CN111895095A - seal assembly - Google Patents

Abstract

The invention relates to a sealing assembly for sealing between a first member and a second member that can rotate relatively, which is annular as a whole and includes a skeleton and a sealing part, the sealing part includes a radially inner end from the skeleton The first main sealing lip extends both axially inward and radially inward. The seal assembly also includes a second primary seal lip disposed radially spaced from the first primary seal lip, and a wiper including a first edge, a second edge, and a wiper extending generally along an axial direction of the seal assembly. A third edge extending along the axial direction, the first edge is used to securely mount the dust piece to the first member, the first primary sealing lip is configured to form a contact seal with the first member or the first edge, the second primary sealing lip is The sealing lip is configured to form a contact seal with the third edge such that the dust piece, the first main sealing lip, the second main sealing lip, and the first main sealing lip and the second main seal of the skeleton and/or the sealing portion The portion between the lips defines a seal cavity.

Description

seal assembly

technical field

The present invention relates to the field of sealing, and more particularly to a sealing assembly for use between a first member and a second member of an inner wheeldriver (IWD) that are rotatable relative to each other.

Background technique

For an electric drive hub for a vehicle, it typically includes a first member (eg, a shaft of an electric motor) and a second member (eg, a gear box) that are rotatable relative to each other, wherein the shaft of the electric motor is capable of rotating relative to each other The rotation of the gearbox, the use of a contact seal assembly between the shaft of the electric motor and the gearbox to form a sealed space between the gearbox and the seal assembly, which can prevent the oil (such as lubricating oil) inside the gearbox from entering the electric motor and at the same time prevent Dust and other impurities from the external environment enter the inside of the gearbox.

In the prior art, a sealing assembly as shown in FIG. 1 is generally used for sealing in an electric drive wheel hub, wherein the left side is the oil side and the right side is the environment side in the drawing. The sealing assembly is generally annular in shape and as shown in the partial cross-sectional view of FIG.

Specifically, the skeleton 10 is made of a hard material such as metal and includes: a skeleton axial portion 101 extending substantially along the axial direction A of the sealing assembly; a skeleton radial portion 103 extending substantially along the radial direction R of the sealing assembly ; and the skeleton connecting portion 102 as a transition between the skeleton axial portion 101 and the skeleton radial portion 103 .

On the other hand, the sealing portion 20 is attached to the skeleton 10 , especially mostly to the ends of the skeleton axial portion 101 , the skeleton connecting portion 102 and the skeleton radial portion 103 . In particular, the sealing portion 20 comprises a main sealing lip 21 extending from the radially inner end of the radial portion 103 of the skeleton to, for example, the shaft 40 of the electric motor, thereby passing through the sealing portion 20 on the upper side of the drawing, on the lower side of the drawing The main sealing lip 21 and the frame 10 form a sealing space K around the inner side of the sealing assembly. also. The main sealing lip 21 is in contact with the surface of the shaft 40 by the spring 30 in the sealing space K located on the radially outer side thereof, and the spring 30 always exerts a spring force toward the radially inner side to the main sealing lip 21, so that the main sealing lip 21 A contact seal is achieved with its wedge-shaped contact portion with the shaft 40 .

The sealing assembly having the above-mentioned structure is mainly used for the electric drive wheel hub in the automobile. For sealed systems, leakage is a particular concern. In most cases of seal failure, the resulting leakage has many adverse consequences.

SUMMARY OF THE INVENTION

The present invention is proposed based on the above-mentioned deficiencies of the prior art. The object of the present invention is to provide a sealing assembly, which can improve sealing performance and reduce leakage without additionally increasing the overall size or space requirements of the sealing assembly by making full use of the internal sealing space and adding additional sealing structures therein. possible.

In order to achieve the above purpose of the invention, the present invention can adopt the following technical solutions.

The present invention provides a sealing assembly, which is used for sealing between a first member and a second member that can rotate relatively. The sealing assembly is annular as a whole and includes a frame and a sealing portion. The second member, the seal portion includes a first main seal lip extending from the radially inner end portion of the skeleton toward the axially inner side and simultaneously toward the radially inner side. In particular, the seal assembly further includes a second main seal lip disposed radially spaced from the first main seal lip, and a dust shield including a substantially axially extending seal assembly. A first side, a second side and a third side extending substantially along the axial direction, the second side connects the first side and the third side, the first side is used to A dust piece is fixedly mounted to the first member, the first primary sealing lip is configured to form a contact seal with the first member or the first edge, and the second primary sealing lip is configured to form a contact seal with the first member or the first edge. The third edge forms a contact seal, so that the dustproof member, the first main sealing lip, the second main sealing lip, and the skeleton and/or the sealing part located in the first main sealing lip The portion between the sealing lip and the second primary sealing lip defines a seal cavity around it.

