| 摘要 |
PROBLEM TO BE SOLVED: To prevent the forward fall down of a piano at the time of an earthquake with simple and inexpensive constitution without requiring work of walls, etc., at all by mounting a cushion for weakening repulsion when a piano body inclines to the rear surface of a piano body and comes into contact with a rear wall. SOLUTION: This preventive device 12 comprises the cushion 13 mounted on the rear surface of the piano body 10. The cushion 13 comprises an intimately mixed foam of, for example, hydrophobic urethane and a bituminous substance. The viscoelasticity of this intimately mixed foam has the characteristic that the deformation when external force acts and the restoration of the original shape after the deformation does not instantaneously take place and requires some time; therefore the foam has a high buffer ability. The cushion 13 is adhered to cover the cross-beam lining extending laterally in the upper part of the rear surface of the piano body 10. In the event of the occurrence of the earthquake, the piano body 10 first inclines backward and the cushion 13 comes into contact with the wall. At this time, the impact load on the wall is well absorbed by the cushion 13. |
