WO2005089013A1

WO2005089013A1 - Speaker

Info

Publication number: WO2005089013A1
Application number: PCT/JP2005/004320
Authority: WO
Inventors: Hiroshi China
Original assignee: Hiroshi China
Priority date: 2004-03-12
Filing date: 2005-03-11
Publication date: 2005-09-22
Also published as: JP2005260627A

Abstract

[PROBLEMS] To provide a speaker capable of preventing its characteristics from being deteriorated by resonance at a specified frequency determined by the length of a pipe even if a pipe type casing is used and capable of reducing its installation floor area and increasing the degree of freedom of design by adopting the pipe type casing. [MEANS FOR SOLVING PROBLEMS] In this speaker, a speaker unit (2) of a diameter roughly equal to the cylindrical diameter of the casing (1) is outwardly and sealingly fitted to one end part of the cylindrical casing (1). The casing (1) is erected with the speaker unit (2) facing upward. A floor board (9) is installed at the bottom part of the casing (1) so that a clearance (an opening part (10)) can be formed between the bottom part and the casing (1). A sound absorbing material (8) is installed on the inner surface of the casing (1).

Description

Specification

Speaker

Technical field

[0001] The present invention relates to a speaker having excellent sound quality and high strength in terms of the design of a housing.

Background art

[0002] Speakers have various configurations such as a flat baffle type, a bass reflex type, a closed type, a horn type, and a knock road horn type depending on a combination of a speaker unit and an enclosure.

[0003] Since the sound quality of these speakers is greatly affected not only by the speaker unit but also by the shape and structure of the enclosure, there are various restrictions on the design of the housing of the speaker as the enclosure.

[0004] For example, in a back-horn type speaker which can be reproduced to a low frequency range using a relatively small speaker unit, a housing is required to obtain the same operation as a necessary horn behind the speaker unit. It becomes complicated, huge, and has design constraints

[0005] Here, the present inventor has created a back-loaded horn type speaker having excellent sound quality and design by producing the same effect as a flared horn by reciprocating the sound inside the case as a tower type. It has already been proposed (see Patent Document 1).

[0006] By the way, there is no proposal for a full-range speaker other than a knock road horn type having a case in which the internal space of the housing is formed into a divergent tubular shape due to the design intention, in which the internal space of the case is cylindrical. .

[0007] This is because sound resonance (resonance) occurs at a specific frequency determined by the length of the tube inside the tubular tube, and in musical instruments such as pipe organs and flutes, these resonances are used. This is because in a full-range loudspeaker for producing various frequencies, resonance at a specific frequency deteriorates characteristics.

[0008] The resonance frequency f is as follows.

f = nc / 2L (Hz) (n: positive integer, c: speed of sound, L: length of tube) [0009] On the other hand, there has been proposed a dedicated speaker (super woofer) for only the low frequency range that uses the above-described resonance to produce a low-pitched sound with a large sound pressure level by resonance in the low frequency range. (For example, see Patent Document 2).

Patent Document 1: JP 2002-10383 A (Page 1, Page 2, FIG. 1, FIG. 2)

Patent Document 2: U.S. Pat.No. 4,628,528 (FIG. 1, FIG. 8)

Disclosure of the invention

Problems to be solved by the invention

[0010] As described above, since the enclosure of the speaker affects the sound characteristics, the shape of the speaker is determined to some extent if sound quality is pursued. The housing of the speaker tended to be large.

[0011] By the way, speakers 1 are installed not only in movie theaters and audio rooms, but also in various places such as coffee shops, live band shops, museums, art galleries, open spaces, and living rooms of ordinary households. In many cases, there are restrictions or limitations on the space in which speakers can be installed, and the shape and size of the speaker housing to be installed are often given priority over the sound quality of the speakers.

[0012] In order to attract customers in stores or to pursue their own hobbies, there is a demand for a speaker having as good a sound quality as possible.

[0013] Therefore, an object of the present invention is to prevent deterioration of characteristics due to sound resonance even when a pipe-type housing is used, and to reduce the installation floor area by using a pipe-type housing. It is an object of the present invention to provide a speaker with a higher degree of freedom in design.

