JPWO2015186677A1 - Sealing device - Google Patents

Abstract

A sealing device that seals foreign matter from entering an inside of a machine between a rotating member and a stationary member of an apparatus, the sealing device having a structure in which a non-rotating seal lip is slidably contacted with a seal flange on a rotating side. , Make it difficult for foreign matter such as muddy water to enter. In order to achieve this object, a sealing device that seals foreign matter from entering the machine between a rotating member and a stationary member of the equipment, and a non-rotating seal lip is slidably contacted with the rotary seal flange. In the sealing device having the structure to be made, the material of the seal lip is HNBR. Apply grease with low water resistance to the seal lip. The water wash resistance of the grease is 4 wt% or less.

Description

  The present invention is a sealing device that seals foreign matter from entering the machine between a rotating member and a stationary member of an apparatus, and has a structure in which a non-rotating seal lip is slidably contacted with a seal flange on a rotating side. The present invention relates to a sealing device provided. The sealing device of the present invention is used, for example, in the field of automobiles.

  2. Description of the Related Art Conventionally, a sealing device 101 shown in FIG. 2 is known as a sealing device (drive system / rotating oil seal) used in a drive system of a vehicle such as an automobile. The sealing device 101 includes a first seal lip 102 that seals a fluid to be sealed (such as oil) in the machine A from leaking out of the machine B, and foreign matter (such as muddy water, rainwater, or dust) from the machine B to the machine A The former first seal lip 102 is a radial lip that is slidably in close contact with the outer peripheral surface of the shaft 104, and the latter second seal lip 103 is a seal flange 105. The side lip (end surface lip) is slidably in close contact with the axial end surface.

JP-A-8-14399 (FIG. 3)

  However, the sealing device 101 shown in FIG. 2 is required to have further improved functions with respect to the following points.

  When the sealing device 101 is used in a harsh environment such as a wetland where the entire sealing device 101 is immersed in muddy water, the muddy water passes through the second seal lip 103 and enters the inter-lip space C. There is. The intruding muddy water accumulates as mud, and the mud bites into the sliding portion of the first seal lip 102, and thus the fluid to be sealed may leak.

  SUMMARY OF THE INVENTION In view of the above, the present invention is a sealing device that seals foreign matter from entering a machine between a rotating member and a stationary member of an apparatus, and a non-rotating seal lip on a rotary side seal flange. It is an object of the present invention to provide a sealing device having a structure that allows sliding contact with an external foreign object such as muddy water.

In order to solve the above problems, the present invention employs the following means.
The sealing device of the present invention is a sealing device that seals foreign matter from entering the machine between a rotating member and a stationary member of the device, and a non-rotating seal lip is slidably contacted with a rotary-side seal flange. In the sealing device having the structure, the seal lip is made of hydrogenated nitrile rubber (HNBR), and the seal lip is coated with grease having a low water resistance against washing (Claim 1).

  According to the sealing device of the present invention (Claim 1), it is possible to improve the muddy water resistance of the seal lip by making the material of the seal lip HNBR. However, when the seal lip material is HNBR in this way, squealing (abnormal noise associated with sliding) occurs when the grease applied to the seal lip is washed away by muddy water and the lip sliding part becomes poorly lubricated. There are things to do. Therefore, in order to cope with this, grease having a low water resistance against washing was applied to the seal lip. Thus, if grease with a small washing water resistance is applied to the seal lip, lubrication of the lip sliding portion is maintained even in a muddy water environment, so that the occurrence of squeal can be suppressed.

In order to achieve the above object, the present invention may further employ the following means.
In the sealing device (claim 1), the water resistance of the grease to washing is 4 wt% or less (claim 2).

  According to the sealing device of the present invention (Claim 2), since the grease with a small water washing resistance of 4 wt% or less is applied to the seal lip, the lubrication of the lip sliding portion is maintained even in a muddy water environment, Therefore, it is possible to suppress the occurrence of squeal.

  The present invention has the following effects.

  That is, in the present invention, as described above, it is possible to maintain the lubrication of the lip sliding portion even in a muddy water environment and suppress the occurrence of squeal. Therefore, the occurrence of squeal can be suppressed while improving the muddy water resistance of the seal lip.

