JPH08314438A - Keyboard device - Google Patents

Abstract

PURPOSE: To obtain a compact keyboard device with which the key touch feel extremely resembling the key touch feel of an acoustic piano is obtainable. CONSTITUTION: A jack 17 is freely oscillatably and pivotally supported at a key 5 disposed at a keyboard frame 1 freely oscillatably around an oscillation fulcrum P as a center and a hammer 8 which is a mass body is oscillated by the force transmitted via this jack 17 at the time of key touch. A regulating button 20 in common use as a key guide which guides the oscillation direction of the key 5 at the time of key operation and oscillates in a direction of disengaging from the hammer 8 by coming into contact with the jack 17 during the course of the operation is erected on the keyboard frame 1 near the front end of the key 5. Further, the oscillation fulcrum P of the key 5, the shaft 18 of the jack 17, and the contact part Q of the jack 17 with the regulating button 20 in common use as the key guide are so disposed as to line up on nearly one straight line.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a keyboard device suitable for a keyboard electronic musical instrument such as an electronic piano or a practice device for a keyboard musical instrument such as a piano.

[0002]

2. Description of the Related Art A keyboard device for an electronic keyboard musical instrument such as an electronic organ has a large number of white keys and black keys arranged in a row around a fulcrum portion with respect to a support member such as a keyboard frame and the like. The key driving section is configured to turn on a key switch to generate a musical sound. Furthermore, it has become possible to generate musical tones similar to those of an acoustic piano in an electronic keyboard instrument, and accordingly various electronic pianos have been developed that can provide a key touch feeling similar to that of an acoustic piano in a keyboard device. ing.

Examples of keyboard devices for such an electronic piano include, for example, Japanese Utility Model Publication No. 4-101595 and Japanese Utility Model Publication No.
-120999, Japanese Utility Model Laid-Open No. 4-114096, and Japanese Patent Laid-Open No. 4-303891. In each of these, a hammer (mass body equivalent to the hammer of an acoustic piano) that swings in synchronization with the swing of the key is provided, and due to its inertial force, a strong resistance feeling when pressing the key and a weak key pressing This makes it possible to obtain a difference in the dynamic touch feeling when a key is pressed hard.

Further, a jack pivotally supported by the key is interposed between each key and the hammer, and when the key is pressed, the hammer swings by the jack, and at the end of the operation, the jack is held against the key. By rotating the lever to release the engagement with the hammer, the resistance to the player's fingers is sharply reduced to give a static or dynamic let-off feeling (escape feeling), and the key touch of the acoustic piano is performed. I try to get a touch feeling close to the feeling.

In a keyboard apparatus having such a hammer, the ratio of the stroke of the center of gravity (mass point) of the hammer to the stroke of the tip (end on the front side) of the key during key operation is commonly called the expansion ratio (rate). With a grand piano, this is about 1: 5, but this has a large absolute stroke of the hammer, and is not a size that can be mounted on an electronic musical instrument.

When the keys are pressed, the inertial forces of all the components that make up the keyboard act in a composite manner, and as a result the player can feel what gathers at the tip of the key as the inertial force of the key. The mass that gives the inertial force of is commonly called the equivalent mass. This equivalent mass may be provided directly under the key tip, but this would make the entire keyboard device too heavy. Therefore, it is required to provide a hammer action mechanism to obtain a large expansion ratio. In a keyboard device mounted on an electronic musical instrument, it is appropriate to aim at the expansion ratio of 1: 3.

[0007]

By the way, in the part size range of keyboard parts, the part precision is similar regardless of the size of the part. It is desirable to expand the movement of the tip of the key as it is to make it a movement of the hammer, but in reality, a plurality of parts are interposed therebetween, and the stroke amount is repeatedly reduced / enlarged. As long as the parts have similar accuracy, the error added when the stroke is reduced becomes large when the stroke is enlarged. Therefore, it is desirable to avoid extreme reduction / enlargement.

When the stroke of the key tip is determined, the stroke of the center of gravity (mass point) of the hammer is determined from the enlargement ratio. Therefore, in order to satisfy the above-mentioned extreme reduction / enlargement, it is necessary to increase the hammer as much as the space allows, and to use the center of gravity of the hammer as the swing fulcrum in order to obtain a feeling of popping when pressing a key. On the other hand, it is required to be arranged on the side opposite to the key tip (key fulcrum side). Japanese Utility Model Laid-Open No. 4-120999 and Japanese Utility Model Laid-Open No. 4-114409 described above.
The keyboard device described in Japanese Patent No. 6 has a problem in this point because the center of gravity of the hammer is arranged on the key tip side with respect to the swing fulcrum.

The keyboard device described in Japanese Patent Laid-Open No. 4-303891 has a sufficiently large hammer and its center of gravity is located on the side opposite to the key tip with respect to the swing fulcrum. Since the position of the jack that transmits the key movement to the hammer is not sufficiently separated from the key fulcrum and the hammer fulcrum,
There is a problem in reducing / enlarging the stroke. The greater the distance from the key fulcrum, the greater the displacement of the jack, which increases the accuracy of the mechanical action. In the vicinity of the jack, a regulating button for abutting against the jack at the end of key depression and swinging it in the direction to release the engagement with the hammer (in the above-mentioned publication, the keyboard frame also has that function. Are required).

On the other hand, it is more advantageous that the key guide for restricting the left and right direction of the key as viewed from the player is provided farther from the key fulcrum. However, the keyboard device used for electronic musical instruments is required to be smaller than a piano, and each function is concentrated in a limited space, so if you try to satisfy these at the same time, both mechanisms (regulating button and There is a problem that the key guide will interfere. A first object of the present invention is to solve this problem, save space and parts, and improve performance. Further, an element that influences the touch feeling of the key is friction between the members forming the hammer action mechanism, and it is particularly necessary to reduce friction caused by sliding between the jack and the hammer and between the jack and the regulating button. A second object of the present invention is to reduce the friction and improve the key touch feeling.

[0011]

In order to achieve the first object, the keyboard device according to the present invention has a key provided so as to be swingable around a fulcrum portion with respect to a support member, and a pressing operation of the key. Is arranged so that its center of gravity moves with respect to the supporting member along with the pressing operation of the key, and the jack is displaced from the key through the jack with the pressing operation of the key. A mass body that swings by a transmitted force, is fixed to the support member, is inserted inside the front end portion of the key, and guides the swinging movement of the key during key operation. Abut the jack in the middle of the operation,
A key guide / regulating button for swinging the jack in a direction to disengage from the mass body is provided.

The keyboard device according to the present invention has the above-mentioned second aspect.
In order to achieve the above-mentioned object, a key that is swingably provided around a fulcrum portion with respect to a support member, a jack that is displaced and rotated in accordance with the pressing operation of the key, and a pressing operation of the key A mass body that is disposed so that its center of gravity moves with respect to the support member and that swings due to the force transmitted from the key through the jack when the key is pressed; And a regulating button which is provided to abut the jack during the operation of the key during the operation of the key and swing the jack in a direction to release the engagement with the mass body. Further, the rotation fulcrum of the jack and the contact portion of the jack and the regulating button are provided so as to be aligned in a substantially straight line.

Alternatively, in addition to the above, there is provided a repetition lever which is displaced and rotated in accordance with the pressing operation of the key and is biased by the biasing means so as to always contact the mass body, and the fulcrum of the key is provided. The portion, the swing fulcrum of the mass body, and the contact portion between the mass body and the jack or the repetition lever are provided so as to be aligned substantially in a straight line.

[0014]

According to the present invention, since the same member is used also as the key guide and the regulating button, it is provided with the jack in the vicinity of the tip of the key, which is largely separated from the fulcrum of the key, without interfering with other members. You can As a result, the position of the key in the left-right direction can be effectively controlled, and the enlargement ratio of the action mechanism of the mass body (hammer) can be increased without increasing the error.
In a limited space, various conditions described above can be cleared so that a key touch feeling very close to that of an acoustic piano can be obtained.

The fulcrum part of the key, the swinging fulcrum of the jack, and the contact part of the jack and the regulating button are
By arranging them so that they are aligned on a substantially straight line, it is possible to minimize the sliding of the contact portion between the jack and the regulating button and suppress the generation of frictional force. Further, the fulcrum portion of the key, the swing fulcrum of the mass body, and the abutting portion of the mass body and the jack or the repetition lever are provided so as to be substantially aligned, so that the mass body (hammer) is provided.
It is possible to minimize the sliding of the contact portion between the jack and the repetition lever and the generation of the frictional force. These make it possible to realize a key touch feeling that is very similar to that of an acoustic piano.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a sectional view taken along the longitudinal direction of a black key in a non-key-depressed state of a keyboard device showing an embodiment of the present invention, and FIG. 2 is a diagram showing a state of a key depressing end when the key is strongly depressed.

