JP2013116712A - Acoustic device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reproduce a tone color near to an actual operation sound.SOLUTION: This acoustic device 1 for a vehicle includes: a control circuit 2 having a plurality of signal output parts 21a and 21b for individually outputting a plurality of acoustic component signals of becoming constant in the duty ratio and controlling a frequency of the respective acoustic component signals output from the respective signal output parts 21a and 21b; an adding circuit 4 for generating an acoustic composite signal by adding the mutual respective acoustic component signals output from the respective signal output parts 21a and 21b mutually superposing amplitude of these acoustic component signals; and an acoustic part 5 for converting the acoustic composite signal generated by the adding circuit 4 into an artificial operation sound. The control circuit 2 generates a main acoustic component signal controlled in the frequency corresponding to a main sound wave component of becoming maximum in a sound pressure level in a specific operation sound and a sub-acoustic component signal controlled in the frequency corresponding to a sub-sound wave component smaller in the sound pressure level than the main acoustic component signal in the specific operation sound, as the acoustic component signal.

Description

  The present invention relates to a vehicle acoustic device.

  2. Description of the Related Art Conventionally, a vehicle acoustic device is known as one of devices that provide auditory information in a vehicle. For example, some acoustic devices for vehicles provide an operating sound of a mechanical relay that blinks a direction indicator lamp as a turn sound at the time of blinking. However, in recent years, with the fact that mechanical relays are no longer used for blinking direction indicator lamps, there is a need to simulate the turn sound.

  Therefore, in the vehicle acoustic device disclosed in Patent Document 1, a plurality of acoustic component signals having different frequencies are generated by controlling a plurality of transmission circuits by a control circuit in order to reproduce a pseudo operation sound. These acoustic component signals are synthesized in time series and output from a speaker as an acoustic unit.

Japanese Patent No. 4335578

  Now, the actual operation sound to be reproduced is a sound in which sound waves having a plurality of frequencies are overlapped. On the other hand, the operating sound reproduced in the vehicle acoustic device disclosed in Patent Document 1 is controlled so that the amplitude of each acoustic component signal output from each transmission circuit is not superimposed. Thus, the sound is simply a single frequency sound wave connected in time series. In other words, the operating sound output from the vehicle acoustic device disclosed in Patent Document 1 does not overlap sound waves having a plurality of frequencies. For this reason, there is a problem that a difference in timbre between the operation sound to be reproduced and the pseudo operation sound becomes large, which gives the vehicle occupant an uncomfortable feeling.

  Then, when the present inventor conducted earnest research for solving such problems, the following became clear. For example, when a dedicated audio IC is used, a sound waveform based on data acquired from the memory is generated and output to the amplifier IC, so that the operation sound to be reproduced can be faithfully reproduced. However, there is a problem that a vehicle acoustic device using a dedicated audio IC is generally expensive.

  On the other hand, by outputting a pulse width modulation signal from the pulse pattern generator port provided in the control circuit, an analog signal converted by integrating the output signal by a relatively inexpensive general-purpose integration circuit is output to the acoustic unit. By doing so, it is also possible to faithfully reproduce the operation sound to be reproduced. However, in order to output a pulse width modulation waveform from the pulse pattern generator port, a complicated calculation is required by the control circuit, and there is a problem that the processing load of the control circuit becomes large.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a vehicular acoustic device that artificially reproduces a timbre close to an actual operating sound while reducing the processing load of the control circuit. , To provide.

  The invention according to claim 1 is a vehicular acoustic device that artificially reproduces a specific operation sound in a vehicle, and a plurality of signal outputs that individually output a plurality of acoustic component signals having a constant duty ratio. A control circuit that controls the frequency of each acoustic component signal that is output from each signal output unit, and each acoustic component signal that is output from each signal output unit is added together, and the amplitude of these acoustic component signals is determined. The control circuit includes an adder circuit that generates a sound synthesis signal by superimposing each other, and an acoustic unit that converts the sound synthesis signal generated by the adder circuit into a pseudo operation sound. The main sound component signal that is controlled to the frequency corresponding to the main sound component with the maximum pressure level, and the frequency corresponding to the sub sound component whose sound pressure level is lower than the main sound component signal in a specific operating sound And a sub sound component signal for controlling, respectively generated as sound component signal.

