JP2023157032A - vehicle seat - Google Patents

Abstract

To reduce whiplash injury in an event of rear-end collision.SOLUTION: In a vehicle seat 10, a whiplash injury reduction mechanism 50 is provided on a cross member 38. Therefore, when a seated occupant P moves toward a rear side in an event of a rear-end collision, an impact load F toward the rear side is input to a lengthwise central part of the cross member 38 via a support plate 52, the cross member 38 bends and deforms with a low-rigidity portion 38A as a starting point, and the lengthwise central portion of the cross member 38 and the support plate 52 are displaced toward the rear side. Therefore, a lumbar region P2 of the seated occupant P is suppressed from riding over the cross member 38, and the lumbar region P2 of the seated occupant P is maintained at a position displaced toward the rear side. Accordingly, the upper body of the seated occupant P can be suppressed from sliding up toward an upper-end side of the seat back 30 along the seat back 30. Therefore, bending of the upper body of the seated occupant P toward the rear side, caused by the upper body of the seated occupant P sliding up, can be suppressed and bending of the neck of the seated occupant P can be suppressed.SELECTED DRAWING: Figure 4

Description

The present invention relates to a vehicle seat.

In the vehicle seat described in Patent Document 1, a chest support means is provided at the upper part of the seat back, and a pelvis upper support means is provided at the lower part of the seat back. In the event of a rear-end collision of a vehicle, the movement of the seated occupant's lumbar region to the rear is restricted by the upper pelvis support means, and the chest support means moves rearward, allowing the seated occupant to move to the rear of the chest. Ru. That is, in the event of a rear-end collision of the vehicle, only the chest support means moves, and the seated occupant's upper body tilts backward using the pelvis as a fulcrum. Thereby, the amount of movement of the seated occupant's head during a rear collision can be increased. As a result, the gap between the head of the seated occupant and the headrest can be reduced.

Japanese Patent Application Publication No. 10-181400

However, the above vehicle seat has room for improvement in the following points. That is, in the above vehicle seat, as described above, the movement of the seated occupant's lumbar region to the rear side is restricted by the pelvis upper support means, and the seated occupant's upper body tilts backward using the pelvic region as a fulcrum. . At this time, the seated occupant's upper body may curve rearward and slide upward along the seat back, and the seated occupant's head may protrude above the headrest. In this case, the ability of the headrest to support the head of the seated occupant is reduced, and the weight of the head bends the neck of the seated occupant rearward, potentially causing whiplash injury to the seated occupant.

The present invention has been made in consideration of the above facts, and an object of the present invention is to provide a vehicle seat that can reduce whiplash injuries in the event of a rear collision.

One or more embodiments of the present invention include a seat back that supports the back of a seated occupant, a pair of side frames provided on both sides of the seat back in the seat width direction, and a pair of side frames extending in the seat width direction, a cross member that spans the pair of side frames and supports the waist of a seated occupant; the cross member constitutes both sides in the longitudinal direction of the cross member, and is a pair of low-rigidity parts having low rigidity; and a support part formed in a plate shape with the thickness direction in the front-rear direction of the seat, connected to the front part of the cross member, and disposed between the pair of low-rigidity parts. A vehicle seat having:

According to one or more embodiments of the present invention, whiplash injuries during rear-end collisions can be reduced.

FIG. 1 is a side view schematically showing the inside of a cabin of a vehicle to which the vehicle seat according to the present embodiment is applied, as viewed from the right side of the vehicle. FIG. 2 is a front view of the vehicle seat shown in FIG. 1 as seen from the front side of the vehicle. FIG. 3 is a side view of the right vehicle seat shown in FIG. 2, seen from the left side. FIG. 3 is a cross-sectional view (cross-sectional view taken along line 4-4 in FIG. 2) of the inside of the seat back of the right vehicle seat shown in FIG. 2 when viewed from above. FIG. 3 is an explanatory diagram for explaining the behavior of a seated occupant during a rear-end collision of a vehicle. FIG. 3 is a side view seen from the left side for explaining the operation of the whiplash injury reduction mechanism at the time of a rear collision of the vehicle.

