Sound diffuser, electronic musical instrument having the same, keyboard electronic musical instrument, and diffusion method

Abstract

The present application provides a diffuser capable of widening directivity without distorting sound when applied to a full-range speaker. A diffuser (1) as a diffuser has a first annular control portion (10), a second annular control portion (20), and a third annular control portion (30). The first annular control portion (10) has a first communication hole (11) and an annular inclined plate (12) surrounding the first communication hole (11) and inclined with respect to the axial direction of the first communication hole (11). The second annular control portion (20) has a second communication hole (21) coaxial with the first communication hole (11) and an annular inclined plate (22) surrounding the second communication hole (21) and housing the first annular control portion (10) inside. The third annular control portion (30) has a plurality of third communication holes (31) and surrounds the second annular control portion (20).

Description

Technical Field

[0001] The present invention relates to a diffuser for widening the directivity of a loudspeaker system, an electronic musical instrument having the diffuser, a keyboard electronic musical instrument, and a diffusion method. Background Technology

[0002] As a technique for widening the directivity of a loudspeaker system, there is the technology disclosed in Patent Document 1. In the technology disclosed in Patent Document 1, the sound from the loudspeaker unit is concentrated into a small hole and narrowed, and a droplet-shaped diffuser (diffuser) provided in the hole diffuses the sound and widens the directivity.

[0003] Patent Document 1: Japanese Patent No. 3818959

[0004] However, in the technology disclosed in Patent Document 1, in order to effectively narrow the sound, a grille with multiple holes is not provided around the narrowing hole. When such technology is applied to a full-range loudspeaker, air may be trapped in the space between the diffuser and the loudspeaker unit, causing sound distortion due to deformation of the loudspeaker unit. Summary of the Invention

[0005] The present invention was proposed to solve the above-mentioned problems. Its purpose is to provide a technical means to widen the directivity without causing sound distortion when applied to a full-range loudspeaker.

[0006] The present invention provides a sound diffuser having a first annular control portion, a second annular control portion, and a third annular control portion. The first annular control portion has a first communicating hole and an annular inclined plate that surrounds the first communicating hole and is inclined relative to the axial direction of the first communicating hole. The second annular control portion has a second communicating hole and an annular inclined plate that surrounds the second communicating hole and houses the first annular control portion inside it, and is inclined relative to the axial direction of the second communicating hole. The third annular control portion has a plurality of third communicating holes that surround the second annular control portion. Attached Figure Description

[0007] Figure 1 This is a top view showing the structure of a diffuser as an embodiment of the sound diffuser involved in the present invention.

[0008] Figure 2 yes Figure 1 Sectional view along line I-I'.

[0009] Figure 3 This is a diagram illustrating an application example of this implementation method. Detailed Implementation

[0010] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0011] Figure 1 This is a top view showing the structure of a diffuser 1, which is an embodiment of the sound diffuser involved in this invention. Figure 2 yes Figure 1 A sectional view along line I-I'. Furthermore, in Figure 2 In order to make it easier to understand the usage of the diffuser 1, the speaker unit 2 and the diffuser 1 are shown together.

[0012] like Figure 1 and Figure 2 As shown, the diffuser 1 has a first annular control section 10, a second annular control section 20, a third annular control section 30, and support sections 41 to 44.

[0013] The first annular control section 10 is a funnel-shaped component with a first connecting hole 11 in its center and an annular inclined plate 12 surrounding the first connecting hole 11 and inclined relative to the axial direction of the first connecting hole 11. When the diffuser 1 is installed on the speaker unit 2, the axis of the first connecting hole 11 is aligned with the central axis O of the speaker unit 2.

[0014] The second annular control section 20 is a funnel-shaped component with a second connecting hole 21 coaxial with the first connecting hole 11 in the center. It has an annular inclined plate 22 that surrounds the second connecting hole 21 and houses the first annular control section 10 inside, and is inclined relative to the axial direction of the second connecting hole 21.

[0015] In the illustrated example, the inclined plate 12 of the first annular control unit 10 is connected to the inclined plate 22 of the second annular control unit 20 via four support plates 13 extending radially from the inclined plate 12, and is supported by the inclined plate 22. Alternatively, the inclined plate 12 of the first annular control unit 10 can be connected to the second annular control unit 20 via at least one support plate 13 extending radially between the inclined plate 12 of the first annular control unit 10 and the inclined plate 22 of the second annular control unit 20.

[0016] Moreover, in this embodiment, such as Figure 2 As shown, as the axis from the first connecting hole 11 and the second connecting hole 21, i.e. the central axis O of the speaker unit 2, moves away, the cross-sectional area of ​​the space between the inclined plate 12 of the first annular control section 10 and the inclined plate 22 of the second annular control section 20 increases.

