Yamaha Corporation

Satoshi Inoue

Hajime Hayashida

Tomonori Ichikawa

Noboru Yamashita

Hitoshi Izutani

Kiyoshi Kawamura

Takashi Aoyagi

Yasuhiko Oba

Masahiro Wada

Shigeaki Sato

Toshiaki Sakai

Toshio Yamayoshi

Hiroshi Umeji

Yoshinori Suzuki

Ringi Nozue

Keys of a piano are depressed against the total weight of associated action units and hammers so that balance weight pieces are embedded in the front portion of each key; since the wood bar of the key is expandable and shrinkable due to the conditions of the environment, the weight pieces are liable to come loose; the balance weight piece is formed with ridges and valleys repeated at least 7 times at fine pitches equal to or less than 2 millimeters, and the maximum diameter of the ridges is slightly longer than an inner diameter of a hole formed in the wood bar; while the balance weight piece is being pressed into the hole, the ridges make the inner surface portion elastically deformed; when the balance weight piece reaches the target position, the inner surface portion penetrates into the valleys so that the balance weight piece is lodged therein.

Movable part firmly equipped with balance weight, musical instrument and method of assembling balance weight therein

An upright piano includes action units between keys and hammers, and the action units are less prompt so that a missing tone tends to take place in a music passage through high-speed repetition; the action unit is constructed from a whippen assembly, a jack mechanism provided on the whippen assembly and a regulating button mechanism for an escape in cooperation with the jack mechanism, and a compression coil spring is provided between a center rail and the whippen assembly for urging the whippen assembly in a direction toward the original position, thereby accelerating the restoration of jack to the contact with the hammer.

Upright piano and action unit incorporated therein

A grand piano has action units for driving hammers to rotate toward strings, and each action unit is equipped with a repetition mechanism; the repetition mechanism has an elastic guide plate instead of a repetition lever and a repetition spring; and the elastic guide plate per se is deformed after contact with a drop screw, and returns to the initial position for permitting a pianist to play a music tune through repetition of key when the pianist releases the depressed key, whereby the action unit becomes simpler in structure than the conventional action unit.

Keyboard musical instrument and action unit incorporated therein

Keys of an acoustic piano require balancers for cancellation of a part of self weight of the action units/hammers; however, the balancers are liable to be dropped off due to the aged deterioration of the wooden bars; in order to keep the balancers stable in the keys against the aged deterioration, the balancer is plastically deformed so as to bite into the wooden bar, the balancer, which is formed with thorns, is rotated so as to make the thorns bite into the wooden bar, the balancer is shaped into a configuration different from the holes so as to exert resilient force on the inner surface in a direction in parallel to the grain of wood, or the balancer is inserted into a constricted hole so as to strongly exert the resilient force on the inner surface, thereby being prevented from the dropping off from the keys.

Keyboard musical instrument having keys equipped with balancers biting into keys and method for securing balancers to keys

A front board, side boards and a rear board define the periphery of a cabinet for a keyboard musical instrument; a top board is connected to the front board through a mortise and tenon joint, and is further coupled to rear posts by means of an angle bar and bolts; the tenon is easily inserted into the mortise so as to make the assembling work easy and speedy.

Keyboard musical instrument having top board coupled with another board through mortise and tenon joint

A plurality of strings are stretched over a frame, constituting an overall framework of a body of a piano, with their respective rear-end engaging rings engaged by corresponding pins provided on the frame. There is also provided a string-bounding preventing member that, in case any one of the strings snaps or breaks, prevents the broken string from disengaging from the corresponding pin to bound violently away from the pin. The string-bounding preventing member is, for example, a strap member that is passed through the respective engaging rings to thereby connect together the strings. The string-bounding preventing member allows the broken string to be left connected with the other strings and hence stay in place on the frame without bounding.

String-bounding preventing structure for piano

A key is an indispensable component parts of an acoustic or electronic keyboard musical instrument, and key balancers are embedded in the key for varying the moment exerted on the key; the key balancers are fastened to the key by means of an anchor so that the key balancers are neither chattered in nor dropped out from the key.

