JPH0366945A - Control type engine mount - Google Patents

Abstract

PURPOSE:To greatly simplify the constitution by way of making a detection means as a car body movement detection means by constituting a voltage to apply to an electrode orifice by a control means on the basis of the displacement detected by the car body movement detection means and the displacement of fluid assumed by an assumption means or a power unit displacement. CONSTITUTION:The movement of a car body in the vertical direction is detected by a car body movement detection means (g). On the basis of this detected value, the displacement of fluid inside an electrode orifice (e) or the displacement of a power unit (b) is assumed by an assumption means (h). On the basis of the displacement detected by the car body movement detection means (g) and the fluid displacement assumed by the assumption means (h) or the power unit displacement, it is controlled by a voltage control means 1 to apply to the electrode orifice (e).

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is directed to an electrorheological fluid whose viscosity changes depending on an applied voltage, and which changes the fluid viscosity within an orifice provided between a main fluid chamber and a sub-fluid chamber. This invention relates to a controlled engine mount that allows variable

BACKGROUND ART As this type of controlled engine mount, for example, there is a control type engine mount disclosed in Japanese Patent Application Laid-open No. 104828/1983. ) Main fluid chamber (upper chamber) formed within
and an auxiliary fluid chamber (lower chamber) defined by an elastic wall through an electrode orifice, that is, an orifice provided with an electrode plate. Filled with rheological fluid,
By changing the voltage applied to the electrode plate in response to the input vibration, the flow state of the fluid in the orifice is changed, thereby making it possible to adjust the vibration transmission state as appropriate.

Problems to be Solved by the Invention However, in such conventional controlled engine mounts, vibrations transmitted between the vehicle body and the power unit via the engine mount are input via the supporting elastic body itself; When the fluid is moved between the main and auxiliary fluid chambers through the orifice, the phase with the input via the expansion elasticity is 00 to 18 due to the dynamic vibration absorber action with the mass of the fluid in the orifice.
It can be changed up to 0°.

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

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

In other words, in conventional solid type (solid rubber body) engine mounts, the power unit resonates near 1002 and engine shake occurs, but in an area where the frequency is slightly lower than this resonance point. A region in which the vibration transmissibility is significantly reduced appears in a region where the frequency is slightly higher than the resonance point, and the vibration transmission to the vehicle body side becomes significantly large.

Therefore, in order to reduce the area where the vibration transmissibility deteriorates,
If the engine mount is a liquid-filled type and the phenomenon in which a liquid with a constant viscosity resonates within the orifice is used to improve the area where the transmission rate deteriorates, the area where the frequency is slightly lower than the resonance point will be affected by resonance. A region where the transmissibility deteriorates due to an increase in the loss factor appears.

Therefore, in the above-mentioned controlled engine mount, by changing the fluid viscosity in the orifice, it is possible to improve the region where the transmission rate deteriorates due to the increase in the loss factor. Conventional control of type engine mounts focuses on suppressing the displacement of the power unit, so the transmission rate at that time is different between the solid type engine mount and the liquid filled type engine before and after the resonance point. The characteristics are a compromise between the two engine mounts, and while they are superior to both engine mounts in some respects, they are inferior to both engine mounts in other respects.

Therefore, the present invention considers the point of input to the vehicle body as a reference, sets the power unit to a state where it can vibrate in a certain frequency range, and uses the power unit as the mass of a dynamic vibration absorber, thereby combining input vibration from the road surface. An object of the present invention is to provide a controlled engine mount that can significantly reduce input vibration to a vehicle body in a vibration system of the entire vehicle.

Means for Solving the Problems In order to achieve this object, the invention of claim 1, as shown in FIG. A main fluid chamber d is arranged in parallel with C and whose volume can be changed by human vibration, and a sub fluid chamber f whose volume is variable and which is communicated with the main fluid chamber d via an electrode orifice e, and these main and sub fluid chambers d , f and an electrode orifice e, in which an electrorheological fluid whose viscosity changes depending on the applied voltage is sealed, and the damping rate in the electrode orifice e is changed. a vehicle motion detection means g for detecting the vehicle motion detection means g; and an estimation means for estimating the displacement of the fluid in the electrode orifice e or the displacement of the power unit b based on the detection value detected by the vehicle motion detection means g; It is constructed by providing a control means i for controlling the voltage applied to the electrode orifice e based on the displacement detected by the vehicle body motion detection means g and the fluid displacement or power unit displacement estimated by the estimation means.

