WO2018176308A1

WO2018176308A1 - Exhaust apparatus

Info

Publication number: WO2018176308A1
Application number: PCT/CN2017/078736
Authority: WO
Inventors: Qiang LEI; Shena JIA; Hui Wang
Original assignee: Acm Research (Shanghai) Inc.
Priority date: 2017-03-30
Filing date: 2017-03-30
Publication date: 2018-10-04
Also published as: CN110462266A

Abstract

An exhaust apparatus for several kinds of gases separation exhaust is provided. The exhaust apparatus (100) includes an outer pipe (102), an inner pipe (103) and an actuator (104). The outer pipe (102) has a pipe body (1021). A side wall of the pipe body (1021) defines several exhaust ports (1022). The inner pipe (103) is accommodated in the pipe body (1021) of the outer pipe (102). One end of the inner pipe (103) is open and the other end of the inner pipe (103) is sealed. A side wall of the inner pipe (103) defines a through-hole (1033) or a plurality of through-holes (1033). The actuator (104) is configured to drive the inner pipe (103) to rotate in the pipe body (1021) of the outer pipe (102) to make the through-hole (1033) of the inner pipe (103) facing one of the exhaust ports (1022) of the outer pipe (102) for discharging one kind of gas while other exhaust ports (1022) of the outer pipe (102) being blocked by the side wall of the inner pipe (103).

Description

EXHAUST APPARATUS

FIELD OF THE INVENTION

The present invention generally relates to an exhaust apparatus, and more particularly to an improved exhaust apparatus which is applied to several kinds of gases separation exhaust.

BACKGROUND

As we know, the main source of pollution in the semiconductor process is acid gas, alkaline gas, combustible gas, etc. generated during the process of such as etching, cleaning. Because of different treatment methods of acid gas, alkaline gas and combustible gas, therefore, it needs to separately discharge, collect and treat acid gas, alkaline gas and combustible gas. In a conventional semiconductor fabrication apparatus, in order to separately discharge acid gas, alkaline gas and combustible gas, the conventional semiconductor fabrication apparatus generally has three exhaust apparatuses. Every exhaust apparatus is used to discharge one kind of gas. Specifically, every exhaust apparatus has a gas inlet and a gas outlet. The gas inlet of every exhaust apparatus connects to a process chamber and the gas outlet of every exhaust apparatus connects to a facility exhaust system. Corresponding to acid gas, alkaline gas and combustible gas, the facility exhaust system has a facility acid gas exhaust system, a facility alkaline gas exhaust system and a facility combustible gas exhaust system. According to the property of the waste gas (acid gas, alkaline gas and combustible gas) in the process chamber, it needs to select the corresponding exhaust apparatus and the corresponding facility exhaust system.

Although using a plurality of exhaust apparatuses can realize the separation discharge of a plurality of kinds of gases, however, there are still shortcomings. On the one hand, a plurality of exhaust apparatuses occupies a lot of space, leading to the semiconductor fabrication apparatus becoming bloated. On the other hand, when one exhaust apparatus is used, the other exhaust apparatuses are in idle state, resulting in the utilization of exhaust apparatus being reduced. The conventional exhaust apparatuses take up the space and cost, which are obviously not desirable.

SUMMARY

Accordingly, an object of the present invention is to provide an exhaust apparatus for several kinds of gases separation exhaust.

According to one embodiment, an exhaust apparatus includes an outer pipe, an inner pipe and an actuator. The outer pipe has a pipe body. A side wall of the pipe body defines a plurality of exhaust ports. The inner pipe is accommodated in the pipe body of the outer pipe. One end of the inner pipe is open and the other end of the inner pipe is sealed. A side wall of the inner pipe defines a through-hole. The actuator is configured to drive the inner pipe to rotate in the pipe body of the outer pipe to make the through-hole of the inner pipe face one of the exhaust ports of the outer pipe for discharging one kind of gas while other exhaust ports of the outer pipe being blocked by the side wall of the inner pipe.

According to another embodiment, an exhaust apparatus includes an outer pipe, an inner pipe and an actuator. The outer pipe has a pipe body. A side wall of the pipe body defines a plurality of exhaust ports. The inner pipe is accommodated in the pipe body of the outer pipe. One end of the inner pipe is open and the other end of the inner pipe is sealed. A side wall of the inner pipe defines a plurality of through-holes. The actuator is configured to drive the inner pipe to rotate in the pipe body of the outer pipe to make one through-hole of the inner pipe face one exhaust port of the outer pipe for discharging one kind of gas while other exhaust ports of the outer pipe being blocked by the side wall of the inner pipe and other through-holes of the inner pipe being blocked by the side wall of the pipe body of the outer pipe.

