pedestrian protection airbag device

Abstract

A pedestrian protection airbag device is provided, which can more effectively protect pedestrians under different conditions. The pedestrian protection airbag device (100) includes an airbag cushion (114) that expands and deploys from below the front hood (104) toward the windshield (108), and an inflator (112a, 112b) that supplies air to the airbag cushion (114). The airbag cushion (114) has: a first deployment portion (118) that expands and deploys along the lower part of the windshield (108); and a second deployment portion (120) that expands and deploys independently of the first deployment portion (118) and along the windshield (108) and A-pillars (110a, 110b). The second deployment portion (120) includes an overlap portion (130) that overlaps with at least a portion of the first deployment portion (118). The first inflator (112a) supplies gas to the first expansion section (118), and the second inflator (112b) supplies gas to the second expansion section (120).

Description

Technical Field

[0001] This invention relates to a pedestrian protection airbag device that expands and deploys from under the front hood of a vehicle toward the windshield. Background Technology

[0002] In recent years, pedestrian protection airbags have been developed as a distinct type of airbag, designed to protect pedestrians outside the vehicle, in addition to those designed to restrain occupants inside the vehicle. The main structure of these pedestrian protection airbags involves the airbag cushion inflating and deploying towards the windshield or other parts of the vehicle that may come into contact with the pedestrian's body when sensors installed at the front of the vehicle or elsewhere detect contact with the pedestrian.

[0003] Pedestrian protection airbag devices need to quickly cover the area within the vehicle where pedestrians may come into contact with the vehicle as the protected area. For example, in the pedestrian protection airbag device disclosed in Patent Document 1, in order to make the airbag 10 deploy as evenly as possible, two gas generators 30 are used. Each gas generator 30 is installed by inserting it into the air guide 20, and the gas is evenly supplied to a large area of ​​the airbag 10 through the air guide 20.

[0004] Existing technical documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2003-276537 Summary of the Invention

[0006] However, pedestrian protection airbags protect not only pedestrians but also cyclists. Since cyclists and their bicycles collide with the vehicle at high speed, cyclist airbags require a wider coverage area and higher internal pressure compared to those for pedestrians. As mentioned above, existing pedestrian protection airbag devices need a structure capable of more effectively protecting pedestrians in various conditions, including cyclists.

[0007] The problem the invention aims to solve

[0008] In view of the above-mentioned problems, the present invention aims to provide a pedestrian protection airbag device that can more effectively protect pedestrians and others under different conditions.

[0009] Problem Solving Methods

[0010] To address the aforementioned problems, the representative structure of the pedestrian protection airbag device according to the present invention includes an airbag cushion that expands and deploys from below the front hood of a vehicle toward the windshield, and a plurality of inflators supplying air to the airbag cushion. The airbag cushion is characterized by having: a first deployment portion that expands and deploys at least along the lower part of the windshield; and a second deployment portion that is provided independently of the first deployment portion to prevent gas flow with the first deployment portion, and expands and deploys along a predetermined range of the windshield and along a pair of A-pillars on both sides of the windshield in the vehicle width direction. The second deployment portion includes an overlap portion that overlaps at least a portion of the first deployment portion. The plurality of inflators includes a first inflator supplying gas to the first deployment portion and a second inflator supplying gas to the second deployment portion.

[0011] In the airbag structure described above, the first and second deployment sections expand and deploy independently of each other. This structure allows for increased internal pressure in both the first and second deployment sections, and enables separate control over their expansion and deployment. Therefore, this structure provides more effective protection for pedestrians under various conditions.

[0012] The first deployable section can be positioned near the front end inside the second deployable section. Thus, for example, the internal pressure of the first deployable section can be used to lift the front hood early, and then the second deployable section can be expanded and deployed early towards an area easily accessible to pedestrians.

[0013] The aforementioned first expansion section can expand from one side of a pair of A-pillars to the other. This first expansion section of the structure allows, for example, the front hood to be raised earlier and areas easily accessible to pedestrians to be covered earlier.

[0014] The first deployable portion can be configured to be contained within the second deployable portion. This structure also allows for the creation of an airbag cushion in which the first and second deployable portions can expand and deploy independently of each other.

