Vehicular seat

Abstract

To provide a vehicular seat that has a seat back whose upper part can be inclined with respect to a lower part, in which an actuator for inclining the lower part with respect to the upper part is arranged compactly.SOLUTION: In a vehicular seat 1, which has a seat back 5 whose upper part can be inclined with respect to a lower part, a seat back frame 10 includes a base frame 11, a movable frame 12 inclinably joined to the base frame, and an actuator 98 that has one end connected to the base frame and the other end connected to the movable frame, which performs at least either of operation of making the one end approach the other end and operation of separating the one end from the other end. A receiving concave part 105 for receiving at least a portion of the actuator is formed in at least either of the base frame and the movable frame.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a seat back of a vehicle seat, and particularly to a folding seat back in which the upper part is tiltable in the front-rear direction with respect to the lower part of the seat back frame.

Background Art

[0002] There is known a vehicle seat provided with a seat back in which the upper part is tiltable in the front-rear direction with respect to the lower part, so-called a folding seat back. In such a folding seat back, by tilting the upper part of the seat back with respect to the lower part, the shape of the seat back can be made to fit better to the physique of the seated person, and thus there is an advantage that the comfort of the vehicle seat is improved.

[0003] Patent Document 1 discloses a vehicle seat device provided with a folding mechanism driving device for tilting the upper part of the seat back with respect to the lower part of the seat back. The vehicle seat device of Patent Document 1 includes a pair of left and right side frames constituting the skeleton of the lower part of the seat back, and a motor supported by the side frames. The motor exerts a driving force for tilting the upper part of the seat back with respect to the lower part of the seat back.

[0004] Patent Document 2 discloses a vehicle seat having a shoulder support mechanism for adjusting the inclination of the upper part of the seat back with respect to the lower part of the seat back. The vehicle seat of Patent Document 2 includes a lower frame having a rectangular frame shape and an upper frame formed in a U shape. Both lower end portions of the upper frame are rotatably attached to both upper sides of the upper part of the lower frame, respectively. A motor of a shoulder support mechanism for adjusting the inclination of the upper part of the seat back is fixed substantially at the center of the upper part of the lower frame.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] In a vehicle seat provided with a folding seat back, an actuator for displacing the upper part of the seat back relative to the lower part may be installed. However, installing the actuator may lead to an increase in the size of the seat. Therefore, in a vehicle seat provided with a folding seat back, it has been desired to develop a structure in which an actuator for tilting the upper part of the seat back relative to the lower part can be arranged compactly.

[0007] In view of the above background, an object of the present invention is to arrange an actuator for tilting the lower part relative to the upper part compactly in a vehicle seat in which the upper part of the seat back is tiltable relative to the lower part.

Means for Solving the Problems

[0008] In order to solve the above problems, an aspect of the present invention is a vehicle seat (1) in which the upper part of a seat back (5) is tiltable relative to the lower part, wherein the seat back frame (10) has a base frame (11), a movable frame (12) tiltably coupled to the base frame, one end connected to the base frame, and the other end connected to the movable frame, and an actuator (98) that performs at least one of the operations of approaching and separating the one end and the other end, and at least one of the base frame and the movable frame is provided with a receiving recess (105) for receiving at least a part of the actuator.

[0009] According to this aspect, at least a part of the actuator is received in the receiving recess. Thereby, in a vehicle seat provided with a seat back whose upper part is tiltable relative to the lower part, the actuator for tilting can be arranged compactly.

[0010] In the above aspect, preferably, the base frame includes a pair of left and right base side members (14) and a base upper member (15) connecting the upper portions of the base side members, and the movable frame has a pair of left and right movable side members (38) each tiltably coupled to the base side members and a movable upper member (39) connecting the upper portions of the movable side members. One end is connected to the base upper member, and the other end is connected to the movable upper member.

[0011] According to this aspect, by driving the actuator, the actuator can be disposed at a position where the movable frame rotates with respect to the base frame.

[0012] In the above aspect, preferably, the movable side member and the corresponding base side member, one end of the actuator and the base upper member, and the other end of the actuator and the movable upper member are rotatably connected about axes (X, Y, Z) extending in the left - right direction, respectively.

[0013] According to this aspect, by driving the actuator, the actuator can be connected to the movable frame and the base frame so that the movable frame rotates with respect to the base frame.

[0014] In the above aspect, preferably, the receiving recess is provided on the front surface of the base upper member.

[0015] According to this aspect, the receiving recess can be provided at a position where it is easy to accommodate the actuator.

[0016] In the above aspect, preferably, the receiving recess is recessed in a direction away from the movable upper member in the base upper member.

[0017] According to this aspect, the receiving recess can be provided at a position where it is easy to accommodate the actuator.

[0018] In the above aspect, preferably, the actuator includes a motor (98A), a gear box (98C) connected to the output shaft of the motor, and a lead screw (98B) that slides relative to the gear box by driving of the motor. The gear box is rotatably connected to the base upper member, and an end of the lead screw is rotatably connected to the movable upper member.

[0019] According to this aspect, the actuator can be connected to the movable frame and the base frame such that the movable frame rotates with respect to the base frame by driving of the actuator.

[0020] In the above aspect, preferably, the axial direction of the output shaft of the motor and the axial direction of the lead screw are orthogonal to each other, and the lead screw is provided at a position biased in either the left or right direction in the receiving recess.

[0021] According to this aspect, a space for accommodating the motor can be secured.

[0022] In the above aspect, preferably, a headrest frame (64) is coupled to the movable frame, and at least a part of the actuator is located behind the headrest frame.

[0023] According to this aspect, the actuator can be disposed rearward compared to the case where the actuator is located in front of the headrest frame. Therefore, it is possible to prevent the actuator from giving a foreign body sensation to the seated person.

Advantages of the Invention

[0024] One aspect of the present invention is a vehicle seat (1) in which the upper part of the seat back (5) is tiltable with respect to the lower part, the seat back frame (10) having a base frame (11), a movable frame (12) tiltably coupled to the base frame, one end connected to the base frame, and the other end connected to the movable frame, and an actuator (98) that performs at least one of the operations of approaching and separating the one end and the other end, and at least one of the base frame and the movable frame is provided with a receiving recess (105) for receiving at least a part of the actuator.

[0025] According to this aspect, at least a part of the actuator is received in the receiving recess. Thereby, in a vehicle seat provided with a seat back whose upper part is tiltable with respect to the lower part, the actuator for tilting can be arranged compactly.

[0026] In the above aspect, preferably, the base frame includes a pair of left and right base side members (14) and a base upper member (15) connecting the upper parts of the base side members, the movable frame has a pair of left and right movable side members (38) each tiltably coupled to the base side members and a movable upper member (39) connecting the upper parts of the movable side members, the one end is connected to the base upper member, and the other end is connected to the movable upper member.

[0027] According to this aspect, by driving the actuator, the actuator can be arranged at a position where the movable frame rotates with respect to the base frame.

[0028] In the above aspect, preferably, the movable side member and the corresponding base side member, the one end of the actuator and the base upper member, and the other end of the actuator and the movable upper member are each rotatably connected about axes (X, Y, Z) extending in the left-right direction.

[0029] According to this aspect, the actuator can be connected to the movable frame and the base frame so that the movable frame rotates with respect to the base frame by driving the actuator.

[0030] In the above aspect, preferably, the receiving recess is provided on the front surface of the base upper member.

[0031] According to this aspect, the receiving recess can be provided at a position where it is easy to accommodate the actuator.

[0032] In the above aspect, preferably, the receiving recess is recessed in the base upper member in a direction away from the movable upper member.

[0033] According to this aspect, the receiving recess can be provided at a position where it is easy to accommodate the actuator.

[0034] In the above aspect, preferably, the actuator includes a motor (98A), a gear box (98C) connected to the output shaft of the motor, and a lead screw (98B) that slides relative to the gear box by driving the motor. The gear box is rotatably connected to the base upper member, and an end of the lead screw is rotatably connected to the movable upper member.

[0035] According to this aspect, the actuator can be connected to the movable frame and the base frame so that the movable frame rotates with respect to the base frame by driving the actuator.

