DE4442233A1 - Engine noise compensation and control system in car - Google Patents

Abstract

A noise compensation system in a car has a detector to evaluate the relevant information, a generator for a corresponding control signal and a control noise generator sited in the noise propagation path which is activated by the control signal to interfere with the propagated noise. The noise generator is in the engine bay near the firewall or near the radiator grill. The detector measures the engine speed and engine load. The control signal is at a frequency corresponding to the engine speed and load, while a memory unit supplies a corresponding phase and amplitude. There may be several different noise generators.

Description

The present invention relates to a Ge noise control system or on a noise compensation system in which a noise generated by an engine overlaid with a control tone of an actuator is to compensate for the noise of the engine or off weaken or to convert the sound into a tone with a ge to convert the desired characteristic, with noise au are processed inside and inside a vehicle, to create the desired characteristic.

Conventional noise control systems in this area are classified into a type in which an actuator Positioned near a noise source and another type in which an operation link not near a noise source but in the Proximity of such a position to obtain a tax effect is arranged to control a sound to add.

The difficulty arises with the former type speed that when using the object in a drive stuff that has many sources of noise, many actuations be arranged for many sources of noise must, which creates the difficulty, a suitable th place to attach the actuators. The latter type has the difficulty that since the noise and the control tone differ Chen ways are transmitted, the area in which the Tax effect is carried out appropriately, is narrow and in another area of the control tone to increase the Noise leads.

The object of the invention is a noise control system system to create the appropriate tax effect  over a wide area using a small one Number of actuators is reached.

The task is solved by a noise control system in which an actuator within egg ner noise source side or at a noise source end a sound propagation path is arranged by which the noise emitted by the vehicle from the Transfer the vehicle out or into the vehicle is a controller, which is attached to the actuator is closed to generate a control waveform signal of the control tone for controlling the of the operation member to be emitted noise and which Sensors connected to the controller, data capture that are necessary for the controller, the control world lenform signal to generate, for example information be regarding engine speed and engine load.

In accordance with the noise control system of the present invention is the actuator in Ge noise source side or at a noise source end of the Noise propagation path arranged through which a noise emitted by the vehicle from the vehicle is transmitted out or into the vehicle the controller to generate the control waveform signal of the control tone for controlling the of the operation link emitted noise, and detect the sensors Data that are necessary for the controller to generate the To cause control waveform signal. As a result, you can the sounds that come from many noise sources eventually run out of engine, through actuators corresponding to a small number of noise propagators paths are controlled, and the noise and the Control tone of each actuator can be controlled by the same Transmission path out of the vehicle or into the vehicle be emitted into it, reducing the noise and the control tone reproduce in the same way and thus  realizes the noise control over a large area can be.

Further details, aspects and advantages of this ing invention emerge from the following Be description with reference to the drawing.

Fig. 1 shows a diagram for briefly explaining the concept of the present invention;

Fig. 2 shows a diagram of an arrangement of a Ge noise control system in accordance with a first embodiment of the present invention for controlling noise in the interior of a vehicle;

Fig. 3 shows a block diagram of an arrangement of a controller 4 of Fig. 2;

Fig. 4 is a diagram showing a map information stored in a memory 47 of Fig. 3 (phase controls and amplitude controls);

Fig. 5 shows a flowchart for setting a Pha sensteuerung and an amplitude control on a phase control circuit 44 and an amplitude controller TIC 45 under control of a CPU 46;

Fig. 6 is a diagram showing an arrangement of a Ge räuschsteuerungssystems in accordance with a two-th embodiment of the present invention for controlling a sound (left side), which starts from outside of a vehicle;

Fig. 7 is a diagram showing an arrangement of a Ge räuschsteuerungssystems in accordance with a drit th embodiment of the present invention for controlling a sound (front side), which starts from outside of a vehicle;

Fig. 8 is a diagram showing a mounting arrangement of a 2-point noise control system in accordance with a fourth embodiment of the present OF INVENTION dung for controlling a vehicle sound;

Fig. 9 shows a block diagram of a controller 83 of Fig. 8;

Fig. 10 illustrates the map information (phase controls and amplitude controls) stored in a memory 838 of Fig. 9;

Fig. 11 is a flowchart for explaining an Ver driving, as the phase controllers and Amplitudensteuerun gen to the phase control circuits A and B (834 and 836) and the amplitude control circuits A and B (835 and 837) are to be determined under control of a CPU 839;

Fig. 12 is a diagram for explaining a system for determining the map information stored in the memory 838 of Fig. 9;

Fig. 13 shows a flow chart for explaining an algorithm for determining the allocation Algo or card informa tion of the 2-point noise control system of the fourth From guide die;

FIG. 14 is a diagram showing a mounting arrangement of a 3-point noise control system in accordance with a fifth embodiment of the present OF INVENTION dung for controlling the vehicle noise;

Fig. 15 shows a block diagram of a controller 83 of Fig. 14;

Fig. 16 is a diagram for explaining a system for determining the map information within the memory 838 of Fig. 15;

Fig. 17 shows a flow chart for explaining an algo rithm tion for determining the allocation and map Informa in the 3-point noise control system of the fifth embodiment;

Fig. 18 is a schematic diagram showing a matching noise measurement system for generating a map or map for use in a noise control system in over illustrating a sixth embodiment of the constricting vorlie invention; and

Fig. 19 is a flowchart showing an algorithm for determining the map information in the noise control system of the sixth embodiment.

