JP2638263B2 - Keyboard device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a keyboard device for a musical instrument.

2. Description of the Related Art It is desirable from the viewpoint of a touch at the time of performance that a keyboard of a musical instrument is relatively heavy at the time of initial key depression and becomes light when depressed.

The keyboard of an electronic musical instrument has a simple structure, and usually gives a return force to the key by a spring or the like. Normally, the force exerted by the spring increases in proportion to the displacement. That is, if the key is pressed down against the force of the spring, the reaction force generated by the spring increases as the key is pressed down.

Japanese Patent Publication No. 64-10076 proposes a keyboard in which the reaction force does not change much with respect to a key pressing operation by utilizing the buckling of a leaf spring, and the reaction force decreases when the displacement exceeds a certain range. .

According to such a configuration, with the key pressing operation,
A keyboard with little or no reaction force is obtained, but it is difficult to adjust because only a limited range of the characteristics of the leaf spring is used, and the key touches obtained are of a limited type .

[Problems to be Solved by the Invention] According to the conventional technology, it has been difficult to obtain a keyboard device in which the reaction force is reduced as the key is pushed and the characteristics of which can be adjusted to desired characteristics.

An object of the present invention is to provide a keyboard device that can easily achieve a desired touch feeling with a simple configuration.

Means for Solving the Problems A keyboard device of the present invention is coupled to a key that is depressed in accordance with a performance operation, a support base, and the key and the support base, and one end is rotationally engaged, An arm slidably engaged at the other end; and key return means coupled between the arm and the support base for exerting a force for returning the key to a predetermined position.

Here, the sliding engagement includes an engagement that is active on an object via a sliding member or a rolling member.

[Operation] By disposing an arm between the key and the support base, one end of which is rotatably connected and the other end of which is slidably connected, the pressing action of the key is changed to the rotational movement of the arm. You. Key return means is provided between the arm and the support base, and when a return force is applied to the arm, the return force is transmitted from the arm to the key, but by interposing the movement of the arm,
The return force can be set to decrease as the key is depressed.

By adjusting the relationship between the arm and the key return means,
The touch feeling of the key can be adjusted to a desired one.

Embodiment FIGS. 1A and 1B show a keyboard device according to an embodiment of the present invention.

FIG. 1A shows a state in which the key is in an open state and at the highest position. FIG. 1B shows a state in which the key is depressed. The key 1 of the keyboard performs a circular motion with the pivot 3 as a fulcrum. The player operates the key by pressing down the left end of the key with a finger. A rotation bearing 5 is provided on the lower surface of the key 1, and an arm 7 is rotatably connected thereto. The other end of the arm 7 is supported by a rolling
Slidingly coupled to the guide surface 13 of This rolling roller 9
And a spring 17 on the support base 11, a spring 17 is connected, and exerts a force to pull the rolling roller 9 rightward in the figure.

A guide bar 21 is fixed to the support base 11, and the guide bar 21 is provided with a stopper 23. A sliding member 25 is provided at the left end of the key 1 and is slidingly engaged with the guide rod 21. When the sliding member 25 contacts the stopper 23, the key 1
The exercise stops and the position of the key when released is determined. When the key 1 is depressed, the sliding member 25 moves downward along the guide bar 21. The arm 7 rotates about the rotary bearing 5, and the rolling roller 9 is displaced leftward. This rolling roller 9
, The spring 17 is extended.

The force applied to the key from the rotating arm by the returning force of the extended spring will be analyzed below.

FIG. 2 shows a simplified model for analysis. Although the rotary bearing 5 actually performs a circular motion, it can be regarded as a linear motion in the actual rotation range of the key. This vertical direction is defined as the x direction.
The direction orthogonal to the x direction and going leftward is defined as the y direction. When the rotary bearing 5 is displaced downward, the displacement amount is x
And The arm 7 has a length r, and its x component is x ₀ , y
Let the component be y ₀ . The spring has a length of P ₀ to the right than the x-axis, and brought into a variable length p displaced to adjust the force of the spring.

