JP5289167B2 - Vibration isolator - Google Patents

Description

  The present invention relates to a vibration isolator capable of exhibiting an excellent vibration damping function and vibration insulation function regardless of the vibration frequency generated based on the flow of an incompressible liquid sealed therein. However, the present invention relates to a vibration-proof vibration device. For example, it can be used as an engine mount to effectively attenuate and absorb each of idling vibration and engine shake vibration, and becomes high-frequency small-amplitude vibration of 50 to 150 Hz. The present invention proposes a technique for effectively suppressing and attenuating an increase in dynamic spring constant (higher dynamic spring) with respect to vibrations in the vehicle interior booming noise, lock-up vibration, and the like by high frequency liquid column resonance.

  As a conventional anti-vibration device containing liquid that is applied as an engine mount and switches a flow path of a sealed liquid under the action of a negative pressure actuator, there is one disclosed in Patent Document 1.

  This is an anti-vibration device of liquid type that contains negative pressure, etc., `` A part of the wall is made of a rubber elastic body, and a pressure receiving chamber into which vibration is input and a working air chamber are formed behind it. In an active fluid-filled vibration isolator in which a part of the wall is composed of a vibration rubber plate and pressure fluctuations are caused to communicate with each other through an orifice passage, the vibration chamber extends over the working air chamber. In order to reduce the transmission of a high-frequency component of the vibration frequency to be vibrated in the air pressure fluctuation to be received to the pressure receiving chamber, the above-mentioned “vibration volume based on the orifice passage: V and air pressure fluctuation exerted on the working air chamber” Considering the unit flow rate: Q of the fluid that is allowed to flow through the orifice passage in accordance with the vibration displacement of the rubber plate, the ratio thereof: the value of V / Q is 1 or more and 10 or less. It is.

In this device, for example, when the medium frequency orifice passage is opened when the vehicle is stopped, and the internal pressure fluctuation is caused in the pressure receiving chamber by the medium frequency vibration such as idling vibration, the pressure receiving chamber and the equilibrium chamber Based on the relative internal pressure difference between the two chambers, a fluid flow is generated between the two chambers through the medium frequency orifice passage. Based on the resonance action of the fluid, the fluid is passive to idling vibration. It is assumed that the anti-vibration effect can be exhibited.
On the other hand, when the vehicle is traveling, the orifice passage for medium frequency is shut off, and the pressure control valve is controlled to be switched at a cycle and phase corresponding to high-frequency vibrations such as traveling booming noise to be isolated.
As a result, when an internal pressure fluctuation is induced in the pressure receiving chamber due to low frequency vibration such as engine shake, the low frequency orifice is set between the two chambers based on the relative internal pressure difference between the pressure receiving chamber and the equilibrium chamber. It is assumed that fluid flow through the passage is generated, and that a passive vibration-proofing effect against engine shake or the like can be exhibited based on the resonance action of the fluid.

  Further, the working air chamber is alternately switched and connected to the atmosphere and the negative pressure source based on the switching control of the pressure control valve, so that the working air chamber is subjected to air pressure fluctuations in a cycle corresponding to a traveling boom sound or the like. Thus, the vibration rubber plate is driven to vibrate, and the internal pressure fluctuation generated in the vibration chamber is applied to the pressure receiving chamber through the high-frequency orifice passage, thereby being based on the positive pressure control of the pressure receiving chamber. It is assumed that an active vibration-proofing effect can be effectively exerted against running-over noise, etc., and as a result, low-frequency vibration such as engine shake, medium-frequency vibration such as idling vibration, and high-frequency vibration such as running-over noise. On the other hand, both of them can obtain an effective anti-vibration effect, and are different from each other such as low-frequency engine shake and high-frequency traveling noise when the vehicle is traveling. That with respect to the vibration of the frequency range, and it is possible to exert a vibration damping effect at the same time.

JP 2003-130124 A

  However, in this prior art, in order to prevent the high-frequency passenger compartment vibrations from being vibrated by the vibration drive of the vibration rubber plate, the negative pressure is reduced into the working air chamber based on the switching control of the pressure control valve. Since it is necessary to introduce pressure alternately corresponding to the target vibration cycle, the structure of the vibration isolator is complicated, and the size of the device is inevitably increased. There is a problem that it is necessary to control the pressure of the working air chamber in order to drive the vibration rubber plate.

