JP2020199923A - Vehicle seat - Google Patents

Abstract

To provide a vehicle seat having a constitution that can stand a load which is generated in operation of a seat belt, and that has a center-folding mechanism.SOLUTION: A retractor unit 13 is connected to a lower frame 7. When a vehicle seat 100 is viewed from a direction parallel to a seat width direction in a state where an angle θ formed by an upper frame 8 and the lower frame 7 is the largest within a prescribed range, assuming a first vertical surface S1 passing through a hinge shaft 10, a second vertical surface S2 passing through an outlet 17 and a two-dimentional plane S3 passing through both of the hinge shaft 10 and the outlet 17, then a belt supporting part 13B is arranged between the first vertical plane S1 and the second vertical plane S2 and below the two-dimentional plane S3.SELECTED DRAWING: Figure 10

Description

The present disclosure relates to vehicle seats.

As disclosed in Patent Document 1 below, a vehicle seat having a center folding mechanism is known. The seat back (backrest) is divided into an upper seat back and a lower seat back, and the inclination angle of the upper seat back with respect to the lower seat back is adjusted by the center folding mechanism.

Generally, a seatbelt outlet is provided at the position of the occupant's shoulder. The outlet is not limited to the case where it is provided in the vehicle body, and may be provided integrally with the seat back at the position of the shoulder opening of the seat back (the position away from the vehicle body) (see Patent Documents 2 and 3).

Japanese Unexamined Patent Publication No. 2016-137854 Japanese Unexamined Patent Publication No. 11-321412 Japanese Patent No. 5873189

When the seatbelt outlet is provided in the vehicle body, when the seatbelt is activated, a load is generated by the actuation of the seatbelt, and the load mainly acts on the vehicle body. On the other hand, in the configuration in which the seatbelt outlet is provided at the shoulder opening of the seatback, when the seatbelt operates, a load is generated by the operation of the seatbelt, and the load mainly acts on the seatback. The seat back is required to have a predetermined load capacity.

A vehicle seat provided with a center folding mechanism on the seat back tends to have lower rigidity and strength than a vehicle seat having no center folding mechanism. It is desired that the seatbelt pull-out outlet is provided at the shoulder opening of the seatback and the seatback has a center-folding mechanism so as to have a structure that can more withstand the load generated when the seatbelt is operated.

It is an object of the present disclosure to provide a vehicle seat having a center folding mechanism, which has a structure that can more withstand a load generated when a seatbelt is operated.

The vehicle seat according to the present disclosure includes a seat back, a back frame arranged in the seat back, and having a pair of side frame portions and an upper frame portion connecting the upper portions of the pair of side frame portions. The retractor unit having the belt support portion and arranged inside the vehicle seat and the retractor unit being pulled out upward from the belt support portion and overcoming the upper frame portion from the rear side to the front side. A seat belt, which is arranged in the seat back and is pulled out from the inside of the seat back through an outlet provided at the shoulder opening of the seat back, and each of the pair of the side frame portions has an upper frame and a lower frame. The upper frame and the lower frame are connected to each other via a hinge shaft so as to be relatively rotatable in the front-rear direction of the seat, the retractor unit is connected to the lower frame, and the vehicle seat is further connected. It is provided with a center folding mechanism that can adjust the angle between the upper frame and the lower frame in the front-rear direction of the seat within a predetermined range, and the angle formed between the upper frame and the lower frame is the largest within the predetermined range. When the vehicle seat is viewed from a direction parallel to the seat width direction in this state, the first lead surface passing through the hinge axis, the second lead surface passing through the outlet, and the hinge axis And assuming that a two-dimensional plane passing through both of the outlets is defined, the belt support portion is between the first lead surface and the second lead surface, and is more than the two-dimensional plane. It is located below.

In the vehicle seat, when the vehicle seat is viewed from a direction parallel to the seat width direction, a plane that passes through the hinge axis and is parallel to the horizontal direction is defined as a reference plane. A plane that passes through the hinge axis and is inclined 60 ° upward with respect to the reference plane is defined as an upper side surface, and a plane that passes through the hinge axis and is inclined 30 ° downward with respect to the reference plane is defined as a lower side surface. By definition, the belt support may be located below the upper side surface and above the lower side surface.

In the vehicle seat, the belt support portion may be arranged at a position above the reference plane.

In the vehicle seat, when the vehicle seat is viewed from a direction parallel to the seat width direction, the belt support portion may be arranged at a position that does not overlap with the side frame portion.

