JPS6333239Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a keyboard device that allows an electronic musical instrument such as an electronic organ to have a key touch feeling similar to that of a piano.

[Conventional technology]

Conventionally, keyboard devices for electronic musical instruments such as electronic organs have had a significantly different feel when hitting the keys, that is, the feeling of touching the keys, than the feeling of touching the keys of a piano, which is a natural musical instrument, so people have practiced playing on electronic organs. In some cases, it was difficult to get used to the piano and make a smooth transition to the piano. This is because the keys of electronic musical instruments are configured to simply be pressed against the force of a spring, so the jack (or hammer shank) is pushed up at the beginning of the key press, similar to the keyboard device on a piano. This is because the reaction force applied to the fingertips gradually increases as the key is pushed in, contrary to the piano action in which the reaction force applied to the fingertips decreases rapidly by escaping from the butt (hammer shank). It lacked the touch response function that conveys the player's emotions, making it difficult to play.

Therefore, as a method to solve this problem, for example, as shown in Japanese Utility Model Application Publication No. 55-84673,
A swingable lever is arranged below the key so as to correspond to each key, the front end of the lever is brought into contact with the lower surface of the key, and the rear end is provided with a biasing force that resists the pressing force of the key. A keyboard instrument has been proposed that is provided with a weight that gives the lever a weight.

[Problem that the invention attempts to solve]

However, even in such conventional keyboard devices, since the angle of inclination of the lever in the initial position is small, the rotational moment generated from the lever's inertial resistance force and other biasing forces is applied from the start of key depression, and the piano The drawback was that you could not get the feeling of escape when pressing the key. Therefore, for example, it may be possible to increase the inclination angle of the lever and change the pressure angle of the key against the lever, but in that case, the rear end of the lever would be lowered and the height of the device itself would increase, making it more compact. There was a problem.

This invention aims to solve the above-mentioned problems and provide a keyboard device for an electronic musical instrument that is compact and provides a touch feel similar to that of a piano.

[Means for solving problems]

In order to achieve the above object, this invention has a key 1 which is disposed on a keyboard frame 2, extends substantially horizontally, and has an actuator section 13 on the lower surface, and which is vertically swingable.
Then, the key 1 is moved so that it comes into contact with the actuator section 13 at a position a predetermined distance away from the center of rotation B.
In a keyboard device for an electronic musical instrument, the hammer arm 12 is arranged to be vertically swingable below the key 1 and extends in substantially the same direction as the key 1. The hammer arm 12 resists the pressing force of the key 1. The contact portion between the hammer arm 12 and the actuator portion 13 has a biasing force such as
2, and this contact surface 12A is provided to be inclined with respect to the extending direction of the hammer arm 12, and the inclination angle r ₂ in its initial state is the same as the contact surface 12A. A line connecting the contact point C with the contactor 16 and the rotation center B
This is set to be larger than the inclination angle _r1 of B'-B'.

[Effect]

With this invention, the pressure angle at the contact area between the key and the hammer arm can be independently changed and set without changing the inclination angle of the hammer arm itself, increasing the degree of freedom in setting the change pattern of the touch response. That is, at the beginning of a key press, inertial resistance and the like associated with the start of rotation of the key etc. are transmitted to the finger as a reaction force, but this begins to decrease as the key accelerates. If the contact surface between the key and the hammer arm is tilted at a predetermined angle to increase the pressure angle, and the change pattern is appropriately modified, the component force between the contact surface and the contact during the key press can be increased. The reaction force is reduced due to the relationship and slippage, and the operating force can be reduced. If the pressure angle decreases in the middle of the key depression, the reaction force from the hammer arm will be sufficiently transmitted to the key side. Subsequently, when the hammer arm is sufficiently accelerated, this reaction force decreases, but eventually the key is stopped by the lower limit stopper, and a large reaction force is transmitted to the finger.

〔Example〕

This invention will be described in detail below based on embodiments shown in the drawings.

FIG. 1 is a longitudinal sectional view showing an embodiment of the keyboard device according to this invention. The key 1, which extends substantially horizontally above the keyboard frame 2 and is arranged to be able to swing up and down, is integrally formed of synthetic resin, and its lower surface is hollowed out as shown in the figure, and the rear end is hollowed out. It is fixed onto a metal key frame 3 with a set screw 4. The key frame 3 has a substantially trapezoidal notch 5 provided on the lower surface of the rear end, and this notch 5 engages with the upper end of the fulcrum plate 6 provided on the keyboard frame 2, thereby allowing the notch to be opened. It is supported so as to be able to swing up and down using the notch 5 as a rotational fulcrum, and is constantly given a return habit in a counterclockwise direction in the drawing by a tension spring 7.

