Gas flow control and measurement device

Abstract

The invention discloses a gas flow control and measurement device, and relates to the field of fluid flow measurement, the gas flow control and measurement device comprises a shell and a laminar flow assembly, the laminar flow assembly comprises a laminar flow cavity seat and a laminar flow structure, and the laminar flow structure is internally provided with a laminar flow channel extending left and right; an air inlet hole and an air outlet hole which extend up and down and communicate with the laminar flow channel are formed in the left side and the right side of the laminar flow structure correspondingly, an air inlet channel and an air outlet channel are formed in the laminar flow cavity base, and each of the air inlet channel and the air outlet channel comprises a horizontal section communicating with the outside and a vertical section communicating with the horizontal section. The two ends of the laminar flow channels are arranged above a gas inlet channel and a gas outlet channel respectively and stacked in order, turbulent or torrent gas in the pipeline enters the inner wall of the impact vertical section from the horizontal section and then rises to flow into the laminar flow channels formed in the layers, direct impact of gas flow on the laminar flow structure is avoided, treatment of the laminar flow state of the gas is achieved, and the laminar flow state of the gas is guaranteed. And the pressure of each layer of flow channel is kept balanced and consistent, and the laminar flow effect of the gas is improved.

Description

Technical Field

[0001] The invention relates to the field of fluid flow control and measurement, and in particular to a device for controlling and measuring gas flow. Background Art

[0002] Flow controllers and flow meters with different ranges are needed in the fields of industrial control, semiconductors, environmental monitoring, etc. Common flow controllers and flow meters include: differential pressure flow controller, thermal (temperature difference) flow controller, float flow meter, rotor flow meter, differential pressure flow meter and thermal (temperature difference) flow meter.

[0003] According to the Hagen-Poiseuille law, when a Newtonian fluid flows through a pipe, when parameters such as temperature and pipe diameter are constant, if the fluid in the pipe is in a laminar state, the flow rate is proportional to the pressure. The laminar flow meter is a special differential pressure flow meter. The laminar flow meter is designed based on the Hagen-Poiseuille law and is a measuring tool for accurately measuring fluid flow.

[0004] Publication number CN214407616U discloses a laminar flow meter, including a fluid detection module and a measurement and calculation module placed outside the fluid detection module; the fluid detection module includes a shell, a laminar fluid matched with the shell, and the laminar fluid includes a plurality of overlapping and stacked laminar flow units; the laminar flow unit includes an upper laminar flow sheet, a lower laminar flow sheet and a laminar flow frame, the upper laminar flow sheet and the lower laminar flow sheet are overlapped and stacked, and laminar flow frames are respectively arranged on both sides between the upper laminar flow sheet and the lower laminar flow sheet, and the upper laminar flow sheet, the lower laminar flow sheet and the two laminar flow frames constitute a flow channel through which the fluid passes.

[0005] In the prior art, the fluid is discharged directly from the feed port through the laminar flow unit, and the fluid passes through the multi-layer flow channels irregularly. The middle flow channel corresponding to the feed port quickly rushes into the laminar flow channel due to the impact force of the fluid, resulting in different pressure values ​​at the upper and lower ends and the middle of the laminar flow unit, thereby affecting the detection accuracy of the detection pressure sensor, and further reducing the accuracy of flow control and measurement. Summary of the invention

[0006] In order to overcome the above defects of the prior art, the present invention provides a device for measuring gas flow to solve the problems existing in the above background technology.

[0007] The present invention provides the following technical solution: a device for controlling gas flow, comprising:

[0008] case;

[0009] A PCB board assembly is arranged inside the housing;

[0010] Sensor components, including temperature sensors, differential pressure sensors, and absolute pressure sensors;

[0011] A laminar flow component is arranged on the shell, including a laminar flow chamber seat and a laminar flow structure arranged on the top of the laminar flow chamber seat, a laminar flow channel extending left and right is arranged in the laminar flow structure, an air inlet and an air outlet extending up and down and connected to the laminar flow channel are respectively arranged on the left and right sides of the laminar flow structure, an air inlet channel and an air outlet channel are arranged on the laminar flow chamber seat, and the air inlet channel and the air outlet channel both include a horizontal section connected to the outside and a vertical section connected to the horizontal section, the vertical section of the air inlet channel is connected to the air inlet, and the vertical section of the air outlet channel is connected to the air outlet;

[0012] The laminar flow structure is also provided with pressure measuring holes, which are respectively connected to a differential pressure sensor and an absolute pressure sensor, and a temperature sensor is connected to an air inlet of the laminar flow structure.

