CN110005815A - Seals, Shaft Assemblies and Bearings - Google Patents

Abstract

The present invention relates to a sealing device, a shaft assembly and a bearing. A sealing device for sealing between a first member and a second member of a shaft assembly or bearing, the sealing device comprising a skeleton (10) and a sealing portion (20) comprising a transition portion (203) to each other The first main sealing lip (201) and the dustproof lip (202) are connected, the dustproof lip (202) is axially outward from the first main sealing lip (201), and the sealing portion (20) further includes a second main sealing lip (204), the second main sealing lip (204) extends from the dust lip (202) or from the transition portion (203) toward the radially inner side and simultaneously toward the axially inner side and is used to form a contact seal with the first member. The sealing device according to the present invention improves sealing performance and reduces the possibility of leakage without additionally increasing the overall size or space requirements of the sealing device.

Description

Seals, Shaft Assemblies and Bearings

technical field

The present invention relates to the field of sealing, and more particularly to a sealing device for a shaft assembly or bearing, and a shaft assembly and bearing having such a sealing device.

Background technique

For a shaft assembly or bearing, it generally includes a first member (eg, the inner ring of the shaft or bearing in the shaft assembly) and a second member (eg, the housing of the shaft assembly or the outer ring of the bearing) that can rotate relative to each other. ring), however, it may be necessary to seal between these two members during operation, for which a sealing device is provided between the first member and the second member.

In the prior art, the following sealing device is usually used to seal the shaft assembly or the bearing. The sealing device is annular as a whole and as shown in the partial cross-sectional view of FIG.

Specifically, the skeleton 10 is typically made of a hard material such as metal and includes:

an axial portion 101 of the skeleton, which extends substantially along the axial direction A of the sealing device and is intended to be fixed to the housing or the outer ring of the bearing in the shaft assembly, not shown;

The skeleton connecting portion 102, the radially outer end (upper end in FIG. 1) of which is connected to the axial outer end (the left end in FIG. 1) of the skeleton axial portion 101, is connected from the skeleton axial portion The axially outer end of 101 extends toward the radially inner side while extending toward the axially outer side, and the radially inner end (lower end in FIG. 1 ) of the skeleton connecting portion 102 is connected to the radially outer side of the skeleton radial portion 103 described below. terminal connection; and

The skeleton radial portion 103 extends from the radially inner end of the skeleton connecting portion 102 toward the radially inner side along the radial direction R of the sealing device.

Further, the sealing portion 20 is attached to the skeleton 10 , mainly to the skeleton connecting portion 102 and the skeleton radial portion 103 . The seal 20 comprises a main sealing lip 211 extending from the radially inner end of the skeleton radial portion 103 to, for example, the inner ring of a shaft or bearing in a shaft assembly not shown, by means of a spring located radially outside of the main sealing lip 211 The spring 30 is in contact with the shaft or the inner ring of the bearing, and the spring 30 always exerts a spring force toward the radially inward direction of the main seal lip 211 . In this way, the main sealing lip 211 achieves a contact seal with the inner ring of the shaft or bearing.

In addition, the sealing portion 20 also includes a dust lip 202 extending from the radially inner end of the skeleton radial portion 103 towards the inner ring of the shaft or bearing, the dust lip 202 being located axially outward of the main sealing lip 211 and passing through the transition portion 203 is connected to the main sealing lip 211, wherein there is a slight gap between the radially inner end of the dust lip 202 and the inner ring of the shaft or bearing. In this way, the dust lip 202 achieves a non-contact seal with the inner ring of the shaft or bearing.

The sealing device having the above structure is mainly used in industrial and automotive systems. For sealed systems, leakage and wear are of particular concern. In most cases of seal failure, leakage or leakage due to severe wear is the primary cause of failure.

