JPS6329267B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an automatic piano performance device, and in particular,
The present invention relates to a solenoid driving method for driving a key driving solenoid provided for each key of a piano.

In an automatic piano performance device, it is necessary to drive a key drive solenoid provided for each key in a state similar to that of an actual human key touch. FIG. 1 is a diagram showing an example of a conventional solenoid drive waveform. In this figure, symbol A is attack data necessary for the plunger of the solenoid to escape from static friction, and B is data for keystroke strength (keystroke strength) for the solenoid plunger. Touch data for driving the plunger at a speed corresponding to command data) and C are holding data necessary for holding the plunger in a driving state (protruding state). Here, the level and time width of the attack data A are constant, the level and time width of the touch data B change according to the keystroke strength data, and the hold data C is
The level is constant, but the time width changes depending on the key-on time. Although this figure shows an analog waveform, in reality, the solenoid is often driven by a pulse signal having a duty ratio corresponding to each level shown in the figure.

By the way, in such a conventional solenoid drive waveform, the time width and level of attack data A are constant regardless of the keystroke strength data, and the waveform has a steep rise, so the value of the keystroke strength data is particularly When the pitch is small (that is, when the sound is weak), there is a disadvantage that the actual key touch by a person and the movement of the plunger are different from each other.Furthermore, since the rise is steep, the tip of the plunger comes into contact with the key. The drawback was that mechanical noise was generated during operation. Note that this mechanical noise naturally occurs when there is a strong sound, but in this case it is not a practical problem because a loud sound is generated from the piano at the same time.

In view of the above circumstances, this invention provides a piano that can drive the plunger of a solenoid in an operating state that is closer to the actual touch of a key by a human, and that can prevent mechanical noise that occurs when the tip of the plunger contacts a key. The present invention provides a method for driving a solenoid in an automatic musical performance device, and is characterized in that the solenoid is driven by a signal having a rising portion in which the energy increases sequentially as time passes.

An embodiment of the method according to the present invention will be described below with reference to the drawings. FIG. 2 is a block diagram showing the configuration of the same embodiment. In this figure, reference numeral 1 is a circuit that outputs a key-on signal KON (see Fig. 3 A) indicating the drive timing of the piano key 2 and key-stroke strength data KD indicating the key-stroke strength, and the output key-on signal KON The keystroke strength data KD are supplied to the solenoid drive circuit 3. The solenoid drive circuit 3 is a key-on signal
Based on KON and keystroke strength data KD, a solenoid drive signal P consisting of attack data A, touch data B, and hold data C that changes in two stages as shown in FIG. 3B is created and output to solenoid 4. do. In this case, attack data A is data for the plunger 4a of the solenoid 4 to escape static friction, touch data B is data for driving the plunger 4a at a speed according to the keystroke strength data KD, and retention data C is data for the plunger 4a to escape from static friction.
This data is for holding the data in a protruding state, and includes level data D ₁ , D ₂ and time data T ₁ , T ₂ of attack data A, and level data of touch data B.
D ₃ and time data T ₃ are each keystroke strength data KD
It is starting to change depending on the situation. In addition, the third
Although the signal P is shown as an analog waveform in FIG. 9, the signal P is actually a pulse-modulated signal as described below.

The solenoid drive circuit 3 will be explained in more detail below. When supplied with the key-on signal KON and the keystroke strength data KD, the solenoid drive circuit 3 first outputs the keystroke strength data KD to the attack data memory 5 and the touch data memory 6, respectively. The attack data memory 5 stores in advance a set of level data D ₁ , D ₂ and time data T ₁ , T ₂ of the attack data A shown in FIG. 3B, corresponding to various keystroke strength data KD. It is a memory, and the keystroke strength data is stored from the solenoid drive circuit 3.
When KD is supplied, the supplied keystroke strength data
Level data D ₁ , D ₂ and time data corresponding to KD
T ₁ and T ₂ are each output to the solenoid drive circuit 3.
Similarly, the touch data memory 6 is a memory in which sets of level data D ₃ and time data T ₃ of the touch data B are stored in advance in correspondence with various keystroke strength data KD. When strength data KD is supplied, level data D ₃ corresponding to the supplied keystroke strength data KD
and outputs time data _T3 to the solenoid drive circuit 3. The solenoid drive circuit 3 receives level data _D1 to _D3 and time data _T1 to _T3 supplied from the attack data memory 5 and the touch data memory 6.
are stored in respective internal registers. Next, a pulse signal having a duty ratio corresponding to the level data _D1 is generated and outputted to the solenoid 4 as a signal P. Also, from this point on, measurement of time corresponding to time data _T1 is started. Then, when the time data T ₁ has elapsed, the level data
Generate a pulse signal with a duty ratio corresponding to D ₂ and output it to the solenoid 4 as a signal P,
Also, from this point on, time measurement of time data _T2 is started. Then, when the time of the time data _T2 has elapsed, a pulse signal having a duty ratio corresponding to the level data _D3 is outputted as the signal P, and from this point on, the time of the time data _T3 is measured. Then, when the time of time data T ₃ has elapsed, a pulse signal having a duty ratio corresponding to the level data D ₄ (see the third reference) stored in advance is generated, and the signal P is sent to the solenoid 4. Output to. And the key-on signal
Signal P (pulse signal) when KON is turned off
is off.

Thus, in the embodiment shown in FIG.
The attack data A is data that increases in two stages, and the level data D ₁ , D ₂ and time data T ₁ , T ₂ of the attack data A can each be changed according to the keystroke strength data KD. ing. Therefore, the plunger 4 of the solenoid 4
It is now possible to control the activation operation of the plunger 4a more finely than before, and as a result, it is possible to make the activation operation of the plunger 4a more similar to a human key touch. It is also possible to prevent mechanical noise when the tip comes into contact with the key 2. FIG. 4 shows an example of attack data A that changes depending on the keystroke strength data KD. Figure A shows the case of a strong tone (the keystroke strength data KD is large); in this case, the level data D ₁ and D ₂ are both "10", and the time data T ₁ and T ₂ are both 4 msec. Further, FIG. 4B shows the case of a medium tone, in which the level data D ₁ and D ₂ are "5" and "10", respectively, and the time data T ₁ and T ₂ are both 4 msec. Further, C in the figure shows a case of a weak tone, in which the level data D ₁ and D ₂ are "2" and "5", and the time data T ₁ and T ₂ are both 12 msec.

As the attack data A, for example, data that rises sequentially in multiple stages as shown in FIG. 5A may be used, or data that rises smoothly in sequence as shown in FIG. Further, as the signal P for driving the solenoid 4, an analog signal may be used instead of a pulse signal.

As explained above, according to the present invention, the solenoid is driven by a signal having a rising edge whose energy increases sequentially with the passage of time, so that the solenoid plunger is driven in an operating state closer to that of a human key touch. In addition to being able to drive the plunger, it is also possible to prevent mechanical noise when the tip of the plunger comes into contact with the key.

[Brief explanation of the drawing]

FIG. 1 is a waveform diagram showing an example of a conventional solenoid drive waveform, FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. A waveform diagram showing the waveform of the drive signal P, FIGS. 4A to 4C are waveform diagrams showing the waveform of the attack data A that changes according to the keystroke strength data KD, and FIGS. 5A and 5B are other examples of the attack data A. FIG. 2...Key, 3...Solenoid drive circuit, 4...
...Solenoid, 5...Attack data memory.

Claims (1)

[Claims] 1. A solenoid driving method for driving a solenoid provided for each key of a piano, characterized in that the solenoid is driven by a signal having a rising portion in which energy increases sequentially over time. .