摘要 |
The panel area is formed in the substantially rectangular shape with sides thereof which extend substantially straight, by being enclosed by the frame member and the vibration restraint portion to control a vibration area, such as beads and the bent line portion, and the high-rigidity area and the low-rigidity area are formed within the panel area. Accordingly, the vibration energy can be increased at the low-rigidity area properly. As a result, the vibration energy transmitted from the frame members to the floor panel can be reduced, and thereby the acoustic emission generated from the floor panel can be reduced.
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