Airbag gas generator filter optimized and improved for ventilation uniformity

Abstract

The invention provides a safety airbag gas generator filtering piece which is formed by winding a strip-shaped filtering material and comprises at least one first section and at least one second section, the first section and the second section are alternately distributed in the winding circumferential direction, and the wrapping angle of each section is not smaller than 360 degrees. The first section and the second section are respectively provided with holes in different directions, have the same air permeability, and meet the specific relation between porosity and hole edge rate. Through the arrangement of the inner side section group and the outer side section group, the inner side section adopts a long-edge hole geometric figure, and the outer side section adopts a short-edge geometric figure on the premise that the air permeability of the filtering piece is consistent, so that airflow guide and turbulent flow generation are optimized, and the impurity interception effect and the exhaust efficiency are improved. The sections are connected through welding to form a plurality of section groups with a labyrinth type air passage structure, so that the overall filtering performance is improved, the problem of air permeability caused by hole alignment is effectively prevented, and an efficient and uniform air filtering effect is realized.

Description

Technical Field

[0001] The invention relates to the field of edge detection, and in particular to a safety airbag gas generator filter element optimized and improved for air permeability uniformity. Background Art

[0002] With the rapid development of the automobile industry, the improvement and reliability of vehicle safety systems have become the focus of the industry. As an indispensable passive safety device in modern vehicles, airbags are designed to reduce the impact force on passengers by instantaneous inflation and cushioning when a collision occurs, thereby increasing the survival rate and safety factor of people in the car. As one of its core components, the airbag gas generator is responsible for quickly generating gas to inflate the airbag when an accident occurs.

[0003] In the gas generator, the filter plays an extremely critical role. Its functions include filtering impurities and dust in the gas to ensure that the gas entering the airbag is clean and to avoid performance instability or endangering the safety of passengers caused by impurities. Traditional filters are usually made of metal mesh, glass fiber, or ceramic materials, and achieve high-efficiency filtration through different physical structures and multi-layer combinations.

[0004] In recent years, the relevant technologies have been improved and optimized in many aspects to address the problems of high temperature, clogging and short life encountered by traditional airbag gas generator filters during use:

[0005] 1. In order to improve the high temperature resistance of the filter, researchers introduced new high temperature resistant materials, such as ceramic composite materials and high temperature metal alloys. These materials can remain stable under high temperature and high pressure environments, ensuring that the filter will not deform or fail due to heat when the gas is released quickly.

[0006] 2. In order to prevent the blockage problem that may occur during the gas flow process, the existing technology has optimized the structural design of the filter element. For example, the use of multi-layer mesh structure and high-permeability fiber stacking effectively increases the surface area of ​​the gas channel, while ensuring the efficient retention of impurities, thereby greatly reducing the risk of gas flow obstruction.

[0007] 3. Nano coating technology is also used to enhance the corrosion resistance and wear resistance of the filter element, so that it can maintain stable performance in long-term use. The addition of nano coating not only improves the durability of the filter element, but also reduces the impact of wear on gas generation efficiency.

[0008] In the existing airbag inflator filter technology, the problem of air permeability uniformity is still a key problem that needs to be solved urgently. Air permeability uniformity directly affects the gas release speed and inflation effect, and is the basis for ensuring rapid and uniform inflation of the airbag.

[0009] There are multi-layer and segmented filters in the prior art, such as CN217613705U. However, this patent only uses staggered holes to provide a labyrinth-like airway, and does not make any improvements on air permeability uniformity and airflow vortex along the holes. The existing filters have the following main problems in terms of air permeability uniformity:

[0010] 1. The uneven pore structure and distribution of the filter material will lead to unbalanced flow when the gas passes through. Most traditional filters use multi-layer metal mesh or fiber structures. It is difficult to maintain consistent pore size and distribution during the processing of these materials. As a result, when the gas passes through the filter, it is easy to form local high or low flow rate areas, affecting the uniformity of inflation and the overall deployment effect of the airbag.

