JPH0711756B2 - Keyboard device for electronic musical instruments - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a keyboard device for electronic musical instruments.

2. Description of the Related Art In recent years, electronic keyboard musical instruments have been improved so that they can reproduce musical performances similar to those of acoustic pianos. In terms of sounds, many of them are touch-sensitive methods that control the generated sound according to the strength of keystrokes, and can produce that strength. It has become to. Along with this, the touch feeling of the keys transmitted to the player's finger is emphasized, and it has been strongly desired to realize a keyboard device for an electronic musical instrument that can provide a touch close to that of a piano.

As a conventional technique for realizing such a keyboard for an electronic musical instrument, for example, as shown in Japanese Utility Model Publication No. 50-10752, a magnet or electromagnet is attached to the lower surface of the keyboard, and an electromagnet or an electromagnet is mounted on a frame facing the keyboard. With a magnet
There is a keyboard device for an electronic musical instrument that controls the touch of the keyboard by the magnetic force between a magnet and an electromagnet.

Hereinafter, the conventional keyboard device for an electronic musical instrument as described above will be described with reference to the drawings.

FIG. 5 shows the configuration of a conventional keyboard device for an electronic musical instrument. In FIG. 5, reference numeral 1 denotes a keyboard, one end of which is rotatably supported by a support plate 3 provided at the end of the frame 2, and between the keyboard 1, the end and the lower part of the support plate 3, A coil spring 4 is provided. Reference numeral 5 denotes a permanent magnet fixed to the lower surface of the central portion of the keyboard 1, and an electromagnet including a pole piece 6 and an exciting coil 7 is attached to the frame 2 so as to face the permanent magnet 5. Both ends 8 of the exciting coil 7,
A DC power supply 11 is connected to 9 via a polarity switching switch 10.

Regarding the keyboard device for electronic musical instruments configured as described above,
The operation will be described below.

When the player hits the keyboard 1, the keyboard 1 is rotatably supported by the support plate 3, so that the tension of the coil spring 4 provided between the end of the keyboard 1 and the lower portion of the support plate 3 is resisted. Then, the keyboard 1 descends. A permanent magnet 5 is fixed to the lower surface of the central portion of the keyboard 1, and an electromagnet composed of a magnetic pole piece 6 and an exciting coil 7 is attached to the frame 2 so as to face the permanent magnet 5. Permanent magnet 5
The distance between the pole piece 6 and the electromagnet including the exciting coil 7 becomes narrower. Since both ends 8 and 9 of the exciting coil 7 are connected to the DC power supply 11 via the polarity switching switch 10,
By operating the polarity switching switch 10, the touch of the key can be controlled. That is, when the polarity switching switch 10 is off, no current flows through the exciting coil 7, the magnetic pole piece 6 does not operate as an electromagnet, and the permanent magnet 5 provided on the lower surface of the central portion of the keyboard 1 does not have the magnetic pole piece 6. Because it is attracted to, the touch of the key is a little light. On the other hand, when the polarity switching switch 10 is turned on, a current flows through the exciting coil 7 to generate an electromagnetic force, and the pole piece 6 operates as an electromagnet. The polarity of the electromagnet generated in the pole piece 6 can be selected according to the direction of the current flowing in the exciting coil 7. That is, the polarity can be determined by operating the polarity switching switch 10. With respect to the polarity of the permanent magnet 5 provided on the lower surface of the keyboard 1, the pole piece 6
In the case where the polarities generated in 1 are different polarities, the two are attracted to each other, so that the keyboard 1 is strongly attracted to the lower side, and the touch of the key can be made considerably light. Further, when the polarity changeover switch 10 is operated and the polarities generated in the magnetic pole pieces 6 are the same as the polarities of the permanent magnet 5, they repel each other and the key touch becomes heavy.

As described above, the permanent magnet 5 provided on the lower surface of the keyboard 1 and the pole piece 6 and the exciting coil 7 are attached on the frame facing the permanent magnet 5, and the polarity changeover switch 10 is interposed between the coil ends 8 and 9 of the exciting coil 7. A keyboard device for an electronic musical instrument, in which various touch feelings can be obtained by operating the polarity switching switch 10 as a configuration for connecting a direct current power source.

