JP2007308088A - Airbag device for front passenger seat - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an airbag device for a front passenger seat capable of suppressing upward movement at a rear part side of the airbag at completion of inflation and restriction of an occupant by suppressing increase of capacity of the airbag. <P>SOLUTION: In the airbag device M1 for the front passenger seat, a case 12 arranged on an instrument panel 1 at a front side of the front passenger seat and storing the airbag 24 is provided with a bottom wall part 12a mounted with the airbag 24 and a peripheral wall part 12b. The airbag 24 is constituted by a vehicle body side wall part 26 in which a portion at a front end side at completion of inflation is mounted to a bottom wall part 14; an outer side wall part 31 for bonding both left and right edges to the vehicle body side wall part above the vehicle body side wall part; and a front wall part 34. The vehicle body side wall part 26 is provided with an abutment part 29 abutted on an upper surface side of the instrument panel at a front side than the case at completion of inflation. In the front wall part 34, an upper edge 34a side is arranged near an upper part of an axis C of the peripheral wall part 12b of the case 12 viewed from a side at completion of inflation and a lower edge 34b side is made approached to the upper surface 1a side of the instrument panel and is arranged at a front side than the upper edge 34a side. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is an airbag that is folded and housed in a case disposed in an instrument panel in front of a passenger seat, and that protrudes from the case and expands and inflates from the upper surface side of the instrument panel to the passenger seat side when inflating gas flows. It is related with the airbag apparatus for passenger seats comprised by providing.

Conventionally, in this type of airbag device for a passenger seat, as a type constituting the peripheral wall of the airbag, a type constituted by two cloth materials that can be manufactured by plane sewing (for example, see Patent Document 1), or three There is a type which consists of a piece of cloth material (for example, refer to patent documents 2).
JP 2001-163142 A JP-A-9-99793

  However, in the conventional airbag device for the passenger seat, the airbag that has been deployed and inflated is disposed so as not to move upward on the rear side, including when the passenger seated on the passenger seat is received on the rear side. Is configured to abut and support the front side on the windshield above the instrument panel.

  And, in the case of configuring the airbag that has been inflated to hit the windshield, the capacity of the airbag is increased, and an inflator with a large output that increases the discharge amount of the inflation gas is required. As a result, the weight and cost of the airbag apparatus are increased.

  The present invention solves the above-described problems, and provides an airbag device for a passenger seat that can suppress an increase in the capacity of the airbag and suppress an upward movement of the rear side of the airbag at the time of completion of inflation or restraining an occupant. The purpose is to do.

An airbag device for a passenger seat according to the present invention is folded and housed in a case disposed in an instrument panel in front of the passenger seat, and protrudes from the case when an inflating gas flows in, so that a passenger can be seen from the upper surface side of the instrument panel. With an airbag that expands and inflates over the seat side,
An airbag device for a passenger seat, in which the case is configured to include a bottom wall portion serving as an attachment site for attaching the airbag, and a peripheral wall portion extending in a cylindrical shape from the periphery of the bottom wall portion,
A portion of the airbag from the vicinity of the bottom wall portion to the front end side of the airbag when the inflation is completed is disposed on the upper surface side so as to face the vehicle body side wall portion, the vehicle body side wall portion, and the left and right edges. An outer wall portion to be coupled to both left and right edges of the vehicle body side wall portion, and a front wall portion for constituting the front end surface of the airbag and coupling the outer peripheral edge to the front edge of the vehicle body side wall portion and the outer wall portion together. Consists of three flexible cloth materials,
The vehicle body side wall portion includes a contact portion that comes off from the case and contacts the upper surface side of the instrument panel on the front side of the case when the airbag is completely inflated.
When the front wall is completely inflated, the upper edge side of the longitudinal section along the front-rear direction is arranged near the upper part of the axial center of the peripheral wall portion of the case, and the lower edge side of the longitudinal section along the front-rear direction is It is configured to be close to the upper surface side of the instrument panel and to be arranged on the front side with respect to the axis of the peripheral wall portion of the case as compared to the upper edge side.

  In the airbag device for a passenger seat according to the present invention, when the airbag completes the expansion and inflation, the front wall portion, the vehicle body side wall portion, and the outer wall portion constituting the peripheral wall of the airbag are formed on the front end side of the airbag. However, it is swelled by producing a tension, and exhibits a certain degree of shape retention. At this time, the front wall portion is an upper side along the axis of the case peripheral wall portion of the abutting portion that abuts on the upper surface side of the instrument panel in the vehicle body side wall portion, and the upper edge side of the longitudinal section along the front-rear direction. The lower edge side is made to approach the upper surface side of the instrument panel, and the upper side of the case wall is positioned forward from the upper edge side. Therefore, the inflation portion of the airbag on the upper surface side of the instrument panel on the front side of the axial center of the peripheral wall portion of the case forms the bottom wall from the contact portion of the vehicle body side wall portion, and the upper peripheral wall is the front wall. It is comprised from a part, becomes a substantially triangular pyramid shape of the shape which arrange | positioned the upper part near the upper part of the axial center of the surrounding wall part of a case, and extended the lower edge side to the front side.

