CN116949414A

CN116949414A - Vacuum coating equipment and exhaust system thereof

Info

Publication number: CN116949414A
Application number: CN202311139359.2A
Authority: CN
Inventors: 葛鹤龄; 王怀民; 程序雳; 姜友松
Original assignee: Anhui Qimang Photoelectric Technology Co ltd
Current assignee: Anhui Qimang Photoelectric Technology Co ltd
Priority date: 2023-09-05
Filing date: 2023-09-05
Publication date: 2023-10-27

Abstract

The application discloses a vacuum coating device and an exhaust system thereof, wherein the exhaust system comprises: a cold trap assembly comprising a cold trap body having a cold trap conduit extending helically in an axial direction; a receiving chamber for mounting the cold trap assembly; the cold trap main body is positioned in the accommodating cavity; a communication passage extending in the axial direction, which is communicated with the upstream of the accommodating chamber; the communication channel is provided with a port which is communicated with the accommodating chamber; the vertical projection of the cold trap main body on the plane of the port surrounds the outside of the port; the accommodating chamber is provided with a blocking wall which surrounds the peripheral side of the port and is vertical to the axial direction, and the cold trap main body is blocked and positioned at one side of the blocking wall away from the communication channel; an exhaust pipeline communicated with the accommodating chamber, wherein the inlet is positioned at one side of the accommodating chamber away from the communication channel; the vertical projection of the inlet on the plane of the port is positioned at the inner side of the port; a valve body disposed on the exhaust pipe; and the first pump group is connected to one end of the exhaust pipeline far away from the accommodating chamber. The vacuum coating equipment and the exhaust system thereof provided by the specification can improve the exhaust efficiency.

Description

Vacuum coating equipment and exhaust system thereof

Technical Field

The present disclosure relates to the field of vacuum coating technologies, and in particular, to a vacuum coating apparatus and an exhaust system thereof.

Background

During high vacuum acquisition, the rough evacuation phase typically requires the use of a valve switch to control the start and stop of the evacuation process. The valve is placed on a conduit of the exhaust system between the vacuum chamber and the mechanical pump stack.

In the prior art, valve 10 is typically mounted on top of the exhaust passage, as shown in FIG. 1. However, such an installation has the following significant drawbacks:

1. the exhaust port is not in the range of the exhaust channel, so that the exhaust efficiency is affected; 2. the exhaust line bend affects the exhaust efficiency.

Disclosure of Invention

In view of the shortcomings of the prior art, an object of the present specification is to provide a vacuum coating apparatus and an exhaust system thereof, which can improve exhaust efficiency.

To achieve the above object, embodiments of the present disclosure provide an exhaust system of a vacuum coating apparatus, including:

a cold trap assembly comprising a cold trap body having a cold trap conduit extending helically in an axial direction;

a receiving chamber in which the cold trap assembly is installed; the cold trap body is positioned in the accommodating cavity;

a communication passage for communicating the accommodating chamber and a vacuum chamber of the vacuum plating apparatus, the communication passage extending in the axial direction, the communication passage communicating upstream of the accommodating chamber; the communication channel has a port into the receiving chamber; the vertical projection of the cold trap main body on the plane of the port surrounds the outer side of the port; the accommodating chamber is provided with a blocking wall which surrounds the periphery of the port and is perpendicular to the axial direction, and the cold trap main body is blocked and positioned at one side of the blocking wall away from the communication channel;

an exhaust pipe communicated with the accommodating chamber, wherein an inlet of the exhaust pipe is positioned at one side of the accommodating chamber away from the communication channel; the vertical projection of the inlet on the plane of the port is positioned at the inner side of the port;

the valve body is arranged on the exhaust pipeline and used for controlling the on-off of the exhaust pipeline;

and the first pump group is connected with one end of the exhaust pipeline, which is far away from the accommodating chamber.

As a preferred embodiment, the exhaust duct includes a first pipe body extending in the axial direction, and the valve body is provided on the first pipe body; one end of the first pipe body is the inlet, and the other end of the first pipe body is communicated with the first pump group.

As a preferred embodiment, the exhaust duct includes a second pipe body having an extending direction perpendicular to the axial direction; one end of the second pipe body is connected with one end of the first pipe body, which is far away from the inlet, through a transfer pipe, and the other end of the second pipe body is connected with the first pump set.

