Solenoid valve, solenoid valve assembly, mass flow controller and electronic equipment

Abstract

The embodiment of the invention provides an electromagnetic valve, an electromagnetic valve assembly, a mass flow controller and electronic equipment, the electromagnetic valve comprises a magnetic conductive shell, a magnetic conductive column, a magnetic conductive valve element, a valve nozzle, a driving coil and a detection coil, the detection coil and a capacitor are connected in parallel to form a resonance circuit, and the first end of the resonance circuit is electrically connected with a controller through a resistor; the second end of the resonance circuit is grounded; the detection coil is used for receiving a first current signal provided by the controller to generate a first magnetic field, so that the detection coil and the magnetic conductive valve element are electromagnetically coupled, the controller obtains the voltage value of the first end, and the opening degree between the magnetic conductive valve element and the valve nozzle is obtained through the voltage value. Therefore, according to the electromagnetic valve, the electromagnetic valve assembly, the mass flow controller and the electronic equipment provided by the embodiment of the invention, the control stability and the response speed of the electromagnetic valve, the electromagnetic valve assembly, the mass flow controller and the electronic equipment on the mass flow of the fluid can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of solenoid valves, and in particular to a solenoid valve, a solenoid valve assembly, a mass flow controller and an electronic device. Background Art

[0002] A mass flow controller (MFC) can be used to measure and control the mass flow of gas or liquid.

[0003] In the related technology, the mass flow controller may include a gas channel, a mass flow sensor and a solenoid valve. The mass flow sensor and the solenoid valve are both arranged on the gas channel. The mass flow sensor is used to measure the mass flow rate of the gas in the gas channel. The mass flow rate of the gas in the gas channel can be controlled by adjusting the opening of the solenoid valve.

[0004] However, the solenoid valve has poor control stability over the mass flow rate of gas. Summary of the invention

[0005] In view of at least one of the above technical problems, an embodiment of the present application provides a solenoid valve, a solenoid valve assembly, a mass flow controller and an electronic device, which can improve the control stability of the solenoid valve and the mass flow controller on the mass flow of the fluid.

[0006] The embodiments of the present application provide the following technical solutions:

[0007] A first aspect of an embodiment of the present application provides a solenoid valve for working under the control of a controller component, wherein the controller component includes a controller, a resistor and a capacitor, wherein the controller is electrically connected to the resistor, and wherein the solenoid valve includes a magnetic shell, a magnetic column, a magnetic valve core, a valve nozzle, a drive coil and a detection coil, wherein the magnetic shell has a receiving cavity, wherein the magnetic column, the magnetic valve core, the valve nozzle, the drive coil and the detection coil are all located in the receiving cavity, wherein the magnetic column, the magnetic valve core and the valve nozzle are arranged in sequence along a first direction, wherein the magnetic column is connected to the magnetic shell, wherein the magnetic valve core is movably connected to the valve nozzle along the first direction, and wherein a flow channel is provided in the valve nozzle; wherein the detection coil is located on a side of the magnetic column facing the magnetic valve core, wherein the detection coil is connected in parallel with the capacitor to form a resonant circuit, wherein a first end of the resonant circuit is electrically connected to the controller via a resistor, and a second end of the resonant circuit is grounded; wherein the detection coil is used to receive a first current signal provided by the controller to generate a first magnetic field, so as to electromagnetically couple the detection coil with the magnetic valve core, thereby enabling the controller to obtain a voltage value at the first end, so as to obtain an opening between the magnetic valve core and the valve nozzle through the voltage value.

[0008] The solenoid valve provided in the embodiment of the present application forms a resonant circuit by connecting a detection coil in parallel with a capacitor, the first end of the resonant circuit is electrically connected to the controller through a resistor, and the second end of the resonant circuit is grounded; the detection coil is used to receive the first current signal provided by the controller to generate a first magnetic field, so that the detection coil and the magnetic valve core are electromagnetically coupled, so that the controller obtains the voltage value of the first end, so as to obtain the opening between the magnetic valve core and the valve mouth through the voltage value, and because there is a good correspondence between the mass flow rate and the opening of the fluid, the required target opening can be determined according to the required target mass flow rate, and the opening of the solenoid valve can be adjusted and controlled according to the difference between the actual opening detected and the target opening, until the difference between the actual opening detected and the target opening is less than the accuracy allowable value, thereby realizing the control of the opening, and then realizing the control of the mass flow. In addition, the frequency of the first current signal provided to the detection coil can be adjusted according to demand, so as to make the obtained opening result more accurate, and the detection coil is excited by the first current signal actively input, so that the anti-interference ability of the detection coil is strong.

[0009] In a possible implementation, the surface of the magnetic valve core facing the magnetic guide column is a non-metal surface, or the surface of the magnetic valve core facing the magnetic guide column is a metal surface. In this way, the magnetic valve core can be arranged in a variety of ways and can be applied to a variety of scenarios.

[0010] In a possible implementation, the solenoid valve includes a non-magnetic isolating member, which separates the accommodating chamber into a first accommodating chamber and a second accommodating chamber, the magnetic column, the driving coil and the detection coil are all located in the first accommodating chamber, and the magnetic valve core and the valve nozzle are all located in the second accommodating chamber. In this way, by providing the isolating member, the fluid can be prevented from entering the first accommodating chamber from the second accommodating chamber, the detection coil is physically isolated from the magnetic valve core by the isolating member, and the detection coil will not contact the magnetic valve core through the fluid, thereby preventing the fluid from causing adverse effects on the structural parts located in the first accommodating chamber.

[0011] In a possible implementation, the material of the isolating element includes a metal material; the thickness of the isolating element is less than or equal to 2 mm; and / or the frequency range of the first current signal is 10KHZ-100KHZ. In this way, the frequency range of the first current signal is 10KHZ-100KHZ, which makes it easier for the first magnetic field to penetrate the metal isolating element, which is conducive to reducing the influence of the isolating element on the first magnetic field. The thickness of the isolating element can be set to be smaller, and the smaller the thickness of the isolating element, the greater the electromagnetic force provided.

[0012] In a possible implementation, the material of the isolating element includes a non-metallic material, and the frequency of the first current signal is greater than or equal to 100 KHZ. Thus, when the isolating element is made of a non-metallic material, the frequency range of the first current signal is wider and can be applied to more scenarios.

[0013] In a possible implementation, the material of the isolation element includes a corrosion-resistant material; and / or the material of the magnetic valve core includes a corrosion-resistant material. In this way, the fluid can be prevented from corroding the isolation element and / or the magnetic valve core, thereby improving the isolation effect of the isolation element.