  In the first aspect of the invention, the acoustic component signals individually output from the signal output units of the control circuit are added by the adding circuit, so that the amplitudes of the acoustic component signals are superimposed on each other. Thus, one acoustic synthesis signal is generated. Therefore, the operation sound (hereinafter referred to as “pseudo operation sound” in the column of solution means) that is reproduced in a pseudo manner by converting the sound synthesis signal by the sound unit is included in each sound component signal before superposition. The sound waves having the corresponding frequencies overlap each other. Here, in particular, the main acoustic component signal and the sub acoustic component signal among the acoustic component signals are respectively smaller than the main acoustic wave component and the corresponding frequency of the main acoustic wave component of the maximum sound pressure level constituting the specific operation sound to be reproduced. It is controlled to the corresponding frequency of the subsonic wave component constituting the specific operation sound at the sound pressure level. As a result, the pseudo operation sound is reproduced by overlapping the main sound component and the sub sound component of the frequency corresponding to the main sound component signal and the sub sound component signal. A tone close to the specific operation sound to be reproduced including

  Furthermore, in the first aspect of the present invention, each acoustic component signal individually output from each signal output unit of the control circuit is a pulse width modulation signal as long as it has a constant duty ratio. Compared to the case, the processing load of the control circuit can be reduced. Moreover, even if the duty ratio of each acoustic component signal is constant, by adding the respective acoustic component signals having different frequencies and converting them to pseudo operating sounds, it is possible to realize a timbre close to the specific operating sound to be reproduced as described above. Therefore, it is not necessary to use a dedicated audio IC.

  According to the invention described in claim 1 as described above, it is possible to provide a vehicular acoustic device that reproduces a timbre close to an actual specific operation sound with a simulated operation sound while reducing the processing load of the control circuit. It is.

  According to the second aspect of the present invention, the frequency of the sub acoustic component signal is higher than the frequency of the main acoustic component signal, and the control circuit controls the main acoustic component to an amplitude corresponding to the sound pressure level of the main acoustic component. An acoustic component signal and a sub-acoustic component signal controlled to an amplitude corresponding to the sound pressure level of the sub-sonic component are generated as acoustic component signals. The main sound component signal and the sub-acoustic component signal of the present invention respectively correspond to the corresponding amplitude of the main sound component of the maximum sound pressure level constituting the specific operation sound to be reproduced and the sound pressure level smaller than the main sound component. It is controlled to the corresponding amplitude of the subsonic wave component constituting the specific operation sound. As a result, the pseudo operation sound is reproduced by overlapping the main sound wave component and the sub sound wave component corresponding to not only the frequency but also the amplitude of each sound component signal. On the other hand, the reproducibility of the timbre can be improved.

  According to the third aspect of the present invention, the control circuit controls the frequency of the sub-acoustic component signal to an integral multiple of the fundamental frequency, where the frequency of the main acoustic component signal is the fundamental frequency. Here, in general, the frequency of the subsonic wave component having a low sound pressure level as a harmonic component for the specific operation sound to be reproduced is an integral multiple of the frequency of the main sound wave component of the maximum sound pressure level. Therefore, in the present invention, the frequency of the sub-acoustic component signal corresponding to the subsonic component is controlled to be an integral multiple of the fundamental frequency, which is the frequency of the main acoustic component signal corresponding to the main acoustic component. According to this, the pseudo operation sound converted from the sound synthesis signal obtained by synthesizing the main sound component signal and the sub sound component signal has a sub sound component whose frequency is an integer multiple of the main sound component, that is, a harmonic component. Since they overlap, the reproducibility of the timbre for the specific operation sound can be improved.

  According to the invention described in claim 4, the control circuit variably controls the frequency of the main sound component signal so as to correspond to the change in the frequency of the main sound wave component in the specific operation sound. In the present invention, the frequency of the main sound component signal is made variable so as to correspond to the frequency change of the main sound component in the specific operation sound to be reproduced, thereby improving the reproducibility of the timbre of the pseudo operation sound with respect to the specific operation sound. To do.

