Vehicle seats

Abstract

To restrict rotation of a bracket to a seat back frame in a vehicle seat in which the bracket for supporting an air bag is joined to the seat back frame.SOLUTION: A vehicle seat 1 includes a seat cushion 3 and a seat back 4. The seat back includes: a seat back frame 7 having a pair of right and left side frames 11, and an upper frame 12; an air bag module 43 supported on the seat back frame through a bracket 31; a skin member 9 which covers the seat back frame, bracket, and air bag module from a rear surface; and a fragile part 80 which should be opened by expansion of an air bag and is arranged on the skin member. The bracket is joined to the upper frame on an upper edge at a lateral interval from each other, and is joined to the side frames respectively corresponding on right and left edges.SELECTED DRAWING: Figure 4

Description

Technical Field

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[0001] The present invention relates to a front seat vehicle seat provided with an airbag.

Background Art

[0002] In a vehicle, there is a front seat vehicle seat provided with an airbag module that deploys rearward (for example, Patent Document 1). In the vehicle seat of Patent Document 1, the airbag module is supported by an airbag case and coupled to a seat back frame. The airbag case is fastened to a side frame at the left and right edges of the lower end and hooked on a protrusion provided on an upper frame at the center of the upper end.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the airbag deploys rearward, a load acting forward is applied to the airbag case. Since the upper part of the airbag case is hooked on the upper frame at the center of the upper end, the rotation of the upper part of the airbag case is not sufficiently restricted, and there is a problem that the deployment direction of the airbag becomes unstable.

[0005] In view of the above background, an object of the present invention is to restrict rotation of a bracket for supporting an airbag with respect to a seat back frame in a vehicle seat in which the bracket is coupled to the seat back frame.

Means for Solving the Problems

[0006] <{0000033}>To solve the above problems, a vehicle seat (1) comprising a seat cushion (3) and a seat back (4) is provided, wherein the seat back comprises a seat back frame (7) including a pair of left and right side frames (11) extending in the vertical direction and an upper frame (12) connecting the upper ends of both side frames to each other; an airbag module (43) supported on the seat back frame via a bracket (31); a surface member (9) covering the seat back frame, the bracket and the airbag module from the rear; and the surface member having a vulnerable portion (80) at a position facing the airbag module that is to open when the airbag inflates, wherein the bracket is connected to the upper frame at its upper edge with a gap between them to the left and right, and connected to the corresponding side frames at its left and right edges.

[0007] In this embodiment, since the upper edge of the bracket is connected to the upper frame with a gap between it and the left and right sides, the rotation of the bracket relative to the seat back frame can be restricted.

[0008] Furthermore, in the above embodiment, the bracket may consist of a single plate member integrally comprising a pair of left and right upper tongue pieces (34) extending from the upper edge and a pair of left and right lower tongue pieces (35) extending to the left and right from the lower part of the left and right edges.

[0009] According to this embodiment, the bracket can be made lightweight and inexpensive.

[0010] Furthermore, in the above embodiment, the bracket may have a substantially trapezoidal shape with a shorter side on the upper side.

[0011] According to this embodiment, the upper and lower tongue pieces can be shortened, and the bracket can be made lighter.

[0012] Furthermore, in the above embodiment, it is preferable that the upper tongue and the lower tongue pass behind the seat back frame and are welded to the seat back frame.

[0013] According to this embodiment, the forward load applied to the bracket by the deployment of the airbag can be supported by the seat back frame.

[0014] Furthermore, in the above embodiment, the bracket has a recess (41) that is recessed toward the front for housing the airbag module, and it is preferable that the recess overlaps the side frame in a side view.

[0015] In this embodiment, since the recess housing the airbag module overlaps with the side frame, the amount of rearward protrusion of the seatback can be reduced.

[0016] Furthermore, in the above embodiment, a through hole (51) is formed in the bottom wall of the recess, and the airbag module is fastened to the bottom wall by a fastener (50) that passes through the through hole.

[0017] According to this embodiment, the bottom wall of the recess can support the forward load applied to the bracket by the deployment of the airbag.

[0018] Furthermore, in the above embodiment, a through hole (51) is formed in the lower side wall of the recess, and the airbag module is fastened to the side wall by a fastener (50) that passes through the through hole.

[0019] According to this embodiment, the fastener does not protrude forward, and the feeling of a foreign object in the back of the seated occupant can be reduced.

[0020] Furthermore, in the above embodiment, the bottom wall (42) of the recess is preferably a flat plate that is inclined downward and backward with respect to the axial direction of the headrest pillar (28).

[0021] In this embodiment, since the bottom wall of the recess formed in the bracket is sloped backward from top to bottom, the feeling of a foreign object that the bracket imparts to the back of the seated occupant can be reduced.

[0022] In addition, in the above aspect, it is preferable that an edge wall (36) extending forward is provided at the lower edge of the bracket.

[0023] According to this aspect, the rigidity of the bracket can be increased.

[0024] In addition, in the above aspect, it is preferable that a plurality of relief holes (38) are provided in the bracket between the edge wall and the recess.

[0025] According to this aspect, the bracket can be made lighter.

[0026] In addition, in the above aspect, the fragile portion extends horizontally, and a mounting hole (55) penetrating in the thickness direction is provided in the bracket between the upper edge and the recess, and a first force cloth (81) having one end locked to the mounting hole and the other end sutured to the upper skin member constituting the fragile portion is provided.

[0027] According to this aspect, the fragile portion can be opened by applying the load due to the inflation of the airbag to the first force cloth. In addition, since one end of the first force cloth is coupled near the airbag module, the load is easily transmitted to the first force cloth.

[0028] In addition, in the above aspect, the fragile portion extends horizontally, and a second force cloth (82) having one end locked to the edge wall and the other end sutured to the lower skin member constituting the fragile portion is provided.

