A pressure regulating system for micro air flow control

Abstract

The application relates to a pressure regulating system for micro air flow control, belongs to the gas conveying field, and comprises a pilot pressure reducing valve, a main valve, an air flow control device and a pipeline assembly. The pipeline assembly comprises a main inlet pipe, a main outlet pipe, a pilot branch pipe, a main valve control pipe and a bypass pipe. The main inlet pipe is connected with the inlet of the main valve, the main outlet pipe is connected with the outlet of the main valve, one end of the pilot branch pipe is connected with the main inlet pipe and the other end is connected with the main valve control pipe, the end of the main valve control pipe, which is far away from the pilot branch pipe, is connected with the control port of the main valve, one end of the bypass pipe is connected with the pilot branch pipe and the other end is connected with the main outlet pipe, the air flow control device is arranged on the bypass pipe, the pilot pressure reducing valve is arranged on the pilot branch pipe, and the air flow control device is used for controlling the size of the bidirectional air flow of the bypass pipe. The application not only solves the problem that the service life of the pilot pressure reducing valve is short due to reverse air flow, but also can be applied to a use environment with large flow.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of gas delivery, in particular to a pressure regulating system for micro gas flow control. BACKGROUND

[0002] In the semiconductor processing industry, the gas path system for delivering toxic and harmful gas usually needs to be provided with a pressure reducing structure to regulate the gas pressure of the gas path, so as to prevent the problems of gas leakage or damage of the valve due to high pressure.

[0003] Figure 1 The pressure regulating structure of the existing gas path system. When the pilot pressure reducing valve 1 is closed, the main valve 2 is closed, and the gas from the main inlet pipe 3 cannot enter the main valve 2, and the main outlet pipe 4 does not output gas. When the pilot pressure reducing valve 1 is opened, the gas enters the pilot branch pipe 5, and then enters the main valve 2 through the main valve control pipe 6, pushing the piston 25 of the main valve 2 to move downward (the diaphragm 24 moves downward to push the piston 25 to move downward), and then pushing the valve rod 26 to move downward to open the valve port 28 of the main valve 2, and the gas from the main inlet pipe 3 enters the valve body 2 and flows to the main outlet pipe 4. By controlling the set pressure of the pilot pressure reducing valve 2, the pressure balance at the front and rear ends of the piston 25 is achieved, so as to control the pressure of the main pipe. When it is necessary to reduce the gas pressure of the main pipe, it is necessary to close the valve port 28 of the main valve 2, at which time the piston 25 needs to move upward, and the piston 25 needs to discharge the gas in the piston cavity 22. The gas can only flow back to the pilot pressure reducing valve 1 through the main valve control pipe 6. This way not only slows down the backflow speed, but also causes the pressure regulating effect to be slow, and the reverse gas flow also affects the service life of the pilot pressure reducing valve. SUMMARY

[0004] In order to solve the problem of low service life of the pilot pressure reducing valve caused by reverse gas flow, the present application provides a pressure regulating system for micro gas flow control.

[0005] The pressure regulating system for micro gas flow control provided by the present application adopts the following technical scheme:

[0006] A pressure regulating system for micro gas flow control, comprising a pilot pressure reducing valve, a main valve, a gas flow control device and a pipe assembly, the pipe assembly comprising a main inlet pipe, a main outlet pipe, a pilot branch pipe, a main valve control pipe and a bypass pipe, the main inlet pipe being connected with the inlet of the main valve, the main outlet pipe being connected with the outlet of the main valve, one end of the pilot branch pipe being connected with the main inlet pipe and the other end being connected with the main valve control pipe, the end of the main valve control pipe away from the pilot branch pipe being connected with the control port of the main valve, one end of the bypass pipe being connected with the pilot branch pipe and the other end being connected with the main outlet pipe, the gas flow control device being arranged on the bypass pipe, the pilot pressure reducing valve being arranged on the pilot branch pipe, and the gas flow control device being used to control the size of the bidirectional gas flow of the bypass pipe.