A weight 8 is attached to a set screw 9 in the hollowed out portion on the bottom of the tip of the key 1 to give the key 1 an appropriate sense of weight.
Alternatively, an upper limit stopper 11 for driving the upward rotation of the key 1 and a hammer arm 12, which will be described later, are attached to the lower end surface of the protrusion 10, which is fixed by adhesive or the like and is vertically provided on the lower surface, and which is driven when the key is pressed. An actuator 13 is fixed by a set screw. The upper limit stopper 11 extends below the frame 2 through a through hole 14 formed in the keyboard frame 2, and has a lower end bent approximately horizontally, and is bonded to the lower surface of the front end of the keyboard frame 2 or as described below. By being pressed from below by the force of the spring 7 to the cross 15a formed integrally with the cross 15b for the lower limit stopper, the key 1 is locked in the substantially horizontal initial position shown by the solid line. . Similarly, the actuator 13 extends downward and faces the through hole 14, and has a contact element (pressure element) made of metal or synthetic resin coated with graphite on the lower surface of its obliquely bent lower end. ) 16 is fixed. Note that the contactor referred to herein is made of a curved surface with a small radius of curvature, and transmits force while locally contacting the contact surface. Therefore, it is sufficient that a contact having a predetermined shape is provided at a predetermined position and is dynamically integrated with the key.

The hammer arm 12 is made of metal or hard synthetic resin, and is disposed on the lower surface of the keyboard frame 2 so as to be able to swing up and down, and extends in substantially the same direction as the key 1. It is rotatably supported via a horizontal shaft 18 by a bracket 17 attached to the lower surface of the center thereof. The front end of this hammer arm 12 is an actuator 13
It is bent upward so as to face the presser (contact element) 16 to form a contact part (contact surface) 12A,
A cushioning material 19 made of urethane rubber, cloth, or the like is adhered to the upper surface to constitute a contact surface (also a sliding surface) having shock-absorbing properties. By bending the contact portion 12A, the contact surface is inclined at a predetermined angle with respect to the extending direction of the hammer arm, so that the pressure angle is increased by an appropriate amount.

On the other hand, a weight 20 of an appropriate weight is fixed to the rear end surface of the hammer arm 12 extending rearward by means such as adhesive, screwing, or integral molding. For this reason, the hammer arm 12 is given a counterclockwise rotational habit by the weight 20, and this weight 20 is placed on the upper surface of the stopper 21 vertically installed on the lower surface of the key frame 2 via the felt 30. As a result, the cushioning material 19 is locked in the initial position tilted at a predetermined angle as shown by the solid line, and the cushioning material 19 is in contact with the presser 16 in this state. In this case, the distance from the pivot point of the hammer arm 12, that is, the shaft 18, to the weight 20, and the distance from the shaft 18 to the key 1
The distances to the key press operation section 1A are set to be approximately equal. In addition, the force acting on the key 1 of the tension spring 7 is due to the weight 20 on the hammer arm 12.
Since the actuator 13 is pushed up by the rotational force of the key 1 and the key 1 is rotated back, it is sufficient to support the key 1 to the extent that it does not bounce after returning. Note that this cushioning material 19 and the presser 1
Since other frictional conditions of the cushioning properties will also change depending on the combination of the materials listed in item 6, it is best to consider both factors when deciding on the material.

The lower limit stopper cross 15b is adhered to the upper surface of the front end of the keyboard frame 2, and a key guide 22 for regulating the movement of the key 1 in the left and right direction is provided upright. Further, a key switch 23 is fixed to the lower surface of the rear end of the keyboard frame 2, and has a bullet contact 23a which is controlled to open and close by a protrusion 24 protruding from the rear end of the hammer arm 12. A felt 25 is fixed in correspondence with 20.

Next, the operation of the keyboard device configured as described above will be explained.

