A device for detecting airbag pressure maintenance and a method for detecting airbag pressure maintenance

Abstract

The application discloses a device for detecting pressure maintaining of a safety air bag and a detection method thereof, and relates to the technical field of air bag detection. The device for detecting pressure maintaining of a safety air bag and the detection method thereof comprise a gas storage tank, an air bag and an air bag accommodating device. The gas storage tank is connected to the air bag through a gas path assembly and is used for inflating and maintaining pressure of the air bag or for explosion. The air bag accommodating device comprises a box body, blades and a pressure sensor one. The bottom of the box body is provided with a through hole for matching the pipeline assembly. The inside of the box body is provided with a groove for placing the air bag. The top of the box body is provided with an opening. The top of the box body is provided with a plurality of blades for forming resistance to the air bag. The inner wall of the blade is provided with the pressure sensor one. The application can realize a detection device and a testing method combining static simulation and dynamic simulation of the safety air bag. The device is simple, convenient to operate and can simulate the use state of the air bag.

Description

Technical Field

[0001] This invention relates to the field of airbag testing technology, and in particular to a device and method for testing the pressure retention of a safety airbag. Background Technology

[0002] An airbag is a passive safety protection system that works in conjunction with seat belts to provide effective collision protection for passengers. In a car collision, airbags can reduce head injuries by about 25% and facial injuries by about 80%. The quality of airbags is crucial to the safety of drivers and passengers. Their working principle is as follows: when a collision occurs, the gas generator inside the airbag rapidly produces a large amount of gas, causing the airbag to inflate and deploy. This, combined with the seat belt, reduces passenger injury. However, during this process, the stiffness of the frontal airbag, i.e., the magnitude and changes in the internal pressure, can affect the degree of injury suffered by the passenger.

[0003] The existing method for testing airbag pressure is the Tank test, which is primarily a single test of the gas generator. This involves bursting the gas generator within a sealed container of a specified volume and then measuring the pressure change over time to obtain a Pt curve. However, this method cannot test the dynamic pressure of the airbag in dynamic system simulation tests. Therefore, to better measure the airbag deployment time in automotive dynamic simulation tests, we need to propose a pressure-holding testing device and method that combines static and dynamic simulations of airbags, thereby simulating actual airbag usage and overcoming the shortcomings of existing technologies. Summary of the Invention

[0004] The main objective of this invention is to provide a device and method for detecting the pressure of an airbag. The device is simple to use and easy to operate, and can effectively solve the technical problems in the background art.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a device and method for detecting the pressure holding of an airbag, comprising an air tank, an airbag and an airbag placement device. The air tank is connected to the airbag through an air circuit assembly and is used to inflate and maintain the pressure of the airbag or to burst it. The airbag placement device comprises a box body, blades and a pressure sensor. The bottom of the box body is provided with a through hole for cooperating with the pipeline assembly. The inside of the box body is provided with a groove for placing the airbag. The top of the box body is provided with an opening, and the top of the box body is provided with multiple blades for generating resistance to the airbag. The inner wall of the blades is provided with a pressure sensor.

[0006] Furthermore, one end of the blade is rotatably connected to the box body via an arc-shaped connector, and multiple blades come together to form a hemispherical body for closing the opening.

[0007] Furthermore, the number of leaves mentioned above is four, six, or eight.

[0008] Furthermore, multiple pressure sensors are fixed on the blades to detect the air pressure inside the airbag.

[0009] Furthermore, the gas path assembly includes a gas pipe equipped with a pressure sensor, an electro-proportional valve for controlling gas pressure, pneumatic solenoid valves A and B for adjusting the gas flow direction, and normally closed solenoid valves A and B for adjusting the gas guidance in static and dynamic simulations. The gas path assembly includes an inflation and pressure-holding gas path and a rupture gas path. In the inflation and pressure-holding gas path, the gas tank, pneumatic solenoid valve B, electro-proportional valve, pneumatic solenoid valve A, normally closed solenoid valve A, and airbag are connected in sequence. In the rupture gas path, the gas tank, normally closed solenoid valve B, normally closed solenoid valve A, and airbag are connected in sequence.

