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:
Nov. 14, 2000
Filed:
Mar. 30, 1999
Shinji Kumano, Hamamatsu, JP;
Yamaha Corporation, Hamamatsu, JP;
Abstract
A keyboard assembly for a keyboard instrument such as an electronic piano is constructed using a key, a first moving member, a second moving member and a key-depression switch. Herein, the key is supported by a keyboard frame to have a capability of rotating up and down about a rotation center. The first moving member is arranged beneath the key and is subjected to rotary motion about a first rotation center. The second moving member incorporating a deadweight has a larger weight and a longer moving distance as compared with the key and first moving member respectively. At the key depression, mode a back portion of the first moving member rotates upwardly so that the second moving member normally located at a rest position is subjected to rotary motion about a second rotation center. Thus, the second moving member rotates backwardly, and, it is stopped at a contact position defined by a back portion of the keyboard frame. Thereafter, the second moving member is subjected to back checking by which the second moving member is slightly moved forward and is temporarily fixed in position as long as the depression of the key is maintained. The key-depression switch is located beneath the key and is turned on to produce a musical tone in response to the depression of the key.