JP2023120968A - Vehicular seat back - Google Patents

Abstract

To support a back of an occupant and reduce discomfort caused to the occupant.SOLUTION: A vehicular seat back 11 includes: a seat back frame 2; a pressure receiving member 4 which is located within the seat back frame and receives a load from a back of an occupant 9; and connection members 81, 82 which connect the pressure receiving member to the seat back frame. The pressure receiving member has: a body 6; and a rigid member 7 which is fixed to the rear side of the body in a position corresponding to a chest 91 of the occupant. The rigid member extends in a width direction of the seat back and is connected at multiple portions whose positions are different in the width direction to the seat back frame by the connection members.SELECTED DRAWING: Figure 5

Description

The technology disclosed herein relates to a vehicle seat back.

Patent Literature 1 describes a seat back for a vehicle. The seatback includes a seatback frame, a cushion pad, and a pressure receiving member. The pressure receiving member is a resin plate. The pressure receiving member is positioned behind the cushion pad and attached to the seat back frame via a wire. The wire is molded integrally with the pressure receiving member by insert molding. The pressure receiving member receives a load from the back of the occupant. Further, when an impact load from the occupant's back is input to the pressure-receiving member in the event of a rear-end collision of the vehicle, the pressure-receiving member is pushed by the occupant's back and moves rearward together with the occupant. The displacement of the pressure-receiving member reduces the impact load acting on the occupant's neck during a collision.

JP 2019-182273 A

In the conventional vehicle seat disclosed in Patent Document 1, a pressure receiving member made of resin and a wire are integrally formed by insert molding. The rigidity of the pressure receiving member must be high in order to reliably receive the load from the back of the occupant. On the other hand, if the rigidity of the pressure receiving member is too high, the reaction force against the back of the occupant will be too strong, giving the occupant a sense of discomfort. Unfortunately, conventional vehicle seats do not eliminate this problem.

The technology disclosed herein achieves both support for the back of the occupant and reduction of discomfort felt by the occupant.

The technology disclosed herein relates to a vehicle seat back. Vehicle seat backs are
a seat back frame;
a pressure receiving member positioned within the seat back frame and receiving a load from the back of the occupant;
a connecting member that connects the pressure receiving member to the seat back frame;
The pressure receiving member has a main body and a rigid member fixed to the rear side of the main body at a position corresponding to the occupant's ribcage,
The rigid member extends in the width direction of the seatback, and is connected to the seatback frame by the connection member at a plurality of positions at different positions in the width direction.

According to this configuration, the pressure receiving member is attached to the seatback frame via the connecting member. The pressure receiving member receives a load from the back of the occupant and supports the back of the occupant.

The pressure receiving member has a main body and a rigid member. The rigid member is fixed to the rear side of the main body at a position corresponding to the occupant's ribcage. The rigid member also extends in the width direction of the seatback, and is connected to the seatback frame by connecting members at a plurality of positions at different positions in the width direction. Since the main body is connected to the seat back frame via the rigid member, the pressure receiving member can firmly support the back of the occupant. For example, in the event of a vehicle rear-end collision, the pressure-receiving member can support the back of an occupant who receives an impact load.

On the other hand, during normal running of the vehicle, the load from the occupant's back is received by the main body of the pressure receiving member, which has relatively low rigidity. The reaction force against the back of the occupant is suppressed from becoming too strong, and the discomfort felt by the occupant is reduced.

Therefore, the vehicle seat back described above can support the back of the occupant and reduce discomfort felt by the occupant.

The main body has a base located in the center in the width direction of the seat back, and a plurality of side pieces extending outward in the width direction from both sides of the base,
a connection point between the rigid member and the connecting member is on the central side corresponding to the position of the base;
The rigid member may be fixed to the base on the central side of the connecting portion.

The central portion, or base, of the body is relatively stiff, and the side portions, or side pieces, of the body are relatively less stiff. Further, the connection point between the rigid member and the connecting member is the central portion of the main body corresponding to the position of the base, and the rigid member is fixed to the base on the central side of the connection point. As a result, the pressure receiving member can firmly support the center of the back of the occupant during normal running of the vehicle.