[0014] In a possible implementation, when the solenoid valve is in a closed state, the detection coil and the magnetic valve core have a first distance, and when the solenoid valve is in an open state, the detection coil and the magnetic valve core have a second distance, and the opening is equal to the difference between the first distance and the second distance.

[0015] In a possible implementation, the driving coil is sleeved on the outer periphery of the magnetic conductive column, and the controller is electrically connected to the driving coil. When the solenoid valve is in an open state, the controller is configured to provide a second current signal to the driving coil to generate a second magnetic field, and the second magnetic field acts on the magnetic conductive valve core so that the magnetic conductive valve core is subjected to a magnetic force in a first direction. In this way, under the action of the magnetic force, the magnetic conductive valve core moves toward or away from the driving coil, thereby changing the gap between the magnetic conductive valve core and the valve nozzle, that is, changing the opening between the magnetic conductive valve core and the valve nozzle, so as to control the mass flow of the fluid between the magnetic conductive valve core and the valve nozzle.

[0016] In a possible implementation, the solenoid valve includes an elastic member, one end of the elastic member is connected to the valve mouth, and the other end of the elastic member is connected to the magnetic valve core, and the elastic member is used to provide an elastic force toward the valve mouth to the magnetic valve core. In this way, the elastic member can be used to provide an elastic force toward the valve mouth to the magnetic valve core. When the solenoid valve is switched from an open state to a closed state, the drive coil has no second current signal, and the magnetic valve core moves toward the valve mouth under the action of the elastic member, so that the magnetic valve core contacts the valve mouth and closes the flow channel of the valve mouth.

[0017] In a possible implementation, the magnetic conductive column has a groove on one side facing the magnetic conductive valve core, and the detection coil is located in the groove. In this way, the groove can limit the detection coil and is also conducive to reducing the total volume of the magnetic conductive column and the detection coil.

[0018] A second aspect of an embodiment of the present application provides a solenoid valve assembly, comprising a controller assembly and the solenoid valve of the first aspect, wherein the controller assembly and the solenoid valve are electrically connected.

[0019] The solenoid valve assembly provided in the embodiment of the present application includes a solenoid valve, a resonance circuit is formed by connecting a detection coil in parallel with a capacitor, a first end of the resonance circuit is electrically connected to a controller through a resistor, and a second end of the resonance circuit is grounded; the detection coil is used to receive a first current signal provided by the controller to generate a first magnetic field, so that the detection coil and the magnetic valve core are electromagnetically coupled, so that the controller obtains a voltage value at the first end, so as to obtain the opening between the magnetic valve core and the valve mouth through the voltage value, and because there is a good correspondence between the mass flow rate and the opening of the fluid, the required target opening can be determined according to the required target mass flow rate, and the opening of the solenoid valve can be adjusted and controlled according to the difference between the actual opening detected and the target opening, until the difference between the actual opening detected and the target opening is less than the accuracy allowable value, thereby realizing the control of the opening, and then realizing the control of the mass flow. In addition, the frequency of the first current signal provided to the detection coil can be adjusted according to demand, so that the obtained opening result is more accurate, and the detection coil is excited by the first current signal actively input, so that the anti-interference ability of the detection coil is stronger.

[0020] The third aspect of an embodiment of the present application provides a mass flow controller, comprising: a controller component, a fluid channel, a mass flow sensor and the solenoid valve of the first aspect above, the controller component is electrically connected to the mass flow sensor and the solenoid valve, and the mass flow sensor is used to measure the mass flow rate of the fluid in the fluid channel.

[0021] The mass flow controller provided in the embodiment of the present application includes a solenoid valve, a resonance circuit is formed by connecting a detection coil in parallel with a capacitor, a first end of the resonance circuit is electrically connected to the controller through a resistor, and a second end of the resonance circuit is grounded; the detection coil is used to receive a first current signal provided by the controller to generate a first magnetic field, so that the detection coil and the magnetic valve core are electromagnetically coupled, so that the controller obtains a voltage value at the first end, so as to obtain the opening between the magnetic valve core and the valve mouth through the voltage value, and because there is a good correspondence between the mass flow rate and the opening of the fluid, the required target opening can be determined according to the required target mass flow rate, and the opening of the solenoid valve can be adjusted and controlled according to the difference between the actual opening detected and the target opening, until the difference between the actual opening detected and the target opening is less than the accuracy allowable value, thereby realizing the control of the opening, and then realizing the control of the mass flow. In addition, the frequency of the first current signal provided to the detection coil can be adjusted according to demand, so that the obtained opening result is more accurate, and the detection coil is excited by the first current signal actively input, so that the anti-interference ability of the detection coil is stronger.

[0022] In one possible implementation, the controller component is configured to use mass flow as an index to search for the opening of the solenoid valve in a first relationship table, wherein the first relationship table stores a correspondence between pre-calibrated mass flow and opening, and adjusts the opening of the solenoid valve according to the searched opening.

[0023] In this way, since the resonant circuit output response speed is fast, the control stability of the solenoid valve and the mass flow controller on the mass flow of the fluid can be improved.

[0024] In one possible embodiment, the controller component is configured to use the opening of the solenoid valve as an index to search for a second current signal of the solenoid valve in a second relationship table, wherein the second relationship table stores a correspondence between a pre-calibrated opening and a second current signal, and the opening of the solenoid valve is adjusted according to the searched second current signal.

[0025] In this way, according to the required target opening, the approximate target second current signal of the solenoid valve can be found in the second relationship table. The approximate target second current signal is closer to the target current signal. When the opening of the solenoid valve is controlled by the second current signal, the approximate target second current signal is adjusted to the target second current signal at a faster speed, thereby further reducing the closed-loop control response time of the valve core target opening, and further improving the control stability of the solenoid valve and the mass flow controller on the mass flow of the fluid.

[0026] A fourth aspect of an embodiment of the present application provides an electronic device, comprising the mass flow controller of the third aspect above.

