Abstract: The present invention provides a rear projection simulator system with a free-form fold mirror. The system includes a high definition projector and a curved screen. The free-form fold mirror is interposed between the projector and the screen. The free-form fold mirror includes one or more non-planar (e.g., curved) portions to eliminate or reduce loss of resolution of the projected image near the edges or boundaries of the image.

Abstract: A keyboard device is provided whose entire device body can be compactified even if a hammer member length in its front and rear direction is increased and a keyboard instrument including the keyboard device. The keyboard device includes a plurality of keys, a transmission member which is rotated in response to a key depression operation performed on a key among the plurality of keys, and a hammer member which is rotated in response to rotation of the transmission member and applies an action load to the key, in which the hammer member includes a hammer arm and a hammer head provided on a front side of the hammer arm, and the hammer arm is rotated around a hammer rotation center located on a rear side of the hammer arm in response to the key depression operation performed on the key.

Abstract: A keyboard with adjustable touch for a musical instrument, each key being a lever divided into front and rear arms, front arm forms on its upper part an operation surface and its lower part interacts with a centering guide, and the rear arm comprises, on its upper part, a counterweight and its lower part interacts with a stop each key comprises a key magnet (KM) mounted on the rear side, facing another magnet (SM) that is mounted on a regulation device which is affixed to the musical instrument chassis, the magnets (KM and SM) are substantially placed face to face, opposed by their equivalent polar faces, the relative position they have to each other is set by the regulation device and generating the effect on the keyboard touch.

Abstract: An electric stringed musical instrument includes: a string which vibrates by a performance operation; a body which supports the string via a bridge; a pickup sensor mounted on a portion which vibrates by a vibration of the string, the pickup sensor being configured to detect a vibration having propagated from the string and output an electric signal; a supporter having a spring structure which supports the bridge with respect to the body; and a damper mounted on a portion which vibrates by a vibration of the string, the damper being configured to damp a vibration of the bridge.

Abstract: An accessory device removably mounted to the headstock of a string instrument including an arm assembly for, actuating the keys of a keyboard instrument. The distal end of the arm assembly includes at least one tip cooperatively shaped to actuate the keys of a keyboard instrument. The arm assembly having an elongated arm member that is slidably and lockingly mounted to a clamp assembly that is removably mounted to the stock.

Abstract: A hammer device for a keyboard instrument, enabling improvement of efficiency and yield, in manufacturing weights to be attached to each hammer body while suppressing an increase in manufacturing cost. Each hammer includes a hammer body having a weight mounting portion, a common weight attached to one of left and right side surfaces of the weight mounting portion, and an adjustment weight having a length set according to a touch weight required by the associated key and attached to the other of the left and right side surfaces of the weight mounting portion. A chassis has a plurality of partition parts, and on the left and right surfaces of the hammer body, there are formed left and right opposed protrusions, respectively, each of which protrudes outward of the weight and is opposed to a partition part associated therewith via a predetermined clearance.

Abstract: A keyboard apparatus capable of enhancing the return capability of hammer assemblies upon key release to improve the capability of repeated key striking and capable of reducing a height size of action units to make the keyboard apparatus compact. The keyboard apparatus includes hammer assemblies each having a butt disposed pivotable about a hammer pivot shaft and a hammer shank extending from the butt. In a non-key-depression state, the hammer shank obliquely extends downward. As viewed from side, a straight line passing though a gravity center position of the hammer assembly and the hammer pivot shaft forms an acute angle less than 45 degrees relative to a horizontal plane in the entirety of a key depression and key release stroke.

Abstract: An upright piano main action rail with a special cross sectional shape of its lower half that angles or curves towards the back of the piano to effectively relocate the lower front surface of upright piano main action rail from a position in front of the row of whippen flanges as with the prior art to a relocated new position behind the row of whippen flanges to enable the front mounting of whippen flanges to the main action rail. Upright piano main action rail has all whippen mounting holes located its the lower front surface instead of the lower rear surface as with prior art upright piano main action rails.

