JPS63125095A - On-vehicle speaker - Google Patents

Abstract

PURPOSE:To completely reproduce a low pitched sound zone by constituting two parallel acoustic tubes of different length in the construction body of a car, providing a driver unit in the inlet of the acoustic tube and disposing the aperture of the acoustic tube in a rear parcel. CONSTITUTION:The musical signals of right and left channels are inputted to the driver units 17, 18 attached to front doors 9, 10. On the rear surface of the driver units 17, 18, the acoustic tubes 19, 20 of the different length previously integrally formed on the side surface of frames 15, 16 and a back seat 6 from the front doors 9, 10 are disposed, the apertures 21, 22 are disposed in the rear parcel 5, and the sound on the units 17, 18 is propagated in the acoustic tubes 19, 20 and radiated in the room of the car. When the length of the acoustic tubes 19, 20 is 1/2 as long as the wavelength of a low threshold frequency, the acoustic tubes 19, 20 resonates with this frequency. The length of the acoustic tubes 19, 20 is set so as to compensate the mutual peak dip of a sound pressure frequency characteristic according to both resonance conditions.

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, and conventional technology for expanding bass frequencies includes vehicle-mounted speakers that have 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. 7 shows how a conventional vehicle-mounted speaker is installed. In Figure 7, 1 is the car door, 2 is the door 1
3 is a bass reflex type speaker cabinet attached to cabinet 2, 4 is a speaker unit attached to cabinet 2,
is a bass reflex port provided in the cabinet 2, and its opening is the same as that of the speaker unit 3.It is mounted 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. Cabinet 2 is a bass reflex type, and its bass reflex port 4
The opening is the same as the surface on which the speaker unit 3 is attached, 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 becomes high, and the reproduction of bass frequencies is not satisfactory.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention provides an in-vehicle speaker capable of sufficiently reproducing bass frequencies in response to the recent significant improvement in the quality of music signals.

Means for Solving the Problems To achieve this objective, the in-vehicle speaker of the present invention has the following features:
Two sound tubes of different lengths are arranged in parallel in the car structure that makes up the vehicle body, and a driver unit is provided at the entrance of the sound tube, and an opening of the sound tube is arranged in the rear parcel.

Effect of the present invention With this configuration, two parallel acoustic tubes of different lengths are formed in advance in a part of the car body, the acoustically necessary length and cross-sectional area are secured, and a driver unit is provided at the entrance of the acoustic tube, and the opening Since it is placed in the rear parcel, it is possible to significantly increase the acoustic output in the low frequency range due to the resonance of the sound tube.

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

FIG. 1 shows the structure of a vehicle-mounted speaker according to an embodiment of the present invention. In Figure 1, 6 is the rear parcel, 6 is the rear seat, 7.8 is the rear door, 9, 1Q is the front door, 11.12 is the front / -to, 13.14 is the curl side, 16.16 17 and 18 are the frame, 17 and 18U driver units, 19 and 20 are the front doors 9 and 10, the sides of the frames 16 and 16, sound tubes of different lengths that are integrally formed in advance on the rear seat 6, and 21 and 22 are the rear Opening of acoustic tube 19.20 provided in parcel 5, 23
．． 24 [This is a mid-high frequency speaker mounted on the front door 9, 1o.

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 driver units 17 and 18 attached to the front doors 9 and 1 degrees. Driver unit 1
7. On the back of 18, from the front doors 9, 10 to the frame 15
．． A sound tube 19° 20 integrally molded in advance is arranged on the side of the driver unit 16 and the rear trunk 6, and its openings 21 and 22 are provided in the rear parcel 5, so that the driver unit 17
．． The sound from the rear side of the driver unit 18 is propagated through the acoustic tubes 19 and 20, and is radiated into the vehicle interior through the opening 21 and 22 along with the sound from the front side of the driver unit 17 and 18. Although the phase of the sound at the front and back of the driver unit 17 and 18 is reversed,
The length of the acoustic tube 19.20 is 1/ of the wavelength of the low limit frequency.
2, the acoustic tubes 19, 20 will resonate at this frequency, and the sounds from the front and rear sides of the driver units (17, 18) will be in phase and will be added together inside the vehicle.

Further, mid-high tones are reproduced by mid-to-high tones speakers 23 and 24 mounted on the front doors 9 and 10.