[0029] According to this aspect, the fragile portion can be opened by applying the load due to the inflation of the airbag to the second force cloth. In addition, since one end of the second force cloth is coupled near the airbag module, the load is easily transmitted to the second force cloth.

[0030] In addition, in the above aspect, it is preferable that a blower (56) for blowing air is provided on the front surface of the bracket.

[0031] According to this embodiment, the bracket supporting the airbag can also serve as the bracket supporting the blower, thus reducing the number of parts in the vehicle seat. [Effects of the Invention]

[0032] According to the above embodiment, in a vehicle seat in which a bracket for supporting an airbag is coupled to a seat back frame, it becomes possible to restrict the rotation of the bracket relative to the seat back frame.

[0033] Furthermore, if the bracket consists of a single plate member integrally comprising an upper tongue and a lower tongue, the bracket can be made lightweight and inexpensive.

[0034] Furthermore, if the bracket has a roughly trapezoidal shape with a shorter side on the upper side, the upper and lower tongue pieces can be shortened, and the bracket can be made lighter.

[0035] Furthermore, in a configuration where the upper and lower tongue pieces pass behind the seat back frame and are welded to the seat back frame, the forward load applied to the bracket by the deployment of the airbag can be supported by the seat back frame.

[0036] Furthermore, the bracket has a recessed area facing forward to accommodate the airbag module, and in a configuration where the recess overlaps the side frame in a side view, the amount of rearward protrusion of the seatback can be reduced.

[0037] Furthermore, in a configuration where a through-hole is formed in the bottom wall of the recess and the airbag module is fastened to the bottom wall by fasteners passing through the through-hole, the bottom wall of the recess can support the forward load applied by the deployment of the airbag.

[0038] Furthermore, in a configuration where a through-hole is formed in the lower side wall of the recess, and the airbag module is fastened to the lower side wall of the recess by a fastener that passes through the through-hole, the fastener does not protrude forward, thus reducing the feeling of a foreign object on the back of the seated occupant.

[0039] Furthermore, if the bottom wall of the recess is in the shape of a flat plate with an inclination that recedes from the top to the bottom with respect to the axial direction of the headrest pillar, the feeling of a foreign object that the bracket imposes on the back of the seated occupant can be reduced.

[0040] Furthermore, if an edge wall extending forward is provided at the lower edge of the bracket, the rigidity of the bracket can be increased.

[0041] Furthermore, if the bracket is provided with multiple weight-reducing holes between the edge wall and the recess, the bracket can be made lighter.

[0042] Furthermore, in an embodiment having a first reinforcing cloth, one end of which is locked into the mounting hole and the other end of which is sewn to the upper surface member constituting the weak part, the weak part can be opened by applying a load due to the inflation of the airbag to the first reinforcing cloth. Since one end of the first reinforcing cloth can be connected near the airbag module, the load is more easily transmitted to the first reinforcing cloth.

[0043] Furthermore, in an embodiment having a second reinforcing cloth, one end of which is locked to the edge wall and the other end of which is sewn to the lower surface material constituting the weak area, the weak area can be opened by applying a load due to the inflation of the airbag to the second reinforcing cloth. Since one end of the second reinforcing cloth can be connected near the airbag module, the load is more easily transmitted to the second reinforcing cloth.

[0044] Furthermore, in a configuration in which a blower for supplying air is provided on the front of the bracket, the bracket supporting the airbag can also serve as a bracket for supporting the blower, thus reducing the number of parts in the vehicle seat. [Brief explanation of the drawing]

[0045] [Figure 1] Diagram illustrating the deployment of airbags in vehicle seats. [Figure 2] Rear view of the frame of a vehicle seat. [Figure 3] Rear view of a vehicle seat [Figure 4] Cross-sectional view of the vehicle seat in the first embodiment, shown from IV to IV in Figure 3. [Figure 5] Cross-sectional view of a vehicle seat in the second embodiment. [Figure 6] Cross-sectional view of a vehicle seat in the third embodiment. [Figure 7] Cross-sectional view of a vehicle seat according to another embodiment, in which (A) the arrangement of the second reinforcing fabric and (B) the arrangement of the first reinforcing fabric differ from the first embodiment. [Figure 8] Rear view of a vehicle seat according to another embodiment, in which the pad member is provided with (A) two intersecting slits and (B) a roughly H-shaped slit. [Figure 9] (A) Cross-sectional view of a vehicle seat according to another embodiment, in which a backboard having a thin-walled portion and (B) a backboard having a slit are provided. [Figure 10] (A) Cross-sectional view of a vehicle seat according to another embodiment in which the outer case is omitted, and (B) the retainer and lid are omitted. [Modes for carrying out the invention]

[0046] Two embodiments of the vehicle seat according to the present invention applied to an automobile will be described below with reference to the drawings.

[0047] <<First Embodiment>> As shown in Figure 1, the first embodiment of the vehicle seat 1 according to the present invention constitutes the front seat of the first row of an automobile. The seat has a seat cushion 3 provided on the floor 2 of the automobile, a seat back 4 supported at the rear of the seat cushion 3, and a headrest 5 provided on the upper part of each seat back 4.

[0048] As shown in Figure 2, the seat back 4 comprises a seat back frame 7 as a skeleton, a pad member 8 supported by the seat back frame 7, and a surface member 9 provided on the surface of the pad member 8 and constituting the outer surface of the seat back 4.

[0049] The seat back frame 7 has a pair of left and right side frames 11 that extend vertically, an upper frame 12 that extends horizontally and connects to the upper ends of the left and right side frames 11, and a lower frame 13 that extends horizontally and connects to the lower parts of the left and right side frames 11. The upper parts 14 of each side frame that make up the upper part of each left and right side frame 11 and the upper frame 12 are formed by bending a single circular pipe into an inverted U-shaped frame. The lower parts 15 of each side frame that make up the lower part of each side frame 11 are each formed from sheet metal members and welded to both ends of the pipe. Support members 16 are stretched across the left and right side frames 11 in pairs, vertically. Plate-shaped pressure receiving members 17 that support the occupant's back so that it can move backward are connected to the front side of the support members 16.

