JPH06109071A - Vibration reducing device for vehicle - Google Patents

Abstract

PURPOSE:To efficiently carry out the vibration reduction control for an engine as a whole by throttling the order component of a control object, for a vibration reducing device for a vehicle which generates the control signal (s) for reducing the engine vibration detected by a microphone, on the basis of the error signal supplied from the microphone. CONSTITUTION:A vibration reducing device for a vehicle is equipped with a signal correcting circuit 29a for extracting the error signal m1 consisting of the frequency component having a prescribed number of order of the engine revolution cycle among the error signal m0 supplied from a microphone 10 and a control calculation part 25 for generating the control signal (s) for reducing the engine vibration which consists of the frequency component, among the engine vibration detected by the microphone 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle vibration reducing device, and more particularly to reducing a vehicle vibration by vibrating the same amplitude in a phase opposite to the vehicle vibration by an actuator provided with a specific vibration element of the vehicle. Regarding the improvement of what I did.
In the present invention, the vibration includes not only pure vibration of the vehicle body but also noise.

[0002]

2. Description of the Related Art Conventionally, as an active type vehicle vibration reducing apparatus, a reference signal corresponding to a vibration generated by an in-vehicle engine is generated as disclosed in, for example, Japanese Patent Publication No. 56-501062. A reference signal generator, an adaptive filter that generates a control signal that has an opposite phase and the same amplitude as the reference signal generated by this reference generator, and the vehicle body that receives the control signal generated by this adaptive filter. Vibration generating means such as a vibrating speaker, vibration detecting means such as a microphone that detects vibration of the vehicle body or vehicle interior air, and the coefficient of the adaptive filter so that the error signal detected by the vibration detecting means is minimized. LMS (Least MeanSquare Metho)
d (= least squares method) algorithm operation means is known.

That is, the reference signal generator detects an ignition pulse signal corresponding to engine vibration, and generates a reference signal as a digital signal from the ignition pulse signal. This reference signal is input to the adaptive filter, the gain and phase of the reference signal are adjusted in the adaptive filter, and the engine vibration and the vibration generated by the vibration generating means cancel each other at the position where the vibration detecting means is arranged. Such a control signal is generated, the control signal is output to the vibration generating means, and the vibration is output from the vibration generating means.

[0004]

By the way, for example, the vibration characteristics of the vibration generated from the engine differ depending on the number of cylinders of the engine, the cylinder arrangement method, and the like.
It is well known that reducing only a specific frequency component has a substantially considerable vibration reducing effect. For example, in an FF vehicle in which an inline 4-cylinder engine is placed horizontally, the vibration corresponding to the secondary component of the engine speed has a level that is prominent with respect to other components. In that case, the secondary component By simply reducing the vibration of, the engine vibration as a whole becomes surprisingly quiet. However, in the conventional vibration reduction device, since the vibration detected by the vibration detection means is uniformly controlled, the vibration reduction control is not efficiently performed as a whole.

In addition to vibrations to be controlled, such as engine vibrations, there are vibrations that should not be controlled, such as audio sounds of vehicle audio equipment. However, in the past, since all the vibrations detected by the vibration detecting means are controlled, the more the control performance is improved, the more the audio sound is erased.
The vibration reduction control may have an adverse effect.

Further, looking at engine vibration, for example, a pleasant exhaust sound when the engine speed rises may be preferable in order to experience the acceleration of the vehicle. However, in the past, only the intention was to suppress the vibration, and there was a lack of the viewpoint of emphasizing the necessary vibration or producing a preferable vibration condition.

The present invention has been made in view of the above points, and it is an object of the present invention to reduce the vibration of the vehicle as a whole when the vibration of the vehicle is to be reduced. In this way, the non-controlled object is prevented from being muted, and further, the vibration condition can be rendered.

[0008]

In order to achieve the above object, in the invention of claim 1, the output signal from the vibration detecting means is corrected by increasing or decreasing the predetermined frequency component and input to the control means.