[0027] The electronic device provided by the embodiment of the present application includes a mass flow controller, a resonance circuit is formed by connecting a detection coil in parallel with a capacitor, a first end of the resonance circuit is electrically connected to the controller through a resistor, and a second end of the resonance circuit is grounded; the detection coil is used to receive a first current signal provided by the controller to generate a first magnetic field, so that the detection coil and the magnetic valve core are electromagnetically coupled, so that the controller obtains a voltage value at the first end, so as to obtain the opening between the magnetic valve core and the valve mouth through the voltage value, and because there is a good correspondence between the mass flow rate and the opening of the fluid, the required target opening can be determined according to the required target mass flow rate, and the opening of the solenoid valve can be adjusted and controlled according to the difference between the detected actual opening and the target opening, until the difference between the detected actual opening and the target opening is less than the accuracy allowable value, thereby realizing the control of the opening, and then realizing the control of the mass flow. In addition, the frequency of the first current signal provided to the detection coil can be adjusted according to demand, so that the obtained opening result is more accurate, and the detection coil is excited by the first current signal actively input, so that the anti-interference ability of the detection coil is stronger. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present application 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 some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] Figure 1 A schematic diagram of the structure of the MFC provided in the embodiment of the present application;

[0030] Figure 2 Another structural schematic diagram of the MFC provided in the embodiment of the present application;

[0031] Figure 3 Another structural schematic diagram of the MFC provided in the embodiment of the present application;

[0032] Figure 4 A schematic diagram of the structure of the detection coil and the signal conditioning and control module provided in the embodiment of the present application;

[0033] Figure 5 A schematic diagram of the structure of a resonant circuit and a resistor provided in an embodiment of the present application;

[0034] Figure 6 A schematic diagram of the structure of a solenoid valve assembly provided in an embodiment of the present application;

[0035] Figure 7 A schematic diagram of a partially enlarged structure of a solenoid valve provided in an embodiment of the present application;

[0036] Figure 8 A schematic diagram of the structure of the detection coil and the magnetic valve core provided in the embodiment of the present application;

[0037] Fig. 9 Another structural schematic diagram of the detection coil and the magnetic valve core provided in the embodiment of the present application;

[0038] Fig.10 A relationship diagram between the voltage signal and the opening degree after the collection and processing provided in the embodiment of the present application;

[0039] Fig.11 A top view of a detection coil provided in an embodiment of the present application;

[0040] Fig.12 A schematic diagram of the structure of the detection coil, isolation element and magnetic valve core provided in an embodiment of the present application.

[0041] Description of reference numerals:

[0042] 100-mass flow controller; 101-mass flow sensor;

[0043] 102-fluid channel; 1021-detection channel;

[0044] 1022-diverter channel; 103-inlet;

[0045] 104- outlet; 105- solenoid valve assembly;

[0046] 110-control board; 111-first control module;

[0047] 112-a second control module; 113-a driving module;

[0048] 114-signal conditioning module; 115-flow calculation module;

[0049] 116- signal conditioning and control module; 1161- signal amplification unit;

[0050] 1162-signal detection unit; 1163-signal sampling and analysis processing unit;

[0051] 117-resonance circuit; 120-solenoid valve;

[0052] 121-magnetic conductive shell; 1211-first magnetic conductive shell;

[0053] 1212-a second magnetic conductive shell; 122-a magnetic conductive column;

[0054] 123-magnetic valve core; 124-elastic member;

[0055] 125-valve nozzle; 1253-third flow channel;

[0056] 1254- fourth flow channel; 126- driving coil;

[0057] 127- detection coil; 128- flow-through piece;

[0058] 1281-first flow channel; 1282-second flow channel;

[0059] 129-Isolator. DETAILED DESCRIPTION

[0060] In the related technology, the mass flow controller may include a gas channel, a mass flow sensor and a solenoid valve. The mass flow sensor and the solenoid valve are both arranged on the gas channel. The mass flow sensor is used to measure the mass flow rate of the gas in the gas channel. The mass flow rate of the gas in the gas channel can be controlled by adjusting the opening of the solenoid valve.

[0061] The solenoid valve includes a magnetic shell, which has a containing cavity. The drive coil, the magnetic core, the magnetic valve core and the gas nozzle are all located in the containing cavity. The magnetic core is connected to the magnetic shell, and the drive coil is wound around the magnetic core. The magnetic valve core is located between the gas nozzle and the magnetic core, and the magnetic valve core and the gas nozzle are connected by a spring. The electromagnetic attraction of the drive coil on the magnetic valve core can be changed by changing the current in the drive coil, thereby changing the opening between the magnetic valve core and the gas nozzle, thereby controlling the gas mass flow rate by controlling the opening.

[0062] However, the driving coil requires a strong magnetic field to drive the magnetic valve core to move, so it is necessary to construct a closed-loop magnetic circuit with magnetic conductive materials. Under the influence of the magnetic conductive materials inside and outside the driving coil, the driving coil will have hysteresis when generating a magnetic field. Due to the above-mentioned hysteresis effect of the solenoid valve, the difference in physical properties of different gases, the input gas pressure, the ambient temperature and other factors, the opening between the magnetic valve core and the gas nozzle does not have a good linear relationship with the current in the driving coil, and it is impossible to establish a direct relationship between the current of the driving coil and the valve core opening, so that it is impossible to achieve fast valve core opening control, and then it is impossible to quickly and accurately control the mass flow rate of the gas. For example, a thermal mass flow sensor can be set to detect the mass flow rate of the gas (i.e., the actual mass flow rate). When gases of different mass flow rates flow through the capillary of the thermal mass flow sensor, they can take away different amounts of heat, and the resistance value of the resistance wire of the thermal mass flow sensor changes. The mass flow rate of the gas flowing through can be obtained through the signal conditioning circuit and software processing. According to the difference between the measured actual mass flow and the target mass flow, the opening of the solenoid valve is controlled by the proportional-integral-derivative control (PID) algorithm until the difference between the actual mass flow and the target mass flow is less than the accuracy allowable value, thereby achieving mass flow control. However, during the measurement process of the thermal mass flow sensor, the resistance value of the resistance wire is changed by the current heating the resistance wire and the gas takes away the heat on the resistance wire. The change in heat to temperature stabilization is a slow process and takes a long time, so the response speed of the thermal mass flow sensor is slow, which brings great challenges to the rapid real-time control of the mass flow by the solenoid valve, resulting in poor stability in the control of the mass flow by the solenoid valve.

