| 摘要 |
PURPOSE:To prevent noise generation by forming a rugged surface lining at least one one surface of a base plate for a door body. CONSTITUTION:A changeover door 1 of the inside and outside air consists of a base plate 9 of synthetic resin for a door body directly coupled with a rotationally movable shaft 8 and linings 10 on both sides of it. The lining 10 is made of soft polyurethane foam or urethane foam, and rugged parts 12 are formed on the surface. Degree of ruggedness is as large as near to the center part 12A, meanwhile the degree of ruggedness is a little smaller at the end part 12B. In such construction, when the end edge part 12B of the door 1 abuts on an end edge part 6 of the outside air intake side or an edge part 7 of the inside air intake side, at first top points of the projected part of the end part 12B contact on the edge part of air intake and then shift to surface contact as the door moves rotationally. Consequently noise generation such as a shock sound can be restrained. |