Specifically, in the present invention, as shown in FIG. 1, the first vibration detecting means 18 for detecting the vibration information of the vibration source in the vehicle, and the vibration from the vibration source are set at a predetermined position in the vehicle compartment. Second vibration detecting means 10 for detecting the
The second vibration detecting means 1 receives the output of the vibration detecting means 10.
The second vibration detecting means 1 receives the output of the signal correcting means 29 for correcting the vibration signal m0 output from 0 to the predetermined signal m1 and the outputs of the first vibration detecting means 18 and the signal correcting means 29.
Control means 25 for generating a control signal s for changing the vibration detected at 0 into a predetermined vibration, and this control means 25
And a vibration generating means 11 for generating a vibration based on the output of.

According to a second aspect of the invention, in the first aspect of the invention, the first vibration detecting means 18 is configured to detect the cycle of engine rotation as the vibration information of the engine in the vehicle. In addition, the signal correcting means 29 controls the predetermined signal m1 of the vibration signal m0 from the second vibration detecting means 10 to be a frequency component of a predetermined order in the cycle of engine rotation detected by the first vibration detecting means 18. To extract. Then, the control unit 25 is configured to generate the control signal s for reducing the engine vibration including the frequency component of the predetermined order in the engine vibration detected by the second vibration detection unit 10.

According to a third aspect of the invention, there is provided the sound detecting means 9 according to the first aspect of the invention, for detecting the information of the non-control target sound in the vehicle. Further, the signal correcting means 29 extracts a predetermined signal m1 of the vibration signal m0 from the second vibration detecting means 10 and having a frequency component other than the frequency component of the sound signal a outputted from the sound detecting means 9. To configure. Then, the control unit 25 is configured to generate the control signal s for reducing the vibrations of the frequency components other than the frequency component of the sound signal a, of the vibrations detected by the second vibration detection unit 10. Constitute.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the first vibration detecting means 18 is configured to detect the cycle of engine rotation as the vibration information of the engine in the vehicle. Further, the signal correction means 29 has a vibration target waveform set in advance in accordance with the cycle of engine rotation, and the vibration signal m0 from the second vibration detection means 10 is detected by the first vibration detection means 18. The predetermined waveform m1 is synthesized by superposing the target waveforms of vibrations according to the engine rotation period. Then, the control unit 25 is configured to generate the control signal s for changing the engine vibration detected by the second vibration detection unit 10 to the engine vibration set in advance according to the cycle of the engine rotation.

[0013]

With the above construction, the first aspect of the invention is the first aspect.
The vibration detection means 18 detects the vibration information of the vibration source of the vehicle, and the output signal of the first vibration detection means 18 is input to the control means 25.

Further, the vibration of the vibration source is detected by the second vibration detecting means 10 at a predetermined position in the vehicle compartment. The vibration signal m0 output from the second vibration detection means 10 is input to the signal correction means 29, is corrected to a predetermined signal m1 by the signal extraction means 29, and the corrected signal m1 is input to the control means 25. . The control means 25 generates a control signal s for changing the vibration detected by the second vibration detecting means 10 into a predetermined vibration based on the corrected signal m1. At this time, only the frequency component of the signal m1 is to be controlled, while vibrations composed of frequency components other than the frequency component are not to be controlled. The control signal s of the control means 25 is input to the vibration generating means 11 and the vibration generating means 11 causes vibration. Between the vibration from the vibration generating means 11 and the vibration of the vibration source of the vehicle detected by the first vibration detecting means 18, frequency components having mutually opposite phases cancel each other out, and frequency components having the same phase with each other. Mutual strengthening. On the other hand, among the vibrations from the vibration source, the vibrations composed of the frequency components as the non-controlled objects are not affected by the vibrations of the vibration generating means 11, and the amplitude value is maintained as it is. As a result, the vibration at the predetermined position in the vehicle compartment detected by the second vibration detecting means 10 is changed so as to be reduced, increased or maintained for each predetermined frequency component.

