JPH02209645A - Vibration proofing device - Google Patents

Abstract

PURPOSE:To prevent leakage of liquid from a liquid chamber and improve durability of a vibration proofing device by forming an elastic membrane constructing the liquid chamber of the vibration proofing device out of an elastic body having excellent ozone-proof property different from an elastic body valcanizedly close-fitted to an inner cylinder. CONSTITUTION:A main body rubber 18 is arranged as an elastic body between an inner cylinder 14 and an outer cylinder 12. This main body rubber 18 surrounds the outer circumferential face of the inner cylinder 14, and also an intermediate cylinder 16 is buried in the rubber. A box shaped diaphragm 26, one of constructing members of a sub-liquid chamber 28, is fitted on the upper cut-out part 24. This diaphragm 26 as an elastic membrane is formed out of a rubber having excellent ozone-proof property. Thus, leakage of liquid from the liquid chamber is prevented, and durability of the vibration proofing device can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vibration isolating device for absorbing vibrations, which is used in engine mounts, body mounts, cab mounts, etc.

[Prior Art] A vibration isolator has an inner cylinder and an outer cylinder wrapped around each other with an elastic body, and in order to obtain a sufficient damping effect, a main liquid chamber and a sub-liquid chamber provided inside the vibration isolator are filled with viscous liquid. The main liquid chamber and the sub-liquid chamber are communicated through a restricted passage (Japanese Patent Laid-Open No. 62-224746).

In conventional vibration isolators, the diaphragm constituting the sub-liquid chamber is vulcanized and bonded together with the so-called main body rubber, which spans the inner cylinder and the outer cylinder. Same quality rubber material is used.

However, since the main body rubber is required to have dynamic properties and durability, a rubber material whose main component is natural rubber, which has excellent dynamic properties and durability, is often used, and therefore the wall thickness is as thin as 1 mm to 2 mm. The diaphragm will also be made of a rubber material whose main component is natural rubber.

However, rubber materials made mainly of natural rubber have poor ozone resistance, so the diaphragm that is exposed to the atmosphere is eroded by ozone, resulting in cracks in the diaphragm, which can cause liquid leakage from the sub-liquid chamber. Become.

Additionally, by first vulcanizing and adhering the diaphragm and then vulcanizing and adhering the main body rubber, it is possible to manufacture the diaphragm using a rubber material with excellent ozone resistance by making the material different from the main body rubber. In this case, since vulcanization bonding must be performed twice, the manufacturing efficiency of the vibration isolator is not good, and there is a risk that the diaphragm may be damaged when the semi-finished product is placed in a mold for the second vulcanization bonding.

[Problems to be Solved by the Invention] In view of the above-mentioned facts, an object of the present invention is to provide a vibration isolating device that prevents cracks from occurring in the rubber film and does not cause liquid leakage.

[Means for Solving the Problems] The present invention provides an elastic body in which an elastic body is spanned between an inner cylinder and an outer cylinder which are connected to a vibration generating part and a vibration receiving part, respectively. A vibration isolating device in which a first liquid chamber and a second liquid chamber are communicated through a restriction passage, wherein an elastic membrane that is one of the members constituting the first liquid chamber is connected to the elastic body. The liquid chamber is manufactured separately and the periphery is brought into close contact with the elastic body to seal the liquid chamber.

[Function] In the present invention having the above configuration, the elastic body is spanned between the inner cylinder and the outer cylinder, and the first liquid chamber and the second liquid chamber, which are provided on opposite sides of each other via the inner cylinder, are restricted. The vibration isolating device communicates with the first liquid chamber through a passage, and the elastic membrane, which is one of the constituent members of the first liquid chamber, is manufactured separately from the elastic body, and the periphery is brought into close contact with the elastic body. Since the liquid chamber is sealed using the rubber material, the elastic membrane can be manufactured from a rubber material with excellent ozone resistance. Therefore, cracks caused by ozone can be prevented from occurring in the elastic membrane, and liquid leakage from the first liquid chamber can be prevented.

[First Embodiment] FIG. 1 shows a longitudinal sectional view of a first embodiment of a vibration isolator 10 according to the present invention. In this vibration isolator 10, the outer cylinder 12
and the inner cylinder 14 are arranged with parallel axes, one of which is connected to the body of an automobile (not shown), and the other to an engine.

