JP2010203566A - Liquid sealing type vibration control device and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid sealing type vibration control device effectively absorbing vibrations of not only a low frequency area but also a middle frequency area, saving cost, and having high reliability. <P>SOLUTION: In the liquid sealing type vibration control device 1 wherein a first metallic member 2 and a second metallic member 4 are connected through an elastic member 7, a liquid chamber is constituted by a pressure receiving chamber 8, a first equilibrium chamber 9, and at least one second equilibrium chamber 10. The pressure receiving chamber 8 and the first equilibrium chamber 9 are separated from each other by a partitioning member 11, and communicated by a first orifice 12 which is a damping flow passage detouring the partitioning member 11. The pressure receiving chamber 8 and the second equilibrium chamber 10 are communicated by a second orifice 14, and the second equilibrium chamber 10 and the second orifice 14 are integrally molded by the elastic member 7. The maximum cross-sectional area (S<SB>1</SB>) in the second equilibrium chamber 10 is larger than the minimum cross-sectional area (S<SB>0</SB>) of the second orifice 14. A thin-wall portion 15 is provided on a part of a wall of the second equilibrium chamber 10, and the volume of the second equilibrium chamber 10 can be increased. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid-filled vibration isolator that can be used for an engine mount for automobiles and the like, and a manufacturing method thereof.

  2. Description of the Related Art Conventionally, a fluid-filled vibration isolator that obtains a vibration-proof effect based on a fluid action such as a resonance action of an incompressible fluid sealed inside has been used as an engine mount for automobiles. Specifically, it has a first metal member connected to one of the vibration source side or the support side and a second metal member connected to the other, and the first metal member and the second metal member are made of rubber. A liquid-filled vibration isolator in which a liquid chamber having the elastic member as a part of a wall is provided and the liquid chamber is sealed with an incompressible fluid. The liquid chamber is composed of a pressure receiving chamber and an equilibrium chamber, and the pressure receiving chamber and the equilibrium chamber are connected by an orifice that is a damping channel, and the volume of the equilibrium chamber can be increased as fluid flows into the equilibrium chamber. There is known a liquid-filled vibration isolator. (For example, patent document 1 etc.).

  In such a liquid-filled vibration isolator, vibration in a frequency region corresponding to the resonance frequency of the liquid flowing in the orifice can be efficiently absorbed. As shown in Patent Document 1, the orifice is normally configured as a damping flow path that bypasses a partition member that partitions the pressure receiving chamber and the equilibrium chamber. In this case, the resonance frequency is relatively small, and vibrations in the low frequency region can be absorbed efficiently. However, for example, when used as an engine mount for an automobile, vibrations in the middle frequency range of about 100 to 600 Hz are generated from the rotational speed of the engine and various members that are driven in association with the engine speed. The vibration in the region could not be absorbed efficiently with a simple structure.

  On the other hand, for example, in Patent Document 2, in a liquid-sealed mount, a medium-high-frequency component is formed by forming a flow space between a support member protruding into a main liquid chamber and a conical inner wall of an elastic member. A thin-walled portion is provided to provide a minimum value for dynamic spring characteristics by generating a membrane resonance at a portion of the conical portion of the elastic member by vibration input in the medium- and high-frequency region, with a medium-high-frequency device for absorbing Is described. According to the embodiment of Patent Document 2, the above-described medium / high frequency device has a substantially cup shape and is caulked and fixed to the support member. However, this increases the number of parts and the number of manufacturing processes, so an increase in cost is inevitable. Moreover, introducing caulking fixing parts in the vibration isolator may cause a problem in terms of reliability during long-term use. Furthermore, it is not always easy to adjust the anti-vibration performance corresponding to the product.

JP 2006-34295 A JP 10-339348 A

  The present invention has been made to solve the above problems, and provides a low-cost and highly reliable liquid-filled vibration isolator that effectively absorbs vibrations not only in the low frequency region but also in the middle frequency region. It is intended to provide. Moreover, it aims at providing the suitable manufacturing method of such a liquid enclosure type vibration isolator.

