Abstract: To provide an electronic upright piano providing a key touch of an acoustic upright piano. An action load simulation member (2) provided in the electronic upright piano is composed of a wippen (15) rotating and rising when a depressed key (11) is rotated, a jack (17) rising together with the wippen (15) until a jack tail (17a) contacts a regulating button (16), a hammer butt (18) rotatably supported by a center pin (18b) for contacting or leaving the jack (17), a hammer shank (21) connected to the hammer butt (18) and provided with a hammer (23), and a hammer stopper (32) which can contact the tip of the hammer (23). The wippen (15), the jack (17) and the hammer butt (18) are rotated about separate axes, respectively. In the electronic upright piano, the let-off timing is the same as that in an acoustic upright piano.

Abstract: A keyboard assembly is constructed by assembling keyboard units. Herein, a hook is formed at one end of the keyboard unit, while an engaging portion (e.g., recess) is formed at another end of the keyboard unit. So, the keyboard units are assembled together in such a way that a hook of a keyboard unit engages with a recess of an adjacent keyboard unit. The keyboard unit is constructed by piling up at least a white key unit having white keys and a black key unit having black keys. Each key unit is formed by the resin to integrally contain keys, connections and a key support. The keys are connected to the key support by the connections such that each of the keys is supported to have a capability of swinging up and down in key-depression-release directions. The connection is constructed by a thick-wall portion whose width is greater than a width of a back end of the key and a thin-wall portion which works as a hinge.

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: Preferred embodiments include a jack holder 48 that is free to swing in accordance with the depression operation of a key 10, a first elastic member 52 that impels the jack holder 48 and applies the first counter force to the key 10 against the key depression action, the jack 42 that, together with being established so that it is not possible for it to swing with respect to the jack holder 48 during the depression operation of the key 10, is also established so that it is free to swing with respect to the jack holder 48 during the releasing operation of the key 10 and the second elastic member 56 that impels the jack 42 and applies the second counter force, which is smaller than the first counter force, to the key 10 against the key releasing action.

Abstract: A keyboard musical instrument has an instrument housing and a keyboard chassis integrally formed as a single piece. The keyboard musical instrument has at least one key movably supported on the keyboard chassis, a lower limit stopper for limiting the lowest descending position of the at least one key, a key switch including a movable contact and a fixed contact provided between the at least one key and the keyboard chassis, and an upper limit stopper disposed between the at least one key and the keyboard chassis for limiting an upper-most ascending position of the at least one key. The upper limit stopper is provided on a member that is independent of the keyboard chassis.

Abstract: A keyboard, having a plurality of keys arranged so as to be pivotable upward and downward and a plurality of light emitters arranged under the keys in one-to-one correspondence therewith, selectively causes the light emitters to emit light, thereby teaching keys to be depressed. A base resin, which forms each of the plurality of keys, has transparency and contains a pigment which colors the base resin and a light scattering agent having a light diffusion property. By virtue of the use of the pigment and the light scattering agent, a surface color which confers a refined feature on the keys can be realized, and accordingly a product with an excellent appearance can be attained. Moreover, by virtue of the blending of the pigment and the light scattering agent, the keys can shine uniformly without a difference in brightness when their corresponding light emitters are lighted, and a keyboard instrument player can fully recognize by his/her eyes that the keys shine.

Abstract: In a reduced-size keyboard in a keyboard instrument, at least one apex of an angle in at least one key or bracing member is disposed at a different longitudinal position than any other apex in any key or bracing member.

Abstract: A musical instrument, comprising a neck and a body. A chord selector is present on the neck, and a note selector is present on the body. The chord selector comprises a plurality of locations, each having a tonic and a quality. The note selector is a touch sensitive strip that is linearly arranged like a piano keyboard. A note is sounded only if it is simultaneously pressed on the note selector, and is present in one of the chords selected on the chord selector. Thus, once a chord is selected, it may be picked, strummed, or arpeggiated by employing different hand motions upon the note selector.

Abstract: A keyboard device for a keyboard-based musical instrument comprises a plurality of chassis arranged in a left-to-right direction, and a plurality of keys attached to the plurality of chassis for pivotal movements and arranged in the left-to-right direction. The overall chassis for the keyboard device is divided into a plurality of chassis which can be separately manufactured, so that the size of each chassis can be reduced as compared with a conventional keyboard device for which a single chassis is manufactured. Since this results in a reduction in scale of manufacturing facilities including a mold and a press machine used for manufacturing the chassis, and easier adjustments to the mold in a trial manufacturing stage, a manufacturing cost of the chassis, i.e., a manufacturing cost of the keyboard device can be reduced.

