JPH0419795A - Key of automatic keyboard musical instrument - Google Patents

Abstract

PURPOSE:To improve the mounting performance of an actuator by cutting and forming a recessed part in the reverse surface of a key and embedding an upper yoke in the recessed part. CONSTITUTION:The cut part 17 is formed at the upper yoke fitting position of the key 11 used for the automatic keyboard musical instrument which drives the key according to electric power supplied to a coil and the upper yoke 15 is embedded and fixed in the cut part 17. This cut part 17 facilitates the position of the upper yoke 15 to improve its mounting performance, and when the actuator is mounted below the key, the space is increased substantially to obtain the space for the coil 16, thereby reducing the heating loss of the coil 16.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a key for an automatic keyboard instrument, in which a recess is formed by cutting out the back surface of the key, and an upper yoke is buried in this recess, whereby an actuator can be operated. This improves the ease of implementation.

<Prior Art> Conventionally, there has been an automatic keyboard instrument, such as a player piano, configured as shown in FIG. 7, which can be played by an actuator regardless of the player.

That is, &173 is provided so as to be able to swing freely using the balance pin planted in the balance pin 72 as a fulcrum, which is balanced on the shelf board 71, and the capstan button 74 erected at the rear end of this key 73 is used as a fulcrum. Wipen 76 of Action 75 via
It is a configuration that pushes up. A bush-type solenoid 79 is disposed below @73 on the shelf board 71 closer to the string 78 than the balance rail 72. Further, a key sensor 81 for detecting the vertical position of the key 73 is fixedly installed closer to the front rail 80 than the balance rail 72. Furthermore, this solenoid 79 is configured to be driven and controlled by a controller 82.

Therefore, in this player piano 70, when playing back a performance, the tip of the plunger +79A of the bush-type solenoid 79 pushes up the vicinity of the lower part of the Leipentz 6 of the key 73 to drive the key 73.

However, such a conventional player piano 70 has the following problems.

In other words, ■ the plunger 79A slides and the tip touches the key 73;
Noise is generated when the plunger 79A comes into contact with the back surface of the plunger 79A, that is, during the final movement stroke of the plunger 79A. (2) Abrasion, lateral scratches, etc. occur due to (2) above, resulting in decreased reliability. ■Key 73
Since the vicinity of the bottom of the Leipentz 6 is pushed up, the point of application of the force is different from when a pianist plays, and faithful reproduction is not necessarily possible. (2) In the so-called impact drive method, in which the plunger 79A contacts the back surface of the key 73, it is difficult to reproduce delicate playing techniques by a pianist (for example, half keys are impossible due to impact drive). (2) Impact drive (energy transmission through contact) is disadvantageous when performing feedback control (configuring a servo system to control the operation of the key 73). There are limits to improving control accuracy.

■Since the back of the key 73 is pushed up between the middle of the reed and the back of the reed, it is necessary to place a keyboard holding member in the middle of the reed (on the top surface of the balance rail) to prevent the key 73 from lifting up when the key 73 is driven. there were. However, if the position of the presser member is not properly adjusted, the key 73 may not swing properly, resulting in poor sound production.

Therefore, as an improved technique, a non-contact drive type key drive device was also considered, in which an electromagnetic coil and a lower yoke are arranged on a shelf board, and an upper yoke is fixed to the back surface of the key facing the lower yoke.

<Problems to be Solved by the Invention> However, even with the keys of automatic keyboard instruments as such improved technology, the following problems have arisen in mounting the actuator of the key drive device on the piano.

That is, the actuator mounting space varies depending on the model of the piano, as shown by (θ, 9) in FIG. 8, and the space in the height direction poses a particular problem in mounting. Since the space between the key 73 and the shelf board 71 is not very wide, in order to mount the actuator,
Lower the height of the wave during the reed, raise the keyboard,
■We had to make modifications to the piano, such as cutting off the tie plate 83.

In this case, all of the above-mentioned items (1) to (2) are difficult to modify, and the content of the work is different for many models, making it complicated.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a key for a non-contact driven automatic keyboard instrument that improves the ease of mounting the actuator, such as standardizing the mounting for each model.

