WO2023130419A1

WO2023130419A1 - Seal ring and harmonic reducer

Info

Publication number: WO2023130419A1
Application number: PCT/CN2022/070912
Authority: WO
Inventors: 刘鑫; 吴丽娟; 张建昌; 高翔
Original assignee: 舍弗勒技术股份两合公司; 刘鑫
Priority date: 2022-01-10
Filing date: 2022-01-10
Publication date: 2023-07-13

Abstract

Provided are a seal ring and a harmonic reducer, the seal ring comprising: a seal part (32), the seal part (32) being annular and comprising a first seal lip (33), a second seal lip (34) and a connecting segment (35), the first seal lip (33) being elastically deformable relative to the second seal lip (34) along a radial direction (R) of the seal ring; and an elastic part (31), the elastic part (31) comprising a radial outside portion (311) and a radial inside portion (312), the radial outside portion (311) being connected to the first seal lip (33), and the radial inside portion (312) being connected to the second seal lip (34); when the radial outside portion (311) and the radial inside portion (312) are compressed along the radial direction (R) of the seal ring and are thus close to one another, the elastic part (31) causes the first seal lip (33) and the second seal lip (34) to trend away from one another.

Description

Sealing ring and harmonic reducer

technical field

The invention relates to a sealing ring and a harmonic speed reducer.

Background technique

As shown in FIGS. 1 and 2 , a possible harmonic reducer includes an elastic sleeve 10 , a machine cover 20 and a sealing ring 30 . The machine cover 20 is provided with a cavity 40 for accommodating the PCB (printed circuit board), and the sealing ring 30 is arranged between the elastic sleeve 10 and the machine cover 20. The sealing ring 30 can prevent grease from invading the cavity 40 and damaging the cavity 40 inside the PCB. The sealing ring 30 has two symmetrically arranged sealing angles and two symmetrically arranged sealing feet. The two sealing corners are in interference fit with the elastic sleeve 10 , and the two sealing feet are in interference fit with the machine cover 20 .

When the harmonic reducer is working, the radial dimension of the elastic sleeve 10 changes continuously, and the cross section of the elastic sleeve 10 is a random irregular ellipse at any time. Although the sealing ring 30 is made of rubber and can deform radially, the two sealing angles of the sealing ring 30 still cannot change well with the shape of the elastic sleeve 10, resulting in a gap between the elastic sleeve 10 and the sealing ring 30. There may be gaps between them, which will cause grease to intrude into the cavity 40 and damage the PCB in the cavity 40 .

Contents of the invention

An object of the present invention is to overcome or at least alleviate the shortcomings of the above-mentioned prior art, and to provide a sealing ring with better sealing performance that can be used for, but not limited to, a harmonic reducer.

Another object of the present invention is to provide a harmonic speed reducer including the above sealing ring.

The invention provides a sealing ring, comprising:

A sealing part, the sealing part is annular, the sealing part includes a first sealing lip, a second sealing lip and a connecting section, the first sealing lip is located radially outside the second sealing lip, through the The connecting section connects the first sealing lip and the second sealing lip together, and the first sealing lip is elastically deformable relative to the second sealing lip along the radial direction of the sealing ring; and

an elastic portion comprising a radially outer portion and a radially inner portion, the radially outer portion being connected to the first sealing lip, the radially inner portion being connected to the second sealing lip,

In a state where the radially outer portion and the radially inner portion are compressed in the radial direction of the sealing ring and approach each other, the elastic portion makes the first sealing lip and the second sealing lip have a tend to move away from each other.

In at least one embodiment, a plurality of radially outer portions are provided along a circumferential direction of the sealing ring, and a plurality of radially inner portions are provided along a circumferential direction of the sealing ring.

In at least one embodiment, the elastic part is formed by bending a metal wire, and the elastic part is wrapped inside the sealing part, or the elastic part is arranged on the inner surface of the sealing part.

In at least one embodiment, the elastic portion is stamped from a metal sheet, and the metal sheet has a plurality of slots or holes or openings therein.

In at least one embodiment, the radially outer portions and the radially inner portions are arranged alternately in the circumferential direction of the sealing ring, and there is one radially inner portion between the two radially outer portions, There is one radially outer portion between the two radially inner portions.