Abstract: To provide an electronic piano maintaining a compact appearance and providing the key touch equivalent to that of an acoustic piano. A hammer equivalent member is composed of a butt, a L-shaped member and a catcher shank. When the butt is pushed up by a jack responsive to the key depression, the hammer equivalent member starts rotating in a direction reverse to the rotary direction of a depressed key. Subsequently, after the jack leaves the butt, the hammer equivalent member continues to be rotated inertially. By contacting the projection of the L-shaped member of the hammer equivalent member, a stopper stops the inertial movement of the hammer equivalent member. The hammer equivalent member is almost equivalent to the hammer assembly of the usual acoustic piano in inertial moment and the angle formed by the center of gravity relative to a virtual perpendicular passing a center pin. Furthermore, the hammer equivalent member is shorter than the hammer assembly in appearance.

Abstract: A musical keyboard instrument (EM1) keyboard which has a plurality of keys, a common pivot point for said keys and a spring biases each key to a uniform position, each key having an associated weight member and a common fulcrum point for each associated weight member, and each key having a dependent weight actuator member engaging its associated weight member, respectively, such that when a key is depressed by a musician the "feel" to the musician is that of a given type of keyboard instrument. A device for disabling the effect of at least some of said associated weight members changes the "feel" to the musician of the keyboard. The device for disabling includes a bar member pivotally mounted to the instrument frame and beneath the associated weight members and a device for rotating the bar member in a direction to rotate the associated weight members about the common fulcrum point and disengage the weight actuator members from engagement with the associated weight member.

Abstract: A keyboard apparatus with at least one key having a rotation fulcrum and an exterior front end face on the opposite side of the rotation fulcrum in a performer side. The exterior front end face of the at least one key defines a front lower section. An extended section is provided at the front lower section of the at least one key that extends from the exterior front end face of the at least one key toward the performer side, and a mass member is attached to the extended section. The mass member therefore extends forwardly from the external front end face of the at least one key toward the performer side.

Abstract: A keyboard assembly includes a plurality of white keys and black keys juxtaposed to each other and each having a body disposed to be depressed, and a connecting portion, and a key support that supports the body. The connecting portion connects the body to the key support in a fashion permitting the body to swing in directions of key depression and release while limiting lateral motions of the body. The body of each of the white keys has an extension formed integrally therewith and laterally extending therefrom at a location under the body of a corresponding one of the black keys in such a manner that the extension overlaps with the bottom surface of the body of the corresponding one of the black keys.

Abstract: An electric tutor is assembled with an upright piano having a keyboard and a key stop rail laterally extending over the rear end portions of the black/white keys, and includes a comb-like flexible indicator attached to the key stop rail, wherein the comb-like flexible indicator has flexible insulating strips connected to a rigid printed board attached to the key stop rail by means of connectors and lying on the black/white keys, optical indicators attached to the flexible insulating strips and signal lines printed on the back surfaces of the flexible insulating strips for selectively supplying driving signals to the optical indicators for radiating light, thereby guiding the fingers of a player in accordance with a music score.

Abstract: Aspects of the present invention provide relatively inexpensive methods and apparatus for modifying existing pianos to provide interchangeable keyboards of different sizes without sacrificing or impairing the quality of the original piano. The keys of a standard piano are removed and the pins in the front rail of the key frame are replaced with pins which are more closely positioned. The original keys are then replaced with new keys of narrower dimensions which are more closely positioned in the area of the front rail.

Abstract: 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.

Abstract: An keyboard assembly for an electronic musical instrument is mainly constructed by a key frame, a key, a key switch and an assembly guide member. A fixing portion of the key is supported by the key frame such that a front portion of the key can be freely rotated up and down. An actuator is attached to and projected downward from a lower side of the key. The key switch (or a key-depression sensor) has an elastic projecting portion at its upper end. This key switch is provided on the key frame and is driven by the actuator, which depresses down the elastic projecting portion of the key switch when the key is depressed down. The assembly guide member guides the key when the key is moved in an assembling direction (i.e., a longitudinal direction of the key) in order to carry out an assembling operation to assemble the key and the key frame together.

Abstract: A silent electronic keyboard instrument for operation in conjunction with a synthesizer for transmitting sound only electronically to a headphone terminal, and exhibiting keyboard operation substantially duplicative of acoustic piano keyboard operation.

