JP2000255277A - Mounting device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mounting device of an internal combustion engine which can effectively reduce transmission of engine vibration to supports even in the case of an internal combustion engine whose combustion characteristic varies during operation. SOLUTION: An internal combustion engine E which is switched between lean combustion and stoichiometric air/fuel ratio combustion is suspended and supported on a vehicle body B via an active control mount(ACM) 30. The ACM 30 reduces transmission of engine vibration to the vehicle body B by means of braked vibration output by the supply and discharge of negative pressure based on the turning on/off of a vacuum selector valve(VSV) 20. An electronic control unit 24 calculates the on/off period of the VSV 20 on the basis of the fuel injection quantity and speed of the internal combustion engine E so as to control the braked vibration generated by the ACM 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension system for an internal combustion engine which suspends and supports an internal combustion engine on a vehicle body or other supports. The present invention relates to the implementation of a suitable control structure.

[0002]

2. Description of the Related Art Conventionally, as a suspension device for an internal combustion engine of this type, for example, a device described in Japanese Patent Application Laid-Open No. 10-331663 is known. In this suspension device, the active control mount (A
The diaphragm is displaced by the supply and discharge of the intake negative pressure to and from the air chamber provided in the CM) to generate a braking vibration.

In this suspension system, the generated braking vibration is controlled while switching the control map according to the operating conditions of the internal combustion engine (switching on / off of the air conditioner). By controlling the braking vibration in this way, it becomes possible to generate an appropriate braking vibration every time in accordance with a change in the engine vibration caused by a change in the load of the engine.

By the way, even when the control is performed by simply switching the control map in accordance with the operating conditions of the internal combustion engine, the transmission of the engine vibration is limited as long as the operation is performed only when the operating state of the internal combustion engine changes little, such as during idling. It can be suppressed appropriately. However, during normal operation in which the operating state of the internal combustion engine fluctuates greatly, the manner of occurrence of engine vibration also fluctuates in a complicated manner. Therefore, simply switching the control map in accordance with the operating conditions makes it possible to appropriately deal with such fluctuations in engine vibration. It is difficult to obtain a proper braking vibration.

Conventionally, instead of switching the control map according to the operating conditions of the internal combustion engine, it has been considered to control the braking vibration based on the intake air amount which is a parameter reflecting the load state of the engine. I have. If the braking vibration is controlled in this manner, not only a change in the engine load for each operating condition during the idling operation, but also an appropriate braking vibration can be obtained even in response to the above-mentioned severe fluctuation in the engine load during the normal operation. Will be obtained.

[0006]

By controlling the braking vibration on the basis of the intake air amount in this way, even if the engine vibration changes due to the fluctuation of the engine load, the supporting body of the engine vibration (in-vehicle internal combustion engine) can be used. (In the case of an engine, transmission to the vehicle body) can be effectively suppressed.

However, in the case of an internal combustion engine in which the combustion characteristics such as the air-fuel ratio, the compression ratio, the expansion ratio, and the fuel pressure during direct injection in a cylinder change during operation, as described above, the internal Even if the braking vibration is controlled, an appropriate vibration reduction effect may not be obtained.

For example, in an internal combustion engine that switches between combustion at a stoichiometric air-fuel ratio and combustion at a lean air-fuel ratio, the combustion at the stoichiometric air-fuel ratio and the combustion at the lean air-fuel ratio are performed even if the intake air amount is the same. Since the output torque is different between and, the mode of occurrence of engine vibration accompanying the torque generation also changes naturally. Therefore, even if the control is performed based on the intake air amount, it is not always possible to obtain an appropriate braking vibration corresponding to the engine vibration.

As described above, if the combustion characteristics are different, the correspondence between the amount of intake air and the manner in which engine vibrations occur also changes. Therefore, in an internal combustion engine whose combustion characteristics change during operation, the amount of intake air is based on the amount of intake air. It is difficult to obtain an appropriate braking vibration according to the vibration of the engine alone.

The present invention has been made in view of the above circumstances, and has as its object to effectively reduce the transmission of engine vibration to a support even in an internal combustion engine whose combustion characteristics change during operation. It is an object of the present invention to provide a suspension device for an internal combustion engine that can perform the suspension.

[0011]

The means for achieving the above object and the effects thereof will be described below. The invention according to claim 1 is a suspension device for an internal combustion engine, which suspends and supports an internal combustion engine whose combustion characteristics change during operation on a support, wherein the suspension device generates a braking vibration against the vibration of the internal combustion engine. And a control means for controlling the braking vibration generation mode of the vibration reduction mechanism based on the output torque of the engine.

According to the above configuration, by using the output torque of the engine, which is a direct cause of the engine vibration, for the drive control of the vibration reducing mechanism, it is possible to appropriately estimate the generation mode of the engine vibration and reduce the braking vibration. You will be able to control it. For this reason, even when the combustion characteristic is changed during operation and the generation mode of the engine vibration changes, the braking vibration can be appropriately adjusted in accordance with the engine vibration. Therefore, even in an internal combustion engine whose combustion characteristics change during operation, transmission of engine vibration to the support can be reduced more efficiently.

According to a second aspect of the present invention, there is provided a suspension system for an internal combustion engine in which an internal combustion engine, whose combustion characteristics change during operation, is supported on a support body, wherein a braking vibration against the vibration of the internal combustion engine is generated. A vibration reduction mechanism that reduces transmission of the vibration of the engine to the support, and control means that controls the braking vibration generation mode of the vibration reduction mechanism based on an operation state amount reflecting an output torque of the engine. The main point is to provide

According to the above configuration, by controlling the braking vibration using the engine operating state quantity reflecting the output torque, the generation mode of the engine vibration is appropriately estimated irrespective of the change in the combustion characteristics to reduce the braking vibration. You will be able to control it. Therefore, even in an internal combustion engine whose combustion characteristics change during operation,
The transmission of the engine vibration to the support can be reduced more efficiently.

The invention according to claim 3 is the same as the invention according to claim 2.
In the suspension system for an internal combustion engine described in (1), the gist is that the operation state quantity referred to by the control means is a fuel injection amount of the engine.

According to the above configuration, the braking vibration is adjusted almost directly using the fuel injection amount reflecting the output torque of the internal combustion engine regardless of the change in the combustion characteristics. Therefore, even when the combustion characteristics of the engine change, appropriate braking vibration corresponding to engine vibration can be obtained, and transmission of engine vibration to the support can be reduced more efficiently. Become.

The invention described in claim 4 is the same as the claim 2.
In the suspension system for an internal combustion engine described in the item (1), the gist is that the operation state amount referred to by the control means is a fuel injection amount and an engine speed of the engine.

According to the above configuration, the braking vibration is controlled using the fuel injection amount and the engine speed. By using the fuel injection amount and the engine speed together, it is possible to more accurately estimate the output torque of the internal combustion engine and its generation timing. For this reason, more appropriate braking vibration can be obtained, and transmission of engine vibration to the support can be reduced more efficiently.