[0017] In addition, in this embodiment, such as Figure 2As shown, for the second annular control unit 20, the thickness of the inclined plate 22 increases as it moves away from the axis of the first connecting hole 11 and the second connecting hole 21, i.e., the central axis O of the speaker unit 2.

[0018] The third annular control section 30, equivalent to a grille, has multiple third connecting holes 31 and surrounds the second annular control section 20. In the illustrated example, the third annular control section 30 is composed of multiple concentric horizontal baffles 32 and multiple ribs 33 extending radially outward from the center of the diffuser 1. The multiple third connecting holes 31 form generally rectangular connecting holes surrounded by the horizontal baffles 32 and the ribs 33. Further, as... Figure 1 and Figure 2 As shown, the third connecting hole 31 of the third annular control unit 30 is disposed in a region that does not overlap with the inclined plate 22 of the second annular control unit 20 when viewed from the axial direction of the second connecting hole 21.

[0019] Support portions 41 to 44 are provided at four locations around the diffuser 1. Through holes 41a to 44a are provided in the support portions 41 to 44. Screws are inserted into the through holes 41a to 44a and screwed into the internal threaded holes provided in the baffle (not shown) on which the speaker unit 2 is mounted, thereby fixing the diffuser 1 to the speaker unit 2.

[0020] In this embodiment, the sound emitted from the speaker unit 2 travels through the first communication hole 11 of the first annular control section 10 of the diffuser 1, and is guided in the space between the inclined plate 12 of the first annular control section 10 and the inclined plate 22 of the second annular control section 20, thereby widening the directivity and emitting sound to the outside of the diffuser 1. Furthermore, the sound emitted from the speaker unit 2 is emitted to the outside of the diffuser 1 through a plurality of third communication holes 31 provided in the third annular control section 30.

[0021] In this embodiment, unlike the technology in Patent Document 1 described above, the sound is not narrowed; instead, the directivity is widened by transmitting sound along the surfaces of the inclined plates 12 and 22. Therefore, according to this embodiment, when the diffuser 1 is applied to a full-range loudspeaker, sound distortion is not produced, and the directivity is widened.

[0022] Furthermore, according to this embodiment, as the distance from the central axis O increases, the cross-sectional area of ​​the space between the inclined plate 12 of the first annular control unit 10 and the inclined plate 22 of the second annular control unit 20 expands, thus sound can easily pass through the space between the inclined plates 12 and 22, and the effect of widening the directivity is enhanced.

[0023] Furthermore, according to this embodiment, for the second annular control unit 20, the thickness of the tilt plate 22 increases as it moves away from the central axis O of the speaker unit 2, resulting in the following effects. First, near the central axis O, the tilt plate 22 is thinner, thus making it easier to guide the sound emitted from the speaker unit 2 within the space between the tilt plates 12 and 22. Second, away from the central axis O, the tilt plate 22 is thicker, thus increasing the mechanical strength of the tilt plate 22 that supports the tilt plate 12.

[0024] Figure 3 This diagram illustrates an application example of this embodiment. In this example, a speaker unit 2 is disposed on the upper surface of a shelf supporting the keys in a keyboard electronic instrument 3 installed on the floor 4. The speaker unit 2 has its sound-emitting surface facing downwards, and a diffuser 1 covers the sound-emitting surface of the speaker unit 2. If a performer U1, seated in front of the keyboard electronic instrument 3, plays the keyboard electronic instrument 3, the speaker unit 1 emits sound downwards in accordance with the performance. Furthermore, in this example, an audience member U2, standing at a separate position behind the performer U1, listens to the keyboard performance by the performer U1.

[0025] exist Figure 3 In this system, the sound heard by performer U1 is emitted by speaker unit 2, and the sound reflected from floor 4 to reach performer U1 is dominant. Assuming there is no diffuser 1, the sound reflected from floor 4 has narrow directivity, therefore the frequency response of the sound heard by performer U1 is prone to peak dip due to interference from structures (e.g., floor 4, keyboard / electronic instrument 3). Furthermore, for listener U2 standing far from speaker unit 2, there is a problem that the high-frequency sounds, especially those emitted by speaker unit 2, are difficult to reach.

[0026] However, in this application example, the sound-emitting surface of the speaker unit 2 is covered by the diffuser 1. Therefore, the sound emitted from the speaker unit 1 passes through the diffuser 1, thus becoming a directionally broadened sound S1 directed towards the floor 4. Moreover, the sound S1 is reflected at the floor 4, becoming a directionally broadened sound S2, and is emitted into the entire spatial area containing the performer U1's body. Therefore, the aforementioned problems are solved.

