JPH0759118B2 - Speaker Enclosure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention The present invention relates to a loudspeaker enclosure having means for buffering sound pressure.

2. Description of the Related Art For speaker enclosures that ideally have infinite baffle, sound pressure processing behind the baffle plate is an essential problem. Thus, various methods devised for the sound pressure processing have been provided. The typical method is
There are a closed system shown in FIG. 27, a bass reflex system shown in FIG. 28, a drone cone system shown in FIG. 29, and a back road horn system shown in FIG. The bass reflex system, the drone cone system, and the back road horn system are intended to effectively utilize the sound pressure appearing on the back surface of the speaker (1a), and an opening for outputting a phase-reversed bass to a part of the enclosure (2). Since (3) or the drone cone (4) is present, it is efficient in the low frequency range and produces a so-called good sound, but the air spring for braking the speaker vibration system becomes weak, and the vibration system Since it has an opening diameter and / or a duct length and / or a resonance frequency that can be formed by a drone cone, the sound tends to be solid or discolored. The other typical method, the closed method,
To prevent the sound coming out of the rear of the speaker (1a) from coming out, an acoustic suspension method that uses a large amount of sound absorbing material, and an air spring trapped in the enclosure (2) are used. There is an air suspension system that supports the vibration system of the speaker (1) having a low minimum resonance frequency (f ₀ ). Although these closed types do not produce a solid low tone, resistance that blocks the vibration of the cone paper (1b) is generated, and a pinch sound, the air spring resonates too much, and the enclosure is closed. There was a tendency for the sound to be distorted by the standing wave in the ear (2).

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The present invention is such that standing waves are difficult to reach in the enclosure,
The constant of the air spring that brakes the speaker vibration system can be set freely, and accordingly, there is no tight sound, and a discolored sound like the bass reflex system, the drone cone system, and the back road horn system. It is to provide a speaker enclosure that can produce an ideal sound without producing a squeaky sound in a closed system, a sound due to resonance of an air spring, and a distorted sound. It is intended.

[Structure of Invention]

Means for Solving the Problems In order to achieve the above-mentioned object, the present invention has a structure of a speaker enclosure in which a bellows-like sound pressure buffering means is provided in an enclosure having a baffle plate to which a speaker unit is attached. Is.

That is, the present invention provides a bellows-like sound pressure buffering means, which is formed of an elastic material such as synthetic resin, with appropriate internal loss, spring constant and responsiveness, at any part of the speaker enclosure. By receiving the sound pressure from the rear of the speaker by the bellows-like sound pressure buffering means, the spring constant corresponding to the air spring from infinity is also given to the bellows-like sound pressure buffering means, so that the sound pressure buffering degree is infinite. If the bounced sound is somewhat the same as that of baffle, and if a bounced sound like a closed type enclosure is required, the sound quality is adjusted by using bellows-like sound pressure buffering means with a large expansion and contraction elasticity of the bellows. In addition, the structure is such that the sound pressure from the speaker is concentrated on the bellows-shaped cushioning means partially provided in the enclosure, or the enclosure is Is obtained to be able to attenuate standing waves by the majority structure occupied by the bellows-like cushioning means.

Embodiment 1 Embodiment 1 ... The embodiment shown in FIG. 1 to FIG. 3, wherein an enclosure (made of hard synthetic resin or other hard material is provided behind a baffle plate (2a) to which a speaker unit (1) is attached ( By forming 2b ') (2b ") (2b) (2b') (2b"), an enclosure (2) is formed by the baffle plate (2a) and the enclosure, and the enclosure (2) is formed. An open edge (5b) of a bellows (5) whose upper surface is a bellows-like sound pressure buffering means is closed and the lower side is opened is attached to the upper surface (2b ') of 2), and the bellows (5) is attached.
On the upper surface (2b ') of the enclosure (2) inside
A communication hole (6) communicating with the inside of the bellows (5) is formed. (5a) is the upper closed part of the bellows,
(1a) is the speaker body, (1b) is the cone paper forming the speaker unit (1), (1c) is the center cap, (1a) is the connection, and (1e) and (1f) are the + and-terminals. The bellows (5) is made of, for example, a synthetic resin or the like having a proper internal loss of sound pressure generated in the rear of the speaker body (1a) and a spring constant and responsiveness suitable for the sound pressure of the speaker. It is made of elastic material.

