Abstract: In a keyboard apparatus including a key supported for pivoting movement about a pivot point, a mass member that imparts a reaction force to performance operation of the key in interlocked relation to the key, and an electromagnetic actuator provided between the key and the mass member for imparting a driving force to the key and mass member, a transmission member is provided in detachable abutment with the key and mass member. The transmission member can be disengaged from the key or the mass member depending on operating conditions of the key and the mass member. Thus, it is possible to not only prevent unnecessary binding forces from acting in areas where the transmission member and the key and the mass member abut against each other, but also achieve smooth movement of the key and the mass member and prevent increase of inertial mass of the transmission member. The smooth movement of the key and mass member can achieve force sense control with good responsiveness.

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: 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 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: In order to realize a small and light key actuating apparatus for actuating a key which is rotatably supported with respect to a frame, a key actuating apparatus (7) is provided which includes a polymer transducer (9) for rotatably moving the key (3) by using a deformation of the transducer, wherein the transducer which is substantially formed in a plate shape includes: a polymer film (15) which is dielectric and made from an elastically deformable polymer material; and a pair of electrodes (17) arranged at both sides of surfaces of the polymer film, and the transducer is deformed corresponding to switching between an application of voltage and a lack of voltage between the electrodes.

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 driving apparatus for driving a key may include, but is not limited to, a first elastically deformable unit. The first elastically deformable unit is configured to receive a first control voltage. The first elastically deformable unit is configured to show elastic deformations of stretch and shrinkage based on the level of the first control voltage. The first elastically deformable unit is configured to allow the key to be driven by the elastic deformations of stretch and shrinkage of the first elastically deformable unit.

Abstract: An automatic playing system is independent of acoustic pianos, and is designed to perform music tunes expressed by sets of MIDI music data codes on the acoustic pianos; since the acoustic pianos have their own individualities, control parameter table, which were prepared through experiments on a standard piano, are not optimum for most of the acoustic pianos due to the individualities: the automatic playing system can tailor the control parameter tables defining relation between the magnitude of driving signal and the MIDI velocity and relation between the magnitude of driving signal and time lag from the supply of the driving signal and the collision between the hammers and the strings for each sort of acoustic pianos before the automatic playing so that the automatic playing system reproduces the music tunes at high fidelity regardless of the sort of acoustic pianos.

Abstract: The invention relates to an arrangement, with which pressure point characteristics can be simulated, such that a key stroke typical of a cembalo, as well as the key characteristics of an organ can be as near as possible approached and permits the replication of a dynamic key stroke, as well as multiple pressure points during a single key operation. At least one sensor (3) is rigidly arranged for each key (1), from which positional data, about the key, is sent to an analog signal preparation unit and a programmable analytical unit (6), which generates data for an externally connected digital signal processor (7). Each key is coupled to an electromagnet (2), which is controlled by the analytical unit, depending upon the positional data and a current program. The arrangement for the creation of pressure points in keyboards is suitable for piano-like electronic keyboard instruments, electronic cembalos and electronic organs.

Abstract: An automatic player piano controls keys to be rotated by solenoid-operated actuator units in such a manner as to pass a reference point on a trajectory of the key at a reference velocity in a playback mode, and a hammer driven by the depressed key strikes strings at the same intensity as that in a recording mode, because the intensity is variable with the reference velocity at the reference point.

Abstract: An automatic performing apparatus that executes recording and reproduction of a performance includes a diagnostic signal generator for sending a power supply control circuit at least one of normal and abnormal diagnostic signals indicating whether a controller is normally executing a program. The power supply control circuit controls the power supplied to a drive circuit by interrupting the power or reducing the power to such a low level that the drive circuit is not damaged by a prolonged power supply if the operation of the controller is determined abnormal based on the diagnostic signal generated by the diagnostic signal generator.

Abstract: An improved combination acoustic-mode and electronic-mode piano is provided which includes a hammer shank stop rail that intercepts the hammer shank, when in the electronic mode, so that the hammer cannot complete its normal travel and cannot strike its corresponding string(s) when its piano key is actuated. The hammer shank stop rail is actuated by an intermediate crank that, in turn, is actuated by a pedal dowel attached to one of the pedals of the piano. When operated in the acoustic mode, the stop rail occupies a position that will not interfere with the hammer shank's movements, and when in the electronic mode, the stop rail intercepts the hammer shank so that its associated hammer will not be able to travel all the way into contact with their associated string. A second embodiment operates the stop rail by use of a cable and cam mechanism. A third embodiment uses a hand-actuator to operate the stop rail via a dowel and intermediate crank.

Abstract: An automatic player piano is implemented by a combination of an acoustic piano and an automatic playing system, and a velocity feedback loop and an acceleration feedback loop control solenoid-operated key actuator units for reproducing a performance so that the acceleration feedback loop cancels the undesirable increment of the resistances of the solenoid coils and aged deterioration.

Abstract: A solenoid drive system enabling an automatic performing apparatus to control the intensity of key depression with respect to individual keys. Voltage waveform data is provided for each of the solenoids to drive an associated keys. One cycle of the voltage waveform data is divided in a predetermined time period into a predetermined number of bit segments. A value of "1" or "0", representing a pulse height level of the control signal for each respective key is written to each and every bit segment. Duty cycle of the square wave of each of the control signals can be thus precisely varied according to and to match the key depression intensity. The voltage waveform data may be written to sequential addresses in the memory, and read out from non-sequential addresses in the memory. Alternatively, the voltage waveform data may be written to non-sequential addresses in the memory and read out from sequential addresses in the memory.

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: There is disclosed a method and apparatus for reducing the power required to activate the soft and playing mechanism of an electronic player piano and similar instruments. In accordance with the invention, full voltage on the solenoid is maintained for a short period of time which is more than sufficient to allow full travel of the solenoid and then the power is reduced by reducing the applied voltage. In accordance with the preferred embodiment, a timer is started when the solenoid is commanded on and then when the timer times out, the command gate signal is turned on and off with a waveform which can be set at a duty cycle sufficient to maintain the solenoid in the held-in position.