As a preferred embodiment, the shape of the port is one of rectangular, circular or elliptical, and the perpendicular projection of the inlet on the plane of the port is arranged near the edge of the port.

As a preferred embodiment, a mounting plate is provided on the side of the receiving chamber facing away from the communication channel, the mounting plate being perpendicular to the axial direction, and the inlet is provided on the mounting plate.

As a preferred embodiment, a second pump set is fixedly mounted on the mounting plate, and the adjusting precision of the second pump set is higher than that of the first pump set.

As a preferred embodiment, the vertical projection of the second pump group on the plane of the port is located inside the port.

As a preferred embodiment, the valve body is one of a gate valve, a ball valve and a butterfly valve.

As a preferred embodiment, the cold trap assembly further comprises a cold trap mounting frame fixedly mounted within the containment chamber carrying the cold trap body; the vertical projection of the cold trap installation frame on the plane of the port surrounds the outer side of the port; the vertical projection of the cold trap body on the plane of the port is positioned between the vertical projection of the cold trap mounting frame and the port.

As a preferred embodiment, the communication passage is located at a side wall of the vacuum chamber, the side wall being perpendicular to the axial direction.

The embodiment also provides vacuum coating equipment, which comprises a vacuum chamber for coating and an exhaust system for exhausting the vacuum chamber, wherein the exhaust system is the exhaust system in any one of the embodiments.

The beneficial effects are that:

the exhaust system of the vacuum coating equipment provided by the embodiment is provided with a containing chamber for containing the cold trap main body, the upstream of the containing chamber is communicated with the vacuum chamber through a communication channel, the containing chamber is also communicated with a first pump set, and the first pump set can exhaust the vacuum chamber. The cold trap main body is not arranged in the vacuum chamber, so that the space of the vacuum chamber can be saved, the cold trap main body is prevented from being polluted, and the energy consumption loss is reduced. The communication channel is provided with a port which is communicated with the accommodating cavity, the vertical projection of the cold trap main body on the plane where the port is located surrounds the outer side of the port, so that when the first pump group exhausts the vacuum cavity, the exhaust channel is formed by the communication channel and the space with the same radial dimension as the port in the accommodating cavity, the cold trap main body cannot occupy the exhaust channel, the cold trap main body is prevented from being polluted, and the exhaust channel is not hindered from improving the exhaust efficiency. Simultaneously, setting up the cold trap main part can reduce the air humidity of exhaust, improves the life-span of first pump package.

And the side of the accommodating cavity, which is away from the communication channel, is provided with an exhaust pipeline, the cold trap assembly is positioned between the exhaust pipelines of the communication channel box, and the vertical projection of the inlet of the exhaust pipeline on the plane of the port is positioned at the inner side of the port, so that when the valve body is opened and the first pump set is used for exhausting the vacuum cavity, the inlet is opposite to the exhaust channel, thereby reducing the exhaust resistance and improving the exhaust efficiency. The overall structure layout of the exhaust system is compact, and the exhaust efficiency can be improved.

Specific embodiments of the application are disclosed in detail below with reference to the following description and drawings, indicating the manner in which the principles of the application may be employed. It should be understood that the embodiments of the application are not limited in scope thereby.

Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments in combination with or instead of the features of the other embodiments.

It should be emphasized that the term "comprises/comprising" when used herein is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps or components.

Drawings

In order to more clearly illustrate the embodiments of the application or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the description below are only some embodiments of the application, and that other drawings can be obtained from these drawings without inventive faculty for a person skilled in the art.

FIG. 1 is a schematic view of a vacuum coating apparatus according to the prior art;

fig. 2 is a schematic structural view of a vacuum coating apparatus provided with an exhaust system according to the present embodiment;

fig. 3 is a left side view of fig. 1, and in partial perspective.

Reference numerals illustrate:

1. a cold trap assembly; 11. a cold trap body; 12. a cold trap mounting frame; 2. a housing chamber; 21. a retaining wall; 3. a communication passage; 31. a port; 4. an exhaust duct; 41. an inlet; 42. a first tube body; 43. a second tube body; 44. a transfer tube; 5. a valve body; 6. a first pump group; 7. a mounting plate; 8. a second pump group; 9. a vacuum chamber; 91. a sidewall; 10. a valve; 81. a first support frame; 82. a second support frame; x, axial direction.