  According to the invention described in claim 5, the control circuit variably controls the frequency of the main acoustic component signal and the signal characteristic of the sub acoustic component signal so as to correspond to the time when the frequency of the main sound component changes. In this invention, not only the frequency of the main acoustic component signal but also the signal characteristic of the sub acoustic component signal can be made to correspond to the frequency change of the main acoustic component by variable control, so that the reproducibility of the timbre of the pseudo operating sound with respect to the specific operating sound Is further improved. Therefore, the subacoustic component signal does not change following the frequency change of the main acoustic component signal, so that it is possible to prevent the vehicle occupant from feeling uncomfortable with respect to the timbre of the pseudo operation sound.

  According to the invention described in claim 6, the plurality of signal output units are one main signal output unit that outputs the main acoustic component signal and two or more sub signal output units that output the sub acoustic component signal. Either one. In this invention, the main sound component signal output from one main signal output unit and each sub sound component signal output from two or more sub signal output units are synthesized, and the pseudo operation sound is generated as the sound synthesis signal. Will be converted to. As a result, for the pseudo operation sound, one main sound wave component corresponding to the main sound component signal and two or more sub sound wave components corresponding to each sub sound component signal are overlapped and reproduced. The reproducibility of the timbre can be improved with respect to the specific operation sound including the sound wave component.

  According to the seventh aspect of the present invention, the apparatus includes a plurality of integration circuits that individually integrate each acoustic component signal output from each signal output unit, and the adder circuit is integrated after being integrated by each integration circuit. Each acoustic component signal is added. In the present invention, each acoustic component signal is individually integrated by the integrating circuit, so that the high frequency component is smoothed and then subjected to the adding process by the adding circuit. Therefore, when each of the acoustic component signals is synthesized by such an adder circuit and converted into a pseudo operation sound as an acoustic synthesis signal, the pseudo operation sound is reproduced without noise that is annoying to the vehicle occupant. Therefore, the tone is brought closer to the specific operating sound.

It is a block diagram which shows 1st embodiment of the audio equipment for vehicles of this invention. 1 is output from each signal output unit of FIG. 1, and (a) a main acoustic component signal before input to the integration circuit, (b) a main acoustic component signal converted by the integration circuit, and (c) before input to the integration circuit. 4A is a time chart of the sub-acoustic component signal, (d) the sub-acoustic component signal converted by the integrating circuit, and (e) the acoustic synthetic signal converted by the adding circuit. It is a block diagram which shows 2nd embodiment of the audio equipment for vehicles of this invention. It is a block diagram which shows the modification of 1st embodiment of the audio equipment for vehicles of this invention. 1 is output from each signal output unit in FIG. 1, and (a) the main acoustic component signal before input to the integration circuit, (b) the main acoustic component signal output from the integration circuit, and (c) before input to the integration circuit. 6 shows a modification of the time chart of the sub-acoustic component signal, (d) the sub-acoustic component signal output from the integration circuit, and (e) the acoustic synthesis signal output from the addition circuit.

  Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. In addition, the overlapping description may be abbreviate | omitted by attaching | subjecting the same code | symbol to the corresponding component in each embodiment. When only a part of the configuration is described in each embodiment, the configuration of the other embodiment described above can be applied to the other part of the configuration. In addition, not only combinations of configurations explicitly described in the description of each embodiment, but also the configurations of a plurality of embodiments can be partially combined even if they are not explicitly specified unless there is a problem with the combination. .

(First embodiment)
As shown in FIG. 1, the vehicle acoustic device 1 according to the first embodiment of the present invention includes a control circuit 2, a pair of integration circuits 3a and 3b, an addition circuit 4, an acoustic unit 5, and resistance elements R1 and R2. As a specific operation sound in the vehicle, a turn sound when the direction indicator lamp blinks is reproduced in a pseudo manner. In the following description, the turn sound as the operation sound reproduced by the vehicle acoustic device 1 is referred to as “pseudo operation sound”. Further, in the following description, the turn sound to be reproduced with respect to the simulated operation sound is referred to as “reproduction target sound”.

  The control circuit 2 includes a microcomputer 20 including a CPU 20a and a memory 20b, and a pair of signal output units 21a and 21b that are electrically connected thereto. In the microcomputer 20, the CPU 20 a executes the computer program stored in the memory 20 b to generate acoustic component signals that are individually output from the signal output units 21 a and 21 b. Each signal output part 21a, 21b is comprised from PPG (Pulse PatternGenerator) or S / G (Sound Generator), etc., and outputs the acoustic component signal produced | generated by the microcomputer 20 as a digital signal synchronizing mutually.