[0050] As shown in Figure 2, the upper part of the seat back frame 7 is formed by the upper frame 12 and the upper parts 14 of the left and right side frames, and has a roughly trapezoidal shape when viewed from the rear.

[0051] The upper frame 12 has a planar front surface 21 on the front side of the intermediate portion on both the left and right sides. The front surface 21 is formed by compressing and deforming a circular pipe material so that its cross-section becomes semicircular. A pair of pillar support brackets 22 are welded to the front surface 21. Each pillar support bracket 22 is formed in the shape of a rectangular tube with both ends open. Each pillar support bracket 22 has its respective axis extending approximately vertically and is positioned with a gap between them to the left and right. A pillar support member 23 is inserted into the pillar support bracket 22. The pillar support member 23 has a cylindrical portion 24 and a flange portion 25 that protrudes laterally from the upper end of the cylindrical portion 24. The axial direction of the cylindrical portion 24 is generally parallel to the extending direction of the side frame 11.

[0052] The headrest 5 comprises a headrest body 27 and a pair of left and right pillars 28 protruding from the headrest body 27. By fitting the pillars 28 into the cylindrical portion 24, the headrest 5 is supported on the seat back frame 7 so as to be displaceable along the axis of the cylindrical portion 24. The flange portion 25 is provided with locking means (not shown) for fixing the insertion position of the pillars 28 relative to the cylindrical portion 24. The headrest 5 is fixed in a predetermined position by the locking means.

[0053] Brackets 31 are connected to both side frames 11 and the upper frame 12. The brackets 31 are located in the upper half of the seat back frame 7. The brackets 31 are generally plate-shaped and oriented in the front-rear direction. The brackets 31 are made from a single plate member formed by drawing from a single sheet metal, and consist of a plate-shaped main part 30 having a main surface oriented in the front-rear direction, a pair of left and right upper tongue pieces 34 extending upward in a band shape from the upper edge of the main part 30, and a pair of left and right lower tongue pieces 35 extending outward from the left and right lower parts of the main part 30. The main part 30 consists of a central part 32 that constitutes its upper part and a base part 33 provided below the central part 32.

[0054] The central section 32 has a roughly trapezoidal shape when viewed from the rear, with its width narrowing from side to side towards the top. The central section 32 is roughly the same shape as the upper part of the seat back frame 7.

[0055] The upper tongue pieces 34 extend upward from the left and right ends of the upper edge of the central portion 32, and are formed with a gap between them. The upper tongue pieces 34 are arranged symmetrically with respect to the center line in the left-right direction of the seat back frame 7. At their upper ends, the upper tongue pieces 34 are curved to follow the rear surface of the upper frame 12 and are welded to the upper frame 12. The lower tongue pieces 35 are curved to follow the rear surface of the upper part 14 of the side frame and are welded to the side frame 11. In this embodiment, the upper tongue pieces 34 are welded to the upper part of the rear surface of the upper frame 12 (dashed line portion in Figure 2), and the lower tongue pieces 35 are welded to the left and right outer portions of the rear surface of the upper part 14 of the side frame (dashed line portion in Figure 2).

[0056] As shown in Figure 4, the lower edge of the base portion 33 is provided with an edge wall 36 that extends forward along its entire lower edge. A pair of weak portions 37 are formed at the boundary between the base portion 33 and the lower tongue piece 35. In this embodiment, the bracket 31 is bent so as to protrude forward in a U-shape at the weak portions 37. Multiple weight-reducing holes 38 are formed in appropriate places on the base portion 33 to lighten the bracket 31.

[0057] On the rear surface of the central portion 32, a recess 41 is formed approximately in the center, indenting forward. The bottom of the recess 41 overlaps the side frame 11 in a side view. The recess 41 is defined by a flat recess bottom wall 42 that generally faces in the front-to-back direction, and side walls surrounding the recess bottom wall 42. In a side view, the recess bottom wall 42 is inclined downward and backward with respect to the axial direction of the pillar 28. In a rear view, the recess bottom wall 42 has a roughly rectangular shape extending left and right, and the recess 41 has a roughly rectangular parallelepiped shape.

[0058] A resin outer case 40 is housed in the recess 41. The outer case 40 is roughly rectangular in shape, extending from left to right. The outer case 40 has a bottom wall 40B facing in the front-to-back direction and side walls 40S surrounding the bottom wall 40B. The outer case 40 has a housing recess 40R formed in it, defined by the bottom wall 40B and the side walls 40S. The housing recess 40R is recessed toward the front and opens toward the rear. Locking claws 40C that protrude outward in the vertical direction are provided at predetermined positions on the upper and lower surfaces of the outer case 40. The upper and lower walls of the recess 41 are provided with locking holes that penetrate to positions corresponding to the locking claws 40C and engage with the locking claws 40C.

[0059] A forward-projecting fitting projection 40P is provided at a predetermined position on the front surface of the outer case 40, and a positioning hole is provided in the bottom wall 42 of the recess that penetrates to a position corresponding to the fitting projection 40P. When connecting the outer case 40 to the recess 41, the outer case 40 can be easily positioned correctly by engaging the locking claw 40C with the locking hole and inserting the fitting projection 40P into the positioning hole.

[0060] The outer case 40 is provided with an extension portion 40E that extends substantially perpendicular to the side wall 40S at the opening edge. The extension portion 40E extends outward beyond the opening edge that defines the opening portion of the recess 41 of the bracket 31. At least a portion, preferably all, of the opening edge of the recess 41 is covered from the rear by the extension portion 40E.

[0061] The airbag module 43 is housed in the housing recess 40R. The airbag module 43 abuts against the bottom wall 40B and is contained within the recess 41. The airbag module 43 comprises an airbag 45, an inflator 46 for inflating the airbag 45, and a case 47 for housing the airbag 45 and the inflator 46.

