A double-spring electromagnetic proportional valve suitable for a semiconductor process flow control system

Abstract

The utility model discloses a kind of double-spring leaf type electromagnetic proportional valve suitable for semiconductor process flow control system, including valve body, shell and electromagnetic drive assembly;Upper valve cavity is equipped in valve body, is closed by upper valve cover;Lower valve cavity is equipped in shell, and valve seat is fixedly arranged inside;Valve body is sealingly connected with shell, upper and lower valve cavities are communicated by valve hole, movable valve core is equipped in valve hole, valve core one end and valve seat sealingly abut control fluid on-off;Electromagnetic drive assembly includes axially arranged moving iron core and static iron core, moving iron core one end and valve core abut, the other end is elastically connected with static iron core by small spring leaf, moving iron core and valve seat between are equipped with big spring leaf to provide reset force.The utility model also includes sealing valve core, sealing compression ring, moving iron core axial protruding structure, air inlet channel, air outlet channel and sealing framework, realize the technical effect of accurately controlling fluid flow, improve sealing performance and structural stability, suitable for the accurate control of gas or liquid flow in semiconductor manufacturing process.

Description

Technical Field

[0001] This utility model relates to the field of fluid control valves, specifically to a double-reed electromagnetic proportional valve suitable for semiconductor process flow control systems. Background Technology

[0002] Electromagnetic proportional valves, as devices capable of precisely controlling fluid flow, are widely used in semiconductor manufacturing, precision instruments, medical equipment, and other fields. With the continuous development of semiconductor technology, higher demands are placed on the accuracy, stability, and reliability of fluid control systems. Traditional electromagnetic proportional valves face challenges in precision control, response speed, and sealing performance when applied to semiconductor process flow control systems.

[0003] Currently, common electromagnetic proportional valves on the market mainly include direct-acting, pilot-operated, and combined types. Among them, direct-acting electromagnetic proportional valves are widely used in semiconductor process flow control systems due to their simple structure and fast response speed. For example, an electromagnetic proportional valve disclosed in CN119309013B includes a valve body, an electromagnetic assembly, a moving iron core, a sealing unit, a limiting element, and a first elastic element. The first elastic element applies a reverse force to the moving iron core, making the change in the resultant force of the electromagnetic force and the elastic force on the moving iron core tend to be linear, thereby improving the flow control accuracy.

[0004] Regarding pilot-operated diaphragm electromagnetic proportional valves, CN118088699A discloses a scheme that adds key components to the pilot-operated diaphragm electromagnetic valve and collects fluid data as a feedback signal, so as to realize the valve core opening degree is continuously adjustable within a certain range, and has the advantages of low control power, large flow rate, and strong impurity tolerance.

[0005] For applications requiring ultra-clean environments, CN112303247B proposes an ultra-clean proportional valve. It sets up a magnetic drive component by combining an embedded permanent magnet and an external control permanent magnet, and uses the principle of minimum magnetic resistance to open and close the valve port. It can achieve precise control of the valve port position, with a small actuation distance and fast response speed.

[0006] In terms of sealing performance, CN112833195A discloses a high-end, compact solenoid valve with zero leakage. By designing a new valve knife edge in the valve body and a direct-acting valve core component at the center of the upper part of the valve body, and designing a return spring at the center of the valve core component, the valve core component can be tightly closed with the valve knife edge when the solenoid coil is not energized, thus achieving a zero-leakage effect when the valve is closed.

[0007] To address the need for miniaturization, CN119244804B proposes a miniature proportional valve, which includes a valve body, a stationary armature, a coil, a valve core, a spring, and a positioning element. By using multiple positioning surfaces of the positioning element to simultaneously position each component, the control accuracy is reduced due to the large number of fit tolerances in traditional structures, resulting in better overall performance.

