Abstract: A sound generation mechanism, provided with a string for generating a vibration sound in response to striking by a hammer, is automatically played in accordance with performance data. The performance data include striking data (note-on event data) for designating timing at which the string should be struck by the hammer, velocity data indicative of an intensity of the striking, and muting data (soft pedal data) for controlling muting. A controller determines drive start timing of the hammer in accordance with the velocity data in such a manner that the string is struck by the hammer at the timing designated by the striking data and performs control such that the drive start timing is advanced in accordance with the muting data. Thus, the string is struck at the striking timing designated by the striking data, but also muting control is performed in accordance with the muting data.

Abstract: A keyboard musical instrument including: a key; a hammer; an actuator configured to drive at least one of the key and the hammer in a movement direction in which the at least one of the key and the hammer moves in a key depression stroke; a hammer detector configured to detect a hammer-motion related value that relates to a motion of the hammer; a trajectory generator configured to generate a target trajectory of the at least one of the key and the hammer based on automatic performance information that defines a motion target value of the at least one of the key and the hammer; a feedback-value generator configured to generate a feedback value based on the hammer-motion related value in automatic performance detected by the hammer detector; and a controller configured to servo-control the actuator based on the generated target trajectory and the generated feedback value.

Abstract: A keyboard apparatus includes a key supported for pivoting movement about a pivot point, a mass member for imparting a reaction force to performance operation of the key in interlocked relation to the key, a transmission member provided in abutment with both of the key and mass member to transmit a load from one of the key and mass member to the other, and an electromagnetic actuator for driving, via a fixed coil, the transmission member toward at least one of the key or mass member. Good key touch feeling can be achieved not only by a load applied from the mass member to the key but also through load control by the actuator. Thus, it is possible to faithfully reproduce a key touch feeling approximate to that in a natural keyboard instrument, such as an acoustic piano, with a simple construction and facilitated control.

Abstract: A keyboard musical instrument has a solenoid including a plunger and a coil into which the plunger is inserted, a drive unit for applying voltage to the solenoid, and a key which moves together with the plunger, and on which a force generated by the solenoid is exerted. The drive unit includes a position detector for detecting position of the key in the direction in which the key is depressed or released. By varying voltage which is to be applied to the solenoid in accordance with the position of the key detected by the position detector while the key is in motion, the drive unit varies the force which is to be generated by the solenoid.

Abstract: While a player is fingering a music tune on a piano, an electronic assistant system monitors the keys to see whether or not the player starts to produce tones through a particular playing technique such as repetition; when the electronic assistant system finds particular key movements unique to the particular playing technique in an early stage, the electronic assistant system decides that the player intends to produce the tone through the particular playing technique, and forces the key to travel on a reference key trajectory in the later stage, whereby the player learns the particular playing technique.

Abstract: A musical instrument comprises a keyboard assembly including juxtaposed keys and juxtaposed swing weight mechanisms, each of the keys correspondingly linked with each of the swing weight mechanisms. The keyboard assembly is supported on a key bed having an aperture which is elongate in the direction of the key juxtaposition. Actuating members are provided corresponding to the respective swing weight mechanisms each of which in turn actuates each corresponding key. The actuating members are disposed in a lower yoke having a channel member and flanges integrally manufactured by bending a metal plate. The flanges are fastened to the key bed across and over the aperture so that the actuating members penetrate the aperture toward the swing weight mechanism. The height of the channel member determines a relative position between the actuating members and the swing weight mechanism.

Abstract: A keyboard device for an electronic keyboard instrument, capable of ensuring stable contact between movable contacts and fixed contacts of a switch body, to accurately detect key depression information. A hammer has a pressure-applying surface formed in a predetermined configuration. A key switch detects key depression information and comprises a substrate with fixed contacts, a hollow switch body with a pressure-receiving surface, and movable contacts provided inside the body. Pressing of the pressure-receiving surface by the pressure-applying surface sequentially brings the movable contacts into contact with the fixed contacts, causing switch body compressive deformation. The pressure-receiving surface and pressure-applying surface are complementary in shape, and an orientation of the former conforms to an orientation of the latter when hammer pivotal motion is terminated after the movable contacts are brought into contact with the fixed contacts.

