WO2023234531A1

WO2023234531A1 - Oxygen generator

Info

Publication number: WO2023234531A1
Application number: PCT/KR2023/004084
Authority: WO
Inventors: 박지용
Original assignee: 한온시스템 주식회사
Priority date: 2022-05-31
Filing date: 2023-03-28
Publication date: 2023-12-07
Also published as: KR20230166457A

Abstract

The present invention relates to an oxygen generator which is capable of generating a relatively large amount of concentrated oxygen while generating little noise or vibration, the oxygen generator being characterized by comprising: a first adsorption bed including a molecular sieve; a second adsorption bed which is connected in parallel with the first adsorption bed and includes a molecular sieve; a first air pump which is connected to the supply end of one of the first adsorption bed or the second adsorption bed and supplies air; a second air pump which is connected to the discharge end of the adsorption bed connected to the first air pump among the first adsorption bed and the second adsorption bed and absorbs air; a supply valve unit which is installed at the supply ends of the first adsorption bed and the second adsorption bed and configures a flow path to determine the adsorption bed connected to the first air pump; and a discharge valve unit which is installed at the discharge ends of the first adsorption bed and the second adsorption bed and configures a flow path to determine the adsorption bed connected to the second air pump.

Description

oxygen generator

The present invention relates to an oxygen generator, and more specifically to an oxygen generator of the pressure synchronized swing adsorption type.

An oxygen generator, as its name suggests, is a device that generates oxygen. It was mainly used in medical settings to supply oxygen to patients, but has recently been applied to various fields.

Oxygen generators generate oxygen by concentrating it using various principles, and one of them uses a method of supplying compressed air to an adsorbent and removing carbon dioxide from the adsorbent to generate concentrated oxygen. Oxygen using this adsorbent is used. There are two types of generators: PSA (Pressure Swing Absorption) and RVSA (Rapid Vacuum Swing Absorption).

Figure 1 schematically shows a conventional PSA type oxygen generator and operation.

As shown in FIG. 1, the PSA type oxygen generator includes a first air pump 11, a second air pump 12, a first adsorption bed 21, a second adsorption bed 22, and a supply valve unit. (B1) and a discharge valve unit (B2).

The first air pump 11 and the second air pump 12 are connected in series and supply compressed air to the first adsorption bed 21 or the second adsorption bed 22. The air supplied from the air pump is supplied to either the first adsorption bed 21 or the second adsorption bed 22, and the air passing through the adsorption bed is supplied with oxygen due to the difference in particle size between oxygen and carbon dioxide. , carbon dioxide is adsorbed on the adsorption bed, and concentrated oxygen is ultimately produced. However, since the amount of carbon dioxide adsorbed on the adsorption bed is limited, the adsorption bed on which carbon dioxide has been adsorbed for a certain period of time needs to be regenerated. For this purpose, the discharge ends of the first adsorption bed 21 and the second adsorption bed 22 are connected. In FIG. 1A, oxygen is concentrated in the first adsorption bed 21 and regenerated in the second adsorption bed 22, and some of the oxygen discharged from the first adsorption bed 21 is transferred to the second adsorption bed 22. It is supplied to the side, and the carbon dioxide adsorbed in the second adsorption bed 22 reacts with oxygen, and the resulting air is discharged to the outside. In this process, as shown in Figure 1b, the first adsorption bed 21 and the second adsorption bed 22 change each other's roles at regular intervals, and the supply valve part B1 and the discharge valve part B2 When the role of the adsorption bed is changed, it plays a role in changing the air flow path.

Figure 2 schematically shows the oxygen generator and operation of the conventional RVSA method.

As shown in FIG. 2, the RVSA type oxygen generator, similar to the PSA type oxygen generator, includes a first air pump 11, a second air pump 12, a first adsorption bed 21, and a second air pump 12. It may include an adsorption bed 22, a first valve unit 23, and a second valve unit 24.

In the RVSA type oxygen generator, the first air pump 11 and the second air pump 12 are configured separately, and the first air pump 11 and the second air pump 12 each have a first adsorption bed 21. ) and the second adsorption bed 22, and absorbs air so that the air passes through the adsorption bed. However, since the first adsorption bed 21 and the second adsorption bed 22 also require regeneration when carbon dioxide is adsorbed above a certain level, either the first adsorption bed 21 or the second adsorption bed 22 is oxygen One is for concentration and the other is for regeneration, and the first valve unit 23 and the second valve unit 24 allow the first adsorption bed 21 and the second adsorption bed 22 to concentrate and regenerate oxygen. The air flow path is changed to achieve this, and this principle is the same as the PSA type oxygen generator described previously.

