A micro pressure control valve

Abstract

The utility model discloses a micro-pressure control valve, including a valve seat, a valve port blocking mechanism and an actuator driving the valve port blocking mechanism to move; a first cavity and a second cavity are provided in the valve seat; the valve port blocking mechanism includes a shell, a diaphragm and a plug; the bottom of the shell is connected to the top of the valve seat; the diaphragm is arranged horizontally in the shell, a fluid channel is formed between the lower surface of the diaphragm and the inner wall of the shell, the plug is connected to the diaphragm, and the plug is located in the fluid channel; the upper opening of the first cavity is a valve port adapted to the plug; the second cavity is connected to the fluid channel; the actuator is installed on the top of the valve port blocking mechanism, and the driving end of the actuator passes through the shell and is connected to the diaphragm. The beneficial effects of the utility model are: a valve port blocking mechanism with a diaphragm is designed, and a diaphragm with a large surface area is used to amplify the pressure change, and small pressure changes can also be accurately fed back, which can greatly improve the accuracy of pressure control and improve the stability of pressure control.

Description

Technical Field

[0001] The utility model relates to a valve, in particular to a micro-pressure control valve. Background Art

[0002] At present, in the rod making process, some process reactions need to use micro-pressure control in order to better improve product quality and reduce the consumption of gas source materials. The dynamic control of hectopascal-level micro-pressure gas is mostly carried out by throttle valve control, that is, the throttle area is controlled according to the pressure. However, due to the poor linearity of the throttle valve's cut-off area, the poor accuracy of pressure regulation, and the influence of factors such as gas source temperature changes and pressure fluctuations, the stability of gas pressure is poor. If the pressure fluctuation is too large, it is easy to cause inconsistent product quality and poor uniformity in the axial direction of the preform.

[0003] Existing throttle valves mostly use metal valve bodies such as carbon steel and stainless steel, which are easily corroded by special gases, thus generating impurities and affecting the purity of the product. All valve body flow channels are now made of Teflon or fluororubber, which are acid and alkali resistant and not easy to react with raw materials.

[0004] Therefore, it is necessary to improve the prior art. Summary of the invention

[0005] The utility model aims to provide a micro-pressure control valve to improve the pressure regulation accuracy in view of the deficiencies in the prior art.

[0006] The technical solution adopted by the utility model is: a micro-pressure control valve, including a valve seat, a valve port blocking mechanism and an actuator for driving the valve port blocking mechanism to move;

[0007] The valve seat is provided with a first cavity and a second cavity;

[0008] The valve port blocking mechanism includes a housing, a diaphragm and a plug; the bottom of the housing is connected to the top of the valve seat;

[0009] The diaphragm is transversely arranged in the housing, a fluid channel is formed between the lower surface of the diaphragm and the inner wall of the housing, the plug is connected to the diaphragm, and the plug is located in the fluid channel; the upper opening of the first cavity is a valve port adapted to the plug; the second cavity is connected to the fluid channel;

[0010] The actuator is installed on the top of the valve port blocking mechanism, and the driving end of the actuator passes through the shell and is connected to the diaphragm.

[0011] According to the above scheme, the shell includes an upper cover plate and a lower cover plate; the lower cover plate is connected to the valve seat, and a fluid channel is formed between the lower cover plate and the diaphragm; the diaphragm is fixed between the upper cover plate and the lower cover plate; the diaphragm is connected to the plug through the upper pressure plate.

[0012] According to the above solution, the lower surface area of ​​the diaphragm is 100 to 110 times the cross-sectional area of ​​the valve port.

[0013] According to the above solution, the diaphragm is made of perfluororubber material.

[0014] According to the above scheme, the actuator includes a base, a screw, a nut, a spring and a spring seat; the upper and lower ends of the base are open, and the lower end of the base is connected to the shell; the upper part of the screw is limited by a retaining ring at the upper opening of the base, and the lower part of the screw is arranged in the base and cooperates with the nut in the base; the spring seat is arranged at the lower end of the nut seat, and the spring seat is located in the shell, and the spring seat is connected to the pressure plate and the plug through bolts; the lower part of the spring is arranged in the spring seat, the upper part of the spring is sleeved on the lower part of the screw, and the upper end of the spring is connected to the lower end face of the nut.

[0015] According to the above solution, the upper end of the screw is connected to the output end of the electric actuator.

