Vehicle seat

Abstract

To obtain a vehicle seat which has sufficient strength even if an upward load acts thereon from a child seat during a frontal collision or a sudden stop of a vehicle.SOLUTION: An attachment part 60A of a tether bracket 34A is welded to a lower frame 42A through a base part 62A extending to the lower side of a seat, to a vehicle outer side frame 44A through a left arm part 64A extending to the left side, and to a vehicle inner side frame 46A through a right arm part 66A extending to the right side, respectively. Thus, an upward load acts on the attachment part 60A of the tether bracket 34A from a child seat (84) through a top tether anchor (88) during a front collision or a sudden stop of a vehicle, however, the load is diffusively transmitted to a left seat back frame 30A through the base part 62A, the left arm part 64A, and the right arm part 66A. As a result, deformation of the tether bracket 34A and the left seat back frame 30A caused by the load is prevented or inhibited.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vehicle seat. [Background technology]

[0002] In recent years, the ISOFIX system for fixing child seats to vehicle seats has become popular. The ISOFIX system fixes the child seat to the vehicle seat by engaging a locking device extending rearward from the bottom of the child seat with a striker provided on the seat back of the vehicle seat.

[0003] Therefore, in the event of a frontal collision, a load is applied from the child seat to the seat back frame and the seat back panel of the vehicle seat. Various measures have been taken to prevent the seat back frame and the seat back panel from buckling due to this load.

[0004] For example, Patent Document 1 proposes a configuration in which left and right reinforcing frame brackets are welded to the left and right bottom corners of a substantially rectangular main pipe frame, thereby improving the strength of the sub-pack panel to which the striker is welded. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2011-168109 A Summary of the Invention [Problem to be solved by the invention]

[0006] Among ISOFIX type child seats, in addition to being attached to a striker, some have a top tether belt that extends from the upper part of the rear of the child seat, which is then extended from the top of the seat back of the vehicle seat to the rear side, and a metal fitting at the end of the top tether belt is engaged with a tether bracket provided on the rear side of the seat back.

[0007] This tether bracket is attached to a lower frame that constitutes the lower side of a substantially rectangular seat back frame.

[0008] Therefore, in the event of a frontal collision of the vehicle, an upward load acts on the seat back frame from the child seat through the top tether belt and the tether bracket.

[0009] There is room for improvement in terms of increasing the strength of the seat back frame against the input of this upward load.

[0010] SUMMARY OF THE PRESENT EMBODIMENT In consideration of the above, an object of the present invention is to provide a vehicle seat having sufficient strength even when an upward load from a child seat acts on a tether bracket during a frontal collision or sudden stop of the vehicle. [Means for solving the problem]

[0011] The vehicle seat according to the invention of claim 1 comprises a seatback frame including an upper frame extending in a seat width direction above the seat back, a pair of left and right side frames connected to both left and right ends of the upper frame and extending downward from the both left and right ends of the upper frame, and a lower frame extending in the seat width direction and having both ends connected to lower ends of the pair of side frames, and a first tether bracket to which an attachment tool at a tip of a top tether belt extending from a child seat is attached, the first tether bracket having a first attachment portion to which the attachment tool is attached, a first base portion extending from the first attachment portion to a seat lower side and having a lower end connected to the lower frame, a first connecting portion extending from the first attachment portion to the left side in the seat width direction and having a left end connected to the left side frame, and a second connecting portion extending from the first attachment portion to the right side in the seat width direction and having a right end connected to the right side frame. The first base portion extends directly downward from the first mounting portion. do. In addition, in the vehicle seat according to the invention described in claim 2, the first tether bracket has a first engagement portion fixed to the first mounting portion, and the first engagement portion is arranged to fit within the vertical width of the first connecting portion and the second connecting portion.

[0012] This vehicle seat has a first tether bracket disposed on the inside of a substantially rectangular seat back frame, to which a mounting tool for a top tether belt of a child seat is attached.

[0013] The first tether bracket is connected to the lower frame by a base extending downward from the first mounting portion to which the mounting fixture of the top tether belt is engaged, is connected to the left side frame by a first connecting portion extending from the first mounting portion to the left in the width direction of the seat, and is connected to the right side frame by a second connecting portion extending from the first mounting portion to the right in the width direction of the seat.

[0014] A child seat is fixed to this vehicle seat, with the top tether belt of the child seat running from the top of the seat back to the rear, and an attachment device provided at the end of the top tether belt is engaged with the first attachment portion of the first tether bracket.

[0015] In this state, if the vehicle experiences a frontal collision or comes to a sudden stop, a load acts upward on the child seat via the top tether belt to the first tether bracket.

[0016] The seat back has a roughly rectangular frame that runs from the first mounting portion of the first tether bracket through the base, the lower frame, the left side frame, and the first connecting portion of the first tether bracket before returning to the first mounting portion.

[0017] The seat back also has a roughly rectangular frame that runs from the first mounting portion of the first tether bracket through the base, the lower frame, the right side frame, and the second connecting portion of the first tether bracket, and then returns to the first mounting portion.

[0018] In this way, the upward load acting on the first mounting portion of the first tether bracket is received by the approximately rectangular seatback frame and a pair of approximately rectangular frame bodies on the left and right formed by part of the seatback frame and part of the first tether bracket, i.e., three approximately rectangular frame bodies, thereby preventing or suppressing deformation of the first tether bracket and the seatback frame.

[0019] In other words, the upward load input to the first mounting portion of the first tether bracket is distributed and transmitted from the base of the first tether bracket to the lower frame, from the first connecting portion to the left side frame, and from the second connecting portion to the right side frame, thereby preventing or suppressing deformation of the first tether bracket and the seatback frame.