The rigid member may extend outward beyond the tip of the side piece.

The rigid member elongated in the width direction can disperse the load from the occupant input through the main body. The pressure receiving member can firmly support the back of the occupant.

The rigid member may be more rigid outside the position of the connecting member than inside.

By doing so, the rigid member extending in the width direction has relatively low rigidity in the central portion and relatively high rigidity in both side portions. Further, as described above, the rigid member is fixed to the base of the main body at the central portion, and the connection point between the rigid member and the connecting member is located on the central side of the rigid member. Therefore, the load from the back of the occupant is input to the central portion of the relatively low-rigidity rigid member. At this time, the rigidity of the rigid member differs in the longitudinal direction, so that the central portion and the side portions are displaced in opposite directions, that is, when the central portion is displaced rearward, the side portions are displaced forward and the central portion is displaced forward. When the part is displaced forward, the sides can absorb the load by displacing back. The pressure receiving member can firmly support the back of the occupant.

The base may be positioned above the position of the side piece and have a fixing portion fixed to the rigid member.

By doing so, the rigid member fixed to the fixing portion at the upper end portion of the main body can firmly support the pressure receiving member.

Further, by positioning the rigid member located on the rear side of the main body at the upper end portion of the main body, a wide space can be secured on the rear side of the main body and below the rigid member. When a lumbar support that moves up and down is positioned on the rear side of the main body, the movable range of the lumbar support increases.

As described above, the vehicle seat back can support the back of the occupant and reduce discomfort felt by the occupant.

FIG. 1 shows a vehicle seat. FIG. 2 shows the inside of the seatback as seen from the front. FIG. 3 shows the inside of the seat back viewed from the side. FIG. 4 shows the inside of the seatback as seen from behind. FIG. 5 shows the pressure receiving member as seen from the front. The left diagram of FIG. 6 shows the pressure receiving member seen from the side, and the right diagram shows the pressure receiving member seen from behind. FIG. 7 shows the VII-VII end face of FIG. FIG. 8 shows the rear surface of the pad. FIG. 9 shows a modification of the rear surface of the pad.

Hereinafter, embodiments of a vehicle seat back will be described with reference to the drawings. The seat back described here is an example.

(Overall structure of seat back)
A vehicle seat 1 is installed in a vehicle interior as a front seat. In the following description, the front, rear, left, right, and top and bottom of the vehicle seat 1 correspond to the front, rear, left, and right, and the top and bottom of the vehicle when the vehicle seat 1 is installed in the vehicle interior. The left-right direction corresponds to the width direction of the vehicle seat.

As shown in FIG. 1 , the vehicle seat 1 includes a seat back 11 , a seat cushion 12 and a headrest 13 . The seat back 11 supports the back of the occupant 9 (see also FIG. 3). The seat cushion 12 supports the buttocks of the occupant 9. The headrest 13 supports the head of the occupant 9.

The seat back 11 has a frame 2, a pad 3, an outer skin 30, and a pressure receiving member 4, as shown in FIGS.

The frame 2 has left and right side frames 21 , an upper frame 22 and a lower frame 23 . The upper frame 22 connects the upper end portions of the left and right side frames 21 in the left-right direction. The lower frame 23 connects the lower ends of the left and right side frames 21 in the left-right direction. The frame 2 is a substantially rectangular frame when viewed from the front.

Pad 3 is positioned on the front side of frame 2 . The pad 3 is composed of a foam member 31 and a reinforcing member 32 attached to the rear surface of the foam member 31, as shown in the left diagram of FIG. The foam member 31 is a cushion member made of urethane foam, for example. The reinforcing member 32 is made of nonwoven fabric, for example. The reinforcing member 32 reinforces the rear surface of the foam member 31 . The foam member 31 reinforced by the reinforcing member 32 is elastically deformed by receiving a load from the back of the occupant 9 and imparts an appropriate reaction force to the back of the occupant 9 .

The skin 30 has a substantially bag shape and covers the entire seat back 11 . As will be described later, the vehicle seat 1 has a seat ventilation 5 . The skin 30 is made of a breathable material such as fabric, natural leather or synthetic leather having a large number of pores.

