Electronic musical instrument and sound reproduction unit

Abstract

The utility model provides an electronic musical instrument capable of obtaining uniform amplitude frequency characteristics in the horizontal direction. An electronic musical instrument (300) has a sound reproduction unit (400) supported on the rear surface of a top plate (301), and the sound reproduction unit (400) is provided with: a speaker driver holding section (420) that holds a speaker driver (410) that reproduces sound toward the top plate (301); a tapered diffuser (450) having an enlarged cross-sectional area on the opposite side from the tip section, the diffuser (450) having the tip section facing the speaker driver (410) and supported by the speaker driver holding section (420), the diffuser (450) guiding sound waves emitted from the speaker driver (410) in a direction along the back surface of the top plate (301); and an attachment installation part (440) which suspends the speaker driver holding part (420) and is attached to the rear surface of the top plate (301).

Description

Technical Field

[0001] The utility model relates to electronic musical instruments such as keyboard electronic musical instruments and sound-producing units thereof. Background Art

[0002] A speaker such as a dynamic speaker that vibrates a diaphragm has strong directivity in the front direction. Therefore, in electronic musical instruments, a sound emitting unit is used in which a sound emission control device called a diffuser is arranged in front of the speaker. For example, in Patent Document 1, a sound emitting unit having a conical diffuser with the front end facing the diaphragm is arranged on the left and right sides of the keyboard of a keyboard electronic musical instrument.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-178336 Utility Model Content

[0006] Technical problems to be solved by utility models

[0007] In the technology disclosed in Patent Document 1, since the sound emitting unit having a diffuser is arranged at the height of the keyboard of the keyboard electronic musical instrument, there is a problem that a uniform amplitude-frequency characteristic cannot be obtained in the horizontal direction at the height of the player's head, and the sound quality changes when the player moves his head.

[0008] The present utility model is made in view of the above situation, and its purpose is to provide an electronic musical instrument that can obtain uniform amplitude-frequency characteristics in the horizontal direction.

[0009] Technical solutions for solving technical problems

[0010] The utility model provides an electronic musical instrument, which has a sound-emitting unit supported on the back side of a top plate, and the sound-emitting unit includes: a speaker driver holding portion, which holds the speaker driver that emits sound toward the top plate; a conical diffuser with a cross-sectional area enlarged on the opposite side compared to a front end portion, which makes the front end portion face the speaker driver and is supported by the speaker driver holding portion, and guides the sound waves emitted from the speaker driver in the direction along the back side of the top plate; and an installation portion, which suspends the speaker driver holding portion and is installed on the back side of the top plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 1 is a perspective view showing the structure of a keyboard electronic musical instrument 300 as one embodiment of the present invention.

[0012] Figure 2It is a perspective view showing the structure of the sound emitting unit 400 in this embodiment.

[0013] Figure 3 yes Figure 2 Ia-Ib line cross-sectional view.

[0014] Description of Reference Numerals

[0015] 300 ... keyboard electronic musical instrument, 301 ... top plate, 400 ... sound emitting unit, 410 ... speaker driver, 420 ... speaker driver holding portion, 430 ... speaker box, 440 ... mounting portion, 450 ... diffuser, 451 ... front end portion, 452 ... base end portion, 421 ... opening, 453 ... foot, 433 ... cylindrical portion, 434 ... bolt, 431 ... upper plate portion, 432 ... accommodation portion, 437 ... port, 411 ... magnetic circuit, 411a ... yoke, 411b ... pole piece, 411c ... magnet, 411d ... plate, G ... magnetic gap, 414 ... cone, 412 ... voice coil bobbin, 412a ... voice coil, 416 ... support portion. DETAILED DESCRIPTION

[0016] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0017] Figure 1 1 is a perspective view showing the structure of a keyboard electronic musical instrument 300 as one embodiment of the present invention. Figure 2 : is a perspective view showing the structure of the sound emitting unit 400 in this embodiment. Figure 3 yes Figure 2 Ia-Ib line cross-sectional view. Below, the structure of this embodiment is described by assuming an orthogonal coordinate system consisting of mutually orthogonal X-axis, Y-axis and Z-axis. The Z-axis is an axis in the vertical direction. The sound-releasing axis of the speaker driver 410 in the sound-releasing unit 400 is an axis parallel to the Z-axis. The X-axis is an axis in the left-right direction of the keyboard electronic musical instrument 300. The Y-axis is an axis in the front-back direction of the keyboard electronic musical instrument 300. It should be noted that in the following, Figure 1 The left side of the keyboard electronic musical instrument 300 is called the +X side, the right side is called the -X side, the front side is called the +Y side, the rear side is called the -Y side, the upper side is called the +Z side, and the lower side is called the -Z side.