  Then, when the airbag at the time of completion of inflation moves upward on the rear side, a rotational moment is generated that pushes down the front end side of the airbag with the attachment portion of the airbag attached to the case as the center of rotation. The substantially triangular pyramid-shaped expansion portion makes the contact portion contact the upper surface side of the instrument panel in front of the case and suppresses the rotation thereof. Furthermore, the substantially triangular pyramid-shaped inflated portion that suppresses the upward movement of the rear side of the airbag has a substantially entire peripheral wall on the front side composed of a single front wall, and this front wall is Swelling to generate a large tension up to the binding site on the outer peripheral edge, and then bulging into a curved plate shape with rigidity to suppress wrinkles and deformation that narrows the vertical dimension For this reason, it is possible to reliably regulate the rotation for moving the rear side of the airbag upward.

  That is, since the front side of the airbag at the time of completion of inflation does not extend forward and come into contact with the windshield, the upward movement of the rear side of the airbag can be restricted, so that an increase in the capacity of the airbag can be prevented.

  Therefore, in the passenger seat airbag device according to the present invention, it is possible to suppress an increase in the capacity of the airbag and to suppress upward movement of the rear side of the airbag when the inflation is completed or when the passenger is restrained.

And as an airbag, the rear-wall part which comprises the rear-end surface of an airbag on the rear-end side at the time of completion of inflation, and combines an outer periphery with the rear edge of a vehicle body side wall part and an outside wall part together Provided and configured,
The peripheral wall of the airbag is composed of four flexible cloth materials, a vehicle body side wall, an outer wall, a front wall, and a rear wall.
The vehicle body side wall portion and the outer wall portion are formed in a shape that can be coupled by sewing the left and right edges to each other on a plane,
It is desirable to form the front wall portion and the rear wall portion in shapes that allow the outer peripheral edges to be joined together by plane sewing with respect to the vehicle body side wall portion and the outer wall portion.

  In such a configuration, since the peripheral wall of the airbag can be formed by plane sewing the four vehicle body side wall portions, the outer wall portion, the front wall portion, and the rear wall portion, automatic sewing becomes possible. The manufacture of the airbag is facilitated. In addition, when cutting from a large cloth material for an air bag, as four body side walls, an outer wall, a front wall, and a rear wall that are divided into a relatively small shape by dividing the peripheral wall of the airbag into four parts Since it can cut | judge, it is easy to arrange | position each wall part without a space | gap, generation | occurrence | production of the remaining material from the cloth material for airbags can be decreased, and the yield of the cloth material for airbags can be made favorable.

  Furthermore, the front wall portion when the expansion is completed should be arranged so that the connecting portion with the front edge of the vehicle body side wall portion at the outer peripheral edge viewed from the side is longer than the connecting portion with the front edge of the outer wall portion. Is desirable.

  In such a configuration, when the lower edge side disposed along the upper surface side of the instrument panel at the outer peripheral edge of the front wall portion is longer than the upper edge side, and the ratio of the length of the lower edge side to the upper edge side is small Compared to the above, the substantially triangular pyramid-shaped inflated portion for suppressing the upward movement of the rear side of the airbag at the completion of the inflation has a shape that increases the area on the bottom wall side. As a result, the substantially triangular pyramid-shaped inflatable portion can disperse the rotational moment that moves the rear side of the airbag upward when the inflation is completed over a wide area, and the rotational moment that moves the rear side of the airbag upwards. Even if it is large, the upward movement of the rear side of the airbag can be suppressed stably.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, an airbag device M1 for a passenger seat according to the first embodiment is an instrument panel (hereinafter referred to as an instrument panel) in front of the passenger seat. And a top mount type mounted on the upper surface 1a side of 1. The airbag device M1 for the passenger seat includes a folded airbag 24, an inflator 8 that supplies the inflation gas G to the airbag 24, a case 12 that stores and holds the airbag 24 and the inflator 8, and an airbag 24. Is provided with a retainer 10 for attaching to the case 12 and an airbag cover 17 that covers the folded airbag 24.

  Note that the front-rear, up-down, left-right directions of the embodiment coincide with the front-rear, up-down, left-right directions when the vehicle travels straight when mounted on the vehicle.

  Further, in the case of the embodiment, the instrument panel 1 in which the passenger seat airbag device M1 is mounted has an upper surface 1a inclined forward and downward from a normal instrument panel.

  In the embodiment, the airbag cover 17 is formed integrally with the instrument panel 1 made of synthetic resin. The airbag cover 17 is configured by disposing two front and rear door portions 18F and 18B in which a thin portion to be broken 20 is disposed. The planned fracture portion 20 is arranged in an H shape when viewed from above the instrument panel 1 so that the two door portions 18F and 18B open to the front and rear sides with the front end side and the rear end side as hinge portions 19, respectively. It is configured. Then, when the front and rear door portions 18F and 18B are pushed by the inflating airbag 24 to break the planned breaking portion 20 and open to both the front and rear sides, the airbag 24 is seated on the passenger seat at the top of the case 12. Thus, a substantially rectangular projecting opening 22 that can project to the passenger P side is formed (see FIGS. 12 and 14).