In the above-mentioned embodiment, the sound pressure generated behind the speaker body (1a) enters the bellows (5) through the communication hole (6) and expands and contracts the bellows (5) to generate a low frequency sound of 30Hz to 200Hz. The sound pressure is buffered and absorbed by the piston movement due to the expansion and contraction of the bellows (5), and the sound pressure of the mid-range sound of 200 Hz to 3 KHz is buffered and absorbed by the diffuse reflection and minute vibration due to the folds of the bellows (5). Thus, depending on the length of the bellows (5), the strength of the spring, and the degree of sound pressure loss, the load of the speaker can be varied from the almost infinite baffle characteristic to the closed type characteristic. In addition, in order to reduce the appropriate sound pressure, a small hole (not shown) is provided in the closed portion (5a) of the bellows (5) or the material of the bellows (5) is slightly breathable. It is possible to use a certain material. As the material of the bellows (5), for example, paper, a soft synthetic resin sheet, a hard synthetic resin sheet, a metal sheet, a single material suitable for the bellows or a composite material thereof is used.

Further, in FIG. 3, the bellows (5) and the enclosure (2) are attached to each other by connecting the open edge (5b) of the bellows (5) to the upper surface (2b ') of the enclosure (2). Although the embodiment in which the periphery of (6) is fixed by adhesion is shown, the bellows (5) can be attached to and detached from the enclosure (2) as described in the embodiments shown in FIGS. 4 to 7 described later. May be attached. (5c) is an open part.

Second embodiment ... The embodiment shown in FIGS. 8 and 9
Baffle plate (2a) with speaker unit (1) attached
Behind the enclosure of hard synthetic resin and other hard materials (2
b ') (2b ") (2b) (2b') (2b") is formed to form an enclosure (2) by the baffle plate (2a) and the enclosure, and the enclosure (2) is formed. 2) Bellows (5) similar to the first embodiment on both left and right sides
It shows an embodiment in which (5) is attached respectively. The eighth
In Fig. 9 and Fig. 9, the same reference numerals as those in Fig. 1 to Fig. 3 indicate the same parts, and means for obtaining an appropriate internal loss of sound pressure in the rear of the speaker body (1a), The bellows (5) and (5) are made of a material having a spring constant and responsiveness suitable for the sound pressure of the speaker, which is the same as in the first embodiment, and buffers the sound pressure of the low range sound and the middle range sound. The absorbing action is similar to that of the first embodiment. The attachment of the bellows (5) (5) and the enclosure (2) is similar to that of the embodiment shown in FIG. 3 or the embodiment shown in FIGS. 4 to 7 described later.

Third Embodiment ... The embodiment shown in FIGS. 10 to 13 and showing a portable speaker enclosure.
In the above embodiment, the enclosure (2) having an open rear surface is provided behind the baffle plate (2a) to which the speaker unit (1) is attached.
b ′) (2b) (2b ′) (2b ″) is formed, and the rear opening portion (7) of the enclosure is formed by a lid body (8) on one edge of the enclosure, one edge of which is hinged. , And an enclosing member (2) that can be opened and closed.
Speaker unit (1) protruding to the back side on the back side of the
Bellows (5) similar to those of the first embodiment as they are coated
The open edge (5b) of the is solidly or removably attached by gluing or other means. When the speaker (1a) is used, the lid (8) is opened as shown in FIG. 12, and when carrying it, the lid is fixed as shown in FIG. (9) is a hinge,
(10) is a closed state holding member. Incidentally, in FIGS. 10 to 13, the same reference numerals as those in FIGS. 1 to 3 indicate the same parts as those in FIGS. 1 to 3, and an appropriate internal loss of sound pressure in the rear of the speaker (1a). The bellows (5) may be configured by using a material for obtaining the sound pressure, a spring constant suitable for the sound pressure of the speaker, and a responsive material, as in the first embodiment. The sound pressure buffering and absorbing action of is similar to that of the first embodiment. The bellows (5) and the enclosure (2) can be attached by fixing with an adhesive or detachable with screws or the like.

