JP2002046515A - Vehicle seat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle seat provided with a means to further smoothly move a seat back to a rear against rapid rear movement operation of a seating person due to inertia occurring due to a shock force from a rear toward a front during a rear-end collision and to provide the shock absorbing unit of a shock absorbing means to continuously absorb the shock force by an approximately constant absorption force. SOLUTION: The vehicle seat described above comprises a bracket on the moving side being on the seat back side; a bracket on the fixed side provided with a seat cushion; a rearward movement means of the seat back formed in a quartric mechanism-form state similar to a parallel link or the link piece consisting of a pair of link pieces pivotally supported at the two brackets; and a shock absorbing means to absorb shock energy occasioned by movement of the seat back. The shock absorbing unit comprises a cylinder body provided at a base end with a mounting part; a moving element previously pressed in a position closer to a base end in the cylinder body; and a rod for towing the moving element having one end fixed at the moving element and the other end having a mounting part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle seat, and more particularly to a vehicle seat for reducing the impact of a occupant upon a rear-end collision.

[0002]

2. Description of the Related Art As a prior art of a vehicle seat for reducing the impact received by a seated occupant in a rear-end collision, Japanese Patent Application Laid-Open No. 9-2 is disclosed.
No. 72,368. This vehicle seat has a support portion on the seat back side, a bracket on the seat cushion side, and a seat cushion frame, which are pivotally mounted at respective end portions, and a side wall portion of the seat cushion frame extends in the front-rear direction. A long hole is provided, and a pin implanted at each of the front and rear ends of the bracket is inserted into the long hole, thereby moving the seat back in the front-rear direction along the long hole of the seat cushion frame. Means, between the bracket and the side wall portion of the seat cushion frame are a tapered inner cylinder and an outer cylinder whose diameter gradually decreases toward the rear, and the short end of the inner cylinder is located at the front end of the bracket. The long diameter end of the outer cylinder is attached to the side wall, so that it can be attached by inertia caused by an impact force from the rear to the front when the vehicle is collided. In the sudden backward movement of the user, the outer cylinder is expanded with the rear movement of the inner cylinder with respect to the outer cylinder, and the impact force is absorbed by reducing the diameter of the inner cylinder. In addition to achieving the absorbing function efficiently, the long holes forming the parallel moving means are formed in the side wall of the seat cushion frame, so that the impact force can be obtained regardless of the angle of inclination of the seat back support and the bracket, that is, the seat back. The seat back can be reliably moved in a direction along the direction in which the seat back acts.

[0003]

Since the vehicle seat is equipped with a reclining unit for tilting and adjusting the seat back, the seat is often operated with the seat back slightly tilted backward, and therefore, a rear-end collision occurs. The inertial force to the occupant due to the impact force at the time of the impact may act as a rotational force (moment) downward and rearward. According to this, the vehicle seat according to the conventional technique is inserted into the long hole in the front-rear direction (horizontal direction) provided in the side wall of the seat cushion frame by the seat back moving means. It is characterized by using a means for moving the pins of the bracket rearward, thereby moving the seat back in the direction along the direction in which the impact force acts, so that the direction in which the inertial force acts and the seat back The movement direction of the seat back is different, and the resistance to the movement of the pin in the long hole is increased. Therefore, it cannot be said that the seat back moves smoothly, and as a result, the shock absorbing means does not function sufficiently. In addition, since the means for absorbing the impact force is based on the expansion of the outer cylinder and the reduced diameter deformation of the inner cylinder in the tapered inner cylinder and the outer cylinder, the impact at the initial stage when the inner cylinder moves in the outer cylinder is reduced. It cannot be said that it is sufficiently absorbed, and it is considered to be disadvantageous for absorbing the impact force. That is, the reduction of the instantaneous impact force applied to the occupant (seat occupant) is achieved by the constant impact absorption force acting continuously.