In the state shown by the solid line in the figure, that is, in the initial state, when the key press operation part 1A of the key 1 is pushed downward with a finger, the key 1 rotates clockwise using the notch 5 of the key frame 3 as a rotation fulcrum. Accordingly, the actuator 13 descends together with the key 1, and the pusher 16 pushes up the cushioning material 19 of the hammer arm 12.
At this time, the resultant force of the static and dynamic frictional forces between the pusher 16 and the buffer material 19 and the force in the normal direction of the contact surface at the contact point (vertical force) acts on the key as a reaction force to the key press operation. At the same time, the weight 20 of the hammer arm 12 is raised from a stationary state by the rotation of the hammer arm 12 as the actuator 13 descends, but the force acting on the hammer arm 12 at this time is the source of the above-mentioned reaction force. It's summery. At the initial stage of pressing the key, the inertial resistance force accompanying the acceleration of the key is first transmitted to the finger as a reaction force, and further, when the key starts to move, the actuator 13 moves the contact portion 12 of the hammer arm 12.
Since it is in contact with A, this weight 20 also acts as a reaction force against the key press operation. As a result, the reaction force applied to the fingertip at the start of key depression temporarily increases. When the key 1 and the hammer arm 12 are accelerated to a certain extent, the inertial resistance force starts to decrease because there is a limit to the finger acceleration operation. At this time, the surface of the contact portion (contact surface) between the key 1 and the hammer arm 12 is
Since the pressure angle is increased by an appropriate amount by tilting at a predetermined angle, in addition to adjusting the component force relationship, the presser 16
A slip occurs between the hammer arm 12 and the cushioning material 19, and the component of the reaction force from the hammer arm 12 to the key 1 in the rotational direction is reduced. As the rotation of the hammer arm 12 progresses and the pressure angle decreases, this decreasing state weakens.
The reaction force transmitted to the finger increases, and the key 1 becomes able to sufficiently accelerate the hammer arm 12. If the acceleration at this time is sufficient, the reaction force transmitted to the finger will begin to decrease again, but eventually the key will collide with the lower limit stopper and stop. In this way, it is possible to obtain a feeling of escape when touching keys that is similar to that of a piano.

FIG. 2 is a diagram for explaining the force acting on the contact portion 12A, where Q is the dead weight of the hammer arm 12, and the weight 2
0 etc., N is the normal force received from the presser 16 at the contact point C, M is the force from the rotation center B18 of the hammer arm 12 acting on the contact portion 12A, μN is the force applied to the presser at the contact C 16, and it is assumed that these are in a balanced state. Now let R be the vector sum of N and μN, and let P be the component force of R in the direction perpendicular to the radius from the rotation center A of key 1, that is, in the mm direction.
It can be seen that equations (1), (2), and (3) hold true.

P=Rcos(θ−ρ)…(1) Q=Rcos(Φ−ρ)…(2) μ=tanρ…(3) However, ρ is the friction angle (friction coefficient μ), and Φ is the pressure angle (ss and nn intersection angle), tt... tangent (to the contour curve of the presser 16), nn... normal line, ss... contact point C
A tangent to the motion curve of the contact portion 12A at,
mm...Tangential line to the motion curve of the presser 16 at contact point C, ll...Extending direction of the hammer arm 12, θ...Angle between radius vector and tangent line tt, θ ₀ ...
The intersection angle between ss and mm, B'-B'...The line connecting the center of rotation B of the hammer arm 12 in the initial state and the contact point C, _r1 is the inclination of the line B'-B' with the horizontal line in the initial state. The angle, r ₂ is the contact surface 12A in the initial state
The angle of inclination is set to be greater than r ₁ .

When R and ρ are eliminated from equations (1), (2), and (3) above, P=Q・cos(θ−ρ)/cos(Φ−ρ) =Q・cosθ+μsinθ/cosΦ+μsinΦ…(4) However, θ=Φ+θ ₀ (θ ₀ is a constant).

As is clear from equation (4), the key operating force P is determined by the inclination angle of the contact portion 12A, that is, the pressure angles Φ and θ, and is not related to the inclination angle α of the hammer arm 12 itself. , the angle α can be set freely and sufficiently smaller than θ, and the inclination angle β of the contact surface of the contact portion 12A with respect to the extending direction of the hammer arm is set so that the desired pressure angle Φ is obtained.

On the other hand, if θ is made smaller and equal to the intersection angle θ ₀ between SS and mm, Φ=0 and N=−Q. In this way, the dynamic friction (sliding amount) between the presser 16 and the contact portion 12A during a key press operation is reduced.
In addition, suppose that the rotation center A on the key side is set so that θ ₀ ≒ 0.
If the hammer arm side rotation center B is selected, P≈-Q, and no slipping occurs between the presser 16 and the contact portion 12A. In such a case, as described above, the rotational moment generated from the inertia of the hammer arm 12 acts on the player from the start of the key-pressing operation, making it difficult to touch the piano key with a feeling of escape. In addition, by appropriately selecting the materials of the cushioning material 19 and the presser 16, it is possible to change from static to dynamic (sliding).
It is possible to clarify the change in frictional force that corresponds to the change in , and further strengthen the feeling of escape.

