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. 17, 2012
Filed:
Sep. 18, 2009
Mitsuru Kitajima, Hamamatsu, JP;
Hirotsugu Suzuki, Hamamatsu, JP;
Mitsuru Kitajima, Hamamatsu, JP;
Hirotsugu Suzuki, Hamamatsu, JP;
Yamaha Corporation, Hamamatsu-shi, JP;
Abstract
A keyboard apparatus having hammers each adapted for contact at its mass-unconcentrated half with a lower surface of an initial stopper that restricts initial pivot positions of the hammers, thereby reducing a contact force with which each hammer contacts the initial stopper, whereby the required thickness of the initial stopper can be reduced and height positions of key-depression surfaces of the keys in a non-key-depression state can be made uniform with ease. In the non-key-depression state, the hammers are in contact with the lower surface of the initial stopper mounted to a stopper mounting portion of the frame, whereby initial pivot positions of the hammers in a key-depression forward stroke are restricted and key-depression initial positions of respective keys are indirectly restricted, so that the height positions of key-depression surfaces of the keys are made uniform.