[0013] The proportional valve assembly is connected to the air outlet passage of the laminar flow chamber seat and is used to adjust the flow in the pipeline.

[0014] Beneficial effects: The two ends of the laminar flow channel are respectively arranged above the gas inlet channel and the gas outlet channel, and are stacked in order. The turbulent or turbulent gas in the pipeline enters from the horizontal section to impact the inner wall of the vertical section, and then rises and flows into each layer to form a laminar flow channel, avoiding the direct impact of the airflow on the laminar structure. It not only realizes the processing of the gas laminar flow state, but also improves the gas laminar flow effect, so that the pressure of each layer of the flow channel remains balanced and consistent, thereby improving the detection accuracy of the pressure sensor, and then improving the accuracy of flow control and measurement.

[0015] Preferably, the laminar flow structure includes laminar flow spacers, laminar flow grooves, and pressure plates. The laminar flow spacers and laminar flow grooves are multi-layer structures and are staggered and stacked so that two laminar flow spacers are closely spaced by a laminar flow groove and form a laminar flow channel. The pressure plate is placed on a laminar flow groove at the top.

[0016] Preferably, the pressure measuring holes include two differential pressure detection holes and one absolute pressure detection hole. Differential pressure detection holes are provided at both ends of the laminar flow spacer and the pressure sampling plate. An absolute pressure detection hole is also provided in the middle of the pressure sampling plate. The differential pressure detection holes at both ends are commonly connected to the detection end of the differential pressure sensor for detecting the pressure difference value at both ends of the laminar flow structure, and the absolute pressure detection hole is connected to the absolute pressure sensor for detecting the absolute pressure value of the laminar flow structure.

[0017] Preferably, it also includes a laminar flow chamber sealing pressure plate, on which holes for assembling temperature sensors, differential pressure sensors and absolute pressure sensors are opened, so that the detection ends of the differential pressure sensor and the absolute pressure sensor are inserted into the holes of the laminar flow chamber sealing pressure plate and are connected and cooperated with the differential pressure detection hole and the absolute pressure detection hole respectively, and the detection end of the temperature sensor passes through the laminar flow chamber sealing pressure plate to be connected with the air intake channel.

[0018] Through the above-mentioned technical means, three pressure measuring points are set on the laminar flow structure, and the three pressure measuring points are respectively located at the two ends and the middle position of the laminar flow component, so that the differential pressure sensor measures the air pressure values ​​of the air inlet channel and the air outlet channel, and the flow data is obtained according to the measurement of the differential pressure sensor. During the gas transportation process, the absolute pressure sensor measures the absolute pressure value of the gas in the middle of the laminar flow component in real time. At the same time, a temperature sensor is configured at the air inlet to measure the real-time temperature of the airflow, and the absolute pressure value and temperature value are fed back to the host computer for real-time debugging, so as to realize pressure and temperature data compensation, so that the actual output flow rate is equal to the set flow rate, which greatly improves the precise control output of the airflow rate.

[0019] Preferably, a sealing sheet is placed at the bottom of the laminar flow chamber sealing pressure plate, and the sealing sheet is placed and fastened to the laminar flow chamber seat by screws to seal the laminar flow component. The sealing sheet is provided with a first airflow channel, a second airflow channel and a third airflow channel. The first airflow channel and the second airflow channel are used to cooperate with the laminar flow chamber sealing pressure plate to seal the two differential pressure detection holes, and one end of the first airflow channel extends to one side of the second airflow channel, so that the two detection ends of a differential pressure sensor can synchronously detect the two differential pressure detection holes, and the third airflow channel is used to cooperate with the laminar flow chamber sealing pressure plate to seal the two absolute pressure detection holes, so that the absolute pressure sensor can monitor the air pressure in the middle of the laminar flow structure alone.

[0020] Preferably, the shell includes an upper cover and an outer shell, the outer shell is used to cover the PCB board assembly and the laminar flow assembly, and the upper cover is detachably mounted on the top of the outer shell.

