JPS5856940A - Speaker on board car - Google Patents

Abstract

PURPOSE:To make a car-loading speaker compact and improve its tone quality by arranging a number of plane wave plane driving type speakers almost in the same plane adjacently, connecting them in parallel, constituting a single speaker unit, and arranging the required number of speaker units. CONSTITUTION:Circular holes are provided on the plate 11 of a sun visor 1 and a number of plane wave plane driving type speakers SP1 to SP8 are mounted on them. A flexible cushion material 13 is arranged between the plate 11 and a cover 12. Besides, this speaker unit is mounted on the right and left sun visors 1 in a car as a stereo unit. As a result, since sound comes from the front of hearers, the position of a sound source is not unnatural. Further, since the tone quality caused by the excessive inclination of the speaker for the hearers is not deteriorated and sound is produced from both the front and rear of the speaker, the tone quality is not deteriorated even the sun visors are inclined.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle-mounted speaker whose acoustic characteristics are completely improved using a plane wave plane drive type speaker.

Because there are restrictions on where all the speakers can be installed inside a car, conventionally, cone-shaped speaker trays, doors,
It is generally installed on the front nozzle, etc. [7
However, in this case, there are the following problems. (1) If the mounting part is a door or front panel, the depth dimension will be limited, so why not install the speaker? It has to be made thinner, which causes distortion in the sound and deteriorates the sound quality. (2) In the case of the installation described in (1) above, the tilt of the speaker with respect to the listener becomes too large, and the sound quality mainly at high frequencies deteriorates due to the directional characteristics of the speaker. (3) If the mounting section is rear tom V, when listening to music, although it is natural for the sound to come from the front, there is an unnatural feeling that the sound comes from the rear.

(4) If the enclosure is mounted on a door or front panel, it will not be possible to secure the full volume of the enclosure, resulting in a lack of bass. (5) Although all installation parts are common, it is difficult to design the buckle plate and enclosure part with acoustically optimum materials and dimensions, which tends to deteriorate the sound quality.

The above-mentioned problems are due to the fact that the conventional vehicle-mounted speaker is cone-shaped, and its thickness restricts the mounting location, and that it is basically a point sound source.

The present invention attempts to solve the above-mentioned problems by using a plane wave plane drive type speaker.The present invention is characterized by the fact that a plurality of plane wave plane drive type speakers are all disposed close to each other in substantially the same plane. , and these speakers are connected in parallel and series to form one speaker unit, and all the required number of speaker units are arranged at appropriate locations in the automobile. This will be explained in detail below with reference to all illustrated embodiments.

FIG. 1 shows an embodiment of the present invention in which the mounting point is a sun visor of an automobile. The illustrated sun visor 1 is a sunshade provided on each side above a windshield in an automobile, and is supported by a hollow tube body 2 and is rotatable.

The sun visor 1 of this example has a hard plate 11 made of resin or the like, whose surface is covered with a thin flexible cover 12, and inside the sun visor 1 are a plurality of (eight in this example) small and thin plane wave plane drive type speakers 81''+ -8Pgk embedded, that is, plate 11
8 circular holes are provided in the speakers SP1 to SP+.
+'e Attach. A flexible cushioning material 13 is interposed between the plate 11 and the cover 12. However, holes are made in the cushioning material 13 at locations corresponding to the installation locations of the speakers SP1 to SP8 so as not to reduce the overall acoustic effect.

FIG. 2 is a diagram illustrating a single plane-wave plane-type flat panel.

This speaker is roughly divided into a mounting collar part 20 and a cylindrical main body part 21 in appearance. The dimensions of each part are, for example, the length and width of the collar part 20 are Wl = = W2 = 50 III +,
Regarding the main body part 21, diameter φ=39+m, thickness t;
It is as small and thin as 12 centimeters, and its total weight is only 5.
Light at 0g. In terms of electrical characteristics, the input impedance is 8Ω, and the output sound pressure is 86dB/W-m.