Referring to FIG. 1, the concept of the present invention is illustrated briefly. In consideration of a sound propagation path 71 , through which noises emanating from many sources of sound generation including an engine of the vehicle are mainly transmitted to the interior of the vehicle via an instrument panel part, a single actuator 6 is provided in the interior of the vehicle for the purpose of noise reduction Located near the dash panel within an engine compartment and is operated in a controlled manner to provide a preferably controlled effect on noise over a wide area of the vehicle interior. Since the noise and a control sound are transmitted to the inside of the vehicle through the same path as mentioned above, a stable effect can be obtained over a wide range even if the condition inside the vehicle changes, for example, when there is a passenger inside or is missing. A change in the number of passengers to be carried in a vehicle can thus be managed.

Furthermore, the invention may even apply to that of outside noise from the vehicle (on this According to this, noise is sometimes referred to as vehicle emissions referred to a favorable tax effect on that show noise coming from outside the vehicle, which from the vicinity of the dashboard part within the Mo comes from the goal area and then through openings in the back progresses from wheels or tires. Control procedure of vehicle exterior noise include the tax an air inlet port, a cooling grille, from Openings near the wheel and / or an outlet port in the noise transmission path. That is how it is Noise control system of the present invention fen so that actuators in the noise source lens sides or at the noise source ends of larger ones Transmission paths of different parts of the driving stuff including the vehicles broadcast on the machine mission external noise and internal noise are arranged. Thus, sounds that are of different sounds well including the vehicle engine corresponding actuators are controlled, which in a small number of sound transmission paths are classified and with regard to vehicle emissions outside and inside noise as well as outside or inside noise, and the control tones of the actuators become radiated through the same transmission path, so that both the sounds as well as the control tones are the same can reproduce and thus the tax effect over a large area can be achieved.  

There will be a detailed explanation regarding one first embodiment of the present invention under Be given access to the associated figures.

FIG. 2 shows a diagram of an arrangement of a noise control system in accordance with a first embodiment of the present invention for controlling noise inside a vehicle. An engine which is electronically controlled is usually arranged to provide an engine speed sensor 1 and an engine load sensor 2 such as an intake pack pressure sensor, it is an air flow meter or a throttle position sensor as in Fig. 2 explains hen hen to supply the respective output signals of the above sensors 1 and 2 to an engine control unit 3 . The engine control unit 3 is connected to a controller 4 via a signal line through which the notor rotation information and the engine load information are transmitted.

Fig. 3 shows a block diagram of the controller 4 of Fig. 2. Accordingly, in the controller 4, a motor rotation pulse signal is applied to a shaping circuit 41 , which is sequential with a multiplication circuit 42 , a low-pass filter 43 , a phase control circuit 44 and an amplitude controller TIC 45 is connected in this order so that the 45 optionally a control output on plitudensteuerungsschaltung waveform signal. In this case, a phase control for the phase control circuit 44 and an amplitude control for the amplitude control circuit 45 are determined by the CPU 46 , which reads out map information from a memory 47 based on the engine revolution signal and an engine load signal, which is from the engine revolution sensor 1 or the engine load sensor 2 have been received. Furthermore, the controller 4 is connected via a signal line to the actuator 6 and further through another signal line to an amplifier 5 . In the illustrated example, the actuator 6 in the noise source side or at the noise source end of the noise propagation path 71 is from a noise source inside the engine room into the vehicle interior, that is, near (inside the engine room) 70 of a dashboard 80 which is an engine room 7 and the inside of one Vehicle 8 defined, attached.

FIG. 4 illustrates map information stored in the memory 47 of FIG. 3. The present embodiment intends to add a secondary component (a primary component of the combustion or explosion) to the engine revolution of a 4-cylinder engine reduce, which creates the problem of a muffled sound inside the vehicle. First, the sound pressure level and the phase of the noise (secondary component of the engine revolution) within the engine compartment nearby (within the engine compartment) 70 of the dashboard 80 which separates the engine compartment 7 and the vehicle interior 8 from each other are caused by the engine revolution speed and the Engine load is determined so that the phase control and the amplitude control of a control tone for reducing such noise are previously stored in the memory 47 as a map information which parameters of the engine revolution speed and the engine load have, as shown in Fig. 4.

An explanation will be given of the operation of the controller 4 of the noise control system having such an arrangement as mentioned above. Accordingly, FIG. 3 is subjected to the motor rotation pulse signal to a shaping circuit 41 with respect to a noise removal operation and thereafter, the multiplier 42 with respect to a Multiplizieropera tion to be converted into a pulse signal to whoever indicating the engine revolution secondary component. The pulse signal of the revolution secondary component is then subjected to a low-pass filter 43 with respect to a harmonic component removal operation to be converted into a sinusoidal wave signal indicative of an engine revolution secondary component. The sinusoidal wave signal of the rotation secondary component is further subjected to the phase control circuit 44 and the amplitude control circuit 45 with respect to phase and amplitude control operations, respectively, to be converted into the control waveform signal mentioned above.

FIG. 5 shows a flow chart for determining the phase and amplitude controls on the phase control circuit 44 and the amplitude control circuit 45, respectively, under the control of the CPU 46 of FIG. 3.

