| 摘要 |
PURPOSE:To increase active material holding ability by installing unevenness in a part of grid bones at the same time as expanding when a belt-shaped sheet of lead or lead alloy is expanded in a wide direction to form an expanded grid. CONSTITUTION:When a belt-shaped sheet of lead or lead alloy is expanded in a wide direction to form an expanded grid having rhombic grid cells 4, a punch and die for expanding are formed specific shapes and unevenness is formed in a part of grid bones 1 at the same time as expanding. Thereby, holding ability of active material 3 is readily increased without increase of grid thickness or the number of bones. Cost is reduced and coming off of active material is minimized. |
