Double-runner ultra-precision control valve

Abstract

The invention discloses a double-flow-channel ultra-precision control valve which comprises a valve body, an executing mechanism, a flow dividing valve element and a flow control assembly. A first inflow channel, a first outflow channel, a second inflow channel and a second outflow channel are formed in the valve body; the flow dividing valve element is provided with two connecting channels communicating with the first inflow channel and the first outflow channel and communicating with the second inflow channel and the second outflow channel correspondingly. The flow control assembly comprises valve caps and a linkage rod, and the linkage rod is connected with the two valve caps and is in transmission connection with the execution mechanism so as to drive the two valve caps to act to control the first inflow channel, the first outflow channel, the second inflow channel and the second outflow channel to be connected and disconnected at the same time. The two bonnets are connected through the linkage rod, and the two bonnets can be driven to move up and down at the same time through one executing mechanism so as to control synchronous connection and disconnection of the connecting channel and the two flow channels; through the flow channel layout in a three-dimensional stacking mode, synchronous on-off control of a single execution mechanism on double flow channels is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of control valves, and more specifically to a dual-channel ultra-precision control valve. Background Art

[0002] In dual-fluid independent control scenarios such as semiconductor etching processes (e.g., Cl2 / H2 alternating gas supply systems) and biopharmaceutical processes (acid-base medium time-sharing switching), a dual-valve parallel connection scheme is required to achieve function expansion, resulting in system complexity, poor synchronism, and high costs.

[0003] The existing technologies have the following bottlenecks:

[0004] Spatial redundancy: The parallel layout significantly occupies the equipment space and is difficult to adapt to compact precision equipment (such as the immersion liquid path system of a lithography machine);

[0005] Dynamic control precision defect: The mechanical hysteresis between independent actuators leads to a timing deviation in the switching of the two-fluid channels, causing flow fluctuations, which directly threaten the film layer uniformity (±3% control requirement) of the semiconductor etching process and the pH value stability of the biopharmaceutical process.

[0006] In response to the above industry pain points, the research and development of an ultra-precision control valve with a dual-channel integrated architecture has become the breakthrough direction. Summary of the Invention

[0007] In view of this, the present invention provides a dual-channel ultra-precision control valve, which breaks through the functional limitations of traditional single-channel valves and adopts a three-dimensional stacked channel layout to achieve synchronous on-off control of a single actuator for two channels.

[0008] To achieve the above object, the present invention adopts the following technical solutions:

[0009] A dual-channel ultra-precision control valve, comprising:

[0010] A valve body, in which a first inflow channel, a first outflow channel, a second inflow channel, and a second outflow channel are opened;

[0011] An actuator, which is detachably connected to the upper end of the valve body;

[0012] A flow splitting valve core, which is fixed to the inner wall of the upper end of the valve body; two connection channels corresponding to and communicating with the first inflow channel, the first outflow channel, the second inflow channel, and the second outflow channel are opened in the flow splitting valve core;

[0013] A flow control component, the flow control component includes a valve bonnet and a linkage rod, the number of the valve bonnets is two and they are respectively arranged in the two connecting channels; the linkage rod connects the two valve bonnets and is transmission-connected to the actuator to drive the two valve bonnets to control the simultaneous opening and closing of the two connecting channels and the first inlet channel, the first outflow channel and the second inlet channel, the second outflow channel.

[0014] The beneficial effect of the technical solution of the present invention is that the two valve bonnets are connected by a linkage rod, and the linkage rod is transmitted to the piston of an actuator. The two valve bonnets can be driven up and down at the same time by an actuator. During the up and down movement of the two valve bonnets, the synchronous on and off of the two connecting channels and the upper and lower flow channels can be controlled; through the flow channel layout in a three-dimensional stacking manner, the synchronous on and off control of the two-way flow channels by a single actuator is realized.

[0015] Preferably, the two connecting channels are arranged in an upper and lower space; the two ends of the connecting channel located at the top are respectively connected to the outlet of the first inlet channel and the inlet of the first outlet channel; the two ends of the connecting channel located at the bottom are respectively connected to the outlet of the second inlet channel and the inlet of the second outlet channel; the medium flow direction in the first inlet channel and the first outlet channel is arranged perpendicular to the medium flow direction in the second inlet channel and the second outlet channel. The upper flow channel and the lower flow channel are connected by two connecting channels, and the two medium passages are arranged perpendicular to each other, which can ensure that the medium does not interfere with each other during the flow process.