As shown in the drawing, the engine rotation speed information and the engine load information are input in a step S400. In step S401, the presence or absence of a change in the rotation speed and the load is judged. In a step S402, the assignment information is read out in accordance with the changed rotational speed and load. In a step S403, the phase control read out is determined on the phase control circuit 44 . In a step S404, the read-out amplitude control is determined on the amplitude control circuit. In step S405, the aforementioned process is repeated until control is ended.

According to Fig. 2, out of the controller rising control waveform signal is supplied via the amplifier 5 to the loading tätigungsglied 6 transmits, to which the signal is converted into a control tone to the noise inside the engine compartment on the noise source side or on the Ge räuschquellenende of the noise propagation path 71 to remove, ie in the vicinity 70 of the dashboard 80 , which separates the engine compartment 7 from the vehicle interior 8 .

Viewed from the inside of the vehicle, the result is nis the noise inside the engine compartment and the control tone in the same propagation path and delete each other off, creating a noise reduction effect over a large area is achieved.

FIG. 6 shows a diagram within the arrangement of a noise control system in accordance with a second embodiment of the present invention for controlling a noise (left side) that comes from outside the vehicle. The second embodiment differs from the first embodiment accordingly FIG. 2 in that the actuator 6 is arranged in the noise source side or at the noise source end of a propagation path from a noise source within the engine compartment to a space (left side) 91 outside the vehicle, that is, in a space within egg notor room 74 near an opening 73 which is located near the front left wheel. For this reason, the assignment information to be processed by the controller 44 corresponds to the information of the phase and amplitude controls of a control sound to reduce the engine revolution secondary component of the noise within the engine room 74 near the opening 73 of the front left wheel, during that of the actuator 6 from the control sound radiated corresponds to the sound for removing the noise within the engine compartment 74 at the aforementioned location of the engine compartment near the opening 73 from the front left wheel. As a result, viewed from the room (left side of the vehicle) 91 outside the vehicle, the noise inside the engine room 74 and the control sound pass through the same propagation path, whereby a noise reduction effect can be obtained over a wide range. It is readily apparent from the present invention that to achieve a similar noise reduction effect in a space (right side of the vehicle) 92 outside the vehicle, the actuator 6 in a space 76 inside the engine compartment near an opening 75 near the front right Wheel can be arranged.

According to FIG. 7 is a noise control system in accordance with egg ner third embodiment of the present invention for controlling noise (front side) which extend from outside of a vehicle shown a diagram of an arrangement. The third embodiment differs from the embodiment according to FIG. 2 in that the actuator 6 in the noise source side or at the noise source end of a propagation path 77 from a noise source within the engine compartment to a room (front of the vehicle) 93 outside the vehicle is arranged, ie in a space 79 within the engine compartment near a front grille opening 78 . Similar to the previously illustrated embodiments, a control sound radiated from the actuator 6 removes the noise within the engine compartment in the space 79 near the front grille opening 78 . Since - seen from the space (front) 93 outside the vehicle - the noise inside the engine compartment and the control sound pass through the same propagation path, the noise reduction effect can be achieved over a wide range.

Although the control signal for reducing the engine revolution secondary component has been obtained based on the map information with the engine revolution speed and the engine load as parameters in the previously illustrated embodiments, any type of system for obtaining the control signal, for example, a system for controlling another order component, may be obtained the No torum rotation or a feedback control system can be used as long as the noise at the position of the actuator 6 can be controlled, ie in the noise source side of the noise propagation path.

In addition, the present invention is not limited to the arrangement of the actuator 6 to the positions shown in these embodiments. For example, if a propagation path of a noise from a vehicle and transmitted inside or outside the vehicle can be determined, the actuator 6 may be arranged in the noise source side of the path.

According to FIG. 8 will be explained a fourth embodiment of the present invention. The fourth embodiment is intended to reduce the engine revolution secondary component radiated from an engine compartment outside or inside a vehicle. In this case, noise sources to be controlled include an intake noise emitted to the outside of the vehicle from an intake port, an outside noise from an opening of the engine compartment, and a resonance noise (pseudo noise source corresponding to a combination of noise sources within the engine compartment) within of the engine compartment, which are radiated into the vehicle interior via a dashboard. To accomplish the intended task, actuators are located near the intake port and within the engine compartment to perform 2-point noise control. Furthermore, the determination of the assignment information (phase and amplitude of each control tone) is carried out by a computer which performs the feedback control based on the steepest descent method using the quadratic sum of a concrete function (objective function) with respect to the interference sound pressures the engine revolution secondary component performs at two determination points or noise sources which are located near the intake port and within the engine compartment. In the present embodiment, microphones for the destination points, fast Fourier transformation (FFT) and a feedback control computer are only necessary for the time of determining the association information, and the actual control system includes a controller and actuators. Experimental results have shown that the present arrangement reduces the engine revolution secondary component by 5-10 dB at positions one meter from the left and right sides of the vehicle and at the position of the driver's ear. Although the feedback has actually been carried out to determine the mapping information related to the fourth embodiment, the effect of the control tones can be determined by simulation. Since the present example is intended to reduce noise, the feedback has been carried out on the basis of the steepest descent or descent method using the sum of squares as a concrete function of the interference tone pressures of determination points. However, in order to obtain a desired sound quality characteristic at the determination points, such feedback control can be performed to reduce a difference between the noises of the respective determination points and a desired sound quality characteristic.