The pressure receiving member 4 is positioned inside the frame 2 behind the pad 3 . The pressure receiving member 4 receives a load from the back of the occupant 9 via the pad 3 . Details of the pressure receiving member 4 will be described later.

An airbag 51 of the seat ventilation 5 is positioned between the pad 3 and the pressure receiving member 4, as shown in the left diagram of FIG. The airbag 51 prevents the rear surface of the pad 3 from directly contacting the pressure receiving member 4 . The airbag 51 suppresses wear and/or damage to the pad 3 .

The seat ventilation 5 sucks the air in the vehicle interior that has been conditioned by the air conditioner from the surface of the seat back 11 into the seat back 11 . The seat ventilation 5 has an airbag 51 and a fan 52 .

As shown in the left diagram of FIG. 6 or FIG. 8, the foam member 31 has a plurality of through holes 311 . Each through hole 311 penetrates from the front surface to the rear surface of the foam member 31 . The skin 30 is made of a breathable material, as described above.

The fan 52 is located inside the frame 2 and above the pressure receiving member 4, as shown in FIGS. The fan 52 has a suction port 521 on its front surface. The fan 52 has outlets 522 on its left and right sides. The two outlets 522 are open inside the seat back 11 .

The suction port 521 is connected to the rear surface of the airbag 51 . Although not shown in detail, the front surface of the airbag 51 is formed with openings connected to the through holes 311 of the foam member 31 .

When the fan 52 operates, air in the vehicle interior is sucked into the airbag 51 through the skin 30 and the through holes 311 . The airbag 51 functions as a manifold that collects the air sucked through each through hole 311 . The fan 52 sucks the air in the airbag 51 through the suction port 521 and blows it out through the discharge port 522 .

(Structure of pressure receiving member)
The pressure receiving member 4 has a main body 6 and a rigid member 7 .

The body 6 has a base 69 and a plurality of side pieces 60 . The main body 6 has a plate shape with a small thickness in the front-rear direction, and is made of synthetic resin, for example.

The base portion 69 is positioned in the center portion of the seat back 11 in the width direction. The base portion 69 has a substantially rectangular shape when viewed from the front and extends vertically and horizontally. A plurality of holes are formed in the base portion 69 for weight reduction.

The upper end of the base portion 69 is located at a position corresponding to the lower portion of the ribcage 91 of the occupant 9 (see also FIG. 5). A lower end of the base portion 69 is located at a position corresponding to the waist of the occupant 9 . The base portion 69 supports the central portion of the back of the occupant 9 in the left-right direction between a position corresponding to the lower portion of the thorax 91 of the occupant 9 and a position corresponding to the waist. The ribcage 91 includes the clavicle, sternum, ribs and thoracic vertebrae of the human body.

The side pieces 60 extend outward and forward in the width direction from both left and right side edges of the base portion 69 . More specifically, the side pieces 60 extend outward in the width direction from the side edges of the base portion 69 when viewed from the front (see FIG. 5 or FIG. 6, right view), and when viewed from the side. Moreover, it extends forward from the base portion 69 (see the left diagram in FIG. 6). Side piece 60 is angled forward with respect to base 69 .

The plurality of side pieces 60 are arranged at intervals in the vertical direction. The main body 6 includes, in order from the top, a first side piece 61, a second side piece 62, a third side piece 63, a fourth side piece 64, a fifth side piece 65, a sixth side piece 66, and a seventh side piece. 67. Each side piece of the first side piece 61 to the seventh side piece 67 has the same shape on the left and right.

The first side piece 61 is positioned at the upper end of the base 69 . The first side piece 61 has the shortest length in the left-right direction. The first side piece 61 has higher rigidity than the adjacent second side piece 62 . The first side piece 61 is formed with a first hole 611 for weight reduction and/or rigidity adjustment.

The second side piece 62 is positioned below the first side piece 61 . The lengths of the second side piece 62 to the seventh side piece 67 are substantially the same. Two second holes 621 for weight reduction and/or rigidity adjustment are formed in the second side piece 62 .

The third side piece 63 is positioned below the second side piece 62 . A third hole 631 is formed in the third side piece 63 for weight reduction and/or rigidity adjustment.

