Flat elliptical battery case can having an annular groove to support a sealing plate, a method and an apparatus for manufacture of the same

摘要

To present a processing apparatus capable of forming an annular support portion for mounting a sealing plate on an elliptical battery case can at high precision and high productivity, and a structure of an elliptical battery using an elliptical battery case can. An elliptical battery case can 10 is rotatably held by a case can support mechanism 13. The battery case can 10 is rotated about its tubular center by a case can rotary mechanism 18. Two groove forming rollers 23, 24 are mounted on an oscillatable roller support lever 28. The roller support lever 28 traces the shape of the outer circumference of the battery case can 10, and oscillates within a plane orthogonal to the tubular center of the battery case can 10, and receives a pressing force from a pressurizing device 29 to press the both groove forming rollers 23, 24 against the outer circumference of the battery case can 10. As a result, an annular groove 50 is formed in the outer circumference of the elliptical battery case can 10, and an annular support portion 40 is formed in the inner circumference.