[0011] 2. Existing filters still have deficiencies in dealing with deformation problems under high temperature and high pressure conditions. Under extreme conditions, thermal expansion or physical deformation of the material will further aggravate the uneven air permeability. This deformation will not only reduce the overall stability of the filter, but may also cause a significant decrease in the air permeability of local areas, thereby affecting the normal inflation speed and safety performance of the airbag.

[0012] 3. The impact of the accumulation of impurities and particles on air permeability uniformity cannot be ignored. In actual work, the tiny particles and impurities carried by the gas during release are easily intercepted and accumulated by the filter element, which will cause local pore blockage over time, further exacerbating the uneven air permeability. As a result, the path and speed of gas release become uncontrollable, and in severe cases, it may even cause safety hazards such as the airbag failing to deploy as designed.

[0013] 4. Existing technologies face a trade-off in balancing air permeability uniformity and other performance indicators (such as high temperature resistance and corrosion resistance). In order to enhance the high temperature resistance or corrosion resistance of the filter element, a denser or more complex material structure is usually introduced, which will lead to poor air permeability or difficulty in maintaining air permeability uniformity.

[0014] In summary, how to optimize the material and structure of the filter to achieve efficient and uniform air permeability while maintaining stability under high temperature and high pressure environments is an important challenge in current airbag inflator filter technology. Summary of the invention

[0015] In view of the above problems, the present invention aims to provide: a safety airbag gas generator filter element, the filter element is formed by winding a strip filter material 1; the strip filter material 1 comprises at least one first section 11 and at least one second section 12 in the winding circumferential direction; the first section 11 and the second section 12 are alternately and continuously distributed; the covering angle of any one of the first sections 11 or any one of the second sections (12) in the winding circumferential direction is not less than 360°;

[0016] The first section 11 is provided with a first hole 111, and the second section 12 is provided with a second hole 121; the first section 11 and the second section 12 satisfy the following relationship:

[0017]

[0018] Wherein, L and H respectively intercept the inspection sections with length L and width H on the first section and the second section, K1 and K2 respectively represent the void ratios of the first section and the second section, S1 and S2 respectively represent the areas of complete single holes on the inspection sections of the first section and the second section, N1 and N2 respectively represent the numbers of complete single holes on the inspection sections of the first section and the second section, and represents the total area of ​​incomplete holes on the investigated sections of the first and second sections respectively;

[0019] The first section 11 and the second section 12 adjacent thereto in the winding direction, which constitute a group, also satisfy the following relationship:

[0020]

[0021] Wherein, R1 and R2 represent the hole edge ratio of the first section and the second section respectively, which represents the side length of the hole per unit area; and Respectively represent the total side lengths of incomplete holes on the first and second sections.

[0022] Furthermore, the first hole 111 and the second hole 121 have the same geometric shape but different directions.

[0023] Furthermore, the first section 11 and the second section 12 have the same width.

[0024] Furthermore, the first section 11 and the second section 12 are connected by welding.

[0025] Furthermore, the first sections 11 have at least two, and the second sections 12 have at least two.

[0026] Furthermore, the two first sections 11 and the two second sections 12 constitute two consecutive sections, with the first wound section being the inner side and the second wound section being the outer side; for one section, the first section 11 is on the inner side and the second section 12 is on the outer side; two adjacent sections satisfy:

[0027]

[0028]

[0029] Among them, K 1-inner , K 2-inner , K 1-outer and K 2-outer R represents the porosity of the first and second segments of the inner segment group and the first and second segments of the outer segment group respectively; 1-inner , R 2-inner , R 1-outer and R 2-outer The hole edge rates of the first and second segments of the inner segment group and the first and second segments of the outer segment group are represented respectively.

[0030] Furthermore, the two first sections 11 and the two second sections 12 constitute two consecutive sections, with the first wound section being the inner side and the second wound section being the outer side; for one section, the first section 11 is on the inner side and the second section 12 is on the outer side; two adjacent sections satisfy:

[0031]

[0032]

[0033] Among them, K 1-inner , K 2-inner , K 1-outer and K 2-outer R represents the porosity of the first and second segments of the inner segment group and the first and second segments of the outer segment group respectively; 1-inner , R 2-inner , R 1-outer and R 2-outer The hole edge rates of the first and second segments of the inner segment group and the first and second segments of the outer segment group are represented respectively.

