BOTTOM STRUCTURE OF THIN CAN

PURPOSE:To improve resistance against pressure at a can bottom, making a can thin by a method wherein a shape of a dome-type cross section is formed by a curve whose curvature radius is almost continuously varied to eliminate sudden changing points. CONSTITUTION:If a cross section of a dome 1 is, for example, a part of an ellipse with a minor radius of (a)mm and a major radius of (b)mm, the curve expressing the shape of the cross section is a curve whose curvature radius (R1, R2, R3...Rn) is continuously varied, while there is no point where the curvature suddenly changes on junctions of the dome 1 and a counter 2 so that both are connected continuously with a smooth face. When a counter sink angle thetabetween a cross section of the counter 2 and a vertical line is 0 to 15 deg., a point where the curvature suddenly changes is not formed on the junction of the dome 1 and the counter 2.