In at least one embodiment, the elastic portion is cut along the axial direction of the elastic portion, and viewed along the circumferential direction of the elastic portion, the end of the elastic portion is U-shaped or V-shaped.

In at least one embodiment, the surfaces of the first sealing lip and the second sealing lip are conical surfaces.

In at least one embodiment, the number of the radially outer portion and the radially inner portion is greater than or equal to 40.

The present invention also provides a harmonic reducer, which includes the sealing ring described in any one of the above technical solutions.

In at least one embodiment, the harmonic reducer also includes an elastic sleeve and a cover, and the sealing ring is located between the elastic sleeve and the cover,

The outer peripheral surface of the machine cover is provided with an annular groove for positioning the sealing ring, and the axial length of the contact portion between the first sealing lip and the elastic sleeve is greater than or equal to half of the axial length of the annular groove .

By adopting the above technical solution, the sealing ring of the present invention can better respond to the radial dimension change of the sealing position, and the sealing effect is better, and it can be (but not limited to) suitable for use between the elastic sleeve and the machine cover of the harmonic reducer of the seal.

Description of drawings

Fig. 1 shows a partially cut-away perspective view of a possible harmonic reducer.

Figure 2 shows a partial sectional view of a possible harmonic reducer.

Fig. 3 shows a partial sectional view of a harmonic speed reducer according to an embodiment of the present invention.

Fig. 4 shows a cross-sectional view of a sealing ring of a harmonic reducer according to an embodiment of the present invention.

FIG. 5 shows a partially enlarged view of FIG. 4 .

Fig. 6 shows an enlarged view of a section of a sealing ring of a harmonic speed reducer according to an embodiment of the present invention.

Fig. 7 shows a schematic structural view of the elastic part of the sealing ring of the harmonic reducer according to the embodiment of the present invention.

Fig. 8 shows half of the elastic part of the sealing ring of the harmonic reducer according to the embodiment of the present invention.

Detailed ways

Exemplary embodiments of the present invention are described below with reference to the accompanying drawings.

In the following description, if not stated separately, the axial direction A refers to the axial direction of the sealing ring 3 , the radial direction R refers to the radial direction of the sealing ring, and the circumferential direction C refers to the circumferential direction of the sealing ring. Moreover, the axial direction of the harmonic reducer is consistent with the axial A direction of the sealing ring 3, the radial direction of the harmonic reducer is consistent with the radial R direction of the sealing ring 3, and the circumferential direction of the harmonic reducer is consistent with the radial direction of the sealing ring 3. The circumferential C direction is consistent.

Referring to FIG. 3 to FIG. 8 , the present invention provides a harmonic reducer, which includes an elastic sleeve 1 , a machine cover 2 and a sealing ring 3 .

The elastic sleeve 1 includes an axial part 11 of the elastic sleeve and a radial part 12 of the elastic sleeve. The axial part 11 of the elastic sleeve can extend along the axial direction A and the circumferential direction C of the harmonic reducer. The radial part of the elastic sleeve 12 may extend along the radial direction R and the circumferential direction C of the harmonic reducer.

The cover 2 includes a cover axial part 21 and a cover radial part 22, the cover axial part 21 can extend along the axial direction A and the circumferential direction of the harmonic reducer, and the cover radial part 22 can extend along the harmonic reducer Machine radial R and circumferential extension.

A cavity 4 is formed between the radial portion 12 of the elastic sleeve and the radial portion 22 of the cover, and the cavity 4 can accommodate a PCB (Printed Circuit Board). The sealing ring 3 is arranged between the axial part 11 of the elastic sleeve and the axial part 21 of the machine cover. The sealing ring 3 can prevent the grease on one side of the sealing ring 3 (the left side in FIG. 3 ) from intruding into the cavity 4 and damaging the PCB. (printed circuit board).

The axial part 11 of the elastic sleeve is located on the radially outside of the axial part 21 of the cover. The outer peripheral surface of the axial part 21 of the cover is provided with an annular groove 23. The annular groove 23 is used to accommodate the sealing ring 3 and can limit the sealing ring 3. Move along the axis A, so that the sealing ring 3 can be easily installed in place.

In FIG. 3 , the sealing ring 3 overlaps with the axial part 11 of the elastic sleeve and the axial part 21 of the machine cover. In fact, the sealing ring 3 is installed between the axial part 11 of the elastic sleeve and the axial part 21 of the machine cover. Afterwards, it will be squeezed and deformed to interfere with the axial portion 11 of the elastic sleeve and the axial portion 21 of the machine cover.

