Patent ID: 6992242

Claim:
A keyboard musical instrument comprising: a case defining an inner space open to an ambience through an opening, and having a fore-and-aft direction; a tone generating system partially housed in said case, and partially exposed to said ambience; a first board movably supported by said case, and extending over an area of said opening so that said opening is partially closed with said first board; a second board movably supported by said case independently of said first board, and changed between an open position and a closing position, said second board exposing said inner space to said ambience through a remaining area of said opening in said open position, said remaining area being closed with said second board in said closing position; and an automatic board spacer provided between said case and said first board, and changing said first board between a narrow gap position and a wide gap position when said second board is changed toward said open position, said automatic board spacer keeping said first board in said narrow gap position when said second board rests in said closing position for decreasing a gap between said first board and said second board, said automatic board spacer keeping said first board in said wide gap position after said second board leaves said closing position for increasing said gap.