WO2018079642A1

WO2018079642A1 - Keyboard musical instrument

Info

Publication number: WO2018079642A1
Application number: PCT/JP2017/038652
Authority: WO
Inventors: 善哉西村
Original assignee: ヤマハ株式会社
Priority date: 2016-10-31
Filing date: 2017-10-26
Publication date: 2018-05-03
Also published as: JP2020016670A

Abstract

Provided is an electronic keyboard musical instrument that can emit realistic sounds without sacrificing the design of the musical instrument as a whole. The keyboard musical instrument is provided with: a musical instrument housing 2; a keyboard 11 disposed at the front of the musical instrument housing 2; a sound source for providing an electrical signal according to operation of the keyboard 11; a right vibrating plate 16 and a left vibrating plate 17 provided as parts of an upper surface 10a, which serves as an exterior surface, of a top plate 10 of the musical instrument housing 2; and a right transducer and a left transducer provided on the back surface of each of the vibrating plates 16, 17. Each transducer generates vibration according to the electrical signal provided by the sound source, and that vibration is transmitted to each respective vibrating plate from the back surface. Thus, each vibrating plate vibrates and emits sound according to the electrical signal.

Description

Keyboard instrument

The present invention relates to a keyboard instrument that generates a sound in response to an operation of the keyboard, and relates to a keyboard instrument that can reproduce a realistic sound by emitting sound from the exterior of the instrument casing.

Conventionally, as an electronic keyboard musical instrument using a substitute for this type of cone speaker, a musical instrument casing in which a keyboard, a sound source device, and a high-pitched speaker are accommodated, and a shelf board disposed at the bottom of the musical instrument casing And a vibration exciter fixed to the lower surface of the shelf board are known. The sound source device outputs an electrical signal based on the performance by the keyboard, the electrical signal is amplified by an amplifier, and the amplified electrical signal is supplied to the vibrator. And an exciter vibrates a shelf board and a shelf board makes a sound as a sound board (patent document 1).

JP 2008-292738 (abstract, FIG. 1).

However, the above-described conventional electronic keyboard instrument uses an idea based on the principle that the string vibration of an acoustic instrument is transmitted to the instrument casing and the instrument casing vibrates to produce sound. Since it is a structure that vibrates the shelf of an electronic keyboard instrument that does not vibrate, it was difficult to emit realistic sounds.
In particular, it has been difficult to reproduce high-frequency sounds with a thick shelf board. Furthermore, since the vibrator is fixed to the lower surface of the shelf board, it is difficult to deliver a high-frequency sound toward the player.
In addition, a configuration in which a cone speaker that emits high-frequency sound is externally attached to the instrument housing has been used in the past, but if you want to imitate the design of an acoustic instrument, it is said that this cone speaker is in the position where it is observed That detracts from the overall design of the instrument. However, if the cone speaker is installed inside the instrument housing and a tone escape (hole) is provided to emit the sound to the outside, the sound will not be emitted directly. The quality was impaired.

Therefore, the present invention has been proposed to solve the above-described problems, and an object of the present invention is to provide a keyboard instrument that can emit realistic sounds without impairing the overall design of the instrument. And

In order to achieve the above-described object, a keyboard musical instrument includes a musical instrument casing, a keyboard arranged at the front of the musical instrument casing, a sound source that supplies an electric signal in accordance with the operation of the keyboard, and an exterior surface of the musical instrument casing. And a vibration generating portion provided on the back surface of the diaphragm.

As described above, the keyboard instrument is provided with a diaphragm that emits a sound corresponding to an electric signal as a part of the exterior surface of the instrument casing, so that the design of the entire instrument is not impaired. Sound can be emitted.
In addition, since the diaphragm vibrates on the surface, sound attenuation according to the distance from the sound source is less than that of the point sound source, so that the sound can be efficiently delivered to the player and audience.

In the keyboard instrument, the exterior surface of which the diaphragm is a part is the top surface of the roof plate.
That is, since sound is emitted from the diaphragm provided as a part of the upper surface of the roof plate, a wide sound can be emitted.
Moreover, there is no need to form a tone escape in the instrument housing.