Further, the invention of claim 2 is the invention of claim 1, which includes:
The vehicle body acceleration (■1) is determined by the vehicle body motion detecting means g, and the acceleration time integral value (statement 1) and the acceleration time integral value (■1) are determined from the vehicle body acceleration (■1), and these , and from Xl by the above estimation means, the fluid displacement X
At the same time as estimating l, the control means i calculates the fluid velocity large from Xl, and the first condition is given by , and (father, /1■1)・×1> Find the third condition given by B (B is a parameter), and set these first conditions.
．． Second. The configuration is such that the voltage output to the electrode orifice is turned ON when all the third conditions are satisfied, and the voltage is turned OFF otherwise.

Furthermore, the invention of claim 3 is based on the invention of claim 1 or 2, in which the vehicle body displacement (■1) and the vehicle body speed (statement 1) obtained by the vehicle body motion detection means g, and the equivalent power unit mass (1) obtained as the setting parameter. MO), electrode orifice e
fluid mass (MO) within.

The support rigidity (Kll) of the support elastic body C, the expansion rigidity (KO) of the support elastic body C, and the main body damping (Cg) of the support elastic body C.

From the fluid attenuation (CO) in the electrode orifice e, the ratio of the cross-sectional area of the orifice e to the cross-sectional area of the main fluid chamber d (R), and the sampling time (at), the displacement of the power unit b (■1) and the Fluid displacement (■1)
(nl, e, represent estimated values before sampling once and twice).

With the above structure, the controlled engine mount of the invention according to claim 1 detects the movement of the vehicle body in the vertical direction by the vehicle body motion detecting means g, and based on the detected value detected by the vehicle body motion detecting means g, The estimating means estimates the displacement of the fluid in the electrode orifice e or the displacement of the power unit b, and calculates the displacement detected by the vehicle body movement detecting means g and the fluid displacement or the power unit displacement estimated by the estimating means. Based on this, since the voltage applied to the electrode oriice e is controlled by the control means i, it is only necessary to provide one vehicle body motion detection means g as a detection means when determining each state quantity for determining the control voltage. good.

Further, the invention of claim 2 is the invention of claim 1, which includes:
The vehicle body acceleration (■1) is determined by the vehicle body motion detection means g, and the acceleration time integral value (statement 1) and the acceleration time integral value (■1) are determined from the vehicle body acceleration (■1), and these 5 <1 and
Calculate the fluid velocity 5C3 from, the first condition given by I3・father+<0, the second condition given by I*, I<A (A is a parameter), and (■1/|■1|) ·Big.

> Find the third condition given by B (B is a parameter),
These first. Second. If all the third conditions are met, the voltage output to the electrode orifice is turned ON, otherwise the voltage is turned OFF, so the condition of the engine mount and the vibration condition of the vehicle body can be comprehensively detected and accurate detection can be performed. Voltage control can be performed.

Furthermore, the invention of claim 3 is based on the invention of claim I or 2, in which the vehicle body displacement (■1) and vehicle body speed (statement 1) obtained by the vehicle body motion detection means g, and the equivalent power unit mass (1) obtained as a setting parameter. M1).

Fluid mass (MO) in electrode orifice e, supporting elastic body C
Support stiffness (KE) of supporting elastic body C, expansion stiffness (KE) of supporting elastic body C
, the body damping (CI) of the support elastic body C, the fluid damping in the electrode orifice (CO), the ratio of the cross-sectional area of the orifice e to the cross-sectional area of the main fluid chamber d (R), and the sampling time (Δ
t), the power unit displacement (Xo) and the fluid displacement in the electrode orifice e (I3) RKoX s--+
+fwinter',':,,ノX 16-1+fKa+ (1+
R)Ko)X ++ CKX ++ R(1,000R)l
[OX, + Co large, J (1%-It R-1 is
Represents the estimated value before sampling once and twice. ), the power unit displacement (■1
) and the fluid displacement (XS) in the electrode orifice e are closer to the actual measured values, and the estimation variable can be composed only of the displacement for the second-order differential equation unique to the vibration system, so signal processing is easier. can be carried out quickly, and even if noise is present in the signal detected by the vehicle body motion detection means g, it can be detected with high accuracy.

Example Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

That is, FIG. 2 shows a controlled engine mount 10 showing an embodiment of the present invention. Support with action.

The controlled 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. Support elastic body 2 between second bracket 16 and 18
0 is attached by vulcanization adhesive or the like.

