| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a battery case and a blank therefore which enable subjecting a battery case made of a hard and thin-wall steel plate to deep- drawing, and a manufacturing method for the battery case. SOLUTION: The battery case is configured to be a deep-drawing product made of a steel plate with no seamless in such a manner that the length is six or more times of the width and the depth is five or more times of the width. As for the blank for the battery case, an external appearance of the blank for the deep-drawing is formed like an oval, and at an outer circumference portion of the blank and a position symmetric with respect to a major axis of the approximate oval shape, a plurality of protrusions projected externally from the circumference portion of the approximate oval shape are formed into one. A manufacturing method for the battery case is carried out employing the blank for the battery case as described in claims, where the circumference portion of the approximate oval shape having the projected protrusions are slidably pressed, to conduct deep-drawing of multi-stages.</p> |