[0020] Claim 3 The vehicle seat described includes a seatback frame including an upper frame extending in the seat width direction above the seat back, a pair of left and right side frames connected to both left and right ends of the upper frame and extending downward from the left and right ends of the upper frame, respectively, and a lower frame extending in the seat width direction and having both ends connected to lower ends of the pair of side frames, respectively; a reinforcement extending in the seat vertical direction and connecting a middle position of the upper frame and a middle position of the lower frame; and a second tether belt disposed inside the seatback frame to the left or right of the reinforcement and to which a mounting tool of a tip of a top tether belt extending from a child seat is attached. the second tether bracket has a second mounting portion to which the mounting fixture is engaged, a second base portion extending from the second mounting portion toward the seat lower side and having a lower end connected to the lower frame, a third connecting portion extending from the second mounting portion to the left in the seat width direction and having a left end connected to the left side frame or the reinforcement, and a fourth connecting portion extending from the second mounting portion to the right in the seat width direction and having a right end connected to the reinforcement or the right side frame. In addition, in the vehicle seat according to the invention described in claim 4, the second tether bracket has a second engagement portion fixed to the second mounting portion, and the second engagement portion is arranged to fit within the vertical width of the third connecting portion and the fourth connecting portion.

[0021] This vehicle seat has a reinforcement that connects a middle position of an upper frame of a seat back frame and a middle position of a lower frame and extends in the up-down direction of the seat.

[0022] In addition, in this vehicle seat, a second tether bracket to which a mounting tool for a top tether belt of a child seat is attached is disposed on the left or right side of the reinforcement inside the substantially rectangular seat back frame.

[0023] The second tether bracket is connected to the lower frame by a base extending downward from the second mounting portion to which the mounting fixture is engaged, connected to the left side frame or reinforcement by a third connecting portion extending from the second mounting portion to the left in the seat width direction, and connected to the reinforcement or right side frame by a fourth connecting portion extending from the second mounting portion to the right in the seat width direction.

[0024] A child seat is fixed to this vehicle seat, with the top tether belt of the child seat running from the top of the seat back to the rear, and an attachment device provided at the end of the top tether belt is engaged with the second attachment portion of the second tether bracket.

[0025] In this state, if the vehicle experiences a frontal collision or comes to a sudden stop, a load will act upward on the child seat via the top tether belt to the second tether bracket.

[0026] The seat back has a roughly rectangular frame that extends from the second mounting portion of the second tether bracket through the second base, the lower frame, the left side frame or reinforcement, and the third connecting portion of the second tether bracket, and then returns to the second mounting portion.

[0027] The seat back also has a generally rectangular frame that extends from the second mounting portion of the second tether bracket through the second base, the lower frame, the reinforcement or the right side frame, and the fourth connection portion of the second tether bracket, and then returns to the second mounting portion.

[0028] Furthermore, the seat back has a rectangular frame body formed therein that is made up of a part of the seat back frame (a part of the upper frame, the left or right side frame, a part of the lower frame) and a reinforcement.

[0029] In this way, the upward load acting on the second mounting portion of the second tether bracket is received by a frame body formed by a part of the approximately rectangular seatback frame and the reinforcement, and a pair of approximately rectangular frame bodies on the left and right formed by a part of the seatback frame and a part of the second tether bracket, i.e., three approximately rectangular frame bodies, thereby preventing or suppressing deformation of the second tether bracket and the seatback frame.

[0030] In other words, the upward load input to the second mounting portion of the second tether bracket is distributed and transmitted from the second base portion of the second tether bracket to the lower frame, from the third connecting portion to the left side frame or reinforcement, and from the fourth connecting portion to the reinforcement or right side frame, thereby preventing or suppressing deformation of the second tether bracket and the seatback frame.

[0031] Claim 5 The vehicle seat according to the present invention is 3The vehicle seat described further includes a third tether bracket that is arranged on the opposite side of the second tether bracket across the reinforcement inside the seatback frame and to which an attachment device at an end of a top tether belt extending from a child seat is engaged, and the third tether bracket has a third attachment portion to which the attachment device is engaged, a third base portion extending from the third attachment portion to a lower side of the seat and having a lower end connected to the lower frame, a fifth connecting portion extending from the third attachment portion to the left side in the seat width direction and having a left end connected to the reinforcement or the left side frame, and a sixth connecting portion extending from the third attachment portion to the right side in the seat width direction and having a right end connected to the right side frame or the reinforcement.

[0032] This vehicle seat has a reinforcement that connects a middle position of an upper frame of a seat back frame and a middle position of a lower frame and extends in the up-down direction of the seat.

[0033] In addition, in this vehicle seat, a third tether bracket, to which a mounting device for a top tether belt of a child seat is attached, is disposed on the opposite side of the second tether bracket, across the reinforcement, inside the approximately rectangular seat back frame.

[0034] The third tether bracket is connected to the lower frame by a base extending downward from the third mounting portion to which the mounting fixture is engaged, connected to the reinforcement or the left side frame by a fifth connecting portion extending from the third mounting portion to the left in the width direction of the seat, and connected to the right side frame or reinforcement by a sixth connecting portion extending from the third mounting portion to the right in the width direction of the seat.

[0035] A child seat is fixed to this vehicle seat, with the top tether belt of the child seat running from the top of the seat back to the rear, and an attachment device provided at the end of the top tether belt is engaged with the third attachment portion of the third tether bracket.

[0036] In this state, if the vehicle experiences a frontal collision or comes to a sudden stop, a load will act upward on the child seat via the top tether belt to the third tether bracket.

[0037] The seat back has a roughly rectangular frame that extends from the third mounting portion of the third tether bracket through the third base, the lower frame, the reinforcement or the left side frame, and the fifth connecting portion of the third tether bracket, and then returns to the third mounting portion.

[0038] The seat back also has a roughly rectangular frame that extends from the third mounting portion of the third tether bracket through the third base, the lower frame, the right side frame or reinforcement, and the sixth connection portion of the third tether bracket, and then returns to the third mounting portion.

[0039] Furthermore, the seatback frame has a rectangular frame body formed therein that is made up of a part of the seatback frame (a part of the upper frame, the right or left side frame, and a part of the lower frame) and a reinforcement.

[0040] In this way, the upward load acting on the third mounting portion of the third tether bracket is received by a frame body formed by a part of the approximately rectangular seatback frame and the reinforcement, and a pair of approximately rectangular frame bodies on the left and right formed by a part of the seatback frame and a part of the third tether bracket, i.e., three approximately rectangular frame bodies, thereby preventing or suppressing deformation of the third tether bracket and the seatback frame.

[0041] In other words, the upward load input to the third mounting portion of the third tether bracket is distributed and transmitted from the third base portion of the third tether bracket to the lower frame, from the fifth connecting portion to the reinforcement or the left side frame, and from the sixth connecting portion to the right side frame or reinforcement, thereby preventing or suppressing deformation of the third tether bracket and the seat back frame.

