Yamaha Corporation

Nippon Gakki Seizo Kabushiki Kaisha

Keisuke Watanabe

Junichi Mishima

Shigeru Muramatsu

Ichiro Osuga

Takamichi Masubuchi

Tsuyoshi Sato

Toshiyuki Iwamoto

Masao Kondo

Shinji Kumano

Yoshimasa Yoshikawa

Susumu Ohi

Key is pivotably supported by a key frame, and the front end of the key is normally urged upward by a pivot lever. Load member drivable by an actuator is provided rearwardly of a mass body of the pivot lever. Key switch and proximity sensor detect a pivoting position of the key responsive to depression and release operation of the key. Load control circuit performs driving control of the actuator, in accordance with the pivoting position of the key, to move the load member back and forth, to thereby cause the load member to engage (or contact) with the mass body in a depression stroke and terminates the engagement in a release stroke.

Electronic musical instrument keyboard apparatus

Keyboard apparatus has a frame and a key pivotably mounted on the frame. Key guide structure includes a key-side guide member provided inside the key, and a frame-side guide member provided on the frame. The key-side guide member has at least one convexly-formed portion projecting from the inner surface of a distal end portion of the key, remote from a pivot point of the key, toward the pivot point. The frame-side guide member permits movement of the key-side guide member along a pivoting direction of the key, but limits lateral movement of the key-side guide member.

Key guide structure in keyboard apparatus

A keyboard apparatus constructed to be capable of reducing the depth size thereof and permitting a key unit to be mounted to a key frame with a simple operation. Hinges are extended downward from rear ends of black key main bodies of a black key unit in the vertical direction, and are connected at their lower ends to a common-to-black-keys base end. The black key main bodies are pivotable via the hinges relative to the common-to-black-keys base end in the key depression/release direction. Similarly, white key main bodies of first and second white key units are pivotable via hinges relative to a common base end in the vertical direction. The key frame is formed at its rear portion with a recessed groove over the entire width of all keys and formed with elastic members extending in the front-to-rear direction on the front and rear sides of the recessed groove. Using elastic deformations of the elastic members, a common-to-all-keys base end of the key unit is fitted and fixed to the recessed groove.

Keyboard apparatus

A keyboard assembly for an electronic musical instrument comprises at least a plurality of keys, a key support member and a plurality of key-return springs. The key support member rotatably supports the keys; and the key-return spring is provided between the key and key support member so as to press up the key to a normal position. Mechanical parameters which affect a key scaling to key-touch responses of the keys are sizes, shapes and locations of parts of the keyboard assembly, which are set by analyzing motions of an action mechanism of an acoustic piano. For example, weight of the key is adjusted using a deadweight member so as to provide a specific key-touch response for the key. An amount of elastic resilience, made by the key-return spring, is adjusted by changing at least one location, at which one end of the key-return spring is terminated, so as to provide a specific key-touch response for the key. Viscous resistance, made by viscous material, such as grease, which is provided between a selected portion of the key and some member, such as a key guide and a support-point member, is adjusted by changing shape and/or size of that member, so as to provide a specific key-touch response for the key. The key scaling is performed by changing the key-touch response with respect to each of the keys; or the key scaling is performed by changing the key-touch response with respect to a selected division of the keyboard.

Electronic musical instrument simulating acoustic piano keytouch

Keyboard assembly for electronic musical instrument

A key for keyboard instruments includes a molded key body and a perspiration-absorbing sheet. The molded key body is pivotally secured to a supporting member of the instrument and formed of a synthetic resin. The perspiration-absorbing sheet is provided over the surface of the key body so that the perspiration-absorbing sheet serves as a top, playing surface of the key.

Key for keyboard instrument having a perspiration-absorbing surface

A keyboard unit for an electronic musical instrument is constructed by a plurality of keys, a key frame, a plurality of key guides and a pressure sensor. On the key frame, a plurality of keys are arranged such that each of them can freely rotate about the predetermined fulcrum point. The key guides are provided on the key frame, while each of the key guides supports each of the keys such that each of the keys can slide along guide surfaces of each of the key guides when the key is depressed. The pressure sensor is provided at the guide surface of the key guide. This pressure sensor senses the pressure applied thereto in a lateral direction corresponding to a disposing direction of the keys in the keyboard unit when the key is depressed. When the key is moved in the lateral direction while being depressed down, the pressure sensor senses the pressure applied to the key in the lateral direction so that the predetermined musical parameter (e.g., tone pitch) of the musical tone to be generated is controlled responsive to the sensed pressure. The pressure sensor can be made by use of the pressure-sensitive rubber or pressure-sensitive ink, of which resistance is altered responsive to the pressure applied to it.