[0021] Preferably, the PCB board assembly includes a PCB board, a power supply and input / output interface, and a PCB board bracket. The power supply and input / output interface are welded on the top of the PCB board and exposed from the outer shell. The PCB board is vertically assembled on the PCB board bracket. The PCB board is installed inside the shell through plastic pillars.

[0022] Preferably, the proportional valve assembly includes a proportional valve body, a proportional valve seat, and a sealing ring. The proportional valve body is vertically assembled on the proportional valve seat and sealed with a sealing ring. The proportional valve seat is threadedly installed at the air outlet. The airflow passing through the laminar flow cavity seat is introduced into the inlet of the proportional valve body. The flow rate passing through is adjusted by controlling the opening and closing size of the proportional valve body. The airflow is then exported from the proportional valve body outlet through the valve seat, thereby outputting a stable gas flow at the rear end.

[0023] Preferably, the laminar flow structure cooperates with the sensor component to obtain the absolute pressure value, differential pressure value, and temperature value of the laminar flow structure, establish a laminar flow structure model and a calibration model, and control the output flow and flow calibration through the opening and closing size and frequency of the proportional valve component.

[0024] A device for measuring gas flow, comprising:

[0025] case;

[0026] A PCB board assembly is arranged inside the housing;

[0027] Sensor components, including temperature sensors, differential pressure sensors, and absolute pressure sensors;

[0028] A laminar flow component is arranged on the shell, including a laminar flow chamber seat and a laminar flow structure arranged on the top of the laminar flow chamber seat, a laminar flow channel extending left and right is arranged in the laminar flow structure, an air inlet and an air outlet extending up and down and connected to the laminar flow channel are respectively arranged on the left and right sides of the laminar flow structure, an air inlet channel and an air outlet channel are arranged on the laminar flow chamber seat, and the air inlet channel and the air outlet channel both include a horizontal section connected to the outside and a vertical section connected to the horizontal section, the vertical section of the air inlet channel is connected to the air inlet, and the vertical section of the air outlet channel is connected to the air outlet;

[0029] The laminar flow structure is also provided with pressure measuring holes, which are respectively connected to the differential pressure sensor and the absolute pressure sensor, and the temperature sensor is connected to the air inlet hole of the laminar flow structure;

[0030] It also includes a human-machine interaction device and a power supply component, and the human-machine interaction device and the power supply component are connected to the PCB board component.

[0031] Through the above-mentioned technical means, based on the laminar differential pressure control structure, in conjunction with PCB board components, sensor components, laminar structure components, human-computer interaction equipment, and power supply components, a dynamic measurement model is established to realize the monitoring of gas flow in the pipeline, so that flow measurement and control use a common development platform with strong versatility, short development cycle, low cost, and easy expansion of equipment series. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0033] Figure 2 It is a schematic diagram of the cross-sectional structure of the present invention.

[0034] Figure 3 It is a schematic diagram of a partial explosion structure of the present invention.

[0035] Figure 4 It is a schematic diagram of the cross-sectional structure of the laminar flow component of the present invention.

[0036] Figure 5 It is a schematic diagram of the laminar flow structure of the present invention.

[0037] Figure 6 It is a schematic diagram of the structure of the laminar flow chamber sealing pressure plate of the present invention.

[0038] Figure 7 It is a schematic diagram of the sealing sheet structure of the present invention.

[0039] Figure 8This is a schematic diagram of the explosion structure of the laminar structure of Example 3 of the present invention.

[0040] Fig. 9 This is a schematic diagram of the explosion structure of the laminar structure of Example 4 of the present invention.

[0041] Fig.10 It is a schematic diagram of the structure of the PCB board assembly of the present invention.

[0042] Fig.11 It is a schematic structural diagram of the proportional valve assembly of the present invention.

[0043] Fig.12 It is a schematic diagram of the structure of the present invention under the measuring state.