Means for solving the problem

[0014] In order to solve the above-mentioned problem, the invention of claim 1 attaches a speaker unit having a diameter substantially equal to the cylindrical diameter of the cylindrical housing to one end of the cylindrical housing. This is a speaker that is closed off and provided with a sound absorbing material on the inner surface of the housing.

[0015] In a musical instrument having a cylindrical housing such as a Neuve organ or a flute, air freely oscillates in the tube, so that sound resonance (resonance) occurs at various frequencies depending on the length of the cylindrical tube. It was thought that the characteristics of a speaker using a cylindrical housing would also be degraded due to the resonance generated inside the cylinder.However, the thickness of the speaker unit was just above the limit. When driven in a pipe-shaped casing, good characteristics and speakers were obtained.

[0016] This is based on the conventional measurement of characteristics by placing a speaker inside a cylindrical housing, as shown in FIG.

As shown in Fig. A), the diameter of the cylindrical housing 1 and the diameter of the speaker unit 2 are too different from each other, so that the sound spreads inside as a spherical wave 3 and the air freely oscillates. Five (

As shown in B), the speaker unit 2 with a diameter approximately equal to the cylindrical diameter of the housing 1 is installed outward and sealed, so the air inside the cylindrical housing 1 is forced by the speaker unit 2. Air is lost and there is no escape space, and the load is sufficiently applied.In addition, the sound absorbing material provided on the inner surface of the housing eliminates the sound reflected on the inner surface, so that the sound is generated by a plane wave inside the cylindrical housing. As a result, it reaches the end of the cylindrical body, and it is thought that resonance is unlikely to occur by efficiently driving the air.

That is, in a conventional speaker having a cylindrical housing, the piston (speaker) is too small with respect to the cylinder (cylindrical housing), and the internal air cannot be sufficiently powered. In this case, air can be sufficiently controlled as if the piston and cylinder had the same area, and sound was transmitted as a plane wave without the influence of resonance, etc., using the same principle as a syringe.

[0018] Further, the invention of claim 2 is the speaker according to claim 1, wherein the housing is erected with the speaker side facing upward, and a gap is provided between the lower end of the housing and the housing. The bottom plate is provided in such a manner as to provide an omnidirectional speaker, and a substantially conical reflector is provided at the upper end so that the tip of the cone faces the speaker.

[0019] According to the above configuration, the middle sound and the high sound emitted from the front side of the speaker become spherical waves, and the sound is diffused in all directions by the conical reflector provided in front, and the low sound is the sound behind the speaker. Is efficiently driven as a plane wave in a cylindrical housing and diffused in all directions from the gap with the bottom plate at the lower end, so that one speaker unit can be used as one omnidirectional speaker.

[0020] Further, the invention according to claim 3 is the speaker according to claim 1 or 2, wherein the speaker unit is provided with an extension extending beyond the edge portion of the cone paper so that the effective straightness of the cone paper is improved. It employs a configuration using speakers with a larger diameter.

[0021] Usually, the periphery of the speaker unit is a frame connected to the enclosure. The boundary between the frame and the vibrating paper (cone paper) is made of a ring-shaped soft material called an edge, which is smaller than the outer diameter of the speaker unit by the size of the edge, which is smaller than that of the speaker unit. By providing an extension beyond the edge of the cone paper, the cone paper can be enlarged to approximate the diameter of the cylindrical housing, and the air inside the cylindrical housing can be more forcibly powered.

[0022] The invention according to claim 4 is the speaker according to any one of claims 1 to 3, wherein an enlarged portion having an enlarged diameter is provided at one end of the cylindrical housing. Is adopted as a diameter substantially equal to the diameter of the enlarged portion and attached to the enlarged portion.

[0023] By enlarging the diameter of one end of the housing to which the speaker unit is attached, and mounting the speaker unit corresponding to this diameter, a large-diameter speaker unit that cannot be mounted on the housing as it is with respect to the diameter. The air in the cylindrical housing can be more forcibly powered, as in the third aspect of the invention.

