JPS59225700A - Device for controlling sound field - Google Patents

Abstract

PURPOSE:To attain the sound field control of an on-vehicle audio equipment automatically without malfunction in response to the seating position of a passenger by detecting the presence of the passenger at each seat position by an output signal of an infrared ray sensor and applying the sound field control based on the result. CONSTITUTION:The infrared rays 5-8 are fitted respectively just above each seat. The amount of infrared rays made incident to the infrared ray sensors is changed by the movement of the seated passenger and its output signal is as shown in A and C. Further, no passenger is seated, the output signal is nearly zero as shown in B and D. The output signal of the infrared ray sensors 5-8 is applied respectively to peak hold circuits 17-20 via amplifiers 9-12 and band pass filters 13-16 having a band of 0.1-10Hz. A processing device 28 calculates an address of a memory 27 to be accessed based on output signals i-l of comparators 21-24 applied via a data input section 25, reads the storage content stored in the address calculated by the memory 27 and optimum sound field control is attained via data output section 26 based thereupon.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a sound field control device for an in-vehicle audio system that can automatically control the sound field in accordance with the seating positions of all occupants.

Prior Art and Problems In order to provide optimal sound effects to the occupants in car audio systems, it is necessary to control the sound field (for example, adjust the volume output from each speaker, It is necessary to adjust the amount of crosstalk between each speaker, adjust the delay time between each speaker, etc.), but conventionally, sound field control was performed by manually operating variable resistors, etc. There were 6 drawbacks that the operation was complicated. In addition, in order to improve these drawbacks, each seat is equipped with a pressure sensor that detects the pressure when a person is seated, and the sound field control is automatically controlled based on the detection results of each sensor. Although such a device has been proposed, since it uses a pressure sensor to detect whether the passenger is seated or not, it has the disadvantage that it may malfunction if luggage or the like is placed on the seat.

Purpose of the Invention The present invention has improved the above-mentioned drawbacks, and its purpose is to automatically control the sound field of an in-vehicle audio system according to the seating position of the passenger without making any mistakes. Totoruru.

Structure of the Invention As shown in FIG. 1, the present invention detects the presence or absence of an occupant by a detection means based on the output signal of an infrared sensor S provided directly above the seating position of the occupant. Based on the detection results, sound field control is performed if the controller ≧T. still,
In the figure, O is the main body of the audio device, and SP is the speaker.

Embodiment of the Invention Figure 2 is a block diagram of an embodiment of the invention.
4 is an infrared transmission filter, 5 to 8 are pyroelectric infrared sensors that output a signal corresponding to the amount of change in incident infrared light, 9 to 12 are amplifiers, and 13 to 16 have a band of 0.1 to 10.
H3 is a fake band pass filter, 17 to 20 are peak hold circuits that hold the peak value for a certain period of time (for example, about 4 seconds), and 21 to 24 are peak hold circuits 17 to 2, respectively.
A comparator that compares the output signal of 0 with the threshold value and sets the output signal to "1" while the threshold value is smaller, 25 is a data input section, 26 is a data output section, 27 is a memory, and 28 is a A processing device consisting of a microprocessor etc., 29 the main body of the audio device, 50 a polarity inversion circuit, 61 an attenuator, 32 a delay circuit consisting of a bucket pre-gate device (BED) etc., 36 an attenuator, 34.35 an amplifier , 36-69 are speakers.

The infrared transmission filters 1 to 4 are respectively attached to the front of the light receiving portion of the infrared sensors 5 to 8.The infrared sensors 5 to 8 are respectively attached to the front right seat 40, as shown in FIG. It is installed directly above the front left seat 41, the rear right seat 42, and the rear left seat 43. Further, speakers 56 and 37 are attached to the right and left sides of the front door, respectively, and speakers 58 and 59 are attached to the right and left sides of the shelf board of the bulkhead.

Now, for example, front right seat 40. Assuming that an occupant is seated in the rear right seat 42, the amount of infrared rays incident on the infrared sensors 5 and 7 changes depending on the movement of the occupant seated in the seats 40 and 42, so the output signals α and 0 are respectively The results are shown in FIGS. 4(A) and 4(C).

Infrared rays from seats 41.43 also enter infrared sensors 6.8, but infrared sensors 5 to 8 and seats 4 to 4
3 is attached to the vehicle body while maintaining a certain positional relationship, so even if the vehicle body vibrates, the amount of infrared rays that enters the infrared sensor 6.8 remains almost constant; Faith that corresponds to the amount of change in infrared rays! The output numbers d and d of the infrared sensors 6 and 8 that output
As shown in B) and (D), it becomes almost zero.

The output signals a to d of the infrared sensors 5 to 8 are then sent to the peak hold circuit 1 via amplifiers 9 to 12 and band pass filters 13 to 16 having a band of 0.1 to 10 Hz, respectively.
Added to 7-20. Here, the bandpass filter 13
The reason why the band 16 is set to 0.1 to 10Hz is because the maximum speed of human movement is less than 10H2, so it is useful to set the band in this way, noise caused by commercial frequencies, vibrations of cars, and infrared rays. Noise output from the sensor (peak 5
(near 0 Hz) etc. (1) It is possible to remove only noise, but the peak hold circuits 17 to 20 hold the peak values of the output signals of the band pass filters 13 to 16 for a certain period of time 61, and their output signals a - h are shown in FIGS. 4(, 4) to (D), respectively. Comparators 21 to 24
compares the output signals of the peak bold circuits 17 to 2o with the threshold value, and sets the output signals i to It to "1" during the period when the threshold value is smaller. Therefore, in this case , the output signals S-1 of each comparator 21-24 are "1", respectively.
”, 0, “1”, and “a”. That is, the output signal irk of the comparator 21.23 corresponding to the seat where the passenger is seated is "1", and the output signal j and β of the comparator 22.24 corresponding to the seat where the passenger is not seated is "0". becomes.

