JPH087572B2 - Electronic musical instrument keyboard device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a keyboard device for an electronic musical instrument, which provides a key touch feeling similar to that of a piano.

[0002]

2. Description of the Related Art Conventionally, a keyboard device for an electronic musical instrument has a key touch feeling different from that of an acoustic piano, so that the expressive power of a performer cannot be sufficiently realized. Therefore, various keyboard devices have been implemented or proposed so as to approximate the touch feeling of a piano.

FIG. 8 is a sectional view showing an example of a conventional keyboard device of this type. As shown, the conventional keyboard device has a key 1
A leaf spring 12a is used to give a restoring force to the key 1, and a weight 15 is embedded at the tip of the key 11 to give an inertial force to the key 11, and the touch feeling of a piano is to be realized by such a configuration. In this keyboard device, when the key 11 is pressed against the biasing force of the leaf spring 12a, the actuator 1 provided on the lower surface of the key 11
At 3, the lower key switch 14 is operated, and after releasing the key pressing operation, the key 11 is returned by the restoring force of the leaf spring 12a.

In Japanese Utility Model Laid-Open No. 57-88186, an action mechanism consisting of a hammer and a weight is provided below the keyboard frame, and the action mechanism is rotated in conjunction with the key-pressing operation of the key, thereby producing a piano. It has been proposed to obtain a key touch feeling similar to.

[0005]

However, in the keyboard device as shown in FIG. 8, the touch feeling (static touch feeling) when the key 11 is slowly pressed is similar to the touch feeling of a piano. The touch feeling (dynamic touch feeling) when the key 11 is suddenly pressed was still insufficient. That is,
This dynamic touch feeling is mainly determined by the moment of inertia of the keyboard device, but it is an attempt to realize a large inertial force like that of an acoustic piano equipped with an action mechanism using only the weight of the key without the action mechanism. Then, it is necessary to increase the weight of the weight, which causes a problem in mechanical strength and space.

Further, in the above-mentioned keyboard device, since the key switch 14 is operated by the actuator 13 provided on the lower surface of the key 11, no matter what key pressing operation is performed, the key 11 is operated.
Is not pronounced unless it sinks a certain amount. That is, the keyboard device can produce sound only when the key is depressed by a certain amount. On the other hand, in the acoustic piano, even if the amount of depression of the key is small, the key produces a sounding action by applying a force sufficient for the hammer to reach the string. That is,
Acoustic piano pronunciation is not directly related to the amount of key depression. Therefore, the keyboard device as shown in FIG. 8 cannot support the above-described performance method using the sounding operation of the piano, and has a problem of poor expression.

On the other hand, Japanese Utility Model Application Laid-Open No. 57-88186 proposes a solution to the above problems by providing an action mechanism consisting of a hammer and a weight below the keyboard frame. In the keyboard device disclosed in the publication, since a hammer having a large inertia weight is braked only by the cushioning material provided on the keyboard frame at the time of hitting a key, the rebound and noise when the hammer hits the cushioning material is completely eliminated. It is difficult to suppress, and there is a problem that such a rebound causes an unpleasant touch feeling. Further, in the arrangement of the key and the hammer as described in the above publication, there is also a problem that the rotational force of the key is not smoothly transmitted to the hammer.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a keyboard device for an electronic musical instrument, which has a compact structure and can provide a key touch feeling similar to that of an acoustic piano. .

[0009]

A keyboard device for an electronic musical instrument according to the present invention is provided with a key that is vertically swingable relative to a keyboard frame, and is rotated below a key by receiving an action force when the key is pressed. In a keyboard device of an electronic musical instrument provided with a hammer that moves and returns when the pressing operation is released, a contact point between the key and the hammer during the pressing operation of the key is defined by a straight line connecting the rotation center of the key and the rotation center of the hammer. It is characterized in that it is provided on a flat surface including.

