JP2000032578A - Small-sized loudspeaker system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To extend low frequency characteristics and to improve the sound quality in the entire range or the like by enhancing the low frequency characteristics and the transition characteristics of the loudspeaker system, while the loudspeaker system is made small and made light and a gap that is adjustable easily and properly is formed between an outer circumferential rear face of a loudspeaker unit and a baffle plate front face along nearly the entire inner circumferential of an opening of a baffle board. SOLUTION: In this loudspeaker system, an outer circumferential flange 13a of a woofer loudspeaker unit 13 is fitted to a baffle board 11, so that a prescribed gap is formed that acts as a vent path communicating the inside and the outside of an enclosure 10 between a front face of the baffle board 11 and a torus rim 16 attached to a rear face. That is, plural tubular spacers 17 are interposed between the front face of the baffle board 11 and the inner face of the torus rim 16 placed at a rear face of the outer circumferential flange 13A of the woofer loudspeaker unit 13 for attaching the woofer loudspeaker unit 13 to the baffle board 11 with machine screws 18 as mount jigs inserted to the spacers 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to all loudspeaker systems using loudspeakers such as an SR system, a home audio loudspeaker system, and a suitable loudspeaker system such as an on-vehicle audio loudspeaker system, and more particularly to improving sound quality. About technology.

[0002]

2. Description of the Related Art In a conventional loudspeaker system, generally, importance is placed on the hermeticity of an enclosure. this is,
This is because sound pressure leakage from the enclosure adversely affects the frequency characteristics. That is, the sound wave leaking from the enclosure interferes with the direct sound from the speaker system and disturbs the frequency characteristics. In particular, as the sound wave leaks from a portion farther from the speaker unit, the phase of the sound pressure in the enclosure is more likely to be uniform and sharper. Causes interference.

[0003] Therefore, it is an iron rule that a typical speaker unit is mounted on a baffle of an enclosure by keeping airtightness of its mounting surface, and this mounting method is treated in a textbook. For example, as shown in FIG. 12, the speaker unit 1 is attached with the inner surface of the flange 2 at the outer periphery thereof and the front surface of the baffle plate 4 of the enclosure 3 in close contact with each other.
The outer surface of the flange portion 2 and the rear surface of the baffle plate 4 are attached in close contact with each other.

[0004]

Generally, the low-frequency characteristics of a speaker system are limited to the lowest resonance frequency of the unit, and if the enclosure in which it is installed has sufficient capacity, the lowest resonance frequency of the unit is reduced. Although it is a condition for reproduction, in the conventional speaker system that emphasizes the tightness of the enclosure, the low frequency characteristics and transient of the speaker system are affected by the influence of the inertial vibration of the air spring inside the enclosure on the diaphragm. The characteristics are adversely affected, and particularly when the mounting capacity is smaller than the enclosure capacity required by the speaker unit, the attenuation of the low-frequency characteristics becomes remarkable.
In order to solve this problem, the present applicant has previously filed Japanese Patent Application No. 9-335004, which is formed around the entire inner circumference of the opening of the baffle plate at the outer periphery of the speaker unit, and A speaker system characterized by providing a predetermined ventilation path communicating with the speaker system.

However, it has been found that the effect of the proposed technique largely depends on the shape and area of the mounting rib of the speaker unit. In particular, in a small-sized speaker system in which the enclosure is reduced in size, the outer peripheral portion of the speaker unit is used. Adjust the gap formed along the entire inner circumference of the baffle plate between the rear surface and the front surface of the baffle plate, and if the length of the ventilation path is not properly adjusted, the speaker unit vibration due to the air inside the enclosure The mass added to the plate is reduced, and the low-frequency reproduction characteristics are attenuated.

However, in the case of a low-pitched speaker unit in which a rib portion of a frame serving as a mounting surface to a baffle plate does not have a uniform ring shape, a small-diameter speaker unit having a small-diameter mounting surface area, The gap formed along the substantially entire inner circumference of the opening of the baffle plate between the rear surface of the outer periphery of the speaker unit and the front surface of the baffle plate cannot be adjusted. For example, extension of low-frequency characteristics and improvement of sound quality in the entire region And so on.

On the other hand, in a mid-range loudspeaker system or a high-range loudspeaker system, the sound inside the enclosure is emitted from the surroundings to improve the sense of localization of the sound image. Since the rib portion of the frame serving as the mounting surface is small, and the facing area between the rear surface of the outer peripheral portion of the speaker unit and the front surface of the baffle plate is small, the low-frequency characteristics are likely to deteriorate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. In a speaker system, the speaker system can be reduced in size and weight by a simple improvement of a mounting structure of a speaker unit enclosure to a baffle plate. While improving the low-frequency characteristics and transient characteristics of the speaker system, particularly along the substantially entire inner periphery of the opening of the baffle plate between the rear surface of the outer periphery of the speaker unit and the front surface of the baffle plate. An object of the present invention is to make it possible to easily and accurately adjust a gap portion to be formed, for example, to extend low-frequency characteristics and improve sound quality in the entire region.

[0009]

According to a first aspect of the present invention, there is provided a speaker system including an enclosure and a speaker unit attached to an opening of a baffle plate on a front surface of the enclosure. In the system, the speaker unit is formed along substantially the entire inner periphery of the opening of the baffle plate between the rear surface of the outer peripheral portion and the front surface of the baffle plate, and
The speaker unit is attached to the baffle plate so as to form a gap portion serving as a predetermined ventilation path communicating with the outside, and the rear surface of the outer peripheral portion of the speaker unit is adjusted to have an opposing area between the rear surface of the outer peripheral portion and the front surface of the baffle plate. A rim in the shape of an annular plate for providing the rim.

According to a second aspect of the present invention, there is provided a speaker unit having a plurality of annular rims located on a rear surface of the speaker unit and a plurality of rims projecting rearward from the rear surface of the annular rim. And a ring-shaped rib portion located at a position rearward from the rear surface of the annular plate-shaped rim portion and connecting the spacer portions to each other were integrally formed, and the rib portion was attached to the front surface of the baffle plate. It is characterized by the following.

According to a third aspect of the present invention, there is provided a speaker system including an enclosure and a speaker unit attached to an opening of a baffle plate on a front surface of the enclosure. Between the baffle plate and the rear surface of the baffle plate so that a gap is formed along substantially the entire inner periphery of the opening of the baffle plate and serves as a predetermined ventilation path communicating between inside and outside of the enclosure. An annular plate-shaped rim is provided on the front surface of the outer periphery of the speaker unit for adjusting the facing area between the front surface of the outer periphery and the rear surface of the baffle plate.

According to a fourth aspect of the present invention, there is provided a speaker unit having a plurality of annular rims located on the front surface of the speaker unit and a plurality of rims projecting forward from the front surface of the annular rim. And a ring-shaped rib portion located at a position forward of the front surface of the annular plate-shaped rim portion and interconnecting the spacer portions, were integrally formed, and the rib portion was attached to the rear surface of the baffle plate. It is characterized by the following.

The operation of the present invention will be described. According to the first and third aspects of the invention, the predetermined ventilation path communicating between the inside and the outside of the enclosure functions as a sound hole, and emits a resonance sound inside the enclosure by a bass reflex operation to enhance a bass range. Further, the influence of the inertial vibration of the air spring inside the enclosure on the diaphragm is reduced, the transient characteristics over the entire reproduction band are improved, and a sound quality that is stretchable and has no heaviness is obtained.

Further, since the ventilation path is formed in the outer peripheral portion of the speaker unit along substantially the entire inner periphery of the opening of the baffle plate, air uniformly flows in and out from the outer peripheral portion of the speaker unit. Because the unit cone paper curves smoothly toward the ventilation path,
The resistance received by the cone paper due to the air pressure change inside the enclosure is effectively reduced, and the sound quality can be more effectively improved.

Further, since the air passage is formed at a position close to the speaker unit, it is possible to enhance the bass frequency characteristics and to prevent disturbance of the characteristics at other frequencies. And with the bass speaker unit,
If the rib of the frame that is the mounting surface to the baffle plate does not have an even ring shape, or if the mounting surface area is small, the baffle plate is placed between the rear surface of the outer periphery of the speaker unit and the front surface of the baffle plate. In the case where the gap formed along substantially the entire inner circumference of the opening cannot be adjusted, a large-diameter circular plate-shaped rim is attached, and the rear or front of the outer peripheral portion of the speaker unit is attached to the rear or front surface of the speaker unit. By increasing the area facing the front surface or the rear surface of the baffle plate, extension of low-frequency characteristics and improvement of sound quality in the entire region can be easily achieved.

