WO2017057667A1 - Electronic musical instrument - Google Patents

Abstract

This electronic musical instrument, which is provided with a keyboard comprising a plurality of keys and creates musical sounds by pressing the plurality of keys, includes at least one speaker device. The speaker device includes: a cabinet having a vertical length that is shorter than both the horizontal length and the longitudinal length thereof, and provided with a sound passage on the interior for propagating aerial vibration; and a speaker unit equipped in the cabinet in such a way that the front side of the speaker unit is directed outside the cabinet while the rear side is directed to a space provided in front of the sound passage inside the cabinet. The speaker device is a back-loaded horn speaker device that introduces the aerial vibration created by the speaker unit into the sound passage, and introduces the aerial vibration that propagates through the sound passage to the outside. The speaker device is arranged parallel to the upper surface of the keyboard so that the horizontal direction thereof is the alignment direction of the plurality of keys.

Description

Electronic musical instruments

The present invention relates to an electronic musical instrument in which a back load horn type speaker device is assembled.

Conventionally, as shown in the following Patent Document 1, an electronic musical instrument in which a back load horn type speaker device is assembled is known. In this electronic musical instrument, the speaker unit is assembled to the electronic musical instrument main body located above with the front side facing upward and the back side facing downward. A horn portion extending downward from above is provided in the side plate that supports the electronic musical instrument main body, and air vibrations from the speaker unit are propagated downward through the horn portion so as to generate a musical sound from the lower end portion of the side plate. I have to.

Japanese Unexamined Patent Publication No. 2-29790

According to the above-described conventional electronic musical instrument, even if the speaker unit is small, it is possible to generate a sufficiently low sound, that is, to generate a good musical sound. However, the conventional back load horn type speaker device cannot be assembled to an electronic musical instrument having no side plate. Specifically, a backloaded horn type speaker device cannot be assembled to an electronic musical instrument with a thin thickness in the vertical direction, such as an electronic keyboard harmonica or a small electronic musical instrument having only one keyboard. In addition, since a small electronic musical instrument usually employs a small speaker device, it is not possible to generate good musical sounds.

The present invention has been made to address the above-described problems, and an object of the present invention is to generate a good musical tone using a backloaded horn type speaker device in an electronic musical instrument having a thin vertical thickness. is there.
In the description of each constituent element of the present invention below, the reference numerals of corresponding portions of the embodiment are shown in parentheses in order to facilitate understanding of the present invention. The present invention should not be construed as being limited to the configurations of the corresponding portions indicated by the reference numerals of the forms.

In order to achieve the above object, the present invention includes a keyboard (12, 42) composed of a plurality of keys, and an electronic musical instrument that generates a musical sound by pressing a plurality of keys has at least one speaker device. The speaker device has a cabinet (20, 50A, 50B) in which the length in the vertical direction is shorter than the length in the horizontal direction and the front-back direction and has a sound path for propagating air vibrations inside, and the front side is the outside of the cabinet. And a speaker unit (30, 60A, 60B) assembled to the cabinet with the back side facing the space provided inside the cabinet and in front of the sound path, and the speaker device is a speaker unit. This is a back-loaded horn type speaker device that guides air vibration caused by sound to the sound path and guides air vibration propagated through the sound path to the outside. Parallel, to provide an electronic musical instrument to which the lateral direction is arranged such that the array direction of the plurality of keys.

In this case, for example, the at least one speaker device is one speaker device, the length of the cabinet of the one speaker device in the left-right direction is larger than the length in the front-rear direction, and the one speaker device is in the left-right direction. Are preferably arranged in a direction in which a plurality of keys are arranged. The at least one speaker device may be two speaker devices, and the two speaker devices may be arranged to correspond to a right side portion and a left side portion of a keyboard. Further, the speaker unit may be assembled on the upper surface of the cabinet. Furthermore, the cabinet has, for example, a rectangular parallelepiped shape.

In the present invention configured as described above, the length in the vertical direction of the cabinet in which the speaker unit is assembled is made shorter than the length in the left-right direction and the front-rear direction, so that the backloaded horn type speaker device is parallel to the upper surface of the keyboard. It was made to arrange in. As a result, the backload horn type speaker device can also be assembled to an electronic musical instrument having a thin thickness in the vertical direction, such as an electronic keyboard harmonica, a small electronic musical instrument equipped with only one keyboard. As a result, an electronic musical instrument in which a backload horn type speaker device is assembled can be realized. The back load horn type speaker device can generate a good musical tone even in a small electronic musical instrument.

Another feature of the present invention is that the speaker device is arranged below the keyboard, and an electric circuit board provided with an electric switch for detecting the operation of pressing and releasing a plurality of keys is arranged between the keyboard and the speaker device. There is. According to this, the electric circuit board (18, 48) provided with the electric switch and the back load horn type speaker device can be accurately placed in a small electronic musical instrument without increasing the longitudinal length of the electronic musical instrument. Can be incorporated.

1 is a schematic perspective view of an electronic keyboard harmonica according to a first embodiment of the present invention. FIG. 2 is a schematic layout diagram of an operator, a keyboard, an electric circuit board, and a backload horn type speaker device in the electronic keyboard harmonica of FIG. 1. FIG. 3 is a top view of the speaker device of FIG. 2. It is a right view of the speaker apparatus of FIG. It is the cross-sectional view which crossed the speaker apparatus of FIG. 2 below the speaker unit. It is a schematic sectional drawing of a speaker unit. FIG. 3 is an equivalent diagram of the speaker device of FIG. 2. It is a schematic perspective view of the electronic keyboard musical instrument which concerns on 2nd Embodiment of this invention. FIG. 9 is a schematic layout diagram of an operator, a keyboard, an electric circuit board, and a back load horn type speaker device in the electronic keyboard instrument of FIG. 8. FIG. 10 is a top view of the left speaker device of FIG. 9. FIG. 10 is a transverse cross-sectional view of the left speaker device incorporated in the electronic keyboard instrument of FIG. 9 crossed below the speaker unit. It is a schematic perspective view of the electronic keyboard musical instrument which concerns on the modification of 2nd Embodiment.

a. First Embodiment Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic perspective view of the electronic keyboard harmonica according to the first embodiment of the present invention. FIG. 2 is a schematic layout diagram of each component in the electronic keyboard harmonica.

