CN111060251A - Automatic detection and calibration device and method for flexible pressure sensor - Google Patents
Automatic detection and calibration device and method for flexible pressure sensor Download PDFInfo
- Publication number
- CN111060251A CN111060251A CN201911420428.0A CN201911420428A CN111060251A CN 111060251 A CN111060251 A CN 111060251A CN 201911420428 A CN201911420428 A CN 201911420428A CN 111060251 A CN111060251 A CN 111060251A
- Authority
- CN
- China
- Prior art keywords
- pressure sensor
- flexible pressure
- flexible
- flat plate
- air bag
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- 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
-
- 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
Abstract
The invention belongs to the field of automation equipment, and particularly relates to an automatic detection and calibration device and method for a flexible pressure sensor. Flexible pressure sensor automated inspection calibration device includes: the lower flat plate is vertically provided with a plurality of guide columns, the guide columns are provided with limiting blocks, and the soft air bags can contact the lower flat plate and apply certain pressure to the lower flat plate after being inflated. The flexible pressure sensor module is placed on the lower flat plate, and a plurality of flexible pressure sensors to be tested and calibrated are electrically connected with the measuring system through the circuit board; the measurement module includes: signal receiving unit, signal processing unit, data management unit. The flexible pressure sensor rapid inflation device rapidly inflates the flexible air bag through the air source, applies uniform pressure to the surfaces of the plurality of flexible pressure sensors, realizes large-area, rapid, high-consistency, visual and full-range pressure automatic measurement and calibration, and is very suitable for factory detection and calibration of industrial mass production of the flexible pressure sensors.
Description
Technical Field
The invention belongs to the field of automation equipment, and particularly relates to an automatic detection and calibration device and method for a flexible pressure sensor.
Background
The flexible/organic electronic technology based on the flexible organic/inorganic material electronic device and the ductile substrate is an emerging leading-edge electronic technology, and the flexible electronic has huge application prospects in the fields of internet of things, intelligent wearing, consumer electronics, medical health, human-computer interaction, industry 4.0, intelligent home furnishing and the like due to the unique flexibility/ductility and the efficient and low-cost manufacturing process. Due to the hysteresis characteristic of a flexible material in the flexible electronic device, the precision of the flexible pressure sensor can be influenced to a certain degree, and in order to improve the measurement precision in the use process, the flexible pressure sensor needs to be tested and calibrated before leaving a factory.
At present, the conventional pressure measurement calibration device (such as a handheld pressure gauge, a piston type force meter, a standard weight and the like) is low in measurement speed and poor in consistency, and the test and calibration requirements of a large-area, flexible, ultrathin and multipoint flexible pressure sensor are difficult to meet.
Disclosure of Invention
The invention aims to overcome the technical problems in the conventional pressure measurement calibration device, provides the automatic detection calibration device and method for the flexible pressure sensor, which can realize large-area, quick and accurate multipoint consistency detection simultaneously and has the function of automatic pressure measurement calibration of full-range pressure.
The technical scheme adopted by the invention for solving the technical problems is as follows:
the utility model provides a flexible pressure sensor automated inspection calibration device which characterized in that: comprises a mechanical device module, a flexible pressure sensor module and a measuring module,
the mechanical device module includes: the air bag type air bag comprises a lower flat plate, an upper flat plate and a soft air bag capable of being inflated and deflated, wherein a plurality of guide columns are vertically arranged on the lower flat plate, limiting blocks are arranged on the guide columns, and the upper flat plate provided with guide holes penetrates through the guide columns and is arranged between the lower flat plate and the limiting blocks; the inflatable and deflatable soft air bag is arranged between the lower flat plate and the upper flat plate and is fixed on the lower surface of the upper flat plate, the soft air bag can contact the lower flat plate after being inflated and applies certain pressure to the lower flat plate, and the soft air bag is provided with an air inlet, an air release port, a pressure gauge and/or a pressure sensor; the air inlet is also provided with an air source and a switch valve, and the air outlet is also provided with a switch valve;
a flexible pressure sensor module is placed on the lower plate, comprising: the flexible pressure sensor is fixed on the supporting plate, the supporting plate and the circuit board are positioned through a positioning hole, and each flexible pressure sensor is electrically connected with a measuring system through the circuit board;
the measurement module includes: the flexible pressure sensor comprises a signal receiving unit for receiving pressure signals of the flexible pressure sensor, a signal processing unit for processing the received pressure signals, and a data management unit for recording and managing the acquired signal data.