[0042] Claim6 The vehicle seat described in claim 1 is a vehicle seat in which at least one of the connecting portions is connected to the side frame via a weld bead, and the weld bead is formed over the entire widthwise area of ​​the connecting portion.

[0043] In this vehicle seat, at least one of the connecting parts and the side frame are welded with a weld bead formed over the entire width of the connecting part, so that the load is efficiently transferred from the connecting part of the tether bracket to the side frame during a frontal collision or sudden stop of the vehicle, and deformation of the tether bracket and the seat back frame is further prevented or suppressed.

[0044] Claim 7 The vehicle seat according to the present invention is 6 In the vehicle seat described above, all of the connecting portions are connected to the side frames via weld beads, and the weld beads are formed across the entire widthwise area of ​​the connecting portions.

[0045] In this vehicle seat, all of the connecting parts and the side frames are welded with weld beads formed over the entire width of the connecting parts, so that the load is efficiently transferred from the connecting parts of the tether brackets to the side frames in the event of a frontal collision or sudden stop of the vehicle, and deformation of the tether brackets and the seat back frame is further prevented or suppressed.

[0046] Here, "all connecting portions" means the first connecting portion and the second connecting portion.

[0047] Claim 8 The vehicle seat according to the present invention is 3 or 5 In the described vehicle seat, at least one of the connecting portions is connected to the side frame or the reinforcement via a weld bead, and the weld bead is formed across the entire widthwise area of ​​the connecting portion.

[0048] In this vehicle seat, at least one connecting portion and the side frame or the reinforcement are welded with a weld bead formed over the entire widthwise area of ​​the connecting portion, so that load is efficiently transferred from the connecting portion of the tether bracket to the side frame or the reinforcement during a frontal collision or sudden stop of the vehicle, and deformation of the tether bracket or the seat back frame is further prevented or suppressed.

[0049] Claim 9 The vehicle seat according to the present invention is 8 In the described vehicle seat, all of the connecting portions are connected to the side frames or the reinforcements via weld beads, and the weld beads are formed across the entire widthwise area of ​​the connecting portions.

[0050] In this vehicle seat, all of the connecting parts and the side frames or the reinforcements are welded with weld beads formed over the entire widthwise area of ​​the connecting parts, so that in the event of a frontal collision or sudden stop of the vehicle, the load is efficiently transferred from the connecting parts of the tether brackets to the side frames or the reinforcements, and deformation of the tether brackets and the seat back frame is further prevented or suppressed.

[0051] In addition, here, "all of the connecting portions" means the third connecting portion and the fourth connecting portion in the vehicle seat according to claim 2, and the third connecting portion to the sixth connecting portion in the vehicle seat according to claim 3.

[0052] Claim 10 The vehicle seat described herein comprises: 6 , 7 In the vehicle seat according to any one of claims 1 to 5, at least one of the connecting portions overlaps with a ridge line of the side frame in a front view of the seat.

[0053] In this vehicle seat, at least one of the connecting portions overlaps with the side frame when viewed from the front of the seat, so that the load transmitted from the connecting portion of the tether bracket to the side frame during a frontal collision or sudden stop of the vehicle is efficiently transmitted to the upper frame and the lower frame via the ridge line of the side frame, further preventing or suppressing deformation of the tether bracket and the seat back frame.

[0054] Claim 11 The vehicle seat according to the present invention is 3 , 5 , 8 , 9 In the vehicle seat according to any one of claims 1 to 5, at least one of the connecting portions overlaps with a ridge line of the side frame or the reinforcement in a front view of the seat.

[0055] In this vehicle seat, at least one of the connecting portions overlaps with the side frame or the reinforcement in a front view of the seat. Therefore, a load transmitted from the connecting portion of the tether bracket to the side frame or the reinforcement during a frontal collision or sudden stop of the vehicle is efficiently transmitted to the upper frame or the lower frame via the ridge line of the side frame or the reinforcement, further preventing or suppressing deformation of the tether bracket or the seat back frame.

[0056] Claim 12 The vehicle seat described in claim 1 and claim 5 The vehicle seats described above are arranged side by side to form one vehicle seat.

[0057] This vehicle seat has three seats, each of which is equipped with a tether bracket to which a mounting device for a top tether belt of a child seat can be attached. Therefore, a child seat can be fixed in any of the three positions (three seats) of the vehicle seat, and deformation of any of the tether brackets and seat back frames (including reinforcements) can be prevented or suppressed in the event of a frontal collision or sudden stop of the vehicle. Effect of the Invention

[0058] As described above, in a vehicle seat, the tether bracket and seat back frame have sufficient strength to prevent or suppress deformation of the tether bracket and seat back frame even when an upward load is applied from the child seat during a frontal collision or sudden stop of the vehicle. [Brief description of the drawings]

[0059] [Figure 1] 1 is a front view showing a schematic configuration of a seat back of a vehicle seat according to an embodiment of the present invention; [Diagram 2] 1 is a side view showing a schematic diagram of a state in which a child seat is installed in a vehicle seat according to an embodiment; [Diagram 3] FIG. 2 is a front view of a left seat back according to an embodiment. [Figure 4] FIG. 2 is a diagram showing a portion of a left seat back according to an embodiment as viewed from the rear side. [Diagram 5] 5A to 5C are diagrams illustrating the operation of a seat back according to one embodiment. [Figure 6] FIG. 4 is a front view showing a schematic configuration of a seat back of a vehicle seat according to a comparative example. [Figure 7] FIG. 13 is a front view of a left seat back according to a comparative example. [Figure 8] 11A and 11B are diagrams illustrating the operation of a seat back according to a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0060] Hereinafter, a rear seat 10 as a vehicle seat according to an embodiment of the present invention will be described with reference to the drawings. Note that the arrows FR, RH, and UP shown in each drawing indicate the front, right, and up directions of the rear seat 10, respectively. In addition, in this embodiment, the front-rear, left-right, top-bottom directions of the rear seat 10 match the front-rear, left-right, top-bottom directions of the vehicle (automobile) in which the rear seat 10 is mounted. Hereinafter, when the front-rear, left-right, top-bottom directions are simply used for the description, they refer to the front-rear direction of the seat, the left-right direction of the seat (seat width direction), and the top-bottom direction of the seat. Furthermore, the blackened parts in each drawing indicate welded parts (weld beads).