In the following description of the electronic keyboard harmonica and the electronic keyboard musical instrument according to the second embodiment to be described later and various components included in the electronic keyboard harmonica, the horizontal direction, the front-rear direction, and the vertical direction are defined as follows. It is assumed that the electronic keyboard harmonica and the electronic keyboard musical instrument are placed on the table with the keyboards 12 and 42 facing upward, and the performer is positioned and played in front of the keyboards 12 and 42. The electronic keyboard harmonica also has the above-described performance state when a tube is connected to the outlet 14 described later and the performer blows in from the other end of the tube. When viewed from the performer, the left side (left side in FIGS. 1 and 8) is the left side, and the right side (right side in FIGS. 1 and 8) is the right side. The side closer to the performer (lower left side in FIGS. 1 and 8) is the front side, and the far side (upper right side in FIGS. 1 and 8) is the rear side. The upper surface side on which the keyboards 12 and 42 are arranged is the upper side, and the opposite side (table upper side) is the lower side. The left, right, front, back, top and bottom expressions are examples in the performance state as described above, and when the performance state is different, especially when playing with the electronic keyboard harmonica by hand, Needless to say, the vertical positional relationship changes.

The electronic keyboard harmonica has a rectangular parallelepiped case 11. The case 11 has a length in the left-right direction that is considerably longer than the length in the front-rear direction and is formed in an elongated shape in the left-right direction, and the length in the vertical direction is shorter than the length in the front-rear direction. Thinly formed in the vertical direction. A keyboard 12 made up of a plurality of white keys and black keys arranged along the left-right direction is assembled to the upper surface of the case 11. Behind the keyboard 12 on the upper surface of the case 11, a plurality of operators 13 for designating musical tone elements such as timbre and volume are provided. On the left side surface of the case 11, there is provided an air outlet 14 for the performer to squeeze with his mouth and breathe in.

A circular through hole for generating a musical sound to the outside is provided in the upper left portion of the case 11, and the upper surface of the through hole is covered with a net 15. Instead of the net 15, a large number of small through holes may be provided in the upper left portion of the case 11. The right side surface of the case 11 is released to generate a musical sound to the outside, and a net 16 is provided on the right side surface portion. In this case, in place of the net 16, a large number of small through holes may be provided in the right side surface portion of the case 11, or the right side surface may be simply opened. Further, in the case 11, a conical wall 17 (see FIG. 5) that opens upward at the lower position of the net 15 and opens the upper end surface and the lower end surface for guiding the air vibration corresponding to the musical sound to the outside. 2).

In the case 11, as shown in the layout diagram of FIG. 2, a cabinet 20 is fixed on the bottom plate of the case 11. That is, the cabinet 20 is arranged in parallel to the upper surface of the keyboard 12 and below the keyboard 12. The cabinet 20 is assembled with a speaker unit 30 to constitute a back load horn type speaker device according to the present invention. An electric circuit board 18 is assembled in the case 11 between the keyboard 12 and the cabinet 20. The electric circuit board 18 is made of a resin or the like and has a rectangular shape that is long in the left-right direction and is formed in a flat plate shape. On the upper surface of the electric circuit board 18, a plurality of electric switches (not shown) for detecting a key pressing / releasing operation of the plurality of keys are arranged and fixed in the left-right direction below the plurality of keys, respectively. A musical tone signal generator for generating musical tone signals is fixed. The case 11 is also provided with an air pressure sensor (not shown) for detecting the air pressure (breath pressure) blown from the air outlet 14. The musical tone signal generator generates a musical tone signal having a pitch corresponding to the key detected by the plurality of electric switches at a volume corresponding to the air pressure detected by the air pressure sensor.

The cabinet 20 has a rectangular parallelepiped shape composed of an upper case 21 and a bottom plate 22 as shown in the top and right side views of the speaker device in FIGS. 3 and 4. In the cabinet 20, in the first embodiment, the length L1 in the front-rear direction is 60 mm, the length L2 in the left-right direction is 360 mm, and the length L3 in the vertical direction is 21 mm. That is, in the cabinet 20, the length in the left-right direction is longer than the length in the front-rear direction, the length in the vertical direction is shorter than the length in the front-rear direction, and is relatively thin in the vertical direction.

The upper case 21 is integrally formed of resin, is formed in a flat plate shape and a rectangular shape, and has an upper wall 21a, a front wall 21b, a rear wall 21c, and a left wall 21d that are orthogonal to each other. The bottom plate 22 is formed of a resin into a flat plate shape and a rectangle having the same shape as the upper wall 21a of the upper case 21. The bottom plate 22 is brought into close contact with the lower surface of the front wall 21b, the rear wall 21c, the left wall 21d and the partition plates 21e1 to 21e8 described later on the upper surface of the bottom plate 22 by an adhesive. It is fixed. Accordingly, a rectangular parallelepiped space is formed in the cabinet 20 by opening only the right side to the outside. The opened opening on the right side faces the net 16 provided on the right side surface of the case 11.