[0015] The first deployable portion can be configured to contact the outer surface of the second deployable portion. This structure also allows for the creation of an airbag cushion in which the first and second deployable portions can expand and deploy independently of each other.

[0016] The overlapping portion of the second expansion section can be formed by a non-expandable portion. With this structure, it is also possible to achieve an airbag cushion in which the first and second expansion sections can expand and deploy independently of each other.

[0017] The first deployable section can expand and deploy earlier than the second deployable section. This first deployable section allows for earlier lifting of the front hood and earlier coverage of areas easily accessible to pedestrians.

[0018] The pedestrian protection airbag device also includes: a sensor installed at a specified location on the vehicle for detecting impact; and a control unit that controls the operation of the first inflator and the second inflator based on the impact detected by the sensor, wherein the control unit may activate only the first inflator when the impact detected by the sensor is less than a specified value.

[0019] With this structure, for example, when the impact is weak, if the object to be protected is determined to be a pedestrian, only the first expansion section is expanded to protect them; when the impact is large, if the object to be protected is determined to be a cyclist, the second expansion section is also expanded to protect them, and so on, the object to be protected can be further protected according to the situation.

[0020] The aforementioned airbag cushion may have one or more vent holes disposed in the first deployment section for discharging gas from the first deployment section. This structure allows for control of the pressure in the first deployment section to prevent it from becoming excessive.

[0021] The aforementioned one or more exhaust ports may include a portion disposed in the first expansion section adjacent to the second expansion section, and an exhaust port for releasing gas from the first expansion section into the interior of the second expansion section.

[0022] With the above structure, when the internal pressure of the first expansion section increases, the remaining gas is supplied from the first expansion section to the second expansion section, thereby accelerating the expansion and deployment of the second expansion section.

[0023] The aforementioned one or more vents may include vents for releasing gas from the first expansion section to the outside. This structure also allows for control of the pressure in the first expansion section to prevent it from becoming excessive.

[0024] When the internal pressure of the first expansion section reaches a predetermined value, one or more of the aforementioned vent holes can be opened. For example, a predetermined chain can be connected to the vent holes; when the chain is tightened, the vent holes are closed; when the internal pressure reaches the predetermined value, the chain is disconnected, thereby opening the vent holes. This structure can suppress gas from escaping from the vent holes, allowing the first expansion section to expand rapidly, and can control the pressure of the first expansion section from becoming excessive.

[0025] Invention Effects

[0026] According to the present invention, a pedestrian protection airbag device can be provided that can more effectively protect pedestrians and others under different conditions. Attached Figure Description

[0027] Figure 1 This is a diagram showing an outline of a pedestrian protection airbag device according to the first embodiment of the present invention.

[0028] Figure 2 Viewed from above Figure 1(a) An enlarged view of a pedestrian protection airbag device.

[0029] Figure 3 yes Figure 2 A cross-sectional view of the airbag cushion along line AA.

[0030] Figure 4 This is a diagram showing an outline of a pedestrian protection airbag device according to a second embodiment of the present invention.

[0031] Figure 5 yes Figure 4 A cross-sectional view of the airbag cushion along the BB line.

[0032] Figure 6 It is shown Figure 2 The figure shows an example of the deformation of the airbag cushion.

[0033] Figure 7 It is shown Figure 4 (b) is a diagram of a deformed example of an airbag cushion.

[0034] Figure 8 It is shown Figure 6 (a) is a diagram of a modified example of the vent hole. Detailed Implementation

[0035] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific values ​​shown in these embodiments are merely examples to facilitate understanding of the invention and, unless otherwise stated, do not limit the scope of the invention. Furthermore, in this specification and the accompanying drawings, elements having substantially the same function or structure are given the same symbols to avoid redundant descriptions, and illustrations of elements not directly related to the present invention are omitted.

[0036] (First Implementation)

[0037] Figure 1 This is a diagram showing an outline of the pedestrian protection airbag device 100 according to the first embodiment of the present invention. Figure 1 (a) is a diagram of a vehicle before the pedestrian protection airbag device 100 is activated. Figure 1 (b) is a diagram showing a vehicle with the pedestrian protection airbag device 100 in operation. In these... Figure 1 In the other diagrams, arrows F (Forward) and B (Back) indicate the forward and backward directions of the vehicle, arrows L (Left) and R (Right) indicate the left and right directions of the vehicle width, and arrows U (up) and D (down) indicate the vertical direction of the vehicle.

