JPH0813159B2 - Speaker device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker device in which an acoustic tube for guiding sound waves is arranged on the front surface of a speaker unit.

Conventional technology A horn and an acoustic tube are installed on the front of the speaker unit,
The method of guiding the sound wave generated from the diaphragm to the opening has the advantage that the output sound pressure can be obtained larger and the sound can be transmitted in a specific direction compared to the case where no horn or acoustic tube is used. Many are used.

Hereinafter, a conventional speaker device using a horn and an acoustic tube will be described with reference to the drawings.

FIG. 6 shows a sectional view of the speaker device. In FIG. 6, 1 is a speaker unit, 2 is a baffle plate to which the speaker unit 1 is attached, 3 is a rear surface box provided on the back surface of the speaker unit 1, and 4 is provided on the front surface of the baffle plate 2 to which the speaker unit 1 is attached. Acoustic tube,
Reference numeral 5 is a sound guide portion constituted by the acoustic tube 4. The operation of the speaker device having the horn and the acoustic tube configured as described above will be described below with reference to FIG. FIG. 7 is a perspective view of the acoustic tube section showing the configuration of the acoustic tube section in a partial sectional view. The hole 6 provided at the center of the baffle plate 2 is a hole for guiding the sound wave radiated from the speaker unit 1 to the sound conducting section 5 of the acoustic tube 4, and the acoustic tube 4 is a baffle dimension on the front surface of the speaker unit 1. L1 and baffle area is small,
The acoustic tube opening size L2 and the acoustic tube cross-sectional area gradually increase as the distance from the opening of the acoustic tube 4 approaches. If the length L3 of the acoustic tube 4 is sufficiently longer than the wavelength of the reproduction band to be reproduced, the reproduced sound pressure frequency characteristic is flat.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in order to be incorporated in a device with the above-mentioned configuration, it is often not possible to sufficiently lengthen the acoustic tube, and the acoustic tube opening cross-sectional area is compared to the baffle area in front of the speaker unit. In many cases, it cannot be taken large enough.

For example, FIG. 8 is a perspective view of an acoustic tube portion in which the acoustic tube opening has a long and thin rectangular shape in consideration of incorporation into a device.
L4 indicates the size of the rectangular side of the acoustic tube opening. Compared to the baffle dimension L1 on the speaker unit mounting surface, L4 is the acoustic tube opening dimension L4.
Is small, even if the area of the acoustic tube opening is larger than the area of the baffle on the front surface of the speaker unit, the acoustic section 5 often has a structure in which the acoustic section 5 is once narrowed on the way from the front surface of the speaker unit to the acoustic tube opening. That is, since the acoustic tube cross-sectional area is once reduced, one acoustic space is formed in the front surface of the speaker unit, and the acoustic tube 4 is attached to the tip of the acoustic space. FIG. 9 shows a reproduced sound pressure frequency characteristic diagram of a speaker device having a horn and an acoustic tube. The characteristic A in the figure is a characteristic diagram of the speaker device with the conventional horn and the acoustic tube shown in FIG. 6, and the characteristic B in the figure is the speaker apparatus in the case of the acoustic tube shape shown in FIG. Is a characteristic of. In the case of the acoustic tube shape shown in FIG. 8, one acoustic space formed on the front surface of the speaker unit acts as the compliance C, so that the high frequency characteristic is reduced as shown in the characteristic of FIG. 9B, and further, the acoustic tube length is reduced. Since it becomes a short state, the change in the acoustic impedance generated in the opening of the acoustic tube becomes large, and part of the sound wave guided to the opening is generated inside the acoustic tube as a reflected wave, resulting in characteristics with many peaks and dips. . Further, in the case of the conventional speaker device having the above-mentioned configuration, the high frequency characteristic is reduced, so that it is necessary to use a tweeter in charge of high frequency reproduction as the sound reproducing device.

The present invention solves such a problem, and even in a speaker device having a horn or an acoustic tube whose opening is an elongated rectangular shape in consideration of incorporation into a device, there is little decrease in high-frequency characteristics, and the peak value is further reduced. The object of the present invention is to provide a speaker device capable of obtaining a flat sound pressure frequency characteristic without dips.

Means for Solving the Problem In order to solve the problem, the present invention arranges an acoustic tube for guiding a sound wave having a long and narrow opening in a front surface of a speaker unit. The front surface has a small area, and the area increases toward the opening, and the speaker unit has a rectangular cone-shaped diaphragm, and the speaker unit also has a rectangular shape. The arrangement is such that the long side direction of the opening and the long side direction of the rectangular speaker unit are aligned.

Operation With this configuration, a rectangular speaker unit having a rectangular cone-shaped diaphragm is used even in a speaker device having a horn or an acoustic tube whose opening has a long and narrow rectangular shape in consideration of incorporation into equipment. At the same time, by arranging so that the long side direction of the speaker unit and the long side direction of the acoustic tube opening match.
Since the area of the front surface of the speaker unit can be made small, the acoustic space acting as the compliance C on the front surface of the speaker unit can be made very small, and the area of the sound portion can be made larger from the front surface of the speaker unit toward the opening. Without changing the shape and the length of the horn and the acoustic tube, it is possible to obtain flat sound pressure frequency characteristics with less decrease in the high frequency characteristic and less peaks and dips. Only the speaker device is in charge of high frequency reproduction. The sound reproducing device can be satisfied without the need to use a tweeter or the like together.

