JPH08338592A - Power plant support device - Google Patents

Abstract

PURPOSE: To provide a power plant support device which can surely reduce indistinct sound issued into a vehicle cabin. CONSTITUTION: A drive signal determining part 21 of a controller 10 computes a vector sum A2 +Bh2 where A2 is an estimated indistinct sound caused by vibration transmitted through a right engine mount, and Bh2 is an estimated indistinct sound caused by vibration transmitted through a rear engine mount during high rigidity, and a vector sum A2 +Bs2 where Bs2 is an estimated indistinct sound caused by vibration transmitted through the rear engine mount during low rigidity. Further, when the vector sum A2 +Bh2 is less, it is considered that the rear engine mount with high rigidity is advantageous in reducing the indistinct sound so that a control signal I is delivered. Meanwhile, if the vector sum A2 +Bs2 is less, it is considered that the rear engine mount with a low rigidity is advantageous in reducing the indistinct sound, the delivery of the control signal I is stopped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a supporting device for supporting a power plant composed of a vehicle engine, a transmission and the like on a vehicle body, and more particularly, to more reliably reduce the muffled noise radiated into the vehicle interior. It is the one.

[0002]

2. Description of the Related Art A conventional supporting device for a power plant 1 is
For example, it is as shown in FIG. 20, which is a schematic plan view of the vehicle 2. Note that, in FIG. 20, the left side is the vehicle front side.
That is, the power plant 1 of the vehicle 2 is composed of a horizontal engine 1A and a transmission 1B, and elastically attached to the vehicle body 2A via four engine mounts 3A to 3D composed of rubber elastic bodies or the like. It is supported. The output side of the transmission 1B is connected to a front wheel drive shaft 1C extending in the left-right direction of the vehicle so that driving force can be transmitted, and both ends of the drive shaft 1C are transmitted to front wheels 4FL and 4FR as driving wheels. Connected possible. In other words, this vehicle 2 is a so-called horizontal engine FF (front engine / front drive).
It is a vehicle.

On the other hand, four engine mounts 3A to 3D
Of the right engine mount 3A, which is located on the right side of the vehicle
And the left engine mount 3B arranged on the left side of the vehicle,
The front engine mount 3C arranged between the power plant 1 and the vehicle body 2A and arranged on the vehicle front side and the rear engine mount 3D arranged on the vehicle rear side extend below the power plant 1 in the vehicle front-rear direction. Center member 5
And the power plant 1. The front end of the center member 5 is directly connected to the vehicle body 2A, and the rear end of the center member 5 is connected to the lower surface side of the subframe 6 extending in the vehicle left-right direction by welding or the like. Also,
Each of the left and right ends of the sub-frame 6 has insulators 7, ...
It is elastically coupled to the vehicle body 2A via 7.

Since a front suspension arm or the like (not shown) is connected to the subframe 6 used in such a general vehicle 2, the front wheels 4FL and 4FR are input from the road surface while the vehicle is traveling. The generated vibration is input to the sub-frame 6 through the front suspension arm or the like, and is transmitted to the vehicle body 2A side, which may be one factor of deterioration of the vehicle body side vibration level. However, the insulators 7, ..., 7 interposed between the subframe 6 and the vehicle body 2A
21, the force transmissibility between the sub-frame and the vehicle body can be reduced in a region of a predetermined frequency f ₀ or higher, so that the insulator 7, By appropriately setting the support rigidity of 7 ... and making the frequency f ₀ lower than the frequency of the vibration input from the road surface side, the vibration transmitted from the road surface to the vehicle body 2A side through the sub-frame 6 can be reduced. it can.

However, since the vibration transmissibility between the subframe 6 and the vehicle body 2A is large for vibrations of a frequency lower than the frequency f ₀ shown in FIG. 21, for example, a vehicle equipped with an in-line 4-cylinder engine starts. In this case, or when the vehicle is cruising at a low engine speed, when the secondary component of the engine rotation having a large excitation force stays in a frequency band lower than the frequency f ₀ for a relatively long time, the vibration is generated in the subframe. It is amplified when it is transmitted to the vehicle body 2A via 6, and this is amplified by the vehicle body 2
There is a problem in that it may propagate A and be radiated into the passenger compartment 8 to generate an unpleasant muffled sound.

As a conventional technique capable of solving such a problem, Japanese Patent Laid-Open No. 5-21 previously proposed by the present applicant.
There is one disclosed in Japanese Patent No. 3039. That is, in the technique described in this publication, the subframe and the vehicle body are coupled to each other via a coupling element whose support stiffness is variable, and the supporting stiffness of the coupling element is appropriately adjusted according to the windup state of the subframe. As a result, both the reduction of the vibration input from the road surface and the suppression of the fluctuation of the suspension geometry are achieved.

That is, at least one of the insulators 7, ..., 7 shown in FIG. 20 is used as a stiffness variable element for varying the support stiffness, and the engine rotation secondary component has a frequency f.
_{When the} frequency becomes lower than _0, the supporting rigidity of the rigidity variable element is appropriately changed, and the subframe 6 and the vehicle body 2
It is conceivable that the vibration transmissibility between A is always kept small.

[0008]

However, according to the experiments conducted by the present inventors, the muffled noise is generated even if the control for reducing the vibration transmissibility between the sub-frame 6 and the vehicle body 2A is executed as described above. It has been confirmed that it cannot be reduced sufficiently. That is, FIG. 22 is a result of measuring the vehicle body radiation coefficient for each of the case where the subframe 6 of the vehicle 2 shown in FIG. 20 and the vehicle body 2A are connected with high rigidity and the case where they are connected with low rigidity. Further, FIG. 23 shows the results of actually measuring the muffled noise (secondary component of engine rotation) generated in the vehicle interior 8 in the same two cases of the vehicle 2 shown in FIG. The vehicle body radiation coefficient in this case is a coefficient representing the relationship between the unit force input to the sub-frame 6 and the noise level in the vehicle interior 8, and the vibration of the sub-frame 6 is used as an input to determine the interior of the vehicle interior 8. It is synonymous with the transfer function whose output is the noise level of.

It can be seen from FIG. 22 that the radiation coefficient becomes smaller in many frequencies when the high rigidity coupling is made than in the low rigidity coupling. Therefore, it can be estimated that the muffled sound is less likely to occur at many frequencies when the high rigidity coupling is performed. However, comparing FIG. 22 and FIG. 23, it is found that the magnitude of the radiation coefficient and the noise level do not always match. That is, in the case where the vehicle interior noise caused by the vibration input from the sub-frame 6 has a phase substantially opposite to that of the vehicle interior noise passing through another transmission path, and has a function of canceling the noise, , At a certain frequency, the insulators 7, ...
Even if the level of vibration transmitted to is reduced, the muffled sound may worsen. For this reason,
Even if the supporting rigidity of the variable rigidity element is appropriately changed only in accordance with the frequency of the secondary engine rotation component, the level of the muffled sound in the vehicle interior 8 could not always be reduced.

The present invention has been made in view of the above-mentioned conventional problems, and provides a power plant supporting device capable of more reliably reducing the muffled noise radiated into the vehicle interior. Is intended.

[0011]

In order to achieve the above object, the invention according to claim 1 is a sub-frame coupled to a vehicle body through at least one coupling element, and a vehicle power plant including an engine. In a power plant supporting device comprising a plurality of supporting elements interposed between the vehicle body and between the power plant and the sub-frame, at least one supporting element is included in the coupling element or the supporting element. At least one of the elements is a variable rigidity element with variable support rigidity, and
A first vibration detecting means for detecting a vibration passing through the one stiffness variable element; a first extracting means for extracting a predetermined order component of engine rotation from the vibration detected by the first vibration detecting means; Second vibration detecting means for detecting vibrations passing through the coupling element or the supporting element other than the one stiffness variable element, and a predetermined order component of engine rotation is extracted from the vibration detected by the second vibration detecting means. The second extracting means, the first estimating means for estimating the vehicle interior noise caused by the component extracted by the first extracting means, and the vehicle interior noise caused by the component extracted by the second extracting means Second to estimate
Of the vehicle interior noise estimated by the first estimation means and the vehicle interior noise estimated by the second estimation means, the support stiffness of the stiffness variable element is controlled so that the vector sum thereof becomes minimum. And rigidity control means.

