JPH07108857A - Seat structure - Google Patents

Abstract

PURPOSE:To provide a seat structure which allows a seated person to easily stand up. CONSTITUTION:A quadric link mechanism and a power unit 7 are interposed between a cushion frame 3 and a seat base 2. The quadric link mechanism comprises a rear link 14 and a front link 18, the length of the rear link 14 being set greater than that of the front link 18. When a seated person leaves the seat, the telescopic rod 9 of the power unit 7 transmits torque to the rear link 14; then the rear link 14 and the front link 18 rotate and therefore the quadric link mechanism rotates, forcing the cushion frame 3 to be inclined forward while moving forward relative to the seat base 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seat structure suitable for facilitating a rising operation from a seat.

[0002]

2. Description of the Related Art For example, it is not easy for an elderly person whose leg motor function has deteriorated to stand up from a seat. As measures against such a problem, for example, Japanese Utility Model Publication No. 61-3401 has been proposed. This product connects the front end of the seat plate to the seat plate support rotatably and provides a spring between the two, so that the seat plate is normally held horizontally by the lock tool, and the lock tool is released when standing up. This is a technique in which the seat plate is flipped up by the action of a spring by operation, thereby assisting the rising motion from the seat.

[0003]

However, in the above-mentioned prior art, the pivotal movement of the seat plate is given only a simple movement about the pivot axis. Therefore, if the seat plate forms the inclined surface as it is, the center of gravity of the sitting person does not move to the front and only the waist is lifted, so that the knee is overloaded and it is difficult to stand up. In addition, when the seat is suddenly lifted, the center of gravity remains behind when the seat is suddenly lifted, so that a sitting person may slip off the seat.

An object of the present invention is to provide a seat structure in which a sitting person can easily stand up easily.

[0005]

The present invention, which has been made to solve the above-mentioned problems, has a cushion frame and a seat base located below the cushion frame, and the cushion frame and the seat base are provided. A four-bar linkage and a drive means for deforming the four-bar linkage are interposed between the four-bar linkage, and the four-bar linkage has a rear link piece formed to be longer than a front link piece, and In this case, the cushion frame and the seat base are supported substantially parallel to each other, and the cushion frame is tilted forward while being moved forward with respect to the seat base when deformed by the driving means.

[0006]

In the seat structure having the above structure, since the four-bar linkage having different link lengths is interposed between the cushion frame and the seat base located below the cushion frame, a sitting person tries to stand up. Sometimes, when the four-bar linkage is deformed by the driving means, the cushion frame tilts forward while moving forward with respect to the seat base. Therefore, the cushion frame rises so as to push forward with the deformation of the four-bar linkage. For this reason, since the movement of pushing the knees of the sitting person forward is guided, the center of gravity is brought closer to the heel side, and the waist is lifted up in that posture, which makes it easy to stand up.

[0007]

According to the present invention, since the cushion frame rises so as to approach the seat base in the forward direction, proper assistance for the rising operation is provided, and the excellent effect that the rising can be easily made is achieved. .

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a concrete embodiment of the present invention will be described with reference to FIGS.
It will be described in detail based on. FIG. 3 shows a frame structure of the seat of this example, and a pair of frame-shaped left and right seat legs 1 are fixed to a floor panel (not shown). And
A seat base 2 is placed so as to extend over the upper surface of the seat leg 1. The seat base 2 is provided with a front frame 2a and a rear frame 2b on the front and rear sides, and the front and rear frames are connected by an upper frame 2c to form a framework. A cushion frame 3 is arranged on the seat base 2. The cushion frame 3 is the lower frame 3
a and a pair of side frames 3c erected on both left and right edges of the lower frame 3a, and a pair of left and right link mounting pieces 3b is provided between the front and rear frame pieces in the lower frame 3a. . The cushion frame 3 as a whole normally has a lower frame 3a.
Are supported by being mounted in a bridging manner between the upper frames 2c of the seat base 2. A cushion 3d made of an elastic material is attached to the lower frame 3a of the cushion frame 3, and an armrest 3e made of an elastic material is attached to both side frames 3c (see FIG. 1).

A seat back frame 4 extending vertically is attached to the rear portion of the seat base 2 in the following manner. That is, the pair of left and right brackets 2d and 4a are provided on the seat base 2 side at the upper rear end thereof and on the seat back frame 4 side at the lower portion thereof, respectively. Then, as shown in FIG. 5, corresponding members are fixed by interposing bushes 5a, inserting stepped bolts 5b and tightening with nuts 5c. A seat back 4b made of an elastic material is attached to the seat back frame 4 (see FIG. 1).

A four-bar link mechanism is interposed between the cushion frame 3 and the seat base 2.
Rear link 1 arranged on the rear side of the four-bar linkage
Reference numeral 4 denotes two link pieces connected to each other at an obtuse angle, and the connecting portion is rotatably attached to the bracket 16. Further, one end of the rear link 14 is rotatably attached to a stepped bolt 20 described below which is arranged at the rear end of the link attachment piece 3b. On the other hand, the other end of the rear link 14 is rotatably connected to an end of a shaft 10 of a telescopic rod 9 described later. As for the relationship between the rear link 14 and the stepped bolt 20 described above, as shown in FIG. 4, the rear link 14 is fitted into the stepped bolt 20 via the collar 20a and is prevented from coming off by the nut 20b. It is rotatably attached to the stepped bolt 20.
The front link 18 disposed on the front side of the four-bar linkage is formed to be shorter than the rear link 14, one end side of which is rotatably attached to the front upper portion of the bracket 16 and the other end side of which is a link attachment piece. It is rotatably attached in the manner shown in FIG. 4 by a stepped bolt 20 arranged at the front of 3b.