[0007] By adopting the technical scheme, the bypass pipe is arranged at the front end of the rear-end main valve control pipe of the pilot pressure reducing valve, and the gas flow in the main valve is discharged to the main outlet pipe, so that the backflow speed is fast, the pressure regulating effect is improved, and the pilot pressure reducing valve is not affected by the reverse gas flow, thereby prolonging the service life of the pilot pressure reducing valve. The gas flow control device is arranged on the bypass pipe, so that the large gas flow on the pilot branch pipe and the main valve control pipe cannot enter the main outlet pipe through the bypass pipe, thereby avoiding the problem of insufficient pressure at the front end of the control port of the main valve, preventing the main valve from being closed, preventing the large gas flow in the main outlet pipe from entering the pilot branch pipe and the main valve control pipe through the bypass pipe, preventing the large gas flow from impacting the pilot pressure reducing valve in the reverse direction, preventing the damage of the pilot pressure reducing valve, and preventing the large gas flow from entering the front end of the control port of the main valve, so that the main valve is forced to open.

[0008] As a further improvement of the above technical scheme, the gas flow control device comprises a gas flow valve body and a bidirectional valve disc, the gas flow valve body is provided with a gas flow channel and a mounting channel, the two ends of the gas flow channel are connected with the bypass pipe, the mounting channel divides the gas flow channel into two sections, the bidirectional valve disc is located in the mounting channel, and the two ends of the bidirectional valve disc are connected with the gas flow valve body through elastic members to suspend the bidirectional valve disc between the two sections of the gas flow channel.

[0009] By adopting the above technical scheme, the bidirectional valve disc can move between the two sections of the gas flow channel under the suspension of the elastic members. When the gas flow at the rear end of the pressure reducing valve is drawn into the bypass pipe, the bidirectional valve disc is pushed to move to the side close to the main outlet pipe, so that the large gas flow on the pilot branch pipe and the main valve control pipe is blocked and drawn away by the main outlet pipe. When the gas flow in the main outlet pipe flows to the bypass pipe, the bidirectional valve disc moves to the side close to the pilot pressure reducing valve, so that the large gas flow is blocked from flowing into the pilot pressure reducing valve and the main valve control pipe in the reverse direction, thereby reducing the impact on the pilot pressure reducing valve and preventing the main valve from being suddenly opened and unstable.

[0010] As a further improvement of the above technical scheme, the elastic member comprises a spring one and a spring two, and the two ends of the mounting channel are respectively provided with spring cavities. The ends of the spring one and the spring two away from each other are respectively connected with the inner walls of the spring cavities, and the ends of the spring one and the spring two close to each other are respectively connected with the bidirectional valve disc.

[0011] By adopting the above technical scheme, the elastic member is provided with two independent springs one and two, which are convenient for connection with the bidirectional valve disc.

[0012] As a further improvement of the above technical scheme, the surfaces of the bidirectional valve disc facing the two sections of the gas flow channel are respectively provided with guide rods, the guide rods extend into the corresponding gas flow channels, and the outer wall of the guide rod and the inner wall of the gas flow channel have a gap.

[0013] By adopting the above technical scheme, the guide rod functions to guide the movement of the bidirectional valve disc, so as to prevent the bidirectional valve disc from deviating during movement.

[0014] As a further improvement of the above technical solution, the pilot branch pipe, the main valve control pipe and the bypass pipe are connected through a tee joint.

[0015] By adopting the above technical solution, the tee joint realizes detachable connection between the pilot branch pipe, the main valve control pipe and the bypass pipe, facilitating disassembly, replacement, maintenance and cleaning.

[0016] As a further improvement of the above technical solution, the main valve is internally provided with a control cavity, a piston cavity and a valve core cavity, the main valve control pipe is communicated with the control cavity through a control port, a diaphragm is arranged between the control cavity and the piston cavity, a piston is arranged in the piston cavity, a valve rod and a valve core are arranged in the valve core cavity, the piston is connected with the valve rod, the valve rod is connected with the valve core, a valve port is arranged between the inlet and the outlet of the main valve, the valve port is located in the valve core cavity, and the valve core is used to open and close the valve port to control the on-off of the inlet and the outlet of the main valve. A flow baffle is arranged in the control cavity, the diaphragm is located between the flow baffle and the piston, the flow baffle is provided with a through flow guide channel, and the flow guide channel faces the diaphragm.