[0044] The accompanying drawings are marked as follows:

[0045] 1. Shell; 11. Outer shell; 12. Upper cover;

[0046] 2. PCB board assembly; 21. PCB board; 22. Power supply and input / output interface; 23. PCB board bracket;

[0047] 3. Sensor assembly; 31. Temperature sensor; 32. Differential pressure sensor; 33. Absolute pressure sensor;

[0048] 4. Laminar flow assembly; 41. Laminar flow chamber seat; 42. Laminar flow structure; 421. Laminar flow channel; 422. Air inlet; 423. Air outlet; 424. Air outlet; 425. Absolute pressure detection hole; 426. Laminar flow spacer laminar flow slot; 427. Laminar flow slot; 428. Pressure plate; 4271. Large flow rectangular notch; 4272. Small flow strip notch;

[0049] 5. Proportional valve assembly; 51. Proportional valve seat; 52. Proportional valve body; 53. Sealing ring;

[0050] 6. Laminar flow chamber sealing plate; 61. Temperature hole; 62. Differential pressure hole; 63. Absolute pressure hole;

[0051] 7. Sealing sheet; 71. First air flow channel; 72. Second air flow channel; 73. Third air flow channel;

[0052] 8. Human-computer interaction equipment;

[0053] 9. Power supply components. DETAILED DESCRIPTION

[0054] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0055] Embodiment 1, a gas flow control device, such as Figure 1-11 As shown, it includes: a housing 1, a PCB board assembly 2, a sensor assembly 3, a laminar flow assembly 4, and a proportional valve assembly 5.

[0056] The sensor assembly 3 includes a temperature sensor 31, a differential pressure sensor 32 and an absolute pressure sensor 33. The differential pressure sensor 32 and the absolute pressure sensor 33 each use two detection ends, and each sensor is electrically connected to the host computer through the connected PCB board assembly 2 for transmitting data of each sensor.

[0057] The laminar flow component 4 is snap-fitted or screwed to the bottom of the housing 1 , and the laminar flow component 4 includes a laminar flow chamber seat 41 and a laminar flow structure 42 embedded in the top of the laminar flow chamber seat 41 .

[0058] A laminar flow channel 421 extending leftward and rightward is provided in the laminar flow structure 42 , and an air inlet 422 and an air outlet 423 extending up and down and communicating with the laminar flow channel 421 are respectively provided on the left and right sides of the laminar flow structure 42 .

[0059] An air inlet channel and an air outlet channel with a threaded structure are provided at both ends of the laminar flow chamber seat 41, wherein the air inlet channel and the air outlet channel both include a horizontal section connected to the outside and a vertical section connected to the horizontal section, the vertical section of the air inlet channel is connected to the air inlet hole 422, and the vertical section of the air outlet channel is connected to the air outlet hole 423.

[0060] The laminar flow structure 42 is also provided with pressure measuring holes, which are respectively connected to the differential pressure sensor 32 and the absolute pressure sensor 33 , and the temperature sensor 31 is connected to the air inlet 422 of the laminar flow structure 42 .

[0061] The air inlet and outlet positions of the laminar flow channel 421 are respectively arranged above the air inlet channel and the air outlet channel of the laminar flow chamber seat 41, and are stacked in order. The turbulent or turbulent gas in the pipeline enters from the horizontal section to impact the inner wall of the vertical section, and then rises and flows into each layer to form the laminar flow channel 421, avoiding the direct impact of the airflow on the laminar structure. It not only realizes the processing of the laminar flow state of the gas, but also makes the pressure of the flow channel of each layer remain balanced and consistent, thereby improving the gas laminar flow effect.

[0062] The laminar flow structure 42 includes a laminar flow spacer 426, a laminar flow groove 427, and a pressure plate 428. The laminar flow spacer 427 and the laminar flow groove 425 are a multi-layer structure and are staggered and stacked so that two laminar flow spacers 426 are closely spaced by a laminar flow groove 427 to form a laminar flow channel 421. The pressure plate 428 is placed on a laminar flow groove 427 at the top.

[0063] The pressure measuring holes include two differential pressure detection holes 424 and one absolute pressure detection hole 425. Differential pressure detection holes 424 are provided at both ends of the laminar spacer 426 and the pressure sampling plate 428. The differential pressure detection holes 424 at both ends are stacked and overlapped, and an absolute pressure detection hole 425 is provided in the middle of the pressure sampling plate 428. The two differential pressure detection holes 424 are commonly connected to the detection end of the differential pressure sensor 32 for detecting the pressure difference value at both ends of the laminar structure 42, and the absolute pressure detection hole 425 is connected to the absolute pressure sensor 33 for detecting the absolute pressure value of the laminar structure 42.

