CN112945458B - Automatic testing system, method and device for pressure gauge - Google Patents

Abstract

The invention discloses an automatic testing system, method and device for a pressure gauge, and relates to the technical field of instrumentation testing. The system includes a rotating mechanism, a data acquisition mechanism and a data processing mechanism; the rotating mechanism is provided with a test equipment installation part, a linear guide, a slider and a piston, the piston includes a piston cavity and a piston rod, and the piston cavity is located in the test equipment installation part. Between the slider and the slider, when the slider moves on the linear guide, the piston rod moves, the gas pressure in the piston cavity changes and acts on the pressure gauge under test through the air pressure channel, and the measured pressure value is obtained through the pressure gauge under test; data acquisition The mechanism includes an atmospheric pressure sensor, an electronic temperature measurement structure and an electronic distance measurement structure. The data processing mechanism receives the information detected by the data acquisition mechanism and calculates the theoretical pressure value and compares it with the measured pressure value. The present invention does not rely on the accuracy of the reference pressure gauge, has high detection efficiency, wide pressure testing range, and the generated reference pressure precision has nothing to do with the testing range.

Description

Automatic testing system, method and device for pressure gauge

technical field

The invention relates to the technical field of instrumentation testing, in particular to an automated testing system, method and device for a pressure gauge.

Background technique

Pressure gauges (such as elastic element type general pressure gauges, pressure vacuum gauges and vacuum gauges) are the most commonly used instruments in various instruments. In order to ensure the high reliability of the pressure gauge, it must be calibrated frequently or Calibration. Depending on the specific requirements common to each different application, these calibrations must comply with relevant national or international standards. The test items of the pressure gauge can usually include test items such as zero point error detection, indication error detection, return error detection and slight displacement detection.

The traditional pressure gauge test scheme usually adopts the manual pressurization method. By comparing the values between the tested pressure gauge and the reference pressure gauge at several calibration points, the test efficiency and accuracy are low. Take the pressure gauge of an aircraft (also called a pressure indicating instrument or pressure gauge) as an example, since its stability and accuracy are directly related to the normal operation of the aircraft, frequent testing is required to ensure the stability and accuracy of its performance. The existing testing equipment is usually manually operated hydraulic pump or air pump to pressurize, on the one hand, it is easy to cause overpressure and damage the instrument;

At present, some test devices for assisting the measuring staff to test the pressure gauge are also provided in the prior art. Taking Chinese patent z12017208600722 as an example, it discloses a pressure calibration device: including a pressure calibration unit and a main control unit electrically connected to the pressure calibration unit , the pressure calibration unit is externally connected to the pressure instrument to be calibrated, the pressure calibration device is also integrated with a communication module, the communication module is electrically connected to the main control unit, and accesses a remote database through a network; wherein, the pressure calibration unit includes a gas The pressure generating unit, the pressure control module, the pressure measurement module and the pressure interface module are connected by the pipeline. The pressure measurement module and the pressure control module are respectively electrically connected to the main control unit; the pressure interface module is connected to an external pressure gauge, and the pressure measurement module provides the pressure standard Data, the high-pressure gas generated by the pressure generating unit enters the pressure control module through the gas pipeline, and reaches the pressure instrument to be calibrated through the pressure interface module; specifically, the pressure generating unit generates gas pressure through an air pump. However, in the above calibration scheme, a pressure measurement module including a standard gauge needs to be set up to provide pressure standard data. The accuracy of the test is highly dependent on the accuracy of the standard gauge (or reference pressure gauge). Once the accuracy of the standard gauge is defective, it will lead to The calibrated pressure gauge is inaccurate; at the same time, it is necessary to replace the standard gauge with different ranges to calibrate the tested pressure gauge of the corresponding range during the test, which reduces the test efficiency.

In summary, how to provide an automated test system for a pressure gauge that does not depend on the accuracy of the reference pressure gauge, has high detection efficiency, has a wide pressure test range, and has a high degree of automation is a technical problem that needs to be solved urgently in the art.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the deficiencies of the prior art and provide an automatic test system, method and device for a pressure gauge. The automatic test system provided by the invention converts the pressure parameters into physical parameters such as displacement and temperature that are easy to measure with high accuracy by pulling the piston through the slider, and indirectly calculates the theoretical pressure applied to the pressure gauge under test through the ideal gas formula as the reference pressure, The measurement error is obtained by comparing the reference pressure with the measured pressure of the pressure gauge under test. The invention does not need to set a reference pressure gauge, has high detection efficiency, and has the advantages of wide pressure test range, generated reference pressure accuracy independent of the test range, and high degree of automation.

