Sealing device

Abstract

The invention provides a sealing device which comprises an elastic sealing body, a first sealing lip is formed on one radial side of the elastic sealing body, and the first sealing lip is provided with a lip end and used for elastically abutting against a first component capable of rotating relative to the sealing device. A first oil storage structure is formed on the side face, facing the air side, of the lip end of the first sealing lip and comprises a plurality of fin-shaped protruding edges parallel to the axial direction and distributed in the circumferential direction and a return structure continuously extending in the circumferential direction. By means of the sealing device, the improved lubricating condition, the good sealing effect and the longer service life can be achieved.

Description

Technical Field

[0001] The present disclosure relates to a sealing device for establishing a dynamic seal between two components capable of relative rotation. The sealing device is particularly suitable for application scenarios in which two rotation directions are frequently switched. Background Art

[0002] In the prior art, it is known to seal between two parts, such as a rotating shaft and a housing, or between the inner ring and the outer ring of a bearing. Such a sealing device is generally annular and is usually made of a soft, elastic material. A sealing lip is usually formed on one side of the sealing device. During use, the sealing lip elastically rests on the rotating part, forming a suitable radial contact pressure on the narrow contact sliding surface, thereby forming a seal between the air side and the oil side - preventing the lubricating oil from leaking to the outside, while preventing the outside gas or liquid from penetrating into the machine equipment from the seal.

[0003] However, when the rotating part rotates relative to the sealing device, the pumping effect will cause the air side to flow toward the oil side, which will cause the sealing lip to lack lubrication of the lubricating oil on the air side. Especially when the rotating shaft runs at high speed, the sealing lip on the air side may even be in a state of dry friction, which will seriously affect the service life and sealing effect of the sealing device.

[0004] Although in some applications, such as when the rotating shaft rotates in a fixed direction relative to the sealing device for a long time, an oil film may form on the contact surface to provide lubrication. However, in some specific application scenarios, such as the gear shifting system of a transmission, it is difficult to form an oil film because the rotating shaft rotates in two directions relative to the seal and frequently starts suddenly and rotates to high speed and then stops suddenly. As a result, friction cannot be avoided, resulting in a low service life of the sealing device and poor sealing effect. Summary of the invention

[0005] In order to overcome the above defects and shortcomings, the present disclosure provides a sealing device which can provide improved lubrication conditions, good sealing effect and longer service life.

[0006] The present disclosure provides a sealing device, comprising: an elastic sealing body, which is formed with a first sealing lip on one radial side, the first sealing lip having a lip end portion for elastically abutting against a first component that can rotate relative to the sealing device, and is characterized in that the lip end portion of the first sealing lip is formed with a first oil storage structure on the side facing the air side, the first oil storage structure comprising: a plurality of fin-shaped ridges parallel to the axial direction and distributed in the circumferential direction, and a return structure extending continuously in the circumferential direction.

[0007] By means of the oil storage space formed on the air side of the sealing lip by the oil storage structure, a certain amount of lubricating oil can be kept on the air side in static state. In dynamic state, the stored lubricating oil can be pumped back into the cavity with the help of the enhanced pumping action generated by the fin-shaped ridges. As a result, an oil film can always be maintained near the contact surface. The oil film plays a lubricating role, thereby improving the lubrication conditions and thus increasing the service life of the sealing device. In addition, the enhanced pumping action also provides a good sealing effect, that is, it effectively prevents the lubricating oil from leaking from the oil side to the air side. In addition, arranging multiple fin-shaped ridges in a direction substantially parallel to the axial direction can ensure that the same sealing effect can be achieved when the rotating part rotates in either of the two rotation directions. Therefore, it is particularly suitable for application scenarios with frequent switching between the two rotation directions, such as the shifting system of a transmission.

[0008] According to an embodiment of the present disclosure, a plurality of fin-shaped ridges are arranged in parallel and at equal distances from each other.

[0009] According to an embodiment of the present disclosure, the fin-shaped rib is configured such that, in response to the first member rotating relative to the sealing device, the fin-shaped rib can undergo elastic bending deformation.

[0010] The curved fin-shaped ridges form a blade structure similar to an impeller, whereby, under the guidance of the curved fin-shaped ridges, the lubricating oil around the fin-shaped ridges is pushed away from the fin-shaped ridges by the centrifugal force (or thrust), thereby further enhancing the pumping effect. In addition, the fin-shaped ridges can be bent (or flipped) in different directions according to the direction of rotation, thereby ensuring that the same enhanced pumping effect can be achieved in any direction of rotation.

