CP-70/80 patent numbers

[Steven Kruyswijk]

Hi all,

I'm a Dutch Audio Design student (and parttime Rhodes technician)
currently graduating on the subject of the Yamaha CP series
electro-mechanical pianos.

For my research, I'd really like to read the patents about the
innovations in the CP pianos at www.uspto.gov, but a search there hasn't
been very productive. The online original manuals at
http://www2.yamaha.co.jp/manual/english/index.html weren't much help
either.

I know from experience with my Rhodes that patent numbers are often
printed inside the instrument. Could someone that owns a CP-70 or CP-80
please check their instrument if this is the case with theirs too? It
would help me a great deal.

Thanks in advance for your help,
Cheers, 

Steven Kruyswijk
stevenREMOVE@www2.hku.nl
http://www2.hku.nl/~steven/rhodes
http://www.audionerdz.com