To achieve the above-mentioned goals, the present invention provides the following technical solutions:

An automated testing system for a pressure gauge, comprising a rotating mechanism, a data acquisition mechanism and a data processing mechanism;

The rotating mechanism is provided with an installation part of the tested equipment, a linear guide rail, a slider and a piston; the installation part of the tested equipment is used to fix the pressure gauge under test on the rotating mechanism; the linear guide rail is fixedly installed on the rotating mechanism. On the mechanism and along the radial direction of the rotating mechanism, the slider is movably installed on the linear guide rail and can move along the radial direction of the rotating mechanism on the linear guide rail; the piston includes a piston cavity and a piston rod, and the piston cavity is fixedly installed On the rotating mechanism and between the installation part of the device under test and the slider, the piston cavity is connected with the pressure gauge under test through a conduit to form an air pressure channel, the piston rod is rigidly connected to the slider, and the slider is on a linear guide During the movement, the piston rod is driven to move, and the gas pressure in the piston cavity changes and acts on the measured pressure gauge through the aforementioned air pressure channel, and the measured pressure value P _e is obtained through the measured pressure gauge;

The data acquisition mechanism includes an atmospheric pressure sensor, an electronic temperature measurement structure and an electronic distance measurement structure. The atmospheric pressure sensor is used to detect atmospheric pressure information, and the electronic temperature measurement structure is configured to detect the temperature in the piston cavity corresponding to the aforementioned piston. information, the electronic ranging structure is corresponding to the aforementioned piston or slider set to detect the length information of the gas in the piston;

The data processing mechanism can receive the information detected by the aforementioned data acquisition mechanism, and obtain the initial atmospheric pressure P ₀ at the beginning of the test, the initial temperature T ₀ in the piston and the initial length L ₀ of the gas in the piston according to the detected information, and obtain the test process. The temperature change Δt in the piston and the gas length change ΔL in the piston are calculated by the following formula to obtain the theoretical pressure value ΔP,

and receiving the measurement information of the pressure gauge under test, and comparing the theoretical pressure value ΔP with the measured pressure value P _e to obtain the measurement error of the pressure gauge under test.

Further, the conduit is a hose, the piston cavity of the corresponding piston is provided with a gas output port, and one end of the hose is connected to the gas output port through a gas nozzle; Connect the gas input port of the pressure gauge under test during the test.

Further, the electronic ranging structure includes a distance sensor connected in communication with the data processing mechanism, the distance sensor is arranged corresponding to the piston rod to collect the position change of the piston rod, and sends the position change of the piston rod to the data processing mechanism as the piston. The change in the length of the inner gas ΔL; or, the distance sensor is installed at one end of the linear guide rail and is arranged on the outside of the slider, and the distance sensor is used to collect the position change of the slider when the rotating mechanism rotates and send it to the data processing mechanism as the inner part of the piston. Gas length change amount ΔL.

Further, the electronic ranging structure includes a camera, an image processor and a wireless communication structure; the camera is set corresponding to the piston or the slider, and is used to capture the image data of the piston or the slider and send it to the image processor; the image processing It is used to perform image recognition on the received image data of the piston or the slider to obtain the position change information of the piston rod or the slider; the position change of the piston rod is sent to the data processing mechanism through the wireless communication structure as the length of the gas in the piston The change amount ΔL, or the position change amount of the slider is sent to the data processing mechanism as the change amount ΔL of the gas length in the piston.

Further, the electronic temperature measurement structure includes a temperature sensor corresponding to the aforementioned piston cavity, and the temperature information in the piston cavity is collected by the temperature sensor and sent to the data processing mechanism, and the collected temperature information includes the initial temperature information in the piston at the beginning of the test. and information on the temperature change in the piston during the test.

Further, a rotational speed measurement unit and a rotational speed control unit are provided corresponding to the rotating mechanism, the data acquisition mechanism includes a test information collection unit to collect a plurality of test rotational speed information set by the user, and the rotational speed control unit can be based on the aforementioned test rotational speed information. After a speed test is completed, the speed of the rotating mechanism is automatically adjusted to the next test speed until the preset calibration points and/or travel requirements are met;

The rotational speed measuring unit is used to measure the rotational speed of the rotating mechanism and issue a comparison command when the rotational speed is fixed. According to the comparison command, the data processing mechanism is triggered to obtain the theoretical pressure value ΔP and compare it with the measured pressure value _Pe .

The present invention also provides a test method according to the aforementioned automated test system, comprising the following steps:

Fix the pressure gauge under test on the rotating mechanism through the installation part of the tested equipment;

Obtain the test speed information, and control the rotation of the rotating mechanism according to the test speed information. When the rotating mechanism reaches the test speed and the speed is constant, the measured pressure value P _e is obtained through the pressure gauge under test, and the test is obtained through the electronic temperature measurement structure and the electronic distance measurement structure. The temperature change Δt in the piston and the length change ΔL of the gas in the piston during the process;

According to the aforementioned temperature change Δt in the piston and the length change ΔL of the gas in the piston, combined with the initial atmospheric pressure P ₀ at the beginning of the test, the initial temperature T ₀ in the piston and the initial length L ₀ of the gas in the piston, the theoretical pressure value is obtained by calculating the following formula: ΔP,

The theoretical pressure value ΔP is compared with the aforementioned measured pressure value P _e to obtain the measurement error of the pressure gauge under test at the aforementioned test rotational speed.

