Rapid calibration control system and device for multi-stage multi-unit mass flow controller

Abstract

This invention discloses a rapid calibration control system and device for multi-stage, multi-connected mass flow controllers. The system includes a multi-stage branch pipeline module, a central core control and adjustment module, a digital monitoring and testing module, and a safety protection module. It achieves batch synchronous closed-loop calibration of multiple parallel mass flow controllers by first independently pre-calibrating each electric flow distribution valve in the secondary pipeline and establishing a flow model, and then coordinating the control and adjustment of each flow based on this model. The digital monitoring and testing module serves as a dedicated testing device for the system, collecting flow data in real time and feeding it back to the control core. The safety protection module acts as a status monitoring and protection unit for the system, realizing full-process operational status monitoring. This invention solves the problems of mutual interference and low efficiency in parallel calibration flow, improving the consistency, accuracy, and automation level of calibration.

Description

Technical Field

[0001] This application relates to the field of fluid control or regulation system technology, and more specifically, to a rapid calibration control system and device for a multi-stage, multi-connected mass flow controller. Background Technology

[0002] As a core component in the field of fluid control, the accuracy of flow controllers directly determines the operational quality in scenarios such as industrial production and scientific research experiments. Before leaving the factory, they must undergo strict calibration to ensure that their performance meets the standards. The calibration process relies on a reliable control or regulation system, as well as supporting functional units and monitoring and testing devices. Existing calibration-related control / regulation systems suffer from several pressing problems: Traditional calibration equipment control / regulation systems often employ single-channel or limited multi-channel architectures with simple functional unit configurations, lacking the collaborative control mechanisms required for batch calibration. The number of units calibrated at a time is limited, leading to excessively long calibration cycles that fail to match production capacity when facing mass production demands. While some multi-unit calibration solutions attempt to achieve simultaneous calibration of multiple devices, the corresponding control / regulation systems lack optimized functional unit collaboration, fail to design precise adjustment mechanisms for differences in pipeline resistance and uneven fluid distribution, and have incomplete monitoring and testing coverage. This results in poor consistency in the calibration accuracy of mass flow controllers at different workstations, requiring frequent rework and increasing production costs. Furthermore, the monitoring and testing devices in the testing phase generally adopt a full-inspection mode, with limited functionality. This not only consumes significant time and standard gas resources but also relies on manual analysis of test data, lacking efficient digital monitoring and testing and batch judgment functional units. Existing multi-connection calibration-related control / regulation systems mostly focus on basic parallel architecture design, failing to address issues such as independent valve pre-calibration control, coordinated regulation based on flow uniformity, and optimization of monitoring and testing functional units corresponding to batch error estimation. They cannot balance calibration efficiency, accuracy, and testing costs, making it difficult to meet the requirements of large-scale, high-precision mass flow controller calibration for control / regulation systems, their functional units, and monitoring and testing devices. Therefore, there is an urgent need for a technical solution that optimizes the control / regulation system architecture, improves the configuration of functional units, and enhances monitoring and testing capabilities. Summary of the Invention

[0003] The purpose of this application is to provide a rapid calibration control system and device for multi-stage multi-connected mass flow controllers, which has the advantages of improving calibration efficiency, ensuring consistency of batch calibration accuracy, and reducing testing costs.

[0004] This application provides a rapid calibration control system for a multi-stage, multi-connected mass flow controller, including a multi-stage branch pipeline module, a central core control and regulation module, a digital monitoring and testing module, and a safety protection module;

[0005] The multi-stage distribution pipeline module includes a primary main pipeline, a secondary distribution pipeline, and a tertiary distribution pipeline connected in series. The primary main pipeline is used to connect to a standard gas source and is equipped with a pressure stabilizing and standard flow detection unit. The secondary distribution pipeline has several independent branches, each equipped with a controllable electric precision flow distribution valve. The tertiary distribution pipeline includes multiple parallel branches, each with an interface for a mass flow controller to be calibrated.

[0006] The central core control and regulation module is electrically connected to the electric precision flow distribution valve and the mass flow controller to be calibrated, respectively. It is used to control the electric precision flow distribution valve to perform independent pre-calibration, and based on the pre-calibration results, to coordinately control the flow of each branch to achieve batch synchronous calibration of the mass flow controller to be calibrated.

