Abstract: A keyboard assembly for a keyboard instrument such as an electronic piano is constructed using a key, a first moving member, a second moving member and a key-depression switch. Herein, the key is supported by a keyboard frame to have a capability of rotating up and down about a rotation center. The first moving member is arranged beneath the key and is subjected to rotary motion about a first rotation center. The second moving member incorporating a deadweight has a larger weight and a longer moving distance as compared with the key and first moving member respectively. At the key depression, mode a back portion of the first moving member rotates upwardly so that the second moving member normally located at a rest position is subjected to rotary motion about a second rotation center. Thus, the second moving member rotates backwardly, and, it is stopped at a contact position defined by a back portion of the keyboard frame.

Abstract: A mounting construction of an elongated leaf spring deformed in an S-letter configuration and engaged at opposite ends thereof with a pair of spaced support members in a compressed condition to effect outward biasing forces acting of the support members, wherein three nodes are formed at the opposite ends and an intermediate position of the leaf spring in a longitudinal direction to form a pair of antinodes between the opposite ends and intermediate position of the leaf spring.

Abstract: A keyboard apparatus has a support member and a plurality of white keys and black keys. Each of the white keys and the black keys has a fulcrum section and a driving section, and are pivotally mounted about the fulcrum section with respect to the support member. A mass body assembly, that is an action member, has a moving fulcrum, a driven section on a first side of the moving fulcrum that is driven by each of the driving sections of the white keys and the black keys, and a center of gravity that is located on a second side opposite the driven section with respect to the moving fulcrum. The distance between the driven section and the moving fulcrum of the mass body assembly for the black key is greater than the corresponding distance for the white key. The mass body assembly on the second side is formed from the same members that are commonly used for both the white keys and the black keys.

Abstract: A keyboard apparatus having keys and mass members that are relatively light in weight and low in cost and yet provide a good key touch feeling that is comparable to the key touch feeling of a keyboard apparatus of an acoustic grand piano. A keyboard apparatus for an electronic musical instrument includes a support member including a first fulcrum section and a second fulcrum section. A key is movably supported about the first fulcrum section of the support member, and a mass member is movably supported on the support member and coupled to the key. The mass member has a mass concentration section made of an elongated metal bar and a resin section connected to the mass concentration section. The resin section has a pivotal fulcrum receiving section to be pivotally supported about the second fulcrum of the support member.

Abstract: A keyboard apparatus for a musical instrument which includes a laterally elongated frame structure made of synthetic resin, a plurality of keys arranged in parallel on the frame structure and pivoted at their proximal ends on a rear end portion of the frame structure to be depressed at their front portions, and a laterally elongated printed circuit board mounted on the frame structure and provided thereon with a plurality of detection switches which are arranged to detect depression of the keys.

Abstract: A keyboard apparatus has a first frame (support member), and a keyboard including a plurality of white keys and black keys, each of the keys having a fulcrum and movably about the fulcrum with respect to the support member. Each of the black keys has an extension section connected to one end of each of the black keys. The extension section extends under operation sections of two adjacent white keys toward the free ends of the white keys. A white key driving section is provided adjacent to a free end portion of each of the white keys. A black key driving section is provided adjacent to a free end portion of each of the extension sections. The white key driving sections and the black key driving sections are located at substantially the same distance from their respective fulcrums, and drive movable sections such as mass body assemblies (action members) or key switches that are operated in association with the corresponding white keys and the black keys.

Abstract: A keyboard apparatus is constructed on a frame having a plurality of support members. A plurality of keys are movably supported by the corresponding support members such that each key can be operated by a finger action to undergo a primary stroke movement. A plurality of mass members are disposed in the frame. Each mass member is linked to a corresponding key for undergoing a secondary stroke movement in response to the primary stroke movement of the corresponding key so as to impart a dynamic reaction to the finger action. A stopper member is disposed in the frame not only for directly fixing a limit of the secondary stroke movement of each mass member, but also for indirectly fixing a limit of the primary stroke movement of the corresponding key. Further, a plurality of guiding members are arranged in the frame remotely from the support members and correspondingly to the respective keys.

Abstract: A keyboard device of an electronic musical instrument has a keyboard frame, a plurality of keys which are aligned on the keyboard frame and which are vertically pivotable, a plurality of return springs each of which corresponds to one of the keys and has one end stopped by the key and the other end stopped by the keyboard frame so as to bias the key toward a nonstruck position, and a plurality of pivot members each of which is disposed on the keyboard frame at an end of a longitudinal axis of the key to correspond to one of the keys. The pivot member has a circular surface to be brought into slidable contact with a back end portion of the key so as to allow the key to perform pivotal movement. The back end portion of the key has a circular surface paired with the circular surface of the pivot member and is spring-biased against the circular surface of the pivot member by means of the return spring.

Abstract: The musical tone generating apparatus converts a movement of a man into a musical tone. Such movement of the man includes a walking or running movement, a jumping movement, a rubbing movement and a beating movement, a turning movement and the like. More specifically, a tone pitch, a tone color, a tone volume or other parameters of the musical tone to be generated is controlled based on a value of a moving speed, a value of a jumping height or a value of frictional heat produced by the rubbing movement of player's hands.

Abstract: A musical tone control apparatus comprises a main unit and at least one detector for detecting movement of player's finger, hand and the like. The main unit can be mounted on a player's wrist by use of a belt. When plural detectors are provided for detecting movements of player's fingers, tone color, tone pitch of musical tone or key-on timing is controlled based on combination of bent fingers. In order to detect bending of each finger, a joint switch is provided for each finger. In order to prevent deviation of key-on signals, a comparator is further used for comparing the predetermined threshold value with detection value corresponding to the bending of each finger so that the key-on signal is generated when the detection value exceeds the threshold value.