  Each of the integration circuits 3a and 3b is a general-purpose CR filter composed of, for example, a capacitor and a resistance element, and is electrically connected to the corresponding signal output units 21a and 21b. Each integration circuit 3a, 3b integrates each acoustic component signal output from the corresponding signal output unit 21a, 21b, and converts it from a digital signal to an analog signal. At this time, each integration circuit 3a, 3b delays the response speed of rising of the input digital signal and synchronizes the output timing of the analog signal with each other in accordance with the set time constant.

  The adder circuit 4 is a general-purpose adder circuit composed of, for example, an operational amplifier, and is electrically connected to both the integrating circuits 3a and 3b. The adder circuit 4 adds the acoustic component signals converted into analog signals by the integrating circuits 3a and 3b to generate one acoustic synthesis signal. Since each acoustic component signal before being added by the adding circuit 4 is synchronized with the output timing from the signal output units 21a and 21b and the output timing from the integrating circuits 3a and 3b as described above, One acoustic synthesis signal corresponding to the reproduction target sound can be generated by the addition.

  The acoustic unit 5 includes an amplifier 50, a speaker 51, and the like, and is arranged with the output unit of the speaker 51 facing the driver's seat. The amplifier 50 is, for example, a linear amplifier type amplifier IC or the like, and is electrically connected to the adder circuit 4. The amplifier 50 amplifies the amplitude of the acoustic synthesis signal generated by the adder circuit 4 and outputs the amplified signal to the speaker 51. The speaker 51 is a general-purpose vehicle speaker and is electrically connected to the amplifier 50. The speaker 51 converts the amplified sound synthesis signal output from the amplifier 50 into each sound wave component of the pseudo operation sound and outputs it to the vehicle. That is, the frequency and sound pressure level of each sound wave component of the simulated operating sound reproduced and output from the speaker 51 correspond to the frequency and amplitude of the sound synthesis signal.

The resistor element R1 is provided on a path that electrically connects the integrating circuits 3a and 3b and the adder circuit 4, and the resistor element R2 is provided between the path and the ground terminal of the vehicle. By adjusting the resistance values of the resistance elements R1 and R2, the amplitudes of the acoustic component signals input from the integration circuits 3a and 3b to the addition circuit 4 are adjusted.
(Generation of simulated operating sound)
Generation | occurrence | production of the pseudo operation sound by the vehicle audio apparatus 1 of 1st embodiment mentioned above becomes a characteristic thing according to this invention, and the detail is demonstrated below.

  As shown in FIG. 2A, the control circuit 2 generates a main acoustic component signal Sm as an acoustic component signal output from one signal output unit 21a. At this time, with respect to the main acoustic component signal Sm, the control circuit 2 determines the frequency and amplitude corresponding to the frequency of the main sound component and the sound pressure level at which the sound pressure level becomes maximum when frequency analysis of the sound to be reproduced is performed, It is generated with the duty ratio. Here, in particular, the control circuit 2 variably controls the frequency of the main acoustic component signal Sm so as to correspond to the frequency change of the main sound component in the reproduction target sound. As a result, in the present embodiment, the frequency of the main acoustic component signal Sm decreases at the timing tv of the frequency change of the main sound component as shown in FIG. Furthermore, the control circuit 2 of the present embodiment controls the continuous output period Pm as shown in FIG. 2A as the “signal characteristic” of the main acoustic component signal Sm so as to be substantially equal to the duration of the reproduction target sound. .

  On the other hand, as shown in FIG. 2C, the control circuit 2 generates a sub acoustic component signal Ss as an acoustic component signal output from the other signal output unit 21b. Here, in particular, for the sub-acoustic component signal Ss, the control circuit 2 performs a frequency analysis of the sound to be reproduced, and the frequency corresponding to the frequency of the sub-sonic component and the sound pressure level whose sound pressure level is smaller than the main acoustic component signal sm. And an amplitude and a constant duty ratio. In particular, for the frequency of the sub-acoustic component signal Ss, the control circuit 2 is an integer corresponding to the sub-sonic component in the reproduction target sound with respect to the fundamental frequency of the main acoustic component signal Sm corresponding to the main sound component in the reproduction target sound. It is controlled to be higher than the fundamental frequency so as to be doubled. Further, the control circuit 2 controls the amplitude of the sub acoustic component signal Ss so as to be smaller than the amplitude of the main acoustic component signal Sm corresponding to the main sound component in the reproduction target sound. Furthermore, the control circuit 2 of the present embodiment can change the continuous output period Ps as shown in FIG. 2C as the “signal characteristics” of the sub-acoustic component signal Ss in accordance with the frequency change of the main sound component in the reproduction target sound. Control. As a result, the continuous output period Pc of the sub acoustic component signal Sm is shortened at the timing tv of the frequency change of the main sound wave and the main acoustic component signal Sm as described above.

