JPH10141426A - Vibrationproof device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a manufacturing cost for a vibrationproof device by utilizing negative pressure. SOLUTION: A movable plate 56 which constitutes a bulkhead on a lower side of a pressure receive liquid chamber 46 is linked with a bulkhead plate 58, and a coil spring 74 which energizes the bulkhead plate 58 and the movable plate 54 upward and integrally is arranged in an expansion and shrinkage air chamber 72 formed below the bulkhead plate 58. The expansion and shrinkage air chamber 72 is connected with a three-port two-position change-over valve 82 through a communicating pipe 76 and a pipe 78. The three-port two-position change-over valve 82 is connected with a connection pipe 86 which is communicated with an intake manifold 84, of an engine and an external air communicating pipe 88 which is communicated with the atmosphere, and the three-port two-position change-over valve 82 is changed over between these pipes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration isolator for reducing vibration by active control, and is particularly suitable for an engine mount or the like.

[0002]

2. Description of the Related Art An engine of a vehicle, which is a vehicle, is supported on a vehicle body by a vibration isolator which is an engine mount, and this vibration isolator prevents transmission of engine vibration to the vehicle body. And as an example of such a vibration isolator,
An active mount for performing active control as shown in FIG. 2 has been proposed, and a conventional anti-vibration device will be described with reference to FIG.

In the vibration isolator shown in this figure, a sub-liquid chamber 244 is communicated via a restriction passage 247 to a pressure-receiving liquid chamber 245 whose internal volume changes due to deformation of an elastic body 228. Further, a leaf spring 224 serving as a partition wall of the pressure receiving liquid chamber 245 is attached to a lower side of the pressure receiving liquid chamber 245, and an actuator for reciprocating the leaf spring 224 to an attachment member 212 for attaching the vibration isolator to an engine or a vehicle body. An electromagnet 250 is attached.

When the leaf spring 224 is reciprocated, it is necessary to form a magnetic path of a magnetic flux applied from the electromagnet 250 to the leaf spring 224 side. 224 by screwing.

Accordingly, in the vibration isolator having such a structure, when the mounted engine is operated to generate vibration, the deformation of the elastic body 228 and the liquid in the restriction passage 247 communicating between the liquid chambers 244 and 245 are performed. The vibration is absorbed by the viscous resistance and the like, and the leaf spring 224 is reciprocated by the electromagnetic force generated by the electromagnet 250 so that the liquid pressure in the pressure receiving liquid chamber 245 does not increase. Vibration is absorbed without increasing the dynamic spring constant.

[0006]

However, in the above-described vibration damping device, an expensive electromagnet 250 is used for reciprocating the leaf spring 224, and the leaf spring 2 is used for manufacturing.
Since a large amount of labor is required for screwing the ferromagnetic material 230 to the screw 24, the manufacturing cost of the vibration isolator is disadvantageously increased.

In order to generate a driving force, the electromagnet 25
It is necessary to appropriately maintain the clearance between the ferromagnetic material 230 and the ferromagnetic material 230, and the strength of the leaf spring 224 is reduced by the mounting hole 226 formed when the ferromagnetic material 230 is screwed to the leaf spring 224. , Durability may be reduced. Therefore, the structure relating to the leaf spring 224 and the ferromagnetic material 230 is precise and complicated, and the vibration isolator is increased in size, resulting in a further increase in the manufacturing cost of the vibration isolator.

The present invention has been made in view of the above circumstances, and has as its object to provide an anti-vibration device which uses a negative pressure to reduce manufacturing costs.

[0009]

According to a first aspect of the present invention, there is provided a vibration isolator which is connected to one of a vibration generator and a vibration receiver, and connected to the other of the vibration generator and the vibration receiver. A second mounting member, an elastic body provided between the first mounting member and the second mounting member, and a liquid filled therein, and the elastic body expands / contracts when vibration occurs as a part of the partition wall. A pressure-receiving liquid chamber, a sub-liquid chamber connected to the pressure-receiving liquid chamber via a restriction passage, a movable member configured to displace another part of the partition wall of the pressure-receiving liquid chamber, and reciprocating movement of the movable member. An actuator for generating an exciting force to be generated by a negative pressure, and control means for driving the actuator to reciprocate the movable member are provided.