[0010] Furthermore, the bottom of the aforementioned box is a sloping surface with an inclination angle of 45-60 degrees.

[0011] Preferably, a method for detecting the pressure holding of an airbag includes the following steps:

[0012] a1) Place the uninflated airbag inside the box and connect one end of the air circuit assembly to the airbag's inflation port through the through hole, and connect the other end of the air circuit assembly to the air tank.

[0013] b1) Pressure holding test: Open the air tank. Pneumatic solenoid valve B, electric proportional valve, pneumatic solenoid valve A, and normally closed solenoid valve A are in the open state. Gas reaches the airbag through the above-mentioned air circuit components, causing the airbag to inflate. The blades of the airbag placement device rotate and open synchronously with the expansion of the airbag. Pressure sensor 1 is fixed inside the blade and is always in close contact with the airbag to collect data in real time. Pressure sensor 2 collects data from the bottom of the airbag at fixed time intervals.

[0014] c1) Explosion test: Open the gas storage tank, open the normally closed solenoid valve A and normally closed solenoid valve B, and the gas reaches the airbag through the above-mentioned gas circuit components, causing the airbag to inflate. The blades on the outside of the airbag open and close with the expansion of the airbag. When the airbag is about to explode, pressure sensor 1 inside the blade collects data in real time, and pressure sensor 2 detects the pressure value of the airbag at fixed time intervals.

[0015] As a preferred option, pressure sensors for different blades can confirm the burst zone by detecting pressure values.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] Firstly, this invention provides a device for detecting airbag pressure holding, comprising an air tank and an airbag. The air tank is connected to the airbag via an air passage assembly for inflating and maintaining pressure or for the airbag to burst. It also includes an airbag placement device, which comprises a housing, blades, and a pressure sensor. The bottom of the housing has a through hole for accommodating the piping assembly, the interior of the housing has a groove for placing the airbag, and the top of the housing has an opening. The top of the housing has multiple blades for creating resistance to the airbag, and the inner wall of the blades is equipped with a pressure sensor. This device for detecting airbag pressure holding can achieve dynamic and static simulations of actual automotive airbags. The device is simple, easy to operate, and capable of multi-functional simulations.

[0018] Secondly, in this invention, one end of the blade is rotatably connected to the box body through an arc-shaped connector. After the four blades come together, they form an open hemispherical body for closing. The blades generate resistance to the airbag through their own weight and the friction between the arc-shaped connector and the box body, thereby simulating the resistance of an actual car airbag and making it closer to the actual use state of the airbag.

[0019] Thirdly, in this invention, the bottom of the box is a sloping surface with an inclination angle of 45-60 degrees. This inclination angle easily creates a certain amount of compressive force, which can simulate the angle of an actual car steering wheel, making the pressure holding simulation and burst simulation closer to the actual usage situation, and making the test results more accurate.

[0020] Fourthly, in this invention, pressure sensors fixed on multiple blades are used to detect the internal pressure of the airbag. The burst test divides the burst area by the data from different pressure sensors, thereby more quickly locating the burst point.

[0021] Fifth, in this invention, multiple pressure sensors for detecting the internal pressure value of the airbag are fixed on the same blade. The presence of multiple pressure sensors facilitates parallel testing of the same area, reduces the randomness of the test, and improves the accuracy of the test. Attached Figure Description

[0022] Figure 1 This is a front view of a device for detecting airbag pressure in this invention;

[0023] Figure 2 This is an isometric side view of a device for detecting airbag pressure in this invention.