[0016] Preferably, upper valve seats are fixed at both ends of the connecting channel located above the first inlet channel and the first outlet channel; lower valve seats are fixed at both ends of the connecting channel located below the second inlet channel and the second outlet channel; the two valve caps can move up and down to respectively abut against the upper surfaces of the upper valve seat and the lower valve seat to form a sealing surface. The valve seat is used to receive the valve cap, and a sealing surface is formed by the abutment between the valve seat and the valve cap, thereby realizing the opening and closing of the first inlet channel, the first outlet channel and the connecting channel, and the second inlet channel, the second outlet channel and the connecting channel.

[0017] Preferably, the top surfaces of the upper valve seat and the lower valve seat are both provided with diaphragms, and the two valve caps can move up and down to respectively press the two diaphragms, and the fluid channel is opened and closed by the compression fit between the diaphragms and the valve seats.

[0018] Preferably, the diaphragm is provided with an arc-shaped protrusion on the top surface corresponding to the upper valve seat or the lower valve seat; the arc-shaped protrusion can form an annular gap with the upper surface of the upper valve seat or the lower valve seat. When the valve seat presses the diaphragm, the arc-shaped protrusion and the valve seat are tightly matched and sealed to achieve the closure of the channel; when the valve seat is away from the diaphragm, the diaphragm is deformed under the action of its own elastic force, and an annular gap is formed between the arc-shaped protrusion and the valve seat to achieve the opening of the channel.

[0019] Preferably, a button is embedded in the bottom surface of the valve cap, and the button can be pressed and matched with the diaphragm. The movement of the valve cap can drive the button to move synchronously, and the button drives the deformation of the diaphragm to control the opening and closing of the channel.

[0020] Preferably, it also includes a valve stem; the valve bonnet includes an upper valve bonnet and a lower valve bonnet; the top surface of the upper valve bonnet is provided with a valve stem hole, and a mounting plate is fixed to the bottom surface; a mounting hole corresponding to the valve stem hole is provided on the panel of the mounting plate; the upper end of the linkage rod is embedded in the mounting hole, the valve stem is embedded in the valve stem hole and its upper end is screwed with the piston of the actuator to drive the linkage rod to drive the upper valve bonnet and the lower valve bonnet to move up and down synchronously. The actuator is in transmission connection with the valve stem, and the valve stem drives the linkage rod to realize the synchronous movement of the two valve bonnets, thereby realizing the synchronous opening and closing of the upper and lower flow channels.

[0021] Preferably, the lower end of the actuator is threadedly connected to the upper end of the valve body through a nut. The detachable connection method facilitates maintenance of the control valve.

[0022] It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a dual-channel ultra-precision control valve, which has the following beneficial effects:

[0023] 1. Structural innovation: Breaking through the functional limitations of traditional single-channel valves, adopting a three-dimensional stacked channel layout to achieve synchronous on-off control of dual-channel fluids by a single actuator;

[0024] 2. Extreme space utilization: Adopting three-dimensional stacked flow channel layout, the volume is reduced compared with the traditional double-valve parallel solution;

[0025] 3. Precise synchronous control: A single actuator drives the double-layer diaphragm to deform cooperatively, and the dual-path on-off synchronization error is smaller. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0027] Figure 1 Top view of the control valve provided by the present invention;

[0028] Figure 2 is Figure 1 A - A cross-sectional view in

[0029] Figure 3 is Figure 1 B - B cross-sectional view in

[0030] Figure 4 Cross-sectional view of the upper flow channel provided by the present invention;

[0031] Figure 5 Cross-sectional view of the lower flow channel provided by the present invention;

[0032] Figure 6 Schematic diagram of the upper valve cap structure provided by the present invention;

[0033] Figure 7 Schematic diagram of the upper button structure provided by the present invention;

[0034] Figure 8 Schematic diagram of the upper diaphragm structure provided by the present invention.