In the keyboard instrument, the exterior surface of which the diaphragm is a part is a surface facing the performer.
That is, since the sound is emitted from the diaphragm provided as a part of the surface facing the performer, it is not necessary to emit the sound via the tone escape, so that the sound can be efficiently delivered to the player and the audience.
Moreover, there is no need to form a tone escape in the instrument housing.
The keyboard instrument further includes a plurality of vibration generating units as the at least one vibration generating unit provided on a back surface of the diaphragm, and the plurality of vibration generating units include a plurality of keys of the keyboard. Are arranged in the first direction in which are arranged.
The keyboard instrument has a music stand attached to the upper surface of the diaphragm, and the plurality of vibration generators are respectively arranged at positions sandwiching the music stand in the first direction.
In the keyboard instrument, a plurality of openings are formed in the roof plate, and the plurality of diaphragms as the diaphragm are fixed to the roof plate in a state of being inserted into the plurality of openings, respectively. Is done.
Further, in the keyboard instrument, each of the plurality of vibration generating portions corresponds to each of the plurality of vibration plates by an attachment member attached to the back surface of the roof plate across one corresponding one of the plurality of openings. Provided on one backside.
In the keyboard instrument, a plurality of thin portions as the diaphragm are formed on the roof plate.
Further, in the keyboard instrument, each of the plurality of vibration generating portions corresponds to the corresponding one of the plurality of thin portions by an attachment member that is attached to the back surface of the roof plate across the corresponding one of the plurality of thin portions. One is provided on the back surface.

Further, in the keyboard instrument, the instrument housing includes a keyboard lid that covers the keyboard, the keyboard lid is configured to open and close with the rear end as a rotation axis, and the exterior surface that the diaphragm forms a part of, This is the surface facing the performer when the keyboard lid is open.
In other words, since the sound is emitted from the diaphragm provided as part of the surface facing the performer (the back of the keyboard lid) when the keyboard lid is open, there is no need to emit sound via tone escape. Can be delivered to the player efficiently.
Moreover, there is no need to form a tone escape in the instrument housing.

In the keyboard instrument, the diaphragm has a thin exterior surface.
That is, since the diaphragm is formed by using a part of the exterior surface of the instrument housing, the boundary line between the diaphragm and the exterior surface of the instrument housing is not visible in appearance, and the existence of the diaphragm is not known at all. So, the appearance design of the instrument is not impaired at all.

In the keyboard instrument, an opening is formed on the exterior surface, and a diaphragm is provided to cover the opening.
Therefore, since the diaphragm can be formed of a material different from that of the exterior surface, the tone color can be changed by selecting the material.

The seventh feature of the keyboard instrument is that the exterior surface is made of wood, and the diaphragm is made of a material having higher acoustic impedance than wood.
Therefore, realistic sound can be emitted from the diaphragm.

In the keyboard musical instrument of the invention according to this application, the surface of the diaphragm is covered with a film having the same design as that of the exterior surface around the diaphragm.
Accordingly, since the appearance of the diaphragm is difficult to understand in appearance, the appearance design of the musical instrument is not impaired.

In the keyboard instrument, an attachment member is attached to the rear surface of the diaphragm across the diaphragm, and the vibration generating portion is attached to the attachment member.
Therefore, since the rigidity at the attachment portion of the vibration generating portion can be increased, the vibration generated by the vibration generating portion can be efficiently conducted to the diaphragm, so that a realistic sound can be emitted.

In the keyboard instrument, the diaphragm emits a high-frequency sound.
Therefore, it is possible to emit a high-frequency sound with a realistic spread without attaching a speaker that emits a high-frequency sound.

In keyboard instruments, realistic sounds can be emitted without compromising the overall design of the instrument.

1 is a perspective view of an electronic keyboard instrument according to a first embodiment. It is explanatory drawing which shows the attachment structure of the diaphragm attached to the electronic keyboard musical instrument shown in FIG. It is explanatory drawing which looked at the attachment structure of the diaphragm shown in FIG. 2 from the back surface. It is explanatory drawing which shows the main electrical structures of the electronic keyboard musical instrument shown in FIG. 1 with a block. It is a front view which shows the state which the electronic keyboard musical instrument which concerns on 2nd Embodiment opened the keyboard cover. (A) is a right view of the electronic keyboard musical instrument shown in FIG. 5, (b) is an enlarged view of the keyboard lid shown in (a). It is explanatory drawing which shows the structure of the diaphragm attached to the electronic keyboard musical instrument which concerns on 4th Embodiment. It is explanatory drawing which looked at the attachment structure of the diaphragm shown in FIG. 7 from the back surface.

<First Embodiment>
[Schematic configuration of electronic keyboard instrument 1]
A schematic configuration of an electronic keyboard instrument 1 as a keyboard instrument according to a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a perspective view of an electronic keyboard instrument 1 according to this embodiment. In the following description, the side closer to the player of the electronic keyboard instrument 1 is referred to as the front or the front, and the opposite direction is referred to as the rear or the rear. Further, the right side viewed from the player is the right side or the right side of the electronic keyboard instrument 1, and the left side viewed from the player is the left side or the left side of the electronic keyboard instrument 1.