In the vehicle seat, the center folding mechanism has a first link member rotatably connected to the upper frame and a second link rotatably connected to both the upper frame and the lower frame. The center folding mechanism has a member, and is rotationally driven by being pivotally supported by a sector gear that integrally rotates with the upper frame and a lower frame about a connection point between the upper frame and the lower frame. At the same time, it is driven by a pinion that meshes with the sector gear, and at least one of the first link member, the second link member, the sector gear, and the pinion is arranged inside the side frame portion. May be good.

In the vehicle seat, the side frame portion has an inner panel portion and an outer panel portion, and at least one of the first link member and the second link member is the inner panel portion and the outer panel portion. It may be rotatably supported by both portions.

According to the above configuration, it is possible to obtain a vehicle seat having a center-folding mechanism, which has a configuration that can withstand a load generated when the seat belt is operated.

It is a perspective view which shows the vehicle seat 100. It is a perspective view which shows the structure of the back side of the back frame 5 provided in the vehicle seat 100. It is a perspective view which shows the structure of the back side such as side frame part 6R. It is a perspective view which shows the structure of the front side such as a side frame part 6R and a center folding mechanism 20. It is a perspective view which shows the structure of the side frame part 6R and the back side of the center folding mechanism 20. It is a perspective view which shows the disassembled state of the center folding mechanism 20. It is a side view which shows the center folding mechanism 20, the upper frame 8 and the lower frame 7, and shows the state which the angle θ formed by the upper frame 8 and the lower frame 7 is the largest within a predetermined range. It is a side view which shows the center folding mechanism 20, the upper frame 8 and the lower frame 7, and shows the state which the angle θ formed by the upper frame 8 and the lower frame 7 is the smallest within a predetermined range. FIG. 8 is a perspective view showing a state in which the upper frame 8 is tilted most forward with respect to the lower frame 7, which corresponds to FIG. It is a side view which shows the hinge shaft 10, the retractor unit 13, the upper frame 8, the lower frame 7, and the like, and is the seat width direction in the state where the angle formed by the upper frame 8 and the lower frame 7 is the largest within a predetermined range. It shows the state of these various members obtained when the vehicle seat 100 is viewed from a direction parallel to the vehicle seat 100. It is a side view which shows the hinge shaft 10, the retractor unit 13, the upper frame 8, the lower frame 7, etc., and is the seat width direction in the state where the angle formed by the upper frame 8 and the lower frame 7 is the smallest within a predetermined range. It shows the state of these various members obtained when the vehicle seat 100 is viewed from a direction parallel to the vehicle seat 100. It is a side view which shows the hinge shaft 10, the retractor unit 13, the upper frame 8, the lower frame 7, etc. about the other structure 1, and the angle formed by the upper frame 8 and the lower frame 7 becomes the largest within a predetermined range. It shows the state of these various members obtained when the vehicle seat is viewed from a direction parallel to the seat width direction in the state of being. It is a side view which shows the hinge shaft 10, the retractor unit 13, the upper frame 8, the lower frame 7, etc. about the other structure 1, and the angle formed by the upper frame 8 and the lower frame 7 becomes the smallest within a predetermined range. It shows the state of these various members obtained when the vehicle seat is viewed from a direction parallel to the seat width direction in the state of being. 2 is a side view showing a hinge shaft 10, a retractor unit 13, an upper frame 8, a lower frame 7, and the like with respect to the other configuration 2, and the angle formed by the upper frame 8 and the lower frame 7 is the largest within a predetermined range. It shows the state of these various members obtained when the vehicle seat is viewed from a direction parallel to the seat width direction in the state of being. FIG. 2 is a side view showing a hinge shaft 10, a retractor unit 13, an upper frame 8, a lower frame 7, and the like with respect to the other configuration 2, and the angle formed by the upper frame 8 and the lower frame 7 is the smallest within a predetermined range. It shows the state of these various members obtained when the vehicle seat is viewed from a direction parallel to the seat width direction in the state of being.

Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In the following description, the same parts and equivalent parts may be given the same reference numbers, and duplicate explanations may not be repeated.

(Vehicle seat 100)
FIG. 1 is a perspective view showing a vehicle seat 100. The vehicle seat 100 includes a seat cushion 1 and a seat back 2, and a retractor unit 13 and a center folding mechanism 20 described later are provided in the seat back 2. The seat back 2 has a lower seat back 3a and an upper seat back 3b. A headrest 3c is provided on the seat back 2 (upper seat back 3b). The back frame 5 is arranged in the seat back 2.

