WO2022193062A1

WO2022193062A1 - Pressure relief component, gearbox and robot

Info

Publication number: WO2022193062A1
Application number: PCT/CN2021/080765
Authority: WO
Inventors: Xinguo FU; Mao Li; Tao Feng
Original assignee: Abb Schweiz Ag
Priority date: 2021-03-15
Filing date: 2021-03-15
Publication date: 2022-09-22
Also published as: CN116887952A

Abstract

A pressure relief component (100) for a gearbox (200), comprising: a gas-permeable film (101) arranged adjacent to an internal chamber (201) of the gearbox (200) for receiving lubricant and adapted to allow passage of gas but prevent passage of the lubricant; and a fixing member (102) arranged on a side of the gas-permeable film (101) away from the internal chamber (201) to hermetically fix the gas-permeable film (101) in position, the fixing member (102) comprising a through hole (1023) for the gas passing through the gas-permeable film (101) from the internal chamber (201) to escape. With the pressure relief component (100) comprising the gas-permeable film (101) and the fixing member (102), during the operation of a gearbox (200), gas within the internal chamber (201) can pass through the gas-permeable film (101) and escape to the external environment. In this way, the pressure within the internal chamber (201) can be maintained at a relatively low level. This ensures the sealing system of the gearbox (200) works within a safe pressure range, thereby ensuring the effectiveness of the sealing system and improving the reliability of the gearbox (200).The disclosure also provides a gearbox (200) and a robot.

Description

PRESSURE RELIEF COMPONENT, GEARBOX AND ROBOT

FIELD

Embodiments of the present disclosure generally relate to a gearbox of a robot, and more specifically, to a pressure relief component for a gearbox.

BACKGROUND

Robots are widely-used automation mechanisms that increase operational efficiency and accuracy. A robot typically comprises robot arm links and joints. The robot arm link can be driven to rotate or move by a motor arranged in the joint or a base. To meet reduction ratio requirements, a gearbox or a reducer needs to be arranged between the motor and the robot arm links to be driven. The gearbox is a device that uses gears and gear trains to provide speed and torque conversions from a rotating power source to another device.

Lubricant such as oil and/or grease is usually provided in the gearbox to provide lubrication for the gears and other components. Besides the lubrication function for the individual elements to substantially reduce friction, lubricant in the gearbox can also cool the heated subassemblies as well as mitigate and attenuate gear strokes. In addition, it reduces vibration, protects against corrosion, and keeps everything clean. Lubricant is usually located in an internal chamber of the gearbox to provide lubrication to the various components around the internal chamber. Lubricant usually fills roughly half of the internal chamber.

SUMMARY

Embodiments of the present disclosure provide a pressure relief component for a gearbox, an associated gearbox and a robot.

In a first aspect, a pressure relief component for a gearbox is provided. The pressure relief component comprises a gas-permeable film arranged adjacent to an internal chamber of the gearbox for receiving lubricant and adapted to allow passage of gas but prevent passage of the lubricant; and a fixing member arranged on a side of the gas-permeable film away from the internal chamber to hermetically fix the gas-permeable film in position, the fixing member comprising a through hole for the gas passing through the gas-permeable film from the internal chamber to escape.

With the pressure relief component comprising the gas-permeable film and the fixing member according to embodiments of the present disclosure, during the operation of a gearbox, gas within the internal chamber can pass through the gas-permeable film and escape to the external environment. In this way, the pressure within the internal chamber can be maintained at a relatively low level. This ensures the sealing system of the gearbox works within a safe pressure range, thereby ensuring the effectiveness of the sealing system and improving the reliability of the gearbox.

In some embodiments, the pressure relief component is arranged in a coupling hole of an end part of the gearbox for closing the internal chamber. In this way, the pressure relief component can be assembled to the gearbox in a simple way.

In some embodiments, the fixing member comprises a coupling portion adapted to be coupled to the coupling hole by a tight fit or bonding. As a result, the pressure relief component can be assembled in the coupling hole easily.

In some embodiments, the coupling portion is adapted to press the gas-permeable film towards a coupling ring of the end part formed at an end of the coupling hole adjacent to the internal chamber, so as to fix the gas-permeable film between the coupling portion and the coupling ring. The gas-permeable film can be hermetically fixed in position with a simple structure.