[0036] In the above aspect, preferably, the axial direction of the output shaft of the motor and the axial direction of the lead screw are orthogonal to each other, and the lead screw is provided at a position biased in either the left or right direction in the receiving recess.

[0037] According to this aspect, a space for accommodating the motor can be secured.

[0038] In the above aspect, preferably, a headrest frame (64) is coupled to the movable frame, and at least a part of the actuator is located behind the headrest frame.

[0039] According to this aspect, the actuator can be arranged at the rear compared to the case where the actuator is located in front of the headrest frame. Therefore, it is possible to prevent the actuator from giving a foreign body sensation to the seated person.

Brief Description of the Drawings

[0040]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Embodiments for Carrying out the Invention

[0041] Hereinafter, with reference to the drawings, an embodiment in which the vehicle seat according to the present invention is applied to an automobile seat will be described. In the following description, left and right are defined based on the occupant sitting on the seat.

[0042] Also, the direction toward the center in the left-right direction (also referred to as the seat width direction) of the seat when viewed from the front is described as the inner side of the seat (or, inside the seat). Also, the direction away from the center in the left-right direction of the seat is described as the outer side of the seat (or, outside the seat).

[0043] <Overall Configuration of the Seat> As shown in FIG. 1, the vehicle seat (hereinafter, seat 1) is placed on the floor 3 that defines the bottom of the passenger compartment 2 (also referred to as the vehicle compartment) of the automobile. The seat 1 has a seat cushion 4 provided on the floor 3, a seat back 5 extending upward from the rear of the seat cushion 4, and a headrest 6 provided on the upper part of the seat back 5. The seat cushion 4 constitutes a seating surface 4S and supports the buttocks of the seated person. The seat back 5 constitutes a backrest surface 5S facing forward and supports the back of the seated person. The headrest 6 is arranged behind the head of the seated person. The seat cushion 4 may be supported by the floor 3 so as to be slidable back and forth via a slide device (not shown).

[0044] The seat back 5 includes a base portion 8 that constitutes the lower half of the backrest surface 5S, and a movable portion 9 that constitutes the upper half of the backrest surface 5S. The movable portion 9 passes through its lower portion and is connected and supported to the base portion 8 so as to be rotatable about a rotation axis X (also referred to as a pivot axis) extending in the left-right direction. Thereby, the upper half of the backrest surface 5S is configured to be tiltable with respect to the lower half. In the present embodiment, the headrest 6 is fixed to the upper portion of the movable portion 9.

[0045] In the seat 1, the upper half of the backrest surface 5S is configured to be tiltable with respect to the lower half, and the central portion of the seat back 5 can be bent. Therefore, the seat back 5 of the seat 1 is also referred to as a center-folded seat back. Hereinafter, the position of the movable portion 9 when the upper portion of the movable portion 9 is tilted most rearward is described as the upright position (also referred to as the reclined position), and the movable portion 9 rotates about the rotation axis X from the upright position, and the position of the movable portion 9 when its upper portion is tilted most forward is described as the forward tilt position.

[0046] The seat cushion 4 includes a seat cushion frame (not shown) that forms a skeleton, a pad member (not shown) supported by the seat cushion frame, and a skin material (not shown) that covers at least a part of the surface of the pad member. The pad member constituting the seat cushion 4 is formed of an elastic cushion material such as polyurethane foam, and the skin material covering the pad member is preferably formed of genuine leather, synthetic leather, fabric, or the like. The seat cushion 4 is configured by covering the seat cushion frame with the pad member and the skin material.

[0047] The seat back 5 includes a seat back frame 10 that forms a skeleton, a pad member (not shown) supported by the seat back frame 10, and a skin material (not shown) that covers at least a part of the surface of the pad member. The pad member may be configured such that the upper half constituting the movable portion 9 and the lower half constituting the base portion 8 are separate bodies, or the upper half constituting the movable portion 9 and the lower half constituting the base portion 8 may be integrally configured so that the seat back 5 can be easily bent. Similarly, the skin material may be configured such that the upper half constituting the movable portion 9 and the lower half constituting the base portion 8 are separate bodies.

[0048] Next, the details of the seat back frame 10 will be described.

[0049] As shown in FIG. 2, the seat back frame 10 includes a base frame 11 that forms the skeleton of the base portion 8, and a movable frame 12 that forms the skeleton of the movable portion 9 and is rotatably coupled to the base frame 11 about the rotation axis X. At the lower part of the base frame 11, a reclining shaft 13 to which the seat cushion frame is connected is provided.

[0050] <Base frame> As shown in FIGS. 2, 3(A), and 3(B), the base frame 11 has a rectangular frame shape including a pair of left and right base side members 14, a base upper member 15, and a base lower member 16. The base side members 14 each extend in the vertical direction and are arranged at intervals in the left and right directions. The base upper member 15 extends in the left and right directions and connects the upper portions (the upper ends in this embodiment) of the two base side members 14. The base lower member 16 also extends in the left and right directions and connects the lower portions of the two base side members 14. Thereby, the base frame 11 forms a rectangular frame body when viewed from the front.

[0051] In this embodiment, as shown in FIG. 3(B), the base frame 11 includes two base middle members 17 that connect the central portions in the vertical direction of the left base side member 14 and the central portions in the vertical direction of the right base side member 14. The two base middle members 17 are arranged at intervals in the vertical direction. Hereinafter, the upper base middle member 17 will be referred to as the upper middle member 17U, and the lower base middle member 17 will be referred to as the lower middle member 17D. The central portion in the left and right direction of the upper middle member 17U and the central portion in the left and right direction of the base upper member 15 are connected by a central member 18.

[0052] Further, each of the base side members 14 is provided with a plate-like side edge portion 19 that extends from the rear end inward of the seat and has a front-facing surface. The front surface of the side edge portion 19 and the wall surface inside the seat of the base side member 14 are connected at a substantially right angle in top view.

[0053] As shown in FIGS. 4, 5(A), and 5(B), the base frame 11 includes a front panel 20 (also referred to as a front member or a front frame) and a rear panel 21 (also referred to as a rear member or a rear frame).

[0054] As shown in FIG. 5(A), the front panel 20 has a rectangular frame shape formed by a bent sheet metal member. The front panel 20 constitutes the seat side of the base frame 11 and receives the load of the occupant. As shown in FIG. 5(B), the rear panel 21 also has a rectangular frame shape formed by a bent sheet metal member. The rear panel 21 is disposed at a position facing the front panel 20 and constitutes the side of the base frame 11 away from the seat occupant.

[0055] As shown in FIG. 6, the rear panel 21 has an outer frame portion 21A that constitutes the outer surface of the seat of the base side member 14, a first extension portion 21B that extends from the front edge of the outer frame portion 21A inward of the seat, and a second extension portion 21C that extends from the rear edge of the outer frame portion 21A inward of the seat. The front panel 20 has an inner frame portion 20A that constitutes the inner portion of the seat of the base side member 14, a third extension portion 20B that extends from the front edge of the inner frame portion 20A outward of the seat, and a fourth extension portion 20C that extends from the front edge of the inner frame portion 20A inward of the seat. The inner frame portion 20A and the outer frame portion 21A face each other and are disposed at a spaced-apart position. The first extension portion 21B and the third extension portion 20B are overlapped, and the second extension portion 21C and the fourth extension portion 20C are overlapped and joined (by welding in this embodiment), whereby the rear panel 21 is joined to the front panel 20 at the edge. The rear panel 21 cooperates with the front panel 20 to form a closed cross-sectional structure P. As a result, a cavity 22 is formed in the base frame 11, and the base frame 11 is configured to be hollow.

[0056] In addition, in the present embodiment, the second extending portion 21C connects the left and right outer frame portions 21A in part, and the fourth extending portion 20C also connects the inner frame portion 20A in part. The base middle member 17 is formed by the second extending portion 21C and the fourth extending portion 20C being overlapped and joined. The central member 18 (specifically, the vertical center portion of the central member 18) is mainly composed of only the rear panel 21.