[0018] Like a common keyboard electronic musical instrument, the keyboard electronic musical instrument 300 has a top plate 301 parallel to the XY plane on its housing. The sound emitting unit 400 in this embodiment is supported so as to be suspended on the back surface, i.e., the -Z side surface, of the top plate 301. The position of the top plate 301 in the Z direction substantially coincides with the position of the head of the player of the keyboard electronic musical instrument 300.

[0019] The sound emitting unit 400 has a plate-shaped speaker driver holding portion 420 parallel to the XY plane. The speaker driver holding portion 420 is a member that holds the speaker driver 410 that emits sound toward the +Z side, that is, toward the top plate 301 .

[0020] like Figure 3 As shown, the speaker driver 410 has a magnetic circuit 411 , a voice coil bobbin 412 , a dust cover 413 , a cone 414 , an edge 415 , and a support portion 416 .

[0021] The magnetic circuit 411 includes a circular yoke 411a parallel to the XY plane, a cylindrical pole piece 411b protruding from the central area of ​​the yoke 411a to the +Z side, an annular magnet 411c surrounding the pole piece 411b on the +Z side of the yoke 411a, and an annular plate 411d surrounding the pole piece 411b on the +Z side of the magnet 411c. A magnetic field due to the magnet 411c is generated in a magnetic gap G sandwiched between the inner side surface of the plate 411d and the outer side surface of the pole piece 411b.

[0022] The edge 415 is a roughly annular elastic member. A circular opening 421 having its center on the sound emission axis of the speaker driver 410 is formed on the speaker driver retaining portion 420, and the outer edge of the edge 415 is fixed to the inner edge of the opening 421. The cone 414 is a cone having a large diameter opening on the +Z side and a small diameter opening on the -Z side. The small diameter opening on the -Z side of the cone 414 is connected to the outer peripheral surface of the cylindrical voice coil bobbin 412. A voice coil 412a is wound around the voice coil bobbin 412. The voice coil bobbin 412 inserts the voice coil 412a into the magnetic gap G and is supported by the cone 414. The dust cover 413 is a dome-shaped member protruding toward the +Z side, and covers the voice coil bobbin 412 from the +Z side. The large-diameter opening on the +Z side of the cone 414 is connected to the inner edge of the edge 415 , and the outer edge of the edge 415 is connected to the opening 421 of the speaker driver holding portion 420 .

[0023] The support part 416 is a cone-shaped member having a small-diameter opening on the -Z side and a large-diameter opening on the +Z side. The small-diameter opening on the -Z side of the support part 416 is connected to the plate 411d, and the large-diameter opening on the +Z side is connected to the edge of the circular opening 421 surrounding the speaker driver holding part 420.

[0024] The mounting part 440 is a cylindrical member protruding from the four corners of the quadrilateral speaker driver holding part 420 to the +Z side. The end surfaces of the four cylindrical mounting parts 440 on the +Z side are mounted on the back side of the top plate 301 to suspend the speaker driver holding part 420. The mounting part 440 can be mounted on the back side of the top plate 301 by adhesive or bolts.

[0025] The diffuser 450 is a conical component, and the front end portion 451 is opposed to the speaker driver 410 and supported by the speaker driver holding portion 420. Specifically, the diffuser 450 is a conical component, and the opposite side of the front end portion 451 in the Z-axis direction is a circular base end portion 452 with an expanded cross-sectional area. The front end portion 451 of the diffuser 450 is located on the sound emission axis of the speaker driver 410 (specifically, the Z axis passing through the center in the XY plane of the speaker driver 410). The base end portion 452 of the diffuser 450 is a first circle having a center on the sound emission axis of the speaker driver 410. Four parts around the base end portion 452 are connected to the speaker driver holding portion 420 via four legs 453 and supported by the speaker driver holding portion 420. As described above, the speaker driver holding portion 420 holds the speaker driver 410 in a circular opening 421 (for example, set as a second circle), and the circular opening 421 has a center on the sound emission axis of the speaker driver 410. Therefore, in the present embodiment, the speaker driver holding portion 420 holds the speaker driver 410 in the opening 421 forming a second circle that is concentric with the first circle. Furthermore, the diffuser 450 diffuses the sound waves emitted from the speaker driver 410 in the Z direction in all directions within the XY plane. Therefore, in the housing of the keyboard electronic musical instrument 300, a horizontal slit opening toward the player side (+Y side) can be provided at the same height as the back surface of the top plate 301, i.e., the surface on the -Z side.