Sectional drawing of the principal part of the sealing device which concerns on the Example of this invention. Sectional drawing of the principal part of the sealing device which concerns on a prior art example

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a cross section of a main part of a sealing device 1 according to an embodiment of the present invention. In the sealing device 1 according to this embodiment, the fluid to be sealed (oil or the like) in the machine A leaks to the outside B between the shaft (rotating member) 51 and the housing (stationary member) 52 in the drive system of the vehicle such as an automobile. The first lip seal member 11, the second lip seal member 21, and the deflector 31 are sealed so that foreign matter (such as muddy water, rainwater or dust) outside the machine B does not enter the machine A. It is comprised by the combination of.

  The first lip seal member 11 has an attachment ring 12 made of a rigid material such as metal fixed (fitted) to the opening of the shaft hole of the housing 52, and the rubber-like elastic body 13 is attached to the attachment ring 12. A seal lip 14 that is vulcanized and bonded to the outer peripheral surface of the shaft 51 by the rubber-like elastic body 13 so as to prevent leakage of a fluid to be sealed in the machine A, and the seal lip 14 The dust lip 15 that makes it difficult for foreign matter to enter the seal lip 14 by being slidably in close contact with the outer peripheral surface of the shaft 52 on the outside A side is integrally formed. The seal lip 14 is arranged with its tip part 14a facing the in-machine A side because of its function, and the dust lip 15 is arranged with its tip part 15a facing the outside of the machine because of its function.

  The mounting ring 12 has a first cylindrical portion 12a that is fixed (fitted) to the inner peripheral surface of the shaft hole opening of the housing 52, and one axial direction of the first cylindrical portion 12a (the in-machine A side). The first radial portion 12b is integrally molded from the end of the first radial direction toward the inside in the radial direction, and the second cylindrical portion is directed from the inner peripheral end of the first radial direction portion 12b to the other axial direction (the outside B side). 12c is integrally formed, and a second radial portion 12d is integrally formed radially inward from the other axial end of the second cylindrical portion 12c, and is formed at the inner peripheral end of the second radial portion 12d. The seal lip 14 and dust lip 15 are held. Further, a third radial portion 12e is integrally formed from the other axial end of the first cylindrical portion 12a outward in the radial direction, and the third radial direction portion 12e extends from the outer peripheral end to the other axial end. Three cylindrical portions 12f are integrally formed.

  The second lip seal member 21 has an attachment ring 22 made of a rigid material such as metal fixed (fitted) to the attachment ring 12 of the first lip seal member 11, and a rubber-like elastic body 23 is attached to the attachment ring 22. The rubber-like elastic body 23 forms a seal lip 24 that seals against the entry of foreign matter outside the machine B by slidably coming into contact with the seal flange 31b of the deflector 31. ing. The seal lip 24 is arranged with its tip 24a obliquely outward and radially outward from the function thereof, so that the seal lip 24 is slid onto one end face in the axial direction of the seal flange 31b. It is a side lip (end surface lip) that is closely movable.

  The mounting ring 22 has a cylindrical portion 22a that is fixed (fitted) to the inner peripheral surface of the third cylindrical portion 12f of the mounting ring 12 in the first lip seal member 11, and the axial direction of the cylindrical portion 22a A radial portion 22b is integrally formed from one end portion inward in the radial direction. The radial portion 22 b is abutted against the third radial portion 12 e of the mounting ring 12 in the first lip seal member 11.

  The deflector 31 is made of a rigid material such as metal and has a first cylindrical portion 31a that is an outer peripheral surface of the shaft 51 and is fixed (fitted) to the stepped portion 51a. The shaft of the first cylindrical portion 31a A seal flange (radial portion) 31b is integrally formed from the other end portion in the radial direction outward in the radial direction, and a second cylindrical portion 31c is integrally formed from the outer peripheral end portion of the seal flange 31b in the axial direction. . The second cylindrical portion 31c is disposed on the outer peripheral side of the third cylindrical portion 12f of the mounting ring 12 in the first lip seal member 11, and partially overlaps the third cylindrical portion 12f in the axial direction. Therefore, it functions as a cover that makes it difficult for foreign matter outside the machine B to enter the outer peripheral space D of the seal lip 24.

  In the second lip seal member 21, the seal lip 24 is molded using HNBR as a molding material.

  In addition, grease (not shown) is applied to the seal lip 24 prior to use. As this grease, grease having a low water-washing water resistance is applied. Specifically, the water-washing water resistance is 4 wt% or less. More preferably, 2 wt% or less of grease is applied.