In some embodiments, the fixing member further comprises a protecting plate arranged at an end of the coupling portion away from the internal chamber and comprising an outer surface flush with a surface of the end part, and wherein the through hole is formed on the protecting plate. The protecting plate can protect the gas-permeable film from being damaged, thereby improving the reliability of the pressure relief component.

In some embodiments, the gas-permeable film is made of an oleophobic material. This arrangement can prevent lubricant from adhering to the gas-permeable film and affecting the air permeability of the gas-permeable film, thereby further improving the reliability of the pressure relief component.

In a second aspect of the present disclosure, a gearbox is provided. The gearbox comprises a housing at least partially surrounding an internal chamber for receiving lubricant; an end part coupled to the housing to close the internal chamber and comprising at least one coupling hole; and at least one pressure relief component according to the first aspect as mentioned above and arranged in the at least one coupling hole.

In some embodiments, the end part comprises at least one coupling ring formed at an end of the coupling hole adjacent to the internal chamber to stop the pressure relief component and prevent the lubricant from leaking between the pressure relief component and the coupling ring.

In some embodiments, the end part is an input or output flange of the gearbox or at least a part of a robot arm.

In a third aspect of the present disclosure, a robot is provided. The robot comprises at least one robot arm coupled to the gearbox as mentioned in the above second aspect.

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 of the present disclosure will become easily comprehensible through the description below.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objectives, features and advantages of the present disclosure will become more apparent through more detailed depiction of example embodiments of the present disclosure in conjunction with the accompanying drawings, wherein in the example embodiments of the present disclosure, same reference numerals usually represent the same components.

FIG. 1 shows a partial perspective view of a gearbox according to embodiments of the present disclosure;

FIG. 2 shows an enlarged view of part A as shown in FIG. 1; and

FIG. 3 shows a partial perspective view of an end part of a gearbox with a pressure relief component according to embodiments of the present disclosure.

Throughout the drawings, the same or similar reference symbols are used to indicate the same or similar elements.

DETAILED DESCRIPTION

The present disclosure will now be discussed with reference to several example embodiments. It is to be understood these embodiments are discussed only for the purpose of enabling those skilled persons in the art to better understand and thus implement the present disclosure, rather than suggesting any limitations on the scope of the subject matter.

As used herein, the term “comprises” and its variants are to be read as open terms that mean “comprises, but is not limited to. ” The term “based on” is to be read as “based at least in part on. ” The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” The terms “first, ” “second, ” and the like may refer to different or same objects. Other definitions, explicit and implicit, may be comprised below. A definition of a term is consistent throughout the description unless the context clearly indicates otherwise.

Various parts such as gears and bearings in a gearbox need lubricant to ensure the smooth and reliable operation of the gearbox. Lubricant used for the gearbox is usually located in an internal chamber inside the gearbox and occupies roughly half of the volume of the internal chamber, while the other half is occupied by air. The internal chamber is typically enclosed by a housing for receiving gears and bearings and end part (s) arranged at one or both ends of the housing. The end parts may be an end flange or a part of a robot arm coupled to the gearbox. During the operation of a gearbox, due to factors such as friction between the various components, the temperature in the lubricant and the components will increase, which will increase the volume of the lubricant and air, resulting in an increased pressure in the internal chamber.

The increased pressure will deteriorate the sealing system of the gearbox used for the internal chamber. For example, under normal circumstances, the pressure that the sealing system can withstand is a predetermined value or range. When the pressure of the internal chamber is greater than this value or range, the sealing system may fail, causing lubricant to leak out and thus causing a series of serious problems.

In order to at least partially address the above and other potential problems, embodiments of the present disclosure provide a pressure relief component 100 for a gearbox 200 to efficiently reduce the pressure within the internal chamber 201 during the operation of the gearbox 200, thereby improving the sealing performance of the gearbox 200. Now some example embodiments will be described with reference to FIGs. 1-3.