Further, a pressure regulating valve is arranged between the air source and the switch valve at the air inlet.
Furthermore, the upper end of the guide post is provided with an external thread, the limiting block is a flange nut, the flange edge of the flange nut is arranged in the clamping groove of the upper flat plate, and the internal thread of the flange nut is screwed with the external thread of the guide post to limit the position of the upper flat plate.
Furthermore, the guide post is a polished rod, the limiting block is a fixed sleeve with an open conical external thread, the fixed sleeve is screwed with a screwing sleeve with a conical internal thread, the screwing sleeve rotates downwards to enable the fixed sleeve to be fixed with the guide post, and the fixed sleeve is fixedly connected with the upper flat plate.
Further, the circuit board is a PCB circuit board or an FPC circuit board.
Further, the lower surface of the upper flat plate is provided with an inner concave part to limit the play of the soft air bag.
Furthermore, the upper flat plate and the lower flat plate are made of acrylic materials or aluminum alloy materials.
A method for calibrating a flexible sensor by using an automatic detection calibration device of the flexible pressure sensor is characterized in that: placing a flexible pressure sensor in a flexible pressure sensor module, placing the flexible pressure sensor module between a flexible air bag and a lower flat plate, wherein the flexible pressure sensor faces upwards and a circuit board faces downwards when the flexible pressure sensor module is placed in the flexible air bag, and electrically connecting the circuit board with a measuring module;
setting a calibration pressure value, opening an air source and a first switch valve, inflating a soft air bag, detecting a signal of a flexible pressure sensor by a signal receiving unit in a measuring module, and processing the received pressure signal by a signal processing unit; the data management unit records and manages the acquired data; by repeatedly inflating and deflating the soft air bag, the stress of the pressure sensitive units in the flexible pressure sensors tends to be balanced, and the measuring module automatically creates a calibration coefficient and applies the calibration coefficient to each single flexible pressure sensor.
The automatic detection and calibration device and method for the flexible pressure sensor have the beneficial effects that:
1. the soft air bag is quickly inflated by the air source, uniform pressure can be applied to the surfaces of all the sensing units, and the automatic pressure measurement and calibration within the full-range of the pressure sensor can be realized in a large area, quickly and accurately and digitally/visually detected and calibrated by simultaneously ensuring multipoint consistency.
2. Through rapid measurement calibration, resistance value data of each sensing unit can be measured, and the force and the pressure intensity acting on the flexible pressure sensor, the time and the position can be obtained through a simple calibration function.
3. The device is simple to operate, accurate and reliable in measured data, capable of displaying in real time, has the functions of measurement, calibration and data analysis, and is very suitable for the industrial mass production field detection and calibration of the flexible pressure sensor.
Drawings
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
FIG. 1 is a general view of an apparatus according to an embodiment of the present invention;
FIG. 2 is a block diagram of a flexible pressure sensor module according to an embodiment of the invention;
FIG. 3 is a block diagram of a second embodiment of a limiting block of the present invention;
FIG. 4 is a schematic view of a pneumatic system according to an embodiment of the present invention;
FIG. 5 is a schematic view of a measurement system according to an embodiment of the present invention.