Problems to be Solved by the Invention Fig. 4 shows the reaction force received from the keyboard, that is, the touch feeling, which the finger receives from the keyboard in the keystroke process from the touch of the finger to the descent of the keyboard to the stop until it stops. This is a measurement for a grand piano, where the horizontal axis represents the movement stroke of the keyboard and the vertical axis represents the reaction force. Looking at the above characteristics, the reaction force that the finger receives from the keyboard is the reaction force generated when the finger touches the keyboard (hereinafter referred to as the attack reaction force) and the reaction force generated when the hammer moves (hereinafter referred to as the hammer movement reaction force). Call),
It can be roughly divided into three types, the reaction force generated when stopped by a stopper (hereinafter referred to as the stop reaction force). If this is expressed by the touch feeling on the finger, the attack reaction force is felt as an impact force, and is greatly affected by the speed of the player's finger, that is, the playing style, and the more strongly you play, the greater the impact. The hammer movement reaction force, which is generally expressed as heavy or light, is a characteristic peculiar to an acoustic piano that produces a sound when the hammer strikes a string. It is also the main factor that causes the difference. The stop reaction force is perceived as an impact force like the attack reaction force, and its magnitude depends on the keystroke speed.

As is clear from the above characteristics, it is necessary to control the movement of the keyboard in a complicated manner in order to give the touch feeling of the piano.
Therefore, it has been difficult to obtain the touch feeling of the acoustic piano with the above-described conventional configuration in which the movement of the keyboard is simply controlled by the polarity switching switch.

Furthermore, in the above-mentioned conventional example, the movement of the keyboard is controlled by the magnetic force between the permanent magnet and the electromagnet. Therefore, when the gap between the permanent magnet and the electromagnet is large, that is, the keyboard where the mutual magnetic force is hard to reach rises. To control the movement of the keyboard near the cut position, use a permanent magnet with a large shape and large magnetomotive force, and as an electromagnet, take measures such as passing a large current through the exciting coil to control the magnetic force. It had to be large enough. However, it is difficult to increase the size of the permanent magnet in terms of space because the dimensions between the keyboards are fixed, and using a magnet material with a large magnetomotive force makes it extremely expensive, resulting in a significant cost increase. Was there. On the other hand, in order to strengthen the magnetic force of the electromagnet, passing a large current through the exciting coil requires a large power output as a power source and causes damage to the exciting coil due to heat generation, which is not practical. It was

In view of the above problems, the present invention provides a keyboard device for an electronic musical instrument, which is very close to the touch feeling of an acoustic piano and is low in cost.

Means for Solving the Problems To achieve this object, a keyboard device for an electronic musical instrument according to the present invention is provided with a bellows or a bellows held by a holder at a fixed end at one end of a keyboard rotatably held around a fulcrum. An air compression device such as a dashpot is connected, and at the end of this air compression device, a plurality of pores whose diameters or lengths are gradually changed are provided, and each pore outlet has a piezoelectric type, an electromagnetic type, or a dynamic type. An air valve constituted by an electric actuator is provided, and each air valve is provided with a control circuit for electrically controlling its movement.

Operation With this configuration, an air compression device held by a holder is connected to one end of the keyboard, a plurality of pores are provided at the end of the air compression device, and an electric power is controlled by a control circuit at each pore outlet. Since all the air valves are electrically input in the direction to close the air flow from the pore outlet, when the performer taps the keyboard, The air in the air compressor expands, and the keyboard is braked against the movement of the finger, and the touch feeling becomes very heavy.

On the other hand, when the air valve is operated by the electric input from the control circuit in the direction to open the pore outlet of the air compression device that has been closed until then, the air in the air compression device hardly expands and the keyboard The movement is not braked and a very light touch feeling can be realized. Here, the air compressor has a plurality of pores, the diameter or length of the pores is changed stepwise, and the number of openings and closings is controlled by the air valve provided at each pore outlet. When arbitrarily set by the control circuit, the air in the vicinity of the pore outlet naturally flows only through the open pores. As is well known, when air passes through pores, braking due to viscous resistance occurs, and the movement of the keyboard can be controlled by the magnitude of braking. As described above, since the diameter or length of each pore is changed stepwise,
The smaller the diameter or the longer the length, the larger the viscous resistance becomes, and the viscous resistance is weighted by each pore. Therefore, for example, if the number of pores is 4, 4 bits, that is, 16 kinds of viscous resistance can be obtained, and the movement of the keyboard can be controlled by 4 bits, and 16 kinds of touch feeling can be obtained. If the control circuit controls the movement of the keyboard and the movement of the air valve in sequence, complicated characteristics such as the hammer movement reaction force, which is a characteristic peculiar to the acoustic piano shown in FIG. 4, can be easily obtained. It is possible to realize a keyboard device for an electronic musical instrument that has a touch feeling similar to that of an acoustic piano.

