Sealing structure for a robot joint and robot joint comprising the sealing structure

Abstract

A sealing structure for a robot joint (1000) and a robot joint (1000) are provided. The sealing structure includes a first sealing member (300) adapted to be connected to a first part (100) of the robot joint (1000), and a second sealing member (400) adapted to be arranged between the first sealing member (300) and a second part (200) of the robot joint (1000) and in contact with the first sealing member (300). The first part (100) is rotatable relative to the second part (200). The material of the first sealing member (300) is harder than the material of the second sealing member (400). The robot joint (1000) includes the sealing structure. With this sealing structure, the speed reducer (500) is tightly sealed from the surrounding environment. In this way, even in harsh conditions, leakage of the speed reducer (500) can be prevented for a long time, so that the service life of the robot joint can be prolonged.

Description

TECHNICAL FIELD

[0001] Embodiments of the present disclosure relate to a sealing structure for a robot joint, and to a robot joint comprising such a sealing structure. BACKGROUND

[0002] Robots are increasingly used in many different applications. A robot requires one or more robot joints to perform a desired action. To this end, a reduction gear is required at the robot joint as one of the most expensive components of the robot joint. The durability of the reduction gear largely determines the service life of the robot joint. SUMMARY

[0003] A sealing structure for a robot joint is presented herein, which is capable of improving the sealing of its reduction gear, thereby reducing the leakage from the reduction gear, and thus prolonging the service life of the robot joint.

[0004] In a first aspect, a sealing structure for a robot joint is presented. The sealing structure comprises a first sealing member and a second sealing member. The first sealing member is adapted to be connected to a first part of the robot joint, while the second sealing member is adapted to be arranged between the first sealing member and a second part of the robot joint. The second sealing member is in contact with the first sealing member when arranged between the first sealing member and the second part of the robot joint. The first part is rotatable relative to the second part. The material of the first sealing member is harder than the material of the second sealing member.

[0005] According to embodiments of the present disclosure, the presented sealing structure forms a durable seal of the space for accommodating a reduction gear in a robot joint, even in harsh environments.

[0006] In some embodiments, the first sealing member of the sealing structure can be made of a material that is resistant to wear and corrosion. In this case, the first sealing member does not rust or get worn out, thereby preventing the generation of abrasive particles or other debris, such as rust.

[0007] In some embodiments, the first sealing member of the sealing structure can be made of stainless steel or electroplated metal. In this way, the first sealing member can be easily machined into any desired profile.

[0008] In some embodiments, the first sealing member of the sealing structure can comprise an arm, and the second sealing member is adapted to be arranged on the arm. Such an arm can provide a suitable surface for the second sealing member to rest on. Thus, the second sealing member can be located on a surface other than the outer circumferential surface of the first sealing member, thereby reducing the radial dimension of the sealing structure.

[0009] In some embodiments, the first sealing member of the sealing structure can further comprise an annular rib, and the annular rib and the arm are provided on opposite ends of the first sealing member. The annular rib can be accommodated in a corresponding annular groove formed in the first part of the robot joint, thereby sealing a gap between the first sealing member and the first part of the robot joint.

[0010] In some embodiments, the first sealing member of the sealing structure can comprise a stepped sealing ring. In this way, the first sealing member can be easily connected to the first part of the robot joint by a press fit.

[0011] In some embodiments, the first sealing member of the sealing structure can comprise an annular sealing ring. In this case, the second sealing member of the sealing structure can be arranged on an outer circumferential surface of the annular sealing ring. In this way, the axial dimension of the resulting sealing structure can be reduced.

[0012] In a second aspect, a robot joint is presented. The robot joint comprises a sealing structure according to any embodiment of the present application. Such a robot joint can be effectively operated for a long time even in a harsh environment. The reduction gear is well sealed from the surrounding environment, thus greatly preventing leakage of the reduction gear.

[0013] It is to be understood that the summary is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features, details, and advantages of the present disclosure will become readily apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0014] The above and other objects, features and advantages of the present disclosure will become more apparent from the following description when taken in conjunction with the accompanying drawings, in which like reference characters designate the same parts throughout the drawings.

[0015] Figure 1 is a schematic cross-sectional view of a robot joint with a sealing structure according to another exemplary embodiment of the present disclosure;

[0016] Figure 2 is a schematic cross-sectional view of a robot joint with a sealing structure according to another exemplary embodiment of the present disclosure;

[0017] Figure 3 is a schematic cross-sectional view of a robot joint with a sealing structure according to another exemplary embodiment of the present disclosure; and

[0018] Figure 4 is a schematic cross-sectional view of a robot joint with a sealing structure according to another exemplary embodiment of the present disclosure.