In view of the above problems, an object of the present invention is to prevent a occupant from suddenly moving backward due to inertia caused by an impact force from the rear to the front when a collision occurs.
Means for moving the seat back backward more smoothly, and a vehicle seat provided with shock absorbing means for absorbing an impact force, and
An object of the present invention is to provide an impact absorbing unit that continuously absorbs an impact force with a substantially constant absorption force.

[0005]

A vehicle seat as a first means for achieving the above object has a movable side bracket on a seat back side, a fixed side bracket provided with a seat cushion, A pair of link pieces rotatably supported by the two brackets are used as a parallel link or a four-bar mechanism similar to the parallel link. The shock absorbing unit for a vehicle seat, which is a second means, has a cylindrical body having a mounting portion at a base end, and is press-fitted in advance near a base end in the cylindrical body. And a rod for retracting the movable element having one end fixed to the movable element and an attachment portion at the other end.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment of a vehicle seat according to the present invention.
An embodiment will be described with reference to FIGS. The vehicle seat in this embodiment includes a seat cushion 1 serving as a seat and a seat back 2 serving as a backrest. The seat cushion 1 is attached to an upper rail bracket 4 that is slidably fitted to a lower rail 3. Has a seat back bracket 5 (hereinafter referred to as an upper bracket) fixed thereto, and the upper bracket 5 can be rotated by a seat bracket 6 (hereinafter referred to as a lower bracket) and a reclining unit 7 (not described in detail). It is attached to. Further, between the lower bracket 6 and the upper rail bracket 4, a rearward moving means A of the seat back 2 is provided.
And the shock absorbing means B, whereby the tilt angle of the seat back 2 can be adjusted by the reclining unit 7 and the vehicle seat moves along the lower rail 3 in the front-rear direction of the vehicle. It can be adjusted.

The rear moving means A of the seat back 2 is
Connect one end to the upper rail bracket 4 that is the fixed side,
A pair of longitudinal link pieces each of which is rotatably supported at the other end thereof on a lower bracket 6 which is a movable side is arranged in parallel. The rear link pieces 9 in the rear direction are equal in length and parallel to each other, that is, the upper rail brackets 4 of both link pieces 8 and 9.
A parallel-joint mechanism (parallel link, parallel crank) having a parallelogram in which the distance between the pivot portions 8a and 9a on the side of the lower bracket 6 and the distance between the pivot portions 8b and 9b on the side of the lower bracket 6 is equal is provided. It is positioned obliquely so as to be located above and to have the movable-side pivot portions 8b, 9b, which are normally the lower bracket 6 side, located behind the fixed-side pivot portions 8a, 9a, which are the upper rail bracket 4 side. Is what it is.

As a result, the seat back 2 maintains the posture before the movement by the front link piece 8 and the rear link piece 9 swinging rearward about the fixed side pivots 8a, 9a on the upper rail bracket 4 side as a fulcrum. While moving (parallel posture), the vehicle moves downward on the circular arc locus whose radius is the length of both link pieces 8 and 9.

In the shock absorbing means B, a shock absorbing unit 10 is disposed between the front link piece 8 in the rearward moving means A of the seat back 2 and the upper rail bracket 4. The shock absorbing unit 10 includes a cylindrical body 11, a hemisphere 12 pre-pressed near a base end in the cylindrical body 11, and a rod 13 for pulling the hemisphere 12, and the hemisphere 12 has a front side. A threaded portion 13a provided at one end of the rod 13 is penetrated from the spherical surface side, and is fixedly fastened with a nut 13b on the rear plane side. This is shown in FIG. In the graph of the pulling load before pulling out to the opposite side, the phenomenon of a constant load part in the diagram from the large load at the time of insertion from the inlet to the almost constant continuous small load from the insertion until the pulling out is adopted It was done.
The mounting portion at the distal end of the rod 13 in the shock absorbing unit 10 is pivotally supported at a substantially central portion of the front link piece 8 so as to be pivotable, and the mounting portion at the base end of the cylindrical body 11 is turned to the upper rail bracket 4. The shock absorbing means B is constituted by movably supporting.