In the case of the PSA method described in Figure 1, two air pumps are connected in series to supply relatively high-pressure compressed air to the adsorption bed, so a relatively large amount of concentrated oxygen can be generated, but the problem is that noise and vibration are high. In the case of the RVSA method described in FIG. 2, one air pump is connected to one adsorption bed, so noise and vibration are lower than the PSA method, but there is a problem in that it generates a relatively small amount of concentrated oxygen.

The present invention was created to solve the problems described above. The purpose of the oxygen generator of the pressure synchronized swing adsorption method according to the present invention is to be able to generate a relatively large amount of concentrated oxygen while producing less noise and vibration. Providing an oxygen generator.

The oxygen generator of the pressure synchronized swing adsorption method according to various embodiments of the present invention to solve the problems described above includes a first adsorption bed including a molecular sieve, a second adsorption bed, the first adsorption bed, and the first adsorption bed. A first air pump connected to the supply end of one of the two adsorption beds to supply air, and a first air pump connected to the discharge end of the adsorption bed connected to the first air pump among the first and second adsorption beds to supply air. Includes a second air pump for absorption, wherein one of the first air pump and the second air pump is used for compression and the other is used for suction to simultaneously pressurize the oxygen absorption bed at the front and rear ends. It is characterized by concentrating oxygen by forming .

In addition, a supply valve unit installed at the supply end of the first adsorption bed and the second adsorption bed and forming a flow path to determine the adsorption bed connected to the first air pump, and the first adsorption bed and the second adsorption bed. It is characterized in that it further includes a discharge valve unit installed at the discharge end of the bed and forming a flow path to determine the adsorption bed connected to the second air pump.

In addition, a first common flow path at one end of which is connected to the first air pump, a 1-1 branch flow path branched from the other end of the first common flow path and connected to the first adsorption bed, and a first common flow path at the other end of the first common flow path. It includes a first-second branch flow path branched and connected to the second adsorption bed, and the supply valve unit is installed in the first-first branch flow path and the first-second branch flow path.

In addition, the supply valve part is a 1-1 valve installed in the 1-1 branch passage to open and close the 1-1 branch passage, and a 1-1 valve installed in the 1-2 branch passage to open and close the 1-2 branch passage. It includes a 1-2 valve that opens and closes, and when one of the 1-1 valve and the 1-2 valve opens a flow path, the other valve closes the flow path.

In addition, when the first air pump and the second air pump are connected to the first adsorption bed, the 1-1 valve is opened, the 1-2 valve is closed, and the first air pump and the second air pump are connected to the first adsorption bed. When the second air pump is connected to the second adsorption bed, the first valve 1-1 is closed and the first valve 1-2 is opened.

In addition, a second common flow path at one end of which is connected to the second air pump, a second-first branch flow path branched from the other end of the second common flow path and connected to the first adsorption bed, and a second common flow path at the other end of the second common flow path. It further includes a 2-2 branch flow path branched and connected to the second adsorption bed, and the discharge valve unit is installed in the 2-1 branch flow path and the 2-2 branch flow path.

In addition, the discharge valve part is a 2-1 valve installed in the 2-1 branch flow path to open and close the 2-1 branch flow path, and a 2-1 valve installed in the 2-2 branch flow path to open and close the 2-1 branch flow path. It is characterized in that it includes a 2-2 valve that opens and closes.

In addition, when the first air pump and the second air pump are connected to the first adsorption bed, the 2-1 valve is opened, the 2-2 valve is closed, and the first air pump and the second air pump are connected to the first adsorption bed. When the second air pump is connected to the second adsorption bed, the 2-1 valve is closed and the 2-2 valve is opened.

In addition, it further includes a connection passage connecting the 2nd-1st branch passage and the 2nd-2nd branch passage, and the discharge valve part is installed on the connection passage, so that oxygen flows into the first adsorption bed according to operation. It is characterized in that it includes a backflow prevention valve that allows flow only from the discharge end of the second absorption bed to the discharge end of the second absorption bed, or from the discharge end of the second absorption bed to the discharge end of the first absorption bed. .