Keyboard musical instrument having keys regulated with stable key balance pieces and process for fabricating keys

Keyboard musical instrument having keys regulated with stable key balance pieces

A grand piano has a built-in music rack for keeping a music score book thereon, and the built-in music rack includes a guide laterally extending inside the piano cabinet and a desk board projecting over the piano cabinet and connected to the guide; when a pianist exerts force on the desk board, the guide permits the desk board to slide laterally so that the pianist can easily adjust the music score book to a proper position; since most of the guide is hidden inside the piano cabinet, the pianist feels the grand piano same in external appearance as a standard grand piano.

Keyboard musical instrument with laterally adjustable built-in music rack and music rack used therein

A silent piano is a composite keyboard musical instrument fabricated on the basis of an acoustic piano, and a pianist plays a tune by piano tones or electronic tones; when the pianist selects the electronic tones, a hammer stopper enters the trajectories of hammers, and a tandem regulating button mechanism changes damping columns onto the trajectories of jacks in such a manner that the jack is brought into contact with the damping column concurrently with a regulating button; since the damping columns are closer to the jack than the regulating buttons, the jack turns at a larger angular velocity so that the hammer is not pinched between the jack and the hammer stopper; the damping columns are moved onto a virtual plane where the regulating buttons are so that the jacks are commonly used between the silent piano and the standard acoustic piano.

Composite keyboard musical instrument, silent system for performance without acoustic tones and regulating button mechanism for changing escape timing depending upon mode of operation

A grand piano have a keyboard implemented by white and black keys selectively depressed by a player for specifying the notes of tones to be generated, and action units are linked with the white and black keys so as to give rise to free rotation of associated hammers through escape, wherein a key-touch regulator is provided between the key frame and the white and black keys for partially canceling the moment initially exerted on the white and black keys due to the self-weight of the action units and the hammers so that any lead weights is not required for regulating the key-touch.

Keyboard musical instrument equipped with key-touch regulator provided between keys and stationery member

A silent piano includes a hammer stopper changed between a free position out of the trajectories of hammer shanks and a blocking position on the trajectories for blocking strings from being struck with the hammers and a tandem regulating button mechanism having standard regulating buttons and regulating bars used together with the hammer stopper changed in the blocking position for changing escaping speed of jacks, and an adjusting mechanism is provided between the regulating bars and a shaft for adjusting the regulating bars to appropriate angular positions, wherein the adjusting mechanism has regulating screws projecting from stationary brackets fixed to the shaft into a free space created in front of the array of action mechanisms so that a tuner easily adjusts the regulating bars to the appropriate angular positions without removing the action mechanisms from on the key bed.

Regulating button mechanism for easily regulating escape timing, silent system cooperative therewith and keyboard musical instrument equipped therewith

A keyboard musical instrument is a combination of an acoustic upright piano without strings and an electronic tone generating system, and a hammer receiver is beaten with hammers respectively linked with key action mechanisms, wherein the each of the hammers has a hammer shank fixed to a butt of the key action mechanism and a weight member attached to the hammer shank, and the weight member has a center of gravity in the vicinity of the center of gravity in a hammer head of a regular hammer usually incorporated in the standard upright piano so that the key touch is identical with or similar to that of the piano key touch.

Keyboard musical instrument having dummy hammer with well-regulated center of gravity for producing piano-like key touch without acoustic sound

A keyboard musical instrument includes a keyboard, key action mechanisms and hammer assemblies as similar to an acoustic piano; however, strings are replaced with a beaten member so that a player practices a fingering on the keyboard without an acoustic sound; each of the hammer assemblies has a cylindrical hammer head formed of metal or synthetic rubber/synthetic resin, and no twisting moment is exerted on the hammer shank regardless of relative angular position between the hammer head and the hammer shank.

Growing community of inventors

Shizuoka-ken, Japan

Satoshi Inoue