[0024] Figure 3 This is the usage state of the airbag storage box in this invention. Figure 1 ;

[0025] Figure 4 This is the usage state of the airbag storage box in this invention. Figure 2 ;

[0026] 1. Gas tank; 2. Gas tank valve; 3. Control panel; 4. Display screen; 5. Frame; 6. Flip-up plate device; 7. Pull-out keyboard tray device; 8. Industrial computer; 9. Normally closed solenoid valve A; 10. Inflation device; 11. Pressure sensor II; 12. Normally closed solenoid valve B; 13. Pneumatic solenoid valve A; 14. Pressure gauge; 15. Pneumatic solenoid valve B; 16. Electro-proportional valve; 17. Airbag housing device; 171. Blade; 172. Pressure sensor I; 173. Housing; 174. Sloping surface; 175. Arc-shaped connector. Detailed Implementation

[0027] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0028] like Figure 1-4 As shown, a device for detecting the pressure of an airbag includes an air tank 1, an airbag housing device 17, and an airbag. The air tank 1 is connected to the airbag through an air passage assembly and is used to inflate and maintain the pressure of the airbag or to burst it. The airbag housing device 17 includes a box 173, blades 171, and a pressure sensor 172. The bottom of the box 173 is provided with a through hole for cooperating with the pipeline assembly. The inside of the box 173 is provided with a groove for placing the airbag. The top of the box 173 is provided with an opening, and the top of the box 173 is provided with four blades 171 for generating resistance to the airbag. The inner wall of the blades 171 is provided with a pressure sensor 172.

[0029] Furthermore, the number of blades 171 includes, but is not limited to, four, six, eight, etc., which can be adjusted according to actual needs. The purpose is to perform regional detection of the internal air pressure of the airbag.

[0030] Furthermore, the number of pressure sensors 172 on blade 171 includes, but is not limited to, one, two, three, etc., which can be selected according to the actual situation. The purpose is to detect airbags in the same area. Multiple pressure sensors 172 can perform parallel detection in the same area, which helps to reduce random errors during detection and improve the accuracy of detection.

[0031] like Figure 1-4 The blade 171 is rotatably connected to the housing 173 at one end via an arc-shaped connector 175, and the four blades 171 are brought together to form a hemispherical body for closing the opening. More specifically, the inner wall of the housing 173 is provided with a pivot groove, and the lower ends of the arc-shaped connector 175 are rotatably connected to the inside of the pivot groove via pins.

[0032] Furthermore, the four blades 171 exert resistance on the airbag through the friction between the arc-shaped connector 175 and the box 173, as well as their own weight, thereby simulating the resistance that exists when the airbag is actually used, making it closer to the actual use of the airbag.

[0033] like Figure 1-4 As shown, the gas path assembly includes a gas pipe equipped with a pressure sensor 11, an electro-proportional valve 16 for controlling gas pressure, pneumatic solenoid valves A13 and B15 for adjusting the gas flow direction, and normally closed solenoid valves A9 and B12 for adjusting gas guidance in static and dynamic simulations. The gas path assembly includes an inflation and pressure-holding gas path and a bursting gas path. In the inflation and pressure-holding gas path, gas originates from the gas storage tank 1 and passes sequentially through pneumatic solenoid valve B15, electro-proportional valve 16, pneumatic solenoid valve A13, normally closed solenoid valve A9, and pressure sensor 11, finally reaching the airbag. Pressure sensor 11 collects data every 10ms, with a collection time of 6-12s or more. Simultaneously, pressure sensor 172 on blade 171 monitors the internal pressure increase of the airbag in real time.

[0034] Furthermore, in the rupture gas path, gas originates from the gas storage tank 1 and is sequentially transported through the large pipelines of normally closed solenoid valve B12 and normally closed solenoid valve A9, thereby instantly filling the airbag with gas. The inflation pipeline is then closed. After a preset time, pressure sensor 11 detects the pressure value at the bottom of the airbag. Simultaneously, the blades 171 on the outside of the airbag open and close as the airbag pressure value increases. Pressure sensor 172 on the blades 171 performs multi-point testing inside the airbag. When the airbag ruptures, the rupture area can be determined based on the test value of pressure sensor 172, allowing for further improvements.