The processing device 28 performs processing according to the flowchart shown in FIG. 5 based on the signals i to k applied via the data input section 25, and its operation will be explained below with reference to FIG. .

When the processing device 28 reads the signals 1-41, it calculates the address of the memory 27 to be accessed based on them. In this case, the processing device 28 calculates the address as shown in the following table.

Therefore, as described above, when an occupant is seated in the seat 40, 42, the signals i and k are "1", and the signals j and β are "0", address #2 is calculated.

When the address is calculated in this way, the processing device 28 reads the contents stored in the memory 27 at the calculated address. Each address of the memory 27 has a sixth address.
As shown in the figure, crosstalk amount C1 delay amount T1 attenuation amount A
is memorized, as mentioned above, seat 40
．． 42, the processing device 28 reads the contents stored at address #2 of the memory 27.

Now, assuming that the memory contents of address #2 are read, the processing device 28 generates a control signal m1, which sets the crosstalk amount C to -5 dB, based on the read memory contents. Delay time of R T t-1-
A control signal n with a duration of 2 m sec and a control signal Ot with an attenuation amount A k 4 dE of the right side signal R are created, and these control signals m=ot-data output section 26t- are transmitted to the attenuator 61, the delay circuit 32, Add to attenuator 65.

Accordingly, the attenuator 61, the delay circuit 32, and the attenuator 65 are controlled, and the amount of crosstalk C is set to 15 dE, the amount of delay T is set to 1.2 mga6, and the amount of attenuation A is set to 4 dE.

In this way, when the crosstalk amount C1 delay amount T1 attenuation amount A is set, the speaker 36.38 moves to the right in a certain number of songs, so the It can give a sufficient stereo feeling. Hereinafter, the processing device 28 performs the same processing as described above every time the output signals S-1 of the comparators 21-24 change.

FIG. 7 is a block diagram of a main part of another embodiment of the present invention, which is designed to reduce the influence of noise output from an infrared sensor due to vibrations of a vehicle.

In the figure, 1' is a shielding plate, 5' is a pyroelectric infrared sensor with the same characteristics as the infrared sensor 5, and 40 is a differential amplifier. The same reference numerals as in the other figures 2 represent the same parts. ing.

The shielding plate 1' is attached to the front of the light-receiving part of the infrared sensor 5' to prevent light from entering the light-receiving part, so that only noise signals corresponding to vibrations of the car are output from the infrared sensor 5'. That will happen. Therefore, the infrared sensor 5
, 5' are differentially amplified by the differential amplifier 40, the noise signal frequently generated due to the vibration of the car is removed because it is an in-phase component.

Although it was not explained in the above-mentioned embodiment, when luggage etc. are placed on the seat, infrared rays from the luggage will be incident on the infrared sensor, but normally the amount of infrared rays radiated from the luggage is is a background that has almost the same temperature as the luggage, that is, it is almost equal to that radiated from the car seat, and when the car vibrates, the distance between the infrared sensor and the luggage must be almost constant, and the radiation incident on the infrared sensor Since the amount of infrared rays generated by the passenger seat is approximately constant, the output signal of the infrared sensor is approximately zero, so even if luggage is placed on the seat, there will be no malfunction.

Effects of the Invention The present invention provides detection means (in the embodiment, comparators 21 -
24, etc.), and a control means (in the embodiment, consisting of a processing device 28, an attenuator 31, 33, a delay circuit 52, etc.) for controlling the sound field based on the detection result of the detection means. Therefore, there is an advantage that sound field control can be automatically performed depending on the seating position of the occupant.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the present invention, Fig. 2 is a block diagram of an embodiment of the present invention, Fig. 3 is a diagram showing the mounting positions of an infrared sensor and a speaker, and Figs. 4 (A) to (D). 2 is an explanatory diagram of the operation of FIG. 2, FIG. 5 is a flowchart showing the processing contents of the processing device, FIG. 6 is a diagram showing the storage contents of the memory, and FIG. 7 is a main part configuration diagram of another embodiment of the present invention. It comes out. 1 to 4 are infrared transmission filters, 1' is a shielding plate, 5 to 8,
5' is an infrared sensor, 9-12.34.35 is an amplifier,
13 to 16 are band pass filters, 17 to 20 are peak hold circuits, 21 to 24 are comparators, 25 is a data input section, 26 is a data output section, 27 is a memory, 28 is a processing device, 29 is an audio device body% JO is a polarity inversion circuit, 31.33 is an attenuator, 62 is a delay circuit, 66~
'39 has a speaker. Patent Applicant: Fujitsu Ten Ltd. Representative Patent Attorney Gobe Tamamushi (1 other person) Figure 4 Figure 5 603- Figure 6 Figure 7

Claims (1)

[Claims] In a sound field control device that controls the sound field of an in-vehicle audio device, an infrared sensor is installed corresponding to each seating position of an occupant, and the presence or absence of an occupant at each seating position is determined based on the output signal of the infrared sensor. What is claimed is: 1. A sound field control device comprising: detection means for detecting □, and control means for controlling sound field based on the detection result of the detection means.