Vehicle seats

Abstract

To provide a seat for a vehicle which can contribute to reducing work load when assembling a seat back frame.SOLUTION: A seat back frame 25 includes left and right side frames 35 which include a plate-like part 35a which extends along vertical surface perpendicularly intersecting to rotation axis SX upwardly, a front wall 35b which is bent and molded inwardly by running from a front edge of the plate-like part 35a and a rear wall 35c which is bent and molded inwardly by running from a rear edge of the plate-like part 35a, a lower frame 36 which includes back region 51 which is jointed from a rearward direction to the rear wall 35c and connects the left and right side frames 35 mutually by being disposed to a rearward direction of the rotation axis SX and an upper frame 37 which connects the left and right side frame 35 mutually in an upward direction of the lower frame 36. The lower frame 36 includes reinforcement region 52 which spreads toward a frontward direction of the rotation axis SX and then is jointed to the front wall 35b from a rearward direction by running from a lower edge of the back region 51.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a vehicle seat provided with a seat back frame having left and right side frames each having a plate-like portion that extends along a vertical plane orthogonal to the axis of rotation around the axis of rotation and extends upward along the vertical plane, and a rear wall that is continuously bent inward from the rear edge of the plate-like portion to form a curved region that extends vertically from around the axis of rotation, a lower frame having a back region that is disposed behind the axis of rotation and joined to the rear wall from the rear to connect the left and right side frames to each other, and an upper frame that connects the left and right side frames to each other above the lower frame.

Background Art

[0002] Patent Document 1 discloses a vehicle seat (automobile seat) provided with a seat back that is reclinably connected to a seat cushion. The seat back has left and right side frames that extend upward in the vertical direction from the axis of rotation and support a seat back pad, a lower panel (lower frame) that is disposed behind the axis of rotation of the reclining and connects the left and right side frames to each other, and an upper cross member (upper frame) that connects the left and right side frames to each other above the lower panel. The left and right side frames, the lower panel, and the upper cross member form a square frame structure.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Each side frame has a plate-like section that extends along a vertical plane perpendicular to the reclining axis of rotation, and a rear wall that is continuous with the trailing edge of the plate-like section, bent inward, and extends vertically from the axis of rotation to form a curved region leading to the upper cross member. When assembling the seat back frame, the lower panel is joined to the rear wall of the side frame from the rear. Therefore, the side frame can be assembled to the lower panel from one direction. The side frame can be assembled to the lower panel with good work efficiency.

[0005] On the other hand, because the area between the two joint regions is flat, the torsional rigidity of the frame structure is not very high. High joint strength is required for the connection between the lower panel and the side frame to ensure sufficient torsional rigidity. This increases the workload of the joining process.

[0006] The present invention aims to provide a vehicle seat that can contribute to reducing the workload when assembling a seat back frame. [Means for solving the problem]

[0007] According to a first aspect of the present invention, a seat for a vehicle 11 has a seat back frame 25 having left and right side frames 35 that extend along a vertical plane perpendicular to the axis of rotation SX around the axis of rotation and extend upward along the vertical plane, a front wall 35b that extends inward from the front edge of the plate-like portion 35a, and a rear wall 35c that extends inward from the rear edge of the plate-like portion 35a, and a lower frame 36 that has a back region 51 that connects the left and right side frames 35 to each other, The aforementioned back region 51 is joined to the rear wall 35c,The lower frame 36 has a reinforcing region 52 that extends continuously from the lower edge of the back region 51 forward of the rotation axis SX and is joined to the front wall 35b, and the rear wall 35c has a high wall portion 61b that extends inward in the sheet width direction from the plate-like portion 35a in the direction of the rotation axis SX compared to the front wall 35b, and a low wall portion 61a that is positioned below the high wall portion 61b and extends shorter than the high wall portion 61b from the plate-like portion 35a in the direction of the rotation axis SX, and the front end of the reinforcing region 52 is positioned below the high wall portion 61b.

[0008] According to the second aspect, in addition to the configuration of the first aspect, A weld mark 63 is formed at the joint between the front wall 35b and the reinforcement area 52, and the weld mark 63 is located in a position that does not overlap with the rear wall 35c in a front view.

[0009] According to the third aspect, 1 In addition to the side configuration, A weld mark 54 is formed at the point where the rear wall 35c and the back region 51 are joined, and the weld mark 54 is located in a position that does not overlap with the front wall 35b when viewed from the front.

[0010] According to the fourth aspect, in addition to the structure of the first to third aspects, The upper edge of the back region 51 has a first edge 53a extending from the left-right central position in the left-right direction parallel to the rotation axis SX, and a second edge 53b extending upward from the left and right ends of the first edge 53a, each curving upward.

[0011] According to the fifth aspect, 4th aspect In addition to the configuration, The upper edge of the back region 51 includes a third edge 53c that extends outward from the upper end of the second edge 53b parallel to the axis of rotation SX and overlaps the side frame 35.

[0012] According to the sixth aspect, in addition to the configuration of the fifth aspect, The first edge 53a and the second edge 53b are provided with flanges 51b that extend forward, and the flanges 51b are continuous with the first edge 53a and the second edge 53b and extend to the upper end of the second edge 53b.

[0013] According to the seventh aspect, 6th In addition to the side configuration, A side frame flange 41 is formed on the rear wall 35c, extending forward from the inner end of the rear wall 35c. The side frame flange 41 extends in the vertical direction of the sheet, and its lower end is formed at the lower end of the high wall portion 61b on the inner side in the sheet width direction.

