JP3202220B2 - Rear tray speaker system for vehicles - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a rear tray speaker system for a vehicle.

[Conventional technology]

Conventionally, as a vehicle-mounted rear speaker system,
The one shown in FIG. 12 is known. In each of the drawings, 41 is a rear seat, 42 is a rear tray board that separates a trunk room and a passenger compartment, and 43 is a rear tray board 42.
It is a sideboard that supports

The rear speaker system in Fig. 9 has left and right sideboards.
43 has a speaker unit 44 embedded therein, the rear speaker system of FIG. 10 has a speaker unit 45 embedded on a rotatable rear tray board 42 in a two-box car or the like, and the rear speaker system of FIG. A stationary speaker unit 46 is mounted on a rear tray board 42 in a car or the like.The rear speaker system shown in FIG. 12 includes a box type 3D woofer system 48 for heavy bass reproduction in a trunk room 47 below the rear tray board 42. It was installed.

[Problems to be solved by the invention]

In the case of the rear speaker system of FIGS. 9 and 10,
Because it is difficult to completely seal the rear tray 42 and the sideboard 43 that separate the trunk room and the cabin,
It is difficult to obtain a perfect baffle effect. Further, in the case of the speaker system shown in FIGS. 9 to 11, it is difficult to install a large-diameter speaker due to its structure, and it is difficult to reproduce heavy bass which is often insufficient in a vehicle. Further, in the case of the rear speaker system shown in FIG. 12, a large volume speaker box is required, so that there is a problem that the space in the trunk room is considerably sacrificed.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an in-vehicle rear tray speaker system that can reproduce heavy bass while using a relatively small-diameter speaker. .

[Means for solving the problem]

In order to achieve the above object, a flat and thin back cavity portion formed of a closed space covering the rear tray board back surface is formed on the back surface of the first in-vehicle rear tray board, and at an appropriate position on the front surface of the rear tray board, the back cavity portion is provided. Two holes communicating with each other are bored, and a speaker is embedded and installed in one of the openings toward the vehicle interior,
By partitioning the inside of the back cavity portion between the rear surface of the rear tray board and the surface facing the rear surface of the rear tray board with a partition wall, an acoustic resonance path of a predetermined length connecting the other of the openings and the rear surface of the speaker is formed.

The second in-vehicle rear tray speaker system includes:
A flat and thin back cavity portion formed of a closed space covering the rear tray board back surface is formed on the back surface of the rear tray board, and a speaker is installed in the back cavity portion in a direction perpendicular to the rear tray board, and the rear tray board has At the appropriate position on the surface, two independent openings communicating with the back cavity are formed.
By partitioning the inside of the back cavity portion between the rear tray board back surface and the surface facing the rear tray board back surface by a partition wall, acoustic resonance connecting one of the openings to the speaker front surface and the other of the openings to the speaker back surface, respectively. Form a road.

(Operation)

In the case of the first in-vehicle rear tray speaker system, the reproduced sound from the front of the speaker is directly radiated into the vehicle interior. On the other hand, the reproduced sound on the back of the speaker passes through the acoustic resonance path, so that heavy bass resonating in the acoustic resonance path is radiated into the vehicle interior from the opening formed in the rear tray board. Therefore, it is possible to reinforce heavy bass which is often insufficient in the in-vehicle speaker, and reproduce well-balanced sound.

Further, in the case of the second in-vehicle rear tray speaker system, reproduced sounds from the front and rear surfaces of the speaker incorporated in the back cavity portion pass through the respective acoustic resonance paths, and have heavy basses which resonate with the respective acoustic resonance paths. The radiation is radiated from the respective openings of the rear tray board into the vehicle interior. Therefore, it is possible to efficiently enhance heavy bass which is often insufficient in the vehicle-mounted speaker.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIGS. 1 and 2 show an embodiment in which the in-vehicle rear tray speaker system of the present invention is applied to a two-box car. FIG. 1 is an external view of the rotary rear tray board in a closed state, and FIG. 2 is an external view of the rear tray board in an open state.