[0035] Furthermore, during the blast test, the pressure values ​​of pressure sensors 172 on different blades 171 are compared to identify anomalies as blast zones, allowing for improvements and reducing manpower and material resources required for blasting. For example, if the pressure change curve of pressure sensor 172 on one blade 171 differs significantly from the pressure change curves of pressure sensors 172 on the other blades during the blast test, then the airbag area corresponding to pressure sensor 172 on that blade 171 is considered the blast zone. During blasting, a significant and concentrated strong airflow occurs in the blast zone of the airbag within a very short time (0-50ms after blasting), causing the pressure change curve of pressure sensor 1 corresponding to the blast zone to exhibit significant abnormal fluctuations within that very short time, differing from the pressure change curves of other pressure sensors 1 during the same period. Therefore, by comparing the pressure value change curves of all pressure sensors-172 (especially within 0-50ms after the explosion), it can be determined where the explosion zone is located, when the explosion occurs, and what the real-time pressure value of the pressure sensor-172 corresponding to the explosion zone is at the time of the explosion.

[0036] Furthermore, a threshold can be set for the blast test. If the real-time pressure value of the pressure sensor-172 corresponding to the blast area is equal to or greater than the threshold during blasting, it indicates that the airbag's compressive strength is qualified. If the real-time pressure value of the pressure sensor-172 corresponding to the blast area is less than the threshold during blasting, it indicates that the airbag's compressive strength is unqualified, meaning that the quality of the airbag needs to be improved, especially in the blast area.

[0037] like Figure 4 As shown, the bottom of the box 173 is a ramp 174 with an inclination angle of 45-60 degrees. The inclination angle is set to simulate the actual use of airbags on a car steering wheel. The angle can be adjusted by replacing the ramp 174 as needed.

[0038] Furthermore, the airbag placement device 17 is fixedly connected to the flipping plate device 6 via an air tube. The position of the airbag placement device is fixed between the air tube and the flipping plate device 6 by a clamp to prevent the airbag and the airbag placement device from shifting due to rapid pressurization.

[0039] like Figure 1-4 As shown, a method for testing a device for detecting airbag pressure includes the following steps:

[0040] a1) Turn on the industrial computer 8 and the display screen 4;

[0041] b1) Prepare the airbag and perform a self-check to prevent air leakage during inflation;

[0042] c1) Place the uninflated airbag inside the box 173, and connect one end of the air circuit assembly to the airbag's inflation port through the through hole, and connect the other end of the air circuit assembly to the air tank 1.

[0043] d1) Open the software, configure the system settings, select the items to be tested, including static tests and dynamic tests, and set the required test pressure and test time;

[0044] e1) Pressure holding test: Open the air tank 1. The pneumatic solenoid valve B15, the electro-proportional valve 16, the pneumatic solenoid valve A13, and the normally closed solenoid valve A9 are in the open state, and the normally closed solenoid valve B12 is in the closed state. The gas reaches the airbag through the above-mentioned gas circuit components. The airbag is placed in the airbag placement device 17. The blades 171 of the airbag placement device 17 gradually open and close as the airbag expands. The pressure sensor 172 fixed inside the blades 171 is always in close contact with the airbag to collect data in real time. The pressure sensor 11 collects data at fixed time intervals.

[0045] f1) Explosion test: Open the gas tank 1. Pneumatic solenoid valves A13 and B15 are closed. Open normally closed solenoid valves A9 and B12 to fill the gas bag with gas, causing the gas bag to inflate. The blades 171 on the outside of the gas bag open and close with the expansion of the gas bag. When the gas bag reaches the point of explosion, the pressure sensor 172 inside the blade 171 collects data in real time, and the pressure sensor 11 detects the pressure value of the gas bag at fixed time intervals.

[0046] g1) After the entire set of tests is completed, the airbag is replaced. After the replacement is completed, the blades 171 of the airbag placement device 17 are closed to prepare for the next airbag test.

[0047] Furthermore, the total duration and time intervals of the fixed time periods can be selected according to actual needs.

[0048] Furthermore, during the pressure holding test, the detection method mainly combines the data values ​​detected by pressure sensor 172 and pressure sensor 11 to plot the pressure versus time curve. The average value of the combined data is used to plot the curve, which helps to reduce the error generated during the test.

[0049] Furthermore, during the blasting test, the detection method uses pressure sensor 172 to detect the pressure value during blasting, and pressure sensor 11 to confirm the blasting area of ​​the airbag, thereby achieving the purpose of quickly locking the blasting location.