  The integrating circuits 3a and 3b that receive the corresponding acoustic component signals Sm and Ss from the signal output units 21a and 21b of the control circuit 2 as described above are shown in FIGS. 2 (b) and 2 (c). Sm and Ss are individually integrated. As a result, the acoustic component signals Sm and Ss output from the integrating circuits 3a and 3b are obtained by smoothing high frequency components according to the time constant of the CR filter.

  Further, the adder circuit 4 that receives the acoustic component signals Sm and Ss after being integrated by the integrating circuits 3a and 3b superimposes the amplitudes of the acoustic component signals Sm and Ss on each other as shown in FIG. An acoustic synthesis signal Sc in which the signals Sm and Ss are added together is generated. Here, in particular, the superposition of amplitude is to combine the sub acoustic component signal Sm of the continuous output period Ss within the period Pm and shorter than the period Pm with the main acoustic component signal Sm of the continuous output period Pm. Thus, it is realized as in the period Pc of FIG. Therefore, in the present embodiment, the amplitude overlapping period Pc is substantially equal to the continuous output period Ps of the sub-acoustic component signal Sm.

  The sound synthesis signal Sc synthesized by the adder circuit 4 is converted by the sound unit 5 and output from the speaker 51 of the sound unit 5 into the vehicle, so that the main sound component and the sub sound component of the reproduction target sound are obtained. It is reproduced as a pseudo operation sound including

(Function and effect)
The effect by the vehicle audio apparatus 1 of 1st embodiment mentioned above is demonstrated in detail below.

  According to the first embodiment, the acoustic component signals Sm and Ss individually output from the signal output units 21a and 21b of the control circuit 2 are added by the adder circuit 4 so that the signals Sm and Ss are The amplitudes are superimposed on each other to generate one acoustic synthesis signal Ss. According to this, the pseudo operation sound that is simulated and reproduced by converting the acoustic synthesis signal Ss by the acoustic unit 5 includes sound waves having frequencies corresponding to the acoustic component signals Sm and Ss before superposition. It will overlap. Here, in particular, the main acoustic component signal Sm and the sub acoustic component signal Ss are reproduced with the corresponding frequency of the main sound component of the maximum sound pressure level constituting the sound to be reproduced and the sound pressure level smaller than the main sound component, respectively. It is controlled to the corresponding frequency of the subsonic wave component constituting the target sound. As a result, the pseudo operation sound is reproduced by overlapping the main sound component and the sub sound component of the frequencies corresponding to the main sound component signal Sm and the sub sound component signal Ss. It is possible to realize a timbre close to the target sound to be reproduced.

  In addition, according to the first embodiment, since each of the acoustic component signals Sm and Ss individually output from the signal output units 21a and 21b of the control circuit 2 may be signals having a constant duty ratio, Compared with the case of a pulse width modulation signal, the processing load of the control circuit 2 can be reduced. Moreover, even if the duty ratios of the acoustic component signals Sm and Sc are constant, the timbre close to the reproduction target sound as described above is obtained by adding the acoustic component signals Sm and Sc having different frequencies and converting them into a pseudo operation sound. Therefore, it is not necessary to use a dedicated audio IC.

  Furthermore, in the first embodiment, the main acoustic component signal Sm and the sub acoustic component signal Ss are respectively the corresponding amplitude of the main sound component of the maximum sound pressure level constituting the sound to be reproduced and the sound pressure level smaller than the main sound component. Are controlled to the corresponding amplitudes of the subsonic wave components constituting the reproduction target sound. As a result, the pseudo operation sound is reproduced by overlapping the main sound wave component and the sub sound wave component corresponding to not only the frequency but also the amplitude of each acoustic component signal Sm, Ss. On the other hand, the reproducibility of the timbre can be improved.

