JP3293074B2 - Lip type seal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lip seal provided for sealing the periphery of a rotating shaft of a refrigerator compressor such as a cooling device.

[0002]

2. Description of the Related Art As a typical conventional example of a lip-type seal for sealing the circumference of a rotating shaft of a refrigerator compressor, as shown in FIG. 3, an outer ring 10 made of metal and this outer ring 10 is used as an insert member. An elastomer lip member 20 vulcanized and molded in a partially embedded state, a synthetic resin lip member 30 abutting on the back surface of the elastomer lip member 20,
Further, there is a well-known one provided with a metal inner ring 40 for holding the back surface of the synthetic resin lip member 30. Outer ring 10
Is covered with a crimping portion 23 made of an elastomer formed continuously with the outer diameter portion 22 of the elastomer lip portion 20, and the inner ring 40 is made of an elastomer lip member 2.
An outer diameter cylindrical portion 41 whose rear end is supported by the caulking portion 11 of the outer ring 10 exposed from 0, and a synthetic resin lip member 30 extending from the outer diameter cylindrical portion 41 to the inner diameter side. It has a substantially L-shaped cross section composed of the holding portion 42 abutting on the back surface.

[0003] That is, this lip-type seal is
Is press-fitted into the shaft hole 1a of the shaft sealing housing 1 via the crimping portion 23 made of an elastomer while the movement in the axial direction is regulated by the stepped portion 1b formed in the shaft hole 1a and the retaining ring 2. The head 21a formed at the tip of the inner diameter portion 21 of the elastomeric lip member 20 that curves and extends toward the inside A of the machine, which is a sealed space, slides on the outer peripheral surface of the shaft 3 inserted into the shaft hole 1a. In-flight A
A refrigerant such as CFC-12 or HFC-134a and refrigeration oil which are compressed in the atmosphere B
It prevents leakage inside. The lip member 30 made of synthetic resin has an inner diameter portion 3 which extends toward the inside A of the machine.
The front end 31a of the first lip member 20 reaches the vicinity of the head 21a from the inner peripheral side of the inner diameter portion 21 of the elastomer lip member 20, and supports the inner diameter portion 21 of the elastomer lip member 20 receiving the pressure in the machine A from the inner peripheral side. I have.

[0004] In the following description, the term "rear surface" refers to a surface facing the opposite side (atmosphere B side) of the cabin A, which is a sealed space, and the "tip" refers to the end of the cabin A side. Further, the “rear end” means an end opposite to the inside of the aircraft A.

[0005]

The following problems are pointed out in the above-mentioned conventional lip-type seal. That is,
CFC-12 or HFC-13 compressed in the cabin A
Refrigerant such as 4a swells and slightly permeates the lip member 20 made of elastomer. However, the amount of the permeated refrigerant is extremely small and is not recognized as a leak that causes a problem.
High-speed operation because the outer diameter portion 22 of the elastomer lip member 20, the outer diameter portion 32 of the synthetic resin lip member 30, and the outer diameter cylindrical portion 41 of the inner ring 40 accumulate in the gap G. When the ambient temperature of the lip-type seal becomes relatively high due to, for example, the pressure of the gap G sharply increases due to the vaporization or expansion of the refrigerant. Therefore, as shown in FIG.
Of the synthetic resin lip member 30 is moved toward the in-machine A side, and the tip 31a of the outer diameter portion 32 of the synthetic resin lip member 30 is moved inside the head 21a of the elastomer lip member 20. Since the head 21a is pushed and spread from the periphery, the close contact force of the head 21a with respect to the outer peripheral surface of the shaft 3 is reduced or the head 21a is not in contact with the outer surface, which may cause leakage.

SUMMARY OF THE INVENTION The present invention has been made under the above circumstances, and has a technical problem to be solved from an elastomer lip member to an outer ring, an outer diameter portion of the elastomer lip member, a synthetic resin. The pressure of the refrigerant permeating into the gap between the outer diameter portion of the lip member and the outer diameter cylindrical portion of the inner ring prevents leakage due to the synthetic resin lip member pushing and expanding the elastomer lip member. It is in.

[0007]

Means for Solving the Problems The technical problems described above are:
This can be effectively solved by the present invention. That is, the present invention relates to an outer ring in which a caulking portion bent to the inner diameter side is formed at the rear end, and an elastomer lip member in which the outer diameter portion is held at the tip of the outer ring and the inner diameter portion extends to the sealed space side. A synthetic resin lip having an outer diameter portion abutting against the back surface of the outer diameter portion of the elastomer lip member and an inner diameter portion extending toward the sealed space to support the inner diameter portion of the elastomer lip member from the inner circumference side. A member, an outer diameter cylindrical portion whose rear end is supported in contact with the caulking portion of the outer ring, and an inner diameter side extending from the outer diameter cylindrical portion to the inner diameter side, on the outer diameter portion rear surface of the synthetic resin lip member. A lip-type seal comprising an inner ring comprising a contact portion which is abutted, wherein an outer ring, an elastomeric lip is attached to an outer diameter cylindrical portion of the inner ring.
Outer diameter of the lip member, outer diameter of the synthetic resin lip
Open the gap surrounded by the outer cylindrical part of the ring to the anti-sealing space.
The required number of vents to be released have been opened.

