1. An electronic musical instrument, comprising:

a speaker that emits sound in a first direction in accordance with a performance operation;

an internal component including a substrate;

a housing that houses the speaker and the internal component, and that has a first region and a second region, the first region corresponding to a back surface of the speaker, the second region corresponding to a back surface of the internal component and not corresponding to the back surface of the speaker; and

and a sound emission member that is provided on the installation surface side and in the second region, and emits sound in a second direction opposite to the first direction from sound in a sound space formed around the speaker.

2. The electronic musical instrument according to claim 1,

the sounding member includes any one of a passive radiator and at least a part of the bass reflex duct.

3. The electronic musical instrument according to claim 1 or 2,

the speaker includes an intermediate member that is provided in the housing, and that forms the acoustic space by being fixed to the housing and accommodating the speaker therein,

the intermediate member has a region in which the speaker is disposed and a region in which the internal component is disposed outside.

4. The electronic musical instrument according to claim 3,

the height from the bottom surface to the top surface of the region of the intermediate member in which the speaker is disposed is higher than the height from the bottom surface to the top surface of the region in which the internal component is disposed.

5. The electronic musical instrument according to claim 3 or 4,

the intermediate member has a sound emission hole in a region where the speaker is disposed.

6. The electronic musical instrument according to any one of claims 3 to 5,

the intermediate member has a side wall portion extending from an outer edge portion of a top surface in an area where the speaker is arranged inside and an area where the internal component is arranged outside to a bottom surface.

7. The electronic musical instrument according to any one of claims 3 to 6,

the intermediate member has an inclined portion at a boundary between a region where the speaker is disposed inside and a region where the internal component is disposed outside.

8. The electronic musical instrument according to claim 2,

the casing has a first fixing portion and a second fixing portion, the first fixing portion at least fixes the plate part of the sounding member of which the length in the long side direction of the bass reflex channel is a first length; the second fixing portion fixes the plate member having a length in the longitudinal direction of the bass reflex duct of a second length shorter than the first length.

9. The electronic musical instrument according to claim 2 or 8,

the shell is a shell body which is composed of a shell body,

a plurality of U-shaped grooves extending in the longitudinal direction of the bass reflex duct are provided on the setting surface side,

the bottom of the plurality of U-shaped grooves in the second region has a plurality of sound holes as bass reflex ports arranged in the short side direction and the long side direction of the bass reflex duct.

10. The electronic musical instrument according to claim 9,

reinforcing ribs extending in the long side direction of the bass reflex duct are provided on the side grooves of the plurality of U-shaped grooves in the second region.

11. An electronic musical instrument, comprising:

a speaker that emits sound in a first direction in accordance with a performance operation;

a case that houses the speaker and has a sound hole as a bass reflex port in a second region that does not include a first region corresponding to a back surface of the speaker, the sound hole being configured to emit sound in a second direction opposite to the first direction from sound in a sound space formed around the speaker; and

a plate member fixed to the housing in the second region, forming a bass reflex duct together with an inner wall of the housing.

12. The electronic musical instrument according to claim 11,

the case has a first fixing portion and a second fixing portion, the first fixing portion at least fixes the plate member whose length in the long side direction of the bass reflex duct is a first length, and the second fixing portion fixes the plate member whose length in the long side direction of the bass reflex duct is a second length shorter than the first length.

13. The electronic musical instrument according to claim 11 or 12,

the speaker includes an intermediate member that is provided in the housing, and that forms the acoustic space by being fixed to the housing and accommodating the speaker therein,

the intermediate member has a region in which the speaker is disposed and a region in which the internal component is disposed outside.

14. The electronic musical instrument according to claim 13,

the height from the bottom surface to the top surface of the region of the intermediate member in which the speaker is disposed is higher than the height from the bottom surface to the top surface of the region in which the internal component is disposed.

15. The electronic musical instrument according to claim 13 or 14,

the intermediate member has a sound emission hole in a region where the speaker is disposed.

16. The electronic musical instrument according to any one of claims 13 to 15,

the intermediate member has a side wall portion extending from an outer edge portion of a top surface in an area where the speaker is arranged inside and an area where the internal component is arranged outside to a bottom surface.

17. The electronic musical instrument according to any one of claims 13 to 16,

the intermediate member has an inclined portion at a boundary between a region where the speaker is disposed inside and a region where the internal component is disposed outside.

18. The electronic musical instrument according to any one of claims 11 to 17,

the shell is a shell body which is composed of a shell body,

a plurality of U-shaped grooves extending in the longitudinal direction of the bass reflex duct are provided on the setting surface side,

the bottom of the plurality of U-shaped grooves in the second region has a plurality of sound holes as the bass reflex ports arranged in the short side direction and the long side direction of the bass reflex duct.

19. The electronic musical instrument according to claim 18,

reinforcing ribs extending in the long side direction of the bass reflex duct are provided on the side grooves of the plurality of U-shaped grooves in the second region.

20. An electronic keyboard instrument, comprising:

a keyboard;

a plurality of speakers that produce sound in a first direction in accordance with a performance operation;

a housing that houses at least the plurality of speakers; and

and a plurality of sound emitting members provided between the plurality of speakers on the installation surface side, and configured to emit sound in a second direction opposite to the first direction from sound in sound spaces formed around the plurality of speakers.