Also, in the middle-tone speaker system and the high-tone speaker system, when the sound inside the enclosure is emitted from the surroundings to improve the sense of localization of the sound image, a ring-shaped rim having a large diameter is used. By increasing the area facing the rear or front surface of the outer peripheral portion and the front or rear surface of the baffle plate on the rear or front surface of the outer peripheral portion of the speaker unit, deterioration of low-frequency characteristics can be prevented.

In particular, in the inventions according to the second and fourth aspects, the number of parts is reduced as an apparatus by integrating the ring-shaped rim and the spacer in advance in the speaker unit itself. Since the present invention can be applied to the speaker system by only attaching the loudspeaker, the manufacturing efficiency is excellent.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the attached drawings. First, the basic concept of the present invention will be described. The problem of downsizing of the speaker system and the accompanying deterioration of the low-frequency characteristics can be solved by separating the diaphragm of the speaker unit from the influence of braking by the air spring inside the enclosure. For example, musical instruments such as guitars and contrabass have good bass sound by the action of the resonance box, even though they have only very small surface area diaphragms such as strings. Also, harmonics that are harmonic components are extremely rich.

This is because the vibration of the string, which is the vibration element, is transmitted to the resonance box through the bridge, and the resonance of the body is maximally utilized. As is apparent from this example, the simplest and most efficient reproduction of bass sound by the speaker system is to use the enclosure as a resonance box.

Therefore, in the present invention, for example, by providing a predetermined ventilation path formed along substantially the entire inner periphery of the opening of the baffle plate and communicating with the inside and outside of the enclosure, at the outer periphery of the speaker unit, Do not attach the speaker unit to the baffle plate opening of the enclosure,
By installing it at a position away from the opening to the extent that low frequency characteristics do not deteriorate due to low frequency noise, the diaphragm is prevented from being affected by the air spring inside the enclosure, and the enclosure is efficiently used as a resonance box Use it.

Further, according to the present invention, there is provided a bass speaker unit in which a rib portion of a frame serving as a mounting surface to a baffle plate does not have a uniform ring shape, or a small-diameter, small-area mounting surface. In such a case, it is difficult to easily and accurately adjust a gap formed along substantially the entire inner periphery of the opening of the baffle plate between the rear surface of the outer peripheral portion of the speaker unit and the front surface of the baffle plate. Stretch low-frequency characteristics and improve sound quality in the entire frequency range.

Also, in the middle-tone speaker system and the high-tone speaker system, when the sound inside the enclosure is emitted from the surroundings to improve the sense of localization of the sound image, a large-diameter ring-shaped rim is used. By increasing the facing area between the rear or front surface of the outer peripheral portion and the front or rear surface of the baffle plate on the rear or front surface of the speaker unit, the resistance of air passing through the gap is appropriately adjusted, and low-frequency characteristics are improved. Prevent deterioration.

Next, an embodiment of a speaker system based on the basic concept of the present invention will be described. FIG. 1 is a longitudinal sectional view of the speaker system according to the first embodiment. In this figure, the speaker system is an enclosure 10
And a bass speaker unit 1 attached to an opening 12 of a baffle plate 11 on the front of the enclosure 10.
3 and a loudspeaker unit 15 for high / medium sound attached to the opening 14.

The bass speaker unit 13 has a predetermined ventilation which communicates the inside and outside of the enclosure 10 between the annular plate-shaped rim 16 attached to the rear surface of the flange 13A at the outer peripheral portion thereof and the front surface of the baffle plate 11. It is attached to the baffle plate 11 so as to form a gap that becomes a path.

In this embodiment, a plurality of tubular spacers 17 are interposed between the inner surface of the annular rim 16 at the rear surface of the flange portion 13A at the outer periphery of the bass speaker unit 13 and the front surface of the baffle plate 11. This spacer 1
The bass speaker unit 13 is attached to the baffle plate 11 by a screw 18 as a fixture inserted through the 7.

In this case, eight screw insertion holes are provided at regular intervals around the outer periphery of the flange portion 13A of the bass speaker unit 13, the annular rim 16 and the opening of the baffle plate 11, and the Through the speaker unit 13 side insertion hole, the ring-shaped rim 16 hole, the spacer 17 hole, and the baffle plate 11 side insertion hole, and the threaded end of the screw 18 protrudes from the back surface of the baffle plate 11. Nut 1
9 is fitted and tightened.

On the other hand, the treble / medium speaker unit 15 is provided between the inside and outside of the enclosure 10 between a ring-shaped rim 20 and a front surface of the baffle plate 11 which are attached to the rear surface of the flange 15A. Is attached to the baffle plate 11 so as to form a gap portion serving as a predetermined ventilation path communicating with the baffle plate 11.

In this embodiment, a plurality of tubular spacers are provided between the inner surface of the ring-shaped rim 20 at the rear position of the flange portion 15A on the outer periphery of the loudspeaker unit 15 for high / middle sound and the front surface of the baffle plate 11. The high / medium sound speaker unit 15 is attached to the baffle plate 11 with the screw 22 and the nut 23 inserted through the spacer 21 with the 21 interposed.

As the spacers 17 and 21, those made of a hard member such as a metal (vibration transmitting type), those made of an elastic member such as a rubber material or a coil spring (vibration absorbing type), and the like are used. In the case of the vibration absorbing type spacer, it is preferable to interpose a washer made of an elastic member such as a rubber material between the nuts 19 and 23 and the baffle plate 11. still,
In the figure, reference numeral 24A indicates a bass reflex port formed by the bass reflex duct 24.

FIG. 2 is a longitudinal sectional view of the speaker system according to the second embodiment. In this embodiment, the speaker unit 25 is mounted such that a gap of a predetermined distance is formed between the outer surface of the annular rim 26 at the front position of the flange portion 25A and the rear surface of the baffle plate 11. I have. That is, a plurality of tubular spacers 27 are interposed between a ring-shaped rim 26 attached to the front position of the flange portion 25A of the speaker unit 25 and the rear surface of the baffle plate 11, and screws 28 inserted into the spacers 27 are interposed. And the nut 29, the speaker unit 25 is connected to the baffle plate 11
It is designed to be attached to.

In each of the above-described embodiments, the spacers 17, 21, and 27 are provided with annular rims 16, 20, and 26, respectively.
Alternatively, it may be formed integrally with the baffle plate 11. For example, a spacer portion is integrally formed on the baffle plate 11 in advance, and the speaker units 13, 15, and
The annular rims 16, 20, 26 on the 25 side may be attached. For this attachment, rivets or split pins may be used. Alternatively, a pin and a C fitted into the pin
A ring may be used.

FIGS. 3A and 3B are a front view and a side view of a speaker unit of the speaker system according to the third embodiment. In this embodiment, the speaker unit 30 includes:
A ring-shaped rim 31, a plurality of spacers 32 projecting rearward from the rear surface of the ring-shaped rim 31, and a plurality of spacers 32 positioned rearward from the rear surface of the ring-shaped rim 31. A ring-shaped rib 33 connecting the spacers 32 is integrally formed, and the rib 33 is attached to the front surface of the baffle plate using screws and nuts.

Although not shown, a plurality of spacer portions projecting forward from the front surface of the ring-shaped rim portion, and a plurality of spacer portions projecting forward from the front surface of the ring-shaped rim portion on the speaker unit side. And a ring-shaped rib portion that connects the spacer portions with each other at a position in front of the baffle plate, and the rib portion may be attached to the back surface of the baffle plate using screws and nuts.

According to the speaker system having such a configuration,
By providing a predetermined ventilation path formed along the substantially entire inner periphery of the opening of the baffle plate and communicating with the inside and outside of the enclosure at the outer periphery of the speaker unit, the following operations and effects are achieved. That is, in the enclosure
The predetermined ventilation path communicating with the outside functions as a sound hole, and emits a resonance sound inside the enclosure by a bass reflex operation to enhance a bass range.