[0007] The digital monitoring and testing module includes multiple digital flow detection units connected to the output terminals of each mass flow controller to be calibrated, which are used to collect the actual output flow data of each controller in real time and transmit it to the central core control and adjustment module.

[0008] The safety protection module includes pressure sensors and / or overload protection units installed at key nodes of pipelines at all levels, used to monitor system pressure and operating status, and to perform safety protection actions in case of abnormalities.

[0009] Furthermore, the central core control and adjustment module has a built-in fault diagnosis unit, which is electrically connected to the pressure detection component of the standard gas source interface, the status detection component of the electric precision flow distribution valve, the communication detection component of the digital detection unit, and the current detection component of the mass flow controller to be calibrated. The touch display unit is used to display the fault location, fault type, and troubleshooting suggestions. The central core control and adjustment module is equipped with an audible and visual alarm component and has the function of storing calibration data when a fault occurs.

[0010] Furthermore, based on the preset range of the calibration range, the number of calibration points is set to include the number of zero and full-scale points. The central core control and adjustment module imports gas type parameters and initialization parameters corresponding to the calibration range and the number of calibration points.

[0011] Furthermore, the standard flow detection unit of the primary main pipeline is a standard flow sensor, and the control signal of the electric precision flow distribution valve and the feedback signal of the standard flow sensor form a closed loop for the pre-calibration of the electric precision flow distribution valve.

[0012] Furthermore, the safety protection module also includes a safety valve installed in the primary main pipeline and / or the secondary branch pipeline, and the detection signal of the pressure sensor is input to the central core control and regulation module for linkage control of the precision pressure regulating valve.

[0013] Secondly, the present invention also provides a rapid calibration control device for a multi-stage multi-connected mass flow controller, including any one of the rapid calibration control systems for a multi-stage multi-connected mass flow controller, the device including a housing; the housing adopts a multi-layer layout structure, wherein the upper layer is equipped with the multi-stage diversion pipeline module, the middle layer is equipped with the central core control and adjustment module and the digital monitoring and testing module, and the lower layer is equipped with the safety protection module;

[0014] The outer casing integrates a standard gas source interface, a mass flow controller mounting interface, and a data interface. The standard gas source interface is connected to the multi-stage diversion pipeline module, the mass flow controller mounting interface is connected to the multi-stage diversion pipeline module, and the data interface is electrically connected to the central core control and regulation module.

[0015] Furthermore, the bottom of the outer casing is equipped with a support component that has both moving and fixing functions, and the device also integrates a wireless communication module for data interaction and remote monitoring with an external terminal.

[0016] Furthermore, each branch of the three-stage diversion pipeline is equipped with a pressure regulator, which is connected to the central core control and adjustment module.

[0017] Furthermore, it also includes a housing sealing unit, which includes a clean gas generator and a particulate matter sensor. The clean gas generator is connected to the internal space of the housing, and the particulate matter sensor is connected to the central core control and adjustment module.

[0018] Thirdly, the present invention also provides a rapid calibration control method for a multi-stage multi-connected mass flow controller, applicable to any of the rapid calibration control systems or devices described in any one of the claims, comprising the following steps:

[0019] With all downstream mass flow controllers to be calibrated closed, independently adjust the flow distribution valves of each branch in the secondary diversion pipeline, and establish the flow characteristic model of each valve based on the upstream standard flow.

[0020] Based on the pre-calibration model, the flow of each branch is controlled collaboratively, providing a stable calibration flow for multiple mass flow controllers to be calibrated simultaneously, and their output flow is collected for deviation calculation and correction.

[0021] The calibrated mass flow controllers are sampled and tested in groups. The calibration error of other controllers in the same group is estimated by using the sampled data and pipeline flow fluctuations, so as to determine the batch calibration results.