  In the sealing device 1 having the above configuration, since the seal lip 14 of the first lip seal member 11 is slidably in close contact with the outer peripheral surface of the shaft 51, the seal target fluid in the machine A is sealed so as not to leak, and Since the seal lip 24 of the second lip seal member 21 is slidably in close contact with the seal flange 31b of the deflector 31, sealing is performed so that foreign matter outside the machine B does not enter. Further, since the seal lip 24 of the second lip seal member 21 is molded using HNBR as a molding material, the seal lip 24 has improved muddy water resistance. It is difficult to enter the inter-lip space C through the sliding portion. In addition, since the grease having a low water washing resistance is applied to the seal lip 24, it is possible to maintain the lubrication of the lip sliding portion even in a muddy water environment, thereby suppressing the occurrence of squeal.

これにより、実施例品は比較例品よりも泥水シール性が高いことを確認することができた。Since the inventors of the present application conducted a comparative test on the sealing performance against muddy water, the contents and results of the test will be described below.
1. Test sample The material of the seal lip 24 was HNBR, and the product was acrylic rubber (ACM).
2. Test Method and Results With the muddy water (water + Kanto Loam JIS 8 types) immersed in the shaft center of the sealing device, the deflector was rotated at a low speed and the time until the muddy water entered was measured. Table 1 shows the results of a relative comparison with the muddy water sealing time of the comparative product as 100.

Thereby, it was confirmed that the example product had higher muddy water sealing performance than the comparative example product.

２．試験方法および結果
試験は、シールリップ２４に各グリースを一定量塗布し、デフレクターをａ．高速回転、ｂ．低速回転、ｃ．中速回転させ、ａ〜ｃを１サイクル：２．５時間とし、各サイクル後に鳴きが発生するか確認し、鳴きが発生するまでのサイクル数を測定した。実施例品におけるサイクル数を１００として、相対比較した結果を表３に示す。

結果として、実施例品は比較例品と比較して、鳴き発生までのサイクル数が多く、鳴き抑制の効果が得られていることを確認することができた。Next, since the comparative test about the squeal suppression effect by the water-washing water resistance of a grease was conducted, the content and result of the test are demonstrated below.
1. Specimen The material of the seal lip 24 is HNBR, and the seal lip 24 is applied with a certain amount of sample 1 in Table 2 as a grease. It was.

2. Test Method and Results The test was performed by applying a certain amount of each grease to the seal lip 24 and applying a deflector a. High speed rotation, b. Low speed rotation, c. It was rotated at a medium speed, a to c were set to 1 cycle: 2.5 hours, and whether or not squeal occurred after each cycle was measured, and the number of cycles until squeal occurred was measured. Table 3 shows the results of a relative comparison with the number of cycles in the example product as 100.

As a result, compared with the comparative example product, the example product had a larger number of cycles until the occurrence of squeal, and it was confirmed that the effect of squeal suppression was obtained.

結果として、実施例品は鳴き発生前までグリースが十分残留しており、シールリップ２４の潤滑が保持されていることを確認することができた。In addition, the test was terminated in the cycle before squealing, and the amount of remaining grease was examined. Table 4 shows the results of a relative comparison of the residual amount with the amount of grease applied before the test as 100.

As a result, it was confirmed that the example product had sufficient grease remaining before the occurrence of squeal, and the lubrication of the seal lip 24 was maintained.

DESCRIPTION OF SYMBOLS 1 Sealing device 11 1st lip seal member 12,22 Mounting ring 12a, 12c, 12f, 22a, 31a, 31c Cylindrical part 12b, 12d, 12e, 22b Radial direction part 13,23 Rubber-like elastic body 14,24 Seal lip 14a, 15a, 24a Tip portion 15 Dustrip 21 Second lip seal member 31 Deflector 31b Seal flange 51 Shaft 51a Stepped portion 52 Housing A In-machine B Out-of-machine C Inter-lip space D Outer space

Claims (2)

A sealing device that seals foreign matter from entering an inside of a machine between a rotating member and a stationary member of an apparatus, the sealing device having a structure in which a non-rotating seal lip is slidably contacted with a seal flange on a rotating side. ,
The material of the seal lip is HNBR,
A sealing device characterized in that a grease having a low water resistance to washing is applied to the seal lip. The sealing device according to claim 1.
The sealing device according to claim 1, wherein the grease has a water resistance of 4 wt% or less.

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