JPH0756315B2 - Controlled engine mount - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention encloses an electrorheological fluid whose viscosity is changed according to an applied voltage, and a fluid viscosity in an orifice provided between a main fluid chamber and a sub fluid chamber. Controllable engine mount with variable

2. Description of the Related Art As a control type engine mount of this type, for example, the one disclosed in Japanese Patent Laid-Open No. 60-104828 has heretofore been known,
In such a control type engine mount, a main fluid chamber (upper chamber) formed in a supporting elastic body (vibration-proof elastic body) and a sub-fluid chamber (lower chamber) defined by elastic walls are provided as electrodes. An orifice, that is, an orifice provided with an electrode plate is connected, and an electrorheological fluid as a variable viscosity fluid is enclosed in the main and sub-fluid chambers and the orifice, and the voltage applied to the electrode plate against input vibration is applied. By changing the state, the flow state of the fluid in the orifice is changed, so that the transmission state of vibration can be adjusted appropriately.

However, in such a conventional control type engine mount, vibration transmitted between the vehicle body and the power unit via the engine mount is input through the supporting elastic body itself, When the fluid is moved between the main and sub fluid chambers via the orifice, the phase with the input via the expansion elasticity is 0 ° to 180 due to the dynamic vibration absorber action with the fluid in the orifice as the mass.
It is changed to ゜.

Therefore, a sufficient control effect cannot be obtained unless each state quantity of the vibration system is grasped and controlled accordingly.

For example, in the conventional control type engine mount, control is performed so as to suppress the swing of the power unit as much as possible for an engine shake that appears as a low frequency and large amplitude.

That is, in a solid type (solid rubber body) engine mount that has been generally used in the past, the power unit resonates at around 10HZ and an engine shake occurs, but in a region where the frequency is slightly smaller than this resonance point. Although a region where the vibration transmissivity is significantly reduced appears, a region where the transmissibility is deteriorated appears in a region where the frequency is slightly higher than the resonance point, and the vibration transmission to the vehicle body side is significantly increased.

Therefore, in order to reduce the region where the vibration transmissibility deteriorates,
When the engine mount is a liquid-filled type and the phenomenon in which the liquid of constant viscosity is resonated in the orifice is used to improve the region where the transmissibility is deteriorated, the resonance is caused in the part where the frequency is slightly smaller than the resonance point. As a result, an area in which the transmissibility deteriorates due to an increase in the loss factor appears.

Therefore, in the control type engine mount described above, by changing the fluid viscosity in the orifice,
Although it is possible to improve the deterioration region of the transmissibility due to the increase of the loss factor, the conventional control of the control type engine mount is performed with emphasis on suppressing the displacement of the power unit. The transmissibility at that time has a characteristic that the solid type engine mount and the liquid-filled engine mount are eclectic characteristics before and after the resonance point. There was a problem that it was inferior to the engine mount.

Therefore, the present invention considers the time of input to the vehicle body side as a reference, and in a certain frequency region, the power unit is made capable of vibrating and the power unit is used as the mass of the dynamic vibration absorber, so that the input vibration from the road surface is also adjusted. An object of the present invention is to provide a control type engine mount capable of significantly reducing the input vibration to the vehicle body in the vibration system of the entire vehicle.

In order to achieve the above object, the invention of claim 1 is, as shown in FIG. 1, an elastic body c disposed between a vehicle body a and a power unit b, and an elastic body c. A main fluid chamber d, which is arranged in parallel and whose volume is changed by input vibration, and a sub-fluid chamber f, which communicates with the main fluid chamber d via an electrode orifice e and has a variable volume, are provided. Orifice e
In a control type engine mount in which an electrorheological fluid whose viscosity is changed according to an applied voltage is enclosed and the attenuation rate in the electrode orifice e is changed, a vehicle body motion for detecting a vertical movement of a vehicle body a Detection means g
A fluid movement detecting means h in the orifice for detecting the movement of the fluid in the electrode orifice e, and a fluid in the vehicle body a and the orifice e based on the detection values of the body movement detecting means g and the fluid movement detecting means h in the orifice. The second condition in which the magnitude of the velocity of the fluid in the orifice e is determined based on the predetermined value A.
A third condition for determining the condition and the magnitude of the speed of the vehicle body a based on the predetermined value B is obtained, and the voltage applied to the electrode orifice e is controlled based on these first, second and third conditions. It is configured by providing the control means i.