Background

In the patent document (japanese unexamined patent application publication No. 6-26386), a sound emission hole for emitting sound from a front surface portion (upper portion) of a speaker is formed in an upper case. The lower case is formed with a sound hole for emitting sound from a back surface portion (lower portion) of the speaker, and the sound hole is surrounded by the cylindrical body. The rear surface portion of the speaker is sealed in a state of being inserted into the cylindrical body, and the sound emitted from the rear surface portion of the speaker is released to the outside of the case through the sound emission hole of the lower case without leaking into the inside of the case.

Disclosure of Invention

An electronic musical instrument according to an embodiment of the present invention includes:

a speaker that emits sound in a first direction in accordance with a performance operation;

an internal component including a substrate;

a housing that houses the speaker and the internal component, and that has a first region and a second region, the first region corresponding to a back surface of the speaker, the second region corresponding to a back surface of the internal component and not corresponding to the back surface of the speaker; and

and a sound emission member that is provided on the installation surface side and in the second region, and emits sound in a second direction opposite to the first direction from sound in a sound space formed around the speaker.

Drawings

Fig. 1A is a perspective view of an electronic keyboard instrument of the embodiment, and fig. 1B is an exploded view of fig. 1A.

Fig. 2A is a perspective view of the electronic keyboard instrument with the first casing omitted, and fig. 2B is a sectional view taken along line a-a of fig. 2A.

Fig. 3 is an exploded view of a part of the cross-sectional view of fig. 2B.

Fig. 4 is a partially exploded perspective view of the electronic keyboard instrument.

Fig. 5A is a top view of the intermediate member, and fig. 5B is a bottom view of the intermediate member.

Fig. 6 is a partial plan view of the second housing.

Fig. 7 is a partial longitudinal sectional view around a boss for a fixing hole.

Fig. 8 is an exploded view of fig. 7.

Fig. 9A is an enlarged view of a part of the sectional view of fig. 2B, and fig. 9B is a partially enlarged sectional view taken along line C-C of fig. 9A.

Fig. 10 is a bottom view of the electronic keyboard instrument.

Fig. 11 is a side view of the electronic keyboard instrument.

Detailed Description

Hereinafter, a mode of an electronic musical instrument for carrying out the present invention will be described in detail with reference to the drawings. In the present embodiment, an electronic keyboard instrument (keyboard) is shown as an example of the electronic musical instrument according to the present invention. The present invention is not limited to the embodiments described below, and can be implemented by being appropriately modified within a range not changing the gist thereof. In the following drawings, some of the structures may be omitted for convenience of explanation.

In the following description, "up", "down", "left", "right", "front", and "rear" are used with reference to directions indicated by arrows in the drawings unless otherwise specified. However, the orientation of each component in the following embodiments is merely an example, and can be changed to any orientation.

Fig. 1A is a perspective view of an electronic keyboard instrument of the embodiment. Fig. 1B is an exploded view of fig. 1A. As shown in fig. 1A and 1B, the electronic keyboard instrument 10 includes a casing 11, a keyboard 12, and 2 speakers 13 (not shown in fig. 1A) housed inside the casing 11, and sounds from the speakers 13 in response to a musical performance operation of the keyboard 12.

The housing 11 includes an upper (front) first housing 15 from which the speaker 13 emits sound and a lower (back) second housing 16. The first case 15 and the second case 16 are formed with the left-right direction as the longitudinal direction.

The first casing 15 is provided so as to cover a substantially rear half portion of the second casing 16 and an area along the outer edge when viewed from above. A central portion in the left-right direction behind the first casing 15 is a display operation portion 17 provided with a display, a lighting portion such as an LED, and an operation member such as a switch. In the first casing 15, sound emission areas 18 are provided on both left and right sides of the display operation unit 17, and a cover 18a is provided on a speaker grill (not shown) having a plurality of holes formed in a mesh shape in the sound emission areas 18.

White keys and black keys of the keyboard 12 are mounted on the front side portion of the second casing 16 so as to be aligned along the longitudinal direction (left-right direction) of the second casing 16. In the present embodiment, the arrangement direction of the keyboard 12 and the short side direction of each key are the left-right direction, and the long side direction of each key is the front-back direction.

The speaker 13 is provided in the housing 11 so as to emit sound in a first direction D1 parallel to the upper direction. Here, the electronic keyboard instrument 10 includes an intermediate member 20 (not shown in fig. 1A) that accommodates the speaker 13 therein by the second case 16 fixed to the case 11. The speaker 13 is attached to the second casing 16 via the intermediate member 20 in a state where the first casing 15 is detached from the second casing 16 (before the first casing 15 and the second casing 16 are combined). The intermediate member 20 is also provided in the housing 11 between the first housing 15 and the second housing 16.

Fig. 2A is a perspective view of the electronic keyboard instrument with the first casing omitted. As shown in fig. 2A, an internal member 21 including a substrate 21a is housed in the housing 11 between the 2 speakers 13 arranged on the left and right. The internal member 21 is disposed directly below (at a position overlapping in the vertical direction) the display operation unit 17 (see fig. 1). The board 21a is connected to each part of the display operation unit 17, the speaker 13, and the like via wires and terminals, and is used for various controls of the electronic keyboard instrument 10.