[0008] However, existing electromagnetic proportional valves still present some technical challenges when applied to semiconductor process flow control systems. These challenges primarily manifest in the following ways: In electromagnetic proportional valves, the displacement of the valve core during flow regulation is typically very small, only on the order of micrometers. When using a single-reed structure, the adjustment accuracy of the valve core displacement is limited by the stiffness of the reed; the deformation displacement accuracy of the reed is often greater than the system's required adjustment displacement accuracy, which greatly complicates the assembly and debugging of the electromagnetic proportional valve. This is especially true in semiconductor process flow control systems, where extremely high flow control accuracy is required, a requirement that the single-reed structure struggles to meet. Furthermore, existing electromagnetic proportional valves fail to achieve a good balance between sealing performance, structural stability, and adjustment accuracy, performing poorly particularly in semiconductor process applications requiring precise control of minute flow rates. Summary of the Invention

[0009] To address the technical problem that the motion displacement accuracy of the valve core in an electromagnetic proportional valve is limited by the stiffness of a single reed when adjusting flow, and to achieve the technical effects of improving the adjustment accuracy of the electromagnetic proportional valve and enhancing the stability of the balance system, this invention provides a double-reed electromagnetic proportional valve suitable for semiconductor process flow control systems.

[0010] The objective of this utility model is achieved through the following technical solution: a double-reed electromagnetic proportional valve suitable for semiconductor process flow control systems, comprising: The valve body has an upper valve chamber, and an upper valve cover is sealed to one axial end of the valve body to close the upper valve chamber. The housing has a lower valve chamber inside, a valve seat is fixedly installed in the lower valve chamber, and a valve body is sealed and installed on the upper part of the housing. The upper valve chamber and the lower valve chamber are connected through a valve hole. A valve core is movably installed in the valve hole. One axial end of the valve core is sealed and abuts against the valve seat to control the flow of fluid. An electromagnetic drive assembly includes a moving iron core and a stationary iron core arranged sequentially along the axial direction in the upper valve cavity. One end of the moving iron core is axially abutted against the valve core, and the other end is elastically connected to the stationary iron core through a small spring. A large spring is provided between the moving iron core and the valve seat to provide a restoring force so that the valve core remains in a sealed closed position when the power is off.

[0011] Furthermore, a sealing valve core is provided between the valve core and the valve seat, and the sealing valve core is disposed in the lower valve cavity to enhance the sealing performance.

[0012] Furthermore, a sealing ring is pressed between the valve seat and the inner wall of the lower valve chamber to achieve radial sealing between the valve seat and the housing.

[0013] Furthermore, the moving iron core has an axial protrusion at one end facing the stationary iron core, and the stationary iron core has a corresponding groove. The small spring has a central through hole, and the protrusion passes through the through hole and extends into the groove to limit the axial displacement range of the moving iron core.

[0014] Furthermore, the valve seat is provided with an air inlet channel along its axial direction, and the air inlet channel is connected to the lower valve chamber for introducing control fluid.

[0015] Furthermore, the upper valve cover is provided with an air outlet channel, which is connected to the upper valve chamber for outputting the regulated fluid.

[0016] Furthermore, a lower valve cover is sealed to the lower end of the valve body, and the upper end of the housing is fixedly connected to the valve body through the lower valve cover. A sealing skeleton is provided between the valve body and the lower valve cover to enhance the sealing performance and structural stability of the connection.

[0017] The beneficial effects of this invention are as follows: By employing a combination adjustment structure of large and small stiffness springs, this invention achieves fine adjustment of the valve core displacement, improving the adjustment accuracy by more than 20% compared to the traditional single-spring structure. Simultaneously, since the large and small springs can be adjusted separately, external factors such as vibration and particles affecting the valve core displacement will not simultaneously affect the force values ​​of both springs, thereby enhancing the stability of the balancing system. Furthermore, the dual-spring structure of this invention allows for the adjustment of the displacement deformation of the large-stiffness spring first, followed by the adjustment of the small-stiffness spring, during the assembly and debugging of the electromagnetic proportional valve. This effectively solves the technical challenge of micron-level displacement adjustment and greatly reduces the difficulty of assembly and debugging. Attached Figure Description

[0018] Figure 1 This is a cross-sectional view of the electromagnetic proportional valve of this utility model. Figure 2 This is another cross-sectional view of the electromagnetic proportional valve of this utility model; Figure 3 This is a three-dimensional structural schematic diagram of the electromagnetic proportional valve of this utility model. Figure 4 This is a three-dimensional structural schematic diagram of the electromagnetic proportional valve of this utility model from another perspective.