[0011] According to an embodiment of the present disclosure, the fin-shaped ridge has a gradually narrowing cross section from the air side to the oil side in the axial direction, or in other words, has a gradually widening cross section from the oil side to the air side. According to an embodiment of the present disclosure, at least a portion of the top of the fin-shaped ridge is axially aligned with the first member.

[0012] This fin-shaped ridge with a gradual cross section (or a gradual height) can achieve a better fit with the first member. In addition, compared with the conventional ridge with a constant cross section over the entire length, the fin-shaped ridge with a gradual height in the present disclosure can simultaneously take into account both an efficient pumping effect and a good sealing effect. In addition, even if wear occurs at the sliding contact surface over time, this fin-shaped ridge with a gradual cross section will not start to decrease in the axial contact length too early, so a satisfactory pumping effect can still be obtained.

[0013] According to an embodiment of the present disclosure, the fin-shaped ridge has a gradually decreasing size from its root to its top. According to an embodiment of the present disclosure, the fin-shaped ridge has a triangular cross-section. According to a preferred embodiment of the present disclosure, the ratio of the height of the triangle to the bottom width is greater than or equal to 2.

[0014] By designing the fin ribs into a relatively flat "sheet-like" shape the flexure of the fin ribs will be facilitated, thereby enhancing the pumping effect.

[0015] According to an embodiment of the present disclosure, the elastic sealing body is further formed with a second sealing lip on the same radial side as the first sealing lip, the lip end of the second sealing lip elastically rests against the first component, and a second oil storage structure is formed on the side of the lip end of the second sealing lip facing the oil side, and the second oil storage structure is structurally identical to the first oil storage structure.

[0016] According to an embodiment of the present disclosure, the sealing device further includes: a skeleton, which is covered by the elastic sealing body and is used to provide internal support or reinforcement for the sealing device. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Further details, features and advantages of the present disclosure are disclosed in the following description of exemplary embodiments in conjunction with the accompanying drawings, in which:

[0018] Figure 1 is a partial side cross-sectional view of a sealing device according to an embodiment of the present disclosure;

[0019] Figure 2 A partial view of an oil storage structure of a sealing device according to an embodiment of the present disclosure;

[0020] Figure 3 A view showing a static state of a plurality of fin-shaped ridges according to an embodiment of the present disclosure;

[0021] Figure 4 To show Figure 3 A magnified view of the static morphology of one of the fin-shaped ridges;

[0022] Figure 5 A view showing a dynamic state of a plurality of fin-shaped ridges according to an embodiment of the present disclosure;

[0023] Figure 6 To show Figure 5 A magnified view of the dynamic morphology of one of the fin-shaped ridges;

[0024] Figure 7 FIG. 4 is a view showing a cross section of a fin-shaped rib according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0025] The exemplary embodiments of the present invention will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be implemented in various forms, and should not be understood as the embodiments of the present application being limited to the embodiments set forth herein. On the contrary, providing these exemplary embodiments can make the embodiments of the present application more comprehensive and complete, and more convenient for fully conveying the inventive concept to those skilled in the art. The same reference numerals in the figures represent the same or similar elements, components or parts, and thus their repeated description will be omitted.

[0026] It should be understood that the direction or position terms mentioned in the present invention, such as "left", "right", "lower left", "lower right", "top", "bottom", "inside", "outside", etc., are only used to illustrate and understand the present invention, and are not used to limit the present invention.

[0027] In addition, the embodiments described in the specific embodiment mode are only part of the embodiments of the present invention, rather than all the embodiments. Under the premise of conforming to the technical concept of the embodiments of the present disclosure, the features, structures, characteristics or other details described in a specific embodiment do not exclude that they can be combined in one or more other embodiments in a suitable manner.

[0028] In addition, in the following text, the terms "axial", "radial" and "circumferential" are all defined based on the rotation axis (or center axis) of the rotating component, where "axial" is a direction parallel to or coinciding with the center axis of the rotating component, "radial" is a direction perpendicular to the center axis, and "circumferential" is a direction surrounding the center axis.

