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:
Aug. 03, 1999
Filed:
May. 16, 1996
Shinji Kumano, Shizuoka-ken, JP;
Tsuyoshi Sato, Shizuoka-ken, JP;
Yamaha Corporation, Hamamatsu, JP;
Abstract
A keyboard apparatus has a support member and a plurality of white keys and black keys. Each of the white keys and the black keys has a fulcrum section and a driving section, and are pivotally mounted about the fulcrum section with respect to the support member. A mass body assembly, that is an action member, has a moving fulcrum, a driven section on a first side of the moving fulcrum that is driven by each of the driving sections of the white keys and the black keys, and a center of gravity that is located on a second side opposite the driven section with respect to the moving fulcrum. The distance between the driven section and the moving fulcrum of the mass body assembly for the black key is greater than the corresponding distance for the white key. The mass body assembly on the second side is formed from the same members that are commonly used for both the white keys and the black keys.