The above-described problem has a first metal member connected to one of the vibration source side or the support side and a second metal member connected to the other, and the first metal member and the second metal member are made of rubber. In the liquid-filled vibration isolator, which is connected via an elastic member and has a liquid chamber having the elastic member as a part of a wall, and the liquid chamber is sealed with an incompressible fluid, The chamber is composed of a pressure receiving chamber, a first equilibrium chamber, and at least one second equilibrium chamber. The pressure receiving chamber and the first equilibrium chamber are separated by a partition member, and the damping channel bypasses the partition member. And a part of the wall of the first equilibrium chamber constitutes a diaphragm, and the volume of the first equilibrium chamber can be increased as the fluid flows into the first equilibrium chamber. The pressure receiving chamber and the second equilibrium chamber communicate with each other through the second orifice, and the second equilibrium chamber and the second orifice Graphics and is integrally molded of an elastic member made of rubber, the maximum cross-sectional area of the second balancing chamber (S ₁₎ is greater than the minimum cross-sectional area of the second orifice (S _0), the wall of the second balancing chamber A liquid-filled vibration-proof type having a thin-walled portion in part and capable of increasing the volume of the second balanced chamber by deformation of the thin-walled portion as the fluid flows into the second balanced chamber It is solved by providing a device. At this time, the ratio (S ₁ / S ₀ ) of the maximum cross-sectional area (S ₁ ) in the second equilibrium chamber to the minimum cross-sectional area (S ₀ ) of the second orifice is preferably 1.2 to 3, It is also preferable that 2 to 8 equilibration chambers are provided.

  In addition, the above-described problem is that the first metal member and the second metal member are mounted in a mold, filled with unvulcanized rubber in the mold and vulcanized, and then the first metal member and the second metal In the vulcanization bonding of the member, there is a step of removing the convex portions of the mold corresponding to the second equilibrium chamber and the second orifice from the vulcanized rubber molded product after vulcanization. The problem can also be solved by providing a method of manufacturing a vibration device.

  According to the liquid-filled vibration isolator of the present invention, a low-cost and highly reliable liquid-filled vibration isolator that can effectively absorb not only the low-frequency region but also the medium-frequency region is provided. Further, according to the manufacturing method of the present invention, such a liquid-filled vibration isolator can be easily manufactured.

It is a side view of an example of the vibration isolator of this invention. It is a longitudinal cross-sectional view (shape Y) of an example of the vibration isolator of this invention. It is AA sectional drawing (shape Y) of an example of the vibration isolator of this invention. It is a BB cut surface (shape Y) of an example of the vibration isolator of the present invention. It is the elements on larger scale which showed the section shape when the shape of the 2nd orifice was changed. It is the graph which plotted the dynamic spring constant when the shape of a 2nd orifice was changed with respect to the frequency.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view of an example of a vibration isolator according to the present invention. FIG. 2 is a longitudinal sectional view (shape Y) of an example of the vibration isolator of the present invention. FIG. 3 is an AA sectional view (shape Y) of an example of the vibration isolator of the present invention. FIG. 4 is a BB cut surface (shape Y) of an example of the vibration isolator of the present invention. FIG. 5 is a partially enlarged sectional view showing a sectional shape when the shape of the second orifice is changed. FIG. 6 is a graph in which the dynamic spring constant when the shape of the second orifice is changed is plotted against the frequency.

  The anti-vibration device 1 shown in FIGS. 1 to 5 is an example of an automobile engine mount. In this example, the first metal member 2 has a screw hole 3 and is screwed to an engine that is a vibration source. Moreover, the 2nd metal member 4 is connected to a support body by the bolt hole 6 via the attachment members 5a and 5b welded to it. The first metal member 2 and the second metal member 4 are connected to each other via a rubber elastic member 7, and the elastic member 7 absorbs vibration transmitted from the vibration source to the first metal member 2. This structure prevents vibration from being transmitted from the second metal member 4 to the support through the mounting members 5a and 5b.