In addition, when the first air pump and the second air pump are connected to the first adsorption bed, the backflow prevention valve allows oxygen to flow from the discharge end of the first adsorption bed to the discharge end of the second adsorption bed. When operating and the first air pump and the second air pump are connected to the second adsorption bed, the non-return valve allows oxygen to flow from the outlet end of the second adsorption bed to the outlet end of the first adsorption bed. It is characterized by operating as much as possible.

In addition, it is characterized in that it further includes a first exhaust passage connected to the first absorption bed and the outside, and a second exhaust passage connected to the second absorption bed and the outside.

In addition, at least one of the first exhaust passage and the second exhaust passage is formed on a supply end side of each of the first and second absorption beds.

In addition, an exhaust valve unit including a first exhaust valve installed in the first exhaust passage to open and close the first exhaust passage, and a second exhaust valve installed in the second exhaust passage to open and close the second exhaust passage. It is characterized by including more.

In addition, when the first air pump and the second air pump are connected to the first adsorption bed, the first exhaust valve is closed, the second exhaust valve is opened, and the first air pump and the second air When the pump is connected to the second adsorption bed, the first exhaust valve is opened and the second exhaust valve is closed.

In addition, the first adsorption bed and the second adsorption bed are connected in parallel to each other.

In the pressure synchronized swing adsorption type oxygen generator according to various embodiments of the present invention as described above, the first air pump supplies compressed air and the second air pump suctions air, so the two air pumps are identical. Because it moves air in one direction, it generates a similar amount of oxygen as a conventional PSA-type oxygen generator, but since the first and second air pumps operate independently, noise and vibration are reduced compared to a conventional PSA-type oxygen generator. It works.

Figure 1 schematically shows the oxygen generator and operation of a conventional PSA type.

Figure 2 schematically shows the oxygen generator and operation of the conventional RVSA type.

Figure 3 shows when the oxygen generator of the pressure synchronized swing adsorption method according to an embodiment of the present invention operates in the first mode;

Figure 4 shows when the oxygen generator of the pressure synchronized swing adsorption method according to an embodiment of the present invention operates in the second mode.

Hereinafter, an oxygen generator of the pressure synchronized swing adsorption method according to an embodiment of the present invention will be described in detail with reference to the attached drawings.

Figure 3 shows when the oxygen generator of the pressure synchronized swing adsorption method according to an embodiment of the present invention operates in the first mode.

Hereinafter, the synchronized swing adsorption type oxygen generator, which is the name of the present invention, is referred to as SPSA oxygen generator.

As shown in Figure 3, the SPSA oxygen generator according to an embodiment of the present invention includes a first adsorption bed 21, a second adsorption bed 22, a first air pump 11, and a second air pump ( 12), including a supply valve part (B1) and a discharge valve part (B2).

The first adsorption bed 21 and the second adsorption bed 22 are installed at a certain distance apart from each other and are connected in parallel. The first adsorption bed 21 and the second adsorption bed 22 each include a molecular sieve and a case containing the molecular sieve, which absorbs carbon dioxide contained in the air. By adsorbing, the oxygen in the passing air is concentrated and discharged. Molecular sieve is a form containing multiple pores. There is a slight difference in size between carbon dioxide particles and oxygen particles, with carbon dioxide particles being slightly larger. Molecular sieves adsorb carbon dioxide by having pores whose pores allow oxygen particles to pass through, but do not allow carbon dioxide particles to pass through. Molecular sieves can be made of various materials. Some examples of materials that can be used as molecular sieves include zeolite and activated carbon.

A supply end and a discharge end are formed in the case included in each of the first adsorption bed 21 and the second adsorption bed 22. Based on the drawing, the supply end is the upper end and the discharge end is the lower end.

The first air pump 11 compresses and supplies air. The first air pump (11) is connected to the first common passage (31), and the first common passage (31) has a first-first branch passage (41) and a first-second branch passage (42) at the extended end. branched, each of the first-first branch flow path 41 and the first-second branch flow path 42 is sequentially connected to the supply end of the first adsorption bed 21 and the supply end of the second adsorption bed 22. .

The second air pump 12 suctions air. The second air pump (12) is connected to the second common passage (32), and the second common passage (32) has a second-first branch passage (43) and a second-second branch passage (44) at the extended end. branched, each of the 2nd-1st branch flow path 43 and the 2nd-2nd branch flow path 44 is sequentially connected to the discharge end of the first adsorption bed 21 and the discharge end of the second adsorption bed 22. .