The fourth embodiment of the present invention is illustrated in detail with reference to the accompanying figures. As mentioned above, FIG. 4 shows a diagram of a mounting arrangement of a 2-point noise control system in accordance with a fourth embodiment of the present invention to control vehicle noise. FIG. 9 shows a block diagram of a controller 83 of FIG. 8, and FIG. 10 shows phase controls and amplitude controls stored in a memory 838 of FIG. 9.

First, a detailed explanation regarding the noise control system is given. As shown in Fig. 8 Darge, is usually in an electronically steu er ing engine, an engine rotation sensor 81 within a manifold and an engine load sensor 82 such as an intake back pressure sensor is provided in a throttle body part. Both sensors are connected to the controller 83 via signal lines for transmitting such a motor rotation pulse signal 811 and motor load information signal 821 , as shown in FIG. 9. As further shown in FIG. 9, with respect to the structure of the controller 83, the motor revolution pulse signal 811 is applied to a shaping circuit 831 , which in turn is connected to a multiplier / frequency dividing circuit 832 and a low-pass filter 833 in this order. The output of the low-pass filter 833 is supplied to two paths, in one path it is subjected to a phase control circuit A 834 and an amplitude control circuit A 835 to be output as control waveform signal A 841, and in the other path it becomes a phase control circuit B 836 and one Subjected to amplitude control circuit B 837 to be output as control waveform signal 851 . In this case, the phase controls relating to the phase control circuit A 834 and the phase control circuit B 836 as well as the amplitude controls relating to the amplitude control circuit A 835 and the amplitude control circuit B 837 are determined by a central processing unit (CPU) 839 which processes the engine revolution speed and engine load is determined based on the engine revolution pulse signal 811 and the engine load information signal 821 , and reads out the corresponding association information from the memory 838 . In this connection, the assignment information relates to a phase control and an amplitude control for each actuator, which will be explained later. Furthermore, an actuator 84 (speaker) for the intake noise and an actuator 85 (speaker) for noise within the engine compartment are connected to the controller 83 via control waveform signal lines.

Next, an explanation will be given regarding the 2-point type noise control system of FIG. 8.

In the present embodiment, the engine is secondary rotation component (primary component of the explosion or combustion) of a 4-cylinder engine, which is a Pro blem as vehicle emission exterior and interior noise represents by controlling intake noise and engine reduced interior noise.

In detail, the controller 83 outputs control waveform signals (actuator input signals) for controlling the intake noise and the vehicle interior noise based on the mapping information based on the output signals of the notor rotation sensor 81 and the engine load sensor 82 in accordance with the engine condition (revolution speed and load) , which is shown in detail in connection with FIG. 9. The engine revolution pulse signal 811 as the output of the engine revolution sensor 81 is subjected to the shaping circuit 831 with respect to a noise removing operation, and thereafter to the multiplier / frequency dividing circuit 832 with respect to multiplier / frequency division operations to be converted into a pulse signal indicating the engine revolution secondary component. The secondary component pulse signal is then subjected to the low-pass filter 833 with respect to a harmonic component removal operation to be converted into a sinusoidal wave signal indicating the engine revolution secondary component. The sinusoidal wave signal of the secondary component is divided into two paths, it is subjected to the phase control circuit A 834 and the amplitude control circuit A 835 in a first path to be output as the phase controlled control waveform signal A 841, and in the second path it becomes the phase control circuit B 836 and the amplitude control circuit B 837 to be output as the amplitude controlled control waveform signal B 851.

Referring to Fig. 11, there is shown a flow chart for explaining a method of how the phase controls and amplitude controls on the phase control circuits A and B (834 and 836) and on the amplitude control circuits A and B (835 and 837) under the control of the CPU 839 are determined.

Specifically, the CPU 839 inputs the engine revolution speed information and the notor load information in a step S300 of FIG. 11. In step S301, it is judged whether there is a change in the rotational speed and the load areas. If the result of the judgment is negative, the system then returns to step S300. If the result of the assessment of step S301 is positive, the corresponding assignment information is then read out from the memory 838 in a step S302. In a step S303, the phases are determined at the phase control circuit A 834 and at the phase control circuit B 836.

In a step S304, the amplitudes are set on the amplitude control circuit A 835 or on the amplitude control circuit B 837. The control waveform signal A 841 and the control waveform signal B 851, which are output from the controller 83 , are converted by the intake noise actuator 84 and the engine interior noise actuator 85 into control tones for the intake noise and the noise within the engine compartment. In this case, since a distance between the laßgeräuse actuator 84 and the vehicle interior noise actuator 85 is small and the control tones emitted by the respective actuators have an identical frequency, is a control tone for simultaneously reducing the intake noise and the Engine interior noise different in phase and amplitude with respect to the control sound for reducing the intake noise only by the intake noise actuator 84 and with respect to the control sound for reducing the engine interior noise only by the engine interior noise actuator 85 . In the present method, the phase and amplitude controls of the control sound for simultaneously reducing the intake noise and the engine interior noise are stored in the memory 838 as association information. In this way, the intake noise and the engine interior noise as noise sources which are the engine revolutionary secondary component (primary component of the explosion or combustion) of a 4-cylinder engine in the vehicle emission exterior noise and interior noise by the control sound of the intake noise actuator 84 and the Control tone of the engine interior noise actuator 85 is reduced considering the interaction between the control tones. As a result, a large steering effect can be achieved inside and outside the vehicle.