[0034] Furthermore, the welding is spot welding.

[0035] Furthermore, the welding is resistance welding.

[0036] Furthermore, the second hole 121 is obtained by rotating the first hole 111 around the geometric center by a specific angle.

[0037] The beneficial effects of the present invention are:

[0038] 1. Compared with the prior art, the present invention provides a solution for at least one group of segment groups. By arranging holes with the same geometric shape but different directions, the first segment and the second segment can have the same air permeability. By arranging the holes in a staggered direction, the problem of periodic alignment of the holes on the first segment and the holes on the second segment during the winding process can be avoided, thereby avoiding the problem of excessive or insufficient local air permeability due to "hole to hole" and "hole to plate".

[0039] 2. Compared with the prior art, a solution of multiple groups of segment groups is provided. On the basis of ensuring air permeability, a maze-like airway is constructed through multiple groups of segment groups with different hole directions, thereby improving the filtering effect of precious impurities.

[0040] 3. Compared with the prior art, the present invention improves the filtering effect while ensuring air permeability by setting the holes on the inner segment group to have a longer side length under the same area, such as polygon, star, petal shape, etc.; this is because the porosity of the inner and outer sides is the same, and the air permeability efficiency is the same; and the inner side adopts a geometric figure with a longer side length under the same area, and the air flow will generate turbulence (eddy, cyclone) at the edge of the hole. Such a setting can produce a stronger cyclone on the inside and intercept more impurities. Since the outer side has fewer impurities and lower air pressure, a geometric figure with a shorter side length under the same area, that is, a simpler rhombus, ellipse, circle, etc., is adopted, which can make the gas discharge smoother. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a structural schematic diagram of a filter element in the prior art;

[0042] Figure 2 A physical picture of a filter element in the prior art;

[0043] Figure 3 This is a light transmission test diagram of a filter element in the prior art (photographed at 0°);

[0044] Figure 4 This is a light transmission test diagram of a filter element in the prior art (photographed at 90°);

[0045] Figure 5 A schematic diagram of the structure of another filter element in the prior art;

[0046] Figure 6 A physical diagram of another prior art filter element;

[0047] Figure 7 This is a light transmission test diagram of another prior art filter element (photographed at 0°);

[0048] Figure 8 This is a light transmission test diagram of another prior art filter element (photographed at 90°);

[0049] Fig. 9 It is a structural schematic diagram of the filter element of the present invention;

[0050] Fig.10 A physical diagram of the filter element of the present invention;

[0051] Fig.11This is a light transmission test diagram of the filter element of the present invention (photographed at 0°);

[0052] Fig.12 This is a light transmission test diagram of the filter element of the present invention (photographed at 90°); DETAILED DESCRIPTION

[0053] In order to deepen the understanding of the present invention, the present invention will be further described in detail below in conjunction with examples. The examples are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0054] At present, the filters on the market are mainly made of stretched mesh wound and welded. There are two types of filters in large quantities, the difference is the form of the stretched mesh is different:

[0055] 1. The mesh spacing on the stretching net is the same and the size is the same, such as Figure 1 The structure diagram and Figure 2 As shown in the actual picture, Figure 3 and Figure 4 For light transmission test, Figure 3 It shows the problem of excessive local air permeability due to "hole to hole". Figure 4 It shows the problem of local low air permeability due to "hole to plate".

[0056] 2. The stretching net is multi-segment (integrated multi-segment), and the mesh spacing of each segment is the same and the size is the same (the mesh spacing within the length of A is the same, the mesh spacing within the length of B is the same, and the mesh spacing within the length of C is the same). Figure 5 The structure diagram and Figure 6 As shown in the actual picture, Figure 7 and Figure 8 This is a light transmission test, and it shows a slit-like bright light, indicating that the air permeability is not uniform.