In order to achieve the above object, the invention according to claim 2 is such that a subframe coupled to a vehicle body through at least one coupling element, a power plant of a vehicle including an engine and the vehicle body, and In a power plant supporting device provided with a plurality of supporting elements respectively interposed between the power plant and the sub-frame, at least one of the coupling element or each element included in the supporting element. One element is a variable rigidity element with variable support rigidity, and a vibration detecting means for detecting vibrations passing through the one variable rigidity element, and a predetermined order component of engine rotation is extracted from the vibration detected by this vibration detecting means. The first extracting means, the noise detecting means for detecting the vehicle interior noise, and the noise detected by the noise detecting means Second extracting means for extracting a constant order component, estimating means for estimating a vehicle interior noise caused by the component extracted by the first extracting means, component extracted by the second extracting means and the estimating means The vector difference calculation means for calculating the vector difference with the vehicle interior noise estimated by the above, and the support rigidity of the rigidity variable element so as to minimize the vector sum of the vector difference and the vehicle interior noise estimated by the estimation means. And a rigidity control means for controlling.

According to a third aspect of the present invention, in the power plant supporting apparatus according to the first or second aspect of the present invention, the mass body is attached to the subframe through an attachment element with variable support rigidity. The rigidity control means controls the supporting rigidity of the variable rigidity element and the mounting element so that the vector sum is minimized.

According to a fourth aspect of the invention, in the power plant supporting apparatus according to the first to third aspects of the invention, at least one of the coupling elements is the variable rigidity element, and A rotation speed detection means for detecting an engine rotation speed is provided, and the rigidity control means sets a state in which the support rigidity of the rigidity variable element included in the coupling element is low when the engine rotation speed is equal to or higher than a predetermined rotation speed. I kept it at.

Further, the invention according to claim 5 is the power plant supporting apparatus according to any one of claims 1 to 4, wherein at least one of the coupling elements is the variable rigidity element, A vehicle speed detecting means for detecting the vehicle speed is provided, and the rigidity control means maintains the supporting rigidity of the variable rigidity element included in the coupling element in a low state when the vehicle speed is equal to or higher than a predetermined vehicle speed. .

According to a sixth aspect of the present invention, in the power plant supporting device according to the first to third aspects, at least one of the coupling elements is the variable rigidity element, and the engine rotation speed is increased. A rotation speed detection means for detecting the number of revolutions, and a suction negative pressure detection means for detecting the suction negative pressure of the power plant; and the rigidity control means, when the engine speed is equal to or higher than a predetermined rotation speed, or When the suction negative pressure is equal to or lower than a predetermined pressure, the support rigidity of the variable rigidity element included in the coupling element is maintained in a low state.

[0017]

In the invention according to claim 1, among the vibrations generated in the power plant, the vibration passing through one stiffness variable element is detected by the first vibration detecting means, and the one stiffness variable element is detected. The vibration passing through the coupling element or the supporting element other than (the stiffness variable element which is the path of the vibration detected by the first vibration detecting means) is detected by the second vibration detecting means.

Then, the nth-order (n is a positive real number) component of the engine rotation included in the vibration detected by the first vibration detecting means is extracted by the first extracting means, and the second extracting means The nth-order component of the engine rotation included in the vibration detected by the second vibration detecting means is extracted. It should be noted that, as the nth-order component of the engine rotation here, a rotation order component having a large influence on the vehicle interior noise is selected, and the nth-order rotation component extracted by the first extracting means and the second extraction component. The rotation nth order component extracted by the means propagates through the vehicle body or the like to reach the floor or the like of the vehicle compartment, and the floor is vibrated by them to generate a muffled sound in the vehicle compartment.

The first estimating means estimates the vehicle interior noise caused by the nth-order rotation component extracted by the first extracting means, and the second estimating means estimates the rotation noise extracted by the second extracting means. The vehicle interior noise caused by the nth-order component is estimated. However, if the support rigidity of one variable stiffness element changes, the vibration transmission characteristics of that variable stiffness element change, and the amplitude and phase of the vibration that passes through the variable stiffness element also changes. The vehicle interior noise caused by the change will change. Therefore, the estimation result by the first estimating means varies depending on the change state of the support rigidity of the one variable rigidity element.

Then, the vehicle interior noise estimated by the first estimating means and the vehicle interior noise estimated by the second estimating means are generated in the vehicle interior, respectively, and the combined noise is generated for the occupant. As is audible, the stiffness control means minimizes the vector sum of the vehicle interior noise estimated by the first estimating means and the vehicle interior noise estimated by the second estimating means for the support rigidity of the variable stiffness element. Since the vehicle interior is controlled as described above, the vehicle interior noise that can be heard by the occupant is minimized within a possible range.

According to another aspect of the invention, the vibration detecting means detects the vibration passing through the one stiffness variable element, and the first extracting means includes the vibration included in the vibration detected by the vibration detecting means. The nth order component of rotation is extracted. On the other hand, the noise detecting means detects the vehicle interior noise, and the second extracting means extracts the nth-order component of the engine rotation included in the detected vehicle interior noise. Therefore, the extraction result of the second extracting means combines all the noise components due to the n-th order component of the engine rotation included in the vibration propagating in all the paths existing between the power plant and the vehicle interior. It becomes the ingredient.

Then, the estimating means estimates the vehicle interior noise caused by the component extracted by the first extracting means, and the vector difference between the component extracted by the second extracting means and the vehicle interior noise estimated by the estimating means. Is calculated by the vector difference calculation means. Here, the vector of the vehicle interior noise estimated by the estimation means is based on the vibration passing through one stiffness variable element, and the vector calculated as the vector difference by the vector difference calculation means is the one stiffness variable element. It is based on vibrations passing through all other vibration paths except the vibration path including.

That is, according to the second aspect of the present invention, the vehicle interior noise actually generated is the vehicle interior noise estimated by the estimating means and the vehicle interior noise corresponding to the vector difference calculated by the vector difference calculating means. Moreover, when the supporting rigidity of one variable stiffness element changes, the amplitude and phase of the vibration passing through that variable stiffness element also changes. It varies depending on the changing state of the support rigidity of the variable element.

Therefore, also in the invention according to claim 2, the rigidity control means calculates the support rigidity of the rigidity variable element by the vector sum of the vehicle interior noise estimated by the estimation means and the vector difference calculated by the vector difference calculation means. When the control is performed to minimize the noise, the vehicle interior noise heard by the occupant is minimized in the possible range. In the invention according to claim 3, in the case where the mass body mounted on the subframe via the mounting element with variable support rigidity is such that the resonance frequency of the subframe and the resonance frequency of the mass body are substantially the same. Functions as a dynamic vibration absorber. However, when the resonance frequency of the subframe and the resonance frequency of the mass body are significantly deviated, the mass body functions to invert the phase of the force transmission system via the subframe at a certain frequency. And
The resonant frequency of the mass can be adjusted by changing the support stiffness of its mounting element.

Therefore, if the support rigidity of the mass body is adjusted appropriately, the vector sum in the invention according to claim 1 or 2 also changes, so the degree of freedom of control in the rigidity control means increases, and the vehicle interior. The control range of noise is expanded. In the invention according to claim 4, the engine speed is detected by the engine speed detection means, and the rigidity control means, when the engine speed is equal to or higher than a predetermined speed,
The supporting rigidity of the variable rigidity element included in the coupling element is maintained in a low state. That is, when the engine speed is higher than or equal to a predetermined speed and the frequency of vehicle interior noise caused by engine vibration is higher than or equal to a predetermined frequency, it is not possible to obtain a sufficient noise reduction allowance by changing the support rigidity of the rigidity variable element. However, in such a situation, the coupling between the subframe and the vehicle body becomes low in rigidity, and the vibration input of the power plant is preferentially exerted by the function of isolating the vibration by the subframe.

According to the invention of claim 5, the vehicle speed is detected by the vehicle speed detecting means, and the rigidity control means, when the vehicle speed is equal to or higher than a predetermined vehicle speed, the supporting rigidity of the variable rigidity element included in the coupling element. Keep it low. That is, even if the vehicle speed becomes higher than or equal to the predetermined vehicle speed and the vibration input from the road surface to the sub-frame via the suspension becomes large, the coupling between the sub-frame and the vehicle body becomes low in rigidity, and the vibration input from the road surface is The function of vibration isolation by the frame will be given priority.

