JPS6262034A - Vibro-isolating supporter - Google Patents

Abstract

PURPOSE:To improve a damping effect, by providing a partitioning member, having a throttle passage, in a fluid chamber, partitioned between a load supporting elastic member and an inertia mass unit, in the case of a device which mounts the load supporting elastic member and the inertia mass unit to be interposed between each mounting member in a vibrating body side and a supporting body side. CONSTITUTION:A vibro-isolating supporter, suitable for a power unit of a vehicle, has a mounting member 11 in a car body side and a mounting member 14 in a power unit side. The supporter, mounting a load supporting elastic member 19 of rubber or the like to be interposed between a collar 18 fixed to the upper end of a cylinder 12 in the mounting member 11 and the head part of an anchor bolt 16 in the mounting member 14 while supporting an inertia mass unit 21 to be vertically movably suspended through an elastic material 20 to the peripheral bottom end of the collar 18, partitions a fluid chamber 23 between the unit 21 and the above described elastic member 19. Here the supporter mounts a partitioning member 24, having in its inside a fluidization chamber 25, to be fitted to the internal peripheral bottom end of the collar 18 so as to divide the fluid chamber 23 into two divided chambers 26, 27, while the fluidization chamber 25 floatably houses an orifice plate 28 having a throttle passage 29.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a vibration isolating support device suitable for supporting a power unit of a vehicle, and more particularly to a vibration isolating support device with improved vibration damping ability.

(Prior art) As a conventional anti-vibration support device, for example, Japanese Patent Application Laid-Open No. 59-2
A fluid man mount as described in Japanese Patent No. 31239 is known. This fluid man mount combines a mounting member connected to a vibration source and a base member for mounting the vibration source with an elastic member to define a fluid chamber therein, and an effective area of the elastic member within the fluid chamber. The fluid chamber is separated into two compartments by floatingly supporting a weight having a larger effective area across the body by an elastic body, and an orifice is formed in the weight to communicate between the two compartments.

In this fluid man mount, the fluid chamber expands and contracts as vibrations occur, causing fluid to flow between the compartments through the orifice, and vibrations are damped by the resistance when the fluid passes through the orifice.・(Problem to be solved by this invention) However,
In such a conventional anti-vibration support device, one of the compartments defined by the elastic member and the weight is communicated with the other compartment through the orifice, so the change in volume of the one compartment is small; There was a problem in that the flow rate of fluid passing through the orifice was small and a sufficient damping effect could not be obtained. That is, the volume of the one compartment changes due to the deformation of the elastic member, but the weight causes a displacement that cancels out the change in volume due to the deformation of the elastic member, so the change in volume becomes small. As a result, the fluid flow rate passing through the orifice was small, and the damping force was also small.

(Means for Solving the Problems) The vibration isolating support device according to the present invention has been made for the purpose of solving the above-mentioned conventional problems. a mounting member provided on the mounting member, an elastically deformable load supporting elastic body interposed between these mounting members to displaceably support the vibrating body to the support body, and an elastic body disposed on one of the mounting members. an inertial mass body that is attached and expandably and contractibly defines a fluid chamber filled with fluid together with the load-supporting elastic body between the attachment members;
In the vibration-proof support device, a partition member is provided on one of the mounting members, and a first compartment is defined by the partition member and the load-supporting elastic body, and a first compartment is defined by the partition member and the inertial mass body. The fluid chamber is separated into a second compartment, and a throttle passage is formed in the partition member to communicate the first compartment and the second compartment.

(Function) According to the vibration isolating support device according to the present invention, when vibration occurs, the load supporting elastic body deforms and the volume of the first compartment changes. The first compartment is separated from the second compartment, which expands and contracts with the displacement of the inertial mass body, by a partition member, and communicates with the second compartment via a throttle passage formed in the partition member. Therefore, the first compartment undergoes a relatively large change in volume in response to the deformation of the load-supporting elastic body, that is, the amplitude of vibration, without being affected by the displacement of the inertial mass body. As a result, the flow rate of the fluid flowing between the first compartment and the second compartment via the orifice is also large, and a large damping force can be exerted to effectively damp vibrations.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIGS. 1 and 2 show an embodiment of a vibration isolation support device according to the present invention. Note that this embodiment is applied to support of a power unit of a vehicle.

