| 摘要 |
<p>PURPOSE:To make a whole device thin by arranging a hammer arm for a black key in the under space of a white key between the front edge of the black key and the front edge of the white key to be arranged adjacently to the side of this black key. CONSTITUTION:An under space 50 is formed under two white keys 10 between a front plate 19 of a black key 11 and a front plate 43 of the two white keys 10 arranged adjacently to both side of the black key (accurately to say, two white key guide parts 45), and in the under space 50, a hammer arm 51 for the black key is arranged. And both shaft parts 52 of the hammer arm 51 are inserted into the black key 11 through a notched part 54 formed under the front plate 19 of the black key 11, and attached rotatably to bearing parts 55 formed at opposite prescribed positions under both side plates 18 at the front edge of the black key 11 through bearings 56 respectively. Thus, regarding the black key 11 especially, it is possible to thin the whole device, and the number of part can be reduced.</p> |
