Abstract: A signal processing method according to an embodiment of the present disclosure includes outputting a second sound signal by varying a level of a portion of a band of a first sound signal based on a second parameter corresponding to a displacement of each of a plurality of operators, the first sound signal being identified by a first parameter corresponding to the displacement, the second parameter being different from the first parameter.

Abstract: A keyboard apparatus includes: a key disposed so as to be pivotable with respect to a frame; a first member, an elastic member being disposed on at least a portion of a surface of the first member; a second member configured to be moved on the elastic member while elastically deforming the elastic member in response to pivotal movement of the key; and a hammer assembly connected to the key via the first member and the second member so as to pivot in response to pivotal movement of the key.

Abstract: A keyboard apparatus includes: a key disposed to be pivotable with respect to a frame; a hammer assembly disposed to be pivotable in response to pivotal movement of the key; a first member; a second member disposed to be slid and moved on the first member when the hammer assembly pivots in response to pivotal movement of the key; and a third member connected to the first member and configured to guide the second member such that the second member is not located at a distance greater than or equal to a predetermined distance from the first member, the third member having a shape in which a second contact area that is an area of contact between the second member and the third member is less than a first contact area that is an area of contact between the first member and the second member.

Abstract: A reaction force generator includes a hollow elastic member made of an elastically deformable material and a protrusion protruding from an outer surface of the hollow elastic member, the protrusion being tiltable in at least a first direction and a second direction, the first and second direction being symmetric with each other about a neutral position of the protrusion, wherein at least one of physical dimensions and material properties of the hollow elastic member is asymmetric with respect to the neutral position of the protrusion along the first direction and the second direction such that a first reaction force that would be generated by the protrusion when tilted in the first direction and a second reaction force that would be generated by the protrusion when tilted in the second direction are asymmetric with respect to the neutral position of the protrusion.

Abstract: A keyboard device includes a plurality of transmission members which are displaced in response to a depression operation on each of a plurality of keys and a plurality of hammer members each of which provides an action load to a depressed key by performing a rotating motion in response to the displacement of a transmission member corresponding to the depressed key. The weight of the transmission member is set in accordance with the formation density of a plurality of ribs formed on a transmission body section. Therefore, the weight of the transmission member set in accordance with the formation density of the ribs can be provided to the key as a static load. As a result of this structure, an initial load on a key can be optimized, and a key depressing force on the key at the time of key depression can be favorably transmitted to the hammer member.

Abstract: The monitor device in the disclosure includes a base element furnished with a first face and a second face, a first member, a switch, a second member, and a link member. The first member is disposed on a side of the first face of the base element, enabled to approach toward and separate from the first face. The switch detects whether the first member has approached toward the first face up to a first distance therefrom. The second member is disposed on a side of the second face of the base element, enabled to approach toward and separate from the second face. The link member is connected to the first member such as to cause the first member to approach the first face up to the first distance therefrom, in association with the second member approaching the second face up to a second distance therefrom.

Abstract: A keyboard apparatus, including: a key that is pivotable by depressing and release operations between: a pivotal movement start position corresponding to a non-key depression state; and a pivotal movement end position corresponding to a key-depression end state; a hammer body that is pivotable between: a pivotal movement start position; and a pivotal movement end position for imparting inertia to the key depressing operation; and an elastic portion to apply elastic force to at least one of the key and the hammer body, wherein the elastic portion is configured not to apply the elastic force to the key and the hammer body in the non-key depression state and configured to start to apply the elastic force in a direction toward the pivotal movement start position to the at least one of the key and the hammer body from a certain point in a forward stroke of the key depressing operation.

Abstract: A keyboard device includes hammers 16w, 16b that rock with the rocking movement of plural white and black keys 11w, 11b. The plural white and black keys 11w, 11b include drive units that drive the hammers 16w, 16b. The drive unit is provided on a front end of the key. A positional relationship between a plane including a key support portion of each white key 11w and black key 11b and the front end of the white key 11w and black key 11b, and a top face of each white key 11w and black key 11b is set such that the top faces of the plural white keys 11w and black keys 11b are located on the same plane, when the rocking angles of the plural white keys 11w and black keys 11b reach a predetermined angle respectively.