  The object of the present invention is to solve such problems of the prior art, and the object of the present invention is to make the structure of the apparatus complicated, increase the size of the apparatus, etc. In addition, the vibration drive control of the vibration rubber plate is not required, and the increase in the dynamic spring constant with respect to the high-frequency cabin boom noise vibration, lock-up vibration, etc. of 50 to 150 Hz is effectively suppressed. An object of the present invention is to provide an anti-vibration device that can effectively dampen vibrations.

The vibration isolator of the present invention includes a core member connected to one side of a vibration generation side member or a vibration transmission side member and a cylindrical member around the core member connected to the other side. The outer peripheral surface of the core member and the inner peripheral surface of one end portion of the cylindrical member can be made of rubber, elastomer, etc., and the side surface contour shape has a truncated cone shape such as a truncated cone and a truncated pyramid. A cylindrical member that is liquid-tightly connected to the entire circumference by an elastic member and that the other end of the cylindrical member is liquid-tightly sealed by a diaphragm, and a lining layer may be formed by the elastic member. Inside, at least the space between the diaphragm and the elastic member, sometimes in addition to the core member that may be exposed from the elastic member, is made into incompressible water, alkylene glycol, polyalkylene. The fluid chamber is filled with a liquid such as glycol or silicone oil, and the fluid chamber is divided into a main liquid chamber located on the elastic member side and a sub liquid chamber located on the diaphragm side, with a partition member. Both of these liquid chambers are independent of each other in a first restriction passage that provides damping of idling vibration of 20 to 40 Hz and a second restriction passage that provides attenuation of engine shake vibration of 5 to 20 Hz. A negative pressure actuator that communicates and further displaces the diaphragm outside the diaphragm at the other end of the cylindrical member between a position at which the opening of the first restriction passage is closed and a position at which the opening is separated from the opening. The other end of the third restriction passage for high frequency vibration of 50 to 150 Hz provided at one end in communication with the main liquid chamber is connected to the cylinder. Sealing an opening bored in the peripheral wall of the member in a liquid-tight manner, one side is closed by an elastic membrane member facing directly or indirectly the air, the elastic membrane member, the elastic member is a separate body, The opening of the cylindrical member is formed of rubber that seals liquid-tightly from the outer surface side of the cylindrical member .

  Further, here, when the negative pressure actuator is provided with a rigid flat portion that presses and supports the diaphragm at a position where the opening of the first restriction passage is closed, the main liquid chamber is caused by the unintentional escape deformation of the diaphragm. It is preferable for preventing an unintended decrease in pressure.

  In this case, preferably, each of the airtight chamber portion of the negative pressure actuator and the pressing support portion of the diaphragm to the opening of the first restriction passage is constituted by a rigid member integrated with each other, and the integral portion thereof. A flexible membrane body is provided that hermetically connects the periphery of the forming portion to the housing.

  In addition, it is preferable that spring means for constantly generating a pressing force in a direction in which the diaphragm closes the opening of the first restriction passage is disposed in the negative pressure actuator, and the diaphragm is formed integrally with the negative pressure actuator. It is preferable to do.

  In the vibration isolator of the present invention, it is applied as an engine mount. For example, in a state where the core member is connected to the engine side member and the cylindrical member is connected to the vehicle body side member, For input of idling vibration (medium frequency (20 to 40 Hz), medium amplitude (0.05 to 0.2 mm) vibration), the negative pressure actuator is operated to move the diaphragm from the opening end of the first restriction passage. Separating the respective liquids in the main liquid chamber and the sub-liquid chamber through the first restricting passage under the free deformation of the diaphragm, so that at the tuning frequency of the first restricting passage, Based on the liquid column resonance, flow resistance, etc. of the liquid in the passage, idling vibration can be effectively damped, and the resonance frequency and its adjacent frequencies are effectively low. It can be spring of.

