JP4169229B2 - Liquid filled vibration isolator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid-filled vibration isolator that supports a vibration member, such as an automobile engine, with respect to a fixed member.
[0002]
[Prior art]
When vibration-supporting the vibration body, a liquid-sealed liquid chamber communicated by an orifice passage is defined inside the rubber elastic body as a vibration-proof member, and these liquid systems resonate with the vibration when vibration is input. It is known that the anti-vibration effect is great. At present, various liquid-sealed vibration isolators using this mechanism are provided. Furthermore, recently, some of the vibration isolator incorporates a fluid liquid system that changes into a plurality of flow capacities so as to respond to the respective frequencies of an automobile engine or the like having a plurality of frequencies. is there.
[0003]
[Problems to be solved by the invention]
However, such considerations are based on the assumption that the vibration input direction is the load direction, and if a vibration other than the load direction is input, the contrivance is not useful. Since an automobile or the like moves, it goes without saying that the vibration input direction of the vibration isolator incorporated therein is not limited to the load direction. For this reason, a dedicated vibration isolator for preventing vibrations in directions other than the load direction is provided.
The present invention solves such a problem, and enables a liquid-filled vibration isolator capable of isolating vibrations in directions other than the load direction with a single vibration isolator.
[0004]
[Means for Solving the Problems]
Under the above problems, the present invention accommodates and arranges the inner metal fitting attached to one member to be vibration-proof connected inside the outer metal fitting attached to the other member to be vibration-proof connected, While the outer metal fitting is connected by a rubber elastic body, a part of the chamber wall is made of the rubber elastic body on one side in the load direction of one member across the partition member provided on the outer metal fitting side, and vibration input A pressure receiving chamber that sometimes causes internal pressure fluctuations is formed on the other side, and an equilibrium chamber in which a part of the chamber wall is made of an elastic film and volume change is allowed is formed. In the liquid-filled vibration isolator provided with an orifice passage that allows the pressure receiving chamber and the equilibrium chamber to communicate with each other, the outer side of the chamber wall of the pressure receiving chamber that is made of a rubber elastic body and does not face the load direction is covered. Form a window in the outer bracket Since the chamber wall and the chamber wall lies in the inner periphery of the outer fitting along parallel to the inner side of the window to be thin it has provided a liquid filled vibration isolating device being characterized in that it possible to bulge out window is there.
[0005]
When vibration is input from a direction other than the load direction, for example, from the lateral direction, the liquid does not easily move between the pressure receiving chamber and the equilibrium chamber, and the liquid in the pressure receiving chamber having a large volume resonates with the vibration in the pressure receiving chamber. Moving. For this reason, the spring constant increases dramatically from above the frequency, and as a result, the vibration cannot be cut off. In this case, even if an attempt is made to adjust the resonance frequency, it cannot be easily performed in a pressure receiving chamber having no chamber wall that acts as an elastic film. However, as in the present invention, a window is formed in the outer metal fitting that covers the outside of the chamber wall of the pressure receiving chamber that does not face the load direction, and the chamber wall existing inside the window is thinned so that the chamber wall bulges outside the window. If this is possible, the wall of the chamber will exhibit an elastic membrane action against vibrations from the lateral direction, so the resonance frequency can be adjusted very easily by adjusting its elasticity. Can be.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings, taking a suspended engine mount as an example. FIG. 1 is a longitudinal sectional view of a liquid-filled vibration isolator showing an example of the present invention, and FIG. 3 is a side view. The liquid-filled vibration isolator (hereinafter referred to as a vibration isolator) includes an inner metal fitting 1 and an inner metal fitting. 1, an outer metal fitting 2 that accommodates and arranges 1 inside, a rubber elastic body 3 interposed between the inner metal fitting 1 and the outer metal fitting 2, an upper lid 4 that covers the outer metal fitting 2, and an outer metal fitting 2 and an upper lid 4. It consists of the partition member 5 etc. which are accommodated between.
[0007]
The inner metal fitting 1 has a substantially cylindrical shape and is inserted vertically with respect to the outer metal fitting 2. A screw hole 6 for fastening a vibrating body is formed on the bottom surface of the inner metal fitting 1, and a stirring plate called a device 7 for stirring a liquid is attached to the upper part. The outer metal fitting 2 has a cylindrical shape arranged concentrically with the inner metal fitting 1, and an upper lid 4 having a cup faced down is fixed to the upper portion thereof by caulking or the like. The upper lid 4 is a rubber elastic body in which a core metal 8 is sealed around a side wall and an upper wall, and a thin elastic film 9 is formed at the center of the upper wall where the core metal 8 is interrupted.
[0008]
The rubber elastic body 3 connects the inner metal fitting 1 and the outer metal fitting 2 below the device 7, but the upper surface thereof descends obliquely downward from the inner metal fitting 1 to reach the inner periphery of the outer metal fitting 2. A thin wall is formed along the inner periphery of the outer metal fitting 2 and rises to the connecting portion with the upper lid 5 (FIG. 1). Accordingly, the space 10 having a V-shaped cross section is wrapped around the inner metal fitting 1 above the upper surface of the rubber elastic body 3.
[0009]
The partition member 5 has a hat shape having an indented portion 11 on the upper surface, and is fixed by sandwiching the flange portion at the lower end between the outer metal fitting 2 and the upper lid 4. The partition member 5 is also a rubber elastic body in which a core metal 12 is enclosed around the side wall and the upper wall, and the center of the upper wall where the core metal 12 is interrupted is formed in a relatively thin elastic film 13. In this state, the partition member 5 is covered with a gap above the space 10 and the inner metal fitting 1, and the vertical wall around the recessed portion 11 is pressed against the upper lid 4.