[0061] <Vehicle seat configuration>

[0062] First, the configuration of a rear seat to which the vehicle seat according to this embodiment is applied will be described.

[0063] Fig. 1 shows a front view of a seat back frame showing the framework of the seat back of a rear seat 10. As shown in Fig. 1, in this embodiment, the rear seat 10 is, for example, a second- or third-row seat and is a three-seater seat. The rear seat 10 is broadly divided into a left rear seat 12 provided on the left side and a right rear seat 14 provided on the right side.

[0064] The rear seat 10 corresponds to the "vehicle seat."

[0065] 2, the left rear seat 12 is equipped with a left seat cushion 16 that supports the thighs and waist of the seated occupant, and a left seat back 18 that is provided on the rear end side of the left seat cushion 16 and supports the upper body of the seated occupant. Similarly to the left rear seat 12, the right rear seat 14 is equipped with a right seat cushion 20 that supports the thighs and waist of the seated occupant, and a right seat back 22 that is provided on the rear end side of the right seat cushion 20 and supports the upper body of the seated occupant.

[0066] 1, the left seat back 18 and the right seat back 22 are provided adjacent to each other in the left-right direction of the seat (vehicle width direction) and are rotatable independently of each other about an axis along the seat width direction. In this embodiment, the dimensional ratio of the left seat back 18 and the right seat back 22 in the vehicle width direction is set to, for example, 40:60.

[0067] A left headrest 24 is connected to the upper end of the left seat back 18 so as to be able to rise and fall. A right headrest 26 is connected to the upper right end of the right seat back 22 so as to be able to rise and fall, and a center headrest 28 disposed between the right headrest 26 and the left headrest 24 is connected to the upper left end of the right seat back 22 so as to be able to rise and fall.

[0068] (Left seat back)

[0069] Next, the configuration of the left seat back 18 will be described.

[0070] As shown in FIG. 1, the left side seatback 18 includes a left side seatback frame 30A which forms an approximately rectangular frame body constituting the outer edge of the left side seatback 18, a plate-shaped left side seatback panel 32A attached to the back surface of the left side seatback frame 30A, and a tether bracket 34A attached to the left side seatback frame 30A.

[0071] It should be noted that the tether bracket 34A corresponds to the "first tether bracket."

[0072] The left seat back panel 32A is formed, for example, by pressing a metal plate, and is attached to the back surface of the left seat back frame 30A by means of welding or the like.

[0073] (Seat back frame)

[0074] In this embodiment, the left seatback frame 30A is configured to include an upper frame (upper skeletal member) 40A, a lower frame (lower skeletal member) 42A, a vehicle outer side frame (outer skeletal member) 44A, and a vehicle inner side frame (hinge skeletal member) 46A.

[0075] The vehicle outer side frame 44A corresponds to the "left side frame", and the vehicle inner side frame 46A corresponds to the "right side frame".

[0076] The upper frame 40A is provided along the seat width direction at the upper end of the left seatback frame 30A, and has attached thereto a pair of retaining members 48A that retain the left headrest 24 that supports the head of a seated occupant.

[0077] The lower frame 42A is provided along the seat width direction at the lower end of the left seatback frame 30A, and a reclining hinge portion 50A that rotates the left seatback 18 relative to the left seat cushion 16 is attached to the lower frame 42A.

[0078] The vehicle outer side frame 44A is provided along the seat height direction on the outer side of the left seatback frame 30A in the vehicle width direction, and a locking bracket (not shown) for fixing it to the vehicle body is attached to the upper end side.

[0079] The vehicle inner side frame 46A is provided along the seat height direction on the inner side in the vehicle width direction of the left seatback frame 30A, and has a center hinge portion 52A that allows the left seatback 18 to recline.

[0080] In this embodiment, the upper frame 40A, the lower frame 42A, the vehicle outer side frame 44A, and the vehicle inner side frame 46A each use a pipe having a hollow structure (rectangular cross-section) made of a metal material such as iron or aluminum.

[0081] In addition, the upper frame 40A, the lower frame 42A, the vehicle outer side frame 44A, and the vehicle inner side frame 46A are integrated together by welding their ends.

[0082] (Tether bracket)

[0083] 1 and 3, the tether bracket 34A is disposed inside the left seatback frame 30A. The tether bracket 34A is integrally formed from a metal plate and has an attachment portion 60A, a base portion 62A extending from the attachment portion 60A below the seat, a left arm portion 64A extending leftward from the attachment portion 60A, and a right arm portion 66A extending rightward from the attachment portion 60A.

[0084] The mounting portion 60A corresponds to the "first mounting portion", the base portion 62A corresponds to the "first base portion", the left arm portion 64A corresponds to the "first connecting portion", and the right arm portion 66A corresponds to the "second connecting portion".

[0085] As shown in FIG. 3, the mounting portion 60A has a generally rectangular frame shape having an upper portion 70A extending in the seat width direction, a lower portion 72A, a left side portion 74A extending in the seat top-bottom direction, and a right side portion 76A, and has a rectangular hole portion 78A formed in the center.

[0086] In addition, both ends of a U-shaped locking portion 80A are welded to the seat front side of the left side portion 74A and the seat front side of the right side portion 76A of the mounting portion 60A. Therefore, the horizontal bar portion 82A extending in the seat width direction of the locking portion 80A is positioned above the hole portion 78A of the mounting portion 60A.

[0087] As shown in Fig. 3, the base 62A extends from the lower portion 72A of the mounting portion 60A below the seat, and its lower end is inserted between the lower frame 42A and the left seat back panel 32A and welded to the seat rear side of the lower frame 42A (see Fig. 4). That is, as shown in Fig. 4, the lower end of the base 62A is welded to the lower frame 42A by a welded portion (weld bead) 63A formed by arc welding. Also, the welded portion (weld bead) 63A is formed over the entire region in the width direction (seat width direction) of the base 62A.