In at least one embodiment, the second primary sealing lip has a similar configuration and dimensions to the first primary sealing lip.

In at least one embodiment, a first spring is provided on the radially outer side of the first main sealing lip, and the first spring applies a spring force toward the radially inner side to the first main sealing lip. The second main sealing lip extends from the axially inner side of the skeleton radial portion of the skeleton toward the radially inner side and at the same time toward the axially inner side, wherein a second main sealing lip is provided on the radially outer side of the second main sealing lip A spring that applies a spring force toward the radially inward direction of the second main seal lip.

In at least one embodiment, the second main sealing lip has the configuration of an arcuate thin plate and extends arcuately towards the radially inner side and at the same time towards the axially inner side.

In at least one embodiment, the thickness of the second main sealing lip in the radial direction is smaller than the thickness of the first main sealing lip in the radial direction of the seal assembly.

In at least one embodiment, the radially outer side of the second main sealing lip is free from a spring exerting a spring force on it.

In at least one embodiment, the second primary sealing lip contacts the third edge with an arcuate portion having a certain length.

In at least one embodiment, the axial cross-section of the second main sealing lip as a whole has an arcuate profile that protrudes radially inward.

In at least one embodiment, a second primary sealing lip is provided at a radially intermediate position of the skeleton.

In at least one embodiment, a first primary sealing lip is in contact with the first side and the second primary sealing lip is in contact with a radially outer side of the third side.

Description of drawings

FIG. 1 is a schematic partial cross-sectional view of a prior art sealing assembly.

2 is a schematic partial cross-sectional view of a seal assembly according to a first embodiment of the present invention.

3 is a schematic partial cross-sectional view of a seal assembly according to a second embodiment of the present invention.

Description of reference numerals

10 Frame 101 Frame axial part 102 Frame connection part 103 Frame radial part 20 Seal part 21 Main sealing lip 201 First main sealing lip 202 Second main sealing lip 30 Spring 31 First spring 32 Second spring 40 Shaft 50 Dustproof The first side 52 of the piece 51 is the second side 53 and the third side A is the axial direction R and the radial direction K seals the space.

Detailed ways

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings in the description of the present invention. The overall shape of the seal assembly of the present invention is annular. Unless otherwise specified, "axial" and "radial" described in the following specific embodiments refer to the axial and radial directions of the sealing assembly, respectively. In addition, in the following specific embodiments, the axially outer side (environment side) is the right side in each drawing, and the axially inner side (sealed side/lubricant side/oil side) is the left side in each drawing; The outer side is the upper side in each drawing, and the radially inner side is the lower side in each drawing.

Several exemplary embodiments according to the present invention will be described below.

(first embodiment)

In this embodiment, as shown in FIG. 2 , the sealing assembly mainly includes a frame 10 and a sealing portion 20 , wherein the sealing portion 20 is attached to the frame 10 . The frame 10 is preferably made of a hard material such as metal, and the sealing portion 20 is preferably made of an elastic material such as rubber.

The structure of the skeleton 10 in this embodiment is basically the same as that of the skeleton 10 of the prior art sealing assembly shown in FIG. 1 . As shown in FIG. 2 , the frame 10 includes a frame axial portion 101 extending substantially along the axial direction A of the sealing assembly and a frame radial portion 103 extending substantially along the radial direction R of the sealing assembly, wherein the frame axial portion 101 For fixed mounting to the second member. Here, "substantially along the axial direction A of the seal assembly" means not absolutely parallel to the axial direction A, but with possible slight deviations. "Substantially along the radial direction R of the seal assembly" has a similar meaning.

The structure of the sealing portion 20 in this embodiment is the same as that of the sealing portion 20 of the prior art sealing assembly shown in FIG. 1 . As shown in FIG. 2 , the sealing portion 20 includes a first main sealing lip 201 extending from the radially inner end portion of the skeleton radial portion 103 toward the axially inner side while simultaneously extending toward the radially inner side. The first main sealing lip 201 can apply a spring force toward the radially inner side to the first main sealing lip 201 through the first spring 31 located on the radially outer side thereof.