According to a second aspect of the present invention, in the vibration isolator according to the first aspect, the actuator is provided with a switching valve capable of stopping a negative pressure, and an elasticity for constantly biasing the movable member toward the pressure receiving liquid chamber. The movable member is sucked while the elastic member is deformed in a negative pressure state and moves to the opposite side to the pressure receiving liquid chamber, and the movable member is biased by the elastic member in a state where the negative pressure is stopped. Is moved back to the pressure receiving liquid chamber side.

The operation of the vibration isolator according to claim 1 will be described below. One of the first mounting member and the second mounting member of the vibration isolator is connected to the vibration generating unit, and the other is connected to the vibration receiving unit. When vibration is input from the vibration generator to the vibration isolator, the elastic body is deformed and the pressure-receiving liquid chamber expands and contracts. As a result, in addition to the vibration being absorbed by the resistance based on the internal friction of the elastic body, the liquid in the pressure receiving liquid chamber moves back and forth between the auxiliary liquid chamber and the auxiliary liquid chamber via the restriction passage, and a damping force is generated. Vibration is difficult to be transmitted.

Further, when a vibration that causes the restriction passage to be clogged is input from the vibration generating unit side, an actuator that generates a vibrating force by a negative pressure is controlled by the control means to be driven to be displaceable. The movable member, which is supported and forms a part of the partition wall of the pressure receiving liquid chamber, is reciprocated while being sucked by the actuator at a negative pressure, thereby suppressing an increase in the liquid pressure in the pressure receiving liquid chamber.

As a result, even if the frequency of vibration increases and the restriction passage becomes clogged, the movable member reciprocates and suppresses an increase in the liquid pressure in the pressure receiving liquid chamber. In addition, the vibration transmitted to the vibration receiving portion can be reduced by reliably absorbing the vibration.

As described above, since an electromagnet is not used as an actuator, it is not necessary to reciprocate a heavy movable member by electromagnetic force, for example, only by opening and closing a pipe through which air passes.
The movable member can reciprocate. For this reason, an electromagnet and a ferromagnetic material, which cause a high manufacturing cost, are not used, and a large load is not applied to the vibration isolator, so that the structure can be simplified and the vibration isolator can be downsized. Thus, a low-cost vibration damping device can be provided.

The operation of the vibration isolator according to claim 2 will be described below. The present invention has the same configuration as that of the first aspect, and thus has the same effect. However, in the present invention, the movable member is sucked while the elastic member is deformed in the negative pressure state, moves to the opposite side to the pressure receiving liquid chamber, is switched by the switching valve, and the elastic member is stopped in the state where the negative pressure is stopped. The movable member is moved so as to return to the pressure receiving liquid chamber side by the urging force.

Accordingly, since the actuator has a simple structure including the switching valve and the elastic member, the cost of the vibration isolator can be further reduced.

[0017]

FIG. 1 shows an embodiment of a vibration isolator according to the present invention, and the present embodiment will be described with reference to FIG.

As shown in FIG. 1, this vibration isolator main body 10
Is provided with a cup-shaped lower mounting base 12 as a first mounting member. A disk-shaped bottom plate 12B is formed on the bottom surface of the lower mounting base 12, and mounting bolts 14 are erected on the bottom plate 12B. A cylindrical upright wall portion 12A is erected around the bottom plate 12B, and a flange portion 12C extending radially outward is formed at an upper end portion of the upright wall portion 12A.

In this embodiment, the lower mounting base 12 is mounted on a vehicle body 16 of an automobile, and a nut 18 is screwed into the mounting bolt 14 so that the lower mounting base 12 is fixedly connected to the vehicle body 16. Have been.

On the other hand, the flange portion 12C of the lower mounting base 12
A ring-shaped support bracket 22 is located at the upper part of the steel connection ring, and a steel connection ring 5 formed in a ring shape and bent toward the inner peripheral side via a pair of O-rings 24 therebetween.
2 are pinched.

A movable plate 54, which is a movable member made of metal in a disk shape, is disposed inside the connection ring 52. The movable plate 54 and the connection ring 5 are formed in an annular shape.
Rubber elastic support member 56 that connects the two by vulcanization bonding.
Support the movable plate 54 so as to be elastically displaceable.

Below the movable plate 54, a metal partition plate 58 whose central portion protrudes one step upward is disposed, and is joined to the movable plate 54 and the partition plate 58 by welding or the like. A connecting rod 60 integrally connects the movable plate 54 and the partition plate 58. Therefore, the movable plate 54 and the partition plate 58 reciprocate vertically in FIG.

The outer peripheral side of the partition plate 58 and the lower mounting base 12
Between the fitting fitting 62 fitted to the inner peripheral surface of the upright wall portion 12A, there is disposed a rubber elastic film member 64 formed in an annular shape and vulcanized and adhered thereto, respectively. The elastic film member 64 supports the partition plate 58 so as to be elastically displaceable.

Accordingly, in the space between the movable plate 54 and the partition plate 58, an intermediate air chamber 66 is formed in which the space between the movable plate 54 and the space above the movable plate 54 is sealed by the elastic support member 56, A through-hole 68 is formed in the fitting 12 and the fitting 62 so as to penetrate them and make the inside of the intermediate air chamber 66 atmospheric pressure.

In a space between the partition plate 58 and the bottom plate 12B of the lower mounting base 12, an expansion / contraction air chamber 72 is formed in which the space between the partition plate 58 and the intermediate air chamber 66 is sealed by the elastic film member 64. Between the partition plate 58 and the bottom plate 12B of the lower mounting base 12, a coil spring 74, which is an elastic member that urges the partition plate 58 and the movable plate 54, which are connected via the connecting rod 60, integrally upward, is disposed. Have been.

Further, a pipe 7 is provided at the lower end side of a communication pipe 76 inserted into the bottom plate 12B of the lower mounting base 12, which is the bottom face of the expansion / contraction air chamber 72, and the vehicle body 16 so as to communicate therewith.
One end of the pipe 8 is connected, and the other end of the pipe 78 is connected to a three-port two-position switching valve 82. Therefore, the expansion / contraction air chamber 72 is connected to the three-port two-position switching valve 82 via the communication pipe 76 and the pipe 78.

On the other hand, at the outer peripheral side of the movable plate 54 and at a position coaxial with the movable plate 54, an outer tube fitting 26 formed in a cylindrical shape is disposed. The outer tube fitting 26 has a shape in which the inner and outer diameters are increased as going upward.
An elastic body 28, which is a rubber body and is formed in a ring shape, is vulcanized and bonded to the inner peripheral side of the outer cylinder fitting 26. And
A part of the elastic body 28 is thinly extended to near the lower end of the inner periphery of the outer metal fitting 26.

A flange 26A extending radially outward is provided at the lower end of the outer tube fitting 26. The outer peripheral side of the flange 26A is narrowed inward, and the flange 12C of the lower mounting base 12 is closed. Between the outer cylindrical metal fitting 26 and the connecting ring 52 and the support fitting 22 respectively.
And the lower mounting base 12 are fixed to each other.

On the other hand, a fixing portion 30 formed in a cup shape is provided at the center of the elastic body 28. A flange portion 30B is formed at the upper end of the fixing portion 30 and extends outward. The inner peripheral side of the elastic body 28 is vulcanized and bonded from the outer peripheral surface of the cylindrical portion 30A to a part of the flange portion 30B.

Further, on the upper side of the fixing portion 30, an air chamber forming portion 3 as a second mounting member formed in a substantially hat shape is provided.
2 is disposed, and a flange portion 32A provided at a lower end of the air chamber forming portion 32 is provided with a flange portion 30B of the fixing portion 30.
The air chamber forming part 32 is fixed to the fixing part 30 by crimping. A diaphragm 34, which is an elastic film made of rubber, is disposed between the fixing portion 30 and the air chamber forming portion 32. A peripheral portion of the diaphragm 34 has a flange portion 30B of the fixing portion 30 and the air chamber. It is sandwiched between the flange 32 </ b> A of the forming part 32.

The air chamber forming part 32 and the diaphragm 3
An air space 36 is formed between the air chamber 4 and the inside, and the inside is communicated with outside air as needed. A mounting bolt 38 for mounting the engine is provided upright on the upper shaft core of the air chamber forming portion 32.

An engine bracket 40 mounted on an engine (not shown) is mounted on the air chamber forming section 32. A nut 42 is screwed into a mounting bolt 38 that penetrates the engine bracket 40, whereby the air is formed. The chamber forming part 32 is connected to the engine while being fixed.

On the other hand, the space between the fixed portion 30 and the diaphragm 34 is a sub liquid chamber 44, and the space between the fixed portion 30 and the movable plate 54 is a partition wall for the elastic body 28 and the movable plate 54. Is formed as a part of the pressure receiving liquid chamber 46.

A thin, cylindrical passage forming member 48 whose lower side is sealed is fitted and fixed inside the fixing portion 30. A concave portion 48 </ b> A that forms the restriction passage 50 is formed on the lower outer peripheral side of the passage forming member 48. One end of the restriction passage 50 is connected to the pressure receiving liquid chamber 46, and the other end is connected to the sub liquid chamber 44. Therefore, the restriction passage 50
Communicates between the pressure receiving liquid chamber 46 and the auxiliary liquid chamber 44.

The pressure receiving liquid chamber 46 and the sub liquid chamber 44 are filled with a liquid such as ethylene glycol.

On the other hand, as shown in FIG. 1, the above-mentioned three-port two-position switching valve 82 is connected to a connection pipe 86 communicating with an intake manifold 84 of an engine (not shown) and an outside air communication pipe 88 communicating with outside air, respectively. ing.

The three-port two-position switching valve 82 is a so-called solenoid valve having a built-in solenoid. The three-port two-position switching valve 82 determines the driving condition of the vehicle and the switching timing of the three-port two-position switching valve 82, and outputs a voltage of 12 volts. The three-port two-position switching valve 82 is connected to a control device 92 that can perform switching control that can apply at an arbitrary timing. For this reason, switching of supply and distribution of gas into the expansion / contraction air chamber 72 connected to the three-port two-position switching valve 82 is performed by the control device 9.
It is controlled by applying a voltage from 2 to the 3-port 2-position switching valve 82.

Further, a vibration sensor 94 capable of detecting vibration of the vehicle body 16 is attached to the vehicle body 16 as a sensor for determining the driving condition of the vehicle and for determining the switching timing of the three-port two-position switching valve 82. The vibration sensor 94 is connected to the control device 92 so as to send a signal of the detected vibration to the control device 92.

As described above, based on the signal from the vibration sensor 94, the control device 92 controls the energization of the three-port two-position switching valve 82 and the stop of the energization, and accordingly the air pressure in the expansion / contraction air chamber 72 is reduced. As a result, the partition plate 58 and the movable plate 54 move up and down as indicated by arrows.

More specifically, in a state where the three-port two-position switching valve 82 is energized, the intake manifold 84
Is shut off, the expansion / contraction air chamber 72 is communicated with the atmosphere side, and the inside of the expansion / contraction air chamber 72 becomes atmospheric pressure. For this reason,
Partition plate 58 and movable plate 54 serving as partition walls of expansion / contraction air chamber 72
Are pushed up integrally by the coil spring 74.

In the state where the power supply to the three-port two-position switching valve 82 is stopped, the communication with the atmosphere side is cut off, and the expansion / contraction air chamber 72 communicates with the intake manifold 84. Is the intake manifold 84
Is set to a negative pressure. When the interior of the expansion / contraction air chamber 72 is set to a negative pressure, the partition plate 58 and the movable plate 54 are integrally lowered so that the volume of the expansion / contraction air chamber 72 is reduced against the urging force of the coil spring 74. Will be.

That is, the partition plate 58, the expansion / contraction air chamber 72, the coil spring 74, the three-port two-position switching valve 82, and the like constitute an actuator 70 for generating an exciting force for reciprocating the movable plate 54 by negative pressure. Further, the control device 92 and the vibration sensor 94 constitute control means, and the control device 92 controls the driving of the actuator 70 based on a signal from the vibration sensor 94.

Here, the control device 92 does not drive the actuator 70 in the vibration band up to 15 Hz,
In the 50 Hz vibration band, the actuator 70 is driven with the same phase or shifted phase from the input vibration,
The driving of the actuator 70 is controlled.

Next, the operation of the present embodiment will be described. When the engine of the vehicle (not shown) is started, the pressure in the intake manifold 84 becomes negative.

Accordingly, when the vibration of the engine is inputted to the vibration isolator main body 10, the vibration is transmitted to the elastic body 28 via the air chamber forming part 32 and the fixing part 30, whereby the elastic body 28 is elastically deformed. The pressure receiving liquid chamber 46 expands and contracts. As a result, the vibration is absorbed by the resistance based on the internal friction of the elastic body 28 and the liquid in the pressure receiving liquid chamber 46
A large damping force is generated by the liquid flowing back and forth between the auxiliary liquid chamber 44 and the liquid in the restriction passage 50. As a result, among the engine vibrations, the shake vibrations, which are the vibrations in the low frequency range that occur particularly as the vehicle travels, are absorbed, and the vibrations are less likely to be transmitted to the vehicle body 16 side.

At this time, for example, the vibration sensor 94 detects that a shake vibration of less than 15 Hz is input, and
The drive of the actuator 70 is stopped by the control device 92.

On the other hand, when the vehicle is stopped or the like, vibrations in an idle vibration range of, for example, 15 to 50 Hz, in which the vibration frequency is higher than the shake vibration and the restriction passage 50 is clogged, are input. In this case, the vibration sensor 94 detects this, and generates an exciting force by a negative pressure.
0 is driven under the control of the control device 92. As a result, the movable plate 54 forming a part of the partition wall of the pressure receiving liquid chamber 46 is formed.
Are reciprocated by the actuator 70 in the same phase or out of phase with the input vibration, so that an increase in the liquid pressure in the pressure receiving liquid chamber 46 can be suppressed.

That is, for example, when the frequency of vibration rises and liquid stops flowing through the restriction passage 50, for example, 15 to 5
Even if the vibration having a high frequency of 0 Hz is input and the restriction passage 50 is clogged, the vibration isolator main body 10 is actively controlled. As a result, the movable plate 54 is intermittently sucked into the actuator 70 by the negative pressure. The reciprocating motion causes the rise of the liquid pressure in the pressure receiving liquid chamber 46 to be suppressed. Therefore, the dynamic spring constant in the idle vibration region does not increase, and the vibration in the idle vibration region can be reliably absorbed and reduced, and the vibration transmitted to the vehicle body 16 can be reduced.

Specifically, when the elastic member 28 is deformed so that the engine bracket 40 is lowered and the pressure receiving liquid chamber 46 is reduced and the hydraulic pressure is increased, the control device 92 controls the three-port two-position switching valve 82. Is switched to allow the expansion / contraction air chamber 72 and the intake manifold 84 to communicate with each other.
2 is in a negative pressure state. Along with this, the movable plate 54 is sucked while the coil spring 74 is being deformed, and moves to the lower side opposite to the pressure receiving liquid chamber 46 to prevent the hydraulic pressure from rising.

Also, the engine bracket 40 is raised,
The elastic body 2 is expanded so that the pressure receiving liquid chamber 46 is enlarged and the hydraulic pressure is reduced.
When the valve 8 is deformed, the three-port two-position switching valve 82 is switched by the control device 92 so that the expanded / reduced air chamber 72 communicates with the atmosphere side, and the inside of the expanded / reduced air chamber 72 stops the negative pressure. Atmospheric pressure is assumed. Along with this, the movable plate 54 is moved by the urging force of the coil spring 74
It is moved back to the upper side to prevent a decrease in hydraulic pressure.

As described above, the vibration isolator main body 1 of the present embodiment
0 can reliably absorb vibrations over a wide frequency range from shake vibration to idle vibration.

Further, since the vibration isolator of the present embodiment does not use a voice coil, an electromagnet or the like as an actuator, it is not necessary to reciprocate a heavy movable member by electromagnetic force.
For example, the movable member, which is the movable plate 54, can be reciprocated simply by disposing a switching valve in the middle of a pipe through which air passes and switching the switching valve. For this reason, electromagnets and ferromagnetic materials, which cause high manufacturing costs, are not used, and a large load is not applied to the vibration isolator. Thus, a low-cost vibration damping device can be provided.

Since the actuator 70 has a simple structure having the switching valve 82 and the coil spring 74, the cost of the vibration isolator can be further reduced.

In the above-described embodiment, the lower mounting base 12 having the actuator is mounted on the vehicle body. However, the lower mounting base 12 may be mounted on the engine. That is, the actuator may be located on either side of the first mounting member or the second mounting member.

In the above-described embodiment, the partition plate 58 is formed as a separate member from the movable plate 54 which is a movable member. However, these may be formed of the same member.

On the other hand, in the above embodiment, the timing of switching the three-port two-position switching valve 82 and the like are determined by the vibration sensor 94 capable of detecting the vibration of the vehicle body 16, but the engine rotation frequency is detected from the engine itself. By doing
The driving condition of the vehicle and the switching timing of the switching valve may be determined.

Further, in the above embodiment, the purpose of the present invention is to dampen the engine of an automobile. However, the anti-vibration device of the present invention may be used for, for example, the purpose of damping the body of an automobile. It goes without saying that it can be used for other applications. On the other hand, the shape and dimensions of the elastic body and the like are not limited to those of the embodiment.

[0058]

As described above, the vibration isolator according to the present invention has an excellent effect that the manufacturing cost can be reduced by utilizing the negative pressure.

[Brief description of the drawings]

FIG. 1 is a sectional view of a vibration isolator according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a vibration isolator according to the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Vibration isolator main body 12 Lower mounting base (1st mounting member) 28 Elastic body 32 Air chamber formation part (2nd mounting member) 44 Sub liquid chamber 46 Pressure receiving liquid chamber 50 Restriction passage 54 Movable plate (movable member) 70 Actuator 74 Coil spring (elastic member) 82 3-port 2-position switching valve (switching valve) 92 Controller (control means)

Claims (2)

[Claims] A first mounting member connected to one of the vibration generating unit and the vibration receiving unit; a second mounting member connected to the other of the vibration generating unit and the vibration receiving unit; and the first mounting An elastic body provided between a member and the second mounting member; a pressure-receiving liquid chamber filled with liquid and expanding and contracting when vibration occurs as a part of the elastic body as a partition; and a restriction passage in the pressure-receiving liquid chamber. A sub-liquid chamber connected via a movable member configured to be able to displace another part of the partition wall of the pressure-receiving liquid chamber; and an actuator for generating an exciting force for reciprocating the movable member by negative pressure, Control means for driving the actuator so as to reciprocate the movable member. 2. The actuator according to claim 1, wherein the actuator has a switching valve capable of stopping the negative pressure, and an elastic member which constantly urges the movable member toward the pressure receiving liquid chamber, wherein the elastic member is deformed under the negative pressure. The movable member is sucked and moves to the opposite side to the pressure receiving liquid chamber, and the movable member is moved back to the pressure receiving liquid chamber side by the urging force of the elastic member in a state where the negative pressure is stopped. The anti-vibration device according to claim 1, wherein