Abstract: An upright piano is equipped with a soft pedal, and a player makes the hammer stroke shorter by depressing the soft pedal; while a user is reproducing a music tune by means of an automatic player piano fabricated on the basis of the upright piano, the keys are servo controlled on the basis of a position difference of keys between target values and actual values and a key velocity difference, and the duty ratio of driving signal, which is supplied to solenoid-operated key actuators for the keys, are determined on the basis of multiplications between the position difference/key velocity difference and a position gain and a velocity gain; the value of position gain is reduced on the condition that the soft pedal is depressed for preventing the playback from an unintentional loud tone or tones.

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: A method and system for controlling actuators in a mechanical reproducing piano or other instrument. In one implementation, a single finite state machine is provided to control all the actuators. The finite state machine may be or include a shift register or a toggle register, which increases the operating speed. When a note is to be played, the desired dynamic is mapped into a start vector and a stop vector. The actuator is turned on when the state of the finite state machine is equal to the start vector, and is turned off when the state of the finite state machine is equal to the stop vector. Furthermore, the period of the finite state machine is adjusted to be directly proportional to the supply voltage. This allows notes to be played at the desired dynamics even when the supply voltage fluctuates.

Abstract: An upright piano is equipped with a soft pedal, and a player makes the hammer stroke shorter by depressing the soft pedal; while a user is reproducing a music tune by means of an automatic player piano fabricated on the basis of the upright piano, the keys are servo controlled on the basis of a position difference of keys between target values and actual values and a key velocity difference, and the duty ratio of driving signal, which is supplied to solenoid-operated key actuators for the keys, are determined on the basis of multiplications between the position difference/key velocity difference and a position gain and a velocity gain; the value of position gain is reduced on the condition that the soft pedal is depressed for preventing the playback from an unintentional loud tone or tones.

Abstract: An automatic player piano is equipped with solenoid-operated actuators for moving keys in automatic performance without fingering of a human player, and an overheat protector is provided for the solenoid-operated actuators so as to prevent the solenoid-operated actuators from overheat; the overheat protector includes not only a temperature sensor and a rescuer but also an information processor, and a computer program runs on the information processor so as to realize a temperature rise estimator for estimating a solenoid temperature on the basis of the amount of current flowing through the solenoid and an environmental temperature determined through the temperature sensor estimator and an overheat detector so as to find an overheated solenoid, thereby making the rescuer interrupt the current for preventing the solenoid-operated actuator from the overheat.

Abstract: A supporting system is provided on a saxophone for offering assistance to the player, and includes pressure sensors monitoring the touch pieces of the keys, power assisting units equipped with torque motors provided for the keys and a controller connected to the pressure sensors and the power assisting units; a conversion table for depressed touch pieces and another conversion table for released touch pieces are prepared in the controller, and different relations between the finger force and the amount of current to be supplied to the torque motor are respectively defined in the conversion tables, respectively; the amount of current to be supplied is read out from the conversion tables depending upon the increase and decrease of finger force so that the player quickly closes the tone whole with the padded cup without curious key touch.

Abstract: A method and system for controlling actuators in a mechanical reproducing piano or other instrument. In one implementation, a single finite state machine is provided to control all the actuators. The finite state machine may be or include a shift register or a toggle register, which increases the operating speed. When a note is to be played, the desired dynamic is mapped into a start vector and a stop vector. The actuator is turned on when the state of the finite state machine is equal to the start vector, and is turned off when the state of the finite state machine is equal to the stop vector. Furthermore, the period of the finite state machine is adjusted to be directly proportional to the supply voltage. This allows notes to be played at the desired dynamics even when the supply voltage fluctuates.

