| 摘要 |
PURPOSE:To make acoustic characteristics excellent by structuring a housing so that a sound is substantially sealed up and preventing a sound emitted from the back side of a speaker from interfering with a sound emitted from the front side of the speaker. CONSTITUTION:When a white key 28 or black key 29 is pressed down, a projection 35 while guided by a key guide 19 enters a recessed part 45 partitioned with the subordinate body 15 of a keyboard chassis 3 and the intermediate wall 12 of the front side part 6 of an upper case 4. Then the lower ends of both side walls of the white key 28 or black key 29 abut on a stopper 36 on the top surface and are held at lower-limit positions, and an actuator 40 closes a key switch 39, so that a sound is emitted from the speaker 41. At this time, the sound emitted from the front side of the speaker 41 exits from the housing 1 through the top surface wall 43 of the rear side part 7 of the upper case 7, but the sound emitted from the back side of the speaker 41 is substantially sealed up by the housing 1, so the sound never exits outside the housing 1. Therefore, the sound from the back side of the speaker never interfere with the sound from the front side of the speaker. |