Of course, a synergistic effect can be obtained by using a speaker unit attached to the enlarged portion as a speaker unit provided with an extended portion on the cone paper according to the third aspect of the present invention. The invention's effect

[0025] According to the invention of claim 1, since a full-range speaker having good sound quality can be obtained by using a cylindrical housing which is conventionally regarded as having poor sound quality as the full-range speaker, the speaker can be obtained. There is no restriction on the pipe type in the case, and the degree of freedom in design increases.

[0026] In addition, the cylindrical housing and the cone paper of the speaker unit are similar to the relationship between the cylinder and the piston, and the cylindrical housing has substantially the same cross-sectional area as the cylinder (housing) and the piston (cone). Because the air is forced into the interior without any escape space (piston effect), the length of the tube is free to be affected by the resonance frequency (resonance) determined by the length of the tube. , And even with a small speaker unit, bass sound of sufficient volume, similar to a large-diameter speaker, can be obtained.

[0027] Furthermore, since the casing can be obtained simply by cutting a pipe-shaped material that is relatively easy to obtain, it can be manufactured at a lower cost and easier than an ordinary speaker enclosure. It comes out.

[0028] According to the second aspect of the present invention, an omnidirectional speaker in a tower-type housing can be obtained, so that the speaker has a small installation floor area and a distinctive design, even if the space is small. It can be installed so that it does not visually affect the surrounding environment, or on the contrary, it is decorated and decorated so that it stands out, such as a coffee shop, live band store, museum, museum, open space It can be used in various places where omnidirectional speed is required regardless of the listening position, such as a general home.

According to the third aspect of the invention, by increasing the area of the cone, which is the driving portion of the speaker unit, the air inside the cylindrical housing can be moved more efficiently, and a rich sound volume can be obtained. You will be able to obtain.

[0030] According to the invention of claim 4, the speaker unit is attached to the enlarged portion having a diameter larger than the diameter of the cylindrical housing, so that the area of the cone paper of the speaker unit with respect to the diameter of the housing. The pressure can be increased, and the pressure inside the cylindrical housing can be more effectively applied.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 is a front sectional view showing an example of the speaker of the present invention.

[0032] The housing 1 constituting the speaker has a cylindrical shape with an internal cavity, and its height is about 90 cm.

Approximately 89 mm in diameter, it should be large enough to be installed in ordinary living rooms as well as in ordinary halls and coffee shops.

[0033] The material of the housing 1 is not particularly limited, but it is made of a lightweight and strong material such as a wood resin molding or a metal (aluminum or the like). It is also low in cost.

[0034] At the upper end of the housing 1, a speaker unit 2 having a diameter of about 8 cm is installed facing upward and sealed. This speaker unit 2 is obtained by shaving the outer peripheral frame of a commercially available speaker unit and, if possible, removing the speaker unit. The dimensional difference between the outer diameter of 2 and the outer diameter of the cone paper should be eliminated.

[0035] A disk 5 having a diameter substantially equal to the diameter of the housing 1 is provided at the upper end of a column 5 extending vertically upward from several places (for example, four points) around the speaker unit 2 at the upper end of the housing 1. Shaped top plate 6 At the center of the top plate 6, a downwardly substantially conical cone 7 facing the speaker unit 2 is fixed.

[0036] The cone 7 plays a role as a sound diffuser, and is made of a hard material capable of reflecting sound, and has a size substantially equal to the diameter of the speaker unit 2 and is good. Is approximately 45 °, and the sound emitted upward from the speaker unit 2 is changed in the lateral direction by the slope of the cone 7 and is substantially conical, so the sound is equally distributed in all directions around it. The reflected sound is diffused from the space between the top plate 6 and the speaker unit 2 over a 360 ° circumference in the horizontal direction.

[0037] A sound absorbing material 8 made of thick (about 7 mm) glass wool or quilt sheets is adhered to the entire inner wall inside the housing 1 to completely prevent standing waves in the housing 1 Like! /

[0038] Further, as shown by the dashed line in the figure, if the sound absorbing material ^ was suspended around the magnet of the speaker unit 2, the standing wave could be more effectively absorbed.