Abstract: A key actuating system (1) of a keyboard musical instrument is provided which helps quickly push the keys by reducing reaction force with respect to force of pushing the keys during manual operation, and which supports a person having less strength to play the keyboard musical instrument. The key actuating system for a keyboard musical instrument generates a sound when a key (3) is pushed including: a pressure detection sensor (11) detecting a pushing pressure on the key; a status detection sensor (13) detecting a movement status of the key: an actuator (15) actuating the key in a pushing direction of the key; and a control portion (19), when the pressure detection sensor detects the pushing pressure and the status detection sensor detects motion of the key, controls operations of the actuator in order to maintain the detected pressure by the pressure detection sensor at a pressure threshold which is in a range larger than 0 and smaller than a pushing pressure on the key which is necessary for making a sound.

Abstract: A method and system for controlling actuators in a mechanical reproducing piano or other instrument. In one implementation, a single finite state machine is provided to control all the actuators. The finite state machine may be or include a shift register or a toggle register, which increases the operating speed. When a note is to be played, the desired dynamic is mapped into a start vector and a stop vector. The actuator is turned on when the state of the finite state machine is equal to the start vector, and is turned off when the state of the finite state machine is equal to the stop vector. Furthermore, the period of the finite state machine is adjusted to be directly proportional to the supply voltage. This allows notes to be played at the desired dynamics even when the supply voltage fluctuates.

Abstract: An automatic player piano is a combination between an acoustic piano and an automatic playing system, and a grand piano and an upright piano are used as the acoustic piano; the grand piano has action units prompter than action units of the upright piano so that a half-stroke recorded through the grand piano is not reproducible by the upright piano; the automatic playing system causes the hammers to rotate toward the strings without any escape thereby compensating the poor promptness with the short keystroke of the keys until the rotation of hammers.

Abstract: While an automatic player piano is reenacting a music tune, the automatic player piano sometimes fails to miss a tone or tones in a repetition due to a high-speed key movement; a controller searches a music data file for a series of key events expressing the repetition, and makes the key movements uniform without changing the lapse of time from the last key event before the repetition and the lapse of time to the first key event after the repetition so that the automatic player piano is less liable to miss a tone.

Abstract: Key frame has a key support section that pivotably supports thereon a plurality of keys. Hammer structures are pivotably provided in corresponding relation to and below the keys, each of which pivots in interlocked relation to depression operation of a corresponding one of the keys. On a rear portion of the key frame, there is provided an upper stopper that is elongated and extends in a direction where the keys are arranged. The upper stopper defines an upper end limit of pivoting movement of each of the hammer structures. Opening portion is formed between the key support section and the upper stopper. Wiring cable connected to a circuit board, having switches corresponding to the keys, is run below the key support section, then passed through the opening portion and thence drawn upwardly beyond the upper stopper so that it is led out to a region above the upper stopper.

Abstract: A servo controller of an automatic player piano normalizes an actual key position to a value less than a reference value indicative of a target stop on a reference trajectory when the key is found in a region immediately before the target stop and to another value greater than the reference value when the key exceeds the target stop, and adjusts a driving signal to a proper value in such a manner that a solenoid-operated key actuator minimizes the difference between the value or another value and the reference value, whereby the servo controller keeps the key in a narrow region on both sides of the target stop for reproducing stop-and-go key motion.

Abstract: A separate automatic player is independent of a piano, and stands in front of the piano for an automatic playing; the separate automatic player includes a key driver unit, a pedal driver unit and a framework on which the key driver unit and pedal driver unit is carried; the key driver unit has an array of key actuators so as to selectively depress and releases the black and white keys, and a pair of side elevators and a rotary unit is provided between the framework and the array of key actuators; the side elevators bring the plunger heads of the key actuators into contact with the upper surfaces of the black and white keys, and the rotary unit makes the plungers vertical to the upper surfaces so that the key actuators exert force on the black and white keys at the magnitude exactly equivalent to pieces of music data.

Abstract: An automatic player piano is broken down into an acoustic piano and an automatic playing system, and solenoid-operated key actuators are driven to rotate the black/white keys of the acoustic piano; the space between the keyboard and the array of black/white keys is so narrow that the manufacturer provides the solenoid-operated key actuators in the space below the key bed; plunger holes are formed in the rear portion of the key bed, and the solenoids occupy the space under the key bed so that the plungers project through the plunger holes into the space beneath the rear portions of the keys; the key bed is does not lose the mechanical strength so that the tuning work is not frequently required for the key action units.

