Pedestrian airbag system

Abstract

To provide an airbag device for a pedestrian, which can stably discharge an expansion gas from an airbag when the pedestrian is caught.SOLUTION: This airbag device for the pedestrian comprises: an airbag 30 folded to be received in a storage disposed near the rear end of a vehicle hood panel; and an inflator that supplies an expansion gas to the airbag. The airbag is configured to cover the upper surface 5a side of a front pillar 5L when expansion completed. The airbag is provided with a vehicle body side wall 31 disposed on a lower surface side which becomes a body side of a vehicle when the expansion is completed, and a pedestrian side wall 32 disposed on an upper surface side to face the vehicle body side wall. A gas discharge part 55 opened when the pedestrian is caught to be able to discharge an inside expansion gas G is disposed on the vehicle body side wall side.SELECTED DRAWING: Figure 11

Description

【Technical Field】 【0001】 The present invention relates to a pedestrian airbag device disposed near the rear end of a hood panel of a vehicle. 【Background Art】 【0002】 Normally, a pedestrian airbag device is configured to receive and protect a pedestrian (including a cyclist) who has collided with a vehicle by an inflated airbag. However, in a pedestrian airbag device, since the time from the detection of the collision between the vehicle and the pedestrian to the start of receiving the pedestrian is relatively long, it is necessary to maintain the internal pressure of the airbag relatively high for a relatively long time. Also, in order to smoothly protect the pedestrian by the inflated airbag, it is desirable that the internal pressure of the airbag at the time of receiving is not too high. From such a viewpoint, conventionally, as a pedestrian airbag device, a vent hole is provided on the side of the front wall portion disposed on the front side (pedestrian side) at the time of completion of inflation, and this vent hole is opened only at the time of receiving the pedestrian, and while exhausting the internal inflation gas, there has been a configuration in which the pedestrian is received by the inflated airbag (see, for example, Patent Document 1). 【Prior Art Documents】 【Patent Documents】 【0003】 【Patent Document 1】 Japanese Patent Application Laid-Open No. 2007-253923 【Summary of the Invention】 【Problems to be Solved by the Invention】 【0004】 However, in the conventional pedestrian airbag device, since the vent hole is formed to open on the side of the front wall portion on the pedestrian side, there is a case where the pedestrian may contact so as to block this vent hole, and in such a case, there is a risk that the inflation gas in the airbag cannot be stably exhausted. 【0005】 The present invention aims to solve the above-mentioned problems and to provide a pedestrian airbag device that can stably release inflation gas from the airbag when a pedestrian is caught. [Means for solving the problem] 【0006】 The pedestrian airbag device according to the present invention comprises an airbag that is folded and stored in a storage area located near the rear end of the vehicle's hood panel, and an inflator that supplies inflation gas to the airbag. A pedestrian airbag system is configured such that, upon completion of inflation, the airbag covers at least the rear end of the hood panel or the upper surface of the front pillar. The airbag is configured to include a vehicle body side wall portion positioned on the lower side, which faces the vehicle body when inflation is complete, and a pedestrian side wall portion positioned on the upper side, opposite the vehicle body side wall portion. It is also characterized in that a gas discharge portion is provided on the vehicle body side wall portion, which opens when a pedestrian is caught, allowing the internal inflation gas to be discharged. 【0007】 In the pedestrian airbag device of the present invention, a gas discharge section, which is configured to open and release inflation gas when a pedestrian is caught, is located on the vehicle body side wall portion of the airbag, on the underside that faces the vehicle body when inflation is complete. In other words, in the pedestrian airbag device of the present invention, the gas discharge section is formed in an area of ​​the airbag that does not come into contact with the pedestrian when inflation is complete, so that it is prevented from being blocked by the pedestrian when a pedestrian is caught, and the inflation gas can be released smoothly. Furthermore, this gas discharge section is configured to open when a pedestrian is caught, or in other words, it is closed before a pedestrian is caught, so the airbag can maintain a high internal pressure state with suppressed leakage of inflation gas before a pedestrian is caught. In other words, in the pedestrian airbag device of the present invention, the inflated airbag releases inflation gas for the first time when a pedestrian is caught, and while releasing the inflation gas, the airbag, which has been adjusted to an appropriate internal pressure, can smoothly protect the pedestrian. 