[0062] The case 47 is roughly rectangular in shape and includes a retainer 48 with a recess that opens toward the rear, and a lid 49 that closes the opening of the recess.

[0063] The inflator 46 is roughly cylindrical in shape. The inflator 46 is housed in a recess of the retainer 48, more specifically extending laterally from its lower front corner, and is coupled to the retainer 48. The airbag 45 is housed in the recess of the retainer 48 in a folded state. The airbag 45 is positioned to cover the inflator 46 from above.

[0064] The retainer 48 includes an upper wall 44 that defines its recess. The upper wall 44 has a downward-facing surface and is vertically opposed to the inflator 46. An airbag 45 is positioned between the upper wall 44 and the inflator 46.

[0065] The lid 49 is made of resin. The lid 49 has a roughly rectangular plate-shaped lid body 49B with a main surface facing in the front-rear direction, and a lid locking portion 49L that extends forward from the top, bottom, left, and right ends of the lid body 49B and has locking claws at its ends. Locking holes are provided in the top, bottom, left, and right walls of the retainer 48, and the lid 49 is connected to the retainer 48 by the engagement of the locking claws with these locking holes. A groove extending from left to right is formed on the inside of the lid body 49B. The lid body 49B is thinner in the groove 53 than in other parts. The groove 53 extends vertically from the left and right ends to the top and bottom ends of the lid body 49B.

[0066] A hinge 49H is formed at the connection between the lid body 49B and the lid locking portion 49L, and the lid 49 is hinged to the upper and lower edges of the opening of the retainer 48. When a load is applied to the lid 49 due to the inflation of the airbag 45, the lid 49 splits open along the groove 53. Thus, the groove 53 functions as a deployment opening. When the lid 49 splits open, the upper rear and lower rear sides of the lid 49 rotate about their upper and lower edges as axes, respectively, and the case 47 opens. Since the opening edge of the recess 41 of the bracket 31 is covered from the rear by the extension 40E, when the airbag 45 inflates, the airbag 45 does not directly contact the opening edge of the recess 41, and damage to the airbag 45 is prevented.

[0067] The front surface of the retainer 48 is provided with a male threaded portion 50 that protrudes forward. The bottom wall of the outer case 40 and the recessed bottom wall 42 are provided with through holes 51 and 44T, respectively, that penetrate to positions corresponding to the male threaded portion 50. After passing the male threaded portion 50 through the two through holes 51 in the outer case 40 and the recessed bottom wall 42, the airbag module 43 is fastened to the bracket 31 together with the outer case 40 by attaching a nut 52 to the male threaded portion 50. After fastening, the case 47 is positioned so that it overlaps the side frame 11 when viewed from the side.

[0068] A pair of mounting holes 55, extending through in the thickness direction, are formed on the upper part of the central portion 32 and above the recess 41.

[0069] A blower 56 is attached to the front of the recessed bottom wall 42. The blower 56 comprises a blower case 57, a motor 58 housed in the blower case 57, and a fan 60 connected to the rotating shaft 59 of the motor 58.

[0070] The blower case 57 has a substantially rectangular parallelepiped shape with surfaces facing in the front-rear direction. An opening is formed in the front wall of the blower case 57. A through hole is formed in the blower case 57 at a predetermined position, penetrating from front to back, and a screw hole is formed in the recess bottom wall 42 at a position corresponding to the through hole. The blower case 57 is connected to the front surface of the recess bottom wall 42, approximately in the left-right direction, by screws that pass through the through hole and connect to the screw hole. The front wall of the blower case 57 is approximately parallel to the recess bottom wall 42, and the blower case 57 is positioned between the left and right pillars 28. In this embodiment, the width of the blower case 57 in the front-rear direction is sufficiently thin, and the front wall of the blower case 57 is located behind the pillars 28 in a side view.

[0071] A cable (not shown) is connected to the motor 58 to supply power from outside the vehicle seat 1. The motor 58 is driven by the supplied power, causing the fan 60 to rotate. The rotation of the fan 60 causes air to be ejected forward.

[0072] The pad member 8 is formed from a flexible cushioning material such as polyurethane foam. The pad member 8 comprises a front portion 65 that forms a backrest surface 64 facing the occupant's back, an upper portion 66 extending rearward from the upper edge of the front portion 65, side portions 67 extending rearward from the left and right side edges of the front portion 65, and a rear portion 68 extending downward from the rear end of the upper portion 66.

[0073] The front section 65 extends vertically and has a roughly rectangular plate shape with a predetermined thickness in the front-to-back direction. The rear surface of the front section 65 abuts against the front surfaces of both side frames 11, the upper frame 12, and the pressure receiving member 17. A ventilation hole 69 is formed in the front section 65, penetrating from front to back in front of the blower 56. Air injected from the blower 56 passes through the ventilation hole 69 and reaches the backrest surface 64.

[0074] In a side view, the upper portion 66 extends rearward from the upper edge of the front portion 65 to the rear edge of the upper frame 12. The upper portion 66 has through holes 70 that penetrate vertically to the portions corresponding to the upper ends of the left and right pillar support brackets 22. The corresponding pillar support brackets 22 are inserted into each through hole 70.

[0075] Each side section 67 extends rearward from the left and right side edges of the front section 65 along the left and right outer surfaces of the side frame 11, reaching the rear surface of the side frame 11.

[0076] The rear portion 68 extends downward from the rear end of the upper portion 66 and reaches the lower end of the bracket 31. A first slit 71 is formed in the rear portion 68, penetrating in the thickness direction behind the recess bottom wall 42, more specifically behind the groove 53. The first slit 71 extends in the penetrating direction generally perpendicular to the recess bottom wall 42. As shown in Figure 3, the first slit 71 extends in the left-right direction from between the left side frame 11 and the left wall of the recess 41 to between the right side frame 11 and the right wall of the recess 41. Preferably, the width of the first slit 71 in the left-right direction is greater than the width of the recess 41 in the left-right direction and greater than the width of the central portion 32 in the left-right direction.

