JP7647659B2 - Vehicle seat - Google Patents

Description

The present invention relates to a vehicle seat.

Patent document 1 discloses a vehicle seat equipped with an escape mechanism at the front of the seat cushion that rotates in the fore-and-aft direction of the vehicle. In this document, the escape mechanism and the upper end of the seatback are connected by a planar body that extends along the seating surface, so that the escape mechanism rotates rearward in conjunction with the reclining of the seatback, making it difficult for the back to shift when the seatback tilts.

JP 2019-010976 A

As described above, the vehicle seat described in Patent Document 1 has the effect of suppressing back slippage caused by tilting the seat back. Meanwhile, in vehicles equipped with an automatic driving function, it is expected that in the future, when the vehicle is automatically driven, a comfortable position (reclined position) with the seat back tilted backward will be more common. However, Patent Document 1 does not take into consideration the submarine phenomenon that occurs when a vehicle crashes (frontal collision) in a comfortable position, that is, when an impact is received in a collision accident, the occupant breaks free from the restraints of the seat belt, slides off the seat, and slides under the dashboard, etc., and there is room for improvement in terms of measures against the submarine phenomenon in a frontal collision in a comfortable position.

The present invention takes the above into consideration and aims to provide a vehicle seat that prevents the back from shifting when the occupant is in a comfortable position and suppresses the occurrence of the submarine phenomenon during a frontal collision.

The vehicle seat according to the present invention described in claim 1 includes a seat cushion having a submarine prevention part at the front and on which an occupant sits, a seat back erected from the rear part of the seat cushion and constituting a backrest for the occupant seated on the seat cushion, a reclining mechanism that rotates around a reclining center and adjusts the angle of the seat back relative to the seat cushion, a rotation device that rotates in conjunction with the reclining action of the reclining mechanism, a shape-deforming body that is disposed in the rear region of the seat cushion and forward of the rotation device, and a moving part that, when the seat back is tilted backward by the reclining mechanism, is wound up by the rotation device that rotates in conjunction with the reclining action and moves toward the rear of the seat, thereby deforming the deforming body toward the rear and upper part of the seat.

In the vehicle seat according to the present invention described in claim 1, when the seat back is tilted backward by the reclining mechanism, the rotating device rotates in conjunction with this reclining action. The rotating rotating device then winds up the moving part, which moves the moving part toward the rear of the seat and deforms the shape-deformable deformation body, which is disposed in the rear region of the seat cushion and in front of the rotating device, toward the rear and upper part of the seat. That is, the deformation body is deformed toward the rear and upper part of the seat by the moving part. The deformation of this deformation body lifts the rear region of the seat cushion, so that the hip point of the occupant seated on the seat cushion is raised. This reduces the change in the distance from the headrest to the hip point when the seat back is reclined, thereby suppressing back slippage.

In addition, by raising the hip point, the lap belt anchor is relatively lowered, allowing the lap belt anchor to be positioned lower, which is advantageous in preventing the occurrence of the submarine phenomenon during a frontal collision. In addition, the deformed body can raise the pelvic angle of the occupant, improving the fit between the lap belt and the occupant's ilium, and improving the restraint performance of the occupant's lower back. As a result, it is possible to prevent the occurrence of the submarine phenomenon during a frontal collision in a comfortable posture.

As described above, the vehicle seat according to the present invention has the excellent effect of preventing the back from shifting when the occupant is in a comfortable position and suppressing the occurrence of the submarine phenomenon in the event of a frontal collision.

1 is a side cross-sectional view of a vehicle seat according to an embodiment of the present invention in a normal position; 1 is a side cross-sectional view of a vehicle seat according to an embodiment of the present invention in a comfortable position; 1A is an enlarged side view of a reclining mechanism and a rotating device in a normal position, and FIG. 1A is an enlarged side view of a reclining mechanism and a rotating device in a comfortable position, and FIG. 2 is an enlarged cross-sectional side view of a seat cushion of the vehicle seat of FIG. 1 . 3 is an enlarged side cross-sectional view of a seat cushion of the vehicle seat of FIG. 2.