[0088] As shown in Fig. 3, the left arm portion 64A extends to the left in the seat width direction from below the left side portion 74A of the mounting portion 60A, and has a left end welded to the seat front side of the vehicle-outside side frame 44A. That is, as shown in Fig. 3, the left end of the left arm portion 64A is welded to the vehicle-outside side frame 44A by a weld portion (weld bead) 65A formed by arc welding. Moreover, the weld portion (weld bead) 65A is formed over the entire region of the left arm portion 64A in the width direction (seat up-down direction).

[0089] In this manner, by welding the left arm portion 64A to the vehicle outer side frame 44A, the ridge line 45A of the vehicle outer side frame 44A, which is a hollow structure with a rectangular cross section, overlaps with the left arm portion 64A when viewed from the front of the seat.

[0090] As shown in Fig. 3, the right arm portion 66A extends from below the right side portion 76A of the mounting portion 60A to the right in the seat width direction, and has a right end welded to the seat front side of the vehicle inner side frame 46A. That is, as shown in Fig. 3, the right end of the right arm portion 66A is welded to the vehicle inner side frame 46A by a weld portion (weld bead) 67A formed by arc welding. The weld portion (weld bead) 67A is formed over the entire area of ​​the right arm portion 66A in the width direction (seat up-down direction).

[0091] By welding the right arm portion 66A to the vehicle interior side frame 46A in this manner, the right arm portion 66A overlaps with the ridge line 47A of the vehicle interior side frame 46A, which is a hollow structure with a rectangular cross section, when viewed from the front of the seat.

[0092] 4, a hole 90A corresponding to the hole 78A of the mounting portion 60A is formed in the left seat back panel 32A. Therefore, the horizontal bar portion 82A of the locking portion 80A is exposed to the rear of the seat back through the hole 78A of the mounting portion 60A and the hole 90A of the left seat back panel 32A.

[0093] As shown in FIG. 2, the tether bracket 34A configured in this manner has a top tether anchor 88 attached to the end of a top tether belt 86 of a child seat 84 disposed on the left rear seat 12, which is engaged with a locking portion 80A (horizontal bar portion 82A) provided on an attachment portion 60A provided on the left seat back 18.

[0094] The top tether anchor 88 corresponds to the "attachment."

[0095] (Right side seat back)

[0096] The right seat back 22 is substantially similar to the left seat back 18, so the same components are designated by the same reference numerals with the letter B or C, and detailed description thereof will be omitted. The components different from the left seat back 18 will be briefly described.

[0097] The right seatback frame 30B of the right seatback 22 further has a reinforcement 92 that connects an intermediate portion of the upper frame 40B and an intermediate portion of the lower frame 42B. The reinforcement 92 has an upper end welded to the seat front side of the upper frame 40B, and a lower end welded to the seat front side of the lower frame 42B.

[0098] That is, in the right seatback frame 30B, a reinforcement 92 is disposed between the vehicle outer side frame 44B and the vehicle inner side frame 46B. The reinforcement 92 is a pipe made of a metal material such as iron or aluminum and having a hollow structure (square cross section).

[0099] Further, a left tether bracket 34B is disposed between the vehicle outer side frame 44B and the reinforcement 92. On the other hand, a right tether bracket 34C is disposed between the vehicle inner side frame 46B and the reinforcement 92.

[0100] The vehicle outer side frame 44B corresponds to the "right side frame", and the vehicle inner side frame 46B corresponds to the "left side frame".

[0101] Furthermore, the left tether bracket 34B and the right tether bracket 34C correspond to the "second tether bracket" and the "third tether bracket", respectively.

[0102] Furthermore, the mounting portion 60B of the left tether bracket 34B corresponds to the "second mounting portion" or the "third mounting portion," the base portion 62B corresponds to the "second base portion" or the "third base portion," the left arm portion 64B corresponds to the "third connecting portion" or the "fifth connecting portion," and the right arm portion 66B corresponds to the "fourth connecting portion" or the "sixth connecting portion."

[0103] On the other hand, the mounting portion 60C of the right side tether bracket 34C corresponds to the "third mounting portion" or the "second mounting portion," the base portion 62C corresponds to the "third base portion" or the "second base portion," the left side arm portion 64C corresponds to the "fifth connecting portion" or the "third connecting portion," and the right side arm portion 66C corresponds to the "sixth connecting portion" or the "fourth connecting portion."

[0104] The left tether bracket 34B has a configuration substantially similar to that of the tether bracket 34A, but differs in that an end of the right arm portion 66B is welded to a reinforcement 92.

[0105] The right tether bracket 34C has a configuration substantially similar to that of the tether bracket 34A, but differs in that an end of the left arm portion 64C is welded to a reinforcement 92.

[0106] <Explanation of Comparative Example>

[0107] Next, a rear seat 110 according to a comparative example will be described to explain the function of the rear seat 10 according to this embodiment. Note that the same components as those in the rear seat 10 are given the same reference numerals plus 100, and detailed explanations thereof will be omitted. The only difference between the rear seat 110 and the rear seat 10 is the configuration of the tether bracket, and only that part will be described.

[0108] 6 and 7, the tether bracket 134A of the left seat back 118 of the left rear seat 112 has only a base 162A extending from the attachment portion 160A toward the seat bottom. In other words, the tether bracket 134A is connected to the left seat back frame 130A (lower frame 142A) only via the base 162A.

[0109] Similarly, as shown in FIG. 6, the left tether bracket 134B and the right tether bracket 134C of the right seat back 122 of the right rear seat 114 have mounting portions 160B, 160B connected to the lower frame 142B only via base portions 162B, 162C, respectively.

[0110] <Functions and Effects of Vehicle Seats>

[0111] Next, the operation and effect of the rear seat 10 to which the vehicle seat according to this embodiment is applied will be described.

[0112] (Premise)

[0113] A case will be described where a child seat 84 is attached to the left rear seat 12 of the rear seat 10. In this case, as shown in Fig. 2, the child seat 84 has a locking device (not shown) attached to a striker provided on the left seat back 18, and a top tether belt 86 extends to the rear back side of the left seat back 18, and a top tether anchor 88 provided at the tip of the top tether belt 86 is attached (locked) to a horizontal bar portion 82A disposed in the mounting portion 60A through a hole portion 90A in the left seat back panel 32A and a hole portion 78A in the tether bracket 34A.