[0057] The filter element in the prior art has poor air permeability uniformity and is prone to local blockage.

[0058] Embodiment 1

[0059] like Fig. 9 The structure diagram and Fig.10As shown in the physical diagram, this embodiment proposes a safety airbag gas generator filter, which is formed by winding a strip filter material 1; the strip filter material 1 includes at least one first section 11 and at least one second section 12 in the winding circumferential direction; the first section 11 and the second section 12 are alternately and continuously distributed; the wrapping angle of any one of the first sections 11 or any one of the second sections (12) in the winding circumferential direction is not less than 360°; the first hole 111 and the second hole 121 have the same geometric shape but different directions; the second hole 121 is obtained by rotating the first hole 111 around the geometric center by a specific angle. The first section 11 and the second section 12 have the same width; the first section 11 and the second section 12 are connected by welding.

[0060] The first section 11 is provided with a first hole 111, and the second section 12 is provided with a second hole 121; the first section 11 and the second section 12 satisfy the following relationship:

[0061]

[0062] Wherein, L and H respectively intercept the inspection sections with length L and width H on the first section and the second section, K1 and K2 respectively represent the void ratios of the first section and the second section, S1 and S2 respectively represent the areas of complete single holes on the inspection sections of the first section and the second section, N1 and N2 respectively represent the numbers of complete single holes on the inspection sections of the first section and the second section, and represents the total area of ​​incomplete holes on the investigated sections of the first and second sections respectively;

[0063] The first section 11 and the second section 12 adjacent thereto in the winding direction, which constitute a group, also satisfy the following relationship:

[0064]

[0065] Wherein, R1 and R2 represent the hole edge ratio of the first section and the second section respectively, which represents the side length of the hole per unit area; and Respectively represent the total side lengths of incomplete holes on the first and second sections.

[0066] Fig.10 and Fig.11 This is a light transmission test, which was shot at 0° and 90°, respectively, showing that the object of the present invention has good light transmission (air permeability) uniformity.

[0067] This embodiment provides a solution for at least one group of segment groups. By arranging holes with the same geometric shape but different directions, the first segment and the second segment can have the same air permeability. By arranging the holes in a staggered direction, the problem of periodic alignment of the holes on the first segment and the holes on the second segment during the winding process can be avoided, thereby avoiding the problem of excessive or insufficient local air permeability due to "hole to hole" and "hole to plate".

[0068] Embodiment 2

[0069] This embodiment provides a filter element for an airbag gas generator, the filter element being formed by winding a strip filter material 1; the strip filter material 1 comprises at least one first section 11 and at least one second section 12 in the winding circumferential direction; the first sections 11 and the second sections 12 are alternately and continuously distributed; the wrapping angle of any one of the first sections 11 or any one of the second sections (12) in the winding circumferential direction is not less than 360°;

[0070] The first section 11 is provided with a first hole 111, and the second section 12 is provided with a second hole 121; the first section 11 and the second section 12 satisfy the following relationship:

[0071]

[0072] Wherein, L and H respectively intercept the inspection sections with length L and width H on the first section and the second section, K1 and K2 respectively represent the void ratios of the first section and the second section, S1 and S2 respectively represent the areas of complete single holes on the inspection sections of the first section and the second section, N1 and N2 respectively represent the numbers of complete single holes on the inspection sections of the first section and the second section, and represents the total area of ​​incomplete holes on the investigated sections of the first and second sections respectively;

[0073] The first section 11 and the second section 12 adjacent thereto in the winding direction, which constitute a group, also satisfy the following relationship:

[0074]

[0075] Wherein, R1 and R2 represent the hole edge ratio of the first section and the second section respectively, which represents the side length of the hole per unit area; and Respectively represent the total side lengths of incomplete holes on the first and second sections.

[0076] The first hole 111 and the second hole 121 have the same geometric shape but different directions; the first section 11 and the second section 12 have the same width. Furthermore, the first section 11 and the second section 12 are connected by welding.

