CN111220322A - Negative step calibrating device - Google Patents
Negative step calibrating device Download PDFInfo
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- CN111220322A CN111220322A CN201911084693.6A CN201911084693A CN111220322A CN 111220322 A CN111220322 A CN 111220322A CN 201911084693 A CN201911084693 A CN 201911084693A CN 111220322 A CN111220322 A CN 111220322A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L25/00—Testing or calibrating of apparatus for measuring force, torque, work, mechanical power, or mechanical efficiency
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L27/00—Testing or calibrating of apparatus for measuring fluid pressure
- G01L27/002—Calibrating, i.e. establishing true relation between transducer output value and value to be measured, zeroing, linearising or span error determination
- G01L27/005—Apparatus for calibrating pressure sensors
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- Analytical Chemistry (AREA)
- Measuring Fluid Pressure (AREA)
Abstract
The invention provides a pressure sensor calibration device which is simple in structure and can generate good negative step pressure signals. The device adopts the principle that solid or liquid carbon dioxide generates a negative step pressure signal when absorbing heat and changing into gas rupture of membranes to calibrate the sensor. A negative step calibration device comprises an upper cover, a bolt, a cavity, an electrode, a pressure relief opening, a membrane pressing screw, an electric heating wire, a support, a filling opening, a valve core, solid or liquid carbon dioxide and the like. This device can produce different negative step signal through what of filling carbon dioxide in the thickness of changing the diaphragm and the device, is benefited from pressure sensor's calibration, can effectively protect experimental apparatus and experimental environment simultaneously. And the method has the advantages of low experiment cost, simple and convenient operation, no pollution and good experiment effect, and is suitable for actual experiment places.
Description
Technical Field
The invention belongs to the field of non-standard instrument experiment calibration, and particularly relates to a negative step calibration device.
Background
With the development of aerospace technology and the production requirements of weapon industry and robot industry, the pressure sensor has great requirements as a key component in testing, and the calibration of the pressure sensor is also necessary. At present, the static calibration of the pressure sensor is far from meeting the requirement, and the dynamic load condition of the pressure sensor in actual industrial production or scientific research is far more than that of the static and quasi-static processes, so that the dynamic calibration evaluation of the pressure sensor is extremely important. Step response testing is a good method for pressure sensor dynamic calibration studies.
The techniques for generating positive or negative step loads are known in the art and include the following approaches: firstly, a shock tube is adopted to form a positive step pressure of 0.05MPa-10MPa, and the reference area of the force sensor is also required to be considered for the specifically generated step load, so that the method is suitable for dynamic calibration of the low-range pressure sensor; secondly, a negative step load is formed by adopting a method of shearing a steel wire rope, the instantaneous effect and the stability are difficult to ensure by manual shearing at present, for example, an electric switch is adopted for cutting off to improve the shearing speed, or a standard mass block is magnetized and replaces the conventional steel wire rope by electromagnetism, so that the response speed is improved and the stability is improved; thirdly, a pneumatic impact method based on the Pascal principle is adopted, and a push rod acts on a sensor to be measured through the instantaneous pressure of an air cylinder to form a positive step load; and fourthly, unloading is carried out by adopting a brittle material instantaneous fracture mode to form negative step load, the device is just complementary with the characteristics of the shock tube, the pressure rise time of the device is slower than that of the shock tube, the low-frequency characteristic of the sensor is easily obtained, the amplitude value which can be reached by the device is far higher than that of the shock tube, and the pressure duration time of the platform is also far higher than that of the shock tube.
In order to dynamically calibrate the sensor in the medium load range, a small laboratory usually adopts a conventional manual shearing mode and a brittle material fracture mode to realize the generation of the step load. However, it is difficult to realize the pneumatic impact by using the electromagnetic form and the cylinder, and the requirements for the test site and the test cost are greatly increased, so that it is difficult to use the pneumatic impact in the actual test site.
Disclosure of Invention
The invention provides a negative step calibration device. The sensor calibration device is simple in structure, can generate abundant frequency signals and amplitude signals to calibrate the sensor, and can obtain dynamic parameters of the sensor under high pressure and calibrate the sensor under the high pressure condition. The invention is suitable for practical experimental places.
The invention is realized by adopting the following technical scheme: a negative step calibration device comprises an upper cover and a cavity, wherein the upper cover is arranged at an opening above the cavity, the upper cover is provided with an installation through hole for installing a pressure sensor, one side wall of the cavity is provided with two electrode through holes, two electrodes respectively penetrate through the side wall of the cavity through one electrode through hole and enter the cavity, the electrodes are insulated from the cavity, and the two electrodes are connected with an electric heating wire between the end parts of the two electrodes in the cavity; the other side wall of the cavity is provided with a step-shaped through hole and a carbon dioxide filling opening, the through hole with a small middle caliber of the step-shaped through hole is directly communicated with the inside of the cavity, the carbon dioxide filling opening is communicated with the through hole with a large middle caliber of the step-shaped through hole, a valve core is arranged in the through hole with a large middle caliber of the step-shaped through hole to plug the through hole, the bottom of the cavity is provided with a step-shaped pressure relief opening, the pressure relief opening with a small middle caliber of the step-shaped pressure relief opening is directly communicated with the inside of the cavity, a membrane is arranged in the pressure relief opening with a large middle caliber of.
During the experiment, the high-precision sensor and the calibrated sensor are installed in the installation through hole. At the moment, the cavity and the brittle metal diaphragm at the pressure relief opening jointly enclose a closed empty chamber. Filling liquid carbon dioxide into the empty chamber, wherein the filling process comprises the following steps: and withdrawing the valve core outwards until the carbon dioxide filling port is communicated with the through hole with the small caliber in the ladder-shaped through hole, filling liquid carbon dioxide into the closed empty chamber through the filling port, and closing the valve core after filling. The two electrodes are electrified, the electric heating wire gradually heats and slowly heats liquid carbon dioxide in the cavity to gradually change the liquid carbon dioxide into gas. The pressure in the device will gradually increase to a high level before the carbon dioxide gas breaks the membrane. Therefore, the invention can calibrate the pressure sensor with high negative steps.
When the high pressure in the cavity exceeded the shear strength of diaphragm, the diaphragm took place to cut and broke, and carbon dioxide gas discharges rapidly through the pressure release mouth, makes the negative step pressure signal who generates have precipitous back edge, produces abundant frequency signal, can reach good negative step calibration effect.
According to the negative step calibration device, the caliber of the through hole in the diaphragm pressing screw is as large as that of the pressure relief opening with the small caliber of the step-shaped pressure relief opening, so that high-pressure carbon dioxide gas for breaking the diaphragm can escape in a large amount instantly.
In the negative step calibration device, the upper end face of the diaphragm pressing screw is designed to be a V-shaped groove, the inner edge of the V-shaped groove is higher than the outer edge by 0.2-0.5mm, and the inner edge of the V-shaped groove is in contact with the diaphragm. The diaphragm pressing screw is designed by adopting a V-shaped groove, the inner edge (the inner edge close to the through hole) of the diaphragm pressing screw is 0.2-0.5mm higher than the outer edge, the diaphragm can generate local stress concentration at the extruded part acting with the V-shaped groove, the diaphragm can be broken easily after bearing the internal high pressure, and the diaphragm part sheared during the diaphragm breaking can be blown out completely instead of puncturing the diaphragm into small holes in a flowering shape, so that the diaphragm pressing screw is more beneficial to instantly and rapidly gushing out carbon dioxide gas in a large quantity.
The negative step calibration device is characterized in that an opening is formed in the upper portion of the cavity, the upper cover is installed at the opening in the upper portion of the cavity through bolts, and installation through holes are formed in the upper cover. The carbon dioxide may be in a solid or liquid state. If the carbon dioxide is solid, the filling process is as follows: opening the upper cover, closing the valve core, putting the solid carbon dioxide into the hollow chamber, covering the upper cover, and screwing the bolt; if the carbon dioxide is in a liquid state, the filling process is as follows: and withdrawing the valve core outwards until the carbon dioxide filling port is communicated with the through hole with the small caliber in the ladder-shaped through hole, filling liquid carbon dioxide into the closed empty chamber through the filling port, and closing the valve core after filling.
In the above negative step calibration device, 4 pressure sensors are uniformly mounted on the upper cover in a circumferential shape: the device comprises a high-precision sensor, three calibrated sensors or three high-precision sensors and one calibrated sensor, and achieves the purpose of one-calibration three-calibration or three-calibration-one experiment.
In the negative step calibration device, the pressure sensors are all piezoelectric pressure sensors. The piezoelectric pressure sensor is excited by changing carbon dioxide heat absorption into gas to rupture a membrane and generate a negative step pressure signal. Because of the characteristics of the piezoelectric crystal, the charge generated by static pressure is easy to leak, so the piezoelectric sensor is not sensitive to the static pressure, and no matter whether the piezoelectric crystal is pressed or not, the pressure is large or small, no signal is output, so the piezoelectric sensor can not be used for static measurement and only can measure the dynamic pressure.
According to the negative step calibration device, the sealing gasket is arranged between the upper cover and the cavity and plays a sealing role.
The negative step calibration device is characterized in that the diaphragm pressing screw is provided with external threads, the diaphragm pressing screw is in threaded connection with the stepped pressure relief opening, the valve core is provided with external threads, and the valve core is in threaded connection with the stepped through hole.
According to the negative step calibration device, the valve core is provided with the O-shaped ring, and the O-shaped ring plays a sealing role.
The negative step calibration device can generate different negative step signals by changing the thickness of the diaphragm and the amount of carbon dioxide filled in the device, so that the calibration of the pressure sensor is beneficial, and meanwhile, the experimental control can effectively protect the experimental device and the experimental environment.
The invention has the advantages that: 1. the calibrated sensor and the high-precision sensor are installed in the same environment, so that the pressures of the calibrated sensor and the high-precision sensor are consistent, and the calibration precision and the test precision are improved; 2. different negative step signals can be generated by changing the thickness of the diaphragm and the amount of carbon dioxide filled in the device, so that the calibration of the pressure sensor is beneficial, and meanwhile, the experimental control can effectively protect the experimental device and the experimental environment; 3. the sensor is calibrated by adopting the principle that a negative step pressure signal is generated when solid or liquid carbon dioxide absorbs heat and is changed into gas to break the membrane, the chemical property of the carbon dioxide is inert, the heat absorption efficiency is high, the heat absorption reaction is rapid, the success rate of the membrane breaking experiment is extremely high, the signal generating the negative step is good, and the design of a calibration device is reasonable; 4. the experimental cost is low, the device is simple, the operation is simple and convenient, no pollution is caused, and the experimental effect is good; 5. the negative step calibration effect on the pressure sensor is good, and meanwhile, the process of calibrating the pressure sensor in a high-pressure environment is also included; 6. the design of the V-shaped groove of the diaphragm pressing screw is a bright point, the V-shaped groove can enable the extruded part of the diaphragm to generate local stress concentration after pressing the diaphragm, the diaphragm can be easily cut and broken after bearing internal high pressure, the diaphragm part cut during breaking can be blown out completely instead of puncturing the diaphragm into small holes in a blooming shape, and therefore carbon dioxide gas can be blown out rapidly in a large amount in the moment to generate a good negative step pressure signal.
The device is reasonable and suitable for laboratory operation, carbon dioxide is easy to obtain and safe, no pollution is caused, and negative step calibration of the pressure sensor is realized by the principle that a negative step pressure signal is generated when solid or liquid carbon dioxide absorbs heat and is changed into gas to rupture a membrane.
Drawings
FIG. 1 is a schematic structural diagram of the present invention.
Fig. 2 is a schematic structural diagram of a diaphragm pressing screw with a special shape design.
In the figure: 1-a pressure sensor, 2-an upper cover, 3-a sealing gasket, 4-a bolt, 5-a cavity, 6-an electrode, 7-a pressure relief opening, 8-a diaphragm, 9-a diaphragm pressing screw, 10-an electric heating wire, 11-a bracket, 12-a filling opening, 13-a valve core, 14-an O-shaped ring, 15-solid or liquid carbon dioxide and 16-a V-shaped groove.
Detailed Description
As shown in fig. 1 and 2, a negative step calibration device comprises an upper cover 2, a sealing gasket 3, a bolt 4, a cavity 5, an electrode 6, a pressure relief port 7, a diaphragm 8, a diaphragm pressing screw 9, an electric heating wire 10, a bracket 11, a filling port 12, a valve core 13, an O-ring 14, and solid or liquid carbon dioxide 15. The upper cover 2 may mount four pressure sensors in a circumferential shape. The upper cover 2 is connected with the cavity 5 through a bolt 4, and a sealing gasket 3 is arranged between the upper cover 2 and the cavity 5 for sealing. One side of the cavity 5 is provided with an electrode 6 which passes through, and the two electrodes 6 are connected by an electric heating wire 10 in the device; the other side wall of the cavity 5 is provided with a step-shaped through hole and a carbon dioxide filling opening 12, the through hole with the small middle caliber of the step-shaped through hole is directly communicated with the inside of the cavity 5, the carbon dioxide filling opening 12 is communicated with the through hole with the large middle caliber of the step-shaped through hole, a valve core 13 is arranged in the through hole with the large middle caliber of the step-shaped through hole to plug the through hole, the bottom of the cavity 5 is provided with a step-shaped pressure relief opening 7, the pressure relief opening with the small middle caliber of the step-shaped pressure relief opening 7 is directly communicated with the inside of the cavity 5, a membrane 8 is arranged in the pressure relief opening with. The diaphragm pressing screw 9 adopts a large-diameter through design and a V-shaped groove 16 design.
a. A brittle metal diaphragm 8 is arranged at the pressure relief opening 7 and is fixed by a diaphragm pressing screw 9. At the moment, the upper cover 2, the cavity 5 and the brittle metal film 8 at the pressure relief opening 7 enclose a closed empty chamber together. Filling solid or liquid carbon dioxide 15 into the empty chamber, wherein if the carbon dioxide 15 is solid, the filling process comprises the following steps: opening the upper cover 2, closing the valve core 13, putting solid carbon dioxide into the cavity, then covering the upper cover 2, screwing the bolt 4, and sealing the space between the upper cover 2 and the cavity 5 by the sealing gasket 3; if the carbon dioxide 15 is in liquid state, the filling process is as follows: and opening the valve core 13, filling liquid carbon dioxide into the closed empty chamber through the filling port 12, closing the valve core 13 after filling, and arranging an O-shaped ring 14 on the inner side of the valve core 13, wherein the O-shaped ring 14 plays a role in sealing. After the high-precision sensor and the calibrated sensor are installed, the two electrodes 6 are electrified, the electric heating wire 10 gradually heats and heats the solid or liquid carbon dioxide 15 in the device to gradually change the solid or liquid carbon dioxide into gas. The pressure in the device will gradually increase to a high level before the carbon dioxide gas breaks the membrane. Therefore, the invention can calibrate the pressure sensor under high pressure environment.
b. The diaphragm 8 is broken instantly when the pressure of the carbon dioxide gas in the device is increased to exceed the bearable ultimate strength, and the carbon dioxide gas escapes through the pressure relief opening 7 and the through part of the diaphragm pressing screw 9. The diaphragm pressing screw 9 is designed by adopting a V-shaped groove 16, the inner edge of the diaphragm pressing screw is 0.2-0.5mm higher than the outer edge of the diaphragm pressing screw, the diaphragm 8 can generate local stress concentration at the extruded part acted with the V-shaped groove 16, the diaphragm can be broken easily after bearing the internal high pressure, and the diaphragm 8 part can be knocked down by the whole body in the process of breaking the diaphragm instead of puncturing the diaphragm into small holes in a flower shape, so that the instant large-amount rapid burst of carbon dioxide gas is facilitated; the diaphragm pressure screw 9 is designed to be a large-diameter through hole, the through hole is as large as the opening of the pressure relief opening 7, and the design is also designed to enable high-pressure carbon dioxide gas for breaking the diaphragm to escape in a large amount instantly, so that the generated negative step pressure signal has a steep back edge, abundant frequency signals are generated, and a good negative step calibration effect can be achieved.
Claims (10)
1. A negative step calibration device is characterized by comprising a cavity (5), wherein a mounting through hole for mounting a pressure sensor (1) is arranged above the cavity (5), one side wall of the cavity (5) is provided with two electrode through holes, two electrodes (6) respectively penetrate through the side wall of the cavity (5) through one electrode through hole and enter the cavity (5), the electrodes (6) are insulated from the cavity (5), and the two electrodes (6) are connected with an electric heating wire (10) between the end parts of the cavity (5) inside; the other side wall of the cavity (5) is provided with a step-shaped through hole and a carbon dioxide filling opening (12), the through hole with the small middle caliber of the step-shaped through hole is directly communicated with the inside of the cavity (5), the carbon dioxide filling opening (12) is communicated with the through hole with the large middle caliber of the step-shaped through hole, a valve core (13) is arranged in the through hole with the large middle caliber of the step-shaped through hole to plug the through hole, the bottom of the cavity (5) is provided with a step-shaped pressure relief opening (7), the pressure relief opening with the small middle caliber of the step-shaped pressure relief opening (7) is directly communicated with the inside of the cavity (5), a membrane (8) is arranged in the pressure relief opening with the large middle caliber of the step-shaped pressure relief opening (7) and.
2. A negative step change calibrating device according to claim 1, wherein the aperture of the through hole in the diaphragm pressure screw is as large as the aperture of the pressure relief vent having a smaller aperture of the stepped pressure relief vent (7).
3. A negative step change calibrating device according to claim 2, characterized in that the upper end surface of the diaphragm pressing screw (9) is designed to be a V-shaped groove (16), the inner edge of the V-shaped groove (16) is higher than the outer edge by 0.2-0.5mm, and the inner edge of the V-shaped groove (16) contacts the diaphragm (8).
4. The negative step calibration device according to claim 3, wherein the cavity (5) is opened at the upper part, the upper cover (2) is mounted at the opening at the upper part of the cavity (5) through the bolt (4), and the mounting through hole is arranged on the upper cover (2).
5. A negative step calibration device according to claim 4, wherein 4 pressure sensors (1) are uniformly arranged on the upper cover (2) in a circumferential shape: the device comprises a high-precision sensor, three calibrated sensors or three high-precision sensors and one calibrated sensor, and achieves the purpose of one-calibration three-calibration or three-calibration-one experiment.
6. A negative step calibration device according to claim 5, wherein the pressure sensors (1) are all piezoelectric pressure sensors.
7. A negative step calibration device according to claim 4, 5 or 6, wherein a sealing gasket (3) is arranged between the upper cover (2) and the chamber (5), and the sealing gasket (3) is used for sealing.
8. The negative step calibration device according to claim 1, 2, 3, 4, 5 or 6, wherein the diaphragm pressure screw (9) has external threads, the diaphragm pressure screw (9) is in threaded connection with the stepped pressure relief port (7), the valve core (13) has external threads, and the valve core (13) is in threaded connection with the stepped through hole.