Abstract: A keyboard device includes plural white and black keys 11w, 11b that rock according to a key depression/release operation. Positions of key support portions 13w, 13b supporting the plural white and black keys 11b, 11w in the longitudinal direction are set to be different from one another. The keyboard device also includes hammers 16w, 16b that rock with the rocking movement of the plural white and black keys 11w, 11b. The plural white and black keys 11w, 11b include drive units 11w1, 11b1 that drive the hammers 16w, 16b. The drive units 11w1, 11b1 and the pivot centers of the hammers are located on the same straight line extending in the lateral direction. An upper-limit stopper 21 and a lower-limit stopper 20, which restrict the rocking movement of the hammers 16w, 16b, are provided to extend in the lateral direction.

Abstract: A keyboard device includes plural white and black keys 11w, 11b that rock according to a key depression/release operation. Positions of key support portions 13w, 13b supporting the plural white and black keys 11w, 11b in the longitudinal direction are set to be different from one another. The keyboard device also includes hammers 16w, 16b that rock with the rocking movement of the plural white and black keys 11w, 11b. The plural white and black keys 11w, 11b include drive units 11w1, 11b1 that drive the hammers 16w, 16b. The pivot centers of the hammers are located on the same straight line extending in the lateral direction. The drive unit 11b1 is located anterior to the drive unit 11w1. An upper-limit stopper 21 and a lower-limit stopper 20, which restrict the rocking movement of the hammers 16w, 16b, are provided to extend in the lateral direction.

Abstract: A keyboard device includes plural white and black keys 11w,11b that rock according to a key depression/release operation. Positions of key support portions 13w,13b supporting the plural white and black keys 11w,11b in the longitudinal direction are set to be different from one another. The keyboard device also includes hammers 16w,16b that rock with the rocking movement of the plural white and black keys 11w,11b. The plural white and black keys 11w, 11b include drive units 11w1, 11b1 that drive the hammers 16w, 16b respectively. The pivot center of the hammer 16b is located posterior to the pivot center of the hammer 16w. An upper-limit stopper 21 and a lower-limit stopper 20, which restrict the rocking movement of the hammers 16w, 16b are provided to extend in the lateral direction.

Abstract: A keyboard device includes hammers 16w,16b that rock with the rocking movement of plural white and black keys 11w,11b. The plural white and black keys 11w,11b include drive units that drive the hammers 16w,16b. The drive unit is provided anterior or posterior to a front end of the key. A positional relationship between a plane including a key support portion of each white key 11w and black key 11b and the front end of the white key 11w and black key 11b, and a top face of each white key 11w and black key 11b is set such that the top faces of the plural white keys 11w and black key 11b are located on the same plane, when the rocking angles of the plural white keys 11w and black key 11b reach a predetermined angle respectively.

Abstract: A keyboard apparatus, including: a key that is pivotable by depressing and release operations between: a pivotal movement start position corresponding to a non-key depression state; and a pivotal movement end position corresponding to a key-depression end state; a hammer body that is pivotable between: a pivotal movement start position; and a pivotal movement end position for imparting inertia to the key depressing operation; and an elastic portion to apply elastic force to at least one of the key and the hammer body, wherein the elastic portion is configured not to apply the elastic force to the key and the hammer body in the non-key depression state and configured to start to apply the elastic force in a direction toward the pivotal movement start position to the at least one of the key and the hammer body from a certain point in a forward stroke of the key depressing operation.

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 pedal device of an electronic keyboard musical instrument comprises a pedal lever swingable according to a depressing manipulation and a reaction force exerting unit for exerting on the pedal lever a reaction force of an amount which depends on an amount of the swing of the pedal lever. The reaction force exerting unit comprises, as an integral unit, a first movable member to be displaced via a thrust rod transferring the swing of the pedal lever, a first urging member which urges the first movable member in a direction to exert the reaction force on the pedal lever, a second movable member to be displaced by the first movable member after the swing of the pedal lever exceeds a predetermined amount, and a second urging member which urges the second movable member in the direction to exert the reaction force on the pedal lever. The first movable member, the second movable member, the first urging member and the second urging member are arranged coaxially around a common axis.