[0010]

According to the present invention, above the rotation axis of the hammer, a plane including a straight line connecting the center of rotation of the key and the center of rotation of the hammer at the point of contact between the key and the hammer when the key is pressed. By being provided above, the occurrence of slippage that causes a loss of rotational force at the contact point immediately after keystroke and causes wear of the key at the contact point is prevented, and the force of the key directly becomes the rotational force. It is transmitted to the hammer and the dynamic touch feeling close to that of an acoustic piano is effectively realized.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a keyboard device according to an embodiment of the present invention. The keyboard device of this embodiment is provided at its lower portion with a keyboard frame 21 whose front end side (right side in the figure) and rear end side (left side in the same figure) are convex upwards. The keyboard holder 2 is on the upper surface of the convex portion on the end side.
2 is attached.

The keyboard holder 22 has projections 23 and 24 projecting upward at the rear end and the front end, respectively, and the projection 23 on the rear end side is integrally formed of synthetic resin. The rear end of the key 25 is pivotally supported by a shaft such as a pin, and the projection 24 on the front end side has a hammer 26 formed of an alloy having a high specific gravity or a hard synthetic resin or the like for increasing the moment of inertia. The rear end side is also pivotally supported by a shaft such as a pin.

The key 25 has a hollowed back surface,
A projection 27 that functions as an actuator is integrally formed on the rear end side of the back surface so as to project downward.
Further, a chamber portion 28 that opens downward is formed at the front end of the key 25, and a weight 29 for giving the key 25 a required weight feeling, that is, inertial force, is formed inside the chamber portion 28. It is fixed by means such as a set screw or adhesion. By providing the weight 29 in this way,
It is possible to secure a static load amount when the key is pressed slowly, and to obtain a static touch feeling similar to that of an acoustic piano only by weight balance without using an elastic material such as a spring. Further, on the side wall of the key 25 near the chamber portion 28, a notch 30 that is recessed toward the back side of the key 25 and a protrusion 31 that protrudes rearward from the lower portion of the chamber portion 28 are provided. 30 and the protruding portion 31 are configured to abut on a stop felt 32 and a cushion 33 provided on a keyboard frame 21, which will be described later, respectively.

On the other hand, the hammer 26 is always given a habit of returning (rotating) in the clockwise direction in FIG. 1 by the rotational force due to its own weight, and is provided on the rear end side of the rotating shaft when the projection 27 comes into contact. It has a flat portion 34 that receives a force from the protrusion 27, a friction engagement portion 35 provided above the rotating shaft, and an arm portion 36 provided on the front end side of the rotating shaft. here,
The flat portion 34 is provided with an elongated hole 37 in the left-right direction (direction orthogonal to the paper surface), whereby the surface of the flat portion 34 is elastically deformed when the protrusion 27 and the flat portion 34 come into contact with each other. The force from the protrusion 27, that is, the key 25 can be absorbed. The front end of the arm 36 is inserted into the opening of the keyboard frame 21 so as to be movable. When the hammer 26 rotates, the cushion 38 and the arm 36 provided on the keyboard frame 21 at the upper limit of the rotation of the hammer 26.
The upper surface of the tip of the hammer contacts the upper surface of the arm, and the cushion 39 also provided on the keyboard frame 21 and the lower surface of the tip of the arm portion 36 contact at the lower limit of rotation, so that the impact force from the hammer 26 can be effectively absorbed. You can do it. Further, the friction engagement portion 35 is formed in an upwardly convex arcuate curved surface,
A friction member 40 made of synthetic rubber or synthetic resin is provided on the surface. When the friction engagement portion 35 abuts the abutment portion 41 on the lower surface of the key 25, the friction between the friction member 40 and the abutment portion 41 restricts the rotation of the hammer 26 in the counterclockwise direction in the figure. Absorb power.

Two switches 42 and 43 are arranged on the upper surface of the keyboard holder 22 in parallel with each other in the extending direction of the hammer 26, and the flat portion 34 of the hammer 26 is provided while the flat portion 34 reaches the lower limit position. The lower surface of the switch is configured to press both switches 42 and 43 with an arbitrary time difference. The operation of the keyboard device thus configured will be described below with reference to FIG.

