ピアノハンマのフェルトの動圧縮特性

抄録

Striking force, between a piano hammer and a string, was measured on a time axis. Furthermore, simultaneously measured was the displacements of the piano string and hammer-wood to obtain the compression-displacement of hammer felt from the difference between them. The compression-displacement of the felt is larger, at the time when the hammer is finally detached from the string, than the half of the compression-displacement maximal in a striking interval. The temporal variation of the virtual stiffness was obtained numerically from the compression-displacement and the striking force to result in the variation similar to that of the striking force. Because of this experimental result, assumptions on the stiffness in a striking interval, such that the stiffness is fixed or proportional to the square root of the displacement, do not reflect the reality.