JPH0449413Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a sealing device for sealing between two relatively rotating members in, for example, a compressor used in an automobile cooling system.

(Prior Art) Conventional sealing devices of this type include, for example, as shown in FIG. It is constructed in combination with a seal ring 101 to improve durability and sealing performance. In this conventional example, each member of the first seal ring 100, second seal ring 101, backup spring 102 and dust lip 103 is assembled in order from the sealed fluid side, and the outer periphery of each member is made of a metal outer cylinder. 1
04, and one end of the outer cylinder 104 was caulked and assembled. Further, a rubber portion 105 was provided on the outer periphery of the first seal ring 101 in order to improve the sealing performance between the first seal ring 101 and the outer cylinder 104.

(Problems to be Solved by the Invention) However, in the case of such a conventional example, if the caulking during assembly is too weak, the sealing performance between the first seal ring 100 and the outer cylinder 104 deteriorates. Product reliability deteriorates. For this reason, it is necessary to strengthen the caulking stop, but this will increase the strain that occurs in the outer peripheral rubber portion 105 of the first seal ring 100 compressed by the caulking portion 106 of the outer cylinder 104, causing premature deterioration of the rubber. There was a problem in that cracks were likely to form at the lever part, leading to a decrease in durability.

The present invention was developed in order to solve the problems of the prior art described above, and its purpose is to achieve high reliability and durability by using a method that does not use caulking, that is, by fitting and assembling. Our goal is to provide a sealing device with a wide range of features.

(Means for Solving the Problems) In order to achieve the above object, in the sealing device according to the present invention, a first seal ring made of a rubber-like elastic material on the sealing fluid side that seals between the housing and the rotating shaft, and a resin A metal reinforcing ring is interposed between the reinforcing ring and the second seal ring, and a back-up spring is fitted to the inner periphery of the reinforcing ring on the atmospheric side of the second seal ring. Then, the second seal ring was sandwiched between the reinforcing ring and the back-up spring, and the outer periphery of the reinforcing ring was fitted onto the inner periphery of the first seal ring for assembly.

(Function) The second seal ring is held between the reinforcing ring interposed between the first seal ring and the second seal ring, and the back spring fitted to the reinforcing ring, so that the second seal ring is reinforced. The outer periphery of the ring is fitted to the inner periphery of the first seal ring for assembly.

The present invention will be described below with reference to the illustrated embodiment.
In the drawings, 1 shows the entire sealing device, which is roughly composed of a first seal ring 2 made of a rubber-like elastic material on the sealing fluid side, and a second seal ring 3 made of a resin.
and a backup ring 4. That is, the first seal ring 2 is formed by baking a rubber-like elastic body onto an annular core metal 21, and is provided with a seal lip 23 extending at an angle toward the sealing fluid F on the inner diameter side of a cylindrical outer circumferential portion 22 which extends axially and is fitted into the inner periphery of the housing 5, and which contacts the surface of the rotating shaft 6 to form a seal portion. An outer lip 24 is provided on the sealing fluid F side edge of the outer circumferential portion 22, which is on the sealing fluid side and extends radially outward to make sealing contact with the inner periphery of the housing 5. Furthermore, an annular protrusion 25 is provided on the atmosphere side surface of the base end of the seal lip 23, which is pressed against the second seal ring 3 to seal the gap between the first and second seal rings 2, 3.

On the other hand, the second seal ring 3 is formed in an annular shape from a resin material such as tetrafluoroethylene resin, and its inner diameter side extends with an inclination toward the sealing fluid side with respect to the rotating shaft 6, and the tip of the lip is in sealing contact with the rotating shaft 6. This constitutes a seal lip 31 that forms a seal portion.
This seal lip 31 is connected to the first seal ring 2.
The first seal ring 2 extends along the side surface of the seal lip 23 facing the atmosphere, and backs up the seal lip 23 of the first seal ring 2 when pressure is received.

The first seal ring 2 and the second seal ring 3
A reinforcing ring 7 made of metal is interposed between the two.
This reinforcing ring 7 includes a cylindrical part 71 that extends in the axial direction and whose outer periphery is fitted into the inner periphery of the outer periphery 22 of the first seal ring 2, and a radial radius from the sealed fluid side and atmospheric side ends of this cylindrical part 71. It consists of flange portions 72 and 73 extending inward in the direction, and has a U-shaped cross section. The reinforcing ring 7 is press-fitted into the outer peripheral part 22, and the frictional force causes the reinforcing ring 7 and the second seal ring 3 to
Relative rotation with the The contact surface between the reinforcing ring 7 and the outer peripheral portion 22 may be provided with serrations or the like to prevent rotation.