[0039] At the lower end of the housing 1, a notch is provided in the housing 1 to which the force to which the bottom plate 9 is connected. An opening 10 is formed at the lowermost end of the body 1.

[0040] If the bottom plate 9 is large enough to maintain the upright state of the cylindrical housing 1,

However, its outer shape and material are not particularly limited.

The loudspeaker 1 of this embodiment has the above-described configuration, and the middle tone and the treble sound become a spherical wave 3 shown in FIG. 5B from the front of the speaker unit 2, and furthermore, a substantially conical cone 7. The sound is diffused in all directions, and the bass sound is the sound behind the speaker unit 2 as shown in Fig. 5 (B).

It can be used as 4 and can drive bass efficiently using the principle of a syringe.

In the embodiment of the present invention, the height (length) of the housing 1 is set to 90 cm, the force is not only 90 cm (around lm), but also 1.5 m, 3 m, etc. Any length can be used depending on considerations.

A significant difference between the speaker of the present invention and a musical instrument utilizing resonance of an acoustic tube is that, in the case of a pipe organ or a flute, because of free vibration, a force at which resonance occurs at a resonance frequency determined by the length of the tube. In the case of, it is not resonance because of the controlled sound drive. [0044] In the equation of the resonance frequency f, f = nc / 2L (Hz) (n: positive integer, c: speed of sound, L: length of the pipe) Assuming that the sound speed is about 340mZs and the length of the cylinder is lm , F ^ l70Hz, but half of 85Hz, 42.5Hz of 1Z4 could be reproduced enough.

On the other hand, in the case of the conventional back load horn type, the frequency characteristics depended on the shape of the cylinder, and a horn length of 3 m was required to obtain a similar low tone.

In this embodiment, an example is shown in which a speaker unit 2 having a diameter of 8 cm is attached. The diameter of the speaker unit 2 is the same regardless of the diameter of the 8 cm, 10 cm, 12 cm, 16 cm, and 20 cm speakers. There is bass.

That is, it does not relate to the limit value (lowest resonance frequency: fO) of the low-frequency reproduction frequency of the speaker unit 2. In particular, the fO of the speaker unit 2 with a diameter of 8 cm was 140 Hz, and although it could not output 40 Hz, it could be reproduced sufficiently and the bass drum sound could be produced clearly.

[0048] Further, the level of the bass changes depending on the width of the gap in the vertical direction of the opening 10 which serves as a passage for bass. In the case of this embodiment, the force in which the vertical width of the gap in the opening is about 10 mm is obtained. As shown in the figure, compared to the frequency characteristic A with a gap of 10 mm, the frequency characteristic B with a small gap of 5 mm has a lower sound pressure level in the low-frequency range, and the gap with a large gap of 30 mm. In the case of the frequency characteristic C, the sound pressure level in the low range was increased, and the tone of the low range became lighter.

FIG. 3A is a front sectional view showing a speaker unit 2 suitable for the speaker of the present invention. Compared with a conventional speaker unit, the area of the vibrating paper (cone paper 11) is smaller than the diameter of the speaker unit 2. FIG. 3 (B) shows a comparison of the conventional speaker unit 2 when the area of the cone paper 11 is the same.

[0050] Both the speaker unit 2 of the present invention and the conventional one generate a sound by vibrating the cone paper 11 by the action of the magnet 12 and the coil 13, and the conventional one has the periphery of the cone paper 11, Between the frame 14 (for connection to the housing 1) and a flexible edge portion 15 for connecting to the cabinet 14 without disturbing the vibration of the cone paper 11, a ring is provided. Note that a damper 16 is provided below the cone paper 11 to prevent vibration due to inertia of the cone paper 11.