【0008】 Therefore, the pedestrian airbag device of the present invention can stably release inflation gas from the airbag when a pedestrian is caught. 【0009】 Furthermore, in the pedestrian airbag device of the present invention, the airbag is configured to include a pillar cover portion that extends substantially along the front-rear direction so as to cover the upper surface of the front pillar when inflation is complete. It is preferable to configure the gas exhaust section to be located in the pillar cover section at a position outside the center in the vehicle width direction. 【0010】 With the above configuration, the pedestrian airbag system can protect pedestrians from the front pillar by the pillar cover when the airbag has finished inflating. Furthermore, in the above configuration of the pedestrian airbag system, the gas discharge section is located away from the front windshield, which prevents the gas discharge section from approaching the front windshield when a pedestrian is caught, and further stabilizes the opening state of the gas discharge section when a pedestrian is caught. [Brief explanation of the drawing] 【0011】 [Figure 1] This is a plan view of a vehicle equipped with a pedestrian airbag system, which is one embodiment of the present invention. [Figure 2] This is a schematic longitudinal cross-sectional view showing a pedestrian airbag device according to an embodiment. [Figure 3] This is a plan view of the airbag used in the pedestrian airbag device of the embodiment, in a flat, unfolded state. [Figure 4] Figure 3 is a bottom view of the airbag. [Figure 5] Figure 3 is a schematic cross-sectional view of the airbag, and Figure 4 shows the VV section. [Figure 6] Figure 3 is a partially enlarged bottom view showing the gas discharge section of the airbag. [Figure 7] Figure 3 is a plan view showing the arrangement of the base materials that make up the airbag. [Figure 8] This is a plan view of the strap base material that constitutes the exhaust strap. [Figure 9] This is a plan view of a vehicle showing the state in which the pedestrian airbag device of the embodiment has completed inflation. [Figure 10] This is a schematic longitudinal cross-sectional view showing the left airbag in the pedestrian airbag device of the embodiment after it has completed inflation. [Figure 11] This is a schematic cross-sectional view showing the state of the pillar cover portion of the airbag before and after it receives a pedestrian, in the pedestrian airbag device of the embodiment, when inflation is complete. [Figure 12] This is a partially enlarged schematic cross-sectional view showing the state before and after the opening of the gas discharge section provided in the pillar cover portion of the pedestrian airbag device according to the embodiment. [Modes for carrying out the invention] 【0012】 Hereinafter, one embodiment of the present invention will be described with reference to the drawings. In this embodiment, as shown in Figures 1, 2, 9, and 10, two pedestrian airbag devices ML and MR mounted on the lower left and right ends near the rear end 8a of the hood panel 8 of a vehicle V will be used as an example for the description. In this specification, unless otherwise specified, the front-rear, up-down, and left-right directions will be described in accordance with the front-rear, up-down, and left-right directions of the vehicle V, respectively. 【0013】 Since the two pedestrian airbag devices ML and MR have the same configuration and are arranged symmetrically, in this embodiment, the pedestrian airbag device ML located on the left side will be used as an example for explanation, and the explanation of the pedestrian airbag device MR on the right side will be omitted. In this embodiment, when each pedestrian airbag device ML or MR is activated, the rear end 8a side of the hood panel 8 is lifted upward by an actuator (not shown) (see Figures 2 and 10). 【0014】 As shown in FIGS. 1 and 2, the pedestrian airbag device ML is disposed adjacent to a cowl 6 in a region behind the engine room (reference numerals omitted). The pedestrian airbag device ML includes an airbag 30, an inflater 22 that supplies inflation gas to the airbag 30, a case 15 as a storage part that stores the folded airbag 30 and the inflater 22, and an airbag cover 20 that covers the folded airbag 30. The cowl 6 is composed of a cowl panel 6a having high rigidity on the body side and a cowl louver 6b made of synthetic resin above the cowl panel 6a. Specifically, the pedestrian airbag device ML is disposed adjacent to a position on the front side of the cowl panel 6a (see FIG. 2). 