The fourth side piece 64 is positioned below the third side piece 63 . The fourth side piece 64 is formed with a first recess 641 for improving rigidity. The first recess 614 is recessed from the front to the rear of the fourth side piece 64 (see the left diagram in FIG. 6). A convex portion is formed on the rear surface of the fourth side piece 64 .

The fifth side piece 65 is positioned below the fourth side piece 64 . Similarly to the fourth side piece 64, the fifth side piece 65 is also formed with a second concave portion 651 for improving rigidity.

The sixth side piece 66 is positioned below the fifth side piece 65 . Similarly to the fourth side piece 64, the sixth side piece 66 is also formed with a third concave portion 661 for improving rigidity. The seventh side piece 67 is positioned below the sixth side piece 66 . Similarly to the fourth side piece 64, the seventh side piece 67 is also formed with a fourth concave portion 671 for improving rigidity. The tip of the sixth side piece 66 and the tip of the seventh side piece 67 are connected to each other in the vertical direction.

The rigid member 7 is positioned on the rear side of the main body 6 . A rigid member 7 is fixed to the rear surface of the body 6 . More specifically, a fixed portion 68 that bulges upward from a base portion 69 is formed at the upper end portion of the main body 6 . The fixing portion 68 is positioned above the first side piece 61 . The main body 6 has two fixing parts 68 . The two fixing portions 68 are positioned at the center side of the main body 6 in the left-right direction with a space therebetween in the left-right direction. The rigid member 7 is fixed to each of the rear surfaces of the two fixed portions 68 .

The rigid member 7 is made of synthetic resin, for example. The rigid member 7 is thicker than the plate-shaped main body 6 in the front-rear direction (see also FIG. 7). Metal rods 71 are embedded in both side portions of the rigid member 7, respectively. The metal rods 71 extend horizontally outward from the central portion of the rigid member 7 on both the left and right sides. The rigid member 7 has higher rigidity than the main body 6 with respect to load input in the front-rear direction. A metal rod is not embedded in the central portion of the rigid member 7 . The central portion of the rigid member 7 has relatively low rigidity, and both side portions have relatively high rigidity.

The rigid member 7 extends in the left-right direction near the upper end of the main body 6 . The rigid member 7 overlaps the fixed portion 68 and the first side piece 61 of the main body 6 when viewed from the front. The rigid member 7 is fixed to the main body 6 at its central portion, which has relatively low rigidity. The rigid member 7 extends outward from the tip of the first side piece 61 to the left and right.

The frame 2 supports the pressure receiving member 4 . The connecting member 8 connects the frame 2 and the pressure receiving member 4 .

The connecting member 8 includes an upper connecting member 81 and a lower connecting member 82 . The upper connecting member 81 connects the rigid member 7 and the frame 2 . The lower connecting member 82 connects the lower end of the main body 6 and the frame 2 .

The upper connecting member 81 includes a first upper connecting member 811 on the right side and a second upper connecting member 812 on the left side. The first upper connecting member 811 and the second upper connecting member 812 have symmetrical shapes with respect to the center line of the seat back 11 . Below, the structure of the first upper connecting member 811 will be described in detail, and the description of the structure of the second upper connecting member 812 will be omitted as appropriate.

The first upper connecting member 811 connects the rigid member 7 and the right portion of the upper frame 22 . The connection position between the first upper connecting member 811 and the rigid member 7 is the right portion of the central portion of the rigid member 7 . More specifically, the connecting position between the first upper connecting member 811 and the rigid member 7 is laterally outside the fixed position between the rigid member 7 and the main body 6 (see the right figure in FIG. 5 or FIG. 6). . As shown in FIG. 7, the first upper connecting member 811 is positioned so as to overlap the metal rod 71 embedded in the rigid member 7 in the left-right direction.

The first upper connecting member 811 extends upward from the connection position with the rigid member 7 and then bends obliquely upward to the right at the first bent portion 813 . The first upper connecting member 811 then bends upward at the second bent portion 814 and then reaches the right portion of the upper frame 22 . Similarly, the second upper connecting member 812 also extends straight up from the connection position with the rigid member 7 , then bends obliquely upward to the left at the first bent portion 815 and straight up at the second bent portion 816 . , and then reaches the left portion of the upper frame 22 .