The invention of claim 2 is the same as the invention of claim 1,
The displacement amount of the vehicle body a is X ₁ , and the displacement amount of the fluid in the orifice e is X ₃
If a, the first condition and X ₃ · _{1 <0,} the second condition | ₃ | a <A, and a third condition _{(X 3 / | X 3 |} ) · 1
Set as> B.

Further, as shown by a broken line in FIG. 1, the invention of claim 3 is, in the invention of claim 1 or 2, provided with unsprung motion detecting means k for detecting the motion of unsprung j of the suspension. The predetermined values A and B are made variable in accordance with the detection value of the downward movement detecting means k.

Furthermore, in the invention of claim 4, in the invention of claim 3, where the unsprung displacement is X ₀ and the gays preset according to the vehicle are K ₁ and K ₂ , the spring within a fixed time the max, a = K ₁ maximum value under acceleration _{(| | 0) (| 0} |) max, B = K 2 (| 0 |) is set as max.

According to the control type engine mount of the invention described in claim 1, the voltage applied to the electrode orifice e is determined by the vehicle body a and the moving direction of the fluid in the orifice. Since the second condition where the magnitude of the speed is determined based on the predetermined value A and the third condition where the magnitude of the vehicle speed is determined based on the predetermined value B are controlled, the state of the engine mount and the vehicle body The vibration state of can be comprehensively detected.

Therefore, it becomes possible to control the engine mount so as to cancel the input from the road surface and the input from the power unit b with respect to the vehicle body a, and use the power unit b as a dynamic vibration absorber with respect to the road surface input.

Further, in claim 2, the first condition is set to X ₃ · ₁ <0.
And, the second condition | ₃ | <is A, and a third condition _{(X 3 / | X 3 |} ) · 1> With B, and reduction of the vehicle body a vibration performs precise control Can be improved.

Further, according to claim 3, the road surface input can be accurately detected by the unsprung mass detection means k, and a predetermined value used when judging the second condition and the third condition based on the detected value. By making A and B variable, more accurate control becomes possible.

Furthermore, according to claim 4, in the above claim 3, by setting A = K ₁ (| ₀ |) max and B = K ₂ (| ₀ |) max, more precise control is performed. Therefore, the vibration of the vehicle body can be remarkably reduced.

Example Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

That is, FIG. 2 shows a control type engine mount 10 showing an embodiment of the present invention, which is arranged between a vehicle body 12 and a power unit 14.
14 is supported on the vehicle body 12 with a cushioning action.

The control type engine mount 10 includes a first bracket 16 attached to the vehicle body 12 and a second bracket 18 attached to the power unit 14, and a support elastic body 20 is provided between the first and second brackets 16 and 18. It is attached by vulcanization adhesion or the like.

A main fluid chamber 24 defined by an orifice structure 23 in which an electrode orifice 22 is formed is formed inside the support elastic body 20 on the first bracket 16 side, and the main fluid chamber of the electrode orifice 22 is formed. The side opposite to 24 is covered with a diaphragm 26, and a sub fluid chamber 28 is formed between the electrode orifice 22 and the diaphragm 26.

The first bracket 16 is composed of a tapered cylindrical body 16a and a dish-shaped cover 16b which is caulked and fixed to the peripheral edge of the lower end of the tapered cylindrical body 16a in the drawing.
The peripheral edge portions of the orifice constituting body 23 and the diaphragm 26 are respectively caulked and fixed to the caulking portions of the 6a and the cover 16b.

The space defined by the diaphragm 26 and the cover 16b is an air chamber 30.

The electrode orifice 22 has a pair of electrode plates 22 on the upper and lower opposing walls of the orifice 22a that connects the main fluid chamber 24 and the sub fluid chamber 28.
It is configured by attaching b and 22c.

Then, the main fluid chamber 24, the sub-fluid chamber 28, and the electrode orifice 22 are filled with an electrorheological fluid as a variable viscosity fluid.

The electrorheological fluid has a property that its viscosity changes according to an applied voltage, and the viscosity increases when a strong electric field is applied by the applied voltage.

By the way, the vehicle body 12 is provided with a vertical acceleration sensor 32 as a vehicle body movement detecting means, and the vertical acceleration sensor 32 detects a vertical displacement acceleration of the vehicle body 12.