First, the structure of the action mechanism of the keyboard device will be described with reference to FIG. Reference numeral 1 denotes a keyboard frame which is a support member, and is attached and fixed by bolts and nuts 3 on a shelf plate 2 which is a keyboard device support base of a musical instrument housing. The keyboard frame 1 is formed by sheet metal working of a metal plate such as an iron plate, and has a constant width and extends in the key arrangement direction.
It is formed in a downward channel shape composed of a and a front vertical portion 1b bent at a right angle from its front edge and a rear vertical portion 1c bent at a right angle from its rear edge.

At the rear end of the horizontal portion 1a of the keyboard frame 1, the supporting member side fulcrum portion 4 of each key is arranged along the key arrangement direction.
Are formed by resin outsert molding. 5
B is a black key formed of resin, and a key side fulcrum portion 6 formed at the rear end thereof is fitted into the support member side fulcrum portion 4 so as to be swingable around the fulcrum P with respect to the keyboard frame 1. Supported. The white key 5W shown by a virtual line in the figure is also different in length and shape from the black key 5B, but the rocking fulcrum portion and the action mechanism according to the present invention have the same configuration as the black key 5B. In the following description, the white key 5W and the black key 5B are collectively referred to as "key 5".

The supporting member side fulcrum portion 4 and the key side fulcrum portion 6
Allows the rocking of the key 5 with respect to the keyboard frame 1 in the key pressing direction (vertical direction) and the key width direction (direction orthogonal to the paper surface), and the rolling (centering on the axis line along the longitudinal direction of the key 5) It has a structure that prevents the rotation. That is,
The supporting member-side fulcrum portion 4 and the key-side fulcrum portion 6 make line contact in the height direction of the key 5 on one of the contact surfaces on both sides thereof, and the point contact at the fulcrum P or the fulcrum P on the other contact surface. It is in contact with a small area around the center.

A hammer support piece 7 corresponding to each key 5 is formed by cutting and raising the lower surface of the intermediate portion of the horizontal portion 1a of the keyboard frame 1.
The hammer 8 which is a mass body is supported on each of the hammer support pieces 7 by a shaft 9 so as to be swingable around the hammer 8. The hammer 8 has a bifurcated front side (left side in the drawing) made of resin from the shaft supporting portion 8a, a lower arm portion 8b extending in the key tip direction, and an upper arm portion 8c being the keyboard frame 1 It extends upward through the opening 1d formed in the horizontal portion 1a and is inserted into the key 5. The tip portions of the respective arm portions 8b and 8c are buffer-coated with a soft resin or the like.

A weight portion 8d, which is formed by wrapping a heavy metal material such as an iron material or the like in a resin, is extended rearward from the shaft support portion 8a of the hammer 8, and a rear end portion 8e thereof is on the rear side of the keyboard frame 1. It projects from the vertical portion 1c through an opening 1e formed therein. Therefore, the center of gravity of the hammer 8 is considerably close to the rear end portion 8e. And the key side fulcrum part 6
A key spring 10, which is a leaf spring, is attached between the key 5 and the hammer 8 so as to give the key 5 and the hammer 8 slightly right-handedness.

A lower limit stopper 11 for the hammer 8 also functions as a lower limit stopper 11 for the hammer 8 on the rear side of the rear vertical portion 1c of the keyboard frame 1 and an upper limit stopper having a sharp lower end for the lower surface of the rear end of the horizontal portion 1a. A repulsion member 12 is provided. The lower limit stopper 11 is a pad such as rubber or soft resin or felt, and the repulsion member 12 is a member having elasticity such as rubber or soft resin.

A repetition lever support piece 13 is hung downward from a side surface of an intermediate portion of the key 5 in the longitudinal direction, and is projected downward through an opening 1f formed in a horizontal portion 1a of the keyboard frame 1, and a shaft 14 is attached to the tip portion thereof. The repetition lever 15 is swingably supported. The repetition lever 15 extends slenderly toward the front side (left side in the figure), and its tip portion protrudes forward through an opening 1g formed in the front vertical portion 1b of the keyboard frame 1 and is provided on the front side of the front vertical portion 1b. The pad 16 made of rubber, felt, or the like is brought into contact with the pad 16 to lock the left turning movement.