In the upper case 21, flat and rectangular partition plates 21e1 to 21e8 are integrally formed with the upper case 21, as shown in the cross-sectional view of FIG. The partition plates 21e1 and 21e2 extend in a direction perpendicular to both inner surfaces of the upper wall 21a and the front wall 21b, their lower end surfaces are positioned on the upper surface of the bottom plate 22, and their rear end surfaces are rear wall 21c. It is located in front of. The partition plate 21e2 is located on the right side of the partition plate 21e1.

The partition plates 21e3 to 21e5 extend in a direction perpendicular to both inner surfaces of the upper wall 21a and the rear wall 21c, their lower end surfaces are positioned on the upper surface of the bottom plate 22, and their front end surfaces are the front walls 21b. It is located behind. The partition plate 21e3 is located in the middle in the left-right direction between the left wall 21d and the partition plate 21e1, the partition plate 21e4 is located in the middle in the left-right direction between the partition plate 21e1 and the partition plate 21e2, and the partition plate 21e5 is located between the partition plate 21e2 and the bottom plate 22. Located in the middle of the right and left direction.

The partition plate 21e6 extends from the inner surface of the upper wall 21a in a direction perpendicular to the inner wall, and extends from the inner surface of the left wall 21d to the right and slightly tilted rightward forward. It is located on the top surface. The partition plate 21e6 is located behind the front end surface of the partition plate 21e3, and the right end surface thereof is located to the left of the partition plate 21e3.

The partition plate 21e7 extends in a direction perpendicular to the inner side surface of the upper wall 21a, and extends from the front end surface of the partition plate 21e3 in the left-right direction with the right side slightly tilted rearward. It is located on the top surface. The left side portion of the partition plate 21e7 from the partition plate 21e3 is located in the middle of the front wall 21b and the partition plate 21e6 in the front-rear direction, and the left end surface thereof is located to the right of the left wall 21d. The right side portion of the partition plate 21e7 from the partition plate 21e3 is located behind the front wall 21b, and the right end surface thereof is located to the left of the partition plate 21e1.

The partition plate 21e8 extends from the inner surface of the upper wall 21a in a right angle direction, and extends from the rear end surface of the partition plate 21e1 by tilting the left side backward in the left direction. It is located on the top surface. The partition plate 21e8 is located in the middle of the partition plate 21e7 and the rear wall 21c in the front-rear direction, and the left end surface thereof is located to the right of the partition plate 21e3.

By such partition plates 21e1 to 21e8, a position between the right end surface of the partition plate 21e6 and the left side surface of the partition plate 21e3 is provided between the upper wall 21a and the bottom plate 22 as indicated by an arrow in FIG. To the right end surface of the front wall 21b and the rear wall 21c is formed. This air passage is an air passage for propagating air vibrations by the speaker unit 30, and this air passage is referred to as a sound path S1 in this specification. Since the cabinet 20 is formed in a long shape in the arrangement direction of the plurality of keys on the keyboard 12, the sound path S1 has the arrangement direction of the plurality of keys as the longitudinal direction. The total length of the sound path S1 is 90 cm in the first embodiment. The position between the right end surface of the partition plate 21e6 and the left side surface of the partition plate 21e3 is the entrance of the sound path S1, and the positions of the right end surfaces of the front wall 21b and the rear wall 21c are the exit of the sound path S1.

Further, in front of the entrance of the sound path S1, an area surrounded by the rear wall 21c, the left wall 21d and the partition plates 21e3 and 21e6 (more precisely, the rear wall 21c, the left wall 21d, the partition plate 21e3, and the partition plate) A substantially square space is formed in a region surrounded by a plane extending 21e6 to the partition plate 21e3. This space is referred to as an air chamber S2 in this specification. The volume of the air chamber S2 is 22 cm ³ in the first embodiment. And the horn part of the speaker unit 30 is formed in the cabinet 20 by this air chamber S2 and the said sound path S1. With such a horn portion, the vertical air vibration by the speaker unit 30 is bent by 90 degrees in the air chamber S2 to become horizontal vibration, and the air vibration is a sound whose longitudinal direction is the arrangement direction of a plurality of keys on the keyboard 12. Propagate in the direction of arrangement of a plurality of keys via the path S1.

A circular through hole 21a1 (see FIG. 6) is formed at the position of the upper wall 21a facing the air chamber S2, that is, at the left end position of the upper wall 21a. The speaker unit 30 is assembled to the portion of the upper wall 21a where the through hole 21a1 is located. Moreover, the upper surface of this through-hole 21a1 and the speaker unit 30 is opposed to the opening lower end surface of the conical wall 17 provided in the case 11 (see FIG. 2). The speaker unit 30 includes a chassis 31, a yoke 32, a magnet 33, a bobbin 34, a coil 35, and a cone 36 as shown in the enlarged vertical sectional view of FIG. 6.

The chassis 31 includes an annular bottom surface portion 31a, a cylindrical portion 31b protruding upward from an outer peripheral end portion of the bottom surface portion 31a, an annular portion 31c provided above the cylindrical portion 31b and formed annularly, and a cylinder. A plurality of long connecting portions 31d that connect the portion 31b and the annular portion 31c are provided. The plurality of connecting portions 31d extend obliquely upward from a plurality of circumferential positions at the upper end of the cylindrical portion 31b, and are respectively connected to a plurality of circumferential positions on the inner peripheral surface of the annular portion 31c. ing. A space is provided between the plurality of connecting portions 31d, and the back side of the cone 36 is opened to the outside.