Further, in the sub-fluid chamber 28, a pressure sensor 34 as an in-orifice fluid motion detecting means attached to the lower end of the orifice structure 23 is provided, and the pressure in the sub-fluid chamber 28 is changed by the pressure sensor 34 one by one. Is detected.

That is, since the pressure in the sub-fluid chamber 28 is changed by the liquid (electrorheological fluid) flowing in and out through the orifice 22a, the pressure sensor 34 detects the pressure in the sub-fluid chamber 28. The movement state of the liquid in the orifice 22a will be detected.

The state of movement of the liquid in the orifice 22a depends on the air chamber 3
It can also be obtained by detecting the pressure within zero.

Then, the vertical acceleration sensor 32 and the pressure sensor
The acceleration signal and the pressure signal detected by 34 are output to the controller 36 as the control means for calculating the control voltage, and the controller 36 outputs the control to the electrode orifices 22b and 22c based on these signals. Calculate the voltage.

Then, the result calculated by the controller 36 is output to the voltage output unit 38, and the voltage output unit 38 outputs the result to the electrode plate 22.
A control voltage according to the calculation result of the controller 36 is applied to b and 22c.

In the controller 36, a first condition for judging the moving direction of the fluid in the vehicle body 12 and the orifice 22a based on the detection values of the vertical acceleration sensor 32 and the pressure sensor 34,
A second condition for determining the magnitude of the velocity of the fluid in the orifice 22a based on the predetermined value A and a third condition for determining the magnitude of the velocity of the vehicle body 12 based on the predetermined value B are obtained. The voltage output unit based on the judgment results of the second and third conditions
The control signal output to 38 is determined.

As the first condition and X ₃ · _{1 <0,} the second condition | ₃ | <is A, and, as the third condition (X ₃ / | X ₃
|) ・₁ > B is desirable.

Note that X ₁ and X ₃ are the displacement amount of the vehicle body 12 and the displacement amount of the fluid in the orifice 22a as shown in the model diagram of FIG. 3, and X ₀ shown in FIG. The amount X ₂ is the amount of displacement of the power unit 14.

By the way, the model diagram shown in FIG. 3 shows a vibration system of the entire vehicle including the control type engine mount 10, the vehicle body 12, the power unit 14 and the unsprung portion 40, and the vehicle body mass MS as a mass body is a suspension spring. Unsprung through KS 40
Supported by the vehicle body mass MS and the power unit mass
Controlled engine mount 10 is arranged between MP and.

At this time, the control-type engine mount 10 includes the liquid mass MO in the orifice 22a, the expansion spring KO of the main fluid chamber 24,
The orifice 22a is designed so that the fluid resonance in the orifice 22a due to the cross-sectional area ratio R of the orifice 22a acts as a dynamic vibration absorber against the resonance due to the upper and lower springs of the power unit mass MP and the support elastic body 20 itself and the expansion spring KP + KO. The liquid resonance frequency f ₀ inside is set.

With the above configuration, the control type engine mount 10 of the present embodiment
In this case, when the vibration is input from the vehicle body 12, the supporting elastic body 20
Is deformed to change the volume in the main fluid chamber 24, and the pressure-changing fluid in the main fluid chamber 24 changes the pressure in accordance with the expansion spring of the supporting elastic body 20 forming the side wall of the main fluid chamber 24. The orifice 22 is moved to and from the auxiliary fluid chamber 28 via the orifice 22a.

At this time, fluid vibration occurs in the electrode orifice 22, and at a specific frequency of the input vibration, the movable fluid in the orifice 22a is a mass (liquid mass MO), and the expansion elasticity of the support elastic body 20 is a spring (expansion spring KO). The resonance phenomenon occurs.

At this time, by applying a high voltage to the electrode plates 22b and 22c of the electrode orifice 22, the viscosity of the electrorheological fluid in the orifice 22a increases, and the viscosity of the liquid (electrorheological fluid) passing through the orifice 22a increases. The increased resistance allows the damping coefficient of the control engine mount 10 to be controlled.

FIG. 4 shows the displacement transmissibility (| X ₁ | / | X ₀ of the vehicle body 12 when the unsprung part 40 is excited in the model of the vibration system shown in FIG.
|) Characteristics, and the damping coefficient C of the liquid mass MO above
It is known that the displacement transmissibility varies depending on the size of O.