As described above, the exhaust apparatus of the present invention realizes several kinds of gases separation exhaust by driving the inner pipe to rotate in the outer pipe to make the through-hole of the inner pipe be facing the corresponding exhaust port of the outer pipe every time. Comparing to conventional exhaust apparatuses, the exhaust apparatus of the present invention not only realizes several kinds of gases separation exhaust but also has a simple structure with low manufacture cost and takes up small space.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary exhaust apparatus according to the present invention.

FIG. 2 is a top view of the exhaust apparatus shown in FIG. 1.

FIG. 3 is a cross-sectional view taken along line A-Ashown in FIG. 2.

FIG. 4 is a perspective view of an outer pipe of the exhaust apparatus.

FIG. 5 is a perspective view of an inner pipe of the exhaust apparatus.

FIG. 6 is another perspective view of the exhaust apparatus.

FIG. 7 is a perspective view of a detected plate of the exhaust apparatus.

FIG. 8 is a perspective view of an outer pipe according to another embodiment of the present invention.

FIG. 9 is a perspective view of an inner pipe according to another embodiment of the present invention.

FIG. 10 is a perspective view of an outer pipe according to another embodiment of the present invention.

FIG. 11 is a perspective view of an inner pipe according to another embodiment of the present invention.

FIG. 12 is a perspective view of an outer pipe according to another embodiment of the present invention.

DETAILED DESCRIPTION

Referring to FIG. 1 to FIG. 3, an exemplary exhaust apparatus according to the present invention is illustrated. The exhaust apparatus 100 includes a gas inlet pipe 101, an outer pipe 102, an inner pipe 103 and an actuator 104. The gas inlet pipe 101 is substantially L-shaped and has a transverse part 1011 and a vertical part 1012. The transverse part 1011 has a gas inlet port 1013. A wall of the transverse part 1011 defines a drain hole 1014 which connects to a drain pipe through a connector105. The vertical part 1012 protrudes outward to form a support part 1015.

The outer pipe 102 is fixed on the support part 1015 of the gas inlet pipe 101. As shown in FIG. 4, the outer pipe 102 has a cylindrical pipe body 1021. A side wall of the pipe body 1021 defines three exhaust ports 1022. The centers of the three exhaust ports 1022 are on the same horizontal plane. It is recognized that the number of the exhaust ports 1022 is not only limited to three. According to the kinds of gases to be discharged, the side wall of the pipe body 1021 defines corresponding numbers of the exhaust ports 1022. For conveniently connecting to a facility exhaust system, every exhaust port 1022 connects to an exhaust pipe 1023. One end of every exhaust pipe 1023 connects to one exhaust port 1022 and the other end of the exhaust pipe 1023 can be connected to the facility exhaust system. Preferably, the size and shape of the three exhaust ports 1022 are uniform.

The inner pipe 103 is accommodated in the pipe body 1021 of the outer pipe 102 and is supported by the support part 1015 of the gas inlet pipe 101. Although a gap is formed between the outer wall of the inner pipe 103 and the inner wall of the pipe body 1021, because the gap is quite small, and moreover, the facility exhaust system is continuously pumping during the process of exhaust, so the possibility of causing gas blow-by is very little. The inner pipe 103 connects to the gas inlet pipe 101. As shown in FIG. 5, the inner pipe 103 is cylindrical. One end of the inner pipe 103 is open and connected to the gas inlet pipe 101, and the other end of the inner pipe 103 is sealed and connected to a connecting shaft 106, as shown in FIG. 3. Specifically, the other end of the inner pipe 103 is sealed by a seal plate 1031. The center of the seal plate 1031 defines an installing groove 1032. One end of the connecting shaft 106 is installed and fixed in the installing groove 1032 of the inner pipe 103. A side wall of the inner pipe 103 defines a through-hole 1033. The through-hole 1033 matches with the exhaust ports 1022 of the outer pipe 102. Preferably, the through-hole 1033 and the exhaust ports 1022 have the same size and shape.