Furthermore, if the inclination angle α of the hammer arm 12 is increased to be equal to the inclination angle θ of the contact portion 12A, and β=0 instead, a key touch feeling similar to that of a piano can be obtained, but the arm 12 Since the rear end is lowered, the height dimension of the electronic musical instrument increases, which is unsuitable. In addition, in formula (4), the slope is on the key 1 side, and the pusher 1 is on the side of the key 1.
This also holds true when the relationship between 6 and the buffer material 19 is reversed.

FIG. 3 is a sectional view of a main part showing another embodiment of this invention. In this embodiment, the hammer arm 12 and the weight 20 are connected by soft plastic, soft rubber, etc. affixed to the upper and lower surfaces of the rear end of the hammer arm 12.
This is measured through cushioning materials 26 and 27 made of felt or the like, and the other configurations are the same as those of the above embodiment. This configuration has the advantage that the touch feeling felt by the fingertips when typing a key can be made softer.

In addition, in the above embodiment, the hammer arm 1
2 is configured to drive the key switch 23, but this invention is not limited to this; the key switch 23 is provided on the upper surface (or lower surface) of the central part of the keyboard frame 2, and an actuator for the key switch is provided on the key 1, Of course, this actuator may be used for direct driving. In addition, the key switch 23 can be controlled by the hammer arm 1 depending on the strength of the key operation force.
If the switch is used as a switch to detect the speed of the key 1 and hammer arm 12, and the time taken for the bullet contact 23a to leave the lower contact 23b and contact the upper contact 23c is converted into an electrical signal, the rotation of the key 1 or the hammer arm 12 can be detected. Pronunciation can be controlled based on speed, and it is possible to obtain musical expressiveness similar to that of a piano.

Furthermore, weights 8, 20, hammer arm 12,
By appropriately selecting the materials, shapes, etc. of the presser 16 and the cushioning material 19, a desired key touch feeling can be obtained.

[Effects of the invention] As explained above, the keyboard device for an electronic musical instrument according to this invention has a hammer arm with a weight attached below the key so as to be able to swing vertically, and a contact area between the hammer arm and the key. is a combination of a contact and a contact surface, and by inclining the contact surface with respect to the extending direction of the arm, the inclination angle of the contact surface in the initial state can be changed between the contact point of the contact surface and the contact and the hammer arm. Since the inclination angle is set to be larger than the inclination angle of the line connecting the center of rotation, it is possible to independently change the pressure angle between the key and the hammer arm without changing the inclination angle of the hammer arm itself. It is possible to set a reaction force change pattern close to a desired one, and it is possible to obtain a key touch feeling similar to that of a piano. Further, since the structure can be simplified and the inclination angle of the hammer arm can be made small, the degree of freedom in design can be increased and the height dimension of the device can be set small, making it possible to make the device compact.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing one embodiment of the keyboard device for an electronic musical instrument according to this invention, Fig. 2 is a diagram for explaining the effects of this invention, and Fig. 3 is a diagram showing another embodiment of this invention. FIG. DESCRIPTION OF SYMBOLS 1... Key, 2... Keyboard frame, 3... Key frame, 12... Hammer arm, 12A... Contact part (contact surface), 13... Actuator, 16...
...Contact part (presser), 18...Shaft, 19...Buffer material, 20...Weight, 23...Key switch.

Claims (1)

[Scope of utility model registration request] A key 1 is arranged on a keyboard frame 2, extends substantially horizontally, and has an actuator section 13 on its lower surface, and is swingable up and down. In a keyboard device for an electronic musical instrument, the hammer arm 12 is provided below the key 1 so as to be vertically swingable and extends in substantially the same direction as the key 1. The contact portion between the hammer arm 12 and the actuator portion 13 has a biasing force that resists pressure, and the contact portion between the hammer arm 12 and the actuator portion 13 is formed by a contact 16 provided on the actuator portion 13 and a contact surface 12A provided on the hammer arm 12. The contact surface 12A is provided at an angle with respect to the extending direction of the hammer arm 12,
The inclination angle r ₂ in the initial state is between the contact point C between the contact surface 12A and the contactor 16 and the rotation center B.
A keyboard device for an electronic musical instrument, characterized in that the inclination angle r of a line B'-B' connecting the lines B'-B' is set to be larger than ₁ .