Further, a rotational speed measurement unit and a rotational speed control unit should be provided in the rotating mechanism, the data acquisition mechanism includes a test information collection unit to collect a plurality of test rotational speed information set by the user, and the rotational speed control unit can be based on the aforementioned test rotational speed information. After a speed test is completed, the speed of the rotating mechanism is automatically adjusted to the next test speed until the preset calibration points and/or travel requirements are met;

The rotational speed measuring unit is used to measure the rotational speed of the rotating mechanism and issue a comparison command when the rotational speed is fixed. According to the comparison command, the data processing mechanism is triggered to obtain the theoretical pressure value ΔP and compare it with the measured pressure value _Pe .

The present invention also provides an intelligent pressure application device for pressure gauge testing, comprising a rotating mechanism, and the rotating mechanism is provided with a test equipment installation part, a linear guide rail, a slider and a piston;

The device under test installation part is used to fix the pressure gauge under test on the rotating mechanism;

The linear guide rail is fixedly installed on the rotating mechanism and arranged along the radial direction of the rotating mechanism, and the slider is movably installed on the linear guide rail and can move along the radial direction of the rotating mechanism on the linear guide rail;

The piston includes a piston cavity and a piston rod. The piston cavity is fixedly installed on the rotating mechanism and is located between the installation part of the tested equipment and the slider. The piston cavity is connected to the tested pressure gauge through a conduit to form an air pressure channel. The piston rod is rigidly connected to the slider, the slider drives the piston rod to move when the slider moves on the linear guide rail, and the gas pressure in the piston cavity changes and acts on the measured pressure gauge through the aforementioned air pressure channel.

Further, the moving distance of the slider on the linear guide is adjusted by adjusting the rotational speed of the rotating mechanism, so as to adjust the air pressure acting on the pressure gauge under test.

Compared with the prior art, the present invention has the following advantages and positive effects due to the adoption of the above technical solutions, as an example: the automatic test system of the pressure gauge pulls the piston through the slider, and converts the pressure parameters into easy and high-precision measurement. The physical parameters such as displacement and temperature are calculated indirectly through the ideal gas formula, and the theoretical pressure applied to the pressure gauge under test is used as the reference pressure, and the measurement error is obtained by comparing the reference pressure with the measured pressure of the pressure gauge under test. The invention is suitable for the pressure reduction test of the pressure gauge, without setting a reference pressure gauge (so that the calibration does not depend on the accuracy of the reference pressure gauge), the detection efficiency is high, the pressure test range is wide, the generated reference pressure accuracy is independent of the test range, and the degree of automation high advantage. At the same time, since there is no need to set a reference pressure gauge, the number of calibration points can be set more as required.

Description of drawings

FIG. 1 is a structural example diagram of an automated testing system for a pressure gauge provided by an embodiment of the present invention.

FIG. 2 is a schematic structural diagram of an initially unstretched state of the piston according to an embodiment of the present invention.

FIG. 3 is a schematic structural diagram of a piston in a stretched state during rotation according to an embodiment of the present invention.

FIG. 4 is a schematic diagram of information collection and transmission of a system provided by an embodiment of the present invention.

FIG. 5 is a schematic diagram of information processing for rotational speed control and rotational speed measurement provided by an embodiment of the present invention.

Description of reference numbers:

system 10;

Rotation mechanism 100, rotation center 101, tested equipment mounting part 110, linear guide 120, slider 130, piston 140, piston cavity 141, piston rod 142, gas in the piston 143, conduit 150;

Data acquisition mechanism 200, atmospheric pressure sensor 210, electronic temperature measurement structure 220, electronic distance measurement structure 230;

data processing agency 300;

Pressure gauge under test 20.

Detailed ways

The automatic testing system, method and device of the pressure gauge disclosed in the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the technical features or combinations of technical features described in the following embodiments should not be considered isolated, and they can be combined with each other to achieve better technical effects. In the drawings of the following embodiments, the same reference numerals appearing in the various drawings represent the same features or components, which may be used in different embodiments. Therefore, once an item is defined in one figure, it need not be discussed further in subsequent figures.

It should be noted that the structures, proportions, sizes, etc. shown in the accompanying drawings in this specification are only used to cooperate with the contents disclosed in the specification, so as to be understood and read by those who are familiar with the technology, and are not used to limit the invention. The limited conditions for implementation, any structural modification, change in proportional relationship or adjustment of size, shall fall within the scope of the technical content disclosed in the invention without affecting the efficacy and purpose of the invention. within the range. The scope of the preferred embodiments of the present invention includes additional implementations in which the functions may be performed out of the order described or discussed, including performing the functions in a substantially simultaneous manner or in the reverse order depending upon the functions involved, which should be Embodiments of the invention will be understood by those skilled in the art to which the embodiments of the invention pertain.

Techniques, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the authorized description. In all examples shown and discussed herein, any specific value should be construed as illustrative only and not as limiting. Accordingly, other examples of exemplary embodiments may have different values.

Example

Referring to Fig. 1, it is an automatic test system for a pressure gauge provided by the present invention.

The system 10 includes a rotation mechanism 100 , a data acquisition mechanism 200 and a data processing mechanism 300 .

