between 65% and 70% of the first diameter.

17. The forming tool of claim 13, wherein the flattened portion is configured to form a flattened relief panel in the metallic dome, wherein the exterior surface of the flattened relief panel is not scored.

18. The forming tool of claim 17, wherein the forming tool is configured to form a metallic dome that is devoid of scores and coins.

19. The forming tool of claim 13, wherein the flattened portion is configured to form a flattened relief panel in the metallic dome, wherein the flattened relief panel has a relief panel diameter which is between 18.0% and 19.4% of an interior diameter of a peripheral curl.

20. The forming tool of claim 13, wherein the flattened portion is configured to form a flattened relief panel in the metallic dome, wherein the flattened relief panel has a surface area which is between 2.0% and 5.6% of the surface area of the metallic dome.

21. The forming tool of claim 13, wherein the forming tool is configured to form a metallic dome that has a height that is between 15% and 18.5% of an outermost diameter of a peripheral curl.

22. The forming tool of claim 13, wherein the flattened portion is substantially centered on a longitudinal axis of the forming tool.

23. A forming tool to shape a metallic dome for an aerosol container, the metallic dome having a geometry configured to deform in response to a predetermined pressure within the aerosol container, comprising: a body portion configured to be interconnected to a tooling assembly; and a face portion to shape an inwardly oriented arch of the metallic dome, the face portion having a first diameter and including: a first outwardly oriented arch with a first radius of curvature, wherein the first radius of curvature is consistent, wherein the first outwardly oriented arch extends from a countersink forming portion of the face; a second outwardly oriented arch interconnected to the first outwardly oriented arch, the second outwardly oriented arch having a second radius of curvature, wherein the second radius of curvature is less than the first radius of curvature, and wherein the second radius of curvature is consistent; and a flattened portion interconnected to the second outwardly oriented arch, wherein the flattened portion is substantially linear and including a second diameter that is between 17.0% and 21.0% of the first diameter.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The accompanying drawings, which are incorporated herein and constitute a part of the specification, illustrate embodiments of the invention and together with the Summary of the Invention given above and the Detailed Description given below serve to explain the principles of these embodiments. In certain instances, details that are not necessary for an understanding of the disclosure or that render other details difficult to perceive may have been omitted. It should be understood, of course, that the present invention is not necessarily limited to the particular embodiments illustrated herein. Additionally, it should be understood that the drawings are not necessarily to scale.

(2) FIG. 1A is a cross-sectional view of a prior art container body and a metallic dome of an aerosol container;

(3) FIG. 1B is a cross-sectional view of another prior art container body and metallic dome for an aerosol container;

(4) FIG. 2 is a cross-sectional view of a tooling assembly including a forming tool of one embodiment of the present invention;

(5) FIG. 3 is an expanded perspective view of a portion of the forming tool and other tools of the tooling assembly of FIG. 2 shaping a metallic dome of the present invention;

(6) FIG. 4 is a front elevation view of the forming tool and metallic dome of FIG. 3 in relation to other tools of the tooling assembly;

(7) FIG. 5 is a bottom plan view of the forming tool of FIG. 2;

(8) FIG. 6 is a cross-sectional view of the forming tool taken along line 6-6 of FIG. 5;

(9) FIG. 7 is a cross-sectional elevation view of a metallic dome of one embodiment of the present invention taken along a diameter of the metallic dome;

(10) FIG. 8 is an expanded view of a peripheral portion of the metallic dome of FIG. 7 before a peripheral curl is formed on the metallic dome;

(11) FIG. 9 is another expanded view of the peripheral portion of the metallic dome of FIG. 8 after the peripheral curl is at least partially formed;

(12) FIG. 10 is a perspective view of a two-piece aerosol container of one embodiment of the present invention, the aerosol container including a metallic dome of the present invention interconnected to a container body of the aerosol container;

(13) FIG. 11 is a front elevation view of the two-piece aerosol container of FIG. 10;

(14) FIG. 12 is a cross-sectional view of the two-piece aerosol container taken along line 12-12 of FIG. 11;

(15) FIGS. 13A, 13B are photographs of a two-piece aerosol container of one embodiment of the present invention showing a metallic dome of the present invention which has deformed outwardly to relieve pressure within the aerosol container;

(16) FIGS. 14A, 14B are photographs of another two-piece aerosol container in which a metallic dome of one embodiment of the present invention has deformed outwardly to reduce pressure and subsequently separated partially from the container body as pressure continued to increase within the aerosol container; and

(17) FIGS. 15A-15C illustrate forces experienced by a metallic dome of the present invention when pressure within an aerosol container is at various levels.