Fourth embodiment: This is an embodiment shown in FIGS. 14 to 16.
In this embodiment, the interior of the enclosure (2) shown in FIG. 3 is provided with a vertical partition plate (11) behind the speaker unit (1) so that the interior of the enclosure (2) is improved. Is divided into front and rear two chambers (A) and (B), a communication hole (6) communicating with the open part (5c) of the bellows (5) is provided in the partition plate (11), and the enclosure (2) A through hole (12) communicating with the rear chamber (B) is formed on the rear surface (2b ″), and an open edge (5b) of the bellows (5) is formed around the communication hole (6) in the rear chamber (B). In addition, in FIGS. 14 to 16, the same reference numerals as those in FIGS. 1 to 3 indicate the same parts as those in FIGS. 1 to 3, and the sound pressure appropriate to the rear of the speaker body (1a) is appropriate. To obtain the internal loss of the bellows (5) using a spring constant and a responsive material suitable for the sound pressure of the speaker. Is also the same as that of the first embodiment, and the sound pressure buffering / absorbing action of low-range sounds and middle-range sounds is also the same as that of the first embodiment. Incidentally, the bellows (5) and the enclosure (2) The mounting is made by fixing with an adhesive, but is made removable as in the mounting example shown in Fig. 4 to Fig. 7. In the fourth embodiment, the rear chamber (B) with the bellows (5) mounted. Since the through hole (12) is formed in the rear surface (2b ″) of the enclosure (2) of (1), the expansion and contraction of the bellows (5) by sound pressure becomes sharp.

Fifth embodiment: the embodiment shown in FIG. 17, in which the enclosure (2b ') (2b ") (2b"(2b') is provided behind the baffle plate (2a) to which the speaker unit (1) is attached. By forming (2b ″), the baffle plate (2a) and the enclosure form an enclosure (2), which is inside the enclosure (2) and above the speaker unit (1). A lateral partition plate (13) is provided in the upper and lower chambers (C) (D) inside the enclosure (2) by the partition plate (13).
And the open portion (14) is formed in the circumferential direction of any one of the upper chambers (A). The partition plate (13) is formed with a communication hole (6) having a relatively large diameter that communicates the upper chamber (A) and the lower chamber (B), and the communication hole (6) of the communication chamber (6) is formed in the upper chamber (A). Install the open edge (5b) of the bellows (5) around it. Note that in FIG. 17, the same reference numerals as those in FIGS. 1 to 3 indicate the same parts as those in FIGS. 1 to 3 in order to obtain a proper internal loss of sound pressure in the rear of the speaker body (1a). Also, the bellows (5) may be configured by using the above-mentioned means, a spring constant suitable for the sound pressure of the speaker, and a responsive material, as in the first embodiment. The buffer absorption function is similar to that of the first embodiment. The bellows (5) and the enclosure (2) are attached by bonding the open edge (5a) of the bellows (5) around the communication hole (6) of the partition plate (13) as shown in FIG. In addition to the means, it may be detachable as in the mounting example shown in FIGS. 4 to 7 described later. In the fifth embodiment, since the open portion (14) is formed in the circumferential direction of either one of the upper chambers (A) provided with the bellows (5), the expansion and contraction of the bellows (5) due to sound pressure is sensitive. Becomes