The yoke 32 has a disk portion 32a formed in a disk shape and a columnar protrusion portion 32b protruding upward at the center position of the disk portion 32a. The yoke 32 is fixed to the upper surface of the bottom surface portion 31a of the chassis 31 at the lower surface of the disk portion 32a, and the protruding portion 32b protrudes upward. The magnet 33 is formed in an annular shape having a predetermined thickness, and is magnetized into an N pole and an S pole in the vertical direction. The magnet 33 is fixed to the upper surface of the disk portion 32a of the yoke 32 at the lower surface, the outer peripheral surface is brought into contact with the inner peripheral surface of the cylindrical portion 31b of the chassis 31, and the protruding portion 32b of the yoke 32 is inserted into the central through hole. Is penetrated. The magnet 33 is a neodymium magnet having a high magnetic flux density and a very strong magnetic force. This magnetic flux density is 1.9 N / A in the first embodiment.

The bobbin 34 is formed in a cylindrical shape, the lower end surface thereof is opened, and the protruding portion 32b of the yoke 32 is inserted into the bobbin 34. The upper end surface of the bobbin 34 is closed by the upper surface wall 34a. A coil 35 is wound on the lower outer peripheral surface of the bobbin 34. A conductive wire (not shown) is connected to the coil 35 so that a musical tone signal (electrical signal) is supplied from a musical tone signal generator provided on the electric circuit board 18 described above. Further, an annularly formed damper 37 is fixed to the outer peripheral surface of the bobbin 34 on the inner peripheral surface thereof. The damper 37 is fixed to the inner peripheral surface of the upper end portion of the cylindrical portion 31b of the chassis 31 at the outer peripheral surface thereof. The damper 37 is made of an elastic film-like elastic member, is formed by bending up and down alternately like a wave in the radial direction, and allows the bobbin 34 to be displaced in the vertical direction with respect to the chassis 31. . Therefore, the bobbin 34 and the coil 35 are supported by the chassis 31 and the yoke 32 via the damper 37 so as to be displaceable in the vertical direction. The strength of the damper 37 is 1.16 N / mm in the first embodiment.

The cone 36 is a thin plate-like member that is elastically deformed and formed in a conical shape. The cone 36 extends from the circular inner peripheral surface portion toward the outer peripheral surface portion with the outer side inclined upward. The inner peripheral end portion of the cone 36 is fixed on the outer peripheral surface of the upper end portion of the bobbin 34, and the outer peripheral end portion of the cone 36 is fixed on the inner peripheral surface of the annular portion 31 c of the chassis 31. Near the inner peripheral end portion of the cone 36, an outer peripheral end portion of a disc-shaped center cap 38 having a spherical surface protruding upward is fixed, and the upper portion of the upper surface wall 34a of the bobbin 34 is closed. In the first embodiment, the cone 36 has a weight of 0.4 g, and the cone 36 has a diameter of 1.9 cm.

The speaker unit 30 configured in this manner is inserted from above into a circular through hole 21a1 provided in the upper wall 21a of the upper case 21 with the front side of the cone 36 (upper side in FIG. 6) facing upward. . Then, the lower surface of the annular portion 31c of the chassis 31 is brought into close contact with the upper surface of the upper wall 21a outside the through hole 21a1, and the annular portion 31c is tightly fixed to the upper surface of the upper wall 21a with screws or an adhesive. Thereby, the speaker unit 30 is fixed to the upper wall 21a of the cabinet 20.

In the speaker device configured as described above, when an electric signal which is a musical tone signal from the musical tone signal generator is supplied to the coil 35, the bobbin 34 is connected to the chassis 31 and the yoke 32, that is, to the cabinet 20, as shown in FIG. And it vibrates in the up-down direction shown in FIG. Due to the vertical vibration of the bobbin 34, the cone 36 also vibrates in the vertical direction, and the cone 36 vibrates the air. The air vibration on the front side of the speaker unit 30 due to the vibration of the cone 36 is propagated to the upper outside of the cabinet 20, and a musical sound due to the air vibration is generated upward from the upper side of the cabinet 20. The musical sound passes through the inside of the conical wall 17 provided in the case 11 and is generated as a musical sound by the electronic keyboard harmonica from above the case 11 through the net 15.

On the other hand, the air vibration on the back side of the speaker unit 30 due to the vibration of the cone 36 is bent 90 degrees in the air chamber S2 and enters the sound path S1 from the entrance of the sound path S1, and the arrangement direction of a plurality of keys on the keyboard 12 is elongated. Propagating along the direction of the sound path S1, is propagated to the exit of the sound path S1, that is, to the outside of the right side of the cabinet 20, and a musical sound due to air vibration is generated from the right side of the cabinet 20 toward the right side. And the state of the air vibration which propagates the sound path S1 widened toward the exit from the entrance is shown in FIG. 7 as an equivalent diagram of the speaker device. The musical sound generated from the right side of the cabinet 20 is sounded to the outside as a musical sound by the electronic keyboard harmonica from the right side of the case 11 through the net 16 provided on the right side surface of the case 11.

In the electronic keyboard harmonica configured as described above, the length of the cabinet 20 in which the speaker unit 30 is assembled is made shorter in the vertical direction than in the horizontal direction and the length in the front-rear direction, and the back horn type speaker device is used as the keyboard 12. It was made to arrange below. As a result, the backload horn type speaker device can be assembled even in an electronic keyboard harmonica having a small thickness in the vertical direction, that is, in a direction perpendicular to the keyboard 12. As a result, it is possible to realize an electronic keyboard harmonica in which a back load horn type speaker device is assembled, and it is possible to generate a good musical sound by the back load horn type speaker device. In the electronic keyboard harmonica, the cabinet 20 with the speaker unit 30 assembled is disposed below the keyboard 12, and the electric circuit board 18 is disposed between the keyboard 12 and the cabinet 20. As a result, the electric circuit board 18 and the cabinet 20 can be accurately incorporated in the electronic keyboard harmonica.