[0077] The rear portion 68 has two second slits 72 that penetrate in the thickness direction behind each mounting hole 55. Each second slit 72 is preferably inclined in the penetrating direction so as to approach the opening on the surface of the first slit 71 towards the rear. The width of each second slit 72 in the left-right direction is approximately equal to that of the mounting hole 55 in the left-right direction.

[0078] As shown in Figures 3 and 4, the surface member 9 is formed in a bag shape by combining a front sheet material 75 that integrally covers the front portion 65, top portion 66, side portion 67, and rear portion 68 of the pad member 8, and a rear sheet material 76 that constitutes the rear surface of the seat back 4.

[0079] The front sheet material 75 is formed by sewing together multiple pieces made of sheet-like material such as cloth or leather. The front sheet material 75 has a front piece that covers the surface of the front portion 65, side pieces 77 that cover the surfaces of the left and right side portions 67, and an upper piece 78 that covers the surfaces of the top portion 66 and the rear portion 68. The upper edge of the front piece and the front edge of the upper piece 78, the left and right side edges of the front piece and the front edges of the side pieces 77, and the upper edge of the side pieces 77 and the left and right side edges of the upper piece 78 are sewn together. The rear sheet material 76 is formed by a rear piece 79 made of sheet-like material. The rear piece 79 has a roughly rectangular shape that extends vertically. The upper edge of the rear piece 79 and the rear end edge of the upper piece 78 are sewn together to form a seam 80. The seam 80 functions as a weak point that breaks with a smaller load compared to other seams.

[0080] The suture portion 80 is located behind the opening at the rear end of the first slit 71. The suture portion 80 is located behind the upper half of the recess 41, more specifically, approximately behind the upper wall 44 of the retainer 48. Therefore, the suture portion 80 is located above the inflator 46. The suture portion 80 is formed to extend to the left and right. The left and right ends of the suture portion 80 are located to the left and right outside the recess 41, respectively. Preferably, the left and right ends of the suture portion 80 are located to the left and right outside the main portion 30 of the bracket 31.

[0081] The upper side edges of the rear piece 79 and the side pieces 77 are sewn together. The lower side edges of the rear piece 79 and the side pieces 77 are connected in an openable and closable manner by fasteners, hook-and-loop fasteners, snap-fit ​​fasteners, etc. This allows the upholstery member 9 to be attached to the seat back 4 by connecting the rear piece 79 and the side pieces 77 after the upholstery member 9 has been placed over the seat back frame 7 and the pad member 8.

[0082] Between the bracket 31 and the skin member 9, a first reinforcing fabric 81 and a second reinforcing fabric 82 are provided to restrict the deployment direction of the airbag 45. The first reinforcing fabric 81 and the second reinforcing fabric 82 are each formed of a sheet-like material that is less elastic than the skin member 9. One end of the first reinforcing fabric 81 and the second reinforcing fabric 82 are each connected to the bracket 31 above and below the airbag module 43. A pair of left and right clips 83 are connected to one end of the first reinforcing fabric 81. Each clip 83 is fitted into a corresponding mounting hole 55. A J-shaped hook 84 is connected to one end of the second reinforcing fabric 82. Each hook 84 is hooked to the edge wall 36. The first reinforcing fabric 81 extends rearward from each clip 83, passes through the second slit 72, and reaches the vicinity of the upper side of the suture 80. The second reinforcement fabric 82 extends rearward along the lower and rear edges of the rear portion 68, and extends upward to the vicinity of the lower side of the seam 80. The other end of the first reinforcement fabric 81 and the lower edge of the upper piece 78 are sutured to each other in the vicinity of the seam 80. The other end of the second reinforcement fabric 82 and the upper edge of the rear piece 79 are sutured to each other in the vicinity of the seam 80.

[0083] Next, the operation of the vehicle seat 1 will be described. In the event of a frontal collision or the like, the rear seat occupant will experience forward acceleration and load. To detect such load applied to the rear seat occupant, for example, a sensor 92 may be provided to detect the load applied to the seat belt 91 worn by the rear seat occupant.

[0084] When the acceleration of the rear-seat occupants or the load applied to the seat belt 91 exceeds a predetermined value, gas is released from the inflator 46. The airbag 45, which has inflated upward by the gas released from the inflator 46, is guided rearward by the lower surface of the upper wall 44 of the retainer 48. Therefore, the upper wall 44 of the retainer 48 functions as a guide wall that guides the inflation direction of the airbag 45. The rearward inflation of the airbag 45 applies a load to the cover 49, causing the cover 49 to tear open in the groove 53, and the case 47 of the airbag module 43 opens. The airbag 45 protrudes from the case 47, is guided by the first reinforcement fabric 81 and the second reinforcement fabric 82, passes through the first slit 71, and reaches the seam 80. At this time, the seam 80 ruptures due to the load from the airbag 45, and an opening is formed in the skin member 9. The airbag 45 protrudes from the rear of the seatback 4 through an opening, inflates rearward and diagonally upward, and then deploys to extend downward and rearward. When deployed, the airbag 45 has an upward-convex arch shape (dashed line in Figure 1). Therefore, the airbag 45 can be deployed in front of the occupant's upper body regardless of the distance between the passenger seat 1 and the rear seat. If the rear seat is close to the passenger seat 1, the airbag 45 is folded, which reduces the rearward load on the occupant due to the deployment of the airbag 45.

[0085] Next, the effects of the vehicle seat 1 will be explained. As shown in Figure 4, the airbag module 43 is covered by the surface material 9 and positioned inside the seat back 4. Since the airbag module 43 is not exposed on the rear surface of the seat back 4, the design of the vehicle seat 1 can be improved. In addition, since the airbag module 43 is covered by the pad material 8, the feel of the back of the vehicle seat 1 is improved.