  Further, as shown in FIG. 2, the airbag cover 17 has a connecting wall portion 21 having a substantially rectangular tube shape that protrudes downward from the back surface side so as to surround the arrangement positions of the front and rear door portions 18F and 18B. It is arranged. A plurality of locking holes 21a are penetrated through the connecting wall portion 21 at predetermined positions in portions facing each other in the front-rear direction. Locking claws 15a formed on the case body 13 are inserted into the locking holes 21a, and the connecting wall portion 21 is locked to the locking claws 15a. Locking of the connecting wall portion 21 of each locking claw 15a ensures the connected state of the connecting wall portion 21 and the case body 13, and the airbag 24 when inflated smoothly pushes up the two door portions 18F and 18B. This is so that the planned fracture portion 20 can be broken.

  In the case of the embodiment, the case 12 includes a case main body 13 and a connecting wall portion 21 having a substantially rectangular tube shape of the airbag cover 17. The case main body 13 is made of a sheet metal having a rectangular opening on the upper end side. A rectangular plate-shaped mounting wall portion 14 that is formed in a substantially rectangular parallelepiped shape and forms the bottom wall portion 12a of the case 12, and a side wall that extends upward from the outer peripheral edge of the mounting wall portion 14 to the airbag cover 17 side in a substantially rectangular tube shape. Part 15. And case 12 is comprised from the bottom wall part 12a comprised from the attachment wall part 14, and the substantially square cylinder-shaped surrounding wall part 12b extended upwards from the outer periphery of the bottom wall part 12a. The part 12 b is composed of a side wall part 15 of the case body 13 and a connecting wall part 21 of the airbag cover 17.

  The mounting wall portion 14 of the case body 13 has a rectangular plate shape that extends long in the left-right direction, and is inserted in the center so that the upper side of the inflator 8 is opened in a substantially circular shape that can be inserted from below into the airbag cover 17 side. A hole 14a is provided. An attachment hole 14b through which each bolt 10a of the retainer 10 can be inserted is formed at the periphery of the insertion hole 14a of the attachment wall portion 14. The retainer 10 attaches the airbag 24 and the inflator 8 to the attachment wall portion 14, and the attachment wall portion 14 serves as an attachment portion between the airbag 24 and the inflator 8. The mounting wall 14 is provided with a bracket (not shown) for connecting the case main body 13 to the vehicle.

  The side wall 15 of the case body 13 is formed with a plurality of locking claws 15a that are reversed outward and downward from the case body 13 at the upper ends of the front and rear parts of the vehicle. As described above, each locking claw 15 a is inserted into the locking hole 21 a of the connecting wall portion 21 of the airbag cover 17 to lock the connecting wall portion 21.

  And the peripheral wall part 12b of the case 12 of embodiment is an upper part of the axial center C so that the airbag 24 at the time of expansion | swelling may be easy to go to the back side which becomes a passenger | crew side from the opening 22 for protrusion of the instrument panel 1 in the vehicle mounting state. The side is slightly inclined to the rear side so as to face the rear side from the vertical direction (see FIG. 1). The axis C of the peripheral wall portion 12b of the case 12 coincides with the protruding direction of the airbag 24 from the case 12 at the initial stage of inflation.

  The inflator 8 has a substantially cylindrical shape with a flange portion 8b protruding from the outer periphery, and is configured by disposing a plurality of gas discharge ports 8a capable of discharging the expansion gas G above the flange portion 8b. The flange portion 8b has a substantially quadrangular ring shape (substantially square plate shape), and the mounting holes 8c through which the bolts 10a of the retainer 10 are inserted are passed through the four corners. Each mounting hole 8c is disposed at a position corresponding to each mounting hole 14b of the mounting wall portion 14 of the case body 13, and has the same inner diameter as the inner diameter of the mounting hole 14b.

  The retainer 10 is formed as a quadrangular ring in which the inflator 8 can be inserted from below, and bolts 10a extending downward are projected from the four corners.

  As shown in FIGS. 1 and 3 to 6, the airbag 24 is configured as a substantially quadrangular prism shape extending in the front-rear direction as a shape when the inflation is completed. The peripheral wall 25 of the airbag 24 is formed of four flexible cloth materials, a vehicle body side wall portion 26, an outer wall portion 31, a front wall portion 34, and a rear wall portion 36. These fabric materials are formed from woven fabrics, such as polyester and polyamide.

  The vehicle body side wall portion 26 is disposed on the lower surface side of the airbag 24 when the inflation is completed, and an inflow opening 27 that is opened in a circular shape for allowing the inflation gas to flow in is disposed on the front side. An attachment hole 28 through which each bolt 10 a of the retainer 10 is inserted is formed at the periphery of the inflow opening 27. As shown in FIGS. 7 to 9, the shape in which the vehicle body side wall portion 26 is flattened is tapered at the front and rear ends of a rectangular plate-like portion in which the left and right edges 28 c and 28 d are linear parallel to each other. It is set as the shape which provided the site | part of substantially triangular plate shape (substantially semicircle shape). In addition, two reinforcing cloths 40 and 41 each having a circular shape and a rectangular shape are stitched around the periphery of the inflow opening 27.

