Container with concentric segmented can bottom

Abstract

A container including a sidewall and an end panel is provided. The end panel includes a center panel, an elastic portion, and a frustoconical transition portion. The center panel and the elastic portion are configured to transition between a first configuration and a second configuration.

What is claimed is: 
     
         1 . A metal can body comprising:
 a cylindrical, metal sidewall having a circular cross-section which defines a volume;   a circular, metal end panel that closes one end of the cylindrical sidewall, the end panel including:
 a circular center panel having a perimeter defined by a bead and a first plane contacting a surface of the panel; 
 an annular, elastic portion extending from the sidewall to a boundary and having a second plane substantially perpendicular to the sidewall and contacting the elastic portion, the elastic portion including a plurality of ridges substantially concentric with the sidewall; 
 a frustoconical transition portion extending from the boundary to the bead connecting the center panel and the elastic portion such that the first plane is offset from the second plane to support the center panel at a first position in the interior; 
 the center panel being moveable from the first position to a second position by a force exerted from the interior upon the end panel, the second position being outside of the volume, and the center panel returnable to the first position when the force is reduced. 
   
     
     
         2 . The can body of  claim 1 , wherein the metal is one of steel and aluminum. 
     
     
         3 . The can body of  claim 2 , wherein the concentric ridges are uniformly spaced. 
     
     
         4 . The can body of  claim 2 , wherein there are at least five ridges in the elastic portion. 
     
     
         5 . The can body of  claim 4 , wherein the sidewall has a first radius from the center of the center panel, the perimeter has a second radius which is between 50% and 60% of the first radius, and the boundary has a third radius between 20% and 30% of the first radius. 
     
     
         6 . The can body of  claim 5 , wherein the transition portion extends from the center panel at an angle of between 17° and 21° when the center panel is in the first position. 
     
     
         7 . The can body of  claim 4 , wherein the metal sidewall and the end panel are joined together at the sidewall with a double seam. 
     
     
         8 . The can body of  claim 4 , wherein the metal sidewall and the end panel are integrally formed. 
     
     
         9 . A method of filing a can comprising:
 providing a can body having a sidewall extending along a longitudinal axis from a first open end to a second end and an end panel sealing the second end, the end panel having a center panel portion in a first configuration extending along a first plane, a transition portion extending radially outwardly from the center panel portion, and a radially outer elastic portion extending between the transition portion and the sidewall along a second plane, the second plane being non-coplanar with the first plane;   filling the can body;   coupling a can end to the sidewall to hermetically seal the can body;   heating the contents of the sealed can body, wherein the increased pressure inside the can body resulting from the heating causes the center panel portion to transition from the first configuration to a second configuration in which the center panel portion extends along a third plane on an opposite side of the second plane than the first plane;   wherein the second plane and the third plane are non-coplanar;   cooling the contents of the sealed can body; and   applying a force to the center panel portion toward the first plane causing the center panel portion to transition from the second configuration to the first configuration.   
     
     
         10 . The method of  claim 9 , wherein the heating step includes heating the contents of the container by induction. 
     
     
         11 . A can body comprising:
 a sidewall extending along a longitudinal axis from a first open end to a second end; and   an end panel closing the second end of the sidewall, the end panel including an outer annular portion including a plurality of ridges, a frustoconical portion extending radially inwardly from the outer annular portion at a first angle, and a center portion extending from the frustoconical portion;   wherein the center portion is configured to be displaced between a first configuration in which the center portion is located above the lower axial periphery of the sidewall and a second configuration in which the center portion is located below the lower axial periphery of the sidewall.   
     
     
         12 . The can body of  claim 11 , wherein the end panel has a first diameter and wherein the center portion has a second diameter;
 wherein the second diameter is between 20% and 30% of the first diameter.   
     
     
         13 . The can body of  claim 11 , wherein the outer annular portion includes a plurality of ridges generally concentric with the sidewall; and
 wherein the center portion has a perimeter defined by a bead generally concentric with the sidewall.   
     
     
         14 . The can body of  claim 11 , wherein the outer annular portion extends along a first plane;
 wherein the frustoconical portion extends at a first angle to the first plane when the center portion is in the first configuration; and   wherein the first angle is between 17° and 21°.   
     
     
         15 . The can body of  claim 11 , wherein the can body has a first height;
 wherein the center portion in the first configuration extends along a second plane;   wherein the second plane is a second height above the first plane; and   wherein the second height is between 2% and 3% of the first height.   
     
     
         16 . The can body of  claim 11 , wherein the outer annular portion is configured to allow the center portion to transition between the first configuration and the second configuration and to resume its shape prior to the transition after the transition. 
     
     
         17 . The can body of  claim 11 , wherein the center portion is configured to transition from the first configuration to the second configuration when the pressure inside the can body is between 35 psig and 40 psig. 
     
     
         18 . The can body of  claim 11 , wherein the outer annular portion includes six ridges. 
     
     
         19 . The can body of  claim 11 , wherein the end panel is coupled to the sidewall by a double seam. 
     
     
         20 . The can body of  claim 11 , wherein the end panel is configured to allow the center portion to transition between the first configuration and the second configuration without permanently deforming the end panel; and
 wherein the end panel is configured so that the center portion is maintained in the second configuration when the interior pressure of the can body decreases.