Further, the influence of the inertial vibration of the air spring in the enclosure on the diaphragm is reduced, the transient characteristics over the entire reproduction band are improved, and a sound quality that is stretchable and has no heavy weight can be obtained. Further, since the ventilation path is formed in the outer periphery of the speaker unit along substantially the entire inner periphery of the opening of the baffle plate, air uniformly enters and exits from the outer periphery of the speaker unit, and the cone of the speaker unit is formed. Because the curve of the paper is gradually formed toward the ventilation path, the air pressure inside the enclosure changes,
The resistance of the cone paper is effectively reduced, and the sound quality can be more effectively improved.

In particular, since the air passage is formed at a position close to the speaker unit along substantially the entire inner periphery of the opening of the baffle plate, the bass frequency characteristics are enhanced and
Disturbance in characteristics at other frequencies can be prevented.

Incidentally, when the air passages are not evenly located around the periphery of the speaker unit and there is a considerable distance, as described in the related art, the bass frequency characteristics can be enhanced, but the characteristics at other frequencies can be improved. There is a drawback that disturbance occurs. Therefore, even when the mounting capacity is smaller than the enclosure capacity required by the speaker unit, it is possible to suppress the attenuation of the low-frequency characteristics, and it is not necessary to use a large-diameter diaphragm, so that the enclosure capacity can be reduced. The speaker system can be downsized.

In particular, as a result of providing a ring-shaped rim for adjusting the facing area between the rear or front surface of the outer peripheral portion and the front or rear surface of the baffle plate, on the rear or front surface of the outer peripheral portion of the speaker unit. The following functions and effects are achieved.

In the case of a low-pitched speaker unit in which the rib portion of the frame serving as the mounting surface to the baffle plate does not have an even ring shape or has a small mounting surface area, the outer peripheral portion rear surface of the speaker unit may be used. In the case where the gap formed along substantially the entire inner periphery of the opening of the baffle plate between the front surface of the baffle plate and the baffle plate cannot be adjusted, a large-diameter annular plate-shaped rim is attached and the rear surface of the outer periphery of the speaker unit or By increasing the facing area between the rear surface or the front surface of the outer peripheral portion and the front surface or the rear surface of the baffle plate on the front surface, extension of low-frequency characteristics and improvement of sound quality in the entire region can be easily achieved.

That is, by adjusting the volume of the gap between the baffle plate and the ring-shaped rim by adjusting the area of the ring-shaped rim, the mass of the air passing through the gap is reduced. By controlling the resistance at the time of passing so that the diaphragm of the speaker unit can operate optimally, the amount of air exhausted / inhaled is added to the additional mass of the diaphragm, which has the effect of lowering the lowest resonance frequency. The air around the diaphragm is evenly and circumferentially discharged with appropriate resistance,
By inhaling, the force of the piston motion applied to the vicinity of the voice coil is transmitted to the periphery of the diaphragm in a well-balanced manner, preventing abnormal vibration of the diaphragm, lowering the enclosure stiffness, and preventing the Q of the voice coil from rising. , Effectively improving low frequency characteristics.

Further, in the middle-tone speaker system and the high-tone speaker system, when the sound inside the enclosure is emitted from the surroundings to improve the sense of localization of the sound image, a large-diameter ring-shaped rim is used. By increasing the area facing the rear or front surface of the outer peripheral portion and the front or rear surface of the baffle plate on the rear or front surface of the outer peripheral portion of the speaker unit, deterioration of low-frequency characteristics can be prevented.

That is, in the mid-range loudspeaker system and the high-range loudspeaker system, by adjusting the volume of the gap between the baffle plate and the ring-shaped rim, the mass of the air passing therethrough and the resistance of the air passing therethrough are reduced. This can prevent the low-frequency output of the entire speaker system from being reduced.

In this case, in any of the speaker units for bass, middle and treble, air is smoothly introduced and exhausted through the opening of the baffle plate.
For example, as in the fourth embodiment shown in FIG. 4, the surface of the opening 12 of the baffle plate 11 on the inner side of the enclosure 10 is largely counterbalanced (counterpart 12A) and opposed to the outer periphery of the speaker unit 13. It is preferable that the surface is rounded to be chamfered, and the rim 16 in the shape of an annular plate is provided so as to avoid the rectifying action of air passing through the minute gap, thereby preventing the occurrence of distortion.

As described above, by adding the ring-shaped rim, the rim is formed along the substantially entire inner circumference of the opening of the baffle plate between the rear surface of the outer peripheral portion of the speaker unit and the front surface of the baffle plate. As a result, it is possible to adjust the length of the ventilation path properly, thereby reducing the additional mass to the speaker unit diaphragm due to internal air when the enclosure does not have the required capacity of the woofer unit. It is possible to suppress the attenuation of the low-frequency reproduction characteristic, and it is particularly effective in a small speaker system in which the additional mass to the speaker unit diaphragm is easily reduced and the low-frequency reproduction characteristic is easily attenuated.

The gap serving as an air passage is provided between the inner surface of the annular rim on the speaker unit side and the front surface of the baffle plate, or between the outer surface of the annular rim and the rear surface of the baffle plate.
The embodiment formed by interposing a plurality of spacers has the following advantages.

That is, the spacer transmits the vibration of the frame of the speaker unit to the baffle plate, operates as if it were a bridge of a contrabass, and effectively vibrates the enclosure to increase the above-described resonance.
If the spacer is made of a material having a high vibration absorption rate, such as a resin such as rubber, or a small material such as a metal, the resonance of the baffle plate can be controlled according to the design intention.

Further, since ventilation holes can be formed in the outer periphery of the speaker unit by simple improvements such as adding a spacer, changing the shape of the opening of the baffle plate, changing the shape of the outer periphery of the speaker unit, etc. It is not necessary to use a specific specification, it can be easily applied to an existing speaker system, and the structure of the speaker unit does not become complicated, the weight does not increase, and the cost is advantageous.

Also, as shown in the embodiment of FIG. 1, a bus reflex port 24A provided by a bass reflex duct 24,
In the case where the bass radiating hole for the bass reflex is provided, the lowest frequency range can be made lower than that of a normal bass reflex type by setting the resonance frequency of the bass reflex port and the bass radiating hole as low as possible. Further, as in the embodiment of FIG.
According to the configuration in which the annular rim and the spacer are integrated with the speaker unit itself in advance, the number of parts can be reduced as an apparatus, and the present invention can be applied to a speaker system by attaching only the speaker unit. Therefore, it is also excellent in manufacturability.

According to the embodiment of the present invention, a speaker system provided in various kinds of audio equipment, in particular, an SR system,
The present invention can be applied to speaker systems for home audio, radio cassette players, karaoke machines, personal computers, televisions, and the like. In particular, when the speaker unit is built in a wall surface, an automobile door, or the like, the speaker unit may be attached to this attachment portion (which becomes a baffle plate) by the method of the above-described embodiment.

Further, in order to enhance the aesthetic appearance, the opening toward the outside of the ventilation path may be covered with a cloth having good ventilation. When the purpose is to reproduce a deep bass range, a resonance system may be further added to the speaker system in which the speaker unit is installed using the configuration of the present invention, and a low-frequency reproduction may be performed by adding a motional feedback or an equalizer operation. It is also possible to extend the limit frequency efficiently.

Here, the present inventors have proposed a speaker system (using a spacer and an annular rim) A-1 of the present invention based on the following specifications, and a conventional speaker system based on the following specifications. System (use only spacer) A-2
An experiment was conducted to compare the frequency characteristics of the conventional speaker system (without a spacer and a ring-shaped rim) A-3 (see the characteristic diagram of FIG. 5 showing experimental results).

(Specification of speaker system) A bass reflex type enclosure having an actual volume of 7.6 L (inner size H2
A ring-shaped rim is attached to a woofer unit (fo = 80HZ) having a hole diameter of 13 cm as a speaker unit at 6.7 cm × W16.4 cm × D17.3 cm, and a predetermined distance Rh (0.11 m) from a baffle plate by a spacer.
m) Install apart. The predetermined distance Rh was determined to be the most appropriate value by measuring frequency characteristics and impedance characteristics while hearing the music signal.