  Further, when the airbag 24 is mounted on the vehicle body, the front side portion of the vehicle body side wall portion 26 separates from the case 12 and contacts the portion 4 on the upper surface 1a side (upper surface side portion) 4 of the instrument panel 1. It is set so as to constitute an abutting portion 29 to be in contact with and supported (see FIGS. 12 and 13). In the case of the embodiment, the upper surface side portion 4 is composed of a rear surface 18a of the opened front door portion 18F and a peripheral edge 2 on the front side of the projection opening 22 on the upper surface 1a of the instrument panel 1, as shown in FIG. ing.

  The outer side wall portion 31 is disposed on the upper surface side of the airbag 24 when the inflation is completed, and a vent hole 32 opened in a circular shape is disposed on the rear side of the left and right edges 31c and 31d. As shown in FIGS. 7 to 9, the shape of the outer wall portion 31 that is flattened is tapered at the front and rear ends of a rectangular plate portion in which the left and right edges 31 c and 31 d are linearly parallel to each other. It is set as the shape which provided the site | part of substantially triangular plate shape (substantially semicircle shape).

  The vehicle body side wall portion 26 and the outer side wall portion 31 are connected to the left edge 26c, 31c and the right edge 26d so that the side wall portion 26 and the outer side wall portion 31 can be plane-sewn in a state where the vehicle body side wall portion 26 and the outer wall portion 31 are unfolded flat. 31d has the same outer shape.

  The front wall portion 34 constitutes the front end surface of the airbag 24 when the inflation is completed. The front wall portion 34 is formed so that the outer peripheral edge is coupled to the front edges 26 a and 31 a of the vehicle body side wall portion 26 and the outer wall portion 31 together. In particular, in the case of the embodiment, the front wall portion 34 is formed as a substantially elliptical plate shape extending in the left-right direction, and the outer peripheral edge is an outer side where the outer shape of the upper edge 34a is flattened. Matching the outer shape of the front edge 31a of the wall 31 with the outer shape of the front edge 26a of the vehicle body side wall 26 in which the outer shape of the lower edge 34b is flatly developed, It is comprised so that it can expand | deploy flatly with respect to the front edges 26a and 31a with 31, and can sew on a plane.

  Furthermore, in the case of the embodiment, the front wall portion 34 is, as shown in FIG. 12C and FIG. 13, shown in FIG. 12C and FIG. The center 34ac in the left-right direction of the edge 34a (the upper edge center or the upper edge upper end) 34ac is disposed near the upper portion of the axis C of the peripheral wall portion 12b of the case 12, and the lower edge 34b side, that is, the left and right sides of the lower edge 34b The direction center (lower edge center or lower edge rear end) 34bc is brought closer to the upper surface 1a side of the instrument panel 1, and compared with the upper edge center 34ac, the axis C of the peripheral wall portion 12b of the case 12 is used as a reference. It is configured to be arranged on the front side. In other words, the front edge 26a of the vehicle body side wall portion 26 is located at the position where the front edges 26a and 31a of the vehicle body side wall portion 26 and the outer wall portion 31 are located, with reference to the axis C of the peripheral wall portion 12b of the case 12. The vehicle body side wall part 26 and the outer side wall part 31 are formed so as to be shifted from the front edge 31a of the outer side wall part 31 to the front side.

  Furthermore, in the case of the embodiment, when the airbag 24 is completely inflated in the vehicle mounted state, the front wall portion 34 is disposed symmetrically with respect to the axis C of the peripheral wall portion 12b of the case 12. , A joint portion (a portion from the boundary portion 34d between the upper edge 34a and the lower edge 34b to the lower edge center 34bc) 34bh on the outer peripheral edge 31a of the vehicle body side wall portion 26 on the outer peripheral edge as viewed from the side surface. It is disposed so as to be longer than the coupling portion with the front edge 31a (the portion from the boundary portion 34d between the upper edge 34a and the lower edge 34b to the upper edge center 34ac) 34ah. That is, the front wall portion 34 has a length along the outer peripheral edge extending in the left-right direction, and the lower edge 34b is longer than the upper edge 34a. In other words, the lower edge 34b is curved from the upper edge 34a. Are configured to protrude. In the case of the embodiment, when the airbag 24 at the time of completion of inflation is viewed from the side, the boundary portion 34d between the upper edge 34a and the lower edge 34b is located behind the axial center C of the peripheral wall portion 12b of the case 12. positioned.

  The rear wall portion 36 constitutes the rear end surface of the airbag 24 when the inflation is completed. The rear wall portion 36 is formed so that the outer peripheral edge is coupled to the rear edges 26b and 31b of the vehicle body side wall portion 26 and the outer wall portion 31 together. Further, the rear wall portion 36 is formed as a substantially elliptical plate shape extending in the left-right direction with the flat developed shape, and the outer peripheral edge thereof is the rear edge 31b of the outer wall portion 31 in which the outer shape of the upper edge 36a is developed flat. The outer edge shape of the lower side edge 36b is matched with the outer shape of the rear edge 26b of the vehicle body side wall portion 26 in which the lower edge 36b is flattened. It is comprised so that it can expand | deploy flat with respect to 31b, and can sew on a plane.

  The airbag 24 at the time of completion of the inflation is configured such that the occupant restraint surface 38 that receives the occupant P is a region extending from the rear wall portion 36 on the rear surface side of the airbag 24 to the vicinity of the rear portion 31e of the outer wall portion 31 ( (See C in FIG. 12).