[0027] The inventors of this application have confirmed through experiments that by providing a diffuser 1 on the front surface of the speaker unit 2, the directivity of the sound emitted from the speaker unit 2 is widened. Specifically, it was confirmed that the sound pressure level in the direction of ±90 degrees relative to the drive axis of the speaker unit 2 increases from -12dB to 0dB at 1kHz and from -20dB to -5dB at 2kHz. Furthermore, it was confirmed that the sound pressure level in the direction of ±45 degrees relative to the drive axis of the speaker unit 2 increases from -30dB to -2dB at 2kHz and from -30dB to -9dB at 4kHz. Additionally, it was confirmed that without the diffuser 1, a large tilt angle occurs in the frequency response of the sound heard by the performer U1 at 3kHz, but this large tilt angle is improved with the diffuser 1. It was also confirmed that without the diffuser 1, a large tilt angle also occurs in the frequency response of the sound heard by the listener U2 at 3kHz, but this large tilt angle is improved with the diffuser 1.

[0028] <Other Implementation Methods>

[0029] The above description illustrates one embodiment of the present invention, but other embodiments are conceived for the present invention. For example, as described below.

[0030] (1) In the above embodiment, the annular inclined plates 12 and 22 are funnel-shaped inclined plates, but inclined plates with a truncated cone side shape can also be used.

[0031] (2) In the above embodiment, the two inclined plates are tilted such that, as they move toward the sound emission direction of the speaker unit 2, the cross-sectional area of ​​the space inside the inclined plate 12 of the first annular control unit 10 and the cross-sectional area of ​​the space inside the inclined plate 22 of the second annular control unit 20 increases. However, alternatively, the two inclined plates may be tilted such that, as they move toward the sound emission direction of the speaker unit 2, the cross-sectional area of ​​the space inside the inclined plate 12 of the first annular control unit 10 and the cross-sectional area of ​​the space inside the inclined plate 22 of the second annular control unit 20 decreases.

[0032] (3) In the above embodiment, two inclined plates, consisting of the inclined plate 12 of the first annular control unit 10 and the inclined plate 22 of the second annular control unit 20, are disposed on the diffuser 1, but more inclined plates may also be disposed on the diffuser 1.

[0033] (4) For the first annular control unit 10, the thickness of the tilting plate 12 can be increased as it travels toward the sound emission direction of the speaker unit 2. In this case, the thicker part is supported by the support plate 13. In this way, the mechanical strength of the first annular control unit 10 and the support plate 13 is increased.

[0034] (5) Alternatively, the tilt angle of the tilt plate 22 of the second annular control unit 20 relative to the direction of sound emission of the diffuser 1, i.e., the direction of the central axis O of the speaker unit 2, can be greater than the tilt angle of the tilt plate 12 of the first annular control unit 10 relative to that direction. In this case, as the sound emission direction is traveled, the cross-sectional area of ​​the space between the tilt plate 12 of the first annular control unit 10 and the tilt plate 22 of the second annular control unit 20 increases, so sound can pass through more easily, and the effect of widening the directivity is enhanced.

[0035] (6) The four support plates 13 supporting the first annular control section 10 are supported by the second annular control section 20, but may also be supported by the third annular control section 30. In this case, the support plates 13 are supported by the crossbar member 32, or rib 33, or both of the above, which constitute the third annular control section 30.

[0036] (7) In the above embodiment, the drive shaft of the speaker unit 2, the shaft of the first connecting hole 11, and the shaft of the second connecting hole 21 are coaxial. However, from the viewpoint of directional control, they do not necessarily have to be coaxial. For example, the shaft of the first connecting hole 11 may be inclined from the drive shaft of the speaker unit 2, for example in... Figure 3 The structure is tilted in the direction of the foot of the axial player U1 in the first connecting hole 11. In this way, it is expected that the directionality will be further widened.

[0037] (8) In the above embodiment, the present invention is implemented as a diffuser 1 that integrates the first annular control unit 10, the second annular control unit 20, and the third annular control unit 30. However, the embodiments of the present invention are not limited thereto. The present invention can also be implemented as a sound diffusion method in which the first annular control unit, the second annular control unit, and the third annular control unit are disposed on the front surface of the sound-emitting surface of the speaker unit to widen the directivity of the sound emitted from the speaker unit. The first annular control unit has: a first connecting hole; and an annular inclined plate that surrounds the first connecting hole and is inclined relative to the axial direction of the first connecting hole. The second annular control unit has: a second connecting hole; and an annular inclined plate that surrounds the second connecting hole and houses the first annular control unit inside, and is inclined relative to the axial direction of the second connecting hole. The third annular control unit has a plurality of third connecting holes that surround the second annular control unit.

[0038] Explanation of the label

[0039] 1…Diffuser, 10…First annular control section, 11…First connecting hole, 12, 22…Inclined plate, 13…Support plate, 20…Second annular control section, 21…Second connecting hole, 30…Third annular control section, 31…Third connecting hole, 32…Horizontal baffle component, 33…Rib, 41~44…Support section, 41a~44a…Through hole, 2…Speaker unit, 3…Keyboard electronic musical instrument, 4…Floor, U1…Performer, U2…Listener.