The invention described in claim 5 is the third invention.
Alternatively, in the suspension system for an internal combustion engine described in 4, the operating state quantity of the engine referred to by the drive control means further includes an ignition timing of the engine.

According to the above configuration, the braking vibration is also adjusted by the ignition timing which directly affects the generation timing of the output torque of the engine. For this reason, more appropriate braking vibration according to the engine vibration can be obtained as the braking vibration, and transmission of the engine vibration to the support can be reduced more efficiently.

In particular, when the ignition timing is changed irrespective of the engine speed or the fuel injection amount, such as when knock control is performed, the timing of the occurrence of the braking vibration is optimized by using the ignition timing. As a result, appropriate braking vibration can be obtained.

The invention described in claim 6 is the same as the invention described in claim 3.
6. The suspension system for an internal combustion engine according to any one of claims 1 to 5, wherein the operation state amount of the engine referred to by the drive control means further includes an intake air amount of the engine. .

If the amount of intake air is different even if the fuel injection amount is constant, that is, if the air-fuel ratio is different, the combustion speed of the air-fuel mixture changes, so that the timing of generating the output torque of the engine also changes. According to the above configuration, the mode of occurrence of the braking vibration is also adjusted by the amount of intake air, so that a change in the timing of occurrence of the engine vibration caused by such a change in the combustion speed is absorbed, and a more efficient engine vibration support Transmission to the user.

[0024] Further, the invention described in claim 7 is based on claim 1.
The suspension of the internal combustion engine according to any one of claims 1 to 6, wherein the control means controls a phase of a braking vibration generated from the vibration reducing mechanism.

According to the above configuration, the phase of the braking vibration is adjusted according to the output torque. For this reason, it is possible to generate the braking vibration in a more appropriate phase in response to the change in the phase of the engine vibration accompanying the change in the combustion characteristic of the engine, and to more effectively transmit the engine vibration to the support. It can be reduced.

The invention described in claim 8 is the first invention.
The suspension of the internal combustion engine according to any one of claims 1 to 7, wherein the drive control means controls the magnitude of braking vibration generated from the vibration reduction mechanism. is there.

According to the above configuration, the magnitude of the braking vibration is adjusted according to the output torque of the engine. Therefore, it is possible to generate braking vibration having a more appropriate magnitude in response to a change in the magnitude of the engine vibration accompanying a change in the combustion characteristic of the engine, and to more effectively transmit the engine vibration to the support. Can be reduced.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment Hereinafter, a first embodiment of a suspension system for an internal combustion engine according to the present invention will be described in detail.

First, the configuration of an internal combustion engine to which the suspension of the present embodiment is applied will be described with reference to FIG.
FIG. 1 shows a schematic structure of a vehicle-mounted internal combustion engine suspended and supported on a vehicle body by a suspension device of the present embodiment.

The internal combustion engine E to which the present embodiment is applied is an in-line four-cylinder automobile gasoline engine.
The first cylinder # 1 to the fourth cylinder # 4 are provided with four cylinders. Further, the internal combustion engine E is operated while switching between combustion at the stoichiometric air-fuel ratio and combustion at the lean air-fuel ratio in accordance with the operating state of the engine E. On the other hand, an automobile equipped with an internal combustion engine E to which the present embodiment is applied employs an electronically controlled automatic transmission.

As shown in FIG. 1, a throttle valve 11 is provided in an intake passage 10 of the internal combustion engine E.
The throttle valve 11 is opened and closed by a throttle drive device 12 that is driven and controlled by an electronic control unit 24, and adjusts the amount of intake air passing through the intake passage 10 even during idle operation of the engine E. When the internal combustion engine E is burning at the stoichiometric air-fuel ratio, the throttle valve 11 is driven to open and close in accordance with the amount of depression of the accelerator pedal 17. On the other hand, during operation in which combustion is performed at the lean air-fuel ratio, the opening is set to be larger than the opening corresponding to the depression amount of the accelerator pedal 17 during combustion at the stoichiometric air-fuel ratio.

The throttle valve 1 in the intake passage 10
An injector 15 for injecting fuel is provided on the downstream side of 1. The electronic control unit 24 controls the fuel injection amount (fuel injection time) based on the intake air amount, the engine speed, and the like.
Is calculated, and the driving of the injector 15 is controlled in accordance with the calculated fuel injection amount.

The fuel injected from the injector 15 is ignited by an igniter 16. The igniter 16 supplies a current to the ignition coil at a timing set based on the ignition timing calculated by the electronic control unit 24 according to the operation state of the internal combustion engine E, and ignites the fuel through the ignition plug.

The electronic control unit 24 includes an internal combustion engine E and a vehicle body B.
The operating state and operating conditions of the engine E are detected based on the detection results of various sensors provided at various locations. Hereinafter, these various sensors will be described.

First, an air flow meter S01 is provided upstream of the throttle valve 11 in the intake passage 10. The air flow meter S01 is connected to the intake passage 10
Detecting the amount of intake air introduced into the internal combustion engine E through the
An output signal corresponding to the detected intake air amount is output to the electronic control unit 24.

A crank angle sensor S02 for detecting the rotational phase of the crankshaft 18 is provided around the crankshaft 18, which is the engine output shaft. The crank angle sensor S02 is composed of an electromagnetic pickup, detects signal teeth formed on the outer periphery of a rotor 19 provided at one end of the crankshaft 18, and outputs a pulse signal (NE signal). The signal teeth of the rotor 19 are partially missing. The reference rotational phase of the crankshaft 18 is detected from the detection signal corresponding to the missing teeth, and the accurate top dead center of each of the cylinders # 1 to # 4 is determined. You can figure out. The electronic control unit 24 grasps the rotation phase of the crankshaft 18 and the engine speed by counting the pulse-like signals output from the crank angle sensor S02.

Further, the throttle drive device 12 includes:
A throttle opening sensor S03 is provided. The electronic control unit 24 detects the opening of the throttle valve 11 from the output signal of the throttle opening sensor S03.

Further, output signals of the vehicle speed sensor S04 and the accelerator opening sensor S06 are also input to the electronic control unit 24. The electronic control unit 24 calculates the vehicle speed at that time from the output signal of the vehicle speed sensor S04,
The amount of depression of the accelerator pedal 17 is detected from the output signal 06. As described above, the detected depression amount of the accelerator pedal 17 is reflected on the operation amount of the throttle valve 11.

The output signal of the shift position sensor S05 provided in the automatic transmission is input to the electronic control unit 24. From the output signal of the shift position sensor S05, the electronic control unit 24 determines whether the shift position is in the "N" range (neutral range) and the "P" range (parking range), or in the other range. Is detected. In the following description, when the shift position is in the “N” and “P” ranges, the shift position is in the “N” range, and when the shift position is in the other ranges, the “D” range (drive
Range) time.