The first upper connecting member 811 and the second upper connecting member 812 are small-diameter rod-like members made of metal. The rigid member 7 and the first upper connecting member 811 and the second upper connecting member 812 are integrally formed by insert molding, for example.

The lower connecting member 82 includes a first lower connecting member 821 on the right side and a second lower connecting member 822 on the left side. The first lower connecting member 821 and the left second lower connecting member 822 have symmetrical shapes with respect to the center line of the seat back 11 . In the following, the structure of the first lower connecting member 821 will be described in detail, and the description of the structure of the second lower connecting member 822 will be omitted as appropriate.

The first lower connecting member 821 connects the lower end portion of the base portion 69 and the right portion of the lower frame 23 . The connection position between the first lower connecting member 821 and the base portion 69 is the right side portion of the base portion 69 .

The first lower connecting member 821 protrudes rightward from the right side of the base 69 and then curves into a U shape. The first lower connecting member 821 is attached to a first attachment portion 231 provided on the right side of the lower frame 23, as shown in FIG. Similarly, the second lower connecting member 822 protrudes leftward from the left side of the base portion 69 , is curved in a U shape, and is attached to the second attachment portion 232 provided on the left side of the lower frame 23 . It is

The first lower connecting member 821 and the second lower connecting member 822 are also small-diameter rod-like members made of metal. The base 69, the first lower connecting member 821 and the second lower connecting member 822 are integrally formed by, for example, insert molding.

The pressure receiving member 4 is fixed to the frame 2 by a pair of upper connecting members 81 and a pair of lower connecting members 82 . The pressure receiving member 4 can be displaced rearward due to elastic deformation of the pair of upper connecting members 81 and the pair of lower connecting members 82 when receiving an impact load from the back of the occupant 9 during a rear-end collision of the vehicle, for example. can. The displacement of the pressure receiving member 4 reduces the impact load acting on the neck of the occupant 9 at the time of collision.

Note that the upper connecting member 81 includes a first upper connecting member 811 and a second upper connecting member 812 instead of including a pair of connecting members of the first upper connecting member 811 and the second upper connecting member 812 as described above. A single member may be formed by connecting the lower ends of the two to each other. Similarly, the lower connecting member 82 includes a first lower connecting member 821 and a second lower connecting member 822, instead of including a pair of connecting members consisting of a first lower connecting member 821 and a second lower connecting member 822. By connecting the connecting members 822 together, they may be one piece.

An intermediate connecting member 83 is positioned on the rear side of the base portion 69 as shown in the right view of FIG. 4 or FIG. The intermediate connecting member 83 connects the rigid member 7 and the lower end portion of the base portion 69 . The intermediate connecting member 83 includes a first intermediate connecting member 831 on the right side and a second intermediate connecting member 832 on the left side. The first intermediate connecting member 831 and the second intermediate connecting member 832 have symmetrical shapes with respect to the center line of the seat back 11 . In the following, the structure of the first intermediate connecting member 831 will be described in detail, and the description of the structure of the second intermediate connecting member 832 will be omitted as appropriate.

The upper end of the first intermediate connecting member 831 is fixed to the rigid member 7 . The fixing position of the first intermediate connecting member 831 in the horizontal direction is the same as the fixing position of the first upper connecting member 811 . The first intermediate connecting member 831 extends downward from the rigid member 7 and then bends obliquely downward to the right. Then, the first intermediate connecting member 831 is bent downward again and reaches the third mounting portion 691 provided at the lower end of the base portion 69 . The lateral positions of the third mounting portion 691 and the first mounting portion 231 are substantially the same. Further, the second intermediate connecting member 832 extends downward from the rigid member 7 , bends diagonally downward to the left, bends downward again, and attaches to the fourth attachment portion 692 provided at the lower end of the base portion 69 . reach. The positions in the left-right direction of the fourth attachment portion 692 and the second attachment portion 232 are substantially the same.

The intermediate connecting member 83 increases the rigidity of the pressure receiving member 4 including the base portion 69 and the rigid member 7 and supports the lumbar support 40 .

