Patent ID: 6561004
Filing Date: 2003-05-13
Classification: B21D,B65D

Abstract:
A method of forming a double seam joining a can body to a can lid, the can lid having a center panel having a central axis that is perpendicular to a diameter of the outer rim of said lid, an annular countersink portion extending radially outward from said center panel, an arcuate portion extending radially outward from the annular countersink wherein a line passing through the ends of said arcuate portion is at an angle with respect to said central axis of the center panel of from about 20Â° to about 80Â°, a step portion extending radially outward from the arcuate portion, a first transitional portion extending radially outward from said step portion, a second transitional portion extending radially outward from the first transitional portion to a peripheral curl, and the can body having a can body flange, comprising the steps of:supporting the can body on a base plate; positioning the can lid on the can body with the second transitional portion resting on the can body flange; providing a chuck having a lower portion, an upper portion, and a recessed portion extending between the lower portion and the upper portion, the upper portion of the chuck having a frustoconical portion and a driving surface that is configured to contact the step portion of the lid, the recessed portion of the chuck being configured not to deform said arcuate portion of said can lid during forming of the seam, and the lower portion of the chuck configured to contact a surface of said annular countersink at a chuck contacting portion when the chuck is in engagement with the can lid; engaging the can lid with the chuck; rotating the can and lid assembly using the chuck; rolling the peripheral curl and can body flange together to form an intermediate peripheral seam; and compressing the intermediate peripheral seam against the upper portion of the chuck to form a double seam.