(18) To assist in the understanding of one embodiment of the present invention the following list of components and associated numbering found in the drawings is provided herein:

NUMBER COMPONENT

(19) 2 Aerosol container

(20) 4 Container body

(21) 6 Open end

(22) 8 Sidewall

(23) 10 Shoulder

(24) 12 Opening

(25) 14 Metallic dome

(26) 16 Inwardly oriented arch

(27) 18 Tooling assembly

(28) 20 Lift ring

(29) 22 Draw punch

(30) 24 Draw punch insert

(31) 26 Forming tool

(32) 28 Longitudinal axis

(33) 30 Height of forming tool

(34) 32 Body portion

(35) 34 Body Diameter

(36) 36 Body Height

(37) 38 Distal end of body

(38) 40 Face of forming tool

(39) 42 Diameter of face portion

(40) 44 Flattened portion

(41) 46 Diameter of flattened portion

(42) 50 Outwardly oriented arch

(43) 52 First outwardly oriented arch

(44) 54 Second outwardly oriented arch

(45) 56 Third outwardly oriented arch

(46) 58 Fourth outwardly oriented arch

(47) 60 Second radius of curvature center diameter

(48) 62 Fourth radius of curvature center diameter

(49) 66 Metallic dome

(50) 68 Height of metallic dome

(51) 70 Peripheral curl

(52) 72 Curl diameter

(53) 74 Countersink

(54) 76 Countersink or interior diameter

(55) 77 Countersink radius of curvature center

(56) 78 Countersink depth

(57) 80 Arched portion

(58) 82 First inwardly oriented arch

(59) 84 Second inwardly oriented arch

(60) 86 Third inwardly oriented arch

(61) 88 Fourth inwardly oriented arch

(62) 90 Flattened relief panel

(63) 92 Diameter of flattened relief panel

(64) 94 Brim

(65) 96 Brim width

(66) 102 Aerosol container

(67) 104 Container body

(68) 106 Open end

(69) 108 Sidewall

(70) 110 Shoulder

(71) 112 Opening

(72) 114 Seam

(73) 116 Gap

(74) 120 Stress scale

(75) 122 Line indicated predicted yield strength

(76) 124 First portion of arch

(77) 126 Second portion of arch

(78) R1 First radius of curvature

(79) C1 Center of first radius of curvature

(80) R2 Second radius of curvature

(81) C2 Center of second radius of curvature

(82) R3 Third radius of curvature

(83) C3 Center of third radius of curvature

(84) R4 Fourth radius of curvature

(85) C4 Center of fourth radius of curvature

DETAILED DESCRIPTION

(86) The present invention has significant benefits across a broad spectrum of endeavors. It is the Applicant's intent that this specification and the claims appended hereto be accorded a breadth in keeping with the scope and spirit of the invention being disclosed despite what might appear to be limiting language imposed by the requirements of referring to the specific examples disclosed. To acquaint persons skilled in the pertinent arts most closely related to the present invention, a preferred embodiment that illustrates the best mode now contemplated for putting the invention into practice is described herein by, and with reference to, the annexed drawings that form a part of the specification. The exemplary embodiment is described in detail without attempting to describe all of the various forms and modifications in which the invention might be embodied. As such, the embodiments described herein are illustrative, and as will become apparent to those skilled in the arts, may be modified in numerous ways within the scope and spirit of the invention.

(87) Referring now to FIG. 2, a tooling assembly 18 with a forming tool 26 of one embodiment of the present invention is generally illustrated. The forming tool 26 is positioned proximate to a lift ring 20. A draw punch 22 with a draw punch insert 24 is positioned in an opposing relationship to the forming tool 26. The forming tool 26, lift ring 20, draw punch 22, and draw punch insert 24 are generally concentrically aligned with a longitudinal axis of the tooling assembly.

