JPH0665663U - Oil seal - Google Patents

Abstract

(57) [Summary] [Object] To provide an oil seal having a thin radial thickness by combining a substantially cylindrical fitting member and a sealing member. [Structure] A substantially cylindrical reinforcing ring (3) and a sealing lip (2)
An oil seal characterized by integrally combining a seal portion (4) in which is arranged and a fitting tubular portion (5) having a tubular shape.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a seal device which is mounted between two mutually movable members to seal the inside and the outside of the two members, and more specifically, a combined structure that improves the mountability and realizes the mounting of a narrow gap part. To improve the shape of an oil seal composed of

[0002]

[Prior art]

 2. Description of the Related Art Conventionally, a structure shown in FIG. 4 has been widely practiced as an oil seal for sealing the two relatively rotating members of this type. That is, a sealing device (B) is completed by integrally molding a sealing lip (2) made of an elastic body at the end of an L-shaped ring (6) having a tubular portion and a flange portion. With the sliding contact pressure of (2), the lubricating oil that flows out from the inside has a sealing effect.

[0003]

[Problems to be solved by the device]

 However, the above sealing device (B) cannot reduce the size of (h) beyond a certain size due to the strength constraint of the mold structure at the time of molding, and the entire thickness (H) size is naturally wide. Inevitably, therefore, there were weak points that could not be fitted in the narrow gap.

In order to solve such a problem, the main lip (2a) has an outer diameter substantially the same as that of a cylindrical retainer (8) having a flange, as in Japanese Utility Model Laid-Open No. 3-38461 shown in FIG. ) Is also devised, but the oil seal (C) has a retainer (8), which is a fitting portion, and a main lip (2a) in close proximity to each other, and is continuously integrated. The main lip (2a) is apt to be directly influenced by the mounting state of the mounting member, and has a drawback that stable sealing performance cannot be exhibited. Furthermore, the structure is inevitably wide, which limits the size and weight of the seal.

Further, in order to enhance the sealing force of the sealing device (B), it is necessary to widely provide a large contact elastic force with the contact surface of the sealing lip (2). ) Is increased or the tightening force of the garter spring (7) is strengthened to deal with it, but if the tightening force of the sealing lip (2) is strengthened, the shape during driving slides greatly. This represents a defect that the distance between the rotating member and the rotating member (1b) is extremely deteriorated. An object of the present invention is to provide an oil seal that eliminates such drawbacks, improves wearability, eliminates imperfections in mounting, and can exhibit a stable sealing force.

[0006]

[Means for Solving the Problems]

As shown in FIG. 2, the present invention is fixed to one mounting member (1a) which rotates relative to one another, and a sealing lip (2) made of an elastic material such as synthetic rubber or synthetic resin is slid on one rotating member (1b). An oil seal (A) for moving and sealing the inside and outside thereof, wherein the oil seal (A) has a tubular shape with a sealing lip (2) or a tubular shape with a small flange, as shown in FIG. It is characterized by comprising a seal portion (4) provided with a reinforcing ring (3) and a fitting tubular portion (5) having a substantially tubular shape which is press-fitted into the mounting member (1a).

Further, as shown in FIG. 2, the fitting tubular portion (5) has a tubular shape and has a substantially U-shaped cross section, and the inside of the U-shaped tubular portion (5 a) has the above-mentioned shape. The reinforcing ring (3) is fitted to integrate them, and at the same time, the end (5b) of the U-shaped cylindrical portion (5a) is brought into pressure contact with the back surface of the sealing lip (2) to form the sealing lip ( The feature is that the sliding diameter of 2) is changed.

Further, as shown in FIG. 3, an oil seal composed of the sealing lip (2) and a seal portion (4) having a reinforcing ring (3) is brought into pressure contact with the back surface of the sealing lip (2). It is also possible to adopt a structure in which the mounting member (15a) having the U-shaped end portion (15b) is directly fitted.

[0009]

[Action]

 The wooden device has the above-mentioned structure and performs the following excellent actions. That is, in the oil seal shown in FIG. 1, the seal portion (4) is formed by the sealing lip (2) and the reinforcing ring (3), and the fitting cylinder portion (5) is integrally assembled to this. Therefore, the fitting deformation stress from the mounting member (1a) is shared by the fitting cylinder portion (5), the seal portion (4) and the reinforcing ring (3), and thereby an appropriate seal holding force and an outer circumference are provided. The sealing performance is obtained.

