JPH06328948A - Active engine mount device - Google Patents

Abstract

PURPOSE:To provide an active engine mount device capable of reducing amplitude by vibration of different frequency by constituting it of fixed and variable orifice parts, releasing the variable orifice part at the time of idling by a switching valve and making it suck and exhaust liquid by way of blocking it at other time. CONSTITUTION:A controller of an engine mount 3 constituted of an electromagnetic actuator A and a liquid working part B between an engine 1 and a car body 2 consists of an actuator drive circuit 41 to give a control signal to the electromagnetic actuator part A by receiving an engine speed synchronization pulse and an orifice control circuit 42 to give an opening and closing control signal of a switching valve 5 connected to an engine air suction negative pressure source of a manifold and others. At the time of idle rotation, the orifice control circuit 42 releases the switching valve 5 and carries out suction and exhaust of liquid at both of orifice parts b61, b62, and in other cases, by blocking it and carrying out suction and exhaust of liquid only at the fixed orifice part, it reduces the peak of vibration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an active engine
More particularly, the present invention relates to an active engine mount device that actively reduces engine noise of an automobile or the like.

[0002]

2. Description of the Related Art Recently, the demand for comfort of automobiles is high,
Engine vibration and noise reduction are progressing. Vibration that is a problem in the engine idle rotation region is engine roll resonance due to non-uniform combustion between cylinders or cycles.
So-called vibration (about 7 to 15 Hz) and explosion 1
It is a bumble vibration (about 20 to 35 Hz) that is mainly caused by the torque fluctuation due to the next component. Further, in the high rotation speed region, the exciting force due to the reciprocating inertial force of the engine motion system becomes a problem.

One of the elements that meets this demand is the improvement of the engine mount provided between the engine and the vehicle body side. In order to address the above problems, the engine mount is in the idle rotation range of the engine. It is necessary for the low-frequency vibration of the above to be largely attenuated and for the transmissibility to be small in the high rotation region.

FIG. 6 is a graph which is quoted when comparing the characteristics of anti-vibration rubbers. 100Hz on the vertical axis
The dynamic magnification Kd / Ks (the ratio of the dynamic spring and the static spring constant) is taken, and the horizontal axis shows the loss factor tan δ at 10 Hz. The vertical axis indicates the degree of vibration transmission, and the horizontal axis indicates the degree of vibration damping. The desired engine mount characteristic is in the lower right direction.

As described above, conventionally, a rubber material has been generally used for engine mounts, but it has not been possible to obtain rubber alone for the purpose of improving low-frequency vibrations such as shakes for the last 10 years. In order to generate a large damping force, an active engine mount device having a liquid working part (liquid filled mount) has been developed.

FIG. 7 shows an outline of a conventional active engine mounting apparatus, in which A is a coil a1.
And a vibration plate a2, an electromagnetic actuator section is shown, and B is a liquid operation section (liquid-filled mount). The electromagnetic actuator A and the liquid actuating unit B form an engine mount in the metal outer cylinder c1, and the engine mount is controlled by a controller (not shown).

The liquid operating section B includes liquid chambers b1 to b5 for filling oil, ethylene glycol, etc. between the liquid chambers b1 and b2 and between the liquid chambers b3 and b4.
Between the orifices b6 and b for sucking and discharging the liquid
7 respectively, and further supported by support rubbers b8 and b9. In addition, b10 is a metal part, and
3 and b11 are rubber parts.

In such an active engine mount device, the number of revolutions (frequency) of the engine is set as follows by using a controller (not shown) connected thereto.
Is controlled by.

When the input frequency is low (up to about 20H
z): The actuator A is not driven, and the vibration is damped in the liquid operation unit B. Between the liquid chamber b1 and the liquid chamber b2,
Also, the vibration energy of the engine is converted into heat energy and the vibration is attenuated by sucking and discharging the oil filled inside through the orifices b6 and b7 between the liquid chamber b3 and the liquid chamber b4, respectively. Further, the electromagnetic actuator A is partially driven to reduce the amplitude. The cross-sectional area of the liquid working chamber and the areas of the orifices b6 and b7 are determined so as to correspond to the shake near the idle.