Fig. 2B is a sectional view taken along line a-a of fig. 2A. As shown in fig. 2B, the second case 16 of the case 11 has a first region S1 and a second region S2. The first region S1 is a region corresponding to the lower surface (rear surface) of the speaker 13, and is a region where the speaker 13 is projected (overlapped) in the vertical direction. The second region S2 is a region corresponding to the lower surface (rear surface) of the inner member 21, and is a region not corresponding to the lower surface of the speaker 13, in other words, a region where the speaker 13 is not projected (does not overlap) in the up-down direction. Therefore, the second region S2 does not include the first region S1 corresponding to the lower surface of the speaker 13.

Here, the electronic keyboard instrument 10 of the present embodiment is provided with the speakers 13 and the intermediate member 20 on the rear left and right sides, and the structure including these is substantially symmetrical with the center position of the electronic keyboard instrument 10 in the left-right direction interposed therebetween. Therefore, the speaker 13 and the intermediate member 20 positioned on the right side will be described below, and the illustration and description of the speaker 13 and the intermediate member 20 positioned on the left side may be omitted.

As shown in fig. 2A, the intermediate member 20 includes a main region 23 as a first region in which the speaker 13 is disposed, and an extension region 24 as a second region in which the internal member 21 is disposed on the upper side. In other words, the internal member 21 is disposed in a region closer to the center portion in the left-right direction of the entire keyboard 12 (not shown in fig. 2B) than the main region 23, and the internal member 21 is disposed in a space outside the upper portion of the extended region 24. The extension area 24 is formed to include an area between the left and right 2 speakers 13.

Fig. 3 is an exploded view of a part of the cross-sectional view of fig. 2B. Fig. 4 is a partially exploded perspective view of the electronic keyboard instrument. The intermediate member 20 is formed to have a longer length in the left-right direction than in the front-rear direction, and the main region 23 and the expanded region 24 are also formed to have longer lengths in the left-right direction than in the front-rear direction. Bottom surfaces 23c and 24c serving as lower end surfaces of the main region 23 and the expanded region 24 are formed along the same plane parallel to the front-rear direction and the left-right direction.

The main region 23 includes: a top wall 26 forming a top surface (upper surface) 23a of the main region 23; a front side wall (side wall portion) 27 (not shown in fig. 3) connected to a front end of the top wall 26; and a rear side wall (side wall portion) 28 connected to the rear end of the top wall 26. The main region 23 includes: an intermediate wall 30 connected to the end portions on the expansion region 24 side of each of the top wall 26, the front side wall 27, and the rear side wall 28; and an outer side wall (side wall portion) 31 connected to respective ends of the top wall 26, the front side wall 27, and the rear side wall 28 on the opposite side from the expansion area 24.

The bottom surface 23c of the main region 23 is formed by the lower end surfaces of the front side wall 27, the rear side wall 28, and the outer side wall 31. Therefore, the front side wall 27, the rear side wall 28, and the outer side wall 31 extend in the up-down direction from the outer edge portion 23b of the top surface 23a to the bottom surface 23 c.

The speaker 13 has a tapered portion whose length in the left-right direction is longer than that in the front-rear direction, and the length in the left-right direction of the main region 23 is also longer than that in the front-rear direction depending on the shape of the tapered portion. The top wall 26 which becomes the inside of the main area 23 has a sound emitting hole 26a at a position corresponding to the speaker 13. In the sound emitting hole 26a, the length in the left-right direction is longer than the length in the front-rear direction, similarly to the main region 23. The speaker 13 is fixed in a state of being pressed to the lower surface of the top wall 26 near the formation edge of the sound emission hole 26a via a suitable cushioning material.

The expansion region 24 includes: an upper wall 33 forming a top surface (upper surface) 24a of the expansion region 24; and rib side walls (side wall portions) 34 protruding downward from three outer edge portions 24b except for portions adjacent to the main region 23 of the top surface 24 a. The bottom surface 24c of the expansion region 24 is formed by the lower end surface of the rib side wall 34. Therefore, the rib side walls 34 extend to protrude from the outer edge portion 24b of the top surface 24a of the expanded region 24 to the bottom surface 24c in the up-down direction.

The intermediate member 20 has the above-described respective configurations and is provided in a box shape with its lower side open to form a speaker box. In the intermediate member 20, the height from the bottom surface 23c to the top surface 23a of the main region 23 is formed to be higher than the height from the bottom surface 24c to the top surface 24a of the expansion region 24. In other words, the main region 23 and the extended region 24 have different vertical widths, and the extended region 24 is formed at a position lower than the main region 23 (lower position). Therefore, a space can be formed above the expanded region 24 at a position lower than the top surface 23a of the main region 23. The speaker 13 is fixed to the top wall 26 of the main area 23 and is provided in a size exposed from the bottom surface 23c of the main area 23.

The intermediate member 20 has an inclined portion 36 at a boundary between the main region 23 and the expanded region 24. The inclined portion 36 is formed to connect between the lower end of the intermediate wall 30 in the main region 23 and the upper wall 33 of the expansion region 24. The inclined portion 36 is formed in an inclined direction that descends as it approaches the upper wall 33 from an upper end that is a boundary position with the intermediate wall 30 and gradually moves away from the intermediate wall 30.

Fig. 5A is a top view of the intermediate member, and fig. 5B is a bottom view of the intermediate member. As shown in fig. 5A and 5B, the intermediate member 20 has 6 mounting holes 38 and 2 fixing holes 39.

