JP2000210161A - Seatback for vehicle seat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seatback for a vehicle seat capable of effectively absorbing a load received from a crew during the application of an impulse load. SOLUTION: A seatback 13 includes a frame 17 formed with its lower end connected to the rear end of a seat cushion 12 and its upper end extending corresponding to the rear side of the head 19b of a seated crew and a pad 16 formed of soft plastic foam so as to cover the front face of the frame 17. A hard plastic foam 21 is provided between the front face of the frame 17 corresponding to the rear side of the head 10b of the crew and the pad 16. The plastic foam is polyurethane foam.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a seat back having a lower end connected to a rear end of a seat cushion. More specifically, the present invention relates to a seat back of a vehicle seat having an upper end extending to a position corresponding to the rear of a seated occupant's head.

[0002]

2. Description of the Related Art Conventionally, a general vehicle seat has a seat cushion for receiving a rear part of an occupant, and a seat back for receiving a back part of the occupant connected to a rear end of the seat cushion through a reclining adjuster. The seat cushion is configured to wrap around the buttocks of the occupant, and the seat back is formed at a height corresponding to the shoulder of the seated occupant. The seat back is configured to wrap around the back of the occupant, and a headrest for independently receiving the back of the head of the seated occupant is provided independently above the seat back. The position of the seat cushion is adjusted in the front-rear direction by a seat track, and the inclination angle of the seat back can be adjusted by a reclining adjuster. In such a vehicle seat, the ride comfort of the occupant can be improved in a desired posture by adjusting the inclination angle of the seat back with the reclining adjuster.

[0003] On the other hand, there is known a seat such as a truck in which the upper end of the seat back is formed to extend to a position corresponding to the rear of the head of a seated occupant, thereby eliminating the need for mounting an independently formed headrest. Have been. Such a seat back includes a frame formed so as to extend to a position corresponding to the rear of the head of the occupant whose upper end is seated, and a pad made of a soft foam plastic provided to cover a front surface of the frame. A skin is integrally formed on the front surface of the pad. This seat back forms a vehicle seat by connecting the lower end of the frame to the rear end of the seat cushion, and the pad made of a soft foamed plastic absorbs a load received from a seated occupant by its elasticity to improve the riding comfort of the occupant. It is designed to improve safety. Since such a vehicle seat is mounted in the cabin of the vehicle, the width and thickness at a position corresponding to the back of the head of the occupant sitting on the seat back receive the back of the occupant in consideration of the aesthetics of the cabin. It is formed narrower and thinner than the part.

[0004]

However, the seat back formed so as to extend to the position corresponding to the rear of the head of the seated occupant cannot uniformly absorb the impact force when an impact load is applied from the rear of the vehicle. There is. That is, when an impact load is applied from the rear and the occupant is pressed against the seat back, the pad absorbs the load by elasticity, but the occupant's head is supported by the load per unit area in the portion supporting the occupant's torso. Due to the fact that the load per unit area in the part to be performed is generally higher, even if the flexible foamed plastic at the position corresponding to the rear of the occupant's torso absorbs the load received from the occupant's torso, In some cases, the soft foamed plastic at the position corresponding to the rear of the occupant's head cannot absorb all the load received from the head. Such a load that cannot be absorbed by the soft foamed plastic curves the frame constituting the seat back, and when the vehicle back panel is located near the rear of the seat back,
There is a problem that the seat back comes into contact with the back panel located on the rear side.

In order to solve this problem, it is conceivable to increase the thickness of the soft foamed plastic at a position corresponding to the back of the occupant's head. However, if the thickness of the pad is increased while the frame is left as it is, There is a problem that the amount of projection of the pad toward the front from the frame at the position corresponding to the back of the occupant's head is increased more than in other portions, thereby deteriorating the aesthetic appearance of the vehicle interior and deteriorating the occupant's riding comfort. On the other hand, increasing the thickness of the pad while devising the shape of the frame complicates the shape of the frame and raises the unit price of the seat back itself. An object of the present invention is to provide an inexpensive vehicle seat back that can effectively absorb a load received from an occupant when an impact load is applied.

[0006]

The invention according to claim 1 is
As shown in FIG. 1 and FIG.
2, a frame 17 extending to a position corresponding to the rear of the head 19b of the occupant whose upper end is connected to the rear end of the occupant.
And a pad 16 made of soft foamed plastic provided so as to cover the front surface of the frame 17. Its characteristic configuration is that the front surface of the frame 17 corresponding to the rear of the head 19b of the occupant and the pad 1
6 is provided with the hard foamed plastic 21.

According to the first aspect of the invention, the load received from the occupant sitting in the normal running state of the vehicle is protected by the elasticity of the pad 16 made of soft foamed plastic, thereby protecting the occupant. On the other hand, when an impact load is applied to the vehicle and the occupant is pressed against the seat back 13 and the occupant's head 19b contacts the seat back 13, the pad 16 first absorbs the load received from the head 19b by elasticity. And the load that the pad 16 cannot absorb completely is hard foamed plastic 2
1 absorbs. The rigid foamed plastic 21 absorbs the load without collapsing a large number of holes existing therein and generating a reaction force, and absorbs a relatively large impact load with a small amount of deformation. As a result, the hard foamed plastic 21 effectively absorbs the load that the pad 16 made of the soft foamed plastic cannot absorb, thereby protecting the occupant's head 19b. The invention according to claim 2 is the invention according to claim 1, which is a seat back of a vehicle seat in which the foamed plastic is a polyurethane foam. Polyurethane is relatively inexpensive and easy to mold. Therefore, the vehicle seat back according to the present invention can be obtained relatively inexpensively by using the polyurethane foam as the soft and hard foamed plastic.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. As shown in FIG. 3, the vehicle seat 11 includes a seat cushion 12 that receives the buttocks of the occupant and a seat back 13 that receives the back of the occupant. The seat cushion 12 and the seat back 13 are connected via a reclining adjuster 14, and the seat cushion 12
Is attached to a floor panel of a vehicle (not shown). The reclining adjuster 14 connects the rear end of the seat cushion 12 and the lower end of the seat back 13 so that the inclination angle of the seat back 13 can be adjusted. Although not shown, the seat cushion 12 is made by placing a seat cushion pad on a seat cushion frame and further enclosing the frame and pad with a cushion skin.

As shown in FIGS. 1 and 2, the seat back 13 includes a pad 16 for receiving the back of an occupant, and the pad 16
And a skin 18 covering the surface of the pad 16 and the side surface of the frame 17. The frame 17 in this embodiment is formed by welding a lower end of a headrest frame 17b formed of a steel plate to an upper portion of a frame body 17a formed by bending a metal pipe. The headrest frame 17b is formed to extend to a position corresponding to the back of the head of the seated occupant 19, and the lower end of the frame body 17a is attached to the rear end of the seat cushion 12 via a reclining adjuster 14 (FIG. 3). The pad 16 made of soft foamed plastic is composed of the frame body 17a and the headrest frame 1
It is provided so as to cover the front surface of the frame 17 made of 7b.

In this embodiment, the pad 16 is made of a soft polyurethane foam, and the pad 16 is formed into a predetermined shape by foaming inside a mold.
The skin 18 is previously laid inside the mold, and the skin 18 is integrally formed with the pad 16 by foaming soft polyurethane in this state. This skin 18
Is provided so as to cover the entire front surface of the frame 17 and the periphery of the rear surface of the frame 17. A characteristic configuration of the present invention is that a hard foamed plastic 21 is provided between the front surface of the frame 17 corresponding to the back of the head of the occupant 19 and the pad 16. As the hard foamed plastic 21 in this embodiment, a foam made of a hard polyurethane into a predetermined shape by foaming inside a mold is used. The preformed hard foamed plastic 21 is mounted inside a mold for forming the pad 16 and then foamed with polyurethane to form the pad 16.
Are formed integrally with the pad 16,
The pad 16 provided with the hard foamed plastic 21
Is attached to the frame 17 so that the rigid foamed plastic 21 is provided between the front surface of the frame 17 and the pad 16.

In the thus constructed seat back of the vehicle seat, the pad 16 made of soft foamed plastic absorbs the load received from the seated occupant in the normal running state of the vehicle by its elasticity, and protects the occupant. Improve the riding comfort. On the other hand, when an occupant is pressed against the seat back 13 by applying an impact load from the rear of the vehicle, the area of the pad 16 in the portion where the body 19a of the occupant abuts is relatively large, and the thickness of the pad 16 is also relatively large. The occupant's torso 19 when an impact load is applied
In a, the pad 16 made of a soft foamed plastic absorbs the load received from the body portion 19a by its elasticity and protects it.

In the portion supporting the occupant's head 19b, the pad 16 first absorbs the load received from the head 19b by elasticity, and the hard foamed plastic 21 absorbs the load that the pad 16 cannot completely absorb. That is, unlike the pad 16 having elasticity, the hard foamed plastic 21 absorbs the load without collapsing a large number of holes present therein and generating a reaction force. Therefore, the hard foamed plastic 21 can absorb a relatively large impact load with a small deformation amount as compared with the pad 16, and effectively absorbs the load that the pad 16 made of the soft foamed plastic cannot completely absorb. The head 19b of the occupant is protected. In addition,
In the embodiment described above, the frame body 1 made of a metal pipe is used.
7a, headrest frame 17 made of steel plate
Although the description has been made of the frame 17 to which b is attached, a headrest frame formed of a resin such as polypropylene or ABS by a mold may be used.

[0013]

As described above, according to the present invention, since the rigid foamed plastic is provided between the front surface of the frame corresponding to the rear of the occupant's head and the pad, the head cannot be completely absorbed by the pad. The rigid foamed plastic absorbs the load received from. As a result, the seat back can protect the occupant by effectively absorbing the load received from the occupant when an impact load is applied to the vehicle. In this case, the vehicle seat back according to the present invention can be obtained relatively inexpensively by using a polyurethane foam as the foamed plastic.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along line AA of FIG. 3 showing a seat back of the present invention.

FIG. 2 is an enlarged sectional view of a portion B in FIG.

FIG. 3 is a perspective view of a vehicle seat including the seat back.

[Explanation of symbols]

 12 seat cushion 13 seat back 16 pad 17 frame 19 occupant 19b head 21 rigid foam plastic

Claims (2)

[Claims] A frame (17) having a lower end connected to a rear end of a seat cushion (12) and having an upper end extending to a position corresponding to the rear of a seated passenger's head (19b); And a pad (16) made of a soft foamed plastic provided so as to cover the front surface of the occupant, the frame (17) corresponding to the rear of the occupant's head (19b).
Rigid foam plastic between the front of the pad and said pad (16)
A seat back for a vehicle seat, wherein (21) is provided. 2. The seat back of a vehicle seat according to claim 1, wherein the foamed plastic is a polyurethane foam.