[0017] As a further improvement of the above technical solution, the piston cavity is connected with the outlet of the main valve through an exhaust channel.

[0018] By adopting the above technical solution, when the main valve is opened, the movement of the piston can exhaust the gas in the piston cavity from the piston cavity, thereby facilitating the movement of the piston to make the valve core of the main valve more easily open the valve port.

[0019] In summary, the present application has at least one of the following beneficial technical effects:

[0020] 1. By arranging the bypass pipe, the gas flow in the piston cavity of the main valve is discharged to the main outlet pipe, which does not affect the pilot pressure reducing valve due to backflow, thereby prolonging the service life of the pilot pressure reducing valve; the gas flow control device is arranged on the bypass pipe, the gas flow of the bypass pipe is adjusted in two directions, when used under the condition of large flow, the large gas flow passing through the bypass pipe and being sucked away by the main outlet pipe can be prevented, which causes the main valve to be unable to open, and the large gas flow of the main outlet pipe flowing back to the pilot branch pipe through the bypass pipe to cause a certain impact on the pilot pressure reducing valve can also be prevented, thereby meeting the use condition of large flow. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a structural schematic diagram of a pressure regulating system in the prior art.

[0022] Figure 2 is a structural schematic diagram of a pressure regulating system with micro gas flow control in the embodiment of the present application.

[0023] Figure 3 is a structural schematic diagram of a main valve in the embodiment of the present application.

[0024] Figure 4 is a schematic diagram of a bidirectional valve disc moving downward in the embodiment of the present application.

[0025] Figure 5 is a schematic diagram of a bidirectional valve disc moving upward in the embodiment of the present application.

[0026] Reference signs: 1, pilot pressure reducing valve; 2, main valve; 20, flow blocking plate; 201, flow guiding channel; 21, control cavity; 22, piston cavity; 23, valve core cavity; 24, diaphragm; 25, piston; 26, valve rod; 27, valve core; 28, valve port; 29, exhaust channel; 3, main inlet pipe; 4, main outlet pipe; 5, pilot branch pipe; 6, main valve control pipe; 7, bypass pipe; 8, gas flow control device; 81, gas flow valve body; 82, bidirectional valve disc; 83, gas flow channel; 84, mounting channel; 85, spring one; 86, spring two; 87, spring cavity; 88, guide rod; 9, three-way joint. DETAILED DESCRIPTION

[0027] The following will be described in detail with reference to the accompanying drawings. Figures 2-5 The present application will be further described in detail.

[0028] The "up", "down", "left", "right", "front", "back" and other directional words in the present application only represent the relative positions in the drawings, are for the convenience of describing the present application, and do not represent the absolute positions of the products, and should not be regarded as a limitation on the present application.

[0029] The embodiment of the present application discloses a micro gas flow control pressure regulating system. Referring to Figure 2 , the micro gas flow control pressure regulating system comprises a pilot pressure reducing valve 1, a main valve 2, a gas flow control device 8 and a pipeline assembly, the pipeline assembly comprises a main inlet pipe 3, a main outlet pipe 4, a pilot branch pipe 5, a main valve control pipe 6 and a bypass pipe 7, the main inlet pipe 3 is connected with an inlet of the main valve 2, and the main outlet pipe 4 is connected with an outlet of the main valve 2. One end of each of the pilot branch pipe 5, the main valve control pipe 6 and the bypass pipe 7 is connected through a three-way joint 9, one end of the pilot branch pipe 5 away from the three-way joint 9 is connected in parallel with the main inlet pipe 3, one end of the main valve control pipe 6 away from the three-way joint 9 is connected with a control port of the main valve 2, and one end of the bypass pipe 7 away from the three-way joint 9 is connected with the pilot branch pipe 5. The pilot pressure reducing valve 1 is arranged on the pilot branch pipe 5. After gas enters the main inlet pipe 3, part of the gas enters the pilot branch pipe 5, passes through the pilot pressure reducing valve 1, then passes through the main valve control pipe 6 to reach the control port of the main valve 2 to open the main valve 2, so that the other part of the gas in the main inlet pipe 3 enters the main valve 2 and flows out of the main outlet pipe 4.