Keyboard unit for electronic musical instrument having a key motion

In construction of a keyboard apparatus in which a plurality of keys are swingably mounted to a fixed key support and change in electric inductance is induced in response to every key operation for adjustment of musical tone control parameters, the change in inductance by an inductance change inducer is detected by at least one planar coil pattern which is arranged such that its mating surface area with the an inductance change inducer should change in correspondence to the key stroke of the key at key operation. Thanks to use of the change in the mating surface area in detection, a linear relationship is obtained between the key stroke and the detection output, which well avoids inter-key variation in detection output for uniform generation of musical tones from different keys.

Musical tone central parameter controller for a musical instrument

In construction of an electronic musical instrument having plural musical tone controllers such as keys, push buttons and an expression pedal unit, a number of pulses are generated depending on the extent of movement of each controller on output lines whose number is smaller than that of the pulses so generated and musical tone control parameters such as tone volume, tone color and tonal pitch are changed in multi-stage fashion in response to the pulses generated. Generation of musical tones is assured whilst well reflecting delicate change in player's emotion via subtle key touch control.

Touch-response tone controller unit for an electronic musical instrument

A touch response device for an electronic musical instrument includes pressure detector for detecting initial-touch and after-touch of a key. The pressure detector means has two or more response stages that have different response characteristics to key pressure variation. An initial-touch-detector signal is produced when the pressure detecting means is in a first response stage among the response stages, and after-touch-detector signal is produced when the pressure detecting means is in a second response stage among the response stages. According to the invention, initial-touch signal and after-touch signal are generated by the use of one common operation-detector signal produced from the pressure detector means. As a result, the construction of the pressure detecting means is much simplified compared with a conventional touch-response device provided with two separate detectors, one of which detects initial-touch and another of which detects after-touch.

Touch response device for electronic musical instrument

A keyboard apparatus of an electronic musical instrument includes keys, mass members, and springs. Each key can pivot about a first pivot fulcrum. Each mass member can pivot about a second pivot fulcrum. Each spring supplies a biasing force to at least the corresponding mass member so that the mass member returns to an initial state. In this apparatus, each key has a point of application for pivoting the corresponding mass member in the same direction as a pivoting direction of each key when each key is depressed.

Keyboard apparatus of electronic musical instrument

There is disclosed a keyboard structure incorporated in an electronic keyboard instrument the keyboard structure including; a plurality of key members each having a depressible front end portion and a rear end portion; a plurality of flexible connecting members each merged with the rear end portion of each key member; a retainer member merged with the flexible connecting members for retaining a circuit board which carries a plurality of key switches; and a plurality of coupling members each having a first element merged with the rear end portion of each key member and a second element merged with the retainer member, and the first element is snapped into the second element, so that major members are simultaneously formed by a molding, thereby enhancing the assembling efficiency.

Structure of keyboard used in electronic keyboard instrument

A keyboard switch apparatus for an electronic musical instrument has first, second and third layers, and first and second switches. The second layer has elasticity and is separated from the first layer. The third layer has elasticity and is inserted between the first and second layers at a distance therefrom. The first switch consists of conductors respectively formed on opposite surfaces of the second and third layers. The second switch consists of conductors respectively formed on opposite surfaces of the first and third layers. The second and third layers are sequentially urged and deformed by an actuator interlocked with key depression. The first and second switches are sequentially closed. A time requred for closing the first switch is different from that for closing the second switch. The closure time difference corresponds to a key depression speed, which is used to generate a signal corresponding to the depression speed, and a musical tone signal corresponding to the depression speed.

Keyboard switch apparatus for electronic musical instrument

A keyboard switch apparatus for an electronic musical instrument has first and second switches each constituted by stationary and movable contacts. The stationary contacts of the first and second switches are formed adjacent to each other on a single board. The movable contacts of the first and second switches are mounted on a single flexible member arranged above the single board and are normally spaced apart from the stationary contacts at positions opposite thereto. The flexible member and the movable contacts of the first and second switches are integrally formed to have a uniform cross-sectional shape along one direction. The flexible member is deformed in response to the depression of a key. The stationary contacts corresponding to the movable contacts of the first and second switches are closed with a time difference according to a speed of key depression.

A pedal keyboard for an electronic musical instrument, includes a pedal key vertically pivotal about a pivot mechanism mounted on a frame of a housing for the electronic musical instrument, a spring for biasing the pedal key so as to cause the pedal key to return to an initial position, and a stopper for limiting pivotal movement of the pedal key. The spring is arranged behind the pivot mechanism of the pedal key, and the stopper is arranged behind the spring, thereby improving key depression feeling and forming a gap in the pivot mechanism to achieve smooth pivotal movement of the key.

Growing community of inventors

Hamamatsu, Japan

Keisuke Watanabe