[0114] In this state, if the vehicle suddenly stops or a frontal collision occurs, a large inertial load is input from the child seat 84 to the left seat back 18. Part of this inertial load is input as an upward load to the tether bracket 34A via the top tether belt 86 (see arrow F in FIG. 5).

[0115] (Comparative Example)

[0116] In the rear seat 110 of the comparative example, part of the inertial load of the child seat 84 acts on the tether bracket 134A of the left seat back 118 as an upward load F via the top tether belt 86, as shown in FIG.

[0117] This load F acts on the lower frame 142A from the mounting portion 160A of the tether bracket 134A via the base portion 162A.

[0118] Here, the left seatback frame 130A is simply formed with a roughly rectangular frame body (see dashed line portion δ1 in FIG. 8), and if an upward load is input to the tether bracket 134A, there is a risk that the welded portion between the tether bracket 134A and the left seatback frame 130A (lower frame 142A) will be destroyed, or that the tether bracket 134A or the left seatback frame 130A will be deformed.

[0119] Similarly, in the right seatback frame 130B, a substantially rectangular frame body (Figure 8, dashed line portion δ2) is formed for the left tether bracket 134B from the upper frame 140B, the reinforcement 192, the lower frame 142B, and the vehicle outer side frame 144B, while a substantially rectangular frame body (Figure 8, dashed line portion δ3) is formed for the right tether bracket 134C from the upper frame 140B, the reinforcement 192, the lower frame 142B, and the vehicle inner side frame 146B.

[0120] However, as with the left seatback frame 130A, if an upward load is input from the child seat 84 to the left tether bracket 134B or the right tether bracket 134C during a frontal collision or sudden stop of the vehicle, there is a risk that the left tether bracket 134B, the right tether bracket 134C, or the right seatback frame 130B (including the reinforcement 192) will deform.

[0121] (In this embodiment)

[0122] In the left rear seat 12 (left seat back 18) of this embodiment, the mounting portion 60A of the tether bracket 34A is connected (welded) to the lower frame 42A via the base 62A, and is also connected (welded) to the vehicle outer side frame 44A via the left arm portion 64A and to the vehicle inner side frame 46A via the right arm portion 66A.

[0123] Therefore, as shown in FIG. 5, in the left seat back 18, inside the left seat back frame 30A (see dashed line portion α1 in FIG. 5), which is a substantially rectangular frame body, there are formed: a substantially rectangular frame body (see dashed line portion β1 in FIG. 5) consisting of the base 62A, mounting portion 60A, left arm portion 64A, vehicle outer side frame 44A, and lower frame 42A of the tether bracket 34A; and a substantially rectangular frame body (see dashed line portion γ1 in FIG. 5) consisting of the base 62A, mounting portion 60A, right arm portion 66A, vehicle inner side frame 46A, and lower frame 42A of the tether bracket 34A.

[0124] In other words, even if an upward load F acts on the tether bracket 34A from the child seat 84 via the top tether belt 86 during a sudden stop of the vehicle or a frontal collision, the load acting on the mounting portion 60A is received by three rectangular frame bodies (see Figure 5, dashed line portion α1, dotted line portion β1, γ1), thereby preventing or suppressing deformation of the left seatback frame 30A and the tether bracket 34A.

[0125] In other words, the upward load F acting on the mounting portion 60A of the tether bracket 34A is dispersed and transmitted from the base 62A of the tether bracket 34A to the lower frame 42A, from the left arm portion 64A to the vehicle outer side frame 44A, and from the right arm portion 66A to the vehicle inner side frame 46A. In other words, the load F acting on the mounting portion 60A from the top tether belt 86 is transmitted to the left seatback frame 30A via three load transmission paths, thereby making it possible to prevent or suppress deformation of the left seatback frame 30A and the tether bracket 34A.

[0126] In particular, if the only goal was to improve the strength of the left seatback frame 30A, this could be achieved by making each tube-shaped frame thicker; however, it is sufficient to simply add and weld the left arm portion 64A and the right arm portion 66A to the left tether bracket 34B, which is formed from a metal plate, and thereby suppress the increase in mass while improving the strength (suppressing deformation).

[0127] In addition, the base 62A and the lower frame 42A are welded together at a welded portion (weld bead) 63A formed over the entire widthwise area of ​​the base 62A. The left arm portion 64A and the vehicle-outside side frame 44A are welded together at a welded portion (weld bead) 65A formed over the entire widthwise area of ​​the left arm portion 64A. Similarly, the right arm portion 66A and the vehicle-inside side frame 46A are welded together at a welded portion (weld bead) 67A formed over the entire widthwise area of ​​the right arm portion 66A. Therefore, load transmission from the base 62A to the lower frame 42A, from the left arm portion 64A to the vehicle-outside side frame 44A, and from the right arm portion 66A to the vehicle-inside side frame 46A is efficiently performed, and deformation of the tether bracket 34A and the seat back frame 30A during a frontal collision or sudden stop of the vehicle is further prevented or suppressed.

[0128] Furthermore, in a front view of the seat, the left arm portion 64A (its left end portion) overlaps the ridge line 45A of the vehicle outer side frame 44A, and the right arm portion 66A (its right end portion) overlaps the ridge line 47A of the vehicle inner side frame 46A. Therefore, in the event of a frontal collision or sudden stop of the vehicle, the load transmitted from the left arm portion 64A and the right arm portion 66A of the tether bracket 34A to the vehicle outer side frame 44A and the vehicle inner side frame 46A is efficiently transmitted to the upper frame 40A and the lower frame 42A via the ridge lines 45A and 47A, respectively, and deformation of the tether bracket 34A and the seatback frame 30A is further prevented or suppressed.

[0129] Similarly, as shown in FIG. 1, in the right seat back 22, a substantially rectangular frame body (see FIG. 5, dashed line portion β2) consisting of the mounting portion 60B of the left tether bracket 34B, the left arm portion 64B, the vehicle inner side frame 46B, the lower frame 42B, and the base portion 62B of the left tether bracket 34B is formed inside a rectangular frame body (see FIG. 5, dashed line portion α2) consisting of the upper frame 40B, the vehicle inner side frame 46B, the lower frame 42B, and the reinforcement 92, and a substantially rectangular frame body (see FIG. 5, dashed line portion γ2) consisting of the mounting portion 60B of the left tether bracket 34B, the right arm portion 66B, the reinforcement 92, the lower frame 42B, and the base 62B of the left tether bracket 34B is formed inside the rectangular frame body (see FIG. 5, dashed line portion α2).