The rotating mechanism 100 can rotate around the rotation center 101 under the driving of a rotating driving device, such as a motor. The rotating mechanism 100 is provided with a device-under-test mounting part 110 , a linear guide 120 , a slider 130 and a piston 140 , and a top view of the rotating mechanism 100 is illustrated in FIG. 1 .

The device under test mounting portion 110 is used for fixing the pressure gauge 20 under test on the rotating mechanism 100 . The pressure gauge 20 under test is the object to be tested as the device under test. The fixed connection method of the pressure gauge 20 under test on the rotating mechanism 100 includes but is not limited to screw connection, snap connection, clamping connection or a combination of various connection methods, as long as the pressure gauge 20 under test can be fixed on the rotating mechanism. The connection methods on the mechanism 100 can be applied to the device under test mounting portion 110 .

The linear guide rail 120 is fixedly installed on the rotating mechanism and arranged along the radial direction of the rotating mechanism, and the sliding block 130 is movably installed on the linear guide rail 120 . The linear guide 120 is used to limit the moving range of the slider 130 to make it move linearly along the radial direction. When the rotating mechanism 100 rotates, the slider 130 can move outward along the radial direction of the rotating mechanism on the linear guide rail 120 under the action of centrifugal force. When the rotating mechanism 100 stops rotating, the sliding block is no longer subjected to centrifugal force, and the sliding block 130 can move inward on the linear guide 120 along the radial direction of the rotating mechanism to return to the initial position.

In this embodiment, the sliding block 130 can be a heavy block, and the movable installation method of the sliding block and the linear guide rail can be based on a matching groove or convex structure. By way of example and not limitation, for example, the upper surface of the linear guide rail is provided with an inverted T-shaped groove (the cross section of the groove is an inverted T-shaped), and the bottom of the slider 130 is provided with a T-shaped protrusion matching the aforementioned groove. The block can move linearly on the linear guide and prevent the slider from disengaging from the guide.

The piston 140 is located inside the sliding block 130 , that is, the piston 140 is located between the installation part 110 of the device under test and the sliding block 130 .

Specifically, as shown in FIG. 2 , the piston 140 includes a piston cavity 141 (or called a cylinder or cylinder) and a piston rod 142 . The piston chamber 141 is fixedly installed on the rotating mechanism 100 and is located between the installation part 110 of the device under test and the slider 130. The piston chamber 141 is connected with the pressure gauge 20 to be tested through the conduit 150 to form an air pressure channel. The gas pressure in the piston chamber 141 is applied to the pressure gauge 20 under test. The piston rod 142 is rigidly connected to the slider, and the slider drives the piston rod to move when the slider moves on the linear guide rail, and the gas pressure in the piston cavity changes and acts on the pressure gauge under test through the aforementioned air pressure channel. The pressure gauge obtains the measured pressure value P _e .

In specific implementation, the piston cavity 141 is a shell structure with a cavity, the cavity is the gas 143 in the piston, and the cross-sectional area of the piston cavity is a constant value, that is, the cross-sectional area is the same everywhere. One end of the piston rod 142 may have an enlarged head, and the enlarged head of the piston rod 142 is in sealing contact with the inner wall of the piston cavity 141 and can reciprocate in the piston cavity 141 . Preferably, the enlarged head of the piston rod 142 is provided with multiple piston sealing rings to improve the tightness of the contact between the enlarged head of the piston rod and the piston cavity. The other end of the piston rod 142 is rigidly connected to the slider 130, so that the slider 130 can pull the piston rod 142 to move together when the slider 130 moves outward, thereby changing the gas pressure in the piston cavity (pressure reduction), and then passing through the aforementioned air pressure channel Negative pressure is generated on the pressure gauge 20 under test, and the pressure gauge under test performs pressure measurement to obtain the measured pressure value P _e .

The conduit 150 is preferably a hose, and the piston cavity 141 of the corresponding piston is provided with a gas output port. One end of the hose can be connected to the gas output port through a gas nozzle; the other end of the hose is provided corresponding to the installation part of the tested equipment. , you can connect the gas input port of the pressure gauge under test during the test.

After receiving the test command, the rotating mechanism starts to rotate. Due to the centrifugal force, the slider moves outward in the radial direction under the limit of the linear guide (the direction of movement shown by the arrow in Figure 2), while pulling the piston rod, the piston cavity The gas pressure inside changes, see Figure 3. The air pressure change acts on the pressure gauge under test through the aforementioned air pressure channel, and generates pressure on the pressure gauge under test. The pressure is related to the displacement of the piston (or displacement of the slider), current temperature information, air pressure information and other parameters.

According to the ideal gas equation of state, we have:

PV=nRT

Where P is the gas pressure, V is the gas volume, n is the number of moles of the gas, R is the universal gas constant of the gas, and T is the gas temperature.

