| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a lid for an open duct to be easily workable and recyclable. SOLUTION: The lid 1 for covering the opening of an open duct is manufactured by aluminum die casting. A hold 234, into which a connecting strip 43 of a uniting member 4 is inserted, is formed by punching off a punching part 233 surrounded by a ring-shaped weak part 232.</p> |