As described above, according to this embodiment, the driver unit 7) 17
, 18 are arranged with acoustic tubes 19 and 20 of different lengths, and by utilizing the resonance of the acoustic tubes 19 and 20 and the phase inversion effect due to their lengths, they mutually compensate for the low sound pressure level parts and output sound. The aim is to significantly increase the number of employees.

FIG. 4 compares the sound pressure spectrum characteristics in the vehicle interior between this embodiment and the conventional one. The sound source is pink noise, which has a frequency of 1/3 in the band from 20 Hz to 20 KHz.
This is the result of spectrum analysis performed for each octave. In the example in which the results shown in FIG. 2 were obtained, the driver fi14I
ff diameter dynamic speaker, acoustic tube diameter 1oα
It was a straight pipe with a total length of 3 m. The conventional example is a bass reflex type with a cabinet volume of 2 liters, and the speaker unit is 12ff in diameter and mounted on both front doors. From the results shown in the figure, a significant improvement in the sound pressure level of 15 dB or more is achieved in the low frequency range of 100 Hz or less. In addition, two acoustic tubes 19,20'i of different lengths are placed in parallel on the back of the two driver units 17,18, and the acoustic tubes reproduce low-frequency components that can be considered omnidirectional as a sound source. High-pitched sounds are reproduced by medium and high-pitched sound speakers 23 and 24 mounted on the front doors 9 and 10 to create a sense of spaciousness in the sound image.

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

FIG. 2 shows a structural diagram of a vehicle-mounted speaker according to a second embodiment of the present invention. In FIG. 2, the same components as those in the first embodiment are given the same numbers. In Fig. 2, 25.26 is a driver unit, 27.28 is an acoustic tube formed by integral molding from the rear door 7.8 to the side of the frame 15.16, and the rear bar cell 5, 29, 30.
is the opening of the acoustic tube 27, 28 provided in the rear bar cell 6.The operation of the structure of the vehicle-mounted speaker constructed as described above will be described below.

Of the left and right channel music signals (L+R), electrically divided low frequency components are input to a driver unit 25.26 attached to the rear door 7.8. At the back of the driver unit 25.26, from the rear door 7.8 to the frame 1
Acoustic tubes 27 and 28, which are integrally molded in advance, are arranged on the sides of the driver unit 25 and 16, on the rear parcel side, and the openings 29 and 30 of the acoustic tubes are provided in the rear parcel 5, so that the sound from the back of the driver unit 25 and 26 is The sound propagates through the tubes 27 and 28 and is radiated into the vehicle interior through the openings 29 and 30 along with the sound from the front of the driver unit 25 and 26. The phases of the sounds on the front and rear sides of the driver unit (driver unit) 25 and 26 are reversed, but if the length of the acoustic tubes 27 and 28 is set to be 1/2 of the wavelength of the low limit frequency, the acoustic tube 27.28
resonates at this frequency, and the driver unit 25.2
The sounds from the front and rear of the 6 are in phase and added together inside the vehicle. Mid-high tones are reproduced by mid-to-high tones speakers 23 and 24 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. 3 shows a structural diagram of a vehicle-mounted speaker according to a third embodiment of the present invention. In FIG. 3, the same components as in the first embodiment are given the same numbers. In Figure 3, 31.32 is the driver unit, 33.34 is the side of the frame 15.16 from the curl side 13.14,
An acoustic tube formed integrally with the rear bar cell 6 in advance,
36°36 is the sound tube 33.34 installed in the rear bar cell 5
It is the opening of

The operation of the vehicle-mounted speaker configured as described above will be described below. Music signals (L+R) of both left and right channels (input to the driver unit 31.32 attached to the q curl side 13゜14. On the back of the driver unino 1-31.32, the curl side 13.1
From 4, frame 15.16 retro 1st page, rear bar cell 6
Since acoustic tubes 33, 34, which are integrally molded in advance in
3.34 is propagated to the driver units 3j, 32
The sound is radiated into the vehicle interior through the openings 35° and 36 along with the sound from the front of the vehicle. The phases of the sound on the front and rear sides of the driver units 31 and 32 are reversed, but if the length of the acoustic tubes 33 and 34 is set to be 1/2 of the wavelength of the low limit frequency, at this frequency It resonates, and the sounds from the front and back of the driver unit 7) 31 and 32 become in phase and are added together inside the vehicle. Further, mid-high tones are reproduced by mid-to-high tones speakers 23 and 24 mounted on the front doors 9 and 1Q.