According to the second aspect of the invention, the vibration signal m of the second vibration detecting means 10 is caused by the signal extracting means 28 which receives the output of the first vibration detecting means 18 for detecting the cycle of the engine rotation.
Of 0, a predetermined signal m1 composed of a frequency component of a predetermined order in the cycle of engine rotation detected by the first vibration detection means 18 is extracted and input to the control means 25. The control means 25 generates the control signal s for reducing the engine vibration including the frequency component. This control signal s is input to the vibration generating means 11 and vibration is generated by the vibration generating means 11, and this vibration and the vibration composed of the above frequency component of the engine vibration detected by the first vibration detecting means 18 are generated. Cancel each other out, and thus, among the engine vibrations at the predetermined positions in the vehicle compartment detected by the second vibration detecting means 10, only the engine vibrations having the frequency components of the predetermined order are reduced.

According to the third aspect of the invention, the sound detecting means 9 detects the information of the non-control target sound in the vehicle, and the sound signal a of the sound detecting means 9 is inputted to the signal extracting means 29.
The signal extracting means 29 extracts a predetermined signal m1 having a frequency component other than the frequency component of the sound signal a from the vibration signal m0 from the second vibration detecting means 10 and inputs it to the control means 25. . The control means 25 generates a control signal s for reducing frequency components other than the frequency component of the sound signal a. This control signal s
Is input to the vibration generating means 11, and the vibration of the frequency component is generated by the vibration generating means 11. This vibration and the vibration of the frequency component of the vibration detected by the second vibration detecting means 10 are The vibrations cancel each other out, and among the vibrations at the predetermined position in the vehicle compartment detected by the second vibration detecting means 10, only the vibrations having frequency components other than the frequency components included in the sound signal a are reduced.

In the invention of claim 4, the first vibration detecting means 1
In the signal correcting means 29, which receives the output of the first vibration detecting means 18, the cycle of the engine rotation is detected by 8, and the output signal m0 of the second vibration detecting means 10 is measured by the first vibration detecting means 18. The target waveforms corresponding to the cycle of the engine rotation are overlapped to synthesize a predetermined signal m1. The control means 25, to which the synthesized signal m1 is input, generates the control signal s based on the signal m1. The control signal s is input to the vibration generating means 11, the vibration is generated by the vibration generating means 11, and the engine vibration detected by the second vibration detecting means 10 is set in advance according to the engine rotation cycle. It was changed to vibration, which made it the second
The engine vibration at the predetermined position in the vehicle compartment detected by the vibration detecting means 10 becomes the engine vibration set above.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings starting from FIG.

(Embodiment 1) A vehicle vibration reducing apparatus according to Embodiment 1 reduces an engine vibration component of a predetermined order among engine vibrations detected at a predetermined position in a vehicle compartment. As shown in FIG. In the figure, reference numeral 1 denotes a vehicle body, an engine room 2 is provided in the front part thereof, and a vehicle room 3 is provided in the front and rear central parts thereof. 4 is an engine arranged in the engine room 2,
The engine 4 is elastically supported by the vehicle body 1 via a mount (not shown) which elastically supports the lower portion thereof. In FIG.
5 is a steering wheel located at the front of the passenger compartment 3, 6
Is the front seat and 7 is the rear seat.

At a predetermined position in the vehicle compartment 3, a plurality of microphones 10, 10, ... And a plurality of speakers 11, 1.
1, ... Are respectively arranged (in the following description, for simplification, the microphone 10 and the speaker 11 are provided).
Will be described below). The microphone 10 constitutes second vibration detecting means 10 for detecting engine vibration at a predetermined position in the vehicle interior 3,
For example, the headrest portion of the front seat 6 and the side of the rear seat 7 are arranged at positions that are important for the occupant's feeling and hearing. On the other hand, the speaker 11 constitutes vibration generating means for generating vibration in the vehicle interior 3, and vibrates the air in the vehicle interior 3. Reference numeral 9 is an in-vehicle audio device arranged in the instrument panel 8 at the front end of the vehicle compartment 3.

The output signal of the microphone 10 is input to the controller 16 together with the information signal regarding the vibration emitted from the engine 4, and the controller 16 basically controls the speaker 11 based on a reference signal described later. Then, the engine vibration composed of frequency components of a predetermined order of the engine vibration is reduced.