[0064] In this embodiment, it also includes a laminar flow chamber sealing plate 6, on which holes for assembling a temperature sensor 31, a differential pressure sensor 32 and an absolute pressure sensor 33 are opened, so that the detection ends of the differential pressure sensor 32 and the absolute pressure sensor 33 are inserted into the holes of the laminar flow chamber sealing plate 6 and are connected and cooperated with the differential pressure detection hole 424 and the absolute pressure detection hole 425 respectively, and the detection end of the temperature sensor 31 passes through the laminar flow chamber sealing plate 6 and is connected to the air intake channel.

[0065] Three pressure measuring points are arranged on the laminar flow structure 42, and the three pressure measuring points are respectively located at the two ends and the middle position of the laminar flow structure, so that the differential pressure sensor 32 measures the air pressure values ​​of the air inlet 422 and the air outlet 423, and the flow data is obtained according to the measurement of the differential pressure sensor 32. During the gas transportation process, the absolute pressure sensor 33 measures the absolute pressure value of the gas in the middle of the laminar flow component in real time. At the same time, a temperature sensor 31 is arranged in the air inlet channel to measure the real-time temperature of the airflow, and the absolute pressure value and the temperature value are fed back to the host computer for real-time debugging, so as to realize the data compensation of pressure and temperature, so that the actual output flow rate is equal to the set flow rate, thereby greatly improving the precise control output of the airflow rate.

[0066] In this embodiment, the thickness of the laminar flow slot 427 is half of the laminar flow spacer 426 , and the flow rate can be determined according to the number of stacked layers of the laminar flow spacer 426 and the laminar flow slot 427 .

[0067] In this embodiment, if Figure 1 As shown, the housing 1 includes an upper cover 12 and an outer shell 11 . The outer shell 11 is used to cover the PCB board assembly 2 and the laminar flow assembly 4 . The upper cover 12 is detachably mounted on the top of the outer shell 11 .

[0068] In this embodiment, if Fig.10 As shown, the PCB board assembly 2 is arranged inside the shell 1, and the PCB board assembly 2 includes a PCB board 21, a power supply and input-output interface 22, and a PCB board bracket 23. The power supply and input-output interface 22 is welded on the top of the PCB board 21 and exposed from the shell 11. The PCB board 21 is vertically assembled on the PCB board bracket 23, and the PCB board 21 is installed inside the shell 1 through a plastic pillar.

[0069] In this embodiment, if Fig.11As shown, the proportional valve assembly 5 includes a proportional valve body 52, a proportional valve seat 51, and a sealing ring 53. The proportional valve body 52 is vertically assembled on the proportional valve seat 51 and sealed with the sealing ring 53. The proportional valve seat 51 is threadedly installed in the gas outlet channel. The airflow passing through the laminar flow cavity seat 41 is introduced into the inlet of the proportional valve body 52. ​​The flow rate passing through is adjusted by controlling the opening and closing size of the proportional valve body 52. ​​The airflow is then exported from the outlet of the proportional valve body 52 through the valve seat, so that a stable gas flow rate is output at the rear end.

[0070] In this embodiment, if Figure 7 As shown, a sealing sheet 7 is placed at the bottom of the laminar flow chamber sealing plate 6, and is fastened to the laminar flow chamber seat 41 by screws to seal the laminar flow component 4. A first airflow channel 71, a second airflow channel 72 and a third airflow channel 73 are provided on the sealing sheet 7. The first airflow channel 71 and the second airflow channel 72 are used to cooperate with the laminar flow chamber sealing plate 6 to seal the two differential pressure detection holes 424, and one end of the first airflow channel 71 extends to one side of the second airflow channel 72, so that the two detection ends of a differential pressure sensor 32 can synchronously detect the two differential pressure detection holes 424, thereby reducing the use of the differential pressure sensor 32 and reducing the production cost. The third airflow channel 73 is used to cooperate with the laminar flow chamber sealing plate 6 to seal the two absolute pressure detection holes 425, so that the absolute pressure sensor 33 can detect the air pressure in the middle of the laminar flow structure 42 alone, thereby improving the detection accuracy.