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: The key actuation system is designed for use with a keyboard instrument of the type having multiple keys. Each of the keys has an upper and lower surface and is pivotally supported above a key bed. A front end of a key may be depressed by a player to play a note. The key bed extends under and is spaced from the lower surface of the key. The actuation system includes an underlever in the space between the lower surface of the key and the key bed, and between the front end of the key in the pivotal support. The underlever has one end that is supported in a stationary position relative to the key bed and another end that is movable towards and away from the key bed. The movable end of the underlever is in mechanical communication with the key such that movement of the movable end of the underlever towards the key bed causes the key to move as if depressed by a player. An actuator is in mechanical communication with the underlever and operable to move the second end of the underlever towards the key bed.

Abstract: A jig is used in an assemblage between key sensors and an acoustic piano, and the jig has a shutter guide assembled with a casing of optical sensor array for aligning slits with target trajectories of shutter plates and pieces of adhesive double coated tape adhered to the shutter plates for aligning the shutter plates with associated white/black keys, wherein the shutter plates are inserted into the slits so that the shutter plates are placed on the target trajectories, and the white/black keys are moved along the target trajectories until they are brought into contact with the pieces of adhesive double coated tape for temporality tacking the shutter plates to the associated white/black keys.

Abstract: A silent automatic player piano calibrates the black/white keys so as to exactly relate a key position signal to the current key positions on the trajectory of the key by itself before a recording so that the key motions are exactly recognized in a recording operation by the silent automatic player piano.

Abstract: A jig is used in an assemblage between key sensors and an acoustic piano, and the jig has a shutter guide assembled with a casing of optical sensor array for aligning slits with target trajectories of shutter plates and pieces of adhesive double coated tape adhered to the shutter plates for aligning the shutter plates with associated white/black keys, wherein the shutter plates are inserted into the slits so that the shutter plates are placed on the target trajectories, and the white/black keys are moved along the target trajectories until they are brought into contact with the pieces of adhesive double coated tape for temporality tacking the shutter plates to the associated white/black keys.

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.

Abstract: A automatic player piano has an acoustic piano with black/white keys selectively fingered by a player, solenoid-operated key actuators selectively energized with driving signals for moving the black/white keys without the fingering, magnetic velocity sensors for detecting current velocities of the plungers of the solenoid-operated key actuators and a controller connected between the solenoid-operated key actuators and the magnetic velocity sensors and changing the magnitude of the driving signals for matching the current velocities to target velocities, and a magnetic shield structure is provided between the solenoid-operated key actuators and the magnetic velocity sensors so as to improve a signal-to-noise ratio of the detecting signals supplied to the controller.

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: An electronic instrument which generates sound using a sound generator upon receipt of a trigger signal. Each pad actuator for generating a trigger signal includes first and second actuators for respectively triggering first and second switches which, upon actuation, generate the trigger signal for the sound generator. The pad actuator is mounted so as to rotate in a first direction about a pivot point upon depression by a user. The first actuator is placed closer to the pivot point than the second actuator and is mounted on a floating cantilever beam such that continued depression of the pad actuator in the first direction after actuation of the first switch by the first actuator causes the first actuator to displace in a second direction opposite the first direction while the second actuator continues to rotate in the first direction about the pivot point until the second switch is actuated by the second actuator.

Abstract: A piano set having automatic playing keys comprises a bracket having a plurality of fixing columns and mounting sockets. A gear set, linkage set of a gear set driven by a motor and connecting shaft of the keyboard are rotationally mounted thereon. The bracket further includes a controlling circuitry which includes a printed circuit board, a battery set, a microswitch and a speaker and which are electrically connected. The keyboard set includes an upper fixing board and a lower fixing board by which a plurality of keys are movably fixed therebetween. Each of the keys is aligned with a driving gear of the connecting shaft. The upper cover is provided with a front recess in which a fallboard is pivotally disposed thereof by means of a fixing plate. The fallboard is provided with a pair of pressing tabs at both sides. When the fallboard is uncovered, those two pressing tabs will trigger on the microswitch such that the motor is powered to drive the gear set and connecting shaft and the connecting rods.