SUMMARY OF THE INVENTION

The present invention is made based on the above-mentioned deficiencies of the prior art. The purpose of the present invention is to provide a sealing device that can improve the sealing performance and reduce the possibility of leakage without additionally increasing the overall size or space requirements of the sealing device. Another object of the present invention is to provide a shaft assembly and a bearing including the sealing device.

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 device for sealing between a first member and a second member of a shaft assembly or bearing, the first member being rotatable relative to the second member, and the sealing device is in the form of a ring as a whole shape and includes a skeleton and a sealing portion, wherein the sealing portion includes a first main sealing lip and a dust lip connected to each other by a transition portion, the first main sealing lip extending from the skeleton toward the axial inner side while facing The dust lip extends radially inward and is used to form a contact seal with the first member, the dust lip extends toward the radial inner side while extending from the frame toward the axial outer side, wherein the dust lip is larger than the first member. The main sealing lip is axially outward, and is characterized in that:

The sealing portion further comprises a second main sealing lip extending from the dust lip or from the transition portion towards the radially inward and simultaneously towards the axially inward and for forming with the first member Contact seal.

In at least one embodiment, the second main sealing lip extends arcuately from the dust lip or from the transition portion towards the radially inward and at the same time towards the axially inward, the second main sealing lip relative to the The first main sealing lip has an elongated configuration or relative to the dust lip.

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, and the thickness of the second main sealing lip is smaller than the thickness of the dust lip thickness.

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

In at least one embodiment, a plurality of pumping passages recessed toward the radially outer side are provided on the inner peripheral surface of the second main sealing lip.

In at least one embodiment, the inner peripheral surface of the second main sealing lip has a plurality of ridges.

In at least one embodiment, the protruding strip is inclined with respect to the circumferential direction, so that a thread structure is formed on the inner circumferential surface of the second main sealing lip as a whole.

In at least one embodiment, an annular space is formed between the inner peripheral surface of the first main sealing lip and the outer peripheral surface of the second main sealing lip, and lubricant is stored in the annular space.

The present invention also provides a shaft assembly comprising a shaft, a housing, and a sealing device according to the present invention mounted between the shaft and the housing.

The present invention also provides a bearing comprising an inner ring, an outer ring, and a sealing device according to the present invention mounted between the inner ring and the outer ring.

By providing a second main sealing lip that forms a contact seal with the first member (eg, the inner ring of the shaft or bearing), it is possible to achieve this without affecting the first main sealing lip and without additionally increasing the overall size or space requirements of the sealing arrangement Improve sealing performance and reduce the possibility of leakage.

Description of drawings

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

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

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

4 is a schematic partial cross-sectional view of a sealing device according to a third 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 201 First main sealing lip 202 Dust lip 203 Transition part 204 Second main sealing lip 205 Pumping channel 206 Raised strip 211 Main sealing lip 30 Spring A Axial R Radial C Circumferential G Contact S Annular 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 sealing device of the present invention is annular. Unless otherwise specified, "axial", "radial" and "circumferential" described in the following detailed description refer to the axial, radial and circumferential directions of the sealing device, respectively. In addition, in the following specific embodiments, the axially outer side (environment side) is the left side in each drawing, and the axially inner side (sealed side/lubricant side/oil side) is the right 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.

A number of exemplary embodiments according to the present invention will be described below.

(first embodiment)

In this embodiment, as shown in FIG. 2 , the sealing device includes a skeleton 10 and a sealing portion 20 , preferably a spring 30 , wherein the sealing portion 20 is attached to the skeleton 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 the present embodiment is the same as that of the skeleton 10 of the prior art sealing device 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, a frame connecting portion 102 extending from an axially outer end of the frame axial portion 101 , and a radial direction from the frame connecting portion 102 . The inner end extends along the radial direction R toward the radially inner radial portion 103 of the skeleton.