The electronic keyboard instrument 1 includes a musical instrument housing 2, a keyboard 11 disposed at the front of the musical instrument housing 2, a soft pedal 13, a muffler pedal 14, a damper pedal 15, a right diaphragm 16, and a left vibration. The board 17 is provided with a right speaker 22 (FIG. 4) and a left speaker 23 (FIG. 4). The musical instrument housing 2 includes a right mother plate 3, a left mother plate 4, a right leg 5, a left leg 6, a shelf board 7, an upper front board 8, a lower front board 9, a roof board 10, A music stand 12 is provided. Of the right master plate 3, the left master plate 4, the right leg 5, the left leg 6, the shelf board 7, the upper front board 8, the lower front board 9, the roof board 10 and the music stand 12, the portion visible from the outside is the instrument housing. Constructs the exterior surface of the body. Hereinafter, when a matter common to the right diaphragm 16 and the left diaphragm 17 is described, it may be simply referred to as a diaphragm. Further, when a matter common to the right speaker 22 and the left speaker 23 is described, it may be simply referred to as a speaker. In the electronic keyboard instrument 1, the direction toward the right side as viewed from the player of the electronic keyboard instrument 1 is defined as the right direction, and the direction toward the left side is defined as the left direction. Further, the direction toward the front as viewed from the performer is defined as the front direction, and the direction toward the back is defined as the rear direction.

A shelf board 7 is attached between a right mother board 3 arranged on the right side of the musical instrument housing 2 and a left mother board 4 arranged on the left side, and a keyboard 11 is placed on the upper surface of the shelf board 7. Installed. A right leg 5 is formed at the front portion of the right mother plate 3, and a left leg 6 is formed at the front portion of the left mother plate 4. A lower front plate 9 is attached between the right main plate 3 and the left main plate 4 and on the rear surface of the bottom surface of the shelf plate 7. A soft pedal 13, a muffler pedal 14, and a damper pedal 15 are arranged at the lower part of the lower front plate 9 so as to protrude forward. An upper front plate 8 is attached between the right mother plate 3 and the left mother plate 4 and behind the keyboard 11. A front surface 8 a of the upper front plate 8, which is an exterior surface, faces a player who performs in front of the electronic keyboard instrument 1. A roof plate 10 is attached to the upper part of the upper front plate 8 and between the upper ends of the right main plate 3 and the left main plate 4. A music stand 12 is attached to the center of the roof plate 10. That is, the music stand 12 is attached to the upper surface 10a of the roof board 10 in the center in the left-right direction of the roof board 10 (key arrangement direction of the keyboard 11). In FIG. 1, the music stand 12 is in a folded state, but can be changed to a standing posture with the lower end as a rotation axis.
In the roof plate 10, a square right diaphragm 16 is provided on the right side of the music stand 12, and a square left diaphragm 17 is provided on the left side of the music stand 12. The right diaphragm 16 and the left diaphragm 17 are each provided as a part of the upper surface 10a of the roof plate 10 that is an exterior surface. That is, the music stand 12 is disposed at a position sandwiched between the right diaphragm 16 and the left diaphragm 17 in the left-right direction, and the music stand 12 is arranged on the roof in the left-right direction of the right diaphragm 16 and the left diaphragm 17. The plate 10 is disposed at a substantially central portion on the upper surface 10a. In other words, the right diaphragm 16 and the left diaphragm 17 are disposed on the upper surface 10a of the roof plate 10 at positions substantially the same distance on the right side and the left side from the music stand 12.

[Vibration mounting structure]
Here, the attachment structure of each

diaphragm

16 and 17 is demonstrated based on FIG. 2 and FIG.
2 is an explanatory view showing a mounting structure of a diaphragm attached to the electronic keyboard instrument 1 shown in FIG. 1, and FIG. 3 is an explanatory view of the mounting structure of the diaphragm shown in FIG. is there. Hereinafter, when the matters common to the right transducer 18 and the left transducer 19 (FIG. 4) are described, they may be simply referred to as a transducer.