  Furthermore, according to the first embodiment, for the turn sound as the reproduction target sound, generally, the frequency of the subsonic wave component having a low sound pressure level as the harmonic component is higher than the frequency of the main sound wave component of the maximum sound pressure level. Will be an integer multiple. Therefore, in the first embodiment, the frequency of the sub-acoustic component signal Ss corresponding to the subsonic component is controlled to be an integral multiple of the fundamental frequency of the main acoustic component signal Sm corresponding to the main acoustic component. According to this, the pseudo operation sound converted from the sound synthesis signal Sc obtained by synthesizing the main sound component signal Sm and the sub sound component signal Ss is a sub sound component whose frequency is an integral multiple of the main sound component, that is, a harmonic. Since the wave components overlap, it is possible to improve the timbre reproducibility for the reproduction target sound.

  In addition, in the first embodiment, the frequency of the main acoustic component signal Sm can be made to correspond to the frequency change of the main sound component in the reproduction target sound by the variable control, and therefore the reproducibility of the timbre of the pseudo operation sound with respect to the reproduction target sound. Can be improved. At the same time, in the first embodiment, not only the frequency of the main acoustic component signal Sm but also the continuous output period Ps as the “signal characteristic” of the sub acoustic component signal Ss is made to correspond to the frequency change of the main sound component by variable control. Therefore, the reproducibility of the timbre of the pseudo operation sound with respect to the reproduction target sound can be further improved. Therefore, in spite of the frequency change of the main acoustic component signal Sm, the sub acoustic component signal Ss does not follow and change, so that it is possible to prevent the vehicle occupant from feeling uncomfortable with respect to the timbre of the pseudo operation sound.

  In addition, in the first embodiment, the acoustic component signals Ss and sm are individually integrated by the corresponding integration circuits 3a and 3b, respectively, so that the high frequency components are smoothed, and then the addition circuit 4 It will be used for addition processing. According to this, each of the acoustic component signals Sm and Sc is synthesized by the adder circuit 4 and converted into the simulated operating sound as the acoustic synthesized signal Sc, so that the simulated operating sound is not annoying to the vehicle occupant. The noise is removed and the timbre is brought close to the reproduction target sound.

  As described so far, according to the first embodiment, there is provided the vehicle acoustic device 1 that reproduces the timbre close to the actual reproduction target sound by the pseudo operation sound while reducing the processing load of the control circuit 2. It is possible.

(Second embodiment)
As shown in FIG. 3, the second embodiment of the present invention is a modification of the first embodiment. In the vehicle acoustic device 101 of the second embodiment, the control circuit 102 is provided with two or more sub-signal output units 21b that output the sub-acoustic component signal Ss. Here, the sub-acoustic component signal Ss output from each sub-signal output unit 21b performs frequency analysis on the reproduction target sound within a range that satisfies the conditions of the frequency, amplitude, duty ratio, and continuous output period Pc described in the first embodiment. Are generated so as to correspond to two or more subsonic wave components having different frequencies.

  In the second embodiment, the number of sets of the integration circuit 3b and the resistance elements R1 and R2 is the same as the number of the sub signal output units 121b according to the two or more sub signal output units 21b. As a result, the sub-acoustic component signal Ss output from each sub-signal output unit 121b to each integrating circuit 3b and subjected to integration processing is output from the one main signal output unit 121a by the adding circuit 4 electrically connected to the integrating circuit 3b. The main sound component signal Sm output to the integration circuit 3a and integrated is synthesized. Then, a pseudo operation sound that is converted by the sound unit 5 and is output into the vehicle by the sound synthesis signal Ss obtained as a result of the synthesis is one main sound component corresponding to the main sound component signal Sm and each sub sound. Two or more subsonic wave components corresponding to the component signal Ss are reproduced in an overlapping manner. Therefore, the timbre reproducibility can be improved with respect to the reproduction target sound including two or more subsonic wave components together with one main sound wave component.

(Other embodiments)
Although a plurality of embodiments of the present invention have been described above, the present invention is not construed as being limited to these embodiments, and various embodiments and combinations can be made without departing from the scope of the present invention. Can be applied.