First, when the key 25 is pressed to rotate clockwise in the figure, the projection 27 presses the upper surface of the flat portion 34 of the hammer 26 in contact with the projection 27. As a result, the hammer 26 rotates counterclockwise against the rotational force due to gravity, and the lower surface of the flat portion 34 first presses the switch 43, and then the switch 42, and the key 25
The musical sound corresponding to the exercise is generated electrically. By shifting the operation timings of the two switches 42 and 43 in this way, the time difference between the signals from these switches 42 and 43 is detected, and the variation amount of the musical tone, the envelope,
It is possible to control the timbre change amount and the like.

When the key 25 is further depressed and the arm portion 36 of the hammer 26 reaches near the upper limit position of rotation, on the other hand, the friction engagement portion 35 of the hammer 26 is pressed against the contact portion 41 on the inner surface of the key 25. By the frictional engagement between the friction member 40 and the contact portion 41, the counterclockwise rotation of the hammer 26 and the clockwise rotation of the key 25 are restricted, and on the other hand, the key 2
When the notch 30 of FIG. 5 is pressed against the stop felt 32, the tip of the hammer 26 is pressed against the cushion 38, thereby restricting the rotation of the key 25 and the hammer 26 in the respective directions, and the respective turning powers. Is absorbed.

The above operation will be described in more detail with reference to FIG. This drawing shows the friction engagement portion 3 of the hammer 26.
5 is in contact with the contact portion 41 of the key 25 and holds the hammer 26. By pressing the key, the notch 30 of the key 25 abuts the stop felt 32 and the hammer 26
When the frictional engagement portion 35 of the above contacts the abutment portion 41 of the key 25, the force received by the hammer 26 from the protrusion 27 is absorbed by the cushion 38, but the hammer 2 having a large inertial force.
Since 6 continues to rotate counterclockwise, the cushion 38 is compressed and further sinks, whereby the friction engagement portion 35 is pressed against the contact portion 41, and the back surface of the key 25 is moved to the right in the figure. A large frictional force F is generated toward it. Correspondingly, the contact surface between the friction engagement portion 35 and the contact portion 41 receives a reaction force N against the cushion 38 of the hammer 26, and a friction force F ′ is applied to the back surface of the key 25 toward the left side in the drawing. Occurs. The frictional force F restricts the counterclockwise rotation of the hammer 26 to cancel the force, and the frictional force F'is the hammer 26.
The counterclockwise pivoting forces of the two are counteracted and together hold the hammer 26. As shown in FIG. 3, the components of these frictional forces F and F ′ in the rotation direction of the key 25 are
The straight line C-C 'that connects the rotation axis of 4 to the contact points of the frictional engagement portion 35 and the contact portion 41 has an extremely small angle with the frictional forces F and F'. Sometimes the hammer 26 does not feel the recoil of the hammer 26, and it is possible to prevent the hammer 26 from cracking and noise, and to prevent erroneous operations such as double strikes due to the rebound operation of the hammer 26.

When the pressing force applied to the key 25 is released, the hammer 26 is rotated counterclockwise by the action of gravity, pushing up the protrusion 27 of the key 25, and the protruding portion 31.
Comes into contact with the cushion 33 and elastically receives the counterclockwise rotation of the key 25, whereby the key 25 is maintained in the initial position. Next, the contact position between the protrusion 27 of the key 25 and the flat portion 34 of the hammer 26 and the direction of the force will be described with reference to FIG.