In the above speaker device, since the neodymium magnet having a high magnetic flux density and a very strong magnetic force is used as the magnet 33, the diameter (outer diameter) of the cone 36 can be reduced (in this first embodiment). 1.9 cm), and the speaker unit 30 can be extremely small and light. Since the speaker unit 30 is extremely small and light, especially the cone 36, the high-frequency phase characteristics are improved, and a sharp sound can be obtained.

Further, the entire length of the sound path S1 is shortened (90 cm in the first embodiment), the volume of the air chamber S2 is reduced (22 cm ³ in the first embodiment), and the cabinet 20 is reduced. Thereby, a speaker apparatus can be reduced in size extremely. Further, as described above, the air chamber S2 is made small to output a sound from a low range to a mid range, that is, from 100 Hz to 1 KHz. Thereby, the dynamic range of the sound can be widened and the volume can be increased. For example, a volume of 6 dB or more can be obtained.

b. Second Embodiment Next, a second embodiment in which the present invention is applied to a small-sized electronic keyboard instrument having no air outlet such as the electronic keyboard harmonica of the first embodiment will be described with reference to the drawings. FIG. 8 is a schematic perspective view of the small electronic keyboard instrument. FIG. 9 is a schematic layout diagram of components in the electronic keyboard instrument. In the description of the second embodiment, the left-right direction, the front-rear direction, and the up-down direction are as defined above.

The electronic keyboard instrument has a rectangular parallelepiped case 41. As in the first embodiment, the case 41 is formed in a long shape in the left-right direction with the length in the left-right direction being considerably longer than the length in the front-rear direction, and the length in the vertical direction is set in the front-rear direction. It is shorter than the length of and is thin in the vertical direction. However, the length of the case 41 in the front-rear direction is slightly longer than the length of the case 11 in the first embodiment. A keyboard 42 composed of a plurality of white keys and black keys arranged along the left-right direction is assembled to the upper surface of the case 41. A plurality of operators 43 for designating musical tone elements such as timbre and volume are provided behind the keyboard 42 on the upper surface of the case 41.

The left side portion and the right side portion of the upper surface of the case 11 are respectively provided with rectangular through holes for generating a musical sound to the outside, and the upper surfaces of these through holes are covered with nets 44 and 45, respectively. . In this case as well, a large number of small through holes may be provided in the left and right portions of the upper surface of the case 41 in place of the meshes 44 and 45, respectively. A rectangular opening is also provided in the lower part of the center position on the rear surface of the case 41 in order to generate a musical sound to the outside, and a net (not shown) is provided at the center position. In this case as well, in place of the net, a large number of small through holes may be provided in the lower central position of the rear surface of the case 41, or the lower central position of the rear surface may be simply opened. Further, in the case 41, the upper end surface and the lower end surface for guiding the air vibration corresponding to the musical sound to the outside are opened at the position below the nets 44 and 45 as in the case of the first embodiment. Conical walls 46 and 47 (see FIG. 9) that extend upward are provided respectively.

In the case 41, as shown in the layout diagram of FIG. 9, the cabinet 50 </ b> A is fixed to the left side portion on the bottom plate of the case 41, and the cabinet 50 </ b> B is fixed to the right side portion on the bottom plate of the case 41. That is, the cabinet 50 </ b> A is disposed in parallel with the upper surface of the keyboard 42 and below the keyboard 42. As in the case of the first embodiment, the cabinets 50A and 50B are assembled with the speaker units 60A and 60B, respectively, to constitute the backload horn type speaker device according to the present invention. In the case 41, an electric circuit board 48 is assembled between the keyboard 42 and the cabinets 50A and 50B. As in the case of the first embodiment, the electric circuit board 48 is formed in a rectangular shape that is long in the left-right direction, and is formed in a flat plate shape. A plurality of electrical switches and tone signal generators are fixed. In the second embodiment, the musical tone signal generator generates a musical tone signal having a pitch corresponding to the key detected by the plurality of electric switches in response to the key pressing / releasing operation.

As shown in the top view of the speaker device of FIG. 10, the cabinet 50A has a rectangular parallelepiped shape including an upper case 51 and a bottom plate 52 (see FIG. 11) similar to the cabinet 20 of the first embodiment. Also in this cabinet 50A, the length in the left-right direction is longer than the length in the front-rear direction, and the length in the vertical direction is shorter than the length in the front-rear direction. However, in the cabinet 50A, the length in the left-right direction is considerably shorter than that in the first embodiment, and the length in the front-rear direction is slightly longer than that in the first embodiment. The length in the vertical direction of the cabinet 50A is substantially the same as in the case of the first embodiment, and is relatively thin in the vertical direction as in the case of the first embodiment.

The upper case 51 is integrally formed of resin and is formed in a flat plate shape and a rectangular shape, and has an upper wall 51a, a front wall 51b, a rear wall 51c, a left wall 51d, and a right wall 51e that are orthogonal to each other. The bottom plate 52 (see FIG. 11) is formed in a flat plate shape and a rectangle having the same shape as the upper wall 51a of the upper case 51. The bottom plate 52 is brought into close contact with the top wall 51b, the rear wall 51c, the left wall 51d, the right wall 51e, and lower end surfaces of partition plates 51f1 to 51f6 described later on the upper surface of the upper case 51 with an adhesive. It is fixed to the lower surface of 51. Therefore, a rectangular parallelepiped space is formed in the cabinet 50A. In addition, a rectangular opening 51c1 is formed in the right portion of the rear wall 51c, and the opening 51c1 faces the left portion of the net (opening) provided on the rear surface of the case 41.