Abstract: A keyboard apparatus capable of being easily designed to have action units whose upper end positions are made low and whose efficiency of drive of whippens is increased. Each of keys of the keyboard apparatus has an upper front part, a bent part extending downward from a rear end of the upper front part, and a lower rear part extending rearward from a lower end of the bent part. An upper surface of a rear end portion of the lower rear part nearly horizontally extends at a height position lower than that of a key fulcrum. Action units are disposed above respective ones of rear end portions of the keys. A driven point of a whippen of each action unit is located at a position lower than the key fulcrum in a non-key-depression state.

Abstract: The invention relates to a piano hammer for striking the strings of a piano, including a hammer shank and a hammer head, which is covered with a cover along at least part of its peripheral surface. The aim of the invention is to provide an improved piano hammer which can be tuned in a simple and reproducible, especially also reversible, manner. According to the invention, the cover has a varying thickness along the peripheral surface and the hammer head can be adjusted with respect to the position of its peripheral surface with which it impacts the one or more string(s) to be struck.

Abstract: A piano action flange with an open-slotted rail attachment feature that is a slot-shaped void completely through the piano action flange, running in the longitudinal direction of the piano action flange, with width slightly larger than the outer diameter of the thread end the flange screw but smaller that the head diameter of the flange screw, where the slot-shaped void is open on one end, breaking through the end of said piano action flange, to leave the slot-shaped void open and accessible from the end of the piano action flange.

Abstract: A keyboard device capable of reconstructing a unique clicking sense of an acoustic piano is provided. A first incline portion (a plane or curved surface) of a sliding surface is inclined towards a direction gradually departing from a base portion of a protrusion along a displacement direction of the protrusion in a key-pressing operation for reducing a resistance exerted on the protrusion and suppressing a gradual increase of a sense of resistance. Moreover, a bump portion located at where the protrusion reaches after sliding through the first incline portion is used to increase the resistance exerted on the protrusion for increasing the sense of resistance. When the protrusion crosses over the bump portion, the sense of resistance is reduced. Accordingly, variation in the sense of resistance before and after the bump portion is increased, and the unique clicking sense of the acoustic piano is reproduced.

Abstract: A hammer assembly for a grand piano comprising: a hammer, a hammer shank, a tubular lever interface, and a moveable knuckle. A grand piano tubular lever interface comprises: a deep socket; a set of two hinge pin attachment holes; a void area; and a moveable knuckle visual location system. A moveable knuckle comprises: a spline; a resilient core; a synthetic buckskin wear surface, and a moveable knuckle visual location system. Novel hammer assembly allows for a direct lever relationship between hammer shank and knuckle without requirement of a forked end hammer shank with knuckle slot. Best mode spline comprises: an upright rectangular portion and a wide base portion, wherein wide base portion includes an intricate shape. Intricate shape comprises: at least one recess area and at least one protrusion area. The inverse of intricate shape is included on the bottom of the tubular lever interface.

Abstract: The invention relates to a piano hammer for striking the strings of a piano, comprising a hammer shank and a hammer head, which is covered with a cover along at least part of its peripheral surface. The aim of the invention is to provide an improved piano hammer which can be tuned in a simple and reproducible, especially also reversible, manner. According to the invention, the cover has a varying thickness along the peripheral surface and the hammer head can be adjusted with respect to the position of its peripheral surface with which it impacts the one or more string(s) to be struck.

Abstract: A keyboard apparatus capable of enhancing the return capability of hammer assemblies upon key release to improve the capability of repeated key striking and capable of reducing a height size of action units to make the keyboard apparatus compact. The keyboard apparatus includes hammer assemblies each having a butt disposed pivotable about a hammer pivot shaft and a hammer shank extending from the butt. In a non-key-depression state, the hammer shank obliquely extends downward. As viewed from side, a straight line passing though a gravity center position of the hammer assembly and the hammer pivot shaft forms an acute angle less than 45 degrees relative to a horizontal plane in the entirety of a key depression and key release stroke.

Abstract: A keyboard apparatus capable of being easily designed to have action units whose upper end positions are made low and whose efficiency of drive of whippens is increased. Each of keys of the keyboard apparatus has an upper front part, a bent part extending downward from a rear end of the upper front part, and a lower rear part extending rearward from a lower end of the bent part. An upper surface of a rear end portion of the lower rear part nearly horizontally extends at a height position lower than that of a key fulcrum. Action units are disposed above respective ones of rear end portions of the keys. A driven point of a whippen of each action unit is located at a position lower than the key fulcrum in a non-key-depression state.