[0071] The working principle of this embodiment:

[0072] The host computer inputs the set flow value, and sends the signal to the proportional valve component 5, which opens a certain amount of opening to allow the gas to pass through the pipeline. The signals collected by the laminar flow component 4 and the sensor component 3 are sent to the host computer, and the flow data is calculated based on the differential pressure. The data is compensated by the temperature value and the insulation value, so that the host computer repeatedly fine-tunes the opening and closing degree of the proportional valve component 5 according to the measured value, so that the actual output flow is equal to the set flow, so as to achieve the purpose of accurately controlling the flow output;

[0073] With the laminar flow component 4 as the core, human-computer interaction equipment 8 and power supply component 9 are added. The fluid with unknown flow rate enters the flow measurement device. The differential pressure, absolute pressure and temperature values ​​are obtained by the sensor through the laminar flow component, and the current flow value is calculated and output to the display unit to realize the flow detection.

[0074] In Example 2, an absolute pressure detection hole 425 corresponding to the absolute pressure detection hole on the pressure collecting plate 428 may be opened in the middle of the laminar flow spacer 426, so that the absolute pressure detection hole 425 on each layer of the laminar flow spacer 426 and the absolute pressure detection hole 425 on the pressure collecting plate 428 are stacked and overlapped, and the absolute pressure detection hole 425 runs through the entire laminar flow structure 42, so that the absolute pressure sensor detects the absolute pressure value of the multi-layer laminar flow channel 421.

[0075] Embodiment 3, as Figure 8As shown, when used in a large flow scenario, that is, the flow rate exceeds 3L / min, a rectangular slot 4271 is opened in the laminar flow trough 427, wherein the arrangement order from bottom to top is laminar spacer 426, laminar flow trough 427 with rectangular slot 4271, laminar spacer 426, laminar flow trough 427 with rectangular slot 4271…pressure plate 428, “laminar spacer 426, laminar flow trough 427 with rectangular slot 4271” is a unit, and different numbers of units are arranged for different flow rates.

[0076] Embodiment 4, as Fig. 9 As shown, when used in a small flow scenario, that is, the flow rate does not exceed 3L / min, a strip slot 4272 is opened in the laminar flow trough 427, and a strip slot 4272 is opened in the laminar flow trough 427, wherein the arrangement order from bottom to top is laminar spacer 426, laminar flow trough 427 with strip slot 4272, laminar spacer 426, laminar flow trough 427 with strip slot 4272…pressure plate 428, “laminar spacer 426, laminar flow trough 427 with strip slot rectangular slot 4272” is a unit, and different numbers of units are arranged for different flow rates.

[0077] Embodiment 5, as Figure 5 , 8 As shown, there are two laminar flow spacers 426 and two laminar flow grooves 427 , which are alternately stacked with the laminar flow spacers 426 as the bottom. The pressure plate 428 is set on a laminar flow groove 427 at the top, so that the laminar flow structure 42 forms four laminar flow channels 421 .

[0078] In Example 6, the number of laminar flow spacers 426 and laminar flow grooves 427 can be increased or decreased to form laminar flow channels 421 with different numbers of layers, and can be adaptively adjusted according to the use environment.

[0079] Embodiment 7, a device for measuring gas flow, such as Figure 1 , 12 As shown, it includes the same housing 1, PCB board assembly 2, sensor assembly 3, laminar flow assembly 4 as those in Example 1, and also includes a human-computer interaction device 8 and a power supply assembly 9.

[0080] The human-computer interaction device 8 and the power supply assembly 9 are connected to the PCB board assembly 2 to provide a separate power supply and operating system for the measuring device.

[0081] The sensor assembly 3 includes a temperature sensor 31 , a differential pressure sensor 32 , and an absolute pressure sensor 33 .

[0082] The laminar flow component 4 is arranged on the housing 1, and includes a laminar flow chamber seat 41 and a laminar flow structure 42 arranged on the top of the laminar flow chamber seat 41. The laminar flow structure 42 is used as a basic model, and the sensor component 3 is used to obtain the relevant parameters of the laminar flow structure 42 and the measured absolute pressure value, differential pressure value, and temperature value, and the output flow and flow calibration are controlled through the opening and closing size and frequency of the proportional valve component 5.

