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:
Feb. 17, 1998
Filed:
Oct. 12, 1995
Takamichi Masubuchi, Shizuoka-ken, JP;
Toshiyuki Iwamoto, Shizuoka-ken, JP;
Yamaha Corporation, Hamamatsu, JP;
Abstract
A keyboard apparatus for an electronic musical instrument includes a key displacement detection unit. The key displacement detection unit includes a first resilient member, a movable member connected to the first resilient member, a second resilient member connected to the movable member, and a base fixing member connected to the second resilient member. The base fixing member may be directly or indirectly fixed to a keyboard musical instrument so that the key displacement detection unit is mounted to the keyboard musical instrument. A first displacement detection sensor is coupled with the first resilient member for detecting a key depression force in a key depression-release direction, and a second displacement detection sensor is coupled with the second resilient member for detecting a key depression force in a key arrangement direction. Both the first displacement detection sensor and the second displacement sensor are mounted on the key displacement detection unit. The first resilient member and the second resilient member are connected to the movable member in a folded manner. As a result, the key displacement detection unit becomes small in size and yet provides a relatively large displacement in the first and the second resilient members with a relatively small key depression force.