As shown in FIGS. 4 to 8 , the sealing ring 3 includes an elastic portion 31 and a sealing portion 32 , the elastic portion 31 can be wrapped inside the sealing portion 32 , or the elastic portion can be disposed on the inner surface of the sealing portion. The cross-section of the sealing ring 3 is U-shaped or V-shaped, and the opening of the U-shaped or V-shaped is facing the axial side of the sealing ring 3 (the side where the grease is located, the left side in FIG. 3 ).

As shown in FIGS. 4 to 6 , the sealing portion 32 includes a first sealing lip 33 , a second sealing lip 34 and a connecting section 35 .

The first sealing lip 33 is located on the radial outer side of the second sealing lip 34 , and the first sealing lip 33 and the second sealing lip 34 are connected together by a connecting section 35 . The first sealing lip 33 is in contact with the elastic sleeve axial portion 11 and has an interference fit. The second sealing lip 34 fits into the ring groove 23 and has an interference fit with the axial portion 21 of the machine cover.

The sealing portion 32 may include rubber, which has certain elasticity, and the first sealing lip 33 can elastically deform relative to the second sealing lip 34 along the radial direction R of the sealing ring. The opening provides a radial space for the first sealing lip 33 and the second sealing lip 34 to approach each other.

In the uncompressed natural state of the sealing ring 3, the surface of the first sealing lip 33 (i.e. the outer peripheral surface of the sealing ring 3) is a conical surface, and the conical surface is directed from the connecting section 35 to the opening of the sealing ring 3. Extending radially inward to radially outward. The surface of the second sealing lip 34 (that is, the inner peripheral surface of the sealing ring 3 ) is a tapered surface, and the tapered surface extends from the radially outer side to the radially inner side in the direction from the connecting section 35 to the opening of the sealing ring 3 . The above-mentioned tapered surface makes the axial side of the first sealing lip 33 and the second sealing lip 34 (the side where the grease is located, the left side in FIG. 3 ) preferentially cooperate with the axial part 11 of the elastic sleeve and the shaft of the machine cover in the interference fit. Contact to the part 21, so as to prevent grease from entering the cavity 4 through the sealing ring 3, and the sealing effect is better.

The axial length of the contact portion of the first sealing lip 33 and the elastic sleeve 1 is preferably greater than or equal to half of the axial length of the ring groove 23 . The axial length of the contact part is longer, which can make the sealing performance better, and the grease is not easy to leak into the cavity 4 .

As shown in Figures 7 and 8, the elastic portion 31 includes a radially outer portion 311, a radially inner portion 312 and a connecting portion 313, the radially outer portion 311 is located on the radially outer side of the radially inner portion 312, and the connecting portion 313 is on the radially outer side of the radially inner portion 312. The radially outer portion 311 and the radially inner portion 312 are connected to the other end sides in the axial direction of the outwardly outer portion 311 and the radially inner portion 312 . The radially outer portion 311 may be located inside the first sealing lip 33 , the radially inner portion 312 may be located inside the second sealing lip 34 , and the connecting portion 313 may be located inside the connecting section 35 . Referring to FIG. 8 , the elastic portion 31 is cut along the axial direction of the elastic portion 31 , and viewed from the circumferential direction of the elastic portion 31 , the end surface of the elastic portion 31 is U-shaped or V-shaped.

The elastic part 31 can provide a radial force that keeps the first sealing lip 33 and the second sealing lip 34 away from each other, so that the first sealing lip 33 is close to the axial part 11 of the elastic sleeve, and the second sealing lip 34 is close to the shaft of the machine cover to section 21. During the continuous random change of the radial size (shape) of the elastic sleeve 1, the elastic part 31 can better keep the first sealing lip 33 close to the elastic by applying elastic force to the first sealing lip 33 and the second sealing lip 34. The axial part of the sleeve 11 and the second sealing lip 34 are in close contact with the axial part 21 of the machine cover, so that the sealing effect of the sealing ring 3 is better.