[0038] like Figure 1As shown in (a), the pedestrian protection airbag device 100 is located below the front hood 104 of the vehicle 102. The pedestrian protection airbag device 100 has impact detection sensors located, for example, inside the front bumper 106 or in other easily accessible areas such as near the pedestrian's legs. Its structure is such that when the sensor detects contact with a pedestrian, the control unit inflates the airbag via an inflator that serves as a gas generator. Figure 2 The first inflator 112a and the second inflator 112b send operation signals, and as... Figure 1 As shown in (b), the airbag cushion 114 expands and deploys from below the hood 104 toward the windshield 108.

[0039] like Figure 1 As shown in (a), the pedestrian protection airbag device 100 includes a housing 116 for housing the airbag cushion 114. The housing 116 is a long, box-shaped container made primarily of resin and is used to house the airbag cushion 114 (see [reference]). Figure 2 The inflators include the first inflator 112a, the second inflator 112b, etc. The housing 116 is oriented with its length facing the width of the vehicle and is mounted on the lower surface of the front hood 104 via a special bracket or the like.

[0040] like Figure 1 As shown in (b), the airbag cushion 114 of this embodiment expands and deploys along the windshield 108 to catch a pedestrian who is about to come into contact with the windshield 108. In addition, the airbag cushion 114 lifts the front hood 104 and causes it to float slightly. This action has the effect of mitigating the impact on pedestrians who come into contact with the front hood 104.

[0041] Figure 2 Viewed from above Figure 1 (a) An enlarged view of a pedestrian protection airbag device. The airbag pad 114 is bag-shaped and is formed by overlapping and sewing or bonding multiple base fabrics that constitute its surface, or by using OPW (One-Piece Woven) textiles, etc.

[0042] In this embodiment, multiple inflators are provided as first inflators 112a and second inflators 112b. These first inflators 112a, etc., are arranged along the width direction of the vehicle on the front end side of the airbag cushion 114. The first inflators 112a, etc., are fixed inside the housing 116 using studs (not shown), and are activated by an impact detection signal sent from a predetermined sensor, supplying gas to the airbag cushion 114. The airbag cushion 114 begins to inflate due to the gas from the first inflators 112a, etc., and the inflation pressure causes the housing 116 to crack, etc., and expands and unfolds toward the windshield 108.

[0043] In this embodiment, the first inflator 112a and the second inflator 112b are cylinder type. Currently common inflators include types that use a gas generating agent to produce gas through combustion, types that use compressed gas without generating heat to supply gas, and types that utilize a mixture of combustion gas and compressed gas simultaneously. Any of these types can be used as the first inflator 112a and the second inflator 112b.

[0044] In this embodiment, the expansion area of ​​the airbag cushion 114, where gas flows in and expands, is divided into a first expansion portion 118 and a second expansion portion 120. The second expansion portion 120 forms the periphery of the airbag cushion 114, and the first expansion portion 118 is in an expanded state inside the second expansion portion 120. That is, the airbag cushion 114 has a dual structure in which the second expansion portion 120 includes the first expansion portion 118.

[0045] The first expansion section 118 receives gas from the first inflator 112a and expands to cover the lower part of the windshield 108 between the left and right A-pillars 110a and 110b in the vehicle width direction, thereby catching the pedestrian's body over a larger area.

[0046] The second expansion section 120 is configured independently of the first expansion section 118 so that there is no gas flow with the first expansion section 118. The second expansion section 120 receives gas from the second inflator 112b and, in the state including the first expansion section 118, expands and unfolds along a pair of A-pillars 110a, 110b on both sides of the windshield 108 in the vehicle width direction.

[0047] The second expansion section 120 includes: a main expansion region 122, which includes the first expansion section 118 and expands along the windshield 108; and protruding expansion regions 124a and 124b, which protrude and expand from both ends of the main expansion region 122 in the vehicle width direction along the A-pillars 110a and 110b. The main expansion region 122, together with the internal first expansion section 118, provides a large-scale cover for the pedestrian's body. The protruding expansion regions 124a and 124b prevent the pedestrian's head or other parts from contacting the relatively rigid A-pillars 110a and 110b.

[0048] Figure 3 yes Figure 2 The airbag cushion is shown in a cross-sectional view along line AA. As described above, the airbag cushion 114 of this embodiment has a dual structure in which a first deployment portion 118 is included within a second deployment portion 120. Since the first deployment portion 118 and the second deployment portion 120 are inflated independently of each other using a first inflator 112a and a second inflator 112b, respectively, a high internal pressure can be maintained.

[0049] The first deployment section 118 is disposed near the front end inside the second deployment section 120. Furthermore, as described above, the first deployment section 118 has a shape that expands from the A-pillar 110a to the A-pillar 110b. Therefore, the airbag cushion 114 can, for example, utilize the internal pressure of the first deployment section 114 to lift the front hood 104 early, and then the second deployment section 120 can expand early towards an area easily accessible to pedestrians.

[0050] Furthermore, the first deployable section 118 is configured to have a smaller capacity than the second deployable section 120, thus allowing it to expand and deploy earlier than the second deployable section 120. This structure also allows the first deployable section 118 to raise the front hood 104 earlier and cover areas that may be easily accessible to pedestrians earlier.

[0051] The second unfolding portion 120 has an overlapping portion 130 that overlaps with at least a portion of the first unfolding portion 118. In this embodiment, the overlapping portion 130 is formed below the first unfolding portion 118, and the space between it and the first unfolding portion 118 is formed as a region where gas can flow in, but it can also be formed as a region where there is no space and the panels of the first unfolding portion 118 and the second unfolding portion 120 are in contact.

[0052] Refer again Figure 2 In this pedestrian protection airbag device 100, the operation of the first inflator 112a and the second inflator 112b can be controlled using sensors 126a and 126b and a control unit 128. For example, when the impact detected by sensors 126a and 126b is less than a predetermined value, the controller 128 can activate only the first inflator 112a.

[0053] Through the aforementioned control, for example, when the impact is weak, the control unit 128 can determine that the object of protection is a pedestrian and the vehicle speed of 102 is not high. In this case, the possibility of a pedestrian colliding with the windshield 108 is small. Therefore, the control unit 128 can lift the hood 104 by only expanding and unfolding the first unfolding part 118, thereby reducing the impact when a pedestrian contacts the hood 104.

[0054] When the impact detected by sensors 126a and 126b is a severe impact exceeding a specified value, the control unit 128 can determine that the object to be protected is a cyclist, and that the vehicle 102 is traveling at a high speed. In this situation, the cyclist or others may collide with the windshield 108. Therefore, the control unit 128 can inflate not only the first deployment section 118 but also the second deployment section 120, thereby providing more comprehensive protection for the cyclist or others. At this time, even if the second deployment section 120 is damaged due to a collision with the bicycle, the first deployment section 118 remains independent, thus maintaining the protection performance for the cyclist. Therefore, in the pedestrian protection airbag device 100, by using the control unit 128, the object to be protected can be protected according to the situation.

[0055] As described above, in the airbag cushion 114 of this embodiment, the first deployment portion 118 and the second deployment portion 120 expand and deploy independently of each other. Therefore, for example, by selectively operating the first inflator 112a and the second inflator 112b, the expansion and deployment of the first deployment portion 118 and the second deployment portion 120 can be controlled separately, and pedestrians and others under different conditions can be effectively protected as needed.

[0056] (Second Implementation)

[0057] Hereinafter, variations of the above-described constituent elements according to the second embodiment of the present invention will be described. Figure 4 This is a diagram showing an outline of the pedestrian protection airbag device 200 according to the second embodiment of the present invention. Figure 4 From this point forward, the same symbols will be used for constituent elements that are identical to those already described, and the descriptions of the already described constituent elements will be omitted. Furthermore, in the following description, even if constituent elements with the same names as those already described are given different reference numerals, they have the same function unless otherwise stated.

[0058] Figure 4 (a) is a top view of the pedestrian protection airbag device 200. Similarly, in this pedestrian protection airbag device 200, the expansion area where gas flows into the airbag cushion 202 and inflates is also divided into a first deployment section 204 and a second deployment section 206. However, the airbag cushion is structurally similar to... Figure 2 The difference of the airbag cushion 114 is that the first deployment part 204 and the second deployment part 206 are arranged adjacent to each other.

[0059] The first unfolding section 204 receives gas from the first inflator 112a and expands to cover the lower part of the windshield 108 between the A-pillars 110a and 110b in the vehicle width direction, thereby catching the pedestrian's body over a larger area.

[0060] The second expansion section 206 is disposed independently of the first expansion section 204, such that there is no gas flow between them. The second expansion section 206 receives gas from the second inflator 112b and is adjacent to the first expansion section 204. It expands and unfolds independently of the first expansion section 204 along a pair of A-pillars 110a, 110b on both sides of the windshield 108 in the vehicle width direction. The second expansion section 206 includes: a connecting region 208 that expands and unfolds in a state of connection with the periphery of the first expansion section 204; and protruding expansion regions 210a, 210b that protrude and expand from both ends of the connecting region 208 in the vehicle width direction along the A-pillars 110a, 110b.

[0061] Figure 4 (b) is Figure 4 (a) is a BB cross-sectional view of the airbag cushion 202. In the airbag cushion 202 of this embodiment, the first deployment portion 204 is independent of the second deployment portion 206 and expands and expands in a state of contact with the outer surface of the second deployment portion 206. The first deployment portion 204 is disposed on the front side of the vehicle of the second deployment portion 206, and the second deployment portion 206 expands and expands from the A-pillar 110a to 110b on the rear side of the vehicle of the first deployment portion 204.

[0062] The second unfolding portion 206 has an overlapping portion 212 that overlaps with at least a portion of the first unfolding portion 204. In this embodiment, the overlapping portion 212 is provided in the region below the first unfolding portion 204 that expands and unfolds.

[0063] The first deployable section 204 is positioned on the front side of the second deployable section 206. Furthermore, the capacity of the first deployable section 204 is set to be smaller than that of the second deployable section 206, allowing it to expand and deploy earlier than the second deployable section 206. These features enable the first deployable section 204 to raise the front hood 104 earlier and cover areas easily accessible to pedestrians earlier.

[0064] Refer again Figure 4 (a) In the pedestrian protection airbag device 200, the operation of the first inflator 112a and the second inflator 112b can also be controlled by sensors 126a and 126b and controller 128. The pedestrian protection airbag device 200 also uses the control unit 128, etc., to inflate and deploy only the first deployment part 204 to lift the front hood 104 when the impact is weak, while the second deployment part 206 inflates and deploys to protect the cyclist when the impact is strong, thereby protecting the target according to the situation.

[0065] As described above, in the airbag cushion 202 of this embodiment, the first deployment portion 204 and the second deployment portion 206 also expand and deploy independently of each other. Therefore, for example, by selectively operating the first inflator 112a and the second inflator 112b, the expansion and deployment of the first deployment portion 204 and the second deployment portion 206 can be controlled separately, thereby effectively protecting pedestrians and others under different conditions as needed.

[0066] Figure 5 It is shown Figure 4 (b) A variation of the airbag cushion 202 is shown in the figure for airbag cushion 220. The difference between this airbag cushion 220 and the airbag cushion 202 is that the overlapping portion 224 in the second deployment portion 222, which overlaps with at least a portion of the first deployment portion 204, is formed as a non-inflatable portion. In this structure, the gas in the second deployment portion 222 flows from the inflator 112b around the first deployment portion 204 to the protruding expansion regions 210a, 210b, as shown in Figure [reference needed]. Figure 4 (a).

[0067] In this airbag cushion 220, the first deployment portion 204 and the second deployment portion 222 also expand and deploy independently of each other. Therefore, for example, by selectively operating the first inflator 112a and the second inflator 112b, see... Figure 4 (a) The expansion and deployment of the first deployment part 204 and the second deployment part 222 can be controlled respectively, so as to effectively protect pedestrians and others under different conditions according to the situation.

[0068] Figure 6 It is shown Figure 2 The figure shows a modified example of airbag cushion 114, namely airbag cushion 240. Figure 6 (a) shows the corresponding Figure 2 The image shows the airbag cushion 240. The airbag cushion 240 is structurally similar to... Figure 2 The difference of the airbag cushion 114 is that it has two vent holes 242a and 242b.

[0069] Exhaust ports 242a and 242b are provided in the first expansion section 118 at a position adjacent to the second expansion section, and are configured to release gas from the first expansion section 118 into the interior of the second expansion section 120.

[0070] Figure 6 (b) is Figure 6(a) is a CC cross-sectional view of the airbag cushion 240. The vent 242a can be provided, for example, in the first deployment section 118 at a location where gas can be supplied to the protruding expansion region 124a of the second deployment section 120. By providing the vent 124a, when the internal pressure of the first deployment section 118 increases, the remaining gas is supplied from the first deployment section 118 to the second deployment section 120, particularly to the protruding expansion region 124a. With this structure, the pressure in the first deployment section 118 can be controlled to prevent it from becoming too high, and the expansion and deployment of the second deployment section 120 can be accelerated.

[0071] Figure 7 It is shown Figure 4 (b) A modified example of the airbag cushion 114 is shown in the figure of the airbag cushion 260. The airbag cushion 260 has an exhaust port 262 on the outward-facing portion of the first deployment portion 204. The exhaust port 262 can discharge gas outward from the first deployment portion 204 and can control the pressure of the first deployment portion 204 from becoming too high.

[0072] Furthermore, there is no limit to the number of exhaust holes 262 provided, and the number of exhaust holes 262 can be appropriately set according to the capacity and internal pressure of the first expansion section 204.

[0073] Figure 8 It is shown Figure 6 (a) is a variation of the exhaust port 242a, namely the exhaust port 280. Figure 8 (a) is a diagram showing the vent 280 in the closed state. The vent 280 is implemented as a so-called dynamic vent, and the opening is formed as a slit, which is kept closed by pulling the chain 282 from the inside of the first expansion portion 118.

[0074] The forked front end of the chain 282 is connected to the two edges of the vent 280. The root end of the chain 282 is exposed to the outside from the airbag cushion 284 and connected to the chain cutter 286.

[0075] Chain cutter 286 is a device for fastening chain 282. When a signal is received from the control unit 128, the internal blade moves and cuts chain 282, causing it to detach. Chain cutter 286 can be installed on a vehicle together with an inflator or the like.

[0076] Figure 8 (b) is a diagram showing the vent 280 in the open state. The vent 280 is configured to open when the internal pressure of the first expansion section 118 is above a predetermined value, the chain 282 is cut by the chain cutter 286. For example, the internal pressure of the first expansion section 118 can be controlled by the control unit 128 based on the pressure from the first inflator 112a (see reference 112a). Figure 6(a) The start time of operation is calculated, or a specified sensor is installed inside the first expansion section 118 to actually measure it. If the exhaust port 280 has these structures, the pressure in the first expansion section 118 can be effectively controlled to prevent it from becoming too high.

[0077] The gas discharged from the exhaust port 280 is released into, as Figure 6 (b) The vent 242a is inside the second expansion portion 120 adjacent to the first expansion portion 118, or as shown in the diagram. Figure 7 The vent 262 can be located on the outside of the airbag cushion 284. Furthermore, when multiple vents 280 are provided, vents for releasing gas into the interior of the second expansion section 120 and vents for releasing gas into the exterior of the airbag cushion 284 can be provided simultaneously.

[0078] If the airbag 284 has the exhaust port 280, it can be used as a replacement or auxiliary for a piston-type hood lifter. The piston-type hood lifter is used to lift the front hood 104 in an emergency (see...). Figure 1 (a) A mechanism to mitigate the impact on the object in contact.

[0079] like Figure 1 As shown in (b), the first expansion section 118 has the function of lifting the front hood 104 from below. By having an exhaust port 280, the first expansion section 118 first suppresses the discharge of gas and expands rapidly, thereby lifting the front hood 104. When the internal pressure is above a specified value, gas is supplied to the second expansion section 120 to form a larger confinement area, or the gas is discharged to the outside to prevent damage, etc., thus better realizing the function of a piston-type hood lifter.