Detailed Description

In order to make the technical solution of the present application better understood by those skilled in the art, the technical solution of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, shall fall within the scope of the application.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

Please refer to fig. 2 and 3. The embodiment of the application provides an exhaust system of vacuum coating equipment, which comprises a cold trap assembly 1, a containing chamber 2, a communication channel 3, an exhaust pipeline 4, a valve body 5 and a first pump group 6.

Wherein the cold trap assembly 1 comprises a cold trap body 11 having a cold trap pipe extending helically in an axial direction X. The accommodating chamber 2 mounts the cold trap assembly 1, and the cold trap body 11 is located within the accommodating chamber 2. The communication channel 3 is used for communicating the accommodating chamber 2 and the vacuum chamber 9 of the vacuum coating equipment. The communication passage 3 extends in the axial direction X, and the communication passage 3 communicates upstream of the accommodating chamber 2. The communication channel 3 has a port 31 opening into the receiving chamber 2. The vertical projection of the cold trap body 11 onto the plane of the port 31 surrounds the outside of the port 31. The accommodation chamber 2 has a blocking wall 21 perpendicular to the axial direction X around the peripheral side of the port 31, and the cold trap body 11 is shielded from being positioned on the side of the blocking wall 21 facing away from the communication channel 3. The blocking wall 21 may make the size of the accommodating chamber 2 larger than the size of the communication channel 3, so as to facilitate the subsequent vertical projection of the cold trap body 11 in the axial direction X to surround the vertical projection outside the communication channel 3 or be located outside the port 31 after the cold trap body 11 is mounted in the accommodating chamber 2.

The exhaust duct 4 communicates with the accommodation chamber 2. The inlet 41 of the exhaust duct 4 is located on the side of the receiving chamber 2 facing away from the communication channel 3. The vertical projection of the inlet 41 on the plane of the port 31 is located inside the port 31. The valve body 5 is arranged on the exhaust pipeline 4 and is used for controlling the on-off of the exhaust pipeline 4. The first pump group 6 is connected to the end of the exhaust conduit 4 remote from the receiving chamber 2.

The exhaust system of the vacuum coating apparatus provided in this embodiment is provided with a housing chamber 2 for housing a cold trap body 11, and the upstream of the housing chamber 2 is communicated with a vacuum chamber 9 through a communication channel 3, the housing chamber 2 is further communicated with a first pump set 6, and the first pump set 6 can exhaust the vacuum chamber 9. The cold trap main body 11 is not arranged in the vacuum chamber 9, so that the space of the vacuum chamber 9 can be saved, the cold trap main body 11 is prevented from being polluted, and the energy consumption loss is reduced. The communication channel 3 is provided with a port 31 which is communicated with the accommodating chamber 2, and the vertical projection of the cold trap main body 11 on the plane of the port 31 surrounds the outer side of the port 31, so that when the first pump set 6 exhausts the vacuum chamber 9, the exhaust channel consists of the communication channel 3 and a space with the same radial dimension as the port 31 in the accommodating chamber 2, and the cold trap main body 11 does not occupy the exhaust channel, thereby avoiding the pollution of the cold trap main body 11 and preventing the exhaust channel from improving the exhaust efficiency. At the same time, the cold trap body 11 is arranged to reduce the air humidity of the exhaust gas and improve the service life of the first pump group 6.

Also, the side of holding the cavity 2 facing away from the communication channel 3 is provided with an exhaust pipe 4, the cold trap assembly 1 is located between the communication channel 3 and the exhaust pipe 4, and the vertical projection of the inlet 41 of the exhaust pipe 4 on the plane of the port 31 is located at the inner side of the port 31, so that when the valve body 5 is opened and the first pump set 6 exhausts the vacuum cavity 9, the inlet 41 is opposite to the exhaust channel, thereby reducing the exhaust resistance and improving the exhaust efficiency. The overall structure layout of the exhaust system is compact, and the exhaust efficiency can be improved.