A plurality of radially outer parts 311 and radially inner parts 312 are evenly arranged in the circumferential direction C, and radially outer parts 311 and radially inner parts 312 are arranged alternately in the circumferential direction C, and between the two radially outer parts 311 There is a radially inner portion 312 between them, and there is a radially outer portion 311 between the two radially inner portions 312 . The radially outer portions 311 and the radially inner portions 312 are densely arranged, the interval between two adjacent radially outer portions 311 is small, and the interval between two adjacent radially inner portions 312 is relatively small. The number of radially outer parts 311 and radially inner parts 312 is preferably greater than or equal to 40. In this embodiment, the number of radially outer parts 311 and radially inner parts 312 is the same, and the number of radially outer parts 311 and radially inner parts 312 is the same. The number of inner parts 312 is greater than 55.

It can be understood that since the cross-section of the elastic sleeve 1 is an irregular ellipse that constantly changes randomly, the radially outer portion 311 and the radially inner portion 312 that are relatively large in number and at relatively small intervals can follow the radial direction of the elastic sleeve 1 . Dimensions change, and are squeezed and deformed, so that the first sealing lip 33 and the second sealing lip 34 can be subjected to the elastic force of the elastic part 31 and have a tendency to move away from each other in the radial direction R, so that the sealing ring 3 is in the elastic sleeve 1 In the state of continuous deformation, the sealing performance between the axial portion 11 of the elastic sleeve and the axial portion 21 of the machine cover is kept better.

The elastic part 31 can be formed by bending a wire, and the radially outer part 311 and the radially inner part 312 are connected together to form a whole through a connecting part 313, which facilitates setting the elastic part 31 to the sealing part 32 during the rubber vulcanization process. Inside the rubber material, the processing cost is low.

The distal ends of the radially outer portion 311 and the radially inner portion 312 may be arc-shaped formed by bending a metal wire, and the circumferential dimensions of the distal ends of the radially outer portion 311 and the radially inner portion 312 are relatively small, namely The circumferential dimension of the distal ends of the radially outer portion 311 and the radially inner portion 312 is smaller than that of the base portion (the part connected to the connecting portion 313 ), so as to flexibly respond to the deformation of the elastic sleeve 1 . In response to the irregular radial deformation of the elastic sleeve 1, the degree of deformation of the plurality of radially outer portions 311 and the plurality of radially inner portions 312 can be different, so that the sealing portion 32 can flexibly follow the radial dimension of the elastic sleeve 1 Changes to maintain better sealing performance.

It can be understood that the metal wire can be very thin. In the case that the material of the metal wire is the same as the structure of the elastic part 31, the thinner the metal wire, the better the flexibility of the elastic part 31, and the sealing part 32 can flexibly follow the shape of the elastic sleeve. The radial dimension changes. As the radial dimension of the elastic sleeve 1 changes randomly, the first sealing lip 33 can maintain a good seal with the swing of the elastic sleeve 1 .

When the sealing ring 3 is installed between the axial part 11 of the elastic sleeve and the axial part 21 of the machine cover, the first sealing lip 33 and the second sealing lip 34 are squeezed and close to each other, and the first sealing lip 33 and the The axial part 11 of the elastic sleeve is interference fit, and the second sealing lip 34 is interference fit with the axial part 21 of the machine cover. And the elastic part 31 is compressed and deformed, and the elastic part 31 can strengthen the elastic force in the radial direction so that the first sealing lip 33 and the second sealing lip 34 tend to move away from each other in the radial direction R. Furthermore, the first sealing lip 33 is more closely attached to the axial portion 11 of the elastic sleeve, and the second sealing lip 34 is more closely attached to the axial portion 21 of the machine cover, and the first sealing lip 33 can respond to the axial portion of the elastic sleeve. The radial deformation of 11 prevents, for example, lubricating oil from entering the cavity 4 through the gap, so that the sealing effect of the sealing ring 3 is better.

Certainly, the present invention is not limited to the above-mentioned embodiments, and those skilled in the art can make various modifications to the above-mentioned embodiments of the present invention under the teaching of the present invention without departing from the scope of the present invention.

(i) In the above embodiment, the elastic part 31 is a continuous whole in the circumferential direction, but the present invention is not limited thereto, and the elastic part may also be a plurality of spaced apart in the circumferential direction.

(ii) It can be understood that the elastic part may not be in the shape of a bent wire, but in the shape of a bent belt or a ring with a V-shaped or U-shaped cross section.