The supply valve unit (B1) is installed in the 1-1 branch passage 41 and the 1-2 branch passage 42, and as shown in FIG. 3, the supply valve unit (B1) is connected to the 1-1 valve. (B11) and the 1-2 valve (B12).

The 1-1 valve (B11) is installed in the 1-1 branch passage 41 and opens and closes the 1-1 branch passage 41, and the 1-2 valve (B12) is installed in the 1-2 branch passage (41). It is installed in 42) to open and close the first and second branch passages (42).

The discharge valve unit (B2) is installed in the 2-1 branch passage 43 and the 2-2 branch passage 44, and as shown in FIG. 3, the 2-1 valve (B21) and the 2- Includes 2 valves (B22).

The 2-1 valve (B21) is installed in the 2-1 branch flow path (43) to open and close the 2-1 branch flow path (43), and the 2-2 valve (B22) is installed in the 2-1 branch flow path (43). 44) to open and close the 2nd-2nd branch passageway (44).

As shown in FIG. 3, the SPSA oxygen generator according to an embodiment of the present invention may further include a connection passage 47, and the discharge valve unit B2 is a counterflow valve installed on the connection passage 47. It may further include a prevention valve (B23).

The connection passage (47) connects the 2nd-1st branch passageway (43) and the 2nd-2nd branch passageway (44), and the backflow prevention valve (B23) is installed on the connection passage (47) so that oxygen flows in accordance with its operation. Let it flow only from the discharge end of the first absorption bed (21) to the discharge end of the second absorption bed (22), or only from the discharge end of the second absorption bed (22) to the discharge end of the first absorption bed (21). Let it flow in.

As shown in FIG. 3, the SPSA oxygen generator according to an embodiment of the present invention further includes a first exhaust passage 45, a second exhaust passage 46, and an exhaust valve unit B3.

The first exhaust flow path 45 is a flow path configured to connect the first absorption bed 21 to the outside, and the second exhaust flow path 46 is a flow path configured to connect the second absorption bed 22 to the outside. Each of the first exhaust passage 45 and the second exhaust passage 46 is formed on the supply end side of the first absorption bed 21 and the second absorption bed 22, respectively. This is to extend the movement path of the gas passing through the inside of the adsorption bed when regeneration is performed in each of the two adsorption beds (22). However, the present invention is not limited to forming the first exhaust passage 45 and the second exhaust passage 46 on the supply side of the adsorption bed, and the first exhaust passage 45 and the second exhaust passage 46 are provided at various positions of the adsorption bed. A second exhaust passage 46 may be formed.

As shown in FIG. 3, the exhaust valve unit B3 includes a first exhaust valve B31 and a second exhaust valve B32.

The first exhaust valve (B31) is installed in the first exhaust passage 45 and opens and closes the first exhaust passage 45, and the second exhaust valve (B32) is installed in the second exhaust passage 46 to discharge the second exhaust. Open and close the euro (46).

In the SPSA oxygen generator according to the present invention, the first air pump 11 and the second air pump 12 are connected to one of the first adsorption bed 21 and the second adsorption bed 22, and the connected adsorption bed Oxygen concentration takes place in the , and regeneration takes place in the unconnected adsorption bed. At this time, the adsorption bed connected to the first air pump 11 and the second air pump 12 can be changed, and the first air pump 11 and the second air pump 12 are connected to the first adsorption bed 21. ) is referred to as the first mode, and the case where the first air pump 11 and the second air pump 12 are connected to the second adsorption bed 22 is referred to as the second mode. The duration and conversion cycle of the first mode and the second mode may vary depending on the specifications of the SPSA oxygen generator according to the present invention, but may generally be several seconds apart. In order to change the operation mode between the first mode and the second mode, the supply valve unit (B1), discharge valve unit (B2), and exhaust valve unit (B3) must operate periodically, which will be described in detail.

As shown in FIG. 3, when the SPSA oxygen generator according to an embodiment of the present invention operates in the first mode, the 1-1 valve (B11) opens and the 1-2 valve (B12) closes. , the 2-1 valve (B21) is open, the 2-2 valve (B22) is closed, and the non-return valve (B23) supplies oxygen from the discharge end of the first absorption bed to the discharge end of the second absorption bed. operates to allow inflow, the first exhaust valve (B31) is closed, and the second exhaust valve (B32) is opened. When the valves operate in this way, air is supplied to the supply end of the first adsorption bed 21 through the pressure generated from each of the first air pump 11 and the second air pump 12, and the first adsorption bed (21) Oxygen is concentrated as it passes through 21). Some of the oxygen discharged through the discharge end of the first adsorption bed 21 moves toward the connection passage 47 and flows into the second adsorption bed 22. Carbon dioxide is adsorbed on the molecular sieve included in the second adsorption bed 22, and the oxygen supplied to the second adsorption bed 22 is exhausted along with the adsorbed carbon dioxide to the second exhaust passage 46. , Accordingly, the second absorption bed 22 is regenerated.