【0015】 The case 15 is made of metal (sheet metal) and is fixed to a mounting part 2 composed of a flange or the like extending from the cowl panel on the body 1 side of the vehicle V by using bolts 26 and nuts 27 of a mounting bracket 25 of the inflater 22 (see FIG. 2). The case 15 has a substantially rectangular parallelepiped box shape with a protruding opening 15a for protruding the airbag 30 during inflation at the upper end side, and includes a substantially rectangular plate-shaped bottom wall portion 16 extending substantially along the left-right direction (vehicle width direction) of the vehicle V and a substantially rectangular tube-shaped peripheral wall portion 17 extending upward from the outer peripheral edge of the bottom wall portion 16. The case 15 is disposed on the front end side of the cowl 6 below the rear end 8a of the hood panel 8. 【0016】 The airbag cover 20 is arranged to extend forward from the cowl louver 6b in a substantially flush manner with the cowl louver 6b so as to cover the protruding opening 15a of the case 15. In the case of the embodiment, it is attached to a front side portion of the peripheral wall portion 17 in the case 15. The airbag cover 20 will be pushed open by the airbag 30 when the airbag 30 stored in the case 15 expands. 【0017】 As shown in Figures 2 and 4, the inflator 22 is a substantially cylindrical shape with its axial direction roughly aligned with the left-right direction (vehicle width direction) of the vehicle V, and is configured with a gas discharge section 23 for discharging expansion gas at its tip (left end in this embodiment). In this embodiment, the inflator 22 is held by a plurality (three in this embodiment) of mounting brackets 25, and is inserted into the airbag 30 with its periphery encased in an inner tube 50, and is fixed to the bottom wall 16 of the case 15 using bolts 26 of the mounting brackets 25 (see Figures 2 and 4). As described above, the bolts 26 of the mounting brackets 25 pass through the bottom wall 16 and are fastened with nuts 27 to the mounting section 2 on the body 1 side of the vehicle V, fixing the case 15 to the mounting section 2 together with the inflator 22 (see Figure 2). Furthermore, since the inflator 22 is inserted into the airbag 30, when the mounting bracket 25 is attached to the mounting portion 2, the airbag 30 is also attached and fixed to the bottom wall portion 16 of the case 15. The inflator 22 is configured to activate when a collision between the vehicle V and a pedestrian P is detected by a sensor (not shown) provided on the front bumper 3 of the vehicle V. 【0018】 As shown by the dashed lines in Figures 1 and 2 and in Figures 9 and 10, the airbag 30 comprises a case-side portion 34 positioned from the case 15 side to the lower surface of the rear end 8a of the hood panel 8 when inflation is complete, and a main body inflation portion 40 positioned to extend rearward from the case 15 when inflation is complete. Furthermore, as shown in Figures 3 to 5, the airbag 30 has substantially the same external shape and comprises a vehicle body side wall portion 31 positioned on the lower surface that becomes the body 1 side when inflation is complete, and a pedestrian side wall portion 32 positioned on the upper surface opposite the vehicle body side wall portion 31. The outer edges of the vehicle body side wall portion 31 and the pedestrian side wall portion 32 (the outer edges 75a, 67a of the vehicle body side panel 75 and the pedestrian side panel 76, which will be described later, are joined (sewn) together around the entire circumference to form a bag shape. 【0019】 The case-side portion 34 is formed to extend forward from the cowl cover portion 41 of the main body expansion portion 40, which will be described later. It is the rear end portion (main body expansion portion 40 side) when the expansion is complete, and is attached to the case 15. When the expansion is complete, it is configured to cover the area above the front side of the case 15, that is, below the area near the rear end 8a of the hood panel 8 (see Figure 10). In this embodiment, the case-side portion 34 is slightly narrower than the cowl cover portion 41 of the main body expansion portion 40 (smaller width dimension in the left-right direction), and its inner edge (right edge in this embodiment) on the vehicle width side is configured to roughly coincide with the inner edge (right edge) of the cowl cover portion 41. In the vehicle body side wall portion 31, an insertion opening 35 for inserting the inflator 22 into the rear end portion 34 is formed in the area that constitutes the rear end portion of the case-side portion 34 (see Figure 4). The insertion opening 35 includes an insertion slit 36 ​​for inserting the inflator 22, which is enclosed on its outer circumference by the inner tube 50, into the airbag 30, an insertion hole 37 for inserting the bolt 26 of the mounting bracket 25, and a cover panel 38 that closes the insertion slit 33 from the outer circumference. The insertion slit 36 ​​is formed in a substantially straight line substantially along the left-right direction, and the insertion hole 37 is formed in the area in front of the insertion slit 36 ​​(see Figures 4 and 7). The cover panel 38 covers the outer surface of the insertion slit 36, with its rear edge connected to the vehicle body side wall 31 behind the insertion slit 36, and a mounting hole 38a for the bolt 26 of the mounting bracket 25 to protrude is provided at the front end, corresponding to the insertion hole 37 (see Figure 7). 【0020】 The main inflatable section 40 is formed to extend from the case-side section 34 to the rear left when the airbag 30 is deployed flat, and includes a cowl cover section 41 positioned substantially along the left-right direction behind the case-side section 34, and a pillar cover section 42 extending rearward from the outer end (left end) of the cowl cover section 41 in the vehicle width direction. In this embodiment, the cowl cover section 41 is formed to extend only to the left (outward in the vehicle width direction) from the rear of the case-side section 34, and is configured to cover the upper surface near the edge (left end) in the vehicle width direction of the rear end 8a side of the hood panel 8, mainly the section from the cowl 6 to the lower part 4a side of the front windshield 4, when the airbag 30 has finished inflating. The pillar cover section 42 is configured to cover the upper surface (front) 5a side of the left front pillar 5L over substantially the entire front-to-rear area when the airbag 30 has finished inflating (see Figure 9). In this embodiment, the pillar cover portion 42 is wider than the cowl cover portion 41, and is configured to widely cover the upper surface 5a of the left front pillar 5L in the front, rear, left, and right directions (see Figures 3, 4, and 9). 【0021】 Furthermore, tethers 45, 46, and 47 are provided inside the airbag 30 to connect the pedestrian side wall portion 32 and the vehicle body side wall portion 31, thereby regulating the thickness when inflation is complete. Tether 45 is provided in the area excluding the rear end of the pillar cover portion 42, and in detail, it is provided continuously so as to extend front to back at a position approximately in the center in the width direction of the pillar cover portion 42 (approximately coinciding with the vehicle width direction). Tether 46 is provided partially on the front edge side near the boundary between the cowl cover portion 41 and the pillar cover portion 42. Tether 47 is provided approximately along the left-right direction near the boundary between the case side portion 34 and the cowl cover portion 41 (main body inflation portion 40), so as to partially close this boundary, and multiple (two in this embodiment) rectangular openings 47a are arranged side by side on the left-right side (see Figure 7). The length of the tether 47 is set to be smaller than the width of the case-side portion 34 in the left-right direction when it is laid flat. The expansion gas that flows into the case-side portion 34 flows into the main body expansion section 40 through the gaps formed on both ends of the tether 47 and the two openings 47a, 47a. 【0022】 The inner tube 50, which covers the outer circumference of the inflator 22, is configured as a roughly three-pronged cylindrical shape, as shown by the dashed line in Figure 4. It has an insertion cylinder portion 50a into which the inflator 22 with the mounting bracket 25 attached is inserted, and outlets 50b and 50c are provided on both sides from the location of the gas discharge portion 23 in the insertion cylinder portion 50a, with outlets 50b and 50c at the tips for releasing expansion gas. Mounting holes (not shown in the figure) are formed in the insertion cylinder portion 50a for passing through the bolts 26 of each mounting bracket 25. The inner tube 50 is made of a tube base material 85 as shown in Figure 7. 【0023】 Furthermore, the airbag 30 is provided with a gas discharge section 55 that opens when a pedestrian is caught, allowing the internal inflation gas G to be discharged. The gas discharge section 55 is located on the side of the vehicle body side wall 31 and specifically comprises a discharge opening 56 formed in the vehicle body side wall 31, an exhaust strap 65 having a cover portion 66 that can close the discharge opening 56, and a holding member 57 that can hold the cover portion 66 around the periphery of the discharge opening 56 (see Figures 4-6). In the embodiment, as shown in Figure 4, the gas discharge section 55 (55F, 55B) is configured such that the discharge opening 56 is located in the outer region 31a, which is further out to the left and right (left side in the embodiment) than the tether 45 in the part that constitutes the pillar cover portion 42 of the vehicle body side wall 31, and is arranged in two places side by side at the front and rear. 【0024】 In this embodiment, the discharge openings 56 formed in the vehicle body side wall portion 31 are formed at two locations on the vehicle body side wall portion 31, where the area constituting the pillar cover portion 42 is divided into three equal parts in the front-rear direction. More specifically, they are formed at a position approximately in the center between the joining portion 49 where the end of the tether 45 is sewn to the vehicle body side wall portion 31 and the left edge 42a (a position approximately in the left-right center of the outer region 31a). Each discharge opening 56 is formed in a circular shape. 【0025】 The retaining member 57 is positioned on the inner circumferential surface of the vehicle body side wall 31. Its outer shape is roughly rectangular with the front-to-rear direction being wider. The left edge 57a (outer edge in the vehicle width direction) and the right edge 57b (inner edge in the vehicle width direction) are joined (sewn) to the vehicle body side wall 31 by joining portions (sewn portions) 60 and 61, which are arranged roughly along the front-to-rear direction at positions corresponding to the left and right sides of the discharge opening 56, respectively (see Figures 4, 6, and 7). The retaining member 57 is capable of holding the cover portion 66 of the exhaust strap 65 by inserting the cover portion 66 of the exhaust strap 65 through the area between the vehicle body side wall 31 and the joining portions 60 and 61. In addition, an inner opening 58 is formed in the retaining member 57 at a position corresponding to the discharge opening 56. This inner opening 58, like the discharge opening 56, is formed as a roughly circular opening, but in this embodiment, its inner diameter is slightly larger than that of the discharge opening 56 (see Figure 6). Furthermore, in this embodiment, the connecting portions 60 and 61 that sew the left edge 57a and right edge 57b of the retaining member 57 to the vehicle body side wall portion 31, respectively, are formed to have different separation distances from the discharge opening 56. In this embodiment, as shown in Figure 6, the separation distance L1 between the connecting portion 60 located on the left side and the discharge opening 56 is greater than the separation distance L2 between the connecting portion 61 located on the right side and the discharge opening 56, and is set to about 2.5 times the separation distance L2. 【0026】 The exhaust strap 65 comprises a roughly rectangular plate-shaped cover portion 66 that can cover the exhaust opening 56, and a pair of connecting band portions 69, 69 extending from both sides of the cover portion 66 (in this embodiment, both the front and rear sides). In this embodiment, the exhaust strap 65 is formed by folding a strap base material 86, as shown in Figures 7 and 8, in half and sewing it at predetermined locations. 【0027】 The cover portion 66 is configured to be able to close the discharge opening 56 and to be able to open the discharge opening 56 when a pedestrian P is received. It is a roughly rectangular plate shape with a wider front-rear side and is arranged to be inserted between the retaining member 57 and the vehicle body side wall portion 31 (see Figures 5 and 6). In this embodiment, a double layer of reinforcing fabric 67 is provided on the inner circumferential surface side of the cover portion 66 (the side facing the pedestrian side wall portion 32). The reinforcing fabric 67 is made by folding a reinforcing base material 87, as shown in Figure 7, in half. The three sides of this reinforcing fabric 67, excluding the right edge, are sewn to the cover portion 66, and the right edge is sewn together with the cover portion 66 and the retaining member 57, thereby connecting the periphery of the reinforcing fabric 67 to the cover portion 66 over almost its entire circumference. Furthermore, the left edge 66a (outer edge), which is on the outside in the vehicle width direction, is not joined to the vehicle body side wall 31. The right edge 66b (inner edge), which is on the center side in the vehicle width direction, is sewn together with the joining portion 61 and joined to the vehicle body side wall 31 together with the retaining member 57. The left edge 66a (outer edge) of the cover portion 66 is located inside the joining portion 60 and close to the joining portion 60. 【0028】 The pair of connecting bands 69, 69 are formed to extend from the front edge 66c and rear edge 66d of the cover portion 66, respectively, and their tips 69a, 69a are joined (sewn) to the pedestrian side wall portion 32 at a position approximately directly above the discharge opening 56 when the airbag 30 has finished inflating (see Figure 5, 11A). In this embodiment, the tips 69a, 69a are joined to the pedestrian side wall portion 32 by the joining portion 70 (sewn portion) so that they overlap each other. The length of the connecting strap portion 69 (specifically, the separation distance L3 between the end of the connecting portion 49 that connects the cover portion 66 when the exhaust strap 65 is laid flat, and the end of the connecting portion 70 that connects the tips 69a, 69a to the pedestrian side wall portion 32, see Figure 8) is set to a length that allows it to be positioned taut inside the airbag 30 when the airbag 30 has finished inflating. 【0029】 In this exhaust strap 65, when the airbag 30 has finished inflating, the cover portion 66 is restricted by the retaining member 57 from moving toward the pedestrian side wall portion 32 (movement that causes it to float inward). Therefore, similar to the tethers 45, 46, and 47, the connecting band portions 69, 69 restrict the separation distance between the vehicle side wall portion 31 and the pedestrian side wall portion 32 (see Figure 11A). In the exhaust strap 65, the cover portion 66 is exposed in the area of ​​the inner opening 58. In other words, the cover portion 66 is directly subjected to the pressure from the inflation gas G that has flowed into the airbag 30 in the area of ​​the inner opening 58 (see Figure 12A). Therefore, after the airbag 30 has finished inflating, if a pedestrian P comes into contact with the area near the connection point 70 on the pedestrian side wall 32, the pedestrian side wall 32 deforms to move closer to the vehicle side wall 31, the pair of connecting bands 69, 69 loosen, and the cover 66 is pressed outward by the inflation gas G. The cover 66 then extends its left edge 66a (outer edge), which is not connected to the vehicle side wall 31, to the outside of the vehicle side wall 31, passing through the discharge opening 56 (see Figure 11B and Figure 12B), thereby opening the discharge opening 56. The excess inflation gas G is then exhausted from the discharge opening 56 of the gas discharge unit 55. 【0030】 As shown in Figure 7, the airbag 30 of this embodiment is composed of a vehicle side panel 75 constituting the vehicle side wall portion 31, a pedestrian side panel 76 constituting the pedestrian side wall portion 32, tether base materials 80, 81, 82 constituting the tethers 45, 46, 47, a tube base material 85 constituting the inner tube 50, a strap base material 86 constituting the exhaust strap 65, a reinforcing base material 87 constituting the reinforcing fabric 67, a cover panel 38, and a retaining member 57. These base materials are formed by cutting a coated fabric, which is made by weaving polyamide yarn or polyester yarn, with a gas leak prevention coating agent applied to its surface, into a predetermined shape. 【0031】 To describe the installation of the pedestrian airbag device ML of this embodiment into a vehicle, first, the airbag 30 is folded so that it can be stored inside the case 15, and with the inflator 22, which has the mounting bracket 25 already assembled, inserted into the inner tube 50, the airbag 30 is inserted into the case-side portion 34 using the insertion slit 36. Then, the bolts 26 of each mounting bracket 25 that protrude from the mounting holes (not shown in the figure) of the inner tube 50 are made to protrude from the insertion holes 37 of the airbag 30, and then the cover panel 38 is closed so as to cover the insertion slit 36, and the bolts 26 are inserted into the mounting holes 35a. After that, the airbag 30 and inflator 22 are stored inside the case 15, and the airbag cover 20 is attached to the case 15 to assemble the airbag assembly. Next, the case 15 is positioned in a predetermined location on the vehicle V, the bolts 26 protruding from the case 15 are secured to the mounting portion 2 with nuts 27, and the inflator 22 is connected to an operating circuit (not shown), thereby mounting the pedestrian airbag device ML onto the vehicle V. The pedestrian airbag device MR on the right side can be mounted onto the vehicle V in the same manner. 【0032】 In the pedestrian airbag devices ML and MR of this embodiment, an operating circuit (not shown) detects a collision between the vehicle V and a pedestrian (specifically, a pedestrian or cyclist) based on an operating signal from a sensor (not shown) located on the front bumper 3. When this occurs, the inflators 22, 22 are activated, causing the airbags 30, 30 to inflate by introducing inflation gas into them, and each inflates to cover the area from near the left or right end of the rear end 8a of the hood panel 8 to the upper surface (front) 5a of the front pillars 5L and 5R (see the dashed line in Figure 1 and Figures 9 and 10). 【0033】 Furthermore, in the pedestrian airbag device ML(MR) of this embodiment, the gas discharge section 55(55F, 55B), which is configured to open when a pedestrian is caught and exhaust the inflation gas G, is located on the side of the vehicle body wall 31, which is on the lower surface side that faces the vehicle body 1 when inflation is complete, in the airbag 30. In other words, in the pedestrian airbag device ML(MR) of this embodiment, the gas discharge section 55(55F, 55B) is formed in an area of ​​the airbag 30 that does not come into contact with the pedestrian P when inflation is complete, so that it is prevented from being blocked by the pedestrian P when a pedestrian is caught, and the inflation gas G can be exhausted smoothly (see B in Figure 11). Furthermore, the gas discharge section 55 (55F, 55B) is configured to open when a pedestrian is received (when the pedestrian P comes into contact with the pedestrian side wall 32). In other words, it is closed before the pedestrian is received (see Figures 11A and 12A), so the airbag 30 can maintain a high internal pressure state with suppressed leakage of inflation gas before the pedestrian is received. To put it another way, in the pedestrian airbag device ML (MR) of this embodiment, the inflated airbag 30 releases the inflation gas G for the first time when a pedestrian is received, and the pedestrian P can be smoothly protected by the airbag 30, which is adjusted to an appropriate internal pressure while releasing the inflation gas G. 【0034】 Therefore, in the pedestrian airbag device ML(MR) of this embodiment, when a pedestrian is detected, the inflation gas G can be stably exhausted from the airbag 30. 【0035】 Furthermore, in the pedestrian airbag device ML(MR) of this embodiment, the gas discharge section 55 (55F, 55B) is positioned outside the center of the pillar cover section 42 in the vehicle width direction. That is, in the pedestrian airbag device ML(MR) of this embodiment, since the airbag 30 has a pillar cover section 42, the pillar cover section 42 can protect the pedestrian P from the front pillar 5L(5R). Also, in the pedestrian airbag device ML(MR) of this embodiment, since the gas discharge section 55 (55F, 55B) is positioned away from the front windshield 4 (see A in Figure 11), it is possible to suppress the gas discharge section 55 (55F, 55B) from approaching the front windshield 4 when a pedestrian is caught, and the opening state of the gas discharge section 55 (55F, 55B) when a pedestrian is caught can be further stabilized. If these points are not taken into consideration, the gas exhaust section may be configured to be located inward (towards the front windshield) from the center in the vehicle width direction of the pillar cover. 【0036】 To describe in particular detail the gas discharge section 55 (55F, 55B) in the pedestrian airbag device ML(MR) of the embodiment, the cover section 66 that covers the discharge opening 56 has its right edge 66b, which is on the inside in the vehicle width direction, sewn to the vehicle body side wall 31 and the retaining member 57, and its left edge 66a, which is on the outside in the vehicle width direction, is extended from the discharge opening 56 so as to pass under the discharge opening 56, thereby opening the discharge opening 56 (see Figure 11B and Figure 12B). In other words, the cover portion 66 is configured such that the edge (left edge 66a) on the side with a larger separation distance from the front pillar 5L is the leading edge of the pillar cover portion 42, which expands in a roughly circular cross-section, and is extended out from the discharge opening 56. Therefore, even if the pillar cover portion 42 deforms to become flattened due to the deformation of the pedestrian side wall portion 32 when a pedestrian is caught (see B in Figure 11), the cover portion 66 can be smoothly extended out from the discharge opening 56, and the expansion gas G can be stably discharged. Of course, conversely to the embodiment, the cover portion may also be configured so that the edge on the central side in the vehicle width direction is extended out from the discharge opening. 【0037】 To explain in more detail, in the gas discharge section 55 (55F, 55B), the joint portion 60 that sews the left edge 57a of the retaining member 57 to the vehicle body side wall portion 31 has a greater separation distance from the discharge opening 56 than the joint portion 61 that sews the right edge 57b to the vehicle body side wall portion 31. In other words, in the gas discharge section 55 (55F, 55B), the amount of overlap between the area on the left edge 66a side, which is the leading edge when the cover portion 66 is opened, and the area around the discharge opening 56 on the vehicle body side wall portion 31 (the area that the left edge 66a side crosses when opened) is set to be large. Therefore, in the airbag 30 of this embodiment, before pedestrian detection, leakage of the inflation gas G that has flowed into the interior from the discharge opening 56 can be suppressed as much as possible. Furthermore, in the gas discharge section 55 (55F, 55B) of the embodiment, the inner opening 58 formed in the holding member 57 (the area where the inner circumferential surface of the cover section 66 is exposed) has an inner diameter that is larger than the inner diameter of the discharge opening 56. Therefore, when a pedestrian is stopped, the cover section 66 can be quickly extended from the discharge opening 56, and the expansion gas G can be discharged quickly and stably. 