The mounting holes 38 are formed near the four corners of the intermediate member 20 and on the front and rear sides of the position overlapping the inclined portion 36 at the center in the left-right direction of the intermediate member 20 when viewed in the up-down direction. The mounting holes 38 are formed inside the mounting hole bosses 40, and the bottom surfaces of the mounting hole bosses 40 are formed at positions protruding downward from the bottom surfaces 23c, 24c of the main region 23 and the expanded region 24 (see fig. 3). In a state where the intermediate member 20 is viewed from below, that is, in a state shown in fig. 5B, the mounting hole boss 40 at a position overlapping the inclined portion 36 has a semicircular arc-shaped outer peripheral surface on the inner side.

The fixing holes 39 are formed on the main region 23 side, and specifically, 1 fixing hole is formed on each of the left and right sides of the main region 23 when viewed in the vertical direction. Each fixing hole 39 is formed inside a fixing hole boss 41, and the fixing hole boss 41 is formed in a shape obtained by cutting out a part of a cylindrical body. The bottom surface of the fixing hole boss 41 is formed at a position above the bottom surfaces 23c and 24c of the main region 23 and the expanded region 24 (see fig. 3).

Fig. 6 is a partial plan view of the second housing. As shown in fig. 6 in addition to fig. 4, the second casing 16 includes a base portion 43 provided substantially in parallel with the front-rear direction and the left-right direction, and a bottom wall as the entire casing 11 is formed by the base portion 43. A frame-shaped rib 44 is formed at a fixed position of the intermediate member 20 (not shown in fig. 6) on the upper surface side of the base portion 43. Further, 6 intermediate member attachment bosses 45 and 2 case fixing bosses 46 are formed on the upper surface side of the base portion 43 inside the frame-like rib 44.

The frame-shaped rib 44 is provided at a position corresponding to each of the bottom surfaces 23c, 24c of the intermediate member 20, and is formed in a substantially rectangular shape along a shape projecting from the intermediate member 20 when viewed in the vertical direction. Therefore, the bottom surfaces 23c and 24c of the intermediate member 20 are placed in contact with the upper end surfaces of the frame-shaped ribs 44, and in this contact state, no gap is formed between the upper end surfaces of the frame-shaped ribs 44 and the bottom surfaces 23c and 24c of the intermediate member 20 (see fig. 9A).

The intermediate member mounting boss 45 is formed at a position 6 corresponding to the mounting hole 38 of the intermediate member 20. Each intermediate member mounting boss 45 is formed with a screw hole, and a screw 50 (not shown in fig. 6) inserted through the mounting hole 38 (see fig. 5A) is screwed into the screw hole.

The upper end surface of the intermediate member attachment boss 45 is formed lower than the frame-shaped rib 44. Specifically, the upper end surface of the intermediate member mounting boss 45 is formed lower than the upper end of the frame-shaped rib 44 by the amount of projection of the mounting hole boss 40 projecting downward from the bottom surfaces 23c, 24c of the intermediate member 20. Therefore, when the intermediate member 20 is placed on the frame-shaped rib 44, the bottom surface of the mounting hole boss 40 comes into contact with the upper end of the intermediate member mounting boss 45.

In this state, the mounting hole bosses 40 are fastened by the screws 50 and the intermediate member mounting bosses 45 by inserting the screws 50 through the mounting holes 38 of the intermediate member 20 and screwing the screws 50 into the screw holes of the intermediate member mounting bosses 45. By this fastening, the intermediate member 20 is fixed to the second housing 16 (see fig. 1B) of the housing 11, and can maintain the state of being attached to the second housing 16 in a state where the first housing 15 is separated from the second housing 16.

When fixed in this manner, the acoustic space 51 (see fig. 9) is formed by the intermediate member 20, the speaker 13, the frame-shaped rib 44 of the second housing 16, and the base portion 43, and is closed by removing a sound hole described later. In other words, the acoustic space 51 is an inner space surrounded by the intermediate member 20, the speaker 13, the frame-shaped rib 44, and the base portion 43.

The intermediate member 20 is fixed to the second casing 16, and thereby the speaker 13 is housed in the acoustic space 51 inside. In addition, an acoustic space 51 is formed around the speaker 13. The acoustic space 51 is formed as a space in which sound radiated downward from the speaker 13 resonates. In the acoustic space 51, sound is prevented from leaking between the upper end surface of the frame-shaped rib 44 and the bottom surfaces 23c and 24c of the intermediate member 20.

The case fixing boss 46 is formed at a position 2 corresponding to the fixing hole 39 of the intermediate member 20. The upper end surface of the case fixing boss 46 is formed higher than the frame-shaped rib 44 (see fig. 3), and when the intermediate member 20 is fixed to the second case 16, the bottom surface of the fixing hole boss 41 comes into contact with the upper end of the case fixing boss 46.

Fig. 7 is a partial longitudinal sectional view around a boss for a fixing hole. Fig. 8 is an exploded view of fig. 7. The cutting positions of the cross sections of fig. 7 and 8 are positions along the line B-B of fig. 6. Fig. 7 shows a peripheral structure of the boss 41 for fixing hole on the outer wall 31 side in the main region 23, and shows a state in which the intermediate member 20 is fixed to the second housing 16 and the first housing 15 and the second housing 16 are combined. In this state, the first housing 15 includes a downward projection 15a projecting downward and inserted into the fixing hole boss 41. The tip of the downward boss 15a is a small diameter portion 15b and is inserted into the fixing hole 39. A screw hole 15c extending in the up-down direction is formed in the downward boss 15 a.