(88) Referring now to FIGS. 3-4, expanded views of the forming tool 26 forming a metallic dome 66 of one embodiment of the present invention are illustrated. A face 40 of the forming tool 26 has a shape configured to form or shape a predetermined geometry in the metallic dome 66. The lift ring 20, draw punch 22, draw punch insert 24, and the forming tool 26 also interact to form a peripheral curl 70 and countersink 74 with predetermined geometries on the metallic dome 66. In one embodiment, generally illustrated in FIG. 4, at least a flattened relief panel 90 of the metallic dome is spaced from the draw punch insert 24 when the forming tool 26 shapes the metallic dome 66. More specifically, in one embodiment, the draw punch insert 24 only contacts a radially outward portion of the metallic dome 66. The portion of the metallic dome 66 contacted by the draw punch insert 24 is closer to the countersink 74 than to the flattened relief panel 90. In one embodiment, only an annular ring of the draw punch insert 24 contacts the metallic dome during forming by the tooling assembly 18.

(89) Referring now to FIG. 5-6, one embodiment of a forming tool 26 of the present invention is illustrated. The forming tool 26 is sized to shape a metallic dome 66 configured to seal a 210 diameter aerosol container. However, as one of skill in the art will appreciate, the dimensions of the forming tool 26 may be altered to shape metallic domes sized to seal aerosol containers of other diameters. The forming tool 26 generally includes a body portion 32 configured to be interconnected to the tooling assembly 18. In one embodiment of the present invention, the forming tool 26 has a body portion 32 configured to be interconnected to a prior art tooling assembly in place of a prior art dome forming tool. In this manner, the prior art tooling assembly can be adapted to form metallic domes 66 of the present invention by substitution of only one prior art tool in the tooling assembly with the forming tool 26 of one embodiment of the present invention.

(90) Referring now to FIG. 6, some dimensions of the forming tool 26 are described. Applicant has found that the geometry of features of the face 40 must have specific proportional relationships to shape metallic domes 66 that consistently deform outwardly at predetermined pressures and without prematurely buckling or buckling only partially.

(91) The forming tool 26 has a predetermined height 30 and maximum diameter 42. In one embodiment, the height 30 is between approximately 2.1 inches and approximately 2.4 inches. In another embodiment, the maximum diameter 42 is between approximately 2.3 inches and approximately 2.6 inches. The body portion 32 has an exterior diameter 34 of between approximately 2.0 inches and approximately 2.3 inches and a height 36 of between approximately 1.35 inches and approximately 1.65 inches. The height 30, diameter 34, and shape of the body portion 32 may be changed as necessary for interconnection to various tooling assemblies.

(92) The face 40 includes an outwardly oriented arch 50 and a flat portion 44. The flat portion 44 is substantially planar and generally centered on a longitudinal axis 28 of the forming tool 26. The flat portion 44 has a predetermined diameter 46. In one embodiment, the diameter 46 of the flat portion 44 has a predetermined relationship to the maximum diameter 42 of the forming tool 26. More specifically, in one embodiment, the flat portion diameter 46 is between approximately 17.0 percent and approximately 21.0 percent of the forming tool diameter 42. Additionally, or alternatively, in another embodiment, the diameter 46 is between approximately 0.40 inches and approximately 0.58 inches. In another embodiment, the flat portion diameter 46 is between approximately 0.43 inches and approximately 0.49 inches.

(93) In one embodiment, the outwardly oriented arch 50 has a substantially constant radius of curvature. Alternatively, the face 40 includes one or more of a first outwardly oriented arch 52 with a first radius of curvature R1, a second outwardly oriented arch 54 with a second radius of curvature R2, and a third outwardly oriented arch 56 with a third radius of curvature R3. Optionally, the face 40 may also include a fourth outwardly oriented arch 58 with a fourth radius of curvature R4.

(94) In one embodiment, the first radius of curvature R1 is at least approximately three times greater than the second radius of curvature R2. In another embodiment, the second radius of curvature R2 is approximately one-fifth (or 20 percent) of the first radius of curvature R1.

(95) In another embodiment, the first radius of curvature R1 is less than the third radius of curvature R3. In one embodiment, the first radius of curvature R1 is approximately 75% of the third radius of curvature R3. Optionally, the second radius of curvature R2 may be approximately 15% of the third radius of curvature R3.