[0022] The present invention has the following beneficial effects:

[0023] Firstly, addressing the problem that existing calibration control systems struggle to meet the demands of batch and high-consistency calibration, this invention innovatively adopts a "valve pre-calibration – collaborative control – batch calibration" technical approach. The central core control and regulation module first independently calibrates the flow characteristics of multiple electric precision flow distribution valves in the secondary branch pipeline, establishing a precise flow-control command mapping model. This fundamentally solves the problem of uneven flow distribution and inconsistent calibration benchmarks caused by differences in the characteristics of flow distribution valves in each branch of a multi-path parallel calibration control system. Based on this pre-calibration model, the system can perform collaborative and precise control of multiple calibration branches, ensuring stable, accurate, and consistent input flow conditions for each mass flow controller to be calibrated. Combined with a high-resolution digital monitoring and testing module for real-time flow acquisition and deviation feedback, the central core control and regulation module can perform independent closed-loop correction for each controller, ultimately achieving high-precision, high-consistency synchronous batch calibration of multiple mass flow controllers, significantly improving calibration efficiency and the reliability of results.

[0024] Secondly, addressing the issues of low integration, complex operation, and poor field adaptability of existing calibration devices, this invention highly integrates the aforementioned calibration control system into a modular, structurally optimized chassis. The device's casing employs a multi-layered layout design, partitioning the piping module, control module, detection module, and safety protection module to ensure the neatness of the internal gas and electrical circuits, thereby improving reliability and maintenance convenience. By integrating standardized gas interfaces, controller interfaces, data interfaces, and safety control components, rapid deployment and connection of the device are achieved. Combined with built-in fault diagnosis, safety interlock protection (such as pressure monitoring and overload cutoff), and optional wireless communication functions, this device not only significantly simplifies the field calibration process and lowers the operational threshold for personnel, but also enhances adaptability and safety in various industrial environments, truly realizing the transformation from a precision laboratory device to a highly efficient and reliable field tool. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the rapid calibration control system for the multi-stage, multi-connected mass flow controller of the present invention;

[0027] Figure 2This is a structural diagram of the rapid calibration control device for the multi-stage, multi-connected mass flow controller of the present invention;

[0028] Figure 3 This diagram illustrates the working steps of the rapid calibration control method for the multi-stage, multi-connected mass flow controller of the present invention.

[0029] Attached diagram descriptions: 1. Multi-stage diversion pipeline module; 2. Central core control and regulation module; 3. Digital monitoring and testing module; 4. Safety protection module. Detailed Implementation

[0030] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, apparatus, product, or end that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or ends.

[0032] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0033] In existing technologies, the calibration process of mass flow controllers generally faces problems of low efficiency and insufficient accuracy. Traditional calibration equipment is limited by a single-channel architecture, which cannot meet the needs of mass production. While multi-channel calibration solutions can improve efficiency, uneven fluid distribution leads to poor consistency in calibration results. Full-range detection mode consumes a lot of resources, and manual analysis is inefficient and difficult to adapt to large-scale calibration scenarios. Some solutions attempt to optimize pipeline structure, but they do not solve the problems of valve control accuracy and batch error estimation, thus hindering the balance between calibration efficiency and cost.

[0034] To solve the above technical problems, refer to Figure 1This application provides a rapid calibration control system for a multi-stage, multi-connected mass flow controller, including a multi-stage branch pipeline module, a central core control and adjustment module, a digital monitoring and testing module, and a safety protection module;

[0035] The multi-stage distribution pipeline module 1 includes a primary main pipeline, a secondary distribution pipeline, and a tertiary distribution pipeline connected in series. The primary main pipeline is used to connect to a standard gas source and is equipped with a pressure stabilizing and standard flow detection unit. The secondary distribution pipeline has several independent branches, each equipped with a controllable electric precision flow distribution valve. The tertiary distribution pipeline includes multiple parallel branches, each with an interface for a mass flow controller to be calibrated.

[0036] The central core control and regulation module 2 is electrically connected to the electric precision flow distribution valve and the mass flow controller to be calibrated, respectively. It is used to control the electric precision flow distribution valve to perform independent pre-calibration and to coordinately control the flow of each branch based on the pre-calibration results to achieve batch synchronous calibration of the mass flow controller to be calibrated.

[0037] The digital monitoring and testing module 3 includes multiple digital flow detection units that are respectively connected to the output end of each mass flow controller to be calibrated, for real-time acquisition of the actual output flow data of each controller and transmission to the central core control and adjustment module.

[0038] Safety protection module 4 includes pressure sensors and / or overload protection units installed at key nodes of pipelines at all levels, used to monitor system pressure and operating status, and to perform safety protection actions in case of abnormalities.