Abstract: A keyboard apparatus configured that heavy loads to support keys and hammers are perpendicularly applied to front-side and rear-side contact portions and the area of a front part of a frame as seen from side can be reduced, thereby suppressing an amount of use of resin. The keyboard apparatus includes a frame integrally formed by resin and mounted with a stopper mounting portion to which an initial stopper is mounted. The frame is supported on a keybed only by front-side and rear-side supporting portions respectively contacting the keybed at locations beneath hammer pivot shafts and beneath key supports. In a longitudinal region between the stopper mounting portion and the front-side supporting portion, the height position of a lowermost part of the frame become higher at a position closer to the stopper mounting portion.

Abstract: This invention relates to a string-striking device for a piano which enables the adjustment of strength degrees more than at lest three, the moving interval between a hammer that is molding magnet and an excentricity rod is fixed piano body so that a player can choose freely from strength degree more then 3 comprising excentricity rod which is point a of the FIG. 7 point b of the FIG. 9 and a point from a to b of the FIG. 11.

Abstract: A musical instrument apparatus including multiple parallel strings defining a string line and a keyboard overlay positioned at an acute angle to the string line to allow for consistent playing feel by consistently positioning the hammers on the keys while allowing large key spacing with minimized distance between the strings. The hammers are directly mounted to the keys and are adapted to either cause vibration of the strings or clamp the strings against the upper surface of a neck board so that the strings may have multi tonal capabilities as is commonly used with a fret board neck on a guitar. The strings can be played with just the keyboard, but the strings also extend past an edge of the keyboard overlay so that the user can directly play the multiple parallel strings to achieve a guitar sound. Both an electrical pickup and an acoustical body are provided for further sound variety.

Abstract: 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.

Abstract: A universal grand piano piano action that has adjustable connections between the repetition base, heel, and rest cushion bracket of the piano action to provide a piano action that can be adjusted to fit any grand piano. Other components of the grand piano piano action, such as the jack and flanges, may require specific design and manufacture for each brand of grand piano. Universal grand piano piano action also allows true simultaneous half stroke keyboard design for both the white and sharp keys of a piano and includes the methods for installing simultaneous half stroke keyboard design into a grand piano.

Abstract: An electronic keyboard instrument with a hammer action, in which a circuit board for generating electronic musical tones can be disposed at a location for easy maintenance and for effective space utilization. Front and rear bars are bridged between side plates of an instrument main body so as to extend parallel to each other in the left-right direction and reinforce the instrument main body. A hammer action mechanism having hammers for respective keys is disposed rearward of a key-depression part of a keyboard and upward of a rear end portion of the keyboard, and a board tray is bridged between the front and rear bars. The board tray and the circuit board are located upward of the hammer action mechanism.

Abstract: A stopper for a keyboard-based musical instrument is provided for accomplishing a good stopping feeling of a pivotable member, thereby making it possible to improve a touch feeling and restrain collision noise and other noise. A stopper 7 for a keyboard-based musical instrument with which a pivotable member 6 comes into contact while said pivotal member pivotally moves in association with a key touch, thereby restraining the pivotal movement of said pivotable member 6, comprises a mass 26, a first cushion 25 laminated on a front side of said mass 26, and a second cushion 27 laminated on a back side of said mass 26. Preferably, the mass 26 is made of a metal, and the first cushion 25 is harder than the second cushion 27.

Abstract: A moveable key lever pivot bearing system for keyboard instruments in which the pivot bearing is provided with a longitudinal slot to enable mounting the bearing over a pivot pin disposed on a balance rail mounted within the case of the instrument. The key lever, pivot pin, and balance rail all remain in fixed relationship to one another resulting in a fulcrum point change when the bearing is longitudinally shifted back and forth with respect to the pianist.

Abstract: Composite or plastic molded articles used in a grand piano piano action. The articles make up a piano action with less dynamic mass which is, thus, more responsive to the piano player. In addition, the new action provides the extremely valuable collateral benefits of increased efficiency of manufacture and maintenance. Low inertia grand piano piano action comprises a repetition base with one or more of the following: an angled main beam, an angled balancier support beam, an integrated jack button stop, and a means to optionally connect a rest cushion assembly. Low inertia grand piano piano action may also comprise a heel with extremely low mass.