[0030] The main inlet pipe 3 and the main outlet pipe 4 constitute a main pipe line, which is connected with an external gas delivery pipe line to deliver gas, and the balance between the pressure at the rear end of the pilot pressure reducing valve 1 and the outlet pressure of the main outlet pipe 4 realizes the closing of the main valve 2, the pressure regulation to the set value, and thus the pressure regulation of the external gas delivery pipe line. By the arrangement of the bypass pipe 7, when the gas pressure on the main pipe line decreases, the gas flow in the main valve control pipe 6 is discharged to the main outlet pipe 4, compared with the prior art in which the gas in the main valve 2 can only return to the pilot pressure reducing valve 1 through the main valve control pipe 6, the arrangement of the bypass pipe 7 not only has a fast return speed and improves the pressure regulating effect, but also does not affect the pilot pressure reducing valve 1 by the reverse gas flow, and thus improves the service life of the pilot pressure reducing valve 1.

[0031] The gas flow control device 8 is arranged on the bypass pipe 7, and is used to control the size of the bidirectional gas flow of the bypass pipe 7, and can control the bypass pipe 7 to pass a small flow. In this way, the gas flow control device 8 can prevent the large gas flow on the pilot branch pipe 5 and the main valve control pipe 6 from entering the main outlet pipe 4 through the bypass pipe 7, so as to avoid the problem of insufficient pressure at the front end of the control port of the main valve 2 to cause the closing of the main valve 2, and can also prevent the large gas flow in the main outlet pipe 4 from entering the pilot branch pipe 5 and the main valve control pipe 6 through the bypass pipe 7, so as to avoid the damage of the pilot pressure reducing valve 1 caused by the reverse impact of the large gas flow, and avoid the large gas flow entering the front end of the control port of the main valve 2 to force the opening of the main valve 2.

[0032] Referring to Figure 2 In the embodiment, the gas flow control device 8 comprises a gas flow valve body 81 and a bidirectional valve flap 82, the gas flow valve body 81 is provided with a gas flow passage 83 and a mounting passage 84, both ends of the gas flow passage 83 are connected with the bypass pipe 7, that is, the bypass pipe 7 is divided into two sections, and the two sections of the bypass pipe 7 are connected through the gas flow passage 83. The mounting passage 84 divides the gas flow passage 83 into two sections, the bidirectional valve flap 82 is arranged in the mounting passage 84, both ends of the bidirectional valve flap 82 are connected with the gas flow valve body 81 through elastic members, and the elastic members make the bidirectional valve flap 82 suspended between the two sections of the gas flow passage 83. Specifically, both ends of the mounting passage 84 are provided with spring cavities 87, the mounting passage 84 and the spring cavities 87 at both ends form an H-shaped structure, one elastic member is arranged in each spring cavity 87, the elastic member is composed of a spring one 85 and a spring two 86, the spring one 85 and the spring two 86 are arranged in a line in the spring cavity 87, one end of the spring one 85 and the spring two 86 away from each other is connected with the inner wall of the spring cavity 87, and one end of the spring one 85 and the spring two 86 close to each other is connected with the bidirectional valve flap 82, and the bidirectional valve flap 82 is suspended between the spring one 85 and the spring two 86. Figure 4 When the gas flow on the side of the spring one 85 is large, the bidirectional valve flap 82 is pushed to move downward, blocks the pipe opening of the lower section of the gas flow passage 83, prevents the large gas flow from entering the main outlet pipe 4, and allows the small gas flow to enter the main outlet pipe 4. Figure 5When the air flow on the side of spring 86 is large, the push pushes the two-way valve flap 82 to move upward, blocks the pipe orifice of the upper section air flow passage 83, prevents large air flow from entering the pilot branch pipe 5 and the main valve control pipe 6, and allows small air flow to enter the pilot branch pipe 5 and the main valve control pipe 6.