As shown in FIG. 2, a rectangular opening 10b is formed through the left side of the upper surface 10a of the roof plate 10, which is the exterior surface, and between the opening 10b and the upper surface 10a, the left A step portion 10c for attaching the diaphragm 17 (FIG. 1) is formed. The step portion 10 c is formed at a step that matches the thickness of the left diaphragm 17. That is, the stepped portion 10c is a stepped portion whose bottom wall is formed at a position away from the upper surface 10a of the roof plate 10 by the thickness of the left diaphragm 17. The shape drawn by the boundary between the upper edge of the step 10c and the upper surface 10a of the roof plate 10 is a quadrangle that matches the shape of the left diaphragm 17, and the outer peripheral wall of the left diaphragm 17 is the inner peripheral wall of the step 10c. Is housed in. Screw insertion holes (not shown) for inserting the same countersunk screws 29 as the countersunk screws 29 to which the right diaphragm 16 is attached are formed in a plurality of locations such as the four corners of the left diaphragm 17. A recess (not shown) that matches the shape of the head of the countersunk screw 29 is formed around the upper edge of the screw insertion hole. In addition, a plurality of screw holes for screwing the countersunk screws 29 are formed in the bottom wall of the stepped portion 10c.

The left diaphragm 17 is attached to the step portion 10c so as to cover the opening portion 10b by screwing each flat head screw 29 inserted into each screw insertion hole into the screw hole of the bottom wall of the step portion 10c. The head of the countersunk screw 29 is accommodated in the recess and does not protrude from the upper surface of the left diaphragm 17. For this reason, the upper surface of the left diaphragm 17 attached to the step portion 10 c is flush with the upper surface 10 a of the roof plate 10. The upper surface of the left diaphragm 17 is covered with a film having the same design as the design (color, color, pattern, etc.) applied to the upper surface 10a of the roof panel 10, and the presence of the left diaphragm 17 is difficult to understand in appearance. Has been devised. The right diaphragm 16 is also attached to the right side of the roof board 10 by the same mounting structure as the left diaphragm 17, and the upper surface thereof is covered with the membrane of the above design. The film | membrane which coat | covers each

diaphragm

16 and 17 may be formed by coating, and may be formed by sticking resin-made films | membranes.

As shown in FIG. 3, on the right side (left side in FIG. 3) of the back surface 10 d of the roof plate 10, a metal mounting stay 20 is placed on the back surface 10 d of the roof plate 10 so as to straddle the back surface of the right diaphragm 16. The right transducer 18 is fixed to the upper surface of the mounting stay 20. That is, the mounting stay 20 is fixed to the back surface 10d of the roof board 10 so as to straddle the opening 10b of the roof board 10 in the left-right direction. A network circuit (not shown) for cutting a specific frequency band is electrically connected to the right transducer 18, and the network circuit is connected to an amplifier 26 (by a connection cable 21 attached to the back surface 10 d of the roof plate 10. 4). The right transducer 18 is an actuator that converts an electric signal supplied from the amplifier 26 into vibration, and includes a movable body that generates vibration. The right transducer 18 is fixed to the mounting stay 20 so that the head of the movable body that moves forward and backward strikes the back surface of the right diaphragm 16. The head of the movable body of the right transducer 18 is fixed to the mounting stay so as to hit the back surface of the central portion of the right vibrating body 16 (the central portion of the right vibrating body 16 in the left-right direction and the front-rear direction). The right transducer 18 moves the movable body forward and backward according to the electric signal supplied from the amplifier 26 (FIG. 4), and vibrates the right diaphragm 16. Thereby, a sound corresponding to the electric signal is emitted from the right diaphragm 16. On the back surface of the left diaphragm 17, the left transducer 19 (FIG. 4) has the same mounting structure as the right transducer 18 (the head of the movable body of the left transducer 19 by the mounting stay 20 fixed to the back surface 10d of the roof plate 10). The left diaphragm 17 is vibrated by the left transducer 19 and emits sound. Therefore, the right transducer 18 and the left transducer 19 are arranged at positions sandwiching the music stand 12 in the left-right direction. In other words, the right transducer 18 and the left lance reducer 19 are arranged symmetrically with respect to the music stand 12 in the left-right direction.