In the present embodiment, as shown in fig. 2, the exhaust duct 4 includes a first pipe body 42 extending in the axial direction X, and the valve body 5 is provided on the first pipe body 42. One end of the first pipe body 42 is an inlet 41, and the other end is communicated with the first pump group 6. The first pipe body 42 extends along the axial direction X, so that the decrease of the exhaust efficiency caused by a curve can be avoided, the exhaust passage is further increased, and the exhaust resistance is reduced.

Wherein, valve body 5 can be one of push-pull valve, ball valve, butterfly valve. Of course, other structures can be selected for the valve body 5, and the valve body 5 can control the on-off of the linear pipeline only by meeting the requirement. The opening and closing of the valve body 5 controls the on-off of the exhaust pipeline 4, and finally, the starting and ending of the exhaust of the vacuum chamber 9 by the first pump group 6 are realized.

As shown in fig. 2, the exhaust duct 4 further includes a second pipe body 43, and the extending direction of the second pipe body 43 is perpendicular to the axial direction X. One end of the second tube body 43 is connected to one end of the first tube body 42 remote from the inlet 41 through a transfer tube 44, and the other end is connected to the first pump unit 6.

The second pipe body 43 extends downwards, so as to connect the first pipe body 42 with the first pump set 6, the height of the first pump set 6 is not required to be too high, and the height difference between the first pump set 6 and the first pipe body 42 can be compensated by the second pipe body 43, so that the whole structure can be simplified. Preferably, a first supporting frame 81 may be disposed below the first pipe body 42, for supporting the first pipe body 42, so as to avoid the first pipe body 42 from falling, and ensure stable and firm structure of the exhaust pipe 4.

In other embodiments, the connection port of the first pump unit 6 may be disposed on the side, so that the exhaust pipe 4 only includes the first pipe body 42 extending along the axial direction X, and the height of the first pipe body 42 is equivalent to the height of the connection port of the first pump unit 6, so that the end of the first pipe body 42 away from the inlet 41 may be directly connected to the first pump unit 6, so as to maximize the exhaust efficiency.

As shown in fig. 2, the side of the receiving chamber 2 facing away from the communication channel 3 is provided with a mounting plate 7, the mounting plate 7 being perpendicular to the axial direction X, so that the inlet 41 can be provided on the mounting plate 7. The mounting plate 7 is also fixedly provided with a second pump set 8, and the adjusting precision of the second pump set 8 is higher than that of the first pump set 6.

In particular, the second pump group 8 may comprise a molecular pump for drawing a high vacuum. The first pump group 6 may comprise a roughing pump for roughing. The first pump stack 6 and the second pump stack 8 are each used to evacuate the vacuum chamber 9 to ultimately create a vacuum. By providing the cold trap body 11, the lifetime of the first pump group 6 and the second pump group 8 can be extended.

Preferably, the vertical projection of the second pump group 8 on the plane of the port 31 is located inside the port 31, thereby improving the exhaust efficiency of the second pump group 8.

In the present embodiment, the shape of the port 31 is one of rectangular, circular, or elliptical. As shown in fig. 3, the vertical projection of the inlet 41 on the plane of the port 31 is close to the edge of the port 31, so that the position of the second pump set 8 can be well avoided, interference with the second pump set 8 is avoided, the original position of the second pump set 8 is not changed, and the structure can be simplified. For example, the port 31 may be rectangular in shape, and the perpendicular projection of the inlet 41 onto the plane of the port 31 may be disposed near one corner of the rectangle.

In one embodiment, the cold trap assembly 1 further comprises a cold trap mounting frame 12 fixedly mounted within the containment chamber 2 carrying the cold trap body 11. The cold trap installation frame 12 is located between the wall surface of the accommodating chamber 2 and the cold trap body 11, the cold trap body 11 is disposed along the inner wall of the cold trap installation frame 12, and the cold trap installation frame 12 can fix the cold trap body 11 inside the accommodating chamber 2. The vertical projection of the cold trap installation frame 12 on the plane of the port 31 surrounds the outside of the port 31, so that the vertical projection of the cold trap body 11 disposed inside the cold trap installation frame 12 on the plane of the port 31 surrounds the outside of the port 31.