[0077] The second hole 121 is obtained by rotating the first hole 111 around the geometric center at a specific angle; the first section 11 has at least two, and the second section 12 has at least two; the two first sections 11 and the two second sections 12 constitute two continuous sections, with the first wound section as the inner side and the last wound section as the outer side; for one section, the first section 11 is on the inner side and the second section 12 is on the outer side; two adjacent sections satisfy:

[0078]

[0079]

[0080] Among them, K 1-inner , K 2-inner , K 1-outer and K 2-outer R represents the porosity of the first and second segments of the inner segment group and the first and second segments of the outer segment group respectively; 1-inner , R 2-inner , R 1-outer and R 2-outer分 Respectively represent the hole edge rates of the first segment and the second segment of the inner segment group and the first segment and the second segment of the outer segment group.

[0081] The two first sections 11 and the two second sections 12 constitute two consecutive sections, with the first section wound as the inner side and the second section wound as the outer side. For one section, the first section 11 is on the inner side and the second section 12 is on the outer side. Two adjacent sections satisfy:

[0082]

[0083]

[0084] Among them, K 1-inner , K 2-inner , K 1-outer and K 2-outer R represents the porosity of the first and second segments of the inner segment group and the first and second segments of the outer segment group respectively; 1-inner , R 2-inner , R 1-outer and R 2-outer The hole edge rates of the first and second segments of the inner segment group and the first and second segments of the outer segment group are represented respectively.

[0085] This embodiment provides a solution of multiple groups of segment groups on the basis of the first embodiment. On the basis of ensuring air permeability, a labyrinth airway is constructed by using multiple groups of segment groups with different hole directions, thereby improving the filtering effect of precious impurities.

[0086] Embodiment 3

[0087] This embodiment provides a filter element for an airbag gas generator, the filter element being formed by winding a strip filter material 1; the strip filter material 1 comprises at least one first section 11 and at least one second section 12 in the winding circumferential direction; the first sections 11 and the second sections 12 are alternately and continuously distributed; the wrapping angle of any one of the first sections 11 or any one of the second sections (12) in the winding circumferential direction is not less than 360°;

[0088] The first section 11 is provided with a first hole 111, and the second section 12 is provided with a second hole 121; the first section 11 and the second section 12 satisfy the following relationship:

[0089]

[0090] Wherein, L and H respectively intercept the inspection sections with length L and width H on the first section and the second section, K1 and K2 respectively represent the void ratios of the first section and the second section, S1 and S2 respectively represent the areas of complete single holes on the inspection sections of the first section and the second section, N1 and N2 respectively represent the numbers of complete single holes on the inspection sections of the first section and the second section, and represents the total area of ​​incomplete holes on the investigated sections of the first and second sections respectively;

[0091] The first section 11 and the second section 12 adjacent thereto in the winding direction, which constitute a group, also satisfy the following relationship:

[0092]

[0093] Wherein, R1 and R2 represent the hole edge ratio of the first section and the second section respectively, which represents the side length of the hole per unit area; and Respectively represent the total side lengths of incomplete holes on the first and second sections.

[0094] The first hole 111 and the second hole 121 have the same geometric shape but different directions; the first section 11 and the second section 12 have the same width. Furthermore, the first section 11 and the second section 12 are connected by welding.

[0095] The two first sections 11 and the two second sections 12 constitute two consecutive sections, with the first section wound as the inner side and the second section wound as the outer side. For one section, the first section 11 is on the inner side and the second section 12 is on the outer side. Two adjacent sections satisfy:

[0096]

[0097]

[0098] Among them, K 1-inner , K 2-inner , K 1-outer and K 2-outer r represents the porosity of the first and second segments of the inner segment group and the first and second segments of the outer segment group respectively; 1-inner , R 2-inner , R 1-outer and R 2-outer The hole edge rates of the first and second segments of the inner segment group and the first and second segments of the outer segment group are represented respectively.