The structure of the sealing portion 20 in the present embodiment is the same as that of the sealing portion 20 of the prior art sealing device shown in FIG. 1 . As shown in FIG. 2 , in the present embodiment, the sealing portion 20 is mainly attached to the skeleton connecting portion 102 and the skeleton radial portion 103 . The seal portion 20 includes a first main seal lip 201 extending from the skeleton 10 toward the axial inner side while extending toward the radial inner side for contacting with the inner ring of the shaft or bearing in the shaft assembly, and a first main sealing lip 201 extending from the skeleton 10 toward the axial outer side. At the same time, the dust lip 202 extends radially inward. The first main sealing lip 201 can abut against the inner ring of the shaft or bearing from the radially outer side of the inner ring of the shaft or bearing in the shaft assembly through the spring 30, and the spring 30 always exerts a force on the first main sealing lip 201 toward the radially inner side. the spring force. The dust lip 202 is located axially outward of the first main sealing lip 201 and is connected to the first main sealing lip 201 via a transition portion 203 .

However, in the present embodiment, the sealing portion 20 additionally has the second main sealing lip 204 in addition to the first main sealing lip 201 , and the second main sealing lip 204 is arced from the dust lip 202 toward the radially inner side. And at the same time extend towards the axial inner side. Alternatively, although not shown, the second main sealing lip 204 may also extend from the transition portion 203 in an arcuate manner towards the radially inner side and at the same time towards the axially inner side. As shown in the cross-sectional view of FIG. 2 , the second main sealing lip 204 has an elongated configuration relative to the first main sealing lip 201 , that is, the thickness of the second main sealing lip 204 in the radial direction R is much smaller than that of the first main sealing lip The thickness of the lip 201 in the radial direction R, and the length of the second main sealing lip 204 in the axial direction A is much greater than its own thickness in the radial direction R. Preferably, the second primary sealing lip 204 also has an elongated configuration relative to the dust lip 202, ie, the thickness of the second primary sealing lip 204 is less than the thickness of the dust lip 202, and the thickness of the second primary sealing lip 204 is smaller than that of the dust lip 202. The length is greater than the length of the dust lip 202 . It should be understood that the elongated configuration of the second primary sealing lip 204 in the present application refers to an elongated configuration in its axial cross section. The thickness and length of the second main sealing lip 204, the first main sealing lip 201 and the dust lip 202 are also the thicknesses and lengths measured in the axial section of the sealing device.

Since the second main seal lip 204 has an elongated configuration, the amount of interference with the inner race of the shaft or bearing is preferably greater than the amount of interference of the first main seal lip 201 with the inner race of the shaft or bearing. Since the second main sealing lip 204 is not provided with a spring, although the amount of interference between the second main sealing lip 204 and the inner ring of the shaft or bearing is relatively large, the contact pressure between the second main sealing lip 204 and the inner ring of the shaft or bearing can still be reasonable control, so that it is not easy to produce large wear.

It can be understood that the amount of interference between the second main sealing lip 204 and the inner ring of the shaft or bearing mentioned here may refer to the part of the second main sealing lip 204 that is in contact with the inner ring of the shaft or the bearing and is never installed on the shaft The maximum deformation/displacement in the radial direction R from the natural state of the assembly or bearing to the installed state of the shaft assembly or bearing. The amount of interference of the first main sealing lip 201 with the inner ring of the shaft or bearing mentioned here may mean that the part of the first main sealing lip 204 that is in contact with the inner ring of the shaft or bearing is never mounted to the shaft assembly or bearing And the maximum deformation/displacement amount in the radial direction R from the natural state without the spring force of the spring 30 to the installed state of the shaft assembly or the bearing.

Preferably, the axial section of the second main sealing lip 204 as a whole has an arc-shaped profile that protrudes radially inward. The second main sealing lip 204 is based on this elongated and arcuate configuration with respect to the angular contact point G where the radially inner side of the first main sealing lip 201 comes into contact with, for example, the inner ring of a shaft or a bearing. It has the characteristics of easy deformation, even if there is no external force applied to it by a spring, for example, it can achieve greater interference with the inner ring of the shaft or the bearing, thereby generating a greater contact force, so as to achieve a better sealing effect. By additionally providing the second main sealing lip 204 on the dust lip 202 or the transition portion 203, the sealing performance can be improved without affecting the first main sealing lip 201 and without additionally increasing the overall size or space requirements of the sealing device , greatly reduce the possibility of leakage.