Abstract: 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.

Abstract: A keyboard device of an electronic musical instrument has a keyboard frame, a plurality of keys which are aligned on the keyboard frame and which are vertically pivotable, a plurality of return springs each of which corresponds to one of the keys and has one end stopped by the key and the other end stopped by the keyboard frame so as to bias the key toward a nonstruck position, and a plurality of pivot members each of which is disposed on the keyboard frame at an end of a longitudinal axis of the key to correspond to one of the keys. The pivot member has a circular surface to be brought into slidable contact with a back end portion of the key so as to allow the key to perform pivotal movement. The back end portion of the key has a circular surface paired with the circular surface of the pivot member and is spring-biased against the circular surface of the pivot member by means of the return spring.

Abstract: A keyboard device of an electronic musical instrument has a keyboard frame, a plurality of keys which are aligned on the keyboard frame and which are vertically pivotable, a plurality of return springs each of which corresponds to one of the keys and has one end stopped by the key and the other end stopped by the keyboard frame so as to bias the key toward a nonstruck position, and a plurality of pivot members each of which is disposed on the keyboard frame at an end of a longitudinal axis of the key to correspond to one of the keys. The pivot member has a circular surface to be brought into slidable contact with a back end portion of the key so as to allow the key to perform pivotal movement. The back end portion of the key has a circular surface paired with the circular surface of the pivot member and is spring-biased against the circular surface of the pivot member by means of the return spring.

Abstract: Each key of a keyboard of an electronic musical instrument is mounted on a frame to be tiltable in the vertical direction and biased to a normal position by a return spring. Each key is incorporated with a weight member embedded in a cushion member. Preferably the cushioned weight member is mounted on the front end of each key and the cushion member is made of rubber. The cushioned weight member provides a refined responsive key touch sensation.

Abstract: Each key of a keyboard of an electronic musical instrument is mounted on a frame to be tiltable in the vertical direction and biased to a normal position by a return spring. Each key is incorporated with a weight member embedded in a cushion member. Preferably the cushioned weight member is mounted on the front end of each key and the cushion member is made of rubber. The cushioned weight member provides a refined responsive key touch sensation.

Abstract: A keyboard of an electronic musical instrument is constituted by a plurality of keys and a keyboard frame. The keys are juxtaposed on the keyboard frame to be tiltable in the vertical direction. Between each key and the keyboard frame, there are provided a key return spring, a key return spring engaging member and an upper limit stop member for each key. The key return spring engaging member is fitted to either one of the keyboard frame and each key. One end of the key return spring engages the key return spring engaging member, while the other end engages either one of the each key and the keyboard frame. The upper limit stop member is disposed adjacently to key return spring and limits a returning tilting motion of each key caused by the key return spring. This adjacent disposition of key return spring and the upper limit stop member prevents bending of the keyboard frame and also makes it easy to adjust the touch and the alignment of the keys.

Abstract: A keyboard musical instrument includes a plurality of keys mounted on a casing in juxtaposed relation. Each of the keys has a retaining portion engageable with a key stop portion on the casing to limit the upward movement of the key. A resilient leaf is formed integral with each key and extends rearwardly therefrom. The resilient leaf nomally urges each key into its raised position. The resilient leaf has an engaging section at its rear portion. The engaging section is detachably retained in a retaining groove formed on the casing. A guide surface is formed on the casing immediately adjacent to and forwardly of the retaining groove for facilitating the insertion of the engaging section into the retaining groove.

Abstract: A keyboard apparatus for an electronic musical instrument is arranged that a return spring provided on each key for imparting the key a returning habit from a depressed state is comprised of either a leaf spring, a coil spring or a rod-like spring which is compressed lengthwise to be used in a buckling-deformed state, whereby warping of the spring is minimized, and the spring is allowed to progressively increase its curving after once developing the buckling without the need of increasing the compression load, thereby progressively reducing the reaction force of the spring. Thus, as the key is depressed deeper, there is obtained a lighter sense of key touch, and thereby a key touch resembling that of a piano is obtained.

Abstract: There is disclosed a method of producing a multi-key structure for keyboard musical instruments. A molding material is filled in a mold to form a molded structure which has a proximal end portion and a plurality of juxtaposed key portions extending from the proximal end portion. Molding is carried out in a state that the respective adjacent key portions diverge toward their free ends. The molded structure is removed from the mold, and the proximal end portion is deformed in such a manner that the plurality of key portions are brought into parallel relation to one another to provide the multi-key structure.

Abstract: A keyboard device of an electronic musical instrument has a keyboard frame, a plurality of keys which are aligned on the keyboard frame and which are vertically pivotable, a plurality of return springs each of which corresponds to one of the keys and has one end stopped by the key and the other end stopped by the keyboard frame so as to bias the key toward a nonstruck position, and a plurality of pivot members each of which is disposed on the keyboard frame at an end of a longitudinal axis of the key to correspond to one of the keys. The pivot member has .[.a circular.]. .Iadd.an arcuate .Iaddend.surface to be brought into slidable contact with a back end portion of the key so as to allow the key to perform pivotal movement. The back end portion of the key has .[.a circular.]. .Iadd.an arcuate .Iaddend.surface paired with the .[.circular.]. .Iadd.arcuate .Iaddend.surface of the pivot member and is spring-biased against the .[.circular.]. .Iadd.arcuate .Iaddend.