The structure of the controller 16 is shown in FIG. In the figure, reference numeral 18 denotes an engine rotation cycle measurement circuit for measuring the engine rotation cycle based on the ignition signal of the air-fuel mixture in the engine 4.
8 produces a reference signal r related to the vibration of the engine 4. In this embodiment, the engine rotation cycle measuring circuit 18 constitutes the first vibration detecting means and detects the vibration information of the engine 4 which is the vibration source of the vehicle. Further, 22 is an amplifier for amplifying the error signal m as the vibration signal from the microphone 10 with a set gain, 23 is a low-pass filter for filtering the low frequency component of the error signal m amplified by the amplifier 22, and 24 is the low-pass filter. Error signal m of analog value filtered by the filter 23
Is an A / D converter that converts a signal m of a digital value.

Reference numeral 25 is a reference signal r from the engine rotation cycle measuring circuit 18 and an A / D converter 24.
The control calculation unit 25 receives the error signal m from the control unit 25. The control calculation unit 25 generates a control signal s for driving and controlling the speaker 11 so as to reduce the engine vibration detected by the microphone 10. I am configuring. 26 is a D / A converter for converting the control signal s generated by the control calculation unit 25 from a digital value to an analog value, and 27 is a low-frequency component of the control signal s from the D / A converter 26. The low-pass filter 28 is an amplifier that amplifies the control signal s filtered by the low-pass filter 27 with a set gain, and the control signal s amplified by the amplifier 28 is output to the speaker 11.

The control calculation unit 25 uses an LMS adaptive algorithm as an algorithm for generating the control signal s. FIG. 4 shows the internal configuration of the control arithmetic unit 25 using the LMS adaptive algorithm. In the figure, reference numeral 36 denotes a digital filter. The digital filter 36 outputs a control signal s from the control calculation unit 25, and then the speaker 11 is driven and controlled by the control signal s to change the vehicle vibration. Is detected by the microphone 10 and the error signal m is detected by the control calculator 25.
It consists of a transfer function model created based on the actual measurement results of the transfer characteristics up to the input. A convergence coefficient calculation circuit 38 calculates a convergence coefficient α · e for rewriting the filter coefficient according to the instantaneous value e of the error signal m from the microphone 10.
40 is a multiplier for multiplying the output value R of the digital filter 36 by the convergence coefficient α · e of the convergence coefficient calculation circuit 38, 4
In the adaptive filter 42, the filter coefficient fj is sequentially updated for each output of the multiplier 40 based on the output value α · e · R, and the reference signal is based on the updated filter coefficient fj. It outputs a control signal having the same amplitude as the opposite phase to r.

Next, the signal correction circuit 29a, which is a feature of the present invention, will be described with reference to FIG. The signal correction circuit 29a uses the same LMS adaptive algorithm as that of the control calculation unit 25 as an algorithm for correcting the error signal m. In the figure, reference numeral 30 denotes an arithmetic unit. In this arithmetic unit 30, the instantaneous value e0 of the error signal m0 input to the signal correction circuit 29a from the microphone 10 side is output from the signal correction circuit 29a to the control arithmetic unit 25. Instantaneous value e obtained by subtracting the instantaneous value e1 of the error signal m1
Output (e = e0-e1). Reference numeral 31 is a convergence coefficient calculation circuit. The convergence coefficient calculation circuit 31 calculates a convergence coefficient μ · e for rewriting the coefficient of the adaptive filter described below so that the instantaneous value e from the arithmetic unit 30 is minimized. . An oscillator 32 receives the reference signal r from the engine rotation period measuring circuit 18 and generates a sine wave having the same frequency as a frequency component of a predetermined order based on the engine rotation period. 33 is a multiplier. In the multiplier 33, the convergence coefficient μ · of the convergence coefficient calculation circuit 31 is
e is multiplied by the output value x of the oscillator 32. Reference numeral 34 is an adaptive filter. In this adaptive filter 34, the multiplier 33
The filter coefficient gi (0.ltoreq.i.ltoreq.I) is successively updated on the basis of the output value .mu..multidot.e.times.

