JPS6325760B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fader balance device for an in-vehicle audio system, and in particular, it automatically adjusts the volume ratio output from a plurality of distributed speakers according to the distribution of the number of people seated. This is what you are trying to set.

If the car audio system is a 2-speaker type, the volume ratio output from the left and right speakers can be adjusted using a sliding or rotary volume control, and if it is a 4-speaker type, the volume ratio output from the front, rear, left, and right speakers can be adjusted. Volume can be adjusted using a universal joint lever. FIG. 1 is a schematic diagram of a conventional in-vehicle audio system, taking a four-speaker type as an example. The sound source is radio tuner 1 or cassette deck 2, and their left signal L and right signal R
is selected by the changeover switch 3. 4 is a volume controller, 5 is a manually set fader balance circuit that can change the volume ratio of front, rear, left, and right sides with the joystick, 6 is a power amplifier that amplifies the audio signal reaching each speaker, FL is the left front speaker, and FR is Right front speaker, RL is left rear speaker, and RR is right rear speaker. Further, FIG. 2 shows the speaker arrangement and the positional relationship of the seats, where A is the driver's seat, B is the passenger seat, C is the rear left seat (behind the passenger seat), and D is the rear right seat (behind the driver's seat).

However, manually setting the volume balance while the vehicle is running is dangerous, and since the operating section is usually located near the driver's seat, it is difficult to operate from the rear seat. Furthermore, since the optimal volume balance changes depending on the distribution of people in the vehicle, it is extremely troublesome to manually set it each time the number of passengers or the riding position differs. Moreover, since the volume balance generally tends to be best determined by the person who adjusts it (does not rely on majority rule), it may not be desirable depending on the seating position.

The present invention attempts to solve the above-mentioned problems at once by detecting the distribution of people actually seated and automatically determining the volume balance. The present invention relates to a fader balance device for an in-vehicle audio system in which a plurality of speakers are distributed in the interior of an automobile. The present invention includes a data conversion section that outputs a preset fader balance control signal as an input, and an attenuation control section that selectively attenuates an audio signal reaching each speaker in accordance with the fader balance control signal. This feature will be described in detail below with reference to the illustrated embodiment.

FIG. 3 is a configuration diagram of a fader balance circuit 5 showing an embodiment of the present invention, in which 7A to 7D are seating sensors (a type of pressure sensitive switch) provided in seats A to D, respectively, and 8 is a seating sensor 7A. ~ Parallel 4-bit seating sensor signal SA ~ SD from 7D (0 at seating,
9 is a data conversion unit using a read-only memory (ROM) that is accessed using the address 1) when the seat is vacant; 9 is a 4-bit fader balance control signal OFL, CFR, CRL, which is output from the conversion unit 8;
This is an attenuation control section that selectively attenuates the audio signals L and R given to the speakers FL, FR, RL, and RR by the CRR (though directly to the power amplifier 6).
When the control signal CFL is 1, the attenuation control section 9 turns on the transistor TR to attenuate the audio signal L to the speaker FL, but when CFL is 0, the signal L is passed through with the transistor TR turned off. . The same goes for the other control signals CFR, CRL, and CRR, and binary logic control is performed in which if they are 1, they are attenuated, and if they are 0, they are not attenuated.

Figure 4 is an explanatory diagram of ROM8, and shows the seating sensor signal.
Fader balance control signals CFL to CRR are read using SA to SD as addresses. Control signal CFL
~CRR of 1 and 0 are set in advance by considering the acoustic effect (preferably by experiment), and in this example,
16 patterns are stored. No. in Figure 5.
1 to No. 16 are explanatory diagrams of volume balance according to these 16 patterns. No. 1 is a state in which all seats A to D are seated. In this case SA=SB=SC
=SD=0, so from ROM8 CFL=0,
CFR=CRL=CRR=1 is read and the speaker
Audio signals to FL, RL, and RR are attenuated.
No. 2 is seated in seats A to C, and seat D is vacant. In this case, SA=SB=SC=0, SD=1
From ROM8, CFL=CFR=CRR=0, CRL=
1 is read and only the audio signal to speaker RL is attenuated. The same applies below, for example No. 4
In No. 16, where no one is riding, the audio signals for all speakers are attenuated. Incidentally, the data conversion section 8 can also be realized by software of a microcomputer. 6th
The flowchart is shown in the figure.

As described above, according to the present invention, the fader balance of a car audio system having a plurality of speakers is automatically set optimally according to the distribution of people on board, so This has the advantage that there is no need for the driver to make manual settings each time there is a risk, depending on the change.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an example of an in-vehicle audio system, FIG. 2 is an explanatory diagram showing the arrangement of speakers, and FIG. 3 is a configuration diagram showing an embodiment of the present invention.
Figure 4 is an explanatory diagram of the data conversion section using ROM.
FIG. 5 is an explanatory diagram of the volume balance according to various seating situations, and FIG. 6 is a flowchart when configuring the data conversion section using software. In the figure, FL, RL, FR, and RR are speakers, 5 is a fader balance circuit, 7A to 7D are seating sensors, 8 is a data conversion section, and 9 is an attenuation control section.

Claims (1)

[Claims] 1. In a fader balance device for an in-vehicle audio system in which a plurality of speakers are distributed in a vehicle interior, a seating sensor provided for each seat and a seating sensor signal obtained from the seating sensor are input in advance. The present invention is characterized by comprising a data conversion section that outputs a set fader balance control signal, and an attenuation control section that selectively attenuates audio signals reaching each speaker in accordance with the fader balance control signal. , fader balance device for automotive audio systems.