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

FIG. 1 is a cross-sectional view of an essential part showing the configuration of a keyboard device for an electronic musical instrument in an embodiment of the present invention, and FIG. 2 is a partly extracted. In FIG. 1, reference numeral 12 is a keyboard, 13 is a support base whose one end is fixed to a fixed end and rotatably supports substantially the center of the keyboard 12, and 14 is a coil spring provided between the keyboard 12 and the fixed end. , 15 is a bellows whose one end is fixed to the keyboard 12, 16 is a holder for holding the opening of the bellows 15, 17 is a plate fixed to the lower surface of the holder 16, and 18 is a holder 16 at the opening of the bellows 15. The vacant chamber 19 formed by the plate 17 is a pore provided in the plate 17, and an air compression device 20 is formed by the above components.

21 is a fixture for fixing the air compressor 20 to the fixed end, 22
Is an air valve of a piezoelectric actuator fixed to the end 23 of the plate 17, 24 is a gap provided between the pore 19 of the air compression device 20 and the air valve 22, and 25 and 26 are electric input terminals of the air valve 22. , 27 are control circuits connected to the electric input terminals 25, 26.

The operation of the keyboard device configured as described above will be described below. First, when the performer hits the keyboard 12, the keyboard 12 is rotatably supported at its substantially central portion, so that the tension of the coil spring 14 provided between the end of the keyboard 12 and the fixed end is resisted. Then, the other end of the keyboard 12 rises. On the lower surface of the end portion of the keyboard 12, a bellows 15 whose opening is held by a holder 16, a plate 17 fixed to the lower surface of the holder 16, a vacant chamber 18 formed by the holder 16 and the plate 17, and further, Holes 19 in plate 17
The air compression device 20 constituted by the above is coupled, and the whole of the air compression device 20 is fixed to the fixed end by the fixture 21, and one end of the pore 19 of the air compression device 20 has an end 23 of the holder 16. Since the air valve 22 of the piezoelectric actuator that is fixedly held on the
In the state in which a gap is maintained between, and, that is, in the state where the air near the outlet of the pores 19 easily flows into the bellows 15, the air in the bellows hardly expands, and the movement of the keyboard 12 is damped. It can realize a very light touch feeling. On the other hand, in this embodiment, since the air valve 22 is an actuator composed of a bimorph type piezoelectric element, the electric input from the control circuit 27 applied to its electric input terminals 25 and 26 causes the air valve 22 to have a structure as shown in FIG. 2 (a). In addition, it can be bent and deformed in a direction to close the outlet of the pore 19 of the air compression device 20 which has been opened until then. When the keyboard 12 is tapped in this state, the air in the bellows 15 expands, and the movement of the keyboard 12 is braked, resulting in a very heavy touch.

In the above two examples, the case where the extreme control is performed has been described, but as shown in FIG. 2 (b), the air compressor 20 has a plurality of pores, 19a, 19b, 19c in this embodiment. There are three air valves, and a plurality of air valves 22a, 22b, 22c are provided, and control circuits 27a, 27b, 27 for controlling these are provided.
If c is provided, the movement of the keyboard 12 can be controlled more finely, and its operation will be described below.

Air valves 22a, 22b, 22c are provided at the outlets of the pores 19a, 19b, 19c, respectively.
Is provided. Therefore, the air valves 22a, 22b, 22c can be operated by the electric input from the control circuits 27a, 27b, 27c to arbitrarily set the outlets of the pores 19a, 19b, 19c to the open or closed states.

When the keyboard 12 is tapped, the air near the openings 19a, 19b, 19c flows in only through the open pores. The air has pores 19a,
When passing either 19b or 19c, it becomes viscous resistance and brakes the movement of the keyboard 12. Further, in this embodiment, each pore 19
Since the diameters of a, 19b, and 19c are changed in a stepwise manner, the magnitude of viscous resistance also varies depending on the diameter. As a result, the viscous resistance is weighted by each pore, and as in the present embodiment, the number of pores is set to 3, and the relation of the sizes of the respective diameters la, lb, lc is la < If lb <lc,
By controlling the air valves 22a, 22b, 22c by the control circuits 27a, 27b, 27c, 3 bits, that is, 8 kinds of viscous resistance can be obtained,
It is possible to control 12 movements with 3 bits.