[0035] Among them,

[0036] 1 - valve body; 11 - first inflow channel; 111 - upper inlet annular gap; 12 - first outflow channel; 121 - upper outlet annular gap; 13 - second inflow channel; 131 - lower inlet annular gap; 14 - second outflow channel; 141 - lower outlet annular gap;

[0037] 2 - actuator;

[0038] 3 - nut;

[0039] 4 - valve stem;

[0040] 5 - connecting channel;

[0041] 6 - flow dividing valve core;

[0042] 7 - flow control assembly; 71 - upper valve cap; 711 - mounting groove; 712 - valve stem hole; 713 - mounting hole; 72 - upper button; 73 - upper diaphragm; 74 - lower valve cap; 75 - lower button; 76 - lower diaphragm; 77 - linkage rod;

[0043] 8 - upper valve seat;

[0044] 9 - lower valve seat. Specific implementation mode

[0045] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0046] Embodiment 1:

[0047] An embodiment of the present invention discloses a double-channel ultra-precision control valve, including:

[0048] A valve body 1, in which a first inflow channel 11, a first outflow channel 12, a second inflow channel 13, and a second outflow channel 14 are provided;

[0049] An actuator 2, which is detachably connected to the upper end of the valve body 1;

[0050] A flow splitting valve core 6, which is fixed to the inner wall of the upper end of the valve body 1; two connection channels 5 corresponding to and communicating with the first inflow channel 11, the first outflow channel 12, the second inflow channel 13, and the second outflow channel 14 are provided in the flow splitting valve core 6;

[0051] A flow control assembly 7, which includes a valve cap and a linkage rod 77. The number of valve caps is two and they are respectively arranged in the two connection channels 5; the linkage rod 77 connects the two valve caps and is in transmission connection with the actuator 2 to drive the two valve caps to act to control the simultaneous on-off of the two connection channels 5 with the first inflow channel 11, the first outflow channel 12, the second inflow channel 13, and the second outflow channel 14.

[0052] As Figure 1 shown, the valve body is integrally circular, the upper flow channel and the lower flow channel are coaxially arranged relative to the center of the valve body, and the lower flow channel is located inside the upper flow channel; the two connection channels on the flow splitting valve core are arranged at intervals up and down, and the upper flow channel and the lower flow channel are connected through the flow splitting valve core to ensure that the fluids between the two flow channels do not interfere with each other.

[0053] To further optimize the above technical solution and facilitate the maintenance operation of the control valve, the lower end of the actuator 2 is threadedly connected to the upper end of the valve body 1 through a nut 3.

[0054] In this embodiment, the two connection channels 5 are arranged at intervals up and down; the two ends of the upper connection channel 5 are respectively communicated with the outlet of the first inflow channel 11 and the inlet of the first outflow channel 12; the two ends of the lower connection channel 5 are respectively communicated with the outlet of the second inflow channel 13 and the inlet of the second outflow channel 14; the flow directions of the media in the first inflow channel 11 and the first outflow channel 12 are arranged perpendicular to the flow directions of the media in the second inflow channel 13 and the second outflow channel 14.

[0055] As Figures 1 to 3 shown, the first inflow channel, the upper connecting channel, and the first outflow channel are sequentially connected to form an upper flow channel; the second inflow channel, the lower connecting channel, and the second outflow channel are sequentially connected to form a lower flow channel. The flow directions of the media in the upper and lower flow channels are cross-shaped relative to the valve body.

[0056] The first inflow channel is provided with an upper inlet corresponding to the side wall of the valve body, and the first outflow channel is provided with an upper outlet corresponding to the side wall of the valve body; the upper inlet and the upper outlet are symmetric with respect to both sides of the valve body; the second inflow channel is provided with a lower inlet corresponding to the side wall of the valve body, and the second outflow channel is provided with a lower outlet corresponding to the side wall of the valve body; the lower inlet and the lower outlet are symmetric with respect to the other two sides of the valve body; wherein, the upper inlet, the upper outlet, the lower inlet, and the lower outlet are located on the same plane in the circumferential direction of the valve body, which can meet the introduction of two different media.