[0083] The fluid with unknown flow rate enters the flow measurement device, and the differential pressure, absolute pressure, and temperature values ​​are obtained by the sensor through the laminar flow structure 42, and the current flow value is calculated and output to the human-computer interaction device 8. Finally, for different flow ranges, the width and number of laminar flow channels are changed to better adapt to the flow state and accurately control the output flow and flow measurement.

[0084] The dynamic measurement model constructed with the laminar flow structure 42 obtains the volume flow value, substitutes the relevant pressure and temperature values ​​to obtain the mass flow value, and can output the conversion of volume flow, mass flow, pressure, temperature and other units and other commonly used gas reference values.

[0085] Based on the laminar differential pressure measurement structure, in conjunction with the PCB board assembly 2, the sensor assembly 3, the laminar structure assembly 4, and the human-computer interaction device 8, a dynamic measurement model is established, so that flow measurement and control use a common development platform with strong versatility, short development cycle, low cost, and easy expansion of equipment series.

[0086] Several points should be explained: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, which may refer to mechanical connection or electrical connection, or internal communication between two components, or direct connection. "upper", "lower", "left" and "right" are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may change;

[0087] The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiment. Any equivalent modifications or changes made by ordinary technicians in this field based on the contents disclosed by the present invention should be included in the protection scope recorded in the claims.

Claims

1. A gas flow control device, characterized in that: include: Housing (1); A PCB board assembly (2) is arranged inside the housing (1); A sensor assembly (3), comprising a temperature sensor (31), a differential pressure sensor (32) and an absolute pressure sensor (33); A laminar flow component (4) is arranged on the housing (1), comprising a laminar flow chamber seat (41) and a laminar flow structure (42) arranged on the top of the laminar flow chamber seat (41); a laminar flow channel (421) extending left and right is arranged in the laminar flow structure (42); an air inlet (422) and an air outlet (423) extending up and down and communicating with the laminar flow channel are respectively arranged on the left and right sides of the laminar flow structure (42); an air inlet channel and an air outlet channel are arranged on the laminar flow chamber seat (41); the air inlet channel and the air outlet channel both comprise a horizontal section communicating with the outside and a vertical section communicating with the horizontal section; the vertical section of the air inlet channel is communicated with the air inlet hole (422), and the vertical section of the air outlet channel is communicated with the air outlet hole (423); The laminar flow structure (42) is also provided with pressure measuring holes, which are respectively connected to the differential pressure sensor (32) and the absolute pressure sensor (33); the temperature sensor (31) is connected to the air inlet (422) of the laminar flow structure (42); The proportional valve assembly (5) is connected to the air outlet passage of the laminar flow chamber seat (41).

2. A gas flow control device according to claim 1, characterized in that: The laminar flow structure (42) includes a laminar flow spacer (426), a laminar flow groove (427), and a pressure plate (428). The laminar flow spacer (427) and the laminar flow groove (427) are a multi-layer structure and are staggered and stacked so that two laminar flow spacers (426) are closely spaced by a laminar flow groove (427) to form a laminar flow channel (421). The pressure plate (428) is placed on a laminar flow groove (427) at the top.

3. A gas flow control device according to claim 2, characterized in that: The pressure measuring holes include two differential pressure detection holes (424) and one absolute pressure detection hole (425); the laminar flow spacer (426) and the pressure collecting plate (428) are provided with differential pressure detection holes (424) at both ends; the middle of the pressure collecting plate (428) is also provided with an absolute pressure detection hole (425); the differential pressure detection holes (424) at both ends are connected to the detection end of the differential pressure sensor (32) for detecting the pressure difference value at both ends of the laminar flow structure (42); the absolute pressure detection hole (425) is connected to the absolute pressure sensor (33) for detecting the absolute pressure value of the laminar flow structure (42).

4. A gas flow control device according to claim 3, characterized in that: It also includes a laminar flow cavity sealing plate (6), on which holes for assembling a temperature sensor (31), a differential pressure sensor (32) and an absolute pressure sensor (33) are provided, so that the detection ends of the differential pressure sensor (32) and the absolute pressure sensor (33) are inserted into the holes of the laminar flow cavity sealing plate (6) and are respectively connected and matched with the differential pressure detection hole (424) and the absolute pressure detection hole (425), and the detection end of the temperature sensor (31) passes through the laminar flow cavity sealing plate (6) and is connected with the air intake channel.