The case fixing boss 46 includes an annular rib 46a formed on an upper end surface thereof and a top surface portion 46b on which the annular rib 46a is erected. A hole 46c through which the screw 52 is inserted is formed in the top surface portion 46b and inside the annular rib 46 a. The inner peripheral shape of the annular rib 46a is formed to be the same as or slightly larger than the outer peripheral shape of the small diameter portion 15b so that they are fitted. Tapered surfaces are formed at the respective inner peripheral upper end portions of the fixing hole 39 and the annular rib 46 a.

In a state where the intermediate member 20 is fixed to the second casing 16, the bottom surface of the fixing hole boss 41 contacts the upper end surface of the annular rib 46a of the casing fixing boss 46, and the fixing hole 39 and the hole 46c of the casing fixing boss 46 are positioned on the same center line. In this state, by covering and combining the first housing 15 from above the second housing 16, the downward boss 15a of the first housing 15 is inserted into the boss 41 for fixing hole. At this time, the small diameter portion 15b serving as the tip of the downward boss 15a penetrates the fixing hole 39 and is fitted into the annular rib 46 a.

In this fitted state, the screw 52 is screwed into the screw hole 15c of the downward boss 15a from below the case fixing boss 46 through the hole 46c and the fixing hole 39. Thereby, the top surface portion 46b of the case fixing boss 46 is fastened by the screw 52 and the downward boss 15a, and the state in which the first case 15 and the second case 16 are combined is fixed. The fixing hole boss 41 is fastened by the downward boss 15a and the case fixing boss 46, and the intermediate member 20 is fixed in a state of being sandwiched between the first case 15 and the second case 16. Here, the fixing hole 39 is used to fix the first casing 15, the second casing 16, and the intermediate member 20 to each other.

Although the periphery of the boss 41 for fixing hole on the outer wall 31 side of the main region 23 is illustrated in fig. 7 and 8, the same configuration is adopted around the other boss 41 for fixing hole. As shown in fig. 6, a case fixing boss 46 is also formed outside the frame-like rib 44. The case fixing bosses 46 are not used for fixing the intermediate member 20, but are used for fixing the first case 15 and the second case 16.

Fig. 9A is an enlarged view of a part of the cross-sectional view of fig. 2B. As shown in fig. 9A, the electronic keyboard instrument 10 includes the board member 60 serving as a sound emitting member provided in the second area S2. By providing the plate members 60 in the second regions S2 at 2, respectively, 2 speakers 13 are arranged (see fig. 2B). The electronic keyboard instrument 10 is provided with a bass reflex duct 61 formed by the board member 60, in other words, the board member 60 forms a part of the bass reflex duct 61. The bass reflex paths 61 extend in the left-right direction, and are formed in the same direction as the long side direction.

The board member (sound emitting member) 60 is provided on the installation surface side of the lower case. In the present embodiment, the speaker 13 emits sound in the upward direction, and emits sound to the setting surface side (downward direction) via the bass reflex duct 61 in the acoustic space in which the speaker 13 is arranged. By sounding to the setting surface side (downward direction) via the bass reflex duct 61, bass is further enhanced.

The electronic keyboard instrument 10 includes a sound hole 62 (see also fig. 6) as a bass reflex port formed at a position facing the board member 60. The sound hole 62 communicates with the internal space of the bass reflex duct 61. In the electronic keyboard instrument 10, the sound in the sound space 51 is emitted in the second direction D2 parallel to the lower direction opposite to the first direction D1 (the upper direction) through the bass reflex duct 61 including the board member 60 and the tone holes 62.

As shown in fig. 4, the bass reflex duct 61 is formed by a base portion 43 forming an inner wall of the second casing 16, a duct rib 63 provided upright from the base portion 43, and a plate member 60 provided above the duct rib 63.

The duct rib 63 is formed in an コ shape (in other words, a C shape with right angles in a top view) inside the frame-shaped rib 44 and in a region of the intermediate member 20 covered by the expanded region 24 (see fig. 6). The duct rib 63 is formed continuously by 2 ribs (1 rib is not shown in fig. 4) extending in parallel to the left-right direction and 1 rib extending between the end portions of the 2 ribs on the side (left side) opposite to the speaker 13, and opens the speaker 13 side (right side).

The plate member 60 is placed on the upper end of the channel rib 63. The plate member 60 includes a main wall 65 parallel to the front-rear direction and the left-right direction, and a triple wall 66 protruding downward from the lower surface of the main wall 65. The three-side wall 66 is provided at a position corresponding to the passage rib 63, and is formed in an コ shape similar to the passage rib 63 when viewed from the top-bottom direction. Therefore, the lower end surface of the three-side wall 66 formed as the plate member 60 is placed on the upper end surface of the channel rib 63 in contact therewith, and in this contact state, no gap is formed between the three-side wall and the channel rib 63 (see fig. 9A).

In the plate member 60, a plurality of holes are formed on both front and rear sides of the main wall 65, and among the plurality of holes, holes at four corners of the main wall 65 marked with reference numeral 67 in fig. 4 are used as plate member mounting holes 67.

