Title: Transducer free from aged deterioration, musical instrument using the same and method used therein
Application Number: 200510099534 Application Date: 2005.09.13
Publication Number: 1750111 Publication Date: 2006.03.22
Approval Pub. Date: Granted Pub. Date:
International Classifi-cation: G10F1/02;G10H1/00
Applicant(s) Name: Yamaha Corp. Address:
Inventor(s) Name: Sasaki Tsutomu
Attorney & Agent: di wankui huang xiaolin
Abstract:
    An electronic system, which serves as a recorder and an automatic player, is installed in an automatic player piano, and hammer sensors, which are implemented by photo couplers, report current hammer positions through analog signals to a data processor so that the data processor analyzes pieces of hammer data for recording the performance in a set of music codes; the analog signals are amplified through an operational amplifier and, thereafter, converted to discrete values of digital hammer signals so that an offset voltage is unavoidably introduced into the analog signals; when the photo couplers vary the light-to-photocurrent converting characteristics due to the aged deterioration, the data processor takes the offset voltage into account, and calibrates the hammer sensors, thereby making the digital hammer signals correctly express the current hammer positions.
Time: 6