Further, as for the bass reflex duct, a normal bass reflex operation was performed so that Fo ′ = 55.05 Hz was obtained for the calculation and the experiment, and one pipe duct having an inner diameter of 2.9 cm × 7 cm was mounted on the back of the enclosure. The internal sound absorbing treatment was minimized to the extent that a rough hair felt having a thickness of about 5 mm was attached to the bottom inside the enclosure. In the characteristic diagram of FIG. 5, in the speaker unit (A-1) in which an acrylic ring-shaped rim having a diameter of 170 mm and a thickness of 3 mm is attached to the frame of the speaker unit, the low frequency range from 10 Hz to 42 Hz is low. The output is 1 db higher than that of the conventional bass reflex type speaker system (A-3) in which the unit is closely attached to the baffle. If the reproduction efficiency of the speaker system is low by 3 db, the output of the power amplifier to be driven needs to be doubled to obtain the same sound pressure, and this can be said to be an improvement of about 33% from the amplifier side.

In the case of the conventional loudspeaker system (A-2) having no ring-shaped rim, the low-frequency characteristics are deteriorated more than the loudspeaker system (A-3) in some bands. When a plate-shaped rim is mounted, the speaker system (A-
The low-frequency output did not fall below 3). Further, in the conventional bass reflex type, since the low tone is gradually lowered, f
o 'cannot be made as low as in the embodiment. However, in this experiment, the fo 'was set to 55.05 Hz lower than the fo' = 67 Hz product designed by the ordinary bass reflex design method under the same conditions, and +3 db in the range of 15 Hz to 35 Hz and 58 Hz to 79 Hz in the range of 15 Hz to 35 Hz. An improvement of +4 db was seen.

Further, the present inventors also conducted the following experiments. In the case of a two-way loudspeaker system to which the present invention is applied (the same applies to three-way and four-way loudspeaker systems), if not only the woofer but also the tweeter is not lifted, it is difficult to produce natural feeling such as timbre balance and sound of waves. If the tweeter is lifted and the sound of the woofer in the enclosure is emitted from around the tweeter, the sound is more localized. Therefore, in the prior application, the applicant simply mounted the tweeter away from the baffle plate.

However, in this case, the effect of the bass reflex duct was reduced due to air leakage around the tweeter, and the low frequency reproduction capability of the speaker system was reduced. Therefore, the configuration of the present invention, for example, a tweeter having a diameter of 80 mm and a thickness of 3 mm
According to the experimental results that adopts a configuration in which a very thin film (wrap, etc.) is used as a spacer and is screwed away from the baffle plate by about 0.01 mm, the same sound effect is used. Was obtained, and deterioration of characteristics in a low frequency range was prevented. Further, the peaks and valleys of the high frequency characteristics are reduced, and smoother characteristics are obtained.

The experimental results are shown in FIGS. 6 to 11, which are characteristic diagrams of the completed two-way speaker system models 1 to 3 of the present invention. FIG. 6 shows a tweeter with a diameter of 80 mm and a thickness of 3 mm.
Attached at 0.01 mm from the baffle plate using an acrylic ring-shaped rim with a woofer diameter of 1 mm.
FIG. 7 is a characteristic diagram of a model B-1 which is mounted at a distance of 0.11 mm from a baffle plate using an acrylic ring-shaped rim having a thickness of 70 mm and a thickness of 3 mm.

FIG. 7 is a characteristic diagram of a model B-2 in which an annular plate-shaped rim is used for only the woofer, and a tweeter is a model B-2 in which a conventional speaker unit and a baffle plate are in close contact. Model B, which is not in principle
As compared with the characteristic of -3, the same characteristic can be secured in the low frequency range, and the output increase and the flattening in the high frequency range are obtained.

FIG. 8 shows that the woofer uses an annular plate-shaped rim, the tweeter does not use the annular plate-shaped rim, and the speaker unit is mounted on a baffle plate via a washer having a thickness of 0.45 mm. The gap between the speaker unit and the baffle plate is a characteristic diagram of Model B-3 in which music is heard and the tone of a cymbal or the like is made to be the least turbid. Compared to the models B-1 and B-2, the low frequency range is greatly reduced (up to about 3 db). Also, the output and flattening of the high frequency band are inferior to the model B-1. That is, model B-
The characteristic of the model B-3 is that the effect of the ring-shaped rim attached to the tweeter used in 1 is effective.

Note that the characteristic diagram of FIG. 9 shows that the models B-1 and B-
3 is an enlarged view of the high-frequency characteristics of the model B-1, the characteristic diagram of FIG. 10 is an enlarged view of the high-frequency characteristics of the model B-1, and the characteristic diagram of FIG. 11 is an enlarged view of the high-frequency characteristics of the model B-3. It is.

[0061]

As described above, according to the first and third aspects of the present invention, a simple structure is formed on the outer periphery of the speaker unit along substantially the entire inner periphery of the opening of the baffle plate. While making the enclosure smaller and lighter, the bass range can be extended, the distortion can be reduced, the efficiency can be improved, and a high-quality sound speaker system with excellent transient characteristics and economy can be provided. The rear surface of the outer peripheral portion is provided with a ring-shaped rim for adjusting the facing area between the rear surface of the outer peripheral portion and the front surface of the baffle plate. Therefore, between the rear surface of the outer peripheral portion of the speaker unit and the front surface of the baffle plate. By adjusting the gap formed along almost the entire inner circumference of the opening of the baffle plate, the length of the ventilation path can be properly adjusted, and the air inside the enclosure is attached to the speaker unit diaphragm. It is possible to suppress the decrease in mass and suppress the attenuation of low-frequency reproduction characteristics, and it is particularly effective in a small speaker system in which the additional mass to the speaker unit diaphragm tends to decrease and the attenuation of low-frequency reproduction characteristics easily occurs. Become.

In particular, according to the second and fourth aspects of the present invention, the loudspeaker unit itself has a configuration in which the annular rim and the spacer are integrated in advance, so that the number of parts can be reduced as a device, and the loudspeaker can be reduced. Since the present invention can be applied to the speaker system by attaching only the unit, it is excellent in manufacturability.

[0063]

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a first embodiment of a speaker system according to the present invention.

FIG. 2 is a longitudinal sectional view of a second embodiment.

3A and 3B are diagrams showing a third embodiment, wherein FIG. 3A is a front view, and FIG. 3B is a side view.

FIG. 4 is a longitudinal sectional view showing a fourth embodiment.

FIG. 5 is a graph showing experimental results of frequency characteristics of the conventional speaker system and the speaker system of the present invention.

FIG. 6 is a graph showing experimental results of frequency characteristics of the speaker system of the present invention.

FIG. 7 is a graph showing experimental results of frequency characteristics of the speaker system of the present invention.

FIG. 8 is a graph showing experimental results of frequency characteristics of the speaker system of the present invention.

FIG. 9 is a graph showing experimental results of frequency characteristics of the speaker system of the present invention.

FIG. 10 is a graph showing experimental results of frequency characteristics of the speaker system of the present invention.

FIG. 11 is a graph showing experimental results of frequency characteristics of the speaker system of the present invention.

12A and 12B are longitudinal sectional views of a conventional speaker system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Enclosure 11 Baffle board 12 Opening 13 Low-pitched speaker unit 14 Opening 15 Treble / medium-tone speaker unit 16 Ring-shaped rim 17 Spacer 20 Ring-shaped rim 21 Spacer 25 Speaker unit 26 Ring-shaped -Shaped rim 27 Spacer 30 Speaker unit 31 Ring-shaped rim part 32 Spacer part 33 Rib part

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[Procedure amendment]

[Submission date] August 6, 1999 (1999.8.6)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

[Title of the Invention] Small speaker system

[Claims]

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to all small speaker systems using speakers, such as an SR system, a home audio speaker system, a speaker system suitable for a vehicle-mounted audio speaker system, etc. , and more particularly to an improvement in sound quality. Related technology.

[0002]

2. Description of the Related Art In a conventional loudspeaker system, generally, importance is placed on the hermeticity of an enclosure. this is,
This is because sound pressure leakage from the enclosure adversely affects the frequency characteristics. That is, the sound wave leaking from the enclosure interferes with the direct sound from the speaker system and disturbs the frequency characteristics. In particular, as the sound wave leaks from a portion farther from the speaker unit, the phase of the sound pressure in the enclosure is more likely to be uniform and sharper. Causes interference.