A rear tray board 3 for partitioning the cabin 1 and the trunk room 2 is pivotally supported by side boards (not shown) by support shafts 4 at both left and right ends thereof, and is mounted to be vertically rotatable. Further, although not shown, the rear tray board 3 has one end connected to a hatchback-type rear window 5 by a pulling wire or the like. When the rear window 5 is opened and closed, the rear tray board 3 interlocks with this as shown in FIG. As shown, it is opened upward so that luggage can be freely taken in and out of the trunk room 2 from the rear of the vehicle.

Two embedded speaker units 7a and 2b for L and R channels for stereo playback are attached to the rear tray board 3 at left and right positions on the rear side. A rectangular opening 8 serving as a radiation port is formed. On the back surface of the rear tray board 3, a flat and thin back cavity portion 6 composed of a closed space having a predetermined volume is integrally fixed so as to cover the entire rear tray board back surface. .

3 to 5 show the detailed structure of the rear tray board 3 and the back cavity 6 part. The back cavity portion 6 is fitted into a fitting wall 9 on the rear surface of the rear tray board 3, and is integrally fixed by bonding means such as bonding. The back cavity section 6 constitutes the back cavity of the rear surface of the speaker in the bass reflex type speaker.

The back cavity 6 is largely divided into two closed spaces on the left and right sides by a central partition plate 10. And
The inside of the sealed space on the left side corresponding to the R channel speaker unit 7a is divided into two parts by two partition plates 11a and 12a in a folded shape, and the back surface of the speaker unit 7a and the opening 8 are separated.
A predetermined length acoustic resonance path 13a is formed between the acoustic resonance paths 13a. The right enclosed space corresponding to the L-channel speaker unit 7b is divided into two folds by two partition plates 11b and 12b, and a predetermined length of sound is connected between the back surface of the speaker unit 7b and the opening 8. A resonance path 13b is formed.
The two acoustic resonance paths 13a and 13b are designed such that they resonate to a desired heavy bass (for example, 30 Hz), and are inverted in phase from the opening 8 and radiated into the vehicle interior.

The vehicle-mounted rear tray speaker system of the present invention having the above-described configuration is normally used in the state shown in FIG. That is, the reproduced sound from the front of the two speaker units 7a and 7b is directly radiated directly into the vehicle interior. On the other hand, the bass sounds on the back of the loudspeaker obtained by the resonance of the acoustic resonance paths 13a and 13b are respectively radiated from the opening 8 into the vehicle interior.

Accordingly, the bass reflex type speaker system is integrally formed on the rear tray board portion, and the sound can be reproduced in a well-balanced manner from high to low bass.

In the case of the present invention, acoustic resonance paths 13a and 13b having relatively long path lengths are formed in the back cavity portion 6. For this reason, the speaker unit 7 is not affected by the air load in the acoustic resonance paths 13a and 13b.
The efficiency of a and 7b is slightly reduced. Therefore, in actual use, it is desirable to drive the speaker units 7a and 7b with a dedicated amplifier in a booth in order to compensate for the decrease in speaker efficiency due to the air load. FIG. 6 shows an example of frequency characteristics of the speaker system of the present invention when driven by a dedicated amplifier. For comparison, the conventional rear tray speaker system (Fig. 10) and the box volume 10
The frequency characteristics of the bass reflex type speaker alone are also shown. As is clear from the figure, in the case of the rear tray speaker system of the present invention, it is possible to reproduce a well-balanced sound whose low range extends to around 30 Hz.

In the above-described embodiment, one opening 8 is formed as a port for radiating bass sound, and extends over the left and right acoustic resonance paths. However, independent openings are provided for the left and right speaker units 7a and 7b, respectively. The bass may be radiated from the opening.

7 and 8 show a second embodiment of the rear tray speaker system for mounting on a vehicle according to the present invention.

The second embodiment is configured as a 3D woofer dedicated to heavy bass reproduction. A first opening 16 is formed in the lower right corner of the surface of the rear tray board 3, and a second opening 17 is formed in the upper left corner. And a woofer unit 18 for heavy bass reproduction is installed in the back cavity 6. Then, by dividing the front side of the woofer unit 18 by a partition plate 19, an acoustic resonance path 20 connecting the front surface of the woofer unit 18 and the opening 16 is formed.
The rear side of the woofer unit 18 is divided by three partitioning plates 21 to 23 into a folded shape, thereby forming an acoustic resonance path 24 connecting the rear side of the woofer unit 18 and the opening 17. Acoustic resonance path 1
7, 22 are designed to have a path length that resonates with a predetermined desired heavy bass.

In the case of the second embodiment, the deep bass obtained by the acoustic resonance paths 20, 24 is radiated from the respective openings 16, 17 toward the vehicle interior. Therefore, it is possible to regenerate while increasing the heavy / low temperature more efficiently.

In each of the first and second embodiments, the openings 8, 16, and 17 are square holes. However, the present invention is not limited to this, and other hole shapes such as round holes may be adopted. Of course.

〔The invention's effect〕

As is apparent from the above description, when the rear tray speaker system of the present invention is used, a bass-reflex speaker system is integrally formed on the rear tray board by forming a flat and thin back cavity portion on the rear surface of the rear tray board. Therefore, the volume of the speaker system, in particular, the thickness of the speaker system in the vertical direction can be reduced, and an excellent effect that a relatively small-diameter speaker can efficiently reproduce heavy bass sound while securing a trunk room space. To play.

In addition, since the back cavity portion is provided on the rear surface of the rear tray board, the rigidity of the rear tray board, which is often made of plastic or the like, can be increased, and the strength around the trunk room of the vehicle can be improved.

The in-vehicle rear tray speaker system of the present invention can be applied to both a two-box car and a three-box car as long as the rear tray board for partitioning the cabin and the trunk room is provided. The effect is more remarkable in a two-box car in which it is difficult to secure airtightness.

[Brief description of the drawings]

FIG. 1 is an external view of a trunk room portion of the first embodiment of the present invention with the rear tray board closed, FIG. 2 is an external view of a trunk room portion of the same embodiment with the rear tray board open, FIG. FIG. 4 is an exploded perspective view of a rear tray board portion of the embodiment, FIG. 4 is a rear view of the rear tray board, FIG. 5 is a plan view of a back cavity portion, FIG. 6 is a frequency characteristic diagram of the first embodiment, FIG. FIG. 8 is an exploded perspective view of a rear tray board portion in a second embodiment of the present invention, FIG. 8 is a plan view of a back cavity portion of the above embodiment, and FIGS. 9 to 12 each show a configuration example of a conventional rear tray speaker system. FIG. 1 ... car room, 2 ... trunk room, 3 ... rear tray board, 6 ... back cavity part, 7a, 7b ... speaker unit, 8, 16, 17 ... opening, 10-12,19,21- twenty three…
… Partition plate, 13,20,24 …… Acoustic resonance path, 18 …… Woofer unit.

Claims (2)

(57) [Claims] 1. A flat and thin back cavity portion comprising a closed space covering the rear tray board back surface is formed on the rear surface of the rear tray board, and two openings communicating with the back cavity portion are formed at appropriate positions on the front surface of the rear tray board. While drilling,
A speaker is buried and installed in one of the openings toward the vehicle interior, and the inside of the back cavity portion is partitioned by a partition wall between the rear tray board back surface and a surface facing the rear tray board back surface, thereby forming the other of the openings. A rear-panel speaker system for vehicle mounting, wherein an acoustic resonance path of a predetermined length is formed between the speaker and the back of the speaker. 2. A flat and thin back cavity portion comprising a closed space covering the rear tray board back surface is formed on the rear surface of the rear tray board, and a speaker is built in the back cavity portion in a direction perpendicular to the rear tray board. With
At the appropriate position on the front surface of the rear tray board, two independent openings communicating with the back cavity portion are formed, and inside the back cavity portion, between the rear tray board back surface and the surface facing the rear tray board back surface by a partition wall. An acoustic resonance path connecting one of the openings to the front of the speaker and the other of the openings to the back of the speaker by partitioning the rear tray speaker system for a vehicle.