In the figure, 11, a lower flat plate, 12, an upper flat plate, 13, a flexible air bag, 131, a pressure gauge, 132, an air inlet, 133, an air release port, 134, an air source, 135, a first switch valve, 136, a pressure regulating valve, 137, a second switch valve, 14, a guide pillar, 15, a flange nut, 16, a fixing sleeve, 17, a screwing sleeve, 2, a flexible pressure sensor module, 21, a flexible pressure sensor, 22, a supporting plate, 23, a circuit board, 3, a measuring module, 31, a signal receiving unit, 32, a signal processing unit, 33 and a data management unit.
Detailed Description
The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic views illustrating only the basic structure of the present invention in a schematic manner, and thus show only the constitution related to the present invention.
Fig. 1-5 show an embodiment of an automatic detection calibration device for a flexible pressure sensor according to the present invention. As shown in fig. 1, the present embodiment includes a mechanical device module, a flexible pressure sensor module 2, and a measurement module 3, where the mechanical device module further includes: the air bag type air bag comprises a lower flat plate 11, an upper flat plate 12 and an inflatable and deflatable soft air bag 13, wherein a plurality of guide posts 14 are vertically arranged on the lower flat plate 11, limiting blocks are arranged on the guide posts 14, corresponding guide holes are arranged on the upper flat plate 12, and the guide holes of the upper flat plate 12 penetrate through the guide posts 14. The upper end of the guide post 14 is provided with a limiting block, which is used for limiting and adjusting the distance between the upper flat plate 12 and the lower flat plate 11. The position of the limiting block on the guide post 14 is adjustable, and in fig. 1, as a first embodiment, the limiting block is in the form of a flange nut 15, the internal thread of the flange nut 15 is matched with the external thread on the guide post 14 for positioning, and the flange edge of the flange nut 15 is clamped in the clamping groove of the upper plate 12. As the nut rotates, the flange moves the upper plate 12 over the guide posts 14.
Fig. 3 shows a second embodiment of the limiting block, in this embodiment, the guide post 14 is a polish rod, the limiting block is a fixed sleeve 16 with an open conical external thread, and the inner hole of the fixed sleeve 16 is slightly larger than the diameter of the guide post 14 and can move smoothly on the guide post 14. The rotating sleeve 17 has a tapered internal thread that mates with the thread of the fixed sleeve 16, allowing the internal bore of the fixed sleeve 16 to contract and tightly secure the guide post 14 when the rotating sleeve 17 is rotated downward.
As shown in fig. 1, the soft air bag 13 is disposed between the lower plate 11 and the upper plate 12 and fixed on the lower surface of the upper plate 12, the soft air bag 13 is inflated to expand, and the lower portion can contact the lower plate 11 and apply a certain pressure to the lower plate 11 and the flexible pressure sensor module 2.
As shown in fig. 2, the flexible pressure sensor module 2 is placed on the lower plate 11, and includes: a supporting plate 22, a circuit board 23 and a plurality of flexible pressure sensors 21 to be tested and calibrated. The flexible pressure sensors 21 are fixed on the supporting plate 22, the supporting plate 22 and the circuit board 23 are positioned through the positioning holes, and each flexible pressure sensor 21 is electrically connected with the measuring module 3 through the circuit board 23. The flexible pressure sensors 21 can be electrically connected with the circuit board 23 through the positioning of the supporting plate 22, so that large-scale verification can be realized. The circuit board 23 may be a PCB circuit board or an FPC circuit board.
As shown in the schematic view of the pneumatic system in fig. 4, the flexible air bag 13 is provided with an air inlet 132, an air outlet 133 and a pressure gauge 131. The air inlet 132 is further provided with an air source 134 and a first switch valve 135, the air source 134 can inflate the flexible air bag 13 to rapidly expand, and then the flexible pressure sensor 21 is detected and calibrated. In order to regulate the air pressure of the air source 134, a pressure regulating valve 136 is added after the air source 134, and the maximum working pressure of the air bag can be controlled by setting the pressure regulating valve 136. A second on-off valve 137 is further provided at the relief port 133. The first opening/closing valve 135 and the second opening/closing valve 137 may be manual valves or electric valves, preferably electric valves. When the soft air bag 13 is inflated, the first switch valve 135 is opened, and the second switch valve 137 is closed. When the inflation reaches the maximum pressure range, the first switch valve 135 is closed, the second switch valve 137 is opened intermittently, the pressure is reduced after the second switch valve 137 is opened, and the tests under different pressures can be carried out.