[0057] To further optimize the above technical solution and better achieve the synchronous on-off between the two flow channels, upper valve seats 8 are fixed at both ends of the connecting channel 5 located above corresponding to the first inflow channel 11 and the first outflow channel 12; lower valve seats 9 are fixed at both ends of the connecting channel 5 located below corresponding to the second inflow channel 13 and the second outflow channel 14; the two valve caps can move up and down and respectively abut against the upper surfaces of the upper valve seat 8 and the lower valve seat 9 to form sealing surfaces.

[0058] The upper valve seat and the lower valve seat correspond to both ends of the two-way connecting channel. When the valve caps abut against the upper surfaces of the upper valve seat and the lower valve seat to form sealing surfaces, the closing between the two-way connecting channel and the upper and lower flow channels can be realized respectively.

[0059] In this embodiment, a valve stem 4 is further included; the valve cap includes an upper valve cap 71 and a lower valve cap 74; a valve stem hole 712 is provided on the top surface of the upper valve cap 71, and a mounting plate is fixed on the bottom surface; mounting holes 713 corresponding to the valve stem hole 712 are provided on the panel of the mounting plate; the upper end of the linkage rod 77 is embedded in the mounting hole 713, and the valve stem 4 is embedded in the valve stem hole 712 and its upper end is screwed to the piston of the actuator 2 to drive the linkage rod 77 to drive the upper valve cap 71 and the lower valve cap 74 to move up and down synchronously.

[0060] As Figure 6 shown, the upper valve cap realizes the fastening with the valve stem through the valve stem hole. The actuator drives the valve stem to move up and down, so that the valve stem can drive the linkage rod and the two valve caps to move up and down synchronously during the up and down movement of the valve stem, thereby realizing the synchronous on-off between the two channels.

[0061] To further optimize the above technical solution, diaphragms are provided on the top surfaces of the upper valve seat 8 and the lower valve seat 9; the two valve caps can move up and down and respectively press the two diaphragms.

[0062] As Figure 4 and 5 shown, the upper surface of the upper valve seat 8 is provided with an upper diaphragm 72; the upper surface of the lower valve seat 9 is provided with a lower diaphragm 76; both the upper diaphragm 72 and the lower diaphragm 76 are located within the two-way connection channels, and both ends thereof correspond to the upper surfaces of the upper valve seat 8 and the lower valve seat 9.

[0063] When the upper valve cap and the lower valve cap move downward simultaneously, it will cause the upper diaphragm and the lower diaphragm to be tightly fitted between the upper valve seat and the lower valve seat, realizing the closure between the upper flow channel, the lower flow channel and the two-way connection channels; when the upper valve cap and the lower valve cap move upward simultaneously, the upper valve cap and the lower valve cap are respectively away from the upper diaphragm and the lower diaphragm, and the upper diaphragm and the lower diaphragm are deformed under the action of their own elasticity. Both the upper diaphragm and the lower diaphragm are located within the two-way connection channels and form gaps with the upper valve seat and the lower valve seat to satisfy the fluid flow, thereby realizing the opening of the passage between the laminar flow channel, the lower laminar flow channel and the two-way connection channels.

[0064] To further optimize the above technical solution, the diaphragm is provided with an arc-shaped protrusion corresponding to the top surface of the upper valve seat 8 or the lower valve seat 9; an annular gap can be formed between the arc-shaped protrusion and the upper surface of the upper valve seat 8 or the lower valve seat 9.

[0065] As Figure 8 shown, the arc-shaped protrusion on the diaphragm corresponds to the valve seat. When the diaphragm presses the arc-shaped protrusion, the arc-shaped protrusion abuts and seals against the valve seat; when the diaphragm is not pressurized, the arc-shaped protrusion will recover under the action of its own elasticity, and a gap is formed between the arc-shaped protrusion and the valve seat in this state to realize the fluid flow.