[0003] Therefore, it is an iron rule that a typical speaker unit is mounted on a baffle of an enclosure by keeping airtightness of its mounting surface, and this mounting method is treated in a textbook. For example, as shown in FIG. 12, the speaker unit 1 is attached with the inner surface of the flange 2 at the outer periphery thereof and the front surface of the baffle plate 4 of the enclosure 3 in close contact with each other.
The outer surface of the flange portion 2 and the rear surface of the baffle plate 4 are attached in close contact with each other.

[0004]

Generally, the low-frequency characteristics of a speaker system are limited to the lowest resonance frequency of the unit, and if the enclosure in which it is installed has sufficient capacity, the lowest resonance frequency of the unit is reduced. Although it is a condition for reproduction, in the conventional speaker system that emphasizes the tightness of the enclosure, the low frequency characteristics and transient of the speaker system are affected by the influence of the inertial vibration of the air spring inside the enclosure on the diaphragm. It adversely affects the characteristics, especially for small speakers
When the mounting capacity is smaller than the enclosure capacity required by the speaker unit in the system, the attenuation of the low-frequency characteristics becomes remarkable. In order to solve this problem, the present applicant has previously filed Japanese Patent Application No. 9-335004, which is formed around the entire inner circumference of the opening of the baffle plate at the outer periphery of the speaker unit, and A speaker system characterized by providing a predetermined ventilation path communicating with the speaker system.

However, it has been found that the effect of the proposed technique largely depends on the shape and area of the mounting rib of the speaker unit. In particular, in a small-sized speaker system in which the enclosure is reduced in size, the outer peripheral portion of the speaker unit is used. Adjust the minute gap formed along the substantially entire inner circumference of the opening of the baffle plate between the rear surface and the front surface of the baffle plate, and if the length of the ventilation path is not properly adjusted, the speaker unit due to the air inside the enclosure The mass added to the diaphragm is reduced, and the low-frequency reproduction characteristics are attenuated.

However, in the case of a low-pitched speaker unit in which a rib portion of a frame serving as a mounting surface to a baffle plate does not have a uniform ring shape, a small-diameter speaker unit having a small-diameter mounting surface area, It is not possible to adjust a minute gap formed along the substantially entire inner circumference of the opening of the baffle plate between the rear surface of the outer periphery of the speaker unit and the front surface of the baffle plate. For example, expansion of low-frequency characteristics, sound quality of the entire region Improvement cannot be achieved.

On the other hand, the composite midrange speaker units and tweeter units odor of the speaker system <br/> Te is to release enclosure internal sound from the surroundings, so as to improve the localization of the sound image and that although, rib portion of the frame as a mounting surface for a conventional baffle plate is small, due to the short length of the air passage facing area rather small the outer peripheral portion rear face and the baffle plate front face of the speaker unit, the low range characteristic Is likely to deteriorate.

The present invention has been made to solve the above-mentioned conventional problems. In a small speaker system, a simple improvement of a mounting structure of a speaker unit on a baffle plate of a speaker unit can reduce the size of the speaker system. While improving the low-frequency characteristics and transient characteristics of the speaker system while reducing the weight, especially along the substantially entire inner periphery of the opening of the baffle plate between the rear surface of the outer periphery of the speaker unit and the front surface of the baffle plate It is an object of the present invention to make it possible to easily and accurately adjust a minute gap formed by the above-described method, for example, to extend low-frequency characteristics and improve sound quality in the entire region.

[0009]

According to a first aspect of the present invention, there is provided a small-sized speaker system including an enclosure and a speaker unit attached to an opening of a baffle plate on a front surface of the enclosure. In the small speaker system, the speaker unit has a predetermined ventilation path formed along substantially the entire inner circumference of the opening of the baffle plate between the rear surface of the outer peripheral portion and the front surface of the baffle plate to communicate inside and outside the enclosure. The speaker unit is attached to the baffle plate so as to form a minute gap, and the rear surface of the outer peripheral portion of the speaker unit is provided with an increased facing area between the rear surface of the outer peripheral portion and the front surface of the baffle plate.
A ring-shaped rim for adjusting the height is provided.

According to a second aspect of the present invention, there is provided a speaker unit having a plurality of annular rims located on a rear surface of the speaker unit and a plurality of rims projecting rearward from the rear surface of the annular rim. And a ring-shaped rib portion located at a position rearward from the rear surface of the annular plate-shaped rim portion and connecting the spacer portions to each other were integrally formed, and the rib portion was attached to the front surface of the baffle plate. It is characterized by the following.

According to a third aspect of the present invention, there is provided a small speaker system including an enclosure and a speaker unit attached to an opening of a baffle plate on a front surface of the enclosure. The baffle is formed between the front surface and the rear surface of the baffle plate along a substantially entire inner periphery of the opening of the baffle plate so as to form a small gap portion serving as a predetermined ventilation path communicating between inside and outside of the enclosure. Attached to a plate, the front surface of the outer peripheral portion of the speaker unit is provided with an increased area of opposition between the front surface of the outer peripheral portion and the rear surface of the baffle plate.
A ring-shaped rim for adjusting the height is provided.

According to a fourth aspect of the present invention, there is provided a speaker unit having a plurality of annular rims located on the front surface of the speaker unit and a plurality of rims projecting forward from the front surface of the annular rim. And a ring-shaped rib portion located at a position forward of the front surface of the annular plate-shaped rim portion and interconnecting the spacer portions, were integrally formed, and the rib portion was attached to the rear surface of the baffle plate. It is characterized by the following.

The operation of the present invention will be described. In the invention according to claims 1 and 3, the predetermined air passage formed by the minute gap communicating between the inside and the outside of the enclosure functions as a sound hole, and the inside of the enclosure is provided.
Emits the resonance sound of the part, and also makes the enclosure smaller
Of the additional mass of the diaphragm of the speaker unit due to
The operation that the diaphragm receives due to the differential pressure between the atmospheric pressure and the cabinet internal pressure
It compensates for the increase in dynamic resistance and enhances the bass range. Further, the influence of the inertial vibration of the air spring inside the enclosure on the diaphragm is reduced, the transient characteristics over the entire reproduction band are improved, and a sound quality that is stretchable and has no heaviness is obtained.

Further, since the ventilation path is formed in the outer peripheral portion of the speaker unit along substantially the entire inner periphery of the opening of the baffle plate, air uniformly flows in and out from the outer peripheral portion of the speaker unit. Because the unit cone paper curves smoothly toward the ventilation path,
The resistance received by the cone paper due to the air pressure change inside the enclosure is effectively reduced, and the sound quality can be more effectively improved.

Further, since the air passage is formed at a position close to the speaker unit, it is possible to enhance the bass frequency characteristics and to prevent disturbance of the characteristics at other frequencies. And with the bass speaker unit,
If the rib of the frame that is the mounting surface to the baffle plate does not have an even ring shape, or if the mounting surface area is small, the baffle plate is placed between the rear surface of the outer periphery of the speaker unit and the front surface of the baffle plate. In the case where the minute gap formed along substantially the entire inner circumference of the opening cannot be adjusted,
A large-diameter annular plate-shaped rim is attached to the rear or front surface of the outer periphery of the speaker unit to increase the facing area between the rear or front surface of the outer periphery and the front or rear surface of the baffle plate, thereby improving ventilation.
By adjusting the length of the road, extension of low-frequency characteristics, improvement of sound quality in the entire region, and the like can be easily achieved.

Also, in the middle-tone speaker system and the high-tone speaker system, when the sound inside the enclosure is emitted from the surroundings to improve the sense of localization of the sound image, a ring-shaped rim having a large diameter is used. Attached to the rear or front surface of the outer periphery of the speaker unit, to increase the area of opposition between the rear or front surface of the outer periphery and the front or rear surface of the baffle plate ,
Adjusting the length of the air passage allows air to pass through
Low range characteristic imparted a large resistance can be prevented from being degraded.

In particular, in the inventions according to the second and fourth aspects, the number of parts is reduced as an apparatus by integrating the ring-shaped rim and the spacer in advance in the speaker unit itself. Since the present invention can be applied to the speaker system by only attaching the loudspeaker, the manufacturing efficiency is excellent.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the attached drawings. First, the basic concept of the present invention will be described. The problem of downsizing of the speaker system and the accompanying deterioration of the low-frequency characteristics can be solved by separating the diaphragm of the speaker unit from the influence of braking by the air spring inside the enclosure. For example, musical instruments such as guitars and contrabass have good bass sound by the action of the resonance box, even though they have only very small surface area diaphragms such as strings. Also, harmonics that are harmonic components are extremely rich.