FIG. 2 is a perspective view showing a configuration on the back side of the back frame 5 provided in the vehicle seat 100. The back frame 5 has a pair of side frame portions 6R and 6L and an upper frame portion 9. The upper frame portion 9 extends in the seat width direction and connects the upper portions of the pair of side frame portions 6R and 6L.

The side frame portions 6R and 6L are separated from each other in the seat width direction, and beam members 11 and 35 are provided in a bridging shape between them. A reclining mechanism 4 is provided at the lower ends of each of the side frame portions 6R and 6L, and the reclining mechanism 4 enables the seat back 2 (FIG. 1) to tilt in the front-rear direction of the seat with respect to the seat cushion 1 (FIG. 1).

Each of the pair of side frame portions 6R and 6L has a lower frame 7 and an upper frame 8 (FIG. 2). The lower frame 7 constitutes the skeleton of the lower seat back 3a (FIG. 1), and the upper frame 8 constitutes the skeleton of the upper seat back 3b (FIG. 1). A bracket 26 is joined to the lower end of the upper frame 8 by welding or the like.

The hinge shaft 10 is inserted through the bracket 26, and the nut 23 is tightened to the threaded portion of the hinge shaft 10. The upper frame 8 and the lower frame 7 are connected to each other in the front-rear direction of the seat so as to be relatively rotatable via the center folding mechanism 20, specifically, the bracket 26 and the hinge shaft 10 extending in the seat width direction. ..

(Retractor unit 13)
FIG. 3 is a perspective view showing a configuration on the back side of the side frame portion 6R and the like. As shown in FIG. 3, the beam material 11 supports the retractor unit 13 via the support bracket 12B. The retractor unit 13 has a cylindrical portion (retractor portion) for winding the seat belt 15, and a belt support portion 13B is arranged above the retractor portion.

The belt support portion 13B has a guide hole 13A extending in a slit shape inside, and the webbing of the seat belt 15 wound around the retractor unit 13 (cylindrical retractor portion) is moved upward through the guide hole 13A. It is paid out. The belt support portion 13B guides and supports the webbing of the seat belt 15 drawn out from the retractor portion toward the shoulder opening of the back frame 5.

A belt guide 14 and a cover 16 (FIG. 1) are arranged on the shoulder opening of the back frame 5. The seat belt 15 pulled upward from the retractor unit 13 extends so as to follow the surface shape of the belt guide 14. The seat belt 15 is arranged so as to get over the upper frame portion 9 from the rear side to the front side by folding back at the top of the belt guide 14. The seat belt 15 is pulled out to the front side from the pull-out port 17 provided on the cover 16. The seat belt 15 is pulled out from the inside of the seat back 2 through the position of the shoulder opening of the seat back 2.

In the vehicle seat 100, the retractor unit 13 for winding the seat belt 15 is connected to the beam material 11 via the support bracket 12B. The load due to the tension acting on the seatbelt 15 when the seatbelt 15 is operated is transmitted to the side frame portions 6R and 6L via the support bracket 12B and the beam material 11. In the vehicle seat 100, the beam material 11 is supported by the lower frame 7, and the load by the seat belt 15 is particularly transmitted to the lower frame 7.

(Middle folding mechanism 20)
As shown in FIG. 3, a center folding mechanism 20 is interposed between the lower frame 7 and the upper frame 8. The motor 41 that functions as a drive source for the center folding mechanism 20 is arranged between the side frame portions 6R and 6L in the seat width direction.

The beam material 11 supports the motor 41 via the support bracket 12A. The driving force from the motor 41 is transmitted to the center bending mechanism 20 via the torque cable 34. The center folding mechanism 20 adjusts the angle between the upper frame 8 and the lower frame 7 in the front-rear direction of the seat (see the angle θ in FIGS. 7 and 8) within a predetermined range.

FIG. 4 is a perspective view showing the configuration of the side frame portion 6R, the center folding mechanism 20, and the like on the front side. FIG. 5 is a perspective view showing the configuration of the side frame portion 6R and the center folding mechanism 20 on the back side. In FIG. 4, for convenience of explanation, a part of the side frame portion 6R and a part of the bracket 26 are broken and shown. A part of the center folding mechanism 20 is arranged inside the side frame portion 6R and inside the bracket 26, and is difficult to see from the outside. However, in FIG. 4, the entire center folding mechanism 20 is for convenience of explanation. It is virtually exposed.

