JPS62235986A - Keyboard unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a keyboard device used in electronic musical instruments and the like.

Conventional technology In recent years, electronic keyboard instruments have been improved so that they can produce performance expressions similar to those of acoustic pianos, and many of them are touch-sensitive instruments that control the sound produced according to the strength of the keystrokes and can vary the strength of the sound. It has become to. Along with this, emphasis has been placed on the feel of the keyboard's touch that is transmitted to the fingers of the performer, and there is a strong desire to create a keyboard that can provide a touch similar to that of a piano. However, on the other hand, for players accustomed to electronic organs, the touch of a piano may be too heavy and light.

Since keyboards that provide a pleasant touch feel are preferred, it has become necessary to realize a keyboard device for an electronic musical instrument that satisfies both requirements.

As a conventional technology for realizing keyboard devices for electronic musical instruments, there is a keyboard device in which weights are embedded in both ends of a keyboard that is rotatably supported around a fulcrum, and the balance of the weights creates a touch sensation. 〇The conventional keyboard device as mentioned above will be explained below with reference to the drawings.

FIG. 2 shows the configuration of a conventional keyboard device. Second
In the figure, 1 is a keyboard, which is rotatably supported approximately at the center by a support base 3 whose lower surface is fixed to a base plate 2.A lead weight 4 is placed on the keystroke side of the keyboard 1, and a similar weight 5 is placed on the opposite side. , 6.7 are embedded, a stopper 8 is provided on the lower surface of the keystroke side of the keyboard 1, and a cushion material 9 is provided on the lower surface of the opposite side.

The operation of the keyboard device configured as described above will be explained below.

The support stand 3 rotatably supports approximately the center of the keyboard 1, and the weight embedded in the keyboard 1 is lighter on the keying side, so the keyboard 1 is normally tilted backwards and stopped by the cushioning material 9. . When the performer hits this key, the keyboard 1 has a weight of 4
, 5, 6.7, the lower surface collides with the stopper 8 and stops. When you release your finger, the gravity of the weight will return it to its original state. As described above, it has been possible to arbitrarily set the touch feel of the conventional keyboard device by changing the size of the weight embedded in the keyboard 1 and how to balance it.

Problems to be Solved by the Invention However, with the above configuration, once the size of the weight is determined, it is difficult to switch between a heavy touch and a light touch. It was too heavy and unsuitable for players accustomed to electronic organs.

In view of the above-mentioned problems, the present invention provides a keyboard device that allows touch switching.

Means for solving the problem In order to achieve this object, the keyboard device of the present invention includes a keyboard whose one end is rotatably supported, and an air compression device such as a bellows or a dashpot connected to the underside of the keyboard. The open hole outlet of the air compressor is fixedly supported by a fixed part having a cavity inside, and the fixed part has a cavity in which a pipe and an air valve are connected, and the inside of the pipe has an outer diameter smaller than the inner diameter of the pipe. It has a structure in which a cylindrical weight is inserted that maintains a distance and can be reciprocated by air pressure.

Operation With this configuration, when the player hits a key on the keyboard, the air in the air compression device is compressed, and this compressed air is released from the opening and sent to the cavity of the fixed part.

When the air valve in the fixture cavity is closed, the compressed air pushes up the weight in the tube located in the fixture cavity. Here, if the cross-sectional area of the air compressor is S++, the cross-sectional area of the pipe is Sl, and the mass of the weight inside the pipe is m, then the gravity F moving to m
, is as shown in equation (1).

Fg= m fistg ・・・・・・
(1) Here, g is gravitational acceleration.

Assuming that the tube is placed at an angle of 0 from the horizontal plane,
Force component of gravity F in the angle θ direction 11g-Fg41no
In order to generate the balanced force F by the fingers at the key-pressing point, the magnitude of... (2) is required. That is, 81//s2 is called the acoustic transformation ratio and corresponds to the lever ratio of a mechanical lever.

If the cross-sectional area S2 of the tube is smaller than the cross-sectional area S1 of the air compressor, Sl>Sl, the acoustic transformation ratio becomes dog, and even though the mass m of the weight inside the tube is the same, a large reaction force F is exerted on the finger. feel. As described above, when the air valve is closed, the keyboard of this method has an effect equivalent to that of a conventional keyboard that uses a lever. In addition, the cylindrical weight installed inside the tube maintains a slit between its outer diameter and the inner diameter of the tube, and the amount of air that passes through this slit is small, so the compression caused by keystrokes is The weight moves up through the tube due to the air and maintains its position, and when you release your fingers from the keyboard, the weight forces compressed air into the air compressor, causing the keyboard to rise and return to its original state.

Next, when the air valve installed in the fixed part empty chamber is opened, the compressed air generated in the air compressor when a key is pressed is released from the air valve without raising the weight in the pipe, and acts on the keyboard. The reaction force becomes small.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of essential parts showing the configuration of a keyboard device in an embodiment of the present invention. In Figure 1, 1o is a keyboard, 1
Reference numeral 1 denotes a support base that supports the keyboard 1o rotatably around the rotating shaft 11&, 12 a base plate that fixes the support base 11, 13 a bellows attached to the lower surface near the tip of the keyboard 10, and 14 provided on the base plate 12. An opening for passing the bellows 13, 16 is a fixing part that fixedly supports the opening in the bellows 13, 16 is a cavity provided in the fixing part, and 17 is a tube connected to the cavity 16 of the fixing part 16, which is smaller than the inner diameter. It has an inlet 18 and an outlet 19. Reference numeral 20 is a cylindrical weight provided inside the tube 17, the outer diameter of which maintains a gap with the inner diameter of the tube 17, 21 is an air valve connected to the cavity 16, and 22 is the lower surface of the tip of the keyboard 1o. 23 is a coil spring provided between the end of the keyboard 10 and the spring fixing portion 24, and 25 is an opening provided on the board 12 through which the coil spring 23 is passed.