Furthermore, on the atmospheric side of the second seal ring 3,
A metal backup spring 4 is press-fitted into the inner periphery of the cylindrical portion 71 of the reinforcing ring 7. This back-up spring 4 has a cylindrical portion 4 fitted into the reinforcing ring 7.
1 and a flange portion 42 extending radially inward from the sealed fluid side end of the cylindrical portion 41, and has a substantially cross section L.
It is shaped like a letter. The radially outer end of the second seal ring 3 is held between the flange portion 72 of the reinforcing ring 7 and the flange portion 42 of the backup spring 4. The inner diameter end of the back-up ring 4 is tapered to follow the slope of the seal lip 31 of the second seal ring 3 made of resin, and this tapered portion 43 allows the bent portion 32 at the base end of the seal lip 31 to be tapered. The second seal ring 3 is held so that the contact angle between the tip of the lip 31 of the second seal ring 3 and the rotary shaft 6 is maintained at a predetermined angle.

Further, a rubber-like elastic body is baked on the atmosphere-side side surface of the backup spring 4, and extends radially inward toward the atmosphere side on the inner periphery so that the tip of the lip is in sealing contact with the surface of the rotating shaft 6. A dust strip 8 is provided which forms a seal.

Furthermore, the flange portion 72 of the reinforcing ring 7 on the sealed fluid side is provided with an arbitrary number of protrusions 10 that bite into the side surface of the second seal ring 3, as shown in an enlarged view in FIG. In this embodiment, a plurality of projections 10 are equally spaced in the circumferential direction of the second seal ring 3, and the projections 10 are formed by recessing a portion of the inner edge of the flange portion 72 in a linear shape in the radial direction. has been
The protrusion width of the protrusion 10 is greatest at the inner end of the flange portion 72 and becomes wedge-shaped, gradually decreasing toward the outer end. Of course, the shape of the protrusion 10 may be any shape that bites into the second seal ring 3, and is not limited to a wedge shape.

Further, an annular protrusion 74 for preventing the second seal ring 3 from coming off is provided on the outer periphery of the cylindrical portion 71 of the reinforcing ring 7, and an annular protrusion 74 for preventing the second seal ring 3 from falling off is provided on the outer periphery of the cylindrical portion 71 of the reinforcing ring 7.
The second seal ring 3 bites into the inner circumferential surface of the second seal ring 3 to prevent the second seal ring 3 from coming off.

In the case of the sealing device having the above structure, the sealing device 1 is assembled by first opening the flange portion 73 of the reinforcing ring 7 on the atmosphere side as shown in FIG. A second seal ring 3 made of resin is fitted to the flange portion 42 of the back-up spring 4 and a flange portion 72 of the reinforcing ring 7. Clamp them and assemble them together by caulking the atmosphere side flange portion 73 in the direction of the arrow. Due to this caulking force, one ring of protrusions provided on the flange portion 72 of the reinforcing ring 7 bites into the side surface of the second seal ring 3 on the sealed fluid side. With the second seal ring 3 and backup spring 4 integrally assembled to the reinforcing ring 7 in this manner, the assembly is completed by fitting the reinforcing ring 7 into the inner circumference of the outer circumferential portion 22 of the first seal ring 2.

When the sealing device 1 is used, each seal lip 2 of the first and second seal rings 2 and 3 is
The tip ends of the lips 3 and 31 are in sealing contact with the surface of the rotating shaft 6 to prevent leakage of the sealing fluid F. Further, the outer periphery 22 of the first seal ring 2 fitted to the inner periphery of the housing 5 has a rubber-like elastic body coated on the outer periphery of the core metal 21, and the outer periphery is in sealing contact with the inner periphery of the housing 5. The sealing fluid is prevented from leaking from the fitting part with the inner periphery. Since there is no crimped portion on the outer periphery of the sealing device 1 fitted to the inner periphery of the housing 5, unlike the conventional sealing device, there is no distortion due to crimping, and good sealing performance can be maintained over a long period of time. Furthermore, in this embodiment, since the outer lip 24 is provided at the end of the outer circumferential portion 22 on the sealed fluid side, the sealing performance of the fitting portion with the inner circumference of the housing 5 can be further improved.

