JPS63120583A - On-vehicle speaker - Google Patents

Abstract

PURPOSE:To considerably increase an acoustic output by means of resonance of an acoustic tube in a low sound frequency domain by preliminarily forming the acoustic tube with a part of the body of the vehicle, providing a driver unit at the entrance of tube, and disposing its opening at the front door part of the body. CONSTITUTION:In the rear of the driver unit 16, the acoustic tube 17 is disposed integrally with the vehicle-body extending from a trunk room 30, along the side surface of a frame 15, to a rear seat 6, and the opening 18 of the tube 17 is provided at the place of the front door 9. The length of the acoustic tube 17 is made half the wave length of a wave in lower limit frequency, so that the tube 17 resonates at this frequency. Intermediate and higher sounds are reproduced by speaker units 19, 20 for intermediate/higher sounds mounted on the front doors 9, 10. As a result, the drastic enhancement of acoustic output is made able by making use of the resonance of the acoustic tube 17 in low sound frequency domain.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a vehicle-mounted speaker installed in a vehicle interior.

Conventional technology In recent years, in-vehicle compact disc players and high-output power amplifiers have been commercialized, and the quality of music signals in the car interior has improved significantly, and there is a strong demand for improved performance of the in-vehicle speakers that play these signals. There is something strong. Under these circumstances, a major issue in reproducing sound inside a vehicle is the reproduction of bass frequencies.As a conventional technology for expanding bass frequencies, there is a vehicle-mounted speaker that has a dedicated bass reflex type cabinet placed in the door.

Hereinafter, the above-mentioned conventional vehicle-mounted speaker will be explained with reference to the drawings.

FIG. 6 shows the mounting state of a conventional vehicle-mounted speaker. In Fig. 6, 1 is a car door, 2 is a bass reflex type speaker cabinet attached to the door 1, 3 is a speaker unit attached to the cabinet 2, and 4 is a bass reflex type speaker cabinet attached to the cabinet 2. The opening of the port is the same as that of the speaker unit 3, and its mounting is on the same surface.

The operation of the vehicle-mounted speaker configured as described above will be described below.

The music signal amplified by the amplifier is input to a speaker unit 3 attached to a cabinet 2. The cabinet 2 is of a bass reflex type, and the opening of the bass reflex port 4 is the same as the mounting surface of the speaker unit 3, and the bass range is expanded by the acoustic resonance of the bass reflex port 4.

Problems to be Solved by the Invention However, with the above configuration, the volume that can be taken up as a cabinet is limited, the resonance frequency of the bass reflex port 4 is too high, and the reproduction of bass frequencies is not satisfactory.

The present invention has been made in view of the above-mentioned problems, and provides an in-vehicle speaker capable of sufficiently reproducing low frequency ranges in response to the recent significant improvement in the quality of music signals.

Means for Solving the Problems In order to achieve this object, the in-vehicle speaker of the present invention has the following features:
The vehicle structure that constitutes the vehicle body constitutes at least one acoustic tube, and a driver unit is provided at the entrance of the acoustic tube,
The acoustic tube opening is located in the front door.

Function: With this configuration, a part of the car body forms an acoustic tube in advance,
If the length and cross-sectional area necessary for acoustics are secured, a driver unit is installed at the entrance, and the opening is located at the front door, it is possible to significantly increase the acoustic output in the low frequency range through acoustic tube resonance. .

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 shows a structural diagram of a vehicle-mounted speaker according to an embodiment of the present invention. In Figure 1, 5 is the rear parcel, 6 is the rear seat, 7 and 8 are the rear doors, 9 and 10 are the front doors, 11.12 is the front 5 par seat, 13.14 is the curl side, and 15 is a frame,
16 is the driver unit, 3o is the trunk room, 17
18 is the opening of the acoustic tube 17, and 19° and 20 are speakers for medium and high frequencies mounted on the front doors 9 and 1o. Unit, 31 is acoustic tube 1
This is the joint between the frame 15 of No. 7 and the front door 9.