Below, a vehicle seat 10 according to one embodiment of the present invention will be described with reference to the attached drawings. In this specification and the drawings, components having substantially the same functional configuration are denoted with the same reference numerals to avoid repetitive description. The arrows UP, FR, LH, and RH shown as appropriate in each drawing respectively indicate the upward direction, forward direction, leftward direction, and rightward direction in the left-right direction (vehicle width direction) of the vehicle seat 10 mounted on the vehicle. In the following, when the directions of front-rear, left-right, and up-down are used in the description, they refer to the front-rear direction in the front-rear direction, the left-right direction in the left-right direction (vehicle width direction), and the up-down direction in the up-down direction of the vehicle seat 10 mounted on the vehicle, unless otherwise specified.

(Configuration of vehicle seat)
The vehicle seat 10 of this embodiment is a seat installed in a vehicle (e.g., an automobile, a train, etc.), and is, as an example, an 8-way power seat with functions for adjusting the seat forward/backward, the seat height, the reclining, and the inclination of the seat cushion. In this embodiment, the vehicle seat 10 is, as an example, a seat on the left side of the front seat of the vehicle. As shown in Fig. 1, the vehicle seat 10 includes a seat cushion 12 on which an occupant sits (supporting the occupant's buttocks and thighs), a seat back 14 that supports the occupant's back, i.e., forms a backrest, and a headrest 16 that supports the occupant's head.

The seat cushion 12 includes a cushion pad 18, a seat pan 20, and a seat cover (not shown).

The cushion pad 18 constitutes the seat surface of the vehicle seat 10 and is made of, for example, a synthetic resin material having elasticity, such as polyurethane foam (polyurethane foam). The occupant sits on the upper side (seat surface) of the seat cushion 12. The cushion pad 18 also has a submarine prevention portion 22 on the underside of the front part of the cushion pad 18.

The submarine prevention portion 22 is a member for preventing an occupant seated in the vehicle seat 10 from sliding off the vehicle seat 10 during a frontal collision, and is, for example, made of a material harder than the cushion pad 18. Specifically, it is formed integrally with the cushion pad 18 from a synthetic resin material such as polyurethane foam (foamed polyurethane).

The seat pan 20 is a frame that forms the skeleton of the seat cushion 12, and has a recess 20A on top of which the cushion pad 18 is placed. The seat cover is made of a flexible sheet material such as cloth, leather, or synthetic leather. The seat cushion 12 is constructed by attaching the cushion pad 18 to the recess 20A of the seat pan 20, and then covering its surface with the seat cover.

The seat back 14 constitutes the backrest of the vehicle seat 10, and the front side (seat surface) of the seat back 14 supports the back of an occupant seated on the seat cushion 12. The seat back 14 includes a seat back frame 26, a seat back pad 28, and a seat cover.

The seatback frame 26 forms the framework of the seatback 14. The seatback pad 28 is formed of, for example, an elastic synthetic resin material such as polyurethane foam (polyurethane foam). The seat cover is formed of a flexible sheet material such as cloth, leather, or synthetic leather. The seatback 14 is formed by attaching the seatback pad 28 to the seatback frame 26 and further covering the surface with the seat cover.

The vehicle seat 10 also includes a reclining mechanism 40. The reclining mechanism 40 is a known mechanism that rotates the seat back 14 around a reclining center C to adjust the angle of the seat back 14 relative to the seat cushion 12. As an example, the reclining mechanism 40 uses an electric actuator to transmit force to the seat back frame 26, thereby rocking the seat back frame 26 in the front-rear direction relative to the seat pan 20.