This is because the vibration of the string, which is the vibration element, is transmitted to the resonance box through the bridge, and the resonance of the body is maximally utilized. As it is apparent from this example, the efficient reproduction in the most simple bass by the speaker system, it is necessary to use the enclosure as the resonance box.

Therefore, in the present invention, for example, by providing a predetermined ventilation path formed along substantially the entire inner periphery of the opening of the baffle plate and communicating with the inside and outside of the enclosure, at the outer periphery of the speaker unit, Do not attach the speaker unit to the baffle plate opening of the enclosure,
By installing it at a position away from the opening to the extent that low frequency characteristics do not deteriorate due to low frequency noise, the diaphragm is prevented from being affected by the air spring inside the enclosure, and the enclosure is efficiently used as a resonance box Use it.

Further, according to the present invention, there is provided a bass speaker unit in which a rib portion of a frame serving as a mounting surface to a baffle plate does not have a uniform ring shape, or a small-diameter, small-area mounting surface. in things like, of not difficult shape to easily and accurately adjust the clearance formed along the substantially entire inner periphery of the opening of the baffle plate between the outer peripheral portion rear face and the baffle plate front face of the speaker unit Speaker unit
For example, in a small-sized speaker system using the above, the extension of the low-frequency characteristic, the improvement of the sound quality of the whole area, and the like are intended.

Also, in the middle-tone speaker system and the high-tone speaker system, when the sound inside the enclosure is emitted from the surroundings to improve the sense of localization of the sound image, a large-diameter ring-shaped rim is used. By increasing the facing area between the rear or front surface of the outer peripheral portion and the front or rear surface of the baffle plate on the rear or front surface of the speaker unit, the resistance of air passing through the gap is appropriately adjusted, and low-frequency characteristics are improved. Prevent deterioration.

Next, an embodiment of a speaker system based on the basic concept of the present invention will be described. FIG. 1 is a longitudinal sectional view of the speaker system according to the first embodiment. In this figure, the speaker system is an enclosure 10
And a bass speaker unit 1 attached to an opening 12 of a baffle plate 11 on the front of the enclosure 10.
3 and a loudspeaker unit 15 for high / medium sound attached to the opening 14.

The bass speaker unit 13 has a predetermined ventilation which communicates the inside and outside of the enclosure 10 between the annular plate-shaped rim 16 attached to the rear surface of the flange 13A at the outer peripheral portion thereof and the front surface of the baffle plate 11. A fine road
It is attached to the baffle plate 11 so that a small gap is formed.

In this embodiment, a plurality of tubular spacers 17 are interposed between the inner surface of the annular rim 16 at the rear surface of the flange portion 13A at the outer periphery of the bass speaker unit 13 and the front surface of the baffle plate 11. This spacer 1
The bass speaker unit 13 is attached to the baffle plate 11 by a screw 18 as a fixture inserted through the 7.

In this case, eight screw insertion holes are provided at regular intervals around the outer periphery of the flange portion 13A of the bass speaker unit 13, the annular rim 16 and the opening of the baffle plate 11, and the Through the speaker unit 13 side insertion hole, the ring-shaped rim 16 hole, the spacer 17 hole, and the baffle plate 11 side insertion hole, and the threaded end of the screw 18 protrudes from the back surface of the baffle plate 11. Nut 1
9 is fitted and tightened.

On the other hand, the treble / medium speaker unit 15 is provided between the inside and outside of the enclosure 10 between a ring-shaped rim 20 and a front surface of the baffle plate 11 which are attached to the rear surface of the flange 15A. Is attached to the baffle plate 11 so as to form a minute gap portion serving as a predetermined ventilation path communicating with the baffle plate 11.

In this embodiment, a plurality of tubular spacers are provided between the inner surface of the ring-shaped rim 20 at the rear position of the flange portion 15A on the outer periphery of the loudspeaker unit 15 for high / middle sound and the front surface of the baffle plate 11. The high / medium sound speaker unit 15 is attached to the baffle plate 11 with the screw 22 and the nut 23 inserted through the spacer 21 with the 21 interposed.

As the spacers 17 and 21, those made of a hard material such as metal (vibration transmission type) are used.
You. In the case of plastic, rubber, etc.
Anything that can be kept. In the figure, the unexplained reference numeral 2
4A is a bass reflex port formed by the bass reflex duct 24.

FIG. 2 is a longitudinal sectional view of the speaker system according to the second embodiment. In this embodiment, the speaker unit 25 is mounted such that a minute gap of a predetermined distance is formed between the outer surface of the annular rim 26 at the front position of the flange portion 25A and the rear surface of the baffle plate 11. ing. That is, the flange portion 25 of the speaker unit 25
A A plurality of tubular spacers 27 are interposed between a ring-shaped rim 26 attached to the front position and the rear surface of the baffle plate 11, and a speaker unit is formed by screws 28 and nuts 29 inserted into the spacers 27. 25 is attached to the baffle plate 11.

In each of the above-described embodiments, the spacers 17, 21, and 27 are provided with annular rims 16, 20, and 26, respectively.
Alternatively, it may be formed integrally with the baffle plate 11. For example, a spacer portion is integrally formed on the baffle plate 11 in advance, and the speaker units 13, 15, and
The annular rims 16, 20, 26 on the 25 side may be attached. For this attachment, rivets or split pins may be used. Alternatively, a pin and a C fitted into the pin
A ring may be used.

FIGS. 3A and 3B are a front view and a side view of a speaker unit of the speaker system according to the third embodiment. In this embodiment, the speaker unit 30 includes:
A ring-shaped rim 31, a plurality of spacers 32 projecting rearward from the rear surface of the ring-shaped rim 31, and a plurality of spacers 32 positioned rearward from the rear surface of the ring-shaped rim 31. A ring-shaped rib 33 connecting the spacers 32 is integrally formed, and the rib 33 is attached to the front surface of the baffle plate using screws and nuts.

Although not shown, a plurality of spacer portions projecting forward from the front surface of the ring-shaped rim portion, and a plurality of spacer portions projecting forward from the front surface of the ring-shaped rim portion on the speaker unit side. And a ring-shaped rib portion that connects the spacer portions with each other at a position in front of the baffle plate, and the rib portion may be attached to the back surface of the baffle plate using screws and nuts.

According to the speaker system having such a configuration,
By providing a predetermined ventilation path formed along the substantially entire inner periphery of the opening of the baffle plate and communicating with the inside and outside of the enclosure at the outer periphery of the speaker unit, the following operations and effects are achieved. That is, in the enclosure
Predetermined ventilation paths that communicate with the outside function as sound holes , emit the resonance sound inside the enclosure, and
Vibration of speaker unit due to miniaturization of enclosure
Insufficient additional mass of the plate is determined by the difference between atmospheric pressure and cabinet internal pressure.
The supplementary bass range is enhanced by the increase in the movement resistance of the diaphragm caused by the vibration .

Further, the influence of the inertial vibration of the air spring in the enclosure on the diaphragm is reduced, the transient characteristics over the entire reproduction band are improved, and a sound quality that is stretchable and has no heavy weight can be obtained. Further, since the ventilation path is formed in the outer periphery of the speaker unit along substantially the entire inner periphery of the opening of the baffle plate, air uniformly enters and exits from the outer periphery of the speaker unit, and the cone of the speaker unit is formed. Because the curve of the paper is gradually formed toward the ventilation path, the air pressure inside the enclosure changes,
The resistance of the cone paper is effectively reduced, and the sound quality can be more effectively improved.

In particular, since the air passage is formed at a position close to the speaker unit along substantially the entire inner periphery of the opening of the baffle plate, the bass frequency characteristics are enhanced and
Disturbance in characteristics at other frequencies can be prevented.

Incidentally, when the air passages are not evenly located around the periphery of the speaker unit and there is a considerable distance, as described in the related art, the bass frequency characteristics can be enhanced, but the characteristics at other frequencies can be improved. There is a drawback that disturbance occurs. Accordingly, even when from the mounted volume is small enclosure volume required by the loudspeaker unit, it is possible to suppress the attenuation of the low frequency characteristics, the large-scale enclosures
Since the use of a loudspeaker becomes unnecessary, the capacity of the enclosure can be reduced, and the speaker system can be downsized.