[0019] The attached diagram is labeled as follows: 1-valve seat, 111-inlet passage, 2-sealing valve core, 3-valve core, 4-large spring, 5-sealing pressure ring, 6-housing, 61-lower valve chamber, 7-moving iron core, 71-protrusion, 8-lower valve cover, 9-sealing skeleton, 10-valve body, 101-upper valve chamber, 11-small spring, 12-stationary iron core, 121-groove, 13-upper valve cover, 131-outlet passage. Detailed Implementation

[0020] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments and accompanying drawings. The content mentioned in the embodiments is not intended to limit the present invention.

[0021] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on the other component or indirectly on that other component.

[0022] When a component is said to be "connected to" another component, it can be directly connected to the other component or indirectly connected to that other component.

[0023] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0025] In the description of this application, "multiple" means two or more, unless otherwise expressly and specifically defined.

[0026] See Figure 1-4 A dual-reed electromagnetic proportional valve suitable for semiconductor process flow control systems includes a valve body 10, a housing 6, and an electromagnetic drive assembly.

[0027] The valve body 10 has an upper valve chamber 101, and an upper valve cover 13 is sealed to one axial end of the valve body 10. The upper valve cover 13 is used to close the upper valve chamber 101. The upper valve cover 13 has an exhaust channel 131, which communicates with the upper valve chamber 101 and is used to output the regulated fluid. When the electromagnetic proportional valve is working, the regulated fluid can be output through the exhaust channel 131, realizing precise control of the gas flow rate in the semiconductor process.

[0028] The housing 6 has a lower valve chamber 61, and a valve seat is fixedly installed in the lower valve chamber 61. The valve seat has an air inlet channel along its axial direction, which is connected to the lower valve chamber 61 to introduce control fluid. When it is necessary to control the gas flow rate, the control fluid can enter the lower valve chamber 61 through the air inlet channel and then be precisely adjusted according to the opening degree of the valve core 3. The valve body 10 is sealed and installed on the upper part of the housing 6, and the upper valve chamber 101 and the lower valve chamber 61 are connected through a valve hole. The valve core 3 is movably installed in the valve hole, and one axial end of the valve core 3 is sealed and abutted against the valve seat to control the flow of fluid. Under the balanced action of electromagnetic force and elastic force of large spring 4, the valve core 3 can achieve micron-level displacement control, thereby precisely adjusting the fluid flow rate.

[0029] A sealing valve core 2 is provided between the valve core 3 and the valve seat. The sealing valve core 2 is located in the lower valve cavity 61 to enhance the sealing performance. The sealing valve core 2 is made of a special material, which can maintain a good sealing effect under high pressure environment, prevent gas leakage, and ensure the strict requirements for gas purity and flow rate in semiconductor processes. A sealing pressure ring 5 is pressed between the valve seat and the inner wall of the lower valve cavity 61 to achieve radial sealing between the valve seat and the housing 6. The sealing pressure ring 5 can compensate for minor deformation caused by temperature changes or long-term use, and maintain the stable sealing performance of the system.

[0030] The electromagnetic drive assembly includes a moving iron core 7 and a stationary iron core 12 arranged axially within the upper valve chamber 101. One end of the moving iron core 7 axially abuts against the valve core 3, and the other end is elastically connected to the stationary iron core 12 via a small spring 11. The end of the moving iron core 7 facing the stationary iron core 12 has an axial protrusion 71, and the stationary iron core 12 has a corresponding groove 121. The small spring 11 has a central through hole, and the protrusion 71 passes through the through hole and extends into the groove 121 to limit the axial displacement range of the moving iron core 7. This design can prevent the moving iron core 7 from excessive displacement during operation, ensuring system stability and control accuracy. A large spring 4 is provided between the moving iron core 7 and the valve seat to provide a reset force, so that the valve core 3 remains in a sealed closed position when the power is off.

[0031] The lower end of the valve body 10 is sealed with a lower valve cover 8, and the upper end of the housing 6 is fixedly connected to the valve body 10 via the lower valve cover 8. A sealing skeleton 9 is provided between the valve body 10 and the lower valve cover 8 to enhance the sealing performance and structural stability of the connection. The sealing skeleton 9 can improve the rigidity of the overall structure, reduce vibration and deformation during operation, and extend the service life of the electromagnetic proportional valve.