[0086] Since the airbag module 43 is housed in the recess 41, the amount of protrusion of the airbag module 43 from the rear of the seat back 4 can be reduced. The front part of the case 47 of the airbag module 43 is positioned below the upper frame 12 and overlaps with the side frame 11 in a side view. Therefore, the airbag module 43 is positioned further forward relative to the seat back frame 7 compared to when the entire case 47 is located behind the side frame 11. Thus, the amount of rearward protrusion of the seat back 4 can be reduced.

[0087] The airbag 45 inflates along the first slit 71 by gas from the inflator 46. This inflation applies an upward load to the first reinforcing fabric 81 and a downward load to the second reinforcing fabric 82. The loads applied to the first and second reinforcing fabrics 81 and 82 are transmitted to the seam 80, and the areas near the upper and lower parts of the seam 80 of the skin member 9 are pulled from above and below, respectively, causing the seam 80 to open. The airbag 45 deploys behind the seat back 4 through the first slit 71 and the opened seam 80.

[0088] The formation of the second slit 72 allows the first reinforcing fabric 81 to be positioned so as to extend approximately linearly from behind the mounting hole 55 to in front of the suture portion 80. This shortens the length of the first reinforcing fabric 81 in the front-to-back direction. Consequently, the load applied to the first reinforcing fabric 81 is more easily transmitted to the suture portion 80, and the suture portion 80 becomes more likely to open.

[0089] The second reinforcement fabric 82 extends along the lower and rear edges of the pad member 8, reaching the vicinity of the lower portion of the seam 80. Therefore, after assembling the pad member 8 and the cover member 9 and placing it over the seat back frame 7, the hook 84 can be attached to the edge wall 36 from below. Thus, the second reinforcement fabric 82 is easy to install.

[0090] The first reinforcing fabric 81 is provided with a pair of clips 83, and by inserting the clips 83 into the mounting holes 55, the first reinforcing fabric 81 can be easily connected to the bracket 31. Furthermore, because the first reinforcing fabric 81 is connected to two mounting holes 55 that are aligned left and right, the area of ​​the first reinforcing fabric 81 that receives the load from the inflation of the airbag 45 is widened in the left-right direction, making it easier for the load from the inflation of the airbag to be applied to the suture portion 80.

[0091] Since one end of the first reinforcing fabric 81 and the second reinforcing fabric 82 is locked near the airbag module 43 of the bracket 31, the load is easily transmitted to the first reinforcing fabric 81 and the second reinforcing fabric 82. In addition, the first reinforcing fabric 81 and the second reinforcing fabric 82 allow the load from the deployment of the airbag 45 to be concentrated at the seam 80, and the seam 80 can be reliably ruptured when the airbag 45 is deployed.

[0092] The airbag 45 inflates backward relative to the recess 41. When viewed from the rear, the central part of the suture 80 overlaps with the recess 41, making it easy for the backward-inflated airbag 45 to pass through the suture 80.

[0093] As shown in Figure 3, the seam 80 extends horizontally across the rear surface of the seat back 4. Therefore, the width (lateral width) of the airbag 45 when deployed can be increased, allowing for a wider range of lateral positioning of rear-seat occupants. Furthermore, the left and right ends of the seam 80 are located to the left and right of the recess 41, respectively, and preferably, the left and right ends of the seam 80 are located to the left and right of the main part 30 of the bracket 31. By increasing the width of the seam 80 in this way, the airbag 45 that inflates to the rear can pass through the seam 80 more easily. In addition, the width of the airbag 45 when deployed can be increased, allowing for a wider range of lateral positioning of rear-seat occupants.

[0094] As shown in Figure 2, the bracket 31 is connected to the upper frame 12 at the left and right upper tongue pieces 34 with a gap between them. Therefore, rotation of the upper part of the bracket 31 with an axis approximately in the vertical direction is restricted. As a result, the bracket 31 is less likely to come off the seat back frame 7, and the connection between the bracket 31 and the seat back frame 7 can be made stronger.

[0095] Since the bracket 31 is formed from a single plate member, it can be manufactured lightly and inexpensively. The bracket 31 has a roughly trapezoidal shape with a shorter side on the upper side, and is roughly the same shape as the upper part of the seat back frame 7. Therefore, the upper tongue 34 and lower tongue 35 can be shortened. In addition, the upper right and upper left corners of the bracket 31 are omitted, which reduces the weight of the bracket 31.

[0096] The deployment of the airbag 45 and the collision of the rear-seat occupants impose a forward load on the bracket 31. Since the upper tongue 34 is positioned along the rear surface of the upper frame 12 and the lower tongue 35 is positioned along the rear surface of the upper part 14 of the side frame, the upper tongue 34 and the lower tongue 35 are subjected to a rearward load from the rear surface of the upper frame 12 and the rear surface of the upper part 14 of the side frame. Therefore, the bracket 31 is supported by the seat back frame 7 and can resist the forward load.

[0097] The airbag module 43 is fastened to the recessed bottom wall 42. When the airbag 45 deploys, a forward load is applied to the airbag module 43. Because the airbag module 43 is fastened to the recessed bottom wall 42, the bracket 31 resists this load, and the airbag module 43 is supported by the bracket 31. In addition, because the airbag module 43 is fastened to the recessed bottom wall 42, it becomes easier to fasten the airbag module 43 to the bracket 31.

[0098] The airbag module 43 is located in the upper half of the seatback frame 7. Therefore, because the airbag module 43 is positioned in front of the upper body of the rear seat occupant, the airbag 45 can be deployed in front of the upper body of the rear seat occupant, thereby protecting the upper body of the rear seat occupant. In addition, because the seam 80 is located behind the upper half of the recess 41, the airbag 45 can be deployed from a higher position on the seatback 4.

[0099] The bracket 31 is positioned behind the pillar 28. Therefore, the bracket 31 can be installed without changing the position of the pillar 28.

