Vehicle-mounted sonic nozzle method gas flow standard device

Abstract

The utility model discloses a vehicle-mounted sonic nozzle method gas flow standard device, which comprises a compartment body, a gas flow standard device, a gas flow standard device, a gas flow standard device and a gas flow standard device, wherein an installation chamber and a detection chamber are defined by the compartment body; the detected meter mounting module is arranged in the detection chamber; the standard verification module is arranged in the detection chamber, and the standard verification module is connected with the tested meter installation module; the power module is arranged in the mounting chamber, and the power module is constructed to exert a negative pressure suction effect on the standard verification module; and the control module is in signal connection with the power module and the standard verification module, and the control module is configured to adjust the detection range of the standard verification module and the suction pressure intensity of the power module. According to the vehicle-mounted sonic nozzle method gas flow standard device, all parts of the gas flow standard device are modularized, and maintenance and overhaul of the parts of the gas flow standard device are facilitated.

Description

Technical Field

[0001] This utility model relates to the field of gas flow meters, and in particular to a vehicle-mounted sonic nozzle method gas flow standard device. Background Technology

[0002] With the development of the national economy, industry and civil use have placed higher demands on the types, state parameters, flow range, and accuracy evaluation of gas flow measurement, and have also made the standard devices for calibrating flowmeters increasingly important. Currently, most standard devices are fixed in one location and cannot be moved. This shortcoming is very inconvenient for users with large flowmeters or those who need to complete instrument calibration in a timely manner.

[0003] Existing technologies use vehicle-mounted gas flow standard devices, which can be driven to the location of the user's instrument to quickly perform instrument calibration, making it convenient for the instrument user and eliminating intermediate steps such as transportation, waiting, loading and unloading of the instrument for calibration.

[0004] However, while existing vehicle-mounted gas flow standard devices can be directly accessed for calibration at the user's location, in order to improve space utilization, the power module of the gas flow standard device and the operation module for calibrating the gauge are located close together inside the vehicle. For ease of operation, the power module is generally located on the side away from the door. After prolonged use, the inspection and maintenance of the power module becomes inconvenient. Utility Model Content

[0005] This invention aims to solve at least one of the technical problems existing in the prior art. Therefore, one objective of this invention is to provide a vehicle-mounted sonic nozzle method gas flow standard device, which can make the inspection and maintenance of the power module more convenient.

[0006] An embodiment of this utility model proposes a vehicle-mounted sonic nozzle method gas flow standard device, comprising: a housing defining an installation chamber and a testing chamber; a test gauge mounting module disposed in the testing chamber; a standard calibration module disposed in the testing chamber, the standard calibration module being connected to the test gauge mounting module; a power module disposed in the installation chamber, the power module being configured to apply negative pressure suction to the standard calibration module; and a control module signal-connected to the power module and the standard calibration module, the control module being configured to adjust the testing range of the standard calibration module and the suction pressure of the power module.

[0007] This utility model discloses a vehicle-mounted sonic nozzle method gas flow standard device. The various parts of the gas flow standard device are modularized, which facilitates the maintenance and repair of the components. The power module is located in the installation chamber, while the measured instrument installation module and the standard calibration module are located in the testing chamber. Access to the installation chamber for maintenance and replacement of power module parts is more convenient. Separating the power module from the measured instrument installation module and the standard calibration module helps reduce the impact of power module operating noise on operators in the testing chamber.

[0008] In some embodiments, the installation room and the testing room are separated by a soundproofing device.

[0009] In some embodiments, an access panel is provided on at least one side wall of the installation chamber, and the access panel is provided with an access door.

[0010] In some embodiments, the test instrument mounting module includes an air inlet pipe, a test stand, a fixing pipe, and a filter. The air inlet pipe and the fixing pipe are disposed on both sides of the test stand. The fixing pipe is connected to the filter, and the filter is connected to the standard calibration module through a first connecting pipe.

[0011] According to some embodiments of the present invention, the meter installation module further includes: a meter connection device, wherein the air inlet pipe is disposed on the meter connection device, the meter connection device is configured to drive the air inlet pipe to move toward the meter on the meter mounting platform, so that the air inlet pipe and the fixed pipe are connected through the meter, and the meter connection device is signal connected to the control module.