[0033] In the embodiment, the upward face and the downward face of the two-way valve flap 82 are respectively provided with guide rods 88, the upper guide rod 88 extends into the upper section air flow passage 83, and the lower guide rod 88 extends into the lower section air flow passage 83b, and a gap is formed between the outer wall of the guide rod 88 and the inner wall of each air flow passage 83 to facilitate air flow into the air flow passage 83. The guide rod 88 functions to guide the movement of the two-way valve flap 82 and prevent the two-way valve flap 82 from deviating during upward movement or downward movement.

[0034] Referring to Figure 3 In the embodiment, the main valve 2 is provided with a control cavity 21, a piston cavity 22 and a valve core cavity 23, the main valve control pipe 6 is communicated with the control cavity 21 through a control port, a diaphragm 24 is arranged between the control cavity 21 and the piston cavity 22, a piston 25 is arranged in the piston cavity 22, a valve rod 26 and a valve core 27 are arranged in the valve core cavity 23, the piston 25 is connected with the valve rod 26, the valve rod 26 is connected with the valve core 27, a valve port 28 is arranged between the inlet and the outlet of the main valve 2, and the valve port 28 is located in the valve core cavity 23. A flow baffle 20 is arranged in the control cavity 21, the diaphragm 24 is located between the flow baffle 20 and the piston 25, a flow guide passage 201 is arranged through the flow baffle 20, the number of the flow guide passages 201 is two, and the flow guide passages 201 are directed to the diaphragm 24 to push the diaphragm 24. The piston cavity 22 is connected with the outlet of the main valve 2 through an exhaust passage 29. When the main valve 2 needs to be opened, air flow enters the control cavity 21 from the main valve control pipe 6 and the control port, pushes the diaphragm 24 to bend downward through the flow guide passage 201, and then pushes the piston 25 to move downward, the piston 25 drives the valve rod 26 and the valve core 27 to move downward, the valve port 28 is gradually opened, the main valve 2 is opened, the main inlet pipe 3 and the main outlet pipe 4 are communicated, and air flow on the main pipeline is realized; when the main valve 2 needs to be closed, air flow on the main pipeline reversely flows into the piston cavity 22 from the exhaust passage 29 to push the piston 25 to move upward (at this time, the air pressure at the valve port 28 is greater than that of the air flow entering the control port), the valve rod 26 and the valve core 27 move upward, the valve port 28 is gradually closed, and the main valve 2 is closed.

[0035] The implementation principle of the pressure regulating system for small air flow control in the embodiment is as follows:

[0036] Referring to Figure 2, assume that the gas pressure of the external gas delivery pipeline needs to be adjusted to N, that is, the output pressure of the pressure regulating system is N. In use, the pressure of the pilot pressure reducing valve 1 is adjusted to N, and the gas flow on the external gas delivery pipeline enters the main inlet pipe 3. Since the main valve 2 is not opened at this time, the gas flow cannot pass through the main valve 2, so the gas flow enters the pilot branch pipe 5, enters the pilot pressure reducing valve 1, and then enters the main valve control pipe 6 to enter the control port of the main valve 2, pushes the piston 25 to move downward, and opens the valve port 28. At this time, the main valve 2 is gradually opened, the main pipeline is connected, and the gas flow slowly enters the main valve 2 and then flows into the main outlet pipe 4. At this time, the pressure at the main outlet pipe 4 is much smaller than the pressure N at the front end of the control port of the main valve 2 (the pressure at the front end of the control port is the output pressure N at the rear end of the pilot pressure reducing valve 1). The main valve 2 is always in an open state, and the gas flow on the main pipeline is continuously output. When the pressure at the main outlet pipe 4 slowly increases to N, the gas flow reverses from the exhaust passage 29 into the piston cavity 22, pushes the piston 25 to move upward, drives the valve core 27 to move upward, and the valve port 28 is gradually closed until the main valve 2 is closed. At this time, the pressure control of the pressure regulating system is N, which meets the pressure control requirement of the external wall gas delivery pipeline. At this time, the main pipeline stops delivering gas, and when the pressure is lower than N again, the main valve 2 is re-opened to deliver gas again. When the piston 25 moves upward, the gas in the piston cavity 22 of the main valve 2 flows into the main outlet pipe 4 through the main valve control pipe 6 and the bypass pipe 7, and does not flow back to the pilot pressure reducing valve 1. Since the gas pressure at the main outlet pipe 4 and the pressure at the rear end of the pilot pressure reducing valve 1 are both N, the two-way valve flap 82 of the gas flow control device 8 is in the middle position of the two gas flow passages 83 at this time.