(Second Embodiment)

As shown in FIG. 3 , the basic structure of the sealing device according to this embodiment is the same as that of the sealing device according to the first embodiment, and their differences include: in the sealing device according to the The two main sealing lips 204 are provided with a plurality of pumping channels 205, and the pumping channels 205 can be configured as elongated, triangular, rectangular or trapezoidal concave portions. In particular, the pumping channel 205 is provided on the inner peripheral surface of the second main sealing lip 204 .

By providing the pumping channel 205, a pumping effect can be generated for fluids such as grease and air, so that the second main sealing lip 204 is rapidly dissipated by these fluids. In this way, the sealing device of the present invention improves the heat dissipation efficiency of the second main sealing lip 204, reduces the temperature of the second main sealing lip 204, improves the lubrication state of the contact part of the second main sealing lip 204, and further improves the overall sealing the life of the device.

In an alternative embodiment, the pumping channel 205 is capable of pumping lubricant leaking or about to leak from the first main seal lip 201 and the second main seal lip 204 back to the axial inner side of the seal (lubricant side/ oil side), which can improve the effect of preventing lubricant leakage.

As shown in FIG. 3 , between the first main sealing lip 201 and the second main sealing lip 204 , more specifically, between the inner peripheral surface of the first main sealing lip 201 and the outer peripheral surface of the second main sealing lip 204 An annular space S is formed. In the case where the sealing device is mounted on the shaft assembly or bearing, the annular space S is closed. A lubricant such as grease can be placed in the annular space S, and the lubricant can especially lubricate the first main sealing lip 201 and the second main sealing lip 204 .

It should be understood that when the sealing device is mounted on the shaft assembly or bearing, although the second main sealing lip 204 is deformed/displaced radially outward, the second main sealing lip 204 will not be in contact with the first main sealing lip 201 contacts, thus, the gap between the distal end of the second main sealing lip 204 and the first main sealing lip 201 allows the lubricant in this annular space S to lubricate the first main sealing lip 201 and the second main sealing lip 204 .

As shown in FIG. 3 , the pumping passage 205 is provided on the inner peripheral surface of the distal end portion of the second main seal lip 204 and may extend obliquely with respect to the axial direction A. As shown in FIG. In particular, the pumping channel 205 extends to the end of the distal end of the second main sealing lip 204, so that it is easier to realize the leakage from the first main sealing lip 201 or the storage in the first main sealing lip 201 and the second main sealing lip The pumping effect of the lubricant within the annular space S between 204 .

It should be understood that in the first embodiment and the third embodiment described later there are also corresponding annular spaces in which lubricants can also be stored.

(third embodiment)

As shown in FIG. 4 , the basic structure of the sealing device according to the present embodiment is the same as that of the sealing devices of the first and second embodiments, and their differences include: in the sealing device according to the present embodiment, the first and second The inner peripheral surfaces of the two main sealing lips 204 have a plurality of protruding strips 206 .

In the present embodiment, as shown in FIG. 4 , the second main sealing lip 204 is configured with a plurality of ridges 206 on its inner peripheral surface, and the ridges 206 are inclined with respect to the circumferential direction C (indicated by dashed lines in FIG. 4 ). , so that a threaded structure is formed on the inner peripheral surface of the second main sealing lip 204 as a whole, and the threaded structure can achieve the same effect as the above-mentioned pumping channel 205, and can achieve a better sealing effect with the inner ring of the shaft or bearing .

In addition, the present invention also provides a shaft assembly or bearing comprising the above-mentioned sealing device. The frame 10 of the sealing device is fixed to the outer ring of the housing or the bearing in the shaft assembly, and the outer ring of the housing or the bearing may not rotate.