Abstract: A keyboard device for an electronic keyboard instrument, which has a simple construction and can be manufactured at relatively low costs, and is capable of providing let-off feeling closely analogous to the let-off feeling of an acoustic piano. The keyboard device comprises keys, hammers each of which has an engaging part and pivotally moves in accordance with pivotal motion of an associated key, an unmovable holder, and let-off members each formed of an elastic material, for temporary engagement with the engaging part of an associated hammer during each of key depression and key release, to impart let-off feeling to touch feeling of an associated key during key depression. Each let-off member extends from the holder to a pivotal path along which the associated hammer performs pivotal motion, and is compressed during key depression and deflected during key release by engagement with the engaging part.

Abstract: A keyboard apparatus made longitudinally compact while ensuring a pivotal motion range of hammers within a limited space. Common base ends, to which main bodies of white and black keys are connected via vertically extending hinges, are stacked one upon another and fastened to a fastening part of a frame. Hammers are each supported on a hammer pivot shaft such that its rear end is moved upward about the pivot shaft in a key-depression forward stroke. The hammers have their rear ends located forward of rearmost positions of visible parts of black keys. The hammer pivot shafts are located rearward of frontmost positions of the visible parts. A plate portion of the frame, on which key switches are disposed, is located forward of the rearmost positions of the visible parts of the black keys and upward of the fastening part of the frame.

Abstract: Keys of a piano are depressed against the total weight of associated action units and hammers so that balance weight pieces are embedded in the front portion of each key; since the wood bar of the key is expandable and shrinkable due to the conditions of the environment, the weight pieces are liable to come loose; the balance weight piece is formed with ridges and valleys repeated at least 7 times at fine pitches equal to or less than 2 millimeters, and the maximum diameter of the ridges is slightly longer than an inner diameter of a hole formed in the wood bar; while the balance weight piece is being pressed into the hole, the ridges make the inner surface portion elastically deformed; when the balance weight piece reaches the target position, the inner surface portion penetrates into the valleys so that the balance weight piece is lodged therein.

Abstract: In order to detect a state of a key 30, a differential acceleration sensor 38 is provided in addition to a common position sensor 35 and a velocity sensor 36. A reaction force applied by a solenoid unit 20 is determined on the basis of a function which monotonously increases with respect to a differential acceleration signal j in an initial period which is an early stage of depression of a key. After a lapse of the initial period, the reaction force is determined in accordance with velocity, acceleration and the like, referring to a table. As a result, the reaction force rises up rapidly when a key is depressed strongly.

Abstract: In order to improve a touch of a key of a keyboard musical instrument by using a key actuating apparatus which actuates the key supported so as to be rotationally movable with regard to a frame of the keyboard musical apparatus, a key actuating apparatus (1) includes: a plunger (15) which is moved on an arc or curved line in correspondence with a rotational motion of a key (3); and a solenoid (7) including electro magnets (17 and 19) which are fixed to the frame and which are substantially in a cylindrical shape into which the plunger is inserted. The plunger (15) is formed in an arc or curved shape extended in a direction of a rotational motion of the plunger (15). A head end (15b) arranged on the plunger (15) in a lengthwise direction is made from a magnetic body.

Abstract: A plurality of keys are supported at a key support parts such that the respective keys are pivoted by a key-pressing operation of a player in a vertical direction, the keys being arranged in parallel to each other along a width direction of the keyboard device. A plurality of hammers are arranged in parallel to each other along the width direction such that the hammers correspond to the respective keys. The hammers are operatively connected to the corresponding keys to rotate about the respective hammer support parts, the hammers applying inertia to pivoting movements of the corresponding keys.

Abstract: In order to improve a touch of a key of a keyboard musical instrument by using a key actuating apparatus which actuates the key supported so as to be rotationally movable with regard to a frame of the keyboard musical apparatus, a key actuating apparatus (1) includes: a plunger (15) which is moved on an arc or curved line in correspondence with a rotational motion of a key (3); and a solenoid (7) including electro magnets (17 and 19) which are fixed to the frame and which are substantially in a cylindrical shape into which the plunger is inserted. The plunger (15) is formed in an arc or curved shape extended in a direction of a rotational motion of the plunger (15). A head end (15b) arranged on the plunger (15) in a lengthwise direction is made from a magnetic body.

Abstract: A series of adjustable springs, rigidly suspended above the keys of a piano, provides a downward force which reduces the effort needed to depress the keys. Precise adjustment of the series, and its attachment to the piano are facilitated through the use of existing fastener hardware within the conventional piano architecture.