[0099] This embodiment is based on the second embodiment. By setting the holes on the inner section group to have a longer side length under the same area, such as a polygon, a star, a petal shape, etc., the filtering effect can be improved while ensuring air permeability. This is because the porosity of the inside and the outside is the same, and the air permeability efficiency is the same. The inside adopts a geometric figure with a longer side length under the same area, and the air flow will generate turbulence (eddy current, cyclone) at the edge of the hole. Such a setting can produce a stronger cyclone on the inside and intercept more impurities. Since the outside has fewer impurities and lower air pressure, a geometric figure with a shorter side length under the same area, that is, a simpler rhombus, ellipse, circle, etc., is adopted, which can make the gas discharge smoother.

[0100] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A filter element for an airbag gas generator, the filter element being formed by winding a strip filter material (1), characterized in that: The strip-shaped filter material (1) comprises at least one first section (11) and at least one second section (12) in the winding circumferential direction; The first sections (11) and the second sections (12) are alternately and continuously distributed; The wrapping angle of any one of the first sections (11) or any one of the second sections (12) in the winding circumferential direction is not less than 360°; The first section (11) is provided with a first hole (111), and the second section (12) is provided with a second hole (121); The first section (11) and the second section (12) satisfy the following relationship: Wherein, L and H respectively intercept the inspection segments of length L and width H on the first segment and the second segment, k1 and K2 respectively represent the void ratios of the first segment and the second segment, S1 and S2 respectively represent the areas of complete single holes on the inspection segments of the first segment and the second segment, N1 and N2 respectively represent the numbers of complete single holes on the inspection segments of the first segment and the second segment, and represents the total area of ​​incomplete holes on the investigated sections of the first and second sections respectively; A first section (11) constituting a group and a second section (12) adjacent thereto in the winding direction also satisfy the following relationship: Wherein, R1 and R2 represent the hole edge ratio of the first section and the second section respectively, which represents the side length of the hole per unit area; and Respectively represent the total side lengths of incomplete holes on the first and second sections.

2. The airbag gas generator filter according to claim 1, characterized in that: The first hole (111) and the second hole (121) have the same geometric shape but different directions.

3. The airbag gas generator filter according to claim 1, characterized in that: The first section (11) and the second section (12) have the same width.

4. The airbag gas generator filter according to claim 1, characterized in that: The first section (11) and the second section (12) are connected by welding.

5. The airbag gas generator filter according to claim 1, characterized in that: The first section (11) has at least two, and the second section (12) has at least two;.

6. The airbag gas generator filter according to claim 5, characterized in that: The two first sections (11) and the two second sections (12) form two consecutive section groups, with the sections wound first being the inner side and the sections wound later being the outer side; for one section group, the first section (11) is on the inner side and the second section (12) is on the outer side; Two adjacent groups of sections meet the following conditions: Among them, k 1-inner , K 2-inner , k 1-outer and K 2-outer R represents the porosity of the first and second segments of the inner segment group and the first and second segments of the outer segment group, respectively; 1-nner , R 2-inner , R 1-outer and R 2-outer The hole edge rates of the first and second segments of the inner segment group and the first and second segments of the outer segment group are represented respectively.

7. The airbag gas generator filter according to claim 5, characterized in that: The two first sections (11) and the two second sections (12) form two consecutive section groups, with the sections wound first being the inner side and the sections wound later being the outer side; for one section group, the first section (11) is on the inner side and the second section (12) is on the outer side; Two adjacent groups of sections meet the following conditions: Among them, K 1-inner , K 2-inner , K 1-outer and N 2-outer R represents the porosity of the first and second segments of the inner segment group and the first and second segments of the outer segment group, respectively; 1-inner , R 2-inner , R 1-outer and R 2-outer The hole edge rates of the first and second segments of the inner segment group and the first and second segments of the outer segment group are respectively represented.

8. The airbag gas generator filter according to claim 4, characterized in that: The welding is spot welding.

9. The airbag gas generator filter according to claim 4, characterized in that: The welding is resistance welding.

10. The airbag gas generator filter according to claim 2, characterized in that: The second hole (121) is obtained by rotating the first hole (111) around the geometric center by a specific angle.

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