On the other hand, atmospheric pressure is introduced into the negative pressure actuator for the input of 5 to 20 Hz engine shake vibration (vibration with low frequency and large amplitude (0.5 to 1 mm)) during vehicle travel. Thus, under the action of the built-in spring means in the negative pressure actuator, the diaphragm is pressed around the opening of the first restriction passage with the pressing support portion of the negative pressure actuator to completely close the opening. By preventing the flow of liquid through the restricting passage and allowing the liquid in both chambers to flow through the second restricting passage, also under free deformation of the outer portion of the diaphragm actuator area, Based on the liquid column resonance of the liquid in the passage at the tuning frequency of the second restricted passage, the engine shake vibration can be effectively damped and the dynamic spring can be reduced. Kill.
The second restriction passage is in a so-called clogged state with respect to vibrations having a higher frequency (20 to 40 Hz) such as idling vibrations, and allows the flow of liquid in each liquid chamber. It will be in an unobtainable state.

In addition, in this vibration isolator, the second restriction passage is clogged, and a high frequency (50 to 150 Hz) small amplitude vibration input such as a cabin booming vibration during driving of the vehicle or a vibration during lockup is provided. On the other hand, with the diaphragm, the liquid in the main liquid chamber, which has entered the third restriction passage under the state where the opening of the first restriction passage is closed in the same manner as described above, is transferred to the elastic film body. By resonating in the liquid under a preselected spring characteristic, it is possible to effectively dampen the cabin sound and vibration during lockup, and to reduce the dynamic spring.
Here, in tuning the resonance frequency of the liquid in the third restriction passage, the elasticity of the elastic member can be increased by reducing the size of the opening of the cylindrical member or increasing the thickness of the elastic film body. By setting the film body to have a harder spring characteristic, the liquid column resonance frequency can be shifted to the high frequency side as required, so that the liquid in the third restricting passage has its resonance frequency. In addition, it is possible to suppress an increase in the dynamic spring constant in the vicinity thereof and to effectively attenuate high-frequency small-amplitude vibration.

  Here, when the elastic film body is formed of the same kind of rubber as the elastic member, which is continuous with the elastic member, for example, an unvulcanized rubber with respect to the core member and the cylindrical member in the injection mold. Injecting a single type of raw rubber, it is possible to construct the required integral molded body by injection of a single type of raw rubber. Therefore, a required integral molded body can be efficiently manufactured.

  On the other hand, when the elastic film body is formed of rubber that is separated from the elastic member and seals the opening of the cylindrical member liquid-tightly from the outer surface side of the cylindrical member, the elastic film body The resonance frequency of the liquid in the third restriction passage can be easily set as expected by appropriately selecting the spring characteristics and the like of the first member as required regardless of the physical properties of the elastic member. .

  Here, when the negative pressure actuator is provided with a rigid flat portion that presses the diaphragm to a position for closing the opening of the first restriction passage, the direction of the diaphragm portion in the state in which the opening is closed escapes from the opening. Can be sufficiently prevented by the rigid flat portion of the negative pressure actuator, so that the main liquid chamber pressure is prevented from being consumed to deform the diaphragm, and the liquid in the main liquid chamber It is possible to efficiently and smoothly flow through the restriction passage and the like, and to exhibit the vibration damping function and the low dynamic spring function as expected.

  Then, each of the airtight chamber portion of the negative pressure actuator and the pressing support portion of the diaphragm to the opening of the first restriction passage is constituted by a rigid member integrated with each other, and the integrated portion thereof When the flexible film body that hermetically connects the periphery of the housing to the housing is provided, the integrated part of the negative pressure actuator is displaced quickly and smoothly as expected under the deformation of the flexible film body. be able to.

  In addition, when a spring means is provided in the negative pressure actuator that constantly generates a pressing force in such a direction that the diaphragm closes the opening of the first restriction passage, the negative pressure actuator having a simple and simple structure can be used. The expected operation, in particular, the opening and closing operation of the first restricting passage, can always be performed reliably and quickly simultaneously with the introduction of the atmospheric pressure into the negative pressure actuator.

