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. 16, 2012
Filed:
Jun. 25, 2010
Nariyasu Yaguchi, Hamamatsu, JP;
Akihiko Komatsu, Hamamatsu, JP;
Yoshinori Hayashi, Iwata, JP;
Yamaha Corporation, , JP;
Abstract
In a keyboard apparatus including a key supported for pivoting movement about a pivot point, a mass member that imparts a reaction force to performance operation of the key in interlocked relation to the key, and an electromagnetic actuator provided between the key and the mass member for imparting a driving force to the key and mass member, a transmission member is provided in detachable abutment with the key and mass member. The transmission member can be disengaged from the key or the mass member depending on operating conditions of the key and the mass member. Thus, it is possible to not only prevent unnecessary binding forces from acting in areas where the transmission member and the key and the mass member abut against each other, but also achieve smooth movement of the key and the mass member and prevent increase of inertial mass of the transmission member. The smooth movement of the key and mass member can achieve force sense control with good responsiveness. Further, the key is pivotable in a key depressing direction as a reaction force imparted from the mass member is reduced by impartment, to the key, of a driving force by the actuator. Thus, the apparatus can perform both force sense control on depression operation of the key and an automatic performance involving automatic operation of the key, through cooperation between a reaction force imparted from the mass member to the key and the driving force imparted from the actuator to the key.