JPH08177961A - Vibration proof supporting device - Google Patents

Abstract

PURPOSE: To correctly supply drive current desirable for an electromagnetic actuator without causing remarkable increase of cost, enlarged size of the device, or the like. CONSTITUTION: In an engine mount 1 in which vibration transmitted from an engine 30 to a member 35 is reduced by active supporting force generated by displacing up and down a magnetic path member 12 by means of an electromagnetic actuator 10, when the absolute value of the alternating current component of a control signal (y) supplied from a controller 20 to the drive circuit 19 of the exciting coil 10B of the electromagnetic actuator 10, the alternating current component of the control signal (y) is corrected in the direction of making the change steep. The correcting quantity is set according to the amplitude and the frequency of the alternating current component before correction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for supporting a vibrating body such as an engine of a vehicle on a support body such as a vehicle body while vibration-proofing the vibrating body. A type that forms a fluid chamber and changes the volume of the fluid chamber by displacing a movable member that forms a part of a partition wall in the fluid chamber by the magnetic force of an electromagnetic actuator, thereby generating an active supporting force. In the vibration-proof support device, it is possible to accurately supply a desired drive current to the electromagnetic actuator without causing a large increase in cost or an increase in size of the device.

[0002]

2. Description of the Related Art As a conventional antivibration support device of this type,
For example, the one disclosed in Japanese Patent Laid-Open No. 3-24338 is known. That is, the anti-vibration support device described in the above publication has a vibrating body and a supporting elastic body interposed between the supporting bodies, and a fluid chamber defined by the supporting elastic body, and the fluid chamber contains a fluid. On the other hand, the volume of the fluid chamber is supported by an elastic body so that the volume of the fluid chamber can be varied, and the volume of the fluid chamber is displaced by appropriately displacing the movable plate by an electromagnetic actuator consisting of a permanent magnet and an electromagnet. Fluctuates
The support elastic body is elastically deformed in the expansion direction to generate a control force capable of canceling the vibration transmitted to the vibration-proof support device. In other words, the movable plate is pulled to the electromagnetic actuator side to a predetermined neutral position where the supporting force of the elastic body that elastically supports itself and the magnetic force of the permanent magnet are balanced, but if the magnetic force generated by the electromagnet is adjusted appropriately, Since the magnetic force applied to the magnet increases or decreases, the gap between the movable plate and the electromagnetic actuator can be changed to an arbitrary value within a possible range, and the volume of the fluid chamber can be changed.

[0003]

Here, as a circuit for driving the electromagnetic actuator in the conventional anti-vibration supporting device as described above, for example, a PWM (Pulse Width Modu) is used.
Various types of circuits are conceivable, including pulse width modulation), but in any case, the electromagnetic actuator is driven to cancel a vibration of a relatively large amplitude, such as a vibration generated when a vehicle is idling. When the current becomes a large current, even if the control signal for the drive circuit has a waveform as shown in FIG. 9A, the drive current flowing through the electromagnetic actuator is the absolute value of the current value as shown by the solid line in FIG. 9B. There is a delay when the value returns to 0. The reason is that the time constant (L / R) increases when the inductance of the exciting coil of the electromagnetic actuator is large to some extent, but the speed in the direction in which the current is discharged (damped) does not become higher than the time constant. That is, the current does not follow in the attenuation direction when the frequency exceeds a certain level by simply reducing the voltage.

If the actual drive current becomes as shown in FIG. 9B, a large step-like input is applied when the direction of the current changes (when the magnitude of the current value becomes 0). Therefore, a step-like force corresponding to the step-like input is applied to the movable plate to excite the movable plate resonance, and a high-frequency vibration as shown in FIG. 9C is generated. Will occur.

Such a vibration of the movable plate causes an abnormal noise, and the frequency of the abnormal noise is much higher than the frequency of the vibration of the vibration source (for example, engine vibration). There is a possibility that the passengers in the room may feel uncomfortable. In addition, the superposition of high-frequency vibrations on the movable plate means that the high-frequency vibrations are transmitted to the side of the support body such as the vehicle body, which leads to deterioration of the image stabilization control performance.

In order to solve such a problem, for example, the driving current supplied to the electromagnetic actuator is monitored in real time, and the current value is applied to the exciting coil of the electromagnetic actuator so as to accurately follow the control signal. It may be possible to perform feedback control of the generated voltage with an analog circuit. However, in this case, due to the circuit configuration, the A / D
Various components such as a converter, a monitor resistor, a comparator, and a low-pass filter are newly required, which causes a significant increase in cost and an increase in size of the device.

The present invention has been made by paying attention to the unsolved problem of such a conventional anti-vibration supporting device, and a desired driving current for an electromagnetic actuator can be obtained without causing a significant increase in cost. It is an object of the present invention to provide an anti-vibration support device that can be accurately supplied and can prevent the generation of abnormal noise.

[0008]

In order to achieve the above object, the invention according to claim 1 provides a supporting elastic body interposed between a vibrating body and a supporting body, and a fluid chamber defined by the supporting elastic body. A fluid enclosed in the fluid chamber, a magnetizable movable member elastically supported so as to form part of a partition wall of the fluid chamber, and the movable member in a direction in which the volume of the fluid chamber changes. An electromagnetic actuator that generates a magnetic force to be displaced, a drive circuit that supplies a drive current according to a control signal to an exciting coil of the electromagnetic actuator, and a control that generates and outputs the control signal so as to reduce vibration on the support side. Means, and a control signal correction means for correcting the AC component of the control signal in a direction in which the change becomes steep when the absolute value of the AC component of the control signal decreases.

According to a second aspect of the present invention, in the vibration isolating support device according to the first aspect of the invention, the control signal correction means is responsive to the amplitude and frequency of the AC component of the control signal before correction. To set the correction amount. According to a third aspect of the present invention, in the image stabilizing support device according to the first or second aspect, the drive circuit is a pulse width modulation type drive circuit, and the control signal is a variable duty ratio control. It is a pulse signal, and the control signal correction means corrects the duty ratio of the control pulse signal.

Further, according to a fourth aspect of the present invention, in the vibration-damping support device according to the first to third aspects of the present invention, a variable volume sub-fluid chamber communicating with the fluid chamber via an orifice is provided, and A fluid was enclosed in the fluid chamber, the orifice, and the sub-fluid chamber.

[0011]

In the invention according to claim 1, since the fluid chamber is defined by the support elastic body and the fluid is enclosed in the fluid chamber, the support elastic body is provided between the vibrating body and the support body. This is equivalent to the two spring elements, the support spring and the expansion spring that is elastically deformed in the expansion direction of the support elastic body due to the expansion and contraction of the fluid chamber, being interposed in parallel.

On the other hand, when the movable member is displaced by the magnetic force generated by the electromagnetic actuator, the volume of the fluid chamber changes, so that the expansion spring is elastically deformed, and the expansion spring has a spring constant multiplied by a deformation amount. The power of Saa occurs. Therefore, by appropriately controlling the magnetic force generated by the electromagnetic actuator, an active force can be applied between the vibrating body and the supporting body, and the force interferes with the vibration input inputted from the vibrating body side. Therefore, if the control means appropriately generates the control signal and the control signal is supplied to the drive circuit,
The vibration transmitted from the vibrating body side to the support body side is canceled by the force, and the vibration level on the support body side is reduced.

If the absolute value of the AC component of the control signal generated and output by the control means (or the control signal itself if the control signal does not include the DC component) decreases, the control signal is corrected. The means corrects the AC component of the control signal in a direction in which the change becomes steep. That is, when the drive current is delayed with respect to the control signal, the control signal is corrected in such a direction that the delay amount becomes smaller, and as a result, the delay of the drive current is eliminated or reduced.

Here, the delay amount of the drive current with respect to the control signal increases as the amplitude of the AC component of the control signal increases, because the time constant is substantially determined if the hardware configuration of the electromagnetic actuator or the like is determined. It becomes larger as the frequency of the AC component of becomes higher. Since the AC component of the control vibration is determined according to the vibration generated by the vibrating body, the amplitude of the AC component of the control signal is synonymous with the amplitude of the vibration generated by the vibrating body, and the frequency of the AC component of the control signal is the vibration. It is synonymous with the frequency of vibration generated in the body.

Therefore, if the correction amount by the control signal correction means is set as in the second aspect of the invention, the correction amount according to the delay state is set. According to the invention of claim 3, the PWM drive circuit supplies a drive current according to the duty ratio of the control pulse signal as the control signal to the exciting coil of the electromagnetic actuator.
Therefore, if the control signal correction means corrects the duty ratio of the control pulse signal, the effect of the invention according to claim 1 or 2 can be obtained.

Further, in the invention according to claim 4,
Since the fluid chamber and the variable-volume sub-fluid chamber are communicated with each other through the orifice, vibrations of a frequency that allows fluid to flow between the fluid chamber and the sub-fluid chamber are input through the orifice. In some situations, it acts as a conventional fluid-filled anti-vibration support that produces a passive bearing force. In such a situation, it is not necessary to positively displace the movable member.

When a high frequency vibration is input to such a degree that the fluid in the orifice is in a stick state (state in which it cannot move), the electromagnetic actuator displaces the movable member to generate an active supporting force. Then, the same effects as those of the inventions according to claims 1 to 3 are exhibited.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are diagrams showing the configuration of an embodiment of the present invention. This embodiment is a so-called anti-vibration support device according to the present invention in which vibration transmitted from an engine to a vehicle body is actively reduced. It is applied to the active engine mount.

First, the structure will be described. As shown in FIG. 1, the engine mount 1 is integrally provided with a mounting bolt 2a for mounting on an engine 30 as a vibrating body and has a hollow inside and a lower part. The mounting member 2 has an opening, and the upper end of the inner cylinder 3 is caulked to the outer surface of the lower portion of the mounting member 2. Inside the inner cylinder 3, the diaphragm 4 is sandwiched below the caulking prevention portions of the mounting member 2 and the inner cylinder 3 so as to divide the space inside the mounting member 2 and the inner cylinder 3 into upper and lower parts. Of the space that is provided and is divided by the diaphragm 4, the space above the diaphragm 4 communicates with atmospheric pressure, and the orifice structure 5 is provided in the space below the diaphragm 4.

On the other hand, on the outer peripheral surface of the inner cylinder 3, the inner peripheral surface of a cylindrical support elastic body 6 which is formed such that the axial positions of the inner peripheral surface and the outer peripheral surface are higher on the inner peripheral side is vulcanized. The outer peripheral surface of the supporting elastic body 6 is vulcanized and adhered to the inner peripheral surface of the outer cylinder 7. The lower end of the outer cylinder 7 is caulked to an upper flange 8A of a cylindrical actuator case 8 having an open upper surface, and from the lower end of the actuator holding member 8, a member 3 as a support body is formed.
Mounting bolts 9 for mounting on the 5 side project. The head portion 9a of the mounting bolt 9 is housed in the hollow portion of the cap 8b fitted in the recess 8a on the inner bottom surface of the actuator case 8.

Further, inside the actuator case 8, a cylindrical yoke 10A is fixed coaxially to the upper surface of the cap 8b, and an exciting coil is wound around the upper end surface of the yoke 10A with its axis oriented vertically. An electromagnetic actuator 10 including a coil 10B and a permanent magnet 10C fixed with its poles facing up and down is provided on the upper surface of a portion of the yoke 10A surrounded by the exciting coil 10B.
The electromagnetic actuator 1 is provided between the inner peripheral surface of the actuator case 8 and the outer peripheral surface of the electromagnetic actuator 10.
An adapter 10a for fixing 0 is interposed.

A circular metal leaf spring 11 is provided so as to cover the opening side of the actuator case 8. The leaf spring 11 is arranged such that the peripheral edge portion 11a is integrally sandwiched with the flange portion 8A at the caulking prevention portion of the lower end portion of the outer cylinder 7. And the leaf spring 1
1 on the back surface side of the central portion 11b (electromagnetic actuator 10
A disk-shaped magnetic path member 12 made of a material (for example, made of iron) that can be magnetized by a rivet or the like is fixed to the side) so as to open a predetermined clearance with the upper end surface of the electromagnetic actuator 10. The central portion 11b of these leaf springs and the magnetic path member 12 constitute the movable member of the present invention.

Further, in this embodiment, the fluid chamber 15 is formed in a portion defined by the lower surface of the support elastic body 6 and the upper surface of the leaf spring 11, and in the portion defined by the diaphragm 4 and the orifice structure 5. The sub-fluid chamber 16 is formed, and the fluid chamber 15 and the sub-fluid chamber 16 communicate with each other via the orifice 5 a formed in the orifice structure 5. A fluid such as oil is enclosed in the fluid chamber 15, the sub-fluid chamber 16 and the orifice 5a.

The characteristics of the fluid mount determined by the shape of the flow path of the orifice 5a and the like are that when the engine shake occurs during traveling, that is, at 5 to 15 Hz, the engine mount 1
Is adjusted so that it exhibits a high dynamic spring constant and high damping force when it is vibrated. The exciting coil 10B of the electromagnetic actuator 10 is connected to the drive circuit 19 via a harness not shown, and the drive circuit 19 is also connected to the controller 20 as a control means via a harness not shown. , Its drive circuit 19
A drive current I having a direction and magnitude corresponding to the control signal y supplied from the controller 20 is supplied to the exciting coil 10B.

The controller 20 includes a microcomputer, necessary interface circuits, A / D converter, D / A
A vibration is included in the frequency band in which the fluid is immovable between the fluid chamber 15 and the sub-fluid chamber 16 through the orifice 5a, that is, an idle vibration that is a vibration of a higher frequency than the engine shake described above. When muffled sound vibration / vibration at the time of acceleration is input, control vibration having the same cycle as that vibration is generated in the engine mount 1 so that the transmission force of the vibration to the member 35 becomes “0” ( More specifically, the vibration force input to the engine mount 1 due to the vibration on the engine 30 side is the electromagnetic actuator 1
A control signal y is generated and supplied to the drive circuit 19 so as to be canceled by the control force obtained by the electromagnetic force of 0).

Here, idle vibration and muffled sound vibration are
For example, in the case of a reciprocating 4-cylinder engine, the engine rotation 2
The main cause is that the engine vibration of the next component is transmitted to the member 35 via the engine mount 1. Therefore, if the control signal y is generated and output in synchronization with the secondary component of the engine rotation, the vibration transmissibility is increased. Can be reduced. Therefore, in the present embodiment, an impulse signal is generated in synchronization with the rotation of the crankshaft of the engine 30 (for example, in the case of a reciprocating four-cylinder engine, one impulse signal is generated every 180 ° rotation of the crankshaft) and is used as the reference signal x. Output pulse signal generator 2
1 is provided, and the reference signal x thereof is used as a signal representing the generation state of the vibration in the engine 30 by the controller 20.
It is supplied to.

On the other hand, the member 35 is fixed with an acceleration sensor 22 which is close to the mounting position of the engine mount 1 and which detects the vibration state of the member 35 in the form of acceleration and outputs it as a residual vibration signal e. Residual vibration signal e
Is supplied to the controller 20 as a signal representing the vibration after the interference. Then, the controller 20 uses one of the adaptive algorithms based on the reference signal x and the residual vibration signal e, which is one of the successive update type.
It generates and outputs the control signal y in accordance with the Altered-X LMS algorithm, more specifically, the synchronous Filtered-X LMS algorithm.

That is, the controller 20 has an adaptive digital filter W having a variable filter coefficient W _i (i = 0, 1, 2, ..., I-1: I is the number of taps), and the latest reference signal x Is output from the engine 30 via the engine mount 1 at a predetermined sampling clock interval and the filter coefficient W _i of the adaptive digital filter W is sequentially output as the control signal y.
A process of appropriately updating the filter coefficient W _i of the adaptive digital filter W is executed based on the reference signal x and the residual vibration signal e so that the vibration transmitted to the device is reduced.

The updating formula of the adaptive digital filter W is F
The following equation (1) follows the iltered-X LMS algorithm. W _i (n + 1) = W _i (n) −μR ^T e (n) (1) Here, the term with (n) represents a value at time n, and μ is a convergence coefficient. It is a coefficient that is called and is related to the speed of convergence of the filter coefficient W _i and its stability. R ^T is theoretically the transfer function C between the reference signal x and the electromagnetic actuator 10 and the acceleration sensor 22.
Is a value (reference signal or Filtered-X signal) filtered by the transfer function filter C ^ that is modeled as, but in this embodiment, it is a synchronous Filtered-XL.
As a result of applying the MS algorithm, since the reference signal x is an impulse train, the impulse response waveforms of the transfer function filter C ^ coincide with the sum at the time n when the impulse responses are sequentially generated in synchronization with the reference signal x. .

Further, theoretically, the reference signal x is filtered by the adaptive digital filter W to generate the control signal y, and the filtering process corresponds to the convolutional calculation in the digital calculation. Since it is an impulse train, even if each filter coefficient W _i of the adaptive digital filter W is sequentially output as the control signal y at a predetermined sampling clock interval from the time when the latest reference signal x is input as described above. , The same result as when the filtering result is the control signal y.

FIG. 2 is a circuit diagram showing a specific connection relationship between the exciting coil 10B, the drive circuit 19 and the controller 20. The drive circuit 19 of the present embodiment has a power supply _{Vcc of} about 12V and a ground. Is composed of an H-type bridge circuit in which four MOS transistors (specifically, MOS (Metal Oxide Semiconductor) transistors in which a Zener diode is connected between the drain and the source) 19a to 19d are combined. Specifically, a MOS transistor 19a arranged in series between the power supply _Vcc and ground.
Exciting coil 10B between the MOS transistor 19d and the MOS transistor 19d
Of the exciting coil 10B is connected between the MOS transistor 19b and the MOS transistor 19c which are connected in series between the power source _Vcc and the ground. Then, each MOS transistor 19a
The control signal y from the controller 20 to the gates of ~ 19d.
_{1 to} y ₄ are input. The control signals y _{1 to} y ₄ are the control signals y determined as described above.
Is a control signal for the drive circuit 19 of the present embodiment, which is uniquely determined in the controller 20 according to the control signal y.
It may be considered that _{1 to} y ₄ are substantially the same.

Here, the power source V_ccTwo MOs located on the side
Input to the gates of the S transistors 19a and 19b
Control signal y₁, Y₂Is the MOS transistor 19
Logical value "1" or cutoff that makes a and 19b conductive.
Digital output that takes one of the logical values "0"
Has become a force. However, the electromagnetic actuator 10
The magnetic path member 12 is displaced to generate an active control force.
While the vibration reduction control is being performed, the MOS transistor 19
A control signal y having a logical value "1" is provided on one of a and 19b. ₁, Y
₂Is input to the other control signal y having a logical value "0".₁, Y₂
Is entered.

The control signals y ₃ and y ₄ input to the gates of the two MOS transistors 19c and 19d located on the ground side have a variable duty ratio D _r and a maximum period (when D _r is 1). The PWM output is a pulse signal (control pulse signal) having a cycle of T _p . That is, the control signals y ₃ and y ₄ are pulse signals that are repeatedly generated with a logical value of “1” and a cycle of T _p × D _r as shown in FIG.

Then, the controller 20 uses the drive circuit 1
And the MOS transistors 19a and 19c at one diagonal position of the bridge circuit 9 and the MO at the other diagonal position of the bridge circuit of FIG.
The S transistors 19b and 19d are set as a pair to output the control signals y _{1 to} y ₄ . That is, the controller 20 outputs the control signal y ₁ having a logical value of “1” to the MOS transistor 19a, and
If the control signal y ₃ which is a pulse signal having the duty ratio D _r is output to the S transistor 19c, but the control signals y ₂ and y ₄ are not output to the MOS transistors 19b and 19d, the MOS transistor 19a becomes conductive. , The MOS transistor 19c is turned on during the maximum period T _p for a time corresponding to the duty ratio D _r , and M
Since the OS transistors 19b and 19d are cut off, a drive current I _A indicated by an arrow pointing to the right in FIG. 2 flows through the exciting coil 10B, and the magnitude (conduction time) of the drive current I _A is the duty ratio. It depends on D _r . On the other hand, the controller 20 outputs the control signal y ₂ having the logical value “1” to the MOS transistor 19b and the control signal y _{4 including} the pulse signal having the duty ratio D _r to the MOS transistor 19d.
Control signals y ₁ , to the MOS transistors 19a and 19c,
If y ₃ is not output, the MOS transistor 19b is turned on, the MOS transistor 19d is turned on for a time period corresponding to the duty ratio D _r during the maximum period T _p , and the MOS transistors 19a and 19c are turned off. Therefore, the drive current I _B indicated by the arrow pointing to the left in FIG.
The size of _B (conduction time) is determined by the duty ratio D _r .

That is, the controller 20 appropriately outputs the control signals y _{1 to} y ₄ according to the control signal y,
The exciting coil 10B of the electromagnetic actuator 10 is the direction and conduction time adjustment drive current I (I _A, I _B) is supplied. Then, the duty ratio D _{r of} the control signals y ₃ and y ₄ determines the time ratio during which the drive currents I _A and I _B are flowing to the exciting coil 10B. Therefore, by appropriately adjusting the duty ratio D _r , The magnitude of the displacement amplitude of the magnetic path member 12 can be controlled. Therefore, in the controller 20, when the vibration reduction control by the adaptive control is executed, the duty ratio D _r changes according to the amplitude of the vibration input to the engine mount 1, and the duty ratio D _r changes according to the magnitude of the amplitude of the input vibration. As a result, the displacement amplitude of the magnetic path member 12 changes, so that a control force having a magnitude corresponding to the amplitude of vibration is generated.

Further, as will be described later in detail with reference to the flow chart, the controller 20 has a direction in which the change of the control signal y becomes steep when the absolute value of the obtained control signal y approaches 0. The correction process is executed. Next, the operation of this embodiment will be described. That is, when the engine shake occurs, the flow path shape of the orifice 5a is appropriately selected. As a result, the engine mount 1 functions as a support device for high dynamic spring constant and high damping force. Is damped by the engine mount 1, and the vibration level on the member 35 side is reduced. In such a case, it is not necessary to specifically displace the magnetic path member 12.

On the other hand, when the vibration in the frequency higher than the idle vibration frequency is input, which makes the fluid in the orifice 5a stick and the fluid cannot move between the fluid chamber 15 and the sub-fluid chamber 16, 20 executes a predetermined arithmetic processing, outputs a control signal y to the electromagnetic actuator 10, and causes the engine mount 1 to generate an active control force capable of reducing vibration.

This will be specifically described with reference to FIGS. 4 and 5 which are flowcharts showing the outline of the processing executed in the controller 20 when the idle vibration and the muffled sound vibration are input. First, after predetermined initialization is performed in step 101, the process proceeds to step 102, and the reference signal R ^T is calculated based on the transfer function filter C ^. In this step 102, the reference signals R ^{T for} one cycle are collectively calculated.

Then, after shifting to step 103 and the counter i is cleared to zero, the routine proceeds to step 104,
I-th filter coefficient W _{i of the} adaptive digital filter W
Is output as the control signal y. However, in the present embodiment, what is output as the control signal y in step 104 is not the filter coefficient W _i itself but the filter coefficient W _i ′ after the correction calculation described below is performed.

When the control signal y is output in step 104, the process proceeds to step 105, the residual vibration signal e is read, the counter j is cleared to zero in step 106, and then the process proceeds to step 107, where j of the adaptive digital filter W is read. The th filter coefficient W _j is updated according to the above equation (1). When the update process in step 107 is completed, the process proceeds to step 108, and it is determined whether or not the next reference signal x is input. If it is determined that the reference signal x is not input, the adaptive digital signal is input. In order to update the filter coefficient next to the filter W or output the control signal y, the process proceeds to step 109.

In step 109, it is determined whether or not the counter j has reached the output count T _y (more precisely, since the counter j starts from 0, the output count T _y minus 1). In this determination, in step 104, the filter coefficient W _i 'of the adaptive digital filter W is set to the control signal y.
After that, it is for determining whether or not the filter coefficient W _i of the adaptive digital filter W has been updated by the necessary number as the control signal y. Therefore, if the determination in step 109 is “NO”, step 1
After the counter j is incremented in 10, the process returns to step 107 and the above-described processing is repeatedly executed.

However, the determination in step 109 is "YE
In the case of “S”, it can be determined that the updating process of the necessary number of filter coefficients among the filter coefficients of the adaptive digital filter W has been completed as the control signal y.
The process shifts to 1 to execute a subroutine that is a process of correcting the filter coefficient of the adaptive digital filter W. The processing of step 111 will be described later.

After the processing of step 111 is completed, the process proceeds to step 112, and it is determined again whether or not the reference signal x is input. If it is determined in step 112 that the reference signal x is not input, , The process proceeds to step 113, the counter i is incremented, the process of step 104 is executed, and then a predetermined sampling
Wait until the time corresponding to the clock interval has elapsed,
When the time corresponding to the sampling clock has elapsed,
Returning to step 104, the above-mentioned processing is repeatedly executed.

However, if it is determined in step 108 or 112 that the reference signal x is input, step 1
14, the counter i (to be exact, the counter i is 0
Since it is started from, the value obtained by adding 1 to the counter i) is stored as the latest output count T _y , and then step 10
Returning to step 2, the above processing is repeatedly executed. As a result of repeatedly executing the processing of FIG. 4, the reference signal x,
FIG. 6 showing the relationship between the control signal y and the transfer function filter C ^.
As shown in FIG. 5, the filter coefficient W _i (correctly, corrected) of the adaptive digital filter W is input to the driving circuit 19 from the controller 20 at the sampling clock interval from the time when the reference signal x is input. The filtered filter coefficient W _i 'after the control signal y (control signal y ₁ ~
y ₄ ).

As a result, the magnetic force corresponding to the drive signal y is generated in the exciting coil 10B by the drive circuit 19 which is the H-shaped bridge circuit, but the permanent magnet 1 is already formed in the magnetic path member 12.
Since a constant magnetic force of 0C is applied, it can be considered that the magnetic force of the exciting coil 10B acts to strengthen or weaken the magnetic force of the permanent magnet 10C. That is, in the state where the drive signal y is not supplied to the exciting coil 10B, the magnetic path member 12 is displaced to a neutral position where the supporting force of the leaf spring 11 and the magnetic force of the permanent magnet 10C are balanced. When the drive signal y is supplied to the exciting coil 10B in this neutral state, if the magnetic force generated in the exciting coil 10B by the drive signal y is in the opposite direction to the magnetic force of the permanent magnet 10C, the magnetic path member 12 is It is displaced in a direction in which the clearance with the electromagnetic actuator 10 increases. On the contrary, if the magnetic force generated in the exciting coil 10B is in the same direction as the magnetic force of the permanent magnet 10C, the magnetic path member 12 is displaced in the direction in which the clearance with the electromagnetic actuator 10 decreases.

As described above, the magnetic path member 12 can be displaced in both the forward and reverse directions. If the magnetic path member 12 is displaced, the main fluid chamber 15 can be moved.
The volume of the engine mount 1 changes, and the expansion spring of the support elastic body 6 deforms due to the change in the volume, so that an active support force in both the forward and reverse directions is generated in the engine mount 1. Then, each filter coefficient W _i of the adaptive digital filter W serving as the drive signal y is a synchronous Filtered-X LM.
Since it is sequentially updated by the above formula (1) according to the S algorithm, after a certain amount of time has passed and each filter coefficient W _i of the adaptive digital filter W has converged to the optimum value, the drive signal y is changed to the engine mount 1 Is supplied to the member 35, the idle vibration and the muffled sound vibration transmitted to the member 35 side via the engine mount 1 are reduced.

Here, the correction processing of the filter coefficient of the adaptive digital filter W in step 111 will be described. That is, FIG. 5 is a flowchart showing an outline of the subroutine processing in step 111. First, in step 201, is T _y, which is the latest output count of the control signal y, exceeding a predetermined value β (for example, 8)? If it is determined that it does not exceed, the subsequent processing is not executed in step 202, that is, the filter coefficient of the adaptive digital filter W is not corrected,
The process shown in FIG. 5 is terminated and the process returns to the process of FIG.
This is because in the correction processing of the filter coefficient of the adaptive digital filter W, the number of outputs T _y represents how many control signals y are output within the cycle of one cycle processing (cycle of the reference signal x). If the number of outputs T _y does not reach the predetermined value β, it can be determined that the sampling clock is in a coarse state with respect to the vibration frequency, and the filter coefficient of the adaptive digital filter W is corrected in such a situation. On the contrary, it is feared that the vibration reduction control is adversely affected.

If the determination in step 201 is "YES", the process proceeds to step 202 and the maximum value W is selected from the filter coefficients W _{0 to} W _Ty-1 of the adaptive digital filter W.
_max , minimum value W _min , and two zero-cross points W
Find _z1 and W _z2 . The cello cross points W _z1 and W _z2 are, of the filter coefficients W _{0 to} W _Ty-1 , the filter coefficient at the moment when the magnitude becomes 0 or the filter coefficient immediately before becoming 0.

Next, the routine proceeds to step 203, where the output frequency T _y corresponding to the vibration frequency and the maximum control output value (absolute value of the maximum value W _max and the minimum value W _min ) corresponding to the vibration amplitude are determined. Then, for example, with reference to a table as shown in FIG. 7, the correction amounts δ _{0 to} δ for the respective filter coefficients W _{0 to} W _Ty-1.
Determine _Ty-1 . In the table of FIG. 7, it is assumed that the first filter coefficient W ₀ has the maximum value W _max , the correction amount δ ₀ at that time is 0, and the first filter coefficient W 0
_{After 0} , the correction amount δ _i increases as the filter coefficient W _i changes in the negative direction, and the correction amount δ _i becomes 0 at the moment when the zero cross point W _Z1 is crossed, and then reaches the minimum value W _min . Until the correction amount δ _i remains 0,
Then, as the filter coefficient W _i approaches 0 from the minimum value W _min , the correction amount δ _i increases, and at the moment when the zero cross point W _Z2 is exceeded, the correction amount δ _i becomes 0, and from there, the maximum value W _max. It remains at 0 until. Therefore, the maximum value W _max , the minimum value W _min, and the zero cross points W _z1 , W obtained in step 202
Depending on the position of _z2, the correction amount δ _i obtained from FIG. 7 needs to be appropriately shifted.

Further, as is clear from FIG. 7, the correction amount δ _i becomes larger as the control output maximum value (vibration amplitude) becomes larger, and as the output count T _y (vibration cycle) becomes longer. It has a small value (that is, increases as the frequency of vibration increases).
Then, the correction amount δ _i as shown in FIG. 7 is set in advance to an optimum value for each maximum control output value and each output number T _y by experiments or the like.

When the correction amount δ _i is determined, step 20
4, the correction calculation of each filter coefficient W _i of the adaptive digital filter W is performed. Specifically, the filter coefficient W _i between the maximum value W _max and the near zero-cross point W _z1 is corrected by subtracting the correction amount δ _i from the filter coefficient W _i according to the following equation (2). The filter coefficient W _i between the minimum value W _min and the zero cross point W _z2 close to the minimum value W _min is corrected by adding the correction amount δ _i to the filter coefficient W _i according to the following equation (3). Done. For other areas, the correction amount δ _i is 0, so the correction calculation is not performed. That is, the correction calculation is performed only on the filter coefficient W _i in the area where the absolute value decreases. W _i ′ = W _i −δ _i (2) W _i ′ = W _i + δ _i (3) When the process of step 204 is finished, the process shown in FIG. 5 is finished and the process of FIG. Return to.

As a result of the correction processing shown in FIG. 5,
The waveform drawn by the filter coefficient W _i before correction is shown in FIG.
Even if the waveform is represented by the corrected filter coefficient W _i ′ even if it is substantially sinusoidal as shown in (a), the change of the filter coefficient W _i is within the range in which the absolute value of the filter coefficient W _i decreases. Since the correction calculation is performed in the steep direction, it becomes as shown in FIG. Specifically, the corrected filter coefficient W _i ′ reaches the size 0 on the front side of the zero cross points W _Z1 and W _Z2 of the uncorrected filter coefficient W _i on the time axis, and from there, the zero cross point. W _Z1
And W _Z2 change sharply until the point on the same time axis as W _Z2 is reached, and when the point on the same time axis as zero cross points W _Z1 and W _Z2 is reached, it returns to the same value as the filter coefficient W _i. There is.

That is, the corrected filter coefficient W _i 'is
0 in the decreasing region as compared with the filter coefficient W _i before correction
The directivity to is becoming stronger. Therefore, when the corrected filter coefficient W _i ′ is output as the control signal y in step 104, the corrected filter coefficient W _i ′ is output.
The duty ratio D _r of the control signals y ₃ and y ₄ is corrected by _i ′ so as to be smaller than the original value, and the drive circuit 1
The drive current I flowing in the exciting coil 10B of the electromagnetic actuator 10 is eliminated or reduced as described above in FIG. 9, and the control signal y before correction, which is a desirable waveform, is drawn as shown in FIG. 8C. The waveforms are matched or substantially matched, and the generation of the high frequency vibration as shown in FIG. 9C in the magnetic path member 12 is avoided.

Therefore, according to the structure of this embodiment, no abnormal noise is generated by the high frequency vibration of the magnetic path member 12, and the high frequency vibration is not superposed on the magnetic path member 12.
It is not necessary to cause the deterioration of the image stabilization control performance, which has been a problem in the past. Moreover, in order to obtain such an advantage, it is not necessary to newly provide various parts such as an A / D converter, a monitor resistor, a comparator, a low-pass filter, etc., so that a large increase in cost and device There is an advantage that it does not cause an increase in size. In particular, the fact that the size of the device is not increased is very desirable for a vehicle having a large mounting space constraint.

Here, in the present embodiment, the control signal correction means is constituted by the processing shown in FIG. In addition, although the above-mentioned embodiment shows the case where the anti-vibration support device according to the present invention is applied to the engine mount 1 that supports the engine 30, the application target of the anti-vibration support device according to the present invention is the engine mount 1. However, the present invention is not limited to this, and may be, for example, a vibration isolation support device for a machine tool accompanied by vibration.

Further, in the above embodiment, the drive signal y is generated according to the synchronous Filtered-X LMS algorithm, but the applicable algorithm is not limited to this, and for example, a normal Filtered-X LMS algorithm is used.
It may be an X LMS algorithm or a frequency domain LMS algorithm. Further, if the system characteristics are stable, the drive signal y is adjusted by a fixed coefficient digital filter or analog filter without using an adaptive algorithm such as the LMS algorithm.
May be generated.

In the above embodiment, the control signal y is 0.
Although the description has been given of the case of oscillating in both the positive and negative directions with respect to the center (that is, the case where the control signal y does not include the DC component), for example, when the magnetic path member 12 is offset by the magnetic force generated by the exciting coil 10B. As described above, when the control signal y includes a DC component, the filter coefficient W
Before performing the correction process of _i , only the AC component is extracted therefrom, and the same correction process as that in the above-described embodiment is performed on the AC component. The correction result and the filter coefficient W _i before the correction
The control signal y may be obtained by superimposing the DC component of the above.

Further, the drive circuit 19 is not limited to the PWM type drive circuit as in the above embodiment, and may be a circuit of another type. Furthermore, in the above-described embodiment, the vibration damping effect is obtained by utilizing the fluid resonance generated when the fluid passes through the orifice 5a when the low frequency vibration is input, but such a low frequency vibration is not input. In the case of the anti-vibration support device that supports the vibrating body, it is not necessary to provide the orifice component 5, the diaphragm 4, etc., and the number of parts is reduced accordingly, so that the cost is reduced.

[0059]

As described above, according to the first aspect of the present invention, when the absolute value of the AC component of the control signal generated and output by the control means decreases, the control signal correction means controls the control signal. Since the AC component of the signal is corrected so that its change becomes steep, the delay amount when the drive current is delayed with respect to the control signal does not cause a significant increase in cost or the size of the device. Since the control signal is corrected in the decreasing direction and the delay of the drive current is eliminated or reduced, there is an effect that a desired drive current is accurately supplied to the exciting coil of the electromagnetic actuator and a good vibration reducing effect is obtained.

In particular, according to the invention of claim 2, since the correction amount is set according to the delay state, the effect of the invention of claim 1 can be surely obtained. Further, according to the invention of claim 3, even in the PWM type drive circuit in which the delay is a problem, a good vibration reducing effect can be obtained by the actions of the inventions of claims 1 and 2. it can.

Further, according to the invention of claim 4, it can be made to act as a normal fluid-filled type vibration-damping support device for generating a passive support force, so that a vibration-damping effect against various vibrations can be obtained. There is an effect that can be exhibited.

[Brief description of drawings]

FIG. 1 is a sectional view showing the overall configuration of an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a configuration of a drive circuit.

FIG. 3 is a waveform diagram of control signals y ₃ and y ₄ .

FIG. 4 is a flowchart showing an outline of processing executed in the controller.

FIG. 5 is a flowchart showing an outline of processing executed in the controller.

FIG. 6 is a waveform diagram of a reference signal x, a control signal y, and a transfer function filter C ^.

FIG. 7 is a diagram showing an example of a table for determining a correction amount δ _i .

FIG. 8 is a waveform diagram of a filter coefficient W _i before correction, a filter coefficient W _i ′ after correction, and a drive current I.

FIG. 9 is a waveform diagram for explaining conventional problems.

[Explanation of symbols]

 1 engine mount (anti-vibration support device) 4 diaphragm 5a orifice 6 support elastic body 8 actuator case 10 electromagnetic actuator 11 leaf spring 11b central part (movable member) 12 magnetic path member (movable member) 15 fluid chamber 16 sub-fluid chamber 19 drive Circuits 19a to 19d MOS transistor 20 Controller (control means) 21 Pulse signal generator 22 Acceleration sensor

Claims (4)

[Claims] 1. A support elastic body interposed between a vibrating body and a support body, a fluid chamber defined by the support elastic body, a fluid enclosed in the fluid chamber, and a part of a partition wall of the fluid chamber. And a magnetizable movable member elastically supported so as to form a magnetic field, an electromagnetic actuator that generates a magnetic force that displaces the movable member in a direction in which the volume of the fluid chamber changes, and a drive current that corresponds to a control signal to the electromagnetic A drive circuit that supplies the exciting coil of the actuator, a control unit that generates and outputs the control signal so as to reduce the vibration on the support side, and a control signal when the absolute value of the AC component of the control signal decreases. And a control signal correcting unit that corrects the AC component of the AC component in a direction in which the change is sharp. 2. The anti-vibration support device according to claim 1, wherein the control signal correction means sets the correction amount according to the amplitude and frequency of the AC component of the control signal before correction. 3. The drive circuit is a pulse width modulation type drive circuit, the control signal is a control pulse signal with a variable duty ratio, and the control signal correction means corrects the duty ratio of the control pulse signal. Item 1 or claim 2
Anti-vibration support device described. 4. A variable-volume auxiliary fluid chamber communicating with the fluid chamber via an orifice is provided.
The anti-vibration support device according to any one of claims 1 to 3, wherein a fluid is enclosed in the orifice and the sub-fluid chamber.