JPH0633982A - Vibration reduction device of vehicle - Google Patents

Abstract

PURPOSE:To perform an optimum vibration reducing operation according to the rolling state of an engine in reducing vehicle vibration by vibrating of a vehicle in the opposite phase to and at the same amplitude as the vehicle vibration. CONSTITUTION:A distortion gauge 29 disposed on an engine mount is used to recognize the direction and amount of rolling of an engine due to the acceleration and deceleration of a vehicle and the transfer function of a digital filter 20 is varied with changes in the transfer characteristics of the vehicle as the result of changes in the direction and amount of rolling of the engine, so as to perform optimum vibrating control.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration reducing device for a vehicle, and more particularly, it is equipped with an actuator for exciting the vehicle.
The present invention relates to an improvement of a vehicle which is excited in the same amplitude as a phase opposite to the vehicle vibration to reduce the vehicle vibration.

[0002]

2. Description of the Related Art Conventionally, as a vibration reducing device for a vehicle of this type, an engine mount supporting an engine has a function as a vibration exciter, as disclosed in, for example, Japanese Patent Laid-Open No. 3-219139. Then, the engine mount generates an excitation signal such that a vibration having a phase opposite to the phase of the vehicle body vibration and the same amplitude is applied to the vehicle body, and the vehicle body vibration is detected by the vibration sensor to detect the detected vibration. There is known a vibration reducing device by a so-called optimization method in which vehicle body vibration is reduced by performing feedback control of the excitation signal so that the signal becomes smaller.

[0003]

By the way, in the vibration reducing device employing the engine mount as the vibration exciter as described above, when the vehicle is accelerated or decelerated,
When a so-called roll that tilts with the axis of the crankshaft as the swing center is generated, the load applied to the vibration exciter changes depending on the roll direction and the roll amount. Therefore, even if the same vibration signal is given to the vibration exciter, the vibration force of the vibration exciter will differ depending on the roll state of the engine.
There is a possibility that a situation may occur in which the vibration exciter cannot perform the optimum vibration reduction operation for the vibration.

Therefore, the inventors of the present invention pay attention to the load acting on the vibration exciter when a roll occurs in the engine,
It was considered to change the control state of the vibration exciter by detecting the roll direction and the roll amount of the engine.

The present invention has been made in view of the above problems, and an object thereof is to obtain a structure capable of performing an optimum vibration reducing operation according to the roll state of the engine.

[0006]

To achieve the above object, the present invention relates to a digital filter for generating a drive signal for controlling the drive of an actuator according to the roll state of the engine accompanying the acceleration and deceleration of the vehicle. The transfer function was changed. Specifically, the invention according to claim 1 is as shown in FIG.
As shown in FIG. 3, an actuator 3 provided between the vehicle body and the engine for generating a vibration force, a vibration sensor 7 for detecting the vibration of the vehicle, a reference signal based on the vibration emitted from the engine 2, and receiving the reference signal. And a control means 24 for generating a drive signal for exciting the vehicle at a phase opposite to that of the vehicle vibration and having the same amplitude based on the signal, and the control means 24 responds to the vibration transfer characteristic of the vehicle. A digital filter 20 having a transfer function is provided, and the transfer function of the digital filter 20 and the vibration sensor 7 are provided.
A vibration reduction device for a vehicle configured to reduce the vibration of the vehicle by generating a vibrating force by the actuator 3 by transmitting a drive signal, which is feedback-corrected based on the vibration signal of the above, to the actuator 3. It is assumed. Then, the transfer function of the digital filter 20 is
The transfer function changing means 30 for changing the roll direction and the roll amount of the engine 2 is provided.

According to a second aspect of the present invention, in the vehicle vibration reducing apparatus according to the first aspect, the roll direction and the roll amount of the engine are recognized based on the acceleration / deceleration state of the vehicle, and the transfer function changing means determines the roll direction and the roll amount. The transfer function of the digital filter is changed based on the acceleration / deceleration state of the vehicle.

[0008]

With the above-described structure, the following effects can be obtained in the present invention. According to the first aspect of the invention, the control means 2 controls the reference signal based on the vibration generated from the engine 2 and the vibration signal of the vibration sensor 7 for detecting the vibration of the vehicle.
4, the control means 24 creates a drive signal based on the reference signal so as to excite the vehicle in the opposite phase and the same amplitude as the vehicle vibration. In addition, the digital filter 2
The drive signal feedback-corrected based on the transfer function of 0 and the vibration signal of the vibration sensor 7 is transmitted to the actuator 3, whereby the actuator 3 generates an exciting force to reduce the vibration of the vehicle. At this time, the transfer function changing means 30 changes the transfer function of the digital filter 20 based on the roll direction of the engine 2 and the roll amount thereof. Therefore, the actuator 3 performs the optimum vibration reduction operation according to the roll state of the engine 2, and the vibration of the vehicle can be efficiently reduced.

According to the second aspect of the present invention, the roll direction and the roll amount of the engine are recognized by the acceleration / deceleration state of the vehicle, and the transfer function changing means changes the transfer function of the digital filter based on the acceleration / deceleration state of the vehicle. . This allows
Control reliability is improved.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.

In FIG. 2, reference numeral 1 is a vehicle body, 2 is an engine arranged in an engine room 1b below a hood 1a of the vehicle body 1, and the engine 2 has a mount 3 and a support bracket 4 for elastically supporting the lower portion thereof. Through the car body 1
The engine 2 and the vehicle body 1 and the like elastically support the entire vehicle.

As shown in FIG. 3, the mount 3 has a function as an actuator for vibrating the engine 2 as a vibration source. That is, the mount 3 shown in the figure includes a casing 3b in which an insertion rod 3a to which a lower end portion of the engine 2 is fixed is arranged at an upper end portion, and a hollow cone-shaped support rubber having an outer peripheral end fixed to a lower end portion of the casing 3b. 3c and a supporting portion 3d to which the inner peripheral end of the supporting rubber 3c is fixed. The inserting rod 3e provided at the lower end of the supporting portion 3d is fixed to the vehicle body 1.

A main liquid chamber 3f is formed in the casing 3b, and a sub liquid chamber 3h partitioned by a diaphragm 3g is formed below the support rubber 3c. Between the main liquid chamber 3f and the sub liquid chamber 3h, a small-diameter orifice 3i formed on the side of the support rubber 3c is formed, and the fluid between the main liquid chamber 3f and the sub liquid chamber 3h is made into the orifice 3i. It is a configuration in which they are distributed through each other. Furthermore, the casing 3b
A vibrating plate 3j forming the upper surface of the main liquid chamber 3f is slidably arranged on the inner peripheral surface of the casing 3b via a rubber 3k, and above the vibrating plate 3j. A permanent magnet 3m and an electromagnetic coil 3n for sliding the vibrating plate 3j up and down are arranged, and the vibrating plate 3j is vibrated vertically by the permanent magnet 3m and the electromagnetic coil 3n to increase the volume of the main liquid chamber 3f. By making it variable, the main liquid chamber 3f and the sub liquid chamber 3h
The fluid is repeatedly circulated through the orifice 3i to vibrate the support rubber 3c up and down, and as a result, a vibrating force is generated.

Further, in FIG. 2, reference numeral 7 denotes an acceleration sensor as a vibration sensor which is arranged near the left front wheel of the vehicle 1 and detects the vibration of the vehicle by the vertical acceleration of the vehicle body 1. The detection signal is input to the controller 8, and the controller 8 controls the vibration of the engine mount 3 based on the vertical acceleration signal detected by the acceleration sensor 7 to vertically vibrate the engine 2.
This is a configuration for reducing vibration of the vehicle body.

Next, FIG. 4 shows a block configuration of the vehicle vibration reduction control by the controller 8. In the figure, 10 is an engine rotation cycle measuring circuit for measuring the cycle of engine rotation based on the ignition signal of the air-fuel mixture in the engine 2, and 11 is based on the cycle of engine rotation measured by the cycle measuring circuit 10. It is a reference signal generator that generates a reference signal R related to the vibration of the engine 2. Further, 12 is an amplifier for amplifying an acceleration signal as a vibration signal from the acceleration sensor 7 by a set gain G2,
13 is a low-pass filter that filters low-frequency components of the acceleration signal amplified by the amplifier 12, 14 is an A / D converter that converts the acceleration signal filtered by the low-pass filter 13 from an analog value to a digital value, and 15 is A vibration signal generator that inputs an acceleration signal S from the A / D converter 14 and generates a vibration signal A as a drive signal for controlling vibration of the engine mount 3 based on the acceleration signal S. . Further, 17 is a D / A converter for converting the vibration signal A generated by the vibration signal generator 15 from a digital value to an analog value, and 18 is a vibration signal from the D / A converter 17. A low-pass filter for filtering low-frequency components, 19 is an amplifier for amplifying the excitation signal filtered by the low-pass filter 18 by a set gain G1, and the excitation signal amplified by the amplifier 19 is sent to the engine mount 3. Is output.

The excitation signal generator 15 uses the least squares method (Least method) as an algorithm for generating the excitation signal.
Mean Square Method (= LM
The adaptive algorithm of S)) is used. FIG. 5 shows the internal configuration of the excitation signal generator 15 using the adaptive algorithm of the least square method. In the figure, reference numeral 20 indicates that after the vibration signal A is output from the vibration signal generator 15, the mount 3 is vibration-controlled by the vibration signal A, and as a result, the vehicle vibration is changed. Change of acceleration sensor 7
A digital filter that models the transfer function H from when the acceleration signal S is input to the excitation signal generator 15 and when 21 is used to rewrite the filter coefficient according to the acceleration signal S from the acceleration sensor 7. A convergence coefficient calculation circuit for calculating the convergence coefficient α of the reference signal R
A multiplier for multiplying the transfer function H and the convergence coefficient α by 23, the filter coefficient is sequentially updated for each output of the multiplier 22, based on the output value thereof, and the reference signal is based on the updated filter coefficient. This is an adaptive filter that outputs an excitation signal A having the same amplitude in opposite phase. Therefore, the excitation signal generator 1
5, receives the acceleration signal S from the acceleration sensor 7,
An adaptive filter 23 based on the acceleration signal S and the convergence coefficient
The filter coefficient is updated to appropriately adjust the vibration signal A, the engine mount 3 is driven and controlled by the vibration signal A, and the phase and the amplitude of the vibration applied to the vehicle are set in the opposite phase to the vibration of the engine 2. The control means 24 is configured to reduce the vibration of the vehicle with the same amplitude.

As a characteristic feature of this embodiment, the excitation signal generator 15 includes the digital filter 20.
A transfer characteristic adjusting mechanism 26 for changing the transfer function of Further, the transfer characteristic adjusting mechanism 26 includes
A signal from the engine roll amount determination circuit 27 is input, and the transfer characteristic adjusting mechanism 26 changes the transfer function of the digital filter 20 based on this signal. Further, the engine roll amount determination circuit 27
A signal from a strain gauge 29 arranged on the support rubber 3c of the mount 3 is input to the
The roll direction and roll amount of the engine 2 are detected by the signal from the strain gauge 29. As a result, the transfer characteristic adjusting mechanism 26, the engine roll amount determination circuit 27, and the strain gauge 29 constitute the transfer function changing means 30 in the present invention.

Therefore, the digital filter 2 in this example
As the transfer function changing operation of 0, the roll direction and the roll amount of the engine 2 are detected by the signal of the strain gauge 29 input to the engine roll amount determination circuit 27, and based on this, the memory map shown in FIG. 6 is used. Calculate the coefficient vector when setting the transfer function. Explaining this memory map, the coefficient vector is changed according to the roll amount. For example, when the roll amount is maximum, the coefficient vector is set to hRL, and when the roll amount is minimum, the coefficient vector is set to hRS. Then, the transfer function of the digital filter 20 is calculated based on the set coefficient vector. That is, the transfer function is set according to the transfer characteristic of the vehicle that changes depending on the roll direction and the roll amount of the engine 2 accompanying the acceleration / deceleration state of the vehicle.

As described above, according to the configuration of this example, the transfer function of the digital filter 20 is changed in accordance with the change in the load of the engine mount 3 due to the change in the roll direction and the roll amount of the engine 2, and the excitation signal is generated. Therefore, the engine mount 3 can be caused to perform an optimum reducing operation according to the engine roll state, and the vibration of the vehicle body can be efficiently reduced, resulting in the quietness of the vehicle. The property is improved.

(Second Embodiment) Next, a second embodiment according to the present invention will be described. In the above-described first embodiment, the strain gauge 29 detects the roll state of the engine 2, but in this example, the roll state of the engine 2 is recognized by detecting the acceleration / deceleration state. Is. The configuration of this example will be described below.

As shown in FIG. 7, the transfer characteristic adjusting mechanism 26
A signal from the acceleration / deceleration state detection means 28 is input to the. Various signals such as vehicle speed, throttle opening, throttle change rate, brake switch, longitudinal acceleration, etc. are input to the acceleration / deceleration state detecting means 28, and the acceleration / deceleration state and acceleration / deceleration of the vehicle are controlled by these signals. The speed is detected to recognize the roll direction and the roll amount of the engine 2. Then, the transfer characteristic adjusting mechanism 26 changes the transfer function of the digital filter 20 based on the signal from the acceleration / deceleration state detection circuit 28 based on the recognized roll direction and roll amount of the engine 2. Thus, in this example, the transfer characteristic adjusting mechanism 2
6. The transfer function changing means 30 according to the present invention is constituted by the acceleration / deceleration state detection circuit 28.

As described above, according to the configuration of this embodiment as well, the transfer function of the digital filter 20 is changed according to the transfer characteristic of the vehicle which changes according to the change in the roll direction and the roll amount of the engine 2 to correct the excitation signal. By doing so, depending on the engine roll state, the engine mount 3
The optimum reduction operation can be performed, and the vibration of the vehicle body can be efficiently reduced. Further, in the case of this example, it is not necessary to dispose a strain gauge on the engine mount 3, and the acceleration / deceleration state can be surely recognized, so that the reliability of control can be improved.

The configurations of the first and second embodiments described above may coexist to further improve the reliability of recognition of the engine roll state. Further, as the installation position of the acceleration sensor 7, a floor panel, a door inner panel,
It is desirable to dispose it on various vibration generating parts such as a steering wheel and a shift knob.

[0024]

As described above, according to the present invention, the following effects are exhibited. According to the first aspect of the invention, since the transfer function changing means for changing the transfer function of the digital filter based on the roll direction and the roll amount of the engine is provided, the actuator is set to the roll state of the engine. According to the load acting on the actuator, it is possible to efficiently reduce the vibration of the vehicle.

According to the second aspect of the present invention, the roll direction and the roll amount of the engine are recognized by the acceleration / deceleration state of the vehicle, and the transfer function changing means is configured to detect the digital filter based on the acceleration / deceleration state of the vehicle. Since the configuration is such that the transfer function is changed, the reliability of control can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of the present invention.

FIG. 2 is a diagram showing an overall schematic configuration of a vehicle.

FIG. 3 is a diagram showing a specific configuration of an engine mount that also serves as an actuator for vibration control.

FIG. 4 is a diagram showing a block configuration of vibration control.

FIG. 5 is a diagram showing a configuration of an excitation signal generator using an LMS adaptive algorithm in the first embodiment.

FIG. 6 is a diagram showing a memory map for setting a coefficient vector according to an engine roll amount.

FIG. 7 is a view corresponding to FIG. 5 in the second embodiment.

[Description of Reference Signs] 1 vehicle body (vibration element) 2 engine 3 engine mount (actuator) 7 acceleration sensor (vibration sensor) 20 digital filter 24 control means 30 transfer function changing means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Norihiko Nakao 3-1, Shinchi Fuchu-cho, Aki-gun, Hiroshima Mazda Co., Ltd. In-company (72) Yutaka Tsukahara, 3-1, Shinchi Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) In-house Shingo Harada, 3-1-1 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Corporation

Claims (2)

[Claims] 1. An actuator provided between a vehicle body and an engine for generating an exciting force, a vibration sensor for detecting a vibration of a vehicle, a reference signal based on the vibration emitted from the engine, and a reference signal based on the reference signal. And a control means for generating a drive signal for exciting the vehicle in a phase opposite to the vehicle vibration and having the same amplitude, and the control means includes a digital signal having a transfer function corresponding to the vibration transfer characteristic of the vehicle. A filter is provided, and a drive signal feedback-corrected based on the transfer function of the digital filter and the vibration signal of the vibration sensor is transmitted to the actuator, so that the actuator generates an exciting force and In a vehicle vibration reducing device configured to reduce vibration, a transfer function of the digital filter is set to a low engine speed. Vibration reduction apparatus of a vehicle, wherein the direction and the transfer function changing means for changing, based on the roll amount is provided. 2. The roll direction and roll amount of the engine are recognized by the acceleration / deceleration state of the vehicle,
The vehicle vibration reduction device according to claim 1, wherein the transfer function changing means is configured to change the transfer function of the digital filter based on the acceleration / deceleration state of the vehicle.