As described above, according to this embodiment, the three small holes 19a having different diameters of the air compressor 20 attached to the lower end surface of the keyboard 12 are provided.
Connect the outlets of 19b and 19c to the air valves 22a and 22 of the piezoelectric actuator.
By opening and closing b, 22c, changing the viscous resistance exhibited by the air flow passing through any of the pores 19a, 19b, 19c,
By controlling the movement of the keyboard 12, eight types of touch feeling can be obtained. Although the diameter of the pores is changed stepwise in the present embodiment, the length of the pores may be changed stepwise.
If all of the pores have the same diameter or length, four types of touch feeling can be obtained.

Although the piezoelectric actuators are individually provided as air valves in this embodiment, as shown in FIG.
Attach the piezoelectric elements 29a, 29b, 29c to both sides of the lead wires 30a, 3b.
It is also possible to use an integrated piezoelectric actuator in which both sides are connected by 0b and 30c. In this case, the air valve can be handled as a single component, which facilitates assembly.

Further, in the present embodiment, the expansion and contraction of the bellows was used to generate the air flow, but the same effect can be obtained as a dashpot. Further, in this embodiment, the piezoelectric actuator is used as the air valve, but the air valve may be constituted by an electromagnetic or electrodynamic actuator.

EFFECTS OF THE INVENTION The present invention is that an air compression device held at a fixed end is coupled to one end of a keyboard, a plurality of pores having different diameters are provided in this air compression device, and an air valve is arranged at the pore outlet. By applying electrical input from the control circuit, opening and closing any pore outlet, and changing the viscous resistance of the air flow passing through the pore, you can get an arbitrary touch feeling. By sequentially controlling the movement of the
Complex characteristics such as the reaction force of the hammer movement shown in the figure can be easily obtained, and a keyboard device for an electronic musical instrument that is very close to the touch feeling of an acoustic piano can be realized. Further, in order to obtain an effective force in the means for generating the magnetic force between the permanent magnet and the electromagnet in order to control the movement of the keyboard as in the conventional example, the permanent magnet having a large shape or magnetomotive force or the excitation of the electromagnet is required. It was necessary to pass a large current through the coil, which was not feasible due to space problems and cost increase. However, in the present invention, a slight movement of the air valve causes viscous resistance of the air flow passing through the pores. It is possible to obtain a sufficient force for braking the keyboard simply by changing the value of, and there is no component that causes an increase in cost. Therefore, it is possible to make a keyboard for a practical and low-cost electronic musical instrument.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part showing the configuration of a keyboard device for an electronic musical instrument according to an embodiment of the present invention, FIG. 2 (a) is a local cross-sectional view thereof, and FIG. 2 (b) is a partial cutaway thereof. The rear view and FIG. 3A are plan views of the electromagnetic actuator of the present invention.
FIG. 1B is a side view of the same, FIG. 4 is a keystroke characteristic diagram of a grand piano, and FIG. 5 is a cross-sectional view of essential parts showing a configuration of a conventional keyboard device for an electronic musical instrument. 12 ... keyboard, 15 ... bellows, 19,19a, 19b, 19c ... open hole, 20 ... air compression device, 22,22a, 22b, 22c ... air valve,
27,27a, 27b, 27c …… Control circuit.

Claims (5)

[Claims] 1. A keyboard rotatably supported about a fulcrum, an air compressor held by a holder at a fixed end is connected to one end of the keyboard, and a plurality of terminals are provided at the end of the air compressor. An electronic musical instrument characterized in that a fine hole is provided, an air valve whose movement can be controlled by an electric input is provided at each of the fine hole outlets, and a control circuit for controlling the electric input is provided at an input terminal of the air valve. Keyboard device. 2. The keyboard device for an electronic musical instrument according to claim 1, wherein the air compression device is a bellows or a dashpot. 3. The keyboard device for an electronic musical instrument according to claim 1, wherein the air valve is a piezoelectric, electromagnetic or electrokinetic actuator. 4. The first aspect of the present invention is characterized in that a plurality of pore diameters at the end of the air compressor are changed stepwise.
A keyboard device for an electronic musical instrument according to the item. 5. The keyboard device for an electronic musical instrument according to claim 1, wherein the length of a plurality of pores at the end of the air compressor is changed stepwise.