When the input frequency is high (about 20 Hz
~): The inertia of the oil inside becomes large, and the suction and discharge between the liquid chambers are stopped (locked).
Cancel the input amplitude. In addition, the actuator unit A
The internal pressure is controlled by the amplitude of to prevent the dynamic spring from becoming high, preventing the transmission of high frequency vibrations.

Typical examples of such an active engine mount device are disclosed in Japanese Patent Application Laid-Open No. 4-362331 and Japanese Patent Application Laid-Open No. 3-24338. We aim to reduce the vibration of the.

[0012]

The active engine mount device as described above is higher in cost than the conventional engine mount, and its feasibility as a product is whether sufficient performance can be obtained near idle rotation. It depends.

However, in a four-cylinder large displacement diesel engine such as a light truck, as shown in FIG.
In order to obtain an effective reduction in the engine mount system, it is necessary to match the amplitude of the electromagnetic actuator with the vibration amplitude of the engine.

Although it is technically possible to increase the vibration amplitude of the actuator, as a result, the area of the actuator becomes large and the vibration amplifier also becomes large. This means that the feasibility of the layout becomes difficult. In particular, in narrow type small trucks, RVs, and the like having a narrow vehicle width, the space between the engine and the frame is small, and it is difficult to establish a layout. This is the "first problem".

The "second problem" is that the idle vibration that can be dealt with by controlling the actuator part is only the primary explosion component and cannot be dealt with by vibration such as shake. This shake is supported by the liquid hydraulic section, but if there are multiple engine roll resonances around 1000 rpm,
It is common to aim and tune at one frequency, and other effects cannot be obtained sufficiently.

That is, this is called an engine shake and has the characteristics observed on the floor of the passenger compartment as shown in FIG. In this case, the peak is around 500 rpm and 10
It occurs at two places around 00 rpm. Generally, the mount is tuned aiming at the shake during idle rotation, but in such a case, the peak frequency of the shake is different, so if you set it according to one of the frequencies, the other effect will not be obtained . Generally, it is known that the liquid operation part has a non-linear characteristic that structurally depends on the input amplitude. This is because the engine vibration amplitude near the idle of a large displacement 4-cylinder diesel vehicle is exponential with respect to the engine rotation. It is also supported by the decrease in.

The "third problem" is the liquid mount and
The effective spring coefficient of the support rubber in the liquid working part is shown by the following formula in order to effectively reduce the shake at idle when the electromagnetic actuator cannot cope, or bobble vibration.

[0018]

[Equation 1]

If the dynamic spring is set low with a focus on improving idle performance, engine displacement will increase, which will deteriorate steering stability, fear of interference between exhaust pipes, engine accessories and the like, or durability of the engine mount. There are problems such as deterioration of sex.

Therefore, the present invention provides an engine mount comprising an electromagnetic actuator portion provided between the engine and the vehicle body and a liquid operation portion having an orifice between the liquid chambers,
A controller that drives the electromagnetic actuator unit based on a rotation synchronization signal of the engine; and an active engine that damps engine vibrations in the liquid operation unit.
An object of the mount device is to reduce the engine vibration amplitude near the idle rotation of the engine without changing the layout of the engine peripheral part or the characteristics of the support rubber in the liquid operation part.

[0021]

In order to solve the above-mentioned problems, an active engine mount device according to the present invention comprises a fixed orifice portion having a specific cross-sectional area where the orifice gives a dynamic spring constant of the engine mount. It is composed of a variable orifice part, and when the controller detects the idle speed from the engine speed synchronizing signal, it turns ON / O by the switching valve without driving the electromagnetic actuator part.
By opening the FF valve and opening the variable orifice portion to suck and discharge the liquid together with the fixed orifice portion, the peak of engine shake during idle rotation is attenuated, and the idle rotation speed to the upper limit value of the idle rotation region is increased. When the engine speed is detected, the ON / OFF valve is closed by the switching valve to close the variable orifice part so that the liquid is sucked and discharged only by the fixed orifice part, so that the peak of the engine shake other than the idling speed is increased. Is characterized by attenuating.