  Furthermore, when the diaphragm and the negative pressure actuator are integrally formed, the deformation and displacement of the diaphragm can be interlocked with the operation of the airtight chamber portion and the diaphragm pressing support portion as the operation portion of the negative pressure actuator. The diaphragm can always be surely closed and separated from the opening of the first restricting passage, and at the same time, both postures can be constant as expected.

It is a longitudinal section showing a central axis showing one embodiment of this invention. It is a longitudinal cross-sectional view which shows the apparatus shown in FIG. 1 by damping postures, such as an engine shake vibration and a vehicle interior sounding vibration. It is a graph which illustrates typically the reduction characteristic of engine shake vibration, and low dynamic springs with booming sound vibration. It is a longitudinal cross-sectional view similar to FIG. 1 which shows other embodiment. It is a longitudinal cross-sectional view which shows the modification of a vibration isolator.

  In the first embodiment of the vibration isolator of the present invention, as shown in FIG. 1, a core member 1 connected to either one of a vibration generating side member of an engine and other members or a vibration transmitting side member of an automobile body or the like. In addition, each of the cylindrical members 2 is arranged around the core member 1 so as to be aligned with the axis and connected to the other side, and the outer peripheral surface of the core member 1 and one of the cylindrical members 2 are provided. The inner peripheral surface of the end portion, in the figure, an inverted frustoconical shape or an inner peripheral surface having an inverted truncated pyramid shape is liquid-tightly connected over the entire circumference by an elastic member 3 made of rubber, elastomer, plastic, etc. The other end of the cylindrical member 2 is liquid-tightly sealed with a diaphragm 4.

  In the figure, the lining layer 3a made of the elastic member 3 is formed up to the lower end flange portion of the equal-diameter portion 2a of the cylindrical member 2, but the lining layer 3a made of the elastic member 3 is essential. It's not something.

  And here, inside the tubular member 2, more precisely, inside the lining layer 3a on the inner surface of the tubular member 2, at least a space sandwiched between the diaphragm and the body portion 3b of the elastic member 3, sometimes In addition to this, a space sandwiched between the core member 1 that may be exposed from the main body portion 3b of the elastic member 3 is defined as a fluid chamber 5 in which a required incompressible liquid is enclosed, and the fluid chamber 5 Is divided into a main liquid chamber 7 located on the basic portion 3b side of the elastic member 3 and a sub liquid chamber 8 located on the diaphragm 4 side by a partition member 6 that can be made of a rigid material such as metal or hard plastic. In addition to partitioning, both the liquid chambers 7 and 8 are provided in the partition member 6 in the figure, and a first restriction passage 9 for damping idle vibration and damping of engine shake vibration are provided. In general, the second restriction passages 10 having a smaller cross-sectional area and a longer length than the restriction passage 9 are communicated independently of each other.

  Here, the second restriction passage 10 opens to the main liquid chamber 7 through a wall through hole (not shown) provided at one end, and enters the sub liquid chamber 8 through a wall through hole (not shown) provided at the other end. Open.

  In addition, here, the housing 11 that is positioned outside the diaphragm 4 is attached to the other end side of the cylindrical member 2 by caulking, fixing, or the like, and the diaphragm 4 is placed in the housing 11 in the first restriction passage 9. The negative pressure actuator 12 that is displaced and deformed between a position where the opening on the side of the auxiliary liquid chamber 8 is closed and a position separated from the opening as shown in the figure is housed.

1 and 2, the partition wall 10 a of the restriction passage 10 provided in the partition member 6 and the diaphragm 4 are vulcanized and bonded to the lower end portion of the equal-diameter portion 2 a of the cylindrical member 2. Each of the annular member 4a and the upper end portion 11a of the negative pressure actuator housing 11 is caulked and fixed integrally, but this is not an essential configuration for the present invention.
Here, the airtight chamber portion 13a of the negative pressure actuator 12 and the pressure support portion 13b made of a rigid flat portion that presses and supports the diaphragm 4 at a position where the opening of the first restricting passage 9 is closed are both made of a rigid material. The flexible film body 14 that can be an elastic film body that is airtightly connected to the periphery of the integrated product 13 is also connected to the outer periphery of the flexible film body 14 via a rigid cylinder 15 that is airtightly connected by vulcanization adhesion or the like. In addition, although it is caulked and fixed to the lower end portion of the equal-diameter portion 2a of the cylindrical member 2, this is not an essential configuration for the present invention.

