Seat-mounted airbag device

Abstract

The present disclosure provides a seat-mounted airbag device. The seat-mounted airbag device includes an airbag main body having a front-rear chamber, left-right chambers, and a top-end chamber. The front-rear chamber is deployed from one side of a passenger's head by a gas injected from an inflator operated in response to detection or prediction of a vehicle collision, and is disposed at the one side of the passenger's head. The left-right chambers are deployed toward the inside in a seat width direction from a seat front side end portion of the front-rear chamber, and are disposed at a seat front side of the passenger's face. The top-end chamber is deployed toward a seat rear side from a seat width direction inside end portion of the left-right chambers, and is disposed at the other side of the passenger's head. The airbag main body is configured such that, in a fully deployed state, the left-right chambers have a curved shape in a plan view.

Description

Technical Field

[0001] The present disclosure relates to a seat-mounted airbag device. Background Art

[0002] Conventionally, there is a known side airbag device that includes an airbag main body that deploys forward from a side portion of a seat back and is positioned to the side of the occupant's upper body (including the head) in the event of a collision from the oblique front of the vehicle, and an airbag protrusion that deploys inward in the seat width direction from the airbag main body and is positioned in front of the occupant's face, with the two being connected to each other by a planar tether (for example, see Japanese Patent Application Laid-Open No. 2006-008105). Summary of the Invention

[0003] However, in a unilaterally deployed seat-mounted airbag device that deploys from the rear side of the occupant's head and is arranged in front of the face, there is a concern that, because the support point on the rear side of the airbag body is offset outward in the seat width direction relative to the load input point generated by the occupant's head when viewed from above, a rotational moment is generated relative to the airbag body in a direction away from the occupant's head, centered around the support point on the rear side, during the occupant's head restraint process in the second half of the collision, causing the occupant's head to fall out of the airbag body.

[0004] As a countermeasure to this concern, a structure has been considered in which the tip chamber of the airbag body, located forward of the occupant's face, is positioned at an acute angle relative to the front and rear chambers of the airbag body, located to the sides of the occupant's head, in a plan view, to impart a counteracting moment to the airbag body. However, bending the tip chamber of the airbag body at an acute angle relative to the front and rear chambers would hinder the smooth flow of gas from the front and rear chambers to the tip chamber, potentially delaying the deployment of the tip chamber and preventing effective head restraint.

[0005] Therefore, an object of the present disclosure is to provide a seat-mounted airbag device that enables gas to flow smoothly from front and rear chambers to a tip chamber of an airbag body.

[0006] In order to achieve the above-mentioned purpose, the seat-mounted airbag device described in the first mode involved in the present disclosure includes an airbag body, wherein the airbag body has front and rear chambers, left and right chambers and a top chamber, the front and rear chambers are passed from one side of the occupant's head and deployed to the front side of the seat by the gas ejected from the inflation device that works based on the detection or prediction of the vehicle collision, and are arranged on one side of the occupant's head, the left and right chambers are deployed from the front side end portions of the front and rear chambers toward the inner side in the seat width direction, and are arranged on the front side of the seat of the occupant's face, the top chamber is deployed from the inner side end portions of the left and right chambers in the seat width direction toward the rear side of the seat, and is arranged on the other side of the occupant's head, and the airbag body is constructed so that, in the deployed state, the left and right chambers become curved when viewed from above.

[0007] According to the first embodiment, when a vehicle collision is detected or predicted, the inflator activates and discharges gas, causing the front and rear chambers to pass to the sides of the occupant's head and deploy toward the front of the seat, positioned to the sides of the occupant's head. Furthermore, the left and right chambers deploy from the front and rear ends of the front and rear chambers toward the inside of the seat width and are positioned toward the front of the occupant's face. Furthermore, the top chamber deploys from the inside ends of the left and right chambers toward the rear of the seat and is positioned to the other side of the occupant's head. The airbag body is constructed so that, when deployed, the left and right chambers form a curved shape when viewed from above. Therefore, compared to a configuration where the left and right chambers form a curved shape at an acute angle when viewed from above, gas can flow smoothly from the front and rear chambers of the airbag body, through the left and right chambers, to the top chamber. This reduces the risk of delayed deployment of the top chamber, effectively restraining the occupant's head.

[0008] In addition, the seat-mounted airbag device described in the second embodiment is that, in the seat-mounted airbag device described in the first embodiment, the airbag body has: an upper surface tether that connects the middle portion in the deployment direction of the upper end portions of the front and rear chambers and the middle portion in the deployment direction of the upper end portion of the top chamber, and covers the upper portion of the space surrounded by the front and rear chambers, the left and right chambers and the top chamber; a lower surface tether that connects the middle portion in the deployment direction of the lower end portions of the front and rear chambers and the lower end portion of the top chamber The upper surface tether is sewn to the upper end portions of the front and rear chambers, the upper end portions of the left and right chambers and the upper end portion of the top chamber, and the lower surface tether is sewn to the lower end portions of the front and rear chambers, the lower end portions of the left and right chambers and the lower end portion of the top chamber, so that when the airbag body is in a state where the airbag body is fully deployed, the left and right chambers are set to a curved shape when viewed from above.

[0009] According to the second embodiment, the upper surface tether connects the deployment-direction intermediate portions of the upper ends of the front and rear chambers and the deployment-direction intermediate portions of the upper end of the top chamber, thereby covering the upper portion of the space enclosed by the front and rear chambers, the left and right chambers, and the top chamber. Furthermore, the lower surface tether connects the deployment-direction intermediate portions of the lower ends of the front and rear chambers and the deployment-direction intermediate portions of the lower end of the top chamber, thereby covering the lower portion of the space enclosed by the front and rear chambers, the left and right chambers, and the top chamber. Furthermore, the upper surface tether is sewn to the upper ends of the front and rear chambers, the upper ends of the left and right chambers, and the upper end of the top chamber, while the lower surface tether is sewn to the lower ends of the front and rear chambers, the lower ends of the left and right chambers, and the lower end of the top chamber. These upper and lower surface tethers ensure that the left and right chambers are curved when viewed from above when the airbag body is fully deployed. Consequently, the left and right chambers can be easily formed into a curved shape when viewed from above.

[0010] Furthermore, a seat-mounted airbag device according to a third aspect is the seat-mounted airbag device according to the second aspect, wherein the lower surface tether has a seat rear side end portion cut away so as to have a smaller area than the upper surface tether when viewed from below.

[0011] According to the third aspect, the lower face tether has its seat rear end portion cut away so that its area is smaller than that of the upper face tether when viewed from above. Therefore, compared to a case where the seat rear end portion of the lower face tether is not cut away, the load on the occupant's neck caused by contact between the lower face tether and the occupant's neck during head restraint can be reduced.

[0012] Furthermore, a seat-mounted airbag device according to a fourth aspect is the seat-mounted airbag device according to the second aspect, wherein the lower surface tether is provided as a tether chamber that is deployed by gas ejected from the inflator.

[0013] According to the fourth aspect, the lower face tether is provided as a tether chamber that is deployed by gas ejected from the inflator. Therefore, compared to a case where the lower face tether is not provided as a tether chamber, the load on the occupant's neck caused by contact between the lower face tether and the occupant's neck during head restraint can be reduced.

[0014] In addition, the seat-mounted airbag device described in the fifth embodiment is a seat-mounted airbag device described in any one of the first to fourth embodiments, wherein the boundary between the left and right chambers and the top chamber is located on an imaginary straight line along the front-rear direction of the seat that passes through the center of gravity of the occupant's head when viewed from above.

[0015] According to the fifth aspect, the boundary between the left and right chambers and the tip chamber is located on an imaginary straight line along the seat front-rear direction that passes through the center of gravity of the occupant's head when viewed from above. This prevents delayed deployment of the tip chamber and also prevents the occupant's head from being pulled out of the airbag body when the occupant's head is restrained.

[0016] In addition, the seat-mounted airbag device described in the sixth embodiment is a seat-mounted airbag device described in any one of the first to fifth embodiments, wherein the support point on the seat side that supports the airbag body is located on an imaginary straight line along the front-rear direction of the seat that passes through the center of gravity of the occupant's head when viewed from above.

[0017] According to the sixth aspect, the seat-side support point for the airbag body is located on an imaginary straight line extending along the seat's fore-aft direction and passing through the center of gravity of the occupant's head when viewed from above. This reduces the offset (distance) in the seat width direction between the point where the occupant's head applies load to the airbag body and the airbag body's support point. This reduces the generation of a rotational moment in the airbag body that would cause it to rotate away from the occupant's head when the occupant's head is restrained, thereby preventing the occupant's head from being dislodged from the airbag body.

[0018] In addition, the seat-mounted airbag device described in the seventh embodiment is a seat-mounted airbag device described in the sixth embodiment, which has a connecting component that extends in the seat width direction when viewed from above and connects the support point on the seat side that supports the airbag body and the seat rear side end portion of the front and rear chambers.

[0019] According to the seventh aspect, a connecting member extending in the seat width direction in a plan view connects the seat-side support point for supporting the airbag main body and the seat rear-side end portion of the front and rear chambers. Therefore, even when a headrest is present, the airbag main body support point can be easily set without interfering with the headrest.

[0020] In addition, the seat-mounted airbag device described in the eighth embodiment is the seat-mounted airbag device described in the seventh embodiment, wherein the seat rear side ends of the front and rear chambers and the ejection outlet of the inflation device are connected together by a connecting component, and the length of the connecting component is longer than the length of the connecting component.

[0021] According to the eighth aspect, the length of the connecting member connecting the seat-rearward end portions of the front and rear chambers to the inflator's discharge port is longer than the length of the coupling member. Therefore, the seat-rearward end portions of the front and rear chambers connected to the inflator's discharge port are prevented from becoming support points for the airbag body.

[0022] In addition, the seat-mounted airbag device described in the ninth embodiment is a seat-mounted airbag device described in any one of the first to eighth embodiments, wherein the airbag body has a head restraint surface tether, the head restraint surface tether connects the head restraint area in the front and rear chambers and the head restraint area in the top chamber, and is formed of a material that is more stretchable than the base fabric of the airbag body.

[0023] According to the ninth aspect, the head restraint surface tether connecting the head restraint areas in the front and rear chambers and the head restraint area in the tip chamber is formed from a material that is more stretchable than the base fabric of the airbag body. Therefore, the occupant's head is held by being wrapped around the head restraint surface tether. This pulls the tip chamber toward the occupant's head, effectively preventing the occupant's head from falling out of the airbag body.

[0024] In addition, the seat-mounted airbag device described in the tenth embodiment is a seat-mounted airbag device described in the first embodiment, wherein the airbag body is composed of an upper surface base cloth and a lower surface base cloth formed into a roughly J-shape when viewed from above or above, and side base cloths sewn around the upper surface base cloth and around the lower surface base cloth at both ends of the seat in the upper and lower directions, respectively.

[0025] According to the tenth aspect, the airbag body comprises an upper surface base fabric and a lower surface base fabric formed into a generally J-shape when viewed from above or below, and side surface base fabrics sewn around the upper and lower surface base fabrics at the vertical ends of the seat, respectively. In other words, the airbag body is not provided with an upper or lower surface tether. Therefore, when the occupant's head is restrained, there is no load on the occupant's neck caused by contact between the lower surface tether and the occupant's neck.

[0026] In addition, the seat-mounted airbag device described in the eleventh embodiment involved in the present disclosure includes an airbag body, wherein the airbag body has front and rear chambers and a top chamber, the front and rear chambers are passed from the side of the occupant's head and deployed to the front side of the seat by the gas ejected from the inflation device that works based on the detection or prediction of the vehicle collision, and are arranged to the side of the occupant's head, the top chamber is deployed from the front side end of the seat of the front and rear chambers toward the inside in the seat width direction, and is arranged to the front side of the seat of the occupant's face, the airbag body is composed of an inner chamber for the occupant's head to contact, and an outer chamber whose length in the deployment direction is formed to be longer than that of the inner chamber and is integrally provided on the outside of the inner chamber, and an excess length portion protruding toward the front side of the seat is formed at the boundary between the front and rear chambers and the top chamber in the outer chamber.

[0027] According to the eleventh embodiment, when a vehicle collision is detected or predicted, the inflator activates and discharges gas, causing the front and rear chambers to pass to the sides of the occupant's head and deploy toward the front of the seat, where they are positioned to the sides of the occupant's head. Furthermore, the tip chamber deploys inward in the seat width direction from the seat-front ends of the front and rear chambers and is positioned in front of the occupant's face. The airbag body comprises an inner chamber, which contacts the occupant's head, and an outer chamber, which is longer in the deployment direction than the inner chamber and integrally positioned outside the inner chamber. Furthermore, an excess length portion is formed at the boundary between the front and rear chambers and the tip chamber in the outer chamber, protruding toward the front of the seat. This allows gas to flow more smoothly from the front and rear chambers of the airbag body to the tip chamber, compared to a case where this excess length portion is not formed. This prevents delayed deployment of the tip chamber and effectively restrains the occupant's head. Furthermore, since the airbag body is not provided with an upper surface tether and a lower surface tether, when the occupant's head is restrained, there is no load on the occupant's neck caused by contact between the lower surface tether and the occupant's neck.

[0028] As described above, according to the present disclosure, in a seat-mounted airbag device, gas can be smoothly flowed from the front and rear chambers of the airbag body to the tip chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a side view showing the seat-mounted airbag device according to the first embodiment in a deployed state.

[0030] Figure 2 It is a plan view showing the seat-mounted airbag device according to the first embodiment in a deployed state.

[0031] Figure 3 This is an enlarged plan view showing the state of the seat-mounted airbag device according to the first embodiment before deployment, with one portion thereof ruptured.

[0032] Figure 4 It is an enlarged plan view showing a state in which an airbag main body of the seat-mounted airbag device according to the first embodiment has been deployed.

[0033] Figure 5 It is an enlarged bottom view showing the state in which the airbag main body of the seat-mounted airbag device according to the first embodiment has been deployed.

[0034] Figure 6 It is a development view showing a modified example of the airbag main body in the seat-mounted airbag device according to the first embodiment.

[0035] Figure 7 It is a perspective view showing a state in which an airbag main body of a seat-mounted airbag device according to a second embodiment has been deployed.

[0036] Figures 8A to 8C It is a plan view showing a process of restraining an occupant's head by the seat-mounted airbag device according to the second embodiment.

[0037] Figure 9 Graph showing load-displacement characteristics (FS characteristics) when the occupant's head is restrained by the seat-mounted airbag device according to the second embodiment.

[0038] Figure 10 It is a plan view showing a state where an airbag main body of a seat-mounted airbag device according to a third embodiment has been deployed.

[0039] Figure 11 It is an exploded view showing the structure of an airbag main body in a seat-mounted airbag device according to a third embodiment.

[0040] Figure 12 It is a plan view showing a state where an airbag main body has been deployed in a seat-mounted airbag device according to a fourth embodiment.

[0041] Figure 13 It is an exploded view showing the structure of an airbag main body in a seat-mounted airbag device according to a fourth embodiment.

[0042] Figure 14 This is a plan cross-sectional view showing a partially enlarged structure of an airbag main body in a seat-mounted airbag device according to a fourth embodiment. DETAILED DESCRIPTION

[0043] The following describes the embodiments of the present disclosure in detail based on the accompanying drawings. For ease of explanation, the arrow UP, as indicated in the respective drawings, indicates the seat's upward direction, the arrow FR indicates the seat's forward direction, and the arrow RH indicates the seat's right direction. Therefore, in the following description, when up / down, front / back, or left / right directions are mentioned unless otherwise specified, they are considered to represent the vehicle seat's up / down, front / back, or left / right directions. The left / right direction is synonymous with the seat's width direction.

[0044] like Figures 1 to 3As shown, a seat-mounted airbag device (hereinafter simply referred to as "airbag device") 30 according to this embodiment is installed inside a housing portion 20 that constitutes a headrest 16 of a vehicle seat 10 serving as a rear seat of the vehicle. Therefore, although the vehicle seat 10 according to this embodiment is described as a rear seat, the airbag device 30 may also be installed in a front seat.

[0045] In addition, as an example, the rear seat is set as the left side window glass 18 (refer to Figure 3 ) side rear seat, as described later, the airbag body 32 will be described as an example of a case where it passes through and deploys between the head Ph of the occupant P on the side window glass 18 and the head of the occupant (not shown) on the center seat side. However, the airbag body 32 may also pass through and deploy between the side window glass 18 and the head Ph of the occupant P. Furthermore, as an example, the "occupant P" in this embodiment refers to an occupant corresponding to AM50 (50th percentile of adult males in the United States) of the WorldSID (World Side Impact Dummy).

[0046] <First embodiment>

[0047] First, the airbag device 30 according to the first embodiment will be described. Figure 1 、 Figure 2 As shown, the vehicle seat 10 includes a seat cushion 12 on which the occupant P sits (supporting the buttocks and thighs of the occupant P), a seat back 14 supporting the back of the occupant P, and a headrest 16 supporting the head Ph of the occupant P.

[0048] like Figure 3 As shown, the headrest 16 includes a block-shaped main body portion 16A that is disposed in a liftable manner at the center in the seat width direction of the upper end portion of the seat back 14. Specifically, a pair of left and right cylindrical headrest supports (not shown) are disposed at the center in the seat width direction of the lower surface of the main body portion 16A.

[0049] Each headrest support is inserted into a pair of left and right, substantially cylindrical headrest posts 26 located at the center of the seat width direction at the upper end of the seatback 14, allowing it to be raised and lowered and fixed at multiple predetermined positions. This allows the height of the headrest 16 to be adjusted to match the position of the head Ph of the occupant P. The headrest 16 includes a shell portion 20 extending continuously from the rear of the main body portion 16A to the left and right sides.

[0050] The shell portion 20 is formed in a generally U-shaped configuration with the front side open when viewed from above. The main body 16A of the headrest 16 is disposed within the shell portion 20 with virtually no space between them. Furthermore, the front end surfaces of the left and right side portions 24 extending in the front-to-back direction of the shell portion 20 (the outer surfaces of the front wall 20F) are substantially flush with the front surface of the main body 16A.

[0051] In addition, the left and right outer side walls 20A (side portions 24) and the rear wall 20B of the housing portion 20 are formed by a resin cover member 22 formed into a substantially U-shaped shape when viewed from above. Figure 1 、 Figure 2 ), the lower wall (omitted in the figure), the front wall 20F and the inner peripheral wall 20C opposite to the main body 16A are constructed in a manner including a polyurethane foam plastic (omitted in the figure) set to a predetermined thickness, and the cover part 22 and the outer surface of the polyurethane foam plastic are covered integrally with the skin material 21.

[0052] A predetermined space S (including a housing portion S1 and a placement portion S2, described below) is formed within the housing portion 20. The airbag main body 32 of the airbag device 30 is housed in the housing portion S1 formed within a side portion 24R of the housing portion 20 on the side opposite the side window glass 18 (the right side, which is the center seat side, in the illustration). The structure of the airbag main body 32 will be described in detail later.

[0053] An inflator 28 is disposed in a rear portion S of the space S formed in the housing 20, specifically, in a placement portion S2 located rearward of the main body 16A in plan and side views. The inflator 28 is formed in a substantially bottomed cylindrical shape, and its outer periphery is supported on a reaction plate (not shown) formed in a frame shape via a retainer (not shown) so that its axis is arranged in the front-rear direction.

[0054] The reaction plate is fixed to a seat back frame (not shown) via a bracket (not shown), for example, and is configured to receive the reaction force transmitted from the airbag body 32 deployed forward via the inflator 28. The reaction plate and retainer are also disposed in the arrangement portion S2.

[0055] The inflator 28 is electrically connected to the vehicle's airbag ECU (not shown). Furthermore, a detection device (not shown) such as an acceleration sensor installed on the vehicle is also electrically connected to the airbag ECU. Therefore, when the detection device detects a vehicle collision, the inflator 28 is activated via the airbag ECU, instantly discharging gas.

[0056] The inflator 28 may not be configured to be activated by detecting a vehicle collision, but may be configured to be activated by predicting a vehicle collision using a collision prediction sensor or the like (not shown).

[0057] The discharge port of the inflator 28 and the rear end portion 34B of the airbag main body 32 (front and rear chambers 34) are connected by a connecting member 31. Specifically, the rear end portion (one end portion) of the connecting member 31 is connected to the discharge port of the inflator 28, and the front end portion (the other end portion) of the connecting member 31 is connected to the rear end portion 34B of the airbag main body 32 (front and rear chambers 34).

[0058] like Figure 1 、 Figure 2 As shown, the airbag device 30 includes an airbag body 32, which is inflated by an inflator 28 (see FIG. Figure 3 ) ejects gas, thereby deploying the airbag body 32 from the rear side (specifically, the right rear side) of the head Ph of the occupant P sitting on the vehicle seat 10 toward the front side.

[0059] The airbag body 32 includes a front and rear chamber 34, a left and right chamber 35, and a tip chamber 36. The front and rear chamber 34 passes through the right side (one side) of the occupant P's head Ph and deploys forward. It is positioned to the right of the occupant P's head Ph (between the occupant P's head Ph on the side window glass 18 side and the occupant's head on the center seat side). The left and right chambers 35 deploy inward in the seat width direction from the front end of the front and rear chamber 34 and are positioned in front of the occupant P's face. The tip chamber 36 deploys rearward from the seat width direction inner end of the left and right chamber 35 and is positioned to the left side (the other side) of the occupant P's head Ph. In other words, the airbag body 32 is curved into a substantially "J" shape when viewed from below, thereby restraining at least the occupant P's head Ph.

[0060] Moreover, if Figure 4 、 Figure 5As shown, the airbag body 32 has an upper surface tether 37 and a lower surface tether 38. The upper surface tether 37 connects the middle portion 34U in the deployment direction in the upper end portion of the front and rear chambers 34 and the middle portion 36U in the deployment direction in the upper end portion of the top chamber 36, and covers the upper portion of the space surrounded by the front and rear chambers 34, the left and right chambers 35 and the top chamber 36. The lower surface tether 38 connects the middle portion 34D in the deployment direction in the lower end portion of the front and rear chambers 34 and the middle portion 36D in the deployment direction in the lower end portion of the top chamber 36, and covers the lower portion of the space surrounded by the front and rear chambers 34, the left and right chambers 35 and the top chamber 36.

[0061] If we explain it more specifically, Figure 4 As shown, the upper surface tether 37 is formed into a roughly trapezoidal shape having a straight rear end edge portion 37A that connects the middle portion 34U in the deployment direction in the upper end portion of the front and rear chambers 34 and the middle portion 36U in the deployment direction in the upper end portion of the top chamber 36 when the airbag body 32 is inflated and deployed and when viewed from above.

[0062] Moreover, the peripheral portion of the upper surface tether 37, except for its rear end edge portion 37A (rear side end portion), is installed at the upper end portions of the front and rear chambers 34, the upper end portions of the left and right chambers 35, and the upper end portion of the top chamber 36 by sewing from the middle portion 34U in the expansion direction in the upper end portions of the front and rear chambers 34, through the upper end portions of the left and right chambers 35 to the middle portion 36U in the expansion direction in the upper end portion of the top chamber 36.

[0063] Likewise, if Figure 5 As shown, the lower surface tether 38 is formed to have a roughly trapezoidal shape having a rear end edge portion 38A described later that connects the middle portion in the deployment direction (the middle portion close to the left and right chambers 35) 34D in the lower end portion of the front and rear chambers 34 and the middle portion in the deployment direction 36D in the lower end portion of the top chamber 36 when the airbag body 32 is inflated and deployed and when viewed from above.

[0064] Moreover, the peripheral portion of the lower surface tether 38, except for its rear end edge portion 38A (rear side end portion), is installed at the lower end portions of the front and rear chambers 34, the lower end portions of the left and right chambers 35, and the lower end portion of the top chamber 36 by sewing from the middle portion 34D in the expansion direction in the lower end portions of the front and rear chambers 34 through the lower end portions of the left and right chambers 35 to the middle portion 36D in the expansion direction in the lower end portion of the top chamber 36.

[0065] By means of the upper surface tether 37 and the lower surface tether 38, when the airbag body 32 is deployed, the left and right chambers 35 are curved with a small curvature (no sharp angle) when viewed from above. Figure 5 As shown, when viewed from above, the lower surface tether 38 has its rear side end portion significantly cut off so that its area becomes smaller than that of the upper surface tether 37, specifically, becomes approximately half the size of the upper surface tether 37, thereby forming a rear end edge portion 38A that does not protrude toward the occupant P side.

[0066] In addition, if Figure 2 、 Figure 3 As shown, the boundary 35A between the left and right chambers 35 and the top chamber 36 is located on an imaginary straight line K extending along the front-back direction and passing through the center of gravity of the head Ph of the occupant P in a plan view. The support point 40 on the vehicle seat 10 side that supports the airbag body 32 is also located on this imaginary straight line K. In other words, the support point 40 located on this imaginary straight line K is provided on the rear side of the headrest 16 (main body 16A) within the housing 20.

[0067] The support point 40 is preferably provided on the imaginary straight line K, but may be provided so as to be offset in the seat width direction (distance L: see FIG. 1 ) from the load input point G to the airbag body 32 by the head Ph of the occupant P (the contact point between the head Ph of the occupant P and the tip chamber 36). Figure 2 ) at a smaller position.

[0068] The imaginary line K assumes that the occupant P is seated at the center of the seat cushion 12 of the vehicle seat 10 in the seat width direction. Therefore, the imaginary line K can also be referred to as a centerline along the front-to-back direction that passes through the center of the seat width direction of the vehicle seat 10 in a plan view. Furthermore, due to the upper surface tether 37 and the lower surface tether 38, the top chamber 36 is inclined at an angle of, for example, 45 degrees relative to the imaginary line K in a plan view.

[0069] Furthermore, a pair of upper and lower connecting members 41 are provided in the housing portion 20 to connect the support point 40 and the rear end portion 34B of the front and rear chambers 34. The connecting members 41 extend in the seat width direction when viewed from above, and one end portion of each connecting member 41 in the extending direction is fixed to the support point 40, and the other end portion of each connecting member 41 in the extending direction is attached to the rear end portion 34B of the front and rear chambers 34 by sewing or the like (see FIG. 1 ). Figure 6 ).

[0070] Thus, although the other end of the connecting member 41 in the extension direction and the front end (other end) of the connecting member 31 are connected to the rear side end 34B of the front-rear chamber 34, the extension direction of the connecting member 41 and the extension direction of the connecting member 31 are substantially perpendicular to each other when viewed from above when the airbag body 32 is deployed. Moreover, the length of the connecting member 31 is longer than that of the connecting member 41 (see FIG. Figure 2 、 Figure 3 ).

[0071] In addition, if Figure 3 As shown, the airbag body 32 is rolled outwardly into a roll-like shape with the vertical direction as the axial direction (in a plan view, with a rolled-out portion 32A on the outside in the seat width direction), and is housed in the housing portion S1 formed in the side portion 24R. Furthermore, a pleated portion 32B is formed continuously with the rolled-out portion 32A on the upstream side in the deployment direction.

[0072] Specifically, the airbag body 32 is housed in the housing portion S1 with the accordion portion 32B continuously folded into an accordion shape from the outer rolled portion 32A toward the upstream side in the deployment direction. Therefore, when the airbag body 32 is deployed forward from the side portion 24R by the gas ejected from the inflator 28, passing to the right of the head Ph of the occupant P, the accordion portion 32B is first unwound and deployed, followed by the outer rolled portion 32A.

[0073] In addition, although Figure 3 The illustrated accordion portion 32B is formed in two groups when the portion folded in two is set as one group, but the present invention is not limited thereto. The accordion portion 32B only needs to be formed in a plurality of groups, and may be formed in three or more groups.

[0074] Furthermore, the front wall 20F constituting the front end surface of the side portion 24R is ruptured, along with a portion of the front wall 20F side of the upper wall 20U, in a linear shape, for example, along the vertical direction when viewed from the front, as the airbag body 32 is deployed. The ruptured portion is preferably the seat width direction inner end portion 20N of the front wall 20F.

[0075] When the ruptured portion is the seat width direction inner end portion 20N of the front wall 20F (for example, when a fragile portion that is easily ruptured is formed at the seat width direction inner end portion 20N of the front wall 20F), the front wall 20F is opened with the seat width direction outer end portion 20T serving as a hinge portion.

[0076] Next, the operation of the airbag device 30 according to the first embodiment having the above-described configuration will be described.

[0077] When the detection device detects a frontal collision of the vehicle, the inflator 28 is activated to instantaneously eject gas into the interior of the airbag body 32. When the gas is ejected into the interior of the airbag body 32, the front wall 20F of the side portion 24R and a portion of the front wall 20F side of the upper wall 20U are ruptured due to the deployment of the airbag body 32 (due to being pressed from the inside by the airbag body 32).

[0078] The airbag body 32 then passes from the side portion 24R to the right of the head Ph of the occupant P (the gap between the head Ph of the occupant P on the side window glass 18 side and the head of the occupant on the center seat side) and deploys forward. Specifically, the airbag body 32 first unrolls and deploys the accordion portion 32B folded into an accordion shape, and then unrolls and deploys the outer roll portion 32A rolled outward into a roll shape.

[0079] Here, it is known that, generally speaking, a pleated shape unwinds more quickly than a rolled shape (a pleated shape has less resistance during deployment than a rolled shape). Therefore, compared to an airbag body 32 having only an outer roll portion 32A, an airbag body 32 having an outer roll portion 32A and an pleated portion 32B in this order from the downstream side in the deployment direction can deploy forward more quickly.

[0080] When the front and rear chambers 34 are inflated and deployed, and are positioned to the right of the head Ph of the occupant P, gas flows from the front ends of the front and rear chambers 34 into the left and right chambers 35, causing the left and right chambers 35 to inflate and deploy inward in the seat width direction, and to be positioned in front of the face of the occupant P. Furthermore, gas flows from the left and right chambers 35 into the top chamber 36, causing the top chamber 36 to deploy rearward from the seat width direction inside ends of the left and right chambers 35, and to be positioned to the left of the head Ph of the occupant P.

[0081] Here, the airbag body 32 is configured by the upper surface tether 37 and the lower surface tether 38 so that, in the fully deployed state, the left and right chambers 35 are curved in a plan view. Therefore, compared to a configuration in which the left and right chambers 35 are curved at acute angles in a plan view, gas can flow more smoothly from the front and rear chambers 34 of the airbag body 32 through the left and right chambers 35 to the tip chamber 36.

[0082] This can suppress or prevent delays in the deployment of the top chamber 36, allowing the airbag body 32 to deploy as planned. Furthermore, as described above, since the left and right chambers 35 are curved in a plan view by the upper surface tethers 37 and the lower surface tethers 38, this curved shape can be easily formed.

[0083] In this manner, the airbag body 32 (the front and rear chambers 34, the left and right chambers 35, and the top chamber 36) is deployed smoothly and as intended, thereby effectively restraining at least the head Ph of the occupant P seated on the vehicle seat 10. In other words, the airbag body 32 effectively prevents at least the head Ph of the occupant P from moving forward due to inertial force.

[0084] Furthermore, as described above, since the airbag body 32 unwinds the outwardly rolled portion 32A and deploys forward, there is no possibility that the face of the occupant P will be injured by the airbag body 32 when the airbag body 32 deploys. Furthermore, by adopting a structure in which the front wall 20F opens with the seat width direction outer end portion 20T serving as a hinge portion when the airbag body 32 deploys, the airbag body 32 can prevent the deployed front wall 20F from coming into contact with the head Ph of the occupant P.

[0085] Furthermore, although the lower face tether 38 is positioned at the neck of the occupant P, its rear end portion is cut away to form a rear end edge portion 38A so as to reduce its area compared to the upper face tether 37 when viewed from above. Therefore, compared to a case where the rear end portion of the lower face tether 38 is not cut away, when restraining the head Ph of the occupant P, which tends to move forward due to inertial force, the lower face tether 38 does not interfere with (does not hit) the neck of the occupant P. Even if it does interfere (even if it hits), the load on the neck of the occupant P caused by contact with the neck of the occupant P can be reduced.

[0086] That is, the lower face tether 38 can reduce the damage to the neck of the occupant P even when the head Ph of the occupant P moves forward due to inertial force and is restrained by the airbag body 32. Furthermore, because the upper face tether 37 is located above the head Ph of the occupant P, it does not interfere with (does not collide with) the head Ph of the occupant P even when the head Ph of the occupant P moves forward due to inertial force and is restrained by the airbag body 32.

[0087] Furthermore, the boundary 35A between the left and right chambers 35 and the tip chamber 36 is located on an imaginary straight line K extending along the front-rear direction and passing through the center of gravity of the head Ph of the occupant P when viewed from above. Therefore, while suppressing delays in deployment of the tip chamber 36, the head Ph of the occupant P can be more effectively restrained during head restraint, thereby suppressing the head Ph of the occupant P from coming out of the airbag body 32.

[0088] Furthermore, the support point 40 on the vehicle seat 10 side that supports the airbag body 32 is located on an imaginary straight line K extending along the front-rear direction and passing through the center of gravity of the head Ph of the occupant P when viewed from above. Consequently, the seat widthwise offset (distance L) between the load input point G of the occupant P's head Ph and the support point 40 of the airbag body 32 can be reduced. Consequently, when the occupant P's head is restrained, the generation of a rotational moment in the airbag body 32 that would rotate away from the occupant P's head Ph can be suppressed, thereby preventing the occupant P's head Ph from being dislodged from the airbag body 32.

[0089] Furthermore, a connecting member 41 extending in the seat width direction in a plan view connects a support point 40 supporting the airbag main body 32 and the rear end portion 34B of the front-rear chamber 34. Therefore, even if a headrest 16 is present, the support point 40 of the airbag main body 32 can be easily set so as not to interfere with the headrest 16 (by bypassing the headrest 16).

[0090] Furthermore, the length of the connecting member 31 connecting the rear end portion 34B of the front-rear chamber 34 and the discharge port of the inflator 28 is longer than the length of the coupling member 41. Therefore, the rear end portion 34B of the front-rear chamber 34 connected to the discharge port of the inflator 28 can be prevented from becoming the support point 40 of the airbag main body 32.

[0091] (Change example)

[0092] In addition, if Figure 6 As shown, the lower face tether 38 may be provided as a tether chamber 38B that is deployed by gas ejected from the inflator 28. When the lower face tether 38 is provided as the tether chamber 38B, the load on the neck of the occupant P caused by the contact between the lower face tether 38 and the neck of the occupant P when the head of the occupant P is restrained can be more effectively reduced compared to a case where the lower face tether 38 is not provided as the tether chamber 38B.

[0093] In addition, in this case, Figure 6 As shown, the lower face tether 38 is preferably formed in a shape with its rear end portion cut away (e.g., a shape such as the rear end edge portion 38A). This further reduces the load on the neck of the occupant P caused by the contact between the lower face tether 38 and the neck of the occupant P when the head of the occupant P is restrained, thereby further reducing the damage to the neck of the occupant P.

[0094] Furthermore, the upper face tether 37 may be provided as a tether chamber 37B that is deployed by gas ejected from the inflator 28. When the upper face tether 37 is also provided as the tether chamber 37B, the tip of the tip chamber 36 can be deformed so as to approach the front and rear chambers 34 when the head of the occupant P is restrained. This can more effectively prevent the head Ph of the occupant P from falling out of the airbag body 32.

[0095] <Second embodiment>

[0096] Next, an airbag device 30 according to a second embodiment will be described. Components equivalent to those in the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof (including common functions) are omitted as appropriate.

[0097] like Figure 7 As shown, the airbag body 32 of the airbag device 30 involved in the second embodiment differs from the above-mentioned first embodiment only in that it has a head restraint surface tether 39 and does not provide an upper surface tether 37 and a lower surface tether 38. The head restraint surface tether 39 connects the head restraint area in the front and rear chambers 34 and the head restraint area in the top chamber 36, and is formed of a material that is more stretchable than the base fabric of the airbag body 32.

[0098] According to this head restraint with face tether 39, as Figures 8A to 8C As shown, the head Ph of the occupant P, which is trying to move forward due to inertial force, is retained by being wound around the head restraint surface tether 39. As a result, the distal end chamber 36 is pulled toward the head Ph of the occupant P, and thus the head Ph of the occupant P can be more effectively prevented from falling out of the airbag body 32.

[0099] Furthermore, since the head restraint face tether 39 extends forward, the forward movement of the head Ph of the occupant P is not restricted, and the left and right chambers 35 and the left and right chambers 35 can be compressed in the front-to-back direction. This achieves low-load and high-stroke FS characteristics.

[0100] exist Figure 9 The FS characteristics are shown in Figure 2. Figure 9 As shown by the dotted line in the figure, if the head restraining surface tether 39 is not provided, the load acting on the head Ph of the occupant P increases sharply because the portion of the left and right chambers 35 in the top chamber 36 and the left and right chambers 35 cannot be squeezed in the front-rear direction.

[0101] However, if Figure 9As shown by the solid line in FIG, when the head restraint face tether 39 is provided, the face tether 39 extends forward, thereby compressing a portion of the left and right chambers 35 in the distal chamber 36 and the left and right chambers 35 in the front-rear direction. This absorbs the load (energy) acting on the head Ph and increases the forward stroke. Therefore, compared to a case where the head restraint face tether 39 is not provided, the load acting on the head Ph can be reduced.

[0102] <Third embodiment>

[0103] Next, an airbag device 30 according to a third embodiment will be described. Components equivalent to those in the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof (including common functions) are omitted as appropriate.

[0104] like Figure 10 、 Figure 11 As shown, the airbag body 42 of the airbag device 30 according to the third embodiment is composed of an upper surface base fabric 44 and a lower surface base fabric 46 formed into a substantially "J" shape when viewed from below, and side surface base fabrics 48 having both ends sewn (three-dimensionally sewn) in the upper and lower directions around the upper and lower surface base fabrics 44 and 46, respectively. In other words, the airbag body 32 is not provided with an upper surface tether 37 or a lower surface tether 38.

[0105] Therefore, when the head of the occupant P is restrained, there is no load on the neck of the occupant P caused by the lower surface tether 38 contacting the neck of the occupant P. In addition, a tether 50 is sewn at the vertical center of the interior of the airbag body 42 (see FIG. Figure 11 ), the tether 50 limits the thickness of the central portion of the airbag body 42 in the vertical direction so that the thickness does not become thicker than required.

[0106] In addition, when the airbag main body 42 is deployed from the left rear side to the front side of the head Ph of the occupant P sitting on the vehicle seat 10, the airbag main body 42 is composed of an upper surface base cloth 44 and a lower surface base cloth 46 formed into a roughly "J" shape when viewed from above, and a side base cloth 48 whose two ends in the upper and lower directions are sewn (three-dimensionally sewn) around the upper surface base cloth 44 and the lower surface base cloth 46, respectively.

[0107] <Fourth embodiment>

[0108] Finally, an airbag device 30 according to a fourth embodiment will be described. Components equivalent to those in the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof will be omitted as appropriate.

[0109] like Figures 12 to 14 As shown, the airbag body 52 of the airbag device 30 involved in the fourth embodiment has a front and rear chamber 54 and a top chamber 56. The front and rear chamber 54 passes from the right side (lateral side) of the head Ph of the occupant P and is deployed toward the front side, and is arranged to the right side of the head Ph of the occupant P (between the head Ph of the occupant P on the side of the side window glass 18 and the head of the occupant on the side of the center seat), and the top chamber 56 is deployed from the front side end of the front and rear chamber 54 toward the inside in the seat width direction and is arranged in front of the face of the occupant P.

[0110] The airbag body 52 is composed of an inner chamber 53 with which the head Ph of the occupant P comes into contact, and an outer chamber 55 which is formed to be longer in the deployment direction than the inner chamber 53 and is integrally provided on the outer side of the inner chamber 53. Specifically, the inner chamber 53 includes front and rear chambers 54 and a top chamber 56, and the outer chamber 55 also includes front and rear chambers 54 and a top chamber 56.

[0111] Furthermore, an excess length portion 57 is formed at the boundary portion 55A between the front and rear chambers 54 and the top chamber 56 in the outer chamber 55 so as to protrude forward when deployed. Figure 14 As shown, the airbag body 52 is constructed in the following manner, that is, when the excess length portion 57 is folded, the outer chamber 55 is overlapped on the inner chamber 53, the outer peripheral edge portion of the outer chamber 55 except the excess length portion 57 and the outer peripheral edge portion of the inner chamber 53 are sewn together, and the outer peripheral edge portions of the excess length portion 57 are sewn together.

[0112] Next, the operation of the airbag device 30 according to the fourth embodiment having the above-described structure will be described. The description of the operations common to those of the first embodiment will be omitted as appropriate.

[0113] When the detection device detects that the vehicle has undergone a front surface collision, the inflation device 28 operates and ejects gas, so that the front and rear chambers 54 pass through the right side of the occupant P's head Ph and expand toward the front side, and are arranged on the right side of the occupant P's head Ph, and the top chamber 56 expands from the front side end of the front and rear chambers 54 toward the inner side in the seat width direction, and is arranged on the front side of the occupant P's face.

[0114] Here, the airbag body 52 is composed of an inner chamber 53 with which the head Ph of the occupant P contacts, and an outer chamber 55, which is formed to be longer in the deployment direction than the inner chamber 53 and is integrally provided on the outer side of the inner chamber 53. Furthermore, an excess length portion 57 is formed at a boundary 55A between the front and rear chambers 54 and the tip chamber 56 of the outer chamber 55, protruding forward.

[0115] Therefore, compared to a case where the excess length portion 57 is not formed, gas can flow smoothly from the front and rear chambers 54 of the airbag body 52 to the tip chamber 56. Consequently, it is possible to suppress delays in deployment of the tip chamber 56 and effectively restrain the head Ph of the occupant P. Furthermore, since the airbag body 52 is not provided with the upper face tether 37 or the lower face tether 38, there is no load on the neck of the occupant P caused by contact between the lower face tether 38 and the neck of the occupant P when the head of the occupant P is restrained.

[0116] While the seat-mounted airbag device 30 according to this embodiment has been described above based on the accompanying drawings, the seat-mounted airbag device 30 according to this embodiment is not limited to the illustrated figures and can be appropriately modified within the scope of the present disclosure. For example, the seat-mounted airbag device 30 according to this embodiment can also be a combination of the structures of various embodiments.

[0117] In addition, the connecting component 41 that connects the rear side end 34B of the front and rear chambers 34 in the airbag body 32 and the support point 40 is not limited to a structure arranged in a pair of upper and lower parts. As long as it is a structure that can appropriately support the rear side end 34B of the front and rear chambers 34, it can also be provided with only one.

[0118] Explanation of symbols

[0119] 28…Inflatable device;

[0120] 30…Airbag devices (seat-mounted airbag devices);

[0121] 31…connecting parts;

[0122] 32…Airbag body;

[0123] 34…Anterior and posterior chambers;

[0124] 35…left and right chambers;

[0125] 35A…Boundary Department;

[0126] 36…apical chamber;

[0127] 37…Upper face tether;

[0128] 38 lower surface tether

[0129] 38A rear end edge portion (seat rear side end portion)

[0130] 38B tether chamber

[0131] 39 head restraint surface tether

[0132] 40 support point

[0133] 41 link member

[0134] 42 airbag main body

[0135] 44 upper surface base fabric

[0136] 46 lower surface base fabric

[0137] 48 side surface base fabric

[0138] 52 airbag main body

[0139] 53 inner side chamber

[0140] 55 outer side chamber

[0141] 57 excess length portion

[0142] K imaginary straight line

[0143] P occupant

[0144] Ph head

Claims

1. A seat-mounted airbag device, wherein: The airbag body includes a front and rear chamber, a left and right chamber, and a top chamber. The front and rear chambers are deployed from one side of the occupant's head and deployed in front of the seat by gas ejected from an inflator that operates based on detection or prediction of a vehicle collision, and are arranged on one side of the occupant's head. The left and right chambers are deployed from the front-side end portions of the front and rear chambers toward the inner side in the seat width direction, and are arranged on the front side of the seat with respect to the occupant's face. The top chamber is deployed from the inner side end portions of the left and right chambers in the seat width direction toward the rear side of the seat, and is arranged on the other side of the occupant's head. The airbag body is configured such that, in a fully deployed state, the left and right chambers are curved in a plan view. The airbag body comprises: an upper surface tether that connects an intermediate portion in the deployment direction of the upper end portions of the front and rear chambers and an intermediate portion in the deployment direction of the upper end portion of the top chamber, and covers an upper portion of a space enclosed by the front and rear chambers, the left and right chambers, and the top chamber; The lower surface tether connects the middle portion of the lower end portions of the front and rear chambers in the deployment direction and the middle portion of the lower end portion of the top chamber in the deployment direction, and covers the lower portion of the space surrounded by the front and rear chambers, the left and right chambers, and the top chamber. By sewing the upper surface tether to the upper ends of the front and rear chambers, the upper ends of the left and right chambers, and the upper end of the top chamber, and sewing the lower surface tether to the lower ends of the front and rear chambers, the lower ends of the left and right chambers, and the lower end of the top chamber, the left and right chambers are formed into a curved shape when viewed from above when the airbag body is deployed. The lower surface tether has a seat rear side end portion cut away so that its area is smaller than that of the upper surface tether when viewed from below.

2. The seat-mounted airbag device according to claim 1, wherein: The lower surface tether is provided as a tether chamber that is deployed by the gas ejected from the inflator.

3. The seat-mounted airbag device according to claim 1 or 2, wherein: The boundary between the left and right chambers and the top chamber is located on an imaginary straight line along the seat front-rear direction that passes through the center of gravity of the occupant's head in a plan view.

4. The seat-mounted airbag device according to claim 1 or 2, wherein: A support point on the seat side that supports the airbag body is located on an imaginary straight line along the seat front-rear direction that passes through the center of gravity of the occupant's head in a plan view.

5. The seat-mounted airbag device according to claim 4, wherein: A connecting member is provided that extends in the seat width direction in a plan view and connects a seat-side support point that supports the airbag body and a seat rear-side end portion of the front-rear chamber.

6. The seat-mounted airbag device according to claim 5, wherein: The seat rear side end portion of the front and rear chambers and the discharge port of the inflator are connected together by a connecting member. The length of the connecting member is longer than the length of the coupling member.

7. The seat-mounted airbag device according to claim 1 or 2, wherein: The airbag body includes a head restraint surface tether that connects head restraint regions in the front and rear chambers and a head restraint region in the tip chamber and is formed of a material that is more stretchable than a base fabric of the airbag body.

8. The seat-mounted airbag device according to claim 1, wherein: The airbag body is composed of an upper surface base fabric and a lower surface base fabric formed into a substantially J-shape when viewed from above or below, and side surface base fabrics sewn around the upper surface base fabric and the lower surface base fabric at both ends of the seat in the vertical direction.

Images