JPH0573365U - Side lip base shape - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] To provide a side lip that can obtain an optimum sliding pressure that is not confused by fluctuations in the contact pressure of the lip and can greatly extend its life. [Arrangement] It is characterized in that the rounded portions R1 and R2 are provided at two base portions of the side lip 1 made of an elastic body, and the base portions are made thinner than the front portion.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sealing device that is mounted between members that rotate with respect to each other and seals the inside and the outside between the members, and more particularly, to improving the shape of a side lip shape of the sealing device.

[0002]

[Prior Art]

 Conventionally, the side lip shape of the seal mounted on the rotating portion is often extended from the base portion in the axial direction while gradually tapering or maintaining the same thickness and forming a sharp lip at the tip thereof. In this side lip structure, the tapered portion is elastically deformed to adjust the contact pressure in the axial direction and maintain the contact to ensure long-term sealing.

When an example of such a structure is shown in the drawing, a lip structure as shown in Japanese Patent Application Laid-Open No. 57-103930 in FIG. 2 can be seen. Shown here are a side lip (1a) extending in the axial direction while maintaining substantially the same thickness, and a radial lip (2) that gradually taper, and the side lip (1a) and the radial lip (1a) are shown due to the mounting structure during mounting. It can be seen that the entire Allip (2) is curved and deformed by the contact pressure.

[0004]

[Problems to be solved by the device]

 However, in the case of a structure extending from the base of the side lip (1a) while keeping the same thickness in the axial direction, the entire side lip (1a) is largely deformed to receive the contact pressure, as described above. Although a good cushioning effect can be expected, the contact shape of the tip of the side lip (1a) greatly changes the contact state. That is, if excessive contact pressure is applied and the tightening margin of the lip is increased, the size of the side lip (1a) is increased, and the tip of the contact lip is set at a gentle angle with respect to the contact surface. Increase the contact area.

Naturally, the enlargement of the contact area not only causes an excessive sliding torque to be exerted on each part of the engine but also shortens the lip life. On the contrary, when only a small contact pressure is applied to the side lip (1a), the elastic repulsive force caused by the bending is not obtained instead of the large bending, and the side lip (1a) is suitable for sealing. There is a drawback that the sliding pressure cannot be obtained. The present invention eliminates many of these drawbacks, and aims to provide a side lip capable of obtaining an optimum sliding pressure that is not disturbed by fluctuations in the contact pressure of the lip and greatly extending its life.

[0006]

[Means for Solving the Problems]

 The present invention will be described with reference to the drawings. As shown in FIG. 1, the side lip (1) of the seal for sealing the rotating portion is in contact with the axial direction and has a base shape. Rs (R1) (R2) opposite to each other are provided on the inner diameter side and the outer shape side of the base, and the wall thickness of the side lip base is minimized in the vicinity of the R (R1) (R2). The dimension of () is 1.5 times or more and 1.0 times or more of the minimum wall thickness, and the radius (R2) is 1.5 times or less.

[0007]

[Action]

 The present invention has the above-described structure and has the following excellent effects. That is, since the respective dimensions and related actions specified in the present invention have the minimum wall thickness due to the inner side radius (R1) and the outer side radius (R2) which are opposite to each other at the base of the side lip (1), The bending start point of the lip (1) is determined at the minimum wall thickness portion regardless of the interference, and if this bending start point is kept constant, the side lip (1) with sufficient thickness rigidity at the end of the lip (1) undergoes large deformation. The tip of the contact is made to contact accurately without keeping the area of the contact portion constant. Therefore, any change in contact load is taken by the deforming base and has no effect on its lip contact.

Further, by setting the dimensions of the radiuses (R1) and (R2) to be 1.5 times or less and 1.0 times or more of the minimum wall thickness, the shape to be reliably deformed is determined and the deformation is performed. The points can be fixed in place and provide a stable contact sliding of the side lip (1).

[0009]

【Example】

 To implement the present invention, in FIG. 1, the radiuses to be provided are configured with radiuses (R1) and (R2) having different radii, but even if they are the same size, or the arrangement size opposite to that of FIG. It is also possible to combine these arrangements with each other, and this combination arrangement is important because the degree of bending of the entire side lip (1) can be controlled to some extent by the size of the radius. Table 1 shows a comparison of changes in contact load between the present invention and the conventional side lip.

Table 1

[0011]

[Effect of the device]

 According to the present invention, by defining the base portion of the side lip (1) as the minimum wall thickness and finely defining each portion in the vicinity thereof, the bending start point of the side lip (1) becomes constant, and therefore, there is no relation to the interference. An appropriate lip contact load can be obtained, and the seal shape that does not change the load greatly reduces the seal torque as compared with the conventional lip shape, and provides stable sealing performance.

[0012]

[Brief description of drawings]

FIG. 1 is an enlarged sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing a lip shape of a sealing device without using the present invention.

[0013]

[Explanation of symbols]

 1 side lip R1 are R2 are

Claims (1)

[Scope of utility model registration request] 1. A base shape of a side lip (1) in axial contact with a seal for sealing a rotating portion, wherein a radius (R1) (on the inner diameter side and the outer shape side of the base portion of the side lip (1) ( R2) is provided, and the wall thickness of the side lip base is minimized in the vicinity of the radius (R1) (R2), and the dimension of the radius (R1) (R2) is 1.5 times or less the minimum thickness. The base shape of the side lip is characterized by being 1.0 times or more and the radius (R2) dimension being 1.5 times or less.