Abstract: A musical notation system which displays the seven notes of any chosen scale on a staff of eight lines and seven spaces, which are typically arranged in a vertical fashion, and which is a graphical representation of a keyboard. No sharps or flats are used to designate a key, but rather only the valid notes of any particular diatonic scale are provided with positions on the staff. Notations which indicate octaves, beats per measure, the selected Key and the mode are all provided. Symbols for timbre, loudness, duration of notes and rests are the same as conventional music notations.

Abstract: An keyboard assembly for an electronic musical instrument is mainly constructed by a key frame, a key, a key switch and an assembly guide member. A fixing portion of the key is supported by the key frame such that a front portion of the key can be freely rotated up and down. An actuator is attached to and projected downward from a lower side of the key. The key switch (or a key-depression sensor) has an elastic projecting portion at its upper end. This key switch is provided on the key frame and is driven by the actuator, which depresses down the elastic projecting portion of the key switch when the key is depressed down. The assembly guide member guides the key when the key is moved in an assembling direction (i.e., a longitudinal direction of the key) in order to carry out an assembling operation to assemble the key and the key frame together.

Abstract: A plate-like member or rib 19 is extended in a back-to-front direction of a key 14. The height of a rear end of a flat portion 12 is regulated by an upper flange portion 21c and a lower flange portion 22 of the rib 19. A wippen 30 provided with a jack 44 is attached via a bearing member 33 for supporting a wippen swing axis 31 onto a chassis 11. A hammer 50 is attached via a center rail 60 provided with a bearing member 65 for supporting a hammer swing axis 51 onto the chassis 11. A bearing 16 for supporting a key support 15 is fixed to the chassis 11 with a flange portion 61 of the center rail 60 abutting on a rear L-shaped leg 18. A substantially L-shaped rail 67 is fixed with a screw on the center rail 60, which has on its top face a hammer cushion 68 for abutting a rest portion 52 of the hammer 50 and on its lower face a regulating felt for abutting on a hack tail 47.

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 assembly comprises at least one key unit including a plurality of keys each having a front end and a base end, a common key support supporting the keys, and a connecting portion provided on the base end of each of the keys and connecting between each of the keys and the common key support. The keys are formed integrally with the connecting portion and the common key support in a manner such that the keys are each connected via the connecting portion to the common key support for swinging about the common key support in a direction of depression and release of the keys and in a direction in which the keys are juxtaposed. The keys define gaps therebetween, each of which becomes progressively larger toward the front end of an associated one of the keys.

Abstract: A musical instrument includes a two-dimension array of note producing elements wherein the elements along one dimension of the array have three-quarter steps or increasing fundamental frequencies F.sub.n according to the equationF.sub.n =F.sub.0 *2.sup.n/8wherein F.sub.0 is the fundamental frequency of the first note producing element in the one dimension and n is the number of the note producing element in the one direction from the first note producing element. The note producing elements along a second dimension of the array have fundamental frequencies which differ by frequency differences (such as perfect fourth intervals) greater than the frequency differences between adjacent note producing elements along the one dimension of the array.

Abstract: An object is to provide an antibacterial keyboard which keeps to be clean and can be prevented from being discolored by growing or grown bacteria. Methyl methacrylate resin as acrylic resin, and a ceramic body as an antibacterial agent prepared by mixing and sintering calcium phosphate and silver metal are used: 0.5% to 2% by weight of the ceramic body prepared by mixing and sintering calcium phosphate and silver metal is blended and uniformly dispersed in the methyl methacrylate resin. The blend is injection molded, to form piano natural key coverings. The piano natural keys covered with such coverings are superior in an antibacterial, keep to be clean and can be prevented from being discolored by growing or grown bacteria.

Abstract: 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.

Abstract: Disclosed is an electronic musical instrument comprised of operators organized in repeating patterns of seven. The operators are electronically interpreted to correspond only to the valid notes of a selected scale. The repeating patterns of seven notes directly corresponds to the vast majority of mucis theory and thus constitutes an enormous simplification in the art of learning, performing and composing music. The present invention enables users of the electronic musical instrument to master chord and note progressions in any scale and mode by learning only a single set of note patterns, in contrast to the myriad scales, chord and note patterns which must be learned on traditional keyboard and pedal devices.

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 music instrument includes a keyboard, key action mechanisms functionally connected to keys of the keyboard, strings assigned notes of a scale and hammer assemblies for striking the strings. The hammer assemblies have respective hammer heads formed of metallic powder containing synthetic resin so as to exactly regulate the weight to target values.