[0019] Throughout the drawings, identical or similar reference numerals are used to designate identical or similar elements. DETAILED DESCRIPTION

[0020] Over time, the requirements for robots have increased. Most of the complaints from customers are about leakage of the reducer. Unfortunately, some harsh environments even accelerate the leakage. For example, in the case where cleaning of the robot requires use of cleaning fluid, the cleaning fluid degrades the seal of the reducer; in the grinding application environment, water containing fine abrasive particles splashes onto the joint, accelerating the wear of the joint; in the machining environment, cutting fluid corrodes the seal of the reducer; in some relatively dirty environments, excessive dust accelerates the wear of the seal of the reducer. In some sensitive environments, such as clean rooms or sanitary sites, the consumer is more concerned about the pollution caused by the oil leaking out of the robot.

[0021] Traditionally, in order to prevent leakage of the reducer, a sealing structure for the space of the reducer in the joint of the robot has been provided, which typically employs a slit seal or one single sealing member, thereby attempting to isolate the space of the reducer from the surrounding environment. Such a sealing structure can be unreliable in some cases. Recently, a sealing structure employing two spaced-apart sealing members has been provided. Such a sealing structure has a better sealing effect than the sealing structure using a slit seal or one single sealing member. However, it performs poorly in relatively harsh environments.

[0022] To address the above and potential other issues, the present inventor herein proposes an improved sealing structure that can provide a better sealing effect for an extended period of time even in harsh environments compared to the existing sealing structures. Such an improved sealing structure is structurally different from the existing sealing structures, which at least partly contributes to its improved sealing effect.

[0023] The spirit and principles of the present disclosure will now be discussed in detail with reference to several example embodiments. It should be understood that the discussion of these embodiments is merely meant to enable those of ordinary skill in the art to better understand and hence practice the present disclosure, and is not meant to imply any limitation on the scope of the subject matter.

[0024] As used herein, the term "includes" and its variants are to be read to be analogous to an open term that means "comprising, but not limited to." The term "based on" is to be understood as "based, at least in part, on." The terms "one embodiment" and "an embodiment" are to be understood as "at least one embodiment." The term "another embodiment" is to be understood as "at least one other embodiment." The terms "a first," "a second," etc. can refer to different or the same objects. Other explicit and implicit definitions can be included below. The definition of the term is consistent throughout the specification unless the context clearly dictates otherwise.

[0025] As Figure 1 shown, a reducer 500 is disposed at the robot joint 1000 to allow a first portion 100 of the robot joint 1000 to rotate in a desired manner relative to a second portion 200 of the robot joint 1000. The reducer 500 is housed in a space enclosed by the first portion 100 and the second portion 200. In some embodiments, the first portion 100 can be a base of the robot joint 1000, and the second portion 200 can be a housing of the robot joint 1000, or vice versa. In some embodiments, the first portion 100 can be a turret, and the second portion 200 can be an arm driven to rotate relative to the turret, or vice versa.

[0026] Figure 1 A schematic cross-sectional view of a robot joint 1000 having a sealing structure according to an embodiment of the present disclosure is shown. A first sealing member 300 is connected to the first portion 100. The first sealing member 300 can be connected to the first portion 100 by any suitable means, such as screws, glue, press fit, etc. In the embodiment shown, the first sealing member 300 is connected by screws. In some embodiments, the first sealing member 300 can be connected to the second portion 200 instead of the first portion 100. Figure 1

[0027] In some embodiments, the first sealing member 300 can be implemented as a sealing ring. In the embodiment shown, the first sealing member 300 has an annular rib 304 housed in a corresponding groove formed in the first portion 100. The annular rib 304 can facilitate pre-positioning of the first sealing member 300 and sealing of the gap between the first portion 100 and the first sealing member 300. In some embodiments, the first sealing member 300 can be formed without the annular rib 304, and the first portion 100 can be correspondingly formed without the corresponding groove at this time. Figure 1

[0028] In some embodiments, an optional O-ring 600 is provided between the bottom of the groove and the first sealing member 300 to help seal the gap between the first portion 100 and the first sealing member 300. In some embodiments, in addition to or as an alternative to the O-ring 600, the gap between the first sealing member 300 and the first portion 100 can be sealed in other ways, such as by using a gasket or glue.

