JPH09123819A - Suspension device of vehicular seat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obviate operation by an operation member, and improve comfortableness to sit on even in an occupant whose body weight is light and an occupant whose body weight is heavy by arranging a coil spring to always energize upper frames upward and a coil spring actuated when this coil spring elongates by a prescribed vertical directional load. SOLUTION: Lower frames 9 and 9' are arranged on the car floor side, and seat side upper frames 8 and 8' are movably connected in the vertical direction through links 3, 3' and 4, 4' to its lower frames 9 and 9', and a damper 6 and coil springs 1 and 2 are arranged on the lower frame 9, 9' side and the upper frame 8, 8' side. This coil spring 2 always energizes the upper frames 8 and 8' upward, and when the coil spring 2 elongates by a prescribed vertical directional load, the coil spring 1 is actuated. Therefore, operation by an operation member is obviated, and comfortableness to sit on can be improved even in an occupant whose body weight is light and an occupant whose body weight is heavy.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension device used for a vehicle seat such as a truck.

[0002]

2. Description of the Related Art Some suspension devices used in the driver's seat of a truck or the like have a load-deflection characteristic in which the deflection changes with a non-linear value as the load increases.
It is known that a seat having this characteristic is comfortable to sit for a light-weight occupant and a heavy occupant.

By the way, in this suspension device, as disclosed in, for example, Japanese Patent Application Laid-Open No. 53-116629, the operating member can change the tension between the two tension coil springs and simultaneously change the distance between the operating points of the tension coil springs. The initial load and the spring constant are both changed by the operation of.

[0004]

Therefore, in the conventional product of the previous term, the tension of the tension coil spring must be changed by operating the operating member by a light-weight occupant or a heavy occupant, which is a troublesome operation. there were.

Therefore, an object of the present invention is to provide a suspension device which does not require any operation by an operating member and has a comfortable sitting comfort for both light and heavy occupants.

[0006]

In order to achieve the above object, a vehicle seat suspension device according to the present invention includes a vehicle-floor-side lower frame and a seat-side upper frame in a vertical direction via a link. In a suspension device for a vehicle seat in which a damper and a coil spring are disposed on the lower frame side and the upper frame side, the coil spring is a coil spring B that constantly urges the upper frame upward. The coil spring B is composed of a coil spring A that operates when it is expanded by a predetermined vertical load.

Therefore, when an occupant with a light weight sits, the elastic force of only the coil spring A acts, and when an occupant with a heavy weight sits, the elastic force of the coil spring B acts in addition to the coil spring A.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a suspension device according to the present invention. In the figure, (9) and (9 ') are a pair of left and right lower frames fixed to the vehicle floor side in the front-rear direction of the vehicle. (8) and (8 ') are a pair of left and right upper frames fixed to the bottom of the seat. The upper frames (8) and (8') are connected to the lower frames (9) and (9 ') by a pair of front and rear links (3). ) (3 ') (4) (4') are movably connected in the vertical direction.

The pair of front and rear links is the front link (3)
(3 ') and rear links (4) and (4'), and the pair of left and right front links (3) and (3 ') and the pair of left and right rear links (4) and (4') are respectively left and right lower frames. (9)
The links (3) ... Are each substantially triangular in shape and are rotatably supported by the support shafts (32) and (42) that are laterally mounted on (9 ′), and the support shafts (32) and (42) are approximately at the centers thereof. Each of the links (3) ... Is inserted, and rotates about the support shafts (32) (42).

Front link (3) (3 ') and rear link (4)
(4 ') is connected by a connecting rod (7) (7'),
In the figure, (33), (33 '), (46) and (46') indicate pivot pins in which the ends of the connecting rods (7) (7 ') are rotatably attached to the links (3).

Upper frames (8) (8 ') are connected to the connecting pins (35) (3) at the ends of the links (3).
5 ') (45) (45') are pivotally mounted. Then, the mounting shafts (41) (41 ') are mounted on the other ends of the rear links (4) (4'), and the mounting shaft (41) of one rear link (4) is mounted on the rear link (4). It is attached so as to project inward and outward respectively, and a buffer body (5) is provided at a portion projecting inward thereof, and a rotary cylinder (43) is provided at a portion projecting outward.