Hereinafter, a vehicle seat 10 according to the present embodiment will be described using the drawings. Note that the arrow FR shown as appropriate in the drawings indicates the front side of the vehicle seat 10, the arrow UP indicates the upper side of the seat, and the arrow RH indicates the right side of the seat (one side in the seat width direction). In the following description, when the vertical, longitudinal, and horizontal directions are used, unless otherwise specified, the vertical direction of the seat, the longitudinal direction of the seat, and the horizontal direction of the seat are meant. Further, the upper side of the seat, the front side of the seat, and the right side of the seat correspond to the upper side of the vehicle, the front side of the vehicle, and the right side of the vehicle, respectively, of the vehicle (automobile) V to which the vehicle seat 10 is applied.

As shown in FIG. 1, the vehicle seat 10 is configured as a rear seat disposed at the rear inside a cabin C of a vehicle V. As shown in FIG. 2, the vehicle seats 10 are arranged at the left and right parts of the rear part of the cabin C, respectively, and the left and right vehicle seats 10 are configured symmetrically.

The vehicle seat 10 includes a seat cushion 20 that supports the buttocks and thighs of the seated occupant P, a seat back 30 that supports the back of the seated occupant P, and a headrest 40 that supports the head P1 of the seated occupant P. It is composed of .

As shown in FIGS. 2 and 3, the seat cushion 20 is arranged above the floor panel of the vehicle V and is fixed to the floor panel. A seat cushion frame 21 that constitutes a skeleton of the seat cushion 20 is provided inside the seat cushion 20. The seat cushion frame 21 has a pair of left and right cushion-side side frames 22, and the cushion-side side frames 22 are formed in a substantially elongated plate shape extending in the front-rear direction with the seat width direction as the plate thickness direction. They are arranged on both sides of the seat cushion 20 in the seat width direction. A front frame (not shown) spans between the front ends of the pair of cushion-side side frames 22, and the front ends of the cushion-side side frames 22 are connected to each other by the front frame. The rear end portions of the pair of cushion-side side frames 22 extend upward and are connected to a back-side side frame 32, which will be described later.

The seat back 30 is arranged in an upright state above the rear end portion of the seat cushion 20. A seat back frame 31 that constitutes a skeleton of the seat back 30 is provided inside the seat back 30. The seat back frame 31 includes a back side frame 32 as a pair of left and right side frames, a lower frame 33, an upper frame 35, and a cross member 38.

The back-side side frames 32 are formed in a substantially elongated plate shape with the seat width direction as the plate thickness direction and extending in the vertical direction, and are disposed on both sides of the lower part of the seat back 30 in the seat width direction. The rear end portion of the cushion-side side frame 22 described above is connected to the lower end portion of the back-side side frame 32. The lower frame 33 is made of pipe material and extends along the seat width direction. The lower frame 33 is disposed below the pair of left and right back side frames 32 , and both longitudinal ends of the lower frame 33 are connected to the lower ends of the back side frames 32 by side brackets 34 .

The upper frame 35 is made of a pipe material, and is bent into a substantially inverted U-shape that is open downward when viewed from the front. Both ends of the upper frame 35 in the longitudinal direction are arranged inside the upper end of the back side frame 32 in the seat width direction, and are connected to the back side frame 32 by bonding or the like. A pair of left and right support brackets 36 are provided on the front side of the upper end of the upper frame 35 at the middle portion in the seat width direction. The support bracket 36 is formed into a substantially rectangular cylindrical shape with the vertical direction as the axial direction, and the upper end portion of the support bracket 36 is connected to the upper end portion of the upper frame 35 by bonding or the like. The support bracket 36 is provided with a headrest support 37 that supports a headrest, which will be described later.