In the present embodiment, in the sealed space K, a second main seal lip is preferably provided at a radially intermediate position (not necessarily at the center) of the skeleton radial portion 103 and radially spaced from the first main seal lip 201 202, the second main sealing lip 202 has a similar configuration and dimensions to the first main sealing lip 201, also extends from the axially inner side of the skeleton radial portion 103 towards the radially inner side and at the same time towards the axially inner side, and can be The second main sealing lip 202 is subjected to a spring force towards the radially inner side by the second spring 32 located radially outside thereof. The extension angle of the second main sealing lip 202 may be the same as or different from that of the first main sealing lip 201 , and the extension length of the second main sealing lip 202 may be the same or different from that of the first main sealing lip 201 . The sealing space K can be divided into two parts with similar volumes by the second main sealing lip 202 . The radial position of the second main sealing lip 202 can be changed as required.

In particular, in the present embodiment, there is also provided a dustproof member 50 made of, for example, a metal plate, which is annular in cross-section (axial cross-section) of a substantially U-shape and includes a first side 51, a second side 52 and the third side 53. As shown in FIG. 2 , the cross section of the dustproof member 50 is a side U-shaped, the length directions of the first side 51 and the third side 53 that are approximately parallel to each other are parallel or approximately parallel to the axial direction A, and the length direction of the second side 52 The length direction is parallel to the radial direction R, wherein the dustproof member 50 is assembled on the shaft 40 by means of an interference fit on the first side 51, so that the dustproof member 50 is connected to the shaft due to the large contact force between the dustproof member 50 and the shaft 40. 40 rotate together, wherein a sealing effect is achieved between the dustproof piece 50 and the shaft 40 .

The radially inwardly directed spring force exerted by the first spring 31 on the first main sealing lip 31 causes the wedge-shaped contact portion of the first main sealing lip 201 to make contact with the first side 51 (radially outwardly) of the dust shield 50 . A contact seal is formed between the two surfaces, which enhances the sealing effect, and the surface roughness of the first side 51 facing the first main sealing lip 201 is very small, so that the friction force and friction torque between the two will not be large. , so that the wear of the first main sealing lip 201 can be reduced. At the same time, the third side 50 of the dustproof member 50 is in contact with the wedge-shaped contact portion of the second main sealing lip 202 . A contact seal is formed between the three sides 53 (the radially outer surfaces thereof). Thereby, the dustproof member 50 , the first main sealing lip 201 , the second main sealing lip 202 , and the skeleton 10 (the skeleton radial portion 103 ) and/or the sealing part 20 located at the first main sealing lip 201 and the second main sealing lip 202 The portion between the sealing lips 202 defines a sealing cavity G around it. Similarly, the surface roughness of the third side 53 facing the second main sealing lip 202 is very small, so that the friction force and friction torque between the two are not very large, so that the wear of the second main sealing lip 202 can be reduced . According to the present invention, the second main sealing lip 202 can achieve the sealing effect of the traditional sealing assembly, and isolate the medium such as lubricating oil. Even if a small amount of lubricating oil breaks through the sealing of the second main sealing lip 202, the first main sealing The lip 201 further seals, and the lubricating oil reaching the second main sealing lip 202 can serve to lubricate it. Through the multiple sealing structure of the present invention, the overall sealing effect of the sealing assembly is significantly enhanced compared with the traditional sealing assembly.

(Second Embodiment)

As shown in FIG. 3 , the basic structure of the seal assembly according to the present embodiment is the same as that of the seal assembly according to the first embodiment, and their differences include the configuration of the second main sealing lip 202 .

In the seal assembly according to the present embodiment, as shown in the cross-sectional view of FIG. 3 , the second main sealing lip 202 extends in an arcuate shape toward the radially inner side and simultaneously toward the axially inner side in the configuration of an arc-shaped thin plate, wherein the second main sealing lip 202 The thickness of the sealing lip 204 in the radial direction R is smaller than the thickness of the first main sealing lip 201 in the radial direction R, and the second main sealing lip 202 is in contact with the third side 53 of the dustproof member 50 with an arc portion having a certain length, thereby forming a seal.

Since the second main sealing lip 202 has the configuration of an arc-shaped thin plate, the amount of interference between the second main sealing lip 202 and the third side 53 may be greater than the amount of interference between the wedge-shaped contact portion and the third side 53 in the first embodiment, so it may not be the second The main sealing lip 202 is provided with a spring. Therefore, although the amount of interference between the second main sealing lip 202 and the third side 53 is relatively large, the contact pressure between the second main sealing lip 202 and the third side 53 can still be reasonably controlled, so that large wear is not easily generated.