In this embodiment, the musical instrument housing 2 is made of wood, and the right diaphragm 16 and the left diaphragm 17 are made of a material having a higher acoustic impedance than wood, for example, iron, and are formed in a quadrilateral shape. It is formed in a thin plate shape than the plate 10 and the shelf plate 7. Here, the acoustic impedance is a pressure necessary to vibrate air at a unit speed, that is, a resistance value related to sound, and an approximate value can be obtained by sound speed × material density. The higher the acoustic impedance, the more realistic high sound can be emitted by vibration. For example, the acoustic impedance of glass is larger than that of wood, and metal such as iron is larger than glass. For this reason, if the diaphragm is formed of a metal such as iron, brass, or duralumin as in this embodiment, a realistic high sound can be emitted from the diaphragm. Moreover, when forming a diaphragm with a metal, the plate | board thickness can be 1 mm, 0.5 mm, and 0.1 mm, for example. Further, the diaphragm may be configured by attaching a metal plate material to a high-strength material such as FRP (Fiber Reinforced Plastic).
The right transducer 18 and the left transducer 19 are voice coil type actuators including a magnet, a voice coil, and a movable body, and are also called vibrators. The cut-off frequencies of the right transducer 18 and the left transducer 19 are 6,500 Hz, respectively, and are set higher than the fundamental key tone of the acoustic piano, 4,000 Hz. Can give a sense of transparency and air. The right speaker 22 and the left speaker 23 (FIG. 4) are full-range speakers, and the

diaphragms

16 and 17 serve as tweeters that emit high-frequency sounds.

[Electrical configuration of electronic keyboard instrument]
Next, the main electrical configuration of the electronic keyboard instrument 1 will be described with reference to FIG.

The electronic keyboard instrument 1 includes a sensor 27, a sound source data storage unit 24, an electric signal generation unit 25, an amplifier 26, a right speaker 22, a left speaker 23, a right transducer 18, and a left transducer 19. The sensor 27 detects an operation of the keyboard 11 and outputs a detection signal to the electric signal generator 25. The sound source data storage unit 24 is sound source data for emitting sounds corresponding to each key of the keyboard 11, and is a sound source obtained by sampling the sound actually emitted when each key of the acoustic piano is operated. Data is stored in a readable manner. The electric signal generation unit 25 reads sound source data corresponding to the detection signal output from the sensor 27 from the sound source data storage unit 24, converts the read sound source data into analog electric signals of two channels on the left and right sides, and supplies them to the amplifier 26. Output. The amplifier 26 amplifies the electrical signal output from the electrical signal generator 25, outputs the amplified right channel electrical signal to the right speaker 22 and the right transducer 18, and outputs the amplified left channel electrical signal to the left speaker 23. And output to the left transducer 19.

The right transducer 18 generates vibration in accordance with the right channel electrical signal output from the amplifier 26, transmits the vibration to the right diaphragm 16 from the back surface, and the right diaphragm 16 vibrates and emits sound. . The left transducer 19 generates vibration in accordance with the left channel electrical signal output from the amplifier 26, transmits the vibration to the left diaphragm 17 from the back surface, and the left diaphragm 17 vibrates and emits sound. .
That is, the

transducers

18 and 19 generate vibrations corresponding to the electric signals supplied from the amplifier 26 and transmit the vibrations to the

diaphragms

16 and 17 from the back surface. And each

diaphragm

16 and 17 vibrates, respectively, and the sound according to the said electric signal is each emitted.

[Effect of the first embodiment]
(1) If the electronic keyboard instrument 1 of the first embodiment described above is implemented, the

diaphragms

16 and 17 that emit sound according to the electric signal constitute the exterior surface of the instrument housing 2. 10 is provided as a part of the upper surface 10a of the ten, it is possible to emit a realistic high-frequency sound without impairing the design of the entire instrument.
In addition, since the

diaphragms

16 and 17 vibrate on the surface, the sound attenuation according to the distance from the sound source is less than that of the point sound source, so that the high-frequency sound can be efficiently delivered to the player and audience. .

(2) Moreover, since the sound is emitted from the upper surface 10a of the roof plate 10 which is the exterior surface, it is possible to emit a wide range of high sound.
In addition, there is no need to form a tone escape in the instrument housing 2. (3) Furthermore, since the

diaphragms

16 and 17 can be made of a material different from that of the instrument housing 2, the tone color can be changed by selecting the material.

(4) Furthermore, the exterior surface of the musical instrument housing 2 is made of wood, and the

diaphragms

16 and 17 are made of a material having an acoustic impedance higher than that of wood. It is possible to emit a sound in the high range. (5) Further, since the surfaces of the

diaphragms

16 and 17 are covered with a film having the same design as the surroundings thereof, the presence of the

diaphragms

16 and 17 is difficult to understand, so that the design of the musical instrument is not impaired.