Specifically, the vertical projection of the cold trap body 11 on the plane where the port 31 is located between the vertical projection of the cold trap mounting frame 12 and the port 31, and the cold trap body 11 is located entirely outside the port 31, so that the cold trap body 11 does not obstruct the exhaust passage, the cold trap body 11 is prevented from being polluted, and the exhaust efficiency can be improved. The plane in which the ports 31 lie in this description is perpendicular to the axial direction X.

In order to make the exhaust efficiency higher and to ensure a sufficient installation space for the cold trap body 11, the ratio of the area of the installation port 31 to the area of the vertical projection of the inner wall surface of the cold trap installation frame 12 on the plane of the port 31 is set to 0.5 to 0.8. Preferably, the ratio of the area of the port 31 to the area of the vertical projection of the inner wall surface of the cold trap mounting frame 12 on the plane of the port 31 is 0.7.

In the present embodiment, the vertical projection of the inner wall surface of the cold trap installation frame 12 on the plane on which the port 31 is located is one of rectangular, circular, or elliptical. In one embodiment, the port 31 is a first rectangle and the vertical projection of the inner wall surface of the cold trap mounting frame 12 on the plane of the port 31 is a second rectangle. The ratio of the area of the first rectangle to the area of the second rectangle is 0.5-0.8. Further, the ratio of the area of the first rectangle to the area of the second rectangle is 0.7.

Specifically, in order to make the exhaust efficiency higher and to secure a sufficient installation space for the cold trap body 11, the ratio of the length of the long side of the first rectangle to the length of the long side of the second rectangle is 0.6 to 0.9. Preferably, the ratio of the length of the long side of the first rectangle to the length of the long side of the second rectangle is 0.7 or 0.8. The long sides of the first rectangle and the long sides of the second rectangle may each extend in the horizontal direction.

In the preferred embodiment, the communication passage 3, the cold trap installation frame 12, the installation plate 7 and the exhaust duct 4 are sequentially arranged in the axial direction X, and the extracted gas does not contaminate the cold trap body 11 while the cold trap body 11 is operating normally, and the inlet 41 of the exhaust duct 4 is facing the port 31 of the communication passage 3, so that the exhaust efficiency can be improved.

Preferably, a second supporting frame 82 is arranged below the accommodating chamber 2 and is used for supporting the accommodating chamber 2, so that the accommodating chamber 2 has stronger structural strength.

In the present embodiment, the communication channel 3 is located on the side wall 91 of the vacuum chamber 9, and the side wall 91 is perpendicular to the axial direction X, so that the overall structure is optimized while the coating reaction in the vacuum chamber 9 is not affected. The communication channel 3 extends in the axial direction X, and the radial dimension of the communication channel 3 remains unchanged in the axial direction X, i.e. the radial dimension of the communication channel 3 everywhere is equal to the dimension at the port 31. The cold trap main body 11 is installed in the accommodating chamber 2 in a fully concealed manner, and has the effect of maintenance free as the condition of being polluted is avoided.

Based on the same conception, the embodiment of the application also provides vacuum coating equipment, as described in the following embodiment. Because the principle of solving the problem and the technical effect that can be obtained by the vacuum coating equipment are similar to those of the exhaust system, the implementation of the vacuum coating equipment can be referred to the implementation of the exhaust system, and the repetition is omitted.

One embodiment of the present application also provides a vacuum coating apparatus, including: an exhaust system as in any preceding embodiment. The vacuum coating equipment further comprises a vacuum chamber 9 for coating, and the exhaust system is used for exhausting the vacuum chamber 9.

It should be noted that the vacuum coating apparatus provided in this embodiment may have any suitable existing configuration, such as the vacuum chamber 9, the coating frame, and other parts (e.g., the power part, the control part), etc. For clarity and brevity, the technical solutions provided by the present embodiments will not be repeated here, and the drawings in the description are correspondingly simplified. It should be understood that the present embodiment is not limited in scope thereby.

It should be noted that, in the description of the present specification, the terms "first," "second," and the like are used for descriptive purposes only and to distinguish between similar objects, and there is no order of preference therebetween, nor should it be construed as indicating or implying relative importance. In addition, in the description of the present specification, unless otherwise indicated, the meaning of "a plurality" is two or more.