The oscillator 32 generates a sine wave having the same frequency as the predetermined order component based on the engine rotation period T.
The oscillation frequency fp when the sine wave of the p-th order component is generated is fp = p / T [Hz]. For example, when the engine speed is 1200 rpm, the engine rotation frequency is 20 Hz.
The second component is 20 Hz, the second component is 40 Hz, and the third component is 6
It becomes 0 Hz.

Here, the output value x (n) of the oscillator 32 at a certain time n is defined as x (n) = sin (2πT · 1 / P · n / f) (where f: sampling frequency). The vector X (n) of the oscillator 32 is represented by the vector X (n) = [x (n), x (n-1), ..., X (nI)] The vector G of the adaptive filter 34 is represented by the vector G = [g0, g1, ..., gI] ^T , the instantaneous value e1 (n) of the error signal m1 input from the signal correction circuit 29a to the control calculation unit 25 is

[Equation 1] Becomes

On the other hand, the updating (optimization) of the adaptive filter 34 is performed by the following equation using the instantaneous value e (n) from the computing unit 30.
(E (n) = e0 (n) -e1 (n)) is minimized.

[0029]

[Equation 2] As a result, the error signal m output to the control calculation unit 25
The instantaneous value e1 (n) of 1 has the same phase and amplitude as the P-order component included in the instantaneous value e0 (n) of the error signal m0 input to the signal correction circuit 29a.

Therefore, in this embodiment, when the ignition signal of the engine 4 is input to the controller 16, the engine rotation cycle measuring circuit 18 generates an engine rotation cycle signal r corresponding to the engine vibration, and the control calculator 25 is operated. Entered in. Further, the engine vibration at a predetermined position in the vehicle interior 3 is detected by the microphone 10 in the vehicle interior 3, and the error signal m of the microphone 10 is also input to the control calculator 25. The control calculation unit 25 generates a control signal s for reducing engine vibration detected by the microphone 10, the control signal s is output to the speaker 11, and vibration is generated by the speaker 11. And the engine vibration cancel each other out, which reduces the engine vibration detected by the microphone 10 at a predetermined position in the vehicle interior 3.

At this time, the error signal m0 output from the microphone 10 is input to the signal correction circuit 29a,
The signal correction circuit 29a corrects the error signal m1 into a predetermined error signal, and the corrected error signal m1 is input to the control calculator 25. The control calculation unit 25 generates a control signal s for changing the engine vibration detected by the speaker 11 into a predetermined engine vibration based on the corrected error signal m1. At this time, only the predetermined-order frequency component of the signal m1 is to be controlled, while the engine vibration consisting of frequency components other than the frequency component is not to be controlled. The control signal s of the control calculator 25 is input to the speaker 11 and the speaker 11 vibrates. Between the vibration from the speaker 11 and the engine vibration detected by the microphone 18, the frequency components having opposite phases cancel each other out, and the frequency components having the same phase mutually strengthen each other. On the other hand, the frequency component of the engine vibration that is not controlled is not affected by the vibration of the speaker 11, and its amplitude value is maintained as it is. As a result, the engine vibration at the predetermined position in the vehicle interior 3 detected by the microphone 10 is
It is changed so as to be reduced, increased or maintained for each predetermined frequency component.

Specifically, the signal correction circuit 28 that receives the output of the engine rotation cycle measurement circuit 18 that detects the engine rotation speed, which is the vibration information of the vibration source in the vehicle, and measures the engine rotation cycle, causes the microphone to operate. Of the 10 error signals m0, an error signal m1 consisting of a predetermined frequency component, for example, a quadratic frequency component, in the engine rotation period measured by the measuring circuit 18 is pseudo-extracted and input to the control calculator 25. It Then, the control calculation unit 25 generates the control signal s for reducing the engine vibration including the frequency component. This control signal s
Are input to the speaker 11 and vibration is generated by the speaker 11, and the vibration and the frequency component of the engine vibration of the vehicle detected by the microphone 10 cancel each other out, so that the microphone 10 detects the vibration. Among the engine vibrations at the predetermined positions in the vehicle interior 3, the engine vibrations composed of the above frequency components are reduced.