FIG. 6 is a perspective view showing a disassembled state of the center folding mechanism 20. In FIG. 6, the center folding mechanism 20 is shown at a position separated inward in the seat width direction from the lower frame 7 and the upper frame 8. In the present embodiment, the center folding mechanism 20 is actually arranged inside the side frame portion 6R (see FIG. 5). In particular, the fulcrum link 22 and the eccentric ring 27, and the sector gear 42 and the pinion 43 constituting the center bending mechanism 20 are provided between the inner panel portions 7a and 8a and the outer panels 7b and 8b and brackets shown in FIG. It is arranged inside the 26.

As shown in FIGS. 3 to 6, the lower frame 7 (FIG. 5) includes an inner panel portion 7a and an outer panel 7b, and has a bag-shaped (rectangular) cross-sectional structure extending in the front-rear direction as a whole. Similarly, the upper frame 8 also includes an inner panel portion 8a and an outer panel 8b, and has a bag-shaped (rectangular) cross-sectional structure extending in the front-rear direction as a whole.

The center folding mechanism 20 has an eccentric ring 27 as a first link member and a fulcrum link 22 as a second link member. A substantially arm-shaped fulcrum link 22 as a second link member is arranged between the inner panel portion 7a and the outer panel 7b (FIGS. 5 and 6).

A bush 21 is provided at the lower end of the fulcrum link 22. The bush 21 is arranged below the hinge shaft 10 (FIG. 4), and the bolt 24 is inserted into the bush 21. The lower end of the fulcrum link 22 is rotatably supported by both the inner panel 7a and the outer panel 7b via bushes 21, bolts 24 and nuts 25 (FIG. 5).

As shown in FIG. 6, a mounting hole 22b is formed at the upper end of the fulcrum link 22, and a bearing hole 22c is formed at the intermediate portion of the fulcrum link 22. The center line of the mounting hole 22b is located above the lower frame 7, and the center line of the bearing hole 22c is located below the upper frame 8. The center line of the mounting hole 22b and the center line of the bearing hole 22c both extend in the seat width direction.

An eccentric ring 27 as a first link member is rotatably fitted into the mounting hole 22b of the fulcrum link 22 via a bush. The eccentric ring 27 is rotatable around the center line of the mounting hole 22b. A sector gear 42 is arranged on the opposite side of the eccentric ring 27 with respect to the mounting hole 22b. A connector 28 (FIG. 6) is inserted through the sector gear 42 and the eccentric ring 27, and the sector gear 42 and the eccentric ring 27 are firmly fixed to each other by welding or the like. The eccentric ring 27 is prevented from falling out of the mounting hole 22b by this fixing.

A mounting hole 27c is formed in the eccentric ring 27, and an eccentric hole 42b is formed in the sector gear 42. The threaded portion of the bolt 32 is rotatably inserted into the mounting hole 27c and the eccentric hole 42b via a bush or the like. The bolt 32 is inserted into the bracket 26, and the nut 33 is tightened to the threaded portion of the bolt 32. The eccentric ring 27 and the sector gear 42 are rotatably supported by both the inner panel portion 8a and the outer panel 8b via the bracket 26. The position of the bolt 32 is diagonally rearward and upward of the hinge shaft 10.

The eccentric ring 27 and the sector gear 42 are supported here by both the inner panel portion 8a and the outer panel 8b via the bracket 26. The bracket 26 may be used as needed. When the bracket 26 is not used, the bolt 32 may be arranged so as to be inserted into the inner panel portion 8a and the outer panel 8b. The eccentric ring 27 and the sector gear 42 may be directly supported by both the inner panel portion 8a and the outer panel 8b. Spacers 29 (FIGS. 5 and 6) may be arranged between the bracket 26 and the sector gear 42, if necessary.

The center bending mechanism 20 is configured by an eccentric ring 27 and a fulcrum link 22 (excluding the sector gear 42 and the pinion 43) interposed between the lower frame 7 and the upper frame 8. A pinion 43 (FIG. 6) is further pivotally supported by the fulcrum link 22. The pinion 43 is inserted into the bearing hole 22c of the fulcrum link 22 and meshes with the sector gear 42.