In the upper case 51, flat and rectangular partition plates 51f1 to 51f6 are integrally formed with the upper case 51, as shown in the cross-sectional view of FIG. The partition plate 51f1 extends in a direction perpendicular to both inner side surfaces of the upper wall 51a and the front wall 51b, the lower end surface thereof is positioned on the upper surface of the bottom plate 52, and the rear end surface thereof is positioned in front of the rear wall 51c. ing. The partition plate 51f2 extends in a direction perpendicular to both inner side surfaces of the upper wall 51a and the rear wall 51c, the lower end surface thereof is positioned on the upper surface of the bottom plate 52, and the front end thereof is positioned behind the front wall 51b. ing. The partition plate 51f2 is located to the right of the partition plate 51f1. The partition plate 51f3 extends in a direction perpendicular to both inner side surfaces of the upper wall 51a and the right wall 51e, its lower end surface is positioned on the upper surface of the bottom plate 52, and its left end surface is on the right side of the partition plate 51f2. It is located.

The partition plate 51f4 extends in a direction perpendicular to the inner surface of the upper wall 51a and extends leftward from an intermediate position of the partition plate 51f2. The lower end surface of the partition plate 51f4 is positioned on the upper surface of the bottom plate 52. Yes. The partition plate 51f4 is located in the middle in the front-rear direction between the rear wall 51c and the rear end surface of the partition plate 51f1, and the left end thereof is located to the right of the left wall 51d. The partition plate 51f5 extends in a direction perpendicular to the inner surface of the upper wall 51a and extends forward from the left end portion of the partition plate 51f4. The lower end surface of the partition plate 51f5 is positioned on the upper surface of the bottom plate 52. . The partition plate 51f5 is located in the middle of the left wall 51d and the partition plate 51f1 in the left-right direction, and its front end surface is located behind the front wall 51b. The partition plate 51f6 extends in a direction perpendicular to the inner surface of the upper wall 21a and extends rightward from the front end portion of the partition plate 51f2. The lower end surface of the partition plate 51f6 is positioned on the upper surface of the bottom plate 52. Yes. The partition plate 51f6 is located in the middle of the front wall 51b and the partition plate 51f3 in the front-rear direction, and the right end surface thereof is located to the left of the right wall 51e.

By such partition plates 51f1 to 51f6, between the upper wall 51a and the bottom plate 52, as indicated by an arrow in FIG. 10, from the position between the left end of the partition plate 51f4 and the inner surface of the left wall 51d. An air passage that gradually spreads to the opening 51c1 provided in the rear wall 51c is formed. This air passage is an air passage for propagating air vibrations by the speaker unit 60A, and is the above-described sound path S1. Also in this electronic keyboard instrument, the length of the cabinet 50A in the left-right direction is shorter than that in the first embodiment, but is longer than the length in the front-rear direction. It is formed in a long shape in the arrangement direction. The position between the left end of the partition plate 51f4 and the inner surface of the left wall 51d is the entrance of the sound path S1, and the opening 51c1 is the exit of the sound path S1. The sound path S1 becomes wider from the entrance toward the exit.

Further, in front of the entrance of the sound path S1, a region surrounded by the rear wall 51c, the left wall 51d and the partition plates 51f2 and 51f4 (more precisely, the rear wall 51c, the left wall 51d, the partition plate 51f2, and the partition plate). A substantially rectangular space is formed in a region surrounded by a plane extending 51f4 to the left wall 51d. This space is the air chamber S2. Also in this case, the horn portion of the speaker unit 60A is formed by the sound path S1 and the air chamber S2, and the vertical air vibration by the speaker unit 60A is bent 90 degrees in the air chamber S2 to become horizontal vibration, The vibration propagates in the arrangement direction of the plurality of keys through the sound path S1 having the longitudinal direction as the arrangement direction of the plurality of keys on the keyboard 12.

A circular through hole is formed at the position of the upper wall 51a facing the air chamber S2. And the speaker unit 60A is assembled | attached to the part of the upper wall 51a in which this through-hole is located. The through hole and the front side (upper surface) of the speaker unit 60A are opposed to the lower end surface of the opening of the conical wall 46 provided in the case 41 (see FIG. 9). Since the configuration of the speaker unit 60A and the assembly to the cabinet 50A are the same as those of the speaker unit 30 of the first embodiment, description thereof will be omitted.

Next, the cabinet 50B will be described. Since the cabinet 50B is configured to be symmetrical to the cabinet 50A described above, the drawings are omitted and the description of the same portions is also omitted. The cabinet 50B is arranged on the right side of the cabinet 50A in parallel with the upper surface of the keyboard 42 and below the keyboard 42. In the cabinet 50B, the exit of the sound path S1, that is, the opening provided in the rear wall of the cabinet 50B is located on the left side of the rear wall of the cabinet 50B, and on the right side portion of the net (opening) provided on the rear surface of the case 41. Opposite. The air chamber S <b> 2 is located at the right end of the cabinet 50 </ b> B and faces the lower end surface of the opening of the conical wall 47 provided in the case 41.

A circular through hole is formed at the upper wall position of the cabinet 50B facing the air chamber S2. The speaker unit 60B is assembled to the portion of the upper wall where the through hole is located. The through hole and the front side (upper surface) of the speaker unit 60B are opposed to the lower end surface of the opening of the conical wall 47 provided in the case 41 (see FIG. 9). Since the configuration of the speaker unit 60B and the assembly to the cabinet 50B are the same as those of the speaker unit 30 of the first embodiment, description thereof will be omitted.

In the speaker device configured as described above, if an electric signal that is a musical tone signal from the musical tone signal generator is supplied to the coils in the speaker units 60A and 60B, respectively, as in the case of the first embodiment, air vibrations are generated. Is generated from the upper side of the cabinets 50A and 50B upward. The musical sound passes through the inside of the conical walls 46 and 47 provided in the case 41, and is sounded to the outside as a musical sound by an electronic keyboard instrument from above the case 41 via the nets 44 and 45.