[0022]

According to the present invention, when the controller detects the idle rotation region of the engine speed as shown by the slanted line in FIG. 8 from the engine rotation synchronizing signal, the electromagnetic actuator is not driven and the switching valve is controlled to control the liquid. The ON / OFF valve provided in the orifice of the operating section is opened to open the variable orifice section.

As a result, the liquid is sucked and discharged between the liquid chambers via the variable orifice and the fixed orifice.

In this case, if the variable orifice portion and the fixed orifice portion are allocated so as to have a sectional area at the dynamic spring constant of the engine mount corresponding to the peak P1 of the engine shake as shown in FIG. These engine amplitude peaks can be damped equivalently as the dynamic spring constant is reduced and the rubber is just softened, as shown by the dotted line in FIG.

When the controller detects the engine speed from the engine speed synchronizing signal to the upper limit of the idle speed, the switching valve is controlled to open the ON / OFF valve and close the variable orifice section.

As a result, the liquid is sucked and discharged between the liquid chambers only through the fixed orifice portion, and the dynamic spring constant (orifice cross-sectional area) of the engine mount by this fixed orifice portion is assigned to the peak P2 in FIG. In other words, the engine amplitude peak can be attenuated as shown by the dotted line in FIG.

At the above engine speed, the electromagnetic actuator is driven to dampen the engine vibration as in the conventional case.

[0028]

FIG. 1 shows an active engine according to the present invention.
An embodiment of the mounting device is shown for the case of being applied to a four-cylinder large displacement diesel engine such as a small truck.

In this embodiment, an engine mount 3 composed of an electromagnetic actuator portion A and a liquid operation portion B (schematically shown in this figure) is provided between the engine 1 and the vehicle body 2, and the engine mount 3 is provided. A controller 4 is connected to the mount 3.

The controller 4 receives an engine rotation synchronizing pulse (an engine speed sensor is not shown) and gives an actuator driving circuit 41 for giving a control signal to the electromagnetic actuator portion A of the engine mount 3, and an engine rotation synchronizing pulse. ON / O of the switching valve 5 connected to an engine intake negative pressure source (not shown) such as a manifold
It is composed of an orifice control circuit 42 which gives an FF control signal.

Further, the orifice control circuit 42 detects the engine speed from the engine speed synchronizing pulse, and a rotation speed detection circuit 421, and whether or not the orifice should be controlled from the engine speed detected by the rotation speed detection circuit 421. An orifice control determination circuit 422 that determines whether or not it is configured, and a relay circuit 423 that is driven based on the output signal of this determination circuit 422.

FIG. 2 shows a detailed view of the engine mount 3 schematically shown in FIG. 1, and FIG. 2 (1) shows a peak P1 shown in FIG. 9 in the engine speed during idle rotation. FIG. 2B shows a state for attenuating the peak P2 of the engine shake shown in FIG. 9 at an engine speed other than the idle revolution region shown by the diagonal lines in FIG. Shows.

That is, during idle rotation, the orifice control circuit 42 causes the switching valve 5 to operate as shown in FIG.
9 is turned on so that both the variable orifice portion b61 and the fixed orifice portion b62 are opened, liquid suction and discharge between the liquid chambers b1 and b2 is performed in both orifice portions b61 and b62, and the variable orifice portion b61 in FIG. Attenuate the indicated peak P1. At this time, at the fixed orifice portion b7, the liquid sucking / discharging operation is simultaneously performed and the peak P
It goes without saying that it contributes to the attenuation of 1. However, this fixed orifice portion b7 is not essential.