An intermediate cylinder 16 is disposed between the outer cylinder 12 and the inner cylinder 14. A main body rubber 18 as an elastic body is disposed between the inner cylinder 14 and the outer cylinder 12, and this main body rubber 18 surrounds the outer peripheral surface of the inner cylinder 14 and embeds the intermediate cylinder 16. The main body rubber 18 is made of a rubber material whose main component is natural rubber, which has excellent properties such as durability.

Further, a cavity 20 is formed above the inner cylinder 14 of the main body rubber 18 (on the upper side in FIG. 1). This cavity 20 is the first
As shown in the drawings and FIG. 3, it passes through the vibration isolation device 10 in the axial direction, and a part of the inner periphery of the intermediate cylinder 16 faces the cavity 20.

As shown in FIG. 1, the intermediate cylinder 16 has an enlarged diameter end 16A on both sides in the axial direction, and the outer peripheral surface of the end 16A is press-fitted into the inner peripheral surface of the outer cylinder 12. A diameter-reducing recess 22 is formed in the axially intermediate portion of the intermediate cylinder 16 . Also,
A part of the main body rubber 18 as an elastic body is vulcanized and bonded to the outer peripheral surface of the diameter-reducing recess 22 of the intermediate cylinder 16, and a rectangular notch 24 is provided in the diameter-reducing recess 22, with the inner cylinder 14 sandwiched therebetween. They are formed on both sides (vertical direction in FIG. 1), respectively. A box-shaped diaphragm 26, which is one of the constituent members of the sub-liquid chamber 28, is fitted into the upper notch 24, as shown in FIGS. 4 to 6.

Therefore, as shown in FIG. 1, most of the diaphragm 26 except for the periphery protrudes into the cavity 20 and is exposed to the atmosphere, and the periphery of the diaphragm 26 is exposed to the outside of the diameter-reducing recess 22. Placed. The diaphragm 26 as an elastic membrane is made of rubber with excellent ozone resistance (such as butyl rubber) with a wall thickness of 1 mm to 2 mm, so even if the diaphragm 26 comes into contact with the atmosphere, ozone will cause cracks in the diaphragm 26. It never occurs.

As shown in FIG. 4, the diaphragm 26 is formed into a thin plate shape, and a thick lip portion 30 is formed at the edge of the opening 28 to serve as a sealing material. (See FIG. 1) As shown in FIG. 1, an orifice unit 32 is fitted into the diameter-reducing recess 22 of the intermediate cylinder 16.

As shown in FIG. 7, the orifice unit 32 is composed of a pair of semicircular orifice unit pieces 32A and 132B, whose ends are brought into contact with each other to form a ring shape. An orifice 40 is formed within these orifice unit pieces 32A, 32B. The opening 28 of the diaphragm 26 is covered by the orifice unit 32, and the diaphragm 26 and the orifice unit 32 form a sub-liquid chamber in the upper part of the vibration isolator 10 (upper side in FIG. 1). Liquid chamber 3
4 is formed. Further, in the lower part of the vibration isolator 10 (lower side in FIG. 1), the orifice unit 32 and the main body rubber 18 form a main liquid chamber 36 as a second liquid chamber. The sub-liquid chamber 34 and the main liquid chamber 36 communicate with each other through openings 40A and 40B formed at the ends of the orifice 40.

The auxiliary liquid chamber 34 and the main liquid chamber 36 are filled with a viscous liquid 38 such as silicone oil. As shown in FIG. 2, the auxiliary liquid chamber 34 and the main liquid chamber 36 are connected to an orifice 40 as a restriction passage formed inside the orifice unit 32.
The viscous liquid 38 communicates with the sub liquid chamber 34 and the main liquid chamber 3 through
It is now possible to go back and forth between 6 and 6.

When manufacturing the vibration isolating device 10 according to the present invention as described above, first, the main body rubber 18 is placed between the inner cylinder 14 and the intermediate cylinder 16, and the main body rubber 18 is attached to the inner cylinder 14 and the intermediate cylinder 16. Vulcanize and adhere. And a separately manufactured diaphragm 2
6 into the notch 24 of the intermediate cylinder 16, and
6 into the cavity 20 and inserted until the thick lip portion 30 engages with the edge of the notch 24 as shown in FIG. Next, the orifice unit 32 is attached to the intermediate cylinder 16.
It is arranged around the diameter-reducing recess 22 and inserted into the outer cylinder 12 in that state. Then, by drawing the outer cylinder 12, the outer cylinder 12 is brought into close contact with the outer periphery of the end portion 16A of the intermediate cylinder 16, and the vibration isolating device 10 is completed.