Any numerical value recited herein includes all values of the lower and upper values that are incremented by one unit from the lower value to the upper value, as long as there is a separation of at least two units between any lower value and any higher value. For example, if it is stated that the number of components or the value of a process variable (e.g., temperature, pressure, time, etc.) is from 1 to 90, preferably from 20 to 80, more preferably from 30 to 70, then the purpose is to explicitly list such values as 15 to 85, 22 to 68, 43 to 51, 30 to 32, etc. in this specification as well. For values less than 1, one unit is suitably considered to be 0.0001, 0.001, 0.01, 0.1. These are merely examples that are intended to be explicitly recited in this description, and all possible combinations of values recited between the lowest value and the highest value are believed to be explicitly stated in the description in a similar manner.

Unless otherwise indicated, all ranges include endpoints and all numbers between endpoints. "about" or "approximately" as used with a range is applicable to both endpoints of the range. Thus, "about 20 to 30" is intended to cover "about 20 to about 30," including at least the indicated endpoints.

All articles and references, including patent applications and publications, disclosed herein are incorporated by reference for all purposes. The term "consisting essentially of …" describing a combination shall include the identified element, ingredient, component or step as well as other elements, ingredients, components or steps that do not substantially affect the essential novel features of the combination. The use of the terms "comprises" or "comprising" to describe combinations of elements, components, or steps herein also contemplates embodiments consisting essentially of such elements, components, or steps. By using the term "may" herein, it is intended that any attribute described as "may" be included is optional.

Multiple elements, components, parts or steps can be provided by a single integrated element, component, part or step. Alternatively, a single integrated element, component, part or step may be divided into separate plural elements, components, parts or steps. The disclosure of "a" or "an" to describe an element, component, section or step is not intended to exclude other elements, components, sections or steps.

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and many applications other than the examples provided will be apparent to those of skill in the art upon reading the above description. The scope of the present teachings should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are incorporated herein by reference for the purpose of completeness. The omission of any aspect of the subject matter disclosed herein in the preceding claims is not intended to forego such subject matter, nor should the inventors regard such subject matter as not be considered to be part of the disclosed subject matter.

Claims

1. An exhaust system of a vacuum coating apparatus, comprising:

2. The exhaust system of claim 1, wherein the exhaust conduit comprises a first tube extending in the axial direction, the valve body being disposed on the first tube; one end of the first pipe body is the inlet, and the other end of the first pipe body is communicated with the first pump group.

3. The exhaust system of claim 2, wherein the exhaust conduit comprises a second tube, the second tube extending in a direction perpendicular to the axial direction; one end of the second pipe body is connected with one end of the first pipe body, which is far away from the inlet, through a transfer pipe, and the other end of the second pipe body is connected with the first pump set.

4. The exhaust system of claim 1, wherein the port is one of rectangular, circular, or oval in shape, and wherein a perpendicular projection of the inlet onto a plane in which the port lies is disposed proximate an edge of the port.

5. The exhaust system according to claim 1, wherein a side of the receiving chamber facing away from the communication channel is provided with a mounting plate, the mounting plate being perpendicular to the axial direction, the inlet being provided on the mounting plate.

6. The exhaust system of claim 5, wherein a second pump set is also fixedly mounted on the mounting plate, the second pump set having a higher adjustment accuracy than the first pump set.

7. The exhaust system of claim 6, wherein a perpendicular projection of the second pump stack onto a plane in which the port lies is located inside the port.

8. The exhaust system of claim 1, wherein the valve body is one of a gate valve, a ball valve, and a butterfly valve.

9. The exhaust system of claim 1, wherein the cold trap assembly further comprises a cold trap mounting frame fixedly mounted within the containment chamber carrying the cold trap body; the vertical projection of the cold trap installation frame on the plane of the port surrounds the outer side of the port; the vertical projection of the cold trap body on the plane of the port is positioned between the vertical projection of the cold trap mounting frame and the port.

10. The exhaust system of claim 1, wherein the communication channel is located at a sidewall of the vacuum chamber, the sidewall being perpendicular to the axial direction.

11. A vacuum coating apparatus comprising a vacuum chamber for coating a film, and an exhaust system for exhausting the vacuum chamber, the exhaust system being as claimed in any one of claims 1 to 10.