[0057] <Airbag module> As shown in FIGS. 3(A) and 3(B), two airbag modules 24 are coupled to the base frame 11. One airbag module 24 is coupled to the outer side (left side in the present embodiment) of the side surface of the base frame 11 (base side member 14). Thus, the airbag module 24 coupled to the outer side of the base frame 11 constitutes the outer airbag module 24L.

[0058] The other airbag module 24 is coupled to the inner side (right side in the present embodiment) of the base frame 11 (base side member 14). Thus, the airbag module 24 coupled to the inner side of the base frame 11 constitutes the inner airbag module 24R including the near-side airbag.

[0059] The outer airbag module 24L and the inner airbag module 24R are respectively located on the left and right sides of the movable frame 12 and are coupled to the outer side surface of the seat of the rear panel 21. Thus, the airbag modules 24 are provided on both the left and right outer side surfaces of the seat of the base frame 11. Therefore, the airbag 25 can be deployed on both sides outside the seat of the seated person, and the safety of the seat 1 is enhanced.

[0060] <Airbag module·bolt hole·access hole> As shown in FIG. 6, the airbag module 24 includes an airbag 25, an inflater 26 that inflates the airbag 25 by introducing gas into the airbag 25, and a case 27 that houses the airbag 25 and the inflater 26. A retainer 28 is provided on the side surface of the airbag module 24 on the inner side of the seat. The inflater 26 is provided with a plurality of stud bolts 29. The stud bolts 29 penetrate through the bottom wall of the case 27 located on the inner side of the seat and the retainer 28, and protrude to the inner side of the seat.

[0061] As shown in FIGS. 4 and 5(B), fastening holes 30 for passing the stud bolts 29 are provided in the outer frame portion 21A of the rear panel 21. The stud bolts 29 are respectively inserted into the corresponding fastening holes 30, and nuts 31 are coupled thereto, whereby the airbag module 24 is fastened to the side surface of the base side member 14 on the outer side of the seat (that is, the side surface of the rear panel 21 on the outer side of the seat). Hereinafter, the joint portion of the rear panel 21 with the outer airbag module 24L on the outer side will be referred to as a rear joint portion 32. In the present embodiment, the rear joint portion 32 is constituted by the fastening holes 30.

[0062] As shown in FIGS. 2 and 5(A), the front panel 20 is provided with access holes 33 which are through holes for accessing the fastening holes 30 from the inner side of the seat.

[0063] As shown in FIG. 4, at least one (preferably both) of the width in the front-rear direction and the width in the vertical direction of the access hole 33 is configured to be larger than that of the fastening hole 30, and the area of the opening portion of the access hole 33 is formed to be larger than the area of the opening portion of the fastening hole 30. Thereby, since an operator can easily pass the nut 31 and tools through the access hole 33, the assembling workability of the airbag module 24 can be improved.

[0064] In this embodiment, two stud bolts 29 are provided for each airbag module 24. Further, four fastening holes 30 are arranged vertically side by side on one base side member 14 so that the airbag module 24 can be assembled at two vertical positions (hereinafter, the upper position and the lower position). Hereinafter, the four fastening holes 30 will be described in order from the top as the first fastening hole 30A, the second fastening hole 30B, the third fastening hole 30C, and the fourth fastening hole 30D.

[0065] When the stud bolts 29 are respectively inserted into and fastened to the first fastening hole 30A and the third fastening hole 30C, the airbag module 24 is assembled to the base side member 14 at the upper position. On the other hand, when the stud bolts 29 are respectively inserted into and fastened to the second fastening hole 30B and the fourth fastening hole 30D, the airbag module 24 is assembled to the base side member 14 at the lower position.

[0066] Therefore, two access holes 33 are provided in the inner frame portion 20A of the front panel 20, namely, an upper access hole 33A disposed inside the seat of the first fastening hole 30A and the second fastening hole 30B, and a lower access hole 33B disposed inside the seat of the third fastening hole 30C and the fourth fastening hole 30D. The upper access hole 33A and the lower access hole 33B are formed vertically side by side on the front panel 20.

[0067] As shown in FIG. 4, the upper access hole 33A is formed so as to overlap the first fastening hole 30A and the second fastening hole 30B in a side view. The upper edge of the upper access hole 33A is located above the upper edge of the first fastening hole 30A, and the lower edge of the upper access hole 33A is located below the lower edge of the second fastening hole 30B.

[0068] The lower access hole 33B is formed so as to overlap the third fastening hole 30C and the fourth fastening hole 30D in a side view. The upper edge of the lower access hole 33B is located above the upper edge of the third fastening hole 30C, and the lower edge of the lower access hole 33B is located below the lower edge of the fourth fastening hole 30D.

[0069] <Bead> As shown in FIGS. 2 and 5(A), a bead 35 is provided in the vicinity of the access hole 33 of the front panel 20. The bead 35 functions as a rigidity improving portion that increases the rigidity of the vicinity of the access hole 33 of the front panel 20. In the present embodiment, the bead 35 is provided at a corner portion 36 which is behind the two access holes 33 and is a connecting portion between the side edge portion 19 and the base side member 14 (inner frame portion 20A). The bead 35 forms a protruding ridge at the corner portion 36. The bead 35 may be formed by being pushed out (bent) in a direction in which the front panel 20 is inclined forward toward the inside of the sheet at the corner portion 36.

[0070] FIG. 7(A) shows an enlarged view of the vicinity of the bead 35 of the front panel 20. As shown in FIG. 7(A), one bead 35 is provided at the corner portion 36 of the front panel 20 so as to extend in the vertical direction. The upper end of the bead 35 is located below the upper end of the upper access hole 33A. The lower end of the bead 35 is located below the lower end of the lower access hole 33B.

[0071] However, the number, shape, and arrangement of the beads 35 are not limited to the mode shown in FIG. 7(A). FIGS. 7(B) to (D) show modification examples of the number, shape, and arrangement of the beads 35.

[0072] In the example shown in FIG. 7(B), one bead 35 is provided at the corner portion 36 so as to extend in the vertical direction. The upper end of the bead 35 is located above the upper end of the upper access hole 33A. The lower end of the bead 35 is located below the lower end of the lower access hole 33B.

[0073] In the example shown in FIG. 7(C), one bead 35 is provided at the corner portion 36 so as to extend in the vertical direction. The upper end of the bead 35 is located above the upper end of the upper access hole 33A. The lower end of the bead 35 is located above the lower end of the lower access hole 33B.

[0074] In the example shown in FIG. 7(D), a plurality of beads 35 are arranged side by side in the vertical direction. The beads 35 may be arranged at equal intervals in the vertical direction. The upper end of the bead 35 located at the uppermost side is positioned above the upper access hole 33A. The lower end of the bead 35 located at the lowermost side is positioned below the lower access hole 33B.

[0075] In FIGS. 7(A) to 7(D), the beads 35 provided on the outer vehicle base side member 14 are shown, but beads 35 having shapes corresponding to the respective examples may be provided on the inner vehicle base side member 14. Note that the beads 35 provided on the outer vehicle base side member 14 and the beads 35 provided on the inner vehicle base side member 14 may have the same (symmetrical) shape, or one may be formed to be longer than the other. Also, in the example shown in FIG. 7(D), the number of beads 35 provided on the outer vehicle base side member 14 and the number of beads 35 provided on the inner vehicle base side member 14 may be different.

[0076] As shown in FIG. 6, the front panel 20 may be coupled to the rear panel 21 at a position avoiding the beads 35. Thereby, the front panel 20 and the rear panel 21 can be easily coupled. Note that for the coupling between the front panel 20 and the rear panel 21, various known methods such as joining by laser welding or the like and bolt fastening can be employed.

[0077] On the other hand, the front panel 20 may be coupled to the rear panel 21 at a position overlapping the beads 35. Thereby, the front panel 20 can be coupled to the rear panel 21 at a highly rigid portion.

[0078] <Movable frame> As shown in FIGS. 2, 8, and 9, the movable frame 12 includes a pair of left and right movable side members 38 and a movable upper member 39. The movable side members 38 are spaced apart left and right and each extend in the vertical direction. The movable upper member 39 extends in the horizontal direction and connects the upper portions of the two movable side members 38. Each of the movable side members 38 is rotatably coupled to the base side member 14 about a rotation axis X via a rotation bracket 40 (also referred to as an attachment member) at its lower end. Thus, as can be understood from FIGS. 2 and 9, the movable frame 12 is rotatably coupled (i.e., tiltably) to the base frame 11 about the rotation axis X.