Abstract: There is provided a repetition lever for a grand piano, which is excellent in shape retainability and dimensional stability and is light in weight and high in rigidity, thereby enabling required operations to be stably performed and improving the capability of repeated key striking. A repetition lever 4 for a grand piano, which performs the operation of pushing up a hammer 30 after the hammer has struck a string, is formed by a molded article of a thermoplastic resin containing long fibers for reinforcement, the molded article being molded by a long fiber process. The repetition lever 4 has reduced cross-sectional area portions 49, 50, and 54 for reducing weight thereof. The long fibers for reinforcement are carbon fibers, and the thermoplastic resin is an ABS resin.

Abstract: A hammer assembly for a grand piano comprising: a hammer, a hammer shank, a tubular lever interface, and a moveable knuckle. A grand piano tubular lever interface comprises: a deep socket; a set of two hinge pin attachment holes; a void area; and a moveable knuckle visual location system. A moveable knuckle comprises: a spline; a resilient core; a synthetic buckskin wear surface, and a moveable knuckle visual location system. Novel hammer assembly allows for a direct lever relationship between hammer shank and knuckle without requirement of a forked end hammer shank with knuckle slot. Best mode spline comprises: an upright rectangular portion and a wide base portion, wherein wide base portion includes an intricate shape. Intricate shape comprises: at least one recess area and at least one protrusion area. The inverse of intricate shape is included on the bottom of the tubular lever interface.

Abstract: A hammer with simplified structure and reduced costs that maintains its capability as a mass body to impart a touch weight. The hammer is configured such that it is possible to fix the two mass plates to the metal base plate by means of a single rivet. Therefore, the number of places in which the rivet holes are drilled and disposed in both mass plates and the metal base plate are kept to a minimum, and it is possible to limit the lightening of the weight of both mass plates and the metal base plate by that amount. As a result, since it is possible to configure the base plates and the metal base plate with smaller dimensions while maintaining the required weight, the capability as a mass body to impart a touch weight can be maintained while preventing the enlarging of the hammer overall.

Abstract: A hammer shank and shank butt for a grand piano with greatly improved rigidity and the collateral benefits of increased efficiency of manufacture and maintenance. Hammer shank comprises a long cylindrical member that is connected at one end to a traditional grand piano hammer and at the other end to a novel shank butt. Shank butt comprises: a hammer shank hole, a knuckle slot, a set of two flange attachment holes, and a void area. A traditional grand piano knuckle is attached to the knuckle slot. The shank butt is connected to the repetition flange of the piano. Thus, hammer shank is not directly connected to these members and thus can remain an integral cylindrical member without holes, notches, or voids, thereby allowing for a lighter, more rigid sub-member yielding hammer assembly with less mass. The invention provides the capability for a piano to be played with less touch weight on the keys and therefore provides a more responsive piano keyboard.

Abstract: A keyboard-type percussion instrument having sounding members arranged to correspond to respective ones of keys and capable of improving musical performance in soft tone. When a soft pedal is stepped on, a pedal connecting rod is moved upward to move an arm portion of a lifting arm upward, whereby the lifting arm is pivoted to cause capstan screws to be inserted into through holes of a key frame, thus moving a lifting bar upward so that an upper surface of the lifting bar projects from the key frame to push rear end portions of all the keys upward. As a result, standby positions of hammer felts are moved toward the sounding members, whereby the volume of a tone generated by a sounding member struck by a hammer felt corresponding to a depressed key is decreased.

Abstract: A keyboard device for a keyboard instrument, which can be manufactured by a simplified manufacturing process and at reduced manufacturing costs, is disclosed. A keyframe is formed by a molded piece of a synthetic resin. A plurality of front rail pins and a plurality of balance rail pins are arranged in a juxtaposed manner in a left-right direction at a front part and a central part of the keyframe in a front-rear direction. A plurality of keys are made of wood and each have a balance rail pin hole formed in a central portion thereof in the front-rear direction. The keys are swingably supported on the keyframe in a state where the balance rail pins are each engaged with the balance rail pin hole associated therewith and at the same time the keys are prevented from being swung in the left-right direction by the front rail pins associated therewith.