The plate member 60 is formed so that the length in the left-right direction, which is the longitudinal direction, is a first length L1. Here, in the present embodiment, a plate member 60A (shown by a two-dot chain line in fig. 4) having a length in the left-right direction shorter than that of the plate member 60 can be selected and used. The plate member 60A has a length in the left-right direction set to a second length L2 shorter than the first length L1, and in the present embodiment, the second length L2 is set to a length approximately half of the first length L1. The plate member 60A also includes a main wall 65 and a three-side wall 66, and plate member mounting holes 67 are formed at four corners of the main wall 65.

The second housing 16 includes 6 bosses (see fig. 6, and 3 bosses on the front side are not shown in fig. 4) formed on the upper surface side of the base portion 43 and on the front and rear sides of the duct rib 63. Of the 6 bosses, 2 bosses formed at positions near the right end of the channel rib 63 (positions closer to the speaker 13) are set as the first fixing portions 69. Of the 6 bosses, 2 bosses formed at positions near the middle of the channel rib 63 in the left-right direction are provided as the second fixing portions 70. Of the 6 bosses, 2 bosses formed at positions near the left end of the tunnel rib 63 (positions on the opposite side of the speaker 13) are used as the third fixing portions 71.

The first fixing portion 69 and the third fixing portion 71 are formed at positions corresponding to the plate member mounting holes 67 in a state where the three-side wall 66 of the plate member 60 is placed on the tunnel rib 63, for fixing the plate member 60 of the first length L1. On the other hand, the second fixing portion 70 and the third fixing portion 71 are formed at positions corresponding to the plate member mounting holes 67 in a state where the three-side wall 66 of the plate member 60A is placed on the tunnel rib 63, for fixing the plate member 60A having the second length L2.

Screw holes are formed in the fixing portions 69 to 71, and screws 73 inserted through the plate member mounting holes 67 are screwed into the screw holes. By this screwing, the peripheral portion of the plate member mounting hole 67 is fastened to the distal ends of the fixing portions 69 to 71 by the screw 73, and the plate members 60 and 60A are fixed to the second housing 16. In addition, the second fixing portion 70 is not used when the plate member 60 of the first length L1 is fixed, and the first fixing portion 69 is not used when the plate member 60A of the second length L2 is fixed.

The bass reflex duct 61 is formed in a rectangular tube shape having a longer length in the left-right direction than in the front-back direction, and is flat in the up-down direction. The bass reflex duct 61 has a right side opened on the side of the speaker 13 and a left side and front and rear sides and upper and lower sides closed on the opposite side to the speaker 13 (see fig. 9).

The second casing 16 includes a plurality of U-shaped grooves 75, and the plurality of U-shaped grooves 75 are formed on the upper surface of the inner surface of the base portion 43 and extend in the left-right direction in the same direction as the longitudinal direction of the bass reflex duct 61. In the acoustic space 51, the sound hole 62 and the speaker 13 are separated in the left-right direction, and therefore the U-shaped groove 75 extends in a direction connecting them.

Fig. 9B is an enlarged partial cross-sectional view taken along line C-C of fig. 9A. As shown in fig. 9B, the U-shaped groove 75 is formed in an arc-like depression in a cross-sectional shape perpendicular to the extending direction, and is formed in a wave shape by a plurality of U-shaped grooves 75 provided adjacent to each other in the front-rear direction. The U-shaped groove 75 is also formed in the lower surface that is the outer surface of the base portion 43 (see also fig. 10).

Reinforcing ribs 77 extending in the left-right direction (the direction perpendicular to the plane of the paper in fig. 9B) are formed in the side grooves of the plurality of U-grooves 75 in the formation region of the sound holes 62, in other words, at the boundary positions of U-grooves 75 adjacent in the front-rear direction. Further, a sound hole 62 is formed in the bottom of the plurality of U-shaped grooves 75 in the second region S, and the sound hole 62 is set to a size that fits within the front-rear width of the U-shaped groove 75.

As shown in fig. 4 and 6, the sound hole 62 is formed by a plurality of circular holes that penetrate the base portion 43 of the second casing 16 in the vertical direction. Therefore, the sound hole 62 is present on the lower surface of the second casing 16 (see fig. 10). In the present embodiment, the sound holes 62 are formed in a matrix shape in which 4 rows are arranged in each of the front-back direction and the left-right direction (the long-side and short-side directions of the bass reflex duct 61).

Returning to fig. 9A, the sound hole 62 is formed in the bass reflex duct 61 at a position closer to the left, in other words, at a position as far as possible from the speaker 13 in the bass reflex duct 61. Therefore, the three-side wall 66 of the plate members 60 and 60A forming the bass reflex duct 61 is surrounded on the left side (the side opposite to the speaker 13) and the front and rear sides of the sound hole 62.

The formation positions of the reinforcing ribs 77 in the right-left direction are slightly exposed to the right and left sides of the formation region of the sound hole 62. Therefore, the reinforcing ribs 77 are formed in such a manner as to partition the sound holes 62 arranged in the front-rear direction. The right end side (the side opposite to the speaker 13) of the reinforcing rib 77 is formed in an inclined shape.

Fig. 10 is a bottom view of the electronic keyboard instrument. As shown in fig. 10, a recess 80 as a grip portion into which the user's fingertips can be inserted is formed in the center portion in the left-right direction behind the second casing 16 of the casing 11. Therefore, the user can carry the electronic keyboard instrument 10 while holding it by inserting the fingertips into the recessed portions 80. The recess 80 is formed at a position vertically overlapping the display operation portion 17 (see fig. 1B) of the first casing 15. As shown in fig. 2B, the recess 80 is formed between the 2 speakers 13, and the bass reflex duct 61 and the extension region 24 of the intermediate member 20 are provided in a region sandwiched between the speakers 13 and the recess 80.