Here, the space defined between the diaphragm 4 and the negative pressure actuator 12 may be communicated with the atmosphere so as to ensure free and smooth displacement and deformation of the diaphragm 4 and the flexible film body 14. preferable.
Further, the negative pressure actuator 12 connects the negative pressure chamber 16 therein to a negative pressure supply source (not shown) via a valve 17, and the negative pressure chamber 16 includes a bottom of the housing 11. A spring means 18, which can be a coil spring, for example, is disposed on each of the wall 13, the integrated part 13 of the airtight part 13 a and the pressing support part 13 b of the diaphragm 4, especially the pressing support part 13 b.
The spring means 18 functioning as a return spring when the atmospheric pressure is introduced into the negative pressure chamber 16 always generates a pressing force in a direction in which the diaphragm 4 closes the opening of the first restriction passage 9.

As described above, the pressing support portion 13b having the flat portion for pressing and supporting the diaphragm 4 of the negative pressure actuator 12 at the position where the opening of the first restriction passage 9 is closed is, as described above, the rigid member. It is preferable that the pressure support portion 13b and the hermetic chamber portion 13a are made of a rigid member integrated with each other, and the integrated product 13 is formed as shown in FIG. The flexible film body 14 for airtightly connecting to the housing 11 is airtightly connected to the peripheral surface of the integrated body 13 by vulcanization adhesion or the like.
The outer peripheral surface of the flexible film body 14a is vulcanized and bonded to the inner peripheral surface of the rigid cylinder 15 in an airtight manner as described above.
By the way, as shown in FIGS. 1 and 2, the airtight chamber portion 13a and the pressing support portion 13b can be integrated with each other, as shown in FIGS. The case where the portions 13a and 13b are integrated by fixing, adhering or the like afterwards at a required timing is also included.

  In addition, in this apparatus, in addition to the two restriction passages 9 and 10 described above, the partition member 6 has one end opened to the main liquid chamber 7 and the other end in the equal-diameter portion 2a of the cylindrical member 2. A third restriction passage 19 is formed on the peripheral surface of the third restriction passage 19 that is continuous with the elastic member 3 and ends with a lining layer 3a made of the same kind of rubber as the elastic member 3, that is, the other end is closed with the lining layer 3a. 1 and 2 are formed in a bowl shape.

  Function to suppress increase in dynamic spring constant and to attenuate vibration against vibration input such as cabin noise and lockup vibration, which becomes small amplitude vibration in the high frequency range of 50 to 150 Hz. The lining layer portion that seals the other end of the third restriction passage 19 in a liquid-tight manner seals the opening 20 that is drilled through the equal-diameter portion 2a of the tubular member 2 in a fluid-tight manner. The outer surface functions as an elastic film body 21 facing the atmosphere, and the spring characteristics of the elastic film body 21 are adjusted as required by selecting the size of the opening 20, the thickness of the elastic film body itself, the material, and the like. be able to.

  Incidentally, when the elastic film body 21 is given a hard spring characteristic by reducing the size of the opening 20 or by increasing the thickness of the elastic film body 21, the liquid that has entered the third restriction passage 19 The liquid column resonance frequency can be shifted to the high frequency side, thereby effectively suppressing an increase in the dynamic spring constant and exhibiting a vibration damping function with respect to the resonance frequency and vibrations in the vicinity thereof. Can do.

  Therefore, as shown in FIGS. 1 and 2, the elastic film body 21 can have a thickness that does not enter the opening 20 at all, or the opening 20 is entirely or partially embedded, or The thickness can be adjusted to the outside of the opening 20.