Sixth embodiment ... The embodiment shown in FIG. 18, in which the enclosure (2b ') is provided behind the baffle plate (2a) to which the speaker unit (1) is attached by a hard synthetic resin or other hard material.
By forming (2b ″) (2b) (2b ′) (2b ″), the baffle plate (2a) and the enclosure form an enclosure (2), and inside the enclosure (2) A reflector (15) is provided diagonally on the upper rear part. The bottom surface (2b) of the enclosure (2) has a relatively large diameter communication hole (6) communicating with the inside of the bellows (5) described below, and the bellows mounting ring with a flange is formed in the communication hole (6). (16)
Are fitted, the open edge (5b) of the bellows (15) is fitted externally or internally to the mounting ring (16), and is detachably fixed by a screw (17). Closed part (5a) of bellows (5)
A small hole (18) is provided to reduce the load on the speaker unit (1), or the bellows itself is made of a breathable material. Closed part (5a) of bellows (5)
Project toward the peripheral edge, and the diameter or cross-sectional shape of the bellows (5) is gradually changed. (19) is a light source provided inside the enclosure, and a fluorescent paint may be used. A transparent window (22) with an output level scale is provided on both or either of the legs (20) and (21) provided on the bottom surface (2b) of the enclosure (2), and the closing portion (5a) is projected. The sound pressure can be directly observed by looking at the edge (5a ') of the portion through the transparent window (22).

Seventh embodiment ... In the embodiment shown in FIG. 19, the bottom plate (2b) bent backward is formed at the bottom of the baffle plate (2a) to which the speaker unit (1) is attached, and the baffle plate (2
The back edge of a) surrounds the outside of the speaker unit (1), and the open edge (5b) of the bellows (5), which is formed in a frusto-conical shape so that the diameter becomes gradually smaller, is glued or screwed. After fixing by means such as a stop, the baffle plate (2a) and the bellows (5) form an enclosure (2).

Eighth embodiment ... In the embodiment shown in FIG. 20, the enclosure (2b ') (2) is made of hard synthetic resin or other hard material behind the baffle plate (2a) to which the speaker unit (1) is attached.
b ") (2b) (2b ') (2b") to form an enclosure (2) by the baffle plate (2a) and the enclosure, and the rear surface of the enclosure is closed. How to open the bellows (5) by recessing it so that the closing part (5a) of the bellows (5) whose diameter gradually decreases toward the part (5a) is located inside the enclosure (2). It has a rim (5b) attached.

Ninth embodiment ... The embodiment shown in FIG. 21, which is the eighth embodiment shown in FIG. 20. The bellows (5) is continuous with the closing portion (5a) of the bellows (5). It shows an embodiment in which a small bellows (5c) protruding inward is formed.

Tenth embodiment: the embodiment shown in FIG. 22 in which the bellows (5) of the fourth embodiment shown in FIG. 16 becomes smaller in diameter as it reaches the closing portion (5a), and becomes a truncated cone shape. The through hole (12) formed in the rear surface (2b ″) of the enclosure (2) and communicating with the rear chamber (B) is a small hole. (11) is a partition plate.

Eleventh embodiment: the embodiment shown in FIG. 23, in which the horn-shaped enclosure (23) is connected behind the baffle plate (2a) to which the speaker unit (1) is attached, and the baffle plate (5). And a horn-shaped enclosure (23) form an enclosure (2), and the lower part of the enclosure (2) is formed by a box (25) having a small hole (24) in the bottom surface (25a). A bellows (5) having a closing portion (5a) on the lower surface is formed continuously in the lower part of the enclosure (2) in the box (25) so as to surround the closing portion (5a) of the bellows (5).
The inner bottom surface (25a ') of the box (25) by the spring (26)
It shows an embodiment in which a ball is stopped around the small hole (24).