The pivot pin (33) provided on one of the front links (3) is formed so as to project inward and outward of the front link (3). , A bush (34) made of a flexible sound deadening material,
Rotating cylinders are attached to the parts protruding outward, respectively.

A damper (6) is provided between the rotary cylinder of the pivot pin (33) and the rotary cylinder (43) of the mounting shaft (41).
Is installed, and shocks due to sudden vibration of the vehicle body are buffered by this damper (6).

Further, the pivot pin (3) of the front link (3 ')
3 ') and a mounting shaft (41') of the rear link (4 ') are provided with a coil spring B (2) consisting of a tension coil spring.
The elastic force of the coil spring B (2) constantly urges the upper frame (8 ') upward through the rear link (4) and the front link (3').

On the other hand, the pivot pin (33) of the front link (3)
One end (12) of a coil spring A (1), which is a tension coil spring, is hooked on the bush (34) provided at the other end, and the other end (11) of the coil spring A (1) is a hook bent in a U shape. Thus, the shock absorber (5) provided on the mounting shaft (41) of the rear link (4) is slidably engaged in the longitudinal direction.

The cushioning body (5) is made of a flexible material such as rubber or soft synthetic resin, and as shown in FIG.
Are provided in the circumferential direction, and the other end (11) of the coil spring A (1) is engaged with the groove (50).

The above coil spring A (1) is a coil spring B.
In contrast to (2), a tension coil spring having a small spring constant is used by reducing the wire diameter, increasing the coil diameter, or increasing the number of turns, and the coil spring B (2) has a constant length. The other end (11), which is a long hook, is attached to the shock absorber (5) so that it is activated only when the load is extended.

That is, the mass of the occupant and the seat is about 85 kg.
In the case of −90 kg or less, only the coil spring B (2) operates, but the coil spring A (1) does not operate as shown in FIG. In addition to the coil spring B (2), as shown in FIG.
(1) is configured to operate.

When the coil spring A (1) is activated,
The other end (1) of the coil spring A (1) is caught by the shock absorber (5), and a shock is generated. This shock is generated by the shock absorber (5).
Since it is absorbed by the elasticity of, there is no risk of causing discomfort.

[0020]

According to the present invention, a coil spring B that constantly urges the upper frame upward and a coil spring A that operates when the coil spring B is extended to a certain length by a load are used. A nonlinear characteristic is obtained in which the deflection changes with a nonlinear value as the load increases.
Therefore, unlike the conventional product, it is not necessary to operate the operating member to change the spring constant of the coil spring according to the occupant having a light weight and the occupant having a heavy weight, and the nonlinear characteristic of the suspension can be obtained. Therefore, when the vertical stroke of the upper frame is small, the stroke becomes soft, and when the stroke of the upper frame is large, the stroke becomes hard and bottoming can be prevented.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view of a device of the present invention.

FIG. 2 is a perspective view of a cushioning body used in the device of the present invention.

FIG. 3 is a side view showing a state before the coil spring A operates in the device of the present invention.

FIG. 4 is a side view showing the operating state of the coil spring A from the state of FIG.

[Explanation of symbols]

 1 coil spring A 2 coil spring B 3 link 3'link 4 link 4'link 5 shock absorber 6 damper 8 upper frame 8'upper frame 9 lower frame 9'lower frame

Claims (3)

[Claims] 1. A seat side upper frame is movably connected to a lower frame provided on a vehicle floor side through a link through a link, and a damper and a coil spring are provided on the lower frame side and the upper frame side. In the vehicle seat suspension device, the coil spring includes a coil spring B that constantly urges the upper frame upward, and a coil spring A that operates when the coil spring B is extended by a predetermined vertical load. Seat suspension system. 2. The suspension device for a vehicle seat according to claim 1, wherein an end portion of the coil spring A is hooked on a cushioning body. 3. The coil spring A with respect to the coil spring B
The suspension device for a vehicle seat according to claim 1, wherein the spring constant is small.