  The vibration isolator 1 is provided with a liquid chamber having a rubber elastic member 7 as a part of the wall, and the liquid chamber is filled with an incompressible fluid and sealed. The liquid chamber includes a pressure receiving chamber 8, a first equilibrium chamber 9, and at least one second equilibrium chamber 10. When the elastic member 7 made of rubber is deformed by the force from the first metal member 2 and the volume of the pressure receiving chamber 8 is reduced, the volume of fluid corresponding to the reduced amount is transferred from the pressure receiving chamber 8 to the first equilibrium. It flows into the chamber 9 or the second equilibrium chamber 10. On the contrary, when the volume of the pressure receiving chamber 8 increases, the fluid of the volume corresponding to the increased amount flows into the pressure receiving chamber 8 from the first equilibrium chamber 9 or the second equilibrium chamber 10.

  The pressure receiving chamber 8 and the first equilibrium chamber 9 are separated by a partition member 11. The partition member 11 is formed of a hard material such as reinforced plastic or metal and does not easily deform even when the volume of the pressure receiving chamber 8 changes. The pressure receiving chamber 8 and the first equilibrium chamber 9 are communicated with each other by a first orifice 12 that is a damping flow path that bypasses the partition member 11, and vibration is caused by a flow resistance when the fluid moves in the first orifice 12. Can be attenuated. In general, the flow of fluid in the orifice when vibration is applied is greatly limited in the frequency region exceeding the liquid resonance frequency, and the dynamic spring constant increases. In addition, the loss factor increases near the liquid resonance frequency. If the dynamic spring constant is small, vibration transmission can be reduced, and if the loss coefficient is large, the shock can be reduced. Therefore, it must be designed to have a liquid resonance frequency that can efficiently absorb vibrations and shocks of the target frequency.

  Here, the liquid resonance frequency is determined by the ratio (S / L) between the cross-sectional area (S) and the length (L) of the orifice, and thus absorbs vibrations in a low frequency region as required by an automobile engine mount, for example. In order to alleviate the shock, it is necessary to reduce the ratio (S / L), and it is necessary to make the orifice elongated. However, if the cross-sectional area (S) is too small, the amount of fluid flowing is reduced and the absorption effect and the relaxation effect are lowered. Therefore, in order to reduce the ratio (S / L), the length (L) is increased to some extent. There is a need. In the present embodiment, the length (L) is increased by the first orifice 12 bypassing the periphery of the partition member 11 in a circular shape. A part of the wall of the first equilibrium chamber 9 is constituted by a diaphragm 13, and the diaphragm 13 is deformed as the fluid flows into the first equilibrium chamber 9, and the volume of the first equilibrium chamber 9 can be increased. It has become.

  However, if only the first orifice 12 having such a small ratio (S / L) is used, vibrations in the low frequency region can be absorbed, but vibrations in a higher frequency region can be efficiently absorbed. I can't. For example, when used as an engine mount for automobiles, medium frequency vibrations of about 100 to 600 Hz are generated from the rotational speed of the engine and various members driven in relation to the engine speed. The vibration could not be absorbed efficiently. The second equilibrium chamber 10 and the second orifice 14 described below are provided to effectively absorb such vibrations in the middle frequency range.

The liquid-filled vibration isolator of the present invention is characterized by having a second equilibrium chamber 10 and a second orifice 14 in addition to the first equilibrium chamber 9 and the first orifice 12. The pressure receiving chamber 8 and the second equilibrium chamber 10 are communicated with each other via the second orifice 14. A thin portion 15 is formed in a part of the wall of the second equilibrium chamber 10, and the thin portion 15 is deformed as the fluid flows from the pressure receiving chamber 8 into the second equilibrium chamber 10. The volume of the two equilibrium chambers 10 is increased, and the thin portion 15 is deformed as the fluid flows from the second equilibrium chamber 10 to the pressure receiving chamber 8, and the volume of the second equilibrium chamber 10 is decreased. Here, the orifice means a portion where the flow path is narrower than the regions on both sides thereof, and the minimum cross-sectional area (S ₀ ) of the second orifice 14 is the maximum cross-sectional area in the second equilibrium chamber 10 ( It may be smaller than both S ₁ ) and the maximum cross-sectional area of the pressure receiving chamber 8. Here, these cross-sectional areas are perpendicular to a line (a CC line in FIGS. 1 and 2) connecting the center of the first metal member 2 and the center of the second metal member 4 (for example, It means a cross-sectional area when cut along the cutting plane shown in FIGS. Normally, the maximum cross-sectional area of the pressure receiving chamber 8 is larger than the maximum cross-sectional area (S ₁ ) of the second equilibrium chamber 10, and the volume of the pressure receiving chamber 8 is larger than the volume of the second equilibrium chamber 10.

