JP2007145326A - Active vibration noise control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an active vibration noise control device easy in diagnosing failure by preventing erroneous mounting while reducing a sort of active vibration noise control unit. <P>SOLUTION: This active vibration noise control device uses a loudspeaker of different audio devices and a loudspeaker for offsetting cabin inside vibration noise in common, and generates a reference sine wave signal of an audible frequency instead of a reference signal from a reference signal generating circuit 2A on the basis of specific operation different from ordinary operation of an indicating key switch 45 arranged in the respective audio devices, and diagnoses the existence of failure of a line reaching a loudspeaker including the loudspeaker 43 from a reproducing sound of the loudspeaker 43 by sending out the reference sine wave signal to an adding circuit 51 instead of a noise offsetting signal by switching changeover switch circuits 3-1 and 11, and diagnoses failure of a microphone 27 by supplying an output signal from the microphone 27 receiving the reproducing sound of the loudspeaker 43 based on the reference sine wave signal to a failure diagnosing circuit 9 via the changeover switch circuit 11. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an active vibration noise control apparatus that supplies an audio signal output from an audio unit and a canceling signal for canceling vehicle interior vibration noise to a common speaker unit and converts them into reproduced sound.

  There is an active vibration noise control device that supplies an audio signal output from an audio unit and a canceling signal for canceling vehicle interior vibration noise to a common speaker unit and converts them into reproduced sound (see, for example, Patent Document 1).

  An example of such an active vibration noise control apparatus includes an active vibration noise control unit 30-3, an audio unit 70, and a speaker unit 41, as shown in FIG.

  The audio unit 70 includes a sound source device 49 and an adder circuit 51, selects one audio sound source device from the sound source devices 49, and supplies an audio signal output from the selected audio sound source device to the adder circuit 51.

  The speaker unit 41 includes an amplifier circuit 42 and a speaker 43 provided in the passenger compartment. The amplifier circuit 42 amplifies the signal output from the adder circuit 51 and converts the output signal from the amplifier circuit 42 into reproduced sound by the speaker 43. To do.

  On the other hand, in the case of canceling out the vibration noise generated from the engine that is the vibration noise source, for example, the vehicle interior vibration noise based on the rotation of the four-cycle four-cylinder engine, it is caused by gas combustion that occurs every 1/2 rotation of the engine output shaft. Due to the torque fluctuation, the vibration generated from the engine as a base point is generated, which causes the vehicle interior vibration noise. Therefore, in the case of a four-cycle four-cylinder engine, a lot of vibration noise called a secondary rotation component having a frequency twice the engine output shaft rotational speed is generated.

  Based on the above, the active vibration noise control unit 30-3 generates a reference signal, which is a harmonic digital signal selected from the frequency of vibration noise generated from the vibration noise source, in the reference signal generation circuit 2, and generates a reference signal. The adaptive filter 4 generates a canceling signal for canceling the vehicle interior vibration noise based on the signal. On the other hand, the reference signal generation circuit 5-1 generates a reference signal by correcting the reference signal based on the correction data corresponding to the signal transfer characteristic, and based on the vehicle interior vibration noise by the microphone 27 provided in the vehicle interior. An error signal is detected, the filter coefficient of the adaptive filter 4 is calculated so as to minimize the error signal in the LMS algorithm calculation circuit 6 based on the reference signal and the error signal, and the filter coefficient is sequentially updated to adaptively The filter 4 generates an offset signal that minimizes the error signal.

  Here, the reference signal generation circuit 2, the adaptive filter 4, the reference signal generation circuit 5-1, and the LMS algorithm calculation circuit 6 are configured by a microcomputer 20-3.

  The cancellation signal generated by the adaptive fill 4 is added to the audio signal output from the sound source device 49 in the adding circuit 51, and the speaker unit 41 is driven by the added output signal so that the audio output from the audio unit 70 is output. The speaker unit 41 for generating reproduced sound based on the signal and the speaker unit for generating canceling sound based on the canceling signal output from the active vibration noise control unit 30-3 are shared.

  Here, the above signal transfer characteristic is a signal transfer characteristic from the adaptive filter 4 to the LMS algorithm arithmetic circuit 6, and the active vibration noise control unit 30-3 uses the correction data based on this signal transfer characteristic as a reference signal. Then, the canceling signal adapted to the signal transfer characteristic is generated from the adaptive filter 4.

JP-A-6-130971 (page 3, FIG. 1)

  However, in the measurement of the actual signal transfer characteristic in the active vibration noise control apparatus, as shown by the broken line in FIG. 9, the signal transfer characteristic measuring apparatus 100 comprising a Fourier transform apparatus is connected to the output end of the adaptive filter 4 and the LMS algorithm. A signal transfer characteristic between the error signal input terminals of the LMS algorithm arithmetic circuit 6 is measured by connecting between the error signal input terminals of the arithmetic circuit 6 and sandwiching the vehicle compartment from the output terminal of the adaptive filter 4.