Claims

1. A sound diffuser, comprising a first annular control section, a second annular control section, and a third annular control section. The first annular control unit has: a first communicating hole; and an annular inclined plate that surrounds the first communicating hole and is inclined relative to the axial direction of the first communicating hole. The second annular control portion has: a second communicating hole; and an annular inclined plate that surrounds the second communicating hole and houses the first annular control portion inside, and is inclined relative to the axial direction of the second communicating hole. The third annular control section has multiple third connecting holes, which surround the second annular control section. The third connecting hole of the third annular control unit is disposed in a region that does not overlap with the inclined plate of the second annular control unit when viewed axially from the second connecting hole. The axial direction of the third connecting hole is consistent with the central axis of the speaker unit. In the third annular control section, the inner end of the crossbar member and rib that constitute the third connecting hole, which is perpendicular to the axial direction of the third connecting hole, and the inner end of the inclined plate of the second annular control section, which is perpendicular to the axial direction of the second connecting hole, are on different planes.

2. The sound diffuser according to claim 1, wherein, The second connecting hole is coaxial with the first connecting hole.

3. The sound diffuser according to claim 1 or 2, wherein, As the axis moves away from the second connecting hole, the cross-sectional area of ​​the space between the inclined plate of the first annular control unit and the inclined plate of the second annular control unit increases.

4. The sound diffuser according to claim 1 or 2, wherein, The thickness of the inclined plate of the second annular control section increases as it moves away from the axis of the second connecting hole.

5. The sound diffuser according to claim 1 or 2, wherein, The thickness of the inclined plate of the first annular control section increases as it moves away from the axis of the first connecting hole.

6. The sound diffuser according to claim 1 or 2, wherein, The tilting degree of the tilting plate of the second annular control unit relative to the sound emission direction of the diffuser is greater than the tilting degree of the tilting plate of the first annular control unit relative to the sound emission direction of the diffuser.

7. The sound diffuser according to claim 1, wherein, The first annular control unit is connected to the second annular control unit via at least one support plate extending radially between the inclined plate of the first annular control unit and the inclined plate of the second annular control unit.

8. The sound diffuser according to claim 1, wherein, The third annular control section forms a speaker grille.

9. An electronic musical instrument having a sound diffuser according to any one of claims 1 to 8.

10. A keyboard electronic musical instrument having a sound diffuser according to any one of claims 1 to 8.

11. A method for sound diffusion, wherein, The first, second, and third annular control units are positioned on the front surface of the speaker unit's sound-emitting surface to widen the directivity of the sound emitted from the speaker unit. The first annular control unit has: a first communicating hole; and an annular inclined plate that surrounds the first communicating hole and is inclined relative to the axial direction of the first communicating hole. The second annular control portion has: a second communicating hole; and an annular inclined plate that surrounds the second communicating hole and houses the first annular control portion inside, and is inclined relative to the axial direction of the second communicating hole. The third annular control section has multiple third connecting holes, which surround the second annular control section. The third connecting hole of the third annular control unit is disposed in a region that does not overlap with the inclined plate of the second annular control unit when viewed axially from the second connecting hole. The axial direction of the third connecting hole is consistent with the central axis of the speaker unit. In the third annular control section, the inner end of the crossbar member and rib that constitute the third connecting hole, which is perpendicular to the axial direction of the third connecting hole, and the inner end of the inclined plate of the second annular control section, which is perpendicular to the axial direction of the second connecting hole, are on different planes.

12. The sound diffusion method according to claim 11, wherein, The second connecting hole is coaxial with the first connecting hole.

13. The sound diffusion method according to claim 11 or 12, wherein, As the axis moves away from the second connecting hole, the cross-sectional area of ​​the space between the inclined plate of the first annular control unit and the inclined plate of the second annular control unit increases.

14. The sound diffusion method according to claim 11 or 12, wherein, The thickness of the inclined plate of the second annular control section increases as it moves away from the axis of the second connecting hole.

15. The sound diffusion method according to claim 11 or 12, wherein, The thickness of the inclined plate of the first annular control section increases as it moves away from the axis of the first connecting hole.

16. The sound diffusion method according to claim 11 or 12, wherein, The degree of inclination of the tilt plate of the second annular control unit relative to the direction of the central axis of the speaker unit is greater than the degree of inclination of the tilt plate of the first annular control unit relative to the direction of the central axis of the speaker unit.

17. The sound diffusion method according to claim 11, wherein, The first annular control unit is connected to the second annular control unit via at least one support plate extending radially between the inclined plate of the first annular control unit and the inclined plate of the second annular control unit.

18. The sound diffusion method according to claim 11, wherein, The third annular control section forms a speaker grille.

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