The cross-sectional area of the piston cavity in the piston is the same everywhere, so the air volume in the piston can be calculated by the following formula:

V=LS

Where L is the length of the gas in the piston, and S is the cross-sectional area of the piston. In this case, the ideal gas equation of state transforms into:

Since the air quality in the piston basically does not change, that is, the number of moles basically does not change, it can be considered that the parameters n, R and S in the above formula are all constants, according to which:

The following formula can be obtained:

PL=KT

Assuming that in the initial state (before the test starts), the initial atmospheric pressure is P ₀ , the initial temperature in the piston is T ₀ , and the initial length of the gas in the piston is L ₀ . After entering the above formula, the formula is obtained:

P ₀ L ₀ =KT ₀

After the test starts, control the rotation of the rotating mechanism. When the rotating mechanism reaches the preset constant speed, the piston is pulled by the centrifugal force due to the slider (heavy block), which changes the volume of gas in the piston (the volume increases). The following relationship:

(P ₀ +ΔP)(L ₀ +ΔL)=K(T ₀ +Δt)

Among them, ΔP is the change of the gas pressure in the piston; ΔL is the change of the gas length in the piston, which is reflected as the change of the piston position or the position of the slider; Δt is the change of the temperature in the piston.

The change amount of gas pressure in the piston ΔP is the pressure value (pressure) acting on the pressure gauge under test. The calculation formula of ΔP is as follows:

That is to say, after obtaining the temperature change Δt in the piston and the length change ΔL of the gas in the piston during the test, the initial atmospheric pressure P ₀ at the beginning of the test, the initial temperature T ₀ in the piston and the initial length of the gas in the piston can be combined L ₀ and other parameters, calculate the theoretical pressure value ΔP of the pressure gauge under test by the above formula.

Accordingly, the system provided in this embodiment further includes a data collection mechanism 200 and a data processing mechanism 300 .

The data acquisition mechanism 200 includes an atmospheric pressure sensor 210 , an electronic temperature measurement structure 220 and an electronic distance measurement structure 230 . The barometric pressure sensor 210 is used to detect barometric pressure information. The electronic temperature measuring structure 220 is configured to detect the temperature information in the piston cavity corresponding to the aforementioned piston. The electronic distance measuring structure 230 is configured to detect the length information of the gas in the piston corresponding to the aforementioned piston or slider.

The data processing mechanism 300 can receive the information detected by the aforementioned data acquisition mechanism and obtain the initial atmospheric pressure P ₀ at the beginning of the test, the initial temperature T ₀ in the piston and the initial length L ₀ of the gas in the piston according to the detected information, and obtain the test information. During the process, the temperature change Δt in the piston and the gas length change ΔL in the piston are calculated, and the theoretical pressure value ΔP is obtained by the following formula:

The data processing mechanism 300 may also receive the measurement information of the pressure gauge under test, and compare the theoretical pressure value ΔP with the measured pressure value _Pe , so as to obtain the measurement error of the pressure gauge under test.

In this embodiment, the data processing mechanism may be integrated with the rotating mechanism, or may be independently provided on the host computer.

When the upper computer is used to set the data processing mechanism, preferably, the pressure gauge under test and the data acquisition mechanism transmit the detected data to the upper computer through wireless data transmission. After the data processing mechanism on the upper computer receives the data, data storage and processing, see Figure 4. Preferably, a wireless transmission device is integrated on the rotating mechanism to send detected data such as the detected displacement information, the gas temperature information in the piston, and the rotational speed information of the rotating mechanism to the data processing mechanism.

In one embodiment, the electronic ranging structure may include a distance sensor in communication with the data processing mechanism.

In specific implementation, the distance sensor may be set corresponding to the piston rod to collect the position change of the piston rod, and send the position change of the piston rod to the data processing mechanism as the change of the gas length ΔL in the piston.

Alternatively, the distance sensor can also be installed at one end of the linear guide rail and arranged on the outside of the slider. The distance sensor collects the position change of the slider when the rotating mechanism rotates and sends it to the data processing mechanism as the change in the length of the gas in the piston ΔL .

In another embodiment, the electronic ranging structure can also use an image recognition device. Specifically, the electronic ranging structure includes a camera, an image processor and a wireless communication structure; the camera is set corresponding to the piston or the slider, and is used to capture the image data of the piston or the slider and send it to the image processor; the image The processor is used to perform image recognition on the received image data of the piston or the slider to obtain the position change information of the piston rod or the slider; send the position change of the piston rod to the data processing mechanism as the gas in the piston through the wireless communication structure The length change amount ΔL, or the position change amount of the slider is sent to the data processing mechanism as the length change amount ΔL of the gas in the piston.

In this embodiment, the electronic temperature measurement structure preferably adopts a temperature sensor, and optionally, the temperature sensor is integrated on the piston. Specifically, the electronic temperature measurement structure may include a temperature sensor corresponding to the aforementioned piston cavity. The temperature information in the piston cavity is collected by the temperature sensor and sent to the data processing mechanism. The collected temperature information may include the initial temperature in the piston when the test starts. information and information on the change in temperature in the piston during the test.

Referring to FIG. 5 , preferably, a rotational speed measuring unit and a rotational speed control unit are further provided corresponding to the rotating mechanism. In specific settings, the rotational speed measuring unit may be integrated into a rotating mechanism for setting, and the rotational speed control unit may be integrated into a data processing mechanism for setting.

