| 摘要 |
<p>PROBLEM TO BE SOLVED: To enable a weight to display the same function with lead by easily and securely fitting the weight to the keyboard by fitting a weight, which is formed of metal with large specific gravity other than lead in a truncated cone shape, in a weight through hole formed of a tapered hole in the flank of the keyboard at a specific place. SOLUTION: The keyboard 1 has the weight through hole 2 formed in a tapered shape and opened in both the flanks and the weight 11 is fitted in the weight through hole 2. At this time, the center of gravity of the keyboard 1 shifts from the breadthwise center to a small-diameter side because of the tapered hole, so the taper of the weight through hole 2 is preferably small. The weight 11 is formed of metal which has large specific gravity and is no harmful other than lead, e.g. iron, brass, and sintered metal. This weight 11 is easily fitted in the weight through hole 2 by being formed in a truncated cone shape having nearly the same taper with the weight through hole 2 and is fixed through wedge operation. Therefore, the weight need not be pressed in, so the keyboard 1 is prevented from cracking and fixation using an adhesive is unnecessary.</p> |