In step S305, it is judged whether the control is to be ended. If the result of the assessment is negative the system then returns to step S300.

Next, an explanation will be given on how to determine the mapping information for simultaneously reducing intake noise and engine interior noise by using the intake noise actuator 84 and the engine interior noise actuator 85 , and how to assign the information of the memory 838 of FIG. 8 in a noise control system 2-point type of Fig. 12 is to be determined.

As shown in FIG. 12, the interconnections between the engine revolution sensor 81 , the engine load sensor 82 , the controller 83 , the intake noise actuator 84, and the engine interior noise actuator 85, as well as the internal structure of the controller 83, are essentially the same as those, which are shown in FIG. 8 Darge. However, the phase controls relating to the phase control circuit A 834 and the phase control circuit B 836 and the amplitude controls relating to the amplitude control circuit A 835 and the amplitude control circuit B 837 correspond to the values for the respective actuators which are obtained from a PC (personal computer) 89 in the Controller 83 can be created via an RS232C line. Interference tone pressures of control tones obtained by driving the intake noise actuator 84 and the vehicle interior noise actuator 85 using the phase and amplitude controls are provided by an intake noise microphone 86 provided near a destination 861 and by a vehicle interior noise microphone 87 , which is provided in the vicinity of a determination point 871 , is measured and applied to the PC 89 via a fast Fourier transformation analyzer (FFT analyzer) 89 .

As explained above, controller 83 outputs the control waveform signals (actuator inputs) for controlling intake noise and engine interior noise based on the outputs of engine revolution sensor 81 and engine load sensor 82 . In this method, the system of FIG. 9 is different from the system of FIG. 8 such that the phase and amplitude controls of the phase control circuit A 834, the amplitude control circuit A 835, the phase control circuit B 836 and the amplitude control circuit B 837 are not can be determined on the basis of the assignment information stored in the memory 838 of the controller 83 , but on the basis of the values applied to the controller 83 by the PC 89 . Thus, control tones having a given phase and amplitude are emitted from the intake noise actuator 84 and the engine interior noise actuator 85 , so that the PC 89 to the controller 83 analyzes the frequency analysis results of the FET analyzer 88 of the noise near the intake port of the determination point 861 and the noise inside the engine room of the determination point 871 , which was measured by the intake noise microphone 86 and the engine interior noise microphone 87 , respectively, so as to determine by the phase and amplitude controls to simultaneously determine the intake noise and reduce the engine interior noise. The phase and amplitude controls determined on the basis of the feedback in a normal running condition (revolution speed and load) of the engine have been stored in advance in the PC 89 as mapping information of the normal engine condition, and similarly, mapping can be done formations of all engine states can be found. After finding the mapping information for all engine conditions, the PC 89 sends the information via the RS232C line to the con troller 83 to the allocation information of the memory to update the controller 838 83rd When the noise control system of Fig. 8 is arranged in this way, the noise control system can suppress or reduce the intake noise and the engine interior noise at the same time. This algorithm is explained in detail.

Fig. 13 is a flowchart for explaining the assignment information determination algorithm of the 2-point noise control system of the fourth embodiment. The following procedure determines the optimal phase and amplitude controls to simultaneously reduce the intake noise and engine noise.

Shown in more detail, in a step S900 corresponding to FIG. 13, a vehicle to be measured is first driven on chassis rollers in a normal engine running (rotational speed and load), as is necessary with regard to the assignment information. In such a motor condition, the feedback is started with the initialization of a loop run or repetition number K. In step S901, the engine revolution information and the engine load information are input. In step S902, the presence or absence of a change in the rotational speed or a load range is determined. If there is a change in the speed of rotation or the load range, the feedback is ended. If it has been determined in step S902 that there is no change in the rotational speed or the load range, the interference tone pressures P1k and P2k of the engine revolution at the two measuring points are read out in step S903. In a step S904, a concrete function is calculated (the sum of the squares of the interference tone pressures of the second component: Wk = P1k² + P2k²).

In step S905, it is judged whether the concrete one Function is at its minimum value. If in step S905 determines that the concrete function is not at its minimum value, will be in egg In step 906, the phase and amplitude controls for modified the respective actuators. In one Step S907, the loop repetition number is increased and the system then returns to step S901 to complete the Enter engine revolution and load information, whereby a feedback loop is formed. If in that Step S905 determines that the specific function is at its minimum value, the phase and  Amplitude controls as allocation information regarding the engine state corresponding to step S905 draws, and at this stage the feedback is ended det. In accordance with the present embodiment form is passed to step S905 of judging whether the con function is at its minimum value, and step S906 of modifying the phase and amplitude the control for the respective actuators Ver drive the fastest descent or descent of the adaptations solution control used to converge the feedback provision loop.

When two actuators are activated at the same time become phase and amplitude control in this way rungen, which the simultaneous reduction of Einlaßge allow noise and engine interior noise than Allocation information is stored and it becomes a tax on the basis of the assignment information according to the engine revolution speed and the load information mation performed; the intake noise and the engine inside room noise can be reduced at the same time.