First, to explain the structure, in FIG. 1, reference numeral 11 is a mounting member on the vehicle body side in which the lower end of a cylinder 12 is integrally closed by a bottom plate 13, and 14 is a substantially four-shaped plate 15 through which an anchor bolt 16 is fixed. This is a mounting member on the power unit side. The mounting member 11 on the vehicle body side has screws 1 passing through the bottom plate 13.
7 is fixed to the vehicle body, and the power unit side mounting member 14
is fixed to the power unit by an anchor bolt 16.

Between the collar 18 fixed to the upper end of the cylinder 12 of the mounting member 11 on the vehicle body side and the head of the anchor bolt 16 of the mounting member 14 on the power unit side, there is a substantially cylindrical load supporting member made of a rubber-like elastic material. An elastic member 19 is interposed. The load supporting elastic member 19 has an outer circumferential surface bonded by baking to the inner circumferential surface of the collar 18 and an inner circumferential surface bonded by baking to the head of the anchor bolt 16, and supports the load of the power unit and deforms as the power unit is displaced. do. Further, at the lower end of the outer periphery of the collar 18 of the mounting member 17 on the vehicle body side, an elastic body 20 of a predetermined spring constant made of a rubber-like elastic material is attached to a predetermined X
An inertial mass body 21 of I is suspended within the cylinder 12 so as to be movable up and down. The inertial mass body 21 suspended by the elastic body 20 defines a gas chamber 22 in which compressible fluid such as air is sealed together with the mounting member 11 on the vehicle body side, and together with the load supporting elastic member 19, it defines a gas chamber 22 in which compressible fluid such as air is sealed. A liquid chamber (fluid chamber) 23 filled with incompressible fluid is defined. Gas chamber 22
The compressible fluid sealed therein elastically supports the inertial body 21 together with the elastic body 20 .

Further, a partition member 24 defining a flow chamber 25 therein is fitted to the lower end of the inner periphery of the collar 18 of the mounting member 11 on the vehicle body side. This partition member 24 separates the inside of the liquid chamber 23 into a first compartment 26 on the load supporting elastic body 19 side and a second compartment 27 on the inertial mass body 21 side. The first compartment 26 expands and contracts as the load supporting elastic body 19 deforms, and the second compartment 27 expands and contracts as the inertial mass body 21 moves in the vertical direction. The floating chamber 25 communicates with the first compartment 26 and the second compartment 27 via communication holes 24a formed in the upper and lower walls of the partition member 24, and has an orifice plate 28 inside which can close the communication hole 24a floating. are doing. The orifice plate 28 is connected to the communication hole 2 of the partition member 24.
Orifice (throttling passage) 2 at a position corresponding to one of 4a
9 is formed. This orifice plate 28 can be brought into close contact with the inner wall of the floating chamber 25 of the partition member 24 according to the fluid pressure difference between the front and back sides as the fluid flows between the first compartment 26 and the second compartment 27 via the floating chamber 25. Float.

Next, the operation of this embodiment will be explained.

First, when a large-amplitude, low-frequency vibration of around 10 Hz, which causes engine shake, occurs in the vehicle body due to upward acceleration from the road surface while the vehicle is running, the power unit vibrates significantly with respect to the vehicle body. Then, the load supporting elastic member 19 is greatly deformed, and the first compartment 26 of the liquid chamber 23 also expands and contracts.

Therefore, in the second compartment 27, the inertial mass body 21 is connected to the elastic body 20.
It expands and contracts by being displaced by deformation, and fluid flows between the first compartment 26 and the second compartment 27 via the floating chamber 25 .