[0080] The preferred embodiments of the present invention have been described above with reference to the accompanying drawings. These embodiments are preferred examples of the present invention, and other embodiments may be implemented or carried out in various ways. Unless otherwise specified in this specification, the present invention is not limited to the shape, size, and structural configuration of the detailed components shown in the drawings. Furthermore, the expressions and terminology used in this specification are for illustrative purposes and are not intended to limit the scope of the invention unless otherwise specified.

[0081] Therefore, those skilled in the art can conceive of various variations or modifications within the scope of the claims, and these should obviously also fall within the technical scope of this invention.

[0082] Industrial availability

[0083] The present invention can be used in pedestrian protection airbag devices having an airbag cushion that expands and deploys from under the front hood of a vehicle toward the windshield.

[0084] Symbol Explanation

[0085] 100… Pedestrian protection airbag device according to the first embodiment, 102… Vehicle, 104… Front hood, 106… Front bumper, 108… Windshield, 110a, 110b… A-pillar, 112a… First inflator, 112b… Second inflator, 114… Airbag cushion, 116… Outer shell, 118… First deployment section, 120… Second deployment section, 122… Main inflation region, 124a, 124b… Protruding inflation region, 126a, 126b… Sensor, 128… Control unit, 130… Overlapping section, 200… Pedestrian protection airbag device of the second embodiment, 202… Airbag cushion, 204… First deployment portion, 206… Second deployment portion, 208… Connecting area, 210a, 210b… Protruding expansion area, 212… Overlapping portion, 220… Airbag cushion of the modified example, 222… Second deployment portion, 224… Overlapping portion, 240… Airbag cushion, 242a, 242b… Vent, 260… Airbag cushion, 262… Vent, 280… Vent, 282… Chain, 284… Airbag cushion, 286… Chain cutter

Claims

1. A pedestrian protection airbag device including an airbag cushion that inflates and deploys from under a front hood of a vehicle toward a windshield, and a plurality of inflators that supply gas to the airbag cushion, characterized in that: the airbag cushion has: a first deployment portion that inflates and deploys at least along a lower portion of the windshield; and a second deployment portion that is provided independently of the first deployment portion so as not to communicate gas with the first deployment portion, and inflates and deploys along a prescribed range of the windshield and a pair of A pillars on both sides in a vehicle width direction of the windshield, the second deployment portion includes an overlapping portion that overlaps at least a portion of the first deployment portion, the plurality of inflators have: a first inflator that supplies gas to the first deployment portion; and a second inflator that supplies gas to the second deployment portion, the first deployment portion is disposed near a front end inside the second deployment portion, the first deployment portion inflates and deploys from one side of the pair of A pillars to the other side, the pedestrian protection airbag device further includes: a sensor that is installed at a prescribed position of the vehicle and detects an impact; and a control portion that controls operation of the first inflator and the second inflator in accordance with the impact detected by the sensor, when the impact detected by the sensor is less than a prescribed value, the control portion operates only the first inflator, and early lifts the front hood with internal pressure of the first deployment portion, when the impact detected by the sensor is a strong impact of the prescribed value or more, the control portion causes not only the first deployment portion to inflate and deploy, but also the second deployment portion to inflate and deploy.

2. The pedestrian protection airbag device according to claim 1, characterized in that: the first deployment portion is provided in a state of being contained within the second deployment portion.

3. The pedestrian protection airbag device according to claim 1, characterized in that: the first deployment portion is provided in a state of being in contact with an outer surface of the second deployment portion.

4. The pedestrian protection airbag device according to claim 3, characterized in that: the overlapping portion of the second deployment portion is formed by a non-inflating portion.

5. The pedestrian protection airbag device according to any one of claims 1 to 4, characterized in that: the first deployment portion completes inflation and deployment earlier than the second deployment portion.

6. The pedestrian protection airbag device according to any one of claims 1 to 4, characterized in that: the airbag cushion has one or a plurality of gas discharge holes that are provided in the first deployment portion and discharge gas from the first deployment portion.

7. The pedestrian protection airbag device according to claim 6, characterized in that: the one or a plurality of gas discharge holes include a gas discharge hole that releases gas from the first deployment portion to the outside.

8. The pedestrian protection airbag device according to claim 6, characterized in that: the one or a plurality of gas discharge holes are opened when internal pressure of the first deployment portion is the prescribed value or more. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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