Abstract: A method and apparatus for actuating solenoids in an electronic player piano where a Musical Instrument Digital Interface (MIDI) velocity value is translated to a solenoid driving signal, a counter is activated by the solenoid driving signal, and a solenoid is energized from the counter according to the solenoid driving signal. A central processing unit (CPU) reads the MIDI data from a digital data storage device, and selects the corresponding solenoid driving parameters from a look-up table stored in read only memory (ROM). The solenoid driving parameters are converted into a pulse width modulation (PWM) waveform by a driving circuit containing counters. The PWM signal is sent to the gate of a field effect transistor (FET) switch connected to the solenoid and the solenoid is energized by the FET according to the PWM signal.

Abstract: An automatic player piano records an original key motion reciprocated between a rest position and an end position as a series of a key-on event, a hammer event and a key-off event by using key/hammer sensors, and supplements the key/hammer event for an unusual key motion such as a half stroke, thereby faithfully reproducing the original key motions in a playback mode.

Abstract: In a piano which is enabled to provide performance using electronic sound source as well as normal piano play, the proposed piano is such a piano where there is no difference of balance between the normal piano play and the play using electronic sound source. When key is moved in an electronic sound source mode, CPU detects a number n of the key (S110), detects a time lag .DELTA. T between the timings at which blockage is caused between light emitting elements and light receiving elements of both key sensors (S120), and calculates a velocity V according to the time lag .DELTA. T (S130). Then, performance data is prepared according to these key depression information, at the performance data preparation routine (S140), and a delay time Td corresponding to the velocity V is determined by using a delay time determination table (S150). Subsequently, it is determined whether the delay time Td has elapsed (S160). When it has elapsed, the performance data is outputted to the electronic sound source (S170).

Abstract: An automatic playing apparatus is provided for an acoustic piano for reproducing a music without fingering of a player on a keyboard, and has a pedal actuator unit directly supported by a floor so that a reaction of the pedal is never exerted to the piano case, thereby preventing the key bed from deformation due to the reaction.

Abstract: A plurality of solenoid-operated actuator units are incorporated in an automatic player piano for selectively driving keys in a playback mode, and share two elongated yoke members interdigitated with one another so as to house the solenoid-operated actuator units as close as possible without sacrifice of electro-magnetic forces produced thereby.

Abstract: An electromagnetic actuator unit is provided over a keyboard of a piano, and each of the electromagnetic actuators of the electromagnetic actuator unit has a solenoid coil wound on a bobbin and a plunger for pushing down one of the keys, wherein the gravity exerted on the plunger is smaller than a recovery force of the key or a return spring coupled to the plunger is provided outside of the bobbin for smoothly moving the plunger without influences of the magnetic field produced by the solenoid coil.

Abstract: A computer system connected through appropriate analog and digital circuitry controls or monitors a piano. Solenoids connected to each piano key and to each note-sounding hammer permit a computer program to control the keys and/or the sounding of a note, as well as transmitting to the computer for storage and analysis information concerning a student's performance.

Abstract: A key actuating device of an automatic playing keyboard instrument has a plurality of key actuator units each of which is provided for each of keys arranged above a key bed of a keyboard instrument, preferably between a balance rail and a front rail, and includes a coil or coils provided above the upper surface of the key bed for producing a magnetic field corresponding to a current supplied from outside and passing therethrough in a direction substantially normal to a rocking direction of the key, a plunger fixedly provided on the lower surface of the key, and a yoke or yokes provided fixedly on the coil or coils and opposing the plunger. A relative area of portions of the yoke and the plunger opposing each other or an interval between these portions is variable in the rocking direction of the key and the plunger is not in contact with the coil or or the yoke at any position of the plunger in the rocking movement of the key.