[0037] When large flow delivery is performed, the gas flow on the main pipeline increases, and the large gas flow on the main outlet pipe 4 forms a Venturi effect, which draws away the gas flow at the rear end of the pilot pressure reducing valve 1 through the bypass pipe 7, causing the pressure at the rear end of the pilot pressure reducing valve 1 to decrease, the pressure of the main valve control pipe 6 to decrease, and the large gas flow on the main pipeline at the rear end of the control port of the main valve 2 to push the piston 25 to move upward, causing the valve port 28 of the main valve 2 to decrease or even forcing the main valve 2 to be closed, resulting in a decrease in the gas flow on the main pipeline and an inability to perform large flow delivery. To solve this problem, the gas flow control device 8 is arranged. The suction on the main outlet pipe 4 causes a large amount of gas flow at the rear end of the pilot pressure reducing valve 1 to flow into the upper gas flow passage 83, thereby pushing the two-way valve flap 82 to move downward, as shown in Figure 4 , close to the lower gas flow passage 83, and block the large gas flow from entering the main outlet pipe 4, thereby preventing the gas flow at the rear end of the pilot pressure reducing valve 1 and the front end of the main valve control pipe 6 from being drawn away in a large amount. At this time, the gas pressure of the main valve control pipe 6 is in a high pressure state, thereby pushing the piston 25 to move downward, the valve port 28 is in a fully open state, the large gas flow on the main pipeline passes through, and the requirement of large flow delivery is met. The two-way valve flap 82 allows a small amount of gas flow to pass through the lower gas flow passage 83, so as to keep the pressure at the rear end of the pilot pressure reducing valve 1 stable.

[0038] When the large flow is delivered, the downstream end of the main outlet pipe 4 is suddenly closed, the main pipeline is cut off, and the main valve 2 cannot be closed at this time. Due to the "water hammer effect", the airflow at the outlet end of the main outlet pipe 4 reverses and flows back into the main valve 2, pushing the piston 25 to move upwards and the valve core 27 to move upwards, closing the valve port 28, and the main valve 2 is closed. Another part enters the bypass pipe 7. The pressure of the reverse airflow is much greater than the pressure N at the rear end of the pilot pressure reducing valve, and the reverse airflow will enter the pilot branch pipe 5 and impact the pilot pressure reducing valve 1, causing damage to the pilot pressure reducing valve 1. The reverse airflow will also enter the main valve control pipeline 6, and the piston 25 will move downwards instantaneously, causing the main valve 2 to suddenly open, causing the main valve 2 to be unstable, and also causing damage to the main valve 2. To solve this problem, the airflow control device 8 is arranged. The reverse airflow enters the bypass pipe 7 and pushes the two-way valve flap 82 upwards, as shown in Figure 5 , close to the upper airflow passage 83, to prevent large airflow from entering the pilot branch pipe 5 and the main valve control pipeline 6. On the one hand, the impact of large airflow on the pilot pressure reducing valve 1 is avoided, and on the other hand, the airflow in the main valve control pipeline 6 will not suddenly increase, so that the main valve 2 will not be opened instantaneously, reducing the damage to the main valve 2. The two-way valve flap 82 allows a small amount of airflow to pass through the upper airflow passage 83, so as to keep the pressure on both sides of the piston 25 of the main valve 2 stable.