Abstract: Keys of an acoustic piano require balancers for cancellation of a part of self weight of the action units/hammers; however, the balancers are liable to be dropped off due to the aged deterioration of the wooden bars; in order to keep the balancers stable in the keys against the aged deterioration, the balancer is plastically deformed so as to bite into the wooden bar, the balancer, which is formed with thorns, is rotated so as to make the thorns bite into the wooden bar, the balancer is shaped into a configuration different from the holes so as to exert resilient force on the inner surface in a direction in parallel to the grain of wood, or the balancer is inserted into a constricted hole so as to strongly exert the resilient force on the inner surface, thereby being prevented from the dropping off from the keys.

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 plurality of keys are supported at a key support parts such that the respective keys are pivoted by a key-pressing operation of a player in a vertical direction, the keys being arranged in parallel to each other along a width direction of the keyboard device. A plurality of hammers are arranged in parallel to each other along the width direction such that the hammers correspond to the respective keys. The hammers are operatively connected to the corresponding keys to rotate about the respective hammer support parts, the hammers applying inertia to pivoting movements of the corresponding keys.

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: A keyboard structure capable of suppressing a depth dimension of a keyboard instrument and rearward displacements of key main bodies to thereby prevent plastic deformation of hinges. White and black key main bodies are each disposed for pivotal motion around a common base end, serving as a key fulcrum, in a key depression/release direction via a hinge extended therefrom vertically downward. A rear stopper is provided in an intermediate portion of a key frame, and a contact portion of a stopper contact member is in light contact with a front surface of the rear stopper when a key main body is in a key depression initial position. In a key-nondepressed state, when a rearwardly force is applied to a key main body, the rear stopper applies the contact portion with a forwardly force against the rearwardly force, thus suppressing a rearward displacement of the key main body.

Abstract: A tactile or haptic sensation simulation device designed to oppose the movement of a manual control component with a reaction reflecting the movement of the control, where the said device has a chamber containing a magneto-rheological fluid, a mobile element interacting mechanically with the fluid and intended to be linked mechanically to the control component, where the said element is mobile between two predetermined positions, at least one sensor with a cinematic and/or dynamic range that is representative of the movement of the control component, a control component and means for the generation of a suitable magnetic field around the chamber so as to apply a magnetic field that is dependent on the dynamic characteristics to be simulated for the movement of the manual control component, and the real-time measurements, the whole being such that the apparent viscosity of the magneto-rheological fluid varies over the travel of the manual control component.

Abstract: In order to improve a touch of a key of a keyboard musical instrument by using a key actuating apparatus which actuates the key supported so as to be rotationally movable with regard to a frame of the keyboard musical apparatus, a key actuating apparatus (1) includes: a plunger (15) which is moved on an arc or curved line in correspondence with a rotational motion of a key (3); and a solenoid (7) including electro magnets (17 and 19) which are fixed to the frame and which are substantially in a cylindrical shape into which the plunger is inserted. The plunger (15) is formed in an arc or curved shape extended in a direction of a rotational motion of the plunger (15). A head end (15b) arranged on the plunger (15) in a lengthwise direction is made from a magnetic body.

Abstract: A black key for a keyboard instrument, in which a black key cover incorporating a weight can be manufactured at low costs, and the black key cover can be firmly mounted on a key body, in a state stably holding the weight in a black key cover body. A swingable key body extends in a front-rear direction. A black key cover body has a hollow shape opening downward, and is mounted on a front portion of the upper surface of the key body in a manner covering the front portion. A weight is received within the black key cover body. The black key cover body has at least one of lower walls protruding inward from lower portions of left and right side walls, for holding the weight from below. The lower surfaces of the lower walls are bonded to the key body.

Abstract: A tone plate which makes it easy to reduce the entire length and width thereof, thus increasing the degree of freedom in design. The tone plate includes an antinode portion, front and rear ends, and first and second supporting holes which are located closer to the front and rear ends than to the antinode portion and at which a vibration node can be formed. There are provided first and second mass concentrating portions extending toward the front and rear ends from locations on a side close to the first and rear ends with respect to the supporting holes. First and second thinner portions are respectively provided between the antinode portion and the supporting holes. The tone plate vibrates to generate a musical tone of a specific tone pitch when struck with being supported at the supporting holes.