FIG. 1 shows a partial perspective view of a gearbox 200 with a pressure relief component 100 according to embodiments of the present disclosure and FIG. 2 shows an enlarged view of part A as shown in FIG. 1. As shown in FIGs. 1 and 2, the pressure relief component 100 generally comprises a gas-permeable film 101 and a fixing member 102 for hermetically fixing the gas-permeable film 101 in position. “Hermetically fixing” means that it is hermetical or airtight between a circumferential edge of the gas-permeable film 101 and the parts where the gas-permeable film 101 is to be fixed, to prevent lubricant leakage therefrom. The gas-permeable film 101 is a kind of film or membrane that can allow gas to pass through but prevent water or lubricant such as oil or grease from passing through.

The fixing member 102 is arranged on a side of the gas-permeable film 101 away from the internal chamber 201 to hermetically fix the gas-permeable film 101 in position, i.e., adjacent to the internal chamber 201. The fixing member 102 comprises a through hole 1023 for gas passing through the gas-permeable film 101 from the internal chamber 201 to escape.

With the pressure relief component 100 comprising the gas-permeable film 101 and the fixing member 102 according to embodiments of the present disclosure, during the operation of a gearbox 200, gas within the internal chamber 201 can pass through the gas-permeable film 101 and escape to the external environment. In this way, the pressure within the internal chamber 201 can be maintained at a relatively low level. This ensures that the sealing system of the gearbox 200 can always work within a safe pressure range, thereby ensuring the effectiveness of the sealing system and improving the reliability of the gearbox 200.

Further, the pressure relief component 100 according to embodiments of the present disclosure may also be applied to various types of gearboxes 200, such as hat-type or cup-type gearboxes 200. In addition, the pressure relief component 100 according to embodiments of the present disclosure can work no matter which orientation the gearbox 200 is in. That is to say, no matter whether the main shaft of the gearbox 200 is vertical, horizontal or inclined, the pressure relief component 100 can effectively reduce the pressure within the internal chamber 201.

In some embodiments, the pressure relief component 100 may be arranged in an end part 202 of the gearbox 200. The end part 202, which may be an end flange or a part of a robot arm coupled to the gearbox 200, can enclose the internal chamber 201 with the housing 203 at least partially surrounding the internal chamber 201 and a further end part 202.

In the following, embodiments of the present disclosure will be described mainly by taking the end part 202 as an end flange as an example. It is to be understood that embodiments where the end part 202 comprises other components such as robot arms are similar, and will not be described separately in the following.

As shown in FIG. 3, the end part 202 may comprise a coupling hole 2021 for receiving the pressure relief component 100. In this way, the pressure relief component 100 may be arranged in an existing gearbox 200 by forming the coupling hole 2021 in the end part 202 of the existing gearbox 200. That is, by making a slight improvement to the existing gearbox 200, the sealing performance of the gearbox 200 can be improved by introducing the pressure relief component 100 according to embodiments, thereby improving the reliability of the gearbox 200 and even the entire robot.

Furthermore, FIGs. 1-3 show that the coupling hole 2021 may be a through hole with a circle shape in cross section in some embodiments. This arrangement can facilitate the forming of the coupling hole 2021 and the assembling of the pressure relief component 100 in the coupling hole 2021. It is to be understood that the coupling hole 2021 formed in the end part 202 may be a through hole with any suitable predetermined shape in cross section, such as a circle, an ellipse, a ring or a polygon shape.

In some embodiments, the coupling hole 2021 may be cylindrical or conical. That is, a diameter of the coupling hole 2021 may be equal in an axial direction or may be gradually reduced from the internal chamber 201 to outside of the end part 202 to form a tapered shape. The tapered shape of the coupling hole 2021 can prevent the pressure relief component 100 from accidentally dropping out during the operation of the gearbox 200 to further improve the reliability of the gearbox 200.

In addition, although FIGs. 1-3 show that there is one coupling hole 2021 and a corresponding pressure relief component 100 arranged in the end part 202, it is to be understood that this is merely illustrative, without suggesting any limitation as to the scope of the present disclosure. Other arrangements or structures are also possible. For example, in some alternative embodiments, there may be a plurality of coupling holes 2021 and corresponding pressure relief components 100, e.g., evenly arranged in the end part 202 in a circumferential direction. This arrangement can further improve the pressure relief capacity of the gearbox 200 with the pressure relief components 100.

In some embodiments, the fixing member 102 may comprise a coupling portion 1021, as shown in FIG. 3. The coupling portion 1021 has a shape corresponding to the predetermined shape of the coupling hole 2021 in cross section to allow the coupling portion 1021 to be coupled to the coupling hole 2021 by a tight fit or bonding, etc.