[0130] As shown in FIG. 1, for the right tether bracket 34C, a substantially rectangular frame body (see FIG. 5, dashed line portion α3) consisting of the upper frame 40B, the vehicle outer side frame 44B, the lower frame 42B, and the reinforcement 92 is formed inside the substantially rectangular frame body (see FIG. 5, dashed line portion α3) consisting of the mounting portion 60C of the right tether bracket 34C, the left arm portion 64C, the reinforcement 92, the lower frame 42B, and the base portion 62C of the right tether bracket 34C, and a substantially rectangular frame body (see FIG. 5, dashed line portion γ3) consisting of the mounting portion 60C of the right tether bracket 34C, the right arm portion 66C, the vehicle outer side frame 44B, the lower frame 42B, and the base portion 62C of the right tether bracket 34C.

[0131] Therefore, the upward load on the left side tether bracket 34B or the right side tether bracket 34C is received by three frame bodies (see Figure 5, dashed line portion α2, dotted line portion β2, γ2), (see Figure 5, dashed line portion α3, dotted line portion β3, γ3), respectively, so that deformation of the right side seatback frame 30B (including reinforcement 92) and the left side tether bracket 34B or the right side tether bracket 34C can be prevented or suppressed.

[0132] In other words, the upward load F acting on the mounting portion 60B of the left tether bracket 34B is distributed from the base 62B, the left arm portion 64B, and the right arm portion 66B and transmitted to the frame body consisting of the right seatback frame 30B and the reinforcement 92 (see dashed line portion α2 in Figure 5), thereby preventing or suppressing deformation of the right seatback frame 30B and the left tether bracket 34B.

[0133] Similarly, the upward load F acting on the mounting portion 60C of the right side tether bracket 34C is distributed from the base 62C, the left side arm portion 64C, and the right side arm portion 66C and transmitted to the frame body consisting of the right side seatback frame 30B and the reinforcement 92 (see dashed line portion α3 in Figure 5), thereby preventing or suppressing deformation of the right side seatback frame 30B and the right side tether bracket 34C.

[0134] Furthermore, if it were only necessary to improve the strength of the right side seatback frame 30B and the reinforcement 92, this could be achieved by making each frame, which is tubular, thicker; however, it is sufficient to simply add and weld the left arm portions 64B, 64C and the right arm portions 66B, 66C to the left tether bracket 34B and the right tether bracket 34C, which are formed from metal plates, thereby making it possible to suppress mass increase while improving strength (suppressing deformation).

[0135] In addition, the base 62B of the left tether bracket 34B and the lower frame 42B are welded at a welded portion (weld bead) 63B (not shown) formed over the entire widthwise area of ​​the base 62B. The left arm portion 64B and the vehicle inner side frame 46B are welded at a welded portion (weld bead) 65B formed over the entire widthwise area of ​​the left arm portion 64B. Similarly, the right arm portion 66B and the reinforcement 92 are welded at a welded portion (weld bead) 67B formed over the entire widthwise area of ​​the right arm portion 66B. Therefore, the load is efficiently transmitted from the base 62B to the lower frame 42B, from the left arm portion 64B to the vehicle inner side frame 46B, and from the right arm portion 66B to the reinforcement 92, and deformation of the left tether bracket 34B and the right seat back frame 30B (including the reinforcement 92) is further prevented or suppressed during a frontal collision or sudden stop of the vehicle.

[0136] The welded portions (weld beads) 63C (not shown), 65C, 67C between the right tether bracket 34C and the right seatback frame 30B (including the reinforcement 92) also provide the same effects.

[0137] Furthermore, in a front view of the seat, the left arm portion 64B overlaps the ridge line 47B of the vehicle inner side frame 46B, and the right arm portion 66A overlaps the ridge line 93B of the reinforcement 92. Therefore, in the event of a frontal collision or sudden stop of the vehicle, the load transmitted from the left arm portion 64B and the right arm portion 66B of the left tether bracket 34B to the vehicle inner side frame 46B and the reinforcement 92 is efficiently transmitted to the upper frame 40B and the lower frame 42B via the ridge lines 47B and 93B, respectively, further preventing or suppressing deformation of the left tether bracket 34B and the right seatback frame 30B.

[0138] The same effect is achieved by the relationship between the right tether bracket 34C and the ridge line 93C of the reinforcement 92, and the ridge line 45B of the vehicle outer side frame 44B.

[0139] (others)

[0140] In this embodiment, the lower end of the base 62A of the tether bracket 34A is inserted between the lower frame 42A and the left seat back panel 32A and welded to the seat rear side of the lower frame 42A, and the left arm portion 64A and the right arm portion 66A are welded to the seat front sides of the vehicle outer side frame 44A and the vehicle inner side frame 46A, respectively, but the welding positions are not particularly limited. For example, the base 62A of the tether bracket 34A may be welded to the seat front side of the lower frame 42A. The same applies to the left tether bracket 34B and the right tether bracket 34C.

[0141] In this embodiment, the tether bracket 34A is provided on the left seat back 18 of the rear seat 10, and the left tether bracket 34B and the right tether bracket 34C are provided on the right seat back 22, but any one or any two may be used.

[0142] Furthermore, although the present invention has been described with reference to rear seat 10 having three seats as a vehicle seat, it is also possible to apply the present invention to a vehicle seat having one seat, such as left rear seat 12, or to a vehicle seat having two seats, such as right rear seat 14.

[0143] In this embodiment, the welded portions (weld beads) 65A to 65C and 67A to 67C are formed across the entire widthwise area of ​​the left arm portions 64A to 64C and the right arm portions 66A to 66C, but this is not limiting.

[0144] Furthermore, in this embodiment, the upper frames 40A, 40B, the lower frames 42A, 42B, the vehicle outer side frames 44A, 44B, and the vehicle inner side frames 46A, 46B of the left seat back 18 and the right seat back 22, and the reinforcement 92 of the right seat back 22 are pipes formed of a metal material such as iron or aluminum and having a hollow structure (square cross section), but this is not limited to this. In other words, any material may be used as long as it can ensure the strength and structure required for the seat back frame. For example, each of the above members may be a hollow structure (circular cross section) or a solid structure.