Means for Solving the Problems The present invention provides a coil and a lower yoke that are disposed between a reed on a shelf board and a wave emitter and generate a magnetic force in at least the same direction as the swinging direction of the key; an upper yoke disposed on the key to face the lower yoke, the key of an automatic keyboard instrument used in an automatic keyboard instrument that drives the key according to the electric power supplied to the coil. This is a key for an automatic keyboard instrument in which a notch is formed at the upper yoke mounting position of the key, and the upper yoke is embedded and fixed in the notch.

<Function> In the key for the automatic keyboard instrument according to the present invention, the cutout portion facilitates positioning of the upper yoke, improving the ease of mounting.

Furthermore, when the actuator is mounted below the key, space is substantially increased, which can be used as space for the coil, reducing heat loss in the coil.

In addition, the size of the key notch can compensate for all differences in the space below the keyboard depending on the piano model, making it possible to install actuators with sufficient performance in all piano models. .

Since the key is not directly hit, and force is applied between the reed and the wave, no noise is generated, reliability and durability are improved, and a keyboard holding member is not required.

By changing the amount of electricity applied to the coil on the shelf, the strength of the force acting on the key can be changed, allowing for delicate control.

<Examples> Examples of the present invention will be described below with reference to the drawings.

FIGS. 1A and 1B and FIG. 3 are diagrams showing keys of an automatic keyboard instrument according to an embodiment of the present invention.

In FIGS. 1A and 1B, 11 is a key used in an automatic keyboard instrument, and this key 11 is driven by an actuator 12. In FIG.

The actuator 12 includes a lower yoke 14 fixed on the shelf board 13, an upper yoke 15 fixed on the back surface of the key 11, and a coil 16 supported by the lower yoke 14.

That is, this actuator 12 is disposed between the reed and the wave on the shelf board 13, and drives the key 11 in accordance with the electric power supplied to the coil 16.

Therefore, the coil 16 and the lower yoke 14 generate magnetic force in the same direction as the swinging direction of the key 11, and the upper yoke 15 is located on the back side of the key 11 so as to face the lower yoke 14, and is located at a predetermined mounting position. is fixed.

Here, there is a notch 17 at the upper yoke mounting position of the key 11.
is formed, and the upper yoke 15 is embedded and fixed in this notch 17.

Specifically, at a predetermined position on the back surface of the key 11, a concave cutout 17 with a trapezoidal cross section and a predetermined depth is formed so as to open downward, and a predetermined cutout is formed on the bottom of the concave cutout 17. An upper yoke 15 made of a thick metal plate is fixed with screws. The shape of the notch 17 in this case is formed to correspond to the shape of the lower yoke 14. Incidentally, the upper yoke 15 may be fixed using an adhesive other than wood screws.

When 'a11, which is used in natural musical instruments, is used as a key for this player piano, a cutter 21 is used to cut out the key, as shown in FIG. This notch processing will be even easier if all the keys are simultaneously processed as through-groove processing before the keyboard cutting step.

In the figure, the shaded area indicates a portion where the notch 17 is formed.

FIG. 3 shows a second embodiment of the invention.

In this embodiment, the cutout recess 31 is processed so that its vertical cross section is semicircular, and the upper yoke 32 is also curved and fixed in a semicircular shape corresponding to this. Further, the lower yoke 33 is also curved and formed opposite to the upper yoke 32.

Other configurations and operations remain the same as those of the first embodiment.

Further, FIG. 4 shows a third embodiment of the present invention, in which the notch 41 according to this embodiment is a trapezoidal recess, and both the upper yoke 42 and the lower yoke 43 have a shape corresponding to this trapezoid. It is formed.

Other configurations and operations are the same as those of the first embodiment.

FIG. 5 shows a fourth embodiment of the invention.

As shown in this figure, the notch 51 on the back surface of the key 50 is formed in a sawtooth shape, and the upper yoke 52 and
They each form a lower yoke 53. 54 is a coil. The area of the yoke is increased, and the heat dissipation of the coil is improved.

The other configurations and operations are the same as those of the first embodiment.

FIG. 6 is a diagram showing a fifth embodiment.

According to this embodiment, a part of the upper yoke 62 fixed to the notch 61 is extended and curved and protruded downward from the back surface of the key 60.