The lumbar support 40 is positioned behind the pressure receiving member 4 and supports the waist of the occupant 9 via the pressure receiving member 4 . The lumbar support 40 is substantially V-shaped when viewed from behind. The right side and left side of the lumbar support 40 are engaged with the first intermediate connecting member 831 and the second intermediate connecting member 832, respectively. The lumbar support 40 can change its position in the vertical direction along the first intermediate connecting member 831 and the second intermediate connecting member 832 . The lumbar support 40 can appropriately support the lower back of the occupant 9 by changing its position according to the physique of the occupant 9 . The lumbar support 40 moves up and down between the upper limit UL and the lower limit LL, as shown in FIG. The upper limit UL is a position where the lumbar support 40 and the rigid member 7 interfere. The lower limit LL is the position where the first intermediate connecting member 831 and the second intermediate connecting member 832 bend. The fixed portion 68 that bulges upward positions the upper limit UL at a higher position. The fixing portion 68 expands the lifting range of the lumbar support 40 .

A gearbox 41 containing an electric motor is located below the lumbar support 40 . The electric motor is a driving source for raising and lowering the lumbar support 40 . The gearbox 41 has a worm gear 42 . The worm gear 42 extends straight up from the gearbox 41 . The upper end of the worm gear 42 is fixed to the center portion of the lower end of the lumbar support 40 . Rotation of the electric motor raises and lowers the lumbar support 40 together with the worm gear 42 . A passenger can raise and lower the lumbar support 40 by operating a switch.

(Seat back structure that supports both the back of the occupant and reduces discomfort to the occupant)
As described above, the pressure receiving member 4 is attached to the frame 2 via the connecting member 8 . The pressure receiving member 4 receives the load from the back of the occupant 9 and supports the back of the occupant 9.

The pressure receiving member 4 has a main body 6 and a rigid member 7 . The rigid member 7 is fixed to the rear side of the main body 6 at a position corresponding to the ribcage 91 of the occupant 9 . The rigid member 7 also extends in the width direction of the seat back 11 and is connected to the frame 2 by connecting members 8 at a plurality of positions at different positions in the width direction. Since the main body 6 is connected to the frame 2 via the rigid member 7, the pressure receiving member 4 can firmly support the back of the occupant 9. For example, at the time of a rear-end collision of the vehicle, the pressure receiving member 4 can support the back of the occupant 9 who receives the impact load. As described above, the pressure receiving member 4 can move rearward due to the elastic deformation of the connecting member 8 in the event of a rear-end collision.

On the other hand, during normal running of the vehicle, the load from the back of the occupant 9 is received by the main body 6 of the pressure receiving member 4 having relatively low rigidity. The reaction force against the back of the occupant 9 is suppressed from becoming too strong, and the uncomfortable feeling of the occupant 9 is reduced.

Therefore, the vehicle seat back 11 can both reliably support the back of the occupant 9 and reduce the uncomfortable feeling of the occupant 9 .

Further, in the main body 6 having the base portion 69 and the side pieces 60, the central portion of the main body 6, ie the base portion 69, is relatively rigid, and the side portions, ie, the side pieces 60 are relatively rigid. The connection point between the rigid member 7 and the connecting member 8 is on the central side corresponding to the position of the base portion 69, and the rigid member 7 is connected to the base portion 69 on the central side of the connection point between the rigid member 7 and the connecting member 8. Fixed. As a result, the pressure receiving member 4 can firmly support the central side of the back of the occupant 9 during normal running of the vehicle.

Further, since the rigid member 7 extends in the width direction, the load from the occupant 9 input through the main body 6 can be dispersed. This also allows the pressure receiving member 4 to firmly support the back of the occupant 9 .

Both side portions of the rigid member 7 have relatively high rigidity due to the embedding of the metal rods 71, and the central portion has relatively low rigidity. A load from the back of the occupant 9 is input to the central portion of the rigid member 7 having relatively low rigidity. Due to the difference in rigidity of the rigid member 7 in the longitudinal direction, the central portion and both side portions of the rigid member 7 are displaced in opposite directions when a load is applied. That is, when the central portion is displaced rearward, both side portions are displaced forward, and when the central portion is displaced forward, both side portions are displaced rearward, whereby the rigid member 7 can receive the load. The pressure receiving member 4 can firmly support the back of the occupant 9 .