On the other hand, the air vibrations on the back side of the speaker units 60A and 60B also enter the sound path S1 from the entrance of the sound path S1 via the air chamber S2 and propagate through the sound path S1, as in the case of the first embodiment. Then, the sound generated by the air vibration is propagated to the outside from the exit of the sound path S1, that is, the opening 51c1 provided in the rear wall 51c of the cabinet 50A and the opening provided in the rear wall of the cabinet 50B, respectively, and the musical sounds due to the air vibration are transmitted to the cabinets 50A and 50B. It is generated from the rear side to the rear side. Musical sounds generated from the rear sides of the cabinets 50 </ b> A and 50 </ b> B are sounded to the outside as musical sounds by the electronic keyboard instrument from the rear of the case 41 through a net provided on the rear side surface of the case 41.

Also in the electronic keyboard instrument configured as described above, the length in the vertical direction of the cabinets 50A and 50B in which the speaker units 60A and 60B are assembled is made shorter than the length in the left and right direction and the front and rear direction, respectively. The speaker device is arranged below the keyboard 42. As a result, the backload horn type speaker device can be assembled even in a small electronic keyboard instrument having a thin thickness in the vertical direction, that is, in a direction perpendicular to the keyboard 12. As a result, an electronic keyboard instrument in which a backload horn type speaker device is assembled can be realized, and a good musical sound can be generated by the backload horn type speaker device. In the second embodiment, since the two speaker units 60A and 60B are provided, it is possible to generate a musical sound in stereo. In the electronic keyboard instrument, the cabinets 50A and 50B assembled with the speaker units 60A and 60B are arranged below the keyboard 42, and the electric circuit board 48 is arranged between the keyboard 42 and the cabinets 50A and 50B. As a result, the electric circuit board 48 and the cabinets 50A and 50B can be accurately incorporated in the electronic keyboard instrument.

Also in the second embodiment, the back load horn type speaker device is configured by assembling speaker units 60A and 60B similar to those of the first embodiment to cabinets 50A and 50B having sound paths. Therefore, also in the second embodiment, as in the case of the first embodiment, a high-frequency phase characteristic is improved, a sharp tone can be obtained, and a dynamic range of the tone can be widened. The volume can be increased.

c. Modification The electronic musical instrument according to the present invention is not limited to the first and second embodiments described above, and can be appropriately changed within the technical scope of the present invention.

In the electronic keyboard harmonica of the first embodiment, the exit of the sound path S1 is on the right side of the cabinet 20, but as in the case of the second embodiment, the exit of the sound path S1 in the cabinet 20 is the upper case 21. It may be provided on the rear wall 21c side, and a musical sound may be generated from the rear side surface of the case 11 of the electronic keyboard harmonica via the sound path S1. Further, in the electronic keyboard harmonica, there are cases where the performance is held by hand, and in many cases the performance is performed by hand, so that the front side of the speaker unit 30 is directed to the lower side of the case 11. Good.

In the second embodiment, the cabinets 50A and 50B in which the speaker units 60A and 60B are assembled are arranged directly below the keyboard 42. However, instead of this, the cabinets 50 </ b> A and 50 </ b> B may be arranged behind the keyboard 42. In this case, specifically, as shown in FIG. 12, the length of the case 41 of the electronic keyboard instrument is increased in the front-rear direction, and the cabinets 50A and 50B are arranged behind the keyboard 42 as indicated by broken lines in the figure. To do. The cabinets 50 </ b> A and 50 </ b> B may be positioned below the keyboard 42 or at the same height as the keyboard 42, but are arranged parallel to the upper surface of the keyboard 42. The configuration itself of the cabinets 50A and 50B including the speaker units 60A and 60B is the same. And the opening part 51c1 provided in the upper case 51 of cabinet 50A, 50B has opposed the net | network (opening) provided in the rear surface of case 41. FIG. In this case, the operation element 43 is provided on the left side of the keyboard 42. Further, the operation element 43 may be provided on the right side of the keyboard 42. In addition, about the cabinet 50B, the code | symbol is abbreviate | omitted also in this modification. Even in the modified example configured as described above, since the cabinets 50A and 50B having a small thickness in the vertical direction are arranged in parallel with the upper surface of the keyboard 42, the height in the vertical direction of the electronic keyboard instrument can be kept low. .

In the modification of FIG. 12, the right end of the cabinet 50A and the left end of the cabinet 50B are close to each other (substantially abut), but a gap is provided between the right end of the cabinet 50A and the left end of the cabinet 50B. The cabinets 50A and 50B may be arranged. Further, the positions of the cabinets 50A and 50B according to this modification are slightly shifted forward, the front portions of the cabinets 50A and 50B are located immediately below the keyboard 42, and the rear portions of the cabinets 50A and 50B are located behind the keyboard 42. The cabinets 50 </ b> A and 50 </ b> B may be arranged so as to straddle the rear end of the keyboard 42 so as to be positioned. Further, such modifications relating to the arrangement of the cabinets 50A and 50B can be applied to the electronic keyboard harmonica according to the first embodiment as long as the front-rear width can be increased.