[0039] It should be noted that, in some embodiments, the multi-stage branch pipeline module 1 constitutes the physical foundation of the system, comprising a primary main pipeline, a secondary branch pipeline, and a tertiary branch pipeline connected in series. The primary main pipeline is the gas source inlet, integrating a precision pressure regulating valve and a standard flow sensor. The former stabilizes the upstream gas source pressure at a preset constant value, while the latter accurately measures the total gas flow rate through the main pipeline. The secondary branch pipeline consists of several (e.g., 4, 8, etc.) parallel independent branches, each equipped with an electrically operated precision flow distribution valve that receives control signals and precisely adjusts the opening of its branch. Each secondary branch connects downstream to multiple (e.g., each secondary branch can connect to 4) tertiary branch pipelines, and each tertiary branch is equipped with a quick-connect interface for connecting to the mass flow controller (MFC) to be calibrated. This "one-to-many" tree-like pipeline structure forms the basis for batch calibration workstations. The central core control and regulation module is the heart of the entire system, typically consisting of an industrial-grade programmable logic controller (PLC), a human-machine interface touchscreen, and related control software. The PLC is connected to each electric precision flow distribution valve and the control terminal of each MFC to be calibrated via digital or analog signal cables. One of its core functions is to perform "pre-calibration" of the flow distribution valves: before calibration begins, all MFCs to be calibrated are closed, and a mathematical model of "control command - actual flow" for each valve is established by controlling the individual actions of each flow distribution valve in the secondary pipeline and combining feedback from the standard flow sensor in the primary main pipeline. Another core function is to coordinate the control of all valves in the secondary branches during formal calibration, based on this model, to simultaneously and accurately provide consistent flow conditions that meet the calibration point requirements to the input terminals of dozens or even hundreds of downstream MFCs to be calibrated. The digital monitoring and testing module is responsible for collecting the final output data. It contains multiple independent, high-precision digital flow meters, each connected to the output terminal of one MFC to be calibrated. These flow meters collect the actual gas flow rate after MFC regulation in real time and transmit the data to the central core control and regulation module in real time via a high-speed data acquisition card. The safety protection module includes safety relief valves and pressure sensors distributed at key nodes such as the main pipeline inlet and secondary branches, as well as overload protectors connected to the MFC power supply circuit. The pressure sensors monitor the pipeline pressure in real time, and once overpressure occurs, the signal is transmitted to the PLC to trigger an alarm or control the safety valve. The overload protection unit immediately cuts off the power supply to an MFC when it detects an abnormal current (usually indicating valve failure or flow control failure) to prevent damage.

[0040] Preferably, the central core control and adjustment module 2 has a built-in fault diagnosis unit. The fault diagnosis unit is electrically connected to the pressure detection component of the standard gas source interface, the status detection component of the electric precision flow distribution valve, the communication detection component of the digital detection unit, and the current detection component of the mass flow controller to be calibrated. The touch display unit is used to display the fault location, fault type, and troubleshooting suggestions. The central core control and adjustment module is equipped with an audible and visual alarm component and has the function of storing calibration data when a fault occurs.

[0041] In a preferred embodiment, the central core control and regulation module 2 also incorporates a dedicated fault diagnosis unit. This unit monitors multiple key signal points in the system in real time. For example, it monitors whether the pressure at the standard gas source inlet is within the normal range using a pressure sensor; it determines whether each electric precision flow distribution valve is stuck or damaged through valve feedback signals or current monitoring; it determines whether the data link with each digital flow meter is unobstructed through communication status monitoring; and it determines whether each MFC to be calibrated is working properly by monitoring its drive current. When the diagnostic module detects any abnormality, it immediately highlights the fault location on the touchscreen in a graphical interface (e.g., "MFC No. 3 current exceeds limit in secondary branch No. 2"), and displays a text description of the fault type and possible troubleshooting suggestions (e.g., "Check the wiring or replace the MFC"). Simultaneously, the system's audible and visual alarm will activate to alert the operator. Furthermore, the system automatically saves all calibration data, such as flow rate, pressure, and valve opening, at the moment the fault occurs, forming a fault snapshot for subsequent analysis.

[0042] Preferably, based on the preset range of the calibration range, the number of calibration points is set to include the number of zero and full-scale points, and the central core control and adjustment module imports gas type parameters and initialization parameters corresponding to the calibration range and the number of calibration points.