In the figure, the characteristic a is the resonance characteristic when the voltage applied to the electrode orifice 22 is stopped in the control type engine mount 10 (when the control is not performed), and the characteristic c is the resonance of the liquid filled engine mount in which a liquid of constant viscosity is filled. A curve and a characteristic b are resonance characteristics when a voltage is applied to the electrode orifice 22 in the control type engine mount 10, and a characteristic d is a resonance characteristic when the control type engine mount 10 is operated under the control to be performed in this embodiment. It is a resonance characteristic.

By the way, in the control-type engine mount 10, when a relatively low-frequency vibration (engine shake, etc.) is input from the power unit 14 or the vehicle body 12 side, the supporting elastic body 20 is deformed by the exciting force at this time, and the mainstream flow occurs. The pressure in the body chamber 24 is changed.

At this time, due to the phase delay characteristic of vibration, the liquid mass MO is substantially in phase with the relative displacement (X ₂ −X ₁ ) of the power unit 14 when vibrating on the lower frequency side than the resonance frequency f ₀ shown in FIG. When moving at resonance, it moves with a phase difference of 90 ° with the relative displacement, and when vibrating at a frequency exceeding the resonance frequency f ₀ , it moves in a phase (180 ° delay) approximately opposite to the relative displacement. .

On the other hand, in each of these states, the controller 36 detects the vertical acceleration on the vehicle body side by the detection value from the vertical acceleration sensor 32, and the orifice 22 by the pressure sensor 34.
The pressure in the sub-fluid chamber 28, which is proportional to the liquid displacement X ₃ in a, is detected, each state change and phase information of the vibration system is grasped based on each of these detection information, and it is output to the voltage output unit 38. The control signal is determined.

FIG. 5 is an algorithm used when the control signal is determined by the controller 36, and the algorithm is calculated every predetermined short time to determine the ON / OFF switching timing of the applied voltage.

That is, in the above algorithm, first, the pressure Pb in the sub-fluid chamber 28 detected by the pressure sensor 34 is input as the liquid displacement X ₃ in the orifice 22a, and the vertical acceleration on the vehicle body 12 side detected by the vertical acceleration sensor 32. ₁ is input.

Then, the liquid displacement X ₃ is further obtained through a differentiator I to obtain a time derivative value ₃ , and the vertical acceleration ₁ is further obtained through an integrator II to obtain a time integral value ₁ .

The four values X ₃ , ₃ , ₁ , ₁ together with the predetermined values A and B set in advance are the _first , _second and _third values for determining the control signal to be output to the voltage output section 38 by the determination circuit III. The third condition is determined.

That is, the first condition as described above and X ₃ · _{1 <0,}
The second condition is (X ₃ / | X ₃ |)> B, and the third condition is |
₃ | <A, the determination circuit III determines whether or not all of these three conditions are satisfied, and outputs an ON signal to the voltage output unit 38 if the three conditions are satisfied. When at least one of the three conditions is not satisfied, an OFF signal is output to the voltage output unit 38.

In this way, by outputting an ON signal from the controller 36 to the voltage output section 38, a voltage is applied from the voltage output section 38 to the electrode plates 22b and 22c of the electrode orifice 22, and the electrorheological fluid in the orifice 22a is discharged. While the viscosity is increased, an OFF signal is output to the voltage output unit 38, so that the voltage application from the voltage output unit 38 to the electrode plates 22b and 22c is stopped.

Then, by controlling the applied voltage using the first, second, and third conditions, vibrations in a frequency region smaller than the resonance frequency (f _{0 in} FIG. 4) of the liquid in the orifice 22a are suppressed. For example, the applied voltage is almost ON.

At this time, due to the increase of the viscous resistance in the orifice 22a,
The movement of the liquid mass MO becomes slow, the liquid mass MO cannot function as a dynamic vibration absorber, and the resonance phenomenon of the power unit 14 viewed from the vehicle body 12 side becomes remarkable.

However, since the phase difference between the vehicle body displacement X ₁ and the power unit displacement X ₂ does not exceed 90 ° in the frequency region smaller than the resonance frequency f ₀ , the resonance phenomenon of the power unit 14 causes the dynamic vibration absorber with respect to the vehicle body 12. Began to work as an unsprung 40
The vibration on the vehicle body 12 side excited by is significantly reduced (for example, the resonance curve at this time has a characteristic b in FIG. 4).

