JP2861707B2 - Anti-vibration rubber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-vibration rubber comprising a main rubber portion and a mechanically bonded portion which is vulcanized and bonded to the main rubber portion. In particular, anti-vibration rubber that requires a high degree of corrosion resistance between the mechanical coupling part made of metal and the main body rubber part, such as the engine mount of an automobile that is easily damaged by salt when traveling on the coast or on snowy roads This is a preferred invention. As used herein, the term “corrosion-resistant adhesiveness” means the adhesive durability between a rubber portion and a mechanically bonded portion under a metal corrosion atmosphere.

Here, a liquid seal engine mount will be mainly described as an example of a vibration-proof rubber, but the present invention is also applicable to other vibration-proof rubbers, for example, an engine mount, a strut mount, a bumper rubber, a bush rubber and the like. It is possible.

[0003] In the present specification, "parts" and "%" are by weight unless otherwise specified.

[0004]

2. Description of the Related Art FIG. 1 shows an example of a conventional liquid ring engine mount.

A partition plate 15 having a conductive groove 13 and a diaphragm 17 are attached to a lower mounting plate portion (cap) 19 in a cavity C for an upper liquid chamber formed in the lower central portion of the main rubber portion 11. Assemble with Here, the upper mounting plate portion 21 and the cylindrical main body insert portion 23 are integrated with the main rubber portion 11 by vulcanization bonding. And
The partition plate 15 and the diaphragm 17 are connected to each flange 1
5a and 17a are the engaging step portions 23 of the main body insert portion 23.
a and the upper liquid sealing chamber 2 above and below the partition plate 15, respectively.
5 and a lower liquid sealing chamber 27 are formed. The upper and lower mounting plate portions 21 and 19 are respectively provided with mounting bolts 29 and 31.
Is provided. Further, a stopper metal fitting 33 that interferes with the upper mounting plate 19 when assembled to the engine is mounted on the upper mounting plate 21. In addition, each liquid sealing chamber 25, 2
7 usually contains a glycol-based fluid.

[0006]

However, in the case of the engine mount having the above-described structure, the mechanical coupling portions such as the upper and lower mounting plate portions 21 and 19 and the main body insert portion 25 are usually iron-based from the viewpoint of strength. Since it is formed by pressing from a sheet metal or by casting from an iron-based casting, each part needs to be subjected to rust-proofing treatment such as galvanizing and painting, and the weight has also increased.

[0007] For this reason, it has been considered and proposed that all or a part of the parts of the mechanical joint be formed by die casting of an Al alloy which is lighter than an iron-based material (Japanese Utility Model Laid-Open No. 21348/1990). etc). However, the ADC 12 (Al-Si-
It has been considered difficult to satisfy the characteristics required for an engine mount in terms of corrosion resistance with a copper alloy) (see Tables 1 and 2).

[0008] Therefore, it is necessary to perform rust-proofing treatment such as galvanizing and painting on the parts of the mechanical joint.

In view of the above, the present invention relates to a vibration damping rubber which is a mechanical coupling portion which is vulcanized and bonded to the main rubber portion, and the mechanical coupling portion formed by Al die casting has An object of the present invention is to provide an anti-vibration rubber that does not require rust treatment.

[0010]

Means for Solving the Problems In order to solve the above-mentioned problems, the inventors of the present invention have made an effort to develop an Al-Mg-based die-casting Al alloy having a specific composition while mechanically developing. The inventors have found that in addition to the strength, the corrosion-resistant adhesiveness satisfies the required characteristics of the vibration-proof rubber, and have reached the present invention having the following constitution.

[0011] In the vibration isolating rubber serving as a main body rubber portion and a mechanical connection portion which can be vulcanized and bonded to the main body rubber portion, all or a part of the mechanical connection portion is formed of an Al alloy die-cast, However, as an essential component other than Al, Mg: 3.
0 to 5.0%, Mn: 0.2 to 0.6%, Si: 0.5
~ 1.0%, Be: 0.002-0.004%, characterized by being an Al-Mg type.

[0012]

An embodiment of the present invention will be described below in detail with reference to FIG.

(1) A partition plate 45 in which a conductive groove 43 is formed and a diaphragm 47 are attached to a lower mounting block (cap) in a cavity C for an upper liquid chamber formed in a lower central portion of a lower portion of the main body rubber portion 41. ) 49. here,
The upper mounting block 51 and the main body assert portion 53 are integrated with the main body rubber portion 41 by vulcanization bonding. The partition plate 45 and the diaphragm 47 have their respective flange portions 45a, 47a sandwiched between the engaging step portion 53a of the main body insert portion 53 and the receiving step portion 49a of the lower mounting block 49. An upper liquid sealing chamber 55 and a lower liquid sealing chamber 57 are formed above and below, respectively. The upper and lower mounting blocks 51, 49 are screwed with mounting stud bolts 59, 61, respectively. Further, the upper mounting block 51 has an anti-vibration rubber main body (the upper mounting block 51 + the main body rubber portion 41 + the main body insert portion 53).
The lower mounting block 49 is engaged with and integrated with the lower mounting block 49, and a stopper / fitting bracket 63 that interferes with the upper mounting block 49 when mounted on the engine is mounted. Up to this point, the basic configuration is similar to the above conventional example.

(2) In the above embodiment, in the present embodiment, the upper mounting block 51 and the lower mounting block 49, which are a part of the mechanical joint requiring high strength, are formed of an Al alloy die-cast. The upper mounting block 51
From the viewpoint of vulcanization adhesive bonding with the main rubber portion 41, the shape is uneven.