[0079] In this embodiment, the movable frame 12 is formed of a bent pipe material, but is not limited to this mode and may be formed of one or more sheet metal members.

[0080] Specifically, as shown in FIG. 9, each of the movable side members 38 has a movable member side portion 41 that constitutes the lower portion and a movable member shoulder portion 42 that constitutes the central and upper portions. The movable member side portions 41 each extend in the vertical direction. Each of the movable member side portions 41 is rotatably connected about the rotation axis X via a rotation bracket 40 inside the seat of the base side member 14 at its lower end. The movable member shoulder portions 42 are each connected to the upper end of the movable member side portion 41. The movable member shoulder portions 42 extend upwardly and obliquely inward from the upper end of the movable member side portion 41, then bend upwardly at the movable member bent portion 43, and further extend upwardly. The movable member shoulder portion 42 of the left movable side member 38 is connected to the left end of the movable upper member 39 at its upper end, and the movable member shoulder portion 42 of the right movable side member 38 is connected to the right end of the movable upper member 39 at its upper end.

[0081] In addition, in the present embodiment, as shown in FIG. 2, an auxiliary member 44 connected to the left and right movable side members 38 is provided on the movable frame 12. The auxiliary member 44 is formed of a bent wire and is coupled to the corresponding movable side member 38 at both the left and right ends thereof.

[0082] As shown in FIG. 10, the rotation bracket 40 is fixed to the base frame 11 (specifically, the base side member 14), and the movable frame 12 is rotatably connected to the base frame 11 (base side member 14) about the rotation axis X (also referred to as rotatable).

[0083] The rotation bracket 40 is formed of a bent sheet metal member. The rotation bracket 40 includes a rotation bracket front portion 45 coupled to the inner side surface of the sheet of the base side member 14 on one side of the left and right, and a rotation bracket rear portion 46 extending inward from the rear edge of the rotation bracket front portion 45 and coupled to the front surface of the side edge portion 19.

[0084] The rotation bracket front portion 45 has a flat plate portion 45A and a bulging portion 45B bulging inward of the sheet. The plate portion 45A is disposed along the inner side surface of the sheet of the front panel 20 constituting the base side member 14. The bulging portion 45B is circular in side view. The bulging portion 45B is spaced apart from the inner side surface of the sheet of the front panel 20 constituting the base side member 14. Through holes 48 (see FIG. 9) are provided at the lower ends of the movable side members 38, respectively. A pin 49 (see FIG. 10) that passes through the through hole 48 and extends in the left - right direction is fixed to the bulging portion 45B. Thereby, the movable side member 38 is rotatably coupled to the pin 49 about the rotation axis X. Thereby, the movable side members 38 are each rotatably connected to the inner side surface of the sheet of the bulging portion 45B about the rotation axis X.

[0085] As shown in FIG. 9, bolt holes 50 are provided in the front portion 45 and the rear portion 46 of the rotating bracket, respectively. Hereinafter, the bolt hole 50 provided in the front portion 45 of the rotating bracket will be referred to as the front bolt hole 50A, and the bolt hole 50 provided in the rear portion 46 of the rotating bracket will be referred to as the rear bolt hole 50B.

[0086] On the wall constituting the inner side of the seat of the base side member 14 of the front panel 20, a stud bolt 52 protruding inward of the seat is provided. As shown in FIGS. 5(A) and 5(B), in the present embodiment, a first through hole 53 penetrating the wall is provided in the wall constituting the inner side of the seat of the base side member 14 of the front panel 20. The stud bolt 52 is inserted into the first through hole 53 and fixed to the front panel 20. A second through hole 54 penetrating in the plate thickness direction (front-rear direction) is provided in a portion of the first through hole 53 located on the inner side of the seat of the side edge portion 19. In the present embodiment, the second through hole 54 penetrates the front panel 20 and the rear panel 21, respectively. However, the second through hole 54 may be configured to penetrate only the front panel 20.

[0087] The stud bolt 52 is inserted into the front bolt hole 50A and the first through hole 53, and a nut 55 is coupled to the stud bolt 52, whereby the front portion 45 of the rotating bracket is fastened to the side surface on the inner side of the seat of the base side member 14. A bolt 56 is inserted into the rear bolt hole 50B and the second through hole 54, and a nut 57 is coupled thereto, whereby the rear portion 46 of the rotating bracket is fastened to the front surface of the side edge portion 19. Thereby, the rotating bracket 40 is fastened and fixed to the inner surface on the inner side of the seat of the front panel 20 and the side edge portion 19.

[0088] Hereinafter, the first through hole 53 and the second through hole 54, which are the coupling portions of the front panel 20 with the rotating bracket 40, will be collectively referred to as the front coupling portion 58. The rotating bracket 40 is fastened to the front coupling portion 58 of the front panel 20, and the movable frame 12 is rotatably coupled to the front coupling portion 58 via the rotating bracket 40. Two front coupling portions 58 are provided on the front panel 20.

[0089] As shown in FIG. 2, the rotation bracket 40 is located between the outer airbag module 24L and the inner airbag module 24R. The rotation bracket 40 is located above the rear coupling portion 32. As a result, both of the two front coupling portions 58, which are the coupling portions with the movable frame 12 of the front panel 20, are located above the rear coupling portion 32. As shown in FIG. 10, the front coupling portions 58 are respectively provided in front of and behind the rear coupling portion 32. In this way, since the rotation bracket 40 is coupled to the front panel 20 before and after the rear coupling portion 32, the movable frame 12 can be firmly coupled to the front panel 20.

[0090] As shown in FIGS. 9 and 10, the rotation bracket 40 includes a flange portion 60. The flange portion 60 is formed in a plate shape extending forward from the lower edge of the rear portion 46 of the rotation bracket. The flange portion 60 is formed in a rectangular plate shape having a surface facing in the vertical direction. As shown in FIG. 10, an insertion hole 62 penetrating in the vertical direction is provided at substantially the center in the front-rear, left-right directions of the flange portion 60. In the present embodiment, the insertion hole 62 is circular in top view.

[0091] As shown in FIG. 9, the flange portion 60 is located between the two front coupling portions 58 in the front-rear direction. That is, the front coupling portions 58 are arranged in front of and behind the flange portion 60.

[0092] <Headrest frame> As shown in FIG. 2, a headrest frame 64 is coupled to the rear surface of the movable frame 12. The headrest frame 64 is a frame for supporting or constituting the headrest 6, and in the present embodiment, it is provided for supporting the headrest 6.

[0093] As shown in FIGS. 2 and 3(A), the headrest frame 64 includes a pair of left and right vertical portions 65 spaced apart left and right, and a horizontal portion 66 extending left and right and connecting the upper edges of the vertical portions 65. The lower ends of the vertical portions 65 are respectively coupled to the movable member bending portions 43. Thereby, the headrest frame 64 is fixed to the movable side member 38.

[0094] Each of the vertical portions 65 has a headrest side portion 68 and a headrest shoulder portion 69. The headrest side portion 68 is coupled to the movable side member 38 at its end and extends upward. The headrest side portion 68 may be coupled (welded) to the movable member bending portion 43. The headrest shoulder portion 69 is coupled to the upper end of the headrest side portion 68 at its end. The headrest shoulder portion 69 extends upwardly inclined inwardly of the seat from the upper end of the headrest side portion 68, bends upwardly at the headrest bending portion 70, and further extends upwardly.

[0095] In the present embodiment, the headrest frame 64 is constituted by a bent pipe material, but is not limited to this aspect, and may be constituted by one or more sheet metal members.

[0096] The headrest 6 is fixed to the upper part of the headrest frame 64. The headrest 6 may be constituted by a plate-like member (not shown) facing in the front-rear direction, a pad member (not shown) provided on the front surface of the plate-like member, and a skin material (not shown) covering the front surface of the pad member. By fixing the plate-like member to the headrest frame 64 at the rear surface, the headrest 6 may be coupled to the upper front surface of the headrest frame 64.