Further, when it is detected that the engine speed corresponds to the peak P2 as shown in FIG. 9 above the idle speed, the orifice control circuit 42 causes the switching valve 5 to operate as shown in FIG. 2 (2). The variable orifice portion b61 is closed by closing the fixed orifice portion b62.
Only the open state is opened to suck and discharge the liquid between the liquid chambers b1 and b2 at the fixed orifice portion b62 to attenuate the peak P1.

FIG. 3 is a diagram for explaining the control operation of the orifice portion shown in FIGS. 1 and 2, and FIG. 3 (1) shows an operating state at the time of idle rotation shown by hatching in FIG.
9 (2) shows an operating state other than during idle rotation and FIG.
The operating state when the engine speed of the peak P2 shown in FIG.

The fixed orifice portion b62 and the variable orifice portion b61 are connected by the cylinder 10 and divide the liquid chambers b1 and b2. The fixed orifice portion b62 has no opening / closing portion, but the variable orifice portion b
A cylinder 10 is provided inside the cylinder 61, and a piston 11 is further provided inside the cylinder 10 so as to be moved left and right in the drawing by a spring 12.

The variable orifice portion b61 is open in the case of (1) in the figure, and the variable orifice portion b61 is closed in the case of (2) in the figure.

FIG. 4 is a flow chart for explaining the operation of the orifice control circuit, and the operation of the embodiment of the present invention shown in FIGS. 1 to 3 will be described below with reference to this flow chart.

First, the controller 4 turns on the engine key.
After confirming (step S1), the engine speed is read from a sensor (not shown) to detect the speed.
Is detected (step S2).

Next, this engine speed is in the idle speed range (about 550 rpm to 600 rpm) as shown by the diagonal lines in FIG.
rpm) is determined by the determination circuit 422 (step S3).

If the result of this determination is that it is during idle rotation, the relay circuit is turned on (step S4). As a result, the switching valve 5 is turned on.
(Step S5).

When the switching valve 5 is turned ON, the piston 11 in the cylinder 10 is pulled by the negative pressure from the engine vacuum portion 7 as a negative pressure source, and the spring 12 contracts to open the passage of the variable orifice portion b61. Become. Therefore, the liquid in the liquid chamber b1 passes through the variable orifice portion b61 and the fixed orifice portion b62 to perform suction / discharge operation with the liquid chamber b2.

The tuning corresponding to the engine shake at the time of idle rotation is performed by adjusting the supporting spring constant k ₀ in the above equation (1) to a dynamic spring matched to a frequency which is a problem in the cross-sectional area of the liquid chamber or the area of the orifice. Set a constant. In practice, the method realized by changing the cross-sectional area of the orifice is easy.

Then, for example, the fixed orifice portion b62
One of the variable orifice portion b61 and the variable orifice portion b61 is set to the peak P1 shown in FIG. Alternatively, the fixed orifice portion b62 is set to the peak P2,
A combination of the orifice portions b61 and b62 may be set as the peak P1.

Therefore, by opening the variable orifice portion b61 and the fixed orifice portion b62 during the set idle rotation, the dynamic spring constant of the variable orifice portion b61 is reduced and the rubber is just softened.
The peak P1 of 1 is attenuated as shown by the dotted line in FIG.

On the other hand, when the engine speed is increased by stepping on the accelerator, and as a result, it is found in step S3 that the engine speed is higher than the idle speed range, the engine speed is set to correspond to the peak P2 shown in FIG. It is determined whether the engine speed is equal to or lower than the engine speed (around 1000 rpm) (step S6).

As a result, when it is found that the engine speed is below the upper limit idle engine speed, the relay circuit 423
Is turned off (step S7), and the switching valve 5
Is turned off (step S8), and the process returns to step S2. When it is found that the engine speed is equal to or higher than the upper limit idle engine speed, the electromagnetic actuator unit A is controlled in the same manner as the above-mentioned conventional example.