It can be understood that the amount of interference between the second main sealing lip 202 and the third side 53 mentioned here may refer to the natural state of the part of the second main sealing lip 202 that is in contact with the third side 53 from the unassembled state. The maximum deformation/displacement in the radial direction R of the assembled state.

Preferably, the axial section of the second main sealing lip 202 as a whole has an arcuate profile that protrudes radially inward. Compared with the wedge-shaped contact portion of the second main sealing lip 202 in the first embodiment, this slender and arc-shaped configuration has the characteristics of being easily deformed, even if no external force is applied to it by a spring or the like, it can be realized, for example, Greater interference with mating components, resulting in greater contact force, resulting in better sealing.

Although the specific technical solutions of the present invention are described in detail in the above specific embodiment, it should be noted that:

(1) Although the configuration in which the second main sealing lip 202 has an arc-shaped thin plate is described in the above-mentioned specific embodiment, the present invention is not limited thereto, and the first main sealing lip 201 may also have a configuration of an arc-shaped thin plate.

(2) The thickness and material of the dustproof member 50 can be selected according to the requirements of interference fit.

(3) The second main sealing lip 202 may be made of the same or different material as the first main sealing lip 201 , including but not limited to fluororubber (FKM), acrylate rubber (ACM), and the like.

Claims (10)

1. A seal assembly for sealing between a first and a second relatively rotatable member, the seal assembly being generally annular and comprising a skeleton (10) for fixed mounting to the second member and a seal portion (20), the seal portion (20) comprising a first primary seal lip (201) extending from a radially inner end of the skeleton (10) towards an axially inner side and towards a radially inner side,

the seal assembly further comprises:

a second primary seal lip (202) disposed radially spaced from the first primary seal lip (201); and

a dust guard (50), the dust guard (50) including a first side (51) extending generally along an axial direction (A) of the seal assembly, a second side (52), and a third side (53) extending generally along the axial direction (A), the second side (52) connecting the first side (51) and the third side (53), the first side (51) for fixedly mounting the dust guard (50) to the first member, the first primary seal lip (201) configured to form a contact seal with the first member or the first side (51), the second primary seal lip (202) configured to form a contact seal with the third side (53) such that the dust guard (50), the first primary seal lip (201), the second primary seal lip (202), and a portion of the skeleton and/or the seal between the first primary seal lip (201) and the second primary seal lip (202) define a seal around the dust guard (50), the first primary seal lip (201), the second primary seal lip (202), and a portion of the skeleton and/or the seal portion between the first primary seal lip (201) and the second primary seal lip (202) And a cavity (G) is sealed.

2. The seal assembly of claim 1, wherein the second primary seal lip (202) has a similar configuration and dimensions as the first primary seal lip (201).

3. A seal assembly according to claim 2, characterized in that a first spring (31) is arranged radially outside the first primary seal lip (201), which first spring (31) exerts a spring force on the first primary seal lip (201) directed radially inwards,

the second main seal lip (202) extends from an axial inner side surface of a frame radial portion (103) of the frame (10) toward a radial inner side and also toward the axial inner side, wherein a second spring (32) is provided radially outside the second main seal lip (202), and the second spring (32) exerts a spring force toward the radial inner side on the second main seal lip (202).

4. The seal assembly of claim 1, wherein the second primary seal lip (202) has an arcuate web configuration and extends arcuately toward a radially inner side and simultaneously toward an axially inner side.

5. The seal assembly according to claim 4, characterized in that the thickness of the second primary seal lip (202) in the radial direction (R) of the seal assembly is smaller than the thickness of the first primary seal lip (201) in the radial direction (R).

6. The seal assembly of claim 4, wherein a radially outer side of the second primary seal lip (202) is free of a spring exerting a spring force thereon.

7. The seal assembly of claim 5, wherein the second primary seal lip (202) contacts the third side (53) in an arcuate portion having a length.

8. The seal assembly of claim 7, characterized in that the axial cross section of the second primary seal lip (202) has overall an arcuate profile that is convex towards the radially inner side.

9. The seal assembly according to any one of claims 1 to 8, characterized in that the second primary sealing lip (202) is arranged in a radially intermediate position of the skeleton (10).

10. The seal assembly according to any one of claims 1 to 8, characterized in that the first main sealing lip (201) is in contact with the first edge (501) and the second main sealing lip (202) is in contact with a radially outer side of the third edge (503).

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