[0066] Specifically, as Figure 4 and 5 shown, an upper inlet annular gap 111 is formed between the arc-shaped protrusion on the upper diaphragm 73 and the upper valve seat 8 corresponding to the first inflow channel 11; an upper outlet annular gap 121 is formed between the arc-shaped protrusion on the diaphragm 73 and the upper valve seat 8 corresponding to the first outflow channel 12;

[0067] a lower inlet annular gap 131 is formed between the arc-shaped protrusion on the lower diaphragm 76 and the lower valve seat 9 corresponding to the second inflow channel 13; a lower outlet annular gap 141 is formed between the arc-shaped protrusion on the lower diaphragm 76 and the lower valve seat 9 corresponding to the second outflow channel 14;

[0068] The upper diaphragm 73 and the lower diaphragm 76 are both located in the connecting channel 5, and their two ends respectively correspond to two upper valve seats 8 and two upper valve seats 9; when the upper diaphragm 73 and the lower diaphragm 76 are pressed tightly, the arc-shaped protrusions will be contracted and pressed. At this time, the upper inlet annular gap 111, the upper outlet annular gap 121 and the lower inlet annular gap 131, the lower outlet annular gap 141 are respectively closed, and the passages between the first inflow channel 11, the first outflow channel 12 and the upper connecting channel 5 and between the second inflow channel 13, the second outflow channel 14 and the lower connecting channel 5 are closed; when the upper diaphragm 73 and the lower diaphragm 76 are not pressed tightly, at this time, the arc-shaped protrusions of the upper diaphragm 73 and the lower diaphragm 76 will recover under the action of their own elastic forces. At this time, the upper inlet annular gap 111, the upper outlet annular gap 121 and the lower inlet annular gap 131, the lower outlet annular gap 141 are opened, so that the passages between the first inflow channel 11, the first outflow channel 12 and the upper connecting channel 5 and between the second inflow channel 13, the second outflow channel 14 and the lower connecting channel 5 are opened. In this way, the synchronous on-off of the two flow channels is realized.

[0069] In some other specific embodiments, a button is embedded in the bottom surface of the valve cap, and the button can be in pressing fit with the diaphragm.

[0070] The button includes an upper button 72 and a lower button 75. The upper button 72 is detachably connected to the upper end of the flow dividing valve core 6 through a nut 3; the lower button 75 is located at the lower end of the flow dividing valve core 6, and the two are respectively located in the two-way connecting channels; an installation groove 711 is formed between the bottom surface of the upper valve cap 71 and the installation plate, the upper button 72 is embedded in the installation groove 711, the lower button 75 is embedded in the installation groove on the bottom surface of the lower valve cap 74, and the upper button 72 and the lower button 75 move up and down synchronously with the upper valve cap 71 and the lower valve cap 74; connecting rods are fixed on both the upper button 72 and the lower button 75. When the upper button 72 and the lower button 75 move downward, the connecting rods can simultaneously press the arc-shaped protrusions on the upper diaphragms 73 and the lower diaphragms 76 corresponding to the top surfaces of the two upper valve seats 8 and the two lower valve seats 9, so that the arc-shaped protrusions form a seal with the valve seats, thereby forming a sealing surface between the diaphragm and the valve seat.

[0071] Embodiment 2:

[0072] The embodiment of the present invention provides a control method for a two-channel ultra-precision control valve, which uses a two-channel ultra-precision control valve in Embodiment 1. The upper flow channel adopts a normally closed design, and one on-off cycle thereof includes the following four key processes:

[0073] 1), Un-supplied gas stage: The actuator is in a pressure-relief state, and the internal return spring applies a pre-tightening force through the valve stem. At this time, the valve stem axially presses the upper button, driving the upper diaphragm to be in close contact with the upper valve seat to ensure zero-leakage blockage;

[0074] 2) Air supply driving stage: When the air source is connected to the actuator, the internal piston assembly generates a vertical lifting action, driving the valve stem and the upper button to move upward;

[0075] 3) Fluid conduction state: As the upper button disengages from the sealing surface, the upper diaphragm deforms under the action of its own elastic restoring force, forming an upper inlet annular gap on the upper valve seat sealing surface. At this time, the fluid enters the upper inlet annular gap through the upper layer inlet via the first inflow channel. The fluid fills the connecting channel above (the fluid is located between the upper diaphragm and the bottom surface of the connecting channel), and the fluid enters the first outflow channel through the upper outlet annular gap and finally flows out from the upper layer outlet;

[0076] 4) Air loss stage: When the actuator is in a pressure relief state again, the internal spring and piston assembly generate a vertical downward movement, driving the valve stem and the upper button to move downward. At this time, the valve stem axially presses the upper button, driving the upper diaphragm to make sealing contact with the upper valve seat, and the fluid cannot enter the connecting channel through the upper inlet annular gap.