[0043] In a preferred embodiment, before actual operation, parameters need to be preset in the human-machine interface of the central core control and adjustment module according to the model and specifications of the MFC to be calibrated. The operator needs to select or input the gas type (e.g., nitrogen, argon), as different gases have different physical properties. Next, the calibration range needs to be set, for example, 0-500 sccm (standard milliliters per minute). Then, the number and distribution of calibration points need to be set. The number of calibration points is usually no less than 5, and must include the zero point and full-scale point (i.e., 0 sccm and 500 sccm). Intermediate points can be set proportionally or according to specific requirements, such as 10%, 30%, 50%, 70%, and 90% of the range. After these initialization parameters are loaded into the PLC, they will become the basis for subsequent automatic calibration processes (such as setting pre-calibration points, setting target flow rates, and error judgment thresholds), enabling the system to perform customized calibration for MFCs of different specifications.

[0044] Preferably, the standard flow detection unit of the primary main pipeline is a standard flow sensor, and the control signal of the electric precision flow distribution valve and the feedback signal of the standard flow sensor form a closed loop for the pre-calibration of the electric precision flow distribution valve.

[0045] It is important to note that establishing a high-precision closed-loop control system is crucial during the independent pre-calibration process of the flow distribution valve. In practice, the central core control module (PLC) sends an initial control command (such as a voltage signal) to a designated electric precision flow distribution valve. Changes in valve opening lead to changes in flow rate, which are reflected in the readings of the standard flow sensor flowing through the primary main pipeline. The PLC continuously reads the real-time measurement values ​​from the standard flow sensor and compares them with the target flow rate value at the current calibration point. If a deviation exists, the PLC adjusts the control command sent to the flow distribution valve in real time based on control algorithms such as PID control, until the standard flow sensor reading stabilizes within a very small permissible error range of the target value. The stable control command value at this point is recorded as the precise control parameter for the valve at the current flow rate. This "command-feedback-adjustment" closed-loop process is repeated at all preset calibration points of the valve, thereby establishing a high-precision flow characteristic model for the valve.

[0046] Preferably, the safety protection module further includes a safety valve installed in the primary main pipeline and / or the secondary branch pipeline, and the detection signal of the pressure sensor is input to the central core control and adjustment module for linkage control of the precision pressure regulating valve.

[0047] It should be noted that in some embodiments, in addition to installing safety valves at key pipeline nodes as a final physical pressure relief guarantee, the system also includes pressure sensors, for example, installed after the pressure regulating valves in each branch of the secondary diversion pipeline or the primary main pipeline. The signals from these pressure sensors are transmitted in real time to the central core control and regulation module. The central core control and regulation module sets safe upper and lower pressure limits. When the detected pressure value exceeds the safe upper limit, the PLC not only triggers an audible and visual alarm but also immediately outputs a control signal to actively close (or regulate) the precision pressure regulating valve at the front end of the primary main pipeline, and even close the upstream main gas supply solenoid valve, cutting off or reducing the gas supply at the source to achieve proactive pressure suppression, rather than simply providing post-event pressure relief. This "monitoring-control" linkage can more quickly and proactively prevent abnormal increases in system pressure, protecting pipelines and precision valves.

[0048] refer to Figure 2 The present invention also provides an embodiment of a rapid calibration control device for a multi-stage multi-connected mass flow controller, comprising any one of the rapid calibration control systems for a multi-stage multi-connected mass flow controller, wherein the device includes a housing; the housing has a multi-layer layout structure, wherein the upper layer is equipped with the multi-stage diversion pipeline module, the middle layer is equipped with the central core control and adjustment module and the digital monitoring and testing module, and the lower layer is equipped with the safety protection module;

[0049] The outer casing integrates a standard gas source interface, a mass flow controller mounting interface, and a data interface. The standard gas source interface is connected to the multi-stage diversion pipeline module, the mass flow controller mounting interface is connected to the multi-stage diversion pipeline module, and the data interface is electrically connected to the central core control and regulation module.