  Accordingly, the signal transfer characteristics include the D / A converter 21 and the low-pass filter 22 connected from the output end of the adaptive filter 4 to the speaker 43, the amplifier circuit 42, and the microphone 27 to the LMS algorithm arithmetic circuit 6. The signal transfer characteristic by the amplifier circuit 23, the band pass filter 24, and the A / D converter 25 connected to is also included.

  However, in the case of an audio device mounted on a vehicle, an audio device having a normal configuration in which an audio unit is mounted in an instrument panel of the vehicle and an amplifier circuit and a speaker constituting the speaker unit are provided at predetermined positions in the vehicle compartment. (Also referred to as a standard audio device), the audio unit is provided in the instrument panel of the vehicle, and the equalizer, amplifier circuit, and speaker constituting the speaker unit are provided at predetermined positions in the vehicle interior. There are cases of audio devices based on premium specifications (also referred to as premium specification audio devices) configured to obtain high-power output playback audio signals. Each has a different configuration.

  As a result, the signal transfer characteristics differ as shown by the broken line and the solid line in FIGS. 10 (A) and 10 (B) based on the audio device mounted. 10A shows the gain characteristic in the signal transfer characteristic, FIG. 10B shows the phase characteristic in the signal transfer characteristic, the broken line shows the case of the standard specification audio device, and the solid line shows the case of the premium specification audio device. Illustrated.

  Therefore, there is a problem in that it is necessary to prepare a plurality of types of active vibration noise control units that share the speaker unit with the speaker unit of the audio device in order to adapt the signal transfer characteristics according to the speaker unit of the in-vehicle audio unit. there were.

  For this reason, there is a problem that the number of combinations of the in-vehicle audio unit and the active vibration and noise control unit increases, and erroneous mounting may occur.

  An object of the present invention is to provide an active vibration and noise control device that can reduce the types of active vibration and noise control units, prevent erroneous mounting, and facilitate failure diagnosis.

The active vibration noise control device according to claim 1 of the present invention comprises an audio device that outputs reproduced sound from a speaker, and an error signal detection means that detects vehicle interior vibration noise and outputs it as an error signal. In order to reduce noise, an active vibration noise control apparatus comprising an active vibration noise control unit that generates a cancellation signal so as to minimize the error signal and outputs the cancellation signal to the speaker.
The audio device includes an instruction switch operated by an operator, and a control signal generating unit that outputs a control signal based on a specific operation different from a normal operation of the instruction switch,
The active vibration noise control unit shifts to a failure diagnosis mode based on a control signal from the control signal generating means, and outputs a reference sine wave signal of an audible frequency instead of the cancellation signal when the failure diagnosis mode is shifted to. In addition, the presence / absence of a failure is determined based on the output signal frequency and the output signal voltage level of the error signal detection means, and when the failure is determined, the output of the reference sine wave signal is stopped.

  The active vibration noise control apparatus according to claim 1 of the present invention is the active vibration noise control apparatus according to claim 1, wherein the output of the reference sine wave signal is stopped during engine operation in the failure diagnosis mode. And

  According to the active vibration noise control device of the first aspect of the present invention, the audio device is provided with the instruction switch, and the control is output when the operator performs a specific operation different from the normal operation of the instruction switch. Based on the signal, it shifts to the failure diagnosis mode. By entering the fault diagnosis mode, the fault diagnosis of the active vibration noise control unit can be performed by operating the audio device in the manufacturing process or dealer, and there is a disconnection between the active vibration noise control unit and the speaker or error signal detection means This makes it easier to check for malfunctions. When the mode is shifted to the failure diagnosis mode, an audible frequency reference signal is output, and failure diagnosis can be performed based on the output signal frequency and the output voltage level of the error signal detection means. If no sound can be heard from the speaker even after switching to the failure diagnosis mode by operating the audio device, it can be determined that there is an abnormality in the active vibration noise control device or a disconnection between the active vibration noise control device and the speaker. If no sound is heard after a while, it is possible to determine that the error signal detecting means is abnormal or a disconnection between the active vibration noise control device and the error signal detecting means, and it is possible to identify the abnormal part by a simple method.

  According to the active vibration noise control apparatus of the second aspect of the present invention, if sound is heard from the speaker even when the engine is started in the failure diagnosis mode, the input unit of the active vibration noise control unit It is possible to determine that there is an abnormality or a disconnection, and it is possible to specify the abnormality location in more detail.

  Hereinafter, an active vibration noise control apparatus according to the present invention will be described with reference to embodiments. In this embodiment, an active vibration noise control unit, a standard audio device mounted on a vehicle, and a premium audio device will be described as an example.