For example, the elastic part can be punched out of a thin metal sheet, so that the elastic part made of the metal sheet has substantially the same overall shape as the above-mentioned elastic part 31 . A plurality of slots or openings or holes can be formed in the metal sheet to allow better flexibility of the elastic part.

For example, the above-mentioned elastic portion can be formed by connecting a plurality of U-shaped or V-shaped metal wires or metal sheets into a ring shape by using connectors such as rubber and metal wires.

Although the present invention has been described in detail using the above-mentioned embodiments, it is obvious to those skilled in the art that the present invention is not limited to the embodiments described in this specification. The present invention can be modified and implemented as modified embodiments without departing from the spirit and scope of the present invention defined by the claims. Therefore, the description in this specification is for the purpose of illustration and does not have any restrictive meaning to the present invention.

List of reference signs

10 elastic sleeve 20 machine cover 30 sealing ring 40 cavity

1 elastic sleeve 11 axial part of elastic sleeve 12 radial part of elastic sleeve

2 machine cover 21 machine cover axial part 22 machine cover radial part 23 ring groove

3 sealing ring 31 elastic part 311 radial outer part 312 radial inner part 32 sealing part 33 first sealing lip 34 second sealing lip 35 connecting section

4 cavities

A axial R radial C circumferential.

Claims

A sealing ring, characterized in that it comprises:

A sealing part (32), the sealing part (32) is annular, and the sealing part (32) includes a first sealing lip (33), a second sealing lip (34) and a connecting section (35), the first A sealing lip (33) is located on the radially outer side of the second sealing lip (34), and the first sealing lip (33) and the second sealing lip (34) are connected by the connecting section (35) Together, the first sealing lip (33) is elastically deformable relative to the second sealing lip (34) in the radial direction (R) of the sealing ring; and

An elastic portion (31), the elastic portion (31) comprising a radially outer portion (311) and a radially inner portion (312), the radially outer portion (311) being connected to the first sealing lip (33) , the radially inner portion (312) is connected to the second sealing lip (34),

In the state where the radially outer portion (311) and the radially inner portion (312) are compressed in the radial direction (R) of the sealing ring and approach each other, the elastic portion (31) makes the The first sealing lip (33) and said second sealing lip (34) have a tendency to move away from each other.
The sealing ring according to claim 1, characterized in that, a plurality of said radially outer parts (311) are provided along the circumferential direction (C) of the sealing ring, and along the circumferential direction (C) of the sealing ring A plurality of said radially inner portions (312) are provided.
The sealing ring according to claim 1, characterized in that, the elastic part (31) is formed by bending a metal wire, and the elastic part (31) is wrapped inside the sealing part (32), or the The elastic part (31) is arranged on the inner surface of the sealing part (32).
The sealing ring according to claim 1, characterized in that, the elastic part (31) is stamped from a metal sheet, and the metal sheet has a plurality of grooves or holes or openings therein.
The sealing ring according to claim 1, characterized in that, the radially outer parts (311) and the radially inner parts (312) are arranged alternately in the circumferential direction (C) of the sealing ring, two There is one radially inner portion (312) between the radially outer portions (311), and one radially outer portion (311) between the two radially inner portions (312).
The sealing ring according to claim 1, characterized in that, the elastic portion (31) is cut along the axial direction (A) of the elastic portion (31), and the elastic portion (31) is cut along the circumferential direction (C) of the elastic portion (31). ) observation, the end of the elastic portion (31) is U-shaped or V-shaped.
The sealing ring according to claim 1, characterized in that, the surfaces of the first sealing lip (33) and the second sealing lip (34) are both conical surfaces.
The sealing ring according to claim 1, characterized in that the number of the radially outer portion (311) and the radially inner portion (312) is greater than or equal to 40.
A harmonic reducer, characterized by comprising the sealing ring (3) according to any one of claims 1-8.
The harmonic reducer according to claim 9, characterized in that, the harmonic reducer also includes an elastic sleeve (1) and a machine cover (2), and the sealing ring (3) is located on the elastic sleeve between (1) and the cover (2),

The outer peripheral surface of the machine cover (2) is provided with an annular groove (23) for positioning the sealing ring (3), and the shaft of the contact part between the first sealing lip (33) and the elastic sleeve (1) The axial length is greater than or equal to half of the axial length of the ring groove (23).