[0016] According to the above solution, the electric actuator is a rotary electric actuator.

[0017] According to the above solution, the spring is a linear spring.

[0018] According to the above scheme, the pressure plate and the plug are connected by fastening bolts; the upper cover plate, the lower cover plate and the diaphragm are connected by connecting bolts.

[0019] The beneficial effects of the utility model are:

[0020] 1. The utility model designs a valve port plugging mechanism with a diaphragm. The gas lifts the diaphragm, and the diaphragm compresses the spring to drive the plug to move up, thereby increasing the outlet pipe channel area and releasing the gas pressure. When the gas pressure is lower than a predetermined value, the spring compresses the plug to move down, reducing the outlet channel area, and the inlet pressure rises accordingly. Such repeated automatic adjustment enables the inlet pressure to always maintain a stable pressure value, thereby achieving the purpose of stable pressure regulation.

[0021] 2. The utility model designs a valve port blocking mechanism with a diaphragm, which utilizes a large surface area of ​​the diaphragm to amplify the pressure change. Small pressure changes can also be accurately fed back, which can greatly improve the accuracy of pressure control and improve the stability of pressure control. At the same time, a linear spring is designed, and linear control is performed by the compression length of the spring. The valve has high linearity of force during the control process, and the pressure control is stable and accurate.

[0022] 3. The utility model adjusts the spring deformation by the rotation speed of the electric actuator, and finally balances the pressure of the target gas. The whole process can be controlled according to the process design pressure curve without human intervention. If the pressure of the target gas needs to be changed, the number of rotations of the electric actuator can be adjusted.

[0023] 4. The parts in contact with the fluid in the utility model are made of corrosion-resistant materials, which can be applied to the micro-pressure control of corrosive exhaust gas and ensure the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of a specific embodiment of the utility model.

[0025] Among them: 1. Connector; 2. Exhaust pipe; 3. Sealing ring; 4. Lower cover; 5. Diaphragm; 6. Upper cover; 7. Connecting bolts; 8. Base; 9. Fixing bolts; 10. Electric actuator; 11. Screw; 12. Retaining spring; 13. Nut; 14. Spring; 15. Spring seat; 16. Pressure plate; 17. Plug; 18. Valve seat; 19. Inlet pipe; 20. Fluid channel. DETAILED DESCRIPTION

[0026] In order to better understand the present invention, the present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0027] like Figure 1 The pressure control valve shown is essentially a micro-pressure control valve, comprising a valve seat 18, a valve port blocking mechanism and an actuator for driving the valve port blocking mechanism to move;

[0028] The valve seat 18 is provided with a first cavity and a second cavity, and the two cavities are respectively connected to corresponding external pipes;

[0029] The valve port blocking mechanism includes a housing, a diaphragm 5 and a plug 17; the bottom of the housing is connected to the top of the valve seat 18;

[0030] The diaphragm 5 is transversely arranged in the housing, and a fluid channel 20 is formed between the lower surface of the diaphragm 5 and the inner wall of the housing. The plug 17 is connected to the diaphragm 5, and the plug 17 is located in the fluid channel 20; the upper opening of the first cavity is a valve port adapted to the plug 17; the second cavity is connected to the fluid channel 20;

[0031] The actuator is installed on the top of the valve port sealing mechanism. The driving end of the actuator passes through the shell and is connected to the diaphragm 5, driving the valve port sealing mechanism to move up and down. When the plug 17 moves downward to seal the valve port, the first cavity is not connected to the fluid channel 20. When the plug 17 moves upward to separate from the valve port, the first cavity is connected to the fluid channel 20.

[0032] Preferably, the shell includes an upper cover plate 6 and a lower cover plate 4; the lower cover plate 4 is connected to the valve seat 18, and a fluid channel 20 is formed between the lower cover plate 4 and the diaphragm 5; the diaphragm 5 is fixed between the upper cover plate 6 and the lower cover plate 4; the diaphragm 5 is connected to the plug 17 through the upper pressure plate 16.

[0033] In the present invention, the pressing plate 16 is connected to the plug 17 by fastening bolts; the upper cover plate 6 , the lower cover plate 4 and the diaphragm 5 are connected by connecting bolts 7 .

[0034] Preferably, the lower surface area of ​​the diaphragm 5 is 100 to 110 times the cross-sectional area of ​​the valve port.