In some embodiments, the end part 202 may comprise a coupling ring 2022 formed at an end of the coupling hole 2021 adjacent to the internal chamber 201, as shown in FIG. 3. By being coupled to the coupling hole 2021, the coupling portion 1021 can press the gas-permeable film 101 towards the coupling ring 2022, so that the gas-permeable film 101 can be hermetically fixed between the coupling portion 1021 and the coupling ring 2022. In this way, the structure of the end part 202 for receiving the gas-permeable film 101 can be further simplified, thereby improving the material and assembling costs of the end part 202 with the pressure relief component 100.

In some embodiments, the coupling ring 2022 may be a part integrally formed on the end part 202, which may ensure the strength of the end part 202 with the coupling ring 2022. In some alternative embodiments, the coupling ring 2022 may also be a separated part adapted to be assembled on the end of the coupling hole 2021 adjacent to the internal chamber by bonding, welding, fasteners, etc.

In some embodiments, the coupling portion 1021 may have a certain degree of elasticity. On the one hand, the elasticity of the coupling portion 1021 can facilitate the tight fitting of the coupling portion 1021 in the coupling hole 2021. On the other hand, with the elasticity, the coupling portion 1021 may also provide a continuous pressure for the gas-permeable film 101 to prevent lubricant leakage.

To further facilitate the assembling of the pressure relief component 100 in the coupling hole 2021, in some embodiments, the fixing member 102 and the gas-permeable film 101 may be assembled together before the pressure relief component 100 is assembled in the coupling hole 2021. For example, in some embodiments, the fixing member 102 and the gas-permeable film 101 may be assembled together by bonding, etc. In this way, the reliability of the pressure relief component 100 may be further improved while simplifying the assembling of the pressure relief component 100.

In some embodiments, the fixing member 102 may further comprise a protecting plate 1022 arranged at an end of the coupling portion 1021 away from the internal chamber 201 to protect the gas-permeable film 101 from damage. The through hole 1023, which is for gas passing through the gas-permeable film 101 from the internal chamber 201 to escape as mentioned above, may be formed in the protecting plate 1022, as shown in FIG. 3. This arrangement can ensure that gas escapes through the through hole 1023 smoothly while preventing the gas-permeable film 101 from damage.

The protecting plate 1022 may be arranged in the coupling hole 2021 with an outer surface thereof flush with a surface of the end part 202 in some embodiments. This can reduce the risk of interference with other components and improve applicability. Furthermore, in some embodiments, the protecting plate 1022 and the coupling portion 1021 may be integrally made of suitable material such as rubber or silicon, etc., which allows the fixing member 102 to be manufactured in a cost-efficient way.

In some embodiments, the gas-permeable film 101 may be made of an oleophobic material to prevent lubricant such as oil or grease from adhering to the surface of the gas-permeable film 101 and affecting the gas-permeable performance.

In some embodiments, the gas-permeable film 101 may also be deformable. For example, the gas-permeable film 101 can deform when there is pressure difference between the internal chamber 201 and external environment. On the one hand, the deformed gas-permeable film 101 can enlarge the gas-permeable area thereof and thus improve the gas-permeable capacity. On the other hand, the deformed gas-permeable film 101 can enlarge the volume of the internal chamber 201, and thus further reducing the pressure within the internal chamber 201. Furthermore, when the pressure within the internal chamber 201 is substantially equal to the pressure of the external environment, the gas-permeable film 101 may return to its original shape.

Furthermore, FIGs. 1-3 show that the initial shape of the gas-permeable film 101 before deformation may be a flat shape. It is to be understood that this is merely for illustration, without suggesting any limitation as to the scope of the present disclosure. Any other suitable structure or arrangement of the gas-permeable film 101 is also possible. In some embodiments, the gas-permeable film 101 may be of any suitable initial shape, which may be selected from a group consisting of the following: a flat shape, a curved shape, a zigzag shape or a rectangular shape, etc.