In this embodiment, as shown in FIG. 1, the normal position is a state in which the seat back 14 is tilted backward by the reclining mechanism 40 so that the angle R between the floor 100 of the vehicle (not shown) and the seat back 14 is, for example, approximately 45° to 90°. That is, the normal position is a state in which the seat back 14 is tilted backward by 0° to 45° in the up-down direction (vertical direction). Also, as shown in FIG. 2, the comfortable position (reclining position) is a state in which the seat back 14 is tilted backward by the reclining mechanism 40 so that the angle R between the floor 100 of the vehicle (not shown) in which the vehicle seat 10 is mounted and the seat back 14 is, for example, approximately 30° to 45°. That is, the comfortable position is a state in which the seat back 14 is tilted backward by, for example, approximately 45° to 60° in the up-down direction.

The vehicle seat 10 also includes a rotation device 50 that is disposed above and in front of the reclining center C and rotates in conjunction with the reclining action of the reclining mechanism 40, and a moving part 60 that is wound up by the rotation device 50.

As shown in Figures 3 and 4, the rotating device 50 has a first rotating shaft 52 that passes through insertion holes (not shown) provided in the left wall portion 20L and the right wall portion 20R that are erected from the bottom surface in the left-right direction of the seat pan 20, and is rotatably supported by the left wall portion 20L and the right wall portion 20R. A first rotating gear 54 is fixed to the first rotating shaft 52 on the inside (left side) of the right wall portion 20R in the width direction, as a sprocket that rotates integrally with the first rotating shaft 52.

On the other hand, a second rotating shaft 42 that passes through the left side frame 26L and the right side frame 26R is fixed to the left side frame 26L and the right side frame 26R of the seatback frame 26. The left wall portion 20L and the right wall portion 20R are disposed on the outside of the left side frame 26L and the right side frame 26R in the width direction, respectively, and the left wall portion 20L and the right wall portion 20R rotatably support the second rotating shaft 42. In other words, the seatback frame 26 (left side frame 26L and right side frame 26R) rotates together with the second rotating shaft 42 that is supported and rotated by the left wall portion 20L and the right wall portion 20R, so that the central axis of the second rotating shaft 42 becomes the reclining center C of the reclining mechanism 40.

In addition, a second rotating gear 44 serving as a sprocket is fixed to the second rotating shaft 42 on the inside (left side) of the right side frame 26R in the width direction, and the rotating gear 44 rotates integrally with the second rotating shaft 42.

As shown in Figures 3(a) and 4(a), a single chain 58 is wound around the outer periphery of the first rotating gear 54 and the second rotating gear 44, and the first rotating gear 54 rotates integrally with the first rotating shaft 52 in accordance with the rotation of the second rotating gear 44.

A bobbin 56 extending in the width direction is fixed to the first rotating shaft 52 in the center in the left-right direction, to the left of the first rotating gear 54. In other words, the first rotating shaft 52, the first rotating gear 54, and the bobbin 56 rotate together in conjunction with the reclining operation of the reclining mechanism 40.

The rear of the air bag 70, which will be described later, and the left and right strap ends 64L and 64R of the strap 64, which will be described later, are fixed to the bobbin 56. In conjunction with the reclining operation, the first rotating gear 54 rotates together with the second rotating gear 44, and the bobbin 56 rotates together with the first rotating shaft 52 in a direction that winds up the rear of the air bag 70, the left and right strap ends 64L and 64R, and winds up the rear of the air bag 70, the left and right strap ends 64L and 64R. The amount of winding of the rear of the air bag 70, the left and right strap ends 64L and 64R can be adjusted by the gear ratio between the first rotating gear 54 and the second rotating gear 44, and the diameter of the bobbin 56.

In this embodiment, the rotation device 50 is composed of a first rotating shaft 52, a second rotating shaft 42, a first rotating gear 54, a second rotating gear 44, a bobbin 56, and a chain 58.