[0063] Based on at least one of the above technical problems, the embodiment of the present application provides a solenoid valve, a solenoid valve assembly, a mass flow controller and an electronic device, wherein a resonant circuit is formed by connecting a detection coil in parallel with a capacitor, the first end of the resonant circuit is electrically connected to the controller through a resistor, and the second end of the resonant circuit is grounded; the detection coil is used to receive a first current signal provided by the controller to generate a first magnetic field, so that the detection coil and the magnetic valve core are electromagnetically coupled, so that the controller obtains a voltage value at the first end, and obtains the opening between the magnetic valve core and the valve mouth through the voltage value. Since there is a good correspondence between the mass flow rate and the opening of the fluid, the required target opening can be determined according to the required target mass flow rate, and the opening of the solenoid valve can be adjusted and controlled according to the difference between the actual opening detected and the target opening, until the difference between the actual opening detected and the target opening is less than the accuracy allowable value, thereby realizing the control of the opening, and then realizing the control of the mass flow. In addition, the frequency of the first current signal provided to the detection coil can be adjusted according to demand, so that the obtained opening result is more accurate, and the detection coil is excited by the first current signal actively input, so that the anti-interference ability of the detection coil is stronger.

[0064] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0065] The following will be combined Figure 1-Figure 12 The solenoid valve, solenoid valve assembly, mass flow controller and electronic device provided in the embodiments of the present application are described.

[0066] The embodiment of the present application provides a mass flow controller 100, which can be used to control the mass flow of a fluid, wherein the fluid may include gas, liquid, etc. For example, the mass flow controller 100 can be applied to the semiconductor industry.

[0067] See also Figure 1 and Figure 2The mass flow controller 100 may include a fluid channel 102, a mass flow sensor 101 (e.g., a thermal mass flow sensor), a solenoid valve 120, and a controller component, wherein the controller component includes a controller, a capacitor, and a resistor. For example, the controller component may be a control board 110. The solenoid valve 120 and the control board 110 may be electrically connected, and the solenoid valve 120 and the control board 110 may together form a solenoid valve assembly 105. The control board 110 is electrically connected to the mass flow sensor 101. The mass flow sensor 101 is used to measure the mass flow rate of the fluid in the fluid channel 102, and the solenoid valve 120 may control the mass flow rate of the fluid in the fluid channel 102.

[0068] For example, see Figure 1 and Figure 2 The control board 110 may include a controller, and the controller may include a first control module 111, a drive module 113, a signal conditioning module 114, and a flow calculation module 115, wherein the mass flow sensor 101 and the first control module 111 are electrically connected via the signal conditioning module 114 and the flow calculation module 115. The solenoid valve 120 and the first control module 111 are electrically connected via the drive module 113. For example, the first control module 111 may be a PID control module.

[0069] For example, see Figure 1 and Figure 2 The two ends of the fluid channel 102 are respectively connected to the outlet 104 and the inlet 103, the mass flow sensor 101 can be arranged near the inlet 103, the solenoid valve 120 can be arranged near the outlet 104, and the fluid channel 102 and the outlet 104 can be connected through the solenoid valve 120. The fluid enters the detection channel 1021 and the diverter channel 1022 of the fluid channel 102 from the inlet 103, and the actual mass flow of the fluid can be measured by the mass flow sensor 101. The flow signal output by the mass flow sensor 101 passes through the signal conditioning module 114 and is sent to the flow solution module 115 in the control board 110 for real-time flow solution. The calculated flow is sent to the first control module 111 in the control board 110. The first control module 111 determines the current opening state of the solenoid valve 120 by the difference between the detected actual mass flow and the required target mass flow, and inputs a suitable drive signal (i.e., the second current signal) to the solenoid valve 120 through the drive module 113, so that the solenoid valve 120 is opened to a suitable opening until the measured actual mass flow is consistent with the target mass flow.

[0070] Exemplarily, the solenoid valve 120 includes an opening detector, which can be used to detect the opening of the magnetic valve core 123 and the valve mouth 125 ( Figure 7). With such a configuration, since there is a good correspondence between the mass flow rate of the fluid and the opening, the required target opening can be determined according to the required target mass flow rate, and the opening of the solenoid valve 120 can be adjusted and controlled according to the difference between the actual opening detected by the opening detector and the target opening, until the difference between the detected actual opening and the target opening is less than the accuracy allowable value, thereby achieving control of the opening, and then achieving control of the mass flow rate. Since the opening detector has a fast response speed, the control stability of the mass flow rate of the fluid by the solenoid valve 120 and the mass flow controller 100 can be improved. In addition, in order to ensure the accuracy of the mass flow control, the control board 110 also predicts the mass flow rate through the mass flow value detected by the mass flow sensor 101, and uses the predicted mass flow rate to correct the solenoid valve 120 to improve the accuracy of the mass flow control, solve the problem of poor control accuracy in different fluids and other scenes, and meet the requirements of ultra-high precision mass flow control scenes. That is, the opening is detected in real time by the opening detector to achieve fast closed-loop control of the MFC gas mass flow rate, and the mass flow sensor 101 can be used to achieve both fast and accurate closed-loop control of the fluid mass flow rate.

[0071] For example, when the gas type, pressure, and temperature conditions are known, the mass flow rate of the fluid and the opening can have a good correspondence. Of course, in other cases, the mass flow rate of the body and the opening can have a good correspondence, and this application does not limit this.

[0072] For example, the mass flow controller 100 may include a temperature sensor, which may be used to measure the temperature of the fluid. The temperature sensor may be electrically connected to the controller of the control board 110 .

[0073] For example, the mass flow controller 100 may include a pressure sensor, which may be used to measure the pressure of the fluid. The pressure sensor may be electrically connected to the controller of the control board 110 .

[0074] Exemplarily, the controller of the control board 110 is configured to use mass flow as an index in the first relationship table ( Figure 3) in the first relationship table, the correspondence between the pre-calibrated mass flow rate and the opening is stored, and the opening of the solenoid valve is adjusted according to the opening found. For example, according to the required target mass flow rate, the target opening of the solenoid valve 120 can be found in the first relationship table. Then, according to the difference between the actual opening detected by the opening detector and the target opening, the second current signal (i.e., the drive signal) is adjusted to control the opening of the solenoid valve 120 until the difference between the detected actual opening and the target opening is less than the accuracy allowable value, thereby achieving control of the opening and further achieving control of the mass flow rate. With such a configuration, since the resonant circuit output response speed is fast, the control stability of the mass flow rate of the fluid by the solenoid valve 120 and the mass flow controller 100 can be improved.

[0075] The first relationship table may be stored in the memory of the control board 110. The first relationship tables for different fluids, pressures, and temperatures may be different, and multiple first relationship tables may be established. In an embodiment in which a mass flow sensor 101 is provided, the target opening of the solenoid valve 120 may be corrected and controlled using the predicted mass flow, thereby improving the control accuracy of the mass flow.