The cross member 38 is formed into a substantially round bar shape extending in the seat width direction. The cross member 38 is arranged above the lower frame 33 and between the pair of left and right back side frames 32, and both longitudinal ends of the cross member 38 are fixed to the upper part of the cushion side frame 22. . The cross member 38 is arranged on the rear side of the waist P2 of the seated occupant P. Specifically, the position of the cross member 38 in the vertical direction is set so that the upper part of the pelvis of the seated occupant P presses the cross member 38 rearward in the event of a rear collision of the vehicle V. In this embodiment, the seated occupant P seated on the vehicle seat 10 is a dummy doll of AM50 (50th percentile of American adult males).

The headrest 40 is provided at the center of the upper end of the seatback 30 in the seat width direction, and protrudes upward from the seatback 30. Inside the headrest 40, a stay 41 having a substantially long bar shape is provided. The stay 41 is bent into a substantially inverted U-shape that is open downward when viewed from the front, and both longitudinal ends of the stay 41 protrude downward from the headrest 40 . Both ends of the stay 41 in the longitudinal direction are inserted into the headrest support 37 of the seat back 30 from above, so that the headrest 40 is supported by the seat back 30.

As shown in FIGS. 2 to 4, the cross member 38 of the seat back 30 described above is provided with a structure that reduces whiplash injuries by reducing the load on the neck of the seated occupant P in the event of a rear-end collision of the vehicle V. An injury reduction mechanism 50 is provided. The whiplash injury reduction mechanism 50 includes a pair of left and right low-rigidity parts 38A formed on the cross member 38, and a support plate 52 as a support part.

The pair of left and right low-rigidity portions 38A are provided on both sides of the cross member 38 in the longitudinal direction. The cross-sectional area of the section 38B is set smaller than that of the section 38B. Specifically, a notch 38C (see FIG. 4) is formed in the cross member 38 at a portion where the low-rigidity portion 38A is provided, and the notch 38C is formed in a concave shape that is open to the front side. In addition, it is curved in a substantially semicircular shape when viewed from above. Thereby, the rigidity of the low-rigidity portion 38A is set lower than the rigidity of the general portion 38B. The low-rigidity portion 38A is located on the rear side of both sides in the width direction of the pelvic region of the seated occupant P. When a rear impact load is input from the seated occupant P to the cross member 38 during a rear collision of the vehicle V, the cross member 38 is bent and deformed starting from the low rigidity portion 38A, and the cross member 38 is bent in the longitudinal direction. The mechanical strength of the low-rigidity portion 38A is set so that the central portion is displaced rearward (see the cross member 38 indicated by the two-dot chain line in FIG. 4).

The support plate 52 is formed into a substantially rectangular plate shape whose thickness direction is the front-rear direction. The support plate 52 is arranged in front of the longitudinal center of the cross member 38, and the upper end of the support plate 52 is connected to the cross member 38 by joining or the like. That is, the support plate 52 is arranged between the pair of left and right low-rigidity parts 38A, and the lower part of the support plate 52 protrudes downward from the cross member 38. Then, when an impact load to the rear side is input from the seated occupant P to the support plate 52 at the time of a rear collision of the vehicle V, the low rigidity portion 38A of the cross member 38 is twisted and deformed by the support plate 52. The mechanical strength is set at 38A.

(effect)
Next, while explaining the behavior of the seated occupant P at the time of a rear collision of the vehicle V, the operation and effects of this embodiment will be explained.

As shown in the upper diagram of FIG. 5, in the sitting posture of the seated occupant P, the upper body of the seated occupant P is located above the buttock. Located near the top of Therefore, a downward load due to the body weight mainly acts on the rear part of the seat cushion 20 from the buttocks of the seated occupant P (see arrow G in the upper diagram of FIG. 5). In the event of a rear collision of the vehicle V, the seated occupant P moves rearward with respect to the vehicle seat 10 due to inertia force. As a result, at the initial stage of a rear collision, the impact load F to the rear mainly acts on the lower part of the seat back 30 from the seated occupant P. For this reason, an impact load F acts on the lower end of the seat back 30 from the waist P2 (pelvis) of the seated occupant P. Specifically, the impact load F acts on the cross member 38 of the seat back 30.