[0010]
Accordingly, the gap between the partition member 5 and the upper lid 4 forms an emptied portion 14 having two elastic films 9 and 13, and the partition member 5 including the space 10 and the rubber. A void portion 15 that is also isolated from the gap between the elastic body 3 and the first metal fitting 1 is formed. Therefore, if the outer metal fitting 2 and the upper lid 4 are fixed in the liquid, the two empty portions 14 and 15 form a liquid chamber in which the liquid is sealed. Here, the lower liquid chamber is the pressure receiving chamber 15, and the upper liquid chamber is the equilibrium chamber 14.
[0011]
The pressure receiving chamber 15 and the equilibrium chamber 14 are communicated with each other through an orifice passage 16. In this example, the orifice passage 16 is formed by the upper lid 4 and the partition member 5. FIG. 2 is a plan view of the partition member 5. A hole 17 is formed in the flange portion, and a weir 18 that protrudes until the end faces the end of the hole 17 and the side wall is pressed against the side wall of the upper lid 4 located outside. A part of the vertical wall that is formed and rises upward from the recessed portion 11 on the side opposite to the hole 17 from the weir 18 is cut out and used as an outflow inlet 19. As a result, the orifice passage 16 is formed between the side wall of the upper lid 4 and the side wall of the partition member 4, and the liquid passing therethrough enters and exits the pressure receiving chamber 15 and the equilibrium chamber 14 through the hole 17 and the outflow inlet 19.
[0012]
FIG. 4 is an explanatory view showing the state of attachment of the engine when the above apparatus is applied to an automobile engine mount. The engine side attachment member 20 is fixed to the screw hole 6 of the inner metal fitting 1 with a bolt 21. A plurality of body-side mounting members 22 are attached to the outer metal fitting 2 (the outer metal fitting 2 is housed and protected in the housing 23), and the body-side mounting member 22 is fixed to the body with bolts (not shown). To do.
[0013]
As described above, when the engine vibrates, this vibration isolator operates to block transmission of the engine vibration to the body side. However, the vibration input direction and the load direction (up and down direction) in which the engine weight is applied. If the two are in agreement, the device performs a vibration isolation function accordingly. However, when vibration is input in a direction different from the load direction, the direction does not face the elastic films 9 and 13 forming the chamber wall of the equilibrium chamber 14 (because it is not a right angle). As described above, there is only one anti-vibration function that is caused in cooperation with
[0014]
Therefore, the present invention makes it possible to form the window 24 in the outer metal fitting 2 and to allow the rubber elastic body 3 constituting the chamber wall of the pressure receiving chamber 15 existing inside the window 24 to bulge outside the window 24. It is designed to allow elastic membrane action. By doing so, even if vibration is input from the front and rear and the left and right directions, the rubber elastic body 3 swells out of the window 24 and keeps the softness of the spring and blocks vibration transmission. Therefore, in some cases, another anti-vibration device that prevents vibration in the front-rear and left-right directions is unnecessary.
[0015]
Since the outside of the window is covered with the housing 23 described above, there is no possibility of the rubber elastic body 3 being torn (in order to make the elastic film action of the rubber elastic body 3 easier to perform, the outside of the window 24). The housing 23 is preferably provided with a vent hole 25). In this case, the position, size, and number of the windows 24 are set as appropriate, but it is preferable to form them in the direction in which vibration is input. From this point of view, it is preferable that four anti-vibration devices for automobiles are formed on the front and rear and the right and left for convenience.
[0016]
【The invention's effect】
As described above, since the present invention is as described above, even if vibration in a direction other than the load direction is input, the chamber wall of the pressure receiving chamber acts as an elastic film to maintain the softness of the spring and exhibit a vibration isolation function. To do.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a liquid filled vibration isolator showing an example of the present invention.
FIG. 2 is a plan view of a partition member constituting a liquid-filled vibration isolator showing an example of the present invention.
FIG. 3 is a side view of a liquid filled vibration isolator showing an example of the present invention.
FIG. 4 is an explanatory diagram of a usage situation of a liquid-filled vibration isolator showing an example of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Inner metal fitting 2 Outer metal fitting 3 Rubber elastic body 5 Partition member 14 Equilibrium chamber 15 Pressure receiving chamber 16 Orifice passage 24 Window

Claims (2)

The inner metal fitting attached to one member to be anti-vibration connected is accommodated and arranged inside the outer metal fitting attached to the other member to be anti-vibration connected, and the inner metal fitting and the outer metal fitting are connected by a rubber elastic body. A pressure receiving chamber in which a part of the chamber wall is formed of the rubber elastic body and causes an internal pressure fluctuation at the time of vibration input on one side in the load direction of one member across the partition member provided on the outer metal fitting side. On the other side, a part of the chamber wall is formed of an elastic film to form an equilibrium chamber in which the volume change is allowed, and liquid is sealed in the pressure receiving chamber and the equilibrium chamber, and the pressure receiving chamber is balanced. In the liquid-filled vibration isolator having an orifice passage communicating with the chamber, a window is formed on the outer metal fitting that covers the outside of the chamber wall of the pressure receiving chamber that does not face the load direction and is configured by a rubber elastic body. Along the inner circumference of The chamber wall and the chamber wall lies inside the window thin Te liquid filled vibration isolating device being characterized in that it possible to bulge out window.   The liquid filled vibration isolator according to claim 1, wherein a plurality of windows are provided.

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