The data collection mechanism further includes a test information collection unit to collect a plurality of test rotational speed information set by the user. As an example of a typical method, but not a limitation, for example, setting a user interface in the host computer as a test information collection unit for the user to directly input multiple required test speed information, or reading the set test speed information under the preset storage path through the user interface file, or receive the test speed setting file imported by the user through the user interface.

During the test, the rotational speed control unit can automatically adjust the rotational speed of the rotating mechanism to the next test rotational speed after one rotational speed test is completed according to the aforementioned test rotational speed information, until all the test rotational speeds are completed and the preset calibration points and/or itinerary requirements.

The rotational speed measuring unit is used to measure the rotational speed of the rotating mechanism and issue a comparison command when the rotational speed is fixed. According to the comparison instruction, the test system can trigger the data processing mechanism to perform data processing, and after obtaining the theoretical pressure value ΔP, compare the theoretical pressure value ΔP with the measured pressure value _Pe , so as to obtain the measurement error of the pressure gauge under test. .

Through the cooperation of the rotational speed control unit and the rotational speed measurement unit, the test system can automatically complete the error measurement of the pressure gauge under test at multiple test rotational speeds until the preset calibration points and stroke requirements are met.

The above technical solution provided by the present invention converts the pressure into physical quantities such as displacement, temperature, etc. that are easy to be measured with high precision by pulling the piston through the slider, indirectly calculates the reference pressure applied to the pressure gauge under test, and can easily control the rotation mechanism through the The rotational speed is used to accurately control the pressure value of the pressure gauge under test, which solves the problems of the existing technology that the calibration is highly dependent on the accuracy of the reference pressure gauge, the detection efficiency is low, and the number of calibration points is small. The pressure accuracy has nothing to do with the test range and the advantages of a high degree of automation.

In the above technical solution, the pressure gauge under test is the main body to be measured, and the electronic distance measuring device, such as a distance sensor, is used to measure the displacement of the piston or the slider along the radius, and the piston is used to convert the displacement of the slider into the displacement applied to the measured object. The reference pressure of the pressure gauge, the guide rail is used to limit the sliding movement range, the conduit is used to connect the pressure gauge under test and the piston to form an air pressure channel, the electronic temperature measurement structure - such as a temperature sensor is used to detect temperature information, and an atmospheric pressure sensor is used to measure Atmospheric pressure. The data acquisition structure is used to collect the detection data of each sensor, and send the detection data to the data processing mechanism for data processing by means of wireless data transmission. The data processing mechanism is configured to: calculate the theoretical pressure value according to a preset theoretical pressure calculation model, and compare it with the measured pressure value detected by the measured pressure gauge. Further, the data processing mechanism can also be configured to: acquire the stored detection data and calculation comparison data, and perform error analysis and calibration.

A typical procedure for testing with the automated test system of the above pressure gauge can be as follows:

S100, the pressure gauge under test is fixedly installed on the rotating mechanism through the installation part of the equipment under test.

S200, obtain the test speed information, control the rotation of the rotating mechanism according to the test speed information, when the rotating mechanism reaches the test speed and the speed is constant, obtain the measured pressure value P _e through the pressure gauge under test, and simultaneously use the electronic temperature measuring structure and the electronic distance measuring structure The temperature change Δt in the piston and the gas length change ΔL in the piston during the test were obtained.

S300, according to the aforementioned temperature change Δt in the piston and the length change ΔL of the gas in the piston, in combination with the initial atmospheric pressure P ₀ at the beginning of the test, the initial temperature T ₀ in the piston and the initial length L ₀ of the gas in the piston, the theoretical calculation is obtained by the following formula pressure value ΔP,

S400 , compare the theoretical pressure value ΔP with the aforementioned measured pressure value P _e to obtain the measurement error of the pressure gauge under test at the aforementioned test rotational speed.

The present embodiment will be described in detail below by taking the calibration of a manometer with a range of -10KPa-0Pa as an example.

Step 1, connect the gas pressure measurement input port of the pressure gauge to the gas nozzle of the output port of the piston through a hose, and place the pressure gauge on the installation part of the tested device of the rotating mechanism for fixing. Connect the measurement output of the manometer to a wireless data transmission device via a wire.

Step 2: Before the calibration starts, the initial atmospheric pressure P ₀ =101325Pa is read through the air pressure sensor, the current piston temperature T ₀ =280K is read through the thermometer, and the initial length of the piston L ₀ =15cm is obtained through the ranging structure (that is, the piston is in length of gas in the piston in the unstretched state).

Step 3, start the rotating mechanism.

Step 4: Gradually increase the rotational speed of the rotating mechanism to a certain constant rotational speed (controlled according to the preset test rotational speed), obtain the piston length change ΔL=0.5mm (length increase), and the temperature in the piston becomes T=279K. These data are obtained through After the distance measuring structure and the thermometer are measured, they are transmitted to the data processing mechanism through the wireless data transmission device. The measured values of the manometer are also transmitted to the data processing unit via a wireless data transmission device.

Based on the preset theoretical pressure calculation model, the data processing mechanism substitutes ΔL=0.5mm, Δt=279K-280K=-1K into the previous pressure calculation formula, and the obtained theoretical pressure change is as follows:

The data storage unit of the data processing mechanism records the value, and compares the value with the received pressure gauge measurement value through the comparison unit to obtain the measurement error.