  In the vibration isolator configured as described above, when it is applied as an engine mount, as described above, the negative pressure actuator 12 is applied to the input of idling vibration of medium frequency and medium amplitude when the vehicle is stopped. 1, the diaphragm 4 is separated from the opening of the first restricting passage 9 on the side of the auxiliary liquid chamber 8, and the main auxiliary liquid is deformed under the deformation of the elastic body portion 3 b and the diaphragm 4. By causing the liquid in the chambers 7 and 8 to flow into the first restricting passage 9 and causing the liquid in the passage 9 to resonate at the tuning frequency, the idling vibration is based on liquid column resonance, flow resistance, and the like. It can be effectively damped and an increase in the dynamic spring constant can be effectively suppressed.

  In this case, the second restricting passage 10 is substantially clogged by the liquid in the passage, and no liquid flows through the restricting passage 10, so that the main and sub liquid chambers 7, 8 An unintended drop in the pressure of the liquid inside is sufficiently prevented, and the intended vibration damping function and the like are exhibited.

On the other hand, for the low frequency large amplitude vibration input such as engine shake vibration when the vehicle is running, the atmospheric pressure is introduced into the negative pressure actuator 12 to cause the spring means 8 to act as shown in FIG. As shown in the drawing, the diaphragm 4 is brought into close contact with the opening of the first restricting passage 9 by the pressing support portion 13b of the integrated object 13, while the liquid in the main auxiliary liquid chambers 7 and 8 is allowed to flow inside the second restricting passage 10. , The engine shake vibration can be effectively damped and the spring can be lowered based on the liquid column resonance of the liquid in the passage 9 and the flow resistance received by the liquid from the passage 10.
By the way, with respect to this engine shake vibration, the opening of the first restricting passage 9 is completely closed by the diaphragm 4 backed up by the pressing support portion 13b made of a rigid flat portion, and the relative change in the pressure in the main and auxiliary liquid chambers. Since the unintentional deformation of the diaphragm accompanying this can be sufficiently prevented, it is possible to achieve more effective damping of vibration and further lower dynamic spring without loss of the main / sub-liquid chamber pressure.

Further, as shown in FIG. 2, the opening of the first restriction passage 9 is formed by a diaphragm 4 for high-frequency and small-amplitude vibration inputs such as a cabin boom noise and a lock-up vibration when the vehicle is running. Under the sealed condition, the liquid that has entered the third restriction passage 19 is caused to resonate with the liquid column based on the preselected spring characteristics of the elastic film body 21, thereby reducing the vibration and reducing the vibration. It can be made into a dynamic spring.
In this case, the opening of the first restriction passage 9 is closed by the diaphragm 4, and the second restriction passage 10 is clogged by the liquid in the passage. The unexpected drop in pressure is sufficiently prevented, and the vibration is attenuated and the dynamic spring is made sufficiently effective.

FIG. 3 is a graph schematically showing the damping characteristics of the engine shake vibration and the low dynamic spring of the booming sound vibration by the vibration isolator as described above, and the solid line in the figure tunes the resonance frequency to 10 Hz. In this figure, the engine shake vibration attenuation performance is shown. The broken line in the figure shows the dynamic spring constant of the booming sound vibration when the resonance frequency is tuned to 80 Hz.
Note that the dynamic spring constant of the vibration isolator without the third restriction passage and the elastic film body for the cabin sound is as shown by a two-dot chain line in FIG. , Peak high values will be shown.

  Therefore, according to the position shown in FIG. 3, it is possible to quickly attenuate the engine shake vibration of 10 Hz and its front and rear frequencies, and to effectively prevent transmission of the vibration to the vehicle body side. It can be seen that high-velocity springs can be prevented and vibration transmission to the vehicle body side can be effectively prevented with respect to booming noise vibrations of 80 Hz and around that frequency.

FIG. 4 is a longitudinal sectional view similar to FIG. 1 showing another embodiment. This is different from the elastic member 3 in that the elastic film body 21 that closes the other end of the third restriction passage 19 is closed. 1 and 2 in that the opening 20 formed in the equal-diameter portion 2a of the cylindrical member 2 is liquid-tightly sealed from the outer surface side of the cylindrical member 2. The thing is different in structure.
By the way, the elastic film body 21 does not enter the opening 20 at all, and can enter the opening 20 partially or entirely, and is provided corresponding to the opening 20. The lining layer 3a is inserted into the through-hole and is continuously continuous with the lining layer 3a, or the opening 20 is laminated and joined to the lining layer 3a that closes the inner surface of the cylindrical member 2 It is also possible.

