The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 21, 2009
Filed:
Feb. 27, 2008
Tomoya Sasaki, Shizuoka-ken, JP;
Tomoya Sasaki, Shizuoka-ken, JP;
Yamaha Corporation, Shizuoka-Ken, JP;
Abstract
An automatic player piano is fabricated on the basis of an acoustic piano, and an automatic player is expected to give rise to key motion for reenacting performance with solenoid-operated key actuators; since the hammers of acoustic piano are different in mass, the load against the key motion is also different among the keys; while the motion controller is forcing the keys to travel on reference key trajectories through a servo control loop, the motion controller takes the pitched part into account, and selectively accesses control parameter tables so as to read out the approximate control parameters for the individual keys, whereby the hammers surely reach the target final hammer velocity before striking the strings.