Here, in the cross member 38 of the vehicle seat 10, if the whiplash injury reduction mechanism 50 (low rigidity portion 38A and support plate 52) is omitted, the rigidity of the cross member 38 will be increased. Therefore, even if a rearward impact load F is input to the cross member 38, deformation of the cross member 38 is suppressed. As a result, as shown in the lower diagram of FIG. 5, the waist P2 of the seated occupant P rides on the cross member 38, and the upper body of the seated occupant P slides up along the seatback 30 toward the upper end of the seatback 30. It becomes like this. Specifically, the upper body of the seated occupant P shown by the solid line in the bottom view of FIG. 5 slides up, and changes to the upper body of the seated occupant P shown by the two-dot chain line. Furthermore, when the upper body of the seated occupant P slides up toward the upper end of the seat back 30, a rearward impact load F acts from the upper body of the seated occupant P to the upper portion of the seat back 30 as well. As a result, the seat back 30 is tilted rearward with respect to the seat cushion 20.

When the upper body of the seated occupant P moves toward the upper end of the seat back 30 along the seat back 30 and the seat back 30 tilts backward, the upper body of the seated occupant P begins to warp rearward. As a result, the head P1 of the seated occupant P is displaced to rotate rearward (in the direction of arrow A in the lower diagram of FIG. 5) around the neck (as indicated by the dashed line in the lower diagram of FIG. 5). (See the head P1 of the seated occupant P). That is, by displacing the head P1 of the seated occupant P, the neck of the seated occupant P is bent. Further, at this time, since the upper body of the seated occupant P is shifted toward the upper end of the seat back 30, the head of the seated occupant P is displaced toward the upper side of the headrest 40. As described above, if the low-rigidity portion 38A and the support plate 52 are omitted in the cross member 38 of the vehicle seat 10, the headrest 40 will function to support the head of the seated occupant P in the event of a rear collision of the vehicle V. This may cause a whiplash injury to the seated occupant P.

In contrast, in the vehicle seat 10 of this embodiment, the cross member 38 is provided with a whiplash injury reduction mechanism 50. Therefore, as shown in FIGS. 4 and 6, when the seated occupant P moves rearward due to inertia force at the initial stage of a rear collision of the vehicle V, the impact load F to the rear side is applied to the cross member via the support plate 52. 38 in the longitudinal center. As a result, the cross member 38 bends and deforms starting from the low-rigidity portion 38A, and the longitudinal center portion of the cross member 38 and the support plate 52 are displaced rearward (as indicated by the two-dot chain line in FIGS. 4 and 6). (See cross member 38 and support plate 52 shown).

In addition, the support plate 52 has a lower end portion that protrudes below the cross member 38. Therefore, when an impact load F to the rear side is input to the support plate 52, the support plate 52 rotates counterclockwise (in the direction of arrow B in FIG. 6) around the cross member 38 when viewed from the left side. The low-rigidity portion 38A twists and deforms as it moves. As a result, the support plate 52 is tilted rearward as it goes downward in side view (see the support plate 52 indicated by a two-dot chain line in FIG. 6), and a part of the waist P2 of the seated occupant P is The angle of the waist portion P2 of the seated occupant P is changed such that the lower back portion P2 of the seated occupant P is located below the longitudinal center portion of the cross member 38. As a result, the position of the waist P2 of the seated occupant P displaced rearward is maintained by the cross member 38 and the support plate 52.

As described above, according to the vehicle seat 10 of the present embodiment, in the event of a rear collision, the lumbar region P2 of the seated occupant P displaced to the rear side is maintained at that position, and the upper body of the seated occupant P is moved toward the seat back 30. It is possible to suppress the seat back 30 from sliding up along the upper end side. Thereby, it is possible to suppress the rearward bending of the seated occupant's P's upper body, which is caused by the seated occupant's P's upper body sliding up, and it is also possible to suppress the bending of the seated occupant's neck. Further, at this time, since the seated occupant P is prevented from sliding up, the state in which the head P1 of the seated occupant P is located in front of the headrest 40 is maintained. Therefore, the head P1 of the seated occupant P can be supported from the rear side by the headrest 40. As described above, according to the vehicle seat 10 of the present embodiment, whiplash injuries in the event of a rear collision can be reduced.