An Al alloy as a die-casting material contains Mg: 3.0 to 5.0 as an essential component in addition to Al.
%, Mn: 0.2 to 0.6%, Si: 0.5 to 1.0
%, Be: 0.002 to 0.004%, containing Al
-Mg-based. This Al alloy usually desirably has a low impurity content, but contains Fe, Cu, Zn, Ni and the like in a range of less than 1% (see Table 1). The actions of the above essential components are presumed to be as follows.

Mg forms a solid solution with Al and has an effect of increasing mechanical strength without deteriorating corrosion resistance. If it is less than 3.0%, problems tend to occur in mechanical strength, and if it exceeds 5.0%, problems tend to occur in fluidity (die-casting properties).

Like Mn, Mn also has a function of increasing the mechanical strength by forming a solid solution in Al, but here, the addition of a small amount has an effect of preventing the occurrence of stress corrosion.
If it is less than 0.2%, it is difficult to exert the effect of preventing the occurrence of stress corrosion,
On the other hand, if it exceeds 0.6%, a problem tends to occur relatively in fluidity (die-casting property).

Si has an effect of imparting fluidity (die-casting property) to the alloy material. If it is less than 0.5%, it is difficult to secure the die-casting property, and if it exceeds 1.0%, the corrosion resistance and the mechanical strength are likely to be adversely affected.

Be has an antioxidant effect when added in a very small amount, and has an effect of improving corrosion resistance without adversely affecting mechanical strength and the like. If the content of Be is less than 0.002%, the effect of adding Be is unlikely to be exerted. If the content of Be exceeds 0.004%, the effect of addition is not increased much.

(3) Then, the vibration isolating rubber main body sets the upper mounting block 49 and the main body insert portion 53 in a product cavity of a molding die (not shown), and injects the vibration isolating rubber material into the cavity. And mold. As a molding material for the main rubber portion, natural rubber having good vibration damping properties or ethylene propylene rubber having good heat resistance is used.

At this time, the upper mounting block 49 is subjected to a primer treatment after roughening treatment by sand blasting or the like as in the prior art. As the primer, a phenol-based primer or the like can be suitably used.

The main body insert 53, which is another mechanical connection, does not require large mechanical strength.
In the illustrated example, it is formed of a rough molded body of inorganic fiber reinforced plastic, but may be formed of the Al alloy material used for the upper mounting block.

Also, the stopper / assembly fitting 63 is
Similar to the conventional example, it is made of sheet metal, but it may be formed of the aluminum die-casting material used in the present invention.

(4) Physical properties tests were performed on the molded articles (test pieces) obtained by die-casting with the Al alloy materials having the respective compositions shown in Table 1 for the respective items shown in Table 2, and the results are shown in Table 2. . The method of the physical property test was performed by the following methods.

Mechanical strength: Using a No. 4 test piece of JIS Z 2201, the tensile strength was measured and evaluated according to the method of JIS Z 2241.

Corrosion resistance test: A pair of die-cast molded bodies (25
(× 35 × 3 mmt), a cylindrical rubber molded part having a length of φ12 mm × 10 mm was integrally molded by vulcanization bonding (vulcanization conditions: 150 ° C. × 5 minutes) to prepare a test piece. About the test piece,
Keep the rubber molded part stretched by 20% to JIS Z2371
A salt water spray test was performed according to the method described above, and the time until the rubber molded portion was peeled off from the die-cast molded body was measured and evaluated.

From Table 2, it can be seen that the Al-Mg-
It can be seen that the Si-based alloys (Examples 1 and 2) not only have high mechanical strength but also good corrosion resistance. On the other hand, the ADC 12 has no problem in mechanical strength, but has a problem in corrosion resistance. ADC6
Indicates that there is no problem in corrosion resistance, but there is a problem in mechanical strength.

[0028]

[Table 1]

[0029]

[Table 2]

[0030]

The vibration-insulating rubber according to the present invention is a vibration-insulating rubber which is a main body rubber part and a mechanical connection part which can be vulcanized and adhered to the main body rubber part. To
The following operations and effects can be obtained by forming with the Al alloy die-casting having the specific composition described above.

The die-casting material of the Al alloy die-casting which forms all or a part of the mechanical joint of the present invention has sufficiently high mechanical strength and high corrosion resistance.

Therefore, it is not necessary to perform a rust prevention treatment on the mechanical joint formed by die casting. Therefore, the man-hour and cost for manufacturing the vibration-proof rubber can be reduced as a whole.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a conventional example of a liquid-sealed engine mount (anti-vibration rubber).

FIG. 2 is a cross-sectional view showing one embodiment of a liquid ring engine mount to which the present invention is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Main body rubber part 21 Upper mounting plate part (mechanical coupling part) 23 Main body insert part (mechanical coupling part) 41 Main body rubber part 45 Partition plate 47 Diaphragm 49 Lower mounting block (mechanical coupling part) 51 Upper mounting block (machine) 53) Main body insert (mechanical connection)

Continuation of the front page (56) References JP-A-64-58823 (JP, A) JP-A-4-321823 (JP, A) JP-A-5-196077 (JP, A) JP-A-2-21348 (JP, A) , U) Jpn. 4-109608 (JP, U) (58) Fields surveyed (Int. Cl. ⁶ , DB name) F16F 13/00 F16F 1/36

Claims (1)

(57) [Claims] 1. An anti-vibration rubber comprising a main body rubber portion and a mechanical connection portion vulcanized and bonded to the main body rubber portion, wherein all or a part of the mechanical connection portion is formed by Al alloy die casting. The Al alloy is an essential component other than Al: Mg: 3.0 to 5.0%, Mn: 0.2 to 0.6%, Si: 0.5 to 1.0%, Be: 0.002 An anti-vibration rubber, which is an Al-Mg-based material containing 0.004% to 0.004%.