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 not explicitly described in the above-mentioned specific embodiments, it should be understood that the sealing device according to the present invention may also include a dust ring, which is used to be fixed on the inner ring of the shaft or the bearing and form a sealed space with the skeleton , thereby making the sealing device according to the present invention a box-type sealing device.

(2) Although the second main seal lip 204 is in contact with, for example, the inner ring of the shaft or the bearing in the above-described specific embodiment, the present invention is not limited to this. The second main sealing lip 204 may also be in contact with the above-mentioned dust ring, for example.

(3) In the above-mentioned specific embodiment, it is described that the shape of the opening of the pumping channel 205 is a shape such as a triangle, a rectangle, or a trapezoid, and the sides of these shapes may not be straight lines.

(4) The second main sealing lip 204 may be made of the same or different material as the first main sealing lip 201 and/or the dust lip 202 . For example, the second primary sealing lip 204 may be made of one or more of rubber, plastic such as PTFE (polytetrafluoroethylene), or other self-lubricating materials.

Claims (10)

1. a kind of sealing device, the sealing being used between shaft assembly or the first component and second component of bearing, described first Component can be rotated relative to the second component, and the sealing device is whole annular in shape and including skeleton (10) and sealing (20), wherein the sealing (20) includes the first primary seal lip (201) being connected to each other by transition part (203) and dust-proof Lip (202), towards radially inner side while first primary seal lip (201) extends from the skeleton (10) towards axially inner side Extend and be used to be formed with the first component and contact sealing, the dustproof lip (202) is outside towards axis from the skeleton (10) Extend while side extends towards radially inner side, wherein the dustproof lip (202) leans on axis than first primary seal lip (201) Outward, which is characterized in that

The sealing (20) further includes the second primary seal lip (204), and second primary seal lip (204) is from the dustproof lip (202) or extend from the transition part (203) towards radially inner side and simultaneously towards axially inner side and be used for and first structure Part forms contact sealing.

2. sealing device according to claim 1, which is characterized in that second primary seal lip (204) is from described dust-proof Lip (202) extends from the transition part (203) towards radially inner side and simultaneously towards axially inner side arc, and described second is main Sealing lip (204) has elongated configuration relative to first primary seal lip (201) or relative to the dustproof lip (202).

3. sealing device according to claim 2, which is characterized in that second primary seal lip (204) is radially (R) Thickness is less than the thickness of first primary seal lip (201) radially (R), and the thickness of second primary seal lip (204) Less than the thickness of the dustproof lip (202).

4. sealing device according to any one of claim 1 to 3, which is characterized in that second primary seal lip (204) Axial cross section integrally have radially inside protrude curved profile.

5. sealing device according to any one of claim 1 to 3, which is characterized in that in second primary seal lip (204) inner peripheral surface is provided with the multiple pumping passages (205) being recessed towards radial outside.

6. sealing device according to any one of claim 1 to 3, which is characterized in that second primary seal lip (204) Inner peripheral surface have multiple raised lines (206).

7. sealing device according to claim 6, which is characterized in that the raised line (206) tilts with respect to the circumferential direction (C), To which the inner peripheral surface in second primary seal lip (204) forms helicitic texture on the whole.

8. sealing device according to any one of claim 1 to 3, which is characterized in that in first primary seal lip (201) it is formed with annular space (S) between the outer peripheral surface of inner peripheral surface and second primary seal lip (204), in annular sky Between be stored with lubricant in (S).

9. a kind of shaft assembly, which is characterized in that the shaft assembly include axis, shell and be mounted on the axis and the shell it Between sealing device according to any one of claim 1 to 8.

10. a kind of bearing, which is characterized in that the bearing includes inner ring, outer ring and is mounted on the inner ring and the outer ring Between sealing device according to any one of claim 1 to 8.