[0145] In addition, the present invention can be practiced with various modifications without departing from the spirit and scope of the present invention. Furthermore, the scope of the present invention is not limited to the above-described embodiments. [Explanation of symbols]

[0146] 10 Rear seat (vehicle seat) 18 Left seat back (seat back) 22 Right seat back (seat back) 30A Left seat back frame (seat back frame) 30B Right side seat back frame (seat back frame) 40A, 40B Upper frame 42A, 42B Lower frame 44A Vehicle outer side frame (left side frame) 44B Vehicle outer side frame (right side frame) 45A, 45B Ridgeline 46A Vehicle inner side frame (left side frame) 46B Vehicle inner side frame (right side frame) 47A, 47B Ridgeline 34A Tether bracket (first tether bracket) 34B Left side tether bracket (2nd tether bracket or 3rd tether bracket) 34C Right side tether bracket (3rd tether bracket or 2nd tether bracket) 60A Mounting section (first mounting section) 60B Mounting portion (second mounting portion or third mounting portion) 60C Mounting section (third mounting section or second mounting section) 62A Base (1st base) 62B Base (2nd base or 3rd base) 62C Base (third base or second base) 63A Welded section (weld bead) 63B Welded section (weld bead) 63C Welding section (weld bead) 64A Left arm section (first connection section) 64B Left arm section (third or fifth connection section) 64C Left arm section (5th or 3rd connection section) 65A Welded section (weld bead) 65B Welded section (weld bead) 65C Welded section (weld bead) 66A Right arm section (second connection section) 66B Right arm section (4th or 6th connection section) 66C Right arm section (6th or 4th connection section) 67A Welded section (weld bead) 67B Welded section (weld bead) 67C Welded section (weld bead) 88 Top tether anchor (attachment) 92 Reinforcement 93B, 93C Ridgeline

Claims

1. a seat back frame including an upper frame extending in a seat width direction above the seat back, a pair of left and right side frames connected to both left and right end portions of the upper frame and extending downward from the both left and right end portions, respectively, and a lower frame extending in the seat width direction and having both end portions connected to lower ends of the pair of side frames, a first tether bracket disposed inside the seat back frame and to which an attachment tool at a tip of a top tether belt extending from a child seat is attached; The first tether bracket comprises: A first attachment portion to which the attachment tool is engaged; a first base portion extending from the first attachment portion toward a seat lower side and having a lower end connected to the lower frame; a first connecting portion extending from the first mounting portion to the left in the seat width direction and having a left end connected to the left side frame; a second connecting portion extending from the first mounting portion to the right in the seat width direction and having a right end connected to the right side frame; having The first base portion extends directly below the first mounting portion.

2. The first tether bracket has a first engaging portion fixed to the first mounting portion, The vehicle seat according to claim 1 , wherein the first engaging portion is provided to be contained within a vertical width of the first connecting portion and the second connecting portion.

3. a seat back frame including an upper frame extending in a seat width direction above the seat back, a pair of left and right side frames connected to both left and right end portions of the upper frame and extending downward from the both left and right end portions, respectively, and a lower frame extending in the seat width direction and having both end portions connected to lower ends of the pair of side frames, A reinforcement extending in a seat up-down direction and connecting an intermediate position of the upper frame and an intermediate position of the lower frame; a second tether bracket disposed on the inner side of the seat back frame to the left or right of the reinforcement and to which an attachment tool at a tip of a top tether belt extending from a child seat is attached; The second tether bracket comprises: A second mounting portion to which the mounting tool is engaged; a second base portion extending from the second mounting portion toward a seat lower side and having a lower end connected to the lower frame; A third connecting portion extending from the second mounting portion to the left in the seat width direction and having a left end connected to the left side frame or the reinforcement; A fourth connecting portion extending from the second mounting portion to the right in the seat width direction and having a right end connected to the reinforcement or the right side frame; having The second base portion extends directly below the second mounting portion.

4. The second tether bracket has a second engaging portion fixed to the second mounting portion, The vehicle seat according to claim 3 , wherein the second engaging portion is provided to be contained within a vertical width of the third connecting portion and the fourth connecting portion.

5. A third tether bracket is provided on the opposite side of the second tether bracket across the reinforcement on the inside of the seat back frame, and a mounting tool at the tip of a top tether belt extending from a child seat is engaged therewith. The third tether bracket is A third attachment portion to which the attachment tool is engaged; a third base portion extending from the third attachment portion toward a seat lower side and having a lower end connected to the lower frame; A fifth connecting portion extending from the third mounting portion to the left in the seat width direction and having a left end connected to the reinforcement or the left side frame; A sixth connecting portion extending from the third mounting portion to the right in the seat width direction and having a right end connected to the right side frame or the reinforcement; 4. The vehicle seat according to claim 3, further comprising:

6. 2. The vehicle seat according to claim 1, wherein at least one of the connecting portions is connected to the side frame via a weld bead, and the weld bead is formed across an entire area of ​​the connecting portion in a width direction.

7. 7. The vehicle seat according to claim 6, wherein all of the connecting portions are connected to the side frames via the weld beads, and the weld beads are formed across the entire widthwise area of ​​the connecting portions.

8. 6. The vehicle seat according to claim 3 or 5, wherein at least one of the connecting portions is connected to the side frame or the reinforcement via a weld bead, and the weld bead is formed across the entire widthwise area of ​​the connecting portion.

9. 9. The vehicle seat according to claim 8, wherein all of the connecting portions are connected to the side frames or the reinforcements via weld beads, and the weld beads are formed across the entire widthwise area of ​​the connecting portions.

10. 8. The vehicle seat according to claim 1, wherein at least one of the connecting portions overlaps a ridge line of the side frame when the seat is viewed from the front.

11. 10. The vehicle seat according to claim 3, wherein at least one of the connecting portions overlaps a ridge line of the side frame or the reinforcement in a front view of the seat.

12. 6. A vehicle seat comprising a vehicle seat according to claim 1 and a vehicle seat according to claim 5 arranged side by side to form a single vehicle seat.

Images