On the other hand, the left end 64L and the right end 64R of the strap 64 are fixed to the bobbin 56 as described above. Also, as shown in FIG. 3, the center portion 64F of the strap 64 is located in front of the seat and is fixed to the air bag 70 as a deformable body described below, so as to surround the air bag 70 from the front end side. Note that it is sufficient that at least a portion of the front end side of the strap 64 and the air bag 70 is fixed.

The air bag 70 is a bag filled with air and sealed, and has an internal pressure that allows it to deform. The rear end of the air bag 70 is fixed to the bobbin 56 together with the left strap end 64L and the right strap end 64R. Note that in Figures 3 and 4, both sides of the front end of the strap 64 are shown as having corners, but in reality, they are shaped to match the shape of the air bag 70. Also, there are gaps on both sides of the width between the strap 64 and the air bag 70, but as long as the air bag 70 is capable of deforming, there may or may not be a gap, and there is no particular limitation.

As shown in FIG. 1, in this embodiment, the air bag 70 is disposed inside the cushion pad 18, and is placed on a mounting portion 62 that is also disposed inside the cushion pad 18 and provided on the rear end side of the recess 20A of the seat pan 20. The mounting portion 62 is made of a material that is hard enough to at least withstand the weight of the occupant, and as an example, is made of the same material as the seat pan 20. The mounting portion 62 has a slight recess at the top to limit the movement of the air bag 70.

In this embodiment, the cushion pad 18 has a mounting portion 62, an air bag 70 mounted on the mounting portion 62, and a strap 64 fixed to the air bag 70 disposed therein, and the rear of the air bag 70, as well as the left end 64L and the right end 64R of the strap 64 extend outside the cushion pad 18 and are fixed to the bobbin 56. In this embodiment, the mounting portion 62 and the strap 64 are the moving portion 60 that deforms the air bag 70.

(Functions and Effects of the Embodiments)
Next, the operation and effects of the vehicle seat 10 according to the present embodiment configured as above will be described.

In the vehicle seat 10 according to this embodiment, the seat back 14 is reclined by the reclining mechanism 40. That is, the seat back 14 rotates around the reclining center C together with the second rotation shaft 42 and is tilted backward from the normal position shown in FIG. 1 to the comfortable position (reclined position) shown in FIG. 2.

In conjunction with this reclining movement, the rear of the air bag 70, as well as the left end 64L and the right end 64R of the strap 64 are wound onto the bobbin 56 by the rotating device 50. Specifically, as the right side frame 26R of the seatback frame 26 tilts backward, the second rotating gear 44 fixed to the second rotating shaft 42 rotates, and the first rotating gear 54 also rotates via the chain 58. In addition, as the first rotating gear 54 rotates, the first rotating shaft 52 to which the first rotating gear 54 is fixed and the bobbin 56 fixed to the first rotating shaft 52 rotate.

The bobbin 56 is rotated in a direction that winds up the left and right strap ends 64L and 64R, as well as the rear of the air bag 70. This causes the strap 64 to move from the normal position shown in FIG. 3 to the comfortable position shown in FIG. 4. That is, the left and right strap ends 64L and 64R of the strap 64 are wound by the rotating device 50, and the center portion 64F of the strap 64 moves toward the rear of the seat as shown in FIG. 4.

As a result, when the air bag 70 is placed in the recess of the mounting portion 62 (in the normal position) as shown in Figs. 1 and 5, the front end of the air bag 70 is pressed backward by the center portion 64F of the strap 64. At this time, the rear of the air bag 70 is wound up by the rotating device 50, adjusting the internal pressure to high pressure, and since the mounting portion 62 is made of a hard material as described above, the air bag 70 is deformed backward and upward as shown in Figs. 2 and 6. As a result, the cushion pad 18 is lifted as shown in Fig. 6, and the lower back of the occupant seated on the cushion pad 18, i.e., the hip point HP, is raised as shown in Fig. 2.

