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:
Oct. 07, 2008
Filed:
Jan. 25, 2006
Kenichi Hirota, Shizuoka-ken, JP;
Tetsuya Hirano, Shizuoka-ken, JP;
Kenichi Hirota, Shizuoka-ken, JP;
Tetsuya Hirano, Shizuoka-ken, JP;
Kabushiki Kaisha Kawai Gakki Seisakusho, Shizuoka-ken, JP;
Abstract
A speed detecting apparatus for a keyboard musical instrument is provided for accurately detecting the speed of bivotal movements of a hammer and a key even if a shutter implies errors in its attachment, without affected by such errors. The speed detecting apparatus for a keyboard musical instrument comprises a pivotable key, a hammer pivotably supported by a fulcrum and configured to pivotally move in association with a pivotal movement of the key, a shutter integrally attached to the hammer, a plurality of detectors, each having a light emitter and a light receiver for receiving light emitted from the light emitter, arranged on one and the other sides of the pivotal movement path of the shutter, and a CPU for detecting a pivot speed of the hammer in response to timings at which the shutter opens and closes the light paths of the light of the plurality of detectors when the hammer pivotally moves. The plurality of detectors have detection points on respective light paths of the light from the light emitters, and are arranged such that the detection points are positioned on an arc centered at the fulcrum of the hammer.