Embodiments Embodiments of the present invention will be described below with reference to the drawings. The same reference numerals as those in FIGS. 6 to 9 indicate the same parts.

FIG. 4 is a perspective view of the acoustic tube portion in one embodiment of the present invention. In FIG. 4, 7 is a baffle plate for mounting a rectangular speaker unit having a hole for guiding the sound wave radiated from the speaker unit to the acoustic tube 4, and 5 is a sound guide part for guiding the sound wave whose opening is rectangular. The area of the sound guide portion 5 is small on the front surface of the speaker unit, and the area increases as it approaches the opening. FIG. 5 is a front view showing a state in which the rectangular speaker unit 8 is attached to the baffle plate 7 which constitutes the acoustic tube portion of the present invention shown in FIG.

The operation of the speaker device having the acoustic tube portion of the present invention configured as described above will be described with reference to FIGS. 1 to 3.

FIG. 1 is a cross-sectional view of an open rear type speaker device having an acoustic tube portion according to an embodiment of the present invention, and FIG. 2 is a rectangular speaker unit composed of the cone-type diaphragm shown in FIG. FIG. 3 is a diaphragm cross-sectional view showing the shape of the diaphragm in the XX section, and FIG. 3 is a diaphragm cross-sectional view showing the rectangular speaker unit constituted by the cone-shaped diaphragm in the YY section.

In the speaker device of FIG. 1, the shape of the diaphragm 9 of the rectangular speaker unit 8 attached to the baffle plate 7 is different between the long side direction and the short side direction as shown in FIGS. 2 and 3. In addition, by arranging so that the long side direction of the opening of the acoustic tube 4 and the long side direction of the rectangular speaker unit 8 coincide with each other, the standing wave generated inside the acoustic tube 4 is suppressed. It is possible to obtain flat sound pressure frequency characteristics with few peaks and dips. Further, particularly by using the rectangular speaker unit 8, it is possible to increase the radiation area of the sound conducting portion 5 as the front surface of the rectangular speaker unit 8 approaches the opening.
The acoustic space acting as the compliance C on the front surface of the rectangular speaker unit 8 can be reduced, and further, unlike the axisymmetric shape of the diaphragm of the conventional round speaker unit, each surface constituting the diaphragm 9 has a long side direction and a short side direction. Due to the difference in the direction, not only the sound pressure peripheral number characteristic with little reduction in the high frequency characteristic but also the directivity characteristic on the left and right in the long side direction of the opening is less reduced.

As described above, according to the present embodiment, the rectangular speaker unit 8 is provided in the acoustic tube 4 configured such that the area of the front surface of the speaker unit is small and the area of the front surface of the speaker unit becomes larger toward the opening. The sound wave can be naturally guided to the opening of the tube 4 without resistance, flat characteristics can be obtained even in a high frequency region, and a speaker device with high clarity can be realized.

In addition, although the rear surface is open in FIG. 1 in one embodiment, it is needless to say that the same effect can be obtained in the case of a closed type and a bass reflex type speaker device.

EFFECTS OF THE INVENTION As described above, according to the present invention, an acoustic tube for guiding a sound wave having a rectangular opening is disposed on the front surface of the speaker unit,
This acoustic tube has a small area on the front surface of the speaker unit and has a larger area as it approaches the opening, and the speaker unit has a rectangular shape. By arranging so that the long side direction of the speaker unit coincides with the direction of the long side, even in a speaker device in which the acoustic tube opening has a long and thin rectangular acoustic tube in consideration of incorporation into a device, the speaker unit front face The acoustic space acting as the compliance C can be made small, and the area of the sound conducting section can be naturally increased without any resistance as the front side of the speaker unit approaches the opening, so that flat sound with less peak and dip is reduced in high frequency characteristics. Pressure frequency characteristics are obtained,
Consequently, it is possible to obtain an effect that a speaker device with good clarity can be obtained without using a tweeter or the like together.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a rear open speaker device having an acoustic tube portion according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing a diaphragm shape of a rectangular speaker unit in the long side direction, and FIG. Rectangular speaker unit Sectional view showing the shape of a diaphragm in the short side direction, FIG. 4 is a perspective view of an acoustic tube portion according to an embodiment of the present invention, and FIG. 5 is a front view of an acoustic tube portion according to an embodiment of the present invention. 6 and 6 are cross-sectional views of a speaker device having a conventional horn and an acoustic tube, and FIG. 7 is a perspective view of the acoustic tube section showing a partial cross-sectional view of the configuration of the conventional acoustic tube section shown in FIG. FIG. 8 is a perspective view of a conventional acoustic tube portion in which the acoustic tube opening has an elongated rectangular shape, and FIG. 9 is a characteristic diagram of a speaker device having a horn and an acoustic tube. 4 ... Acoustic tube, 5 ... Sound conducting part, 7 ... Baffle plate, 8 ...
... rectangular speaker unit, 9 ... diaphragm.

Claims (1)

[Claims] 1. An acoustic tube for guiding a sound wave having an elongated rectangular shape is arranged on the front surface of a speaker unit. The acoustic tube has a small area on the front surface of the speaker unit and becomes closer to the opening. In order to increase the area, the speaker unit is configured to have a rectangular cone-shaped diaphragm, the speaker unit is also rectangular, and the long side direction of the acoustic tube opening and the rectangular speaker unit. A speaker device configured to be arranged so that the direction of the long side thereof coincides.