[0012] According to some embodiments of the present invention, the meter-under-test connection device includes a clamping end, the air inlet pipe is disposed at the clamping end, and the meter-under-test connection device is configured to drive the clamping end to move axially along the air inlet pipe.

[0013] In some embodiments, the standard calibration module includes a stagnation container, a back pressure container, multiple sets of airflow channels with sonic nozzles, and switching valves corresponding to the airflow channels. The two ends of the multiple sets of airflow channels are respectively connected to the stagnation container and the back pressure container. The switching valves are all disposed in the back pressure container and correspond to the airflow channels. The stagnation container is connected to the filter of the test instrument mounting module through a first connecting pipe, and the back pressure container is connected to the power module through a second connecting pipe.

[0014] In some embodiments, the power module includes a suction device and an air compressor. The suction device is connected to the back pressure container of the standard calibration module via a second connecting pipe. The air compressor is adapted to supply air to the switching valve of the standard calibration module and the telescopic device of the test instrument mounting module.

[0015] According to some embodiments of the present invention, the power module further includes a support frame, wherein the suction device and the air compressor are both fixedly mounted on the support frame, and the support frame is detachably disposed in the installation chamber.

[0016] According to some embodiments of the present invention, a fan is provided on the support frame, and the fan faces the suction device and the air compressor.

[0017] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0019] Figure 1 This is one of the internal structural schematic diagrams of the gas flow standard device according to an embodiment of this utility model;

[0020] Figure 2 This is the second schematic diagram of the internal structure of the gas flow standard device according to an embodiment of this utility model;

[0021] Figure 3 This is a schematic diagram of the gas flow rate standard device according to an embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the structure of the meter mounting module according to an embodiment of this utility model;

[0023] Figure 5 This is a schematic diagram of the structure of the standard verification module according to an embodiment of the present invention;

[0024] Figure 6 This is a schematic diagram of the power module in an embodiment of the present invention.

[0025] Figure label:

[0026] 100 - Gas flow rate standard device;

[0027] 110 - Body; 111 - Installation compartment; 111a - Inspection port; 112 - Testing compartment;

[0028] 120 - Mounting module for the instrument under test; 121 - Air inlet pipe; 122 - Instrument stand; 123 - Fixing pipe; 124 - Filter; 125 - Connecting device for the instrument under test; 126 - Clamping end;

[0029] 130 - Standard verification module; 131 - Sonic nozzle; 132 - Airflow channel; 133 - Switch valve; 134 - Stagnation container; 135 - Back pressure container; 136 - Second connecting pipe;

[0030] 140 - Power module; 141 - Suction device; 142 - Air compressor; 143 - Support frame; 144 - Fan;

[0031] 150 - Control Module;

[0032] 160 - Sound insulation device;

[0033] 170 - Imports and exports. Detailed Implementation

[0034] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0035] Existing vehicle-mounted gas flow standard devices have power modules located on the side far from the vehicle door, making inspection and maintenance of the power modules inconvenient after prolonged use.

[0036] In view of this, the present invention provides a vehicle-mounted sonic nozzle method gas flow standard device, which can make the inspection and maintenance of the power module more convenient.

[0037] The following is for reference. Figures 1 to 6 This invention describes a vehicle-mounted sonic nozzle method gas flow standard device 100 according to an embodiment of the present invention. The gas flow standard device 100 can be used to calibrate gas flow meters such as turbine flow meters, ultrasonic flow meters, mass flow meters (such as Coriolis flow meters), and differential pressure flow meters. It can also be used to calibrate flow sensors in various industrial applications, as well as various types of gas meters and other equipment for commercial and residential use.

[0038] refer to Figure 1 , Figure 2 and Figure 3 The gas flow standard device 100 may include: a chamber 110, a meter installation module 120, a standard calibration module 130, a power module 140, and a control module 150.

[0039] The enclosure 110 defines the installation chamber 111 and the testing chamber 112. The meter under test installation module 120 is located in the testing chamber 112, and the meter under test can be connected to the gas flow standard device 100 for calibration through the meter under test installation module 120.

[0040] The standard verification module 130 is located in the testing chamber 112. The standard verification module 130 is connected to the meter installation module 120 and is used to verify the standard range of the meter.