  FIG. 1 and FIG. 2 are block diagrams showing the configuration of an active vibration noise control apparatus according to an embodiment of the present invention. FIG. 1 is an electrical diagram of an active vibration noise control unit and a standard specification audio apparatus electrically connected by a coupler. FIG. 2 shows a state in which the active vibration noise control unit and the premium audio device are electrically connected by a coupler.

  Here, in the example shown in FIG. 1, the active vibration noise control unit 30-1 is common to the case where the standard audio device 40 is mounted on the vehicle and the case where the premium audio device 60 is mounted on the vehicle. The active vibration noise control unit 30-1 and the standard audio device 40 are electrically connected by the coupler 28. Similarly, the premium audio device 60 is also active instead of the standard audio device 40. The mold vibration noise control unit 30-1 is electrically connected by a coupler 28.

  The standard audio device 40 includes an audio unit 44 and a speaker unit 41.

  The audio unit 44 includes an AM / FM tuner 49-1, which is an audio tone generator, a tone generator 49 comprising a cassette tape deck 49-2 and a CD deck 49-3, an equalizer 50 and an adder circuit 51, and a control circuit comprising a microcomputer. 46 and an instruction key switch 45 such as a power on / off switch, volume, sound source selection switch, channel selection switch, balance, mute switch, etc., which are instructed by the operator.

  The control circuit 46 receives the designation signal instructed from the instruction key switch 45 and selects the designated audio tone generator from the tone generator 49. The selected audio tone generator starts its operation, and the output audio signal is supplied to the equalizer 50, the frequency characteristic is compensated, supplied to the adder circuit 51, and added to the cancellation signal described later.

  The speaker unit 41 includes an amplifier circuit 42 and a speaker 43 provided in the passenger compartment. The added output signal output from the adder circuit 51 is amplified by the amplifier circuit 42, and the output signal from the amplifier circuit 42 is reproduced by the speaker 43. Is converted to

  Here, the audio unit 44 is mounted in an instrument panel of the vehicle, and the amplifier circuit 42 and the speaker 43 constituting the speaker unit 41 are provided at predetermined positions in the vehicle interior.

  The audio unit 44 includes a grounded-emitter transistor 47 that constitutes a control signal generating means for generating a control signal and a collector resistor 48A that constitutes a pull-up resistor having one end connected to a power supply, and is output from the control circuit 46. Is applied to the base of the transistor 47 to control on / off of the transistor 47.

  Normally, the control circuit 46 does not energize the base of the transistor 47, but controls the transistor 47 to be in an OFF state and outputs the high potential (H1) as a control signal to the active vibration noise control unit 30-1 through the coupler 28. When the control circuit 46 detects that a specific operation different from the normal operation of the sending and instruction key switch 45, for example, an operation of pressing the power on / off switch a predetermined number of times while pressing the mute switch, is performed. 46 causes a base current to flow through the transistor 47, controls the transistor 47 to be in an ON state, and sends an output of a low potential (ground potential L) through the coupler 28 to the active vibration noise control unit 30-1 as a control signal.

  The active vibration noise control unit 30-1 includes a waveform shaping circuit 1, a reference signal generation circuit 2, a cutoff switch circuit 3, an adaptive filter 4, a reference signal generation circuit 5, and an LMS algorithm calculation circuit 6 corresponding to a filter coefficient updating unit. A canceling signal generation circuit 20-1 (see FIG. 2) that outputs a canceling signal is provided. The canceling signal generating circuit 20-1 includes a switching control circuit 7 to which a control signal is input via a coupler 28.

  Further, the active vibration noise control unit 30-1 includes a D / A converter 21 that D / A converts the cancellation signal output from the cancellation signal generation circuit 20-1, and a D / A converted cancellation signal. A low-pass filter 22 sent to the speaker unit 41 via the coupler 28, an amplifier circuit 23 for amplifying the error signal detected by the microphone 27 corresponding to the error signal detecting means, and a band-pass filter 24 having the amplified output as an input. And an A / D converter 25 for sending the output of the bandpass filter 24 as an error signal to the cancellation signal generation circuit 20-1.

  As described above, the vibration noise generated from the engine that is the vibration noise source, for example, the case of canceling the vehicle interior vibration noise based on the rotation of the four-cycle four-cylinder engine, occurs every 1/2 rotation of the engine output shaft. Due to torque fluctuations caused by gas combustion, vibrations are generated with the engine as the starting point, causing vehicle interior vibration noise. Therefore, in the case of a four-cycle four-cylinder engine, as described above, a lot of vibration noise called a secondary rotation component having a frequency twice the engine output shaft rotational speed is generated.