Twelfth embodiment: the embodiment shown in Fig. 24, in which the enclosure (2b ') (2b ") (2b"(2b') is provided behind the baffle plate (2a) to which the speaker unit (1) is attached. (2b ″) is continuously formed with a baffle plate (2a) and the enclosure to form an enclosure (2), and a recessed portion (2) which is recessed downwardly on the upper surface (2b ′) of the enclosure (2). 27) is provided, and a communication hole (6) communicating with the inside of the enclosure (2) is provided in the recessed bottom (27a), and is provided on the recessed bottom (27a) and around the communication hole (6). , A truncated conical bellows (5) whose diameter gradually decreases toward the upper side, and a model or mobile (28) is fixed on the closed part (5a) formed on the upper part of the bellows (5) However, as the bellows (5) expands and contracts, the model or mobile (28) vibrates up and down to make the eyes entertaining.

Thirteenth embodiment: In the embodiment shown in FIG. 25, a sound absorbing material (29) is struck in a bellows (5) attached to an enclosure (2) or a partition plate (11) or (13). (30) is a spring receiving frame, and (31) is a spring.

The sixth embodiment shown in FIG. 18, the seventh embodiment shown in FIG. 19, the eighth embodiment shown in FIG. 20, the ninth embodiment shown in FIG. 21, the tenth embodiment shown in FIG. 22, and the tenth embodiment shown in FIG. In the eleventh embodiment, the twelfth embodiment shown in FIG. 24, and the thirteenth embodiment shown in FIG. 25, the same symbols as those in FIGS.
The same parts as in FIGS. 3 to 3 are shown and the speaker body (1a)
Means for obtaining a moderate internal loss of sound pressure emitted at the rear of the
Similar to the first embodiment, the bellows (5) is made of a material having a spring constant and responsiveness suitable for the sound pressure of the speaker, which is also the same as in the first embodiment, and also has a sound pressure buffering effect for low-range sounds and middle-range sounds. First
It is similar to the embodiment.

Except for the 11th embodiment shown in FIG. 23, the open portion (5c) of the bellows (5) and the enclosure (2) of the other embodiment,
Alternatively, the attachment means between the open portion (5c) of the bellows (5) and the partition plate (11) or (13) may be fixed by adhesion or may be detachable attachment means shown in FIGS. 4 to 7, for example. That is, in FIG. 4, the open edge (5b) of the bellows (5) is bent outward in a substantially U-shape, and the U-shaped portion (5d) is enclosed (2).
Alternatively, it is detachably fitted to the edge of the communication hole (6) provided in the partition plate (11) or (13). FIG. 5 shows that the open edge (5b) of the bellows (5) shown in FIG. 4 is extended inward to form an inwardly extending portion (5b '). FIG. 6 shows that the open edge (5b) of the bellows (5) is applied to the peripheral edge of the communication hole (6) provided in the enclosure (2) or the partition plate (11) or (13), and the ring-shaped metal (32) The screw (33) is screwed into the enclosure (2) or the partition plate (11) or (13) via the () to fix it under pressure. FIG. 7 is an enclosure (2) around the periphery of the communication hole (6) in the state of FIG.
Alternatively, a ring-shaped metal plate (32) is applied from the back side of the partition plate (11) or (13), and a screw (33) is screwed onto the enclosure (2) or the partition plate (11) or (13) and fixed by pressure. is there.

Action: The action of the present invention will be described below with reference to the equivalent circuit shown in FIG. The sound pressure from the rear of the speaker unit (1) is the volume of the enclosure (2) (C _MC1 ).
It is buffered by the air spring (M ₁ ) at, but when it is added in series, the minimum resonance frequency (f ₀ ) will rise. The raised minimum resonance frequency (f ₀ ) is further buffered by the air spring (M ₂ ) in the volume (C _MC2 ) in the bellows (5). Thus, the sound pressure of the low-range sound is buffered and absorbed by the expansion and contraction movement of the bellows (5), that is, the piston movement, and the sound pressure of the middle-range sound is buffered and absorbed by the irregular reflection and minute movement by the folds of the bellows (5).