[0041] The power module 140 is located in the installation chamber 111. The power module 140 is configured to apply negative pressure to the standard verification module 130, so that gas flows from the meter installation module 120, on which the meter is installed, through the standard verification module 130 to the power module 140, thus completing the verification of the meter.

[0042] The control module 150 is signal-connected to the power module 140 and the standard verification module 130. The control module 150 may include a human-machine interface, a control unit, and a detection unit. The detection unit is used to detect the critical conditions (pressure and temperature, etc.) upstream of the standard verification module 130. The operator inputs the corresponding parameters from the human-machine interface. The control unit controls the opening and closing states of the various switching valves 133 of the standard verification module 130 and the suction pressure of the power module 140 to control the gas flow rate through the standard verification module 130 during the verification process, so that the gas flow rate through the standard verification module 130 corresponds to the range of the meter being measured.

[0043] This utility model discloses a vehicle-mounted sonic nozzle method gas flow standard device 100. The various parts of the gas flow standard device 100 are modularized, which facilitates the maintenance and repair of the components. The power module 140 is located in the installation chamber 111, while the measured instrument installation module 120 and the standard calibration module 130 are located in the testing chamber 112. This makes it more convenient to enter the installation chamber 111 for maintenance and replacement of power module 140 parts. Furthermore, separating the power module 140 from the measured instrument installation module 120 and the standard calibration module 130 helps reduce the impact of noise from the power module 140 during operation on the operators in the testing chamber 112.

[0044] refer to Figure 1 and Figure 2 In some embodiments, since the equipment in the power module 140 (such as the suction device 141 described below) generates considerable noise during operation, the installation chamber 111 and the testing chamber 112 can be separated by a sound insulation device 160. This improves the acoustic characteristics of the working environment within the testing chamber 112 and reduces the impact of noise on operators.

[0045] Optionally, the sound insulation device 160 may include an acoustic barrier made of porous materials such as foam, fabric-wrapped fiberglass, or mineral wool, which can effectively reduce echoes and noise transmission. Alternatively, the sound insulation device 160 may also include a sound barrier made of high-density material specifically designed to block and absorb noise.

[0046] In some embodiments, an access port 111a is provided on at least one side wall of the installation chamber 111. For example, the access port 111a may be provided on one side wall of the installation chamber 111, such as the side wall of the installation chamber 111 opposite to the testing chamber 112, or both side walls of the installation chamber 111 along the width direction of the compartment may be provided with access ports 111a. An access door is provided at the access port 111a to facilitate the entry and exit of operators into the installation chamber 111 for installation, maintenance, and repair of the power module 140.

[0047] Understandably, the side wall between the installation chamber 111 and the testing chamber 112 has a sound insulation device 160. In order to avoid damaging the sound insulation effect, the inspection port 111a is not located on the side wall between the installation chamber 111 and the testing chamber 112.

[0048] refer to Figure 1 and Figure 2 In some embodiments, the standard verification module 130 and the meter installation module 120 are arranged opposite each other along the width of the testing chamber 112, defining an operating space between them. Operators can install and replace the meter within this operating space to perform verification operations, making the operation convenient. This also helps to distribute the weight of the gas flow standard device 100 reasonably within the carriage, thereby improving the stability of the carriage during hoisting and transportation and preventing damage to the gas flow standard device 100 during transport.

[0049] The testing chamber 112 is defined by an entrance / exit 170 at one end along its length away from the installation chamber 111. The entrance / exit 170 is equipped with a door, through which operators can get on and off the carriage.

[0050] refer to Figure 4 In some embodiments, the meter mounting module 120 may include an air inlet pipe 121, a meter mounting platform 122, a fixing pipe 123, and a filter 124. The air inlet pipe 121 and the fixing pipe 123 are located on both sides of the meter mounting platform 122. The fixing pipe 123 is connected to the filter 124, which filters impurities in the intake air to prevent damage to the standard calibration module 130. The filter 124 and the standard calibration module 130 are connected via a first connecting pipe. Thus, the meter under test is placed on the meter mounting platform 122, with both ends connected to the air inlet pipe 121 and the fixing pipe 123 respectively, allowing the meter to be connected to the gas flow standard device 100 for testing, making operation convenient.