Inside the supporting elastic body 20 on the first bracket 16 side,
Orifice structure 23 in which electrode orifice 22 is formed
A main fluid chamber 24 defined by
A side of the electrode orifice 22 opposite to the main fluid chamber 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 lower end peripheral edge of the tapered cylindrical body 16a in the figure. The peripheral edges of the oriice structure 23 and the diaphragm 26 are each caulked and fixed to the caulked portions of the cover 16b.

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

The electrode orifice 22 has a main fluid chamber 24 and a sub fluid chamber 2.
It is constructed by attaching one pair of electrode plates 22b and 22C to the upper and lower opposing walls of the orifice 22a communicating with the orifice 8.

Further, the main fluid chamber 24. An electrorheological fluid as a variable viscosity fluid is sealed within the sub-fluid chamber 28 and the electrode orifice 22 .

The electrorheological fluid has a property that the viscosity changes depending on the applied voltage, and the viscosity increases when a strong electric field is applied by the applied voltage.

Incidentally, the vehicle body 12 is provided with a vertical acceleration sensor 32 as a vehicle body motion detecting means.
2, the vertical displacement acceleration of the vehicle body 12 is detected.

The acceleration signal detected by the vertical acceleration sensor 32 is output to the controller 36, and the controller 36 controls the electrode orifice 2 based on the acceleration signal.
The control voltage to be output to 2b and 22C is determined.

That is, the controller 36 is provided with an estimation means 38 for estimating the displacement of the fluid in the electrode orifice 22 and the displacement of the power unit 14 based on the acceleration signal detected by the vertical acceleration sensor 32, and The acceleration signal detected by the vertical acceleration sensor 32 and the fluid displacement or power estimated by the estimation means 38
Based on the displacement of the unit 14, the electrode orifice 22
A control means 40 is provided for calculating the voltage applied to.

The result calculated by the control means 40 is output to the voltage output section 42, and the voltage output section 42 outputs the result to the electrode plate 2.
A control voltage according to the calculation result of the control means 40 is applied to 2b and 22C.

The control means 40 sets a first condition for determining the movement direction of the vehicle body 12 and the fluid in the orifice 22a and the velocity of the fluid in the orifice 22a based on the detected value of the vertical acceleration sensor 32 and the estimated value of the estimation means 38. A second condition for determining the magnitude of the vehicle body 12 based on the predetermined value A, and a third condition for determining the magnitude of the speed of the vehicle body 12 based on the predetermined value B are determined. Second. The control signal to be output to the voltage output section 42 is determined based on the determination result of the third condition.

The first condition is X, ・×+<0, the second condition is l xsl <A, and the third condition is Te1
;! (X, / l X3+) - sentence, > B (!:
City is set.

Note that XI and X3 above 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. , is the displacement amount of the power unit 14.

By the way, the model diagram shown in FIG. 3 above shows the control type engine mount 10, the vehicle body 12. The vibration system of the entire vehicle including the Harry unit 14 and the unsprung section 40 is shown, and the vehicle body mass Ms as a mass body is supported by the unsprung section 40 via a suspension spring 8, and the vehicle body mass M
A controlled engine mount 10 is arranged between the power unit mass M8 and the power unit mass M8.

At this time, the controlled engine mount IO controls the liquid mass M in the orifice 22a. and an expansion spring K of the main fluid chamber 24. and the orifice 2 relative to the cross-sectional area of the main fluid chamber 24.
The liquid resonance in the orifice 22a due to the ratio R of the cross-sectional area of 2a causes the equivalent power unit mass M8 and the supporting elastic body 20
8 and expansion spring K on its own upper and lower springs. The liquid resonance frequency fo within the orifice 22a is set so as to act as a dynamic vibration absorber against resonance caused by the orifice 22a.

Although the power unit 14 is normally supported by three to four mounts, the above-mentioned equivalent power unit mass My< represents the equivalent mass supported by one mount in this embodiment.

By the way, the estimation means 38 calculates the vehicle body displacement (■1) and the vehicle body speed (×1) obtained by the vertical acceleration sensor 32.
), the equivalent power unit mass (ME) obtained as a setting parameter, and the fluid mass in the electrode orifice 22 (M
O), support rigidity (Kg) of support elastic body 20, expansion rigidity (KE) of support elastic body 20, main body damping of support elastic body 20 (
Ct), the fluid attenuation (CO) in the electrode orifice 22, the ratio (R) of the cross-sectional area of the orifice 22a to the cross-sectional area of the main fluid chamber 24, and the sampling time (Δt), and the power unit displacement (■1) and the inside of the electrode orifice. The fluid displacement (X3) is estimated using the following equations (1) and (2).