In an automobile equipped with an automatic transmission, in the "D" range, a slight torque is transmitted from the internal combustion engine E to the axle even when the vehicle body is stopped. Therefore, the load on the internal combustion engine E during the idling operation is slightly larger in the “D” range than in the “N” range. Therefore, the electronic control unit 24 sets the idle speed higher in the "D" range than in the "N" range.

In addition, output signals from other various sensors S00 are input to the electronic control unit 24. The electronic control unit 24 is controlled by these other sensors S00.
Detects the operating state and operating conditions of the internal combustion engine E, such as the temperature state of the engine cooling water, the on / off state of the air conditioner, and the occurrence of knocking.

The internal combustion engine E configured as described above
As shown in FIG. 1, a plurality of (two in FIG. 1)
It is suspended and supported by a vehicle body B as its support via an active control mount (ACM) 30.

Next, the specific structure of the ACM 30 will be described with reference to FIG. FIG. 2 is a sectional view showing the internal structure of the ACM 30. As shown in FIG.
M30 includes a main body case 32 fixed to the vehicle body B and formed in a tubular shape. An elastic member 39 made of an elastic material such as rubber is fitted into the upper inside of the main body case 32. On the upper part of the main body case 32, a connecting member 31 connected to the main body case 32 via the elastic member 39 is movably arranged. This connecting tool 31
Is fixed to the internal combustion engine E.

On the other hand, the inside bottom of the main body case 32 is filled with a cushioning member 33 made of an elastic material such as rubber. In the space between the elastic member 39 and the cushioning member 33 inside the main body case 32, liquid chambers 40 and 41 filled with a fluid such as oil are formed.
The liquid chambers 40 and 41 are divided into upper and lower parts by an isolation member 34 made of an elastic body such as rubber fitted inside the main body case 32. These two liquid chambers 40 and 4
1 are connected by a small-diameter passage (not shown),
Fluid can flow between the two liquid chambers 40 and 41.

A sheet-like diaphragm 35 is provided on the upper surface of the separating member 34 that partitions the two liquid chambers 40 and 41. The diaphragm 35 is provided with a fixture 36.
The edge portion is fixed to the isolation member 34 by the above, and an air chamber 37 is formed between the diaphragm 35 and the upper surface of the isolation member 34. A supply / discharge passage 23 is connected to the air chamber 37, and the volume of the air chamber 37 is expanded or reduced by supplying and discharging air into the air chamber 37 through the supply / discharge passage 23. become.

The supply / discharge passage 23 connected to the air chamber 37
Is a negative pressure switching valve (VSV) 20 as shown in FIG.
It is connected to the. The VSV 20 is further connected to the negative pressure passage 2.
1 and the atmospheric pressure passage 22 are connected to the intake passage 10 on the downstream and upstream sides of the throttle valve 11, respectively.

The VSV 20 has an electromagnetic solenoid, and is turned on / off in accordance with the presence or absence of a voltage applied to the electromagnetic solenoid. Then, according to the on / off operation, one of the negative pressure passage 21 and the atmospheric pressure passage 22 is selectively communicated with the supply / discharge passage 23.
The intake air flowing upstream of the throttle valve 11 in the intake passage 10 to which the atmospheric pressure passage 22 is connected has an atmospheric pressure. The intake air flowing downstream of the throttle valve 11 in the intake passage 10 to which the negative pressure passage 21 is connected has a negative pressure due to the throttle valve 11 being throttled.

Next, referring to FIG. 1 and FIG.
The operation of M30 will be described. In the VSV 20, when a voltage is ignited to the electromagnetic solenoid, that is, VSV
When the V20 is turned on, the supply / discharge passage 23 and the negative pressure passage 21 communicate with each other. At this time, ACM30
From the air chamber 37, air is discharged by the negative pressure on the downstream side of the throttle valve 11, and the volume thereof is reduced. On the other hand, when the application of the voltage to the electromagnetic solenoid of the VSV 20 is stopped, that is, when the VSV 20 is turned off, the supply / discharge passage 23 and the atmospheric pressure passage 22 are connected. At this time, the air chamber 37 of the ACM 30
Air is supplied by the atmospheric pressure on the upstream side of the throttle valve 11, and the volume of the air is increased. The ON / OFF operation of the VSV 20, that is, the presence or absence of a voltage applied to the electromagnetic solenoid is determined by the electronic control unit 24.
Is controlled by

Incidentally, the engine vibration of the internal combustion engine E is input to the ACM 30 through the connecting member 31. When the elastic member 39 connected to the connecting member 31 is deformed by the vibration thus input, the volume of the liquid chamber 40 formed above the separating member 34 changes, and the fluid filled in each of the liquid chambers 40 and 41 is changed. Come and go through the small-diameter passage. The deformation of the buffer member 33, the isolation member 34, the elastic member 39, and the like, and the liquid chambers 40, 4
Transmission of engine vibration from the internal combustion engine E to the vehicle body B is suppressed through the flow of the fluid filled in the internal combustion engine 1.

The properties of the ACM 30 as a cushioning material,
That is, the spring characteristics and the damping characteristics are determined by the air chamber 3
7 can be made variable by changing its volume based on the supply and exhaust of air to and from the air conditioner 7. Incidentally, in the ACM 30 of the present embodiment, by keeping the VSV 20 in the ON state, the amount of air in the air chamber 37 becomes “0”,
The CM 30 is the hardest (hardest) as a cushioning material. In addition, by holding the VSV 20 in the off state, the amount of air in the air chamber 37 is maximized, and the ACM 30 becomes the softest (softest) as a cushioning material. As described above, by appropriately varying the characteristics of the ACM 30 as a cushioning material in accordance with the operation state of the internal combustion engine E, the transmission of vibration to the vehicle body B is appropriately suppressed in accordance with a change in the mode of occurrence of engine vibration. Will be able to

In the ACM 30 according to the present embodiment, not only the characteristics of the cushioning material are made variable as described above, but also the ACM 30 itself generates a braking vibration in accordance with the engine vibration. In addition, transmission of engine vibration to the vehicle body B can be suppressed. That is, in the ACM 30, the above-described braking vibration is generated by repeatedly applying a voltage to the electromagnetic solenoid of the VSV 20 synchronously and repeatedly expanding / reducing the volume of the air chamber 37. Then, by appropriately controlling the generated braking vibration in accordance with the engine vibration, transmission of the engine vibration to the vehicle body B is suppressed more efficiently.

Next, the VSV by the electronic control unit 24
20 will be described in detail with reference to FIGS. First, a configuration of a control device for mainly driving and controlling the VSV 20 will be described based on a functional block diagram shown in FIG.

In FIG. 3, the electronic control unit 2
The rotation speed calculation unit P01, the fuel injection amount calculation unit P02, the ignition timing calculation unit P03, and the VSV drive timing calculation unit P04 that constitute the fourth unit 4 are actually configured as a part of an arithmetic and logic operation circuit centered on a microcomputer. ing. Also,
A VSV drive circuit P0 also constituting the electronic control unit 24
5 is based on the time information set to a predetermined output port of the microcomputer.
0 is a circuit for controlling the drive.