Thus, by giving the bellows-shaped sound pressure buffering means a spring constant corresponding to the spring of air from infinity, the sound pressure buffering level is made to be about the same as infinity baffle, and if it is a little like a closed type enclosure. When sound is required, the sound quality is adjusted by using bellows-like sound pressure buffering means having a relatively large expansion and contraction elasticity of the bellows (5), and the sound pressure from the speaker is partially applied to the enclosure (2). The sound pressure is adjusted by using the bellows-like sound pressure absorbing means provided in the speaker unit so that the sound pressure of the speaker unit (1) is concentrated on the bellows-like sound absorbing means partially provided in the enclosure (2). The standing wave is attenuated by adopting a different structure or a structure in which the bellows-like buffer means occupies most of the enclosure. 31st
Figure is a graph showing the impedance characteristics and sound pressure frequency characteristics of the present invention, a graph showing a state in which the sound pressure characteristics 500Hz or lower bass sound pressure is increased near 2.5 decibels,
FIG. 32 is a graph showing the acoustic characteristics of a known closed speaker enclosure when the sound pressure in the low frequency range of 500 Hz or less is not increased.

〔The invention's effect〕

The present invention makes it difficult for standing waves to reach within the enclosure.
The constant of the air spring that brakes the speaker vibration system can be set freely, and accordingly, there is no tight sound, and a discolored sound like the bass reflex system, the drone cone system, and the back road horn system. It is possible to provide a loudspeaker enclosure that can produce an ideal sound without producing a squealing sound in a sealed system, a sound due to resonance of an air spring, and a distorted sound. There is an effect that can be done.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 to FIG. 26 in the drawings show an embodiment of the present invention. FIG. 1 is a plan view of the first embodiment of the present invention, and FIG. Figures and 3 are vertical cross-sectional views of Figure 1-XX '.
4 to 7 are longitudinal sectional views showing a state where the bellows and the enclosure or the partition plate of the present invention are attached, FIG. 8 is a perspective view of the second embodiment of the present invention, and FIG. FIG. 10 is a plan view of the third embodiment, FIG. 11 is a front view of the same, and FIG. 12 is a tenth view of the third embodiment when the lid is open.
FIG. 13 is a vertical sectional view of FIG. ZZ ′, FIG. 13 is a vertical sectional view of FIG. 10 ZZ ′ in the closed state of the third embodiment, and FIG. 14 is a plan view of the fourth embodiment. Is the front view, FIG. 16 is the FIG. 14 P-
Fig. 17 is a vertical sectional view of P ', and Fig. 17 is a vertical sectional view of the fifth embodiment.
FIG. 16 is a vertical sectional view of the sixth embodiment, FIG. 19 is a vertical sectional view of the seventh embodiment, FIG. 20 is a vertical sectional view of the eighth embodiment, and FIG. 21 is a vertical sectional view of the ninth embodiment. FIG. 22 is a vertical sectional view of the tenth embodiment,
23 is a vertical sectional view of the 11th embodiment, FIG. 24 is a vertical sectional view of the 12th embodiment, FIG. 25 is a vertical sectional view of the 13th embodiment, FIG. 26 is an equivalent circuit diagram of the present invention, FIG. 27 is a vertical sectional view of a known closed-type speaker enclosure, FIG. 28 is a vertical sectional view of a known bass reflex system speaker enclosure, and FIG. 29 is a known drone-cone speaker enclosure. Fig. 30 is a vertical sectional view of a jar, Fig. 30 is a vertical sectional view of a known backroad horn system, Fig. 31 is a graph showing an impedance characteristic curve of the present invention, and Fig. 32 is a known sealed system speaker enclosure. It is a graph which shows an impedance curve. (1) …… Speaker unit, (2) Enclosure, (2a) …… Baffle board, (5) …… Bellows.

Claims (1)

[Claims] 1. A speaker enclosure having a bellows-like sound pressure buffering means in an enclosure having a baffle plate to which a speaker unit is attached.