[0051] refer to Figure 4According to some embodiments of this utility model, the meter installation module 120 may further include a meter connection device 125. An air inlet pipe 121 is disposed on the meter connection device 125. The meter connection device 125 is used to move the air inlet pipe 121 toward the meter on the meter stand 122, so that one end of the air inlet pipe 121 is connected to the air inlet end of the meter, and the meter moves together, so that the air outlet end of the meter is connected to the fixed pipe 123. In this way, the air inlet pipe 121 and the fixed pipe 123 are connected through the meter. At this time, the air inlet pipe 121, the meter, the fixed pipe 123, the filter 124, the standard calibration module 130 and the suction device 141 of the power module 140 form the detection circuit of the gas flow standard device 100, thereby facilitating calibration testing.

[0052] The meter connection device 125 can be connected to the control module 150. The operator can control the meter connection device 125 through the control module 150 to drive the meter to be connected to the gas flow standard device 100. The structure is simple and easy to operate, which reduces the labor intensity of the operator in installing the meter.

[0053] According to some embodiments of this utility model, the meter connection device 125 may include a clamping end 126, and an air inlet pipe 121 is disposed at the clamping end 126. The meter connection device 125 is configured to drive the clamping end 126 to move axially along the air inlet pipe 121. Exemplarily, the meter connection device 125 may be an electric telescopic device, such as an electric telescopic rod or an electric lead screw, or a pneumatic telescopic device, such as a cylinder. The clamping end 126 may be a clamp, and the clamping end 126 may be disposed at the telescopic end of the telescopic device. The extension and retraction of the meter connection device 125 drives the air inlet pipe 121 to move, so as to connect the meter to be tested into the detection circuit of the gas flow standard device 100, or to remove the calibrated meter from the gas flow standard device 100 and replace it with a new meter for testing. This makes the installation and replacement operation of the meter more mechanized and reduces the difficulty of operation for operators.

[0054] refer to Figure 5 In some embodiments, the standard verification module 130 may include a stagnation container 134 and a back pressure container 135, multiple sets of airflow channels 132 with sonic nozzles 131, and switching valves 133 corresponding to each airflow channel 132. The two ends of the multiple sets of airflow channels 132 are respectively connected to the stagnation container 134 and the back pressure container 135. The switching valves 133 are all located in the back pressure container 135 and correspond to the airflow channels 132. They are used to control the conduction state of different airflow channels 132. For example, when the switching valve 133 corresponding to an airflow channel 132 is closed, that airflow channel 132 is closed; when the switching valve 133 corresponding to an airflow channel 132 is open, that airflow channel 132 is connected to the back pressure container 135.

[0055] Multiple airflow channels 132 are connected to the meter-under-test (TMT) mounting module 120. When calibrating TMTs with different ranges, the control module 150 controls the opening and closing states of the switching valves 133 within different airflow channels 132, ensuring that different airflow channels 132 of the standard calibration module 130 are connected to the TMT mounting module 120 and correspond to the ranges of the TMTs. For example, the switching valve 133 can be an electrically controlled valve, controlled by an electrical signal to close or open the airflow channel 132. Alternatively, the switching valve 133 can also be a pneumatic valve, pneumatically extending or retracting to block or open the airflow channel 132.

[0056] Understandably, the principle behind calibrating and verifying the accuracy of a test instrument using the sonic nozzle method is as follows: when the airflow passing through the sonic nozzle 131 reaches the speed of sound (under critical conditions), pressure changes downstream of the sonic nozzle 131 will not affect the flow rate. Therefore, by controlling the pressure and temperature conditions upstream of the sonic nozzle 131 and accurately controlling the flow rate of the gas flow standard device 100, and comparing it with the reading of the test instrument, the test instrument can be calibrated. Compared to the conventional method of using a standard meter to calibrate the test instrument, this embodiment uses the sonic nozzle 131, which allows for the calibration of a wider range of test instruments. Furthermore, while the standard meter typically has a lifespan of one year, calibration using the sonic nozzle 131 extends its lifespan, thus saving equipment costs.