The one end of the connecting shaft 106 is fixed in the installing groove 1032 of the inner pipe 103. The other end of the connecting shaft 106 is fixed in a coupling 107. The coupling 107 connects to the actuator 104. The actuator 104 drives the inner pipe 103 to rotate in the pipe body 1021 of the outer pipe 102 through the coupling 107 and the connecting shaft 106 to make the through-hole 1033 of the inner pipe 103 face one of the exhaust ports 1022 of the outer pipe 102 for discharging one kind of gas. The actuator 104 can be a motor.

The exhaust apparatus 100 has a good seal. Specifically, a first seal ring 108 is set between the outer pipe 102 and the support part 1015 of the gas inlet pipe 101. In addition, a cover plate 109 is fixed on the outer pipe 102. The connecting shaft 106 passes through the center of the cover plate 109. A second seal ring 110 is set between the cover plate 109 and the outer pipe 102. A third seal ring 111 is set between the connecting shaft 106 and the cover plate 109. A fixing ring 112 is set on the third seal ring 111 for positioning the third seal ring 111.

As shown in FIG. 6, the exhaust apparatus 100 further includes four sensors 113. The four sensors 113 are respectively positioned on four support pedestals 114 which are fixed on the cover plate 109 and distributed around the coupling 107. Every two adjacent sensors 113 have an interval therebetween. Preferably, the angle between every two adjacent sensors 113 is 90 degrees. The four sensors 113 can be photoelectric sensors. A detected plate 115 is fixed on the coupling 107 and rotates along with the coupling 107. As shown in FIG. 7, the detected plate 115 is ring-shaped and defines a notch 1151 on an outer edge of the detected plate 115. The four sensors 113 are respectively corresponding to the three exhaust ports 1022 of the outer pipe 102 and an initial position. The notch 1151 of the detected plate 115 is corresponding to the through-hole 1033 of the inner pipe 103. For more clearly illustration, the three exhaust ports 1022 of the outer pipe 102 are respectively marked 1022A, 1022B and 1022C. The three exhaust pipes 1023 are respectively marked 1023A, 1023B and 1023C. The four sensors 113 are respectively marked 113A, 113B, 113C and 113D. The sensor 113A is corresponding to the exhaust port 1022A. The sensor 113B is corresponding to the exhaust port 1022B. The sensor 113C is corresponding to the exhaust port 1022C. The sensor 113D is corresponding to the initial position.

There are at least two methods to detect whether the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022 of the outer pipe 102 before the exhaust. One method is to use the four sensors 113 to detect position coordinates of the three exhaust ports 1022 of the outer pipe 102 and the initial position and record the position coordinates in a software system. Specifically, the actuator 104 drives the coupling 107 to rotate, and the inner pipe 103 and the detected plate 115 rotate along with the coupling 107. When the sensor 113D detects the notch 1151 of the detected plate 115, the software system records the position coordinate of the initial position. When the sensor 113A detects the notch 1151 of the detected plate 115, it indicates that the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022A of the outer pipe 102, and the software system records the position coordinate of the exhaust port 1022A. When the sensor 113B detects the notch 1151 of the detected plate 115, it indicates that the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022B of the outer pipe 102, and the software system records the position coordinate of the exhaust port 1022B. When the sensor 113C detects the notch 1151 of the detected plate 115, it indicates that the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022C of the outer pipe 102, and the software system records the position coordinate of the exhaust port 1022C. After the position coordinates of the three

exhaust ports

1022A, 1022B, 1022C and the initial position are confirmed, if needs to discharge one kind of gas, control the actuator 104 to make the through-hole 1033 of the inner pipe 103 rotate corresponding angle from the initial position and face the corresponding exhaust port 1022 of the outer pipe 102. The other exhaust ports 1022 of the outer pipe 102 are blocked by the side wall of the inner pipe 103.