In the invention according to claim 6, the engine speed is detected by the engine speed detecting means, and the suction negative pressure of the power plant is detected by the suction negative pressure detecting means.
The rigidity control means maintains the support rigidity of the variable rigidity element included in the coupling element in a low state when the engine speed is equal to or higher than the predetermined speed and when the suction negative pressure is equal to or lower than the predetermined pressure. That is, the control by the rigidity control means is executed only in a situation where the muffled noise is apt to occur due to the low engine speed and high engine load, and the vibration isolation function by the subframe is prioritized in other situations.

[0028]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 are views showing a first embodiment of the present invention. First, the configuration of the present embodiment will be described with reference to FIGS. The same components as those of the conventional power plant 1 supporting apparatus shown in FIG. 20 are designated by the same reference numerals.

That is, even in this embodiment, as shown in FIG. 1 which is a schematic plan view of the vehicle 2, the power plant 1 is
It is elastically supported by the vehicle body 2A via the right engine mount 3A and the left engine mount 3B as supporting elements, and elastically supported by the center member 5 via the front engine mount 3C and rear engine mount 3D as supporting elements. The front end of the center member 5 is directly connected to the vehicle body 2A, and the rear end of the center member 5 is the subframe 6
, And the left and right ends of the sub-frame 6 are elastically coupled to the vehicle body 2A via insulators 7, ..., 7 as coupling elements.

Here, in the vehicle 2 of the present embodiment, the main paths of vibrations generated in the power plant 1 and transmitted to the vehicle body 2A are the path passing through the right engine mount 3A, the rear engine mount 3D, and the sub engine mount 3D. There are two paths, that is, a path passing through the frame 6 and the insulators 7, ...
In this embodiment, the four engine mounts 3A to
Of the 3D, the support rigidity of the rear engine mount 3D included in one of the two main paths of vibration described above is variable according to the control signal I supplied from the controller 10. The rear engine mount 3D includes, for example, a rubber elastic body interposed between the power plant 1 and the center member 5, a main fluid chamber formed in the rubber elastic body, and a sub fluid chamber defined by a diaphragm or the like. , The orifice that connects the main fluid chamber and the sub fluid chamber to each other, the fluid enclosed in the main fluid chamber, the sub fluid chamber, and the orifice, and the two positions that make the orifice in the communicating state and the blocking state A blocking member, a spring for urging the blocking member toward a position in which the blocking member is in communication, and a control signal I
And an excitation coil for energizing the breaking member toward the cut-off state while resisting the biasing force of the spring by exciting the control signal I to the exciting coil.
When the rubber is not supplied, the orifice is in communication and the main fluid chamber and the sub fluid chamber communicate with each other, the fluid in the main fluid chamber escapes to the sub fluid chamber side when the rubber elastic body is compressed and elastically deformed. When the elastic body is expanded and elastically deformed, the fluid in the sub-fluid chamber is supplied to the main fluid chamber, so the dynamic spring constant of the rubber elastic body becomes low, and the support rigidity of the rear engine mount 3D becomes low. On the other hand, when the control signal I is supplied to the exciting coil, the blocking member moves and the orifice is blocked so that the main fluid chamber and the sub-fluid chamber are shut off, and the fluid in the main fluid chamber is It ’s impossible to move,
The dynamic spring constant of the rubber elastic body becomes high, and the support rigidity of the rear engine mount 3D becomes high.

That is, the support rigidity of the rear engine mount 3D is variable in two steps, such as low rigidity when the control signal I is not supplied and high rigidity when the control signal I is supplied. Has become. On the other hand, in the vicinity of the portion of the subframe 6 to which the center member 5 is coupled, the acceleration for detecting the vibration transmitted from the power plant 1 to the subframe 6 via the rear engine mount 3D and the center member 5. The sensor 11 is fixed,
The vibration acceleration detected by the acceleration sensor 11 is supplied to the controller 10 as an acceleration detection signal D ₁ .

In addition, among the parts of the vehicle body 2A, in the vicinity of the part where the right engine mount 3A included in the other of the two main paths of the above-mentioned vibration is disposed, the power plant 1 and the right engine mount 3A are located near the part. Via car body 2
Acceleration sensor 12 for detecting vibration transmitted to A
Is fixed, and the vibration acceleration detected by the acceleration sensor 12 is used as the acceleration detection signal D ₂ in the controller 10
It is supplied to.

Further, the power plant 1 is provided with a rotation sensor 13 for generating and outputting a rotation synchronizing signal x synchronized with the rotation of the crankshaft of the engine 1A. If the engine 1A is, for example, an in-line 4-cylinder engine, the rotation sensor 13 has a crankshaft of 1 because the main component of the muffled noise generated in the passenger compartment 8 is the secondary engine rotation component.
A rotation synchronizing signal x is generated from one pulse every 1/2 rotation and is supplied to the controller 10.

The controller 10 is composed of a necessary interface circuit such as an A / D converter and a D / A converter, a microprocessor, a drive circuit for the exciting coil of the rear engine mount 3D, and the like. Sensor 1
Predetermined arithmetic processing is executed based on the acceleration detection signals D ₁ and D ₂ supplied from Nos. 1 and 12 and the rotation synchronization signal x supplied from the rotation sensor 13 so that the muffled sound in the passenger compartment 8 is reduced. The control signal I is supplied to the rear engine mount 3D.

That is, the controller 10 has a pass band variable filter 15 for extracting the frequency component Bh ₁ (or Bs ₁ ) from the acceleration detection signal D ₁ as shown in FIG. , A variable pass band filter 1 for extracting the frequency component A ₁ from the acceleration detection signal D ₂
6 and filters 15 and 16 based on the rotation synchronization signal x.
And a pass band adjusting unit 17 for adjusting the pass band of the filter 15 and the pass band adjusting unit 17.
The pass band of 6 is adjusted so that the filters 15 and 16 extract the engine rotation secondary component.
In the case of this embodiment, since the rotation synchronizing signal x is synchronized with the engine rotation secondary, the pass band adjusting unit 17
The pass bands of the filters 15 and 16 are adapted to match the frequency of the rotation synchronizing signal x.

Incidentally, here, the rear engine mount 3
When the support rigidity of D is high, the output of the filter 15 is set as the frequency component Bh ₁ , and the rear engine mount 3D
The output of the filter 15 in the case where the support rigidity of is low is defined as the frequency component Bs ₁ . Further, the output of the filter 15 is input to the estimation unit 18, and in the estimation unit 18, the input frequency component Bh ₁ (or B
The frequency component Bs ₁ (or Bh ₁ ) is estimated based on s ₁ ). That is, when the rear engine mount 3D at this time has high rigidity and the frequency component Bh ₁ is supplied from the filter 15, the frequency that would have been calculated if the rear engine mount 3D had low rigidity. The component Bs ₁ is estimated, and conversely, when the frequency component Bs ₁ is supplied from the filter 15 because the rear engine mount 3D at this time has low rigidity, and the rear engine mount 3D has high rigidity. The frequency component Bh ₁ that would have been calculated in Eq. This estimation calculation is performed, for example, from frequency component Bh ₁ to frequency component B
The estimation of s ₁ can be performed by multiplying the frequency component Bh ₁ by the ratio of the dynamic spring constant when the rear engine mount 3D has high rigidity and when the rear engine mount 3D has low rigidity.

Further, the controller 10 includes a transfer function filter 19 which is a filter that models the transfer function between the vibration at the fixed position of the acceleration sensor 11 and the muffled sound in the passenger compartment 8, and the fixed position of the acceleration sensor 12. And a transfer function filter 20, which is a filter that models the transfer function between the vibration of the vehicle and the muffled sound in the vehicle interior 8, and the transfer function filter 19 has a frequency component B that is the output of the filter 15.
h ₁ (or Bs ₁ ) and the frequency component Bs ₁ (or Bh ₁ ) that is the output of the estimation unit 18 are input, and the frequency component A ₁ that is the output of the filter 16 is input to the transfer function filter 20. It has become. The transfer function filter 19 outputs the estimated muffled sounds Bh ₂ and Bs ₂ , and the transfer function filter 20 outputs the estimated muffled sound A ₂ . In addition, here, the rear engine mount 3
Support rigidity of D of the output of the transfer function filter 18 and the estimated muffled sound Bh ₂ in the case of high rigidity, estimates muffled sound output of the transfer function filter 18 when the support rigidity of the rear engine mount 3D is a low rigidity Bs ₂ I am trying.