9. A negative step calibration device according to claim 1 or 2 or 3 or 4 or 5 or 6, wherein the valve member (13) is provided with an O-ring (14), the O-ring (14) providing a sealing function.
10. A negative step calibration device according to claim 4, 5 or 6 wherein the pressure sensor is calibrated by varying the thickness of the diaphragm and the amount of carbon dioxide filled in the device to produce different negative step signals.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911084693.6A CN111220322B (en) | 2019-11-08 | 2019-11-08 | Negative step calibrating device |
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| CN201911084693.6A CN111220322B (en) | 2019-11-08 | 2019-11-08 | Negative step calibrating device |
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| CN111220322A true CN111220322A (en) | 2020-06-02 |
| CN111220322B CN111220322B (en) | 2021-04-09 |
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| CN201911084693.6A Expired - Fee Related CN111220322B (en) | 2019-11-08 | 2019-11-08 | Negative step calibrating device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114518193A (en) * | 2022-01-27 | 2022-05-20 | 中国航空工业集团公司北京长城计量测试技术研究所 | Non-resonant negative step pressure calibration device |
| CN114754925A (en) * | 2022-01-27 | 2022-07-15 | 中国航空工业集团公司北京长城计量测试技术研究所 | Portable negative step pressure generator |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101788366A (en) * | 2010-01-15 | 2010-07-28 | 北京航空航天大学 | Positive/negative pressure signal generating device |
| CN103728095A (en) * | 2014-01-10 | 2014-04-16 | 浙江大学 | Negative step force testing system |
| CN103759873A (en) * | 2014-01-10 | 2014-04-30 | 浙江大学 | Negative step force testing system |
| CN105333993A (en) * | 2015-11-18 | 2016-02-17 | 北京理工大学 | Micro-force sensor dynamic calibration system and method based on micro negative step force |
| CN106768626A (en) * | 2016-12-03 | 2017-05-31 | 中国航空工业集团公司北京长城计量测试技术研究所 | A kind of gas Step Pressure signal generator |
| CN109946020A (en) * | 2019-02-23 | 2019-06-28 | 山东大学 | A kind of test of rapidity pressure sensor dynamic and calibrating installation |
-
2019
- 2019-11-08 CN CN201911084693.6A patent/CN111220322B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101788366A (en) * | 2010-01-15 | 2010-07-28 | 北京航空航天大学 | Positive/negative pressure signal generating device |
| CN103728095A (en) * | 2014-01-10 | 2014-04-16 | 浙江大学 | Negative step force testing system |
| CN103759873A (en) * | 2014-01-10 | 2014-04-30 | 浙江大学 | Negative step force testing system |
| CN105333993A (en) * | 2015-11-18 | 2016-02-17 | 北京理工大学 | Micro-force sensor dynamic calibration system and method based on micro negative step force |
| CN106768626A (en) * | 2016-12-03 | 2017-05-31 | 中国航空工业集团公司北京长城计量测试技术研究所 | A kind of gas Step Pressure signal generator |
| CN109946020A (en) * | 2019-02-23 | 2019-06-28 | 山东大学 | A kind of test of rapidity pressure sensor dynamic and calibrating installation |
Non-Patent Citations (2)
| Title |
|---|
| 张瑜 等: "基于环境因子的火炮膛压测试仪校准装置", 《探测与控制学报》 * |
| 魏燕定: "标准负阶跃力的实现及其测量研究", 《实验力学》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114518193A (en) * | 2022-01-27 | 2022-05-20 | 中国航空工业集团公司北京长城计量测试技术研究所 | Non-resonant negative step pressure calibration device |
| CN114754925A (en) * | 2022-01-27 | 2022-07-15 | 中国航空工业集团公司北京长城计量测试技术研究所 | Portable negative step pressure generator |
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