  Therefore, the rotation of the engine output shaft is detected by a sensor, and the output signal from the sensor is waveform-shaped by the waveform shaping circuit 1, and the output signal from the waveform shaping circuit 1 is supplied to the reference signal generation circuit 2 for vibration noise. A reference signal which is a harmonic digital signal selected from the frequency of vibration noise generated from the source, for example, a reference signal of the rotational secondary component frequency is generated.

  The reference signal is supplied to the adaptive filter 4 via the cutoff switch circuit 3, and the reference signal is signal-processed in the adaptive filter 4 and a canceling signal for canceling the vehicle interior vibration noise is output from the adaptive filter 4. The cancellation signal is converted into an analog signal via the D / A converter 21 and the low-pass filter 22 and sent to the adder circuit 51.

  On the other hand, vehicle interior vibration noise is detected by a microphone 27 provided in the vehicle interior, and an error signal based on the vehicle interior vibration noise is amplified by an amplifier circuit 23, band-limited by a bandpass filter 24, and an A / D converter. In 25, an error signal converted into a digital signal is output.

  In the reference signal generation circuit 5, correction data CA based on the signal transfer characteristics of the speaker unit 41 in the standard audio device 40 and correction data CB based on the signal transfer characteristics of the speaker unit 61 in the premium audio device 60 are stored in advance. Then, one correction data CA or correction data CB is selectively read according to the audio device 40 or 60, and a reference signal is generated by performing correction processing on the reference signal based on the read correction data CA or CB. Is done.

  The LMS algorithm calculation circuit 6 performs LMS algorithm calculation based on the reference signal and the error signal, and sequentially updates the filter coefficient of the adaptive filter 4 so as to minimize the error signal based on the calculation result. 4 is output to the adder circuit 51, added to the audio signal output from the equalizer 50, amplified by the amplifier circuit 42 and converted into reproduced sound by the speaker 43, and the vehicle interior vibration noise is canceled out. The

  Here, in the case of the audio device 40 of the standard specification, in addition to the signal transfer characteristic from the speaker unit 41 to the microphone 27, the signal transfer characteristic is from the output end of the adaptive filter 4 to the input end of the LMS algorithm arithmetic circuit 6. The signal transfer characteristics of the connected D / A converter 21, low-pass filter 22, adder circuit 51, amplifier circuit 42, speaker 43, microphone 27, amplifier circuit 23, band-pass filter 24, and A / D converter 25 are also included. . The same applies to the premium audio device 60.

  Therefore, the correction data CA is correction data based on the signal transfer characteristics in the case of the standard specification audio apparatus 40, and the correction data CB is correction data based on the signal transfer characteristics in the case of the premium specification audio apparatus 60.

  Next, when the premium audio device 60 is mounted on a vehicle, the active vibration noise control device includes an active vibration noise control unit 30-1 and a premium audio device 60 as shown in FIG. The active vibration noise control unit 30-1 has the same configuration as that shown in FIG.

  The audio device 60 of the premium specification includes an audio unit 62 and a speaker unit 61. The audio unit 62 includes an instruction key switch 45, a control circuit 46, a sound source device 49, and a coupler 28. The output audio signal from the audio sound source device is supplied to the adding circuit 51 and added to the canceling signal in the adding circuit 51.

  The speaker unit 61 includes an equalizer 50-1, an amplifier circuit 42-1, and a speaker 43-1. The added output signal output from the adder circuit 51 is frequency-compensated in the equalizer 50-1, and amplified in the amplifier circuit 42-1. In addition, it is converted into a reproduced sound by the speaker 43-1.

  Here, in the premium-spec audio device 60, the equalizer 50-1 is a high-function equalizer with a large adjustment frequency point and a wide adjustment range, compared with the standard-spec audio device 40, and the amplifier circuit 42-1 has an output. A high-performance amplifier circuit with a wide bandwidth, and the speaker 43-1 is a high-performance speaker with a wide reproduction bandwidth.

  In the case of the premium-spec audio device 60, the control circuit 46 includes a transistor 47 whose control signal generating means for generating a control signal is grounded, and a collector resistor 48B whose one end is connected to a power source. An output signal is applied to the base of the transistor 47 to control on / off of the transistor 47.

  Normally, the control circuit 46 does not energize the base of the transistor 47, but controls the transistor 47 to be in an OFF state and couples the output of the high potential (H2 <H1) as a control signal to the active vibration noise control unit 30-1. 28, when the control circuit 46 detects that a specific operation different from the normal operation of the instruction key switch 45, for example, an operation of pressing the power on / off switch a predetermined number of times while pressing the mute switch is performed. The control circuit 46 causes a base current to flow through the transistor 47, controls the transistor 47 to be in an ON state, and sends a low potential (ground potential L) output as a control signal to the active vibration noise control unit 30-1 through the coupler 28.