[0032] When this double-reed electromagnetic proportional valve is in operation, the electromagnetic force generated by controlling the current in the electromagnetic coil acts on the moving iron core 7. The moving iron core 7 is stabilized at the force equilibrium point due to the combined action of the electromagnetic force and the elastic force provided by the large reed 4 and the small reed 11. Because of the double-reed structure, when the valve core 3 is affected by factors such as vibration or particles, the force value of the double reeds will not be affected simultaneously, thus enhancing the stability of the balancing system. At the same time, the double-reed structure improves the adjustment accuracy of the balancing system. During debugging, the displacement deformation of the large stiffness reed can be adjusted first, followed by the displacement deformation of the small stiffness reed. Compared with the single-reed structure, the accuracy can be improved by more than 20%, meeting the high-precision requirements of gas flow control in semiconductor processes.

[0033] When the electromagnetic coil is energized, the generated electromagnetic force overcomes the elastic force of the large reed 4, causing the moving iron core 7 to move the valve core 3 upward. The valve core 3 separates from the valve seat, and the fluid can flow from the air inlet channel through the gap between the valve seat and the valve core 3 into the upper valve chamber 101, and finally be output through the air outlet channel 131. By adjusting the current of the electromagnetic coil, the opening degree of the valve core 3 can be precisely controlled, thereby achieving precise regulation of the fluid flow rate. When the electromagnetic coil is de-energized, the elastic force of the large reed 4 causes the valve core 3 to return to the closed position, and the valve core 3 seals against the valve seat, cutting off the fluid flow.

[0034] The above embodiments are preferred implementations of this utility model. In addition, this utility model can also be implemented in other ways. Any obvious substitutions without departing from the concept of this utility model are within the protection scope of this utility model.

Claims

1. A double-reed electromagnetic proportional valve suitable for semiconductor process flow control systems, characterized in that, include: The valve body has an upper valve chamber, and an upper valve cover is sealed to one axial end of the valve body to close the upper valve chamber. The housing has a lower valve chamber inside, a valve seat is fixedly installed in the lower valve chamber, and a valve body is sealed and installed on the upper part of the housing. The upper valve chamber and the lower valve chamber are connected through a valve hole. A valve core is movably installed in the valve hole. One axial end of the valve core is sealed and abuts against the valve seat to control the flow of fluid. An electromagnetic drive assembly includes a moving iron core and a stationary iron core arranged sequentially along the axial direction in the upper valve cavity. One end of the moving iron core is axially abutted against the valve core, and the other end is elastically connected to the stationary iron core through a small spring. A large spring is provided between the moving iron core and the valve seat to provide a restoring force so that the valve core remains in a sealed closed position when the power is off.

2. The double-reed electromagnetic proportional valve suitable for semiconductor process flow control systems according to claim 1, characterized in that: A sealing valve core is provided between the valve core and the valve seat, and the sealing valve core is disposed in the lower valve cavity.

3. A double-reed electromagnetic proportional valve suitable for semiconductor process flow control systems according to claim 1, characterized in that: A sealing ring is pressed between the valve seat and the inner wall of the lower valve chamber to achieve radial sealing between the valve seat and the housing.

4. A double-reed electromagnetic proportional valve suitable for semiconductor process flow control systems according to claim 1, characterized in that: The moving iron core has an axial protrusion at one end facing the stationary iron core, and the stationary iron core has a corresponding groove. The small spring has a central through hole, and the protrusion passes through the through hole and extends into the groove to limit the axial displacement range of the moving iron core.

5. A double-reed electromagnetic proportional valve suitable for semiconductor process flow control systems according to claim 1, characterized in that: The valve seat is provided with an air inlet channel along its axial direction, and the air inlet channel is connected to the lower valve chamber for introducing control fluid.

6. A double-reed electromagnetic proportional valve suitable for semiconductor process flow control systems according to claim 1, characterized in that: The upper valve cover is provided with an air outlet channel, which is connected to the upper valve chamber for outputting regulated fluid.

7. A double-reed electromagnetic proportional valve suitable for semiconductor process flow control systems according to claim 1, characterized in that: The lower end of the valve body is sealed with a lower valve cover, and the upper end of the housing is fixedly connected to the valve body through the lower valve cover. A sealing skeleton is provided between the valve body and the lower valve cover to enhance the sealing performance and structural stability of the connection.

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