By providing such a second orifice 14, it is possible to efficiently absorb vibrations having a frequency different from the frequency absorbed by the first orifice 12, and to exhibit vibration-proof performance according to the application. it can. In particular, since the resonance frequency is determined by the ratio (S / L) of the cross-sectional area (S) and length (L) of the orifice, the pressure receiving chamber 8 is provided by providing a short orifice that does not make the flow path too narrow. The resonance frequency of the liquid going back and forth between the first and second equilibrium chambers 10 becomes high, and vibrations having a relatively high frequency can be efficiently absorbed. Specifically, after setting the length of the second orifice to be short, the ratio (S ₁ ) of the maximum cross-sectional area (S ₁ ) in the second equilibrium chamber 10 and the minimum cross-sectional area (S ₀ ) of the second orifice 14. / S ₀ ) is preferably an orifice structure with 1.2 to 3. When the ratio (S ₁ / S ₀ ) is less than 1.2, the vibration absorption effect due to the presence of the second orifice 14 may be insufficient. On the other hand, if the ratio (S ₁ / S ₀ ) exceeds 3, it may be difficult to integrally mold the second equilibrium chamber 10 and the second orifice 14.

  The number of second equilibrium chambers 10 provided in the liquid-filled vibration isolator 1 of the present invention is not particularly limited. However, as the number of second orifices 14 increases, the vibration absorption effect increases. It is preferable to provide more than one. From the viewpoint of securing the front-rear and left-right balance, it is more preferable to provide four or more second equilibrium chambers 10, thereby further increasing the vibration absorption effect. On the other hand, if the number of second equilibrium chambers 10 is too large, the static spring constant decreases and it becomes difficult to support the load. Therefore, the number of second equilibrium chambers 10 is preferably 8 or less. In the example of FIGS. 1 to 5, four second equilibrium chambers 10 are provided.

As shown in FIG. 5, an example in which the shape of the second orifice 14 is changed (X, Y, and Z), and an example in which the second orifice 14 is not provided while having a space corresponding to the second equilibrium chamber 10 (A ), And an example (conventional product: B) having neither the second equilibrium chamber 10 nor the second orifice 14, a graph plotting the frequency on the horizontal axis and the dynamic spring constant on the vertical axis is shown in FIG. 6. Here, for the shape X, the ratio (S ₁ / S ₀ ) is 1.47. When the shape is Y, the ratio (S ₁ / S ₀ ) is 1.92, and when the shape is Z, the ratio (S ₁ / S ₀ ) is 2.5. As can be seen from FIG. 6, in the case of the shape A and the shape B, which are examples having no second orifice 14, no minimum value is recognized in the middle frequency region, but in the shapes X, Y and Z, about 450 Hz and about Minimal values were observed at 350 Hz and about 200 Hz, and it was found that efficient vibration absorption was possible at each frequency. By simply adjusting the cross-sectional area of the second orifice 14 to change the ratio (S ₁ / S ₀ ), it is possible to easily control the minimum value frequency of the dynamic spring constant in the middle frequency range, and to improve the vibration proof performance. It is very easy to design.

In the liquid-filled vibration isolator 1 of the present invention, the second equilibrium chamber 10 and the second orifice 14 are integrally formed with a rubber elastic member 7. Therefore, it is possible to obtain the vibration absorption effect in the medium frequency region as described above without increasing the number of parts. Even if a mold having a complicated structure is not used, if the maximum cross-sectional area (S ₁ ) in the second equilibrium chamber 10 is not more than three times the minimum cross-sectional area (S ₀ ) of the second orifice 14, the mold Since the mold can be removed from the mold, the production cost hardly increases. Even if the ratio (S ₁ / S ₀ ) is so small that die cutting can be performed in this way, it is surprising that an effective vibration absorbing effect in the middle frequency range could be obtained. It became clear that it was possible to balance performance.