[0076] Exemplarily, the controller of the control board 110 is configured to use the opening degree of the solenoid valve 120 as an index in the second relationship table ( Figure 3 ) in the solenoid valve 120, the second relationship table stores the correspondence between the pre-calibrated opening and the second current signal, and the opening of the solenoid valve is adjusted according to the second current signal that has been searched. The correspondence between the opening and the second current signal in the second relationship table is an approximate correspondence obtained without considering hysteresis. For example, according to the required target opening, the approximate target second current signal of the solenoid valve 120 can be searched in the second relationship table, and the approximate target second current signal is closer to the target current signal. When the opening of the solenoid valve 120 is controlled by the second current signal, the speed of adjusting the approximate target second current signal to the target second current signal is faster, thereby further reducing the closed-loop control response time of the valve core target opening, and further improving the control stability of the mass flow rate of the fluid by the solenoid valve 120 and the mass flow controller 100. The second relationship table can be stored in the memory of the control board 110.

[0077] It is understandable that the embodiment of the present application can establish a first relationship table, or can establish a first relationship table and a second relationship table at the same time. In the implementation of establishing the first relationship table and the second relationship table at the same time, the two relationship tables can be stored in the memory of the control board 110. When the mass flow controller 100 needs to control the mass flow of the fluid, the control board 110 detects the opening between the magnetic valve core 123 and the valve mouth 125 in real time, and queries the above two relationship tables to quickly perform closed-loop control on the fluid mass flow.

[0078] The solenoid valve 120 provided in the embodiment of the present application is described in detail below.

[0079] See also Figure 6 and Figure 7 , the solenoid valve 120 may include a magnetic housing 121, a magnetic column 122, a magnetic valve core 123, a valve nozzle 125 and a driving coil 126. The magnetic housing 121 has a receiving chamber, and the magnetic column 122, the magnetic valve core 123, the valve nozzle 125, the driving coil 126 and at least part of the opening detector are all located in the receiving chamber. For example, the magnetic column 122, the magnetic valve core 123 and the valve nozzle 125 may be arranged in sequence along the first direction A, the end of the magnetic column 122 away from the magnetic valve core 123 is connected to the magnetic housing 121, the magnetic valve core 123 is movably connected to the valve nozzle 125 along the first direction A, and a flow channel (the third flow channel 1253 and / or the fourth flow channel 1254) is provided in the valve nozzle 125, for example, the flow channel may pass through the valve nozzle 125 along the first direction A. The driving coil 126 may be sleeved on the outer periphery of the magnetic column 122.

[0080] Exemplarily, the solenoid valve 120 is electrically connected to the control board 110. The controller of the control board 110 is electrically connected to the drive coil 126. When the solenoid valve 120 is in an open state, the control board 110 is configured to provide a second current signal to the drive coil 126, and the second current signal is passed through the drive coil 126 to generate a second magnetic field, and the second magnetic field acts on the magnetic valve core 123, so that the magnetic valve core 123 is subjected to a magnetic force along the first direction A, for example, the magnetic valve core 123 is subjected to a magnetic force toward the drive coil 126, or the magnetic valve core 123 is subjected to a magnetic force away from the drive coil 126. The embodiment of the present application is described by taking the magnetic valve core 123 being subjected to a magnetic force toward the drive coil 126 as an example, so that the magnetic valve core 123 can move in a direction away from the valve mouth 125, so that the distance between the magnetic valve core 123 and the valve mouth 125 changes. When the solenoid valve 120 is in a closed state, the flow passage opening of the valve nozzle 125 facing the magnetic valve core 123 is covered and closed by the magnetic valve core 123 .

[0081] For example, see Figure 6 and Figure 7When the solenoid valve 120 is in an open state, the second magnetic field forms a closed magnetic circuit through the magnetic column 122, the detection coil 127, the isolating member 129, the air gap between the isolating member 129 and the magnetic valve core 123, the magnetic valve core 123, and the magnetic housing 121. Through the closed second magnetic field, the driving coil 126 generates an electromagnetic attraction on the magnetic valve core 123, and the magnitude of the electromagnetic attraction is proportional to the second current signal passing through the driving coil 126. Under the action of the electromagnetic attraction, the magnetic valve core 123 moves toward the driving coil 126, thereby changing the gap between the magnetic valve core 123 and the valve mouth 125, that is, changing the opening between the magnetic valve core 123 and the valve mouth 125, so as to control the mass flow of the fluid between the magnetic valve core 123 and the valve mouth 125.

[0082] For example, see Figure 2 and Figure 6 , the magnetic conductive shell 121 may include a first magnetic conductive shell 1211 and a second magnetic conductive shell 1212, and the second magnetic conductive shell 1212 is located in the first magnetic conductive shell 1211. The second magnetic conductive shell 1212 is arranged near the magnetic conductive valve core 123. The magnetic conductive shell 121 has an opening, which is connected to the accommodating cavity. The opening is arranged near the valve mouth 125, and a flow member 128 is provided at the opening. The fluid channel 102 is connected to the solenoid valve 120 through the flow member 128. The flow member 128 has a first flow channel 1281 and a second flow channel 1282. The flow channel of the valve mouth 125 includes a third flow channel 1253 and a fourth flow channel 1254. One end of the first flow channel 1281 near the valve mouth 125 is connected to the third flow channel 1253, and one end of the second flow channel 1282 near the valve mouth 125 is connected to the fourth flow channel 1254. Taking the fluid entering through the first flow channel 1281 as an example, the fluid sequentially passes through the first flow channel 1281, the third flow channel 1253, the gap between the magnetic valve core 123 and the valve mouth 125, the fourth flow channel 1254 and the second flow channel 1282. For example, the third flow channel 1253 can be an annular flow channel arranged outside the fourth flow channel 1254.

[0083] In some embodiments, see Figure 6 and Figure 7, the solenoid valve 120 may include an elastic member 124, for example, the elastic member 124 may be a metal reed. The elastic member 124 may be annular. One end of the elastic member 124 is connected to the valve mouth 125, and the other end of the elastic member 124 is connected to the magnetic valve core 123, and the magnetic valve core 123 is movably connected to the valve mouth 125 through the elastic member 124. For example, one end of the elastic member 124 is pressed and fixed between the second magnetic housing 1212 and the valve mouth 125, and the other end of the elastic member 124 is connected to the magnetic valve core 123. When the second current signal is passed through the driving coil 126, the magnetic valve core 123 drives the elastic member 124 to produce a deformation close to the direction of the driving coil 126, thereby changing the opening between the magnetic valve core 123 and the valve mouth 125. The elastic member 124 can be used to provide an elastic force toward the valve mouth 125 to the magnetic valve core 123. When the solenoid valve 120 switches from the open state to the closed state, the driving coil 126 has no second current signal, and the magnetic valve core 123 moves toward the valve mouth 125 under the action of the elastic member 124, so that the magnetic valve core 123 contacts the valve mouth 125 and closes the flow channel of the valve mouth 125. For example, when the solenoid valve 120 is in the closed state, the magnetic valve core 123 covers the fourth flow channel 1254, and the magnetic valve core 123 covers the third flow channel 1253 through the elastic member 124.