As described above, an internal combustion engine E to which the suspension system of the present embodiment is applied and a vehicle on which the engine E is mounted are provided with an operating state and an operating condition for detecting the operating state of the engine E. Various sensors are provided. As shown in FIG. 3, the air flow meter S01 outputs a signal corresponding to the amount of intake air passing through the intake passage 10 to the crank angle sensor S0.
2 is a pulse signal (NE signal) corresponding to the detection signal of the signal teeth of the rotor 19 provided on the crankshaft 18;
The vehicle speed sensor S04 outputs a signal corresponding to the vehicle speed of the automobile equipped with the internal combustion engine E, and the shift position sensor S05 outputs a signal corresponding to the shift position (“N” range or “D” range) of the transmission. .

Each of the control units P01 to P04 executes processing related to the drive control of the VSV 20 based on the output signals of these various sensors. Hereinafter, each of these control units P01 to P01
The processing executed by the program 04 will be described.

First, the engine speed calculation unit P01 calculates the engine speed based on the NE signal output from the crank angle sensor S02. Further, the fuel injection amount calculation unit P02 calculates the fuel injection amount based on the engine speed calculated by the rotation speed calculation unit P01, the intake air amount detected by the air flow meter S01, and the like. Although not shown in FIG. 3, the electronic control unit 24 drives the injector 15 (FIG. 1) to open the injector 15 (FIG. 1) through the corresponding drive circuit for a time corresponding to the fuel injection amount calculated here.

On the other hand, the ignition timing calculation section P03 calculates the ignition timing based on the engine speed, the intake air amount and the like. This is also not shown in FIG.
Is based on the ignition timing calculated here.
An ignition signal is output to (FIG. 1), and ignition is performed through the ignition plug at the calculated timing.

The VSV drive timing calculating section P04 includes a VSV on time (a time from the reference time to a start of voltage application to the electromagnetic solenoid) T0 and V0 for setting a time for switching the VSV 20 on / off operation.
The SV off time (time from the reference time to the stop of the voltage application to the electromagnetic solenoid) T1 is calculated.
The times T0 and T1 are determined by the engine speed and the fuel injection amount calculated by the rotation speed calculation unit P01 and the fuel injection amount calculation unit P02, respectively, and further by the vehicle speed and the shift position sensor S05 detected by the vehicle speed sensor S04. The calculation is performed based on engine operating conditions such as the detected shift position (“N” range or “D” range). This V
Details of the calculation processing performed by the SV drive timing calculation unit P04 will be described later.

The VSV drive circuit P05 uses the VSV
The time T calculated by the V drive timing calculation unit P04
The VSV 20 is driven by switching the manner of applying a voltage to the electromagnetic solenoid of the VSV 20 based on 0 and T1.

Subsequently, these VSV drive timing calculation units P0
4 and a specific driving mode of the VSV 20 by the VSV driving circuit P05 will be described with reference to FIG. The time chart of FIG. 4 shows the transition of the voltage applied to the VSV 20 to the electromagnetic solenoid.

As shown in FIG. 4, the VSV drive timing calculating section P04 that has calculated the VSV on time T0 and the VSV off time T1 is a target cylinder (first cylinder # in FIG. 4).
1) The VSV ON times T0 and V
The SV off time T1 is set. As a result, the VSV drive circuit P05 uses these VSV on-time T1 and VSV
The voltage applied to the electromagnetic solenoid is started when the off-time T1 is set, that is, when the VSV on-time T0 elapses from the time when the crankshaft 18 is located at the top dead center phase of the cylinder. The internal combustion engine E to which the suspension device of the present embodiment is applied is an in-line four-cylinder type, and the cylinders # 1 and # 4 each time the rotational phase of the crankshaft 18 advances by 180 ° CA (crank angle). ,
Top dead center is set in the order of # 2 and # 3.

Thereafter, the VSV drive circuit P05 keeps applying a voltage to the electromagnetic solenoid after the top dead center of each of the cylinders # 1 to # 4 until the VSV off time T1 elapses. Therefore, during this period, ie, after top dead center,
During the period from when the VSV on time T0 elapses to when the VSV off time T1 elapses, air is exhausted from the air chamber 37 of the ACM 30, and the volume of the air chamber 37 is reduced.

Then, the VSV drive circuit P05 sets the VSV off time T1 after the top dead center, and
The application of the voltage to the electromagnetic solenoid 20 is stopped. Then, after the top dead center of the next cylinder (fourth cylinder # 4 in FIG. 4), the VSV drive circuit P05 maintains this voltage application stopped state until the VSV on time T0 elapses. become. During this period, the air chamber 37 of the ACM 30 is used.
Is supplied with air, and the volume of the air chamber 37 is expanded.

By repeating the supply and discharge of air to and from the air chamber 37 in this manner, the diaphragm 35 is moved up and down, and braking vibration is generated. Further, by changing the VSV on time T0 and the VSV off time T1, the timing and the magnitude of this braking vibration (diaphragm 35
(The amount of movement and the degree of movement to the maximum movement position) are adjusted. By appropriately adjusting the braking vibration in accordance with the generation mode of the engine vibration, that is, the generation timing and the magnitude of the engine vibration, the transmission of the engine vibration to the vehicle body B is reduced.

Next, the processing procedure of the VSV drive timing calculation unit P04 for calculating the VSV on time T0 and the VSV off time T1 will be described with reference to FIGS. FIG.
9 is a flowchart illustrating a procedure of a series of processes executed by the VSV drive timing calculation unit P04 (actually as part of the internal combustion engine control performed by the electronic control unit 24).

As shown in FIG. 5, the VSV drive timing calculating section P04 calculates the output signal of each sensor at that time from
Information on the vehicle speed, engine speed, shift position, and the like is obtained (step S10).

Then, the VSV drive timing calculation section P04 determines the current operating condition of the internal combustion engine E based on the information (steps S11 to S13). Here, it is determined from the vehicle speed and the engine speed whether the internal combustion engine E is in the high-speed operation, the medium-low speed operation, or the idling operation. In the present embodiment, when the vehicle speed is 50 km / h or more, it is determined that the vehicle is driving at high speed (step S1).
1). If the vehicle speed is less than 50 km / h, 3 km / h or more, or if the engine speed is 1000 rpm or more even when the vehicle speed is less than 3 km / h, it is determined that the vehicle is running at low speed (step S12). , S13). Strictly speaking, the medium-to-low-speed driving here includes the case where the vehicle is running at a low speed and the case where the engine speed is not sufficiently reduced even when the vehicle is running at a low speed or while the vehicle is stopped. The case where it cannot be considered as driving is included.

Further, when the vehicle speed is less than 3 km / h and the engine speed is less than 1000 rpm, it is determined that the engine is idling (step S13). After determining the operating conditions of the internal combustion engine E in this way, the VSV drive timing calculation unit P04 calculates a control duty ratio command value and a control phase command value, which are drive control parameters of the VSV 20, according to each operating condition.

Here, the control duty ratio command value is:
This is a parameter representing the ratio of the period during which the VSV 20 is turned on, and in the present embodiment, the period from the top dead center of one cylinder to the top dead center of the next cylinder, that is, the crankshaft 18.
Shows the ratio of the ON operation period to the period during which the motor rotates 180 ° CA.

On the other hand, the control phase command value is VSV
This is a parameter corresponding to the time when the voltage application to the electromagnetic solenoid 20 starts, that is, the ON operation time of the VSV 20, and here, the rotation of the crankshaft 18 from the top dead center of the target cylinder until the voltage application starts. Angle (crank angle).

In the above-described operation condition determination, when it is determined that the vehicle is operating at high speed, the VSV drive timing calculation unit P04
The control duty ratio command value is set to 0% (step S1
4), the control phase command value is set to 0 ° CA (step S15)
Set each. If it is determined that the vehicle is running at low speed, the control duty ratio command value is set to 100% (step 16), and the control phase command value is set to 0 ° CA (step S1).
7) Set each.

On the other hand, if it is determined that the engine is idling, a control duty ratio command value and a control phase command value are set according to the operating state of the internal combustion engine E in the following procedure (step S20). ).

The processing procedure for calculating the control command value in the case of the idling operation will be described below with reference to the flowchart of FIG. If it is determined that the vehicle is idling, the VSV
The drive timing calculation unit P04 firstly detects the shift position sensor S
It is determined whether the current shift position is in the “N” range or the “D” range based on the output signal 05 (step S201).

When the shift position is in the "N" range, the VSV drive timing calculating section P04 sets the control duty ratio command value based on the control map M01 shown in FIG. 7A (step S202) and returns to FIG. The control phase command value is set based on the control map M03 shown in FIG.
Set 3) respectively. On the other hand, when the shift position is in the “D” range, the control map M0 shown in FIG.
(Step S20).
4) The control phase command value is set to (step S205) based on the control map M04 shown in FIG. 8B. Note that these control maps M01 to M04 include:
The above-described rotation speed calculation unit P01 and fuel injection amount calculation unit P02
The control phase command value or the control duty ratio command value corresponding to the engine speed and the fuel injection amount calculated in is stored in advance.

Incidentally, as described above, when the shift position is in the "N" range (actually, the "P" range or "N" range), the shift position is in the "D" range ("P" range or "N" range). (A shift position other than the shift position), the load applied to the internal combustion engine E is different, and the manner of occurrence of engine vibration is also different. Here, a control map is selectively used for each shift position so that an appropriate control command value can be set according to the difference in the generation mode of the engine vibration. Note that in the present embodiment, as is apparent from the control maps M01 to M04 shown in FIGS.
The control duty ratio command value and the control phase command value are set to be larger in the “D” range than in the range, even at the same engine speed and fuel injection amount.

After setting the respective control command values according to the operating conditions of the internal combustion engine E at this time, the VSV drive timing calculating section P04 determines the VSV on-time T0 and the VSV based on the set control command values. The off time T1 is calculated (step S18 in the flowchart of FIG. 5).

The VSV on time T0 is calculated based on the following equation. That is, T0 = (180 ° CA rotation time) * (control phase command value [° CA]) / (180 [° C.
A]). In the above equation, the “time required for 180 ° CA rotation” is the time required for the crankshaft 18 to rotate from the top dead center of one cylinder to the top dead center of the next cylinder. The internal combustion engine E to which the present embodiment is applied is an in-line four-cylinder engine.
Corresponds to the time required for 180 ° CA rotation.

On the other hand, the VSV off time T1 is calculated based on the following equation. In other words, T1 = T0 + (180 ° CA rotation time) * (control duty ratio command value [%]) / (100
[%]).

Thus, the VSV drive timing calculation section P0
4 calculates the VSV on time T0 and the VSV off time T1. The VSV drive timing calculation unit P04 sets the VSV on time T0 and the VSV off time T1 in synchronization with the calculated VSV on time T0 and VSV off time T1, so that the VSV drive circuit P05 sets the VSV2 based on the set times T0 and T1.
As described above, the presence or absence of voltage application to the 0 electromagnetic solenoid is switched, and the ON / OFF operation mode of the VSV 20 is switched.

Incidentally, when the operating condition of the internal combustion engine E is determined to be high-speed operation, and the control phase command value is set to 0 ° CA and the control duty ratio command value is set to 0%, VSV
The ON time T0 becomes "0", and the VSV OFF time T1 also becomes "0". At this time, the voltage applied to the electromagnetic solenoid of the VSV 20 remains off from the top dead center of the target cylinder to the top dead center of the next cylinder, and the air chamber 37 of the ACM 30 is Air will continue to be supplied until the pressure reaches atmospheric pressure. Therefore, during high-speed operation, the amount of air in the air chamber 37 of the ACM 30 becomes maximum, and the ACM 30 becomes the softest (softest) as a buffer material.

When it is determined that the operating condition of the internal combustion engine E is a medium to low speed operation and the control phase command value is set to 0 ° CA and the control duty ratio command value is set to 100%, VS
The V-on time T0 is "0", and the VSV-off time T1 is the "time of 180 ° CA rotation". At this time, VS
The voltage applied to the electromagnetic solenoid V20 remains on from the top dead center of the target cylinder to the top dead center of the next cylinder. Therefore, the ACM at the time of middle and low speed operation
The air continues to be exhausted from the air chambers 37 of the 30 and the air volume in the air chambers 37 eventually becomes zero, and the ACM 30 becomes the hardest (hardest) as a buffer material.

When it is determined that the operating condition of the internal combustion engine E is high-speed operation or medium-low speed operation,
CM30 does not generate braking vibration, but simply
By switching the characteristics of the buffer member 30 itself according to the respective operating conditions, transmission of engine vibration to the vehicle body B is suppressed.

On the other hand, when it is determined that the operation condition of the internal combustion engine E is the idling operation, the VSV 20 is repeatedly turned on / off in a predetermined manner to generate a braking vibration, thereby causing the engine to vibrate. The transmission of the vibration to the vehicle body B is suppressed.

By the way, when the vehicle is idling while the vehicle is stopped or running at a very low speed, no or almost no traveling vibration is transmitted from the road surface, so that the occupant of the vehicle can easily experience the vibration transmitted from the internal combustion engine E. It is in. For this reason, during idle operation, the ACM30
By generating braking vibration, transmission of engine vibration to the vehicle body B is reduced more effectively than when the vehicle is running, thereby improving the ride comfort of the occupant.

The timing and magnitude of the occurrence of the braking vibration at this time are determined by the VSV on time T0 and the VSV off time T1. In this embodiment, as described above, each of these times T0 and T1
Is set mainly based on the fuel injection amount and the engine speed.

Incidentally, in the internal combustion engine in which the combustion at the lean air-fuel ratio and the combustion at the stoichiometric air-fuel ratio are switched during operation, such as the internal combustion engine E to which this embodiment is applied, The output torque of the engine E is different between combustion and combustion at the stoichiometric air-fuel ratio even if the intake air amount is the same.

However, even in the case where the combustion characteristics are different, the fuel injection amount almost directly reflects the output torque. Further, if the engine speed is used in addition to the fuel injection amount, the magnitude of the output torque of the internal combustion engine E and the generation timing thereof can be sufficiently estimated irrespective of the difference in combustion characteristics.

In this embodiment, by using the fuel injection amount and the engine speed as control parameters together, the braking vibration is reduced in accordance with the output torque of the internal combustion engine E which is a direct cause of engine vibration. I try to control.
Therefore, even when the combustion characteristics change, an appropriate braking vibration corresponding to the generation mode of the engine vibration can be generated, and the transmission of the engine vibration to the vehicle body B can be effectively suppressed.

As described above, according to the suspension system for an internal combustion engine of the present embodiment, the following effects can be obtained. (1) By controlling the braking vibration using the output torque of the internal combustion engine E directly related to the engine vibration and the fuel injection amount reflecting the generation time thereof and the engine speed as the control parameters, the mode of generating the engine vibration is improved. Appropriate braking vibration can be generated accordingly, and transmission of engine vibration to the vehicle body B can be effectively suppressed.

(2) Further, by using the fuel injection amount reflecting the output torque of the internal combustion engine E and the generation timing thereof and the engine speed as control parameters, a change in the generation mode of engine vibration caused by a difference in combustion characteristics is obtained. A suitable braking vibration can be generated which does not depend on the vibration. Therefore, even in an internal combustion engine in which combustion characteristics change, transmission of engine vibration can be appropriately suppressed.

(3) Further, by controlling the ON operation timing of the VSV 20, that is, the timing of the occurrence of the braking vibration from the fuel injection amount and the engine speed, the generation of the engine vibration due to the operating state of the internal combustion engine E and the combustion characteristics. According to the change of the timing, the braking vibration can always be generated at an appropriate timing.

(4) Similarly, by controlling the period during which the VSV 20 is turned on, that is, the magnitude of the braking vibration, from the fuel injection amount and the engine speed, the operating state and the combustion characteristics of the internal combustion engine E are controlled. It is possible to obtain a braking vibration having an appropriate magnitude according to a change in the magnitude of the engine vibration.

(5) Further, by using the fuel injection amount and the engine speed, which directly reflect the mode of occurrence of engine vibration, as control parameters, the control mode is changed according to the change in the combustion characteristics of the engine ( Appropriate braking vibration can be obtained without performing control map switching or correction for each combustion characteristic. Therefore, a sufficient effect of suppressing vibration transmission can be obtained even with a simple control structure as compared with the case where other operation state quantities such as the intake air quantity are used as control parameters.

In the present embodiment, a case has been described in which the suspension device is applied to an internal combustion engine that switches between combustion at a lean air-fuel ratio and combustion at a stoichiometric air-fuel ratio. And
By controlling the braking vibration using the fuel injection amount and the engine speed, the change in the output torque of the internal combustion engine due to the change in the combustion characteristics between combustion at a lean air-fuel ratio and combustion at a stoichiometric air-fuel ratio,
That is, it has been described that the transmission of the engine vibration can be effectively reduced without depending on the change of the generation mode of the engine vibration.

However, besides the case where the combustion at the lean air-fuel ratio and the combustion at the stoichiometric air-fuel ratio are switched as described above, for example, the fluctuation of the idling speed is suppressed, or the combustion is performed immediately after the engine is started or during the cold operation. Even when the fuel injection amount is temporarily increased in order to stabilize the state, the air-fuel ratio changes, and the combustion characteristics that change the generation mode of the engine vibration as described above occur. Further, not only the change in the air-fuel ratio, but also when the compression ratio, the expansion ratio, the fuel pressure at the time of in-cylinder injection, and the like are changed, the combustion characteristics change and the manner in which the engine vibration occurs changes.

In such a case, as in the above embodiment, the braking vibration is controlled by using the fuel injection amount and the engine speed which directly reflect the output torque of the engine without depending on the change in the combustion characteristics. Thus, transmission of engine vibration can be effectively suppressed.

(Second Embodiment) Next, a second embodiment which embodies a suspension system for an internal combustion engine according to the present invention will be described in detail with reference to FIGS.

In the present embodiment, the VSV for calculating and setting the voltage application mode to the electromagnetic solenoid of the VSV 20 is described.
Only the drive timing calculation unit P04 is different from the first embodiment. Therefore, duplicate description of common members or components will be omitted.

In the device for controlling the suspension system of the present embodiment, similarly to the first embodiment, the ACM is controlled based on whether or not a voltage is applied to the electromagnetic solenoid of the VSV 20.
30 is controlled to operate. The VSV drive timing calculation unit P04 basically sets the VSV on time T0 and the VSV off time T1 by the same processing as the flowchart shown in FIG.

In this embodiment, however, the control duty ratio command value and the control phase command value are calculated when it is determined that the operating condition of the internal combustion engine E is the idling operation (step S20 in the flowchart of FIG. 5). At this time, the control command values calculated based on the control maps M01 to M04 for the fuel injection amount and the engine speed are corrected based on the intake air amount and the ignition timing.

The procedure for calculating the control command value of the VSV 20 according to the present embodiment will be described below with reference to FIGS. The VSV drive timing calculation unit P04 calculates the VSV
When calculating the on / off operation timing of 20, it is determined whether the operating condition of the internal combustion engine E is high-speed operation, medium-low speed operation, or idling operation, similarly to the processing of steps S10 to S13 in the flowchart of FIG. When it is determined that the operation condition is the idling operation, the VSV drive timing calculation unit P04 calculates the control duty ratio command value and the control phase command value based on a series of processes shown in the flowchart of FIG. Hereinafter, this processing will be described.

In calculating these control command values, the current shift position is determined based on the output signal of the shift position sensor S05 (step S251), and the control maps M01 to M04 provided separately for each shift position (step S251). FIG.
The processing up to the calculation of the control duty ratio command value and the control phase command value based on FIG. 8 (steps S252 to S255) is the same as that of the first embodiment.

In this embodiment, each control command value calculated based on the fuel injection amount and the engine speed is corrected according to the intake air amount and the ignition timing, respectively (step S256, step S256). S257). The intake air amount is based on the control maps M05 and M06 for each control command value shown in FIGS. 10A and 10B (step S256), and the ignition timing is shown in FIG.
The correction amounts are calculated based on the control maps M07 and M08 shown in (a) and (b) (step S257). Then, the VSV drive timing calculation unit P04
Performs the correction based on the correction amount thus obtained,
The final control duty ratio command value and control phase command value are calculated.

The control map M0 shown in FIG.
5 stores the correction amount of the control duty ratio command value for the intake air amount, and the control map M06 shown in FIG. 10B stores the correction amount of the control phase command value for the intake air amount. Further, the control map M07 shown in FIG. 11A shows the correction amount of the control duty ratio command value with respect to the ignition timing in the control map M08 shown in FIG.
Stores the correction amount of the control phase command value with respect to the ignition timing.

Thereafter, the VSV 20 is turned on / off based on the VSV on time T0 and the VSV off time T1 (step S18 in the flowchart of FIG. 5) calculated using the control command values thus obtained, and the ACM
Generating a braking vibration in 30 is the same as in the first embodiment.

As described above, in the present embodiment, the ACM3
The control command value of the braking vibration that generates 0 is calculated based on the fuel injection amount and the engine speed, which are control parameters reflecting the output torque of the internal combustion engine E, and further calculated based on the intake air amount and the ignition timing. The control command value is corrected. Such correction is performed for the following reasons.

First, the reason for performing the correction based on the intake air amount will be described. If the intake air amount is different even if the fuel injection amount is the same, that is, if the air-fuel ratio is different, the combustion speed of the air-fuel mixture changes, and the timing of the output torque of the internal combustion engine E also changes accordingly. I do. For example, when the air-fuel ratio is low, the combustion speed of the air-fuel mixture becomes slower than when the air-fuel ratio is high, and the timing of the output torque is also delayed.
If the timing of the output torque of the internal combustion engine E changes in this way, the timing of the occurrence of engine vibration also changes in conjunction with this.

When the air-fuel ratio changes due to the change in the combustion speed, the magnitude of the output torque of the internal combustion engine E and, consequently, the magnitude of the engine vibration also change to some extent.

In response to such a change in the timing and magnitude of the engine vibration caused by the change in the intake air amount, the control command value of the braking vibration generated by the ACM 30 is adjusted by the intake air amount, so that more appropriate braking can be achieved. Vibration can be output, and transmission of engine vibration can be more effectively suppressed.

In this embodiment, as is apparent from the control map M06 shown in FIG. 10B, the control phase command value is increased in accordance with the increase in the intake air amount, that is, VS.
The correction is performed so that the V-on time T0 is delayed.
Therefore, in the present embodiment, the timing of occurrence of the braking vibration is
The adjustment is made to be delayed according to the increase in the intake air amount. Further, as shown in a control map M05 in FIG. 10A, the control vibration ratio command value is reduced in accordance with the increase of the intake air amount, so that the period during which the VSV 20 is turned on is shortened, so to speak, the braking vibration. An adjustment has been made to reduce the size of.

Next, the reason why the correction is performed according to the ignition timing will be described. If the ignition timing is different, the generation timing of the output torque of the internal combustion engine E caused by the explosion of the air-fuel mixture naturally differs, and accordingly, the generation timing of the engine vibration also differs. That is, if the ignition timing is delayed, the timing at which engine vibration occurs is also delayed. Further, the magnitude of the output torque of the internal combustion engine E also changes according to the ignition timing.
Therefore, if the adjustment is performed in accordance with the ignition timing, the braking vibration can be appropriately adjusted in accordance with the generation mode of the engine vibration, and thus the transmission of the engine vibration can be reduced more effectively.

In the present embodiment, as is apparent from the control map M08 shown in FIG. 11B, the control phase command value is increased according to the delay of the ignition timing to delay the generation timing of the braking vibration. Has been adjusted. FIG.
As shown in the control map M07 of FIG. 1 (a), the adjustment is performed such that the control duty ratio command value is reduced according to the delay of the ignition timing to reduce the magnitude of the braking vibration.

In general, in an internal combustion engine, so-called knock control for stabilizing a combustion state by retarding an ignition timing in accordance with occurrence of knocking may be performed. When such knock control is performed, the ignition timing may be changed irrespective of a control parameter indicating an engine operating state other than the ignition timing, such as the fuel injection amount or the engine speed. Even in such a case, if the control command value is adjusted according to the ignition timing as in the present embodiment, the braking vibration can be adjusted sufficiently appropriately according to the change in the ignition timing.
Transmission of engine vibration can be sufficiently reduced.

As described above, according to the present embodiment, the following effects can be obtained in addition to the effects (1) to (5) of the first embodiment. Become like

(6) VS according to intake air amount (air-fuel ratio)
By adjusting the control command value of V20, the braking vibration can be appropriately adjusted according to the generation mode of the engine vibration that changes with the air-fuel ratio, and the transmission of the engine vibration can be more effectively reduced. .

(7) In addition, the VSV 20 according to the ignition timing
Also, by adjusting the control command value, the braking vibration can be appropriately adjusted according to the generation mode of the engine vibration that changes with the same ignition timing, so that the transmission of the engine vibration can be more effectively reduced. Become. It is particularly effective when such adjustment according to the ignition timing is performed together with knock control for changing the ignition timing for stabilizing combustion.

The suspension system of each embodiment described above can be modified as follows. In the second embodiment, each control command value of the VSV 20 is corrected by the intake air amount, but may be corrected by the air-fuel ratio. In such a case, the same effect can be obtained.

In the second embodiment, the control duty ratio command value and the control phase command value are both corrected by the intake air amount and the ignition timing. A configuration in which only one of them is corrected may be adopted.

Also, in the second embodiment, the VS
Although the configuration is such that the control command value of V20 is corrected based on the intake air amount and the ignition timing, it may be configured such that only one of the intake air amount and the ignition timing is corrected. In such a case, in addition to the effects described in the above (1) to (5), any one of the effects (6) and (7) can be obtained.

Further, in each of the above embodiments, the ACM 30 generates the braking vibration according to the engine vibration only when it is determined that the operating condition of the internal combustion engine E is the idling operation. In the case of other operating conditions, transmission of engine vibration by such braking vibration may be reduced.

In each of the above embodiments, the control map M01 provided separately for each shift position.
Each of the control command values is calculated using M04 to M04. However, a control map in which a difference for each shift position is included in advance is created, and the control command value is calculated from the same control map at any shift position. You may do so. Alternatively, each control command value may be calculated from the same control map independently of the shift position, and then corrected according to the shift position. When the suspension system of the present invention is applied to an automobile having a manual transmission, it is not necessary to correspond to each shift position, that is, to switch a control map according to the shift position.

Also, in each of the above embodiments, the VSV 20
, That is, both the output timing and the magnitude of the braking vibration generated by the ACM 30 are controlled, but only one of them may be controlled.

In the above embodiments, the control command value of the VSV 20 is obtained by using the fuel injection amount and the engine speed as parameters, that is, the braking vibration is controlled based on the fuel injection amount and the engine speed. However, the configuration may be such that the braking vibration is controlled based on only the fuel injection amount without using the engine speed. In such a case as well, it is difficult to accurately estimate the generation timing of the output torque, but it is possible to control the braking vibration by estimating the output torque from the fuel injection amount.
Also in such a case, it is possible to control the braking vibration by estimating the generation timing of the output torque from the engine operation state quantity other than the engine speed, for example, the ignition timing and the fuel injection timing.

In each of the above embodiments, the control command value of the VSV 20 is obtained by using the fuel injection amount and the engine speed as parameters. However, the output torque is calculated in advance, and the calculated output torque is used as a parameter. The control command value may be obtained as follows. For example, the magnitude of the output torque of the internal combustion engine E, or the correlation between the magnitude of the output torque and the output timing, and the amount of fuel injection and the engine speed, or the intake air amount and the ignition timing in addition to these, are determined in advance from experiments and theory. Ask for it. Then, a control map corresponding to the magnitude of the output torque estimated based on the correlation or the magnitude and the output timing is created, and a control command value is calculated from the control map. With such a configuration, a configuration for obtaining a control command value using the output torque as a parameter can be embodied. In addition, in the case of such a configuration, the control structure can be further simplified.

In each of the above embodiments, the braking torque is controlled by estimating the output torque of the internal combustion engine E from the fuel injection amount. However, the output torque or the output torque and its generation timing are determined by the combustion characteristics. The braking vibration may be controlled by using another engine operating state quantity that is reflected regardless of the change in the engine operating state.

Further, the output torque itself may be directly measured without using the substitute value of the output torque and used for controlling the braking vibration. In the above embodiments, the ACM 30 outputs the braking vibration based on the supply / discharge of the intake negative pressure. However, the suspension device that generates the braking vibration by another method such as an electromagnetic actuator may be used. The control structure according to each of the above embodiments can be applied.

In each of the above embodiments, the case where the suspension system of the present invention is applied to an in-line four-cylinder automobile gasoline engine has been described. The present invention can be applied to other types of internal combustion engines, such as a diesel engine and an internal combustion engine other than those mounted on a vehicle, as long as the internal combustion engine changes in combustion characteristics, in the same manner as in the above embodiments. When the present invention is applied to a diesel engine, by performing a correction based on the fuel injection timing based on the correction based on the ignition timing in the second embodiment, an effect based on this can be obtained.

In each of the above embodiments, the case where the suspension according to the present invention is applied to an internal combustion engine that operates by switching between combustion at the stoichiometric air-fuel ratio and combustion at the lean air-fuel ratio has been described. Then, it was described that transmission of engine vibration to the support body (vehicle body) can be effectively suppressed irrespective of a change in combustion characteristics due to switching of the air-fuel ratio. The suspension according to the present invention can also be applied to an internal combustion engine whose combustion characteristics change during operation of the engine in response to an operation other than the switching of the air-fuel ratio, and in this case as well, the engine vibration is applied to the support. Transmission can be effectively reduced. As an example of an internal combustion engine in which such combustion characteristics change, an internal combustion engine in which a compression ratio, an expansion ratio, a fuel pressure, a valve timing, a valve lift, and the like are changed in addition to the change in the air-fuel ratio is considered. In such a case, besides the fuel injection amount,
For example, the control vibration generation mode is controlled using an operating state such as a valve timing as a parameter reflecting the output torque.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a schematic structure of an internal combustion engine to which the first embodiment of the suspension system for an internal combustion engine of the present invention is applied.

FIG. 2 is an exemplary sectional view showing the internal structure of the suspension device according to the embodiment;

FIG. 3 is a functional block diagram showing a schematic configuration of a device that controls the suspension device of the embodiment.

FIG. 4 is a time chart showing a VSV drive control mode.

FIG. 5 is a flowchart illustrating a control procedure of a VSV drive timing calculation unit.

FIG. 6 is a flowchart showing a control procedure of a VSV drive timing calculation unit.

FIG. 7 is a graph showing a relationship between a VSV control duty ratio and a fuel injection amount and an engine speed, which are map data.

FIG. 8 is a graph showing a relationship between a VSV control phase and a fuel injection amount and an engine speed, which are map data.

FIG. 9 is a flowchart showing a control procedure of a VSV drive timing calculation section of a second embodiment of the suspension system for an internal combustion engine of the present invention.

FIG. 10 is a graph showing a relationship between intake air amount, which is map data, and correction amounts of a control phase and a control duty ratio.

FIG. 11 is a graph showing a relationship between ignition timing, which is map data, and a correction amount of a control phase and a control duty ratio.

[Explanation of symbols]

Reference Signs List 10: intake passage, 11: throttle valve, 12: throttle drive device, 15: injector, 16: igniter, 17: accelerator pedal, 18: crankshaft,
19 ... rotor, 20 ... negative pressure switching valve (VSV), 21
... Negative pressure passage, 22 ... Atmospheric pressure passage, 23 ... Supply / discharge passage, 24
... Electronic control device, 30 ... Active control mount (ACM), 31 ... Connector, 32 ... Main body case, 33
... cushioning member, 34 ... isolation member, 35 ... diaphragm, 3
6 Fixture, 37 Air chamber, 39 Elastic member, 40, 4
Reference Signs List 1: liquid chamber, S01: air flow meter, S02: crank angle sensor, S03: throttle opening sensor, S04: vehicle speed sensor, S05: shift position sensor, S06: accelerator opening sensor, S00: other sensors, P01: rotation Numerical calculation unit, P02: fuel injection amount calculation unit, P03: ignition timing calculation unit, P04: VSV drive timing calculation unit, P05: V
SV drive circuit, B: vehicle body, E: internal combustion engine.

Claims (8)

[Claims] 1. A suspension device for an internal combustion engine, wherein the internal combustion engine, whose combustion characteristics change during operation, is suspended and supported on a support. A suspension device for an internal combustion engine, comprising: a vibration reduction mechanism that reduces transmission to the engine; and control means that controls the braking vibration generation mode of the vibration reduction mechanism based on an output torque of the engine. 2. A suspension system for an internal combustion engine, wherein the internal combustion engine, whose combustion characteristics change during operation, is supported on a support, the braking system generating a vibration against the vibration of the internal combustion engine to generate a vibration of the engine. A vibration reduction mechanism for reducing transmission to the engine, and control means for controlling the braking vibration generation mode of the vibration reduction mechanism based on an operation state amount reflecting an output torque of the engine. Suspension device. 3. The suspension system for an internal combustion engine according to claim 2, wherein the operation state quantity referred to by the control means is a fuel injection amount of the engine. 4. A suspension system for an internal combustion engine according to claim 2, wherein said operation state amount referred to by said control means is a fuel injection amount and an engine speed of said engine. Suspension device. 5. The suspension system for an internal combustion engine according to claim 3, wherein the operation state quantity of the engine referred to by the drive control means is:
A suspension system for an internal combustion engine, further comprising an ignition timing of the engine. 6. The suspension system for an internal combustion engine according to claim 3, wherein the operating state quantity of the engine referred to by the drive control means is:
A suspension system for an internal combustion engine, further comprising an intake air amount of the engine. 7. A suspension system for an internal combustion engine according to claim 1, wherein said control means controls a phase of a braking vibration generated from said vibration reducing mechanism. A suspension device for an internal combustion engine. 8. A suspension system for an internal combustion engine according to claim 1, wherein said drive control means controls the magnitude of braking vibration generated by said vibration reduction mechanism. A suspension device for an internal combustion engine, comprising: