Airbag device

Abstract

[Problem] To provide an airbag device capable of optimally controlling the deployment speed and the deployment behavior of an airbag that can restrict the body portion and the head portion of an occupant. [Solution] The present invention provides an airbag device accommodated in a vehicular seat, the airbag device comprising: an inflator that generates expansion gas; and an airbag that protects an occupant by deploying from a side section of the vehicular seat. The airbag includes: a head portion protection cushion that deploys at least on the head-side section of the occupant; and a side cushion that deploys at a region from a side section of the shoulder portion to the waist portion of the occupant. The inflator comprises a gas discharge part and is provided so that at least the gas discharge part is accommodated inside the side cushion. A diffuser is provided inside the airbag so as to cover the surroundings of the gas discharge part of the inflator. The diffuser comprises: a first opening section communicating with the head portion protecting cushion; and a second opening section communicating with the side cushion. In addition, the maximum projection area of the first opening section is set to be greater than that of the second opening section when the opening sections are in a maximally open state.

Description

[Technical field]

[0001] The present invention relates to an airbag device mounted on a vehicle, and more particularly to an airbag device capable of appropriately controlling the deployment behavior of an airbag. [Background technology]

[0002] It is well known that one or more airbag devices are provided in a vehicle to protect the occupant in the event of a vehicle accident. Airbag devices come in various forms, such as a driver airbag device that deploys near the center of the steering wheel to protect the driver, a curtain airbag device that deploys downward inside the window to protect the occupant in the event of a lateral impact or rollover or overturning accident, and a side airbag device that deploys on the side of the occupant (the side of the seat) to protect the occupant in the event of a lateral impact.

[0003] A side airbag device restrains the lateral movement of an occupant by using an airbag that deploys forward from the seat. For example, an invention disclosed in Patent Document 1 has been proposed that is configured to protect not only the torso of an occupant, but also the head.

[0004] However, in conventional airbag devices such as the airbag device described in Patent Document 1, it is difficult to appropriately adjust the deployment speed of the airbag for each part of the occupant to be restrained, which may result in a delay in restraining important parts of the occupant. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2019-137307 A Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in consideration of the above-mentioned circumstances, and has an object to provide an airbag device that can optimally control the deployment speed and deployment behavior of an airbag that can restrain the torso and head of an occupant. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides an airbag device accommodated in a vehicle seat, comprising: an inflator that generates inflation gas; and an airbag that protects an occupant by deploying from a side of the vehicle seat. The airbag includes a head protection cushion that deploys at least on the side of the occupant's head, and a side cushion that deploys on the side of the occupant's shoulder to waist. The inflator has a gas discharge portion, and is provided so that at least the gas discharge portion is accommodated inside the side cushion. A diffuser is provided inside the airbag so as to cover the periphery of the gas discharge portion of the inflator. The diffuser has a first opening that communicates with the head protection cushion and a second opening that communicates with the side cushion. The first opening and the second opening are each set so that the maximum projected area of ​​the first opening is larger than that of the second opening when fully opened.

[0008] Here, the "maximum projected area" refers to the area of ​​a plane perpendicular to the longitudinal axis when the first opening is the upper opening of a cylindrical diffuser, for example. Also, when the first opening is an obliquely cut shape at the top of a cylindrical diffuser, the reference is not the plane perpendicular to the longitudinal axis but the plane parallel to the inclination angle of the opening.

[0009] The diffuser is molded in a cylindrical shape having an upper opening and a lower opening, the first opening corresponds to the upper opening, and the inflator can be inserted into the diffuser from the lower opening.

[0010] The diffuser may be configured to extend from the side cushion to the head protection cushion.

[0011] The diffuser has an inner diffuser surface facing the occupant side and an outer diffuser surface opposite thereto, and the second opening can be formed in at least one of the inner diffuser surface and the outer diffuser surface.

[0012] The side cushion may have a side cushion inner panel facing the diffuser inner surface and a side cushion outer panel facing the diffuser outer surface, and the second opening of the diffuser may be configured to face at least one of the side cushion inner panel and the side cushion outer panel.

[0013] It is preferable that the head protection cushion be configured to be deployed prior to the side cushion.

[0014] The side cushion may be provided on a vehicle center side with respect to the vehicle seat, and an area ratio of the first opening to the second opening may be in a range of 3:1 to 4:1.

[0015] The downstream end of the diffuser and the inner surface of the head protection cushion can be connected by sewing.

[0016] The head protection cushion may include a first chamber that protects the side of the occupant; a second chamber that is connected to the first chamber and protects the front of the occupant's head; a third chamber that is connected to the second chamber and deploys from the front of the occupant's head to the other side; and a fourth chamber that is connected to the third chamber and deploys on the other side of the occupant.

[0017] In this way, by surrounding the occupant's head on one side, the front, and the other side with the airbag, it is possible to reliably restrain the occupant's head regardless of the seat position, reclining angle, etc. According to the present invention, there is no need to use the steering wheel, instrument panel, etc. as a reaction surface when the airbag deploys, and stable performance can be achieved regardless of the seat position, etc.

[0018] The first chamber may include an upper direction portion that first deploys upward, and a forward direction portion that is connected to the upper direction portion and deploys forward.

[0019] The side cushion is connected to the vicinity of the lower end of the upper portion of the first chamber and can protect the sides of the occupant's body. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a perspective view mainly showing the external shape of a vehicle seat to which an airbag device according to the present invention can be applied, and the airbag device is not shown. [Diagram 2] FIG. 2 is a perspective view showing an internal structure (seat frame) that functions as a framework of the vehicle seat shown in FIG. 1, and an airbag device is omitted from the illustration. [Diagram 3] FIG. 3 is a schematic side view of a vehicle seat equipped with an airbag device according to an embodiment of the present invention, showing the state in which the airbag device is housed as seen through from the outside in the vehicle width direction. [Figure 4] FIG. 4 is a top view that typically shows a state in which the airbag is deployed in the airbag device according to the embodiment of the present invention. [Diagram 5] FIG. 5 is a top perspective view (bird's-eye view) showing a state in which the airbag is deployed in the airbag device according to the embodiment of the present invention. [Figure 6] FIG. 6 is a front perspective view showing a state in which the airbag is deployed in the airbag device according to the embodiment of the present invention. [Figure 7]FIG. 7 is a plan view showing the shape of a panel constituting an airbag used in an airbag device according to an embodiment of the present invention, which defines the first and second chambers. [Figure 8] FIG. 8 is a plan view showing the shape of a panel constituting an airbag used in an airbag device according to an embodiment of the present invention, which panel forms a side chamber. [Figure 9] FIG. 9 is a plan view showing the configuration of a diffuser used in an airbag device according to an embodiment of the present invention, in which (A) shows the diffuser in a folded state, and (B) shows the diffuser in an unfolded state prior to folding. [Figure 10] FIG. 10 is a schematic diagram for explaining a projection plane that serves as a setting reference for the maximum projection area of ​​the first opening of the diffuser. [Figure 11] FIG. 11 is a plan view showing the shape of a panel constituting an airbag used in an airbag device according to an embodiment of the present invention, which panel forms a third chamber. [Figure 12] FIG. 12 is a plan view showing the shape of a panel constituting an airbag used in an airbag device according to an embodiment of the present invention, which panel forms a fourth chamber. [Figure 13] FIG. 13 is a plan view for explaining the connection relationship of the panels shown in FIGS. 7 to 9, 11 and 12. FIG. [Figure 14] FIG. 14 is a plan view showing a state in which the panels shown in FIGS. 7 to 9, 11 and 12 are connected together. [Figure 15] FIG. 15 is a cross-sectional view taken along the line AA in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] The airbag device according to the present invention will be described below with reference to the accompanying drawings. In the following description, when an occupant sits on a seat in a normal position, the direction in which the occupant faces is referred to as "forward", the opposite direction is referred to as "rear", and the coordinate axes are referred to as "front-rear direction". When an occupant sits on a seat in a normal position, the right side of the occupant is referred to as "right direction", the left side of the occupant is referred to as "left direction", and the coordinate axes are referred to as "left-right direction". When an occupant sits on a seat in a normal position, the head direction of the occupant is referred to as "upward", the waist direction of the occupant is referred to as "downward", and the coordinate axes are referred to as "up-down direction". In addition, in the deployed airbag, the side facing the occupant (head) is referred to as the inside, and the opposite side is referred to as the outside.

[0022] Fig. 1 is a perspective view mainly showing the external shape of a vehicle seat used in the passenger protection device according to the present invention, and an airbag device (20) is not shown. Fig. 2 is a perspective view showing an internal structure (seat frame) that functions as a framework of the vehicle seat shown in Fig. 1, and again, an airbag device (20) is not shown. Fig. 3 is a schematic side view of the passenger protection device according to the present invention, showing a state in which the airbag device 20 is housed on the side (far side) of the vehicle seat far from the door, as viewed from the outside in the vehicle width direction.

[0023] A vehicle seat to which the present invention is applicable is, when viewed as a whole, composed of a seat cushion 2 on which an occupant sits, a seat back 1 forming a backrest, and a headrest 3 connected to the upper end of the seat back 1, as shown in Figures 1 and 2.

[0024] A seat back frame 1f is provided inside the seat back 1, forming the framework of the seat, and a pad made of urethane foam or the like is provided on and around the seat back frame 1f, and the surface of the pad is covered with a covering such as leather, fabric, etc. A seat frame 2f is disposed on the bottom side of the seat cushion 2, and a pad made of urethane foam or the like is provided on the top surface and around the seat back frame 2f, and the surface of the pad is covered with a covering such as leather, fabric, etc. The seat frame 2f and the seat back frame 1f are connected via a reclining mechanism 4.

[0025] 2, the seat back frame 1f is configured in a frame shape by seat frames 10 arranged spaced apart on the left and right and extending in the vertical direction, an upper frame connecting the upper ends of the seat frames 10, and a lower frame connecting the lower ends of the seat frames 10. The headrest 3 is configured by providing a cushion member on the outside of the headrest frame.

[0026] FIG. 3 is a schematic side view of a vehicle seat equipped with an airbag device 20 according to an embodiment of the present invention, showing the airbag device 20 housed as seen through from the outside in the vehicle width direction.

[0027] 3, the airbag device 20 is accommodated near the upper right end of the seat back 1 of the vehicle seat. In this embodiment, the airbag device 20 is disposed on the so-called far side, but it is also possible to dispose it on the near side.

[0028] Fig. 4 is a top view showing a schematic diagram of the airbag (30) deployed in the airbag device 20 according to the embodiment of the present invention. Fig. 5 is a top perspective view (bird's-eye view) showing the airbag (30) deployed. Fig. 6 is a front perspective view showing the airbag (30) deployed. In Figs. 4 and 5, the dashed lines indicate sewing lines.

[0029] As shown mainly in Fig. 4, the airbag device 20 according to this embodiment includes: an inflator 160 (see Figs. 6 and 8) that generates inflation gas; and an airbag 30 that protects the head area of ​​an occupant P by deploying from near the upper right end of a vehicle seat. The airbag 30 includes a first chamber 32 that protects one side of the head of the occupant P; a second chamber 34 that is connected to the first chamber 32 and protects the front of the head of the occupant P; a third chamber 36 that is connected to the second chamber 34 and deploys from the front of the head of the occupant P to the other side; and a fourth chamber 38 that is connected to the third chamber 36 and deploys on the other side of the head of the occupant P. The first to fourth chambers 32, 34, 36, 38 form a head protection cushion.

[0030] The airbag device 20 further includes a tether 200 that extends in the deployment direction (forward) of the airbag 30 and regulates the deployed shape of the airbag 30, and a holding member 202 that holds the tether 200 slidably along the surface of the airbag 30. The details of the tether 200 and the holding member 202 will be described later with reference to FIG.

[0031] The tether 200 has a first end 201a connected to the inner surface of the second chamber 34 and a second end 201b opposite to the first end 201a. The second end 201b is connected to the seat frame. The second end 201b (rear end) of the tether 200 can be connected to a structural part other than the seat frame, or can be directly connected to the vicinity of the rear end of the first chamber 32.

[0032] The first chamber 32 and the second chamber 34 are integrally molded as a single chamber. The rear portion of the second chamber 34 is bent in a direction approaching the head of the occupant P, which allows the second chamber 34 to be deployed reliably in front of the occupant's head.

[0033] A tether 200 is connected so as to span the first chamber 32 and the second chamber 34, and when the airbag 30 is deployed, the tension of the tether 200 causes the second chamber 34 to bend.

[0034] As shown in Figs. 4 to 6, the side chamber 40 is connected below the first chamber 32. The side chamber 40 restrains at least the right shoulder area of ​​the occupant P, but may be configured to restrain the occupant P up to the waist area. The side chamber 40 and the first chamber 32 are configured to deploy simultaneously or one of them deploys first depending on the direction and timing of the force applied to the occupant P to be protected. As shown in Figs. 6 and 8, inflation gas is released from the inflator 160 housed in the side chamber 40, and the gas flows in the order of the first chamber and / or side chamber 40, the second chamber 34, the third chamber 36, and the fourth chamber 38. The side chamber 40 corresponds to the "side cushion" described in the claims.

[0035] As shown in Figs. 4 and 5, the four chambers (32, 34, 36, 38) are deployed to surround the occupant P from the vicinity of the right head to the vicinity of the left head. The second chamber 34 is deployed to bend from the first chamber 32 toward the occupant (inward) and, at the same time, bends slightly upward as shown in Fig. 6, so as to reliably protect the front, including the diagonally forward, part of the head (face) of the occupant P. Since the airbag 30 (at least the first chamber 32 and the fourth chamber 38) is located above the shoulder of the occupant P, it is possible to prevent the shoulder of the occupant P from interfering with the deployment behavior and causing it to deteriorate. In addition, since the airbag 30 is placed on the shoulder of the occupant P, the distance between the airbag 30 and the head of the occupant P can be reduced, and the occupant's head can be quickly restrained.

[0036] 4 and 5, in a top view when the airbag 30 is inflated and deployed, the longitudinal direction of the second chamber 34 is angled from the bent region 200a to extend forward of the occupant P with respect to the longitudinal direction of the first chamber 32, which is long in the front-rear direction. The direction of inflation and deployment of the third chamber 36 from the gas inlet of the third chamber 36 near the terminal end of the second chamber 34 to the gas inlet of the fourth chamber 38 is generally opposite in the front-rear direction to the longitudinal direction of the first chamber 32, and is angled with respect to the longitudinal direction of the inflated and deployed second chamber 34 in a direction approaching the occupant P from the terminal end of the second chamber 34. Furthermore, the direction in which the fourth chamber 38 inflates and deploys from the gas inlet of the fourth chamber 38, which is located near the end of the third chamber 36, is generally opposite in the front-rear direction to the longitudinal direction of the first chamber 32, and is angled in a direction approaching the occupant P from the end of the third chamber 36 with respect to the direction of inflation and deployment of the third chamber 36. With this configuration, the airbag 30 inflates and deploys from one of the shoulders of the occupant P so as to wrap around the head of the occupant P.

[0037] Fig. 7 is a plan view showing the panels (foundation fabrics) forming the first chamber 32 and the second chamber 34. As shown in Fig. 7, the first chamber 32 and the second chamber 34 are integrally formed by bonding together two pieces of foundation fabric 130a (inner panel) and 130b (outer panel). In the figure, reference numeral 132 indicates an area corresponding to the first chamber 32, and 134 indicates an area corresponding to the second chamber. When the first chamber 32 and the second chamber 34 are deployed, the inner panel 130a faces the occupant P side.

[0038] The first chamber 32 (region 132) has an opening 154 connected to the side chamber 40 and a tab 152 connected to a tab 164 of the side chamber 40. The opening 154 allows inflation gas to flow into the first chamber 32 from the vicinity of the rear end of the side chamber 40. A vent opening 150a that is in fluid communication with the third chamber 36 is formed so as to extend in a direction along the lower edge of the second chamber near the end of the inner panel of the second chamber 34, and is connected together with a vent opening 150b of the inner panel 136a (see FIG. 9) of the third chamber 36 by sewing around the periphery. The vent openings 150a and 150b form a vent hole 37.

[0039] The first chamber 32 is roughly configured to include an upper direction section 132a that guides the gas flowing in from the opening 154 upward, and a front direction section 132b that is connected to the upper direction section 132a and extends forward. In Fig. 7, the dashed lines other than those of the upper direction section 132a and the front direction section 132b indicate sewing lines.

[0040] In the first chamber 32, the inflation gas first flows into the upper direction portion 132a, so that the first chamber 32 can be quickly and reliably raised to above the shoulders of the occupant P.

[0041] Fig. 8 is a plan view showing the panels (base fabrics) forming the side chamber 40. As shown in Fig. 8, the side chamber 40 is formed by bonding together two base fabrics 140a (inner panel) and 140b (outer panel) of approximately the same shape. In the figure, reference numeral 166 denotes an opening connected to the opening 154a of the first chamber 32, and reference numeral 162 denotes an inflator holding portion that houses the inflator 160. Reference numeral 164 denotes a tab connected to the tab 152 of the first chamber 32.

[0042] The side chamber 40 and the first chamber 32 are directly connected at the respective openings 154a, 166, and the deployment posture can be controlled by connecting the tabs 152, 164 together. In FIG. 8, the dashed lines other than the inflator 160 indicate sewing lines. The connection tab 164 is provided on the upper edge of the side protection cushion 40. The tab 152 of the first chamber 32 is provided on the lower edge of the first chamber, and by connecting these tabs 152, 164 together, unintended swinging during inflation and deployment is reduced, and the stability of the inflation and deployment is increased. In addition, by connecting the tabs 152, 164 together, the airbag cushion does not expand and deploy in different directions during inflation and deployment, and the occupant P can be protected more integrally and comprehensively.

[0043] As shown in FIG. 8, a diffuser 180 that guides gas released from the inflator 160 to the side chamber 40 and the first chamber 32 is inserted and disposed inside the inflator holding portion 162.

[0044] 9 is a plan view showing the configuration of diffuser 180, where (A) shows the diffuser 180 in a folded (completed) state, and (B) shows the diffuser in an unfolded state before folding. Diffuser 180 is provided so as to cover the periphery of the gas discharge portion of inflator 160, and includes a first opening 182 communicating with first chamber 32 and a second opening 187 communicating with a side cushion. In this embodiment, second opening 187 is a circular hole.

[0045] The diffuser 180 has a diffuser inner surface 180a facing the occupant side and a diffuser outer surface 180b on the opposite side, and the second opening 187 is formed in the diffuser outer surface 180b. The second opening 187 may be provided on the inner surface 180a instead of the outer surface 180b of the diffuser 180, and may also be provided on both the inner surface 180a and the outer surface 180b.

[0046] With regard to first opening 182 and second opening 187, the maximum projected area of ​​first opening 182 when each is fully open is set to be larger than that of second opening 187. Since second opening 187 is formed on the side surface of diffuser 180, the maximum projected area of ​​second opening 187 is the area of ​​a circle on the panel (base fabric).

[0047] FIG. 10 is a schematic diagram for explaining a projection plane that is a reference for setting the maximum projection area of ​​the first opening 182 of the diffuser 180. For example, when the first opening is the upper opening of a cylindrical diffuser as shown in FIG. 10(A), the plane A1 perpendicular to the longitudinal axis is the maximum projection area of ​​the projection plane. Also, as shown in FIG. 10(B), when the first opening is cut obliquely at the upper part of the cylindrical diffuser, the plane A3 parallel to the inclination angle of the opening, not the plane A2 perpendicular to the longitudinal axis, is the projection plane that is the reference for the maximum projection area. In other words, when the opening is viewed from a position away from the opening, the projection plane when viewed from a position where the projection area of ​​the projection plane on which the entire surrounding opening is projected is maximized is called the projection plane with the maximum projection area of ​​the opening. The position from which the opening is viewed is a position vertically away from the center of the projection plane with the maximum projection area (the center of the figure of the projection plane).

[0048] In this embodiment, the area ratio of the first opening 182 to the second opening 187 is preferably 3:1 to 4:1. In this case, when a plurality of second openings 187 are provided, the opening area of ​​the second opening is the sum of the opening areas of all the second openings 187. If the first opening is relatively smaller than this ratio (less than 3), there is a risk that the flow rate of gas per unit time cannot be secured to fill the head protection cushion with gas within a predetermined time. Since the side chamber is usually disposed on the far side of the vehicle seat, it may be deployed later than the head protection cushion. However, if the first opening is relatively larger than this ratio (greater than 4), the gas flow from the second opening to the side cushion is narrowed, so the deployment time is delayed and there is a risk that the deployment is not completed by the required time.

[0049] The diffuser 180 is molded in a cylindrical shape having an upper opening (first opening) 182 and a lower opening 181, and the inflator 160 is inserted into the diffuser 180 from the lower opening 181 and fixed therein.

[0050] As shown in FIGS. 8 and 14, the diffuser 180 extends from the side chamber 40 to the inside of the first chamber 32, with the first opening 182 located within the first chamber 32.

[0051] As shown in Fig. 9(A), diffuser 180 has tabs 183, 184 on both the front and rear sides of the upper end thereof, which are connected to first chamber 32. As also shown in Fig. 13, these tabs 183, 184 are sewn together with inner panel 130a and outer panel 130b constituting first chamber 32 along sewing lines 183a, 184a, and two points of the upper end portion of diffuser 180 are fixed.

[0052] As shown in FIG. 9(B), the panels constituting diffuser 180 are formed symmetrically, folded along the center line, and inner surface 180a and outer surface 180b are connected to each other by sewing lines 185, 186 to form a cylindrical shape.

[0053] Fig. 11 is a plan view showing a panel (base fabric) that forms the third chamber 36. In Fig. 11, the dashed lines indicate sewing lines.

[0054] As shown in FIG. 11, the third chamber 36 is formed by bonding two base fabrics 136a (inner panel) and 136b (outer panel). A vent opening 150b connected to the vent opening 150a of the second chamber 34 is formed near one end of the inner panel 136a. A vent opening 170a connected to the vent opening 170b of the fourth chamber 38 is formed near the other end of the inner panel 136a. The vent openings 170a and 170b form a vent hole 39 (FIGS. 7 and 11). The vent hole opening 150b is longer in the short side direction than the vent opening 170a, and has a larger opening area.

[0055] Fig. 12 is a plan view showing the panel (base fabric) 138 that forms the fourth chamber 38. In Fig. 12, the dashed lines indicate sewing lines.

[0056] 12, the fourth chamber 38 is formed into a bag shape by folding one panel 138 in half. A vent hole 170b that connects to the vent hole 170a of the third chamber is formed near the center of the panel 138 in the longitudinal direction, and the center line of the vent opening 170b along the longitudinal direction becomes the fold line of the panel 138.

[0057] Fig. 13 is a plan view for explaining the connection of the panels shown in Figs. 7 to 9, 11, and 12. Fig. 14 is a plan view showing the state in which these panels are connected. Fig. 15 is a cross-sectional view in the AA direction of Fig. 14.

[0058] 12, the chamber formed by integrating the first chamber 32 and the second chamber 34 has the largest capacity, followed by the side chamber 40. In contrast, the third chamber 36 has a small capacity, and the fourth chamber 38 has an even smaller capacity.

[0059] The second chamber 34 and the third chamber 36 are connected by sewing only around the periphery of the vent openings 150a and 150b, and the third chamber 36 and the fourth chamber 38 are connected by sewing only around the periphery of the vent openings 170a and 170b.

[0060] The diffuser 180 is disposed so as to be sandwiched between the inner surface 180a and the outer surface 180b of the side chamber 40, and is connected to the first chamber 32 by the tabs 183, 184, as described above. The lower end (second opening 181) of the diffuser 180, the lower end of the inflator holding portion 162 of the side chamber 40, and the inflator 160 are sealed from the outside of the side chamber 40 by a means such as wrapping tape around them.

[0061] (Airbag compression) From the state shown in FIG. 14, the tether 200 is pulled backward (pulled in) to form a shrunk region around the tether 200 in the first chamber 32 and the second chamber 34, and the upper and lower portions of the shrunk region are compressed by folding them accordion-like toward the center.

[0062] The third and fourth chambers 36, 38 are then accordion folded together and rolled. Finally, the side chambers 40 are accordion folded or rolled to complete the compression process of the airbag 30.

[0063] (Airbag deployment behavior) As shown in Figures 4 to 6, in the airbag device 20 of this embodiment, when a vehicle collision event occurs, the inflator 160 is activated and the inflation gas flows from the first opening 182 of the diffuser 180 into the first chamber 32 and from the second opening 187 into the side chamber 40.

[0064] 15, the second opening 187 formed on the inner surface of the diffuser 180 faces closely to the outer panel 140b of the side chamber 40, and cannot be opened widely immediately after the inflator 160 is activated, so that most of the inflation gas inside the diffuser 180 is sent into the first chamber 32 through the first opening 182. After that, a gap is generated between the outer panel 140b of the side chamber 40 and the second opening 187, and the amount of gas flowing into the side chamber 40 through the second opening 187 increases.

[0065] In this embodiment, the first opening 182 of the diffuser 180 has a larger area than the second opening 187, and the second opening 187 faces the panel of the side chamber 40, so that the first chamber 32, the second chamber 34, the third chamber 36, and the fourth chamber 38 deploy quickly before the side chamber 40 deploys.

[0066] When inflation gas flows into the first chamber 32, the upper direction section 132a (FIG. 7) inflates first, followed by the front direction section 132b. Gas then flows from the first chamber 32 into the second chamber .

[0067] At this time, since the first chamber 32 and the second chamber 34 or the second chamber 34 and the seat frame are connected by the tether 200 (FIG. 4), the second chamber 34 is restricted from deploying forward and bends from the bent portion 200a of the tether 200, i.e., the bent region 202a of the retaining member 202, as a starting point, and deploys toward the front of the occupant (FIGS. 4 and 5). Note that the second chamber 34 bends so that the tip side faces upward as shown in FIG. 6, and deploys so that the vent opening 150a is generally vertically long.

[0068] Next, the inflation gas flows from the second chamber 34 to the third chamber 36 through the vent hole 37, and the third chamber 36 deploys in front of the occupant P near the left head. Because the inner panel 134a of the second chamber 34 and the inner panel 136a of the third chamber 36 are connected to each other around the vent hole 37, the behavior of the third chamber 36 deploying to spread outward (away from the occupant's head) is restricted, and a curved shape is created to surround the head of the occupant P.

[0069] Next, the inflation gas flows from the third chamber 36 to the fourth chamber 38 through the vent hole 39, and the fourth chamber 38 deploys near the left head of the occupant P. Because the inner panel 136a of the third chamber 36 and the fourth chamber 36 are connected around the vent hole 39, the behavior of the fourth chamber 36 deploying to spread outward (away from the occupant's head) is restricted, and a curved shape is created to surround the head of the occupant P. With these structures, the airbag 30 deploys to inflate and wrap around the head of the occupant P.

[0070] In this embodiment, the tether 200 is slid along the surface of the airbag 30, so that the tether 200 does not protrude in a bridge shape from the surface of the airbag 30, and unnecessary interference with the occupant P can be avoided. In addition, the deployed shape of the airbag 30 can be reliably and precisely controlled.

[0071] Although the present invention has been described in connection with the above exemplary embodiments, many equivalent modifications and variations will be apparent to those skilled in the art from this disclosure. Therefore, the above exemplary embodiments of the present invention are considered to be illustrative and not limiting. Various changes may be made to the described embodiments without departing from the spirit and scope of the present invention. For example, in the description of the embodiment, the far side airbag is mainly described in the examples, but the present invention can also be used in near side airbags (the surface of the vehicle seat far from the vehicle door) and single-seat vehicles (vehicles including a portion with only one seat in a row regardless of whether there is a door) in ultra-compact vehicles such as small mobility vehicles.

Claims

1. An airbag device accommodated in a vehicle seat, an inflator that generates inflation gas; an airbag that protects an occupant by deploying from a side portion of the vehicle seat; The airbag includes a head protection cushion that is deployed at least on the sides of the head of the occupant, and a side cushion that is deployed on the sides of the occupant's shoulders to waist, The inflator includes a gas discharge portion, and is provided so that at least the gas discharge portion is accommodated inside the side cushion. a diffuser is provided inside the airbag so as to cover the periphery of the gas discharge portion of the inflator; The diffuser includes a first opening communicating with the head protection cushion and a second opening communicating with the side cushion, a maximum projected area of ​​the first opening and a maximum projected area of ​​the second opening when the first opening and the second opening are fully opened are set to be larger than a maximum projected area of ​​the second opening, The diffuser has an inner diffuser surface facing an occupant side and an outer diffuser surface opposite thereto, The airbag device according to claim 1, wherein the second opening is formed in at least one of an inner surface and an outer surface of the diffuser.

2. The diffuser is formed in a cylindrical shape having an upper opening and a lower opening, 2. The airbag device according to claim 1, wherein the first opening corresponds to the upper opening, and the inflator is inserted into the diffuser through the lower opening.

3. 3. The airbag device according to claim 1, wherein the diffuser extends from the side cushion to the head protection cushion.

4. The side cushion has a side cushion inner panel facing the diffuser inner surface and a side cushion outer panel facing the diffuser outer surface, 2. The airbag device of claim 1, wherein the second opening of the diffuser faces at least one of the side cushion inner panel and the side cushion outer panel.

5. An airbag device as described in claim 1 or 2, characterized in that the head protection cushion deploys prior to the side cushion.

6. The side cushion is provided on the vehicle center side with respect to the vehicle seat, 3. The airbag device according to claim 1, wherein an area ratio of the first opening to the second opening is in the range of 3:1 to 4:

1.

7. An airbag device as described in claim 1 or 2, characterized in that the downstream end of the diffuser and the inner surface of the head protection cushion are connected by sewing.

8. An airbag device accommodated in a vehicle seat, an inflator that generates inflation gas; an airbag that protects an occupant by deploying from a side portion of the vehicle seat; The airbag includes a head protection cushion that is deployed at least on the sides of the head of the occupant, and a side cushion that is deployed on the sides of the occupant's shoulders to waist, The inflator includes a gas discharge portion, and is provided so that at least the gas discharge portion is accommodated inside the side cushion. a diffuser is provided inside the airbag so as to cover the periphery of the gas discharge portion of the inflator; The diffuser includes a first opening communicating with the head protection cushion and a second opening communicating with the side cushion, a maximum projected area of ​​the first opening and a maximum projected area of ​​the second opening when the first opening and the second opening are fully opened are set to be larger than a maximum projected area of ​​the second opening, an airbag device, characterized in that the head protection cushion comprises: a first chamber that protects the side of the occupant; a second chamber that is connected to the first chamber and protects the front of the occupant's head; a third chamber that is connected to the second chamber and deploys from the front of the occupant's head to the other side; and a fourth chamber that is connected to the third chamber and deploys at the other side of the occupant.

9. The diffuser is formed into a cylindrical shape having an upper opening and a lower opening, 9. The airbag device according to claim 8, wherein the first opening corresponds to the upper opening, and the inflator is inserted into the diffuser through the lower opening.

10. 10. The airbag device according to claim 8, wherein the first chamber includes an upper direction portion that first deploys upward, and a front direction portion that is connected to the upper direction portion and deploys forward.

11. 11. The airbag device according to claim 10, wherein the side cushion is connected to a lower end of the upper portion of the first chamber to protect the side of the occupant's body.

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