[0100] When seated, the load applied may cause the occupant's back to move behind the axis of the pillar 28. Even in this case, since the recessed bottom wall 42 is inclined downward and backward, the recessed bottom wall 42 does not interfere with the occupant's back, and the feeling of a foreign object being felt by the occupant can be reduced. In addition, since the bracket 31 is positioned above the pressure-receiving member 17, the bracket 31 can prevent the occupant from feeling a foreign object being felt on their back.

[0101] Since the base portion 33 connects the side frame 11 from left to right via the lower tongue piece 35, it functions as a cross member that increases the rigidity of the seat back frame 7. To increase the rigidity of the seat back frame 7, the base portion 33 is preferably connected to the side frame 11 at a position between 5 percent and 20 percent of the total length of the side frame 11 from the upper end of the side frame 11. If the side frame 11 has bent portions 93 that bend inward to the left and right, it is preferable that the base portion 33 is connected to the side frame 11 above the bent portions 93.

[0102] The rigidity of the base portion 33 is enhanced by the edge wall 36. The lower wall defining the recess 41 and the edge wall 36 face each other, and the lower part of the bracket 31 forms a U-shape facing forward in a side view, further increasing its rigidity. By increasing the rigidity of the lower part of the bracket 31, the connection between the side frames 11 becomes stronger, and the rigidity of the seat back frame 7 can be further increased.

[0103] By providing a blower 56 on the vehicle seat 1, air is blown from the ventilation holes 69 in the seat back 4 towards the seated occupant, thereby improving seating comfort. Since the blower 56 is coupled to the bracket 31 that supports the airbag 45, there is no need to provide a bracket 31 to support the blower 56, which reduces the number of parts and simplifies the vehicle seat 1.

[0104] Furthermore, when the airbag 45 deploys, the rear-seat occupant may collide with the airbag 45, and a forward load may be applied to the bracket 31. At this time, the deformation of the weak point 37 of the bracket 31 absorbs the forward load applied to the bracket 31. Therefore, the load applied to the rear-seat occupant can be reduced. In addition, it is possible to prevent the load from being applied to the occupant of the vehicle seat 1 as a result of the rear-seat occupant's collision.

[0105] <<Second Embodiment>> In the vehicle seat 1 according to the second embodiment, the airbag module 43 differs from the first embodiment in that, as shown in Figure 5, the lower part of the recess 41 is defined and fastened to the lower wall 96 of the recess which faces vertically. The male threaded portion 50 provided on the airbag module 43 extends downward. A through hole 51 is provided in the lower wall 96 of the recess at a position corresponding to the male threaded portion 50. A through hole 40T is provided in the side wall 40S of the outer case 40 at a position corresponding to the male threaded portion 50. The airbag module 43 is fastened to the lower wall 96 of the recess by passing the male threaded portion 50 through the through holes 51 and 41T respectively and connecting a nut 52 to the male threaded portion 50. The airbag module 43 may be fastened to any of the side walls surrounding the bottom wall 42 of the recess.

[0106] Since the airbag 45 deploys above and behind the seatback 4, a downward load may be applied to the recess 41 when the airbag 45 deploys. By fastening the airbag module 43 to the lower wall 96 of the recess, the bracket 31 can resist the downward load during deployment. In addition, since the male screw portion 50 does not protrude forward, the feeling of a foreign object on the back of the seated occupant can be reduced.

[0107] <<Third Embodiment>> In the vehicle seat 1 according to the third embodiment, as shown in Figure 6, the second slit 72 is not provided compared to the first embodiment, and only the arrangement of the first reinforcing fabric 81 and the second reinforcing fabric 82 is different. The first reinforcing fabric 81 is fixed at one end to the mounting hole 55 by a clip 83, extends downward along the back surface of the pad member 8, and reaches the stitching portion 80 through the first slit 71. The second reinforcing fabric 82 is hooked at one end to the edge wall 36 by a hook 84, extends upward along the back surface of the pad member 8, and reaches the stitching portion 80 through the first slit 71. Even with this arrangement, the first reinforcing fabric 81 and the second reinforcing fabric 82 restrict the deployment direction of the airbag 45 from above and below, respectively, so that the deployment direction of the airbag 45 is controlled to face the stitching portion 80.

[0108] This concludes the description of the specific embodiments, but the present invention is not limited to the above embodiments and can be broadly modified and implemented. For example, the shape of the bracket 31 is not limited to the above embodiments and can be changed as appropriate. In the above embodiments, the second reinforcing cloth 82 was hooked to the edge wall 36 of the bottom portion 33 at one end, but it may be fitted into the weight-reducing hole 38 by a clip, for example. In the above embodiments, the vehicle seat 1 was provided with the first reinforcing cloth 81 and the second reinforcing cloth 82, but it may also be provided with either the first reinforcing cloth 81 or the second reinforcing cloth 82. Furthermore, in the first embodiment, as shown in Figure 7(A), only the second reinforcing cloth 82 may be modified to follow the back surface of the pad member 8, or only the first reinforcing cloth 81 may be modified to follow the back surface of the pad member 8, as shown in Figure 7(B).

[0109] In the above embodiment, the suture portion 80 was formed to extend left and right on the rear surface of the seat back 4. However, by dividing the side piece 77 into upper and lower parts and providing both the left and right ends of the suture portion 80 on the left and right outer surfaces of the side portion 67, the suture portion 80 may be formed to extend left and right from both the left and right sides of the seat back 4 through the rear surface.

[0110] Furthermore, although the first slit 71 was formed to extend left and right in the pad member 8 in the above embodiment, the invention is not limited to this embodiment. A third slit 100 intersecting the first slit 71 may be provided in the pad member 8 (Figure 8(A)). In addition, a third slit 101 extending vertically from each end of the first slit 71 may be provided (Figure 8(B)). By providing the third slits 100 and 101, the pad member 8 can be opened more easily around the first slit 71, thereby shortening the time required to deploy the airbag 45.