(6) Furthermore, metal mounting stays 20 are fixed to the back surfaces of the

diaphragms

16 and 17 so as to straddle the diaphragms, and the

transducers

18 and 19 are respectively attached to the mounting stays 20. ,
Therefore, since the rigidity at the mounting portion of each

transducer

18, 19 can be increased, the vibration generated by each

transducer

18, 19 can be efficiently conducted to each

diaphragm

16, 17, so that a realistic sound is released. Can sound. (7) Furthermore, since each

diaphragm

16 and 17 can emit a high-frequency sound, a high-frequency range with a realistic spread can be obtained without an external speaker that emits a high-frequency sound. Can be released. (8) As described above, if the electronic keyboard instrument 1 of the first embodiment is implemented, a realistic sound can be emitted without deteriorating the design of the entire instrument.

Second Embodiment
Next, a second embodiment of the present invention will be described with reference to FIGS.
As shown by a broken line in FIG. 1, the electronic keyboard musical instrument 1 according to this embodiment is an exterior surface of the musical instrument housing 2, which is an outer surface of an upper front plate 8 that is disposed so as to face the performer. As a part, a right diaphragm 16a and a left diaphragm 17a are provided. Since the upper front plate 8 has a shorter vertical length than the roof plate 10, the

diaphragms

16a and 17a are formed in a rectangular shape that is shorter than the

diaphragms

16 and 17 of the first embodiment. Yes. The attachment structure of each

diaphragm

16a, 17a is the same as the attachment structure in the first embodiment. The main electrical configuration is the same as that of the first embodiment.

[Effects of Second Embodiment]
As described above, when the electronic keyboard instrument 1 of the second embodiment is implemented, each vibration provided as a part of the front surface 8a of the upper front plate 8 arranged to face the performer, which is an exterior surface. Since the sound is emitted from the

plates

16a and 17a, it is not necessary to emit the sound via the tone escape, so that the sound can be efficiently delivered to the player and the audience.
In addition, there is no need to form a tone escape in the instrument housing 2.

<Third Embodiment>
Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 5 is a front view showing a state in which the electronic keyboard instrument 1 according to this embodiment has opened the keyboard lid 28. 6A is a right side view of the electronic keyboard instrument 1 shown in FIG. 5, and FIG. 6B is an enlarged view of the keyboard lid 28 shown in FIG.

The electronic keyboard instrument 1 according to this embodiment is characterized in that the

diaphragms

16 b and 17 b are provided on the keyboard lid 28.
As shown in FIG. 5, the musical instrument housing 2 includes a keyboard lid 28 that covers the keyboard 11. The keyboard lid 28 has a structure that opens and closes with the rear end as a rotation axis. When the keyboard lid 28 is opened, the back surface 28a is exposed and is opposed to the player. A right diaphragm 16b is provided on the right side of the back surface 28a of the keyboard lid 28, which is the exterior surface, and a left diaphragm 17b is provided on the left side as a part of the back surface 28a. As shown in FIG. 6B, a right transducer 18b is attached to the back surface of the right diaphragm 16b via an attachment stay 20b. A network circuit (not shown) is electrically connected to the right transducer 18b, and the network circuit is electrically connected to the amplifier 26 (FIG. 4) by a connection cable 21b. Although not shown, a left transducer is attached to the back surface of the left diaphragm 17b via an attachment stay. A network circuit (not shown) is electrically connected to the left transducer, and the network circuit is electrically connected to the amplifier 26 (FIG. 4) by a connection cable. The mounting structure and main electrical configuration of each transducer 18b, 19b is the same as the mounting structure of the first embodiment.

[Effect of the third embodiment]
As described above, when the electronic keyboard instrument 1 of the third embodiment is implemented, sound is emitted from the

diaphragms

16b and 17b provided as a part of the back surface 28a facing the player when the keyboard lid 28 is opened. Therefore, since it is not necessary to emit sound via tone escape, the sound can be efficiently delivered to the player and audience.
In addition, there is no need to form a tone escape in the instrument housing 2.

<Fourth Embodiment and Other Embodiments>
(1) Of the exposed upper surface 10a of the roof plate 10, areas corresponding to the