According to other aspects of the present disclosure, a gearbox 200 comprising the pressure relief component 100 as mentioned above and a robot comprising the gearbox 200 are provided. As mentioned above, besides the pressure relief component 100 according to embodiments of the present disclosure, the gearbox 200 further comprises a housing 203 at least partially surrounding the internal chamber 201 and an end part 202 coupled to the housing 203 to close the internal chamber 201. The end part 202, which may be an end flange or a part of a robot arm coupled to the gearbox 200, comprises at least one coupling hole 2021 for receiving the pressure relief component 100.

With the end part 202 comprising the pressure relief component 100 according to embodiments of the present disclosure, the pressure within the internal chamber 201 can be maintained at a relatively low level, thereby ensuring that the sealing system of the gearbox 200 can always work within a safe pressure range, and thus ensuring the effectiveness of the sealing system and improving the reliability of the gearbox 200.

In some embodiments, the end part 202 may comprise the at least one coupling ring 2022 formed at an end of the coupling hole 2021 adjacent to the internal chamber 201, as mentioned above, to stop the pressure relief component 100 and prevent lubricant leakage. In this way, the coupling portion 1021 can hermetically fix the air-permeable film between the coupling portion 1021 and the coupling ring 2022.

The robot comprises at least one robot arm coupled to the gearbox 200 as mentioned above. With the pressure relief component 100 according to embodiments of the present disclosure, the sealing performance of the gearbox 200 can be significantly improved and thus prolong the service life of the gearbox 200 and the robot.

It should be appreciated that the above detailed embodiments of the present disclosure are only for exemplifying or explaining principles of the present disclosure and do not limit the present disclosure. Therefore, any modifications, equivalent alternatives and improvements, etc. without departing from the spirit and scope of the present disclosure shall be comprised in the scope of protection of the present disclosure. Meanwhile, appended claims of the present disclosure aim to cover all the variations and modifications falling under the scope and boundary of the claims or equivalents of the scope and boundary.

Claims

A pressure relief component (100) for a gearbox (200) , comprising:

a gas-permeable film (101) arranged adjacent to an internal chamber (201) of the gearbox (200) for receiving lubricant and adapted to allow passage of gas but prevent passage of the lubricant; and

a fixing member (102) arranged on a side of the gas-permeable film (101) away from the internal chamber (201) to hermetically fix the gas-permeable film (101) in position, the fixing member (102) comprising a through hole (1023) for the gas passing through the gas-permeable film (101) from the internal chamber (201) to escape.
The pressure relief component (100) of claim 1, wherein the pressure relief component (100) is arranged in a coupling hole (2021) of an end part (202) of the gearbox (200) for closing the internal chamber (201) .
The pressure relief component (100) of claim 2, wherein the fixing member (102) comprises:

a coupling portion (1021) adapted to be coupled to the coupling hole (2021) by a tight fit or bonding.
The pressure relief component (100) of claim 3, wherein the coupling portion (1021) adapted to press the gas-permeable film (101) towards a coupling ring (2022) of the end part (2021) formed at an end of the coupling hole (2021) adjacent to the internal chamber (201) , so as to fix the gas-permeable film (101) between the coupling portion (1021) and the coupling ring (2022) .
The pressure relief component (100) of claim 3, wherein the fixing member (102) further comprises:

a protecting plate (1022) arranged at an end of the coupling portion (1021) away from the internal chamber (201) and comprising an outer surface flush with a surface of the end part (202) , and

wherein the through hole (1023) is formed on the protecting plate (1022) .
The pressure relief component (100) of claim 1, wherein the gas-permeable film (101) is made of an oleophobic material.
A gearbox (200) , comprising:

a housing (203) at least partially surrounding an internal chamber (201) for receiving lubricant;

an end part (202) coupled to the housing (203) to close the internal chamber (201) and comprising at least one coupling hole (2021) ; and

at least one pressure relief component (100) of any of claims 1-6 arranged in the at least one coupling hole (2021) .
The gearbox (200) of claim 7, wherein the end part (202) comprises:

at least one coupling ring (2022) formed at an end of the coupling hole (2021) adjacent to the internal chamber (201) to stop the pressure relief component (100) and prevent the lubricant from leaking between the pressure relief component (100) and the coupling ring (2022) .
The gearbox (200) of claim 7, wherein the end part (202) is an input or output flange of the gearbox (200) or at least a part of a robot arm.
A robot, comprising at least one robot arm coupled to a gearbox (200) of any of claims 7-9.