  The manufacture of the airbag 24 of the first embodiment will be described. As shown in FIG. 8, the vehicle body side wall part 26, the outer side wall part 31, the front wall part 34, the rear wall part 36, and the reinforcing cloths 40 and 41 are punched out from the airbag cloth material 45 before cutting. Prepare.

  First, as shown in FIGS. 9A and 9B, the reinforcing cloths 40 and 41 are stitched to the vehicle body side wall portion 26, and the inflow opening 27 and the attachment hole 28 are punched and formed. Next, as shown in FIG. 9B and FIG. 10A, the vehicle body side wall portion 26 and the outer side wall portion 31 are overlapped with each other on the outer peripheral surface side of the airbag 24 so as to be flattened. The left edges 26c, 31c and the right edges 26d, 31d are sewn by plane sewing. After that, as shown in FIGS. 10A and 10B, the front edge 26a of the vehicle body side wall portion 26 is bent so that the front edge 26a side is opened, and the front edges 26a and 31a of the vehicle body side wall portion 26 and the outer wall portion 31 are flatly developed. In addition, the front wall portion 34 that is flatly developed is overlapped on the part, the lower edge 34b of the front wall portion 34 and the front edge 26a of the vehicle body side wall portion 26, and the upper edge 34a of the front wall portion 34 and the outer wall portion. The front edges 31a of 31 are sewn by plane sewing. Further, as shown in FIG. 10B and FIG. 11A, the rear edge 26b of the vehicle body side wall portion 26 and the outer side wall portion 31 are flattened by folding the vehicle body side wall portion 26 so that the rear edge 26b side is opened. And the rear wall portion 36 that is flatly spread on the portion is overlapped, and the lower edge 36b of the rear wall portion 36 and the rear edge 26b of the vehicle body side wall portion 26 and the upper edge 36a of the rear wall portion 36 The rear edges 31b of the outer side wall portion 31 are sewn by plane sewing. And as shown to A and B of FIG. 11, if the airbag 24 is turned over using the inflow opening 27 so that the seam allowance at the time of stitching may not appear on the outer peripheral surface side, the airbag 24 is manufactured. be able to. Note that the front wall 34 and the rear wall 36 of the vehicle body side wall 26 and the outer wall 31 may be stitched to the rear wall 36 first, and then the front wall 34 may be stitched.

  The mounting of the airbag 24 manufactured as described above on a vehicle will be described. First, the airbag 24 is folded with the retainer 10 disposed therein so that the bolts 10a protrude from the mounting holes 28. Further, the folded airbag 24 is wrapped with a wrapping material 47 (see FIG. 2) that can be broken so as not to collapse.

  Then, the folded airbag 24 is placed on the mounting wall portion 14 in the case body 13 while the bolts 10a are inserted through the mounting holes 14b from above. Next, the upper side of the inflator 8 is inserted into the insertion hole 14a and the inflow opening 27 from below, and each bolt 10a protruding downward from the mounting wall portion 14 is inserted into the mounting hole 8c of the flange portion 8b of the inflator 8. Let Then, if the nut 11 is fastened to each bolt 10a protruding from the flange portion 8b of the inflator 8, the folded airbag 24 and the inflator 8 can be attached to the mounting wall portion 14 of the case body 13.

  Thereafter, the side wall 15 of the case main body 13 is inserted into the connecting wall 21 of the airbag cover 17 in the instrument panel 1 mounted on the vehicle, and the locking claws 15 a of the case main body 13 are locked to the connecting wall 21. It is inserted into the hole 21 a and locked to the connecting wall portion 21. Further, if a bracket (not shown) of the case body 13 is fastened to a member on the vehicle body side, the passenger seat airbag device M1 can be mounted on the vehicle.

  After the passenger seat airbag device M1 is mounted on the vehicle, if the passenger seat airbag device M1 operates and the inflation gas G is discharged from each gas discharge port 8a of the inflator 8, the airbag 24 is expanded. Then, the wrapping material 47 is broken, and the scheduled breakage portion 20 of the airbag cover 17 is broken to open the two door portions 18F and 18B forward and backward as shown in FIGS. As shown in FIGS. 12A to 12C, the air bag cover 17 protrudes greatly from the open opening 22 of the two door portions 18F and 18B in the airbag cover 17, and the inflation is completed.

  In the passenger seat airbag apparatus M according to the first embodiment, as shown in FIG. 12C, FIG. 13, and FIG. 14, when the airbag 24 completes the expansion and inflation, the front end 24a side of the airbag 24 is located. Then, the front wall part 34, the vehicle body side wall part 26, and the outer side wall part 31 that constitute the peripheral wall 25 of the airbag 24 are inflated by generating tension and exhibiting a certain degree of shape retention. . At this time, the front wall portion 34 is on the upper side along the axis C of the peripheral wall portion 12b of the case 12 in the contact portion 29 that contacts the upper surface side portion 4 of the instrument panel 1 in the vehicle body side wall portion 26, and the center of the upper edge (Upper edge upper end) 34ac is disposed in the vicinity of the upper portion of the axis C of the peripheral wall portion 12b of the case 12, the lower edge center (lower edge rear end) 34bc side is brought closer to the upper surface 1a side of the instrument panel 1, and the case 12 The air is disposed on the front side from the upper edge center 34ac side with respect to the axial center C of the peripheral wall portion 12b, so that the air on the upper surface 1a side of the instrument panel 1 on the front side from the axial center C of the peripheral wall portion 12b of the case 12 The inflatable portion 43 of the bag 24 includes a bottom wall 43 a formed from the abutting portion 29 of the vehicle body side wall portion 26, an upper peripheral wall 43 b formed from the front wall portion 34, and a top portion 43 c formed from the peripheral wall portion 12 b of the case 12. Arranged near the top of axis C Is allowed, a substantially triangular pyramidal shape obtained by extending the lower edge center 34bc side to the front side (see the hatched portion in FIG. 13).

