{
  "$type": "site.standard.document",
  "description": "A battery case (1) is formed such that a thickness (t1) of a side wall (1a) with respect to a thickness (t0) of a bottom wall (1b satisfies t1 = alpha t0 ( alpha = 0.2 to 0.7) by undergoing an ironing step using ironing dies (11, 12, and 13) aligned in multiple stages, and that an inside face of…",
  "path": "/patents/1098240",
  "publishedAt": "2003-02-26T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "B21D22/28",
    "MATSUSHITA ELECTRIC INDUSTRIAL CO LTD [JP]"
  ],
  "textContent": "A battery case (1) is formed such that a thickness (t1) of a side wall (1a) with respect to a thickness (t0) of a bottom wall (1b satisfies t1 = alpha t0 ( alpha = 0.2 to 0.7) by undergoing an ironing step using ironing dies (11, 12, and 13) aligned in multiple stages, and that an inside face of the side wall is made to have a rough surface having average surface roughness of 0.2 mu m to 2.0 mu m by undergoing a drawing step after the ironing step. A manufacturing method of the battery case includes a first step of manufacturing a battery case element (7) by applying the DI processing to a cup-shaped intermediate product (4), and a second step of manufacturing a battery case by reducing an outside diameter to a predetermined outside diameter (r) without changing a thickness of a side wall by applying drawing processing to the battery case element by drawing dies (18 and 19) aligned in multiple stages.",
  "title": "CELL TUBE AND METHOD OF MANUFACTURING THE CELL TUBE"
}