Fig. 14 is a diagram showing a mounting arrangement of a 3 point noise control system in accordance with a fifth embodiment of the present OF INVENTION dung to control a vehicle noise, and FIG. 15 shows a block diagram of the controller 83 of Fig. 14. The front lying invention is aimed to reduce the engine revolution secondary component (primary component of the explosion or combustion) of a 4-cylinder engine, the difficulty of a vehicle emission exterior noise and interior noise arising from the control of the intake noise, the engine interior noise and the exhaust noise. In the 3-point noise control system of the present embodiment shown in FIG. 14, an exhaust noise actuator 100 has been additionally added. The present fifth embodiment differs from the fourth embodiment according to FIG. 8 in that the output signal of the low pass filter 833 is supplied with three paths, and a phase control circuit C 340 and an amplitude control circuit C 350 are additionally added to a control waveform signal C 101 to be provided. Furthermore, the fifth embodiment is the same as the fourth embodiment with respect to the control algorithm of the controller 83 , but differs from the fifth embodiment in that since the phase and amplitude controls are determined on each control waveform signal, the mapping information to be stored in the memory 838 is the same Phase and amplitude controls of three control tones for simultaneous reduction of the intake noise, the engine interior noise and the exhaust noise by the intake noise actuator 84 , the interior noise actuator 85 and the exhaust noise actuator 100 corresponds. In this way, the intake noise, the engine interior noise and the exhaust noise as noise sources contributing to the engine revolution secondary component (primary component of the explosion or combustion) of the 4-cylinder engine as vehicle emission exterior noise and interior noise, simultaneously by the control sounds of the intake noise Actuator 84 , the engine interior noise actuator 85 and the exhaust noise actuator 100 are reduced who, with interactions between the control tones taking place, resulting in a large control effect, which can be observed outside and inside the vehicle.

Fig. 16 is a diagram for explaining a Mechanical- mechanism for determining the allocation information within the memory 838 of Fig. Explained 15. As shown, the allocation information determination mechanism of the fifth embodiment differs from that in the noise control system of the fourth embodiment in that the Auslaßgeräusch- Actuator 100 and an exhaust noise microphone 200 in the vicinity of a determination point 201 are additionally provided and that, as shown in FIG. 15, the output signal of the low-pass filter 833 is fed to three paths and that the phase control circuit C 340 and the amplitude control circuit C 350 are additional Lich are added to provide the control waveform signal C 101. The fifth embodiment and the fourth embodiment are the same in that the phase and amplitude controls are determined not on the basis of assignment information but on the basis of the values which are applied from the PC 89 to the controller 83 . As a result, control tones having a given phase and amplitude are radiated from the intake noise actuator 84 , the engine interior noise actuator 85, and the exhaust noise actuator 100 , so that the PC 89 to the controller 83 receives the frequency analysis results of the FFT analyzer 88 of the Geräu cal near the inlet port of the determination point 861 , the noise inside the engine compartment of the determination point 871 and the outlet noise of the determination point 201 , which are measured by the inlet noise microphone 86 , the engine interior noise microphone 87 and the outlet noise microphone 200 are returned, whereby the Pha sen- and amplitude starters are determined to simultaneously reduce the intake noise, the engine interior noise and the exhaust noise.

Fig. 17 shows a flowchart for explaining the assignment information determination algorithm in the 3-point noise control system of the fifth embodiment.

As corresponding to FIG. 17, the fifth embodiment from the fourth exporting different approximate shape is that the step S903 of reading the Inter ferenztondrücke the engine revolution secondary component at the two measurement points, and the step S904 of the calculation of the specific function (sum of the squares of the interference tone press the secondary component at the two points) accordingly Fig. 13 by a step S913 of reading In terferenztondrücken P1k, P2k and P3k the Motorumdrehungsse kundärkomponente at three measurement points, and a step S914 of calculating a specific function (sum of squares of Interferenztondrücke the secondary component to the three points: Wk = P1k² + P2k² + P3k²). In this way, the three actuators are controlled simultaneously to find phase and amplitude controls as assignment information which allow simultaneous reduction of the intake noise, the engine interior noise and the exhaust noise.

Although the engine revolution secondary component (Primary component of the explosion or combustion) of the 4-cy linder engine, in which the difficulty of driving exterior and interior noise occurs, by controlling the intake noise, the engine interior noise and the outlet noise in the foregoing management forms has been reduced, the order or the rank of the engine revolution to be controlled does not depend on the Secondary component limited, but it can be another Rank or another order of the component used the. Furthermore, the noise sources to be controlled not limited to those shown, but can multiple sources of noise that lead to vehicle emissions exterior noise and interior noise contribute to one umpteenth pseudo noise source.

Furthermore, since the above embodiments is aimed at reducing noise, the serves in steps S904 and S914 for calculating the function in use the mapping information determination algorithm th concrete function, a sum of squares of the To find interference tone pressures at the measuring points. If ever but it is desired to send desired interference tone pressures to the  To determine the respective measuring points, the specific radio tion depending on your tax subject be placed. For example, the specific function is there to determine a sum of squares of differences between desired and actual tone pressures on the To find measuring points. In addition, the present the embodiment the method of steepest descent or descent of the adjustment control in step S905 to assess whether the specific function is on your mi nominal value, and in step S906 of the Modifi adorn the phase and amplitude controls with respect to respective actuators have been used. It can ever but some other method than the one outlined above can be used as long as such phase and ampli Controls of control tones to cause the concrete functions are at their minimum value that can be determined.