Abstract: In a method of and means for producing musical note relationships there is provided an array of staggered lines or rows or columns of symbols, in which each symbol represents a musical note. Each line may comprise a repeated series of twelve symbols forming a musical series of semitones known as a chromatic scale, and each line is staggered with respect to adjacent lines such that groups of the symbols which represent the same musical note relationship, such as intervals, scales, chords, etc., form the same visual configuration, for example diagonal configurations or vertical configurations at respective locations in the array. The array may comprise a keyboard including a plurality of keys each representative of a particular musical note.

Abstract: Improvements to keyboards for electronic pianos and the like, wherein a support, preferably made of sheet metal, with a U-shaped section and a flat section and provided with a number of hammers equal to the number of keys, which hammers are made integral with the support by means of specific pivoting elements. These hammers are preferably made of metal and suitably shaped and balanced for actuation by the keys. An elastic escapement member is carried by the portion of the hammer making contact with the key typically by coated with a rubber element provided little step which, when the key is depressed and the thrust element inside the key comes into contact with the step, produces a slight release, similar to the feeling of escapement one perceives when playing a conventional piano.

Abstract: A stringed musical instrument such as an electric or acoustic guitar and a bass guitar in combination with a piano-type keyboard. The musical instrument of the present invention includes a body with a neck extending from the body and a plurality of strings extending across the neck and the body. The body has a portion extending outward from the strings upon which the keyboard is adjustably attached using a bracket The present invention provides a user with ready access to both the stringed instrument and the keyboard. The user may utilize the stringed instrument and keyboard separately alternating therebetween or simultaneously having one hand of the user play the keyboard as well striking and/or strumming the strings. The user also has the ability to adjust the positioning of the keyboard in relation to the stringed instrument.

Abstract: A musically enhanced computer keyboard (12) (FIG. 3) having a portion 106 (FIG. 5 ) resembling a partial piano style keyboard having a standard "QWERTY" alpha-numeric key arrangement (102) and a modified function key row arrangement (108). Musical information is entered by using the modified function key row (108) (keys (110) through (128)) as the piano style keyboard's black keys and using the symbol and number keys (130) through (158) as the piano style keyboard's white keys. Textual information is entered by depressing an "Alt" key (168) while concurrently depressing a musical note key (keys (110) through (128)) which causes a textual character associated with the particular key being depressed to appear on a display monitor.

Abstract: An apparatus, with an oil damper for damping the closing of a fall board on a main body of a musical keyboard and permits opening of such keyboard without damping when the fall board is opened. The oil damper has a body with a cylindrical chamber, having a stop projecting radially inward, such body being fixed to said fall board. A pivotal member in the chamber having a shaft and a projecting portion on said shaft in said chamber, such shaft extending outwardly from such chamber and through a liquid tight seal at one end of the chamber, the outwardly extending shaft being fixed to the main body. A movable arcuate valve in the cylindrical chamber and slidable on an inner wall of the chamber, such valve having radial portions extending inward toward such shaft and at opposite sides of the projecting portion of the pivotal member.

Abstract: A keyboard musical instrument selectively enters into an acoustic sound mode for generating acoustic piano tones and an electronic sound mode for generating electronic sounds instead of the acoustic piano tones, and a stopper is changed between a free position and a blocking position by an actuator controlled through detection with photo-interrupters, thereby eliminating aged deterioration from the position control between the free position and the blocking position.

Abstract: A stringed musical instrument is disclosed as including a body with an extending portion on to which a piano-type keyboard is attached. The combination provides the user with the ready access to both the stringed instrument and the keyboard. The user may utilize the stringed instrument and keyboard separately alternating therebetween or simultaneously having one hand of the user play the keyboard as well striking and/or strumming the strings.

Abstract: A keyboard musical instrument has a hammer stopper provided between strings and hammer assemblies and operative to prevent the strings from hammer heads for electronically producing sounds in response to a fingering on a keyboard, and a driving mechanism for the hammer stopper is provided on the opposite side of the hammer assemblies so as to accommodate the driving mechanism in a wide space.

Abstract: A keyboard assembly is to be connected to a keyboard port of a host computer and includes a keyboard housing having opposite first and second horizontal faces and opposite vertical side walls at opposite longitudinal ends of the horizontal faces. An array of organ keys is disposed resiliently on the first horizontal face. An organ circuit array is disposed in the keyboard housing and is associated operably with the organ keys. An array of computer keys is disposed resiliently on the second horizontal face. A computer circuit array is disposed in the keyboard housing and is associated operably with the computer keys. A pair of upright support panels is mounted respectively on the side walls of the keyboard housing. Each of the support panels has two opposed distal ends which project respectively past the organ keys and the computer keys. A processor unit is connected electrically to the organ circuit array and the computer circuit array and is to be connected to the keyboard port of the host computer.

