Abstract: A stopper, a driver unit, key and pedal sensors, a sound processing unit and a sound system are installed in an acoustic piano so as to remodel the acoustic piano into a keyboard musical instrument performable with either acoustic or electronic sounds.

Abstract: A drum pedal system for independently actuating two drum beaters. In one embodiment, the pedal is split into a toe and a heel portion, each independently connected to a beater oriented adjacent a drum head. The drummer may independently actuate one or both beaters.

Abstract: A keyboard musical instrument is a compromise between an upright piano and an electronic keyboard, and a hammer stopper is provided between hammer shanks and sets of strings; the hammer stopper has cushion members on a stopper rail where the hammer shanks rebound before a strike against the strings, and a pair of parallelogram crank mechanisms are connected to both end portions of the stopper rail so as to project the cushion members into and retract them from the trajectories of the hammer shanks, thereby decreasing space occupied by the cushion members.

Abstract: A knuckle assembly for an escapement action of a piano includes a knuckle, a jack retainer, and an adjustment means acting between the retainer and the knuckle for positioning the retainer relative to the knuckle. The knuckle assembly is mountable between first and second ends of a hammershank. The knuckle defines a knuckle surface for engagement with a jack. The knuckle is arranged for escape of the jack from engagement with the knuckle surface during depression of a piano key. The retainer retains the jack in an "at rest" position with the jack in engagement with the knuckle surface in opposition to force of a spring urging the jack toward the "at rest" position. A piano escapement action assembly includes a hammershank, a knuckle assembly, a jack engaged with a knuckle surface in an "at rest", and a spring disposed to urge the jack toward the "at rest" position.

Abstract: An automatic player piano prolongs acoustic sounds in playback as if a player pushes down a sostenuto pedal, and a controller is responsive to a first piece of music data information representative of key-on state, a second piece of music data information representative of key-off state, a third piece of music data information representative of pedal-on state and a fourth piece of music data information representative of pedal-off state so as to play a tune by using key actuators associated with the keys; when the first piece of music data information is supplied to the controller for a key, the controller instructs the key actuators to change associated the key from the key-off state to the key-on state; when the second piece of music data information is supplied to the controller without the third piece of music data information for a key, the controller instructs the key actuator to change the key from the key-on state to the key-off state; when the second piece of music data information is supplied to the

Abstract: a stopper, a driver unit, key and pedal sensors, a sound processing unit and a sound system are installed in an acoustic piano so as to remodel the acoustic piano into a keyboard musical instrument performable with either acoustic or electronic sounds.

Abstract: In order to give piano-like key touch to a player in an electronically sound producing mode, a keyboard incorporated in a musical instrument is linked with key action mechanisms associated with hammer mechanisms, and a stopper blocks the hammer shanks before the hammers strike the strings so that noises are not mixed with synthesized tones.

Abstract: A keyboard for an electronic instrument and an electronic piano providing a key touch and a key touch response similar to those of an acoustic piano and stabilizing the key touch response for each key. Two detection positions of a key stroke are detected by a jack tail sensor or a jack sensor by detecting contact of a jack tail equivalent member or a jack equivalent member, before or after a hammer equivalent member disengages from or releases from a jack equivalent member. A time difference between the two positions is not adversely affected by the let-off of the jack equivalent member. Therefore, the positions and the time difference are detected stably for each key. Sound timing and sound intensity are controlled based upon the detected positions and time difference between the positions. Therefore, a key touch response, similar to that of an acoustic piano, can be stably obtained for each key.

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 keyboard musical instrument has an acoustic piano, an electronic sound generating system, a rotary stopper for preventing sets of strings from impacts of hammer heads and regulator for changing distances between regulating buttons and toes of jacks, and a link mechanism connects a pedal and both of the rotary stopper and the regulator so as to concurrently change the rotary stopper and the regulator between an acoustic sound mode and a silent mode.