A pair of gear cases 44, 45 that rotatably support the pinion 43 are attached to the fulcrum link 22. The gear cases 44 and 45 rotatably accommodate the worm wheels 46a, worms 47a and helical gears 46b, 47b. The pinion 43 is rotatably supported by the gear cases 44 and 45 via the worm wheel 46a, the worm 47a and the helical gears 46b and 47b. The gear cases 44 and 45 are fixed to each other by the ring plate 50. The gear cases 44 and 45 are integrally fastened to the fulcrum link 22 by bolts 51 (FIGS. 4 and 6).

The gear cases 44, 45, the worm wheel 46a, the worm 47a, and the helical gears 46b, 47b constitute the reduction gear 55 (FIG. 6). The torque cable 34 has a core portion 34a and a tube 34b. The driving force from the motor 41 is transmitted to the pinion 43 via the worm 48, the worm wheel 49, the torque cable 34, and the speed reducer 55 described above. When the rotation shaft of the motor 41 rotates, the pinion 43 rotates and the sector gear 42 that meshes with the pinion 43 rotates.

(Operation of center folding mechanism 20)
FIG. 7 is a side view showing the center folding mechanism 20, the upper frame 8 and the lower frame 7, and shows a state in which the angle θ formed by the upper frame 8 and the lower frame 7 is the largest within a predetermined range. .. FIG. 8 is a side view showing the center folding mechanism 20, the upper frame 8 and the lower frame 7, and shows a state in which the angle θ formed by the upper frame 8 and the lower frame 7 is the smallest within a predetermined range. .. FIG. 9 is a perspective view showing a state in which the upper frame 8 is tilted most forward with respect to the lower frame 7, which corresponds to FIG.

The center bending mechanism 20 has an eccentric ring 27 and a fulcrum link 22, and is driven by a sector gear 42 and a pinion 43. The eccentric ring 27 is rotatably connected to the upper frame 8 via the bracket 26. The fulcrum link 22 is rotatably connected to the upper frame 8 via the bracket 26, and is also rotatably connected to the lower frame 7.

The sector gear 42 rotates integrally with the bracket 26 and the upper frame 8 about a connecting point (connecting tool 28) between the upper frame 8 and the lower frame 7. The pinion 43 is pivotally supported by the lower frame 7, is rotationally driven by the motor 41, and meshes with the sector gear 42.

In the state shown in FIG. 7, when the pinion 43 is rotationally driven in the counterclockwise direction by the motor 41 (see FIG. 8), the sector gear 42 and the eccentric ring 27 are integrally driven as a fulcrum centering on the position of the connector 28. It rotates clockwise with respect to the link 22 (see FIG. 8). In this case, the distance L1 between the bolt 32 and the bolt 24 gradually increases, and the angle θ gradually decreases. Along with this, the upper frame 8 is gradually inclined with respect to the lower frame 7. When the upper frame 8 is inclined most forward with respect to the lower frame 7, the appearance as shown in FIG. 9 can be obtained.

In the state shown in FIG. 8, when the pinion 43 is rotationally driven in the clockwise direction by the motor 41, the sector gear 42 and the eccentric ring 27 are integrated with respect to the fulcrum link 22 centered on the position of the connector 28. Rotate clockwise. In this case, the distance L2 between the bolt 32 and the bolt 24 gradually decreases, and the angle θ gradually increases. Along with this, the upper frame 8 gradually stands up against the lower frame 7.

By the above operation, the rotation angle θ formed by the lower frame 7 and the upper frame 8 is adjusted. As shown in FIGS. 7 and 8, both ends in the circumferential direction of the gear portion of the sector gear 42 reach either end (the rearmost or the frontmost of the meshable range with the pinion 43), and the pinion 43 reaches the pinion 43. (And the sector gear 42) are molded so that rotation is restricted. Therefore, the rotation angle formed by the lower frame 7 and the upper frame 8 is limited to a predetermined range corresponding to the range between the rotation positions where the sector gear 42 is restricted from rotating.

(Relative positions of hinge shaft 10, belt support 13B, seat belt 15, etc.)
FIG. 10 is a side view showing the hinge shaft 10, the retractor unit 13, the upper frame 8, the lower frame 7, and the like, and the angle formed by the upper frame 8 and the lower frame 7 is the largest within a predetermined range. It shows the state of these various members obtained when the vehicle seat 100 is viewed from a direction parallel to the seat width direction.

As shown in FIG. 10, when the vehicle seat 100 is viewed from a direction parallel to the seat width direction in a state where the angle θ formed by the upper frame 8 and the lower frame 7 is the largest within a predetermined range. Defines a first vertical plane S1, a second vertical plane S2, and a two-dimensional plane S3.