[0057] The stagnation container 134 is located at the upstream end of the airflow channel 132. As a relatively large container, the stagnation container 134 facilitates a uniform pressure distribution of the gas entering it and reduces gas turbulence, resulting in more stable gas flow and improved accuracy of the calibration results. The back pressure container 135 is located downstream of the airflow channel 132. It provides the necessary back pressure to maintain the critical conditions of the sonic nozzle 131 in the airflow channel 132, ensuring the accuracy of the calibration results. The back pressure container 135 also absorbs and attenuates pressure fluctuations within the pipeline caused by downstream equipment, reducing inaccuracies in calibration results due to downstream pressure fluctuations. The stagnation container 134 is connected to the filter 124 of the meter under test mounting module 120 via a first connecting pipe, and the back pressure container 135 is connected to the power module 140 via a second connecting pipe 136. This allows the meter under test mounting module 120, the standard calibration module 130, and the power module 140 to form a detection loop, facilitating the connection of the meter under test to the detection loop for calibration.

[0058] refer to Figure 6In some embodiments, the power module 140 may include a suction device 141 (e.g., a vacuum pump) and an air compressor 142. The suction device 141 is connected to the back pressure container 135 of the standard calibration module 130 via a second connecting pipe 136. That is, the suction device 141 is connected to the detection circuit of the gas flow standard device 100. When the suction device 141 is activated, the external airflow passes through the inlet pipe 121, the meter under test, the fixed pipe 123, the filter 124, the stagnation container 134, the airflow channel 132, and the back pressure container 135, and then flows out from the outlet of the suction device 141. The structure is simple and the operation is convenient. In this embodiment, both the switch valve 133 and the meter under test connection device 125 can be pneumatic devices. The air compressor 142 can be connected to the switch valve 133 and the meter under test connection device 125 via pipelines. The control module 150 controls the air supply of the air compressor 142, thereby controlling the opening and closing state of the switch valve 133 and the operation process of the meter under test connection device 125.

[0059] Thus, by controlling the movement of the meter connection device 125 through the air compressor 142, the meter can be connected to or disconnected from the detection circuit, reducing the labor intensity of the operator.

[0060] Understandably, in order to facilitate the connection between the back pressure container 135 and the suction device 141, the sound insulation device 160 may have a through hole to allow the second connecting pipe 136 to pass through. The outer wall of the second connecting pipe 136 and the inner wall of the through hole can be filled with sound insulation cotton to reduce the impact of the through hole on the sound insulation effect of the sound insulation device 160.

[0061] According to some embodiments of this utility model, the power module 140 may further include a support frame 143, on which the suction device 141 and the air compressor 142 are fixedly mounted. This improves the integration effect of the power module 140 and facilitates the inspection and maintenance of the suction device 141 and the air compressor 142. The support frame 143 is detachably disposed in the mounting chamber 111. For example, the support frame 143 may be provided with a locking block, and the mounting chamber 111 has a slot extending toward the inspection port 111a. The support frame 143 can be locked in the slot by the locking block. Of course, the support frame 143 may also be provided with multiple first fixing holes, and the mounting chamber 111 has second fixing holes corresponding to the first fixing holes. By connecting the first fixing holes and the second fixing holes, the support frame 143 can be detachably disposed in the mounting chamber 111.

[0062] According to some embodiments of this utility model, a fan 144 may also be provided on the support frame 143, with the fan 144 facing the suction device 141 and the air compressor 142. When the suction device 141 and the air compressor 142 are running, the fan 144 can deliver air to the suction device 141 and the air compressor 142 to cool them down, thereby enabling the suction device 141 and the air compressor 142 to operate within a safe temperature range and improving the service life of the equipment.

[0063] The working principle of the gas flow standard device 100 of this utility model:

[0064] The gas flow standard device 100 is transported by vehicle to the location of the meter under test. The meter under test is placed on the meter mounting platform 122. The meter under test connection device 125 is activated, which moves the air inlet pipe 121 toward the meter under test, connecting the meter under test into the detection circuit of the gas flow standard device 100. According to the range of the meter under test, the control module 150 controls the opening of the corresponding switch valve 133. The suction device 141 is activated, and after the airflow through the sonic nozzle 131 reaches the critical condition, the accuracy of the meter under test measurement result is verified. After the verification is completed, the meter under test connection device 125 drives the air inlet pipe 121 to reset, and the meter under test is removed from the detection circuit.