In the said 1st and 2nd embodiment, the length of the left-right direction of cabinet 20,50A, 50B is made longer than the length of the front-back direction, and it extends in the left-right direction in sound path S1 in cabinet 20, 50A, 50B. The amount is larger than the amount of extension in the front-rear direction. However, when the length of the electronic keyboard instrument (or electronic keyboard harmonica) is long in the front-rear direction as in the modified example of FIG. 12, the length of the cabinets 20, 50A, 50B in the front-rear direction is longer than the length in the left-right direction. May be longer. In this case, for example, in the electronic keyboard instrument of FIG. 12, long cabinets 50 </ b> A and 50 </ b> B are arranged in the front-rear direction on the left and right outer sides of the keyboard 42. And the extension amount of the front-back direction in the sound path S1 in the cabinet 20, 50A, 50B should just be made larger than the extension amount of the left-right direction. Further, the length in the front-rear direction and the length in the left-right direction of the cabinets 20, 50A, 50B are made substantially the same, and the extension amount in the front-rear direction and the extension amount in the left-right direction in the sound path S1 in the cabinet 20, 50A, 50B May be substantially the same.

In the first and second embodiments, the sound paths S1 in the cabinets 20, 50A, 50B are extended in the left-right direction and the front-rear direction. However, these sound paths S1 are not inclined in the left-right direction and the front-rear direction, but are inclined at a predetermined angle with respect to the left-right direction and the front-rear direction, for example, 45 degrees, and extend obliquely with respect to the left-right direction and the front-rear direction. You may make it make it.

In the first and second embodiments, the cabinet 20, 50A, 50B of the speaker device is formed into a thin rectangular parallelepiped shape in which the horizontal direction is longer than the front-rear direction and the vertical direction is shorter than the front-rear direction. Speaker units 30, 60A, and 60B are provided on the upper surfaces of 50A and 50B, and the usage mode with the speaker units 30, 60A, and 60B facing the upper surface is illustrated. However, the present invention is not limited to this, and the speaker units 30, 60 </ b> A, and 60 </ b> B may be used in a state in which the speaker units 30, 60 </ b> A, and 60 </ b> B are directed to the side surfaces. Further, the shapes of the cabinets 20, 50A, 50B and the surfaces of the cabinets 20, 50A, 50B on which the speaker units 30, 60A, 60B are arranged are not limited to those illustrated. For example, the shape of the cabinets 20, 50A, 50B may not be a rectangular parallelepiped, and the speaker units 30, 60A, 60B may be disposed on the side surfaces of the cabinets 20, 50A, 50B. In these cases, direct musical sounds from the speaker units 30, 60A, 60B that do not pass through the sound path S1 in the cabinets 20, 50A, 50B are generated from the side and bottom surfaces of the electronic keyboard harmonica and the electronic keyboard instrument. .

Furthermore, in the electronic keyboard harmonica according to the first embodiment and the electronic keyboard according to the second embodiment, the musical sound from the front side of the speaker units 30, 60A, 60B is transmitted to the inside of the walls 17, 46, 47. You may make it generate | occur | produce directly from the upper surface of the case 11 of an electronic keyboard harmonica, and the case 41 of an electronic keyboard instrument, without making it pass. In these cases, the various walls of the cabinets 20, 50A, 50B in the part where the air chamber S2 is located are extended upward, so that the speaker units 30, 60A, 60B are part of the cabinets 20, 50A, 50B including the sound path S1. And the walls 17, 46 and 47 may be omitted.

This application is based on a Japanese patent application (Japanese Patent Application No. 2015-196650) filed on October 2, 2015, the contents of which are incorporated herein by reference.

ADVANTAGE OF THE INVENTION According to this invention, a favorable musical sound can be generated using the back load horn type speaker apparatus in an electronic musical instrument with a thin thickness in the vertical direction.

DESCRIPTION OF SYMBOLS 11, 41 ... Case, 12, 42 ... Keyboard, 18, 48 ... Electric circuit board, 20, 50A, 50B ... Cabinet, 21 ... Upper case, 21a ... Upper wall, 21a1 ... Through-hole, 21b ... Front wall, 21c ... Rear wall, 21d ... left wall, 21e1 to 21e8, 51f1 to 51f6 ... partition plate, 22 ... bottom plate, 30, 60A, 60B ... speaker unit, 31 ... chassis, 32 ... yoke, 33 ... magnet, 34 ... bobbin, 35 ... Coil, 36 ... cone, 37 ... damper, 38 ... center cap, S1 ... sound path, S2 ... air chamber

Claims (5)

An electronic musical instrument that includes a keyboard composed of a plurality of keys and generates a musical tone by pressing a plurality of keys,
Having at least one speaker device;
The speaker device
A cabinet provided with a sound path in which the length in the vertical direction is shorter than the length in the left-right direction and the front-back direction, and air vibrations are propagated inside;
A speaker unit assembled in the cabinet, with the front side facing the outside of the cabinet and the back side facing the space inside the cabinet and in front of the sound path,
The speaker device is a backload horn type speaker device that guides air vibrations by the speaker unit to the sound path and guides air vibrations propagated through the sound path to the outside.
The speaker device is an electronic musical instrument that is arranged in parallel with the upper surface of the keyboard so that a horizontal direction thereof is an arrangement direction of the plurality of keys. The at least one speaker device is one speaker device;
The length of the cabinet of the said one speaker apparatus in the left-right direction is larger than the length of the front-back direction, The said one speaker apparatus is arrange | positioned so that the left-right direction may become the arrangement direction of these several keys. Electronic musical instrument. The at least one speaker device is two speaker devices;
The electronic musical instrument according to claim 1, wherein the two speaker devices are arranged so as to correspond to a right side portion and a left side portion of the keyboard. The electronic musical instrument according to any one of claims 1 to 3, wherein the speaker unit is assembled to an upper surface of the cabinet. The electrical circuit board provided with the electrical switch which arrange | positions the said speaker apparatus under the said keyboard, and provided the electrical switch which detects pressing / release of these keys is arrange | positioned between the said keyboard and the said speaker apparatus. 4. The electronic musical instrument according to any one of 4 above.

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