Non-detachable fulcrum type liet tab for beverage container

Abstract

A rigid bend is provided in rigid body of lift tab between nose and lift ends. The bending axis of rigid bend and fulcrum line are in a vertical plane. A flexible transition piece is integrally connected to rigid body so that nose end and lift end of rigid body are at same initial height about equal to container rim height. Various installation means for achieving such configuration are provided. The initial height of lift end provides a finger access at lift end to allow user to raise lift end from initial height to optimum height above container rim height without encountering resistant force. The optimum height allows user to properly grasp lift end with force for initiating an initial rupture of score line.

1 . A lift tab comprising of:
 an elongated rigid body being divided into a forward nose section and a rearward lift section which are integrally jointed at a bend axis to form a first rigid bend with a first predetermined angle, said bend axis being perpendicular to a longitudinal axis of said lift tab, said forward nose section having a nose end at its forward end, and said rearward lift section having a lift end at its rearward end; and   a flexible transition piece being integrally connected to said rigid body, said transition piece being divided into a forward transition section and a rearward transition section which are integrally jointed at a fulcrum line perpendicular to said longitudinal axis of said lift tab, said forward transition section being deformed into a recessed rigid form, said rearward transition section being fixedly connected to an integral rivet of a top end wall of container immediately reward to said fulcrum line, said transition piece being only bendable about said fulcrum line;   wherein:   said bend axis of said rigid body and said fulcrum line being in parallel to each other in a nearly vertical plane; and   a means being provided to allow said transition piece to position said lift and nose ends at a first initial height about equal to a container rim height; and   said first initial height providing said lift end with a finger access, which allows an user to rotate said lift section upward by a second predetermined angle, to raise said lift end from said first initial height to a second optimum height, to rotate said nose section downward by said second predetermined angle, and to lower said nose end to a top surface of said top end wall with a minimum force for bending said transition piece about said fulcrum line, but without encountering resistance force from initiating an initial shear rupture of a small section of a score line in said top end wall; and   said second optimum height providing said lift end with a finger grasping ability, which allows said user to exert a lifting force at said lift end, and to cause said nose end to initiate said initial shear rupture of said small section of said score line for venting internal pressure of said container.   
   
   
       2 . In  claim 1 , said rearward transition section is provided relatively in parallel to said rearward lift section below a bottom surface of said rearward lift section prior to installing said lift tab to said top end wall of said container, and said means for installing said lift and nose ends at said first initial height consists of: first, placing said rearward lift section on top of said top end wall to receive said rivet, second, clamping said rivet, third, pressing said lift tab with a die until both said nose and lift ends making contact with a flat bottom surface of said die, fourth, pressing said lift tab with die until a bend being formed between said forward and rearward transition sections along said fulcrum line. 
   
   
       3 . In  claim 1 , said rearward transition section is provided below a bottom surface of said rearward lift section, having a second predetermined angle formed between said rearward transition section and said rearward lift section prior to installing said lift tab to said top end wall of said container, in which said second predetermined angle is determined by maintaining said nose and lift ends in a horizontal plane while maintaining said rearward transition section in another horizontal plane, and said means for installing said lift and nose ends at said first initial height consists of: first, providing a means of holding said lift tab with said nose and lift ends being in a horizontal plane while placing said lift tab on top of said top end wall to receive said rivet, second, clamping said rivet. 
   
   
       4 . In  claim 1 , said rearward transition section is provided with a bottom surface flush to a bottom surface of said rearward lift section prior to installing said lift tab to said top end wall of said container, and said means for installing said lift and nose ends at said first initial height is identical to said means provided in  claim 2 . 
   
   
       5 . In  claim 1 , said rearward transition section is provided with a bottom surface flush to a bottom surface of said rearward lift section at forward ends of said rearward transition section and rearward lift section, having a second predetermined angle formed between said rearward transition section and said rearward lift section prior to installing said lift tab to said top end wall of said container, in which said second predetermined angle is determined by maintaining said nose and lift ends in a horizontal plane while maintaining said rearward transition section in another horizontal plane, and said means for installing said lift and nose ends at said first initial height is identical to said means provided in  claim 3 . 
   
   
       6 . In  claim 1 , said second optimum height of said lift end is above said container rim height. 
   
   
       7 . In  claim 1 , an increase in said container rim height causes the same increase in said first initial height, and a much greater increase in said second optimum height, so that said increase in said container rim height provides an alternative means for improving the accessing and operating ability of said lift tab. 
   
   
       8 . In  claim 1 , said small section of said score line is located immediately forward to said rivet. 
   
   
       9 . In  claim 1 , said lift end is further raised upward from said second optimum height to a third height after completion of said initial rupture of said small section of said score line, and said third height also provides said lift end with finger grasping ability that allows said user to exert a relatively large force to propagate shear rupture of the remaining section of said score line. 
   
   
       10 . In  claim 9 , after completion of said propagation of shear rupture of said remaining section of said score line, a broken section of said top end wall is hinged to said top end wall in a relatively vertical position within said container, and said lift end is restored to a final position without interfering drinking ability of said container.