Further, since the fixing portion 68 of the base portion 69 is positioned above the position of the side piece 60 , the rigid member 7 fixed to the upper end portion of the main body 6 can firmly support the pressure receiving member 4 .

(Seat back structure that suppresses changes in the occupant's posture during turns without deteriorating ride comfort)
As shown in FIG. 8, the pad 3 has reinforcement depressions 321 . The reinforcement lowering portion 321 lowers the reinforcement of the reinforcing member 32 attached to the rear surface of the foam member 31 . A lower reinforcement portion 321 in FIG. 8 is a notch formed in the reinforcement member 32 .

As shown in FIG. 2 , the lowered reinforcement portion 321 is positioned so as to overlap the left and right first side pieces 61 when viewed from the direction orthogonal to the surface of the seat back 11 . This position corresponds to the lower portion of the ribcage 91 of the occupant 9, as shown in FIG. The two reinforcing lowered portions 321 are positioned symmetrically with respect to the center line of the seat back 11 .

The reinforcement lowered portion 321 has a substantially 1/4 circular shape when viewed from the rear in the illustrated example. It should be noted that the shape of the reinforcement lowering portion 321 is not limited to the illustrated example. The reduced reinforcement portion 321 may have a polygonal shape, a circular shape, or an elliptical shape when viewed from the rear.

As described above, the base portion 69 of the main body 6 of the pressure receiving member 4 is positioned in the widthwise central portion of the seat back 11 and supports the central portion of the back of the occupant 9 . The side pieces 61 to 67 are positioned on both sides of the base 69 to support the back of the occupant 9 on both sides.

When the vehicle travels straight, the pressure receiving member 4 receives the load from the entire back of the occupant 9 via the pad 3 . The pad 3 has the foam member 31 and the reinforcing member 32 as described above. The load from the back of the occupant 9 is received mainly by the base portion 69 of the pressure receiving member 4 while the foam member 31 reinforced by the reinforcing member 32 undergoes compression deformation. The pad 3 and the pressure receiving member 4 receive the load from the back of the occupant 9 over the entire wide surface. Therefore, when the vehicle travels straight, the seat back 11 can firmly support the back of the occupant 9 without exerting a strong reaction force on the back of the occupant and deteriorating the ride comfort.

When the vehicle turns, the posture of the occupant 9, ie, the driver or passenger, tends to change in the direction in which the ribcage 91 rotates around the spinal column and/or in the direction in which the ribcage 91 tilts left and right. As the posture of the occupant 9 changes, a load is locally input to the seat back 11 from the side of the back of the occupant 9 .

Localized loads from the sides of the back of the occupant 9 are input to the pad 3 at the locations of the reinforcement depressions 321 corresponding to the ribcage 91 . At the initial stage of local load input, the foam member 3 is greatly compressed and deformed at the portion where the reinforcement is lowered 321 . This suppresses a strong reaction force from acting on the occupant 9 at the initial stage of inputting the local load.

After the foam member 31 is compressed and deformed, the local load from the side of the back of the occupant 9 is received mainly by the first side piece 61 of the pressure receiving member 4 . Then, a reaction force acts on the side of the back of the occupant 9 from the pressure receiving member 4 through the pad 3 . Thereby, a change in the posture of the occupant 9 is suppressed.

Therefore, the seat back 11 can suppress a strong reaction force on the occupant 9 and firmly support the back of the occupant 9 to suppress a change in posture when the vehicle turns.

On the other hand, the reduced reinforcement portion 321 is partially provided at a specific portion of the pad 3 . When a load is input to the seat back 11 from the entire back of the occupant 9, such as when the vehicle is traveling straight ahead, the reduced reinforcement portion 321 does not substantially function. The seat back 11 does not degrade the riding comfort when the vehicle travels straight.

Therefore, the seat back 11 can suppress a change in the posture of the occupant 9 during turning without deteriorating ride comfort during straight traveling and turning.