As shown in Figure 4, when the SPSA oxygen generator of the present invention operates in the second mode, the 1-1 valve (B11) is closed, the 1-2 valve (B12) is open, and the 2-1 valve (B12) is open. The valve (B21) is closed, the 2-2 valve (B22) is open, and the backflow prevention valve (B23) allows oxygen to flow from the discharge end of the second adsorption bed (22) to the discharge end of the first adsorption bed (21). It operates to allow inflow, the first exhaust valve (B31) opens, and the second exhaust valve (B32) operates to close. When the valves operate in this way, air is supplied to the supply end of the second adsorption bed 22 through the pressure generated from each of the first air pump 11 and the second air pump 12, and the second adsorption bed (22) Oxygen is concentrated as it passes through 22). Some of the oxygen discharged through the discharge end of the second adsorption bed 22 moves toward the connection passage 47 and flows into the first adsorption bed 21. Carbon dioxide is adsorbed on the molecular sieve included in the first adsorption bed 21, and the oxygen supplied to the first adsorption bed 21 is exhausted along with the adsorbed carbon dioxide to the first exhaust passage 45. , Accordingly, the first absorption bed 21 is regenerated.

Control of the valve in the first and second modes as described above can be performed by a separate control unit, and the control unit includes the 1-1 valve (B11), the 1-2 valve (B12), and the 2-1 valve. A communication line for transmitting control signals to each of (B21), 2-2 valve (B22), non-return valve (B23), 1st exhaust valve (B31), and 2nd exhaust valve (B32) is wired or wireless. It can be configured.

The SPSA oxygen generator according to an embodiment of the present invention operates in the first mode and the second mode as described above, compressing air in the first air pump 11 and the second air pump 12, respectively. By injecting and suctioning, compressed air can be moved to the adsorption bed at a pressure similar to that of the conventional PSA method, and the amount of concentrated oxygen generated can be similar to that of the PSA type oxygen generator. In addition, since the first air pump 11 and the second air pump 12 are used separately, the first air pump 11 compresses and pushes air, and the second air pump 12 sucks and pulls air, The mechanical noise and vibration generated as the piston rubs against the cylinder wall when the vacuum pump is driven is lower than that of the PSA-type oxygen generator, which supplies compressed air by pushing it from only one side, and can be implemented to a similar level as the RVSA-type oxygen generator. there is.

The present invention is not limited to the above-described embodiments, and the scope of application is diverse. Of course, various modifications and implementations are possible without departing from the gist of the present invention as claimed in the claims.

[Explanation of symbols]

11: first air pump 12: second air pump

21: first adsorption bed 22: second adsorption bed

23: first valve part 24: second valve part

31: 1st common passage 32: 2nd common passage

41: 1st-1st quarter euro 42: 1st-2nd quarter euro

43: 2nd-1st quarter Euro 44: 2nd-2nd quarter Euro

45: 1st exhaust flow path 46: 2nd exhaust flow path

47: Connection passage B1: Supply valve part

B11: Valve 1-1 B12: Valve 1-2

B2: Discharge valve part B21: 2-1 valve

B22: 2-2 valve B23: Non-return valve

B3: Exhaust valve unit B31: First exhaust valve

B32: 2nd exhaust valve

Claims

A first adsorption bed containing molecular sieve; Second adsorption bed;

a first air pump connected to a supply end of either the first adsorption bed or the second adsorption bed to supply air; and

a second air pump connected to the discharge end of the first adsorption bed and the second adsorption bed connected to the first air pump to absorb air;

Including,

One of the first air pump and the second air pump is used for compression and the other is used for suction to concentrate oxygen by simultaneously forming pressurization at the front and rear ends of the oxygen adsorption bed. oxygen generator.
According to paragraph 1,

a supply valve unit installed at the supply end of the first adsorption bed and the second adsorption bed and forming a flow path to determine the adsorption bed connected to the first air pump; and

a discharge valve unit installed at discharge ends of the first and second adsorption beds and forming a flow path to determine the adsorption bed connected to the second air pump;