[0084] The opening detector provided in the application embodiment is described in detail below.

[0085] join Figure 6 and Figure 7 The opening detector may include at least one detection coil 127, which is located in the accommodating cavity and on the side of the magnetic column 122 facing the magnetic valve core 123. The control board 110 is electrically connected to the detection coil 127, and the controller of the control board 110 is configured to provide a first current signal to the detection coil 127. The first current signal in the detection coil 127 is used to generate a first magnetic field. The detection coil 127 is electromagnetically coupled with the magnetic valve core 123, and the controller of the control board 110 is configured to obtain the inductance value of the detection coil 127. The change in the inductance value has a good monotonic correlation with the distance between the magnetic valve core 123 and the detection coil 127, and the opening between the magnetic valve core 123 and the valve mouth 125 can be detected by calibration.

[0086] Exemplarily, the controller of the control board 110 is configured to use the inductance value as an index to search for the opening of the solenoid valve 120 in the third relationship table, and the third relationship table stores the correspondence between the pre-calibrated opening and the inductance value. Figure 8When the solenoid valve 120 is in a closed state, there is a first distance H1 between the detection coil 127 and the magnetic valve core 123. When the solenoid valve 120 is in an open state, there is a second distance H2 between the detection coil 127 and the magnetic valve core 123. The displacement △H of the magnetic valve core 123 can be equal to the difference between the first distance H1 and the second distance H2, that is, △H=H1-H2, where the displacement △H can be the opening. For example, the controller of the control board 110 detects the inductance value of the coil 127 in real time (equivalent to Figure 2 The detection coil 127 in the circuit outputs a signal), and the real-time opening of the electromagnetic valve 120 is found in the third relationship table according to the acquired inductance value, that is, the detection of the opening is realized.

[0087] Exemplarily, the displacement ΔH of the magnetic valve core 123 changes, resulting in a change in the inductance of the detection coil 127. The change in the inductance of the detection coil 127 causes a change in the voltage value output by the first end of the resonant circuit. The displacement ΔH of the magnetic valve core 123 can be known through the change in the voltage value. The controller of the control board 110 may include an electrically connected second control module 112 ( Figure 3 ) and signal conditioning and control module 116 ( Figure 6 ). The second control module 112 is electrically connected to the detection coil 127 through the signal conditioning and control module 116. Figure 4 and Figure 5 , the second control module 112 is used to provide a first current signal to the solenoid valve 120, and the signal conditioning and control module 116 detects the voltage change caused by the change in inductance value. The software can calculate the inductance value according to the voltage value detected by the signal conditioning and control module 116, and obtain the opening through the inductance value. For example, the voltage signal is processed by the signal amplification unit 1161, the signal detection unit 1162 and the signal sampling and analysis processing unit 1163 in the signal conditioning and control module 116 to obtain the inductance value. The controller component includes a controller, a resistor R and a capacitor C. The capacitor C is connected in parallel with the inductance of the detection coil 127. The capacitor C and the inductance of the detection coil 127 can jointly form a resonant circuit 117. The first end of the resonant circuit 117 is electrically connected to the controller through the resistor R, and the second end of the resonant circuit 117 is grounded. The controller provides a first current signal to the resonant circuit 117 through the resistor R, thereby providing a first current signal to the detection coil. The detection coil 127 receives the first current signal provided by the controller to generate a first magnetic field, so that the detection coil 127 and the magnetic valve core 123 are electromagnetically coupled, and the controller obtains the voltage value of the first end of the resonant circuit 117 to obtain the opening between the magnetic valve core 123 and the valve mouth 125 through the voltage value. Among them, the resistor R limits the current and divides the voltage of the input first AC signal, and the detection coil 127 is equivalent to an inductive device.

[0088] When the distance H ( Figure 7 ) changes, the inductance value of the detection coil 127 will change. When the parallel capacitor C and the inductance of the detection coil 127 form resonance, the impedance is maximum, and the output signal of the first end of the corresponding resonant circuit 117 is maximum. When the inductance value changes, the output voltage signal of the resonant circuit 117 will change. The signal sampling and analysis processing unit 1163 needs to use the calibration data to perform software calculation on the collected and processed voltage signal, and the calculated inductance signal is then corrected to achieve the collected and processed voltage signal ( Fig.10 ) and the displacement △H of the magnetic valve core 123 ( Fig.10 ) form a good linear relationship, so that the opening between the magnetic valve core 123 and the valve mouth 125 can be detected in real time.

[0089] Exemplarily, the detection coil 127 can be formed into a circular shape by winding a metal wire ( Fig.11 ), square or other shapes. To avoid increasing the magnetic resistance of the magnetic circuit too much, the winding thickness of the detection coil 127 can be set to be smaller. For example, a single-layer winding method can be used, and the thickness of the detection coil 127 can be no more than 1 mm.

[0090] Exemplarily, the second current signal may be a low-frequency signal, and the first current signal may be a high-frequency signal.

[0091] For example, the side of the magnetic conductive column 122 facing the magnetic conductive valve core 123 may have a groove, and the detection coil 127 is located in the groove. The groove can limit the detection coil 127 and is also conducive to reducing the total volume of the magnetic conductive column 122 and the detection coil 127.

[0092] The following describes a first implementation method for obtaining the inductance value of the detection coil 127 .

[0093] See also Figure 7 , the inductance value of the detection coil 127 can be obtained by the inductance generated in the detection coil 127 under the influence of the first magnetic field. The surface of the magnetic valve core 123 facing the detection coil 127 is a magnetic surface. The high-frequency first magnetic field generated by the first current signal in the detection coil 127, when the magnetic valve core 123 is subjected to the electromagnetic force of the driving coil 126, when the distance H between the magnetic valve core 123 and the detection coil 127 changes, the intensity of the high-frequency first magnetic field excited by the detection coil 127 will change, thereby causing the inductance of the detection coil 127 to change. For example, the surface of the magnetic valve core 123 facing the magnetic guide column 122 can be a non-metallic surface.