  Then, when the airbag 24 moves upward on the rear portion 24b side by receiving the behavior when the inflation is completed or the occupant P is received by the occupant restraint surface 38, the attachment portion of the airbag 24 to the case 12 (on the retainer 10) A rotational moment is generated so that the front end 24a side of the airbag 24 is pushed down around the pressed inflow opening 27 (the peripheral portion of the inflow opening 27). The contact portion 29 (bottom wall 43a) is brought into contact with the upper surface side portion 4 serving as a member on the upper surface 1a side of the instrument panel 1 in front of the case 12 to suppress the rotation thereof. Furthermore, the substantially triangular pyramid-shaped inflated portion 43 that suppresses the upward movement of the airbag 24 on the rear portion 24b side is configured so that the entire front wall portion 43b is composed of a single front wall portion 34. The portion 34 bulges outward to generate a large tension up to the connecting portion of the outer peripheral edge (upper edge 34a and lower edge 34b), and swells into a curved plate shape having rigidity. As a result, the front wall 34 itself expands into a rigid bent plate shape, and deformation that causes wrinkles and narrows the vertical dimension is suppressed. It is possible to reliably regulate the rotation that moves the upper side.

  That is, since the front side of the airbag 24 at the completion of the inflation can be regulated forwardly without extending the front side of the airbag 24 and contacting the windshield W, the capacity of the airbag 24 can be increased. Can be prevented.

  Accordingly, in the passenger seat airbag device M1 of the first embodiment, the increase in the capacity of the airbag 24 can be suppressed, and the upward movement of the rear portion 24b of the airbag 24 when the inflation is completed or when the passenger P is restrained can be suppressed.

  In the first embodiment, the airbag 24 has four sides of the vehicle body side wall portion 26, the outer wall portion 31, the front wall portion 34, and the rear wall portion 36 that can form the peripheral wall 25 by sewing the predetermined edges with each other. It is comprised from the sheet | seat material which has flexibility, automatic sewing becomes possible, and manufacture of the airbag 24 becomes easy. Further, when cutting from a large airbag cloth material 45, the vehicle body side wall portion 26, the outer wall portion 31, the front wall portion 34, and the like, which have a relatively small shape by dividing the peripheral wall 25 of the airbag 24 into four, Since the rear wall portion 36 can be cut, it is easy to arrange each wall portion without a gap, and the generation of the remaining material from the airbag fabric material 45 can be reduced, and the yield of the airbag fabric material 45 is improved. Can do.

  Furthermore, in the first embodiment, as shown in FIG. 13, the front wall portion 34 at the time of completion of expansion has a length LF of the coupling portion 34 bh with the front edge 26 a of the vehicle body side wall portion 26 at the outer periphery viewed from the side surface. The outer wall portion 31 is disposed so as to be longer than the length LH of the coupling portion 34ah with the front edge 31a.

  In such a configuration, the lower edge 34b side disposed along the upper surface 1a side of the instrument panel 1 at the outer peripheral edge of the front wall portion 34 is longer than the upper edge 34a side, and the lower edge 34b side with respect to the upper edge 34a side. Compared to the case where the length ratio is small, the substantially triangular pyramid-shaped inflation portion 43 for suppressing the upward movement of the rear portion 24b of the airbag 24 at the completion of inflation widens the area on the bottom wall 43a side. It becomes a shape. As a result, the substantially triangular pyramid-shaped inflatable portion 43 can disperse the rotational moment that moves the rear portion 24b of the airbag 24 upward when the inflation is completed over a wide area, so that the rear portion 24b of the airbag 24 moves upward. Even if the rotational moment to be moved is large, the upward movement of the airbag 24 on the rear portion 24b side can be suppressed stably.

  As in the airbag 24A shown in FIGS. 15 and 16, the interior of the airbag 24A is reduced so that the volume of the airbag 24A can be reduced without affecting the restraining performance of the passenger P on the passenger restraining surface 38 as much as possible. A tether 49 may be provided. In the case of the illustrated example, a tether 49 is disposed at the rear side portion of the inflow opening 27 in the airbag 24A so as to connect the vehicle body side wall portion 26 and the outer side wall portion 31. In the case of the illustrated example, the tether 49 is configured by joining the tips of two cloth pieces 49a having the base side connected to the vehicle body side wall portion 26 and the outer side wall portion 31 respectively.