[0029] Figure 1 A sealing device 100 according to an embodiment of the present disclosure is shown, which is disposed between a first component 200 and a second component 300 along a radial direction R. The sealing device 100 is fixed to the second component 300 , and the first component 200 is rotatable relative to the sealing device 100 .

[0030] exist Figure 1 In the illustrated embodiment, the first component 200 is a rotating shaft, and the corresponding second component 300 is a housing. It should be understood that in other embodiments, the first component 200 may be an inner ring of a bearing, and the corresponding second component 300 may be an outer ring of a bearing.

[0031] like Figure 1 As shown, the sealing device 100 isolates the air side A on the left from the oil side O on the right, thereby preventing the lubricating oil from leaking from the oil side O to the air side A to the outside, and preventing the gas and liquid on the air side A from penetrating into the oil side O from the seal.

[0032] like Figure 1As shown, the sealing device 100 includes an elastic sealing body 1, which can be made of rubber, for example. The radial outer side of the elastic sealing body 1 is fixed to the housing 300. The elastic sealing body 1 is formed with a first sealing lip 11 extending obliquely to the right and downward on the radial inner side, and the first sealing lip 11 has a lip end 12 for elastically abutting against a rotating shaft 200 that can rotate relative to the sealing device 100. In this way, an appropriate radial pressure is formed at a generally narrow annular sliding contact surface (e.g., sliding contact zone), thereby establishing a seal between the air side A and the oil side O.

[0033] Optional or additional, such as Figure 1 As shown, the sealing device 100 may further include a skeleton 2, which is covered by the elastic sealing body 1, and is used to provide internal support or reinforcement for the sealing device 100.

[0034] It should be pointed out that although Figure 1 In the illustrated embodiment, the first sealing lip 11 is arranged radially inward, but it should be understood that, depending on the relative position of the first component and the second component, the first sealing lip may also be directed radially outward. In the context of the disclosed embodiment, "radially inward" is the direction toward the rotation axis, and "radially outward" is the direction away from the rotation axis.

[0035] Continue to refer Figure 1 The lip end portion 12 is formed with a first oil storage structure 13 along the circumferential direction C on a side surface 121 facing the air side (ie, similar to a truncated cone surface). Figure 2 FIG. 1 shows a partial enlarged view of the first oil storage structure 13. Figure 2 As shown, the first oil storage structure 13 includes: a return structure 131 extending continuously along the circumferential direction C and a plurality of fin-shaped ridges 132 distributed along the circumferential direction C and parallel to the axial direction Y.

[0036] exist Figure 1 In the illustrated embodiment, the continuously extending return structure 131 is a continuous annular return line in the circumferential direction C, and the plurality of fin-shaped ridges 132 are arranged to be equidistant and parallel to each other, that is, evenly spaced in the circumferential direction C. When in use, the return structure 131 elastically abuts against the surface of the first member 200 in the circumferential direction C with appropriate pressure, thereby forming an annular sealed oil storage space on the air side A, and the return structure 131 can prevent the lubricating oil from further leaking to the air side A.

[0037] By means of the first oil storage structure 13, a certain amount of lubricating oil can be maintained on the air side A (the left side of the sealing lip) of the first sealing lip in static state. During rotation, the contained lubricating oil can be pumped back into the cavity by means of the enhanced pumping action provided by the fin-shaped ridge 132. In this way, an oil film is always maintained at the contact surface between the sealing lip 11 and the rotating shaft 200. The oil film provides improved lubrication conditions, thereby reducing friction when the sealing device 100 rotates relative to the first component 200. In addition, the enhanced pumping action also improves the sealing performance of the sealing device 100, because leakage from the lubricating oil O side can be reliably prevented.

[0038] In addition, it would be advantageous to set the plurality of fin-shaped ridges 132 to be parallel to the axial direction Y. This is because, at this time, no matter which direction the rotating shaft 200 rotates relative to the sealing device 100 in the two rotation directions, the same good sealing effect can be achieved, and therefore it is particularly suitable for application scenarios where the first component 200 frequently switches between the two rotation directions relative to the sealing device 100, for example, in the shifting system of a transmission. In contrast, in the prior art, a plurality of ridges are usually set to be tilted at a certain angle relative to the axial direction Y, and this tilted orientation may only be able to obtain a good sealing effect in a specific rotation direction. In other words, if the rotating shaft rotates in the direction opposite to the above-mentioned specific rotation direction, leakage may occur.