Step 5: Adjust the speed of the rotating mechanism according to the test speed information, and repeat Step 4 until the required calibration points and stroke requirements are met.

Another embodiment of the present invention also provides an intelligent pressure application device for pressure gauge testing.

The intelligent pressing device includes a rotating mechanism, and the rotating mechanism is provided with an installation part of the tested equipment, a linear guide rail, a sliding block and a piston.

The installation part of the device under test is used for fixing the pressure gauge under test on the rotating mechanism.

The linear guide rail is fixedly installed on the rotating mechanism and arranged along the radial direction of the rotating mechanism, and the sliding block is movably installed on the linear guide rail and can move along the radial direction of the rotating mechanism on the linear guide rail.

The piston includes a piston cavity and a piston rod. The piston cavity is fixedly installed on the rotating mechanism and is located between the installation part of the tested equipment and the slider. The piston cavity is connected to the tested pressure gauge through a conduit to form an air pressure channel. The piston rod is rigidly connected to the slider, the slider drives the piston rod to move when the slider moves on the linear guide rail, and the gas pressure in the piston cavity changes and acts on the measured pressure gauge through the aforementioned air pressure channel.

In this embodiment, the intelligent pressure applying device can adjust the moving distance of the slider on the linear guide rail by adjusting the rotational speed of the rotating mechanism, thereby adjusting the air pressure acting on the pressure gauge under test.

Specifically, the intelligent pressure applying device may include a rotational speed measurement unit and a rotational speed control unit. The rotational speed measuring unit is used to measure the rotational speed of the rotating mechanism. The rotational speed control unit can automatically adjust the rotational speed of the rotating mechanism to the next test rotational speed according to the preset test rotational speed information after one rotational speed test is completed until the preset calibration points and/or stroke requirements are met.

For other technical features, refer to the previous embodiments, which will not be repeated here.

In the above description, the disclosure of the present invention is not intended to limit itself in these respects. Rather, the various components may be selectively and operatively combined in any number within the intended scope of this disclosure. Additionally, terms like "includes," "includes," and "has" should by default be construed as inclusive or open, rather than exclusive or closed, unless explicitly defined to the contrary. All technical, scientific or other terms have the meaning as understood by those skilled in the art unless they are defined to the contrary. Common terms found in dictionaries should not be interpreted too ideally or too practically in the context of related technical documents, unless this disclosure explicitly defines them as such. Any changes and modifications made by those of ordinary skill in the field of the present invention according to the above disclosure fall within the protection scope of the claims.

Claims (10)

1. an automatic test system of a pressure gauge, is characterized in that: comprise rotating mechanism, data acquisition mechanism and data processing mechanism; The rotating mechanism is provided with an installation part of the tested equipment, a linear guide rail, a slider and a piston; the installation part of the tested equipment is used to fix the pressure gauge under test on the rotating mechanism; the linear guide rail is fixedly installed on the rotating mechanism. On the mechanism and along the radial direction of the rotating mechanism, the slider is movably installed on the linear guide rail and can move along the radial direction of the rotating mechanism on the linear guide rail; the piston includes a piston cavity and a piston rod, and the piston cavity is fixedly installed On the rotating mechanism and between the installation part of the device under test and the slider, the piston cavity is connected with the pressure gauge under test through a conduit to form an air pressure channel, the piston rod is rigidly connected to the slider, and the slider is on a linear guide During the movement, the piston rod is driven to move, and the gas pressure in the piston cavity changes and acts on the measured pressure gauge through the aforementioned air pressure channel, and the measured pressure value P _e is obtained through the measured pressure gauge; The data acquisition mechanism includes an atmospheric pressure sensor, an electronic temperature measurement structure and an electronic distance measurement structure. The atmospheric pressure sensor is used to detect atmospheric pressure information, and the electronic temperature measurement structure is configured to detect the temperature in the piston cavity corresponding to the aforementioned piston. information, the electronic ranging structure is corresponding to the aforementioned piston or slider set to detect the length information of the gas in the piston; The data processing mechanism can receive the information detected by the aforementioned data acquisition mechanism, and obtain the initial atmospheric pressure P ₀ at the beginning of the test, the initial temperature T ₀ in the piston and the initial length L ₀ of the gas in the piston according to the detected information, and obtain the test process. The temperature change △t in the piston and the gas length change △L in the piston are calculated by the following formula to obtain the theoretical pressure value △P,