Abstract: The invention relates to a key for pianos, comprising a pivotably supported key body consisting of a soft wood and adjustment means for adjusting the touch load of the key. A plate-shaped element of a different specific weight is inserted into the key body. The position and weight of the plate-shaped element is selected such that a desired touch load of the key is almost accomplished. The weight of the plate-shaped element is varied slightly by inserting an additional weight, in particular a setscrew, or by forming a recess in such a manner that the desired touch load of the key is accomplished. The plate-shaped element consists of a composite wood material comprising a press-formed resin-wood layer formed of wood veneer layers, which are impregnated with a resin under a vacuum and glued to each other while applying pressure and heat to accomplish a very high specific weight.

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

Abstract: In order to improve a touch of a key of a keyboard musical instrument by using a key actuating apparatus which actuates the key supported so as to be rotationally movable with regard to a frame of the keyboard musical apparatus, a key actuating apparatus (1) includes: a plunger (15) which is moved on an arc or curved line in correspondence with a rotational motion of a key (3); and a solenoid (7) including electro magnets (17 and 19) which are fixed to the frame and which are substantially in a cylindrical shape into which the plunger is inserted. The plunger (15) is formed in an arc or curved shape extended in a direction of a rotational motion of the plunger (15). A head end (15b) arranged on the plunger (15) in a lengthwise direction is made from a magnetic body.

Abstract: A keyboard apparatus which is capable of imparting a natural key depression feeling with a definite and positive load change, with a simplified construction. A key touch feeling-imparting mechanism imparts a predetermined key touch feeling to a key when it is depressed. The key touch feeling-imparting mechanism is comprised of a receiving part provided on a support member, and an elastic engaging unit that has one end thereof held by a key operating part of an associated key and another end thereof slidably engaged with the receiving part.

Abstract: A keyboard structure capable of suppressing a depth dimension of a keyboard instrument and rearward displacements of key main bodies to thereby prevent plastic deformation of hinges. White and black key main bodies are each disposed for pivotal motion around a common base end, serving as a key fulcrum, in a key depression/release direction via a hinge extended therefrom vertically downward. A rear stopper is provided in an intermediate portion of a key frame, and a contact portion of a stopper contact member is in light contact with a front surface of the rear stopper when a key main body is in a key depression initial position. In a key-nondepressed state, when a force exerting toward the rear is applied to a key main body, the rear stopper applies the contact portion with a force exerting toward the front against the force applied to the key main body, thus suppressing a rearward displacement of the key main body.

Abstract: An electronic keyboard simulates the keyboard action of one or more acoustic pianos and/or organs. Sensors associated with each key capture the force exerted on the key, the speed of the key and the position of the key to compute an amount of force to apply in feedback to the depressed key. An actuator associated with each key provides the computed feedback value as a counter-force to the player's finger pressure. Feedback may be computed in one or more processors by applying the sensor readings to a system model of the desired instruments mechanical key action. Also, feedback may be determined through a lookup table containing feedback values defining a particular instrument's action. The player can switch between different instrument action definitions as desired, and may tune certain parameters to achieve a customized action.

Abstract: A key is an indispensable component parts of an acoustic or electronic keyboard musical instrument, and key balancers are embedded in the key for varying the moment exerted on the key; the key balancers are fastened to the key by means of an anchor so that the key balancers are neither chattered in nor dropped out from the key.

Abstract: A multiple bit screwdriver comprising a plurality of tool bits, an elongate member defining an axial passage adapted to receive said bits therein positioned tip to end so that the foremost bit operably extends from the passage and is rotatable with the elongate member, first and second retainers connected to the elongate member near each end of the passage and extending radially inward into the passage to engage frictionally the foremost and last bits to prevent said bits from falling out of either end, and a motion restricting member within the passage having an expandable engagement portion that cooperates with at least one tool bit to permit the movement of bits within the passage in one direction only. The engagement portion is expandable in response a tool bit being pushed therethrough in one direction, but resists expanding when a tool bit is being pushed in the opposite direction.

Abstract: A key is an indispensable component parts of an acoustic or electronic keyboard musical instrument, and key balancers are embedded in the key for varying the moment exerted on the key; the key balancers are fastened to the key by means of an anchor so that the key balancers are neither chattered in nor dropped out from the key.