As shown in fig. 5, the measurement module 3 includes: signal receiving section 31, signal processing section 32, and data management section 33. The measurement module 3 collects data of the pressure gauge 131 and the flexible pressure sensor 21, processes the data, and writes calibration parameters into the flexible pressure sensor 21. The measurement module 3 has the functions of storing original calibration data of the flexible pressure sensor, importing and exporting data, calculating a calibration coefficient, analyzing data, displaying a curve and the like.
When the measurement calibration is carried out, the flexible pressure sensor 21 is placed in the flexible pressure sensor module 2, the flexible pressure sensor module 2 is placed between the air bag and the lower flat plate 11, the flexible pressure sensor 21 faces upwards when the flexible pressure sensor module is placed in the air bag, the circuit board 23 faces downwards, and the circuit board 23 is electrically connected with the measurement module 3. Setting a calibrated pressure value, opening an air source 134 and a first switch valve 135, inflating the soft air bag 13 through the air inlet 132, applying a uniform pressure on the surface of the sensor by the soft air bag 13 along with the continuous increase of the pressure of the soft air bag 13, and calculating the pressure applied on the surface of the sensor by using a formula F ═ PS, (F is the pressure applied on the sensor, P is the pressure of the air bag displayed on the pressure gauge 131, and S is the area of a pressure sensitive area of the sensor), wherein the change of the pressure can be seen and quantified on the software of the measuring module 3. The signal receiving unit 31 in the measuring module 3 detects the signal of the flexible pressure sensor 21 and processes the received pressure signal through the signal processing unit 32; the data management unit 33 records and manages the acquired data. By repeatedly inflating and deflating the flexible air bag 13, the stress of each pressure sensitive unit tends to be balanced, and in the balancing process, the measuring module 3 automatically creates a calibration coefficient and applies the calibration coefficient to each individual flexible pressure sensor 21 to compensate the weak uneven output among the single sensing units, so that the precision, the consistency and the speed of each flexible pressure sensor 21 are improved.
In order to limit the play of the soft air bag 13, a concave part is arranged on the lower surface of the upper flat plate 12, and the soft air bag 13 is limited by the edge of the concave part, so that the pressure can be better applied to the lower flat plate 11.
In order to make the upper plate 12 and the lower plate 11 lighter, thinner and more rigid, an acrylic material or an aluminum alloy material is preferably used.
It should be understood that the above-described specific embodiments are merely illustrative of the present invention and are not intended to limit the present invention. Obvious variations or modifications which are within the spirit of the invention are possible within the scope of the invention.
Claims (10)
1. The utility model provides a flexible pressure sensor automated inspection calibration device which characterized in that: the method comprises the following steps: the device comprises a mechanical device module, a flexible pressure sensor module (2) and a measuring module (3);
the mechanical device module includes: the device comprises a lower flat plate (11), an upper flat plate (12) and a flexible air bag (13) capable of being inflated and deflated, wherein a plurality of guide columns (14) are vertically arranged on the lower flat plate (11), and limiting blocks are arranged on the guide columns (14); the upper flat plate (12) provided with a guide hole penetrates through a guide post (14) and is arranged between the lower flat plate (11) and the limiting block; the inflatable and deflatable flexible air bag (13) is arranged between the lower flat plate (11) and the upper flat plate (12) and is fixed on the lower surface of the upper flat plate (12), the flexible air bag (13) can contact the lower flat plate (11) after being inflated and applies certain pressure to the lower flat plate (11), and an air inlet (132), an air release port (133) and a pressure gauge (131) are arranged on the flexible air bag (13); an air source (134) and a first switch valve (135) are further arranged at the air inlet (132), and a second switch valve (137) is further arranged at the air release port (133);
a flexible pressure sensor module (2) is placed on the lower plate (11) comprising: the flexible pressure sensor testing device comprises a supporting plate (22), a circuit board (23) and a plurality of flexible pressure sensors (21) to be tested and calibrated, wherein the flexible pressure sensors (21) are fixed on the supporting plate (22), the supporting plate (22) and the circuit board (23) are positioned through positioning holes, and each flexible pressure sensor (21) is electrically connected with a measuring module (3) through the circuit board (23);
the measurement module (3) comprises: the pressure sensor comprises a signal receiving unit (31) for receiving pressure signals of the flexible pressure sensor (21), a signal processing unit (31) for processing the received pressure signals, and a data management unit (33) for recording and managing the collected pressure signal data.