Further, the second seal ring 3 is firmly fixed by a protrusion 10 protruding from the flange portion 72 on the sealed fluid side of the reinforcing ring 7, and prevents the second seal ring 3 from rotating when the sealing device 1 is in use. Ru. In this embodiment, since the protrusions 10 are arranged radially in the radial direction orthogonal to the circumferential direction, the anti-rotation effect is large. In addition, since the protrusion 10 is shaped like a wedge and the protrusion width increases radially inward,
It is also possible to effectively prevent the second seal ring 3 from shifting inward in the radial direction.

In the above embodiment, the projection 10 is provided on the flange portion 72 of the reinforcing ring 7, but the projection 10 is not limited to the flange portion 72, but may be provided on the inner periphery of the cylindrical portion 71 where the outer peripheral surface of the second seal ring 3 comes into contact. . Further, the protrusion 10 may be provided not only on the reinforcing ring 7 but also on the backup spring 4, or may be provided on both.

Furthermore, in this embodiment, the second seal ring 3 and the backup spring 4 are assembled into one body by caulking the sealed fluid side end of the reinforcing ring 7, but it is not necessary to assemble them by caulking, and the backup spring 4 is reinforced. The second seal ring 3 may be press-fitted into the ring 7 and held between the back-up spring 4 and the reinforcing ring 7 using only the fitting force. Of course, the backup spring 4 and the second seal ring 3 can be firmly fixed by caulking and assembling them as in this embodiment.

Further, in this embodiment, the core metal 21 and the reinforcing ring 7 of the first seal ring 2 are constructed as separate members, but the core metal 21 is used as a reinforcing ring to create a structure between the core metal 21 and the back-up spring 4. The second seal ring 3 may be sandwiched.

(Effects of the invention) The present invention consists of the above-mentioned structure and operation, and instead of assembling the first and second seal rings by caulking as in the past, the invention is made by intervening between the first seal ring and the second seal ring. A second seal ring made of resin is held between a reinforcing ring and a back-up spring fitted to the reinforcing ring,
Since the outer periphery of the reinforcing ring is assembled by fitting into the inner periphery of the first seal ring, there is no variation in sealing performance on the housing side, and reliability can be improved. Further, since there is no distortion of the rubber-like elastic body of the first seal ring due to caulking as in the conventional case, cracks and the like due to deterioration of the material are less likely to occur, and durability can be improved.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a main part of a sealing device according to an embodiment of the present invention, FIG. 2 is a perspective view of a main part of a reinforcing ring of the device of FIG. 1, and FIG. A cutaway perspective view showing a state in which two seal rings are clamped and assembled between a back-up spring and a reinforcing ring, FIG. 4 is a vertical cross-sectional view of a main part showing the assembled state of the device in FIG. 1, and FIG. 5 is a conventional FIG. 3 is a vertical cross-sectional view of the main parts of the sealing device. Explanation of symbols, 1... Sealing device, 2... First seal ring, 21... Core bar, 22... Outer circumference, 23
... Seal lip, 24 ... Outer lip, 3
...Second seal ring, 31...Seal lip,
32...Bending portion, 4...Backup spring, 4
DESCRIPTION OF SYMBOLS 1... Cylindrical part, 42... Flange part, 5... Housing, 6... Rotating shaft, 7... Reinforcement ring, 71...
Cylindrical part, 72, 73... flange part, 74... protrusion, 8... dust strip, 10... protrusion.

Claims (1)

[Scope of utility model registration request] A metal reinforcing ring is interposed between the first seal ring made of rubber-like elastic material on the sealed fluid side and the second seal ring made of resin, which seals between the housing and the rotating shaft, and the second seal ring is placed on the atmosphere side of the second seal ring. A back-up spring is fitted to the inner periphery of the reinforcing ring, a second seal ring is held between the reinforcing ring and the back-up spring, and the second seal ring is held between the back-up spring. A sealing device characterized in that the outer periphery of the reinforcing ring is assembled by fitting into the inner periphery of the first seal ring.