diaphragms

16 and 17 of the first embodiment are formed thin, and the areas formed in the thin wall are used as diaphragms. You can also. A fourth embodiment as this embodiment is shown in FIGS. FIG. 7 is a view corresponding to FIG. 2 of the first embodiment, and is a view of the roof plate 10 as viewed from above. FIG. 8 is a view corresponding to FIG. 3 of the second embodiment, and is a view of the roof plate 10 shown in FIG. 7 as viewed from the back surface (lower side).
In FIG. 7, the roof plate 10 includes thin portions 10 e on both sides of the music stand 12 in the left-right direction. The top surface 10 a of the roof plate 10 is a flat surface, and the thin portion 10 e is provided on the roof plate 10 by forming a recess on the back surface 10 d side of the roof plate 10. That is, the thickness of the thin portion 10e of the roof plate 10 is smaller by the depth of the recess formed in the back surface 10d than the thickness of the roof plate 10 where the thin portion 10e is not formed. In the present embodiment, the roof plate 10 can be configured as follows. Two plate members, an upper plate member 10f and a lower plate member 10g are prepared, and the upper plate member 10f and the lower plate member 10g in which a through hole is formed are bonded together to form one roof plate 10. The thin portion 10e is a portion corresponding to the through hole of the lower plate member 10g of the upper plate member 10f.
As shown in FIG. 7, the two thin portions 10 e formed in this way are arranged at positions that sandwich the music stand 12 in the left-right direction. As shown in FIG. 8, the mounting stay 20 is attached to the back surface of the lower plate member 10g so as to straddle the through hole of the lower plate member 10g in the left-right direction. The transducer 18 supported by the mounting stay 20 enters the thin-walled portion 10e, that is, the through hole of the lower plate member 10g, and is in contact with the back surface of the upper side 10f. Also in this embodiment, there exists an effect similar to 1st Embodiment. Furthermore, the roof board 10 of the present embodiment has a flat upper surface 10a, and the boundary between the thin portion 10e of the roof board 10 and the other portions cannot be seen on the upper surface 10a. There is no. As described above, in the present embodiment, the roof plate 10 is configured by the upper plate member 10f and the lower plate member 10g. However, the roof plate 10 may be configured by a single plate member. In this case, two recesses are formed on the back surface of the roof plate 10 by means of cutting or the like, and the portion of the roof plate 10 where the thickness is reduced by the depth of the two recesses is defined as a thin wall portion. It ’s fine.
Moreover, the area | region corresponding to each

diaphragm

16a, 17a of 2nd Embodiment is each formed thinly among the front surface 8a which the upper front board 8 exposed, and each area | region formed in the thin part is each used as a diaphragm. You can also. That is, a part of the exterior surface of the musical instrument housing 2 can be formed thin and used as a diaphragm.
In each of the above-described embodiments, the present invention is applied to an electronic keyboard instrument. However, the present invention is not limited to this configuration, and the present invention may be applied to an acoustic keyboard instrument. For example, when the present invention is applied to a grand piano, it is possible to configure lamp stands on both sides of a music stand as a diaphragm that is part of the exterior surface. Moreover, when applying this invention to an upright piano, it is possible to comprise a part of roof board as a diaphragm of a part of exterior surface. In addition, some acoustic keyboard instruments generate sound by vibrating the sound board not only with the vibration of the string but also with the transducer. The present invention is applied to this, and in addition to the sound board, a part of the exterior surface is applied. You may comprise as a keyboard musical instrument to vibrate as a diaphragm.
If the diaphragm is formed using a part of the exterior surface of the instrument housing 2 as described above, the boundary line between each diaphragm and the instrument housing 2 cannot be seen, so the existence of the diaphragm is completely unknown. Because it is not, the design of the instrument is not impaired at all.

(2) In the first embodiment, the upper surface 10a of the roof plate 10 and the upper surfaces of the

diaphragms

16 and 17 are covered with one film so that the boundary line between the

diaphragms

16 and 17 and the upper surface 10a does not appear. It can also be configured. In the second embodiment, the front surface 8a of the upper front plate 8 and the front surfaces of the

diaphragms

16a and 17a are covered with one film so that the boundary line between the

diaphragms

16a and 17a and the front surface 8a does not appear. It can also be configured.
Thus, if each

diaphragm

16, 17, 16a, 17a and its periphery are covered with one film, the boundary line between each

diaphragm

16, 17, 16a, 17a and the instrument housing 2 is hidden, Since the existence of the diaphragm is completely unknown, the design of the instrument is not impaired.

(3) Each diaphragm can be integrally provided on the front surface of the lower front plate 9 (FIG. 1).
Alternatively, the music stand 12 can be formed horizontally long, each diaphragm can be integrally provided on the front surface of the music stand 12, and each transducer can be provided inside the music stand 12. If this structure is implemented, sound can be emitted from each diaphragm in a state where the music stand is erected, so that realistic sounds can be emitted without impairing the overall design of the instrument. The music stand 12 is preferably sized so that the musical score does not interfere with sound emission, and each diaphragm is disposed.