[0097] <Pressure-receiving member> As shown in Fig. 2, the seat back frame 10 is provided with a pressure-receiving member 72 for supporting the load of the seated person. The pressure-receiving member 72 includes a lower pressure-receiving member 73 provided on the base frame 11 and an upper pressure-receiving member 74 provided on the movable frame 12. The lower pressure-receiving member 73 is supported by the base frame 11, and the upper pressure-receiving member 74 is mainly supported by the movable frame 12. The upper pressure-receiving member 74 is arranged above the lower pressure-receiving member 73 in a front view.

[0098] <Lower pressure-receiving member> The lower pressure-receiving member 73 is arranged behind the lower half of the back of the seated person and supports the load of the lower half of the back of the seated person. As shown in Fig. 2, the lower pressure-receiving member 73 is composed of a plate-shaped member having a flat plate shape. The lower pressure-receiving member 73 may be composed of a resin plate-shaped member, or may be composed of a metal plate material or the like.

[0099] As shown in Fig. 3(A), the lower pressure-receiving member 73 includes a lower main portion 76 having a front surface facing the front-rear direction, and a pair of left and right lower side portions 77 provided at the left and right edges of the lower main portion 76, respectively. The lower main portion 76 has a rectangular shape extending in the vertical direction in a front view. Each of the lower side portions 77 is connected to the edge portion outside the seat of the lower main portion 76. The lower side portion 77 has a rectangular shape that is notched in a triangular shape at the upper end outside the seat.

[0100] As shown in Figs. 2 and 3(A), the lower pressure-receiving member 73 is arranged between the left base side member 14 and the right base side member 14. The lower pressure-receiving member 73 is supported by the left base side member 14 and the right base side member 14 via a lower erection member 79.

[0101] The lower erection member 79 is composed of a bent metal rod-shaped member (a round rod in this embodiment). Note that the lower erection member 79 may be composed of a metal pipe material.

[0102] As shown in FIG. 9, the lower-mounted member 79 has a pair of left and right latching portions 80 and a connecting portion 81 that extends in the left-right direction and connects the lower ends of the latching portions 80. The latching portion 80 has an outer vertical portion 80A that extends upward from the outer end of the seat of the connecting portion 81, a lower horizontal portion 80B that extends inward of the seat from the outer vertical portion 80A, an inner vertical portion 80C that extends upward from the inner end of the seat of the lower horizontal portion 80B, and an upper horizontal portion 80D that extends outward of the seat from the inner vertical portion 80C. At the outer end of the seat of the upper horizontal portion 80D, there are provided retaining portions 80E that extend downward toward the outside of the seat, bend at the extending ends thereof, and extend downward. As shown in FIG. 2, a hook 81A is provided on the connecting portion 81, and the hook 81A is hooked and fixed to an appropriate position of the base lower member 16. Thereby, the connecting portion 81 is connected to the base lower member 16 (see FIG. 2).

[0103] As shown in FIG. 9, the retaining portion 80E of the lower-mounted member 79 is inserted into the insertion hole 62 of the flange portion 60. That is, the one end side of the lower-mounted member 79 is prevented from falling off from the insertion hole 62, and the one end side of the lower-mounted member 79 is coupled to the flange portion 60. Thereby, the lower-mounted member 79 can be coupled to the rotation bracket 40 by a simple method. The flange portion 60 and the insertion hole 62 provided in the flange portion 60 constitute a mounting portion 82 for mounting one end of the lower-mounted member 79.

[0104] In this way, since the member for connecting the movable frame 12 and the base frame 11 and the member for attaching the lower-mounted member 79 to the base frame 11 can be constituted by a single rotation bracket 40 (attachment member), the number of parts of the seat 1 can be reduced without separately providing a member for coupling the lower-mounted member 79 to the base frame 11.

[0105] Also, one end of the lower-mounted member 79 is coupled to the flange portion 60 of the rotation bracket 40. Therefore, the rigidity of the portion of the rotation bracket 40 to which the lower-mounted member 79 is attached can be increased.

[0106] Further, the front coupling portions 58 are provided in front of and behind the mounting portion 82, respectively. Therefore, compared with the case where the front coupling portions 58 are provided only on one side of the front and rear, the rotation bracket 40 can be firmly coupled to the front panel 20, and the lower installation member 79 can be stably supported by the front panel 20.

[0107] A plurality of hooks (not shown) that are hooked on the lower installation member 79 are provided on the rear surface of the lower pressure receiving member 73. By hooking the hooks on the lower installation member 79, the lower pressure receiving member 73 is coupled to the lower installation member 79. Thereby, the lower pressure receiving member 73 is coupled to each of the base side members 14 via the lower installation member 79.

[0108] <Upper pressure receiving member> The upper pressure receiving member 74 is disposed behind the upper part of the back of the seated person and supports the load on the upper part of the back of the seated person. As shown in FIG. 2, the upper pressure receiving member 74 is also constituted by a plate-like member like the lower pressure receiving member 73. The upper pressure receiving member 74 may be constituted by a resin plate-like member, or may be constituted by a metal plate material or the like.

[0109] As shown in FIG. 3(A), the upper pressure receiving member 74 includes a flat upper main portion 84 having a front surface facing in the front-rear direction, and a pair of left and right upper side portions 85 provided on the left and right edges of the upper main portion 84, respectively. As shown in FIG. 2, each of the upper side portions 85 has a flat plate shape, is connected to the edge portion outside the seat (that is, the left and right side edges) of the upper main portion 84, and extends forward toward the outside of the seat. Thereby, the upper pressure receiving member 74 has a shape along the back of the seated person.

[0110] As shown in FIGS. 2 and 3(A), an upper installation member 87 for coupling the upper pressure receiving member 74 to the movable side member 38 is provided on each of the movable side members 38.

[0111] As shown in Fig. 9, the upper installation member 87 is composed of a pair of left and right side frames 88. The side frame 88 is composed of a bent metal rod-shaped member (round bar in this embodiment). Note that the side frame 88 may be composed of a metal pipe material.

[0112] The side frame 88 has an upper vertical portion 88A extending in the vertical direction, an inclined portion 88B inclined downward from the lower end of the upper vertical portion 88A toward the inside of the seat, a lower vertical portion 88C extending downward from the lower end of the inclined portion 88B, and a lower horizontal portion 88D extending from the lower end of the lower vertical portion 88C toward the outside of the seat.

[0113] Each of the movable side members 38 is provided with a mounting bracket 90 for mounting the upper installation member 87.

[0114] The mounting bracket 90 is at the central portion of the movable side member 38, and more specifically, is fixed to the upper portion of the movable member side portion 41. In this embodiment, the mounting bracket 90 is composed of a bent sheet metal member and is fixed to the upper portion of the movable member side portion 41 by welding.

[0115] The mounting bracket 90, similar to the lower installation member 79, is provided with a flange portion 91. The flange portion 91 has a plate shape with a main surface facing in the vertical direction. The flange portion 91 is provided with a mounting hole 92 penetrating in the vertical direction. The upper end of the upper vertical portion 88A of the upper installation member 87 is inserted into the mounting hole 92. Thereby, the upper installation member 87 is mounted on the movable side member 38 via the mounting bracket 90. That is, the mounting bracket 90 constitutes a portion where the upper installation member 87 and the movable frame 12 are connected.

[0116] On the upper edge of the upper vertical portion 88A, a bent portion 93 bent in the horizontal direction is provided to prevent the upper vertical portion 88A from coming out of the mounting hole 92. Thereby, the side frames 88 are respectively coupled to the movable side members 38, and the upper installation member 87 is coupled to and supported by the movable side members 38.

[0117] A plurality of hooks (not shown) that are hooked to the upper erection member 87 are provided on the rear surface of the upper pressure receiving member 74. When the hooks are hooked to the upper erection member 87, the upper pressure receiving member 74 is coupled to the front surface of the upper erection member 87 and is coupled and supported on the front side of the upper erection member 87. The upper pressure receiving member 74 is coupled to each of the movable side members 38 via the upper erection member 87.