In the figure, a straight line DD 'connecting the rotation axis D of the key 25 and the rotation axis D'of the hammer 26 is a reference line for determining the contact position, and is shown in FIG. , (B),
(C) is a line D-D 'in which the protrusion 27 and the flat portion 34 are brought into contact with _{each other} at a point P ₁ above the plane including the line D-D'.
A point P ₂ on the surface including the line and a point P ₃ on the surface including the straight line DD ′ are shown. In each of these cases, the force received by the hammer 26 that engages with the key 25 at the moment when the key is hit will be described with reference to FIG. In the case of abutting at points P ₁ and P ₃ , as shown in FIG. 5 (A), when the forces F ₁ and F ₃ received at abutting points P ₁ and P ₃ are decomposed into their respective component forces, axis D The component forces T ₁ and T ₃ in the'direction and component forces N ₁ and N ₃ in the direction orthogonal to the axis D'become component forces T ₁ and T _3.
Is a load on the shaft D ′, and moreover, due to these component forces T ₁ and T ₃ , slip occurs between the protrusion 27 and the hammer 26 at the contact point between them, which causes a loss of rotational force and causes wear of the protrusion 27. Becomes On the other hand, when abutting at a point P ₂ on the surface including the straight line DD ′, FIG.
As shown in (B), the force F ₂ received at the contact point P ₂ becomes the rotational force as it is without causing any loss of the rotational force immediately after keying, that is, the component force in the rotational direction.
It is transmitted to 6. The position of the contact point varies depending on the position of the rotating shaft, but in order to improve the ratio of the turning angle of the hammer 26 to the turning angle of the key 25 and increase the moment of inertia, the position is limited by design. It is preferable to select a position close to the center of rotation of the hammer 26.

The present invention is not limited to the above embodiment, but various modifications and changes can be made. For example, in the above embodiment, the hole 37 is provided in order to reduce the impact force applied to the finger at the time of keystroke. However, as the impact force mitigating means, other means are shown in FIGS. 6 (A) and 6 (B). As described above, the hole 37 may be further filled with an elastic material 44 such as synthetic rubber (see FIG. 6A), and a recess 45 is formed in the flat portion 34, and the elastic material is provided in the recess 45. 44
May be attached (see FIG. 6 (B)).

The hammer 26 may be installed in the opposite direction to that of the above embodiment, as shown in FIG. With such a configuration, the protrusion 2
7, the switches 42 and 43, and the cushions 38 and 39 need to be arranged corresponding to the position of the hammer 26.

[0023]

The present invention is configured as described above,
Since the contact point between the key and the hammer during the pressing operation of the key is provided on the plane including the straight line connecting the center of rotation of the key and the center of rotation of the hammer, the hammer can efficiently rotate the key. The dynamic touch feeling similar to that of an acoustic piano can be effectively realized by being transmitted to.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a keyboard device according to an embodiment of the present invention.

FIG. 2 is an operation explanatory view of a hammer in the keyboard device according to the embodiment of the present invention.

FIG. 3 is an explanatory view for explaining a state when a key and a hammer are in contact with each other in the keyboard device of one embodiment of the present invention.

FIG. 4 is an explanatory view for explaining a difference in effect depending on an abutting position between a key protrusion and a hammer flat portion in one embodiment of the present invention.

FIG. 5 is an explanatory view showing a force acting on a flat portion of a hammer from a key protrusion according to an embodiment of the present invention.

FIG. 6 is a view showing a modified example of the impact force alleviating means in one embodiment of the present invention.

FIG. 7 is a sectional view of a keyboard device according to another embodiment of the present invention.

FIG. 8 is a sectional view of a conventional keyboard device.

[Explanation of symbols]

 21 keyboard frame 22 keyboard holder 23, 24 protrusion 25 key 26 hammer 27 protrusion 29 weight 34 flat portion

Claims (1)

[Claims] 1. An electronic musical instrument, wherein a key is provided so as to be swingable up and down with respect to a keyboard frame, and a hammer is provided below the key, the hammer being actuated when the key is pressed to rotate and to return when the press is released. In the keyboard device, the contact point between the key and the hammer at the time of pressing the key is provided on a plane including a straight line connecting the rotation center of the key and the rotation center of the hammer. Electronic musical instrument keyboard device.