[0050] An integrated multi-stage, multi-connected mass flow controller rapid calibration control device, in some embodiments, houses the aforementioned calibration control system within a structured enclosure. This enclosure is typically a metal cabinet, with its internal space divided into three distinct physical layers: upper, middle, and lower. The upper layer is dedicated to installing the multi-stage branch pipeline module; all gas pipelines, valves, and connectors are neatly fixed to the mounting plate, with clear gas path routing for easy inspection and maintenance. The middle layer is the electrical control area, centrally housing the core control and regulation module (such as a PLC cabinet, industrial computer, power supply, etc.) and digital monitoring and testing modules (such as data acquisition card boxes, signal conditioners, etc.). The lower layer houses components of the safety protection module, such as the main power switch, overload protector, and exhaust guide pipes for safety valves. All external interfaces are integrated on the back or side of the casing: the standard gas source interface is connected to the upper primary main pipeline inlet via a pipe; multiple mass flow controller mounting interfaces (quick-plug connectors) are arranged on the panel, corresponding one-to-one with each branch of the upper three-level branch pipeline via internal pipes; data interfaces (such as Ethernet, USB, serial port, etc.) are electrically connected to the central core control and regulation module in the middle layer via cables for program download, data export and external communication.

[0051] Preferably, the bottom of the outer casing is equipped with a support component that has both moving and fixing functions, and the device also integrates a wireless communication module for data interaction and remote monitoring with an external terminal.

[0052] To facilitate the movement and fixation of the calibration device in different workplaces (such as different workstations on the production line, laboratories, and rework areas), the device is equipped with casters with brakes and height-adjustable support feet at its bottom. During movement, it can be easily pushed using the casters; once it reaches the designated position, the support feet can be lowered and tightened to stably support the device on the ground and prevent vibration during operation. In addition, the device integrates a wireless communication module (such as a Wi-Fi or 4G / 5G module), which connects to the communication port of the central core control and adjustment module. Through this module, the device can send real-time calibration progress, detection data for each MFC, and device operating status (pressure, temperature, alarm information, etc.) to a remote monitoring center or an engineer's mobile app. Simultaneously, the monitoring center can also send commands in reverse, such as starting / stopping calibration, modifying calibration parameters, and requesting data uploads, enabling remote monitoring and operation.

[0053] Preferably, each branch of the three-stage diversion pipeline is equipped with a pressure regulator, which is connected to the central core control and adjustment module.

[0054] It should be noted that in some embodiments, a precision pressure regulator (or back pressure valve) is added to each branch of the tertiary branch pipeline (i.e., before the inlet of each MFC to be calibrated). These pressure regulators are also controlled by the central core control and regulation module. During the formal calibration process, in addition to coordinating the control of the flow distribution valves in the secondary pipeline to set the total flow rate, the central core control and regulation module can also fine-tune these precision pressure regulators based on feedback from the miniature pressure sensors installed on the tertiary branches (or, due to structural simplification, based on pressure estimated by the theoretical model). For example, even if the secondary distribution valve is precisely controlled, slight differences in the flow resistance characteristics of each MFC may still result in slight differences in their inlet pressures. In this case, the central core control and regulation module can independently adjust the pressure regulators on each tertiary branch, ensuring that the pressure values ​​reaching the inlet of each MFC to be calibrated are highly consistent, thereby eliminating calibration errors caused by differences in inlet pressure and achieving higher-precision parallel calibration.

[0055] Furthermore, it also includes a housing sealing unit, which includes a clean gas generator and a particulate matter sensor. The clean gas generator is connected to the internal space of the housing, and the particulate matter sensor is connected to the central core control and adjustment module.

[0056] refer to Figure 3 The present invention also provides an embodiment of a rapid calibration control method for a multi-stage multi-connected mass flow controller, applicable to any of the rapid calibration control systems or devices described in any one of the claims, comprising the following steps:

[0057] S1. With all downstream mass flow controllers to be calibrated closed, independently adjust the flow distribution valves of each branch in the secondary diversion pipeline, and establish the flow characteristic model of each valve based on the upstream standard flow.

[0058] S2. Based on the pre-calibration model, the flow of each branch is controlled collaboratively to provide a stable calibration flow for multiple quality flow controllers to be calibrated at the same time, and the output flow of these controllers is collected for deviation calculation and correction.

[0059] S3. Perform group sampling tests on the calibrated mass flow controllers, and use the sampling data and pipeline flow fluctuations to estimate the calibration error of other controllers in the same group in order to determine the batch calibration results.