[0029] Also as Figure 1 ​​As shown, the first sealing member 300 has a protruding arm 302 on an end of the first sealing member 300 opposite the rib 304. The arm 302 and the rib 304 extend in opposite directions. The arm 302 extends longitudinally and provides a surface on which a second sealing member 400 can be disposed. The second sealing member 400 can be any seal suitable for a rotational seal, such as an oil seal, a pan plug seal / variseal, a Glyd-ring / lattice ring, a v-ring, etc. The material of the second sealing member 400 is softer than the material of the first sealing member 300. In other words, the first sealing member 300 is made of a material that is harder than the material of the second sealing member 400.

[0030] The second sealing member 400 is disposed on the surface of the protruding arm 302 of the first sealing member 300 and in contact with the first sealing member 300. The second part 200 is arranged such that the second part 200 and the arm 302 of the first sealing member 300 sandwich the second sealing member 400. The second part 200 can be mounted to the first part 100 in a conventional manner. In this way, the first sealing member 300 and the second sealing member 400 form a sealing structure that tightly seals the space between the first part 100 and the second part 200 that houses the speed reducer 500. By arranging the second sealing member 400 on the arm 302, the radial dimension perpendicular to the rotational axis between the first part 100 and the second part 200 of the sealing structure can be reduced.

[0031] The first sealing member 300 can have any suitable cross-section. As Figure 2 shown, the first sealing member 300 can be formed as a stepped ring for press-fitting on the first part 100. In this case, glue can be used to seal the gap between the first part 100 and the first sealing member 300. The sealing ring can be formed without an arm. As Figure 3 and Figure 4 shown, the first sealing member 300 can be formed as a ring-shaped sealing ring and used with different kinds of second sealing members 400 at different robot joints 1000. The second sealing member 400 can be in contact with the first sealing member 300 around the outer circumferential surface of the first sealing member 300. In this way, the axial dimension along the rotational axis between the first part 100 and the second part 200 of the resulting sealing structure can be reduced.

[0032] In some embodiments, the first sealing member 300 is made of a wear- and corrosion-resistant material. In this way, the occurrence of abrasive particles or other debris, such as rust, can be avoided. For example, in some embodiments, the first sealing member 300 is made of stainless steel or galvanized metal. This makes the sealing ring easy to machine.

[0033] With the sealing structure according to the embodiment of the disclosure, the space for the reducer is well sealed and protected from the surrounding environment. As a result, even when the robot is used in a harsh environment, the sealing of the reducer itself is protected, thereby preventing oil leakage and thus increasing the service life of the reducer. Since the reducer is one of the most expensive components in the robot joint, extending the service life of the reducer inevitably improves customer satisfaction.

[0034] In addition, the sealing structure according to the present disclosure can also prevent contamination of the external environment due to oil leakage when the robot is used in a clean environment such as a clean room and a sanitary environment. Furthermore, the sealing structure according to the present disclosure can prevent rust on the surface of the reducer or other dirt hidden in the reducer space from contaminating the external environment.

[0035] It should be understood that the above detailed embodiments of the disclosure are provided only to illustrate or explain the principles of the disclosure, not to limit the disclosure. Therefore, any modifications, equivalent replacements and improvements, etc. shall be included in the protection scope of the disclosure without departing from the spirit and scope of the disclosure. At the same time, the appended claims of the disclosure are intended to cover all changes and modifications falling within the scope and limits or scope and limits of the claims.

Claims

1. A sealing structure for a robot joint (1000), comprising: A first sealing member (300) is connected to a first portion (100) of the robot joint (1000). as well as A second sealing member (400) is adapted to be disposed between and in contact with the first sealing member (300) and a second portion (200) of the robot joint (1000), the first portion (100) being rotatable relative to the second portion (200), the second portion (200) being arranged such that the second portion (200) and the first sealing member (300) sandwich the second sealing member (400) in the middle, thereby the first portion (100) and the second portion (200) surrounding a space for accommodating the reducer. The material of the first sealing member (300) is harder than the material of the second sealing member (400).

2. The sealing structure according to claim 1, wherein, The first sealing member (300) is made of wear-resistant and corrosion-resistant material.

3. The sealing structure according to claim 2, wherein, The first sealing member (300) is made of stainless steel or electroplated metal.

4. The sealing structure according to claim 1, wherein, The first sealing member (300) includes an arm (302), and the second sealing member (400) is adapted to be disposed on the arm (302).

5. The sealing structure according to claim 4, wherein, The first sealing member (300) includes an annular rib (304) and the arm (302) are disposed on opposite ends of the first sealing member (300).

6. The sealing structure according to claim 1, wherein, The first sealing member (300) includes a stepped sealing ring.

7. The sealing structure according to claim 1, wherein, The first sealing member (300) includes an annular sealing ring.

8. A robot joint (1000), comprising: The sealing structure according to any one of claims 1-7.

Images