[0035] In the present invention, the lower surface of the diaphragm 5 is the working surface. By designing the diaphragm 5 with a large working surface, the force exerted on the diaphragm 5 is multiplied under the same pressure, achieving the effect of amplifying the pressure signal, so that micro-pressure control can be performed.

[0036] In the present invention, the diaphragm 5 is made of perfluoro rubber material. The diaphragm 5 is made of a relatively soft material. When the pressure in the chamber fluctuates, the diaphragm 5 deforms to adjust the volume of the chamber, thereby eliminating the pressure fluctuation.

[0037] Preferably, the actuator includes a base 8, a screw 11, a nut 13, a spring 14 and a spring seat 15; the upper and lower ends of the base 8 are open, and the lower end of the base 8 is connected to the shell (specifically connected to the upper cover plate 6); the upper part of the screw 11 is limited by the retaining ring 12 at the upper opening of the base 8, and the lower part of the screw 11 is arranged in the base 8 and cooperates with the nut 13 in the base 8; the spring seat 15 is arranged at the lower end of the nut 13 seat, and the spring seat 15 is located in the shell, and the spring seat 15 is connected to the pressure plate 16 and the plug 17 by bolts; the lower part of the spring 14 is arranged in the spring seat 15, the upper part of the spring 14 is sleeved on the lower part of the screw 11, and the upper end of the spring 14 is connected to the lower end surface of the nut 13.

[0038] In the present invention, the screw 11 is limited by the retaining spring 12 and the base 8, and can only move in the circumferential direction, and cannot move in the axial direction; at the same time, the nut 13 is also fixed in the circumferential direction, and can only move in the axial direction; when the screw 11 rotates, it drives the nut 13 to move up and down in the base 8. When the nut 13 moves downward, the compression spring 14 is deformed (conversely, the deformation is released), and the lower end of the spring 14 is fixed on the spring seat 15, and the spring seat 15 is connected to the diaphragm 5, so the force of the spring 14 will eventually be transmitted to the diaphragm 5, and the plug 17 at the lower end of the diaphragm 5 seals the valve port, so that the first cavity is not connected to the fluid channel 20, and the gas cannot pass through.

[0039] Preferably, the upper end of the screw rod 11 is connected to the output end of the electric actuator 10 .

[0040] In the present invention, the electric actuator 10 is a rotary electric actuator 10, which transmits the rotational motion to the screw 11, and the screw 11 and the nut 13 rotate relatively, and the nut 13 moves up and down accordingly in the base 8, thereby achieving the purpose of pre-compression of the spring 14. The electric actuator 10 is connected to the base 8 by a fixing bolt 9.

[0041] In the utility model, all components in contact with the fluid (such as the lower cover plate 4, the diaphragm 5, the air inlet pipe 19 and the air outlet pipe 2, the joint 1, the sealing ring, the plug 17, etc.) are made of corrosion-resistant materials of different hardness, such as polytetrafluoroethylene or fluororubber materials, which have good corrosion resistance and can adapt to various corrosive gases. At the same time, they are also compatible with ordinary gases, and the situation of exhaust gas corroding the valve body or pipeline is solved at a low cost.

[0042] The utility model is generally connected to a reaction tank and is used in situations where a slight positive pressure is required on the reaction tank. The first cavity and the second cavity are not connected to each other and are arranged on the left and right. The first cavity is an air outlet cavity, which is connected to the air outlet pipe 2 through a joint 1 (the joint 1 is sealed and connected to the outlet of the first cavity through a sealing ring 3); the second cavity is an air inlet cavity, which is connected to the air inlet pipe 19 through a joint 1 (the joint 1 is sealed and connected to the inlet of the second cavity through a sealing ring 3).