[0060] It should be noted that in this embodiment, the first stage is valve pre-calibration: at the beginning of the calibration operation, all MFCs to be calibrated are not connected or in the closed state. The central core control and regulation module (PLC) controls each electric precision flow distribution valve in the secondary shunt pipeline sequentially and independently. For each valve, the PLC sends a control signal to it and reads the actual flow value flowing through the main pipeline standard flowmeter at this time, and records the data pair of "control instruction - actual flow". This process is repeated at multiple preset flow points (such as zero point, 10%, 30%, 50%, 70%, 90%, 100% of the full scale), so as to establish an accurate flow characteristic calibration curve (i.e., model) for each valve and store it. The second stage is synchronous batch closed-loop calibration: connect multiple MFCs to be calibrated to the tertiary pipeline interface. The central core control and regulation module calculates the collaborative control instruction according to the target flow point set by the calibration program (such as 100 sccm), and combines the characteristic models established for each secondary valve in the first stage, and sends it to all secondary valves at the same time. This enables all tertiary branches (i.e., the inlets of all MFCs) to obtain a stable and highly consistent 100 sccm flow input at the same time. Then, turn on the control function of the MFC itself, and at the same time, through the downstream digital flow detection unit, read the actual output value of each MFC in real time. The central core control and regulation module compares the actual output value of each MFC with 100 sccm and calculates the percentage error. For MFCs with an error exceeding the allowable range (such as ±1%), the PLC will send a correction instruction to it through its communication interface (such as analog voltage or digital communication) to adjust its internal parameters to make its output approach the target value. This process is repeated until the error of all MFCs at the current point meets the standard. After that, the system automatically switches to the next flow point (such as 200 sccm) and repeats this process until the calibration of all preset points is completed. The third stage is sampling and estimation verification: after completing the full-point calibration of all MFCs, instead of performing a full-range re-inspection one by one, statistical methods are used for efficiency verification. Group all MFCs according to the secondary branches they are connected to. In each group, randomly select a certain proportion of samples (such as 20%). For these sample MFCs, perform a complete full-range high-precision detection again. Calculate the maximum deviation, average deviation and standard deviation of the deviation of these samples within the range. At the same time, the system will retrieve the flow fluctuation data of the corresponding secondary branch recorded during the calibration process. Combining the measured statistical data of the samples and the flow fluctuation data of the branch, through the preset error estimation formula, the calibration error range of the remaining MFCs not sampled in this group can be estimated. If the estimation result shows that the errors of all untested MFCs are also likely to be within the qualified range, it can be determined that all MFCs in this batch are calibrated qualified. This method greatly shortens the time of batch verification while ensuring the reliability of the conclusion.

[0061] The device embodiments described above are merely illustrative. The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical modules; that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0062] Finally, it should be noted that the multi-stage, multi-connected mass flow controller rapid calibration control system and device disclosed in the embodiments of the present invention are merely preferred embodiments of the present invention, and are only used to illustrate the technical solutions of the present invention, not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-stage multi-parallel mass flow controller fast calibration control system, characterized in that, The multi-stage shunt pipeline module, the central core control and adjustment module, the digital monitoring and testing module, and the safety protection module, The multi-stage shunt pipeline module comprises a first-stage main pipeline, a second-stage shunt pipeline and a third-stage shunt pipeline connected in series; the first-stage main pipeline is configured to connect a standard gas source and is provided with a pressure stabilizing and standard flow detection unit; the second-stage shunt pipeline is provided with a plurality of independent branches, each branch being provided with a controllable electric precise flow distribution valve; and the third-stage shunt pipeline comprises a plurality of parallel branches, each branch being provided with a to-be-calibrated mass flow controller interface; The central core control and adjustment module is electrically connected with the electric precise flow distribution valve and the to-be-calibrated mass flow controller, respectively, and is configured to control the electric precise flow distribution valve to perform independent pre-calibration and cooperatively control the flow of each branch based on the pre-calibration result, and to perform batch synchronous calibration on the to-be-calibrated mass flow controller; The digital monitoring and testing module comprises a plurality of digital flow detection units connected to the output ends of the to-be-calibrated mass flow controllers, respectively, and is configured to collect actual output flow data of each controller in real time and transmit the data to the central core control and adjustment module to provide data support for control and adjustment; The safety protection module comprises pressure sensors and / or overload protection units arranged at key nodes of the pipelines at different stages, and is configured to monitor system pressure and operating state and perform a safety protection action when an abnormality occurs.