FIG. 5 is a longitudinal sectional view showing a modification of the above-described vibration isolator, which closes the other end of the third restricting passage 19 without making an opening in the tubular member 2. Between the elastic film body 21 and the cylindrical member 2, in the drawing, between the elastic film body 21 and the lining layer 3 a to the cylindrical member 2, an airtight air chamber 22 positioned on the extension of the restriction passage 19 is provided. The configuration differs from that of the above-described apparatus in that it is partitioned.
In this vibration isolator, by adjusting the internal pressure of the airtight air chamber 22, spring characteristics having a required hardness can be imparted to the elastic film body 21.
Also with this illustrated apparatus, the same function as described above can be exhibited with respect to various vibration inputs.

  By the way, in the above-described vibration isolator, the diaphragm 4 is preferably formed integrally with the negative pressure actuator 12, and according to this, the deformation and displacement of the diaphragm 4 are interlocked with the operating portion of the negative pressure actuator 12. The opening of the restricting passage 9 of the diaphragm 4 and the separation from the opening are always ensured, and the closing and separating posture is constant as expected. be able to.

DESCRIPTION OF SYMBOLS 1 Core member 2 Cylindrical member 2a Equal-diameter part 3 Elastic member 3a Lining layer 3b Main body part 4 Diaphragm 4a Annular member 5 Fluid chamber 6 Partition member 7 Main liquid chamber 8 Sub liquid chamber 9 First restriction channel 10 Second restriction Passage 10a Partition wall 11 Negative pressure actuator housing 11a Upper end portion 12 Negative pressure actuator 13 Integrated object 13a Airtight chamber portion 13b Pressing support portion 14 Flexible film body 15 Rigid cylindrical body 16 Negative pressure chamber 17 Valve 18 Spring means 19 Third Restricted passage 20 Opening 21 Elastic membrane body

Claims (5)

A core member connected to either one of the vibration generation side member or the vibration transmission side member and a cylindrical member connected to the other side are provided, and the outer peripheral surface of the core member and one end of the cylindrical member are provided. The partial inner circumferential surface is liquid-tightly connected to the entire circumference by an elastic member, and the other end of the cylindrical member is liquid-tightly sealed by a diaphragm, and at least the diaphragm and the elastic member are disposed inside the cylindrical member. The space sandwiched between the two is a fluid chamber enclosing a liquid, and the fluid chamber is partitioned into a main liquid chamber located on the elastic member side and a sub liquid chamber located on the diaphragm side with a partition member. The two fluid chambers are communicated independently of each other in the first restricting passage that attenuates idling vibration and the second restricting passage that attenuates engine shake vibration. The other end, said diaphragm be one that a position to close the opening of the first restricting passage, formed by providing a negative pressure actuator for displacing over between a position away from the opening,
The other end of the third restriction passage provided with one end communicating with the main liquid chamber is liquid-tightly sealed with an opening formed in the peripheral wall of the cylindrical member, and one side is closed by an elastic film body facing the atmosphere. and,
An anti-vibration device in which the elastic film body is formed of rubber that is separated from the elastic member and seals the opening of the cylindrical member liquid-tightly from the outer surface side of the cylindrical member . The vibration isolator according to claim 1, wherein the negative pressure actuator is provided with a rigid flat portion that presses and supports the diaphragm at a position where the opening of the first restriction passage is closed. Each of the airtight chamber portion of the negative pressure actuator and the pressing support portion of the diaphragm to the opening of the first restriction passage is configured by a rigid member integrated with each other, and the integrated portion is formed in the housing. The vibration isolator according to claim 1 or 2 , further comprising a flexible film body connected in an airtight manner. The vibration isolator according to any one of claims 1 to 3 , wherein a spring means for constantly generating a pressing force in a direction in which the diaphragm closes the opening end of the first restriction passage is disposed in the negative pressure actuator. The vibration isolator according to any one of claims 1 to 4 , wherein the diaphragm and the negative pressure actuator are integrally formed.

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