2. The automatic detection and calibration device of the flexible pressure sensor according to claim 1, wherein: and a pressure regulating valve (136) is also arranged between the air source (134) and the first switch valve (135).
3. The automatic detection and calibration device of the flexible pressure sensor according to claim 1, wherein: the upper end of the guide post (14) is provided with external threads, the limiting block is a flange nut (15), the flange edge of the flange nut (15) is installed in the clamping groove of the upper flat plate (12), and the internal threads of the flange nut (15) are screwed with the external threads of the guide post (14) to limit the position of the upper flat plate (12).
4. The automatic detection and calibration device of the flexible pressure sensor according to claim 1, wherein: the guide post (14) is a polished rod, the limiting block is a fixing sleeve (16) with an open conical external thread, the fixing sleeve (16) is screwed with a screwing sleeve (17) with a conical internal thread, the screwing sleeve (17) rotates downwards to enable the fixing sleeve (16) to be fixed with the guide post (14), and the fixing sleeve (16) is fixedly connected with the upper flat plate (12).
5. The automatic detection and calibration device of the flexible pressure sensor as claimed in claim 4, wherein: the lower surface of the upper flat plate (12) is provided with an inner concave part to limit the play of the soft air bag (13).
6. The automatic detection and calibration device of the flexible pressure sensor according to claim 1, wherein: the circuit board (23) is a PCB circuit board or an FPC circuit board.
7. The automatic detection and calibration device of the flexible pressure sensor according to claim 1, wherein: the first switch valve (135) and the second switch valve (137) are electric switch valves.
8. The automatic detection and calibration device of the flexible pressure sensor according to any one of claims 1 to 7, wherein: the upper flat plate (12) is made of an acrylic material or an aluminum alloy material.
9. The automatic detection and calibration device of the flexible pressure sensor according to any one of claims 1 to 7, wherein: the lower flat plate (11) is made of an acrylic material or an aluminum alloy material.
10. The method for calibrating a flexible sensor by using the automatic detection and calibration device for the flexible pressure sensor as claimed in claim 1, wherein: the flexible pressure sensor (21) is placed in the flexible pressure sensor module (2), the flexible pressure sensor module (2) is placed between the flexible air bag (13) and the lower flat plate (11), the flexible pressure sensor (21) faces upwards and the circuit board (23) faces downwards when the flexible pressure sensor module is placed in the flexible air bag, and the circuit board (23) is electrically connected with the measuring module (3);
setting a calibrated pressure value, opening an air source (134) and a first switch valve (135), inflating a soft air bag (13), detecting a signal of a flexible pressure sensor (21) by a signal receiving unit (31) in a measuring module (3), and processing the received pressure signal by a signal processing unit (32); the data management unit (33) records and manages the acquired data; by repeatedly inflating and deflating the soft air bag (13), the stress of the pressure sensitive units in the flexible pressure sensors (21) tends to be balanced, and the measuring module (3) automatically creates a calibration coefficient and applies the calibration coefficient to each individual flexible pressure sensor (21).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911420428.0A CN111060251A (en) | 2019-12-31 | 2019-12-31 | Automatic detection and calibration device and method for flexible pressure sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911420428.0A CN111060251A (en) | 2019-12-31 | 2019-12-31 | Automatic detection and calibration device and method for flexible pressure sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111060251A true CN111060251A (en) | 2020-04-24 |