Therefore, the variable orifice portion b61 is closed,
The suction and discharge of the liquid through the variable orifice portion b61 is stopped, and the suction and discharge of the liquid is performed only through the fixed orifice portion b62. Since the dynamic spring constant of the engine mount 3 by only the fixed orifice portion b62 is set so as to correspond to the engine speed of the peak P2 in FIG. 9, the engine vibration amplitude is reduced as shown by the dotted line in FIG. It

Although the drive control of the electromagnetic actuator portion A by the actuator drive circuit 41 is not performed at each of the above engine speeds, the engine speed (1000 rpm) or more, which is the upper limit value in the idle speed range, is determined in step S6. When it is found that the engine vibration amplitude is small and the amplitude required for the engine mount is low, the actuator drive circuit 41 follows the engine rotation synchronizing pulse in the same manner as in the above-described conventional example, and the electromagnetic wave of the engine mount 3 is detected. If you drive the actuator A,
A stroke that can cancel the input amplitude almost completely can be demonstrated. Theoretically, the explosion primary component of the mount axial component can be canceled almost completely.

[0050]

As described above, according to the active engine mount device of the present invention, the orifice is composed of the fixed orifice portion and the variable orifice portion having a specific cross-sectional area which gives the dynamic spring constant of the engine mount. The engine shake is different by opening and closing the variable orifice part using the ON / OFF valve to suck and discharge liquid without driving the electromagnetic actuator part depending on whether the engine is idling or less than the upper limit engine speed. Since the peak is attenuated, the following unique effects can be obtained.

(1) Shakes near the idle can be greatly reduced. It can handle multiple peaks up to around 1000 rpm, and can significantly reduce vibration. (2) Since the idle vibration is directed in the liquid actuating part, the actuator does not have to deal with low frequencies and large amplitudes near the idle, so the size and weight can be reduced, the layout can be easily established, and the narrow vehicle width is narrow. It can also be applied to vehicle types such as small trucks of the type, RV vehicles, etc., where the engine and frame are closely spaced. (3) It is also effective when a torque reaction force is applied, such as when an A / T vehicle or the D range brake is stopped. (4) It is also effective for cranking vibration and shaking during key-off.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of an active engine mount device according to the present invention.

FIG. 2 is a cross-sectional view for explaining the operation of the variable orifice portion in the engine mount used in the present invention.

FIG. 3 is a diagram for specifically explaining the operation of the variable orifice portion.

FIG. 4 is an operation flowchart of an orifice control circuit in the controller used in the present invention.

FIG. 5 is a graph chart for comparing effects of the present invention and a conventional example.

FIG. 6 is a dynamic characteristic map of rubber used conventionally.

FIG. 7 is a sectional view showing a configuration example of an engine mount in a conventional example.

FIG. 8 is a vibration amplitude characteristic diagram of the engine.

FIG. 9 is a vibration characteristic diagram of the engine shake observed on the floor of the passenger compartment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 engine 2 vehicle body 3 engine mount A electromagnetic actuator part B liquid operation part 4 controller 41 actuator drive circuit 42 orifice control circuit b1 to b5 liquid chamber b61 variable orifice part b62 fixed orifice part 5 switching valve A considerable part is shown.

Claims (1)

[Claims] 1. An engine mount comprising an electromagnetic actuator part provided between an engine and a vehicle body and a liquid actuating part having an orifice between liquid chambers, and the electromagnetic actuator part based on a rotation synchronizing signal of the engine. In an active engine mount device configured to drive an engine vibration in the liquid operation part, the orifice being variable with a fixed orifice part having a specific cross-sectional area that gives a dynamic spring constant of the engine mount. When the controller detects the idling speed from the engine rotation synchronizing signal, it is turned on by a switching valve without driving the electromagnetic actuator.
/ OFF valve is opened to open the variable orifice part to suck and discharge the liquid together with the fixed orifice part to attenuate the peak of engine shake during idle rotation and from the idle speed to the upper limit value of the idle speed range. When the engine speed is detected, the switching valve closes the ON / OFF valve to close the variable orifice section and suck and drain the liquid only by the fixed orifice section, so that another engine shake other than during idle rotation can be performed. An active engine mounting device that features attenuating peaks.