Thus, the engine vibration of the frequency component of the predetermined order in the engine rotation cycle can be reduced, so that the engine vibration can be efficiently reduced according to the vibration characteristic. Further, by narrowing down the controlled object to a predetermined frequency component, the influence of disturbance can be reduced and the control performance can be improved.

(Second Embodiment) FIGS. 6 and 7 show a second embodiment of the present invention. The same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

The vehicle vibration reducing apparatus according to this embodiment reduces the engine vibration component of a predetermined order of the engine vibration detected at a predetermined position in the vehicle compartment. Instead of the signal extraction circuit 29a, a bandpass filter 29b in which the center frequency of the passband is variable
This bandpass filter 29b is used in the first embodiment described above.
It is arranged at the position of the low-pass filter 23 in the controller 16. The band pass filter 29b constitutes a signal correcting means, receives the output of the engine rotation cycle measuring circuit 18, and receives the output of the engine rotation cycle measuring circuit 18.
In order to extract the error signal m1 consisting of the frequency component of the error signal m0 by filtering the frequency component of the predetermined order corresponding to the cycle of the engine rotation measured in the above from the control signal m0 of the microphone 10. It is configured.

Here, the engine rotation period is set to T [se
c], where p is the order of the engine frequency to be reduced, the center frequency f0 of the bandpass filter 29b shown in FIG. 7 is set to be f0 = p / T [Hz].

Also according to this embodiment, the same operational effect as that of the first embodiment can be obtained.

(Third Embodiment) FIGS. 8 and 9 show a third embodiment of the present invention. The same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

The vibration reducing apparatus according to this embodiment excludes audio sound from the controlled object as a non-controlled object.
The signal correction circuit 29a shown in FIG. 8 receives the output of the vehicle-mounted audio device 9 as sound detection means, and receives the output of the microphone 1
0 of the error signal m0 from the audio device 9
The vibration signal m1 composed of frequency components other than the frequency component of the audio signal a as the sound signal is extracted. Then, the control calculation unit 25 is configured to generate a control signal s for reducing the vibration of the frequency components other than the frequency component of the audio signal a in the vibration detected by the microphone 10. .

The structure of the signal correction circuit 29a is shown in FIG. In the figure, 43 is an amplifier that amplifies the audio signal a from the vehicle-mounted audio device 9 with a set gain, and 44
Is a low-pass filter for filtering low-frequency components of the audio signal a amplified by the amplifier 43, and 45 is an analog-valued audio signal a filtered by the low-pass filter 44.
Is an A / D converter that converts the signal into a digital value signal a.
Further, 46 is a digital filter obtained by modeling the transfer characteristic between the speaker 11 and the microphone 10 based on the actual measurement result, and 47 is the digital filter 46.
Is an arithmetic unit for subtracting the output signal a'of the above from the error signal m0 input to the signal correction circuit 29a.

Here, the transfer function H of the digital filter 46 is a vector A (n) in which the instantaneous value of the vector H = [h0, h1, ..., hI] ^T audio signal a at time n is a (n). Is a vector A (n) = [a (n), a (n-1), ..., A (nI)], the time n output from the digital filter 46 is
The predicted value a ′ (n) at

[Equation 3] Becomes Therefore, by setting the instantaneous value e1 (n) of the error signal m1 input to the control calculator 25 to e1 (n) = e1 (n) -a '(n), the error input to the signal correction circuit 29a Of the instantaneous value e0 (n) of the signal m0, the audio signal a
It is possible to extract the vibration signal m1 having frequency components other than the predicted value a '(n) possessed by.