10R(1+R)KOX InCO sentence,]... ■In addition, EInn-* represents the estimated value before sampling once or twice.

With the above configuration, the controlled engine mount of this embodiment)1
0, when vibration is input from the vehicle body 12, the support elastic body 20 is deformed and the volume inside the main body chamber 24 is changed,
Due to the pressure change according to the expansion spring of the support elastic body 20 that constitutes the side wall of the main fluid chamber 24, the viscosity variable fluid in the main fluid chamber 24 flows between it and the sub fluid chamber 28 through the orifice 22a of the electrode orifice 22. be moved and be

At this time, fluid vibration occurs in the electrode orifice 22,
At a specific frequency of the input vibration, a resonance phenomenon occurs in which the movable fluid in the orifice 22a is a mass ff1 (liquid mass M) and the expansion elasticity of the supporting elastic body 20 is a spring (1 in the expansion spring).

At this time, the electrode plates 22b, 2 of the electrode orifice 22
By applying a high voltage to 2C, the orifice 22a
The viscosity of the electrorheological fluid in the orifice 22a increases, and the viscous resistance of the liquid (electrorheological fluid) passing through the orifice 22a increases, making it possible to control the damping coefficient of the controlled engine mount 10.

FIG. 4 shows the displacement transmission rate of the vehicle body 12 <IX
, I/lX, l), and it is known that the displacement transmissibility has different characteristics depending on the magnitude of the damping coefficient C8 of the liquid mass M0.

In the figure, characteristic a is when the voltage applied to the electrode orifice 22 is stopped in the controlled engine mount 10 (when not controlled)
The resonance characteristic, characteristic C, is the resonance curve of a liquid-filled engine mount filled with a liquid of constant viscosity, or the resonance characteristic when a voltage is applied to the electrode orifice 22 in the controlled engine mount 10, and the characteristic d is the resonance characteristic when the controlled engine mount 10 is operated with the control to be performed in this embodiment.

By the way, the above-mentioned control type engine mount 10 receives relatively low frequency vibrations (
When an engine shake (engine shake, etc.) is input, the supporting elastic body 20 is deformed by the excitation force at this time, and the pressure in the main fluid chamber 24 is changed.

At this time, due to the phase delay characteristic of vibration, the liquid mass Mo is
When the power unit 14 is vibrating at a frequency lower than the resonance frequency fo shown in FIG.
- 180° delay).

On the other hand, in each of these states, the controller 36 detects the vertical acceleration of the vehicle body based on the detected value from the vertical acceleration sensor 32, estimates the liquid displacement X3 in the oriice 22a using the estimating means 38, and uses these detected information. Based on this, each state change and phase information of the vibration system are grasped, and a control signal to be output to the voltage output section 42 is determined.

FIG. 5 shows the controller 36. This is an algorithm used when determining a control signal in , and is calculated at predetermined short time intervals to determine the ON/OFF switching timing of the applied voltage.

That is, in the above algorithm, first, the liquid displacement X3 in the orifice 22a estimated by the estimation means 38 is input, and the vertical acceleration of the 12 vehicle bodies detected by the vertical acceleration sensor 32 is input.

Then, the liquid displacement Xs is further passed through a differentiator (2) to obtain a large time differential value, and the vertical acceleration X is further passed through an integrator (2) to obtain a large time integral value.

is required.

The above four values X3. Large 5. , ×1 is the first value for determining the control signal to be outputted to the voltage output section 42 by the judgment circuit (3) together with preset predetermined values A and B.
．． Second. A third condition is determined.

In other words, as mentioned above, the first condition is X1 father, <0,
The second condition is (XI/lX11)>B, and the third condition is l Ll <A, and the above judgment circuit
It is determined whether all three conditions are satisfied, and
If two conditions are met, an ON signal is sent to the voltage output section 42.
On the other hand, if at least one of the three conditions is not satisfied, an OFF signal is output to the voltage output section 42.
Output to.

In this way, from the controller 36 to the voltage output section 42,
By outputting the N signal, a voltage is applied from the voltage output section 38 to the electrode plates 22b and 22c of the electrode orifice 22, and the viscosity of the electrorheological fluid in the orifice 22a is increased. By outputting the OFF signal, the electrode plate 2 is output from the voltage output section 42.
The voltage application to 2b and 22C is stopped.