[0065] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0066] In the description of this utility model, "first feature" and "second feature" may include one or more of the features.

[0067] In the description of this utility model, "multiple" means two or more.

[0068] In the description of this utility model, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or it may include the first and second features not being in direct contact but being in contact through another feature between them.

[0069] In the description of this utility model, the terms "above", "over" and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0070] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0071] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A vehicle-mounted sonic nozzle method gas flow standard device (100), characterized in that, include: The compartment (110) defines the installation room (111) and the testing room (112); The test instrument is installed in module (120) in the test chamber (112); A standard verification module (130) is located in the testing chamber (112), and the standard verification module (130) is connected to the test instrument installation module (120); A power module (140) is provided in the installation chamber (111), and the power module (140) is configured to apply a negative pressure suction action to the standard verification module (130); A control module (150) is signal-connected to the power module (140) and the standard verification module (130). The control module (150) is configured to adjust the detection range of the standard verification module (130) and the suction pressure of the power module (140).

2. The vehicle-mounted sonic nozzle gas flow standard device (100) according to claim 1, characterized in that, The installation chamber (111) and the testing chamber (112) are separated by a soundproofing device (160).

3. The vehicle-mounted sonic nozzle gas flow standard device (100) according to claim 1, characterized in that, An inspection port (111a) is provided on at least one side wall of the installation chamber (111), and the inspection port (111a) is provided with an inspection door.

4. The vehicle-mounted sonic nozzle gas flow standard device (100) according to claim 1, characterized in that, The test instrument installation module (120) includes an air inlet pipe (121), a test instrument stand (122), a fixing pipe (123), and a filter (124). The air inlet pipe (121) and the fixing pipe (123) are located on both sides of the test instrument stand (122). The fixing pipe (123) is connected to the filter (124). The filter (124) is connected to the standard calibration module (130) through a first connecting pipe.

5. The vehicle-mounted sonic nozzle gas flow standard device (100) according to claim 4, characterized in that, The meter mounting module (120) further includes a meter connection device (125), wherein the air inlet pipe (121) is disposed on the meter connection device (125), and the meter connection device (125) is configured to drive the air inlet pipe (121) to move toward the meter on the meter mounting platform (122), so that the air inlet pipe (121) and the fixed pipe (123) are connected through the meter. The meter under test connection device (125) is connected to the control module (150) via signal.

6. The vehicle-mounted sonic nozzle gas flow standard device (100) according to claim 5, characterized in that, The meter connection device (125) includes a clamping end (126), the air inlet pipe (121) is disposed on the clamping end (126), and the meter connection device (125) is configured to drive the clamping end (126) to move along the axial direction of the air inlet pipe (121).

7. The vehicle-mounted sonic nozzle gas flow standard device (100) according to claim 1, characterized in that, The standard verification module (130) includes a stagnation container (134), a back pressure container (135), multiple sets of airflow channels (132) with sonic nozzles (131), and switching valves (133) corresponding to the airflow channels (132). The two ends of the multiple sets of airflow channels (132) are respectively connected to the stagnation container (134) and the back pressure container (135). The switching valves (133) are all located in the back pressure container (135) and correspond to the airflow channel (132). The stagnation container (134) is connected to the filter (124) of the meter installation module (120) via a first connecting pipe, and the back pressure container (135) is connected to the power module (140) via a second connecting pipe (136).

8. The vehicle-mounted sonic nozzle gas flow standard device (100) according to claim 1, characterized in that, The power module (140) includes a suction device (141) and an air compressor (142). The suction device (141) is connected to the back pressure container (135) of the standard calibration module (130) via a second connecting pipe (136). The air compressor (142) is adapted to supply air to the switching valve (133) of the standard calibration module (130) and the telescopic device of the test instrument mounting module (120).

9. The vehicle-mounted sonic nozzle gas flow standard device (100) according to claim 8, characterized in that, The power module (140) further includes a support frame (143), the suction device (141) and the air compressor (142) are both fixedly installed on the support frame (143), and the support frame (143) is detachably located in the installation chamber (111).

10. The vehicle-mounted sonic nozzle gas flow standard device (100) according to claim 9, characterized in that, A fan (144) is provided on the support frame (143), and the fan (144) faces the suction device (141) and the air compressor (142).

Images