  The active vibration noise control unit 30-1 and the audio device 40 or 60 are electrically connected by two signal lines via the coupler 28, and one signal line A is connected to the active vibration noise control unit 30. -1 is transmitted to the audio device 40 or 60. The other signal line B transmits a control signal from the audio device 40 or 60 to the active vibration noise control unit 30-1.

  When the active vibration noise control unit 30-1 is electrically connected to the audio device 40 or 60 via the coupler 28, the voltage corresponding to the resistance values of the collector resistors 48A and 48B is changed to the active vibration noise control unit 30-1. Is input to the cancellation signal generation circuit 20-1. More specifically, in the case of the standard specification audio device 40, a voltage of 5 V (H 1) is input to the switching control circuit 7, and in the case of the premium specification audio device 60, a voltage of 2.5 V (H 2) is input to the switching control circuit 7. Will be.

  The switching control circuit 7 determines the specifications of the mounted audio device based on the voltage value of the control signal input from the audio device.

  Based on this determination, when it is determined that the standard audio device 40 is mounted, the voltage value of the control signal is high potential (H1), and the cutoff switch is controlled under the control of the switching control circuit 7. The circuit 3 is switched to the contact position (on position) shown in FIG. 2, the correction data CA is read, and a reference signal in which a correction process is performed on the reference signal is generated based on the read correction data CA, Based on the reference signal and the error signal, the filter coefficient of the adaptive filter 4 is updated to the filter coefficient that minimizes the error signal, and a cancellation signal is generated to cancel the vehicle interior vibration noise.

  Based on the above determination, when it is determined that the premium audio device 60 is mounted, the voltage value of the control signal is high potential (H2), and is controlled under the control of the switching control circuit 7. The switch circuit 3 is switched to the contact position (ON position) shown in FIG. 2, the correction data CB is read out, and a reference signal in which correction processing is performed on the reference signal is generated based on the read out correction data CB. In the same manner as when the standard audio device 60 is mounted, the vehicle interior vibration noise is canceled.

  The operation of the active vibration noise control apparatus according to the above-described embodiment of the present invention will be described with reference to FIG.

  In the active vibration noise control apparatus according to the embodiment of the present invention, when the instruction key switch 45 is normally operated, the transistor 47 is in the OFF state, and the collector potential of the transistor 47 is high, that is, The voltage value of the control signal becomes a high potential (a high potential H1 when the standard audio device 40 is connected, and a high potential H2 when the premium audio device 60 is connected). When receiving a high potential (H1, H2) control signal, the active vibration noise control unit 30-1 performs a vibration noise control operation.

  In the active vibration noise control apparatus according to the embodiment of the present invention, when the transistor 47 is turned on by an operation of the instruction key switch 45 that is not normally performed, the collector potential of the transistor 47 is the ground potential, that is, the voltage of the control signal. Becomes the ground potential (L), and when the control signal of the ground potential (L) is received, the cutoff switch circuit 3 is switched from the position of FIG. 2 to the off position, and the active vibration noise control unit 30-1 vibrates. The noise control operation can be substantially stopped.

  Therefore, in the active vibration noise control apparatus according to the embodiment of the present invention, the voltage value of the control signal can be set to the ground potential (L) by switching the transistor 47 to the on state by operating the instruction key switch 45. When the ground potential control signal is input to the switching control circuit 7, the operation of the active vibration noise control unit 30-1 is stopped.

  As a result, the operator operates the instruction key switch 45 by a dealer or the like to determine the active vibration noise control based on the degree of noise reduction during normal operation of the active vibration noise control device and when the operation of the active vibration noise control device is stopped. The presence / absence of a failure in the unit 30-1 can be easily determined.

  When the control circuit 46 of the audio devices 40 and 60 detects an operation different from the normal operation of the instruction key switch 45 during the output of the base current to the transistor 47 (the same operation as described above is possible), Since the output is stopped, the active vibration noise control unit 30-1 resumes the generation of the cancellation signal according to the control signal of the high potential (H1, H2) (returns to the normal operation).

  Next, an active vibration noise control device according to the present invention will be described with reference to another embodiment.

  FIG. 4 is a block diagram showing a configuration of an active vibration noise control apparatus according to another embodiment of the present invention, in which an active vibration noise control unit and a standard audio apparatus are electrically connected via a coupler. FIG. 5 shows a state in which a premium audio device is electrically connected to the active vibration noise control unit instead of the standard audio device.

  In the active vibration noise control apparatus according to another embodiment of the present invention, the standard audio apparatus 40 and the premium audio apparatus 60 are the same as those of the active vibration noise control apparatus according to the embodiment of the present invention. In order to avoid duplication, detailed description thereof is omitted.

