| 摘要 |
<p>PURPOSE:To provide a keyboard supporting mechanism which has excellent dimensional stability to humidity and can be inexpensively constituted. CONSTITUTION:This keyboard supporting mechanism 4 is formed out of a key frame 6 and back rail 8 which are formed out of a medium-duty fiber board and on which a key 2 is freely oscillatably placed, a shelf board 10 which is formed out of a hollow metallic pipe having a square section and on which the key frame 6 and back rail 8 are placed and bolts 12 for fixing the key frame 6 and the back rail 8 to the shelf board 10. The metallic shelf board 10 is free from dimensional change by moisture absorption and, therefore, even if the key frame 6 and the back rail 8 are composed of the medium duty fiber board having a relatively large moisture-absorption thickness-expansion coefft., the fluctuation in the height of the keyboard 2 mounted at the reed 6 is suppressed down to about the same level as the fluctuation of the conventional device constituted of solid boards or plywood of the relatively small moisture- absorption thickness-expansion coefft. Since the inexpensive keyboard supporting mechanism is used, the inexpensive keyboard supporting mechanism 4 is constituted.</p> |