  Further, the arrangement relationship between the front wall portion 34 and the axis C of the peripheral wall portion 12b of the case 12 in the airbag 24 when the inflation is completed in the vehicle mounted state is such that the upper edge center 34ac is arranged near the upper portion of the axis C. Thus, it is only necessary that the lower edge center 34bc is positioned forward of the upper edge center 34ac of the front wall 34 with respect to the axis C, and the upper edge center 34ac is the case 12 as in the airbag 24B of FIG. It may be configured to be arranged behind the axis C of the peripheral wall portion 12b.

  Note that the upper edge center (upper edge upper end) 34ac of the front wall portion 34 is preferably disposed on the axis C along the axis C, but if the upward movement on the rear portion 24b side of the airbag 24 can be suppressed. In the upper front-rear area along the axis C of the bottom wall portion 12a of the case 12 (the upper front-rear area along the axis C of the projection opening 22). If the upper edge center (upper edge upper end) 34ac is arranged in the inner), the upward movement of the airbag 24 on the rear portion 24b side can be preferably suppressed. Incidentally, if the center of the upper edge (upper edge upper end) 34ac in the front wall portion 34 is greatly shifted forward from the axis C, the portion of the outer wall portion 31 in the vicinity of the upper portion of the axis C will fold along the horizontal direction. It is difficult to suppress the upward movement of the rear portion 24b of the airbag 24, and the upper edge center (upper edge upper end) 34ac of the front wall portion 34 is larger rearward than the axis C. If they are displaced, a portion of the front wall portion 34 in the vicinity of the upper portion of the axial center C contracts in the front-rear direction by causing wrinkles along the left-right direction, and it is difficult to suppress the upward movement on the rear portion 24b side of the airbag 24. turn into.

  Further, in the passenger seat airbag apparatus M1 of the first embodiment, the top mount type in which the case 12 is provided on the upper surface 1a side of the instrument panel 1 is illustrated, but the passenger seat airbag apparatuses M1C and M1D in FIGS. , M1E, a mid-mount type passenger-side airbag device M1C, M1D mounted at a position where the rear edge 12d side is greatly lowered from the front edge 12c side in the substantially square cylindrical peripheral wall portion 12b of the case 12 , M1E airbags 24C, 24D, 24E may adopt the configuration of the present invention. In addition, regarding the inclination angle from the horizontal direction at the axis C of the peripheral wall portion 12b of the case 12, in the airbag device M1 for the passenger seat according to the first embodiment, as shown in FIG. In the passenger seat airbag apparatus M1C shown in FIG. 18, the inclination angle θ1C is 50 °, and in the passenger seat airbag apparatus M1D shown in FIG. 19, the inclination angle θ1D is 40 °, and the passenger seat air shown in FIG. In the bag device M1E, the inclination angle θ1E is set to 35 °.

  Further, as in the passenger seat airbag device M2 of the second embodiment shown in FIGS. 21 and 22, as the airbag 24F at the time of completion of inflation, the width dimension BL in the left-right direction increases from the rear 24b side toward the front end 24a side. You may comprise so that (refer FIG. 22) may be expanded. That is, as shown in FIG. 23, the vehicle body side wall portion 26 and the outer side wall portion 31 that are opposed to each other in the vertical direction of the peripheral wall 25 of the airbag 24F are formed so that the width dimension in the left-right direction is increased toward the front. May be. In the airbag 24F, when the inflation in the vehicle mounted state is completed, the abutting portion 29 of the vehicle body side wall portion 26 that abuts on the upper surface side portion 4 on the upper surface 1a side of the instrument panel 1 increases the width dimension in the left-right direction. When the inflation is completed, the rotational moment for moving the rear portion 24b of the airbag 24F upward can be dispersed over a wide area. Even if the rotational moment for moving the rear portion 24b of the airbag 24F is large, the rotational moment is stable. The upward movement on the rear portion 24b side of the airbag 24 can be suppressed.

  In the airbag 24F of the second embodiment, although the outer shape of the rear wall portion 36 is the same as that of the first embodiment, the width dimension in the left-right direction between the vehicle body side wall portion 26 and the outer wall portion 31 is set to the front side. Therefore, the front wall portion 34 is configured to have a width dimension in the left-right direction larger than that of the first embodiment.