[0039] Furthermore, in some embodiments, the fin-shaped ridge 132 may also be configured to undergo elastic bending deformation (or flipping / tilting) in response to the rotation of the first component 200 relative to the sealing device 100 .

[0040] Figure 3 and Figure 4 The static state of the fin-shaped rib 132 according to one example of the present disclosure is shown. Figure 5 and Figure 6 The fin-shaped ridges 132 are shown in a dynamic state.

[0041] Specifically, since the fin-shaped ridges 132 are made of a flexible material (eg, rubber), the following characteristics can be achieved by appropriately designing the shape of the fin-shaped ridges 132:

[0042] When the sealing device 100 is in a static state relative to the first member 200, the fin-shaped ridges 132 maintain a straight shape by virtue of their own material strength and shape. When the sealing device 100 rotates relative to the first member 200 in the direction indicated by the arrow 51, the multiple fin-shaped ridges 132 thereon will be elastically bent (or flipped) in the direction indicated by the arrow 61 under the action of the friction force on the surface of the first member 200, forming a blade structure similar to an impeller. In this way, under the guidance of the curved fin-shaped ridges 132, the lubricating oil around the fin-shaped ridges 132 will be pushed away from the fin-shaped ridges 132 under the action of the centrifugal force (or thrust). Compared with the straight fin-shaped ridges 132, the curved fin-shaped ridges 132 further enhance the pumping effect, so the lubricating oil on the air side will be more efficiently pumped back to the lubricating oil side O, thereby further improving the lubrication effect and the sealing effect. When the rotation stops, the fin-shaped ridges 132 will return to their original straight state.

[0043] Furthermore, depending on the different rotation directions, the fin-shaped ridges 132 can be freely bent (or flipped) toward a corresponding one of the two directions, in this way, an enhanced pumping effect can be flexibly achieved in both rotation directions.

[0044] In some embodiments, the fin-shaped ridge 132 has a gradually decreasing cross-section from the air side A to the oil side O along the axial direction Y. In other words, the fin-shaped ridge 132 has a gradually increasing cross-section from the oil side O to the air side A along the axial direction Y. Figure 4 In the specific example shown, although the size of the cross section of the fin-shaped ridge changes gradually along the axial direction Y, the shape of the cross section at any position along the axial direction Y is ensured to remain “similar”.

[0045] In some embodiments, at least a portion of the top of the fin-shaped ridge 132 is in contact with the surface of the first component 200 in the axial direction Y.

[0046] For example, the top of the fin-shaped ridge 132 may only be in contact with the surface of the first member 200 at a portion close to the sliding contact surface, and not in contact with the first member at the remaining portion away from the sliding contact surface. In this case, the annular oil storage space on the air side A is fluidically connected as a whole.

[0047] For another example, the top of the fin-shaped ridge 132 may also be in contact with the surface of the first member 200 over the entire top length in the axial direction Y. In this case, the annular oil storage space on the air side A is divided into a plurality of subspaces 133 by a plurality of fin-shaped ridges 132, and each subspace 133 is surrounded by two adjacent fin-shaped ridges 132 and the return structure 131 (see Figure 2 ).

[0048] The cross section (or height) of the fin-shaped ridge 132 is designed to gradually increase from the oil side O to the air side A, so that the fin-shaped ridge 132 can better fit the surface of the rotating shaft 200 in the axial direction Y.

[0049] Compared with the conventional fin-shaped ridges having a constant cross section over the entire length, the fin-shaped ridges 132 with a gradually changing height have the following beneficial effects:

[0050] First, both efficient pumping effect and good sealing effect can be taken into account at the same time. Specifically, if the entire height of the ridge is designed to be too low, the pumping effect may be reduced. This is because, in general, the higher the ridge height, the stronger the pumping effect. On the contrary, if the entire height of the ridge is designed to be too high, the sealing effect at the sliding contact surface between the end of the sealing lip and the rotating shaft may be damaged. This is because an excessively high ridge height may cause the radial pressure between the lip end of the sealing lip and the shaft surface to weaken.