[0008]

The gap surrounded by the outer ring, the outer diameter portion of the elastomer lip member, the outer diameter portion of the synthetic resin lip member, and the outer diameter cylindrical portion of the inner ring is formed by the outer diameter cylindrical portion of the inner ring. Since the refrigerant is opened to the anti-sealing space by the provided ventilation part, the refrigerant that has passed through the elastomer lip member and entered the gap is discharged through the ventilation part, and the atmosphere of the lip-shaped seal is generated by high-speed operation of the device or the like. Even when the temperature becomes relatively high, the pressure in the gap does not increase, and the pressure does not move the synthetic resin lip member so as to push the elastomer lip member.

[0009]

FIG. 1 shows a first embodiment of a lip-type seal according to the present invention. The inner ring 40 pressing the portion 32 against the outer diameter portion 22 of the elastomer lip member 20 is formed by the caulking portion 11 of the outer ring 10.
The required number of notches 4 are provided at the rear end of
3A is formed, and the notch 43 allows the outer ring 1 to be formed.
0, a gap G between the outer diameter portion 22 of the elastomer lip member 20, the outer diameter portion 32 of the synthetic resin lip member 30, and the outer diameter cylindrical portion 41 of the inner ring 40 is opened to the atmosphere B. The ventilation part 43 is formed as follows. The configuration of the other parts is almost the same as that of the lip-type seal of FIG. 3 described above, and the description thereof will be omitted.

According to this embodiment, a small amount of the refrigerant (CFC-12 or HFC-134a) that has passed through the elastomer lip member 20 from the inside of the machine A and entered the gap G evaporates and has an outer diameter of the inner ring 40. It is released into the atmosphere B through the notch 43A at the rear end of the cylindrical portion 41. As mentioned earlier,
Since the amount of the refrigerant permeated by the elastomer lip member 20 is extremely small, the discharge of the refrigerant from the notch 43A into the atmosphere B is of a level that does not pose a problem. Further, even if the ambient temperature of the lip-type seal becomes relatively high due to high-speed operation or the like, the pressure in the gap G does not increase because the gap G is opened to the atmosphere B by the notch 43A. Therefore, the lip member 30 made of synthetic resin is
Is moved as shown in FIG.
It is possible to effectively prevent a problem such as pushing 0 to open and causing leakage.

As shown in FIG. 2, a second embodiment of the present invention, the ventilation portion 43 may be formed of a small hole 43B formed in the outer cylindrical portion 41 of the inner ring 40.

The lip seals according to the first and second embodiments shown in FIGS.
Is vulcanized and formed integrally with the outer ring 10. However, in the present invention, the lip member 20 made of elastomer and the lip member 30 made of synthetic resin are sandwiched between the outer ring 10 and the pressing portion 42 of the inner ring 40. Then, the present invention can be similarly applied to a lip-type seal in which the outer ring 10 is press-fitted into the shaft hole 1a of the housing 1 via a packing such as an O-ring.

[0013]

According to the present invention, the pressure in the gap between the outer ring, the outer diameter portion of the elastomer lip member, the outer diameter portion of the synthetic resin lip member, and the outer diameter cylindrical portion of the inner ring increases. Since the pressure is not applied, the synthetic resin lip member does not move so as to push the elastomer lip member open from the outer peripheral surface of the shaft due to the pressure, thereby effectively preventing the occurrence of leakage.

[Brief description of the drawings]

FIG. 1 is a half sectional view showing a use state of a first embodiment of a lip-type seal according to the present invention, cut along a plane passing through an axis.

FIG. 2 is a half sectional view showing a use state of a lip type seal according to a second embodiment of the present invention by cutting along a plane passing through an axis.

FIG. 3 is a half sectional view showing a use state of an example of a conventional lip-type seal, cut along a plane passing through an axis.

FIG. 4 is a half cross-sectional view of the lip-type seal in which a leak has occurred, taken along a plane passing through an axis.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 3 Shaft 10 Outer ring 11 Caulking part 20 Elastomer lip member 30 Synthetic resin lip member 40 Inner ring 41 Outer diameter cylindrical part 42 Pressing part 43 Vent part

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Takeshi Yamada 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Inside Toyota Industries Corporation (72) Inventor Koichiro Oiyama 1212 Abe, Ochiai-cho, Takahashi-shi, Okayama Eagle (56) References JP-A-4-347069 (JP, A) JP-A-61-186868 (JP, U) JP-A-62-124371 (JP, U) JP-A-3-121270 (JP, U) Japanese Utility Model 3-17473 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) F16J 15/32

Claims (1)

(57) [Claims] An outer ring having a caulked portion bent at the rear end toward the inner diameter side; an elastomer lip member having an outer diameter portion held at a tip of the outer ring and an inner diameter portion extending to the sealed space side; A synthetic resin lip having an outer diameter portion abutting against the back surface of the outer diameter portion of the elastomer lip member and an inner diameter portion extending toward the sealed space to support the inner diameter portion of the elastomer lip member from the inner circumference side; A member, an outer diameter cylindrical portion whose rear end is supported in contact with the caulked portion of the outer ring, and an inner diameter side extending from the outer diameter cylindrical portion to the inner diameter side of the synthetic resin lip member. An inner ring comprising an abutting pressing portion, and an outer ring, an elastomer lip portion on an outer diameter cylindrical portion of the inner ring.
Of the outer diameter of the material, the outer diameter of the synthetic resin lip
Open the gap surrounded by the outer cylindrical part to the anti-sealing space
Lip-type seals, wherein the vent of the required number has been established that.