JPH0723659Y2 - Lip seal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an improvement of a lip-type seal for sealing the circumference of a rotating shaft.

[Conventional technology]

Conventionally, there is a lip type seal as shown in FIG. 3 as a shaft sealing device used in, for example, a car cooler compressor.

This lip-type seal includes a rubber-made lip member 2 on the sealed space A side in the compressor, a synthetic resin (PTFE or the like) lip member 4 on the anti-sealed space B (atmosphere) side, and the synthetic resin lip member 4 The metal backup ring 6 and the pull ring 8 on the side opposite to the sealed space B are provided, and the outer diameter portion of each of these parts is formed on the inner circumference of the metal cylindrical case 10 by bending at one end of the cylindrical case 10. O-ring mounting groove 10a,
It has a structure in which it is sandwiched between a caulking portion 10b formed by bending the entire other end into a brim shape, and an O-ring 12 attached to an O-ring attaching groove portion 10a of the tubular case 10 is interposed. The housing 14 is airtightly mounted on the inner peripheral surface of the housing 14 and is fixed between the step portion 14a of the inner peripheral surface and the snap ring 16 fitted in the annular groove of the inner peripheral surface to form the sealed space A. The inner diameter sliding surfaces 2a and 4a of both lip members 2 and 4 extending toward the side are in sliding contact with the outer peripheral surface of the shaft 18 inserted into the housing 14, and the refrigerant and the refrigerating machine oil in the sealed space A leak to the atmosphere B side. Is to prevent.

[Problems to be solved by the device]

In this type of lip-type seal, due to pressure fluctuations in the sealed space A, there is a situation in which the step 14a of the housing 14 and the snap ring 16 move unstablely or the snap ring 16 cannot be fitted. In order to prevent this, it is necessary to strictly regulate the axial dimension L of the barrel lock case 10 to about 0.2 at the intersection.

However, according to the above-described conventional structure, the O-ring mounting groove portion 10a and the crimp portion 10b are used to form the lip members and other components 2, 4,
The dimension l of the sandwiched portion with respect to 6, 8 is the size of each of these parts 2, 4, 6, 8
The cylindrical case is greatly affected by variations in the dimensions of
In practice, it was extremely difficult to set the axial dimension L of 10 within the tolerance range of 0.2.

In view of the above, the lip-type seal of the present invention has been made in view of the above circumstances, and has an object to accurately regulate the axial dimension of the cylindrical case that is positioned and fixed to the inner circumference of the housing so as to be in a stable mounted state. It is a thing.

[Means for Solving the Problems]

In order to solve the above problems, in the lip-type seal according to the present invention, an O-ring mounting groove is formed by bending at one end of a metal cylindrical case, and a plurality of axially protruding positioning members are provided at the other end of the case. An edge and a plurality of claw portions punched and bent toward the inner diameter side at positions appropriately retracted from the positioning edge to the O-ring mounting groove side are alternately formed in the circumferential direction, and are arranged on the inner circumference of the cylindrical case. The outer diameter portions of the lip member and the backup ring and pull ring on the side opposite to the sealed space of the lip member are sandwiched between the O-ring mounting groove portion and the claw portion.

[Action]

According to the present invention, the axial dimension of the tubular case is guaranteed by the distance from one end having the O-ring mounting groove to the positioning edge at the other end, and the lip member, the backup ring, and the pull ring are O-shaped. Since the plurality of claws sandwiched between the ring mounting groove and the ring mounting groove are at positions retracted from the positioning edges, the tolerance of the bending position of the claws due to the dimensional variation of each component is a cylindrical case. Has no effect on the axial dimension of.

〔Example〕

The present invention will be described below with reference to an embodiment shown in FIGS. 1 and 2. The same parts as those of the conventional structure described above are designated by the same reference numerals and the description thereof will be omitted.

In the lip-type seal of this embodiment, the outer diameters of the rubber-made lip member 2, the synthetic resin lip member 4, the metal backup ring 6 and the pull ring 8 are formed by bending at one end of the metal cylindrical case 10. O-ring mounting groove
10a and a claw portion 22 which is punched and bent toward the inner diameter side at a position appropriately retracted from the positioning edge 20 at the other end of the case 10 to the O-ring mounting groove portion 10a side and bent in the circumferential direction 4. It is what you wear.

According to the above configuration, when the lip members 2, 4, the backup ring 6, and the pull ring 8 are rough in thickness, the claw portion 22 for fixing the lip members also varies in the flexion position. The axial dimension L of 10 is ensured by the positioning edge 20 at the other end of the edge 10c at one end.
Therefore, it is possible to manage the axial dimension L with an accuracy within 0.2 of the intersection, regardless of the deviation of the bent position of the claw portion 22.

Needless to say, the present invention is not limited to the illustrated embodiment. For example, the positional relationship between the O-ring mounting groove portion and the other end edge portion may be opposite to that shown in the drawing, and the claw portion may be used. The size and the number of are arbitrary.

[Effect of device]

As described above, according to the lip type seal of the present invention, the lip member,
Since the positioning edge guarantees a highly accurate axial dimension of the tubular case regardless of the variation in the bending position of the claw portion due to the thickness of the backup ring and pull ring, the tubular case can be used as a stepped portion of the housing. And the snap ring can be reliably positioned and fixed to prevent instability of the lip-type seal due to pressure fluctuations in the sealed space and failure of fitting of the snap ring for fixing the lip-type seal. .

[Brief description of drawings]

FIG. 1 is a half cutaway view showing an embodiment of the present invention, FIG. 2 is a partial front view seen from the X direction of the arrow in FIG. 1, and FIG. 3 is a half cutaway view showing an example of a conventional structure. . 2,4 ...... Lip member, 6 ...... Backup ring 8 ...... Pull ring, 10 ...... Cylindrical case 10a ...... O-ring mounting groove 12 ...... O ring, 20 ...... Positioning edge, 22 ...... Claw A …… Sealed space, B …… Anti-sealed space

Claims (1)

[Scope of utility model registration request] 1. An O-ring mounting groove is bent at one end of a metal cylindrical case, and a plurality of axially projecting positioning edges are provided at the other end of the case, and the O-ring is mounted from the positioning edges. A plurality of claw portions that are punched out and bent toward the inner diameter side at positions appropriately retracted to the working groove side are alternately formed in the circumferential direction, and a lip member arranged on the inner circumference of the cylindrical case and an anti-sealing space of the lip member. A lip-type seal, wherein outer diameter portions of the backup ring and the pull ring on the side are sandwiched between the O-ring mounting groove portion and the claw portion.