Abstract: There is provided an electric keyboard assembly having a construction which is capable of reducing a height of a keyboard and at the same time facilitating key scaling to key-touch response while maintaining the degree of freedom in designing the keyboard. A key is pivotally moved by a key depressing operation. A seesaw-type mass member having a front extension and a rear extension each extending from a pivot-receiving portion thereof, and a tone-generating position adjustment screw fitted in the front extension is pivotally moved about the pivot-receiving portion by a driving force generated by depression of the key and received via the tone-generating position adjustment screw. The front extension of the mass member pops up to a level higher than the key when the key is depressed. A front weight and a back weight are arranged separately in the front extension and in the rear extension, respectively.

Abstract: An optical sensor array includes plural sensor heads arranged on a supporting plate at intervals for monitoring moving objects such as black/white keys of a composite keyboard musical instrument; the sensor head has resiliently deformable arms on both side portions thereof and a locating hole/guide groove are formed in the reverse surface portion of the sensor head, and an expander, a grip and projections are formed in the supporting plate; when a worker slides the sensor head on the expander, the resiliently deformable arms make the gap wider so that the grip is pinched between the resiliently deformable arms and that the projections are engaged with the locating hole and guide groove, whereby the sensor head is easily fixed to and located at a predetermined position on the supporting plate.

Abstract: An apparatus and method for continuous keyboard system. The Continuous Music Keyboard resembles a traditional keyboard in that it is approximately the same size and is played with ten fingers. It also resembles a fretless string instrument in that it has no discrete pitches; any pitch and any tuning may be played, and finger movements produce smooth glissandi and vibrato. The Continuous Music Keyboard comprises a plurality of rods, each of which has a magnet on each end. The displacement of each rod is measured through mounted Hall-Effect sensors. The sensor values are then analyzed to identify the three-dimensional location of the fingers depressing upon a control surface. Additionally, predictive analysis is conducted on values collected to identify whether a new depression on the control surface has occurred, or rather if a previously placed finger is simply moving alone the Continuous Music Keyboard.

Abstract: An operation apparatus is responsive to a physical action for inputting a control parameter of a musical sound into an electronic musical instrument. The operation apparatus is provided with a plurality of movable members individually responsive to the physical action to undergo a reciprocal movement. A frame mounts the plurality of the movable members in aligned manner. A tension member having a length is supported at both ends thereof by the frame to extend along the movable members such that each movable member may come into contact with the tension member during the course of the reciprocal movement of each movable member. A detector is connected to the tension member for detecting a deflection of the tension member caused by the contact of the movable member, and generates a signal corresponding to the detected deflection as the control parameter.

Abstract: A key is provided for permitting simple attachment of a weight and easy adjustment of a touch load, while using an alternative material for substitution for lead as a material for the weight, to thereby reduce the manufacturing cost. A swingable key body is formed with an embedding hole. The weight is made of a composite material produced by blending a plurality of kinds of materials except for lead in a predetermined blending proportion to have a predetermined specific gravity, and is removably attached to the embedding hole of the key body.

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 keyboard musical instrument includes an acoustic piano for generating acoustic tones, a silent system for rebounding the hammer assemblies between the escape from the key action mechanisms and strikes against strings and automatic playing system for actuating the key action mechanisms without fingering, and the automatic playing system generates electronic tones on the basis of the key motions monitored by associated key sensors, wherein the space between the rest position and the end position is divided into plural sections, and a controller calculates a key velocity in each of the plural sections so as to exactly determine the key motion, thereby improving the fidelity of the electronic sounds to the key motion.

Abstract: An in-line keyboard provides a large number of music producing actuators in a small space. Each actuator corresponds to a note on a musical scale. The actuators are arranged in perpendicular columns and rows. The actuators of each column are played by a single finger. The actuators corresponding to natural notes have a first tactile feel, such as cylindrical. Actuators corresponding to sharp and flat notes have a different tactile feel. The actuators corresponding to the sharp and flat notes are arranged in columns between the columns of the natural note actuators. The natural notes are further arranged such that pairs of adjacent actuators in a column correspond to perfect fifths of a musical scale.

Abstract: A method for eliminating or reducing noise created by the action mechanisms of piano keys during its return stroke after striking a string, by regulating the amount of time for the mechanism to return to rest. The method comprises the steps of sequentially initiating a pair of braking pulses by the actuator solenoid to slow the action mechanism during its return stroke. Each braking pulse is of a specified duration and magnitude such that the mechanism's return time is maximized while eliminating the possibility of double hits on the string.