(4) Each diaphragm can also be configured to emit a mid-high range. Further, two diaphragms for high sound range and medium sound range can be provided. Moreover, each diaphragm can also be formed in shapes, such as ellipse other than a rectangle, or a circle. Furthermore, each diaphragm can be formed of resin. Furthermore, in 1st and 2nd embodiment, each diaphragm can also be adhere | attached and attached to the step part 10c with an adhesive agent. Furthermore, without forming the stepped portion 10c, the diaphragm can be formed to have substantially the same size as the opening 10b, and the diaphragm can be fitted into the opening 10b. Furthermore, it is also possible to form convex portions at a plurality of locations on the inner wall of the opening 10b, form concave portions corresponding to the convex portions on the diaphragm, and fit each concave portion of the diaphragm to each convex portion of the opening portion. . In addition, a recessed part may be formed in the opening part 10b, and a convex part may be formed in a diaphragm.

[Correspondence with Claims]
The sound source data storage unit 24 and the electric signal generation unit 25 correspond to the sound source, and the

transducers

18, 19, 18b correspond to the vibration generation unit. The mounting stay corresponds to the mounting member.

DESCRIPTION OF SYMBOLS 1 Electronic keyboard musical instrument 2 Musical instrument housing 8 Upper front board 8a Front surface 10 Roof board 10a Upper surface 11

Keyboard

16, 16a,

16b Right diaphragm

17, 17a,

17b Left diaphragm

18, 18b Right transducer 19

Left transducer

20, 20b Mounting stay 24 sound source data storage unit 25 electric signal generation unit

Claims

Instrument housing,
A keyboard arranged at the front of the instrument housing;
A sound source that supplies electrical signals in response to the operation of the keyboard;
A diaphragm constituting a part of the exterior surface of the instrument housing;
At least one which is provided on the back surface of the diaphragm, generates vibration according to the electrical signal supplied from the sound source, and transmits the vibration to the diaphragm from the back surface of the exterior surface of the diaphragm. A keyboard instrument comprising two vibration generators.
The keyboard instrument according to claim 1, wherein the exterior surface is an upper surface of a roof plate in the instrument casing.
The keyboard instrument according to claim 1, wherein the exterior surface is a surface of the instrument housing that faces the performer.
A plurality of vibration generators as the at least one vibration generator provided on the back surface of the diaphragm,
4. The keyboard instrument according to claim 1, wherein the plurality of vibration generating units are arranged in a first direction in which a plurality of keys of the keyboard are arranged. 5.
A music stand is attached to the upper surface of the diaphragm,
The keyboard instrument according to claim 4, wherein the plurality of vibration generating units are respectively arranged at positions sandwiching the music stand in the first direction.
In the roof plate, a plurality of openings are formed,
The keyboard instrument according to claim 4 or 5, wherein the plurality of diaphragms as the diaphragm are respectively fixed to the roof plate in a state of being inserted into the plurality of openings.
Each of the plurality of vibration generating portions is provided on one corresponding back surface of the plurality of vibration plates by an attachment member attached to the back surface of the roof plate across one corresponding one of the plurality of openings. The keyboard instrument according to 6.
The keyboard instrument according to claim 4 or 5, wherein a plurality of thin portions as the diaphragm are formed on the roof plate.
Each of the plurality of vibration generating portions is provided on the corresponding one back surface of the plurality of thin wall portions by an attachment member that is attached to the back surface of the roof plate across the corresponding one of the plurality of thin wall portions. Item 10. The keyboard instrument according to Item 8.
The instrument housing includes a keyboard lid that covers the keyboard,
The keyboard lid is structured to open and close with the rear end as a pivot axis,
The keyboard instrument according to claim 1, wherein the exterior surface is a surface that faces a performer in a state where the keyboard cover is opened.
The keyboard instrument according to any one of claims 1 to 10, wherein the diaphragm has a thin outer surface.
An opening is formed in the exterior surface,
The keyboard instrument according to claim 1, wherein the diaphragm is provided so as to cover the opening.
The exterior surface is made of wood,
The keyboard instrument according to claim 1, wherein the diaphragm is formed of a material having an acoustic impedance higher than that of the wood.
The keyboard instrument according to any one of claims 1 to 13, wherein a surface of the diaphragm is covered with a film having the same design as the surrounding exterior surface.
An attachment member is attached to the back surface of the exterior surface across the diaphragm,
The keyboard instrument according to claim 1, wherein the vibration generating unit is attached to the attachment member.
The keyboard instrument according to any one of claims 1 to 15, wherein the diaphragm emits a high-frequency range sound.