[0118] In the present embodiment, as shown in FIG. 9, a cylindrical tubular member 94 (also referred to as a collar) is provided on the lower erection member 79. The upper erection member 87 is inserted into the tubular member 94 together with the lower erection member 79 at the lower edge (lower horizontal portion 88D) and is coupled to the tubular member 94. Thereby, the upper pressure receiving member 74 is connected to the lower erection member 79 so as to be tiltable in the front-rear direction. That is, the tubular member 94 functions as a connecting portion between the lower erection member 79 and the upper pressure receiving member 74. In order to facilitate the assembly of the tubular member 94, one slit (not shown) extending in the left-right direction may be provided on the rear surface of the tubular member 94. The tubular member 94 may be made of metal or may be made of resin or the like.

[0119] As shown in FIG. 8, when the movable frame 12 rotates about the rotation axis X and tilts forward, a load that tries to tilt the upper pressure receiving member 74 forward is applied via the upper erection member 87. Since the upper pressure receiving member 74 is tiltably connected to the lower erection member 79 via the tubular member 94, the upper pressure receiving member 74 rotates following the tilt of the movable frame 12. Therefore, by connecting the lower erection member 79 and the upper erection member 87 with the tubular member 94 while reducing the influence of the tilt of the movable frame 12, the upper pressure receiving member 74 can be stably supported by the seat back frame 10.

[0120] One end of the lower erection member 79 is inserted into the insertion hole 62 of the flange portion 60 and is prevented from coming off. Therefore, the lower erection member 79 is supported by the flange portion 60 so as to be slidable in the penetrating direction of the insertion hole 62. Therefore, when the upper erection member 87 is pulled upward, the lower erection member 79 can be moved following it.

[0121] As shown in FIG. 3(A), the upper side portion 85 on the left side of the upper pressure receiving member 74 and the movable member shoulder portion 42 on the left side of the movable side member 38 are arranged at positions aligned in the vertical direction in a front view. Similarly, the upper side portion 85 on the right side of the upper pressure receiving member 74 and the movable member shoulder portion 42 on the right side of the movable side member 38 are arranged at positions aligned in the vertical direction in a front view.

[0122] As a result, the upper main portion 84 is arranged behind the center of the back of the seated person, and the upper side portion 85 is arranged at a position along the left and right side portions of the back of the seated person. That is, the upper pressure receiving member 74 can be arranged along the back of the seated person.

[0123] In the present embodiment, as shown in FIG. 3(A), notch portions 95 notched upward are provided at the lower edges of the upper side portions 85, respectively. As a result, when the movable portion 9 is in the upright position, the rotation bracket 40 can be visually recognized from the front by the operator performing the assembly, so that the assembly workability of the seat 1 is improved.

[0124] In FIG. 11, a first virtual plane S1 along the front surface of the lower main portion 76 is shown by a two-dot chain line. As shown in FIG. 11, the cylindrical member 94 is located behind the first virtual plane S1. That is, when viewed in the direction along the front surface of the lower main portion 76, the cylindrical member 94 is arranged behind the lower main portion 76, and the lower erection member 79 and the upper pressure receiving member 74 are connected behind the lower main portion 76. Thereby, it is possible to prevent the seated person from feeling a foreign object due to the connection portion between the lower erection member 79 and the upper pressure receiving member 74.

[0125] In FIG. 11, a second virtual plane S2 along the front surface of the upper main portion 84 is shown by a one-dot chain line. As shown in FIG. 11, the cylindrical member 94 is located behind the second virtual plane S2. That is, when viewed in the direction along the front surface of the upper main portion 84, the cylindrical member 94 is arranged behind the upper main portion 84, and the lower erection member 79 and the upper pressure receiving member 74 are connected behind the upper main portion 84. Thereby, it is possible to prevent the seated person from feeling a foreign object due to the connection portion between the lower erection member 79 and the upper pressure receiving member 74.

[0126] Note that the lower pressure receiving member 73 is not coupled to the movable frame 12 and may be coupled to and supported only by the base frame 11. The upper pressure receiving member 74 is not coupled to the base frame 11 and may be coupled to and supported only by the movable frame 12. Thereby, the lower pressure receiving member 73 is rotatable with respect to the movable frame 12, and the upper pressure receiving member 74 is rotatable with respect to the base frame 11. Thereby, a pressure receiving member 72 that can further reduce the influence of the tilting of the movable frame 12 can be configured.

[0127] <Actuator> As shown in FIGS. 2 and 8, the seat back 5 includes an actuator 98 for tilting (rotating) the movable part 9. The actuator 98 is provided between the base frame 11 and the movable frame 12.

[0128] As shown in FIG. 8, the actuator 98 includes a motor 98A, a lead screw 98B, and a gear box 98C that converts the rotation of the motor 98A into a linear motion of the lead screw 98B. The gear box 98C includes a gear and a housing that houses the gear. The housing has a through hole through which the lead screw 98B passes. When the output shaft of the motor 98A rotates, one end of the lead screw 98B protrudes or retracts and moves in a direction approaching or separating from the housing. In the present embodiment, the axial direction of the output shaft of the motor 98A and the axial direction of the lead screw 98B are configured to be orthogonal to each other.

[0129] A connecting member 100 is fixed to the movable upper member 39, and the lead screw 98B is rotatably connected to the connecting member 100 at its end about an axis Y extending in the left-right direction. Thereby, the actuator 98 is rotatably connected to the movable upper member 39 at the end of the lead screw 98B (the upper end in FIG. 2) about the left-right direction as the axis Y.

[0130] Since the connecting member 100 is fixed to the movable upper member 39, the actuator 98 is connected to the portion between the two movable member bending portions 43 of the movable frame 12. Further, as shown in FIG. 3(A), the connection portion between the actuator 98 and the movable frame 12 is located between the headrest bending portions 70 in a front view.

[0131] As shown in FIG. 8, the gear box 98C is rotatably connected to the first connecting bracket 102 about the axis Z in the left - right direction. The first connecting bracket 102 is fixed to the second connecting bracket 103, and the second connecting bracket 103 is fixed to the base upper member 15. Thereby, the gear box 98C is rotatably connected to the base upper member 15 about the axis Z extending in the left - right direction.

[0132] Thereby, one end of the actuator 98 (corresponding to the end of the gear box 98C) is rotatably connected to the base upper member 15 about the axis Z extending in the left - right direction. The other end of the actuator 98 (corresponding to the lead screw 98B) is rotatably connected to the movable upper member 39 about the axis Y extending in the left - right direction. Thus, the movable side member 38 and the corresponding base side member 14, one end of the actuator 98 and the base upper member 15, and the other end of the actuator 98 and the movable upper member 39 are each rotatably connected about the axes Y and Z extending in the left - right direction. Thereby, the actuator 98 connects the base upper member 15 and the movable upper member 39, and by driving the actuator 98, it is possible to rotate the movable upper member 39 to approach and separate from the base upper member 15.

[0133] In this embodiment, the actuator 98 was configured to move the movable upper member 39 closer to and away from the base upper member 15, but the present invention is not limited to this mode. Specifically, the actuator 98 may be connected to the upper part of the base frame 11 other than the base upper member 15 (specifically, the part above the rotation axis X) and the movable upper member 39, and may be configured to perform at least one of the operations of moving the movable upper member 39 closer to and away from the upper part of the base frame 11.

[0134] When the end of the lead screw 98B moves in the direction of protruding from the gear box 98C by driving the actuator 98, the movable upper member 39 is pushed forward with respect to the base upper member 15. As a result, the movable frame 12 rotates about the rotation axis X with respect to the base frame 11 in a direction of tilting forward with respect to the base frame 11.

[0135] When the end of the lead screw 98B moves in the direction of retracting into the gear box 98C by driving the actuator 98, the movable upper member 39 is pulled toward the side of the base upper member 15. As a result, the movable frame 12 rotates about the rotation axis X with respect to the base frame 11 in a direction of tilting backward with respect to the base frame 11.

[0136] In this way, the actuator 98 tilts the movable frame 12 with respect to the base frame 11 and displaces (specifically, rotationally displaces) the movable part 9 between the forward tilt position and the upright position.