And the above 1. Second. By controlling the applied voltage using the third condition, the applied voltage is approximately ON for vibrations in a frequency range smaller than the resonance frequency (fo in FIG. 4) of the liquid in the orifice 22a. occupied by

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

However, in a frequency range smaller than the resonance frequency fo, the phase difference between the vehicle body displacement As a result, the vibrations on the vehicle body 12 side that are excited from the unsprung portion 40 are significantly reduced (for example, the resonance curve at this time has the characteristic shown in FIG. 4).

On the other hand, for vibrations in a frequency range larger than the resonance frequency fo, the applied voltage is approximately OFF, the viscous resistance of the liquid in the orifice 22a decreases, and the liquid mass M
O now works as a dynamic vibration absorber, and power unit 1
4 is suppressed, and the vibration of the vehicle body 12 is also reduced (for example, the resonance curve at this time is characteristic a in FIG. 4).

Further, control of vibration in the frequency range near the resonance frequency f0 is performed by controlling the applied voltage on and off, and the temporal switching state at this time is shown in FIG.

That is, in the same figure, (a) shows the characteristics of excitation displacement from the unsprung portion of the suspension, and (b) shows the characteristics of the vehicle body 12, power unit I4, and orifice 2 with respect to the control voltage.
The displacement characteristics of each of the liquids in 2a are shown, and (C
) The figure shows the change characteristics of inputs FO, FB, and Fs that are transmitted to the vehicle body via the unsprung mass 40, the supporting elastic body 20 of the controlled engine mount 10, and the enclosed liquid, respectively.

By the way, in the controlled engine mount 10 of this embodiment, as shown in the above figure (b), the time interval between the ON state and the OFF state of the applied voltage does not change appreciably in the vicinity of the resonance frequency fo. By performing such control, compared to the non-control case shown in FIG. 7, when the orifice damping is changed according to the control law shown in the algorithm shown in FIG. 5, the displacement X of the power unit 14, It is understood that the phase is ahead.

That is, this means that the phases of the forces Fg and Fo input to the vehicle body 12 via the controlled engine mount 10 and the force Fs input to the vehicle body 12 from under the springs are changed to substantially opposite phases. However, these F8 and F. and F8 cancel each other out, and 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 Mt and the liquid mass M are adjusted in response to the displacement input from the unsprung area. can be effectively utilized, and as shown in the d characteristic in FIG. 4, vehicle body vibration can be significantly reduced over the entire frequency range.

In addition, when control is performed according to this control law, it is possible to reduce vibration by 7 to 104 B compared to the case without control.

By the way, in this embodiment, when determining the fluid displacement (X3) of the electrode orifice 22, each parameter of the calculation model shown in FIG. Since the estimation is carried out using the equations, the equations (1) and (4) require relatively little signal processing (number of calculations), and stable estimated values can be obtained with a rough sampling time.

In addition, this direction is unique in that the estimation variable can be composed only of the displacement (of the mass point) (the velocity ring is not used as a variable) for the second-order differential equation peculiar to the vibration system. In this way, when the fluid displacement is estimated using the above formulas (1) and (2), even if the initial value is undetermined, the estimation error becomes a small value over time, and there is no problem in actual control.

Therefore, in the estimation direction of this embodiment, quick processing can be achieved due to less signal processing, and the burden on the controller 36 can be reduced.
It is strong against the detection signal of , and each state quantity can be determined by one sensor.

As described in detail, the controlled engine mount of the present invention comprises:
In claim 1, the vertical movement of the vehicle body is detected by the vehicle body motion detection means, and the estimating means is configured to detect the displacement of the fluid in the electrode orifice or the displacement of the power unit based on the detected value detected by the vehicle body motion detection means. The displacement is estimated, and the voltage applied to the electrode orifice is controlled by the control means based on the displacement detected by the vehicle body motion detection means and the fluid displacement or power unit displacement estimated by the estimation means. In determining each state quantity for determining the control voltage, only one vehicle body motion detection means is required as a detection means, and the configuration can be greatly simplified.

Further, the invention of claim 2 is the invention of claim 1, which includes:
The vehicle body acceleration (■1) is determined by the vehicle body motion detection means, and the acceleration time integral value (statement 1) and the acceleration time integral value (■1) are determined from the vehicle body acceleration (■1), and these statements, From the above estimation means, the fluid displacement X3
At the same time, the control means i calculates the fluid velocity large from the X3, and the first condition given by X5-5CI<0, the second condition given by *31<A (A is a parameter), and , (■1/|■1|)・sentence, find the third condition given by >B (B is a parameter), and
．． Second. If all the third conditions are met, the voltage output to the electrode orifice is turned ON, otherwise the voltage is turned OFF, so the condition of the engine mount and the vibration condition of the vehicle body can be comprehensively detected, and the actual Therefore, accurate voltage control can be performed.