As mentioned above, the second. According to the third embodiment, an acoustic tube 27.2 is provided on the back side of the driver unit 25, 26, 31.32.
8, 33, and 34, and by utilizing this resonance and the phase inversion effect due to its length, the acoustic output is significantly increased, and its operation is almost the same as the first embodiment. Just an acoustic tube 2γ.

Since the total length of the acoustic tube 27.2B is shortened, the low limit frequency increases and it becomes somewhat difficult to expand the low frequency range compared to the first embodiment.

33.34i It is not necessary to extend to the front doors 9, 1o, and the structure of the vehicle body is simplified.

Although the cross-sectional shape of the acoustic tube is not described in the above embodiment, as shown in FIG. 6, (A) circular, (B)
It may be square, (C) polygonal, or (D) irregular, and may have any shape as long as its cross-sectional area is equal to the cross-sectional area required for the acoustic tube.

In addition, in the above embodiment, the acoustic tube was a straight tube with a constant cross-sectional area over the entire length, but if it were to be shaped like a horn, with the cross-sectional area increasing as it approaches the opening of the acoustic tube, the sound tube would propagate through the tube. Impedance matching between the sound and the interior space of the vehicle is improved, and disturbances in sound pressure characteristics are reduced. FIG. 6 shows the structure of the door when it is opened and closed. FIG. 6 shows the door when it is open, and FIG. 6B shows the door when it is closed. The structure is fixed to prevent sound leakage.

Effects of the Invention The present invention configures two parallel acoustic tubes of different lengths when molding a door or frame, which is a structure of a car, and
By providing a driver unit on one side and arranging the opening in the rear parcel, it is possible to achieve a significant increase in acoustic output in the low frequency range due to the resonance of the acoustic tube. In addition, by creating a horn shape in which the cross-sectional area of the acoustic tube increases toward the opening, it is possible to fully increase the acoustic output due to the horn effect. Because the cross-sectional area is secured, the bass limit is not limited by the cabinet volume as in the past, and the car speaker is capable of reproducing sufficient bass to accommodate the significant improvement in the quality of recent music signals. It is possible to realize this.

[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 structural diagram of a vehicle-mounted speaker according to a second embodiment of the present invention, and FIG. 3 is a structural diagram of a vehicle-mounted speaker according to a second embodiment of the present invention. FIG. 4 is a diagram of the sound pressure spectrum characteristics of the present invention and a conventional vehicle-mounted speaker in the vehicle interior, FIG. 6 is a cross-sectional view of the acoustic tube of the present invention, and FIG. FIG. 7 is a structural diagram of a conventional vehicle-mounted speaker, showing the structure of the acoustic tube when the door is opened and closed. 6...Rear bar cell, 6...Rear trunk, 7゜8...Rear door, 9,10...
・Front door, 11° 12...Front door, 13
．． 14... Carl side, 15.16...
・Frame, 17, 18, 26° 26. 31, 32・
...Driver unit, 19°20.27.2B
, 33.34...Acoustic tube, 21°22.29,
30,36.36...opening of acoustic tube, 23,
24...Speaker for medium and high frequencies, 3Q...marked, closed cell polymer material. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 6
Picture Prisoner Kaishu (β) Kairaigin 2q-Acoustic Tube 30-&Bubble Polymer Material

Claims (8)

[Claims] (1) Parallel acoustic tubes of different lengths are configured using the structure of a car, a driver unit is provided at the entrance of the acoustic tube, and an opening of the acoustic tube is provided in the rear parcel. In-vehicle speakers. (2) The vehicle-mounted speaker according to claim 1, wherein the length of each acoustic tube is set so that both resonance conditions compensate for each other's peaks and dips in sound pressure frequency characteristics. (3) The vehicle-mounted speaker according to claim 1, wherein the driver unit is provided in a front door. (4) The vehicle-mounted speaker according to claim 1, wherein the driver unit is provided in a rear door. (5) The vehicle-mounted speaker according to claim 1, wherein the driver unit is provided on the curl side. (6) The vehicle-mounted speaker according to claim 1, wherein the cross-sectional area of the acoustic tube increases as it approaches the opening. (7) The vehicle-mounted speaker according to claim 1, wherein the sound tube has a constant cross-sectional area. (8) Claims characterized in that the sound tube provided in the door has a structure in which a closed-cell polymeric material is fixed around the cut surface to prevent sound leakage when the door is opened and closed. The in-vehicle speaker according to item 1.