The operation of the vehicle-mounted speaker configured as described above will be described below. The left and right channel music signals (L+R) are input to a driver 16 installed at 3° in the trunk room. At the rear of the driver unit 16, an acoustic tube 17 is arranged which is integrally molded in advance from the trunk room 3o to the side of the frame 15 and the rear seat 6, and its opening 18 is provided in the front door 9. The sound from the rear surface propagates through the sound tube 17 and is radiated into the vehicle interior through the opening 18. If the length of the acoustic tube 17 is set to be the wavelength A of the low limit frequency, the acoustic tube 17 will resonate at this frequency.

6 Per/ Also, mid-high tones are reproduced by subica units for mid-to-high tones mounted on the front doors 9 and 10.

As described above, according to this embodiment, the driver unit 16
An acoustic tube 17 is arranged on the back side of the acoustic tube 17, and resonance of the acoustic tube 17 is utilized to significantly increase the acoustic output. FIG. 2 is a comparative display of the sound pressure spectrum characteristics in the vehicle interior between this embodiment and the conventional one. The sound source is pink noise, and the result is a spectrum analysis performed for each octave in the band from 20t (z to 20 KHz).In the example that obtained the results shown in Figure 2, the driver unit is a dynamic The speaker and acoustic tube were straight tubes with a diameter of 101 m and a total length of 3 m.

The conventional example is a bass reflex type with a cabinet volume of 2 liters, a speaker unit with a diameter of 12α, and mounted on the front door. The results shown in the figure show that the sound pressure level has been significantly improved by 15 dB or more in the low frequency range of 100 Hz or less.

Next, regarding the second embodiment of the present invention, turn to drawing 7.
7 Explain with reference.

FIG. 3 shows the structure of a vehicle-mounted speaker according to a second embodiment of the present invention. In FIG. 3, the same components as those in the first embodiment shown in FIG. 1 are given the same numbers.

In FIG. 3, 21 is a driver unit provided on the rear door 7, 22 is an acoustic tube formed integrally from the rear door 7 to the side surface of the frame 15, and from the front door 9 by integral molding.
3 is an opening of the acoustic tube 22 provided in the front door 9, and 32 is a joint between the frame 15 of the acoustic tube 22 and the rear door 7.

The operation of the structure of the vehicle-mounted speaker configured as described above will be described below.

The electrically divided low-frequency components of the left and right channel music signals (L and R) are input to a driver 21 attached to the rear door 7. There is a rear door 7 on the back of the driver 21.
An acoustic tube 22 is disposed integrally with the side surface of the frame 15 and the front door 9, and its opening 23 is connected to the front door 9.
The sound from the rear side of the driver 21 propagates through the acoustic tube 22 and is radiated into the vehicle interior through the opening 23 along with the sound from the front side of the driver 21. Although the phases of the sound from the front and rear sides of the driver 21 are reversed, if the length of the acoustic tube 22 is set to be the wavelength of the low-frequency limit frequency, the acoustic tube 22 will resonate at this frequency, Also, the sounds from the front and back of the driver 21 are in phase and are added together inside the passenger compartment. Mid-high tones are reproduced by a subica unit (19.20) for mid-to-high tones mounted on the front doors 9 and 1o.

A third embodiment of the present invention will be described below with reference to the drawings.

FIG. 4 shows the structure of a vehicle-mounted speaker according to a third embodiment of the present invention. In FIG. 4, the same components as those in the first embodiment shown in FIG. 1 are given the same numbers.

In FIG. 4, reference numeral 24 denotes a driver unit, 25id an acoustic tube formed from the rear parcel 5, the side of the frame 15, and the front door 9 by integral molding in advance, and 26 the acoustic tube 25 provided on the front door 9. It is an opening.

The operation of the in-vehicle speaker configured as described above will be explained below. The left and right channel music signals (L + R) are input to the driver unit 24 attached to the rear parcel 5.

On the back side of the driver unit 24, an acoustic tube 25 is arranged which is integrally molded in advance from the rear parcel 5 to the side surface of the frame 15 and the front door 9, and its opening 26 is provided in the front door 9. The sound from the rear side of the driver unit 24 propagates through the acoustic tube 25 and is radiated into the vehicle interior through the opening 26 along with the sound from the front side of the driver unit 24.

The phases of the sound from the front and rear sides of the driver unit 24 are reversed, but if the length of the sound tube 25 is set to be the wavelength A of the low limit frequency, it will resonate at this frequency, and the driver unit The sounds from the front and rear of the 24 are in the same phase and are added together inside the vehicle. Also, the middle and high tones are from the front door 9.
, mounted on 10 (speaker unit for medium and high frequencies) 19
．． It will be played at 20.