Furthermore, the invention of claim 3 is the invention of claim 1 or 2, in which the vehicle body displacement (■1) and vehicle body speed (large 1) obtained by the vehicle body motion detection means and the equivalent power unit mass (ME ).

fluid mass in the electrode orifice (MO), support stiffness of the support elastic (Kl), expansion stiffness of the support elastic (KO).

The power unit displacement (■1 ) and the fluid displacement (X3) in the electrode orifice as 0R(1+R)l[oX I0Co large,] (o1.E represents the estimated value before sampling once and -2 times.) By estimating, the estimation variable can be composed only of displacement, so signal processing can be performed quickly. Moreover, even if there is noise in the signal detected by the vehicle motion detection means, the It achieves various excellent effects such as being able to accurately detect and control the engine mount with little influence from noise.

[Brief explanation of drawings]

FIG. 1 is a claim correspondence diagram showing the concept of the present invention, FIG. 2 is a sectional view showing an embodiment of the present invention, and FIG. 3 is a shape model diagram showing the vibration system of the entire vehicle to which the present invention is applied. Fig. 4 is a characteristic diagram of the vibration transmissibility that varies depending on the control mode, Fig. 5 is an explanatory diagram of the control algorithm used in one embodiment of the present invention, and Fig. 6 is a diagram showing the vibration transmissibility during control of the present invention. A characteristic diagram showing state changes in time series. FIG. 7 is a characteristic diagram showing state changes in time series during non-control of the present invention. 10... Control type engine mount, 12... Vehicle body,
14... Power unit, 20... Support elastic body, 2
2... Electrode orifice, 22a... Orifice, 2
2b, 22C... Electrode plate, 24... Main fluid chamber, 28
. . . Sub-fluid chamber, 32 . . . Vertical acceleration sensor (vehicle body motion detection means), 36 . . . Controller, 38 . Figure 1 Figure 3 Figure 4U extension Figure 4 MIEE (Mz> Figure 5 Figure 6 Figure 7

Claims (3)

[Claims] (1) A supporting elastic body disposed between the vehicle body and the power unit, a main fluid chamber disposed in parallel with the supporting elastic body whose volume changes due to input vibration, and a main fluid chamber communicating with the main fluid chamber via an electrode orifice. A sub-fluid chamber whose volume is variable, and an electrorheological fluid whose viscosity changes depending on the applied voltage is sealed in these main and sub-fluid chambers and the electrode orifice, so that the attenuation rate within the electrode orifice is changed. In the controlled engine mount, a vehicle body motion detection means detects vertical movement of the vehicle body, and a displacement of the fluid in the electrode orifice or a displacement of the power unit is determined based on a detected value detected by the vehicle body motion detection means. and a control means for controlling the voltage applied to the electrode orifice based on the displacement detected by the vehicle body motion detection means and the fluid displacement or power unit displacement estimated by the estimation means. Features a controlled engine mount. (2) The vehicle body acceleration (■_1) is determined by the vehicle body motion detection means, and the acceleration time integral value (■
_1) and acceleration twice time integral value (X_1),
The fluid displacement X_3 is estimated by the estimation means from these ■_1 and X_1, and the fluid velocity ■_3 is calculated from X_3 by the control means, and
The first condition given by _1<0, the second condition given by |■_3|<A (A is a parameter), and (■_1/
Find the third condition given by |■_1|)・■_1>B (B is a parameter), and if all of these first, second, and third conditions are satisfied, turn on the voltage output to the electrode orifice,
The controlled engine mount according to claim 1, wherein the voltage is turned off in other cases. (3) The vehicle body displacement (X_1) and vehicle body speed (■_1) obtained by the vehicle body motion detection means, the equivalent power unit mass (M_E) obtained as the setting parameters, the fluid mass in the electrode orifice (M_O), and the Support rigidity (K
_E), expansion stiffness of the supporting elastic (K_O), body damping of the supporting elastic (C_K), fluid damping in the electrode orifice (
C_O), the ratio of the orifice cross-sectional area to the cross-sectional area of the main fluid chamber (R), and the sampling time (Δt), the power unit displacement (X_2) and the fluid displacement in the electrode orifice (X_3) are calculated as follows: ▲Mathematical formula, chemical formula, table 3. The controlled engine mount according to claim 1, wherein the control type engine mount is estimated as follows.