A slit 15a is formed in the middle portion of the repetition lever 15 along the longitudinal direction thereof for inserting a jack 17 described later, and the lower surface of the slit forming portion engages with the arm portion 8b of the hammer 8. A substantially T-shaped jack 17 is swingably supported by a shaft 18 inside the key 5 near the tip thereof, and a main arm 17a thereof is formed on a horizontal portion 1a of the keyboard frame 1. It extends downward through the opening 1f, and its tip portion is inserted into the slit 15a of the repetition lever 15 so that the hammer 8
Engages with the arm portion 8b.

A repetition spring (a leaf spring which is an elastic material) 19 is engaged between the jack 17 and the repetition lever 15 to give the jack 17 and the repetition lever 15 a left-handed turning characteristic in the figure. Instead of the spring 19, the free end portion (tip portion) of the repetition lever 15 may be made heavy so as to give the habit of returning in the left-handed direction. Jack 17
The sub-arm 17b extending rearward from the shaft support portion abuts on an abutment surface 5a provided in the key 5 along the longitudinal direction so that the left turning movement is locked and the sub-arm 17b moves integrally with the key 5.

Further, the key 5 is inserted inside the front frame of the key 5 below the sub-arm 17c extending forward from the pivotal part, and guides the swinging direction of the key 5 when the key is operated. A key guide / regulating button 20 is erected on the way to abut on the sub arm 17c of the jack 17 to swing the jack 17 in the direction to release the engagement with the hammer 8 (clockwise in the figure). This button 20
Is provided with an abutting portion at the upper end thereof, and the side surfaces on both sides in the key arranging direction have a double-molded structure provided with a sliding material that is slippery, or grease is applied. The upper surface of the sub-arm 17b of the jack 17 and the lower surface of the sub-arm 17c are also buffer-coated with a soft resin or the like. Reference numeral 21 denotes a key stopper made of a cushioning material such as a felt provided near the front end of the horizontal portion 1a of the keyboard frame 1 along the arrangement direction of the keys 5.

Then, as shown in FIG. 2, when the sub-arm 17c of the jack 17 is brought into contact with the key guide / regulating button 20 by pressing the key, the contact portion Q thereof.
Are arranged substantially on a straight line L1 connecting the swing fulcrum P of the key 5 and the center of the shaft 18, which is the swing fulcrum of the jack 17. FIG. 2 shows a state in which the engagement between the jack 17 and the hammer 8 which is a mass body is disengaged and the key 5 is slightly pushed in. Just before or immediately after the disengagement, the above three points (P , 18, Q) are aligned.

Further, the contact portion S (FIG. 1) between the hammer 8 and the jack 17 or the repetition lever 15 also has the key 5
Are provided so as to be substantially lined up on a straight line L2 that connects the swing fulcrum P of 4 and the center of the shaft 9 that is the swing fulcrum of the hammer 8. FIG.
In the non-key-depressed state shown in Fig. 2, the contact portion S is located slightly above the straight line L2, but the contact portion S descends as the key is depressed, and the hammer 8 is moved as shown in Fig. 2. Immediately before leaving the jack 17 and the repetition lever 15, the abutting portions S of both are located on the straight line L2. FIG. 2 shows a state in which the above-mentioned three points (P, 9, S) are aligned on a straight line and the key 5 is slightly pushed in.

Next, the operation of this keyboard device will be described. In the non-key-depressed state shown in FIG. 1, the hammer 8 which is a mass body is rotated right by its own weight, and its rear end 8e is in contact with the lower limit stopper 11, and its arm 8b has the repetition lever 1.
5 and jack 17 to push them up, key 5
Is returned to the raised position. Repetition lever 1
5 is constantly urged by a repetition spring 19 so as to always contact the hammer 8.