  Although the manufacturing method of the liquid enclosure type vibration isolator 1 of this invention is not specifically limited, The 1st metal member 2 and the 2nd metal member 4 are mounted | worn in a metal mold | die, and unvulcanized | cured in a metal mold | die. A method of vulcanizing and bonding the first metal member 2 and the second metal member 4 by vulcanizing after filling with rubber is suitably employed. In the example of FIGS. 1 to 5, a mold set including an upper mold, a lower mold, and a middle mold that can be divided into two is used, and the first metal member 2 and the second metal member 4 are placed therein. It can be manufactured by mounting, filling the space in the mold with unvulcanized rubber by injection molding, and heating and vulcanizing. At this time, it is preferable to have the process of extracting the convex part of the metal mold | die corresponding to the 2nd equilibrium chamber 10 and the 2nd orifice 14 from a vulcanized rubber molded product after vulcanization. That is, even if one of the upper mold and the lower mold has a convex portion corresponding to the shape of the second equilibrium chamber 10 and the second orifice 14, it can be removed from the mold while the rubber is hot after vulcanization. Therefore, it can be manufactured by the same operation as a conventional product that does not have the second equilibrium chamber 10 and the second orifice 14. That is, it can be manufactured by the same operation as a conventional product simply by changing the shape of the mold.

  The liquid filled vibration isolator 1 of the present invention thus obtained can be used as a vibration isolator for various uses such as a mount. In particular, the present invention is suitably used for an engine mount that is desired to reduce the dynamic spring constant in the middle frequency range while increasing the static spring constant, particularly for an automobile engine mount.

DESCRIPTION OF SYMBOLS 1 Vibration isolator 2 1st metal member 3 Screw hole 4 2nd metal member 5a, 5b Mounting member 6 Bolt hole 7 Elastic member 8 Pressure receiving chamber 9 1st equilibrium chamber 10 2nd equilibrium chamber 11 Partition member 12 1st orifice 13 Diaphragm 14 Second orifice 15 Thin part

Claims (4)

It has a first metal member connected to one of the vibration source side or the support side and a second metal member connected to the other, and the first metal member and the second metal member are interposed via a rubber elastic member. And a liquid chamber having the elastic member as a part of the wall, and the liquid chamber is sealed with an incompressible fluid.
The liquid chamber includes a pressure receiving chamber, a first equilibrium chamber, and at least one second equilibrium chamber;
The pressure receiving chamber and the first equilibrium chamber are separated by a partition member and communicated by a first orifice that is a damping channel that bypasses the partition member, and a part of the wall of the first equilibrium chamber forms a diaphragm. As the fluid flows into the first equilibrium chamber, the volume of the first equilibrium chamber can be increased,
The pressure receiving chamber and the second equilibrium chamber are communicated with each other by a second orifice, and the second equilibrium chamber and the second orifice are integrally formed of a rubber elastic member, and the maximum sectional area (S _{1) in} the second equilibrium chamber is obtained. ) Is larger than the minimum cross-sectional area (S ₀ ) of the second orifice, and has a thin wall portion in a part of the wall of the second equilibrium chamber, and the thin wall portion becomes smaller as the fluid flows into the second equilibrium chamber. A liquid-filled type vibration damping device, wherein the volume of the second equilibrium chamber can be increased by deformation. 2. The liquid-filled type protection according to claim 1, wherein a ratio (S ₁ / S ₀ ) of a maximum cross-sectional area (S ₁ ) in the second equilibrium chamber to a minimum cross-sectional area (S ₀ ) of the second orifice is 1.2 to 3. Shaker.   The liquid-filled vibration isolator according to claim 1 or 2, wherein 2 to 8 second equilibrium chambers are provided.   The first metal member and the second metal member are mounted in a mold, filled with unvulcanized rubber in the mold and vulcanized, and the first metal member and the second metal member are vulcanized and bonded. In this case, the liquid according to any one of claims 1 to 3, further comprising a step of extracting the convex portions of the mold corresponding to the second equilibrium chamber and the second orifice from the vulcanized rubber molded product after vulcanization. A manufacturing method of an enclosed vibration isolator.

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