[0026] In the speaker driver holding part 420, the speaker box 430 is mounted on the opposite side of the diffuser 450. More specifically, on the surface of the speaker driver holding part 420 on the -Z side, the upper surface part 431 of the speaker box 430 is mounted.

[0027] The speaker driver holder 420 and the upper surface 431 of the speaker box 430 have the same quadrilateral shape when viewed from the +Z side. In addition, the speaker box 430 has a substantially rectangular shaped accommodating portion 432, which has a quadrilateral opening on the +Z side that is accommodated inside the four sides of the upper surface 431. A port 437 is provided at the center of the bottom of the accommodating portion 432. In addition, the upper surface 431 is provided with cylindrical portions 433 that protrude toward the -Z side from four corners and four central portions of the four sides. Moreover, the speaker box 430 is fixed to the speaker driver holder 420 by eight bolts 434 that penetrate the speaker driver holder 420 and reach the eight cylindrical portions 433. The speaker driver 410 is accommodated in a space formed by the speaker driver holder 420 and the speaker box 430.

[0028] In the present embodiment, the height (position in the Z-axis direction) of the top portion of the mounting portion 440 is substantially the same as the height of the base end portion 452 of the diffuser 450 .

[0029] According to the present embodiment, when the voice coil 412a is energized, the voice coil bobbin 412 and the cone 414 vibrate in the Z-axis direction, and the sound wave is emitted in the +Z direction. When the sound wave reaches the back of the top plate 301, it is diffused radially and propagates along the back of the top plate 301. Therefore, a uniform amplitude-frequency characteristic is obtained in the horizontal plane at the height of the head of the player playing the keyboard electronic musical instrument 300, mainly in the low and medium range. Therefore, it is possible to avoid changes in the sound quality when the player moves his head. In addition, in the present embodiment, the sound is emitted in 360° directions including the +X direction, the +Y direction, the -X direction, and the -Y direction. Therefore, the listener can feel an extended reverberation. In addition, according to the present embodiment, since the diffusion of the sound wave is performed by the diffuser 450, a uniform amplitude-frequency characteristic can be obtained in the horizontal plane even for the high range.

[0030] Although one embodiment of the present invention has been described above, the present invention may also have other embodiments. For example, the following are described.

[0031] (1) The number and position of the sound emitting unit 400 are arbitrary. One sound emitting unit 400 may be installed at the center of the back side of the top plate 301 , or two sound emitting units 400 may be installed at the left and right sides of the top plate 301 .

[0032] (2) Since the sound emitting unit 400 can be easily mounted on the keyboard electronic musical instrument 300 , it can be manufactured and sold independently of the keyboard electronic musical instrument 300 .

Claims

1. An electronic musical instrument, characterized in that: A sound-emitting unit is supported on the back of the top plate. The sound emitting unit comprises: a speaker driver holding portion that holds a speaker driver that emits sound toward the top plate; A conical diffuser having a larger cross-sectional area on the opposite side than the front end, wherein the front end is opposed to the speaker driver and supported by the speaker driver holding portion, and guides the sound waves emitted from the speaker driver in a direction along the back side of the top plate; The installation part suspends the speaker driver holding part and is installed on the back side of the top plate.

2. The electronic musical instrument according to claim 1, wherein: The height of the top portion of the mounting portion is substantially the same as the height of the base end portion of the diffuser.

3. The electronic musical instrument according to claim 1, wherein: The diffuser has a conical shape whose cross-sectional shape at a base end portion is a first circle, and the speaker driver holding portion holds the speaker driver in an opening forming a second circle that is concentric with the first circle.

4. The electronic musical instrument according to claim 1, wherein: There is a speaker box disposed on an opposite side of the diffuser in the speaker driver retaining portion.

5. A sound-emitting unit, characterized in that: have: a speaker driver holding portion that holds a speaker driver; A conical diffuser having a larger cross-sectional area on the opposite side than the front end, wherein the front end is opposed to the speaker driver and supported by the speaker driver holding portion, and guides the sound waves emitted from the speaker driver in a direction away from the sound emission axis of the speaker driver; The installation part suspends the speaker driver holding part and installs it on other components above.

6. The sound reproduction unit according to claim 5, characterized in that: The height of the top portion of the mounting portion is substantially the same as the height of the base end portion of the diffuser.

7. The sound reproduction unit according to claim 5, characterized in that: The diffuser has a conical shape whose cross-sectional shape at a base end portion is a first circle, and the speaker driver holding portion holds the speaker driver in an opening forming a second circle that is concentric with the first circle.

8. The sound reproduction unit according to claim 5, wherein: There is a speaker box disposed on an opposite side of the diffuser in the speaker driver retaining portion.

Images