  The active vibration noise control unit 30-2 in the active vibration noise control apparatus according to another embodiment of the present invention includes a waveform shaping circuit 1, a reference signal generation circuit 2A, a changeover switch circuit 3-1, an adaptive filter 4, It is composed of a reference signal generation circuit 5, an LMS algorithm arithmetic circuit 6, a switching control circuit 7 to which a control signal is input via a coupler 28, a failure diagnosis circuit 9, a cutoff switch circuit 10, a switching switch circuit 11, and the like, and provides a canceling signal. A canceling signal generation circuit 20-2 comprising a microcomputer for outputting, a D / A converter 21 for D / A converting the canceling signal, and sending the D / A converted canceling signal to the speaker unit 41 via the coupler 28. A low-pass filter 22 for performing amplification, an amplification circuit 23 for amplifying an error signal detected by a microphone 27 corresponding to the error signal detection means, and the amplification A band pass filter 24 which receives the force, and an A / D converter 25 for sending an error signal output of the band-pass filter 24 to the canceling signal producing circuit 20-1.

  As is clear from the above, the active vibration noise control unit 30-2 is provided with the failure diagnosis circuit 9, the cutoff switch circuit 10, and the changeover switch circuit 11 in the active vibration noise control unit 30-1, A changeover switch circuit 3-1 is provided in place of the circuit 3, and the cancellation signal is generated in the same manner as the active vibration noise control unit 30-1.

  The reference signal output from the reference signal generation circuit 2A is selectively sent to the adaptive filter 4 and the cutoff switch circuit 10 via the changeover switch circuit 3-1, and the cancellation signal output from the adaptive filter 4 and the failure diagnosis circuit 9 are transmitted. One of the reference signal output via the cutoff switch circuit 10 controlled by the cutoff is output to the D / A converter 21, and the error signal output from the A / D converter 25 passes through the changeover switch circuit 11. Thus, the LMS algorithm arithmetic circuit 6 or the failure diagnosis circuit 9 is selectively led to switch the changeover switch circuits 3-1 and 11 with the changeover control signal of the changeover control circuit 7.

  When the standard audio device 40 or the premium audio device 60 is electrically connected to the active vibration noise control unit 30-2 through the coupler 28, the switching control circuit 7 that determines the voltage value of the control signal. Under the control, the changeover switch circuits 3-1 and 11 are controlled to the changeover positions shown in FIGS.

  When the standard audio device 40 is electrically connected to the active vibration noise control unit 30-2 through the coupler 28, the reference signal generation circuit 5 reads the correction data CA, and the premium audio device When 60 is electrically connected through the coupler 28, the reference signal generation circuit 5 reads the correction data CB, and the adaptive filter 4 performs the same as in the case of the active vibration noise control unit 30-1. A canceling signal is generated to cancel the vehicle interior vibration noise.

  That is, the type of the audio devices 40 and 60 mounted on the vehicle is instructed to the switching control circuit 7 by the control signal from the audio units 44 and 62.

  As a result, the cancellation signal corresponding to the instructed audio device 40 (60) is automatically generated by the active vibration noise control unit 30-2, respectively, and the vehicle interior vibration noise is canceled. Therefore, the same active vibration noise control unit 30-2 is sufficient for each of the audio devices 40 (60). Furthermore, it is not necessary to manually adjust the active vibration noise control unit 30-2 when assembling the vehicle according to the type of the audio device 40 (60) that is mounted.

  Further, when the control circuit 46 detects a specific operation different from the normal operation of the instruction key switch 45, for example, pressing the power on / off switch a predetermined number of times while pressing the mute switch, the switching control circuit 7 is connected to the ground. A control signal of potential (L) is input from the audio device 40 (60). The active vibration noise control unit 30-2 receives the control signal of the ground potential (L), shifts to the failure diagnosis mode, and controls the reference noise signal generation circuit 2A from the vibration noise source under the control of the switching control circuit 7. Instead of the harmonic reference signal selected from the frequency of the generated vibration noise, a reference sine wave signal having an audible frequency irrelevant to the vibration noise is generated, and the changeover switch circuits 3-1 and 11 are shown in FIGS. The reference position sine wave signal having an audible frequency is output to the adder circuit 51 in place of the canceling signal.

  Therefore, in this case, the vehicle interior vibration noise is not canceled, and the speaker 43 (43-1) is driven by the audible frequency reference sine wave signal output from the reference signal generation circuit 2A to generate a specific audible sound. To do. By confirming the generation of the specific audible sound, it is understood that the line including the speaker 43 (43-1) and extending from the changeover switch circuit 3-1 to the speaker 43 (43-1) is normal. When no specific audible sound is generated from the speaker 43 (43-1), the speaker 43 (43-1) is disconnected or the line from the changeover switch circuit 3-1 to the speaker 43 (43-1) is disconnected. It turns out that it is abnormal. As described above, the operator of the instruction key switch 45 can determine whether the line extending from the speaker 43 (43-1) and the changeover switch circuit 3-1 to the speaker 43 (43-1) is normal or abnormal.