Thus, in a sudden rearward movement of the occupant due to inertia caused by an impact force from the rear to the front when a rear-end collision occurs, the seatback 2 is moved rearward by the rearward transition means A of the seatback. With the swing of the front link 8 when moving, the rod 13 of the shock absorbing unit 10 pivotally supported by the front link 8 is pulled, and the hemisphere 12 pressed into the cylinder 11 is turned into the cylinder 11. While increasing the diameter, the continuous substantially constant resistance force caused by the movement toward the open end of the cylindrical body 11 is used as the absorption energy of the impact energy, thereby absorbing the impact.

The front link 8 and the pivotal support 13c of the rod 13 in the shock absorbing means B have a direction in which the arc line of motion of the front link 8 and the direction of extension of the rod 13 at the time of shock absorption are substantially similar, that is, the shock absorbing action. The hemisphere 12 in the shock absorbing unit 10 has a spherical surface to cope with a lateral displacement of the shock absorbing action direction, and is not necessarily limited to this shape. However, it is sufficient if the moving element is press-fitted into the cylindrical body 11 in advance. Further, since the impact absorbing means B has a relationship between the seat back 2 on the movable side and the upper rail bracket 4 on the fixed side, the impact absorbing unit 1
0 may be disposed between the lower bracket 6 and the upper rail bracket 4.

Therefore, in the vehicle seat according to this embodiment, the rearward moving means A of the seat back 2 includes a movable side of the seat back 2, a fixed side of the upper rail bracket 4, and a pair of link pieces 8, 9, a parallel link mechanism having a parallelogram shape is provided, and the movable link single pivots 8b, 9b are disposed rearward of the vehicle with respect to the fixed link single pivots 8a, 9a. Therefore, in addition to the case where the inertial action from the front to the rear of the vehicle acts horizontally on the seat back 2 and the case where the inertial action acts on the seat back 2 with the rearward downward rotational moment in a state where the seat back 2 is tilted backward, Since the seat back moves downward in the rear of the vehicle with the swing of the link pieces, the seat back can cope with the inclination angle of the seat back. Direction of movement of the click, since it is made and the corresponding with the arc movement against linear inertia acting direction, the movement can be smoothly performed.

Further, the shock absorbing unit 10 in the shock absorbing means B employs a means in which a hemisphere 12 previously press-fitted into the cylinder 11 moves while expanding the diameter of the cylinder 11 during an impact load. Absorbing force is absorbed by continuing the resistance (absorbing power) of the shock absorber. Since absorption is constant, it is possible to set an ideal setting for shock. Can be set to a minimum. Incidentally, since the shock absorbing means in the above-mentioned prior art (Japanese Patent Application Laid-Open No. 9-272368) is based on the relative movement of the tapered inner and outer cylinders, the resistance (absorbing power) gradually increases, and the absorbing power is increased. Is not stable, so that it is difficult to set the standard. The rear moving means A and the shock absorbing means B of the seat back are relatively arranged also on the opposite side of the seat. For example, the axis of the pivot 8a of the front link piece 8 in the rear moving means A is extended. If it is fixed to the front link piece 8 on the opposite side to form a pivot 8a, the left and right sides of the seat are reliably operated (rotated) in conjunction with each other, so that the seat back 2 is retracted without twisting left and right. It moves, and it becomes possible to perform ideal shock absorption together with the operation of the shock absorbing means B.

FIGS. 5 and 6 show another embodiment of the means for moving the seat back rearward in the vehicle seat. Members having the same functions as those of the first embodiment are denoted by the same reference numerals, and duplicate description will be omitted.