Abstract: A keyboard musical instrument selectively generates acoustic sounds and electronic sounds depending upon a mode selected by a player, and has a hammer stopper for interrupting hammers before strikes at strings and an escape accelerator for accelerating an escape of a jack from the hammer assembly in the silent mode earlier than an escape in the acoustic sound mode, thereby preventing the hammer assembly from capture between the jack and the hammer stopper without deterioration of the piano key touch.

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: In a piano mechanism, the sound volume can be effectively controlled without changing the feel of the key or tone quality. A hammer regulating button projecting from a hammer rail contacts the upper face of a catcher just before a hammer strikes a string. By restricting the string striking movement, the volume of string striking sound is controlled, irrespective of the mechanical operation of a jack or other associated transmitting components responsive to the key depressing. No cushioning material is required between hammer and string. In a piano having an electronic sound source built therein, even when the keys are depressed, the hammer can be stopped from striking strings by the provision of a hammer shank stop rail and a catcher regulating button. Therefore, without generating a string striking sound, sounds are generated from the electronic sound source. By manually turning an adjusting screw of the catcher regulating button, the position of the hammer when stopped can be adjusted.

Abstract: An escapement action for a piano includes a hammershank having a first end mounted to pivot relative to the piano and a second end carrying a hammer to strike a tensioned string of the piano, with a knuckle disposed therealong between the first and second ends. A repetition support bearing against a key of the piano is mounted to pivot relative to the piano in response to depression of the key. A jack has a first portion extending from a pivot connection with the repetition support and defines a jack surface disposed for engagement with a knuckle surface, the jack arranged for escape of the jack surface from engagement with the knuckle surface during depression of the key. A spring urges the jack toward an "at rest" position with the jack surface in engagement with the knuckle surface. A jack retainer assembly dependent from the hammershank between the second end and the knuckle includes a cushion surface positioned to retain the jack in "at rest" position in opposition to force of the spring.

Abstract: On a keyboard musical instrument provided with action assemblies each including a catcher and silent assemblies each including a stopper, the real silent distance between each catcher and an associated stopper is measured to calculate its difference from the optimal silent distance, and one or more attachments are added to or one or more components are removed from either of the two elements depending on the polarity of the difference in silent distance in order to minimize the let off distance of each hammer relative to an associated string.

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 instrument selectively enters into an acoustic sound mode for performing a music with acoustic piano sounds and an electronic sound mode for performing a music with synthetic sounds, and a rotary stopper is provided between hammer shanks and strings for interrupting a rotation of the hammer toward the strings in the electronic sound mode; wherein a cushion is provided on the rotary stopper for damping an impact of a damper leaving from the strings in both acoustic and electronic sound modes so that a player can perform a music without a noise.

Abstract: A keyboard instrument selectively enters into an acoustic sound mode for producing piano tones and into an electronic sound mode for producing synthetic tones, and comprises an acoustic piano, an electronic sound generating system and a mode controlling system, wherein the mode controlling system has a stopper slidable along strings of the acoustic piano so that the strings are struck by or blocked from hammers of the acoustic depending upon the position of the stopper.

Abstract: A hammer stopper is moved into and outof an orbit of an extension of a hammer shank depending upon an operation mode, and the extension rebounds on the hammer stopper in an electronic sound producing mode between an escape of a jack from a butt and a strike of a hammer head at a set of strings so that a player performs a music through synthesized sounds without sacrifice of the piano key-touch.

Abstract: In order to give piano-like key touch to a player in an electronically sound producing mode, a keyboard incorporated in a musical instrument is linked with key action mechanisms associated with hammer mechanisms, and a stopper blocks the hammer shanks before the hammers strike the strings so that noises are not mixed with synthesized tones.

Abstract: A key action mechanism incorporated in an upright piano is accompanied with a repetition mechanism having a repetition lever rotatably supported by a butt and pushed by a jack after an escape from the butt for producing a gap between a leading end thereof and a back check, therefore, the butt and, accordingly, hammer assembly can rotate backwardly over a predetermined angle due to the gap, after the striking or after the escape of the jack, and, as a result, the hammer assembly is prevented from double-strike.

Abstract: In a striking mechanism (1) for a piano, grand piano, or similar string instrument the power for the key (8a) is transferred to the hammer (3) via a rod system (10, 11, and 12) so adapted that the connection of the key (8a) and the hammer (3) is never interrupted. The rod system (10, 11, and 12) is supported during the striking movement against deflection by a first guide boss or roller (18) supported by a first curve guide (19), and during the return movement by a second guide boss or roller (20) supported by a second curve guide (21). The first curve guide (19) can swing between a first, advanced position in which it is releasably locked by a locking pawl (28) and the rod system is capable of causing the hammer (3) to touch the string when the key (8a) is pressed down, and a released second retracted position in which this is no longer possible. This ensures that the hammer (3) is withdrawn so rapidly after having struck the string (2) that the string can vibrate freely and deliver its note.

Abstract: An automatic performance device for a keyboard instrument such as piano, organ, cembalo and celesta includes operators such as keys and a pedal provided in a keyboard instrument for producing sounds, a target performance state designation unit for producing target performance information of the keyboard instrument, a real performance state detection circuit for detecting an operation state of the operators and producing a detection output, an actuator such as a solenoid for actuating the operators, and a control circuit for controlling the actuator. The control circuit detects in error between the detection output of the real performance state detection circuit and the target performance information, and generates an operator actuating signal by correcting the target performance information to eliminate the error and supplies the corrected operator actuating signal to the actuator.

Abstract: A muting device of an upright piano which includes butt, a wippen, a capstan button and a muting mechanism (15). This butt rotates with a hammer which strikes a string of the upright piano. In addition, a jack is provided to come in contact with a lower surface of the butt, and rotates the butt in response to displacement of the key. The jack is supported by the wippen such that it can freely rotate. The capstan button is provided at a back edge portion of the key to transmit displacement of the key to the wippen. The muting mechanism is designed to reduce a string-striking stroke by rotating the hammer. Further, there is provided a key-displacement-transmission-rate changing mechanism. When reducing the string-striking stroke by the muting mechanism, this mechanism raises a displacement transmission point, at which displacement of the key is transmitted to the wippen, toward a rotation center of the key from the capstan button.

Abstract: A key striking force sensor suitable for player pianos.This sensor contains a displacement sensor for measuring displacement between the displacement sensor itself and a catcher which rocks together with a hammer. As the positions of the catchers corresponding to the hammer respectively are almost the same, plural of the displacement sensors can be mounted on a common circuit board. Accordingly, mechanical construction thereof is comparatively simpler than that of conventional player pianos.

Abstract: An improved wippen heel arrangement for an upright piano includes: a pillar screwed into one end portion of a piano key so that the projecting length of the pillar which projects from the piano key is adjustable; a wippen heel attached to a wippen constituting one element of an action mechanism; and a wippen joint interposed between the pillar and the wippen heel for pivotal movement about a stationary shaft, in which the thrust applied to the pillar is transmitted through the wippen joint to the wippen. Accordingly, a key touch quality which may be experienced with a grand piano can be enjoyed using an upright piano.

Abstract: In construction of a key musical instrument such as a piano, a swingable element such as a hammer is accompanied with a pneumatic damper having an air vent so that, when impulsive load is applied by motion of the swingable element, fluid viscous resistance caused by flow of air in the pneumatic damper well absorbs shock, thereby greatly suppressing undesirable bound of said swingable element on return to its initial rest position.

Abstract: A portable electric keyboard musical instrument is disclosed which includes a plurality of sound producing elements with each fixedly attached to the supporting structure, and a plurality of actions for selectively causing respective elements to vibrate. Each action is supported on the supporting structure and associated with one of the elements. Each action also includes a hammer assembly for selectively striking one of the reeds and an escapement assembly for initiating the striking action of the hammer associated therewith and to control its motion thereafter until reactivated. A plurality of keys are provided each associated with one of the actions for actuating its hammer assembly so as to strike its respective element. The action is a modified Viennese action characterized in one particular by the elimination of a pin axle and by the use of a resilient hinge.

Abstract: A portable electric keyboard musical instrument is disclosed which includes (1) a two-part folding supporting structure, (2) a plurality of vibratile reeds with each having an end fixedly attached to the supporting structure, and (3) a plurality of actions for selectively causing respective reeds to vibrate. Each action is supported on the supporting structure and associated with one of the reeds. Each action also includes a hammer assembly for selectively striking one of the reeds and an escapement assembly for initiating the striking action of the hammer associated therewith and to control its motion thereafter until reactivated. A plurality of keys are provided each associated with one of the actions for actuating its hammer assembly so as to strike its respective reed. A pickup device is used in spaced relation to the reeds for generating an electrical frequency from the vibrations of the reeds.

Abstract: In the construction of a damper assembly of pianos, the conventionally used long-sized damper wire is replaced by a pair of separate short-sized lever components operationally related to each other via an additional intermediate damper lever for stabilized action of the assembly even without provision of the conventionally used guide rail. A shorter length damper wire joins the upper lever component to the damper head.

Abstract: A keyboard musical instrument utilizes a magnetic action to strike a resonator element with a hammer in response to playing of a pivotally mounted key, the magnetic action including a pair of opposite polarity magnetic poles mounted on an actuating end of the key and a magnetic pole mounted on the hammer to be disposed in horizontal alignment with one of the poles mounted on the key of an opposite polarity when the hammer is in a rest position such that the opposite polarity magnetic poles attract one another with the hammer in the rest position and, when the playing end of the key is depressed, the similar polarity pole on the actuating end of the key is moved to repel the magnetic pole carried on the hammer to impel the hammer to strike the resonator element. A block of non-magnetic material can extend from the lower magnetic pole on th actuating end of the key under the magnetic pole of the hammer to engage the same and initiate movement of the hammer when the playing end of the key is depressed.

Abstract: An action for a piano type musical instrument in which the hammer striking force is produced by the reaction of a pneumatic piston. For the grand piano embodiment, the hammer pivot is carried by the key-lever and the piston is connected to the hammer butt such that when the instrument is played the resistance of the piston raises the hammer into the musical string. A similar action is shown for the upright piano. In each case the hammer is propelled into the string with a velocity proportional to key-lever velocity and the escape, check and repetition parts of conventional actions are made unnecessary by the inherent properties of the pneumatic piston.

Abstract: Disclosed is a modified striking mechanism for use in pianos and related instruments having strings or their equivalent to produce musical notes and keys to select the notes. The mechanism includes a hammer assembly, a lever driving the hammer, coacting gear means for imparting motion to the hammer and features a novel escapement action for use therewith. Additionally disclosed are improvements including an escapement action adapted for use with conventional piano striking mechanisms, a novel damper assembly, a mechanism for activation by the soft pedal of the piano, a tension adjustment mechanism for varying the amount of force necessary to strike a key, and novel balance rail and capstan lever assemblies.

Abstract: A toy piano has a set of sound-producing elements disposed within a frame, and a set of key-shaped levers pivotably supported on the frame along a normally horizontal axis for movement from a first position to a second position, respectively. A set of hammers is pivotably disposed within the frame for striking the sound-producing elements; the hammer-contacting ends of the levers normally rest on the hammers, respectively, for preventing the release thereof. The sound-producing means are actuated either manually by depressing one of the levers and releasing it thereafter so that a corresponding hammer is then made to impinge on one of the sound-producing elements, or automatically when a cam-shaft is permitted to periodically strike at least one of the released hammers.