The first vertical plane S1 is a plane that passes through the hinge shaft 10 and is parallel to the vertical direction. The second vertical plane S2 is a plane that passes through the outlet 17 and is parallel to the vertical direction. The two-dimensional plane S3 is a plane formed by a two-dimensional plane passing through both the hinge shaft 10 and the outlet 17. The belt support portion 13B in the vehicle seat 100 is arranged between the first vertical plane S1 and the second vertical plane S2 and below the two-dimensional plane S3.

(Action and effect)
As mentioned at the beginning, the vehicle seat provided with the center folding mechanism on the seat back tends to have lower rigidity and strength than the case without the center folding mechanism. It is desired that the seatbelt pull-out outlet is provided at the shoulder opening of the seatback and the seatback has a center-folding mechanism so as to have a structure that can more withstand the load generated when the seatbelt is operated.

With reference to FIG. 10, when the seat belt 15 is operated, a tensile force is generated on the seat belt 15. A tensile force F1b acts on one side (front side) of the seat belt 15, and a tensile force F1r acts on the other side (lower side) of the seat belt 15. Due to the generation of the tensile forces F1b and F1r, an apparent synthetic force F1br acts on the vehicle seat 100 (particularly, the back frame 5). A distance L1br is provided between the position where the combined force F1br acts and the hinge shaft 10.

When the seat belt 15 is operated, a moment M1A (= F1br × L1br) acts around the hinge shaft 10. The vehicle seat 100 having a structure capable of reducing the moment M1A can more withstand the load generated when the seat belt is operated. Here, since the direction in which the tensile force F1b acts may vary depending on the physique of the occupant or the like, it is difficult to control the direction in which the tensile force F1b acts.

On the other hand, the smaller the distance L1br, the smaller the moment M1A becomes. The distance L1br fluctuates according to the direction in which the combined force F1br is directed, and the direction in which the combined force F1br is facing fluctuates according to the direction in which the tensile force F1r is facing. The direction in which the tensile force F1r is directed varies depending on the position of the belt support portion 13B.

In the vehicle seat 100, the belt support portion 13B is arranged between the first vertical plane S1 and the second vertical plane S2 and below the two-dimensional plane S3. According to this configuration, the distance L1br can be made sufficiently small, and the moment M1A can be made small. The load acting on the center-folding mechanism 20 can be reduced, and as a result, a vehicle seat 100 having the center-folding mechanism 20 having a structure that can withstand the load generated when the seatbelt is operated can be obtained.

FIG. 11 is a side view showing the hinge shaft 10, the retractor unit 13, the upper frame 8, the lower frame 7, and the like, and the angle formed by the upper frame 8 and the lower frame 7 is the smallest within a predetermined range. It shows the state of these various members obtained when the vehicle seat 100 is viewed from a direction parallel to the seat width direction.

When the seat belt 15 is operated, a tensile force is generated on the seat belt 15. A tensile force F2b acts on one side (front side) of the seat belt 15, and a tensile force F2r acts on the other side (lower side) of the seat belt 15. Due to the generation of the tensile forces F2b and F2r, an apparent synthetic force F2br acts on the vehicle seat 100 (particularly, the back frame 5). A distance L2br is provided between the position where the combined force F2br acts and the hinge shaft 10. When the seat belt 15 is operated, a moment M1B (F2br × L2br) acts around the hinge shaft 10.

As described above, in the vehicle seat 100 (see FIG. 10), the belt support portion 13B is between the first vertical plane S1 and the second vertical plane S2 and below the two-dimensional plane S3. Have been placed. According to this configuration, the moment M1B can be reduced. The load acting on the center-folding mechanism 20 can be reduced, and as a result, a vehicle seat 100 having the center-folding mechanism 20 having a structure that can withstand the load generated when the seatbelt is operated can be obtained.

By reducing the load input to the center bending mechanism 20, it is possible to reduce the size of the center folding mechanism 20. By arranging at least one of the eccentric ring 27, the fulcrum link 22, the sector gear 42, and the pinion 43 inside the side frame portion 6R, it is possible to reduce the size of the vehicle seat 100 as a whole. .. In the present embodiment, all of these four are arranged inside the side frame portion 6R, and it is possible to further reduce the size. The same applies to the side frame portion 6L.