[0137] As shown in FIGS. 2 and 8, at least one of the base frame 11 and the movable frame 12 is provided with a receiving recess 105 for receiving at least a part of the actuator 98. In the present embodiment, the receiving recess 105 is provided at the front surface of the base upper member 15 and at the central portion in the left-right direction thereof. As shown in FIG. 2, the receiving recess 105 is formed as a recess that is recessed rearward (in a direction away from the movable upper member 39) at the front surface of the base upper member 15. At least a part of the actuator 98 (for example, a part of the motor 98A and the lead screw 98B) is received inside the receiving recess 105 in a side view (see FIG. 4).

[0138] The receiving recess 105 is at the front surface of the base upper member 15, where the front panel 20 and the rear panel 21 face each other front and rear, and both are provided at a position where they overlap in the front-rear direction.

[0139] As shown in FIG. 8, the gear box 98C is pivotally supported by the first connection bracket 102. The second connection bracket 103 has a U-shaped cross-section that opens rearward. The second connection bracket 103 is coupled (by welding in the present embodiment) to the upper surface and the front surface (the bottom surface of the receiving recess 105) of the portion of the base upper member 15 where the receiving recess 105 is provided. The first connection bracket 102 is connected to the front surface of the second connection bracket 103.

[0140] The second connection bracket 103 is coupled to a position where the front panel 20 and the rear panel 21 of the seat back frame 10 face each other. Thereby, the actuator 98 is supported via the second connection bracket 103 at a position where the front panel 20 and the rear panel 21 of the seat back frame 10 face each other. Thereby, the actuator 98 can be supported at a portion of the base frame 11 that has high rigidity and is difficult to deform.

[0141] Note that since the connecting member 100 is fixed to the movable upper member 39, the actuator 98 is connected to the movable upper member 39, that is, the portion between the two movable member bent portions 43 of the movable frame 12. Therefore, the connection portion between the actuator 98 and the movable frame 12 can be arranged at a position closer to the center of the seat in the left - right direction. As a result, for example, compared with the case where the actuator 98 is connected to the movable side member 38, the actuator 98 can stably rotate (tilt) the movable frame 12.

[0142] However, specifically, the second connecting bracket 103 is provided at a position biased to either the left or right side in the left - right direction of the receiving recess 105. Therefore, the lead screw 98B is arranged at a position biased to either the left or right side (the outside of the vehicle in this embodiment) in the receiving recess 105. With this arrangement, a sufficient space for accommodating the motor 98A can be secured between the wall surface defining the other side (the inside of the vehicle in this embodiment) in the left - right direction of the receiving recess 105 and the lead screw 98B.

[0143] <Arrangement of members in the upright position and the forward - tilted position> As shown in FIG. 12, when the movable part 9 is in the upright position (when the movable upper member 39 is located at the rearmost position), in a top view, the movable member shoulder part 42 is located behind the rotation bracket 40. Also, at least a part of the movable member shoulder part 42 is located in front of the mounting bracket 90 (the part where the upper - mounted member 87 and the movable frame 12 are connected). However, the entire movable member shoulder part 42 may be located in front of the mounting bracket 90. Also, at least a part of the mounting bracket 90 is located in front of the actuator 98, and preferably the entire mounting bracket 90 is located in front of the actuator 98.

[0144] By configuring in this way, the upright position can be set to an appropriate position where the movable part 9 does not tilt too much forward or backward, and a large - sized seated person can sit down relaxedly.

[0145] In addition, since the mounting bracket 90 is positioned in front of the actuator 98 and the upper pressure receiving member 74 is supported on the front side of the upper erection member 87, the upper pressure receiving member 74 is disposed in front of the actuator 98. Therefore, it is possible to prevent giving a foreign body sensation caused by the actuator 98 to the seated person.

[0146] As shown in FIGS. 13 and 14, when the movable part 9 is in the forward tilt position (when the movable upper member 39 is located at the most forward position), the portion (flange portion 60) where the lower erection member 79 and the seat back frame 10 are connected is located behind the front end of the actuator 98.

[0147] By configuring in this way, the forward tilt position can be set to an appropriate position capable of supporting the back of a relatively small-sized seated person.

[0148] Also, as shown in FIG. 2, when the movable part 9 is in the upright position, the upper main part 84 of the upper pressure receiving member 74 and the left and right upper side parts 85 are each located above the rotation axis X (see also FIG. 4). Thereby, since the upper pressure receiving member 74 can be rotationally moved so that the upper part thereof protrudes forward from the position where the upper part tilts backward due to the forward tilt of the movable frame 12 (see FIG. 14), the upper pressure receiving member 74 can be supported by the movable frame 12 so as to be able to support the back of a small-sized seated person by the rotation of the movable frame 12.

[0149] Note that, as shown in FIG. 14, in both cases where the movable part 9 is in the upright position and the forward tilt position, at least a part of the actuator 98 is located behind the upper pressure receiving member 74. Also, at least a part of the actuator 98 is located behind the headrest frame 64.

[0150] <Method for manufacturing a seat> Next, a method for manufacturing the seat 1 will be described. The method for manufacturing the seat 1 includes a first step of manufacturing the base frame 11, a second step of rotatably assembling the movable frame 12 to the base frame 11, a third step of assembling the upper installation member 87 and the lower installation member 79 to the first installation member and the second installation member respectively, a fourth step of assembling the first installation member and the second installation member, and a fifth step of connecting the actuator 98 to the movable frame 12 and the base frame 11. After the fifth step, the headrest 6, the pad member, and the skin material are sequentially assembled.

[0151] The first step includes a step of manufacturing the front panel 20 and the rear panel 21 by pressing, and a step of connecting the front panel 20 and the rear panel 21 at the peripheral portion to form the base frame 11. The front panel 20 and the rear panel 21 may be connected by welding, or may be connected by fastening using bolts and nuts.

[0152] The first step may preferably include a step of inserting and fixing the stud bolt 52 into the first through hole 53 of the front panel 20. This step may be provided before the step of connecting the front panel 20 and the rear panel 21.

[0153] Also, the first step may preferably include a step of fixing (welding in this embodiment) the second connection bracket 103 to the base upper member 15. This step may be performed after the front panel 20 and the rear panel 21 are connected. In this step, the second connection bracket 103 may be connected (welded) to the upper and lower surfaces of the base upper member 15.

[0154] The second step includes a step of fixing the connecting member 100 to the movable frame 12 by welding or the like, a step of fixing the headrest frame 64 to the movable frame 12, a step of rotatably coupling the movable frame 12 to the rotation bracket 40, and a step of fixing the rotation bracket 40 to the base frame 11. The step of fixing the headrest frame 64 to the movable frame 12 includes a step of coupling (welding in this embodiment) the lower end of the vertical portion 65 to the movable member bending portion 43 of the movable frame 12. The step of rotatably coupling the movable frame 12 to the rotation bracket 40 includes a step of inserting a pin 49 into a through hole 48 provided at the lower end of the movable side member 38 and rotatably connecting the lower end of the movable side frame to the bulging portion 45B of the rotation bracket 40.

[0155] The step of fixing the rotation bracket 40 to the base frame 11 may include a step of positioning the rotation bracket 40 by inserting it into the front bolt hole 50A with respect to the stud bolt 52 provided in the first through hole 53 of the front panel 20, and then, inserting a bolt 56 into the rear bolt hole 50B and the second through hole 54 of the rotation bracket 40 and coupling a nut 57 to couple (fasten in this embodiment) the rear portion 46 of the rotation bracket and the front panel 20. Thereby, after the operator positions the rotation bracket 40 once, the operator can perform the work of coupling the rotation bracket 40 to the base frame 11, so that the ease of assembly work can be improved.

[0156] In addition, the step of fixing the rotation bracket 40 to the base frame 11 may also include a step of coupling the front portion 45 of the rotation bracket and the front panel 20 by attaching a nut 55 to the stud bolt 52.

[0157] The third step may include a step of coupling the hook provided on the rear surface of the upper pressure receiving member 74 to the upper erection member 87 and a step of coupling the hook provided on the rear surface of the lower pressure receiving member 73 to the lower erection member 79. In addition, the third step may include a step of coupling the upper erection member 87 and the lower erection member 79 with a cylindrical member 94.