From this state, when a finger is brought into contact with the key 5 and pushed slowly in the direction of arrow A, the finger 5 is moved along with the key 5 and the jack 17
Also gradually descends and pushes down the arm portion 8b of the hammer 8 with the tip of the main arm 17a, so that the hammer 8 rotates counterclockwise in the figure, but due to the inertial force, a large reaction force is generated and a strong resistance is exerted on the finger. I feel. Repetition lever 1
5 is rotated leftward while being in contact with the arm portion 8b of the hammer 8 by the biasing force of the repetition spring 19,
When the tip end contacts the pad 16, the left turning motion is stopped.

Eventually, the sub arm 17c of the jack 17
When the key comes into contact with the key guide / regulating button 20, the jack 17 turns to the right as the shaft 18 descends, and the slit 15a of the repetition lever 15 moves.
The main arm 17a, which slightly projects from and presses the arm portion 8b of the hammer 8, is separated from the arm portion 8b. As a result, the hammer 8 releases the left-handed turning force by the key depression, turns slightly rightward by its own weight, and its arm portion 8b comes into contact with the repetition lever 15 and is stopped. At this time, the hammer 8 is released from the interlocking with the key 5 and the key interlocking member, so that the resistance feeling by the hammer 8 is temporarily reduced and a let-off feeling (progressive feeling) is obtained.

When the key 5 is pushed harder than a certain amount, the jack 17 pivots as shown by the arrow B in FIG. 2 to come off the hammer 8, and then the hammer 8 continues to turn left by its inertia, and the weight portion. 8d collides with the repulsion member 12 and is repulsed, and rebounds as shown by arrow C, and then the arm 8c abuts the contact surface 5a of the key 5 in the direction of arrow D to perform a back check. The check mechanism stops the movement of the hammer 8. As a result, a dynamic touch feeling at the time of a hard key press and a mass release feeling (dynamic let-off feeling) at the end of the key press can be obtained.

As described above, according to this keyboard device, the center of gravity of the hammer 8 is located far away from the shaft 9 serving as the swing fulcrum to the side opposite to the tip of the key 5, and the shaft 9 of the hammer 8 is further separated. Is also far away from the rocking fulcrum P of the key 5, and the jack 17
Can be further charged and separated from the shaft 9 to the tip of the key 5, so that a large enlargement ratio can be obtained without impairing accuracy, and a sufficient sense of mass can be obtained. Since the key guide / regulating button 20 also functions as a key guide and a regulating button with one member, both members do not interfere with each other in the vicinity of the tip of the key 5, and the key 5 can be effectively moved in the left-right direction. It is possible to regulate the position of (1) and guide it in the key pressing direction and rotate the jack 17 largely.

Further, the swing fulcrum P of the key 5 and the jack 17
Since the shaft 18, which is the swinging fulcrum, and the contact portion Q of the jack 17 and the key guide / regulating button 20 are provided so as to be aligned in a substantially straight line, the sliding at the contact portion Q is performed. The movement can be minimized and the generation of frictional force can be suppressed. Further, the swinging fulcrum P of the key 5, the shaft 8 which is the swinging fulcrum of the hammer 8, and the contact portion S between the hammer 8 and the jack 17 or the repetition lever 15 are provided so as to be substantially aligned. By doing so, it is possible to minimize the sliding at the contact portion S and suppress the generation of frictional force. As a result, it is possible to achieve smooth key operation and key touch feeling that closely resembles an acoustic piano.

In the above-mentioned embodiment, all the following three features which are characteristic of the present invention are implemented. Provide a key guide and regulating button. The rocking fulcrum of the key, the rocking fulcrum of the jack, and the abutting part of the jack and the regulating button should be arranged almost in line. The swinging fulcrum of the key, the swinging fulcrum of the hammer, and the contact portion between the hammer and the jack or the repetition lever should be provided so as to be substantially aligned. However, it is effective to implement these individually or in any combination.

When the keyboard device is used as a keyboard device for an electronic musical instrument, it goes without saying that it is necessary to provide a key switch which is turned on when a key is pressed to generate a key pressing signal or a touch response signal. Therefore, although the key switch is not shown in FIG. 1, the key switch unit 25 is attached to the rear vertical portion 1c of the keyboard frame 1 by screwing or the like, as shown by the phantom line in FIG. A photo interrupter may be provided as a key switch for each key, and the weight portion 8d of the hammer 8 of each key may be inserted into each photo interrupter.