And it depresses the key, the rotary bearing 5 and x displaced downward together with the arm 7 upper rolling roller 9 is displaced from y ₀ to y to the left. At this time, since the length of the arm 7 is r, (x ₀ −x) ² + y ² = r ² (1) The left end of the spring is displaced from y ₀ to y. It is also assumed that the right end of the spring is displaced by p. Due to these displacements, a force of Fy = k (y−y ₀ + p) (2) is generated. Here, k is a spring constant of the spring, and p is an initial displacement of the spring stopper 15 for applying a bias force. Under the condition that no frictional force acts, the rotational moment of the arm 7 around the rotary bearing 5 becomes rFx Sinα−rFy Cosα, where Fx is the drag received by the rolling roller 9. here,
α is an angle between the arm r and the x-axis. Since the arm is in a balanced state, rFx Sinα−rFy Cosα = 0 Fx tanα = Fy ∴Fy / Fx = tanα = y / (x ₀ + x). ₀₋ x) dx + 2ydy = 0 y / (x ₀ −x) = dx / dy. Therefore, Fy / Fx = y / (x ₀ −x) = dx / dy Therefore, Fx · dx = Fy · dy (3) holds. In the open state, x ₀ ² + y ₀ ² = r ² (4) holds. (3) By combining expressions in the expression (2), and Fx = (dy / dx) Fy = (dy / dx) (y-y 0 + p) k. (1) Differentiating _{equation, 2ydy = 2 (x 0 -x} ) dx dy / dx = (x 0 -x) / y = (x 0 -x) / {r 2 - (x 0 -x) 2} ^1/2 Therefore, collectively, Fx = k [(x ₀ -x) / {r ^2- (x ₀ -x) ² } ^1/2 ] · [{r ^2- (x ₀ -x) ² } ^{1 / 2} −y ₀ + p] = k [(x ₀ −x) − (x ₀ −x) (y ₀ −p) / {r ² − (x ₀ −x) ² } ^1/2 ] This force is the key reaction.

Hereinafter, various parameters are set, and the reaction force of the key is obtained by calculation and is shown in a graph.

FIG. 3 shows the reaction force F when r = 10, k = 1, x ₀ = 9 and the spring extension p given in advance in the initial state of y = y ₀ is variously changed, and the key pressing depth. 3 is a graph shown as a function of the length x. When the spring is stretched in the initial state, the rolling roller 9
Receives a rightward force from the beginning. p = 0
At this time, the reaction force Fx gradually increases until the keyboard is pressed to a depth of about 2 and the reaction force eventually saturates and then decreases. p
When = 1, the region where the reaction force increases is reduced. p =
2. As p = 3 and the value of p increases, the region where the reaction force increases further decreases. In the state of p = 3,
The reaction has almost started to decrease as soon as the key is depressed.
As described above, the characteristics can be adjusted by applying a displacement to the spring in the initial stage.

FIG. 4 shows the reaction force F when r = 10, k = 1, p = 0, and the height x ₀ is changed by changing the angle of the initial rotary bearing, and the key pressing depth. 3 is a graph shown as a function of the length x. In the curve of x ₀ = 9.6, the reaction force rises sharply at the same time as the depression, and then saturates, and then decreases from around x = 1.8. As increasing the value of x _0, the position of the peak is high, and changes to the leftward (small position of x). x ₀ = 10 corresponds to the upright state.

Thus, even by possible to adjust the value of x _0, it is possible to adjust the touch feeling of the key 1.

Returning to FIGS. 1 (A) and 1 (B), in order to diversify the above adjustment, the position of the spring stopper 15 for locking the spring 17 is made variable, and the position of the rotary bearing 5 is changed. For example, it is desirable to take measures such as making it variable within a slot. By such adjustment, the touch feeling can be improved without using any special spring.

Although the present invention has been described with reference to the embodiments, the present invention is not limited thereto. For example, the spring is not limited to a coil spring, and various springs can be used. Further, the configuration in which the spring expands when the key is pressed has been described, but the configuration may be such that the spring contracts when the key is pressed. The arm is arranged to be moved in the direction of the tip when the key is depressed, but may be arranged to be moved in the direction of the fulcrum. Further, although the pivot point of the arm is provided on the keyboard side, other configurations such as providing the pivot point on the support base side may be adopted. The spring need not be attached to the tip of the arm as long as it is connected to the arm. Further, although the configuration using one arm has been described, a configuration using two arms to be engaged and using a spring between them may be adopted. It will be apparent to those skilled in the art that various changes, improvements, combinations, and the like can be made.

[Effects of the Invention] As described above, according to the present invention, it is easy to realize a keyboard device having a desired touch feeling.

Further, it is easy to adjust the touch feeling of the keyboard device.

[Brief description of the drawings]

1 (A) and 1 (B) are side views showing two states of a keyboard device according to an embodiment of the present invention, and FIG. 2 is an embodiment shown in FIGS. 1 (A) and 1 (B). FIG. 3 is a conceptual diagram showing a model for studying the reaction force of the key in FIG. 3, FIG. 3 is a graph showing the relationship between the reaction force changed by the initial displacement of the spring and the key depression depth, and FIG. It is a graph which shows the relationship with the key depression depth of the reaction force which changes with an angle. In the drawing, 1... Key 3... Pivot point 5... Rotary bearing 7... Arm 9... Rolling roller 11. Rod 23 Stopper 25 Sliding member

Claims (1)

(57) [Claims] A key which is depressed in accordance with a performance operation; a support base; an arm which is connected between the key and the support base, one end of which is rotationally engaged and the other end of which is slidably engaged; A key return means coupled between the arm and the support base, the key return means exerting a force for returning the key to a predetermined position.