[0158] The fourth step includes inserting the end of the upper erection member 87 from below into the mounting hole 92 provided in the flange portion 91 of the mounting bracket 90, and inserting the end of the lower erection member 79 from above into the insertion hole 62 provided in the flange portion 60 of the rotation bracket 40. In the step of inserting the end of the upper erection member 87 from below, the operator may insert the end of the upper erection member 87 above the position where it should be arranged after installation (also referred to as overstroking), and then perform the step of inserting the end of the lower erection member 79 into the insertion hole 62 from above. Thereby, after assembling the upper erection member 87, the lower erection member 79 can be attached, so that the assembly workability can be improved.

[0159] The fifth step includes rotatably connecting the first connecting bracket 102 to the gear box 98C, fixing the first connecting bracket 102 to the second connecting bracket 103, and rotatably connecting the end of the lead screw 98B to the connecting member 100. After these three steps, the actuator 98 is connected to the base frame 11 and the movable frame 12.

[0160] Next, the effects of the seat 1 will be described.

[0161] As shown in FIG. 2, the pressure receiving member 72 that supports the load of the seated person includes a lower pressure receiving member 73 provided on the base frame 11 and an upper pressure receiving member 74 provided on the movable frame 12. Therefore, compared with the case where the upper pressure receiving member 74 and the lower pressure receiving member 73 are integrally formed, stress is less likely to occur inside the pressure receiving member 72, and the pressure receiving member 72 is more likely to follow the tilting of the movable portion 9.

[0162] In the present embodiment, the upper erection member 87 is connected to the lower erection member 79 via the cylindrical member 94. Therefore, the upper pressure receiving member 74 is connected to the lower erection member 79 so as to be tiltable in the front-rear direction. Thereby, the upper pressure receiving member 74 can be well supported by the movable frame 12 at the upper and lower portions, and the upper pressure receiving member 74 can be well made to follow the tilting of the movable frame 12.

[0163] The base frame 11 (base upper member 15) is provided with a receiving recess 105 for receiving at least a part of the actuator 98. In this way, by providing the receiving recess 105 recessed rearward in the base upper member 15, a space for accommodating functional components can be formed within the receiving recess 105. Also, the actuator 98 and the base frame 11 are arranged so as to overlap in side view. Therefore, the actuator 98 can be arranged compactly (that is, such that the thickness at the upper part of the seat back frame 10 is reduced).

[0164] The actuator 98 is arranged between the base frame 11 and the movable frame 12. Therefore, by forming the receiving recess 105 to be recessed rearward at the front surface of the base upper member 15, the actuator 98 can be easily accommodated in the receiving recess 105.

[0165] Also, the headrest frame 64 is coupled to the rear surface of the movable frame 12 and is supported by the movable frame 12. Therefore, the connection portion of the headrest frame 64 to the movable frame 12 does not protrude forward of the movable frame 12. Thus, the headrest frame 64 can be connected to the movable frame 12 while preventing a foreign body feeling from being given to the seated person.

[0166] The movable frame 12 is coupled to the front panel 20 via a rotation bracket 40, and the airbag module 24 is coupled to the rear panel 21. With this configuration, compared to the case where the movable frame 12 and the airbag module 24 are provided on the same panel, the movable frame 12 and the airbag module 24 are more likely to be arranged separately. Therefore, it becomes less likely for the rotation of the movable frame 12 to affect the airbag module 24. Also, since the deployment of the airbag 25 can be prevented from being obstructed by the movable frame 12, the airbag 25 can be deployed well, and the safety of the seat 1 is enhanced.

[0167] In the present embodiment, the rotating bracket 40 is located above the coupling portion (rear coupling portion 32) of the airbag module 24 of the rear panel 21. As a result, the coupling portion (front coupling portion 58) of the movable frame 12 of the front panel 20 is located above the coupling portion (rear coupling portion 32) of the airbag module 24 of the rear panel 21. Therefore, since the movable frame 12 and the airbag module 24 are coupled at positions separated in the vertical direction of the base frame 11, it is possible to prevent the deployment of the airbag 25 from being inhibited by the movable frame 12.

[0168] Further, even when the movable part 9 is in either the forward tilt position or the upright position, at least a part of the actuator 98 is located behind the upper pressure receiving member 74. Therefore, it is possible to prevent giving a foreign body sensation to the seated person by the actuator 98 as compared with the case where the entire actuator 98 is disposed in front of the upper pressure receiving member 74.

[0169] With the above, the description of the specific embodiment is finished, but the present invention can be widely modified and implemented without being limited to the above embodiment.

[0170] For example, in the above embodiment, an example in which the pressure receiving member 72 is constituted by the upper pressure receiving member 74 and the lower pressure receiving member 73 is described, but the pressure receiving member 72 may be constituted by two or more plate members arranged substantially parallel to the backrest surface 5S. In that case, the plate members may be coupled to either one of the seat back frame 10 and the movable frame 12 at both ends, and may be rotatably connected to adjacent plate members about a rotation axis X extending in the left-right direction.

[0171] In the above embodiment, the receiving recess 105 is provided in the base frame 11, but it may be provided in the movable frame 12. In that case, the receiving recess 105 may be formed to be recessed forward in the movable upper frame, and at least a part of the lead screw 98B may be accommodated in the receiving recess 105. Alternatively, the receiving recess 105 may be provided in each of the base frame 11 and the movable frame 12. Further, in the above embodiment, an example in which the actuator 98 is received in the receiving recess 105 has been described, but various functional components other than the actuator 98 can be accommodated in the receiving recess 105.

[0172] In the above embodiment, an example in which the present invention is applied to a vehicle seat has been described, but the seat 1 according to the present invention can also be applied to various seats such as aircraft seats and railway seats. Further, not all of the components of the seat 1 shown in the above embodiment are necessarily essential, and they can be appropriately selected.

Explanation of reference numerals

[0173] 1: Seat (an example of a vehicle seat) 5: Seat back 6: Headrest 10: Seat back frame 11: Base frame 12: Movable frame 14: Base side member 15: Base upper member 38: Movable side member 39: Movable upper member 64: Headrest frame 98: Actuator 98A: Motor 98B: Lead screw 98C: Gear box 105: Receiving recess X: Rotation axis (axis) Y: Axis Z: Axis

Claims

1. A vehicle seat in which an upper portion of a seat back can be tilted relative to a lower portion, The seat back frame includes a base frame, a movable frame tiltably connected to the base frame, an actuator having one end connected to the base frame and the other end connected to the movable frame, the actuator performing at least one of an action of moving the one end and the other end closer to and away from each other; At least one of the base frame and the movable frame has a receiving recess that receives at least a portion of the actuator.

2. The base frame includes a pair of left and right base side members and a base upper member connecting upper portions of the base side members, the movable frame includes a pair of left and right movable side members each tiltably connected to the base side member, and a movable upper member connecting upper portions of the movable side members, 2. The vehicle seat according to claim 1, wherein the one end is connected to the base upper member, and the other end is connected to the movable upper member.

3. 3. The vehicle seat of claim 2, wherein the movable side member and the corresponding base side member, the one end of the actuator and the base upper member, and the other end of the actuator and the movable upper member are each rotatably connected about an axis extending in the left-right direction.

4. 3. The vehicle seat according to claim 2, wherein the receiving recess is provided on a front surface of the base upper member.

5. 5. The vehicle seat according to claim 4, wherein the receiving recess is recessed in the base upper member in a direction away from the movable upper member.

6. The actuator includes a motor, a gear box connected to an output shaft of the motor, and a lead screw that slides relative to the gear box when driven by the motor. The gear box is rotatably connected to the base upper member, 6. The vehicle seat according to claim 5, wherein an end of said lead screw is rotatably connected to said movable upper member.

7. an axial direction of the output shaft of the motor and an axial direction of the lead screw are perpendicular to each other; 7. The vehicle seat according to claim 6, wherein the lead screw is provided at a position offset to either the left or right in the receiving recess.

8. A headrest frame is coupled to the movable frame, 8. The vehicle seat according to claim 1, wherein at least a portion of the actuator is located rearward of the headrest frame.

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