(96) In one embodiment, the fourth radius of curvature R4 is less than each of the first radius of curvature R1 and the third radius of curvature R3. Accordingly, in one embodiment, the third radius of curvature R3 is at least approximately three times greater than the fourth radius of curvature R4. In another embodiment, the fourth radius of curvature R4 is approximately 20 percent of the third radius of curvature R3. In yet another embodiment, the relationship of radii of curvature R1-R4 may be described as:

(97) $\left(\frac{4}{3}\times R1\right)\approx \left(\frac{20}{3}\times R2\right)\approx R3\approx \left(5\times R4\right)$

(98) The second and fourth radii of curvature R2, R4 have respective second and fourth centers C2, C4 which are offset from the longitudinal axis 28 of the forming tool 26 by predetermined amounts. The centers C2, C4 define diameters 60, 62 with specific relationships to the forming tool diameter 42. More specifically, in one embodiment, the second centers C2 of the second radius of curvature R2 define a diameter 60 that is between approximately 65% and approximately 70% of the forming tool diameter 42. In another embodiment, the fourth centers C4 of the fourth radius of curvature R4 define diameter 62 that is between approximately 15% and approximately 18.5% of the forming tool diameter 42. In one embodiment, diameter 62 is between approximately 21% and approximately 25% of diameter 60.

(99) In one embodiment, the first radius of curvature R1 is between approximately 1.7 inches and approximately 2.1 inches or, in another embodiment, between approximately 1.8 inches and approximately 2.0 inches. A first center C1 of the first radius of curvature R1 may optionally be offset from the longitudinal axis 28 by less than approximately 0.1 inches. The first center C1 may be positioned within the forming tool 26 and between approximately 0.2 inches and approximately 0.7 inches from a distal end 38 of the body portion 32.

(100) Optionally, the second radius of curvature R2 may be between approximately 0.2 inches and approximately 0.6 inches or, in another embodiment, between approximately 0.3 and approximately 0.5 inches. The second center C2 of the second radius of curvature R2 is offset from the longitudinal axis 28 by between approximately 0.75 inches and approximately 0.92 inches. In one embodiment, the second center C2 of the second radius of curvature R2 is within the forming tool 26 and separated from the body distal end 38 by between approximately 1.60 inches and approximately 1.85 inches.

(101) The third radius of curvature R3 optionally is between approximately 2.25 inches and approximately 2.75 inches. In another embodiment, the third radius of curvature R3 is between approximately 2.4 inches and approximately 2.6 inches. The third center C3 of the third radius of curvature R3 is positioned between approximately 0.1 inches and approximately 0.4 inches beyond the distal end 38 of the body portion 32 outside of the forming tool 26.

(102) In one embodiment, the fourth radius of curvature R4 is between approximately 0.3 inches and approximately 0.7 inches. Optionally, the fourth radius of curvature R4 is between approximately 0.4 inches and approximately 0.6 inches. Fourth centers C4 of the fourth radius of curvature R4 are positioned within the forming tool 26 and spaced from the longitudinal axis 28 by between approximately 0.05 inches and approximately 0.35 inches.

(103) Referring now to FIG. 7, a metallic dome 66 of one embodiment of the present invention shaped by the forming tool 26 of FIGS. 5-6 is illustrated. The metallic dome 66 generally includes a peripheral curl 70, a countersink 74, an inwardly oriented arch 80 and a flattened relief panel 90. In one embodiment, no scores, coins, or areas of weakness are formed on the metallic dome. In another embodiment, the inwardly oriented arch 80 is free of scores, coins, and weakened areas. In yet another embodiment, the flattened relief panel 90 does not include scores, coins, or areas of weakness.

(104) The metallic dome 66 has a predetermined height 68 and curl diameter 72. In one embodiment, the height 68 is between approximately 15% and approximately 18.5% of the curl diameter 72. Optionally, the height 68 is between approximately 0.30 inches and approximately 0.66 inches or between approximately 0.45 inches and approximately 0.51 inches. In one embodiment, the peripheral curl diameter 72 is between approximately 2.8 inches and approximately 2.98 inches. The countersink 74 defines an interior diameter 76 of the metallic dome 66. In one embodiment, the metallic dome may have an interior diameter 76 of between approximately 2.3 inches and approximately 2.65 inches. In one embodiment, the interior diameter 76 is measured at a tangency point of the chuckwall angle and a center 77 of the countersink radius of curvature (illustrated in FIG. 9).

(105) The flattened relief panel 90 is substantially planar and generally centered within the dome 80. The flattened relief panel 90 has a diameter 92. The diameter 92 is measured from a sharp corner of the arched portion. In one embodiment, diameter 92 is between approximately 0.39 inches and approximately 0.52 inches. In another embodiment, the flattened relief panel diameter 92 is between approximately 18% and approximately 20% of the countersink diameter 76. Alternatively, in another embodiment, the flattened relief panel diameter 92 is between approximately 18.2% and approximately 19.2% of the countersink diameter 76. In one embodiment, the flattened relief panel 90 has a surface area that is between approximately 2.0% and approximately 5.6% of a surface area of the metallic dome 66.