  Specifically, as for the integration circuits 3a and 3b, as shown in a modified example in FIG. 4 (which is a modified example of the first embodiment), a low pass using an inductor and a capacitor instead of the integration circuits 3a and 3b. The filters 203a and 203b may be employed, or the integration circuits 3a and 3b themselves may not be provided. Further, as shown in FIG. 5 showing a modification of the main acoustic component signal Sm (FIG. 5 shows a modification of the first embodiment), the control for making the frequency during the continuous output period Pm constant without changing is controlled. The circuit 1 or 101 may be used. Further, as shown in a modified example in FIG. 5 for the sub acoustic component signal Ss, the control circuits 1 and 101 perform control to substantially match the continuous output period Ps of the signal Ss with the continuous output period Pm of the main acoustic component signal Sm. You may do it. Furthermore, the frequency of the sub acoustic component signal Ss may be controlled by the control circuits 1 and 101 so as to be lower than the frequency of the main acoustic component signal Sm, or may be lower than the basic frequency of the main acoustic component signal Sm. Control may be performed by the control circuits 1 and 101 so as not to be an integral multiple of the fundamental frequency in a high range. In addition, as the “signal characteristics” of the sub-acoustic component signal Ss, the continuous output period Pm is variably controlled by the control circuits 1 and 101 according to the frequency change of the main sound component, for example, the frequency, amplitude, etc. The control circuits 1 and 101 may be variably controlled.

DESCRIPTION OF SYMBOLS 1,101 Vehicle acoustic device, 2,102 Control circuit, 3a, 3b Integration circuit, 4 Adder circuit, 5 Sound part, 21a Main signal output part, 21b Sub signal output part, 50 Amplifier, 51 Speaker, Pm, Ps Continuation Output period, Pc amplitude superposition period, Sm main sound component signal, Ss sub-acoustic component signal, Sc sound synthesis signal, tv frequency change timing

Claims (7)

A vehicle acoustic device that simulates a specific operation sound in a vehicle,
A control circuit that has a plurality of signal output units that individually output a plurality of acoustic component signals having a constant duty ratio, and that controls the frequency of each acoustic component signal output from each of the signal output units;
An addition circuit that generates an acoustic synthesis signal by adding the acoustic component signals output from the signal output units and superimposing the amplitudes of the acoustic component signals with each other;
An acoustic unit that converts the acoustic synthesis signal generated by the addition circuit into a pseudo operation sound;
The control circuit includes a main acoustic component signal that controls a frequency corresponding to a main sound wave component having a maximum sound pressure level in the specific operating sound, and a sound pressure level in the specific operating sound that is higher than that of the main acoustic component signal. And a sub-acoustic component signal controlled to a frequency corresponding to a smaller sub-sonic component, respectively, as the acoustic component signal. The frequency of the sub-acoustic component signal is higher than the frequency of the main acoustic component signal;
The control circuit, the main acoustic component signal that controls to an amplitude corresponding to the sound pressure level of the main sound component, and the sub acoustic component signal that controls to an amplitude corresponding to the sound pressure level of the sub sound component, The vehicle acoustic device according to claim 1, wherein each of the acoustic components is generated as the acoustic component signal.   3. The vehicle according to claim 1, wherein the control circuit controls the frequency of the sub-acoustic component signal to an integral multiple of the basic frequency when the frequency of the main acoustic component signal is a fundamental frequency. 4. Acoustic device.   4. The control circuit according to claim 1, wherein the control circuit variably controls the frequency of the main sound component signal so as to correspond to a change in the frequency of the main sound component in the specific operation sound. The vehicle acoustic device according to Item.   5. The control circuit according to claim 4, wherein the control circuit variably controls a frequency of the main acoustic component signal and a signal characteristic of the sub acoustic component signal so as to correspond to a change in the frequency of the main acoustic wave component. Vehicle acoustic device.   The plurality of signal output units are any one of one main signal output unit that outputs the main acoustic component signal and two or more sub signal output units that output the sub acoustic component signal. The vehicle acoustic device according to any one of claims 1 to 5, wherein the vehicle acoustic device is characterized. A plurality of integration circuits that individually integrate each of the acoustic component signals output from each signal output unit,
The vehicular acoustic device according to any one of claims 1 to 6, wherein the adding circuit adds the acoustic component signals after being integrated by the integrating circuits.

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