As mentioned above, the second. According to the third embodiment, an acoustic tube 22゜10 page 25 is arranged on the back of the driver unit 21, 24, and the acoustic output is adjusted by utilizing this resonance and the phase inversion effect due to its length. The operation is almost the same as that of the first embodiment. However, in the second embodiment, the total length of the acoustic tube 22 is shorter than that of the first embodiment, so the low limit frequency increases and it is somewhat difficult to expand the bass range compared to the first embodiment. However, the acoustic tube 22 is connected to the rear parcel 5. There is no need to extend the trunk room 3Q, and the structure of the vehicle body is simplified.

Although the cross-sectional shapes of the acoustic tubes are not described in each of the above embodiments, as shown in FIG.
) Square shape, (0) polygonal shape, (d) irregular shape, and any shape can be used as long as the cross-sectional area is equal to the cross-sectional area necessary for the acoustic tube.

In addition, in each of the above embodiments, the acoustic tube was a straight tube with a constant cross-sectional area over the entire length, but if it were made into a horn shape whose cross-sectional area increases as it approaches the opening of the acoustic tube, the sound tube would propagate through the acoustic tube. The impedance matching between the sound produced by the vehicle and the interior space of the vehicle is improved, and disturbances in the sound pressure characteristics are reduced.

Effects of the Invention The present invention provides a system in which one or more acoustic tubes are formed when a door or frame, which is a structural body of a car, is formed, a driver unit is provided at the entrance thereof, and an opening is placed in the front door. , it is possible to achieve a significant increase in acoustic output in the low frequency range due to acoustic tube resonance. In addition, by making the acoustic tube into a horn shape in which the cross-sectional area increases toward the opening, it is possible to increase the acoustic output due to the horn effect. Because the length and cross-sectional area are secured, the bass limit is not limited by the cabinet volume as in the past, and the in-vehicle device is capable of fully reproducing bass frequencies that correspond to the significant improvement in the quality of recent music signals. This makes it possible to realize a speaker for use in other applications.

[Brief explanation of the drawing]

FIG. 1 is a structural diagram of a vehicle-mounted speaker according to an embodiment of the present invention, FIG. 2 is a sound pressure spectrum characteristic diagram in a vehicle interior of a vehicle-mounted speaker of the present invention and a conventional vehicle-mounted speaker, and FIG. 3 is a structural diagram of a vehicle-mounted speaker according to an embodiment of the present invention. FIG. 4 is a structural diagram of a vehicle-mounted speaker according to a third embodiment of the present invention, FIG. 5 is a cross-sectional view showing various cross sections of the acoustic tube of the present invention, and FIG. is a structural diagram of a conventional vehicle-mounted speaker. 5... Rear parcel, 6... Rear seat,
7゜8...Rear door, 9,10...Front door, 11゜12...Front seat, 13,14...
... Curl side, 15 ... Frame, 16,
21. 24...Driver unit, 17,2
2.25...Acoustic tube, 18.23.25-...
...Acoustic tube opening, 19,20...Speaker unit for medium and high frequencies, 31...Connection between acoustic tube frame and front door, 32...Acoustic tube The joint between the frame and the rear door. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 5
Figure (CJJ (1)) (G) (d'

Claims (6)

[Claims] (1) An in-vehicle speaker characterized in that at least one acoustic tube is configured in the structure of the vehicle, a driver unit is provided at the entrance of the acoustic tube, and an opening of the acoustic tube is located in a front door. (2) The vehicle-mounted speaker according to claim 1, wherein the driver unit is provided in a trunk room using one acoustic tube. (3) The vehicle-mounted speaker according to claim 1, wherein the driver unit is provided in a rear door using one sound tube. (4) The vehicle-mounted speaker according to claim 1, wherein the driver unit is provided in the rear parcel using one acoustic tube. (5) The vehicle-mounted speaker according to claim 1, wherein the cross-sectional area of the acoustic tube increases as it approaches the opening. (6) The vehicle-mounted speaker according to claim 1, wherein the sound tube has a constant cross-sectional area.