[0051] Due to the presence of the edge portion 15, the diameter of the cone paper 11 is reduced to the whole of the speaker unit 2. Although it is smaller than the diameter, in the speaker unit of the present invention, the area of the cone paper 11 can be increased as much as possible with respect to the speaker unit 2 by providing the cone paper 11 with an extension 1 mm beyond the edge 15. did it.

[0052] When the area of the cone paper 11 is larger than the size of the speaker unit 2, the piston effect for moving the sound for the housing 1 is further increased.

[0053] For example, even with a speaker unit having a diameter of 8cm, the frame paper has a diameter of about 77mm, the outer edge part has a diameter of about 68mm, and the outermost edge of the cone paper has a diameter of about 54mm. 11 is provided with an extension 1 mm so that it overlaps with the edge, so that the diameter of cone paper 11 is about 68 mm, and if it is further extended to the frame, the diameter of cone paper 11 can be about 77 mm. Will be.

For example, the area S of the conventional cone paper is S = 2289 mm ² as 54 φ, and the area S of the cone paper provided with the extension part near the edge is S = 3629 mm ² as 68 φ,

twenty two

Furthermore, the area S of the cone paper provided with an extension to the frame part is S = 4654 m as 77 φ

3 3 m ² .

[0055] As described above, merely providing the extension 1 コーン in the cone paper 11 increases the area of the cone paper to about twice, and further enhances the piston effect for driving air to the cylindrical housing 1. You can expect it.

FIG. 4 shows another embodiment of the speaker of the present invention, in which an enlarged portion 17 having a diameter near the upper end portion of the housing 1 larger than other portions is provided. A speaker unit 2 having a diameter substantially equal to the diameter of the speaker unit 2 is attached to the enlarged portion 17.

In this case, the area of the cone paper of the speaker unit 2 for driving the air is increased with respect to the diameter of the housing 1, and the effect of the piston for driving the air can be more expected.

[0058] The enlargement ratio for the other portion of the enlargement portion 17 in the housing 1 is not particularly limited. However, if the enlargement ratio is too large, the amount of air to power the speaker unit is reduced. Since it is too small, the diameter ratio of the enlarged portion 17 to the other portion of the housing 1 may be appropriately determined within a range of 1.2: 1 to 2: 1.

Brief Description of Drawings FIG. 1 is a front sectional view showing a speaker of the present invention.

FIG. 2 is a graph showing frequency characteristics of the speaker of the present invention.

FIG. 3 (A) is a front sectional view of a speaker unit used for the speaker of the present invention, and FIG. 3 (B) is a front sectional view of a conventional speaker unit described for comparison.

FIG. 4 is a front sectional view showing another embodiment of the speaker of the present invention.

FIG. 5 (A) is an explanatory diagram showing sound propagation of a conventional speaker, and FIG. 5 (B) is an explanatory diagram showing sound propagation of the present invention.

Explanation of symbols

[0060] 1 housing

2 Speaker unit

3 spherical wave

4 Plane wave

5 props

6 Top plate

7 cones

8, 8 'sound absorbing material

9 Bottom plate

10 opening

11 cone paper

1 延長 Extension

12 Magnet

13 Koinole

14 frames

15 Edge

16 Damper

17 Enlarged section

Claims

The scope of the claims

[1] A speaker housing having a diameter substantially equal to the cylindrical diameter of the housing is externally attached to one end of the cylindrical housing and sealed, and a sound absorbing material is provided on the inner surface of the housing. Speaker.

[2] The case is raised with the speaker side up, and a bottom plate is provided at the lower end of the case so as to provide a gap between the case and the reflector, and a substantially conical reflector is provided at the upper end. 2. The loudspeaker according to claim 1, wherein the conical tip is provided so as to face the loudspeaker to form an omnidirectional loudspeaker.

[3] The speaker according to claim 1 or 2, wherein the speaker unit uses a speaker in which an effective diameter of the cone paper is made larger by providing an extension portion beyond the edge portion on the cone paper.

[4] An enlarged portion having an enlarged diameter is provided at one end of the cylindrical housing, and the speaker unit is attached to the enlarged portion with a diameter substantially equal to the diameter of the enlarged portion. No !, the speaker described in the section.