  The output signal from the microphone 27 that has detected the reproduced sound generated by receiving the audible reference sine wave signal is supplied to the failure diagnosis circuit 9 via the changeover switch circuit 11 so that the failure diagnosis of the microphone 27 can be performed. That is, when a reference sine wave signal having an audible frequency is received and the output signal from the microphone 27 has the same frequency as the reference sine wave signal and the voltage level is inverted between a positive level and a negative level, the failure diagnosis circuit 9 causes the microphone 27 to Is diagnosed as normal. In addition, when only a positive level or a negative level is generated from the microphone 27 for a predetermined time (for example, 5 seconds) in spite of receiving a reproduction sound generated by inputting a reference sine wave signal of an audible frequency, a failure diagnosis is performed. The circuit 27 diagnoses that the microphone 27 is abnormal.

  When the failure diagnosis circuit 9 diagnoses that the microphone 27 is abnormal, the failure diagnosis circuit 9 stops the generation of the specific audible sound by switching the cutoff switch circuit 10 from the position of FIGS. 4 and 5 to the off position. Thereby, the operator of the instruction key switch 45 can determine that the microphone 27 is abnormal because the specific audible sound is interrupted after a predetermined time has elapsed.

  The operation of the active vibration noise control apparatus described above will be described with reference to FIGS.

  As shown in FIG. 6, when the switching control circuit 7 receives a control signal of a high potential (H1), the mounted audio device is determined to be the standard audio device 40 by the switching control circuit 7 and the correction data. When CA is read and a high-potential (H2) control signal is received, the mounted audio device is determined to be the premium audio device 60 by the switching control circuit 7 and the correction data CB is read. When the low potential (L) control signal is received, the active vibration noise control operation for generating the canceling signal is stopped and the failure diagnosis mode is entered.

  This will be described based on the flowcharts of FIGS. 7 and 8. When the active vibration and noise control device is started, initial settings are made (step S1), an idle period is waited (step S2), and an active vibration and noise control routine is executed. Is executed (step S3). When the execution of step S3 is started, the level of the control signal input to the switching control circuit 7 is checked (step S31). If it is determined in the level check of the control signal that the level is the high potential level H1 (= 5V), the correction data CA is selected (step S33). If it is determined in the control signal level check that the level is the high potential level H2 (= 2.5 V), the correction data CB is selected (step S32).

  Following the execution of step S3, the control signal level is checked (step S5), and if it is determined that it is other than the ground potential (= L), it is checked whether the vehicle speed is greater than 0 km / h, that is, within the control range. Is checked (step S6). If it is determined in step S6 that the vehicle speed is greater than 0 km / h (running), that is, it is determined that the vehicle speed is within the control range, the active vibration noise control unit 30-2 is operated to perform active vibration noise control. Processing (ANC processing) is performed (step S7), an offset signal is output (step S9), and the processing is repeated from step S5.

  If it is determined in step S6 that the vehicle speed is 0 km / h (stopped), that is, it is determined that the vehicle is out of the control range, the cancellation signal (output signal) is set to 0 (step S8), and the cancellation signal of 0 is set. Is output (step S9) and is repeatedly executed from step S5. This is because step S8 is executed when the vehicle is stopped, and it is not particularly necessary to cancel the vehicle interior vibration noise.

  If it is determined in step S5 that the level of the control signal is the ground potential (L), a failure diagnosis process is executed (step S10), and the process is executed from step S11.

  As shown in FIG. 8, when the execution of the failure diagnosis process is started, it is checked whether or not the engine is stopped (step S11). When it is determined in step S11 that the engine is stopped, an audio frequency reference sine wave signal is output from the reference signal generation circuit 2A (step S12), and then a failure diagnosis of the microphone 27 is performed (step S12). S13).

  In the failure diagnosis of the microphone 27 in step S13, the failure diagnosis of the microphone 27 is performed based on the output signal of the microphone 27 as described above.

  Following step S13, it is checked whether the microphone 27 is normal or abnormal based on the failure diagnosis result of the microphone 27 (step S14), and if it is determined to be normal, the process returns.

  When it is determined in step S14 that the microphone 27 is not normal, the cutoff switch circuit 10 is turned off to stop the output of the audible frequency reference sine wave signal (step S15), and the engine is stopped in step S11. If it is determined that it has not been made, the output of the audible frequency reference sine wave signal is stopped (step S15), and then the process returns.