[0094] For details, see Figure 3 and Figure 7, the detection coil 127 generates a high-frequency first magnetic field under the control of the second control module 112. Under the action of the high-frequency first magnetic field, the detection coil 127 generates an equivalent high-frequency inductance, and the magnitude of the inductance value is proportional to the strength of the first magnetic field generated by the detection coil 127. Under the action of the electromagnetic force of the driving coil 126, the distance between the magnetic valve core 123 and the detection coil 127 changes, because the change in the distance between the magnetic valve core 123 and the detection coil 127 will change the excited first magnetic field, that is, the change in the distance will cause the intensity of the first magnetic field excited by the detection coil 127 to change, thereby causing the equivalent high-frequency inductance generated by the detection coil 127 to change.

[0095] See also Figure 6 , Figure 8 and Fig. 9 , the first current signal is provided to the detection coil 127 through the signal conditioning and control module 116. When the solenoid valve 120 is in the closed state, the distance between the detection coil 127 and the magnetic valve core 123 is H1. When the second current signal is provided to the driving coil 126, an upward attraction to the magnetic valve core 123 is generated, causing the elastic member 124 to deform, and the magnetic valve core 123 generates an upward displacement △H (i.e. H1-H2). At this time, the distance between the detection coil 127 and the magnetic valve core 123 becomes H2. By providing the first current signal (such as a 10KHZ square wave or a sine wave) to the detection coil 127, when the distance between the magnetic valve core 123 and the detection coil 127 changes, the intensity of the first magnetic field generated by the first current signal changes, which causes the inductance value of the detection coil 127 to change.

[0096] The opening between the magnetic valve core 123 and the valve mouth 125 is detected by the detection coil 127. The detection speed of the opening is fast (less than 1ms), and the control board 110 can quickly control the electromagnetic valve 120 according to the opening value. The control current of the drive coil 126 is determined according to the detected ΔH (opening value), so as to achieve accurate and fast control of the valve opening, thereby improving the response speed of the MFC to the gas mass flow control.

[0097] A second implementation method of obtaining the inductance value of the detection coil 127 is described below.

[0098] See also Figure 7 The surface of the magnetic valve core 123 facing the magnetic guide column 122 is a metal surface. The first magnetic field acts on the metal surface to form eddy currents on the metal surface. The eddy currents generate eddy current magnetic fields. The inductance value can be the inductance generated in the detection coil 127 under the influence of the eddy current magnetic fields. For example, the material of the magnetic valve core 123 can include metal materials.

[0099] The first magnetic field excited by the detection coil 127 induces eddy currents on the metal surface of the magnetic valve core 123. The size of the eddy current is related to the distance between the metal surface and the detection coil 127. The closer the distance is, the stronger the eddy current induced on the metal surface. The eddy current induced on the metal surface will generate an alternating eddy current magnetic field, which will affect the high-frequency equivalent inductance of the detection coil 127. The principle is similar to that of the first embodiment and will not be repeated here.

[0100] The isolation member 129 provided in the application embodiment is described below.

[0101] See also Figure 7 and Fig.12 , the solenoid valve 120 may include a non-magnetic isolating member 129, which divides the accommodating chamber into a first accommodating chamber and a second accommodating chamber. The magnetic column 122, the driving coil 126 and the detection coil 127 may all be located in the first accommodating chamber, and the magnetic valve core 123 and the valve mouth 125 may all be located in the second accommodating chamber. By providing the isolating member 129, the fluid may be prevented from entering the first accommodating chamber from the second accommodating chamber. The detection coil 127 is physically isolated from the magnetic valve core 123 by the isolating member 129, and the detection coil 127 will not contact the magnetic valve core 123 through the fluid, thereby preventing the fluid from causing adverse effects on the structural components (e.g., the detection coil 127 and the driving coil 126) located in the first accommodating chamber. For example, the fluid may be corrosive, and by providing each isolating member 129, the detection coil 127 and the driving coil 126 may be prevented from failing due to fluid corrosion.

[0102] Exemplarily, the isolating member 129 is connected to the second magnetic conductive shell 1212, so that the isolation effect between the first accommodating chamber and the second accommodating chamber is better, and the leakage of the fluid in the second accommodating chamber can be prevented. For example, the isolating member 129 is connected to the second magnetic conductive shell 1212 by welding.

[0103] In the embodiment where the fluid is corrosive, the drive coil 126, the detection coil 127 and the fluid are isolated by the isolation member 129. The isolation member 129 can be made of a non-magnetic and corrosion-resistant material, thereby preventing the fluid from corroding the isolation member 129 and improving the isolation effect of the isolation member 129. Similarly, the material of the magnetic valve core 123 can include a corrosion-resistant material, and at least part of the surface of the magnetic valve core 123 can be a corrosion-resistant surface. For example, the surface of the magnetic valve core 123 facing the detection coil 127 is made of a magnetic and corrosion-resistant material (such as KM45 stainless steel).

[0104] In the implementation method of obtaining the inductance value of the detection coil 127 as the inductance value generated by the first magnetic field in the detection coil 127, the material of the isolation member 129 can be a metal material (for example, 316L stainless steel). When the isolation member 129 is made of metal material, the isolation member 129 will also generate an alternating magnetic field under the action of the first magnetic field, which may affect the inductance value of the detection coil 127. The greater the thickness of the isolation member 129, the smaller the resistance of the isolation member 129, the stronger the alternating electromagnetic signal induced by the isolation member 129, and the greater the impact on the inductance value. Therefore, it is necessary to control the thickness of the isolation member 129. For example, the thickness of the isolation member 129 does not exceed 2mm, so as to avoid the isolation member 129 affecting the signal sensitivity detected by the detection coil 127. Among them, the thickness of the isolation member 129 can be set according to actual needs. The smaller the thickness of the isolation member 129, the greater the electromagnetic force provided. Therefore, the thickness of the isolation member 129 can be set to be smaller. Of course, the thickness of the isolation member 129 cannot be set too small to prevent the isolation member 129 from being too thin and having the risk of rupture. Therefore, the minimum thickness of the isolation member 129 needs to take into account the use environment of the isolation member 129, including air pressure, overall machine size, etc.

[0105] The frequency range of the first current signal may be 10 KHZ-100 KHZ, so that the first magnetic field can more easily penetrate the metal isolation member 129 , which is beneficial to reducing the influence of the isolation member 129 on the first magnetic field.