In particular, as a result of providing a ring-shaped rim for adjusting the facing area between the rear or front surface of the outer peripheral portion and the front or rear surface of the baffle plate, on the rear or front surface of the outer peripheral portion of the speaker unit. The following functions and effects are achieved.

In the case of a low-pitched speaker unit in which the rib portion of the frame serving as the mounting surface to the baffle plate does not have an even ring shape or has a small mounting surface area, the outer peripheral portion rear surface of the speaker unit may be used. In the case where the gap formed along substantially the entire inner periphery of the opening of the baffle plate between the front surface of the baffle plate and the baffle plate cannot be adjusted, a large-diameter annular plate-shaped rim is attached and the rear surface of the outer periphery of the speaker unit or By increasing the facing area between the rear surface or the front surface of the outer peripheral portion and the front surface or the rear surface of the baffle plate on the front surface, extension of low-frequency characteristics and improvement of sound quality in the entire region can be easily achieved.

That is, by adjusting the area of the ring-shaped rim, the volume of the minute gap between the baffle plate and the ring-shaped rim is adjusted, and the mass of air passing through the minute gap is adjusted. And, by controlling the resistance when passing, so that the diaphragm of the speaker unit can operate optimally, the resistance force required for air discharge and suction is added to the additional mass of the diaphragm, and the lowest resonance frequency is reduced. By exerting the effect of lowering, the air around the diaphragm is discharged and sucked evenly and with appropriate resistance circumferentially, transmitting the force of the piston motion applied near the voice coil to the periphery of the diaphragm in a well-balanced manner To prevent abnormal vibration of the diaphragm and lower the enclosure's stiffness,
And effectively improve the low frequency characteristics.

Further, in the middle-tone speaker system and the high-tone speaker system, when the sound inside the enclosure is emitted from the surroundings to improve the sense of localization of the sound image, a large-diameter ring-shaped rim is used. At the rear or front of the outer periphery of the speaker unit, the opposing area between the rear or front of the outer periphery and the front or rear of the baffle plate is increased, thereby increasing the resistance of the air to be ventilated and deteriorating the low-frequency characteristics.
To be able to prevent.

That is, in the middle-tone speaker system and the high-tone speaker system, by adjusting the volume of the minute gap between the baffle plate and the ring-shaped rim, the mass of air passing therethrough and the amount of air passing therethrough can be reduced. The lowering of the low-frequency output of the entire speaker system can be prevented by the resistance.

In this case, in any of the speaker units for bass, middle and treble, air is smoothly introduced and exhausted through the opening of the baffle plate.
For example, as in the fourth embodiment shown in FIG. 4, the surface of the opening 12 of the baffle plate 11 on the inner side of the enclosure 10 is largely counterbalanced (counterpart 12A) and opposed to the outer periphery of the speaker unit 13. It is preferable that the surface is rounded to be chamfered, and the rim 16 in the shape of an annular plate is provided so as to avoid the rectifying action of air passing through the minute gap, thereby preventing the occurrence of distortion.

As described above, by adding the ring-shaped rim, the rim is formed along the substantially entire inner circumference of the opening of the baffle plate between the rear surface of the outer peripheral portion of the speaker unit and the front surface of the baffle plate. As a result, it is possible to adjust the length of the ventilation path properly by adjusting the minute gap part, and as a result, when the enclosure is less than the capacity required by the woofer unit, the additional mass to the speaker unit diaphragm due to internal air is reduced. And the attenuation of the low-frequency reproduction characteristics can be suppressed,
In particular, the present invention is effective in a small speaker system in which the additional mass to the speaker unit diaphragm is easily reduced and the low-frequency reproduction characteristic is easily attenuated.

It is to be noted that a plurality of minute gaps serving as ventilation paths are provided between the inner surface of the annular rim on the speaker unit side and the front surface of the baffle plate or between the outer surface of the annular rim and the rear surface of the baffle plate. The embodiment formed by interposing the spacer has the following advantages.

That is, the spacer transmits the vibration of the frame of the speaker unit to the baffle plate, operates as if it were a bridge of a contrabass, and effectively vibrates the enclosure to increase the above-described resonance.
If the spacers are formed of materials having different natural vibrations according to the design intention, the resonance of the baffle plate can be controlled.

Further, since ventilation holes can be formed in the outer periphery of the speaker unit by simple improvements such as adding a spacer, changing the shape of the opening of the baffle plate, changing the shape of the outer periphery of the speaker unit, etc. It is not necessary to use a specific specification, it can be easily applied to an existing speaker system, and the structure of the speaker unit does not become complicated, the weight does not increase, and the cost is advantageous.

Also, as shown in the embodiment of FIG. 1, a bus reflex port 24A provided by a bass reflex duct 24,
In the case where the bass radiating hole for the bass reflex is provided, the lowest frequency range can be made lower than that of a normal bass reflex type by setting the resonance frequency of the bass reflex port and the bass radiating hole as low as possible. Further, as in the embodiment of FIG.
According to the configuration in which the annular rim and the spacer are integrated with the speaker unit itself in advance, the number of parts can be reduced as an apparatus, and the present invention can be applied to a speaker system by attaching only the speaker unit. Therefore, it is also excellent in manufacturability.

According to the embodiment of the present invention, a speaker system provided in various kinds of audio equipment, in particular, an SR system,
The present invention can be applied to home audio speaker systems, radio cassette players, karaoke machines, personal computers, televisions, and other small speaker systems. In particular, when the speaker unit is built in a wall surface, an automobile door, or the like, the speaker unit may be attached to this attachment portion (which becomes a baffle plate) by the method of the above-described embodiment.

Further, in order to enhance the aesthetic appearance, the opening toward the outside of the ventilation path may be covered with a cloth having good ventilation. When the purpose is to reproduce a deep bass range, a resonance system may be further added to the speaker system in which the speaker unit is installed using the configuration of the present invention, and a low-frequency reproduction may be performed by adding a motional feedback or an equalizer operation. It is also possible to extend the limit frequency efficiently.

Here, the present inventors have proposed a speaker system (using a spacer and an annular rim) A-1 of the present invention based on the following specifications, and a conventional speaker system based on the following specifications. System (use only spacer) A-2
An experiment was conducted to compare the frequency characteristics of the conventional speaker system (without a spacer and a ring-shaped rim) A-3 (see the characteristic diagram of FIG. 5 showing experimental results).

(Specification of speaker system) A bass reflex type enclosure having an actual volume of 7.6 L (inner size H2
A ring-shaped rim is attached to a woofer unit (fo = 80HZ) having a hole diameter of 13 cm as a speaker unit at 6.7 cm × W16.4 cm × D17.3 cm, and a predetermined distance Rh (0.11 m) from a baffle plate by a spacer.
m) Install apart. The predetermined distance Rh (small gap)
Measured the frequency characteristic and the impedance characteristic while hearing the music signal, and determined the most appropriate values.

Further, as for the bass reflex duct, a normal bass reflex operation was performed so that Fo ′ = 55.05 Hz was obtained for the calculation and the experiment, and one pipe duct having an inner diameter of 2.9 cm × 7 cm was mounted on the back of the enclosure. The internal sound absorbing treatment was minimized to the extent that a rough hair felt having a thickness of about 5 mm was attached to the bottom inside the enclosure. In the characteristic diagram of FIG. 5, in the speaker unit (A-1) in which an acrylic ring-shaped rim having a diameter of 170 mm and a thickness of 3 mm is attached to the frame of the speaker unit, the low frequency range from 10 Hz to 42 Hz is low. The output is 1 db higher than that of the conventional bass reflex type speaker system (A-3) in which the unit is closely attached to the baffle. If the reproduction efficiency of the speaker system is low by 3 db, the output of the power amplifier to be driven needs to be doubled to obtain the same sound pressure, and this can be said to be an improvement of about 33% from the amplifier side.

In the case of the conventional loudspeaker system (A-2) having no ring-shaped rim, the low-frequency characteristics are deteriorated more than the loudspeaker system (A-3) in some bands. When a plate-shaped rim is mounted, the speaker system (A-
The low-frequency output did not fall below 3). Further, in the conventional bass reflex type, since the low tone is gradually lowered, f
o 'cannot be made as low as in the embodiment. However, in this experiment, the fo 'was set to 55.05 Hz lower than the fo' = 67 Hz product designed by the ordinary bass reflex design method under the same conditions, and +3 db in the range of 15 Hz to 35 Hz and 58 Hz to 79 Hz in the range of 15 Hz to 35 Hz. An improvement of +4 db was seen.