[0039] The above are preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, any equivalent changes made on the basis of the structure, shape, and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A pressure regulation system for micro-airflow control, characterized in that: The system includes a pilot pressure reducing valve (1), a main valve (2), an airflow control device (8), and a piping assembly. The piping assembly includes a main inlet pipe (3), a main outlet pipe (4), a pilot branch pipe (5), a main valve control pipe (6), and a bypass pipe (7). The main inlet pipe (3) is connected to the inlet of the main valve (2), and the main outlet pipe (4) is connected to the outlet of the main valve (2). One end of the pilot branch pipe (5) is connected to the main inlet pipe (3), and the other end is connected to the main valve control pipe (6). The end of the main valve control pipe (6) away from the pilot branch pipe (5) is connected to the control port of the main valve (2). One end of the bypass pipe (7) is connected to the pilot branch pipe (5), and the other end is connected to the main outlet pipe (4). The airflow control device (8) is installed on the bypass pipe (7), and the pilot pressure reducing valve (1) is installed on the pilot branch pipe (5). The airflow control device (8) is used to control the magnitude of the bidirectional airflow in the bypass pipe (7). The airflow control device (8) includes an airflow valve body (81) and a bidirectional valve disc (82). The airflow valve body (81) is provided with an airflow channel (83) and an installation channel (84). Both ends of the airflow channel (83) are connected to the bypass pipe (7). The installation channel (84) divides the airflow channel (83) into two sections. The bidirectional valve disc (82) is located in the installation channel (84), and both ends of the bidirectional valve disc (82) are... The bidirectional valve disc (82) is suspended between the two airflow channels (83) by connecting it to the airflow valve body (81) via an elastic element; the elastic element includes a spring one (85) and a spring two (86), and spring cavities (87) are respectively provided at both ends of the mounting channel (84). The ends of the spring one (85) and the spring two (86) that are far apart from each other are respectively connected to the inner wall of the spring cavity (87), and the ends of the spring one (85) and the spring two (86) that are close to each other are respectively connected to the bidirectional valve disc (82); the bidirectional valve disc (82) is provided with guide rods (88) on the surface facing the two airflow channels (83), and the guide rods (88) extend into the corresponding airflow channels (83). Inside, there is a gap between the outer wall of the guide rod (88) and the inner wall of the airflow channel (83) so that the airflow can enter the airflow channel (83); when the airflow on the side of spring one (85) is large, it pushes the bidirectional valve (82) to move downward, blocking the opening of the lower section of the airflow channel (83) and preventing the large airflow from entering the main outlet pipe (4), while allowing the small airflow to enter the main outlet pipe (4); when the airflow on the side of spring two (86) is large, it pushes the bidirectional valve (82) to move upward, blocking the opening of the upper section of the airflow channel (83) and preventing the large airflow from entering the pilot branch pipe (5) and the main valve control pipe (6), while allowing the small airflow to enter the pilot branch pipe (5) and the main valve control pipe (6).

2. The pressure regulation system for micro-airflow control according to claim 1, characterized in that: The pilot branch pipe (5), the main valve control pipe (6) and the bypass pipe (7) are connected by a tee connector (9).

3. The pressure regulation system for micro-airflow control according to claim 1, characterized in that: The main valve (2) is provided with a control chamber (21), a piston chamber (22) and a valve core chamber (23). The main valve control pipe (6) is connected to the control chamber (21) through a control port. A diaphragm (24) is provided between the control chamber (21) and the piston chamber (22). A piston (25) is provided in the piston chamber (22). A valve stem (26) and a valve core (27) are provided in the valve core chamber (23). The piston (25) is connected to the valve stem (26). The valve stem (26) is connected to the valve core (27). A valve port (28) is provided between the inlet and outlet of the main valve (2). The valve port (28) is located in the valve core chamber (23). The valve core (27) is used to open and close the valve port (28) to control the opening and closing of the inlet and outlet of the main valve (2).

4. The pressure regulation system for micro-airflow control according to claim 3, characterized in that: The piston chamber (22) is connected to the outlet of the main valve (2) through the exhaust passage (29).

5. The pressure regulation system for micro-airflow control according to claim 3, characterized in that: The control chamber (21) is provided with a baffle plate (20), and the diaphragm (24) is located between the baffle plate (20) and the piston (25). The baffle plate (20) is provided with a through flow channel (201), and the flow channel (201) faces the diaphragm (24).

Images