It is a schematic longitudinal cross-sectional view of the vehicle front-back direction which shows the use condition of the airbag apparatus for passenger seats of 1st Embodiment which concerns on this invention. It is a general | schematic expanded longitudinal cross-sectional view of the front-back direction of the airbag apparatus for front passenger seats of 1st Embodiment. It is the perspective view seen from the front side at the time of inflating the airbag used for 1st Embodiment alone. It is the perspective view seen from the back side at the time of inflating the airbag used for 1st Embodiment alone. It is a top view at the time of inflating the airbag main body of the airbag used for 1st Embodiment alone. It is a longitudinal cross-sectional view along the front-back direction at the time of inflating the airbag used for 1st Embodiment alone. It is an expanded view which shows each wall part which comprises the surrounding wall of the airbag used for 1st Embodiment. It is a figure which shows the arrangement | positioning state at the time of cutting each wall part which comprises the surrounding wall of the airbag used for 1st Embodiment from the fabric material for airbags. It is a figure explaining the manufacturing process of the airbag used for 1st Embodiment. It is a figure explaining the manufacturing process of the airbag used for 1st Embodiment, and shows the process after FIG. It is a figure explaining the manufacturing process of the airbag used for 1st Embodiment, and shows the process after FIG. It is a schematic longitudinal cross-sectional view of the front-back direction which demonstrates in order the action | operation time of the airbag apparatus for front passenger seats of 1st Embodiment. It is a schematic longitudinal cross-sectional view explaining the predetermined | prescribed expansion | swelling site | part of the airbag at the time of the action | operation of the airbag apparatus for passenger seats of 1st Embodiment. FIG. 3 is a schematic plan view showing when the airbag is completely inflated when the passenger seat airbag device according to the first embodiment is activated. It is a perspective view at the time of inflating the airbag in the modification of 1st Embodiment alone. It is a schematic longitudinal cross-sectional view which shows the state at the time of the action | operation of the airbag apparatus for passenger seats using the airbag shown in FIG. It is a schematic longitudinal cross-sectional view which shows the state which the airbag apparatus for passenger seats of the modification of 1st Embodiment act | operated. It is a schematic longitudinal cross-sectional view which shows the state which the airbag apparatus for passenger seats of the other modification of 1st Embodiment act | operated. It is a schematic longitudinal cross-sectional view which shows the state which the airbag apparatus for passenger seats of the further another modification of 1st Embodiment act | operated. It is a schematic longitudinal cross-sectional view which shows the state which the airbag apparatus for passenger seats of another modification of 1st Embodiment act | operated. It is a schematic longitudinal cross-sectional view which shows the time of the action | operation of the airbag apparatus for passenger seats of 2nd Embodiment. It is a schematic top view which shows the time of completion | finish of inflation of the airbag at the time of the action | operation of the airbag apparatus for passenger seats of 2nd Embodiment. It is an expanded view which shows each wall part which comprises the surrounding wall of the airbag used for 2nd Embodiment.

Explanation of symbols

1 ... (Instrument panel) Instrument panel,
1a ... (on the instrument panel)
12 ... Case,
12a ... bottom wall,
12b ... peripheral wall,
24, 24A, 24B, 24C, 24D, 24E, 24F ... airbags,
24a ... front end,
24b ... rear part,
25.
26 ... side wall of vehicle body,
26a / 31a ... the leading edge,
26b, 31b ... trailing edge,
26c, 31c ... left edge,
26d, 31d ... right edge,
29 ... abutting part,
31 ... Outer wall part,
34 ... Front wall,
34a, 36a… Upper edge,
34b, 36b ... lower edge,
36 ... rear wall,
43 ... expansion part,
43a ... bottom wall,
43b ... Perimeter wall,
C: Axis (of the case wall),
M1, M1C, M1D, M1E, M2 ... Airbag device for passenger seat,
P ... Crew.

Claims (3)

The airbag is folded and stored in a case arranged in the instrument panel in front of the passenger seat, and includes an airbag that protrudes from the case and expands and inflates from the upper surface side of the instrument panel to the passenger seat side when inflating gas flows. ,
The airbag device for a passenger's seat is configured such that the case includes a bottom wall portion serving as an attachment site for attaching the airbag, and a peripheral wall portion extending in a cylindrical shape from the periphery of the bottom wall portion,
A portion of the airbag from the vicinity of the bottom wall portion of the case to the front end side when the inflation is completed is disposed on the upper surface side so as to face the vehicle body side wall portion attached to the bottom wall portion and the vehicle body side wall portion. The outer wall is configured to connect the left and right edges to the left and right edges of the vehicle body side wall, and the front end surface of the airbag, and the outer peripheral edge is defined with respect to the front edge of the vehicle body side wall and the outer wall. Are composed of three flexible cloth materials on the front wall part to be joined together,
The vehicle body side wall includes a contact portion that comes off from the case and contacts the upper surface side of the instrument panel on the front side of the case when the airbag has been inflated.
When the inflation of the airbag is completed, the front wall portion is arranged such that the upper edge side of the longitudinal section along the front-rear direction is located near the upper part of the axial center of the peripheral wall portion of the case, and An assistant having an edge side closer to the upper surface side of the instrument panel and being arranged on the front side with respect to the axial center of the peripheral wall portion of the case as compared with the upper edge side. Seat airbag device. The rear end side of the airbag at the time of completion of inflation forms a rear end surface of the airbag, and includes a rear wall portion that joins an outer peripheral edge to the rear edge of the vehicle body side wall portion and the outer wall portion together. Configured
The peripheral wall of the airbag is composed of four flexible cloth materials of the vehicle body side wall, the outer wall, the front wall, and the rear wall,
The vehicle body side wall and the outer wall are formed in a shape that can be coupled by sewing the left and right edges to each other,
The said front wall part and the said rear wall part are each formed in the shape which can carry out a plane sewing to the said vehicle body side wall part and the said outer side wall part, and can couple | bond together an outer periphery. The airbag device for a passenger seat according to 1.   When the expansion is completed, the front wall portion is disposed so that the coupling portion with the front edge of the vehicle body side wall portion at the outer peripheral edge viewed from the side is longer than the coupling portion with the front edge of the outer wall portion. The airbag device for a passenger seat according to claim 1 or 2, wherein the airbag device is for a passenger seat.

Images