The operation of the keyboard device configured as described above will be explained below. First, when a player hits a key on the keyboard 10, the keyboard 10 starts to descend because one end is rotatably supported by the support stand 11. On the lower surface of the keyboard 10, a bellows 13, which is an air compression device, is fixedly supported at its opening by a fixed part 15, and as the keyboard 1o descends, the air within the bellows 13 is compressed. Compressed air generated within the bellows 13 is released from the opening and sent to the cavity 16 of the fixing part 15.

Here, when the air valve 21 provided in the cavity 16 is closed, the compressed air in the cavity 16 is sent to the pipe 17. A cylindrical weight 20 is provided inside the tube 17, and there is a slit between its outer diameter and the inner diameter of the tube 17, but if the slit is small enough, only a small amount of compressed air will pass through the slit. and
Compressed air raises weight 2Q. The force required to raise the weight 20 is transmitted to the keyboard 10 as a reaction force, and is perceived by the fingers as a touch sensation. As mentioned above, this reaction force corresponds to F in equation (2). During the keystroke process, which is the downward movement of the keyboard 10, the air within the bellows 13 continues to be compressed, and the downward movement is stopped when it collides with the stopper 22.

At this time, since the gap between the tube 17 and the cylindrical weight 2o is sufficiently small, the weight 2o remains stationary while maintaining the position raised during the key-pressing process. When you release your finger, the keying process is reversed,
Compressed air accompanying the descent of the weight 20 is sent into the bellows 13, raising the keyboard 1° and returning it to its original state.

Still, the diameters of the inlet 18 and outlet 19 of the tube 17 are smaller than the inner diameter of the tube 17, so the weight 2o does not jump out of the tube 17 and moves back and forth within the tube 17 in response to the movement of the keyboard 1o. Repeat. Next, when the air valve 21 provided in the empty chamber 16 is opened, the compressed air generated in the bellows 13 by the keystroke is released from the air valve 21 without raising the weight 2Q in the pipe 17, and is delivered to the keyboard 1o. The reaction force acting becomes small, and in the return process, the spring force of the bellows 13 returns to the original state.

The coil spring 23 provided between the end of the keyboard 1o and the spring fixing part 24 works to assist the return process of the keyboard 1o, but since the bellows 13 itself has spring properties,
Attach and remove as necessary. Further, although the bellows 13 is used in this embodiment, a dashpot may also be used. Further, the air valve 21 may be either an electrically controllable valve such as a solenoid valve, or a mechanical valve.

Effects of the Invention The present invention connects an air compression device to the lower surface of a keyboard that is rotatably supported around a fulcrum, fixes and supports the aperture outlet of the air compression device to a fixed part having a cavity inside, and fixes the keyboard. A pipe and an air valve are installed in the empty space, and a cylindrical weight is installed inside the pipe that moves reciprocally within the pipe using air pressure. The compressed air generated raises the weight inside the tube, which is then transmitted to the keyboard.

The reaction force caused by the rise of this weight creates the touch sensation of a piano, and when the air valve is open,
Compressed air is released from the air valve to achieve a very light organ touch feeling without raising the weight of the pipes.

As described above, according to the keyboard device of the present invention, it is possible to switch the touch feeling, which was previously impossible, by opening and closing the air valve, and it has the touch feeling of both a piano and an organ.
Depending on the degree of opening and closing of the air valve, it is possible to create a keyboard device that can produce an intermediate touch between a piano and an organ.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part showing the structure of a keyboard device according to an embodiment of the present invention, and FIG. 2 is a sectional view of a main part showing the structure of a conventional keyboard device. 1o... Keyboard, 13... Bellows, 1
5...Fixed part, 16...Vacant room, 17.
...Tube, 2o...Weight, 21...
・Air valve. Name of agent: Patent attorney Toshio Nakao and one other person IQ
--- Hammer 13-1 Head knowledge 15- Fixed part π --- 1 ri 21 -- Kazutomi Kisho

Claims (4)

[Claims] (1) A keyboard whose one end is rotatably supported, an air compression device coupled to the underside of the keyboard, a fixed part that fixedly supports the aperture outlet of the air compression device and has a hollow space inside, and a fixed part of the fixed part. A tube having an outer diameter that maintains a narrow gap with the inner diameter of the empty chamber and into which a cylindrical weight that is capable of reciprocating movement is inserted, and an air valve that is provided in the fixed part and that can vary the air pressure. A keyboard device characterized by: (2) The keyboard device according to claim 1, wherein the air compressor is a bellows or a dashpot. (3) The keyboard device according to claim 1, wherein the air valve is electrically controllable. (4) The keyboard device according to claim 3, wherein the air valve is a solenoid valve.