Another method is to use the sensors 113 to detect the notch 1151 of the detected plate 115 before every time exhaust. For example, if the gas to be discharged is acid gas, before discharging the acid gas, the actuator 104 drives the coupling 107 to rotate, which brings the inner pipe 103 and the detected plate 115 to rotate, and the sensor 113A detects the notch 1151 of the detected plate 115, which indicates the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022A of the outer pipe 102. The acid gas is discharged from the exhaust port 1022A. The

exhaust ports

1022B, 1022C are blocked by the side wall of the inner pipe 103. If the gas to be discharged is alkaline gas, before discharging the alkaline gas, the actuator 104 drives the coupling 107 to rotate, which brings the inner pipe 103 and the detected plate 115 to rotate, and the sensor 113B detects the notch 1151 of the detected plate 115, which indicates the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022B of the outer pipe 102. The alkaline gas is discharged from the exhaust port 1022B. The

exhaust ports

1022A, 1022C are blocked by the side wall of the inner pipe 103. If the gas to be discharged is combustible gas, before discharging the combustible gas, the actuator 104 drives the coupling 107 to rotate, which brings the inner pipe 103 and the detected plate 115 to rotate, and the sensor 113C detects the notch 1151 of the detected plate 115, which indicates the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022C of the outer pipe 102. The combustible gas is discharged from the exhaust port 1022C. The

exhaust ports

1022A, 1022B are blocked by the side wall of the inner pipe 103.

One advantage of the present invention is that the flow of gas which is discharged through the exhaust port 1022 of the outer pipe 102 is adjustable. Specifically, after the through-hole 1033 of the inner pipe 103 is facing the corresponding exhaust port 1022 of the outer pipe 102, it can control the actuator 104 to make the inner pipe 103 rotate a certain angle clockwise or anticlockwise so the opening size for discharging the gas can be adjusted.

In the field of semiconductor manufacturing, if using the exhaust apparatus 100 to discharge acid gas, alkaline gas or combustible gas, the gas inlet port 1013 of the gas inlet pipe 101 can connect to a process chamber where a cleaning process, an etching process and so on is carried out. When need to discharge acid gas, firstly, the actuator 104 drives the coupling 107 to rotate, which brings the inner pipe 103 and the detected plate 115 to rotate. Then detect whether the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022A of the outer pipe 102. If the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022A of the outer pipe 102, the acid gas from the process chamber enters into the inner pipe 103 through the gas inlet pipe 101 and is discharged from the through-hole 1033 of the inner pipe 103, the exhaust port 1022A of the outer pipe 102 and the exhaust pipe 1023A which connects to a facility acid gas exhaust system. When need to discharge alkaline gas, firstly, the actuator 104 drives the coupling 107 to rotate, which brings the inner pipe 103 and the detected plate 115 to rotate. Then detect whether the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022B of the outer pipe 102. If the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022B of the outer pipe 102, the alkaline gas from the process chamber enters into the inner pipe 103 through the gas inlet pipe 101 and is discharged from the through-hole 1033 of the inner pipe 103, the exhaust port 1022B of the outer pipe 102 and the exhaust pipe 1023B which connects to a facility alkaline gas exhaust system. When need to discharge combustible gas, firstly, the actuator 104 drives the coupling 107 to rotate, which brings the inner pipe 103 and the detected plate 115 to rotate. Then detect whether the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022C of the outer pipe 102. If the through-hole 1033 of the inner pipe 103 is facing the exhaust port 1022C of the outer pipe 102, the combustible gas from the process chamber enters into the inner pipe 103 through the gas inlet pipe 101 and is discharged from the through-hole 1033 of the inner pipe 103, the exhaust port 1022C of the outer pipe 102 and the exhaust pipe 1023C which connects to a facility combustible gas exhaust system. Liquid entering the gas inlet pipe 101 with the acid gas, alkaline gas or combustible gas is drained out through the drain hole 1014.

The exhaust apparatus 100 of the present invention defines a plurality of exhaust ports 1022 on the outer pipe 102 and a through-hole 1033 on the inner pipe 103, and the inner pipe 103 is driven to rotate in the pipe body 1021 of the outer pipe 102 to make the through-hole 1033 of the inner pipe 103 connect to one of the exhaust ports 1022 of the outer pipe 102 every time for discharging one kind of gas, and the other exhaust ports 1022 of the outer pipe 102 are blocked by the side wall of the inner pipe 103. Therefore, the exhaust apparatus 100 of the present invention realizes the purpose of several kinds of gases separation exhaust, and moreover, the structure of the exhaust apparatus 100 is simple with low manufacture cost and takes up small space.