Although the feedback has actually been done is to map information in the embodiments so To determine as much as possible can also cause interference tone pressures at the respective measuring points using the Amplitude and phase of each measurement point are calculated, if no control is carried out, and also with Ver application of an estimated value of a tone which is from each actuator arrives and by multiplying egg control sound as the output signal of each actuator by a transfer function from each actuator is obtained for each measuring point in order to obtain the assignment information to determine.

In the fourth and fifth embodiments above an assignment has been made, which is determined by Ab buttons of current tones has been obtained. However, can the assignment are made by simulation, the Procedure detailed in connection with a sixth off management form is presented.  

First, in such a tone measuring system, as shown in FIG. 18, vehicle noises in the non-control mode under a load condition necessary for making the assignment at the determination points 31 , 32 , 33 , 34 and 35 , as well as sounds at the determination points 31 , 32 , 33 , 34 and 35 , which are transmitted when a controller 13 is used to drive the respective actuators of Figs. 21 and 22 independently of each other in accordance with the engine revolution order component, are specifically measured as follow-up data on the engine revolution to perform an order ratio trucking analysis ) to carry out. In this case, the order values (the phases and amplitudes to be controlled) are recorded when each actuator is activated.

Next, the mapping information is determined at a given revolution speed and load conditions in accordance with a flow chart of FIG. 19. Specifically measured data are entered in a step S 101, while an audio pressure P _{i obj is} entered as a control _target or target control for the respective determination points in a step S102. Then a loop is executed. That is, since the phase and amplitude to be controlled are changed, a tone pressure Pik of each determination point is calculated as a control result by a simulation in a step S104. In a step S105, the squares of the differences between the tone pressures P _{i obj} as _{control targets} at the respective determination points and the tone pressures Pik as control results are calculated and multiplied and summed with a weighting function Wi with respect to the determination points in order to obtain a specific function Wk. In a step S106 it is determined whether the specific function Wk is at its minimum value. If it is determined that the particular function is not at its minimum value, the phase and amplitude are modified in step S107, the loop repetition number is increased in step S108, and the system returns to step S104. If it is determined in step S106 that the concrete function Wk is at its minimum value, the assignment information is stored in a step S109 and the process is ended. In the present embodiment, the method of the deepest drop is used to judge whether the specific function is at its minimum value in accordance with step 106, and to modify the phase and the amplitude in accordance with step S107. The simulation of the control result is performed by superimposing the transmission tones of the output signals of the respective actuators, the phase and amplitude of which are determined by the association information regarding the vehicle noise at the time of the non-control in accordance with the sound wave superimposition principle, taking the phase and the amplitude into account.

When necessary mapping information is determined in accordance with the flowchart of Fig. 19 regarding each of the rotational speed and load conditions, such mapping information can be obtained to cause the control results to be acquired near the control targets at the respective destinations.

Although a necessary tax result is experimental for any rotational speed and load conditions correspond According to the state of the art, the assignment Information can easily be obtained only through con Crete measuring vehicle noise at the time of not control under load conditions, which are necessary for closing order preparation, and the transmission tones of the respective determination points if the respective actuation the mutually independent in the form of sequence  data relating to the engine revolution are controlled, and by performing the simulation in the present Aus management form. Furthermore, the assignment information can be easily obtained by performing the simulation in of the present invention, although every time that Tax target is changed, the experiment according to the State of the art must be carried out.

In addition, if the predetermined weighting function Wi for each of the determination points can be multiplied the desired control tones can be easily obtained.

As explained above, there is agreement tion with the present invention, the actuator in the noise source side or at the noise source end of the sound propagation path through which the noise emitted by the vehicle from the vehicle transmitted or into the vehicle, it will the control waveform signal generated to the actuator to cause the control sound to control the noise radiate, and information is obtained which is necessary to generate the control waveform signal. Since that Control waveform signal from the actuator to the Control tone for controlling the noise is transmitted, can therefore be noise from many sources of noise finally run out of the engine through the actuating link which corresponds to a small number of transmission paths being controlled. Furthermore, the noise and the Control tone of the actuator by the same transmission path out of the vehicle and into the vehicle can be emitted, the noise and the tax tone reproduce in the same way and thus via egg a wide range can be controlled.

A noise control system has been disclosed above beard, in which a noise generated by an engine is caused with a control tone of an actuator  to interfere to attenuate the noise of the engine or to convert the sound into a sound that is ge has desirable characteristics, which makes noises outside and inside a vehicle with respect to a ge desired tone characteristics can be processed. In the sy stem is an actuator in a noise source side or at a noise source end of a noise propagation arranged through which one of the vehicle radiated noise out of or into the vehicle Vehicle is transferred into it, a controller that works with the actuator is connected, generates a Steuerwel lenform signal to cause the control tone to control the noise is emitted by the actuator, and sensors connected to the controller This is the data that is necessary to generate the controller to cause gene of the control waveform signal, for example wise data regarding the engine revolution information and the engine load information.