2. The multi-stage multi-parallel mass flow controller fast calibration control system of claim 1, wherein, The central core control and adjustment module is provided with a fault diagnosis unit, the fault diagnosis unit is electrically connected with a pressure detection component of a standard gas source interface, a state detection component of an electric precise flow distribution valve, a communication detection component of a digital detection unit, and a current detection component of a to-be-calibrated mass flow controller, a touch display unit is configured to display a fault position, a fault type and troubleshooting suggestions, the central core control and adjustment module is provided with an audible and visual alarm component, and the central core control and adjustment module has a function of storing calibration data when a fault occurs.

3. The multi-stage multi-parallel mass flow controller fast calibration control system of claim 1, wherein, According to a preset interval range of a calibration range, the number of calibration points is set to include zero points and full-scale points, and the central core control and adjustment module is imported with initialization parameters corresponding to a gas type parameter, a calibration range and a number of calibration points.

4. The multi-stage multi-parallel mass flow controller fast calibration control system of claim 1, wherein, The standard flow detection unit of the first-stage main pipeline is a standard flow sensor, a control signal of the electric precise flow distribution valve and a feedback signal of the standard flow sensor constitute a closed loop, and the closed loop is used for pre-calibration of the electric precise flow distribution valve.

5. The multi-stage multi-parallel mass flow controller fast calibration control system of claim 1, wherein, The safety protection module further comprises a safety valve arranged in the first-stage main pipeline and / or the second-stage shunt pipeline, a detection signal of the pressure sensor is input to the central core control and adjustment module, and the safety valve is used for linkage control of a precise pressure stabilizing valve.

6. A multi-stage multi-parallel mass flow controller fast calibration control device, characterized in that, The device comprises a shell, a multi-layer layout structure is adopted inside the shell, an upper layer of the multi-layer layout structure is provided with the multi-stage shunt pipeline module, a middle layer of the multi-layer layout structure is provided with the central core control and adjustment module and the digital monitoring and testing module, and a lower layer of the multi-layer layout structure is provided with the safety protection module. The shell is integrated with a standard gas source interface, a mass flow controller installation interface and a data interface, the standard gas source interface is connected with the multi-stage shunt pipeline module, the mass flow controller installation interface is connected with the multi-stage shunt pipeline module, and the data interface is electrically connected with the central core control and adjustment module.

7. The multi-stage multi-parallel mass flow controller fast calibration control device according to claim 6, wherein, The bottom of the shell is provided with a support component with moving and fixing functions, and the device is further integrated with a wireless communication module for data interaction with an external terminal and remote monitoring.

8. The multi-stage multi-parallel mass flow controller fast calibration control device of claim 6, wherein, A pressure regulator is arranged on each branch of the three-stage shunt pipeline, and the pressure regulator is connected with the central core control and adjustment module.

9. The multi-stage multi-parallel mass flow controller fast calibration control device of claim 6, wherein, The shell sealing unit includes a clean gas generator and a particulate matter sensor, the clean gas generator is communicated with the internal space of the shell, and the particulate matter sensor is connected with the central core control and adjustment module.

10. A method for fast calibration control of a multi-stage multi-parallel mass flow controller, characterized in that, The application is applied to the multi-stage multi-connection mass flow controller rapid calibration control system of any one of claims 1-5 or the multi-stage multi-connection mass flow controller rapid calibration control device of any one of claims 6-9, and includes the following steps: In the state of closing all to-be-calibrated mass flow controllers downstream, the flow distribution valves of each branch of the secondary shunt pipeline are independently adjusted, and the flow characteristic model of each valve is established according to the upstream standard flow; Based on the pre-calibration model, the flow of each branch is controlled, stable calibration flow is provided for multiple to-be-calibrated mass flow controllers, and the output flow is collected for deviation calculation and correction; The calibrated mass flow controllers are grouped and sampled, the calibration errors of the remaining controllers in the same group are inferred by using the sampling data and the pipeline flow fluctuation, and the batch calibration result is determined.

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