Further, the present inventors also conducted the following experiments. In the case of a two-way loudspeaker system to which the present invention is applied (the same applies to three-way and four-way loudspeaker systems), if not only the woofer but also the tweeter is not lifted, it is difficult to produce natural feeling such as timbre balance and sound of waves. If the tweeter is lifted and the sound of the woofer in the enclosure is emitted from around the tweeter, the sound is more localized. Therefore, in the prior application, the applicant simply mounted the tweeter away from the baffle plate.

However, in this case, the effect of the bass reflex duct was reduced due to air leakage around the tweeter, and the low frequency reproduction capability of the speaker system was reduced. Therefore, the configuration of the present invention, for example, a tweeter having a diameter of 80 mm and a thickness of 3 mm
According to the experimental results that adopts a configuration in which a very thin film (wrap, etc.) is used as a spacer and is screwed away from the baffle plate by about 0.01 mm, the same sound effect is used. Was obtained, and deterioration of characteristics in a low frequency range was prevented. Further, the peaks and valleys of the high frequency characteristics are reduced, and smoother characteristics are obtained.

The experimental results are shown in FIGS. 6 to 11, which are characteristic diagrams of the completed two-way speaker system models 1 to 3 of the present invention. FIG. 6 shows a tweeter with a diameter of 80 mm and a thickness of 3 mm.
Attached at 0.01 mm from the baffle plate using an acrylic ring-shaped rim with a woofer diameter of 1 mm.
FIG. 7 is a characteristic diagram of a model B-1 which is mounted at a distance of 0.11 mm from a baffle plate using an acrylic ring-shaped rim having a thickness of 70 mm and a thickness of 3 mm.

FIG. 7 is a characteristic diagram of a model B-2 in which an annular plate-shaped rim is used for only the woofer, and a tweeter is a model B-2 in which a conventional speaker unit and a baffle plate are in close contact. Model B, which is not in principle
As compared with the characteristic of -3, the same characteristic can be secured in the low frequency range, and the output increase and the flattening in the high frequency range are obtained.

FIG. 8 shows that the woofer uses an annular plate-shaped rim, the tweeter does not use the annular plate-shaped rim, and the speaker unit is mounted on a baffle plate via a washer having a thickness of 0.45 mm. The gap between the speaker unit and the baffle plate is a characteristic diagram of Model B-3 in which music is heard and the tone of a cymbal or the like is made to be the least turbid. Compared to the models B-1 and B-2, the low frequency range is greatly reduced (up to about 3 db). Also, the output and flattening of the high frequency band are inferior to the model B-1. That is, model B-
The characteristic of the model B-3 is that the effect of the ring-shaped rim attached to the tweeter used in 1 is effective.

Note that the characteristic diagram of FIG. 9 shows that the models B-1 and B-
3 is an enlarged view of the high-frequency characteristics of the model B-1, the characteristic diagram of FIG. 10 is an enlarged view of the high-frequency characteristics of the model B-1, and the characteristic diagram of FIG. 11 is an enlarged view of the high-frequency characteristics of the model B-3. It is.

[0061]

As described above, according to the first and third aspects of the present invention, the enclosure is provided along the substantially entire inner periphery of the opening of the baffle plate at the outer periphery of the speaker unit.
-With a simple structure that forms a minute gap that serves as a predetermined ventilation path that communicates inside and outside, while making the enclosure smaller and lighter, while expanding the bass range, reducing distortion, It is possible to provide a speaker system of high sound quality which can achieve high efficiency and is excellent in transient characteristics and economical efficiency. In particular, in the rear surface of the outer peripheral portion of the speaker unit, the facing area between the rear surface of the outer peripheral portion and the front surface of the baffle plate is adjusted. To adjust the minute gap formed between the rear surface of the outer periphery of the speaker unit and the front surface of the baffle plate along substantially the entire inner circumference of the opening of the baffle plate. As a result, the length of the ventilation path can be properly adjusted, the reduction of the additional mass to the speaker unit diaphragm due to the air inside the enclosure can be suppressed, and the attenuation of the low-frequency reproduction characteristics can be suppressed. Easy reduction of the added mass of the moving plate occurs,
This is effective in a small loudspeaker system in which the attenuation of low-frequency reproduction characteristics is likely to occur.

In particular, according to the second and fourth aspects of the present invention, the loudspeaker unit itself has a configuration in which the annular rim and the spacer are integrated in advance, so that the number of parts can be reduced as a device, and the loudspeaker can be reduced. Since the present invention can be applied to the speaker system by attaching only the unit, it is excellent in manufacturability.

[0063]

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a first embodiment of a speaker system according to the present invention.

FIG. 2 is a longitudinal sectional view of a second embodiment.

3A and 3B are diagrams showing a third embodiment, wherein FIG. 3A is a front view, and FIG. 3B is a side view.

FIG. 4 is a longitudinal sectional view showing a fourth embodiment.

FIG. 5 is a graph showing experimental results of frequency characteristics of the conventional speaker system and the speaker system of the present invention.

FIG. 6 is a graph showing experimental results of frequency characteristics of the speaker system of the present invention.

FIG. 7 is a graph showing experimental results of frequency characteristics of the speaker system of the present invention.

FIG. 8 is a graph showing experimental results of frequency characteristics of the speaker system of the present invention.

FIG. 9 is a graph showing experimental results of frequency characteristics of the speaker system of the present invention.

FIG. 10 is a graph showing experimental results of frequency characteristics of the speaker system of the present invention.

FIG. 11 is a graph showing experimental results of frequency characteristics of the speaker system of the present invention.

12A and 12B are longitudinal sectional views of a conventional speaker system.

DESCRIPTION OF SYMBOLS 10 Enclosure 11 Baffle plate 12 Opening 13 Bass speaker unit 14 Opening 15 Treble / medium speaker unit 16 Ring-shaped rim 17 Spacer 20 Ring-shaped rim 21 Spacer 25 Speaker Unit 26 Ring-shaped rim 27 Spacer 30 Speaker unit 31 Ring-shaped rim 32 Spacer 33 Rib

Claims (4)

[Claims] 1. A speaker system comprising: an enclosure; and a speaker unit attached to an opening of a baffle plate on a front surface of the enclosure. The speaker unit is attached to the baffle plate so that a gap is formed along substantially the entire inner circumference of the opening of the baffle plate and serves as a predetermined ventilation path communicating between inside and outside of the enclosure. A speaker system comprising: a ring-shaped rim provided on a rear surface of an outer peripheral portion for adjusting a facing area between the rear surface of the outer peripheral portion and a front surface of a baffle plate. 2. An outer peripheral portion of the speaker unit, a ring-shaped rim located on a rear surface of the outer peripheral portion, a plurality of spacers projecting rearward from a rear surface of the ring-shaped rim, and a circle. A ring-shaped rib portion which is located at a position rearward from the rear surface of the ring-shaped rim portion and connects the spacer portions to each other; Item 7. The speaker system according to Item 1. 3. A speaker system comprising: an enclosure; and a speaker unit attached to an opening of a baffle plate on a front surface of the enclosure, wherein the speaker unit is connected to a front surface of an outer peripheral portion and a rear surface of the baffle plate. The speaker unit is attached to the baffle plate so that a gap is formed along substantially the entire inner circumference of the opening of the baffle plate and serves as a predetermined ventilation path communicating between inside and outside of the enclosure. A speaker system comprising: a ring-shaped rim provided on an outer peripheral front surface for adjusting a facing area between the outer peripheral front surface and a rear surface of a baffle plate. 4. An outer peripheral portion of the speaker unit, an annular plate-shaped rim located on the front surface of the outer peripheral portion, a plurality of spacer portions protruding forward from the front surface of the annular plate-shaped rim portion, and an annular ring. A ring-shaped rib portion which is located at a position forward from the front surface of the plate-shaped rim portion and connects the spacer portions to each other;
The speaker system according to claim 3, wherein the rib portion is attached to a rear surface of the baffle plate.