Family
ID=70305979
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911420428.0A Pending CN111060251A (en) | 2019-12-31 | 2019-12-31 | Automatic detection and calibration device and method for flexible pressure sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111060251A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112539877A (en) * | 2020-12-24 | 2021-03-23 | 广电计量检测（重庆）有限公司 | Distributed flexible pressure sensor calibration equipment and method |
| CN113654720A (en) * | 2021-09-02 | 2021-11-16 | 安徽中科本元信息科技有限公司 | Air pressure type flexible force-sensitive sensor calibration device and calibration method |
-
2019
- 2019-12-31 CN CN201911420428.0A patent/CN111060251A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112539877A (en) * | 2020-12-24 | 2021-03-23 | 广电计量检测（重庆）有限公司 | Distributed flexible pressure sensor calibration equipment and method |
| CN113654720A (en) * | 2021-09-02 | 2021-11-16 | 安徽中科本元信息科技有限公司 | Air pressure type flexible force-sensitive sensor calibration device and calibration method |
| CN113654720B (en) * | 2021-09-02 | 2023-11-17 | 安徽中科本元信息科技有限公司 | Pneumatic flexible force sensor calibration device and calibration method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111060251A (en) | Automatic detection and calibration device and method for flexible pressure sensor | |
| US9429493B2 (en) | Manifold assembly for a portable leak tester | |
| CN206974611U (en) | The positive and negative two-way caliberating device of pressure sensor | |
| CN112284629B (en) | Air tightness testing device and testing method | |
| CN101666726B (en) | Piston pressure-regulating high-sensitivity small-tension film-shaped biomaterial mechanic detector | |
| CN109708810A (en) | A kind of apparatus and system for film tactile sensing chip testing | |
| CN110608953A (en) | Triaxial test soil unit central position pore water pressure test system | |
| CN209745468U (en) | device for testing film touch sensing chip | |
| CN113654720B (en) | Pneumatic flexible force sensor calibration device and calibration method | |
| CN201514229U (en) | Vortex flow sensor check table | |
| CN211061113U (en) | Automatic detection and calibration device for flexible pressure sensor | |
| CN201016701Y (en) | Apparatus for measuring thickness of battery | |
| CN107192620A (en) | A kind of wood plastic composite creep test device | |
| CN206740292U (en) | A kind of residual stress detects strain rosette | |
| CN215573555U (en) | Flexible pressure sensor calibration experimental device | |
| CN205808899U (en) | A kind of crystal silicon solar batteries sheet welding peel strength multi-channel detection instrument | |
| CN114993890A (en) | Particle medium contact force chain network test device | |
| CN206974597U (en) | Match somebody with somebody parallel screw mandrel baroceptor caliberating device outside a kind of | |
| CN112881179A (en) | Soil body tester based on soil body elasticity test and test method thereof | |
| CN108152061A (en) | side window pressure detecting system and method | |
| CN106679927B (en) | Air resistance coefficient tester constructed by small wind tunnel | |
| CN207336298U (en) | Viscosity measurements sensor based on the coupling of double piezoelectricity | |
| CN218381417U (en) | Dynamometer calibrating device | |
| CN110702307A (en) | Method for testing pressure parameters of multi-channel sensor | |
| CN212479831U (en) | Surface strain gauge pasting and mounting device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB03 | Change of inventor or designer information | ||
| CB03 | Change of inventor or designer information |
Inventor after: Xiong Zuoping Inventor after: Wang Yukang Inventor after: Fan Longfei Inventor after: Zhou Zhen Inventor before: Xiong Zuoping Inventor before: Wang Yukang Inventor before: Fan Longfei Inventor before: Zhou Zhen Inventor before: Zhang Ting |