; and receiving the measurement information of the pressure gauge under test, and comparing the theoretical pressure value ΔP with the measured pressure value P _e to obtain the measurement error of the pressure gauge under test. 2. The automated testing system according to claim 1, wherein the conduit is a hose, the piston cavity of the corresponding piston is provided with a gas outlet, and one end of the hose is connected to the gas outlet through a gas nozzle; The other end of the pipe is set corresponding to the installation part of the equipment under test, and is used to connect the gas input port of the pressure gauge under test during the test. 3. The automated testing system according to claim 1 or 2, wherein the electronic ranging structure comprises a distance sensor that is communicatively connected with a data processing mechanism, and the distance sensor corresponding to the piston rod is arranged to collect the position of the piston rod change amount, send the position change amount of the piston rod to the data processing mechanism as the change amount ΔL of the gas length in the piston; or, the distance sensor is installed on one end of the linear guide rail corresponding to the outer side of the slider, and the distance sensor collects When the rotating mechanism rotates, the position change of the slider is sent to the data processing mechanism as the change ΔL of the gas length in the piston. 4. The automated testing system according to claim 1 or 2, wherein: the electronic ranging structure comprises a camera, an image processor and a wireless communication structure; the camera is arranged corresponding to a piston or a slider, and is used for photographing the piston The image data of the piston or the slider is sent to the image processor; the image processor is used to perform image recognition on the received image data of the piston or the slider to obtain the position change information of the piston rod or the slider; through the wireless communication structure The position change of the piston rod is sent to the data processing mechanism as the change in the gas length in the piston ΔL, or the position change of the slider is sent to the data processing mechanism as the change in the length of the gas in the piston ΔL. 5. The automated testing system according to claim 1 or 2, wherein the electronic temperature measurement structure comprises a temperature sensor corresponding to the aforementioned piston cavity, and the temperature information in the piston cavity is collected by the temperature sensor and sent to the The temperature information collected by the data processing mechanism includes the initial temperature information in the piston at the beginning of the test and the change information of the temperature in the piston during the test. 6. The automated testing system according to claim 1 or 2, wherein: a rotational speed measurement unit and a rotational speed control unit are provided corresponding to the rotating mechanism, and the data acquisition mechanism comprises a test information acquisition unit to collect multiple set of users. The rotational speed control unit can automatically adjust the rotational speed of the rotating mechanism to the next test rotational speed after one rotational speed test is completed according to the aforementioned test rotational speed information, until the preset calibration points and/or travel requirements are met; The rotational speed measuring unit is used to measure the rotational speed of the rotating mechanism and issue a comparison command when the rotational speed is fixed. According to the comparison command, the data processing mechanism is triggered to obtain the theoretical pressure value ΔP and compare it with the measured pressure value _Pe . 7. A test method according to the automated test system described in any one of claims 1-6, is characterized in that comprising the steps: Fix the pressure gauge under test on the rotating mechanism through the installation part of the tested equipment; Obtain the test speed information, and control the rotation of the rotating mechanism according to the test speed information. When the rotating mechanism reaches the test speed and the speed is constant, the measured pressure value P _e is obtained through the pressure gauge under test, and the test is obtained through the electronic temperature measurement structure and the electronic distance measurement structure. During the process, the temperature change in the piston Δt and the change in the length of the gas in the piston ΔL; According to the temperature change Δt in the piston and the length change ΔL of the gas in the piston, combined with the initial atmospheric pressure P ₀ at the beginning of the test, the initial temperature T ₀ in the piston and the initial length L ₀ of the gas in the piston, the theoretical calculation is obtained by the following formula: Pressure value △P,

; The theoretical pressure value ΔP is compared with the aforementioned measured pressure value P _e to obtain the measurement error of the pressure gauge under test at the aforementioned test speed. 8. testing method according to claim 7, is characterized in that: corresponding described rotating mechanism is provided with rotating speed measuring unit and rotating speed control unit, and described data acquisition mechanism comprises test information collecting unit to collect the multiple test rotating speed of user's setting information, the rotational speed control unit can automatically adjust the rotational speed of the rotating mechanism to the next test rotational speed after one rotational speed test is completed according to the aforementioned test rotational speed information, until the preset number of calibration points and/or travel requirements are met; The rotational speed measuring unit is used to measure the rotational speed of the rotating mechanism and issue a comparison command when the rotational speed is fixed. According to the comparison command, the data processing mechanism is triggered to obtain the theoretical pressure value ΔP and compare it with the measured pressure value _Pe . 9. An intelligent pressure-applying device for pressure gauge testing, characterized in that it comprises a rotating mechanism, and the rotating mechanism is provided with a test-equipment mounting part, a linear guide rail, a slider and a piston; The device under test installation part is used to fix the pressure gauge under test on the rotating mechanism; The linear guide rail is fixedly installed on the rotating mechanism and arranged along the radial direction of the rotating mechanism, and the slider is movably installed on the linear guide rail and can move along the radial direction of the rotating mechanism on the linear guide rail; The piston includes a piston cavity and a piston rod. The piston cavity is fixedly installed on the rotating mechanism and is located between the installation part of the tested device and the slider. The piston cavity is connected with the tested pressure gauge through a conduit to form an air pressure channel. The piston rod is rigidly connected to the slider, the slider drives the piston rod to move when the slider moves on the linear guide rail, and the gas pressure in the piston cavity changes and acts on the measured pressure gauge through the aforementioned air pressure channel. 10 . The intelligent pressure applying device according to claim 9 , wherein the moving distance of the slider on the linear guide rail is adjusted by adjusting the rotational speed of the rotating mechanism, thereby adjusting the air pressure acting on the pressure gauge under test. 11 .

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