Rated human power is 20W.

To make eight speakers SPI to SP8 into one speaker unit as shown in FIG. 1, they are connected in parallel and in series as shown in FIG. 3, for example. knob, vertically adjacent speaker pair (SPl, 5
Pz), (SPs, 5P4)・Song (SPY.

5Ps)Th Connect in parallel to form all 4 speaker groups of 40 each, then connect 2 groups of these in parallel to form 2 speaker groups of 20 each, and finally connect them all in series. A total of 8 speakers with an input impedance of 4Ω) are configured as SPUi.

The connection method is not necessarily limited to this, and a parallel-series connection with a total impedance of 8Ω is also possible.

Figure 4 is a characteristic diagram of such a plane wave plane drive type speaker.
(a) is a characteristic diagram of a single unit. In this case, it has tweeter-like characteristics, and the reproduction frequency band is! 1KH2 to 50KHz, and the low frequency characteristics are insufficient. The present invention attempts to extend the low-frequency characteristics as a plane sound source by using a plurality of plane wave plane drive type speakers as a set. (b)
is a characteristic diagram when four speakers are arranged in a row, and the lower limit of the reproduction frequency band extends to 8 degrees of IKHz. (c)
is a characteristic diagram when all 16 speakers are arranged in two rows of 8 each, and the lower limit of the reproduction frequency band is extended to K below 500 Hz.

The characteristics of the embodiment shown in FIG. 1 are between those shown in FIG. Because of its large size, it is impossible to attach it to thin areas such as sun visors. In addition, when the sun visor 1 is installed at a location, the wiring between the speakers sp, to SPs and an amplifier (not shown) may be routed through the hollow support tube 2. Also, sun visor 1
Since there is a pair of left and right speakers, in the case of stereo reproduction, two sets of speaker units SPU' for R reproduction and L reproduction may be separately attached to the respective sun visors.

As described above, since the in-vehicle speaker of the present invention uses a plane-wave plane drive type speaker, it can be installed anywhere even in a limited space in a car. Moreover, unlike a cone-type speaker, a plane wave drive type speaker does not deteriorate in sound quality even if it is downsized for installation. Furthermore, due to miniaturization, the frequency band of sound that can be generated by a single button tends to become narrower, but by mounting the button at multiple points, the frequency band can be widened.

In the embodiment, the sun visor was mounted on the gold side, but it may be mounted anywhere, such as on the ceiling or on the front panel.

However, when attached to a sun visor, (1) the sound comes from in front of the listener, so the position of the sound source does not appear unnatural;
2) The sound quality does not deteriorate due to the speaker being tilted too far in relation to the listener. (6) Since plane wave plane drive speakers generate alloys from both the front and back sides, the sound quality will not deteriorate even if the sun visor is tilted. There are advantages such as:

[Brief explanation of the drawing]

Figures 1(a) and 1(b) are a front view and a side sectional view showing an embodiment of the present invention; Figures 2(a) and 2(b) are a front view and a side view showing a plane wave plane drive type speaker alone; FIG. 3 is an equivalent circuit diagram showing a wiring example of the speaker unit of FIG. 1, and FIG. 4 is a frequency characteristic diagram of plane wave plane drive type speakers alone and in combination. In the figure, 1 is a sun visor, and SP1 to SPs are plane wave plane drive type speakers. Applicant Fujitsu Ten Ltd. Representative Patent Attorney Minoru Seyanagi 257-

Claims (2)

[Claims] (1) A plurality of plane wave plane drive type speakers are disposed close to each other in substantially the same plane, and these speakers are connected in parallel and series to form one speaker unit l'', and the total number of speaker units required is within a car. An in-vehicle speaker that has all the characteristics of being placed in the right place. (2) An in-vehicle speaker according to claim 1, characterized in that two speaker units are attached to left and right sun visors in an automobile for stereo use.