Fig. 11 is a side view of the electronic keyboard instrument. As shown in fig. 10 and 11, the case 11 includes a plurality of legs 81 protruding from the lower surface of the second case 16. With the leg 81, when the electronic keyboard instrument 10 is placed on a predetermined flat installation surface F, a gap can be generated between the installation surface F and the lower surface of the second casing 16.

In the above configuration, when sound is emitted from the speaker 13 by a musical performance operation of the keyboard 12 or the like, as shown in fig. 9A, the sound is emitted in the first direction D1 from the upper surface side of the speaker 13 which is the sound emission surface side. Further, bass sounds resonating in the acoustic space 51 simultaneously with the sound generation are generated from the lower surface of the tapered portion of the speaker 13 through the bass reflex duct 61 and from the sound hole 62 in the second direction D2.

Further, as shown in fig. 11, since the leg 81 is provided on the lower surface of the second casing 16 and a gap is formed between the installation surface F and the lower surface of the second casing 16, sound can be emitted to the outside without blocking the sound hole 62.

According to the above embodiment, as shown in fig. 2B, since the plate member 60 serving as the sound emitting member is provided in the second region S2 corresponding to the back surface of the inner 21, sound can be emitted from the sound holes 62 at positions not overlapping (not corresponding) with the first region S1 corresponding to the back surface of the speaker 13. Accordingly, even if the vertical dimension of the housing 11 is reduced, the distance between the sound hole 62 and the rear surface of the speaker 13 can be increased, and the vertical width of the housing 11 can be reduced and bass sound can be emitted satisfactorily. In this way, in the electronic keyboard instrument 10 according to the above-described embodiment, the miniaturization of the whole electronic keyboard instrument 10 and the improvement of the bass sound quality can be achieved in a trade-off relationship.

Further, by fixing the plate member 60 to the second casing 16, a part of the bass reflex duct 61 can be formed with a simple configuration, and the bass sound quality can be improved.

Further, as shown in fig. 9 and the like, since the bass reflex path 61 is formed also including the inner surface of the base portion 43 of the second enclosure 16, the number of parts for forming the bass reflex path 61 can be suppressed.

In the above embodiment, as shown in fig. 4, the first to third fixing portions 69 to 71 are provided, and the plate member 60 having the first length L1 and the plate member 60A having the second length L2 can be selected and attached to the second housing 16. In other words, by being able to select 2 plate members 60, 60A, the length of the bass reflex duct 61 in the left-right direction can be changed by the first length L1 and the second length L2. This makes it possible to adjust the length of the bass reflex duct 61 in accordance with the performance of the mounted speaker 13, and to improve the bass sound quality.

Further, since the plurality of sound holes 62 are arranged in the right-left and front-rear directions at the bottoms of the plurality of U-shaped grooves 75, the opening area of each sound hole 62 can be reduced. This can prevent large dust from entering the housing 11 from the outside through the sound hole 62.

Further, the plurality of U-shaped grooves 75 extend in the sound emission direction in the acoustic space 51, and thus, the bass sound quality can be improved more effectively.

Further, by providing the reinforcing ribs 77 extending in the left-right direction, the strength in the region where the plurality of sound holes 62 are formed can be improved. Further, the extending direction of the reinforcing rib 77 is along the sound emission direction in the acoustic space 51 similarly to the U-shaped groove 75, and the bass sound quality can be improved more favorably.

Further, since the bass reflex duct 61 including the plate member 60 is provided between the 2 speakers 13, the bass reflex duct 61 can be provided to emit a good bass sound without increasing the width of the cabinet 11 in the right and left direction. Therefore, the bass sound quality can be improved while avoiding an increase in size of the housing 11 by the amount of the bass reflex duct 61.

In addition, according to the above embodiment, since the extension region 24 in which the internal member 21 is disposed outside is formed in the intermediate member 20, the space below the internal member 21 can be enlarged as the acoustic space 51. This makes it possible to form a good acoustic space 51 that is enlarged in the lateral direction while avoiding an increase in the size of the housing 11 in the lateral direction and the front-rear direction. In this way, in the electronic keyboard instrument 10 of the above embodiment, it is possible to achieve both downsizing of the whole electronic keyboard instrument 10 and formation of a good acoustic space 51, which are in a trade-off relationship.

Here, in the above embodiment, the internal member 21 is disposed in the region closer to the center portion in the left-right direction of the entire keyboard 12 than the main region 23, and the internal member 21 can be disposed in the space outside above the extended region 24. Therefore, in the electronic keyboard instrument 10, the extension region 24 can be formed by the space inside the speaker 13 in the left-right direction and below the various internal members 21, and the downsizing of the whole electronic keyboard instrument 10 and the formation of the good acoustic space 51 can be achieved at the same time.

In the above embodiment, in the state shown in fig. 1B before the first casing 15 and the second casing 16 are combined, the intermediate member 20 can be fixed to the second casing 16 to form the acoustic space 51. Therefore, the above embodiment can easily form a good acoustic space 51, compared to a configuration in which the first casing 15 and the second casing 16 are combined to form an acoustic space. In addition, the acoustic test can be performed by forming the acoustic space 51 in a state where the first casing 15 is separated from the second casing 16. This makes it possible to perform adjustment after the acoustic test without attaching or detaching the first casing 15 to or from the second casing 16, and thus to reduce the burden of the adjustment.

Further, since the intermediate member 20 has the sound emission hole 26a at a position corresponding to the speaker 13, sound can be emitted in the first direction D1 from the upper surface of the speaker 13. Here, both the intermediate member 20 and the speaker 13 can have the left-right direction of the sound emission hole 26a as the longitudinal direction, and can contribute to the reduction of the front-rear width of the housing 11.

As shown in fig. 7, the intermediate member 20 has a fixing hole 39, and the fixing hole boss 41 forming the fixing hole 39 is sandwiched between the downward boss 15a of the first housing 15 and the housing fixing boss 46 of the second housing 16 by fastening the screw 52. In other words, the intermediate member 20 can be fixed around the fixing hole 39 by fastening the screw 52 that fixes the first casing 15 and the second casing 16, and the intermediate member 20 can be fixed satisfactorily.

In the intermediate member 20, the main region 23 is formed to have a height greater than that of the extension region 24, so that the extension region 24 can be easily disposed below the internal member 21 while securing a space for accommodating the speaker 13 in the main region 23. This enables a good acoustic space 51 to be formed inside the intermediate member 20.

Further, since the intermediate member 20 has the front wall 27, the rear wall 28, the outer wall 31, and the rib side walls 34, the intermediate member 20 can be formed into a box shape, and the acoustic space 51 having a predetermined volume can be formed by the intermediate member 20. Further, the rigidity of the intermediate member 20 itself can be increased, and the intermediate member 20 also functions as a reinforcing member that reinforces the housing 11.

Further, since the inclined portion 36 is provided at the boundary between the main region 23 and the extension region 24, the acoustic space 51 can be enlarged between the intermediate wall 30 and the upper wall 33 as shown in fig. 9A. The direction of the inclined portion 36 follows the flow of sound shown by the broken line in fig. 9A, and sound in the sound space 51 on the main area 23 side can be favorably transmitted to the extended area 24 side through the inclined portion 36.

Here, in the state shown in fig. 5B, since the mounting hole boss 40 having a semicircular arc-shaped outer peripheral surface at a position overlapping the inclined portion 36 is provided on the inner side, the sound in the sound space 51 on the main area 23 side can be favorably transmitted to the expanded area 24 side by the mounting hole boss 40.

Further, the length of the intermediate member 20 in the front-rear direction is shorter than the length in the left-right direction, and the size of the intermediate member 20 and the electronic keyboard instrument 10 in the front-rear direction as a whole can be made compact.

The present invention is not limited to the above embodiments, and can be implemented with various modifications. In the above-described embodiments, the size, shape, orientation, and the like shown in the drawings are not limited thereto, and can be appropriately changed within a range in which the effects of the present invention are exhibited. The present invention can be implemented with appropriate modifications without departing from the scope of the object of the present invention.

In the above embodiment, the sound emitting means is constituted by the plate members 60 and 60A, but the present invention is not limited thereto, and various modifications can be made as long as at least a part of the bass reflex duct 61 can be constituted.

For example, the bass reflex duct 61 may be formed integrally with the second casing 16, instead of being formed separately, as a sound emitting member of a structural portion corresponding to the plate members 60 and 60A. The bass reflex duct 61 may be configured such that a sound emitting member, which is a structural portion corresponding to the plate members 60 and 60A, is formed integrally with the first casing 15, and may be formed in a duct shape in a state where the first casing 15 and the second casing 16 are combined. The bass reflex duct 61 may be formed by increasing the vertical height of the duct rib 63, omitting the three side walls 66 of the plate members 60 and 60A, and forming a flat plate member as a sound emitting member.

The sound emitting member may be a passive radiator (passive radiator) instead of the bass reflex duct 61. The passive radiator may be provided in the formation region of the sound hole 62 instead of the sound hole 62 in the base portion 43 of the second housing 16. By providing the passive radiator, it is possible to generate sound from the second direction D2 and to more favorably prevent dust from entering from the lower surface side of the second housing 16.

The sound holes 62 are not limited to the size, number of formation, and shape of the above embodiment, and may be changed within a range capable of generating sound in the same manner as described above.

In the above-described embodiment, the example in which the electronic musical instrument is the electronic keyboard musical instrument 10 is shown, but it is not limited thereto. The electronic musical instrument may be any instrument that produces sound by a user's operation, and may be an electric violin, an electric guitar, a drum, a horn, or the like, in addition to other keyboard musical instruments.

Therefore, the "keyboard 12" of the above embodiment may be replaced by strings, valves, other performance operators for pitch designation, arbitrary performance operators, and the like.

In addition, terms described in the present disclosure and/or terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings.

The respective aspects and embodiments described in the present disclosure may be used alone, may be used in combination, or may be switched and used in association with execution.

Any reference to the use of "first," "second," etc. named elements in this disclosure also does not limit the amount or order of such elements in their entirety. These designations may be used in this disclosure as a convenient way to distinguish between 2 or more elements. Thus, reference to a first and second element does not imply that only 2 elements can be used or that the first element must precede the second element in some fashion.