| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for obtaining a pressed product that is free from sink marks even on its thin-walled portion and has thick flat plate parts with enough flatness, even by means of a commonly-used mechanical press. <P>SOLUTION: The pressed product 1 is manufactured from a flat steel plate as a starting material. The pressed product 1 has punched holes 11 and 12 in a platy body 10. The wall thickness t between the inner circumferential faces 110 and 120 of the punched holes 11 and 12, and the outer wall face of the body 10 is equal to or less than the plate thickness in the thinnest-walled portion Z, and the body 10 including the thinnest-walled portion has flatness of 0.2 mm or less. The pressed product 1 is manufactured through a punching step (i), a preliminary hole boring step (ii), a coining step (iii) and a finishing step (iv) in sequence. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