[0050] As a preferred method, the same airbag is first subjected to a pressure holding test (static test) to generate a Pt curve. The pressure critical value is derived from the curve, and then the burst test (dynamic test) is used to obtain an accurate pressure critical value. This is beneficial for testing and verification and for determining the pressure critical value, preventing the airbag from bursting due to exceeding the pressure critical value during use, thus failing to provide protection.

[0051] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. A method for detecting the pressure holding capacity of an airbag, characterized in that, The device for detecting the pressure of an airbag includes an air tank (1) and an airbag. The air tank (1) is connected to the airbag through an air circuit assembly and is used to inflate and maintain the pressure of the airbag or to burst it. The device for detecting the pressure of the airbag also includes an airbag placement device (17), which includes a box (173), blades (171) and a pressure sensor (172). The bottom of the box (173) is provided with a through hole for cooperating with the pipeline assembly. The inside of the box (173) is provided with a groove for placing the airbag. The top of the box (173) is provided with an opening, and the top of the box (173) is provided with multiple blades (171) for generating resistance to the airbag. The inner wall of the blades (171) is provided with a pressure sensor (172). The gas path assembly includes a gas pipe equipped with a pressure sensor (11), an electro-proportional valve (16) for controlling gas pressure, a pneumatic solenoid valve A (13) and a pneumatic solenoid valve B (15) for adjusting the direction of gas flow, and normally closed solenoid valves A (9) and B (12) for adjusting the gas guidance in static and dynamic simulations. The gas path assembly includes a pressure-holding gas path and a bursting gas path. In the pressure-holding gas path, the gas storage tank (1), pneumatic solenoid valve B (15), electro-proportional valve (16), pneumatic solenoid valve A (13), normally closed solenoid valve A (9), pressure sensor (11), and airbag are connected in sequence. In the bursting gas path, the gas storage tank (1), normally closed solenoid valve B (12), normally closed solenoid valve A (9), pressure sensor (11), and airbag are connected in sequence. When using the aforementioned device for detecting airbag pressure, the method includes the following steps: a1) Place the uninflated airbag inside the box (173) and connect one end of the air circuit assembly to the airbag inflation port through the through hole, and connect the other end of the air circuit assembly to the air tank (1). b1) Pressure holding test: Open the gas tank (1), pneumatic solenoid valve B (15), electric proportional valve (16), pneumatic solenoid valve A (13), and normally closed solenoid valve A (9) are in the open state. Gas reaches the airbag through the above-mentioned gas circuit components, causing the airbag to inflate. The blades (171) of the airbag placement device (17) rotate and open synchronously with the expansion of the airbag. The pressure sensor one (172) inside the blade (171) is always in close contact with the airbag to collect data in real time, and the pressure sensor two (11) collects data at a fixed time period at the bottom of the airbag. c1) Explosion test: Open the gas storage tank (1), open the normally closed solenoid valve A (9) and normally closed solenoid valve B (12), the gas reaches the airbag through the above gas circuit components, causing the airbag to inflate and expand. The blades (171) on the outside of the airbag open and close with the expansion of the airbag. The pressure sensor one (172) inside the blade (171) collects data in real time, and the pressure sensor two (11) detects the pressure value of the airbag at fixed time intervals.

2. The detection method for a device for detecting airbag pressure retention according to claim 1, characterized in that, One end of the blade (171) is rotatably connected to the box (173) via an arc-shaped connector (175), and multiple blades (171) together form a hemispherical body for closing the opening.

3. The detection method for a device for detecting airbag pressure retention according to claim 2, characterized in that, The number of blades (171) is four, six, or eight.

4. The detection method for a device for detecting airbag pressure retention according to claim 1, characterized in that, The bottom of the box (173) is a sloping surface (174), and the sloping surface (174) has an inclination angle of 45-60 degrees.

5. The detection method for a device for detecting airbag pressure retention according to claim 1, characterized in that: The pressure readings of the multiple pressure sensors (172) are used to confirm the blast zone.

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