[0106] In an implementation in which the inductance value of the detection coil 127 is obtained as the inductance generated by the first magnetic field in the detection coil 127, the material of the isolation member 129 may be a non-metallic material (e.g., polytetrafluoroethylene, or PTFE for short). The frequency range of the first current signal may be 10KHZ-100KHZ. In addition, when the isolation member 129 is made of a non-metallic material, the frequency of the first current signal in the detection coil 127 may be higher, for example, greater than or equal to 100KHZ (e.g., 100KHZ-1MHZ). Therefore, when the isolation member 129 is made of a non-metallic material, the frequency range of the first current signal is wider and can be applied to more scenarios.

[0107] In the implementation of obtaining the inductance value of the detection coil 127 as the inductance value of the eddy current magnetic field generated in the detection coil 127, the material of the isolation member 129 can be a non-metallic material (for example, PTFE). The frequency range of the first current signal can be 10KHZ-100KHZ, or can be greater than or equal to 100KHZ (for example, 100KHZ-1MHZ). In addition, since the isolation member 129 is a non-metallic material, it can be avoided that the interference eddy current is induced on the isolation member 129 to affect the eddy current magnetic field generated by the metal surface of the magnetic valve core 123.

[0108] In addition, an embodiment of the present application further provides an electronic device, and the electronic identification may include the mass flow controller in the above embodiment. For example, the electronic device may include a semiconductor device.

[0109] It should be noted here that the numerical values ​​and numerical ranges involved in the embodiments of the present application are approximate values. Due to the influence of the manufacturing process, there may be a certain range of errors, which can be considered negligible by those skilled in the art.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A solenoid valve, characterized in that: Used to work under the control of a controller component, the controller component includes a controller, a resistor and a capacitor, the controller is electrically connected to the resistor, the solenoid valve includes a magnetic shell, a magnetic column, a magnetic valve core, a valve nozzle, a drive coil and a detection coil, the magnetic shell has a containing cavity, the magnetic column, the magnetic valve core, the valve nozzle, the drive coil and the detection coil are all located in the containing cavity, the magnetic column, the magnetic valve core and the valve nozzle are arranged in sequence along a first direction, the magnetic column is connected to the magnetic shell, the magnetic valve core is movably connected to the valve nozzle along the first direction, and a flow channel is provided in the valve nozzle; Wherein, the detection coil is located on the side of the magnetic column facing the magnetic valve core, the detection coil is connected in parallel with the capacitor to form a resonant circuit, the first end of the resonant circuit is electrically connected to the controller through the resistor, and the second end of the resonant circuit is grounded; the detection coil is used to receive a first current signal provided by the controller to generate a first magnetic field, so that the detection coil and the magnetic valve core are electromagnetically coupled, so that the controller obtains the voltage value of the first end, so as to obtain the opening between the magnetic valve core and the valve mouth through the voltage value.

2. The solenoid valve according to claim 1, characterized in that: The surface of the magnetic valve core facing the magnetic pillar is a non-metallic surface.

3. The solenoid valve according to claim 1, characterized in that: The surface of the magnetic valve core facing the magnetic pillar is a metal surface.

4. The solenoid valve according to any one of claims 1 to 3, characterized in that: The solenoid valve includes a non-magnetic isolating member, which separates the accommodating chamber into a first accommodating chamber and a second accommodating chamber. The magnetic column, the driving coil and the detection coil are all located in the first accommodating chamber, and the magnetic valve core and the valve nozzle are both located in the second accommodating chamber.

5. The solenoid valve according to claim 4, characterized in that: The material of the isolation member includes a metal material; The thickness of the isolating element is less than or equal to 2 mm; and / or the frequency range of the first current signal is 10 KHZ-100 KHZ.

6. The solenoid valve according to claim 4, characterized in that: The material of the isolation element includes non-metallic material, and the frequency of the first current signal is greater than or equal to 100 KHZ.

7. The solenoid valve according to claim 4, characterized in that: The material of the isolation member includes a corrosion-resistant material; And / or, the material of the magnetically conductive valve core includes a corrosion-resistant material.

8. The solenoid valve according to any one of claims 1 to 3, characterized in that: When the solenoid valve is in a closed state, the detection coil and the magnetic valve core have a first distance, and when the solenoid valve is in an open state, the detection coil and the magnetic valve core have a second distance, and the opening is equal to the difference between the first distance and the second distance.

9. The solenoid valve according to any one of claims 1 to 3, characterized in that: The drive coil is sleeved on the outer circumference of the magnetic conductive column, and the controller is electrically connected to the drive coil. When the solenoid valve is in an open state, the controller is configured to provide a second current signal to the drive coil to generate a second magnetic field. The second magnetic field acts on the magnetic conductive valve core so that the magnetic conductive valve core is subjected to a magnetic force along the first direction.

10. The solenoid valve according to any one of claims 1 to 3, characterized in that: The solenoid valve comprises an elastic member, one end of which is connected to the valve mouth, and the other end of which is connected to the magnetic valve core, and the elastic member is used to provide an elastic force to the magnetic valve core toward the valve mouth.

11. The solenoid valve according to any one of claims 1 to 3, characterized in that: A side of the magnetic conductive column facing the magnetic conductive valve core has a groove, and the detection coil is located in the groove.

12. A solenoid valve assembly, characterized in that: It comprises a controller component and the solenoid valve described in any one of claims 1 to 11, wherein the controller component and the solenoid valve are electrically connected.

13. A mass flow controller, characterized in that: include: A controller component, a fluid channel, a mass flow sensor and a solenoid valve as described in any one of claims 1 to 11, wherein the controller component is electrically connected to the mass flow sensor and the solenoid valve, and the mass flow sensor is used to measure the mass flow of the fluid in the fluid channel.

14. The mass flow controller according to claim 13, characterized in that: The controller component is configured to use mass flow as an index to search for the opening of the solenoid valve in a first relationship table, wherein the first relationship table stores a correspondence between pre-calibrated mass flow and opening, and adjust the opening of the solenoid valve according to the searched opening.

15. The mass flow controller according to claim 13, characterized in that The controller component is configured to use the opening of the solenoid valve as an index to search for a second current signal of the solenoid valve in a second relationship table, wherein the second relationship table stores a correspondence between a pre-calibrated opening and a second current signal, and adjust the opening of the solenoid valve according to the searched second current signal.

16. An electronic device, characterized in that: The mass flow controller comprises any one of claims 13 to 15.

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