(106) In one embodiment, the inwardly oriented arch 80 has a substantially constant radius of curvature. Alternatively, the metallic dome 66 may include one or more inwardly oriented arches 82, 84, 86, 88. Each of the inwardly oriented arches 82-88 may have different radii of curvature which have been formed to increase the overall performance and yield strength of the dome. In one embodiment, the first inwardly oriented arch 82 has a radius of curvature of between approximately 1.5 inches and approximately 2.3 inches. In another embodiment, the second inwardly oriented arch 84 has a radius of curvature of between approximately 0.18 inches and approximately 0.66 inches. The third inwardly oriented arch 86, in one embodiment, has a radius of curvature of between approximately 2.0 inches and approximately 3.0 inches. In still another embodiment, the fourth inwardly oriented arch 88 has a radius of curvature of between approximately 0.27 inches and approximately 0.77 inches. As will be appreciated by one of skill in the art, the arches 82, 84, 86, 88 can have a variety of other radii depending on the type or thickness of material used to form the dome, the size of the dome, the size of the container, the amount of interior pressure the container is designed to hold, the volume of the container, and the type of product stored within the container. Accordingly, the arches 82, 84, 86, 88 may have other radii of curvature in different embodiments.

(107) The flattened relief panel 90 is interconnected to an innermost portion of one of the inwardly oriented arches 82-88. In one embodiment, the flattened relief panel 90 is interconnected to an innermost portion of the fourth inwardly oriented arch 88. Alternatively, the flattened relief panel 90 is interconnected to an innermost portion of the third inwardly oriented arch 86.

(108) In one embodiment, the first inwardly oriented arch 82 is shaped by the first outwardly oriented arch 52 of the forming tool 26. Similarly, the second inwardly oriented arch 84 can be shaped by the second outwardly oriented arch 54, the third inwardly oriented arch 86 can be shaped by the third outwardly oriented arch 56, and the fourth inwardly oriented arch 88 can be shaped by the fourth outwardly oriented arch 58.

(109) Referring now to FIG. 8, before the peripheral curl is formed, the metallic dome 66 may have a brim 94 with a width 96 of between approximately 0.18 inches and approximately 0.38 inches. As shown in FIG. 9, in one embodiment the countersink 74 has a depth 78 of between approximately 0.06 inches and approximately 0.18 inches. Optionally, the countersink radius of curvature is approximately 0.025 inches and is substantially centered at point 77. In another embodiment, the countersink radius of curvature is between approximately 0.020 inches and approximately 0.040 inches.

(110) Referring now to FIGS. 10-12, a two-piece aerosol container 102 of one embodiment of the present invention is illustrated. As will be appreciated by one of skill in the art, the aerosol container 102 may be of any size and shape. Specifically, the metallic dome 66 of embodiments of the present invention can be use with a container 102 of any size or shape and configured to hold any type of product. In one embodiment, the aerosol container 102 generally includes a container body 104 with an open end 106 sealed by a metallic dome 66. The container body 104 also includes a sidewall 108 that is substantially cylindrical, a shoulder 110 with a decreased diameter, and an opening 112 at an uppermost portion of the shoulder 110. The sidewall 108 proximate to the open end 106 may have a decreased diameter. The metallic dome 66 of one embodiment of the present invention has been interconnected to the sidewall 108 at the open end 106. The metallic dome 66 may be seamed 114 to the sidewall 108 by methods known to those of skill in the art. In one embodiment, the seam 114 is a double seam which interconnects the metallic dome 66 to the container body 104. The aerosol container 102 may be of any diameter and height. Further, other shapes of the shoulder 110 are contemplated. In another embodiment, the aerosol container 102 may include an upper end closure seamed to the container body 108 to form a 3-piece aerosol container.

(111) Referring now to FIGS. 13A, 13B, photographs of an aerosol container 102 of the present invention are provided. The pressure within the aerosol container 102 was increased to test the ability of the metallic dome 66 to deform to relieve pressure within the aerosol container. In response to the increased pressure, the metallic dome 66 deformed outwardly to increase the volume of the aerosol container 102 and decrease the pressure within the aerosol container. The metallic dome 66 deformed at less than approximately 275 psig. More specifically, the metallic dome 66 deformed when the pressure within the aerosol container 102 reached between approximately 225 psig and approximately 230 psig. The seam 114 which interconnects the metallic dome 66 to the sidewall 108 did not unravel or vent the gas from within the aerosol container 102. Additionally, no sharp edges were created on the end closure 66 when the inwardly oriented arch 80 deformed outwardly.