At this time, the first compartment 26 is not affected by the displacement of the inertial mass body 21 and undergoes a large volume change according to the deformation of the load-supporting elastic member 19, that is, the amplitude of the vibration. The flow rate of fluid flowing between the compartment 26 and the second compartment 27 also increases. Therefore, the fluid pressure difference between the front and back of the temporary orifice 280 also increases, causing the orifice plate 2
8 closely contact the upper and lower inner walls of the floating chamber 25 depending on the fluid flow direction to close the communication hole 24a. As a result, the first branch 2
6 and the second compartment 27 are communicated only through an orifice 29, through which the large flow rate of fluid passes. Therefore, a large damping force can be obtained,
Vibrations can be quickly damped and engine shake can be completely prevented.

On the other hand, if a small amplitude vibration with a frequency higher than the resonance frequency of the inertial mass body 21 occurs in the power unit, which causes muffled noise in the vehicle interior such as engine secondary vibration, the load supporting elastic member 1
9 undergoes a small deformation, and the first compartment 26 of the liquid chamber 23 expands and contracts. The orifice plate 28 does not follow the high-frequency vibrations and moves up and down, but remains in the liquid due to inertia, and does not come into close contact with the inner wall of the floating chamber 25 (the first subchamber 2
6 and the second compartment 27 communicate with each other over a relatively large area through the floating chamber 25 and the communication hole 24a of the partition member 24, and the liquid in the liquid chamber 23 generates pulsations in response to vibrations. At this time, the inertial mass body 21 vibrates in an opposite phase to the mounting member 14 on the power unit side due to the pulsation within the liquid chamber 23. That is, the inertial mass body 21 remains stationary and causes the fluid in the liquid chamber 23 to pulsate to cancel out the pulsations described above. For this reason,
The overall spring constant becomes smaller against high-frequency vibrations, reducing high-frequency vibrations transmitted to the vehicle body.

In this way, with this anti-vibration support device, the loss factor against low frequency vibrations can be increased as shown in Figure 2 without increasing the spring constant against high frequency vibrations. It is possible to prevent the occurrence of muffled noise in the vehicle interior, and it is also possible to prevent engine shake.

(Effects of the Invention) As explained above, according to the vibration isolating support device according to the present invention, when vibrations, particularly low frequency vibrations, occur, a large flow of fluid flows through the throttle passage, so that vibrations can be effectively suppressed. This has the effect that it can be attenuated to

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the vibration isolation support device according to this invention, and FIG. 2 is a characteristic diagram of vibration frequency vs. loss factor. 11.14... Mounting member, 19... Load supporting elastic body, 20... Elastic body, 21...: Inertial mass body, 23... ...liquid chamber (fluid chamber), 24...partition member, 26...first branch chamber, 27...second branch chamber, 29...orifice. Ill Figure jA J'1 /7. /+: J gong 4th dimension zero age /9: A11BH! II Sex @M 20: #fr'L nom 2I: Inertia amount 旙 23: Blend A1t 24: ＾τυI Japanese material 26: Negative l#1 27: '1! +2 dress゛1 2? ;Kori 1st word 2nd figure Hz

Claims (1)

[Claims] a mounting member provided on the vibrating body, a mounting member provided on the support body, and an elastically deformable load-supporting elastic body that is interposed between these mounting members and displaceably supports the vibrating body on the support body. and an inertial mass body that is attached to one of the attachment members via an elastic body and expandably and contractibly defines a fluid chamber filled with fluid together with the load-supporting elastic body between the attachment members. In the support device, a partition member is provided on one side of the mounting member, and a first compartment is defined by the partition member and the load supporting elastic body, and a second compartment is defined by the partition member and the inertial mass body. A vibration damping support device, characterized in that the fluid chamber is separated from the other, and a throttle passage is formed in the partition member to communicate the first compartment and the second compartment.