An oxygen generator further comprising:
According to paragraph 2,

The supply valve unit and the discharge valve unit operate periodically to change the suction bed connected to the first air pump and the second air pump, and select the first air pump and the second suction bed among the first suction bed and the second suction bed. An oxygen generator characterized in that oxygen is concentrated in the adsorption bed connected to the second air pump and regeneration is performed in the adsorption bed not connected.
According to paragraph 2,

a first common flow passage whose end is connected to the first air pump;

a first-first branch flow path branched from the other end of the first common flow path and connected to the first adsorption bed; and

a first-second branch flow path branched from the other end of the first common flow path and connected to the second adsorption bed;

Includes,

The oxygen generator, characterized in that the supply valve unit is installed in the first-first branch flow path and the first-second branch flow path.
According to paragraph 4,

The supply valve part,

A 1-1 valve installed in the 1-1 branch flow path to open and close the 1-1 branch flow path; and

A 1-2 valve installed in the first-2 branch flow path to open and close the first-2 branch flow path;

Includes,

An oxygen generator, characterized in that when one of the 1-1 valve and the 1-2 valve opens a flow path, the other valve closes the flow path.
According to clause 5,

When the first air pump and the second air pump are connected to the first adsorption bed, the 1-1 valve opens and the 1-2 valve closes,

When the first air pump and the second air pump are connected to the second adsorption bed, the 1-1 valve is closed and the 1-2 valve is open.
According to paragraph 1,

a second common flow path whose end is connected to the second air pump;

a second-first branch flow path branched from the other end of the second common flow path and connected to the first adsorption bed; and

a second-second branch flow path branched from the other end of the second common flow path and connected to the second adsorption bed;

It further includes,

The oxygen generator, characterized in that the discharge valve unit is installed in the 2nd-1st branch flow path and the 2nd-2nd branch flow path.
In clause 7,

The discharge valve part,

A 2-1 valve installed in the 2-1 branch flow path to open and close the 2-1 branch flow path; and

A 2-2 valve installed in the 2-2 branch flow path to open and close the 2-2 branch flow path;

An oxygen generator comprising:
According to clause 8,

When the first air pump and the second air pump are connected to the first adsorption bed, the 2-1 valve opens and the 2-2 valve closes,

When the first air pump and the second air pump are connected to the second adsorption bed, the 2-1 valve is closed and the 2-2 valve is open.
According to clause 8,

A connecting passage connecting the 2nd-1st branch passageway and the 2nd-2nd branch passageway;

It further includes,

The discharge valve part,

It is installed on the connection passage, so that oxygen flows only from the discharge end of the first absorption bed to the discharge end of the second absorption bed, depending on the operation, or from the discharge end of the second absorption bed to the first absorption bed. A non-return valve that allows inflow only to the discharge end of the device;

An oxygen generator comprising:
According to clause 10,

When the first air pump and the second air pump are connected to the first adsorption bed, the non-return valve operates to allow oxygen to flow from the outlet end of the first adsorption bed to the outlet end of the second adsorption bed. ,

When the first air pump and the second air pump are connected to the second adsorption bed, the non-return valve operates to allow oxygen to flow from the outlet end of the second adsorption bed to the outlet end of the first adsorption bed. An oxygen generator characterized in that.
According to paragraph 1,

A first exhaust passage connected to the first adsorption bed and the outside; and

a second exhaust passage connected to the second adsorption bed and the outside;

An oxygen generator further comprising:
According to clause 12,

At least one of the first exhaust passage and the second exhaust passage,

An oxygen generator, characterized in that it is formed on the supply end side of each of the first adsorption bed and the second adsorption bed.
According to clause 12,

an exhaust valve unit including a first exhaust valve installed in the first exhaust passage to open and close the first exhaust passage, and a second exhaust valve installed in the second exhaust passage to open and close the second exhaust passage;

An oxygen generator further comprising:
According to clause 14,

When the first air pump and the second air pump are connected to the first adsorption bed, the first exhaust valve is closed and the second exhaust valve is open,

When the first air pump and the second air pump are connected to the second adsorption bed, the first exhaust valve opens and the second exhaust valve closes.
According to paragraph 1,

The oxygen generator is characterized in that the first adsorption bed and the second adsorption bed are connected in parallel to each other.