Claims (23)

1. Noise control system with:
detection means ( 1 , 2 ; 81 , 82 ) for detecting information relating to the vehicle;
control signal generating means ( 4 ; 83 ) for generating a control waveform signal for controlling a noise emitted from a vehicle in response to an output signal of said detection means, and
a control sound generating device ( 6 ; 84 , 85 ), which is arranged in a noise source side or at a noise source end of a noise propagation path ( 71 ; 72 ) through which the vehicle emission noise is transmitted from or into the vehicle, to Supplying a control tone to cause the noise in the noise propagation path to interfere in response to a signal received from the control signal generating means. 2. Noise control system according to claim 1, characterized ge indicates that the control tone generating device on the Noise source end of at least one noise propagation tongue path is provided, which egg from the inner space engine compartment of the vehicle runs into the vehicle interior or wherein the sound propagation path from the inside of the engine compartment runs out of the vehicle. 3. Noise control system according to claim 2, characterized ge indicates that the control tone generating device at egg nem end of the noise propagation path near the engine space of the vehicle is provided.   4. Noise control system according to claim 1, characterized ge indicates that the control tone generating device is internal half of an engine compartment of the vehicle and near one Dashboards is arranged, which the engine compartment of separates the vehicle interior. 5. Noise control system according to claim 1, characterized ge indicates that the control tone generating device is internal half of an engine compartment of the vehicle and near one Grille opening on the front outside of the vehicle is arranged. 6. Noise control system according to claim 1, characterized ge indicates that the detection device a revolution speed detection device for detection a rotational speed of one in the vehicle brought engine. 7. Noise control system according to claim 6, characterized in that the control signal generating device
a signal generating device for generating a signal which has a frequency corresponding to a desired state or order based on the information relating to the vehicle, which was detected by the rotational speed detection device,
a memory device which contains a control assignment of a phase and an amplitude corresponding to the rotational speed of the motor stored therein, and
signal modifying means for performing phase and amplitude control on a signal generated by the signal generating means in response to the phase and amplitude read out from the storage means using the detected engine revolution speed. 8. Noise control system according to claim 1, characterized ge indicates that the detection device is a motor Rotational speed detection device for detection the rotational speed of the in the vehicle brought engines and an engine load detection device for detecting a load on the engine. 9. Noise control system according to claim 8, characterized in that the control signal generating device
has signal generating means for generating a signal having a frequency corresponding to a desired state or order on the basis of the information relating to the vehicle, which has been detected by the engine rotational speed detection device and the engine load detection device,
a memory device containing a control map which has phase and amplitude data corresponding to the engine revolution speed and engine load stored therein, and
signal modifying means for performing the phase and amplitude control over the signal generated by the signal generating means in response to the phase and amplitude read out from the storage means using the detected engine revolution speed and the engine load. 10. Noise control system according to claim 6, characterized in that the control signal generating device
a signal generating device for generating a signal having a frequency corresponding to a desired state on the basis of the information relating to the vehicle, which was detected by the detection device,
a memory device that has a control map with data relating to a phase and an amplitude corresponding to the interference noises generated by a plurality of the noise sources stored therein within the engine room in response to the engine revolution speed, and
has a signal modification means for performing the phase and amplitude control over the signal generated by the signal generating means in response to the read out from the control assignment phase and Am plitude using the detected engine rotation speed. 11. A noise control system according to claim 10, therein ge indicates that the sound generating device controls sounds according to the signal of the signal modification direction generated to the interference noise within the To cause the vehicle to interfere with the control sound ren. 12. Noise control system according to claim 11, characterized ge indicates that a plurality of control sound generation directions is provided. 13. Noise control system according to claim 12, characterized ge indicates that the storage device is data related the phase and the amplitude corresponding to one of one of the control tone generation present in a plurality directions generated control tone in response to the Mo gate speed stores.   14. Noise control system according to claim 12, characterized ge indicates that the storage device is data related phase and amplitude stores to cause sen that one of one of the plural Control sound generating devices generated control sound ent is removed. 15. Noise control system according to claim 12, characterized ge indicates that one of one is in a plurality lying control sound generating devices generated tax erton with one of the other control tone generating device generated control sound interferes. 16. Noise control system according to claim 8, characterized in that the control signal generating device
a signal generating device for generating a signal having a frequency corresponding to a desired state or order on the basis of the information relating to the vehicle, which has been detected by the engine rotational speed detection device, the engine load detection device,
a storage device having a control map with data relating to a phase and an amplitude corresponding to the interference noise generated by a plurality of noise sources stored therein within the engine room in response to the engine revolution speed and the engine load, and
signal modifying means for performing phase and amplitude control over the signal generated by the signal generating means in response to the phase and amplitude read from the control map using the detected engine revolution speed and engine load. 17. Noise control system according to claim 16, characterized ge indicates that the control tone generating means one Control tone according to the signal of the signal modification device generates the interference noise within of the vehicle to cause the steering tone to interfere. 18. Noise control system according to claim 17, characterized ge indicates that a plurality of control sound generation directions are provided. 19. Noise control system according to claim 17, characterized ge indicates that the storage device is data related a phase and an amplitude corresponding to a control ton, which is one of those in a plurality Control sound generating devices was generated in the Anspre Chen saves on an engine revolution speed. 20. Noise control system according to claim 17, characterized ge indicates that the storage device is data related a phase and an amplitude stores to cause that a control tone is removed which is from one of the in a He has a plurality of control tone generating devices was fathered. 21. Noise control system according to claim 17, characterized ge indicates that a control tone emitted by one of the in a He has a plurality of control tone generating devices was generated with one of the other control tone generation device generated control tone interferes.   22. Noise control system according to claim 7, characterized ge indicates that the tax allocation through a simulation is made. 23. Noise control system according to claim 22, characterized ge indicates that when making the tax assignment by weighting a simulation with respect to the to be controlled Determination points is carried out.