[0043] In this embodiment, the valve body is in a normally closed state when there is no air intake; the pre-compression amount of the spring 14 is adjusted, and when the valve body is put into use, the air intake pipe 19 is connected in series with the reaction tank, and the gas in the reaction tank enters the second cavity through the air intake pipe 19 and flows into the fluid channel 20, lifting the diaphragm 5. Since the diaphragm 5 has a large force area, it can also generate a large force at a lower pressure. The gas has a tendency to push the diaphragm 5 and the plug 17 to move upward (the upper cover plate and the lower cover plate are stationary). During the process of the plug 17 slowly moving upward, the flow area between the plug 17 and the first cavity will gradually increase, and the gas will be depressurized until the upward force of the diaphragm 5 is equal to the force of the spring 14, the valve body tends to be stable, the flow area will not change, a stable fluid channel 20 is formed, and the gas pressure will also stabilize. If the gas pressure in the reaction tank is lower than the target pressure, the electric actuator drives the screw 11 to rotate according to the pressure difference, and uses the nut 13 to press down the diaphragm 5. When the nut 13 moves downward, the compression spring 14 is deformed (conversely, the deformation is released). The lower end of the spring 14 is fixed on the spring seat 15, and the spring seat 15 is connected to the diaphragm 5. Therefore, the force of the spring 14 will eventually be transmitted to the diaphragm 5, and the plug 17 at the lower end of the diaphragm 5 will block the valve port, and the flow area of ​​the valve port will be reduced or even closed. At this time, the pressure in the reaction tank will passively rise until the pressure rises to balance the pressure of the spring 14, and the valve port will open again to form a new dynamic balance, and the actual gas pressure is equal to the target pressure; vice versa.

[0044] The utility model adopts a common linear spring 14. Since the force of the spring 14 is equal to the coefficient of the spring 14 multiplied by the compression amount, and the compression amount is proportional to the rotation speed of the electric actuator 10, the entire force is proportional to the rotation speed of the electric actuator 10; since the electric actuator 10 is counted by an encoder, the linearity of the force in the whole process is relatively high. The utility model can control the tiny pressure at the front end of the valve body. It only needs to design a suitable surface area of ​​the diaphragm 5 and the elastic coefficient of the spring 14 to control the pressure within hPa.

[0045] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0046] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. However, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A micro-pressure control valve, characterized in that: It includes a valve seat, a valve port blocking mechanism and an actuator for driving the valve port blocking mechanism to move; The valve seat is provided with a first cavity and a second cavity; The valve port blocking mechanism includes a housing, a diaphragm and a plug; the bottom of the housing is connected to the top of the valve seat; The diaphragm is transversely arranged in the housing, a fluid channel is formed between the lower surface of the diaphragm and the inner wall of the housing, the plug is connected to the diaphragm, and the plug is located in the fluid channel; the upper opening of the first cavity is a valve port adapted to the plug; the second cavity is connected to the fluid channel; The actuator is installed on the top of the valve port blocking mechanism, and the driving end of the actuator passes through the housing and is connected to the diaphragm; The actuator includes a base, a screw, a nut, a spring and a spring seat; the upper and lower ends of the base are open, and the lower end of the base is connected to the shell; the upper part of the screw is limited by a retaining ring at the upper opening of the base, and the lower part of the screw is arranged in the base and cooperates with the nut in the base; the spring seat is arranged at the lower end of the nut seat, and the spring seat is located in the shell, and the spring seat is connected to the pressure plate and the plug through bolts; the lower part of the spring is arranged in the spring seat, the upper part of the spring is sleeved on the lower part of the screw, and the upper end of the spring is connected to the lower end surface of the nut.

2. The micro-pressure control valve according to claim 1, characterized in that: The shell comprises an upper cover plate and a lower cover plate; the lower cover plate is connected to the valve seat, and a fluid channel is formed between the lower cover plate and the diaphragm; the diaphragm is fixed between the upper cover plate and the lower cover plate; the diaphragm is connected to the plug through the upper pressure plate.

3. The micro-pressure control valve according to claim 1 or 2, characterized in that: The lower surface area of ​​the diaphragm is 100 to 110 times the cross-sectional area of ​​the valve port.

4. The micro-pressure control valve according to claim 2, characterized in that: The diaphragm is made of perfluoro rubber material.

5. The micro-pressure control valve according to claim 1, characterized in that: The upper end of the screw rod is connected to the output end of the electric actuator.

6. The micro-pressure control valve according to claim 5, characterized in that: The electric actuator is a rotary electric actuator.

7. The micro-pressure control valve according to claim 5 or 6, characterized in that: The spring is a linear spring.

8. The micro-pressure control valve according to claim 2, characterized in that: The pressure plate is connected to the plug via fastening bolts; the upper cover plate, the lower cover plate and the diaphragm are connected via connecting bolts.

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