Further, in this embodiment, as described above, the support plate 52 is provided in the longitudinal center of the cross member 38 in the shape of a substantially rectangular plate whose thickness direction is the front-rear direction. As a result, in the event of a rear collision, the support plate 52 efficiently receives the lumbar region P2 of the seated occupant P, and the impact load F acting on the seat back 30 from the seated occupant P is effectively transferred to the longitudinal center portion of the cross member 38 by the support plate 52. can be transmitted to. Therefore, the cross member 38 can be suitably bent and deformed at the low-rigidity portion 38A, and the longitudinal center portion of the cross member 38 can be displaced rearward.

Furthermore, by providing the support plate 52 at the longitudinal center of the cross member 38, the longitudinal center of the cross member 38 can be reinforced by the support plate 52. As a result, it is possible to suppress bending deformation of the longitudinal center portion of the cross member 38 in the event of a rear collision, and to better bend and deform the cross member 38 at the low-rigidity portion 38A.

Further, the support plate 52 protrudes downward from the cross member 38. Therefore, when the impact load F is input to the support plate 52 at the time of a rear collision, the support plate 52 can generate a rotational moment in the longitudinal center of the cross member 38 . Thereby, the cross member 38 can be torsionally deformed and the support plate 52 can be tilted. Specifically, the support plate 52 tilts rearward as it goes downward in side view. As a result, the angle of the waist P2 of the seated occupant P is changed such that a portion of the waist P2 of the seated occupant P is located below the longitudinal center of the cross member 38. Therefore, the position of the waist P2 of the seated occupant P displaced rearward can be effectively maintained by the support plate 52. As a result, it is possible to effectively suppress the upper body of the seated occupant P from shifting toward the upper end along the seat back 30.

Further, the cross member 38 is composed of a single member, and the cross-sectional area of the low-rigidity portion 38A is set smaller than the cross-sectional area of the general portion 38B. That is, by forming the cutout portion 38C in the cross member 38, the low rigidity portion 38A can be provided in the cross member 38. Therefore, the configuration of the cross member 38 can be simplified, and it is possible to contribute to cost reduction of the vehicle seat 10.

Note that in this embodiment, the cross member 38 is constructed from a single member. Alternatively, the cross member 38 may be formed by configuring the low-rigidity portion 38A and the general portion 38B as separate members and connecting them.

Further, in this embodiment, an example is shown in which the whiplash injury reduction mechanism 50 is applied to the rear seats of the vehicle V, but the whiplash injury reduction mechanism 50 may also be applied to the front seats of the vehicle V. .

10 Vehicle seat 30 Seat back 32 Back side frame (side frame)
38 Cross member 38A Low rigidity part 52 Support plate (support part)

Claims (3)

a seat back that supports the back of a seated passenger;
a pair of side frames provided on both sides of the seat back in the seat width direction;
a cross member that extends in the seat width direction, spans the pair of side frames, and supports the lumbar region of the seated occupant;
Equipped with
The cross member is
a pair of low-rigidity portions that constitute both sides in the longitudinal direction of the cross-member and have lower rigidity than other portions of the cross-member;
a support part formed in a plate shape with the thickness direction in the front-rear direction of the seat, connected to the front part of the cross member, and disposed between the pair of low-rigidity parts;
A vehicle seat with The vehicle seat according to claim 1, wherein the support portion protrudes below the seat with respect to the cross member. 3. The vehicle seat according to claim 1, wherein the cross member is made of a single member, and the cross-sectional area of the low-rigidity portion is smaller than the cross-sectional area of other parts of the cross member.

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