By raising the hip point HP in this way, the difference between the distance L1 from the center O of the headrest 16 to the hip point HP in the normal posture shown in Figure 1 and the distance L2 from the center O of the headrest 16 to the hip point HP in the comfortable posture shown in Figure 2 can be reduced, thereby preventing the back from slipping.

In addition, by raising the hip point HP, the height H2 from the lap belt anchor A to the hip point HP in the relaxed position shown in FIG. 5 can be made higher than the height H1 from the lap belt anchor A to the hip point HP in the normal position shown in FIG. 1, so the lap belt anchor A can be relatively lowered. This allows the lap belt anchor A to be positioned lower, which is advantageous for preventing the submarine phenomenon from occurring during a frontal collision.

In addition, by deforming the air bag 70 upward, the angle of the occupant's pelvis can be made more upright, improving the fit between the lap belt and the occupant's ilium, thereby enhancing the ability of the lap belt to restrain the occupant's lower back.

As a result, the vehicle seat 10 of this embodiment can suppress the submarine phenomenon during a frontal collision when the occupant is in a comfortable position.

Furthermore, the air bag 70 and the rotating device 50 are configured to wind up in conjunction with the reclining movement of the seat back 14, so they can be used repeatedly, unlike configurations that use inflators that burn gunpowder to generate high-pressure gas.

In the above embodiment, the rotating device 50 is configured to use the first rotating gear 54 and the second rotating gear 44 as sprockets and the chain 58, but the present invention is not limited to this. The rotating device 50 may be configured to use a pulley and a belt. Also, the rotating device 50 may be configured such that the first rotating gear 54 and the second rotating gear 44 are configured as gears, and are arranged so that the first rotating gear 54 and the second rotating gear 44 directly mesh with each other.

In the above embodiment, the submarine prevention unit 22 is made of a synthetic resin material such as polyurethane foam (polyurethane foam), but the present invention is not limited to this. For example, the submarine prevention unit 22 may be a known seat cushion airbag.

In the above embodiment, the moving part 60 is configured to use one strap 64, but the present invention is not limited to this. For example, the central part 64F fixed to the air bag 70 may be a belt wider than the strap 64, with a strap 64 connected to each end of the belt, and the straps 64 on both sides wound up by the rotating device 50. In other words, it is sufficient that the bobbin 56 of the rotating device 50 can be configured to wind up at least a length that ensures the amount of movement that can transform the air bag 70 to the target height.

In addition, in the above embodiment, the moving unit 60 is configured to use the strap 64, but the present invention is not limited to this. The moving unit 60 may use a belt such as a lap belt instead of the strap 64, or any other configuration may be used as long as the bobbin 56 of the rotating device 50 is configured to be retractable.

In the above embodiment, an air bag 70 is used as the deformable body, but the present invention is not limited to this. For example, it may be a water bag, or a bag filled with micro-sized beads, or any other shape that can be deformed.

Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and one embodiment may be appropriately combined with various modified examples, and the present invention may of course be embodied in various forms without departing from the spirit of the present invention.

10 Vehicle seat 12 Seat cushion 14 Seat back 22 Submarine prevention unit 40 Reclining mechanism 50 Rotation device 60 Moving unit 70 Air bag (deformable body)
C Reclining center R angle

Claims (1)

A seat cushion on which a passenger sits, the seat cushion having a submarine prevention portion at a front portion;
a seat back that stands upright from a rear portion of the seat cushion and serves as a backrest for a passenger seated on the seat cushion;
a reclining mechanism that rotates around a reclining center to adjust the angle of the seat back relative to the seat cushion;
a rotation device that rotates in conjunction with the reclining operation of the reclining mechanism;
a deformation body that is disposed in a rear region of the seat cushion and is forward of the rotation device and capable of deforming;
a moving section that, when the seat back is tilted backward by the reclining mechanism, moves toward the rear of the seat by being wound up by the rotating device that rotates in conjunction with the reclining operation, and deforms the deformation body toward the rear and upper part of the seat;
A vehicle seat comprising: