JP3304554B2 - Liquid filled type vibration damping device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid-filled type vibration damping device, and more particularly to a vibration-proof device having a vibrator in a main chamber in which liquid is filled, and vibrating the vibrator at a specific frequency.
The present invention relates to a liquid-filled type vibration damping device with a vibrator which causes liquid resonance to obtain a low dynamic spring constant with respect to vibration of a specific frequency.

[0002]

2. Description of the Related Art Among anti-vibration devices, particularly in engine mounts for automobiles and the like, an engine as a power source is operated under various conditions from an idling operation state to a maximum rotation speed. To be used, the vibration isolator must be able to handle a wide range of frequencies. In general, vibration isolators as engine mounts are designed to cut off vibrations such as idling vibrations for torque fluctuations caused by explosive combustion of the engine or shakes for resonance phenomena between the engine and the engine mounts. Next, the system is set (tuned). However, in order to prevent (interrupt) these vibrations, it is difficult to avoid the resonance phenomenon by selecting a spring constant, and it is difficult to avoid the resonance phenomenon. It is conceivable that the vibration is blocked to the side. In order to cope with these plural conditions, two liquid chambers are provided inside, and an orifice is connected between them, and the diameter of the orifice can be changed to cope with the so-called variable characteristic method. A fluid-filled engine mount device has already been devised.
It is publicly known from Japanese Patent No. 0231 and the like.

[0003] The above-mentioned known device is provided with two orifices in order to cope with two types of input vibrations in a low frequency range, and by operating these orifices, two types of vibrations, for example, are provided. The engine idle vibration and the engine shake can be handled (vibration cutoff). However, these vibrations have frequencies between 10 Hz and 30 Hz.
Hz. By the way, automobile engines are used in various situations, and the frequency range of vibration and noise propagated into the vehicle interior via the engine and an engine mount supporting the engine is also wide. I have. In particular, recently, in addition to the idling vibration and the engine shake, vibration / noise related to engine noise such as muffled sound, which is a vibration in a higher frequency range (100 to 300 Hz) than these, has become a problem. In order to cut off these relatively high-frequency vibrations, it is necessary to form a low dynamic spring constant (low dynamic spring characteristics) in these frequency ranges. In order to obtain the low dynamic spring characteristic, a vibrator (voice coil) is provided in the liquid chamber, and by vibrating the vibrator, liquid resonance is performed.
It has already been disclosed in, for example, Japanese Patent No. 39481.

[0004]

However, this conventional device has a structure as shown in FIG. 4, for example, and has the following problems. That is, among the vibrations propagated from the vibrating body side via the connection fitting 910, the vibration of the high frequency region related to the muffled sound is affected by the action of the insulator 50 and the liquid chamber formed by the main chamber 60 and the sub chamber 70. The vibration is shut off by the action of the liquid. And in this case,
First, by passing an alternating current through the exciting coil 110, the exciting coil 110 and the bobbin 150 in which the exciting coil 110 is housed are vibrated with respect to the permanent magnet 130. In particular, by appropriately controlling the value of the alternating current flowing through the excitation coil 110, the vibrator 10 including the bobbin 150 and the like is vibrated at a specific frequency, and the liquid in the main chamber 60 is caused to resonate. As a result, low dynamic spring characteristics can be formed with respect to vibrations in a high frequency range targeted for muffled sounds, and as a result, the high frequency vibrations such as muffled sounds exhibit their vibration blocking function. Will be able to do it.

However, this conventional device cannot exhibit sufficient damping characteristics with respect to low-frequency vibrations, particularly vibrations for engine shakes.
That is, in FIG. 4, when low frequency vibration such as engine shake is propagated into the liquid chamber, the main chamber 60
The internal liquid is caused to flow through the orifice 20 into the sub-chamber 70 so that high damping characteristics can be obtained based on the flow resistance of the liquid in this flow action. However, in the above-described conventional apparatus, in this case, the bobbin 1 in the vibrator 10 is caused by the vibration of the liquid in the main chamber 60.
50 also vibrates, and there is a problem that the hydraulic pressure in the main chamber 60 does not rise sufficiently. As a result, the liquid that should have flowed into the sub chamber 70 via the orifice 20 accumulates in the main chamber 60, and does not flow sufficiently through the orifice 20. For this reason, there is a disadvantage that a sufficient attenuation coefficient (high attenuation characteristic) cannot be obtained. A liquid-filled type vibration damping device that has a vibration blocking effect against both low-frequency vibrations such as engine shakes and high-frequency vibrations such as muffled sounds. It is an object (problem) of the present invention to provide.

[0006]

Means for Solving the Problems In order to solve the above problems, the present invention takes the following measures. That is, a connection fitting attached to the vibrating body side, a holder attached to a member or the like on the vehicle body side, an insulator between the connection fitting and the holder for blocking vibration from the vibrating body, and an insulator connected in series to the insulator. A main chamber and a sub-chamber in which liquid is sealed, an orifice for communicating between the main chamber and the sub-chamber, a partition plate for separating the main chamber and the sub-chamber, An air chamber into which air as a fluid is introduced, a diaphragm separating the air chamber and the sub-chamber, and a diaphragm provided on a partition plate facing the main chamber, wherein the liquid in the main chamber is provided. And a vibrator that vibrates so as to resonate the liquid at a specific frequency with respect to a liquid-filled type vibration damping device that vibrates the vibrating coil constituting the vibrator so as not to vibrate under certain conditions. The Pasutoppa, Rutotomoni provided on the side facing to the main chamber of the transducer, the engine shea
When the vibration input related to the
And press the vibrator against the upper stopper
It was decided to adopt the configuration that was adopted.

[0007]

According to the present invention, the following effects are exhibited in the present invention. That is, in FIG. 1, the vibration from the vibrating body side (not shown) is transmitted to the insulator 5 made of a rubber material or the like via the connection fitting 91. Accordingly, the insulator 5 vibrates or displaces, and absorbs or blocks most of the input vibration. Therefore, most of the vibrations are cut off by the insulator 5, but some of them are
There is a case where the light is not absorbed by the insulator 5 but propagated to the vehicle body via the holder 95 and the like. Therefore, in the present invention, the vibration of the component (frequency) that could not be absorbed by the insulator 5 is transferred to the main chamber 6 and the sub-chamber 7 provided below the insulator 5.
And the like, and by the action of the vibrator 1 and the like provided in the main chamber 6 to absorb or cut off. Hereinafter, the specific operation will be described.

First, the interruption of the muffled sound caused by relatively high frequency vibration will be described with reference to FIG.
In this case, the target frequency (frequency) is 100 Hz.
It is a relatively high frequency range of about 300 Hz to about 300 Hz. Therefore, in this case, an alternating current of a predetermined frequency is applied to the excitation coil 11 of the vibrator 1 attached to the partition plate 3 via the yoke 16, and the excitation coil 11 and the bobbin 15 in which the excitation coil 11 is stored Is vibrated with respect to the permanent magnet 17.
The vibration of the bobbin 15 and the vibration coil 11 vibrates the incompressible fluid (liquid) in the main chamber 6. As a result, the liquid vibrates. If the state of the vibration at this time, particularly the phase thereof, matches the vibration propagated through the insulator 5, the liquid will cause liquid resonance. As a result, the dynamic spring constant formed by the action of the insulator 5 and the liquid resonance phenomenon in the main chamber 6 is set to a low value. That is, a low dynamic spring constant is formed, whereby relatively high-frequency vibrations that cause the muffled sound are cut off by the vibration isolator.

Next, a description will be given, with reference to FIG. 1 and FIG. 2, of vibration isolation for engine shake, which is low-frequency vibration. The target frequency (frequency) in this case is 10H
z. Accordingly, it is structurally difficult to reduce the dynamic spring constant of an anti-vibration device such as an engine mount to such an extent that it can resonate with vibration of this frequency. Therefore, in general engine mounts and the like, in order to cut off the vibration related to the engine shake, the vibration is suppressed by increasing the damping coefficient, whereby the vibration is cut off or the vibration is prevented. For this purpose, the main chamber 6
It must be possible for the liquid inside to flow sufficiently to the sub-chamber 7 through the orifice 2. This orifice 2
This is because a high damping characteristic can be obtained by the flow action of the liquid in the inside.

For this purpose, it is necessary that the hydraulic pressure in the main chamber 6 be sufficiently increased with respect to the propagation of vibration relating to the engine shake into the main chamber 6 through the insulator 5. Therefore, in this case, in the present invention, as shown in FIG. 2, a DC current is applied to the excitation coil 11 and the excitation coil 11 and the accommodation of the excitation coil 11 are stored based on the magnetic force between the excitation coil 11 and the permanent magnet 17. Bobbin 15
Of the bobbin 15
Is not moved (displaced) in the main chamber 6. Thus, even if low-frequency vibrations related to the engine shake and the like are propagated into the main chamber 6 via the insulator 5, the upper end surface 151 of the bobbin 15 forming the lower surface of the main chamber 6 does not move. , So that the volume in the main chamber 6 does not increase. As a result, the liquid pressure in the main chamber 6 increases, and the liquid in the main chamber 6 flows toward the sub chamber 7 via the orifice 2. As a result, a high damping characteristic (high damping coefficient) is obtained, and low-frequency vibration such as engine shake is suppressed. That is, the engine shake is cut off.

As described above, with respect to the vibration in the high frequency range, the vibration in the vibrator 1 causes the liquid in the main chamber 6 to resonate with the liquid, thereby forming a low dynamic spring characteristic. With respect to the vibration of (1), the vibrator 1 is fixed and the liquid pressure in the main chamber 6 is increased, so that the liquid flows sufficiently in the orifice 2 so that high damping characteristics can be obtained. I have. Thus, the low dynamic spring characteristic and the high damping characteristic can be obtained, and thereby, the muffled noise and the engine shake can be cut off.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the structure of the present embodiment includes a connecting member 91 connected to a vibrating body such as an engine, a holder 95 connected to a member or the like on the vehicle body side, and a space between the connecting member 91 and the holder 95. An insulator 5 for blocking vibration of large displacement (large amplitude) from the vibrating body;
Provided in series with the insulator 5;
A main chamber 6 and a sub-chamber 7 in which an incompressible fluid is sealed, an orifice 2 for communicating between the main chamber 6 and the sub-chamber 7, and a partition plate for partitioning the main chamber 6 and the sub-chamber 7 3, a vibrator 1 provided on the partition plate 3 on the side facing the main chamber 6, and an air chamber 8 into which a compressive fluid such as air is introduced.
It is basically composed of the diaphragm 4 for partitioning between the air chamber 8 and the sub-chamber 7.

In such a basic configuration, the vibrator 1 mounted on the partition plate 3 is installed on the yoke 16 fixed on the lower partition plate 32, as shown in FIG. An exciting coil (circularly formed around the permanent magnet 17 and the center pole 13 provided on the permanent magnet 17 and installed so as to be capable of relative displacement between the center pole 13 and the center coil 13 ( A voice coil) 11, a bobbin 15 that houses the vibration coil 11 and vibrates integrally with the vibration coil 11, and a rubber material that supports the bobbin 15 on a partition plate (upper partition plate 31). And a bobbin holder 14 and an upper stopper 12 provided above the bobbin 15 (inside the main chamber 6). The permanent magnet 17 is fixed on the lower partition plate 32 via the yoke 16, and the excitation coil 11 and the like are mounted on the upper partition plate 31 via the bobbin holder 14. The partition plate 3 is formed by integrating the partition plate 32 with a screw or the like. Further, the device assembled in this manner is used as the vibrator 1 in the main chamber 6.
It is configured to be installed inside.

In this configuration, the bobbin holder 1 supporting the bobbin 15 on the upper partition plate 31 is provided.
Reference numeral 4 denotes an elastic body such as a rubber material. In this embodiment, a member having a soft spring constant is used. This is because by making the spring constant soft, the value of the current applied to the exciting coil 11 can be reduced, and the exciting coil 11 can be vibrated with a small force. Instead, the excitation coil 11 and the bobbin 1
The upper stopper 12 is provided so that 5 and the like do not easily move (displace). As shown in FIGS. 2 and 3, the upper stopper 12 basically has a cup-like shape, and the vertical wall portion is configured to be fixed to the upper partition plate 31. . A portion corresponding to the bottom surface is provided with a plurality of flow ports 121 each having a small hole as shown in FIG. 3, and this portion is located above the upper end surface 151 of the bobbin 15 as shown in FIG. It is installed to come to the main room 6). Therefore, when the vibrating coil 11 of the vibrator 1 is vibrating, the liquid in the main chamber 6 flows through the flow port 121 and causes liquid vibration with the vibration of the upper end surface 151 of the bobbin 15. I have.

In the vibrator 1 having the above configuration, the center pole 13 made of a magnetic material such as electromagnetic soft iron is fixed to the yoke 16 via the permanent magnet 17, and the yoke 16 is installed on the lower partition plate 32. The excitation coil (voice coil) 11 is housed in a bobbin 15 and the bobbin 15 is connected to the upper partition plate 3 via a bobbin holder 14 made of rubber or the like.
1. And
The permanent magnet 17, the center pole 13, and the excitation coil 15 are adapted to perform a relative displacement (vibration) by passing an alternating current through the excitation coil 15. 15 has a configuration in which a lead wire 18 for flowing current is connected.

An operation mode of the embodiment having the above-described configuration will be described. First, interruption of a muffled sound caused by relatively high frequency vibration will be described with reference to FIG. In this case, the target frequency (frequency) is 100H
This is a relatively high frequency range of about z to 300 Hz. Therefore, in this case, an alternating current of a predetermined frequency is applied to the excitation coil 11 of the vibrator 1 attached to the partition plate 3 so that the excitation coil 1
1 and the bobbin 15 in which the exciting coil 11 is stored
Vibrates. Thus, the bobbin 15 and the vibration coil 11 vibrate the incompressible fluid (liquid) in the main chamber 6.
As a result, the liquid vibrates. If the state of the vibration at this time, particularly the phase thereof, matches the vibration propagated through the insulator 5, the liquid will cause liquid resonance. As a result, the dynamic spring constant formed by the action of the insulator 5 and the resonance phenomenon of the liquid in the main chamber 6 is set to a low value. In other words, a low dynamic spring constant is formed, whereby relatively high-frequency vibrations that cause booming noises are cut off by the vibration isolator.

Next, a description will be given, with reference to FIG. 1 and FIG. 2, of a method of blocking vibration of an engine shake which is low-frequency vibration. The target frequency (frequency) in this case is 10H
z. Therefore, it is structurally difficult to reduce the dynamic spring constant of an anti-vibration device such as an engine mount to such an extent that it can resonate with vibration of this frequency. Therefore, in general engine mounts and the like, in order to cut off the vibration related to the engine shake, the vibration is suppressed by increasing the damping coefficient, whereby the vibration is cut off or the vibration is prevented. For this purpose, the main chamber 6
It must be possible for the liquid inside to flow sufficiently to the sub-chamber 7 through the orifice 2. This orifice 2
This is because a high damping characteristic can be obtained by the flow action of the liquid in the inside.

For this purpose, it is necessary that the hydraulic pressure in the main chamber 6 be sufficiently increased with respect to the propagation of the vibration relating to the engine shake into the main chamber 6 via the insulator 5. Therefore, in this case, in this embodiment, as shown in FIG. 2, a DC current is applied to the exciting coil 11, and the exciting coil 11 and the housing of the exciting coil 11 are stored based on the magnetic force between the exciting coil 11 and the permanent magnet 17. Bobbin 15
Is pressed against the upper stopper 12 so that the upper end surface 151 of the bobbin 15 does not move in the main chamber 6. Accordingly, when low-frequency vibrations related to the engine shake and the like are propagated into the main chamber 6 via the isulator 5, the bobbin 15 forming a lower surface of the main chamber 6 is formed.
Is fixed so as not to move, so that the volume in the main chamber 6 does not increase. As a result, the liquid pressure in the main chamber 6 increases, and the liquid in the main chamber 6 flows toward the sub chamber 7 via the orifice 2. As a result, a high damping characteristic (high damping coefficient) is obtained, and low-frequency vibration such as engine shake is suppressed.
That is, the engine shake is cut off.

As described above, with respect to the vibration in a relatively high frequency range, the vibration in the vibrator 1 causes the liquid in the main chamber 6 to resonate with the liquid, thereby forming a low dynamic spring characteristic and a low dynamic spring characteristic. With respect to the vibration in the frequency range, the vibrator 1 is fixed and the liquid pressure in the main chamber 6 is increased, so that the liquid sufficiently flows through the orifice 2 so that high damping characteristics can be obtained. ing. As described above, the low dynamic spring characteristic and the high damping characteristic can be obtained, thereby shutting off the muffled sound and the engine shake.

[0020]

According to the present invention, there is provided a connecting member mounted on the vibrating body, a holder mounted on a member or the like on the vehicle body side, and a vibration interposed between the connecting metal and the holder. An insulator, a main chamber and a sub-chamber provided in series with the insulator and filled with an incompressible fluid (liquid); an orifice for communicating between the main chamber and the sub-chamber; A partition plate for partitioning between the chamber and the sub-chamber, an air chamber for introducing air or the like as a compressible fluid, a diaphragm for partitioning between the air chamber and the sub-chamber, and a side facing the main chamber. A vibrator that is provided on the partition plate and vibrates so as to cause the liquid in the main chamber to resonate at a specific frequency. Excitation coil Since the upper stopper that controls vibration so as not to vibrate below is provided on the side of the vibrator facing the main chamber, a noise caused by relatively high-frequency vibration is prevented. The vibrator is vibrated at a specific frequency, thereby causing the liquid in the main chamber to resonate with the liquid to form a low dynamic spring characteristic (low dynamic spring constant). The vibrator is fixed so that the liquid pressure in the main chamber is increased, so that the liquid in the main chamber flows in the orifice, so that a high damping characteristic (high damping coefficient) can be formed. became. The formation of such a low dynamic spring characteristic can cut off the muffled noise, and the formation of the high damping characteristic can also cut off the engine shake.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a liquid-filled type vibration damping device showing an entire configuration of the present invention.

FIG. 2 is a longitudinal sectional view of a vibrator constituting a main part of the present invention.

FIG. 3 is a plan view showing a configuration of an upper stopper which is a component of the vibrator according to the present invention.

FIG. 4 is a longitudinal sectional view showing the entire configuration of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vibrator 11 Vibration coil (voice coil) 12 Upper stopper 121 Distribution port 13 Center pole 14 Bobbin holder 15 Bobbin 151 Upper end face 16 Yoke 17 Permanent magnet 18 Lead wire 2 Orifice 3 Partition plate 31 Upper partition plate 32 Lower partition plate 4 Diaphragm Reference Signs List 5 insulator 6 main chamber 7 sub chamber 8 air chamber 91 connecting fitting 95 holder

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-42228 (JP, A) JP-A-6-346942 (JP, A) JP-A-5-272574 (JP, A) JP-A-7- 139579 (JP, A) JP-A-3-885736 (JP, U) JP-A-4-39481 (JP, Y2) US Patent No. 4756513 (US, A) (58) Fields investigated (Int. Cl. ⁷ , DB) Name) F16F 13/26 B60K 5/12

Claims (1)

(57) [Claims] 1. A connecting member attached to a vibrating body, a holder attached to a member or the like on a vehicle body, an insulator interposed between the connecting member and the holder, for isolating vibration from the vibrating body, and an insulator for the insulator. A main chamber and a sub-chamber provided in series with each other and filled with a liquid, an orifice communicating between the main chamber and the sub-chamber, and a partition plate separating the main chamber and the sub-chamber. An air chamber into which air as a compressible fluid is introduced, a diaphragm for partitioning the air chamber from the sub chamber, and a diaphragm provided on a partition plate facing the main chamber. In a liquid-filled type vibration damping device including a vibrator that vibrates the liquid in a room so as to resonate at a specific frequency, the vibration coil constituting the vibrator is controlled so as not to vibrate under a certain condition. Shake An upper stopper is provided on the side of the vibrator facing the main chamber, and an engine shaft is provided.
When the vibration coil is energized,
So that the vibrator is pressed against the upper stopper
A liquid-filled type vibration damping device characterized by having the following configuration.