[0014] According to the eighth aspect, 7th In addition to the side configuration, The flange 51b is positioned further inward in the seat width direction than the side frame flange 41.

[0015] According to the ninth aspect, 1 In addition to the side configuration, The front wall 35b of the side frame 35 has an overlapping piece 62 that extends inward from the inner edge of the front wall 35b and overlaps the lower frame 36, and the overlapping piece 62 extends shorter than the high wall portion 61b in the direction of the rotation axis SX. [Effects of the Invention]

[0017] According to the first aspect, since the lower frame is joined to the individual side frames in a reinforcing region that extends forward from the lower edge of the back region toward the rotation axis in addition to the back region, the torsional rigidity of the seat back frame can be increased. Compared with the case where the lower frame is joined to the side frame only in the back region, the joining strength of the lower frame and the side frame can be reduced. Thus, the working load of joining can be reduced. 。

Brief Description of the Drawings

[0027] [Figure 1] It is a perspective view schematically showing the overall configuration of a vehicle seat according to the first embodiment of the present invention. [Figure 2] It is a perspective view schematically showing the structure of the seat frame. [Figure 3] It is a perspective view schematically showing the configuration of the seat cushion pad and the seat back pad. [Figure 4] It is a front view of the lower frame. [Figure 5] It is a rear view of the lower frame. [Figure 6] It is an enlarged cross-sectional view taken along line 6-6 of FIG. 4. [Figure 7] It is an enlarged bottom view of an enlarged portion of the seat back frame. [Figure 8] It is a front view of the upper frame. [Figure 9] It is an enlarged front view of an enlarged portion of the side frame. [Figure 10] It is a cross-sectional view taken along line 10-10 of FIG. 8. [Figure 11] It is an enlarged perspective view of the upper wall of the upper frame. [Figure 12] It is a cross-sectional view of the lower frame cut along a cutting plane passing through the central axis of the insertion hole. [Figure 13] It is a cross-sectional view of the side frame cut along a cutting plane passing through the central axis of the insertion hole and overlaid on the lower frame. [Figure 14]This is a cross-sectional view of the upper frame, which is superimposed on the side frame and cut along a cutting plane that passes through the central axis of the insertion hole. [Figure 15] This is a cross-sectional view of the lower frame and connecting shaft, cut by a plane passing through the central axis of the opening. [Figure 16] This is a front view of the upper frame in a modified form. [Figure 17] This diagram shows a cross-sectional view of the lower frame and connecting shaft, cut by a cross-section passing through the central axis of the opening, and also shows a connecting shaft relating to another specific example. [Figure 18] This is a schematic front view showing the support cylinders inserted into the upper and lower walls of the upper frame. [Figure 19] This is a cross-sectional view along line 19-19 in Figure 18. [Modes for carrying out the invention]

[0028] Embodiments of the present invention will be described below with reference to the attached drawings. In the following description, front-to-back, left-to-right, and up-and-down refer to directions as viewed from an occupant seated in a vehicle seat in a normal seating position (basic driving posture).

[0029] Figure 1 schematically shows the overall configuration of a vehicle seat (seat for a vehicle) according to one embodiment of the present invention. The vehicle seat 11 includes a slide rail 13 which is coupled to a floor panel 12 which functions as a component of the monocoque structure of the vehicle, and a slide rail which is movable in the front-rear direction. The vehicle seat 11 comprises a seat cushion 14 supported by a rod 13 to support the occupant's buttocks and thighs, a seat back 15 connected to the seat cushion 14 so as to be able to swing in the front-rear direction around a pivot axis SX to support the occupant's back, and a headrest 16 supported at the upper end of the seat back 15 to support the occupant's head. The seat cushion 14, seat back 15, and headrest 16 each have surface materials 14a, 15a, and 16a that enclose the internal pads. The surface materials 15a and 16a conform to the pad's contours and adhere closely to the outer surface of the pad through the action of suspension threads 17. Details of the pad will be described later. The vehicle seat 11 is configured for the left seat. If the vehicle seat 11 is to be used for the right seat, the left and right sides of the vehicle seat 11 should be swapped.

[0030] The seat cushion 14 is equipped with a side cover 18. A first lever (operator) 19a and a second lever (operator) 19b are attached to the side cover 18. The first lever 19a is supported so as to be able to swing around an axis parallel to the rotation axis SX. When the first lever 19a is pulled upward around the axis, the seat cushion 14 and seat back 15 move upward. When the first lever 19a is pushed downward around the axis, the seat cushion 14 and seat back 15 move downward. The second lever 19b is supported so as to be able to swing around the rotation axis SX. When the second lever 19b is pulled upward around the pivot axis SX, the lock between the seat cushion 14 and seat back 15 is released around the pivot axis SX. Swinging of the seat back 15 around the pivot axis SX is permitted. The seat back 15 is driven forward around the pivot axis SX by the action of a spring force. When an external force is applied to the seatback 15 in the rearward direction around the pivot axis SX against the spring force, the seatback 15 can be driven rearward around the pivot axis SX. When the second lever 19b is released from the upward force around the pivot axis SX, a lock is established between the seat cushion 14 and the seatback 15 around the pivot axis SX. The angle of the seatback 15 can be fixed around the pivot axis SX.

[0031] A third lever (operator) 19c is attached to the seat cushion 14. The third lever 19c is supported to swing freely around an axis parallel to the pivot axis SX. When the third lever 19c is pulled upward around the axis, the lock between the seat cushion 14 and the slide rail 13 is released. Linear movement of the seat cushion 14 on the slide rail 13 is permitted. When an external force is applied to the seat cushion 14 in a forward or backward direction, the seat cushion 14 can be displaced along the slide rail 13. When the third lever 19c is released from the upward force around the axis, a lock is established between the seat cushion 14 and the slide rail 13. The position of the seat cushion 14 in the front-rear direction on the slide rail 13 can be fixed.