Referring to FIG. 8, an outer pipe according to another embodiment of the present invention is illustrated. Similarly, the outer pipe 202 has a cylindrical pipe body 2021. A side wall of the pipe body 2021 defines three exhaust ports 2022. The centers of the three exhaust ports 2022 are on the same horizontal plane. For conveniently connecting to a facility exhaust system, every exhaust port 2022 connects to an exhaust pipe 2023. One end of every exhaust pipe 2023 connects to one exhaust port 2022 and the other end of the exhaust pipe 2023 can be connected to the facility exhaust system. Preferably, the size and shape of the three exhaust ports 2022 are uniform. The angle between two axes which respectively pass through centers of every two adjacent exhaust ports 2022 is 120 degrees. Therefore, the distance between every two adjacent exhaust ports 2022 is large, which avoids gas leaking from the adjacent exhaust ports 2022 when the gas is discharged from one exhaust port 2022.

Please refer to FIG. 9 and FIG. 10 showing an inner pipe and an outer pipe according to another embodiment of the present invention. The inner pipe 303 is cylindrical. One end of the inner pipe 303 is open and connects to the gas inlet pipe 101, and the other end of the inner pipe 303 is sealed. Specifically, the other end of the inner pipe 303 is sealed by a seal plate 3031. The center of the seal plate 3031 defines an installing groove 3032. One end of the connecting shaft 106 is fixed in the installing groove 3032 of the inner pipe 303. A side wall of the inner pipe 303 defines three through-holes 3033. The three through-holes 3033 are arranged vertically and on the same line. A seal element 3034 is set between two adjacent through-holes 3033. The seal elements 3034 are o-rings or magnetic liquid seals. The outer pipe 302 has a cylindrical pipe body 3021. A side wall of the pipe body 3021 defines three exhaust ports 3022. The three exhaust ports 3022 are on different horizontal planes and distributed staggered. Every exhaust port 3022 connects to an exhaust pipe 3023. One end of every exhaust pipe 3023 connects to one exhaust port 3022 and the other end of the exhaust pipe 3023 connects to a facility exhaust system. The inner pipe 303 is accommodated in the pipe body 3021 of the outer pipe 302. When one through-hole 3033 of the inner pipe 303 is corresponding to one exhaust port 3022 of the outer pipe 302 for discharging one kind of gas, the other exhaust ports 3022 of the outer pipe 302 are blocked by the side wall of the inner pipe 303 and the other through-holes 3033 of the inner pipe 303 are blocked by the side wall of the pipe body 3021 of the outer pipe 302.

Please refer to FIG. 11 and FIG. 12 showing an inner pipe and an outer pipe according to another embodiment of the present invention. The inner pipe 403 is cylindrical. One end of the inner pipe 403 is open and connects to the gas inlet pipe 101, and the other end of the inner pipe 403 is sealed. Specifically, the other end of the inner pipe 403 is sealed by a seal plate 4031. The center of the seal plate 4031 defines an installing groove 4032. One end of the connecting shaft 106 is fixed in the installing groove 4032 of the inner pipe 403. A side wall of the inner pipe 403 defines four through-holes 4033. The four through-holes 4033 are arranged vertically and on the same line. A seal element 4034 is set between two adjacent through-holes 4033. The seal elements 4034 are o-rings or magnetic liquid seals. The outer pipe 402 has a cylindrical pipe body 4021. A side wall of the pipe body 4021 defines four exhaust ports 4022. The four exhaust ports 4022 are on different horizontal planes and distributed staggered. Every exhaust port 4022 connects to an exhaust pipe 4023. One end of every exhaust pipe 4023 connects to one exhaust port 4022 and the other end of the exhaust pipe 4023 connects to a facility exhaust system. The inner pipe 403 is accommodated in the pipe body 4021 of the outer pipe 402. When one through-hole 4033 of the inner pipe 403 is corresponding to one exhaust port 4022 of the outer pipe 402 for discharging one kind of gas, the other exhaust ports 4022 of the outer pipe 402 are blocked by the side wall of the inner pipe 403 and the other through-holes 4033 of the inner pipe 403 are blocked by the side wall of the pipe body 4021 of the outer pipe 402.

It is recognized that the number of the exhaust ports and the through-holes is not limited. According to the kinds of gases to be discharged, the side wall of the pipe body of the outer pipe defines corresponding numbers of the exhaust ports and the side wall of the inner pipe defines corresponding numbers of the through-holes.

The foregoing description of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. Such modifications and variations that may be apparent to those skilled in the art are intended to be included within the scope of this invention as defined by the accompanying claims.