Therefore, in this embodiment, the signal correction means 2 to which the audio signal a of the vehicle audio equipment 9 is input.
In 9a, an error signal m1 having a frequency component other than the frequency component of the audio signal a is extracted from the error signal m0 from the microphone 10, and this error signal m1 is input to the control calculation section 25. In the control calculator 25, of the vibrations detected by the microphone 10, a control signal s for reducing vibrations having frequency components other than the frequency components of the audio signal a.
Is generated. This control signal s is input to the speaker 11 and vibration is generated by the speaker 11, and this vibration and the vibration composed of the above frequency component among the vibrations detected by the microphone 10 cancel each other out, and this causes the microphone 10 to vibrate. Among the vibrations at the predetermined position in the vehicle interior 3 detected by the above, vibrations having frequency components other than the frequency components of the audio signal a are reduced, and the audio sound by the audio signal a is caused by the vibration of the speaker 11. It is regenerated in the passenger compartment 3 without being reduced.

(Embodiment 4) FIGS. 10 to 12 show a third embodiment of the present invention. The same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

The vehicle vibration reducing apparatus according to this embodiment changes the engine vibration detected at a predetermined position in the passenger compartment 3 into a preset engine vibration for each engine speed. In FIG. 11 showing the signal extracting circuit 29a, 34 is a waveform memory.
Reference numeral 4 stores a target waveform for changing the engine vibration detected by the microphone 10 for each engine speed. Reference numeral 35 denotes an oscillator, which receives the output of the waveform memory 34 and outputs the target waveform signal of the waveform memory 34 in synchronization with the engine rotation with the ignition pulse t of the engine as a trigger. Reference numeral 36 denotes an arithmetic unit, which is an error signal m1 synthesized by subtracting the above waveform signal from the error signal m0 of the microphone 10.
Is input to the control calculation unit 25.

The target waveform is a target value set for each engine speed so that the engine sound quality detected in the passenger compartment 3 becomes a predetermined value, and one cycle of the target waveform at each speed. Minutes are stored in the waveform memory 34. Each target waveform is stored in the form of a plurality of amplitude values which are discretized at predetermined sampling periods as shown in FIG.

Therefore, in this embodiment, the error signal m1 is synthesized by superimposing the waveform signal x measured by the engine rotation cycle measuring circuit 18 according to the cycle of engine rotation on the error signal m0 from the microphone 10. It The error signal m1 thus synthesized is input to the control calculation unit 25, and the control calculation unit 25 changes the engine vibration detected by the microphone 10 into the engine vibration preset according to the cycle of engine rotation. A control signal s for generating is generated. At this time, only the predetermined-order frequency component of the signal m1 is to be controlled, while the engine vibration consisting of frequency components other than the frequency component is not to be controlled. The control signal s of the control calculator 25 is input to the speaker 11 and the speaker 11 vibrates. Vibration from this speaker 11 and microphone 1
With respect to the engine vibration detected by 8, the frequency components having mutually opposite phases cancel each other out, and the frequency components having the same phase mutually strengthen each other. On the other hand, the frequency component of the engine vibration that is not controlled is not affected by the vibration of the speaker 11, and its amplitude value is maintained as it is. As a result, the engine vibration at the predetermined position in the vehicle interior 3 detected by the microphone 10 has good engine sound quality that is predetermined for each engine speed.

Although the vehicle vibration is engine vibration in the above embodiment, other vibrations such as road surface vibration and exhaust vibration may be added or replaced.

Further, in the above embodiment, the vibration generating means is the speaker 11, but other than this, the vehicle vibration can be reduced by, for example, actively exciting the engine mount.

In the above embodiment, the error signal is corrected and the control signal is generated based on the LMS algorithm, but it may be based on other algorithms.

[0050]

As described above, according to the first aspect of the invention, the vibration signal detected at the predetermined position in the vehicle compartment is corrected and input to the control means. Therefore, the vibration reduction control is performed. While the target can be narrowed down to improve the control performance, it is possible to avoid the reduction of vibration other than the controlled target.

According to the second aspect of the present invention, the engine vibration of the frequency component of the predetermined order in the engine rotation cycle is reduced, so that the engine vibration can be efficiently reduced according to the vibration characteristic.

According to the third aspect of the invention, the frequency component other than the sound signal such as the audio signal of the on-vehicle audio device is extracted from the error signal and input to the control means. It is possible to avoid a situation in which the sound such as is reduced together with the vibration to be controlled.