5. A gas flow control device according to claim 4, characterized in that: A sealing sheet (7) is placed at the bottom of the laminar flow chamber sealing plate (6), and the sealing sheet (7) is fastened to the laminar flow chamber seat (41) by screws to seal the laminar flow component (4). The sealing sheet (7) is provided with a first airflow channel (71), a second airflow channel (72) and a third airflow channel (73). The first airflow channel (71) and the second airflow channel (72) are used to cooperate with the laminar flow chamber sealing plate (6) to seal the two differential pressure detection holes (424), and one end of the first airflow channel (71) extends to one side of the second airflow channel (72), so that the two detection ends of a differential pressure sensor (32) can synchronously detect the two differential pressure detection holes (424). The third airflow channel (73) is used to cooperate with the laminar flow chamber sealing plate (6) to seal the two absolute pressure detection holes (425), so that the absolute pressure sensor (33) can monitor the air pressure in the middle of the laminar flow structure (42) alone.

6. A gas flow control device according to claim 1, characterized in that: The housing (1) comprises an upper cover (12) and an outer shell (11); the outer shell (11) is used to cover the PCB board assembly (2) and the laminar flow assembly (4); and the upper cover (12) is detachably mounted on the top of the outer shell (11).

7. A gas flow control device according to claim 1, characterized in that: The PCB board assembly (2) comprises a PCB board (21), a power supply and input / output interface (22), and a PCB board bracket (23); the power supply and input / output interface (22) is welded on the top of the PCB board (21) and exposed from the housing (11); the PCB board (21) is vertically mounted on the PCB board bracket (23); and the PCB board (21) is mounted inside the housing (1) via a plastic support.

8. A gas flow control device according to claim 7, characterized in that: The proportional valve assembly (5) comprises a proportional valve body (52), a proportional valve seat (51), and a sealing ring (53). The proportional valve body (52) is vertically mounted on the proportional valve seat (51) and sealed by the sealing ring (53). The proportional valve seat (51) is threadedly mounted on the gas outlet. The airflow passing through the laminar flow cavity seat (41) is introduced into the inlet of the proportional valve body (52). The flow rate passing through is adjusted by controlling the opening and closing size of the proportional valve body (52). The airflow is then led out from the outlet of the proportional valve body (52) through the valve seat, so that a stable gas flow rate is output at the rear end.

9. A gas flow control device according to claim 1, characterized in that: The laminar flow structure (42) cooperates with the sensor component (3) to obtain the absolute pressure value, differential pressure value and temperature value of the laminar flow structure (42), establish a laminar flow structure model and a calibration model, and control the output flow and flow calibration through the opening and closing size and frequency of the proportional valve component (5).

10. A device for measuring gas flow, characterized in that: include: include: Housing (1); A PCB board assembly (2) is arranged inside the housing (1); A sensor assembly (3), comprising a temperature sensor (31), a differential pressure sensor (32) and an absolute pressure sensor (33); A laminar flow component (4) is arranged on the housing (1), comprising a laminar flow chamber seat (41) and a laminar flow structure (42) arranged on the top of the laminar flow chamber seat (41); a laminar flow channel (421) extending left and right is arranged in the laminar flow structure (42); an air inlet (422) and an air outlet (423) extending up and down and communicating with the laminar flow channel are respectively arranged on the left and right sides of the laminar flow structure (42); an air inlet channel and an air outlet channel are arranged on the laminar flow chamber seat (41); the air inlet channel and the air outlet channel both comprise a horizontal section communicating with the outside and a vertical section communicating with the horizontal section; the vertical section of the air inlet channel is communicated with the air inlet hole (422), and the vertical section of the air outlet channel is communicated with the air outlet hole (423); The laminar flow structure (42) is also provided with pressure measuring holes, which are respectively connected to the differential pressure sensor (32) and the absolute pressure sensor (33); the temperature sensor (31) is connected to the air inlet (422) of the laminar flow structure (42); It also includes a human-machine interaction device (8) and a power supply component (9), and the human-machine interaction device (8) and the power supply component (9) are connected to the PCB board component (2).

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