A support stay 6a is bridged between the upper portions of the left and right seat legs 1 and at a position closer to the inner side than the rear frame 2b, and a fixing bracket 6 is fixed to the central portion thereof. A power unit 7 for tilting the entire seat is fixed to the fixed bracket 6 via a base bracket 7a attached to a base plate 7b of the unit. Base plate 7b of power unit 7
A motor 8 and a telescopic rod 9 which is linked to the motor 8 and can expand and contract by the rotation of the motor 8 are attached in parallel. An operation switch for the motor 8 of the power unit 7 is provided on the front side of the armrest 3e. A shaft 10 is attached to the tip of the telescopic rod 9 in a direction orthogonal to this and horizontally. Both ends of the shaft 10 are rotatably attached to the ends of the rear link 14 described above.

Next, the operation of the seat structure having the above structure will be described. Front link 18 and rear link 14
1 is in a state as shown in FIG. 1, so that the cushion frame 3 is supported in a substantially horizontal state with respect to the seat base 2. Also, the lower frame 3 of the cushion frame 3
a is placed on the upper frame 2c of the seat base 2,
It supports the weight of the seated person.

Next, when a seated person tries to stand up, a switch (not shown) is operated to drive the motor 8. Then, as the telescopic rod 9 contracts at a slow speed, one end side of the rear link 14 is pulled.
As a result, the rear link 14 rotates counterclockwise in FIG. 1 around the bracket 16 side, and the whole stands upright as shown in FIG. At the same time, the front link 18 also rotates counterclockwise in the drawing centering on the bracket 16 side. In addition,
When the rear link 14 stands up to a certain position, the rear link 14 contacts a limit switch (not shown), and the motor 8 is stopped based on this.

By the way, when the above-described deformation operation of the four-bar link is performed, the cushion frame 3 moves forward with respect to the seat base 2. At the same time, the length of the rear link 14, which is the rear link piece of the four-bar linkage, is set longer than the length of the front link 18, which is the front link piece. Leans forward. As described above, the cushion frame 3 performs the combined movement of the forward movement and the forward leaning with respect to the seat base 2, and as a result, the state shown in FIG. 2 is obtained. In this process, the person who is trying to stand up is guided to push forward his knees, the center of gravity is brought closer to the heel side, and the waist is lifted higher, so that the person can stand up comfortably. If the switch (not shown) of the power unit 7 is operated from the state shown in FIG. 2 to rotate the motor 8 in the reverse direction, the four-section link is restored and deformed, and if the return of the cushion frame 3 is detected by the limit switch (not shown), the motor is restored. 8 stops and returns to the state shown in FIG.

As described above, according to the present example, when a seated person tries to stand up, the user is guided to move the knee forward and the waist is lifted high while moving the center of gravity to the front side. , It is easy to stand up smoothly without putting an excessive load on the knees. This has a remarkable effect as a seat structure especially for elderly people. Further, since the cushion frame 3 is lifted by the driving force of the power unit 7, it is possible to realize a stable start-up assistance regardless of the weight of the seated person. Furthermore, in this example, since the cushion 3d with the armrest 3e is lifted, the armrest 3e
Compared with the type in which only the seat plate is simply lifted without the use of the cushion, the body can be supported at the time of standing up, and a stable feeling can be obtained at the time of standing up without sliding down from the cushion 3d. Further, since a person who is about to sit down can sit while moving the center of gravity to the rear side in response to the guidance of the motion of stretching the knee, the burden of sitting while bending the knee and supporting the weight is reduced.

Although the power unit 7 is applied as the driving means in this example, for example, a torsion spring or a coil spring is used as the driving means.
It can also be configured to transmit an acting force that deforms the joint link mechanism. In this case, for example, a lock mechanism that locks the biasing force of the spring is provided, and the lock mechanism is released at the time of rising to transmit the biasing force of the spring to either the rear link 14, the front link 18, or the cushion frame 3. It may be configured as follows. Further, in this example, the rear link 14 is composed of two link pieces, but it is also possible to form both as an integral link piece. Further, for example, a hydraulic cylinder is provided at the position of the rear link piece of the four-bar linkage, and the hydraulic cylinder is expanded and contracted to move the cushion frame 3 forward with respect to the seat base 2. Can be tilted.

[Brief description of drawings]

FIG. 1 is a side view of a seat in a seated state.

FIG. 2 is a side view of the seat in a standing state.

FIG. 3 is an exploded perspective view of a seat

FIG. 4 is a vertical cross-sectional view showing a mounting portion of a link mechanism.

FIG. 5 is a vertical sectional view showing a mounting portion between a seat back frame and a seat base.

[Explanation of symbols]

 1 ... Seat leg 2 ... Seat base 3 ... Cushion frame 7 ... Power unit 14 ... Rear link 18 ... Front link

Claims (1)

[Claims] 1. A cushion frame, and a seat base located below the cushion frame, wherein a four-bar linkage mechanism is provided between the cushion frame and the seat base, and the four-bar linkage mechanism is deformed. With the drive means interposed, the four-bar linkage has a rear link piece formed to be longer than a front link piece, and normally supports the cushion frame and the seat base substantially parallel to each other, A seat structure, wherein the cushion frame is tilted forward while being moved forward with respect to the seat base when deformed by the drive means.