On the other hand, with respect to the vibration in the frequency region higher than the resonance frequency f ₀ , the applied voltage becomes substantially OFF, the viscous resistance of the liquid in the orifice 22a decreases, and the liquid mass MO acts as a dynamic vibration absorber. As a result, the resonance phenomenon of the power unit 14 is suppressed and the vibration of the vehicle body 12 is reduced (for example, the resonance curve at this time has the characteristic c in FIG. 4).

Further, the control for the vibration in the frequency region near the resonance frequency f ₀ is performed by ON / OFF controlling the applied voltage, and FIG. 6 shows the temporal switching state at this time.

That is, the characteristic of the vibration displacement from the unsprung portion 40 is shown in the figure (a), and the respective displacement characteristics of the vehicle body 12, the power unit 14, and the liquid in the orifice 22a with respect to the control voltage are shown in the figure (b). Inputs FO, FE, FS shown and shown in (c) are transmitted to the vehicle body through the unsprung part 40, the support elastic body 20 of the control type engine mount 10 and the enclosed liquid, respectively.
The change characteristics of are shown.

By the way, in the control type engine mount 10 of the present embodiment, the time interval between the ON state and the OFF state of the applied voltage changes in the vicinity of the resonance frequency f ₀ as shown in FIG. In comparison with the case of non-control shown in FIG. 7 by performing such control, when the orifice damping is changed by this control law shown in the algorithm of FIG. 5, the displacement X of the power unit 14 is changed. It is understood that the phase of ₂ is advanced.

That is, this means that the phases of the forces FE and FO input to the vehicle body 12 via the control engine mount 10 and the force FS input to the vehicle body 12 from the unsprung portion 40 are changed to substantially opposite phases. Means that FE and FO and FS cancel each other out,
As a result, the total input transmitted to the vehicle body 12 is reduced.

In this way, by changing the attenuation value of the electrode orifice 22 at the control timing according to the present control law, the power unit mass MP and the liquid mass MO can be effectively used for the displacement input from the unsprung part 40. As shown in the d characteristic of the figure, the vehicle body vibration can be remarkably reduced over the entire frequency range.

When the control is performed according to this control law, the vibration can be reduced by 7 to 10 dB as compared with the non-controlled case.

FIG. 8 shows an algorithm used in another embodiment of the present invention, in which the comparison parameters A and B used in the algorithm shown in FIG. 5 are proportionally changed by the vibration displacement from the unsprung part 40. Is.

That is, in this embodiment, an unsprung member such as a suspension link, which is the unsprung member 40, is provided with an unillustrated acceleration sensor as unsprung motion detecting means, and the unsprung acceleration ₀ obtained from the acceleration sensor is input to the controller 36. As shown in FIG. 9, the unsprung mass acceleration ₀ is input to the maximum value (| _{0 at} every predetermined sampling period (for example, 100 mSec)).
|) Max is required.

Then, comparison parameter A shown in FIG. 5, B is the gain K _1, K _2, which is set in advance, respectively, A = K ₁ (|
₀ |) max, B = K ₂ (| ₀ |) max, and the decision circuit III determines the third condition and the second condition based on these A and B.

The gains K ₁ and K ₂ are values determined by the characteristics of the vehicle using the control type engine mount 10 and are obtained by experiments.

Therefore, when the control type engine mount 10 is controlled according to the control law of this embodiment, the control voltage can be controlled more precisely according to the magnitude of the input from the unsprung portion 40, and particularly, the extremely large road surface. There is a control effect when it is excited by the displacement from.

As described above, according to the control type engine mount of the present invention, in the first aspect, the voltage applied to the electrode orifice is
A first condition determined by the movement direction of the vehicle body and the fluid in the orifice, a second condition determined by the magnitude of the velocity of the fluid in the orifice based on a predetermined value A, and a magnitude of the vehicle body velocity set by a predetermined value B. Since it is controlled by the third condition determined based on the above, it is possible to comprehensively detect the state of the engine mount and the vibration state of the vehicle body.

Therefore, the engine mount is controlled so as to cancel the input from the road surface and the input from the power unit to the vehicle body, and the liquid mass in the orifice is used as a dynamic vibration absorber. It becomes possible to use it as a dynamic vibration absorber, and the control effect can be remarkably improved.

Further, in claim 2, the first condition is set to X ₃ · ₁ <0.
And, the second condition | ₃ | <is A, and a third condition _{(X 3 / | X 3 |} ) · 1> By is B, further reducing the effect of vehicle body vibrations by performing a dense control Can be improved.

Further, according to claim 3, the road surface input can be accurately detected by the unsprung motion detecting means, and the predetermined value A used when judging the second condition and the third condition based on the detected value. By making B and B variable, more accurate control can be performed.

Further, according to claim 4, in the above-mentioned claim 3, further precise control is performed by setting A = K ₁ (| ₀ |) max and B = K ₂ (| ₀ |) max. Therefore, even when a large amount of displacement vibration is applied from the unsprung part, it is possible to significantly reduce the vibration of the vehicle body.

[Brief description of drawings]

1 is a sectional view showing a concept of the present invention, FIG. 2 is a sectional view showing an embodiment of the present invention, FIG. 3 is a shape model diagram showing a vibration system of an entire vehicle to which the present invention is applied, FIG. 4 is a characteristic diagram of the vibration transmissibility which is changed according to the control mode, FIG. 5 is an explanatory diagram of a control algorithm used in one embodiment of the present invention, and FIG. 6 is a diagram of the control algorithm of the present invention. FIG. 7 is a characteristic diagram showing state changes in time series, FIG. 7 is a characteristic diagram showing state changes in non-control state of the present invention in time series, and FIG. 8 is an explanatory diagram of a control algorithm used in another embodiment of the present invention. , FIG. 9 is an explanatory diagram showing an example of sampling of unsprung acceleration used in the algorithm of FIG. 10 …… Control type engine mount, 12 …… Car body, 14 …… Power unit, 20 …… Support elastic body, 22 …… Electrode orifice, 22a …… Orifice, 22b, 22c …… Electrode plate, 24 …… Main fluid chamber , 28 ... Sub-fluid chamber, 32 ... Vertical acceleration sensor (vehicle body movement detection means), 34 ... Pressure sensor (orifice fluid movement detection sensor), 36 ... Controller (control means), 38
...... Voltage output section.

Claims (4)

[Claims] 1. An elastic body arranged between a vehicle body and a power unit, a main fluid chamber arranged in parallel with the elastic body and having a volume changed by input vibration, and communicated with the main fluid chamber via an electrode orifice. A sub-fluid chamber having a variable volume is provided, and an electrorheological fluid whose viscosity is changed according to an applied voltage is enclosed in the main and sub-fluid chambers and the electrode orifice to change the attenuation rate in the electrode orifice. In a control-type engine mount, a vehicle body movement detecting means for detecting a vertical movement of a vehicle body, an in-orifice fluid movement detecting means for detecting a fluid movement in an electrode orifice, and a vehicle body movement detecting means and an in-orifice fluid movement detecting means. A first condition for judging the moving directions of the fluid in the vehicle body and the orifice based on the detected value of the means, and the magnitude of the velocity of the fluid in the orifice is judged based on the predetermined value A. A control for determining a second condition and a third condition for judging the magnitude of the speed of the vehicle body based on a predetermined value B, and controlling the voltage applied to the electrode orifice based on these first, second and third conditions. A control type engine mount, characterized in that it is provided with means. 2. A displacement amount X ₁ of the vehicle body, if the displacement of the fluid within the orifice was X _3, the first condition is given by X ₃ · _{1 <0,} the second condition is | ₃ | In <A The controlled engine mount according to claim 1, wherein the third condition is given by (X ₃ / | X ₃ |) · ₁ > B. 3. An unsprung movement detecting means for detecting the unsprung movement of the suspension is provided, and the predetermined values A and B are variable according to the detection value of the unsprung movement detecting means. The control type engine mount according to 1 or 2. 4. When the unsprung displacement amount is X ₀ and the preset gains according to the vehicle are K ₁ and K ₂ , the maximum unsprung acceleration (| ₀ |) max within a fixed time , A = K ₁ (|
4. The control type engine mount according to claim 3, wherein ₀ |) max and B = K ₂ (| ₀ |) max.