In this case, when the hammer 8 is in the lowered position (position in which no key is depressed) shown in FIG. 1, the weight portion 8d shuts off the optical path of the photo interrupter and turns it off. As shown in FIG. 2, when the hammer 8 turns counterclockwise, the weight portion 8d can be retracted from the optical path of the photo interrupter of the key switch unit 25 and turned on. Of course, a dome type key switch operated by the key 5 or the hammer 8 directly or via an actuator, or a key switch of any other type may be provided.

In addition, the jack 17 in the above-described implementation
Can be attached to the keyboard frame 1 side, and the pivotal fulcrum of the hammer 8 which is a mass body may be provided on the key 5 side. Further, the keyboard device according to the present invention is not limited to the keyboard device of an electronic keyboard musical instrument such as an electronic piano or an electronic organ.
For example, a keyboard instrument that vibrates a sounding body such as a string or a diaphragm by a key operation directly or through an action mechanism, or opens and closes a valve to generate a blowing sound, or electrically amplifies the sound. It can also be applied to electric keyboard musical instruments that emit sound, as well as practice keyboard devices such as pianos and electronic pianos that have an action mechanism.

[0039]

As described above, according to the present invention, it is possible to compactly realize a keyboard device having a key touch feeling very similar to that of an acoustic piano with a relatively simple action mechanism. In particular, the key guide and the regulating button are integrated, saving space and parts and improving performance. Also,
The occurrence of friction at the sliding parts of the action mechanism is minimized, which enables a smooth key operation feeling and a smooth key operation.

[Brief description of drawings]

FIG. 1 is a sectional view taken along the longitudinal direction of a black key in a non-key-depressed state of a keyboard device showing an embodiment of the present invention.

FIG. 2 is a sectional view similar to FIG. 1, showing a state at the end of key depression.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Keyboard frame (support member), 2 ... Shelf plate, 4 ... Support member side branch part, 5B ... Black key, 5W ... White key, 5 ... Key, 6 ... Key side fulcrum part, 7 ... Hammer support piece, 8 … Hammer (mass body) 9
… Hammer shaft, 10… Key spring, 11… Lower limit stopper, 1
2 ... Repulsion member, 13 ... Repetition lever support piece, 1
4 ... Repetition lever shaft, 15 ... Repetition lever, 16 ... Pat, 17 ... Jack, 18 ... Jack shaft, 19 ... Repetition spring, 20 ... Key guide and regulating button, 21 ... Key stopper,

Claims (3)

[Claims] 1. A key provided swingably with respect to a supporting member around a fulcrum portion, a jack which is displaced and rotated in response to a pressing operation of the key, and the support in accordance with a pressing operation of the key. A mass body that is arranged so that its center of gravity moves with respect to the member, and that swings due to the force transmitted from the key through the jack when the key is pressed; It is installed inside the key near the front end of the key and guides the movement of the key in the swinging direction at the time of key operation, and abuts the jack during the operation to engage the jack with the mass body. A keyboard device characterized by being provided with a key guide / regulating button that swings in the direction of coming out of alignment. 2. A key provided so as to be swingable with respect to a supporting member around a fulcrum portion, a jack that is displaced and rotated in response to a pressing operation of the key, and the support is supported in accordance with a pressing operation of the key. A mass body that is disposed so that its center of gravity moves with respect to the member, and that swings due to the force transmitted from the key through the jack when the key is pressed, and is fixed to the support member. And a regulating button that abuts the jack during the operation of the key and swings the jack in a direction in which the jack is disengaged from the mass body, the fulcrum portion of the key, and A keyboard device, wherein a turning fulcrum of the jack and a contact portion of the jack and the regulating button are provided so as to be substantially aligned. 3. A key provided to be swingable with respect to a support member around a fulcrum portion, a jack which is displaced and rotated in response to a pressing operation of the key, and the support in accordance with the pressing operation of the key. A mass body that is disposed so that its center of gravity moves with respect to the member, and that swings due to the force transmitted from the key through the jack when the key is pressed, and is fixed to the support member. A key that abuts the jack during the operation of the key and swings the jack in a direction to release the engagement with the mass body; and a displacement button accompanying the pressing operation of the key. A rotation lever that is rotated and biased by the biasing means so as to always contact the mass body; and a fulcrum portion of the key, a swing fulcrum of the mass body, the mass body, and the jack or Match with the repetition lever A Department, the keyboard apparatus being characterized in that provided as substantially aligned on.