  Such a failure diagnosis process is easily executed by operating the instruction key switch 45 of the audio devices 40 and 60, so that, for example, the operator shifts to the failure diagnosis mode by a dealer or the like, and a reference sine wave of an audible frequency is obtained. If a specific audible sound based on the signal is not heard at all, it can be recognized that the signal line A is broken or the output system part of the active vibration noise control unit 30-2 is broken, and it is possible after a predetermined period (5 seconds). If the listening sound is interrupted, it can be recognized that the microphone 27 is broken, and if an audible sound is heard while the engine is operating, the input system of the active vibration noise control unit 30-2 to which the engine pulse is input. It can be recognized as a failure of the part.

  In addition, since it is possible to determine the presence or absence of a failure by outputting an audible sound, there is no need for a separate failure diagnosis output means such as a warning light, and the cost can be reduced.

  In the embodiment of the present invention, the specification of the audio device to be connected is determined by making the control signal different using a pull-up resistor. However, by operating the instruction key switch 45, a predetermined voltage is applied from the control circuit 46. The value may be output to the active vibration noise control unit 30-2.

  As described above, according to the active vibration noise control device of the present invention, the audio device mounted on the vehicle can be discriminated by the active vibration noise control unit according to the instruction of the control signal. A cancellation signal corresponding to the speaker unit can be generated in the active vibration noise control unit so that the vehicle interior vibration noise can be canceled, and different audio devices can be handled by one active vibration noise control unit. Can do. Further, there is an effect that failure diagnosis of the speaker and the error signal detection means can be easily performed.

It is a block diagram which shows the structure of the active vibration noise control apparatus concerning embodiment of this invention, and is a figure which shows the case where the audio apparatus of a standard specification is mounted. It is a block diagram which shows the structure of the active vibration noise control apparatus concerning embodiment of this invention, and is a figure which shows the case where the audio apparatus of premium specification is mounted. It is a figure with which it uses for action description of the active vibration noise control apparatus concerning embodiment of this invention. It is a block diagram which shows the structure of the active vibration noise control apparatus concerning other embodiment of this invention, and is a figure which shows the case where the audio apparatus of a standard specification is mounted. It is a block diagram which shows the structure of the active vibration noise control apparatus concerning other embodiment of this invention, and is a figure which shows the case where the audio apparatus of premium specification is mounted. It is explanatory drawing which shows the state of the control signal in the active vibration noise control apparatus concerning other embodiment of this invention, selection of an audio apparatus, and correction data. It is a flowchart with which it uses for action description of the active vibration noise control apparatus concerning other embodiment of this invention. It is a flowchart with which it uses for action description of the active vibration noise control apparatus concerning other embodiment of this invention. It is a block diagram which shows the structure of the conventional active vibration noise control apparatus. FIG. 10A is a signal transfer characteristic diagram in the active vibration noise control apparatus, FIG. 10A shows gain characteristics, and FIG. 10B shows phase characteristics.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Waveform shaping circuit 2, 2A ... Reference signal generation circuit 3, 10 ... Cutoff switch circuit 3-1, 11 ... Changeover switch circuit 4 ... Adaptive filter 5 ... Reference signal generation circuit 6 ... LMS algorithm arithmetic circuit 7 ... Switching control circuit DESCRIPTION OF SYMBOLS 9 ... Fault diagnosis circuit 20-1, 20-2 ... Cancellation signal generation circuit 27 ... Microphone 28 ... Coupler 30-1, 30-2 ... Active type vibration noise control unit 40 ... Standard specification audio apparatus 43, 43-1 ... Speaker 41, 61 ... Speaker unit 44, 62 ... Audio unit 45 ... Instruction key switch 46 ... Control circuit 47 ... Transistor 48A, 48B ... Collector resistor 49 ... Sound source device 50, 50-1 ... Equalizer 51 ... Adder circuit 60 ... Premium specification Audio equipment

Claims (2)

An audio device that outputs reproduced sound from a speaker and an error signal detection means that detects vehicle interior vibration noise and outputs it as an error signal. In order to reduce vehicle interior vibration noise, an offset signal is used to minimize the error signal. An active vibration noise control device comprising an active vibration noise control unit that generates and outputs to the speaker;
The audio device includes an instruction switch operated by an operator, and a control signal generating unit that outputs a control signal based on a specific operation different from a normal operation of the instruction switch,
The active vibration noise control unit shifts to a failure diagnosis mode based on a control signal from the control signal generating means, and outputs a reference sine wave signal of an audible frequency instead of the cancellation signal when the failure diagnosis mode is shifted to. And determining whether or not there is a failure based on the output signal frequency and the output signal voltage level of the error signal detecting means, and stopping the output of the reference sine wave signal when it is determined that there is a failure. Control device.   2. The active vibration noise control apparatus according to claim 1, wherein the output of the reference sine wave signal is stopped while the engine is operating in the failure diagnosis mode.

Images