Abstract: A hammer device of an electronic piano with keys which swing in accordance with key depression, includes a hammer support that is made of a synthetic resin and has a fulcrum shaft, and a hammer having a shaft hole part for being fitted on the fulcrum shaft and configured to pivotally move about the fulcrum shaft in a manner interlocked with the swinging key. The fulcrum shaft has an outer peripheral surface formed by a pair of arcuately-curved surface portions opposite to each other and a pair of planar surface portions each extending between the pair of arcuately-curved surface portions and parallel to each other.

Abstract: A bat for an upright piano is provided for ensuring stable swinging movements of a hammer to generate a proper piano sound even if a hammer assembly has the centroid which is laterally asymmetric about a center pin. The bat for an upright piano is supported by the center pin having a circular cross section and arranged horizontally in a bat flange, in order to swing a hammer to cause the same to strike a string. The bat comprises a bat body integrally formed with the hammer, and having a linear pin holding groove in a back surface thereof, and a metal plate having a linear pin retaining groove in one side thereof, and attached to a back surface of the bat body such that the pin retaining groove extends in parallel with the pin holding groove, wherein the bat is pivotally supported by the center pin while the center pin is in engagement with the pin holding groove and the pin retaining groove, and the center pin is sandwiched between the bat body and the metal plate.

Abstract: There is provided an electric keyboard assembly having a construction which is capable of reducing a height of a keyboard and at the same time facilitating key scaling to key-touch response while maintaining the degree of freedom in designing the keyboard. A key is pivotally moved by a key depressing operation. A seesaw-type mass member having a front extension and a rear extension each extending from a pivot-receiving portion thereof, and a tone-generating position adjustment screw fitted in the front extension is pivotally moved about the pivot-receiving portion by a driving force generated by depression of the key and received via the tone-generating position adjustment screw. The front extension of the mass member pops up to a level higher than the key when the key is depressed. A front weight and a back weight are arranged separately in the front extension and in the rear extension, respectively.

Abstract: A universal piano action having a minimum number of identical parts interchangeable in upright and grand pianos, under and above the tensioned strings and effecting rapid repetition in upright and grand pianos, this universal piano action responds to every strenght of touch evoking sounds from a whisper to thunder. In this universal piano action the hammers can be positioned to any at rest position, to any proximity in respect to the tensioned strings for a sensitive control of sound, permitting practice playing with a normal strenght of piano key touch without disturbing.

Abstract: A piano keyboard apparatus has an action assembly that includes a four bar linkage having four pivotably connected bars including a whippen pivotably connected to a repetition lever. An articulated jack has a lower link pivotably connected to an upper link and the lower link is pivotably connected to the whippen.