[0077] In this embodiment, since the linkage rod connects the upper valve cap in the upper flow channel and the lower valve cap in the lower flow channel, the working process of the second fluid is the same as that of the first fluid, and the lower flow channel is opened and closed simultaneously with the upper flow channel.

[0078] In this specification, the various embodiments are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0079] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A two-channel ultra-precision control valve, characterized in that, Comprising: A valve body (1), within which a first inflow channel (11), a first outflow channel (12), a second inflow channel (13) and a second outflow channel (14) are provided; An actuator (2), which is detachably connected to the upper end of the valve body (1); A flow splitting valve core (6), which is fixed to the inner wall of the upper end of the valve body (1); two connection channels (5) corresponding to and communicating with the first inflow channel (11), the first outflow channel (12) and the second inflow channel (13), the second outflow channel (14) respectively are provided within the flow splitting valve core (6); A flow control assembly (7), which includes a valve cap and a linkage rod (77), the number of the valve caps is two and they are respectively arranged within the two connection channels (5); the linkage rod (77) connects the two valve caps and is in transmission connection with the actuator (2) to drive the two valve caps to act so as to control the simultaneous on-off of the two connection channels (5) with the first inflow channel (11), the first outflow channel (12) and the second inflow channel (13), the second outflow channel (14).

2. The dual-flow ultra-precision control valve according to claim 1, wherein The two connection channels (5) are arranged at an upper and lower interval; the two ends of the upper connection channel (5) communicate with the outlet of the first inflow channel (11) and the inlet of the first outflow channel (12) respectively; the two ends of the lower connection channel (5) communicate with the outlet of the second inflow channel (13) and the inlet of the second outflow channel (14) respectively; the flowing directions of the media within the first inflow channel (11), the first outflow channel (12) are arranged perpendicular to the flowing directions of the media within the second inflow channel (13), the second outflow channel (14).

3. The dual-channel ultra-precision control valve according to claim 2, characterized in that, Upper valve seats (8) are fixed at the two ends of the upper connection channel (5) corresponding to the first inflow channel (11), the first outflow channel (12); lower valve seats (9) are fixed at the two ends of the lower connection channel (5) corresponding to the second inflow channel (13), the second outflow channel (14); the two valve caps can move up and down and abut against the upper surfaces of the upper valve seats (8) and the lower valve seats (9) respectively to form sealing surfaces.

4. The two-flow-channel ultra-precision control valve according to claim 3, characterized in that, Diaphragms are provided on the top surfaces of the upper valve seats (8) and the lower valve seats (9); the two valve caps can move up and down and press the two diaphragms respectively.

5. The double-flow-channel ultra-precision control valve according to claim 3, characterized in that, The diaphragms are provided with arc-shaped protrusions corresponding to the top surfaces of the upper valve seats (8) or the lower valve seats (9); annular gaps can be formed between the arc-shaped protrusions and the upper surfaces of the upper valve seats (8) or the lower valve seats (9).

6. The dual-channel ultra-precision control valve according to claim 5, wherein Buttons are embedded in the bottom surfaces of the valve caps, and the buttons can be in pressing fit with the diaphragms.

7. The dual-flow ultra-precision control valve according to claim 1, wherein It further includes a valve stem (4); the valve cap includes an upper valve cap (71) and a lower valve cap (74); a valve stem hole (712) is provided on the top surface of the upper valve cap (71), and a mounting plate is fixed to the bottom surface; a mounting hole (713) corresponding to the valve stem hole (712) is provided on the panel of the mounting plate; the upper end of the linkage rod (77) is embedded in the mounting hole (713), and the valve stem (4) is embedded in the valve stem hole (712) and its upper end is screwed to the piston of the actuator (2) to drive the linkage rod (77) to drive the upper valve cap (71) and the lower valve cap (74) to move up and down synchronously.

8. A dual-flow ultra-precision control valve according to claim 1, characterized in that, The lower end of the actuator (2) is threadedly connected to the upper end of the valve body (1) through a nut (3).

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