[0051] In addition, as time goes by, the contact surface may be worn due to long-term use. However, even if wear occurs, the fin-shaped ridge with a gradual cross-section can still achieve a satisfactory pumping effect. Specifically, since the height of the fin-shaped ridge 132 gradually increases from the contact surface to the air A side, as the wear progresses, the contact length between the fin-shaped ridge 132 and the rotating shaft 200 in the axial direction will not begin to decrease prematurely, which ensures that a higher pumping effect can be obtained both during initial installation and after long-term use.

[0052] In some embodiments, the fin-shaped ridge 132 has a gradually decreasing size from its root to its top. Figure 7 As shown, the fin-shaped ridge 132 may have a triangular cross-section. In some examples, the ratio of the height H to the bottom width W of the triangle is configured to be greater than or equal to 2 (i.e., H / W ≥ 2). Designing the fin-shaped ridge 132 to be a relatively flat sheet shape will facilitate the bending of the fin-shaped ridge 132, thereby enhancing the pumping effect.

[0053] Return to reference Figure 1 In some embodiments, optionally or additionally, the elastic sealing body 100 is on the same radial side of the first sealing lip 11 ( Figure 1 A second sealing lip 14 may also be formed on the radially inner side (in the example of the embodiment) to prevent the intrusion of dust from the air side A. The second sealing lip 14 extends obliquely to the lower left, and a lip end 15 of the second sealing lip elastically abuts against the first component 200. A second oil storage structure (not shown) is formed on one side 152 of the lip end 15 of the second sealing lip 14 toward the oil side O, and the second oil storage structure is structurally identical to the first oil storage structure.

[0054] Reference numerals list

[0055] 1 Elastic sealing body

[0056] 11First sealing lip

[0057] 12 Lip end of the first sealing lip

[0058] 121 Side facing the air side

[0059] 13The first oil storage structure

[0060] 131 Return structure

[0061] 132 fin-shaped ridges

[0062] 133 Subspace

[0063] 14 Second sealing lip

[0064] 15 Lip end of the second sealing lip

[0065] 152 Side facing the oil side

[0066] 2 Skeleton

[0067] 100 Sealing Device

[0068] 200 First Component

[0069] 300 Second Component

[0070] AAir side

[0071] O Oil side

[0072] R Radial

[0073] Y axis

[0074] C Circumferential direction

Claims

1. A sealing device (100), comprising: An elastic sealing body (1) is formed with a first sealing lip (11) on one side in a radial direction (R), wherein the first sealing lip (11) has a lip end (12) for elastically abutting against a first member (200) that is rotatable relative to the sealing device, It is characterized in that A first oil storage structure (13) is formed on the side surface (121) of the lip end portion (12) of the first sealing lip (11) facing the air side (A), and the first oil storage structure comprises: a plurality of fin-shaped ridges (132) pointing parallel to the axial direction (Y) and distributed along the circumferential direction (C), and A return structure (131) continuously extends along the circumferential direction (C).

2. The sealing device according to claim 1, wherein The plurality of fin-shaped ridges (132) are arranged in parallel and at equal distances from each other.

3. The sealing device according to claim 1, wherein: The fin-shaped ridge (132) is configured to be able to undergo elastic bending deformation in response to the first member (200) rotating relative to the sealing device (100).

4. The sealing device according to claim 1, wherein: The fin-shaped ridge (132) has a gradually decreasing cross-section from the air side (A) to the oil side (O) along the axial direction (Y).

5. The sealing device according to claim 4, wherein: At least a portion of the top of the fin-shaped ridge (132) is in contact with the first member (200) in the axial direction (Y).

6. The sealing device according to claim 1, wherein: The fin-shaped ridge (132) has a gradually decreasing size from its root to its top.

7. The sealing device according to claim 6, wherein: The fin-shaped ridge (132) has a triangular cross section.

8. The sealing device according to claim 7, wherein: The ratio of the height (H) to the base width (W) of the triangle is greater than or equal to 2.

9. The sealing device according to claim 1, wherein: The elastic sealing body (100) is further formed with a second sealing lip (14) on the same radial side as the first sealing lip (11); a lip end (15) of the second sealing lip (14) elastically abuts against the first component (200); a second oil storage structure is formed on a side (152) of the lip end of the second sealing lip facing the oil side (O); the second oil storage structure is structurally identical to the first oil storage structure.

10. The sealing device according to claim 1, further comprising: The skeleton (2) is covered by the elastic sealing body (1) and is used to provide internal support or reinforcement for the sealing device.

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