That is, since the transfer function filters 18 and 19 are filters modeling the transfer function of the system as described above, the estimated muffled sound Bh ₂ is the power plant 1
The muffled sound generated in the vehicle interior 8 due to the vibration that passes through the rear engine mount 3D when the rigidity is high, and the estimated muffled sound Bs ₂ is generated in the power plant 1. Of the generated vibrations, the muffled sound generated in the vehicle interior 8 due to the vibration passing through the rear engine mount 3D when the rigidity is low is shown.
Of the vibrations generated in the power plant 1, ₂ indicates a muffled noise generated in the vehicle interior 8 due to the vibration passing through the right engine mount 3A.

The estimated muffled sound Bh ₂ or Bs ₂ and the estimated muffled sound A ₂ are input to the control signal determining section 21. The control signal determination unit 21 determines whether the support rigidity of the rear engine mount 3D is high rigidity or low rigidity based on the supplied estimated muffled sounds Bh ₂ , Bs _2, and A ₂ in the vehicle interior 8. It is configured to determine whether or not the muffled sound is reduced and output the control signal I or stop the output of the control signal I according to the determination result.

Specifically, the control signal determining section 21
The vector sum "A ₂ + Bh _2" putative muffled sound A ₂ and estimation muffled sound Bh _2, the estimated muffled sound A ₂ and estimation muffled sound Bs ₂ obtains a vector sum "A ₂ + Bs _2", their vector sum Judgment of magnitude relation, vector sum “A ₂
When + Bh ₂ ″ is smaller, it is considered that it is more advantageous to reduce the muffled sound by making the rear engine mount 3D highly rigid, and the control signal I is output while the vector sum “A ₂ + Bs ₂ ” is output. When it is smaller, it is considered that it is more advantageous to reduce the muffled sound when the rear engine mount 3D has low rigidity, and the output of the control signal I is stopped.

FIG. 3 is a flow chart showing the outline of the processing executed in the controller 10. The operation of this embodiment will be described below with reference to FIG. That is, in the power plant 1, vibration that is synchronized with the combustion timing of the engine 1A being driven is generated, and a major part of the vibration is transmitted to the vehicle body 2A via the right engine mount 3A, and the vehicle body 2
Propagate through A and reach the floor lower surface of the passenger compartment 8. The other main part of the vibration of the power plant 1 is transmitted to the rear end portion of the center member 5 via the rear engine mount 3D, is transmitted from there to the vehicle body 2A, and is transmitted through the vehicle body 2A. Reach the bottom of the floor of chamber 8. In this way, the vibration generated in the power plant 1 reaches the floor lower surface of the vehicle compartment 8 via various routes and vibrates the floor surface to generate a muffled sound in the vehicle compartment 8.

Among the vibrations propagating through these paths, the vibration transmitted from the power plant 1 to the vehicle body 2A via the right engine mount 3A is detected by the acceleration sensor 12, and this is detected by the acceleration detection signal D ₂
Is supplied to the controller 10 as the power plant 1
The vibration transmitted from the vehicle body 2A to the vehicle body 2A via the rear engine mount 3D and the sub-frame 6 is detected by the acceleration sensor 11 and is supplied to the controller 10 as an acceleration detection signal D ₁ . Further, the rotation synchronization signal x is supplied to the controller 10 in synchronization with the rotation of the crankshaft of the engine 1A.

In the controller 10, when the signals D ₁ , D ₂ and x are supplied, the processing shown in FIG. 3 is executed. First, in step 101, the rotation synchronization, which is a pulse signal supplied one after another, is performed. The frequency f _{n of the} secondary engine rotation component is calculated based on, for example, the input interval of the signal x. Then, the process proceeds to step 102 and step 1
A filter (a filter corresponding to the filters 15 and 16 in FIG. 2) having the pass band of the frequency f _n calculated in 01 is set, and the acceleration detection signals D ₁ and D ₂ are set by the filter.
By filtering each of the frequency components Bh ₁ (or Bs ₁ ) which is the secondary engine rotation component included in the acceleration detection signal D ₁ and the frequency which is the secondary engine rotation component included in the acceleration detection signal D _2. Extract component A ₁ and.

Next, the routine proceeds to step 103, where the frequency component Bh ₁ (or Bs ₁ ) is, for example, the ratio of the dynamic spring constants (or its reciprocal) when the rear engine mount 3D has high rigidity and low rigidity. The frequency component Bs ₁ (or Bh ₁ ) is estimated and calculated by multiplying by. Then, the process proceeds to step 104, where each frequency component Bh ₁ , Bs ₁ and A
_The estimated muffled sounds Bh ₂ , Bs _2, and A ₂ are calculated by processing ₁ with a filter (filters corresponding to the transfer function filters 19 and 20 in FIG. 2).

Next, in step 105, the phase difference between the estimated muffled sound Bh ₂ and the estimated muffled sound A _{2 and} the phase difference between the estimated muffled sound Bs ₂ and the estimated muffled sound A ₂ are calculated. In addition, when the estimated muffled sounds Bh ₂ and Bs ₂ can be regarded as in-phase, such as when the phase of the vibration passing through the rear engine mount 3D does not change or hardly changes even when the support rigidity of the rear engine mount 3D changes. , This step 105
Then, it suffices to calculate either one of the phase differences.

Next, the routine proceeds to step 106, where the estimated muffled sounds Bh ₂ , Bs ₂ and A ₂ are loud, and step 1
Based on the phase difference obtained in 05, the vector sum “A ₂ + Bh ₂ ” of the estimated muffled sound A ₂ and the estimated muffled sound Bh ₂
And the vector sum “A ₂ + Bs ₂ ” of the estimated muffled sound A ₂ and the estimated muffled sound Bs ₂ are calculated by complex operation. Then, the process proceeds to step 107, and the vector sum “A ₂ + B
It is determined whether or not the magnitude of h ₂ ″ (the amplitude of the vector, the vector absolute value) is smaller than the magnitude of the vector sum “A ₂ + Bs ₂ ”. If the determination is “YES”, the process proceeds to step 108. After shifting to a state in which the control signal I is output to the rear engine mount 3D, the processing of FIG. 3 this time is ended. However, the determination in step 107 is “NO”.
In this case, the process proceeds to step 109 and the output of the control signal I is stopped, and then the process of FIG. 3 this time is ended.

When such processing is executed in the controller 10, if the magnitude relation of the vector sum is "A ₂ + Bh ₂ > A ₂ + Bs ₂ ", as shown in FIG. 4A, for example, Since the process proceeds from step 107 to step 109 and the output of the control signal I is stopped,
The support rigidity of the rear engine mount 3D becomes low,
In the passenger compartment 8, the smaller vector sum "A ₂ + Bs ₂ "
A muffled sound corresponding to will be generated. On the other hand, for example, as shown in FIG. 4B, when the magnitude relation of the vector sum is “A ₂ + Bh ₂ <A ₂ + Bs ₂ ”, the process proceeds from step 107 to step 108 and the control signal I Is output, the support rigidity of the rear engine mount 3D becomes high, and a muffled sound corresponding to the smaller vector sum "A ₂ + Bh ₂ " is generated in the passenger compartment 8 as well. Become.

That is, in the present embodiment, there are vibrations passing through when the rear engine mount 3D has high rigidity and vibrations passing through when the rear engine mount 3D has low rigidity. The support rigidity of the rear engine mount 3D is not controlled based on the magnitude relationship of the rear engine mount 3D, but the rear engine mount 3D is supported based on the magnitude relationship of the vector sum substantially corresponding to the level of the muffled sound in the vehicle interior 8. It controls the rigidity. Therefore, the muffled sound can be effectively reduced.