Abstract: A keyboard-type percussion instrument having sounding members arranged to correspond to respective ones of keys and capable of improving musical performance in soft tone. When a soft pedal is stepped on, a pedal connecting rod is moved upward to move an arm portion of a lifting arm upward, whereby the lifting arm is pivoted to cause capstan screws to be inserted into through holes of a key frame, thus moving a lifting bar upward so that an upper surface of the lifting bar projects from the key frame to push rear end portions of all the keys upward. As a result, standby positions of hammer felts are moved toward the sounding members, whereby the volume of a tone generated by a sounding member struck by a hammer felt corresponding to a depressed key is decreased.

Abstract: A string-striking device for a piano, where a static loading acting on a fore-end on the playing side of a key can be easily adjusted. A long weight lever (21) is provided on each key (3). The lever (21) is installed along the length direction of the key 3, on an upper part on the side opposite the playing side of the key (3). The installation is made such that one end of the lever (21) is vertically pivotably fixed to a piano body and the vertically displaceable free-end side of the lever is in contact with the upper face of the key (3) by its own weight to apply a load on the key (3). The structure above enables a static load on the key (3) to be adjusted by replacing the lever (21) without disassembling the string-striking device and removing the key (3).

Abstract: A piano hammer comprises an elongate hammer head having a nose portion defining side surfaces and a felt covering extending about the nose portion with tail portions of the felt covering affixed to the side surfaces. The felt covering defines a substantially elliptical peripheral surface from a top region for striking a piano string to front and back regions. An elongate strip is arranged on the peripheral surface of the felt covering in the top region, extending along the front and back regions to points beyond the hammer equator. This strip or “voicing tape” is made of a synthetic non-woven fabric material, preferably of the type sold under the registered trademark Pellon.

Abstract: A piano key mechanism for a pianoforte with improved dynamic performance has weights placed within each keystick in the region between the pivot point of each key and a point midway between the pivot point and the ivory end of the keystick. The arrangement of weights reduces the overall inertia of the keysticks thus improving the dynamic performance of the musical instrument and results in an average of the downweight and upweight which is heavier than the conventionally accepted value for that key on a keyboard.

Abstract: A back check for a piano is provided for locking a returning hammer in a pivotal movement without fail and for saving the manufacturing cost. The back check is used for locking the hammer in a pivotal movement for returning after it has struck a string to prevent the hammer from rebounding. A back check, disposed at a location at which the hammer is locked, extends in a vertical direction, and has an adhering surface which rises in a central portion thereof in the vertical direction. An under felt is adhered on the adhering surface of the back check body. A sheet-like cushion material, which is adhered to the back check body to cover the under felt, is formed with a locking surface in a predetermined curved shape conformal to the adhering surface for locking the hammer.

Abstract: A string-striking device of a piano by which static loading applied to a front end of a key on the playing side can be readily adjusted. Each key (3) is provided with a long weight lever (21) disposed along the length direction of the key 3 at an upper part of the key (3) on the side opposite of the key to the playing side. The weight lever (21) is arranged such that one end thereof is fixed to a piano body so as to allow the weight lever (21) to freely swing up and down, and the other open end, which can be vertically displaced, is brought into contact with the upper surface of the key (3) and applies its own weight on the key (3). Thus, the static loading applied to the key (3) can be adjusted by replacing the weight lever (21) without disassembling the string-striking device and removing the key (3).

Abstract: There is provided an action part for a piano, which has higher rigidity than that of an action part made only of a synthetic resin, while maintaining advantageous effects as provided by the use of the synthetic resin, thereby making it possible to obtain the sound volume with a smaller key depression energy, and enhance responsiveness of the action. The action part is pivotally moved along with depression of key to thereby transmit key depression energy generated by depression of the key, to a hammer. The action part is formed by a molded article of a thermoplastic resin that is molded by a long fiber process and contains long fibers for reinforcement.