Next, as shown in FIG. 2, a U-shaped tubular portion (5a) in which the tubular shape is folded back is formed, and the reinforcing ring (3) is fitted inside the tubular portion (5a) and the sealing lip ( When the end portion (5b) is brought into pressure contact with the back surface of 2), the sliding diameter of the sealing lip (2) is changed as indicated by the dotted line due to the diameter changing action of the end portion (5b). Since the sealing lip (2) is placed in a state where the diameter is expanded and the tightening margin of the sliding contact is reduced as compared with the normal free state, it can be smoothly and reasonably inserted into the rotating member (1b). After this mounting, the sealing lip (2) directs all the tensioning force that can be held away from the end (5b) to the rotating part (1b).

[0011]

【Example】

 In carrying out the present invention, in the drawings, only the function to be obtained without providing the fitting on the fitting tubular portion (5) or the U-shaped tubular portion (5a) has been described, but the present invention is not limited to this shape, and for example, A sliding lip that slides on the rotating member (1b) may be added to this, or a sealing band made of an elastic body may be provided at the fitting contact portion in order to further enhance the fitting and sealing force thereof ( Neither is shown).

Further, as shown in FIG. 3, a U-shaped end portion (15b) is formed on a mounting member (15a), and a sealing portion (4) having the sealing lip (2) and a reinforcing ring (3). If an oil seal consisting of and is fitted inside the U-shaped portion and the U-shaped end portion (15b) is brought into pressure contact with the rear surface of the sealing lip (2), the above-mentioned diameter changing action causes Since the sliding diameter is changed and the sealing lip (2) is placed in a state where the interference is reduced, it has a function of smoothly and reasonably being inserted into the rotating member (1b).

[0013]

[Effect of device]

 According to the present invention, as described above, the seal portion (4) or the fitting cylinder portion (5) is formed as a separate body, and the different fitting action and sealing action are effectively exerted without being affected by each. Further, the seal portion (4) can be provided with a reinforcing ring (3) made of a small piece member, which is extremely advantageous in pretreatment of the reinforcing ring (3) or molding of the seal portion (4). Therefore, the space after molding is extremely small, and by combining the seal portion (4) alone or the fitting cylinder portion (5), the thickness in the radial direction can be greatly reduced. Further, by changing the diameter of the sealing lip (2) with the mounting member (15a) having the end portion (5b) or the end portion (15b) of the U-shaped tubular portion (5a), it is extremely easy, accurate and safe. Can be worn.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an oil seal of the present invention.

FIG. 2 is a cross-sectional view showing another embodiment of the oil seal of the present invention.

FIG. 3 is a sectional view showing another embodiment of the oil seal of the present invention.
It is a side view.

FIG. 4 is a cross-sectional view showing a conventional structure without using the present invention.

FIG. 5 is a cross-sectional view showing another conventional structure not using the present invention.
It is a side view.

[Explanation of symbols]

 1a Mounting member 15a Mounting member having an end portion 1b Rotating member 2 Sealing lip 3 Reinforcing ring 4 Sealing portion 5 Fitting tubular portion 5a U-shaped tubular portion 5b End portion 15b U-shaped end portion

Claims (3)

[Scope of utility model registration request] 1. An oil seal fixed to one mounting member (1a) that rotates relative to one another, and a sealing lip (2) made of an elastic body is slid on one rotating member (1b) for sealing. The oil seal comprises a reinforcing ring (3) having a sealing lip (2) having a tubular shape or a tubular shape with a small flange.
An oil seal, comprising: a seal portion (4) in which is provided and a fitting tubular portion (5) having a substantially tubular shape that is press-fitted into the mounting member (1a). 2. The fitting tubular portion (5) has a tubular shape and has a substantially U-shaped cross section, and the U-shaped tubular portion (5) is formed.
The reinforcing ring (3) is fitted inside the a) to integrate them, and the end portion (5b) of the U-shaped tubular portion (5a) is pressed against the back surface of the sealing lip (2). An oil seal, characterized in that the sliding diameter of the sealing lip (2) is changed by contact. 3. An end portion having a U-shape for press-contacting an oil seal composed of the sealing lip (2) and a seal portion (4) having a reinforcing ring (3) with the back surface of the sealing lip (2). An oil seal directly fitted to a mounting member (15a) having 15b).