[Second Embodiment] FIGS. 8 to 11 show a second embodiment of the vibration isolator 10 according to the present invention.

In this embodiment, as shown in FIG.
On the upper side of FIG. 8), a metal fitting 60 having a shape shown in FIG. 9 is disposed inside the intermediate cylinder 16. The end 60 of this metal fitting 60
A is caulked and fixed to the outer cylinder 12 together with the end 16A of the intermediate cylinder 16.

Further, the thick lip portion 30 of the diaphragm 26 is vulcanized and bonded to the metal fitting 60, and the intermediate portion of the diaphragm 26 protrudes from an opening 62 cut out in the metal fitting 60.

Therefore, in this embodiment, the diaphragm 26 is vulcanized and bonded to the metal fitting 60 as shown in FIGS. 8, 10, and 11, so that the diaphragm 26 of the seal portion 64 is uniformly tightened. Therefore, the sealing performance is further improved.

In this embodiment, a seal portion 64 is provided inside the intermediate cylinder 16.
However, the intermediate cylinder 16 and the orifice unit 32 may be sandwiched between the outer cylinder 12.

Note that when the diaphragm 26 is manufactured separately as in the present invention, it is possible to manufacture the diaphragm 26 with higher precision, which has the advantage of being useful for improving the quality of the vibration isolator 10.

Furthermore, in the case of manufacturing the vibration isolator 10 according to the present invention, only one vulcanization bonding is required, so that the manufacturing efficiency of the vibration isolator 10 does not decrease.

When in use, the auxiliary liquid chamber 34 or the main liquid chamber 36 may be damaged due to engine vibration.
The vibrations are absorbed by the resistance of the viscous liquid 38 as it moves through the orifice 40 and the other way.

During use, the bottom of the diaphragm 26 is exposed to the atmosphere, but since the diaphragm 26 can be made of synthetic rubber with excellent ozone resistance, no damage such as cracks will occur even during long-term use.

[Effects of the Invention] As explained above, the present invention makes the elastic film resistant to ozone by forming the elastic film constituting the liquid chamber of the vibration isolator separately from the elastic body that is vulcanized and bonded to the inner cylinder. Since it can be formed from an excellent elastic material, it has the effect of preventing liquid leakage from the liquid chamber and improving the durability of the vibration isolator.

[Brief explanation of the drawing]

1 to 7 show a first embodiment of the vibration isolator according to the present invention, FIG. 1 is a sectional view taken along the line II in FIG. 3, and FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1. A sectional view, FIG. 3 is a left side view, FIG. 4 is an overall perspective view of the rubber membrane, FIG. 5 is a view taken along the line V-V in FIG. 4,
6 is a view taken along the line ■-■ in FIG. 4, FIG. 7 is an exploded perspective view showing the inner and outer cylinders, intermediate cylinder, and orifice unit, and FIGS. 8 to 11 are views of the vibration isolator according to the present invention. The second embodiment is shown, FIG. 8 is a sectional view of the vibration isolator, FIG. 9 is an overall perspective view of the metal fittings, and FIG. 10 is a sectional view taken along the line X-X in FIG. 9 with the diaphragm attached. , FIG. 11 is a sectional view taken along line X I - X I of FIG. 9 with the diaphragm attached. 10...Vibration isolator 12...Outer tube 14...Inner tube 18...Body rubber 26...Diaphragm 34...Sub-liquid chamber 36...Main liquid chamber 1o...Vibration isolation Device 12...Outer cylinder 26...Diaphragm 34...Sub-liquid chamber 36...Main chamber Fig. 3 1yo

Claims (1)

[Claims] (1) An elastic body is spanned between an inner cylinder and an outer cylinder that are connected to the vibration generating part and the vibration receiving part, respectively, and a first liquid chamber and a second liquid chamber are provided on opposite sides of each other via the inner cylinder. A vibration isolating device in which a liquid chamber of the first liquid chamber is communicated through a restriction passage, wherein an elastic membrane, which is one of the members constituting the first liquid chamber, is manufactured separately from the elastic body, and a surrounding area is provided. A vibration isolating device characterized in that the liquid chamber is sealed by being brought into close contact with the elastic body.