[0032] The headrest 16 is fixed to a headrest pillar 21 that extends upward from the upper end of the seatback 15. The headrest pillar 21 is supported by the seatback 15 so as to be freely displaceable in the axial direction in the vertical direction. The height of the headrest 16 can be adjusted according to the displacement of the headrest pillar 21.

[0033] As shown in Figure 2, the vehicle seat 11 includes a seat frame 23 that supports the pad. The seat frame 23 includes a seat cushion frame 24 that supports the pad of the seat cushion 14, a seat back frame 25 that is connected to the seat cushion frame 24 so as to be able to swing around a pivot axis SX and supports the pad of the seat back 15, and a base frame 26 that is guided by a slide rail 13 so as to be able to move back and forth in the longitudinal direction and supports the seat cushion frame 24 on the slide rail 13. The seat cushion frame 24 is connected to the base frame 26 by a link mechanism 27. The link mechanism 27 has one end that is rotatably connected to the base frame 26 around a horizontal axis FH that extends in the left and right directions parallel to the pivot axis SX, and the other end that is rotatable around a horizontal axis SH that extends in the left and right directions parallel to the horizontal axis FH. The system includes a link member 28 having one end connected to the seat cushion frame 24. The link member 28 guides the vertical movement of the seat cushion frame 24 relative to the base frame 26 around the horizontal axis FH.

[0034] The seat cushion frame 24 comprises cushion side frames 24a extending alongside the individual slide rails 13, pan frames 24b connecting the cushion side frames 24a at the front end of the seat cushion 14, and connecting pipes 24c connecting the cushion side frames 24a at the rear end of the seat cushion 14. Multiple S-springs (not shown) are arranged between the pan frames 24b and the connecting pipes 24c. Each S-spring extends in a zigzag shape in the front-to-back direction. The zigzag shape is formed by alternating combinations of wires extending in the front-to-back direction and wires extending in the left-to-right direction.

[0035] A manual forward / backward movement device 29 is attached to the base frame 26. The third lever 19c is connected to the manual forward / backward movement device 29. The manual forward / backward movement device 29 switches the movement of the base frame 26 on the slide rail 13 in lock and unlock in response to the swinging of the third lever 19c.

[0036] A manual vertical movement device 31 is attached to the cushion side frame 24a of the seat cushion frame 24. The manual vertical movement device 31 includes a transmission mechanism 32 supported by the cushion side frame 24a and connected to a link mechanism 27. The transmission mechanism 32 is located outside the cushion side frame 24a and causes the link member 28 to rotate relative to the cushion side frame 24a about a horizontal axis SH in response to the driving force transmitted from the first lever 19a about an axis. The transmission mechanism 32 may include, for example, a drive gear fixed to the pivot axis of the first lever 19a and a driven gear fixed to the link member 28 about a horizontal axis SH.

[0037] The seat back frame 25 comprises left and right side frames 35 connected to the inside of individual cushion side frames 24a by a reclining unit (reclining mechanism) 34, a lower frame 36 connecting the lower ends of the side frames 35 to each other around the reclining unit 34, and an upper frame 37 connecting the upper ends of the side frames 34 to each other above the lower frame 36. The side frame 35 has a plate-like portion 35a that spreads out along a vertical plane perpendicular to the oscillation axis SX around the reclining unit 34 and extends upward along the vertical plane, a front wall 35b that is continuous from the front edge of the plate-like portion 35a and bent inward to form a curved region 38 that extends vertically from around the reclining unit 34, and a rear wall 35c that is continuous from the rear edge of the plate-like portion 35a and bent inward to form a curved region 39 that extends vertically from around the reclining unit 34. A side frame flange 41 is formed on the rear wall 35c, which is continuous with the inner end of the rear wall 35c and bent forward. Each side frame 35 is formed, for example, from a single sheet of metal. A headrest pillar guide 42, which supports the headrest pillar 21 so as to be slidable in the vertical direction, is fixed to the upper frame 37. Details of the upper frame 37 will be described later.

[0038] The reclining unit 34 includes a rotating body 43 that is supported so as to be rotatable relative to the seat cushion frame 24 and the seat back frame 25. A shaft 44 is coupled to one of the rotating bodies (in this case, the left rotating body) 43 coaxially with the pivot axis SX. The second lever 19b is fixed to the shaft 44. The relative rotation of the seat cushion frame 24 and the seat back frame 25 is locked and unlocked according to the rotation of the rotating body 43. The left and right reclining units 34 are connected to each other by a connecting shaft 45. The connecting shaft 45 can rotate around the pivot axis SX. The connecting shaft 45 transmits the rotation of one rotating body (in this case, the left rotating body) 43 to the other rotating body (in this case, the right rotating body) 43. Thus, operation of the second lever 19b transmits the rotation from one reclining unit 34 to the other reclining unit 34. It will be relayed to 34.

[0039] As shown in Figure 3, the seat cushion 14 further comprises a seat cushion pad 46 supported by a seat cushion frame 24 and encased in a surface material 14a. The seat back 15 further comprises a seat back pad 47 supported by a seat back frame 25 and encased in a surface material 15a. The seat cushion pad 46 and the seat back pad 47 are formed from an elastic material such as foamed urethane.

[0040] As shown in Figures 4 to 6, the lower frame 36 has a back region 51 positioned behind the pivot axis SX and joined to the rear wall 35c of the side frame 35 from the rear, connecting the left and right side frames 35 to each other, and a reinforcing region 52 that extends continuously from the lower edge of the back region 51 forward of the pivot axis SX and is joined to the front wall 35b from the rear. The reinforcing region 52 has a generatrix perpendicular to the plate-like portion 35a of the side frame 35 and curves around the pivot axis SX along the edge of the plate-like portion 35a. The torsional rigidity of the lower frame 36 around the pivot axis SX can be increased by the action of the curved reinforcing region 52. The lower frame 36 is formed, for example, from a single metal plate.

[0041] The back region 51 has a flat plate portion 51a that extends along the first plane Pf, and a flange 51b that is continuous with the upper edge of the flat plate portion 51a and bent forward. The upper edge of the flat plate portion 51a includes a first edge 53a that extends from the left and right central position in the left-right direction parallel to the pivot axis SX, a second edge 53b that extends from the left and right ends of the first edge 53a while curving upward, and a third edge 53c that extends outward from the upper end of the second edge 53b parallel to the pivot axis SX and overlaps the side frame 35. The flange 51b is continuous with the first edge 53a and the second edge 53b, is interrupted at the upper end of the second edge 53b and faces the side frame flange 41.

[0042] Weld marks 54 are established in the back region 51 at positions overlapping with the left and right side frames 35. Here, the weld marks 54 consist of weld beads formed along the edges of the side frames 35. The left and right side frames 35 are joined to the back region 51 of the lower frame 36 at the weld marks 54. Other welding methods such as spot welding and laser welding can also be used.

[0043] Two insertion holes 55 are formed in the back region 51, away from the individual side frames 35. The insertion holes 55 are spaced apart in the axial direction of the pivot axis SX at a distance that allows the lower frame 36 to be stably supported when supported by pins that stand upright in the vertical direction (direction of gravity). The insertion holes 55 have, for example, a circular contour.

[0044] In the back region 51, two openings 56 are formed, located away from the individual side frames 35 and closer to the center in the left-right direction than the two insertion holes 55. The openings 56 are spaced apart in the axial direction of the oscillation axis SX at a distance that allows the connecting shaft 45 to be stably supported when supported by a jig standing vertically (in the direction of gravity). The openings 56 have, for example, a circular contour.

[0045] As shown in Figure 5, the back region 51 has a first support surface 57 that extends within the first plane Pf and is supported from the rear during the assembly of the seat back frame 25. The insertion hole 55 and the opening 56 are drilled within the first support surface 57. Here, the opening 56 may be partially extended in a reinforcing region 52. The connecting shaft 45 has a rectangular body 58 that is positioned in front of the opening 56 and is held by a jig as described later. The rectangular body 58 is positioned in a cylindrical space surrounded by a virtual cylindrical surface that is perpendicular to the first plane Pf and inscribed in the opening 56. The rectangular body 58 can be formed, for example, by flattening a round tube to create a rectangular cross-sectional shape.

[0046] As shown in Figure 7, the front wall 35b of the side frame 35 is a pivot axis from the plate-shaped portion 35a. The front wall 35b has a first height Hf in the axial direction of the line SX. The front wall 35b is positioned offset in the axial direction of the oscillation axis SX from a virtual plane Se that is perpendicular to the oscillation axis SX and includes the edge of the lower frame 36. The rear wall 35c of the side frame 35 is adjacent to the front wall 35b with a space 59 in between, along the periphery of the plate-like portion 35a around the oscillation axis SX, and has a low wall 61a having a first height Hf in the axial direction of the oscillation axis SX from the plate-like portion 35a, and a high wall portion 61b that is continuous with the low wall portion 61a and has a second height Hs greater than the first height Hf in the axial direction of the oscillation axis SX from the plate-like portion 35a. The curved region 38 of the front wall 35b and the curved region 39 of the rear wall 35c are separated by the space 59. As shown in Figure 4, the high wall portion 61b is positioned above a virtual plane Le that is perpendicular to the first plane Pf and touches the front edge of the reinforcement region 52 from above.

[0047] As shown in Figure 7, an overlapping piece 62 is formed on the front wall 35b of the side frame 35, extending inward from the inner edge of a first height Hf and overlapping the reinforcing area 52 of the lower frame 36 from the front. A weld mark 63 is established on the edge of the overlapping piece 62 at a position overlapping with the reinforcing area 52. Here, the weld mark 63 consists of a weld bead formed along the edge of the overlapping piece 62. The left and right side frames 35 are joined to the reinforcing area 52 of the lower frame 36 at the weld mark 63. Other welding methods such as spot welding and laser welding can also be used. As shown in Figure 4, the overlapping piece 63 is positioned below a virtual plane Le that is perpendicular to the first plane Pf and touches the front edge of the reinforcing area 52 from above.

[0048] As shown in Figure 5, each side frame 35 has a second support surface 64 that extends within a second plane Ps, which is set in a predetermined positional relationship with respect to the first plane Pf, and is supported from the rear when assembling the seat back frame 25. Here, the second plane Ps is set parallel to the first plane Pf. The rear wall 35c of the side frame 35 has an insertion hole 65 that opens into the second support surface 64 at a position away from the lower frame 36. The insertion hole 65 has, for example, a circular contour.

[0049] As shown in Figure 2, an auxiliary insertion hole 66 is formed in the rear wall 35c of each side frame 35, above the insertion hole 65 and away from the upper frame 37. The auxiliary insertion hole 66 is positioned vertically away from the insertion hole 65 at a distance that allows the side frame 35 to be stably supported in cooperation with the insertion hole 65 when the side frame 35 is supported by a pin that stands upright in the vertical direction (direction of gravity), similar to the insertion hole 65. The auxiliary insertion hole 66 has, for example, a circular contour. The auxiliary insertion hole 66 expands within an auxiliary plane set in a predetermined positional relationship with the first plane Pf and opens into an auxiliary receiving surface that is supported from the rear during the assembly of the seat back frame 25.

[0050] As shown in Figure 8, the upper frame 37 has a front wall 69 formed by bending a sheet material and separated by an upper ridge 67 and a lower ridge 68 extending horizontally, an upper wall 71 that is continuous with the upper ridge 67 and extends to the rear, an upper upright wall 72 that is bent upward from the rear end of the upper wall 71, a lower wall 73 that is continuous with the lower ridge 68 and extends to the rear, and a lower upright wall 74 that is bent downward from the rear end of the lower wall 73. A first flange 75 is connected to the upper upright wall 72, which is continuous with the upper end of the upper upright wall 72 and bent forward. The first flange 75 is continuous horizontally along the upper edge of the upper upright wall 72 over its entire length. A second flange 76 is connected to the lower upright wall 74, which is continuous with the lower end of the lower upright wall 74 and bent forward. The second flange 76 is continuous horizontally along the lower edge of the lower upright wall 74 over its entire length.

[0051] The front wall 69 is formed by folding forward at two points on the left and right in the horizontal direction, forming recesses along the vertical valley fold lines 77, and each has connecting pieces 69a extending outward. The connecting pieces 69a are further folded backward on the outside of the recesses in the horizontal direction, forming ridges along the vertical mountain fold lines 78. As the front wall 69 deforms, the upper and lower upright walls 7 4 deforms similarly. The upper frame 37 is formed, for example, from a single sheet of metal.

[0052] A weld mark 79 is established on the front wall 69 outside the horizontal fold line 78. Here, the weld mark 79 consists of weld beads formed along the edges of the left and right side frames 35. Corresponding to the weld marks 79, weld marks 81 and 82 are established on the upper wall 72 and lower wall 74. Here, the weld marks 81 and 82 consist of weld beads formed along the edges of the left and right side frames 35. The upper frame 37 is fixed to the left and right side frames 35 by the weld marks 79, 81, and 82. Other welding methods such as spot welding and laser welding can also be used.

[0053] As shown in Figure 9, the inner edge of the front wall 35b has a projection 83 that extends inward from a virtual contour line 83a corresponding to the edge of the upper frame 37 and overlaps the front wall 69 of the upper frame 37 from the rear. The front wall 69 of the upper frame 37 forms a weld mark 79 with the projection 83. The inner edge of the rear wall 35c has an upper overlapping area 84 that overlaps the upper upright wall 72 of the upper frame 37 from the rear, and a lower overlapping area 85 below the upper overlapping area 84, spaced apart from the upper overlapping area 84, that overlaps the lower upright wall 74 of the upper frame 37 from the rear. The upper upright wall 72 of the upper frame 37 forms a weld mark 81 with the upper overlapping area 84. Similarly, the lower upright wall 74 of the upper frame 37 forms a weld mark 82 with the lower overlapping area 85.

[0054] As shown in Figure 10, the upper frame 37 has a first through-hole 87 formed in the upper wall 71 for receiving the headrest pillar guide 86, and a second through-hole 88 formed in the lower wall 73 for receiving the headrest pillar guide 86. The headrest pillar guide 86 supports the headrest pillar 21 so as to be displaceable in the axial direction. A positioning flange 89 is formed on the headrest pillar guide 86, extending in a direction perpendicular to the axis. When the headrest pillar guide 86 is inserted into the first through-hole 87 and the second through-hole 88 from above, the positioning flange 89 contacts the upper wall 71 from above to position the headrest pillar guide 86 in the axial direction. The headrest pillar guide 86 can be molded from, for example, a resin material.

[0055] Support hole flanges 91 are formed around the periphery of the first through hole 87 and the second through hole 88, respectively, by being bent downwards. The headrest pillar guide 86 is press-fitted into the support hole flanges 91. The support hole flanges 91 fix the headrest pillar guide 86 to the upper frame 37. The support hole flanges 91 can prevent the headrest pillar guide 86 from coming out of the upper frame 37.

[0056] As shown in Figure 11, a receiving piece 92 is formed on the first flange 75 behind the first through hole 87, which is bent downward from the leading edge of the first flange 75. The receiving piece 92 receives the headrest pillar guide 86 from the rear. The load acting on the headrest pillar guide 86 from the front is supported by the upper wall 72 of the upper frame 37. Alternatively, the receiving piece 92 may be bent upward from the leading edge of the first flange 75.

[0057] As shown in Figure 8, a bead (reinforcement shape) 93 is formed in the recess of the front wall 69, extending and intersecting the valley fold line 77, reinforcing the rigidity of the front wall 69 in the bending direction. The bead 93 extends horizontally in the left-right direction. Similarly, a bead (reinforcement shape) 94 is formed on the front wall 69, extending and intersecting the headrest pillar 21 in a front view, reinforcing the rigidity of the front wall 69 in the in-plane direction. The bead 94 is inclined to displace upward from the lowest end near the center outwards.

[0058] Two insertion holes 95 are formed in the front wall 69 in the area between the two recesses. The insertion holes 95 are positioned at a distance in the axial direction of the pivot axis SX such that the upper frame 37 is stably supported when it is supported by a pin that stands upright in the vertical direction (direction of gravity). The insertion holes 95 have, for example, a circular contour. As shown in Figure 10, the insertion holes 95 expand within a third plane Pt, which is set in a predetermined positional relationship with the first plane Pf (or auxiliary plane), and open at a third receiving surface 96 that is supported from the rear when the seat back frame 25 is assembled.

[0059] Next, the manufacturing method of the seat back frame 25 will be described. For the assembly of the seat back frame 25, a lower frame 36, left and right side frames 35, and an upper frame 37 are prepared. As shown in Figure 12, the lower frame is installed on the first plane Pf. For installation, the insertion pin 101 is inserted into the insertion hole 55. The insertion pin 101 is formed in a cylindrical shape, for example, having an axis that stands upright in the vertical direction (direction of gravity). The insertion pin 101 has a step 101a that defines the first plane Pf perpendicular to the axis. The first receiving surface 57 of the lower frame 36 is received by the step 101a of the insertion pin 101. The lower frame 36 is positioned relative to the first plane Pf by inserting the insertion pin 101 into the insertion hole 55.

[0060] Next, as shown in Figure 13, the left and right side frames 35 are placed on the lower frame 36. When placing them, the insertion pins 102 are inserted into the insertion holes 65 of the side frames 35. The insertion pins 102 are formed in a cylindrical shape, for example, having an axis that stands upright in the vertical direction (direction of gravity). The insertion pins 102 have a step 102a that defines a second plane Ps perpendicular to the axis. The second receiving surface 64 of the side frame 35 is received by the step 102a of the insertion pins 102. At this time, an auxiliary insertion pin (not shown) is further inserted into the auxiliary insertion hole 66 of the side frame 35. The auxiliary insertion pins are formed in a cylindrical shape, for example, having an axis that stands upright in the vertical direction (direction of gravity). The auxiliary insertion pins have a step that defines an auxiliary plane. The auxiliary receiving surface of the side frame 35 is received by the step of the auxiliary insertion pin. The side frames 35 are supported by a second plane Ps and an auxiliary plane. Since the second plane Ps and the auxiliary plane are positioned in a predetermined positional relationship with respect to the first plane Pf, the left and right side frames 35 can be precisely positioned relative to the lower frame 36. The side frames 35 can be superimposed on the lower frame 36 from the axial direction of the insertion pins 102. The rear wall 35c of the side frame 35 is superimposed on the back region 51 of the lower frame 36. The front wall 35b of the side frame 35 is superimposed on the reinforcement region 52 of the lower frame 36 from the axial direction of the insertion pins 102. The side frames 35, thus positioned, are welded to the lower frame 36. Weld marks 54 and 63 are formed.

[0061] Next, as shown in Figure 14, the upper frame 37 is positioned on the left and right side frames 35. For positioning, the insertion pin 103 is inserted into the insertion hole 95 of the upper frame 35. The insertion pin 103 is formed in a cylindrical shape, for example, having an axis that stands upright in the vertical direction (direction of gravity). The insertion pin 103 has a step 103a that defines a third plane Pt perpendicular to the axis. The third receiving surface 96 of the upper frame 37 is received by the step 103a of the insertion pin 103. Since the third plane Pt is positioned in a predetermined positional relationship with respect to the first plane Pf and the auxiliary plane, the upper frame 37 can be positioned accurately with respect to the left and right side frames 35. The upper frame 37 can be superimposed on the side frames 35 from the axial direction of the insertion pin 103. The front wall 69 of the upper frame 37 is superimposed on the projection 83 from the axial direction of the insertion pin 103. The upper wall 72 of the upper frame 37 is superimposed on the upper overlapping area 84 of the rear wall 35c from the axial direction of the insertion pin 103. Interference between the upper wall 72 and the front wall 35b can be avoided during superimposition. Similarly, the lower wall 74 of the upper frame 37 is superimposed on the lower overlapping area 85 of the rear wall 35c from the axial direction of the insertion pin 103. Interference between the lower wall 74 and the front wall 35b can be avoided during the fitting process. The upper frame 37, thus positioned, is welded to the left and right side frames 35. Weld marks 79, 81, and 82 are formed.

[0062] As shown in Figure 15, when the lower frame 36 is received by the insertion pin 101, the jig 104 enters the opening 56 of the back region 51. A square groove 104a is cut into the tip of the jig 104 coaxially with the pivot axis SX. The rectangular body 58 of the connecting shaft 45 can be fitted into the square groove 104a. In this way, the connecting shaft 45 can be positioned relative to the individual side frames 35. Both ends of the positioned connecting shaft 45 are welded to the rotating body 43 of the reclining unit 34.

[0063] In the seat back frame 25 according to this embodiment, the lower frame 36 has a reinforcing region 52 that extends continuously from the lower edge of the back region 51 forward of the pivot axis SX and is joined to the front wall 35b of the side frame 35 from the rear. The lower frame 36 is joined to the individual side frames 35 not only by the back region 51 but also by the reinforcing region 52 that extends from the lower edge of the back region 51 forward of the pivot axis SX. The torsional rigidity of the seat back frame 25 can be increased. The joining strength of the lower frame 36 and the side frames 35 can be reduced compared to the case where the lower frame 36 is joined to the side frames only by the back region 51. Thus, the workload of joining can be reduced. Moreover, when assembling the seat back frame 25, the lower frame 36 can be assembled to the side frames 35 from the rear. The side frames 35 can be assembled to the lower frame 36 from one direction. The workability of assembly is not impaired.

[0064] The side frame 35 has a space 59 formed between the front wall 35b and the rear wall 35c along the periphery of the plate-shaped portion 35a around the reclining unit 34. The front wall 35b, which is bent and formed along the periphery of the plate-shaped portion 35a around the reclining unit 34, and the rear wall 35c, which is also bent and formed along the periphery of the plate-shaped portion 35a around the reclining unit 34, are separated by the space 59. When drawing the side frame 35, the shape accuracy of the front wall 35b and the rear wall 35c can be improved compared to when the front wall 35b and the rear wall 35c are continuous around the reclining unit 34. Therefore, the assembly of the side frame 35 to the lower frame 36 is stable.

[0065] In this embodiment, an opening 56 is formed in the back region 51 of the lower frame 36 to allow the jig 104 to pass through when assembling the seat back frame 25. On the other hand, a rectangular body 58 is formed on the connecting shaft 45, positioned in front of the opening 56 and held by the jig 104. When assembling the seat back frame 25, the jig 104 can be inserted into the opening 56 from the rear. The rectangular body 58 of the connecting shaft 45 can be held by the jig 104. In this way, the connecting shaft 45 can be positioned relative to the left and right rotating bodies 43. The connecting shaft 45 can be joined to each rotating body 43 with good work efficiency.

[0066] A first support surface 57 is formed in the back region 51 of the lower frame 36, which extends within a first plane Pf and is supported from the rear. A second support surface 64 is formed on the rear wall 35c of the side frame 35, which extends within a second plane Ps set in a predetermined positional relationship with the first plane Pf, and is supported from the rear, positioning the side frame 35 relative to the lower frame 36. When assembling the seat back frame 25, the lower frame 36 can be physically supported by the first support surface 57. When the side frame 35 is physically supported by the second support surface 64, the left and right side frames 35 can be positioned relative to the lower frame 36 based on the positional relationship between the first plane Pf and the second plane Ps. The side frames 35 can be easily positioned relative to the lower frame 36.

[0067] In addition, the upper frame 37 has a third receiving surface 96 that extends within a third plane Pt, which is set in a predetermined positional relationship with the second plane Ps, and positions the upper frame 37 relative to the side frame 35 when supported from the rear. When the upper frame 37 is physically supported by the third receiving surface 96, the upper frame 37 can be positioned relative to the side frame 35 based on the positional relationship between the second plane Ps and the third plane Pt. The upper frame 37 can be easily positioned relative to the side frame 35.

[0068] In the side frame 35 according to this embodiment, a projection 83 is formed on the inner edge of the front wall 35b, extending inward from a virtual contour line 83a corresponding to the shape of the upper frame 37 and overlapping the front wall 69 of the upper frame 37 from the rear. The upper frame 37 can be assembled from the front onto the left and right side frames 35, which are arranged at the intervals required for assembly. At this time, the front wall 35b of the side frame 35 does not interfere with the upper and lower upright walls 72 and 74 of the upper frame 37, which are located behind the front wall 69. In this way, the work efficiency when assembling the upper frame 37 can be improved.

[0069] The front wall 69 of the upper frame 37 is formed by bending forward at two points on the left and right sides in the horizontal direction, forming a recess along the vertical valley fold line 77, and has connecting pieces 69a extending toward the projection 83. A bead 93 is formed in the recess of the front wall 69, extending while intersecting the valley fold line 77 and reinforcing the rigidity in the bending direction. The rigidity of the front wall 69 can be increased against bending along the valley fold line 77. Therefore, deformation of the upper frame 37 can be suppressed during assembly. The efficiency of the assembly work can be increased.

[0070] A bead 94 is formed on the front wall 69 of the upper frame 37, extending while intersecting the headrest pillar 21 in a front view and reinforcing rigidity in the in-plane direction. In the upper frame 37, the rigidity of the front wall 69 can be increased in correspondence with the first through hole 87 in the upper wall 71 and the second through hole 88 in the lower wall 73. Therefore, deformation of the upper frame 37 can be suppressed during assembly. The efficiency of the assembly work can be increased.

[0071] In the upper frame 37 according to this embodiment, a receiving piece 92 is formed on the first flange 75 behind the first through hole 87, and is continuous with the leading edge of the first flange 75 and bent downward. The rigidity of the front wall 69 can be increased in correspondence with the first through hole 87 in the upper wall 71 and the second through hole 88 in the lower wall 73. Therefore, deformation of the upper frame 37 can be suppressed during assembly. The efficiency of assembly can be increased.

[0072] As shown in Figure 16(A), a cutout 105 may be formed in the front wall 69 of the upper frame 37 between the left and right beads 94. The cutout 105 can contribute to reducing the weight of the upper frame 37. The beads 94 can suppress the decrease in rigidity that occurs as a result of the formation of the cutout 105. In addition, as shown in Figure 16(B), in addition to the cutout 105 in the front wall 69, a cutout 106 may be formed in the lower upright wall 74 of the upper frame 37. The cutout 106 can contribute to further reducing the weight of the upper frame 37. In addition, as shown in Figure 16(C), the lower upright wall 74 itself may be shortened in the vertical direction. In this case, the beads 93 may be extended toward the mountain fold line 78.

[0073] As shown in Figure 17, the connecting shaft 45 itself may be formed from a rectangular tube. In this case, the rectangular tube forms a rectangular body 58 in front of the opening 56.

[0074] As shown in Figure 18, support cylinders 107 are fixed to the upper wall 71 and lower wall 73 of the upper frame 36, inserted into first through-holes 87 and second through-holes 88 to support the headrest pillar guide 86. The support cylinders 107 are formed from, for example, a metal material. Here, small pieces 108 and 109 are bent upward and downward from the periphery into the first through-holes 87 and second through-holes 88, respectively. As shown in Figure 19, the individual pieces 108 and 109 are superimposed on the outer surface of the support cylinder 107. The pieces 108 and 109 are welded to the support cylinder 107. The welding can be performed from the front, as with the welding of the upper frame 37 and side frames 35, thus improving the work efficiency of assembling the seat frame 23. The headrest pillar guide 86 is press-fitted into the support cylinder 107.

[0075] The support cylinder 107 is supported from the rear by the receiving piece 92. The rigidity of the front wall 69 can be increased through the cooperation of the support cylinder 107 and the receiving piece 92. Therefore, deformation of the upper frame 37 can be suppressed during assembly of the upper frame 37. The efficiency of the assembly work can be increased. [Explanation of symbols]

[0076] 11...Vehicle seat (vehicle seat), 21...Headrest pillar, 24...Seat cushion frame, 25...Seat back frame, 34...Reclining mechanism (reclining unit), 35...Side frame, 35a...Plate-shaped part, 35b...Front wall, 35c...Rear wall, 36...Lower frame, 37...Upper frame, 38...Curved area, 39...Curved area, 45...Connecting member (connecting shaft), 51...Back area, 52...Reinforcement area, 56...Opening, 57...First receiving surface, 58...Angular body, 59...Space, 64...Second receiving surface, 67...Upper ridge, 68...Lower ridge, 69...Front wall, 69a...Connecting piece, 71...Upper wall, 72...Upper upright wall, 73...Lower wall, 74...Lower upright wall, 75...Flange (first flange), 77...Valley fold line, 83...Protruding piece, 83a...Virtual contour line, 86...Headrest pillar guide, 87...Through hole (first through hole), 88...Through hole (second through hole), 92...Receiving piece, 93...Reinforcement shape (bead), 94...Reinforcement shape (bead), 96...Third receiving surface, 104...Jig, 107...Support cylinder, Pf...First plane, Ps...Second plane, Pt...Third plane, SX...Rotation axis (oscillation axis).

Claims

1. Left and right side frames (35) having a plate-like portion (35a) that extends upward along a vertical plane perpendicular to the axis of rotation (SX) around the axis of rotation, a front wall (35b) that extends inward from the front edge of the plate-like portion (35a), and a rear wall (35c) that extends inward from the rear edge of the plate-like portion (35a), A vehicle seat (11) comprising a seat back frame (25) having a lower frame (36) having a back region (51) that connects the left and right side frames (35) to each other, The aforementioned back region (51) is joined to the aforementioned rear wall (35c), The lower frame (36) has a reinforcing region (52) that extends continuously from the lower edge of the back region (51) forward of the rotation axis (SX) and is joined to the front wall (35b), The rear wall (35c) is In the direction of the rotation axis (SX), the plate-like portion (35a) extends inward in the sheet width direction from the front wall (35b), and It has a low wall portion (61a) positioned below the high wall portion (61b) and extending shorter than the high wall portion (61b) from the plate-like portion (35a) in the direction of the rotation axis (SX), A vehicle seat characterized in that the front end of the reinforced area (52) is positioned below the high wall portion (61b).

2. In the vehicle seat according to claim 1, A weld mark (63) is formed at the location where the front wall (35b) and the reinforcement area (52) are joined. A vehicle seat characterized in that the welding marks (63) are located in a position that does not overlap with the rear wall (35c) when viewed from the front.

3. In the vehicle seat according to claim 1, A weld mark (54) is formed at the location where the rear wall (35c) and the back region (51) are joined. The seat for a vehicle is characterized in that the welding marks (54) are located in a position that does not overlap with the front wall (35b) when viewed from the front.

4. In a vehicle seat according to any one of claims 1 to 3, The upper edge of the aforementioned back region (51) is A first edge (53a) extends from the left-right central position in the left-right direction parallel to the rotation axis (SX), A seat for a vehicle, characterized by having a second edge (53b) that curves upward from the left and right ends of the first edge (53a).

5. In the vehicle seat according to claim 4, The upper edge of the aforementioned back region (51) is A seat for a vehicle, characterized in that it includes a third edge (53c) that extends outward from the upper end of the second edge (53b) parallel to the axis of rotation (SX) and overlaps the side frame (35).

6. In the vehicle seat according to claim 5, The first edge (53a) and the second edge (53b) are provided with flanges (51b) that extend forward. The flange (51b) is continuous with the first edge (53a) and the second edge (53b), and extends to the upper end of the second edge (53b), characterized in that it is a seat for a vehicle.

7. In the vehicle seat according to claim 6, A side frame flange (41) is formed on the rear wall (35c) that extends forward from the inner end of the rear wall (35c). The side frame flange (41) extends in the vertical direction of the seat, A vehicle seat characterized in that the lower end of the side frame flange (41) is formed at the lower end of the high wall portion (61b) on the inside in the seat width direction.

8. In the vehicle seat according to claim 7, The seat for a vehicle is characterized in that the flange (51b) is positioned further inward in the seat width direction than the side frame flange (41).

9. In the vehicle seat according to claim 1, The front wall (35b) of the side frame (35) has an overlapping piece (62) that extends inward from the inner edge of the front wall (35b) and overlaps the lower frame (36). The overlapping piece (62) is characterized in that it extends shorter than the high wall portion (61b) in the direction of the rotation axis (SX).

Images