【0038】 Furthermore, in this embodiment, the gas discharge sections 55 (55F, 55B) are arranged at two locations, one at the front and one at the rear, which divide the entire length of the pillar cover section 42 into approximately three equal parts. In other words, they are arranged in the area near the middle of the front and rear of the pillar cover section 42. The arrangement and number of gas discharge sections are not limited to this embodiment. For example, one to three or more gas discharge sections may be provided, and they may also be arranged at the tip of the pillar cover section or at the outer edge in the vehicle width direction of the cowl cover section. In addition, from the viewpoint of ensuring that the gas discharge section opens and exhausts the expansion gas when a pedestrian is caught, it is desirable to arrange the gas discharge section near the area that actually comes into contact with the pedestrian. 【0039】 In the embodiments, a pedestrian airbag system is exemplified in which two airbags each cover an area from the lower side of the front pillar to the rear edge of the hood panel. However, the pedestrian airbag system to which the present invention can be applied is not limited to these embodiments. The present invention is also applicable to pedestrian airbag systems of the type that have one airbag comprising two pillar cover portions and a cowl cover portion arranged to connect these pillar cover portions. [Explanation of symbols] 【0040】 1...Body, 4...Front windshield, 5L, 5R...Front pillar, 8...Hood panel, 8a...Rear end, 15...Case, 22...Inflator, 30...Airbag, 31...Vehicle side wall, 32...Pedestrian side wall, 42...Cowl cover, 55 (55F, 55B)...Gas discharge section, G...Inflation gas, V...Vehicle, ML, MR...Pedestrian airbag system.

Claims

[Claim 1] The system comprises an airbag that folds and stores within a storage compartment located near the rear end of the vehicle's hood panel, and an inflator that supplies inflation gas to the airbag, A pedestrian airbag system is configured such that, upon completion of inflation, the airbag covers at least the rear end of the hood panel or the upper surface of the front pillar, The airbag is configured to include a vehicle body side wall portion positioned on the lower side, which faces the vehicle body when inflation is complete, and a pedestrian side wall portion positioned on the upper side, opposite the vehicle body side wall portion, and a gas discharge portion is provided on the vehicle body side wall portion, which is configured to open when a pedestrian is caught, allowing the internal inflation gas to be exhausted. The gas discharge section comprises a discharge opening formed in the side wall of the vehicle body, an exhaust strap having a cover portion capable of closing the discharge opening, and a retaining member capable of holding the cover portion at the periphery of the discharge opening. The retaining member is positioned on the inner circumferential surface side of the vehicle body side wall, and its two opposing edges are connected to the vehicle body side wall around the discharge opening, and the cover portion is inserted into the area between the connected portions and the vehicle body side wall, and an inner opening is provided at a position corresponding to the discharge opening. The exhaust strap extends from both sides of the cover portion in the direction along the connection portion, and each end comprises a pair of connecting bands that are connected to the pedestrian side wall portion. A pedestrian airbag device characterized in that the length of the connecting band portion is set to a length that allows it to be positioned taut inside the airbag when the airbag has finished inflating. [Claim 2] The aforementioned airbag is configured to include a pillar cover portion that extends substantially along the front-to-back direction so as to cover the upper surface of the front pillar when inflation is complete. The pedestrian airbag device according to claim 1, characterized in that the gas discharge section is located in the pillar cover section at a position outside the center in the vehicle width direction. [Claim 3] The pedestrian airbag device according to claim 1, characterized in that the connecting band portion is configured such that when the airbag has finished inflating, its tip is positioned approximately directly above the discharge opening. [Claim 4] The pedestrian airbag device according to claim 1, characterized in that the cover portion is configured such that the edge portion located on the central side in the vehicle width direction when the airbag has finished inflating is connected to the vehicle side wall portion together with the retaining member by one of the connecting portions, and the edge portion located on the outside in the vehicle width direction is positioned inside the other connecting portion.

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