Abstract: A keyboard includes a key which drives a swing arm. The swing arm transfers return force from a coil spring or other return force mechanism to the key. The rotational axis of the swing arm is perpendicular to the length of the keyboard. Various key position sensing means utilizing the swing arm are disclosed as well.

Abstract: An apparatus for slidingly opening and closing a keyboard lid for covering a keyboard of a keyed instrument between an open position and a close is provided. The keyboard lid has a front end with a pair of opposite sides and a rear end with a pair of opposite sides. A pair of front guide projections project laterally from the opposite sides of the front end of the keyboard lid. A pair of rear guide projections project laterally from the opposite sides of the rear end of the keyboard lid. A pair of side plates are arranged on opposite sides of the keyboard. Each one of the pair of side plates has a front guide groove engaging with a respective one of the pair of front guide projections and a rear guide groove engaging with a respective one of the pair of rear guide projections. In this manner, the keyboard lid is slidably guided between an open position and a close position.

Abstract: In order to allow a player to perform a music without an acoustic sound, a stopper blocks hammer shanks before impacts of hammer heads to strings, and recesses substantially conformal to the hammer shanks are formed in cushion members of the stopper for improving durability of the cushion members.

Abstract: A stand structure for a keyed instrument having a main body with a keyboard at the front thereof, the stand structure including a first side plate and a second side plate, the first side plate and the second side plate being adapted for supporting at least a lower portion of the main body arranged between the first side plate and the second side plate; a back plate arranged between the first side and the second side plate for reinforcing the first side and the second side plate, the back plate being adapted to be arranged below the main body; a first single securing member adapted for interconnecting the main body, the back plate and the first side plate; a second single securing member adapted for interconnecting the main body, the back plate and the second side plate; and a pair of screw means, each of the pair of screw means being adapted for extending laterally through one of the first side plate and the second side plate and into the lower portion of the main body so as to secure the main body to the one

Abstract: An electronic music keyboard that folds in the middle bottom-to-bottom, and pivots in the middle, back-to-back. When fully open along both planes, the keyboard looks and performs in a conventional manner. When partially pivoted, the keyboard may be supported by an ergonomic belt, or standard means and played hanging from the body of the operator forming an adjustable, inverted "V" shape on a vertical axis. When fully pivoted, the keyboard may be worn over the chest of the operator and played much like a double-keyboard accordian. The ends form a carrying handle and the keyboard folds neatly into a carry bag. This device may also be fabricated from appropriate materials to act as a support for prior art small MIDI keyboards.

Abstract: An acoustic piano, an electronic sound producing system and a controlling system form a keyboard instrument for selectively producing acoustic sounds and electronically synthesized sounds, and the controlling system has a catcher stopper for restricting rotations of catchers before hammer heads strike sets of strings in the electronic sound producing mode, thereby giving the unique piano key-touch to a player without mixing noise with the synthesized sounds.

Abstract: A keyboard cover apparatus for an electronic keyboard instrument has a keyboard main body having a supporting member on each side thereof. A keyboard cover member has an arm on each side thereof and the arm is rotatably supported by the supporting member. An interlocking device is provided to hold the keyboard cover member in a first closing position in which a predetermined clearance is maintained between the keyboard cover member and the keyboard main body and in a second position in which the clearance is substantially eliminated.

Abstract: A keyboard instrument for the natural tone system with at least one keyboard whose keys are assigned to the overtones in a predetermined sequence. According to the invention, the keyboard is optimally adapted to the conditions of the natural tone system by the fact that 16 keys are provided per octave which are arranged and constructed in such a way that the natural tones can be played in sequence on three playing levels. One peculiarity of the invention consists of the boxed arrangement of the keys on the three playing levels, whereby only the "harmonic keys" are arranged on the frontal playing level, the "melodic keys" and the tapered "harmonic keys" are arranged on the central playing level, and that the tapered section of the "melodic keys," a further tapered section of the "harmonic keys" and the "chromatic keys" are arranged on the rear playing level. The adjacent key sections on each playing level are equally wide.

Abstract: A keyboard lid comprising a lid body and a frame plate attached to the edge of the lid body for reinforcing it in which said frame plate has a decoration plate arranged at the outside of said lid body and a reinforcing plate arranged at the inside of said lid body and that said decoration plate and said reinforcing plate are formed separately with each other.

Abstract: An acoustic piano is equipped with an electronic sound generating system, and a key bed structure is angularly movable between an acoustic sound mode and an electronic sound mode for changing gaps between hammer heads and sets of strings, thereby allowing a player to perform a music with acoustic sounds or synthesized sounds.