Abstract: A hammer with simplified structure and reduced costs that maintains its capability as a mass body to impart a touch weight. The hammer is configured such that it is possible to fix the two mass plates to the metal base plate by means of a single rivet. Therefore, the number of places in which the rivet holes are drilled and disposed in both mass plates and the metal base plate are kept to a minimum, and it is possible to limit the lightening of the weight of both mass plates and the metal base plate by that amount. As a result, since it is possible to configure the base plates and the metal base plate with smaller dimensions while maintaining the required weight, the capability as a mass body to impart a touch weight can be maintained while preventing the enlarging of the hammer overall.

Abstract: A jack used in an action mechanism of a piano has substantially an L-shape, composed of a big jack portion and a small jack portion. The thickness of the small jack portion is made smaller than that of the big jack portion in a direction of key arrangement in a state of the jack being fitted in the piano. By reducing the weight of the small jack portion as above, the time required for the jack to return to a position capable of pushing up a part of a striking member can be shortened. Accordingly, more frequent repetitive striking is allowed within a predetermined period.

Abstract: An action in an acoustic piano is provided which can reproduce the touch and feel of the key depression generated in a normal performance mode even in a silent performance mode. The acoustic piano is capable of being switched between the normal performance mode and the silent performance mode. In the silent performance mode, a rotation lever of a transmission switching mechanism disconnects the hammer operating portion from the key. A load switching mechanism is rotated to lower the tip of a weight lever to abut directly upon the upper face of the key. Then, the weight lever swings up and down corresponding to the key depression of a player, closely reproducing the touch and feel of a conventional acoustic piano.

Abstract: There is provided an action part for a piano, which has higher rigidity than that of an action part made only of a synthetic resin, while maintaining advantageous effects as provided by the use of the synthetic resin, thereby making it possible to obtain the sound volume with a smaller key depression energy, and enhance responsiveness of the action. The action part is pivotally moved along with depression of key to thereby transmit key depression energy generated by depression of the key, to a hammer. The action part is formed by a molded article of a thermoplastic resin that is molded by a long fiber process and contains long fibers for reinforcement.

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 action (10) includes a wippen (14) having a wippen body (24). The wippen body (24) is pivotally mountable on a firs rail (20) of a piano. A repetition lever (38) is pivotally mounted on the wippen body (24). A jack (46) is also pivotally mounted on the wippen body (24). A repetition lever spring (48) is interposed between the repetition lever (38) and the wippen body (24) and is pivotally mounted to the repetition lever (38). The repetition lever spring (48) has a first limb (54) which acts on the jack (46) for restoring the jack (46) to its rest position and a second limb (52) which acts on the repetition lever (38) for restoring the repetition lever (38) to its rest position. The second limb (52) is shorter than the first limb (54) such that a free end of the second limb (52) is out of engagement with the repetition lever (38) and is shaped and dimensioned to move together with the repetition lever (38).

Abstract: A hammer sensor includes a photo-filter plate movable together with a hammer assembly and having a base plate fixed to the hammer shank and an arc pattern formed on the base plate and different in transparency from the base plate, a photo radiating element radiating a light beam toward the arc pattern and a photo detecting element disposed on the optical path of the light beam for converting the amount of transmitted light to an electric signal, wherein the photo-filter plate converts the rotational angle of the hammer assembly to the amount of light incident on the photo detecting element, and makes the photo radiating element and the photo detecting element stationary so that a suitable photo-shield case prevents the photo elements from environmental light.

Abstract: 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.

Abstract: A keyboard musical instrument is equipped with solenoid-operated key actuators for guiding a player in fingering on the keyboard, and the solenoid-operated key actuators stop the keys at terminative positions on the way to the end positions, wherein key sensors supplies detecting signal representative of the keys reaching the terminative positions to a controller so that the controller removes the driving signals from the solenoid-operated key actuators immediately before the escape of jacks from the hammers.

Abstract: 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.

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.

Abstract: An acoustic piano is equipped with a shank stopper moved into and out of trajectories of hammer assemblies and a change-over mechanism for changing the shank stopper, and the change-over mechanism has a pedal, a transmitter connected to the pedal and another transmitter held in contact with the transmitter for transmitting force exerted on the pedal to the shank stopper, wherein the transmitters are only restricted in the direction to transmit the force from the pedal to the shank stopper so that the transmitters are independently disassembled and regulable.