Abstract: An automatic player piano comprises (a) a keyboard provided with a plurality of keys each having a front end portion, an intermediate portion and a rear end portion, the front end portion being pressed by a player for requesting a sound, (b) a key supporting unit provided on a key bed and having a front rail capable of engagement with the front end portion, a back rail capable of engagement with the rear end portion and a balance rail provided between the front rail and the back rail and rockably supporting the intermediate portion, (c) a sound producing mechanism associated with each of the keys and operative to produce the sound, (d) a plurality of key action mechanisms each engagable with the rear end portion of each key and operative to transfer a motion of the key to the sound producing mechanism, and (e) a plurality of key actuator units each provided between the front and balance rails of the key supporting unit and operative to pull down each of the keys for requesting a sound upon activation thereof.

Abstract: For easy adjustment of a key driver assembly, there is disclosed an automatic music player system having at least a recording mode and a reproducing mode and comprising (a) a piano having a keyboard provided with a plurality of keys, a sound generator mechanism operative to mechanically generate sounds when the keys are actuated, and an effector mechanism operative to affect the sound generated by the sound generator mechanism upon actuation, (b) a control unit located at the outside of the piano and operative to store a musical information produced by a keying-in on the keyboard and an operation of the effector mechanism in the recording mode and to produce drive signals based on the musical information stored therein in the reproducing mode, (c) a key driver assembly provided with a plurality of actuators corresponding to the keys, respectively, and responsive to the drive signal for selectively actuating the keys, (d) an effector driver assembly responsive to the drive signal and operative to actuate the e

Abstract: An actuator for an automatic performance piano, includes electromagnetic plunger units provided in correspondence to and adjacent to a plurality of keys of the piano, each of the electromagnetic plunger units having an excitation coil and a plunger, and a key drive portion, provided at the distal end of the plunger for driving the key. The electromagnetic plunger units are arranged along the key arrangement direction to be deviated from each other in the front-back direction of the key in a staggered manner. A motion stroke of the key drive portion of the electromagnetic plunger unit in one row is made smaller than a motion stroke of the key drive portion of the electromagnetic plunger unit in the other row.

Abstract: In a solenoid actuator for use in an automatic performance keyboard instrument of the type comprising a key bed and a plurality of keys mounted on the key bed through seesaw mechanisms, electromagnetic actuators respectively corresponding to the keys and having a common yoke are disposed between the key bed and the keys. Each of the electromagnetic actuators independently actuates the corresponding key. The yoke and the electromagnetic actuators are assembled into a compact unit, thereby being readily incorporated between the key bed and the keys.

Abstract: Electromagnetic devices for actuating piano keys are responsive to music in an encoded format, for example as might be contained on a magnetic tape or phonograph record, to selectively actuate the keys with controlled forces and for selected durations. A separate device is provided for each key, and the devices are operable to authentically reproduce musical renditions. In one embodiment, a single electromagnet is associated with each key rearwardly of the piano headboard, and an energizing signal applied thereto is controlled to determine the intensity and duration of note played. In another embodiment, a plurality of electromagnets are associated with each key rearwardly of the headboard, and are selectively energized to determine the intensity and duration of note played. It is also contemplated to mount various arrangements of electromagnets within a housing, and to place the housing across the front of the keyboard to actuate the keys.

Abstract: There is disclosed an improved mounting plate or rack for mounting a large number of solenoids in a keyboard-actuated musical instrument. The mounting rack is an extruded plate having locking slots formed in the surface thereof and a pair of cooperating actuator alignment ribs on the edges of the planar surfaces of the rack, respectively, one rib for aligning every other actuator and the other rib on the opposite side of the plate for aligning the remaining of the actuators.

Abstract: This is disclosed a mounting assembly for mounting a large number of solenoids in a keyboard actuated musical instrument. An extruded mounting plate or rack has locking slots formed in a surface thereof and cooperating grooves formed in a protrusion or rib. Each solenoid has a frame assembly with oppositely extending flanges, one flange being received in a groove in the projection or rib and the other flange having an off-set screw engaged with a threaded element or fastener in the slots of the rack or bar.