Claims

An exhaust apparatus, comprising:

an outer pipe, having a pipe body, a side wall of the pipe body defining a plurality of exhaust ports；

an inner pipe, accommodated in the pipe body of the outer pipe, one end of the inner pipe being open, and the other end of the inner pipe being sealed, a side wall of the inner pipe defining a through-hole； and

an actuator, configured to drive the inner pipe to rotate in the pipe body of the outer pipe to make the through-hole of the inner pipe face one of the exhaust ports of the outer pipe for discharging one kind of gas while other exhaust ports of the outer pipe being blocked by the side wall of the inner pipe.
The exhaust apparatus according to claim 1, wherein centers of the plurality of exhaust ports of the outer pipe are on a same horizontal plane.
The exhaust apparatus according to claim 1, wherein the through-hole of the inner pipe and the exhaust ports of the outer pipe have a same size and shape.
The exhaust apparatus according to claim 1, further comprising a gas inlet pipe, the outer pipe fixed with the gas inlet pipe and the end of the inner pipe which is open connected to the gas inlet pipe.
The exhaust apparatus according to claim 4, wherein the gas inlet pipe is substantially L-shaped and has a transverse part and a vertical part, a wall of the transverse part defines a drain hole.
The exhaust apparatus according to claim 4, further comprising a first seal ring being set between the outer pipe and the gas inlet pipe.
The exhaust apparatus according to claim 1, wherein every exhaust port of the outer pipe connects to a respective exhaust pipe.
The exhaust apparatus according to claim 1, further comprising a connecting shaft, one end of the connecting shaft fixed with the sealed end of the inner pipe, the other end of the connecting shaft fixed in a coupling, the actuator connected to the coupling, the actuator driving the inner pipe to rotate in the pipe body of the outer pipe through the coupling and the connecting shaft.
The exhaust apparatus according to claim 8, further comprising a cover plate being fixed on the outer pipe, the connecting shaft passing through the center of the cover plate, a second seal ring being set between the cover plate and the outer pipe, a third seal ring being set between the connecting shaft and the cover plate.
The exhaust apparatus according to claim 8, further comprising a plurality of sensors and a detected plate, the plurality of sensors and the detected plate being configured to detect whether the through-hole of the inner pipe is facing one of the exhaust ports of the outer pipe before exhaust, wherein the plurality of sensors are distributed around the coupling, the detected plate is set on the coupling and rotates along with the coupling, the detected plate defines a notch on an outer edge of the detected plate, the plurality of sensors are respectively corresponding to the plurality of exhaust ports of the outer pipe and an initial position, the notch of the detected plate is corresponding to the through-hole of the inner pipe, the plurality of sensors detect the notch of the detected plate.
The exhaust apparatus according to claim 10, wherein the plurality of sensors are photoelectric sensors.
The exhaust apparatus according to claim 1, wherein after the through-hole of the inner pipe is facing the corresponding exhaust port of the outer pipe, controlling the actuator to make the inner pipe rotate a certain angle clockwise or anticlockwise so the opening size for discharging the gas is adjusted.
The exhaust apparatus according to claim 1, wherein the number of the exhaust ports is three and the angle between two axes which respectively pass through centers of every two adjacent exhaust ports is 120 degrees.
An exhaust apparatus, comprising:

an outer pipe, having a pipe body, a side wall of the pipe body defining a plurality of exhaust ports；

an inner pipe, accommodated in the pipe body of the outer pipe, one end of the inner pipe being open, and the other end of the inner pipe being sealed, a side wall of the inner pipe defining a plurality of through-holes； and

an actuator, configured to drive the inner pipe to rotate in the pipe body of the outer pipe to make one through-hole of the inner pipe face one exhaust port of the outer pipe for discharging one kind of gas while other exhaust ports of the outer pipe being blocked by the side wall of the inner pipe and other through-holes of the inner pipe being blocked by the side wall of the pipe body of the outer pipe.
The exhaust apparatus according to claim 14, wherein the plurality of through-holes of the inner pipe are arranged vertically, the plurality of exhaust ports of the outer pipe are on different horizontal planes and distributed staggered.
The exhaust apparatus according to claim 14, wherein the through-holes of the inner pipe and the exhaust ports of the outer pipe have a same size and shape.
The exhaust apparatus according to claim 14, further comprising seal elements being set between two adjacent through-holes.
The exhaust apparatus according to claim 17, wherein the seal elements are o-rings or magnetic liquid seals.