In addition, the reduced reinforcement portions 321 are positioned on both sides of the center line of the seat back 11 in the width direction. That is, the lower reinforcement portions 321 are positioned on the right and left sides of the back of the occupant 9, respectively. The seat back 11 can suppress a change in the posture of the occupant 9 when turning to the right and turning to the left.

Further, the first side piece 61 that overlaps the lower reinforcement portion 321 has higher rigidity than the second side piece 62 . The highly rigid first side piece 61 can apply a sufficient reaction force to the side of the back of the occupant 9 . As a result, it is possible to suppress changes in the posture of the occupant 9 when the vehicle turns.

In addition, since the reinforcement lowering portion 321 is positioned behind the rib cage 91 of the occupant 9, the first side piece 61 of the pressure receiving member 4 exerts a reaction force against the rib cage 91 that tends to be displaced when the vehicle turns. can give. The seat back 11 can effectively suppress changes in the posture of the occupant 9 .

Since the side pieces 61 to 67 extend outward and forward in the width direction from the base portion 69, the first side piece 61 exerts a reaction force on a portion from the side of the back of the occupant 9 to the side of the body of the occupant 9. can give. The seat back 11 can effectively suppress changes in the posture of the occupant 9 in the direction in which the rib cage 91 rotates and/or in the direction in which the rib cage 91 tilts left and right.

In addition, the non-woven fabric as the reinforcing member 32 controls the amount of compression of the foam member 31, so that the vehicle seat back 11 appropriately supports the back of the occupant 9 and improves riding comfort. The notch as the reinforcement lowering portion 321 formed in the nonwoven fabric does not constrain the rear surface of the foam member 31, so that the reaction force when a local load is input from the back of the occupant 9 is reduced. As a result, as described above, the lower reinforcement portion 321 initially reduces the reaction force on the back of the occupant 9 with respect to the local load input when the vehicle turns, and then the pressure receiving member 4, mainly the first The side piece 61 can apply a sufficient reaction force to the back of the occupant 9 and suppress the change in the posture of the occupant 9 .

Note that the reinforcement lowering portion 321 is not limited to the notch, and may be a cut formed in the reinforcing member 32 as illustrated in FIG. 9, for example. Although the cut in FIG. 9 is in a U-shape that is laid down sideways, the cut may be in an L-shape, for example. As with the notch, the cut also releases the restraint of the rear surface of the foam member 31 by the reinforcing member 32 . Therefore, as described above, the reaction force on the back of the occupant 9 is initially reduced with respect to the local load input when the vehicle turns. sufficient reaction force can be applied to the occupant 9, and the change in posture of the occupant 9 can be suppressed.

1 Vehicle seat back 2 Frame (seat back frame)
4 pressure receiving member 6 main body 60 side piece 68 fixing portion 69 base portion 7 rigid member 8 connecting member 9 occupant 91 thorax

Claims (5)

a seat back frame;
a pressure receiving member positioned within the seat back frame and receiving a load from the back of the occupant;
a connecting member that connects the pressure receiving member to the seat back frame;
The pressure receiving member has a main body and a rigid member fixed to the rear side of the main body at a position corresponding to the occupant's ribcage,
The seatback for a vehicle, wherein the rigid member extends in the width direction of the seatback, and a plurality of positions at different positions in the width direction are connected to the seatback frame by the connecting member. In the vehicle seat back according to claim 1,
The main body has a base located in the center in the width direction of the seat back, and a plurality of side pieces extending outward in the width direction from both sides of the base,
a connection point between the rigid member and the connecting member is on the central side corresponding to the position of the base;
The vehicle seatback, wherein the rigid member is fixed to the base portion on the central side of the connecting portion. In the vehicle seat back according to claim 2,
The vehicle seat back, wherein the rigid member extends outward from the tip of the side piece. In the vehicle seat back according to claim 2 or 3,
In the vehicle seatback, the rigid member has a higher rigidity outside the position of the connecting member than inside the position of the connecting member. In the vehicle seat back according to any one of claims 1 to 4,
The vehicle seat back, wherein the base portion is located above the position of the side piece and has a fixing portion fixed to the rigid member.