FIG. 5 shows a second embodiment of the present invention. In the vehicle seat, the rearward moving means A 'of the seat back 2 moves the lower part of the seat back 2 rearward from the upper part when the seat back 2 moves rearward. In the first embodiment, the front link piece 8 and the rear link piece 9 of the parallelogram shape provided between the upper rail bracket 4 and the lower bracket 6 are provided.
This is a four-joint mechanism in which the pivot portion 8a of the front link piece 8 on the upper rail bracket 4 side is located above the pivot portion 9a of the rear link piece 9 and the length of the front link piece 8 is shorter than the rear link piece 9. is there.

FIG. 6 shows a third embodiment. In this vehicle seat, the backward moving means A '' of the seat back 2 is used to move the seat back 2 backward in the same manner as in the second embodiment. The parallelogram-shaped front link piece according to the first embodiment, which is provided between the upper rail bracket 4 and the lower bracket 6, characterized in that the lower part is moved more rearward than the upper part. 8 and the rear link piece 9, the pivot portion 8 a of the front link piece 8 on the side of the upper rail bracket 4 is displaced in the vehicle forward direction, that is, only the distance between the pivot point 9 a of the rear link piece 9 is increased. The length of the front link piece 8 is increased, and only the front link piece 8 is inclined to form a four-bar mechanism.

In the second and third embodiments, when the seat back 2 is moved rearward, when the front link piece 8 and the rear link piece 9 are pivoted rearward about pivot points 8a, 9a which are fixed sides, the pivot points 8a, 9a are used as fulcrums. Since the swing angle of the front link piece 8 is wider than that of the rear link piece 9, the pivot angle between the movable-side pivot portions 8b and 9b (line 8
b, 9b) are not parallel and move while inclining in front of the vehicle, so that the seat back 2 retreats more in the lower part than in the upper part.

The vehicle seat shown in FIG. 7 has, in addition to the seat back rearward moving means A and the shock absorbing means B in the first embodiment, a seat cushion rearward moving means accompanying the rearward movement of the seat back. 14 shows a fourth embodiment. Members having the same functions as those of the first embodiment are denoted by the same reference numerals, and duplicate description will be omitted.

The vehicle seat swings about the axis of the pivot 8a of the front link 8 pivotally supported by the upper rail bracket 4 in the rearward moving means A of the seat back 2 shown in the first embodiment. A piece 14a is fixed, and a swinging piece 14b is pivotally supported at the front end portion of the upper rail bracket 4 in the vehicle front direction.
a, 14b, the mounting pieces 15a, 15
b is rotatably supported, and the seat cushion 1 is fixed to the mounting pieces 15a, 15b. The two rocking pieces 14a, 14b have the same length, and the rocking pieces in the upper rail bracket 4 are provided. The distance (line segments 8a, 4a) between the pivoting portion 8a of the pivoting piece 14a and the pivoting portion 4a of the pivoting piece 14b (the line segments 8a, 4a) and the pivoting tip portions pivoting portions 15c, 1 of the both pivoting pieces 14a, 14b.
The upper rail bracket 4 has a parallel link shape in which the distances between the 5d (line segments 15c, 15d) are the same.
The pivot portions 15c and 15d, which are closer to the seat cushion 1 (movable side) than the pivot portions 4a and 8a on the side (fixed side), are disposed in the rear direction of the vehicle.

Accordingly, the seat cushion 1 is pivoted on the pivot of the pivot 8a, which is the pivot of the front link 8 as the front link 8 pivots in the backward movement of the seat back 2 by the backward moving means A. The fixed rocking piece 14a and the rocking piece 14b pivotally supported at the distal end portion of the upper rail bracket 4 rock rearward together with the front link piece 8 (rear link piece 9), so that both rocking pieces are formed. Via mounting pieces 15a and 15b pivotally supported at the swinging tip portions of 14a and 14b,
The seatback 2 moves rearward and downward with the rearward downward movement.

Accordingly, in the vehicle seat according to this embodiment, not only the seat back 2 but also the seat cushion 1 move rearward due to the rearward movement of the occupant due to the impact force to the front of the vehicle when the rear-end collision occurs. In addition, the shock absorbing means B absorbs the shock of the sudden backward movement, so that the occupant can be effectively protected from the shock.

[0022]

The vehicle seat according to the present invention comprises a parallel link or a parallel link comprising a bracket on the seat back side, a bracket on the seat cushion side, and a pair of link pieces pivotally supported by the two brackets. Since it is provided with a rearward moving means for the seatback configured in a four-bar mechanism similar to the above, and a shock absorbing means for absorbing the shock energy with the movement of the seatback, from the rear to the front when the rear-end collision occurs In addition to the case where the sudden rearward movement of the occupant due to inertia caused by the impact force directed toward the seat acts horizontally on the seat back, and the case where the seat back acts with the rearward downward rotating moment when the seat back is inclined backward. Even if the seat back moves, the seat back moves downward with the link pieces swinging, so it can respond to the seat back inclination angle. At the same time, the direction of movement of the seat back also corresponds to the direction of the linear inertia action by circular movement, so that the movement is performed smoothly, and therefore, the impact accompanying the movement of the seat back is The absorbing means also works smoothly.

Further, the shock absorbing unit has a cylindrical body having a mounting portion at a base end, a movable element press-fitted in advance near the base end in the cylindrical body, and one end fixed to the movable element,
At the other end, the moving member in the cylinder is expanded by the moving member in the cylinder due to the detaching action of the mounting portion of the cylinder and the mounting portion of the rod, since the moving member is constituted by the rod for retracting the moving member having the mounting portion at the other end. As it moves in the direction of the open end while absorbing, it absorbs impact energy with continuous substantially constant absorption power, so if it is adopted as the impact absorbing means of the vehicle seat, the impact of the occupant is effectively reduced. can do.

[Brief description of the drawings]

FIG. 1 is a side view of a vehicle seat.

FIG. 2 is a partially enlarged side view showing a moving state of a seat back.

FIG. 3 is a partially enlarged view of a shock absorbing unit (shock absorbing unit).

FIG. 4 is a graph of a pull-out load of the shock absorbing unit.

FIG. 5 is a side view of a vehicle seat according to a second embodiment.

FIG. 6 is a side view of a vehicle seat according to a third embodiment.

FIG. 7 is a side view of a vehicle seat according to a fourth embodiment.

[Explanation of symbols]

 A, A ', A' 'Backward moving means of seat back B Shock absorbing means 1 Seat cushion 2 Seat back 3 Lower rail 4 Upper rail bracket 4a Pivot 5 Seat back bracket (upper bracket) 6 Seat bracket (lower bracket) 7 Reclining unit 8 Front link piece 8a, 8b Pivot part 9 Rear link piece 9a, 9b Pivot part 10 Shock absorbing unit 11 Cylindrical body 12 Hemisphere 13 Rod 13a Screw part 13b Nut 13c Pivot part 14a, 14b Oscillating piece 15a, 15b Mounting Piece 15c, 15d pivot

Claims (2)

[Claims] When a vehicle receives an impact from the rear to the front, the vehicle seat for reducing the impact includes a movable bracket serving as a seat back, and a fixed bracket provided with a seat cushion. A bracket and a pair of link pieces rotatably supported by the two brackets are formed into a parallel link or a four-bar mechanism similar to the parallel link, and swing about a pivot on a fixed side of the link piece. A vehicle seat comprising: a seatback rearward moving means for moving a seatback along an arc locus downward of a vehicle rearward; and an impact absorbing means for absorbing impact energy as the seatback moves. 2. A cylindrical body having a mounting portion at a base end, a movable element press-fitted near a base end in the cylindrical body,
One end is fixed to the mover, and the other end is composed of a rod for retracting the mover having an attachment portion. With the attachment portion of the cylinder and the separating action of the attachment portion of the rod, the mover in the cylinder is A shock absorbing unit for a vehicle seat, wherein a shock absorbing unit absorbs shock energy with continuous substantially constant absorbing power by moving the cylindrical body in the direction of the open end while expanding the diameter.