(112) Referring now to FIGS. 14A, 14B, photographs of another aerosol container 102 of the present invention are provided. The metallic dome 66 was tested to failure by increasing the pressure within the container beyond approximately 275 psig. More specifically, pressure within the aerosol container 102 was increased until the metallic dome 66 deformed outwardly at approximately 225 psig. Pressure within the aerosol container 102 decreased due to the increased volume associated with the outward deformation of the metallic dome 66. However, pressure within the container 102 was then further increased and the metallic dome 66 continued to distend outwardly. The metallic dome 66 of FIG. 14 accordingly deformed outwardly a greater distance than the metallic dome 66 of FIG. 13. When pressure within the container 102 reached between approximately 275 psig, and approximately 280 psig, the seam 114 unraveled forming a gap 116 between the metallic dome 66 and the sidewall 108. Pressure within the aerosol container 102 decreased as gas vented through the gap 116.

(113) Referring now to FIGS. 15A-15C, forces on a metallic dome 66 of the present invention at different pressures within an aerosol container are generally illustrated in finite element analysis plots. The aerosol container to which the metallic dome is interconnected is not illustrated for clarity. As will be appreciated by one of skill in the art, the metallic dome 66 can be interconnected to aerosol containers of a variety of sizes and shapes. The metallic dome 66 will fail when the material of the peripheral curl 70 yields as a result of excessive internal pressure. The predicted yield strength of the material of the metallic dome is approximately

(114) $1.850\times {10}^8\frac{N}{m^2}.$
Stress scale 120 illustrates stresses on the metallic dome 66 measured in

(115) $\frac{N}{m^2}.$
The predicted yield strength of

(116) $1.850\times {10}^8\frac{N}{m^2}$
is indicated by line 122 on the stress scale 120.

(117) FIG. 15A illustrates forces on a metallic dome 66 when pressure within the aerosol container is less than 220 PSIG. As illustrated, the stress on the metallic dome 66 is less than the yield strength of approximately

(118) $1.850\times {10}^8\frac{N}{m^2}$
when pressure in the container is less than 220 PSIG. Accordingly, the arched portion 80 does not buckle and the peripheral curl 70 retains its shape preventing release of product from the container.

(119) FIG. 15B illustrates the metallic dome 66 of FIG. 15A when pressure within the aerosol container is approximately 220 PSIG. Stress at a first portion 124 of the arched portion 80 exceeds approximately

(120) $1.199\times {10}^9\frac{N}{m^2}$
and stress at a second portion 126 near the peripheral curl 70 exceeds approximately

(121) $2.199\times {10}^9\frac{N}{m^2}.$
Accordingly, the inwardly oriented arch 80 of the metallic dome has begun to deform outwardly, increasing the volume of the aerosol container and decreasing pressure within the aerosol container. However, the stress at the peripheral curl 70 is less than the yield strength of

(122) $1.850\times {10}^8\frac{N}{m^2}$
and the peripheral curl has retained its shape, preventing the release of product from within the container.

(123) FIG. 15C illustrates the metallic dome of FIGS. 15A, 15B when pressure within the aerosol container is increased to approximately 280 PSIG. As the pressure increased above 220 PSIG, stress on the peripheral curl 70 increases to greater than approximately

(124) $4.198\times {10}^9\frac{N}{m^2}$
and the inwardly oriented arch 80 has distended outwardly further than in FIG. 15B. At approximately 280 PSIG, the material of the peripheral curl 70 has yielded and separated at least partially from the container body. More specifically, the aerosol container burst and pressure released from the aerosol container.

(125) The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limiting of the invention to the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments described and shown in the figures were chosen and described in order to best explain the principles of the invention, the practical application, and to enable those of ordinary skill in the art to understand the invention.

(126) While various embodiments of the present invention have been described in detail, it is apparent that modifications and alterations of those embodiments will occur to those skilled in the art. Moreover, references made herein to “the present invention” or aspects thereof should be understood to mean certain embodiments of the present invention and should not necessarily be construed as limiting all embodiments to a particular description. It is to be expressly understood that such modifications and alterations are within the scope and spirit of the present invention, as set forth in the following claims.