According to the invention of claim 4, the correction waveform corresponding to the cycle of the engine rotation and the waveform of the error signal are combined so that the error signal has the target waveform. It is possible to obtain a preset engine sound effect.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of the present invention.

FIG. 2 is a schematic diagram showing an overall configuration of a vehicle vibration reduction device according to a first embodiment.

FIG. 3 is a block diagram showing a configuration of a controller.

FIG. 4 is a diagram showing a configuration of a control calculation unit using an LMS adaptive algorithm.

FIG. 5 is a diagram showing a configuration of a signal correction circuit using an adaptive algorithm of LMS.

FIG. 6 is a block diagram showing a configuration of a controller according to the second embodiment.

FIG. 7 is a diagram showing characteristics of a variable bandpass filter.

FIG. 8 is a block diagram illustrating a configuration of a controller according to the third exemplary embodiment.

FIG. 9 is a diagram showing a configuration of a signal correction circuit using an adaptive algorithm of LMS.

FIG. 10 is a block diagram illustrating a configuration of a controller according to a third exemplary embodiment.

FIG. 11 is a diagram showing a configuration of a signal correction circuit using an adaptive algorithm of LMS.

FIG. 12 is a diagram showing a sampled target waveform signal.

[Explanation of symbols]

 3 Car Room 4 Engine (Vibration Source) 9 In-Vehicle Audio Equipment (Sound Detection Means) 10 Microphone (Second Vibration Detection Means) 11 Speaker (Vibration Generation Means) 18 Engine Rotation Period Measurement Circuit (First Vibration Detection Means) 25 Control Calculation Part (control means) 29a signal correction circuit (signal correction means) 29b bandpass filter (signal correction means) m0 error signal (vibration signal) m1 error signal (predetermined signal) s control signal a audio signal (sound signal)

Claims (4)

[Claims] 1. A first vibration detecting means for detecting vibration information of a vibration source in a vehicle, a second vibration detecting means for detecting a vibration from the vibration source at a predetermined position in a vehicle compartment, and a second vibration detecting means. A signal correcting means for receiving the output of the means and correcting the vibration signal output from the second vibration detecting means into a predetermined signal, and receiving the outputs of the first vibration detecting means and the signal correcting means,
A control means for generating a control signal for changing the vibration detected by the second vibration detection means into a predetermined vibration, and a vibration generation means for generating vibration based on the output of the control means are provided. Characteristic vehicle vibration reduction device. 2. The vehicle vibration reduction device according to claim 1, wherein the first vibration detection means is configured to detect a cycle of engine rotation as vibration information of the engine in the vehicle, and the signal correction means is second Of the vibration signals from the vibration detecting means, a predetermined signal composed of frequency components of a predetermined order in the cycle of engine rotation detected by the first vibration detecting means is extracted, and the control means includes the second signal. A vibration reduction device for a vehicle, which is configured to generate a control signal for reducing engine vibration having a frequency component of a predetermined order among engine vibrations detected by the vibration detection means. 3. The vehicle vibration reduction device according to claim 1, further comprising a sound detection unit that detects information about a non-control target sound in the vehicle, and the signal correction unit includes a vibration signal from the second vibration detection unit. The control means is configured to extract a predetermined signal having a frequency component other than the frequency component included in the sound signal output from the sound detection means, and the control means may include, among the vibrations detected by the second vibration detection means, A vibration reduction device for a vehicle, which is configured to generate a control signal for reducing a vibration having a frequency component other than a frequency component included in the sound signal. 4. The vehicle vibration reduction device according to claim 1, wherein the first vibration detection means is configured to detect the cycle of engine rotation as the vibration information of the engine in the vehicle, and the signal correction means is the engine in advance. The vibration target waveform signal is set according to the rotation cycle, and the vibration target waveform corresponding to the engine rotation cycle detected by the first vibration detection means is included in the vibration signal from the second vibration detection means. Are configured to be combined with each other to synthesize a predetermined signal, and the control means changes the engine vibration detected by the second vibration detection means into an engine vibration preset according to the cycle of engine rotation. A vibration reduction device for a vehicle, which is configured to generate a control signal of