The eccentric ring 27 is rotatably supported by both the inner panel portion 8a and the outer panel 8b via the bracket 26. The fulcrum link 22 is also rotatably supported by both the inner panel 7a and the outer panel 7b. A so-called double-sided structure is configured in the support structure of the eccentric ring 27 and the support structure of the fulcrum link 22, and the eccentric ring 27 and the fulcrum link 22 can operate stably and with a high load capacity. This configuration can also contribute to the miniaturization of the vehicle seat 100.

In the vehicle seat 100 of the present embodiment, it is possible to effectively suppress the increase in size that may occur due to the addition of the center folding mechanism 20 and the retractor unit 13 to the vehicle seat 100.

(Modification example)
With reference to FIG. 10 again, the belt support portion 13B may be arranged at the following positions.

(Modification example 1)
When the vehicle seat 100 is viewed from a direction parallel to the seat width direction, a plane that passes through the hinge shaft 10 and is parallel to the horizontal direction is defined as a reference plane LN, and passes through the hinge shaft 10 and is a reference plane. A plane inclined upward by an angle θ1 (= 60 °) with respect to the LN is defined as an upper side surface LN1, and is a plane inclined by an angle θ2 (= 30 °) downward with respect to the reference plane LN and passing through the hinge axis 10. Is defined as the lower side surface LN2. In this case, the belt support portion 13B may be arranged at a position below the upper side surface LN1 and above the lower side surface LN2.

(Modification 2)
When the vehicle seat 100 is viewed from a direction parallel to the seat width direction, the belt support portion 13B may be arranged at a position above the reference surface LN. Even with such a configuration, the same action and effect can be obtained.

(Modification 3)
When the vehicle seat 100 is viewed from a direction parallel to the seat width direction, the belt support portion 13B may be arranged at a position that does not overlap the side frame portions 6R and 6L. In other words, when the belt support portion 13B is virtually projected in the seat width direction, the vehicle seat 100 may be configured so that the projected image does not overlap the side frame portions 6R and 6L.

(Other configuration 1)
In the above embodiment, the retractor unit 13 is connected to the lower frame 7. The load due to the tension acting on the seat belt 15 when the seat belt 15 is operated is transmitted to the side frame portions 6R and 6L via the support bracket 12B and the beam material 11. The beam material 11 is supported by the lower frame 7, and the load by the seat belt 15 is particularly transmitted to the lower frame 7.

In the examples shown in FIGS. 12 and 13, the retractor unit 13 and the belt support portion 13B are supported by the upper frame 8. 12 and 13 correspond to FIGS. 10 and 11, respectively, in the above-described embodiment. In the configurations shown in FIGS. 12 and 13, for example, the beam material 11 is supported by the upper frame 8. The load from the seat belt 15 is particularly transmitted to the upper frame 8.

Even when this configuration is adopted, the belt support portion 13B is between the first vertical plane S1 (see FIG. 10; the same applies hereinafter) and the second vertical plane S2, and is a two-dimensional plane S3. By arranging the seats lower than the above, a vehicle seat having a center-folding mechanism 20 having a structure capable of more withstanding the load generated when the seatbelt is operated can be obtained.

It is presumed that the moment M2A (FIG. 12) and the moment M2B (FIG. 13) generated by the configuration are larger than the moment M1A (FIG. 10) and the moment M1B (FIG. 11) in the above-described embodiment. That is, it is presumed that the relationship of M2A> M1A and the relationship of M2B> M1B are established.

(Other configuration 2)
In the examples shown in FIGS. 14 and 15, the retractor unit 13 and the belt support portion 13B are arranged in the vicinity of the bolt 24 of the lower frame 7. As described above, the bolt 24 is a portion that rotatably supports the lower end portion of the fulcrum link 22 via the bush 21. 14 and 15 correspond to FIGS. 10 and 11, respectively, in the above-described embodiment.

Even when this configuration is adopted, the belt support portion 13B is between the first vertical plane S1 (see FIG. 10; the same applies hereinafter) and the second vertical plane S2, and is a two-dimensional plane S3. By arranging the seats lower than the above, a vehicle seat having a center-folding mechanism 20 having a structure capable of more withstanding the load generated when the seatbelt is operated can be obtained.

The moment M3A (FIG. 14) and the moment M3B (FIG. 15) generated by the configuration are larger than the moment M1A (FIG. 10) and the moment M1B (FIG. 11) in the above-described embodiment, and the moment M2A (FIG. 11) It is presumed that it is smaller than that of FIG. 12) and the moment M2B (FIG. 13). That is, it is presumed that the relationship of M2A> M3A> M1A and the relationship of M2B> M3B> M1B are established.