[0111] Furthermore, in the above embodiment, a rear seat material 76 formed of a sheet-like member was provided on the rear surface of the seat back 4, but as shown in Figure 9(A), a backboard 110 made of resin or the like may be provided instead of the rear seat material 76. The backboard 110 is formed in a plate shape having main surfaces at the front and rear. The upper end of the backboard 110 bends rearward along the rear surface portion 68 and extends upward. The backboard 110 is supported by the side frame 11. A thin-walled portion 111, which is thinner in thickness, is formed on the upper part of the backboard 110 so as to extend left and right when viewed from the rear. The thin-walled portion 111 is preferably formed approximately behind the groove 53 of the airbag module 43. When the airbag 45 deploys, a load is applied from the airbag 45 to the backboard 110. Due to this load, the backboard 110 bends rearward at the thin-walled portion 111. The bending of the backboard 110 creates a gap between the backboard 110 and the surface material 9 covering the rear portion 68. The airbag 45 deploys to the rear of the seatback 4 through this gap.

[0112] Furthermore, as shown in Figure 9(B), the backboard 120 may be provided with a slit 121 that tears open due to the load received from the airbag 45 when the airbag 45 is deployed. The slit 121 is located behind the airbag module 43. The slit 121 may also be a groove formed on the front surface of the backboard 120. When viewed from the rear, the slit 121 may have a roughly H-shape, including portions extending left and right and portions extending up and down from both ends thereof. When the airbag 45 is deployed, the backboard 120 is bent backward at the portions extending left and right, forming an opening in the backboard 120. The airbag 45 deploys through the opening to the rear of the seat back 4.

[0113] Furthermore, in the above embodiment, the outer case 40 was provided in the recess 41, but as shown in Figure 10(A), damage to the airbag 45 during inflation may be prevented by increasing the curvature of the opening edge 130 of the recess 41. Alternatively, as shown in Figure 10(B), the outer case 40 may be fitted into the recess 41, and the airbag 45 and inflator 46 may be housed in the housing recess 40R of the outer case 40. [Explanation of Symbols]

[0114] 1: Vehicle seat 3: Seat cushion 4: Seat back 7: Seat back frame 9: Skin material 11: Side frame 12: Upper frame 28: Pillar (headrest pillar) 31: Bracket 34: Upper tongue piece 35:Lower tongue piece 36: Veranda wall 41: Recess 42: Recessed bottom wall 43: Airbag module 45: Airbag 50: Male threaded portion (fastener) 51: Through hole 55: Mounting hole 56: Blower 80: Suture site (weak area) 81: 1st Lifu 82:Second Rikifu

Claims

1. A vehicle seat equipped with a seat cushion and a seat back, The aforementioned seatback, A seat back frame including a pair of left and right side frames extending in the vertical direction and an upper frame connecting the upper ends of the left and right side frames to each other, The aforementioned seat back frame includes an airbag module supported via a bracket, The seat back frame, the bracket, and the airbag module are covered from the rear by a surface member, The surface member has a rupture portion at a position facing the airbag module, which is to open when the airbag inflates. The bracket is connected to the upper frame. The bracket has a housing portion for housing the airbag module. The airbag module includes the airbag and an inflator that introduces gas into the airbag, causing the airbag to protrude from the rear surface of the seatback and inflate it rearward and diagonally upward. At least a portion of the bracket is positioned to overlap the upper frame in the vertical direction. The aforementioned brackets are connected to the side frame at their left and right edges, respectively, for a vehicle seat.

2. The vehicle seat according to claim 1, wherein the bracket is connected to the seat back frame by an upper tongue provided on its upper edge and by a lower tongue provided on its lower part.

3. A vehicle seat equipped with a seat cushion and a seat back, The aforementioned seatback, A seat back frame including a pair of left and right side frames extending in the vertical direction and an upper frame connecting the upper ends of the left and right side frames to each other, The aforementioned seat back frame includes an airbag module supported via a bracket, The seat back frame, the bracket, and the airbag module are covered from the rear by a surface member, The surface member has a rupture portion at a position facing the airbag module, which is to open when the airbag inflates. The bracket is connected to the upper frame. The bracket has a housing portion for housing the airbag module. The airbag module includes the airbag and an inflator that introduces gas into the airbag, causing the airbag to protrude from the rear surface of the seatback and inflate it rearward and diagonally upward. At least a portion of the bracket is positioned to overlap the upper frame in the vertical direction. A vehicle seat having a deformable portion in the bracket that deforms when the airbag inflates to absorb the load.

4. The vehicle seat according to claim 3, wherein the bracket is connected to the seat back frame by an upper tongue provided on its upper edge and by a lower tongue provided on its lower part.

5. The vehicle seat according to claim 3 or claim 4, wherein the brackets are connected to the side frame at their left and right edges, respectively.

6. The vehicle seat according to any one of claims 3 to 5, wherein the bracket is bent at the deformed portion so as to protrude forward.

7. The aforementioned housing is formed by a recess that is recessed toward the front, The vehicle seat according to any one of claims 3 to 6, wherein the recess is formed by a flat bottom wall and a side wall that surrounds the bottom wall and includes a portion located below the airbag.

8. The bracket is provided with two of the deformable parts, The vehicle seat according to claim 7, wherein one of the deformed portions is located to the left of the recess, and the other of the deformed portions is located to the right of the recess.

9. A vehicle seat according to any one of claims 1 to 8, wherein a blower is provided at the same height as the airbag module.

10. A vehicle seat according to any one of claims 1 to 8, wherein a blower is provided at a position opposite to the airbag module in the front-rear direction.

11. The seat back further has a headrest provided on the upper part, A seat for a vehicle according to any one of claims 1 to 10, having a pad member supported by the seat back frame and at least a portion of which is covered by the surface member.

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