In other words, the upper yoke 62 is made elastic by the protrusion 62A. This gives @60 flexibility.

The other configurations and operations are the same as those of the first embodiment.

<Effects of the Invention> As explained above, according to the present invention, it is possible to lower the shelf board, raise the height of the wave radiation in the liquid and raise the key, or cut the tie plate in the liquid. There is no need to make major modifications or design changes to the main body of the piano. Furthermore, positioning of the upper yoke is easy. In this way, the ease of mounting the actuator is improved.

Furthermore, since the weight of the key is reduced by the amount of the notch, the influence of the additional weight of the upper yoke is somewhat reduced.

Therefore, there is no adverse effect on key touch.

This also makes it easier to save space for a heat diffusion device such as a heat vibrator. This improves the ease of mounting and frees up space for actuator heat dissipation.In addition, when mounting the actuator below the keyboard, the space increases substantially, which can be used as space for the coil. heat loss is reduced. The amount of heat generated by the coil can also be reduced.

In addition, the difference in the volume of the space under the keyboard depending on the piano model can be compensated for by the size of the notch in this key part, and for the purpose of improving mounting efficiency, an actuator with sufficient capacity can be mounted on all piano models. becomes possible.

In addition, since the mounting position of the drive unit has the same dimensions worldwide (in the width direction of #), it can be applied to a wider range of applications and has greater versatility.

In addition, it is not a drive method based on contact (impact method),
Since the position and movement of the key can be constantly controlled according to the applied voltage, controllability is extremely good when performing feedback control.

In addition, since the key is not hit directly, and the force is applied between the liquid and the wave, it does not generate noise, and there are no mechanical contact parts, improving reliability and durability. No parts are required.

Compared to the conventional push-up method, the thrust force (key driving force) characteristics with respect to the movement stroke are smoother.

For this reason, reproducibility is particularly improved in the low-speed drive range (during soft tone reproduction, pianissimo performance).

Furthermore, since the movable yoke and the key are integrated, the movement of the key can be controlled not only when the key is pressed, but also when the key is released.

The control range is expanded and accuracy is improved.

This makes it possible to improve the practicality of half keys and the performance of consecutive hits.

Furthermore, the magnitude of the force acting on the key can be changed simply by changing the amount of electricity applied to the coil on the shelf, allowing for delicate control.

[Brief explanation of drawings]

1(A) and 1(B) show a first embodiment of a key for an automatic keyboard instrument according to the present invention, FIG. 1(A) is a sectional view of the actuator-mounted part, Figure (B) is a sectional view taken along the line B-B in Figure 1 (A), Figure 2 is a perspective view for explaining the method of processing the notch according to the first embodiment, and Figure 3 is the present invention. FIG. 4 is a cross-sectional view showing an actuator mounting portion according to a third embodiment of the present invention; FIG. 5 is a cross-sectional view showing an actuator mounting portion according to a fourth embodiment of the present invention. 6 is a sectional view of a key according to a fifth embodiment of the present invention, FIG. 7 is a side view of a conventional player piano, and FIG. 8 is a sectional view of the mounting space of an actuator according to the present invention. It is a side view for explanation. 11 fist ・ φ ・ ・ φ ・ ・ φ12 ・
・ ・ Groan ・ ・ ・ ・ ・13 ・ ・ ・ ・
・ ・ φ ・ ・14 ・ ・ ・ ・ Meeting ・
・ ・ ・15 ・ ・ ・ ・ ・ ・ ・ ・ ・
16 fists...Conflict...Key, actuator, shelf board, lower yoke, upper yoke, coil, ・Notch.

Claims (1)

[Scope of Claims] A coil and a lower yoke that are disposed between the middle of the reed and the front of the reed on the shelf board and generate magnetic force in at least the same direction as the swinging direction of the key, and a lower yoke that faces the lower yoke. an upper yoke disposed on the key; and a key for an automatic keyboard instrument used in an automatic keyboard instrument that drives the key according to electric power supplied to the coil, the key comprising: an upper yoke disposed on the key; A key for an automatic keyboard instrument, characterized in that a notch is formed at the upper yoke mounting position, and the upper yoke is buried and fixed in the notch.