Although the embodiments have been described above, the above-mentioned disclosure contents are examples in all respects and are not restrictive. The technical scope of the present invention is indicated by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 seat cushion, 2 seat back, 3a lower seat back, 3b upper seat back, 3c headrest, 4 reclining mechanism, 5 back frame, 6L, 6R side frame part, 7 lower frame, 7a, 8a inner panel part, 7b, 8b Outer panel, 8 upper frame, 9 upper frame, 10 hinge shaft, 11,35 beam material, 12A, 12B support bracket, 13 retractor unit, 13A guide hole, 13B belt support, 14 belt guide, 15 seat belt, 16 Cover, 17 outlet, 20 center bending mechanism, 21 bush, 22 link, 22b, 27c mounting hole, 22c bearing hole, 23,25,33 nut, 24,32,51 bolt, 26 bracket, 27 eccentric ring, 28 connection Tools, 29 spacers, 34 torque cables, 34a cores, 34b tubes, 41 motors, 42 sector gears, 42b eccentric holes, 43 pinions, 44,45 gear cases, 46a, 49 worm wheels, 46b, 47b helical gears, 47a, 48 worms, 50 ring plate, 55 speed reducer, 100 vehicle seat, F1r, F1b, F2b, F2r tensile force, F1br, F2br combined force, L1br, L1, L2, L2br distance, LN reference plane, LN1 upper side, LN2 lower side, M1B, M1A, M2A, M2B, M3A, M3B moment, S1 first vertical face, S2 second vertical face, S3 two-dimensional plane.

Claims (6)

It ’s a vehicle seat,
With the seat back
A back frame, which is arranged in the seat back and has a pair of side frame portions and an upper frame portion that connects the upper portions of the pair of side frame portions.
A retractor unit having a belt support and arranged inside the vehicle seat,
The retractor unit is pulled out upward from the belt support portion, and is arranged so as to get over the upper frame portion from the rear side to the front side, and is arranged from the inside of the seat back through an outlet provided at the shoulder opening of the seat back. With a seat belt pulled out to the outside,
Each of the pair of side frame portions has an upper frame and a lower frame, and the upper frame and the lower frame are connected to each other via a hinge shaft so as to be relatively rotatable in the front-rear direction of the seat.
The retractor unit is connected to the lower frame and is connected to the lower frame.
The vehicle seat further includes a center folding mechanism capable of adjusting the angle between the upper frame and the lower frame in the front-rear direction of the seat within a predetermined range.
When the vehicle seat is viewed from a direction parallel to the seat width direction in a state where the angle formed by the upper frame and the lower frame is the largest within the predetermined range, the vehicle passes through the hinge axis. Assuming that the first vertical surface, the second vertical surface passing through the outlet, and the two-dimensional plane passing through both the hinge shaft and the outlet are defined, the belt support portion is defined as the first vertical surface. It is located between the second vertical plane and below the two-dimensional plane.
Vehicle seat. When the vehicle seat is viewed from a direction parallel to the seat width direction,
A plane that passes through the hinge axis and is parallel to the horizontal direction is defined as a reference plane.
A plane that passes through the hinge axis and is inclined 60 ° upward with respect to the reference plane is defined as an upper side surface.
Assuming that a plane that passes through the hinge axis and is inclined 30 ° downward with respect to the reference plane is defined as a lower side surface.
The belt support portion is arranged at a position below the upper side surface and above the lower side surface.
The vehicle seat according to claim 1. The belt support portion is arranged at a position above the reference plane.
The vehicle seat according to claim 2. When the vehicle seat is viewed from a direction parallel to the seat width direction, the belt support portion is arranged at a position that does not overlap the side frame portion.
The vehicle seat according to claim 1 or 2. The center folding mechanism has a first link member rotatably connected to the upper frame and a second link member rotatably connected to both the upper frame and the lower frame.
The center folding mechanism includes a sector gear that rotates integrally with the upper frame around a connection point between the upper frame and the lower frame, and is pivotally supported by the lower frame and rotationally driven, and meshes with the sector gear. Driven by a pinion and
At least one of the first link member, the second link member, the sector gear, and the pinion is arranged inside the side frame portion.
The vehicle seat according to any one of claims 1 to 4. The side frame portion has an inner panel portion and an outer panel portion.
At least one of the first link member and the second link member is rotatably supported by both the inner panel portion and the outer panel portion.
The vehicle seat according to claim 5.

Images