For example, in the case shown in FIG. 4 (b),
Since the estimated muffled sound Bs ₂ is smaller than the estimated muffled sound Bh ₂ , the rear engine mount 3 has a simple control.
It is desirable that the support rigidity of D is low, so that low rigidity is selected, and the muffled sound in the passenger compartment 8 corresponds to the vector sum “A ₂ + Bs ₂ ”, resulting in high rigidity. Although a muffled sound larger than the vector sum “A ₂ + Bh ₂ ” when selected is generated, in the present embodiment, high rigidity is selected even in such a case,
The level of the muffled sound that is generated can be suppressed to a low level.

Here, in this embodiment, the rear engine mount 3D corresponds to the rigidity variable element (one rigidity variable element), and the right engine mount 3A is a coupling element or a support other than the one rigidity variable element. Accelerometer 1 corresponding to the element
1 corresponds to the first vibration detecting means, the acceleration sensor 12 corresponds to the second vibration detecting means, and by the processing of the rotation sensor 13, the filter 15, the pass band adjusting section 17, the estimating section 18, and steps 101 to 103. The first extracting means is configured and includes the rotation sensor 13, the filter 16, and the pass band adjusting unit 1.
7 and the processing of steps 101 and 102 constitute the second extracting means, the transfer function filter 19 and the processing of step 104 constitute the first estimating means, and the transfer function filter 20 and the processing of step 104 constitute the second extracting means. The estimation means is configured, and the rigidity control means is configured by the control signal determination unit 21 and the processes of steps 105 to 109.

5 to 7 are views showing a second embodiment of the present invention. First, the structure of the present embodiment will be described with reference to FIG. 5, which is a schematic plan view of the vehicle 2. However, the same components as those in the first embodiment are designated by the same reference numerals, and the duplicated description will be omitted. That is, in the present embodiment, the rear engine mount 3D has a fixed support rigidity like the other engine mounts 3A to 3C, whereas the sub-frame 6
, 7 interposed between the vehicle and the vehicle body 2A
The support rigidity of is changed according to the control signal I. The specific configuration for varying the support rigidity of the insulators 7, ..., 7 may be the same as, for example, the rear engine mount 3D described in the first embodiment, or The above-mentioned Japanese Patent Laid-Open No. 5-2 proposed above
As disclosed in FIG. 2 of Japanese Unexamined Patent Publication No. 13039, an elastic body that is interposed between the subframe 6 and the vehicle body 2A to form two fluid chambers, and an orifice that communicates between the two fluid chambers, It is also possible to include the electro-viscous variable fluid enclosed in the two fluid chambers and the orifice and the electrode plate for applying a voltage to the electro-viscous variable fluid in the orifice. If the control signal I as the control current is not supplied to the plate, the viscosity of the electrorheological variable fluid in the orifice remains low, the supporting rigidity of the insulators 7, ..., 7 becomes low, and the control signal I is supplied. If so, the viscosity of the electroviscous variable fluid in the orifice becomes high, and the support rigidity of the insulators 7, ..., 7 becomes high.

The configuration other than this is the same as that of the first embodiment, the functional configuration of the controller 10 is the same as that of FIG. 2 of the first embodiment, and the processing procedure executed in the controller 10 is the same as that of the first embodiment. This is similar to FIG. 3 of the first embodiment. With such a configuration, the acceleration sensor 11 detects the vibration generated in the power plant 1 and transmitted to the vehicle body 2A via each of the insulators 7, ... By performing the same process, the same effect can be obtained.

When the support rigidity of the insulators 7, ..., 7 is changed from low rigidity to high rigidity, the sub-frame 6
The force transmissibility between the vehicle and the vehicle body 2A is as shown in FIG. 6 for high rigidity (H) and low rigidity (S), respectively.
A region in which the amplitude of the force transmissibility due to the bounce resonance of the subframe 6 is 1 or more moves to the high frequency side, and the phase also changes. Therefore, in the controller 10, the frequency component Bh
₁ (or Bs ₁ ) to frequency component Bs ₁ (or Bh ₁ )
When estimating the above, it is necessary to consider not only the amplitude ratio (dynamic spring constant ratio) considered in the first embodiment but also the phase difference. Particularly, as can be seen from FIG. 6, the amplitude ratio depends on the frequency. It is necessary to keep in mind that the phase difference also greatly differs.

By switching the support rigidity of the insulators 7, ..., 7 between high rigidity and low rigidity,
The fact that the vibrations passing through the insulators 7, ..., 7 have a phase difference means that there is a phase difference between the estimated muffled sounds Bh ₂ and Bs ₂ as shown in FIGS. 7A and 7B, for example. That's what it means. Therefore, those estimated muffled sounds B
If the control for simply determining the support rigidity of the insulators 7, ..., 7 is executed based only on the magnitudes of h ₂ and Bs _2, the muffled noise cannot be effectively reduced. By the way, in any of the examples of FIGS. 7A and 7B, if the smaller one of the estimated muffled sounds Bh ₂ and Bs ₂ is selected, the one having the larger vector sum is selected. Become.

However, with the configuration of this embodiment, the same effect as that of the first embodiment can be obtained. Therefore, if the smaller vector sum is surely selected, the level of the muffled sound generated is suppressed to a low level. It is possible. Here, in this embodiment, each insulator 7, ..., 7 corresponds to a variable stiffness element.

8 to 11 are views showing a third embodiment of the present invention. First, the structure of the present embodiment will be described with reference to FIG. 8 which is a schematic plan view of the vehicle 2. However, the same components as those in the first embodiment are designated by the same reference numerals, and the duplicated description will be omitted. That is, in the present embodiment, the acceleration sensor 12 is replaced by a microphone 14 for detecting the noise in the passenger compartment 8 at the sound pressure level, and the detection result of the microphone 14 is used as the noise detection signal E by the controller. 1
It is supplied to 0.

Then, the controller 1 in this embodiment
The noise detection signal E is input to the filter 16 as shown in FIG. Therefore, the noise detection signal E is output from the filter 16.
The engine rotation secondary component included in is output as the frequency component E ₁ . Further, the controller 10 has a vector difference H (= E) between the frequency component E ₁ and the estimated muffled sound Bh ₂ (or Bs ₂ ) output from the transfer function filter 19.
_1- Bh ₂ or E ₁ -Bs ₂ )
Is provided, and the vector difference H calculated by the difference calculation unit 22 is supplied to the control signal determination unit 21. In addition, in the difference calculation part 22, when the support rigidity of the rear side engine mount 3D is high rigidity at present,
The vector difference H is calculated as H = E ₁ −Bh ₂ (1), and the rear engine mount 3 at the present time is calculated.
When the support rigidity of D is low, the vector difference H is calculated as H = E ₁ -Bs ₂ (2).

Then, even in the control signal determining section 21 of the present embodiment, the estimated muffled sounds Bh ₂ and Bs ₂ supplied,
Based on the vector difference H, it is determined whether the support rigidity of the rear engine mount 3D is high rigidity or low rigidity to reduce the muffled sound in the vehicle interior 8, and the judgment result is determined according to the judgment result. To output the control signal I or the control signal I
The control to stop the output of is executed.

Specifically, the control signal determining section 21
The vector sum of the vector difference H and the estimated muffled sound Bh ₂ "H
+ Bh ₂ ”, and the vector sum“ H + Bs ₂ ”of the vector difference H and the estimated muffled sound Bs ₂ is obtained, and the magnitude relation of the vector sums is determined, and when the vector sum“ H + Bh ₂ ”is smaller, , I think that it is more advantageous to reduce the muffled noise when the rear engine mount 3D has high rigidity,
Control signal I is output, while vector sum "H + Bs ₂ "
When it is smaller, it is considered that it is more advantageous to reduce the muffled sound when the rear engine mount 3D has low rigidity, and the output of the control signal I is stopped.

The other structure is the same as that of the first embodiment. FIG. 10 is a flow chart showing the outline of the processing executed in the controller 10 of the present embodiment, and the operation of the present embodiment will be described below with reference to FIG. First, in step 201, the frequency f _n of the engine rotation secondary component is calculated as in step 101 of FIG. Next, in step 202, a filter having a pass band of frequency f _n is set, the acceleration detection signal D ₁ is filtered by the filter, and the frequency component Bh ₁ (or B
s ₁ ) is extracted.

Next, in step 203, the noise detection signal E is processed by a filter similar to the filter used in step 202, so that the frequency component E, which is the secondary engine rotation component, included in the noise detection signal E. Extract ₁ . Next, in step 204, the frequency component Bs ₁ (or Bh ₁ ) is estimated in the same manner as in step 103 of FIG. 3, and then the process proceeds to step 205, in which the estimated muffled sound Bh ₂ is calculated as in step 104 of FIG. And Bs ₂ are calculated.

Then, the routine proceeds to step 206, where the vector difference H is calculated according to the above equation (1) or equation (2). That is, since the vector difference H is calculated according to the above formula (1) or formula (2), the muffled sound due to the vibration passing through the rear engine mount 3D is subtracted from the muffled sound in the vehicle interior 8. Equivalent to. Then step 2
In step 07, the phase difference between the estimated muffled sound Bh ₂ and the vector difference H and the phase difference between the estimated muffled sound Bs ₂ and the vector difference H are calculated.

[0063] Then, the process proceeds to step 208, the vector sum of the vector difference H and estimated muffled sound Bh ₂ "H + Bh
₂ ”and the vector difference H and the vector sum“ H + Bs ₂ ”of the estimated muffled sound Bs ₂ are calculated by a complex operation, and then the process proceeds to step 209, where the magnitude of the vector sum“ H + Bh ₂ ”is the vector sum“ H + Bs _{2 ”.} It is determined whether or not it is smaller than the size of ", and when this determination is" YES ",
On the other hand, the control signal I is output to the rear engine mount 3D at step 210, and when the determination is "NO", the control signal I is stopped at step 211. State.

When such processing is executed, as shown in FIG. 11A, which illustrates the relationship between the vectors when the rear engine mount 3D has high rigidity, the magnitude relationship of the vector sum is "H + Bh". _{When 2} > H + Bs ₂ ″, the output of the control signal I is stopped and the support rigidity of the rear engine mount 3D becomes low, and in the passenger compartment 8, the smaller vector sum “H + Bs ₂ ” is supported. A muffled sound is generated. On the other hand, for example, FIG.
As shown in, the magnitude relation of the vector sum is “H + Bh ₂ <
In the case of H + Bs ₂ ″, the control signal I is output,
The support rigidity of the rear engine mount 3D is high,
In the passenger compartment 8, the smaller vector sum “H + Bh”
A muffled sound corresponding to ₂ ”will be generated.

That is, also in this embodiment, similarly to the first embodiment, the rear engine mount 3D is supported based on the magnitude relation of the vector sum substantially corresponding to the level of the muffled sound in the passenger compartment 8. Since the rigidity is controlled, the muffled noise can be effectively reduced. Moreover, in the first or second embodiment, since the acceleration sensors 11 and 12 are used, there is no particular problem if the main path of the vibration that causes the muffled sound is known, but the vibration does not occur. There are many routes, and if the main route cannot be specified from among them, a large number of acceleration sensors will be required, and the computation load will increase accordingly. Therefore, a computation processor capable of high-speed processing is required.

On the other hand, in the present embodiment, the vector difference H corresponds to the muffled sound in the passenger compartment 8 minus the muffled sound caused by the vibration passing through the rear engine mount 3D. , The muffled sound caused by the vibrations passing through the engine mounts 3A to 3B other than the rear engine mount 3D is naturally vibrations passing through all the other paths (for example, vibrations propagating in the air or a support bracket for an exhaust pipe). It also includes the muffled sound caused by the vibration transmitted to the vehicle body 2A through the vehicle).

That is, with the configuration of this embodiment, the muffled sound can be effectively reduced even when the main path of the muffled sound vibration cannot be specified. The optimum support rigidity of the rear engine mount 3D includes, for example, the frequency component E ₁ of the noise detection signal E when the support rigidity is high and the noise detection signal E when the support rigidity is low. It is also possible to determine by comparing with the frequency component E _{1 of the above,} and the result equivalent to that of the present embodiment can be obtained by such a method, but with this, if the supporting rigidity is not actually switched, it is optimum. However, there is a drawback that it takes time because the support rigidity is not known. This drawback becomes remarkable especially when the support rigidity can be switched in multiple stages.

However, with the configuration of this embodiment, the optimum supporting rigidity can be obtained without actually changing the supporting rigidity, so that the optimum state can be obtained in a short time. Here, in the third embodiment, the rear engine mount 3D corresponds to the rigidity variable element (one rigidity variable element), the acceleration sensor 11 corresponds to the vibration detecting means, and the microphone 14 corresponds to the noise detecting means. Corresponding to, the rotation sensor 13, the filter 15, the pass band adjusting unit 17, the estimating unit 18 and the processing of steps 201, 202, 204 constitutes the first extracting means, and the rotation sensor 13, the filter 16, the pass band adjusting unit. The second extracting means is constituted by the processing of 17 and step 203, the estimating means is constituted by the processing of the transfer function filter 19 and step 204, and the vector difference calculating means is constituted by the difference calculating section 22 and step 206. Control signal determination unit 21
The rigidity control means is configured by the processing of steps 207 to 211.

12 to 17 are views showing a fourth embodiment of the present invention. First, the structure of the present embodiment will be described with reference to FIG. 12 which is a schematic plan view of the vehicle 2. However, the same components as those in the first embodiment are designated by the same reference numerals, and the duplicated description will be omitted. That is, the configuration of the present embodiment is basically the same as that of the first embodiment described above, except that the mass member 25 is mounted on the sub-frame 6 via the mounting element with variable support rigidity.
Is mounted, and the supporting rigidity of the mounting element of the mass body 25 is switched according to the control signal J supplied from the controller 10. In addition, as for the configuration in which the support rigidity of the attachment element of the mass body 25 is variable, for example, the configuration of the rear engine mount 3D described in the first embodiment, the configuration of the insulator 7 described in the second embodiment, and the like are used. Applied.

The functional configuration of the controller 10 is as follows.
As shown in FIG. 13, the control signal determination unit 21
Is a control signal I for the rear engine mount 3D,
The control signal J with respect to the attachment element of the mass body 25 is controlled to be output or stopped. Here, the subframe 6 in this embodiment is represented by a model as shown in FIG. However, M
Is the mass of the sub-frame 6, K is the spring constant of the insulator 7, C is the damping coefficient of the insulator 7, m _d is the mass of the mass 25, k _d is the spring constant of the mounting element of the mass 25,
c _d is the attenuation coefficient of the mounting element of the mass 25. Then, P ₀ the vibration force of the sub-frame 6, the input to the vehicle body 2 and P _1, the force transmission ratio between their P ₀ and P ₁ (P ₁
/ P ₀ ) is given by the following expression (3), where S is the Laplace operator.

P ₁ (S) / P ₀ (S) = {(m _d S ² + c _d S + k _d ) (CS + K)} / {{MS ² + (C + c _d ) S + (K + k _d )} (m _d S ^{_{2 + c d S + k d}} ) - (c d S + k d) 2} ...... (3) in this equation (3) derived is as follows. That is,
In the model shown in FIG. 14, when the displacement of the subframe 6 is x ₀ and the displacement of the mass body 25 is x _d , the following differential equation is established.

[0072] _{^{M · d 2 x 0 / dt}} 2 + C · dx 0 / dt + K · x 0 + c d (dx 0 / dt-dx d / dt) + k d (x 0 -x d) = P 0 (t) ... _{... (4) m d · d} 2 x d / dt 2 + c d (dx d / dt-dx 0 / dt) + K (x d -x 0) = 0 ...... (5) thereof (4) and (5 ) When the formula is Laplace transformed and rearranged, the following formula is obtained.

{MS²+ (C + c_d) S + K + k_d} X₀(S)-(c_dS + k_d) X_d(S) = P₀(S) …… (6) (m_dS²+ C_dS + k_d) X_d(S)-(c_dS + k_d) X₀(S) = 0 (7) From this equation (7), x_d(S) = x₀(S) (c_d+ K_d) / (M_dS²+ C_dS + k_d) ... (8) is obtained, and the above equation (6) is substituted into this equation (8) for rearranging.
If you do, x₀(S) / P₀(S) = (m_dS²+ C_dS + k_d) / {{MS²+ (C + c_d) S + K + k_d} (M_dS²+ C_dS + k_d)-(C_dS + k_d)²} (9), and from this equation (9), the force transmission factor (P₁(S) / P₀
(S) = (CS + K) x ₀(S))
Expression (3) is obtained.

In the system represented by the above equation (3), when the resonance frequency of the sub-frame 6 and the resonance frequency of the mass body 25 substantially match (for example, K / M≈k _d / m).
_In the case of _d ), the mass body 25 functions as a known dynamic vibration absorber, and its characteristics are as shown in FIG. On the other hand, when the resonance frequency of the sub-frame 6 and the resonance frequency of the mass body 25 are significantly deviated,
As shown in FIG. 16, the mass 25 functions to invert the phase of force transmission at a certain frequency.

That is, in the structure of the present embodiment, the controller 10 supplies or stops the supply of the control signal J to the mounting element of the mass body 25 as appropriate, so that the vehicle body 2A via the subframe 6 can be controlled. It is possible to reverse the phase of the vibration transmitted to. As a result, in addition to the estimated muffled sound “Bh ₂ ” when the support rigidity of the rear engine mount 3D is high and the estimated muffled sound “Bs ₂ ” when it is low rigidity, their phases estimation booming noise by inverting the "-Bh _2", - it is possible to also select a "Bs _2".

Therefore, in the control signal determining section 21 of the controller 10, the four estimated muffled sounds Bh that can be selected are selected.
₂ , Bs ₂ , -Bh ₂ , -Bs ₂ and estimated muffled sound A ₂
And the respective vector sums “A ₂ + Bh ₂ ”, “A ₂ +
Bs ₂ ”,“ A ₂ -Bh ₂ ”, and“ A ₂ -Bs ₂ ”are calculated, the minimum vector sum among them is calculated, and a muffler sound corresponding to the minimum vector sum is generated. In addition, the control signal I and the control signal J are appropriately output or stopped.

[0077] For example, when the estimated muffled sound _{Bh 2 ~-Bs 2, A} 2 , as shown in FIG. 17 is obtained, since the vector sum "A ₂ -Bs _2" is the smallest vector sum, estimated Whether or not to output the control signal I and the control signal J is determined so that the muffled sound "-Bs ₂ " is generated. In particular,
The output of the control signal I is stopped so that the support rigidity of the rear engine mount 3D becomes low, and the resonance of the subframe 6 is reversed so that the phase of force transmission between the subframe 6 and the vehicle body 2A is reversed. The control signal J is output so that the frequency and the resonance frequency of the mass body 25 are significantly different from each other.

As described above, according to the configuration of this embodiment, the muffled sound can be effectively reduced, and the phase inversion of the vibration via the sub-frame 6 can be independently performed. Since it can be performed, the number of selectable states is increased, and the degree of freedom of control is larger than that in the first embodiment,
The advantage that the muffled sound can be reduced more effectively is obtained.

18 and 19 are diagrams showing a fifth embodiment of the present invention. First, the configuration of the present embodiment will be described with reference to FIG. 12, which is a schematic plan view of the vehicle 2. However, the same components as those in the above-described respective embodiments are designated by the same reference numerals, and the duplicate description thereof will be omitted. That is, the configuration of this embodiment is basically the same as that of the second embodiment, except that a vehicle speed sensor 26 for detecting the vehicle speed based on the rotation speed of the output shaft of the transmission 1B is provided. Yes, the vehicle speed sensor 26
Is output to the controller 10 as a vehicle speed detection signal V.

The controller 10 of this embodiment also executes the muffled sound reduction control shown in FIG. 3 of the first embodiment, but in this embodiment, before the muffled sound reduction control, The control shown in 19 is executed. That is, when the process of FIG. 19 is started, first, in step 301, the rotation synchronizing signal x and the vehicle speed detection signal V are read, then the process proceeds to step 302, and the engine is determined based on, for example, the input interval of the rotation synchronizing signal x. The rotation speed N is calculated.

Then, the routine proceeds to step 303, where it is judged if the engine speed N is smaller than a predetermined speed N _cr . The predetermined rotation speed N _cr is a rotation speed at a boundary between a low frequency region where the muffled sound reduction control effectively functions and a middle and high frequency region where it is difficult to effectively function. When the determination in step 303 is “YES”, the process proceeds to step 304, and it is determined whether the vehicle speed detection signal V is smaller than the predetermined vehicle speed V _cr . The predetermined vehicle speed V _cr is a vehicle speed that is a boundary between a low vehicle speed at which the vibration input from the road surface is not so large and a medium or high vehicle speed at which the vibration input from the road surface becomes large.

The determination in step 304 is also "YE
In the case of “S”, the process proceeds to step 305, and the muffled sound reduction control shown in FIG. 3 is executed. However, step 30
3, the determination of at least one of step 304 is “NO”
When it becomes, the process proceeds to step 306, the output of the control signal I is stopped, and the muffled sound reduction control is not executed.

When such processing is executed, the muffled sound can be effectively reduced, and when the vibration input from the road surface is not excessive, the muffled sound reduction control shown in FIG. 3 is executed. Therefore, the muffled sound is effectively reduced. However, when the muffled sound cannot be effectively reduced or when the vibration input from the road surface is excessive, the output of the control signal I is stopped, so that the subframe 6 and the vehicle body 2A are not connected to each other. The rigidity of the coupled insulators 7, ..., 7 becomes low, and the vibration input from the power plant 1 to the sub-frame 6 and the front wheel 4FL from the road surface,
The vibration input transmitted to the sub-frame 6 via the 4FR and the suspension is preferentially exerted the function of being isolated by the insulators 7, ..., 7 so that more efficient control can be executed.

That is, the configuration of this embodiment has an advantage that both suppression of muffled noise and reduction of vibration input from the power plant 1 and the road surface can be achieved.
The calculation load of the controller 10 and the load on the insulators 7, ..., 7 can be reduced. Here, in the present embodiment, the rotation sensor 13 and the processing of step 302 constitute a rotation speed detecting means, and the vehicle speed sensor 26 corresponds to the vehicle speed detecting means.

In the fifth embodiment, the suction negative pressure sensor as the suction negative pressure detecting means for detecting the suction negative pressure of the power plant 1 is provided, and the controller 1 is also provided.
At 0, the process _proceeds to step 305 only when the engine speed N is equal to or lower than the predetermined speed N _cr and the suction negative pressure exceeds the predetermined pressure (a value at which the engine load can be determined to be a high load). It is also possible to execute the muffled sound reduction control, and with such a configuration, the muffled sound reduction control is executed in a situation where the muffled noise is likely to occur due to low engine speed and high engine load, and other than that situation. Then, the anti-vibration function by the subframe will be given priority,
The calculation load of the controller 10 and the load on the insulators 7, ..., 7 can be further reduced.

Further, in each of the above embodiments, the rear engine mount 3D as the variable rigidity element, the insulator 7,
The supporting rigidity of 7 ... can be switched in two steps. For example, the supporting rigidity may be switched in three steps or more. The more switching steps are performed, the more detailed control can be performed, and the more efficient the muffler operation is. The sound can be reduced.

The variable rigidity element is not limited to the rear engine mount 3D and the insulators 7, ..., 7, and if the main path of vibration transmission includes, for example, the other engine mounts 3A to 3C. The engine mount may be a variable rigidity element, or all the engine mounts 3A to 3D may be variable rigidity elements, and some of the engine mounts 3A to 3D may be considered as one variable rigidity element, and other engine The mount may be considered as a coupling element or a supporting element other than one variable stiffness element to perform control. If the number of variable stiffness elements is increased in this way, finer control can be performed, resulting in higher efficiency. The muffled sound can be reduced.

Further, the rear engine mount 3D as the variable rigidity element, the insulators 7, ..., 7 and the mass body 2 are provided.
The configuration in which the supporting rigidity of the mounting element of 5 is variable is not limited to the configuration described in the above embodiment,
Other configurations may be used as long as the support rigidity is variable and can be externally controlled according to a control signal or the like. Further, in each of the above-described embodiments, the case where the present invention is applied to the FF vehicle of the engine horizontal type is described, but the vehicle to which the present invention is applicable is not limited to this, and FR
It may be a vehicle. The engine 1A is not limited to the in-line four-cylinder type, but may be another type of engine such as an in-line six-cylinder type.
However, if the engine type changes, the engine rotation order component that greatly affects the muffled sound also changes, so the frequency bands extracted by the filters 15 and 16 must be changed accordingly.

[0089]

As described above, according to the first aspect of the present invention, the rigidity control means estimates the support rigidity of the variable stiffness element by the first estimation means for estimating the vehicle interior noise and the second estimation. Since the vector sum with the vehicle interior noise estimated by the means is controlled to be the minimum, the muffled noise can be effectively reduced.

According to the second aspect of the present invention, the rigidity control means calculates the support rigidity of the variable rigidity element as a vector of the vehicle interior noise estimated by the estimation means and the vector difference calculated by the vector difference calculation means. Since the sum is controlled to be the minimum, the muffled sound can be effectively reduced even when the main path of the muffled sound vibration cannot be specified.

According to the third aspect of the invention, since the phase inversion of the vibration via the subframe can be independently performed, the number of selectable states is increased, so that the degree of freedom of control is increased and the muffled There is an effect that the sound can be reduced more effectively. Further, according to the invention of claim 4, since the supporting rigidity of the variable rigidity element is maintained in a low state in a situation where the muffled noise cannot be effectively reduced, the rigidity of the coupling element for coupling between the subframe and the vehicle body is improved. There is also an effect that the function in which the vibration input from the power plant to the sub-frame is damped by the coupling element is exerted preferentially by being lowered, and more efficient control is executed.

According to the fifth aspect of the present invention, since the supporting rigidity of the variable stiffness element is maintained in a low state in the case where the vibration input from the road surface is excessive, the load transmitted from the road surface to the sub-frame is added. There is also an effect that the function of preventing vibration input by the coupling element is exerted preferentially, and more efficient control is executed. According to the sixth aspect of the invention, the muffled sound reduction control is executed in a situation where the engine is at a low rotation speed and the engine is under a high load, and muffled noise is likely to occur. Since the function will be prioritized,
There is also an effect that extremely efficient control is executed.

[Brief description of drawings]

FIG. 1 is a schematic plan view of a vehicle in a first embodiment.

FIG. 2 is a block diagram showing a functional configuration of a controller according to the first embodiment.

FIG. 3 is a flowchart showing an outline of processing executed in the controller of the first embodiment.

FIG. 4 is an explanatory diagram of an operation in the first embodiment.

FIG. 5 is a schematic plan view of a vehicle in the second embodiment.

FIG. 6 is a frequency characteristic diagram of a force transmissibility between a subframe and a vehicle body.

FIG. 7 is an explanatory diagram of an operation in the second embodiment.

FIG. 8 is a schematic plan view of a vehicle in the third embodiment.

FIG. 9 is a block diagram showing a functional configuration of a controller according to a third embodiment.

FIG. 10 is a flowchart showing an outline of processing executed in the controller of the third embodiment.

FIG. 11 is an explanatory diagram of an operation in the third embodiment.

FIG. 12 is a schematic plan view of a vehicle in a fourth embodiment.

FIG. 13 is a block diagram showing a functional configuration of a controller according to a fourth embodiment.

FIG. 14 is a model diagram of a subframe.

FIG. 15 is a frequency characteristic diagram of a force transmissibility between a subframe and a vehicle body.

FIG. 16 is a frequency characteristic diagram of force transmissibility between the subframe and the vehicle body.

FIG. 17 is an explanatory diagram of an operation in the fourth embodiment.

FIG. 18 is a schematic plan view of a vehicle in the fifth embodiment.

FIG. 19 is a flowchart showing an outline of processing executed in the controller of the fifth embodiment.

FIG. 20 is a schematic plan view of a vehicle illustrating a conventional power plant supporting device.

FIG. 21 is a frequency characteristic diagram of force transmissibility between the subframe and the vehicle body.

FIG. 22 is a frequency characteristic diagram of a radiation coefficient.

FIG. 23 is a characteristic diagram showing the relationship between support rigidity and noise level.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 power plant 1A engine 1B transmission 2 vehicle 2A vehicle body 3A-3D engine mount (support element) 6 subframe 7 insulator (coupling element) 8 vehicle compartment 10 controller 11 acceleration sensor (first vibration detection means, vibration detection means) 12 Acceleration sensor (second vibration detection means) 13 Rotation sensor 14 Microphone (noise detection means) 15 Filter (first extraction means, extraction means) 16 Filter (second extraction means) 19 Transfer function filter (first estimation) Means and estimation means) 20 Transfer function filter (second estimation means) 21 Control signal determination section (rigidity control means) 22 Difference calculation section (vector difference calculation means) 25 Mass body

Claims (6)

[Claims] 1. A sub-frame coupled to a vehicle body via at least one coupling element, at least between a power plant of a vehicle including an engine and the vehicle body, and between the power plant and the sub-frame. In a power plant supporting device including a plurality of supporting elements interposed one by one, at least one element of the coupling element or each element included in the supporting element is a stiffness variable element with variable support stiffness, and A first vibration detecting means for detecting a vibration passing through the one variable rigidity element, and a first extracting means for extracting a predetermined order component of engine rotation from the vibration detected by the first vibration detecting means, Second vibration detection means for detecting vibrations passing through the coupling element or the support element other than the one stiffness variable element, and the second vibration detection A first estimating means for estimating a second extraction means for extracting a predetermined order components of engine speed from vibration stage detects, interior noise caused by the first extracting means extracts the component,
Second estimating means for estimating vehicle interior noise caused by the components extracted by the second extracting means, vehicle interior noise estimated by the first estimating means, and vehicle interior estimating by the second estimating means A power plant supporting device, comprising: rigidity control means for controlling the supporting rigidity of the variable rigidity element so that the vector sum with noise is minimized. 2. A sub-frame coupled to a vehicle body through at least one coupling element, at least between a power plant of a vehicle including an engine and the vehicle body, and between the power plant and the sub-frame. In a power plant supporting device including a plurality of supporting elements interposed one by one, at least one element of the coupling element or each element included in the supporting element is a stiffness variable element with variable support stiffness, and A first vibration detecting means for detecting a vibration passing through the variable stiffness element, and a first order component for extracting engine rotation from the vibration detected by the vibration detecting means
And a noise detection means for detecting vehicle interior noise,
Second extracting means for extracting a predetermined order component of engine rotation from noise detected by the noise detecting means; estimating means for estimating vehicle interior noise caused by the component extracted by the first extracting means; Vector difference calculation means for calculating the vector difference between the component extracted by the second extraction means and the vehicle interior noise estimated by the estimation means, and the vector sum of the vector difference and the vehicle interior noise estimated by the estimation means is the minimum. And a rigidity control means for controlling the supporting rigidity of the variable rigidity element so that the power plant supporting apparatus is provided. 3. A mass body is attached to the sub-frame via a mounting element with variable support rigidity, and the rigidity control means is configured to support the rigidity of the variable rigidity element and the mounting element so that the vector sum is minimized. The power plant supporting apparatus according to claim 1 or 2, which controls the power. 4. At least one of the coupling elements is the variable rigidity element, and rotation speed detection means for detecting an engine rotation speed is provided, and the rigidity control means is configured to set the engine rotation speed to a predetermined value. The power plant support device according to claim 1, wherein the support rigidity of the variable rigidity element included in the coupling element is maintained in a low state when the rotational speed is equal to or higher than the rotational speed. 5. The rigidity variable element is used as at least one of the coupling elements, and vehicle speed detection means for detecting a vehicle speed is provided, and the rigidity control means is provided when the vehicle speed is equal to or higher than a predetermined vehicle speed. The power plant support device according to claim 1, wherein the support rigidity of the variable rigidity element included in the coupling element is maintained in a low state. 6. At least one of the coupling elements is the variable rigidity element, a rotation speed detecting means for detecting an engine rotation speed, and a suction negative pressure detecting means for detecting a suction negative pressure of the power plant. And the rigidity control means, when the engine speed is equal to or higher than a predetermined speed, or the suction negative pressure is equal to or lower than a predetermined pressure, the rigidity control means supports the rigidity of the variable rigidity element included in the coupling element. The power plant supporting device according to any one of claims 1 to 3, which maintains the low level.