JP2003009986A - Lifting device for seat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lifting device for a seat which is advantageous in flexibility to utilize a space and gives a user an improved feeling when operating. SOLUTION: An inner end 27a of an assisting, spiral spring 27 is caught on a second rotary shaft 25 eccentric from a first rotary shaft 21 of a sector gear 22. When a seat is lowering, a spring force F of the spiral spring 27 becomes larger gradually. A distance H between the centers of the second rotary shaft 25 and of a pin 8d becomes longer gradually. The spring force applied to the pin 8d becomes approximately constant. When the seat is lifting, a spring force f of the spiral spring 27 becomes smaller gradually. A distance h between the centers becomes shorter gradually. The spring force applied to the pin 8d becomes approximately constant. As a result, a force for operating the sector gear 22 becomes approximately constant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seat lifting device.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS.
For example, in some seats 1 for vehicles, a lift mechanism 3 for raising and lowering the seat cushion 2 is arranged between the floor, an upper rail of a slide device, etc. and the seat cushion 2 (for example, the actual opening 59). -104
832).

This lift mechanism 3 has an I provided on the front side.
One end of the shaped link 5 has a pin 6 on the front portion of the base frame 4.
a, the other end is connected to the cushion frame 2'by a pin 6b, the middle part of the L-shaped link 7 provided on the rear side is connected to the base frame 4 by a pin 8a, and one end is a cushion. It is connected to the frame 2'by a pin 8b, and the other end is connected to the rear end of the connect rod 9 by a pin 8c.

Further, a sector gear 11 which is rotated by a pinion 10a linked to the manual operation dial 10 is provided at the front portion of the base frame 4, and the sector gear 11 is provided.
The front end portion of the connector rod 9 is connected with a pin 8d.

When the manual operation dial 10 is operated to rotate the sector gear 11 via the pinion 10a,
The L-shaped link 7 is rotated to the right through the connect rod 9 and the cushion frame 2 ′, that is, the rear side of the seat cushion 2 is raised (see the chain double-dashed line).

The inner end portion of the assisting spiral spring 13 is locked to the rotary shaft 12 of the sector gear 11, and the outer end portion thereof is locked to the spring hooking pin 14 of the sector gear 11, and this spiral spring 13 is locked. The spring force assists the rearward rise of the seat cushion 2.

Although not specifically shown, a brake drum or the like is provided to prevent the manual operation dial 10 side from being reversely rotated by the load acting on the seat cushion 2 side.

[0008]

However, since the inner end of the spiral spring 13 is locked to the rotary shaft 12 of the sector gear 11, it is often disadvantageous in terms of space and, for example, the seat cushion 2 is raised to the maximum. When descending from the position to the lowest position, the spring force gradually increases as the winding of the spiral spring 13 increases.
As shown in, there is a problem that the operation force of the sector gear 11 is gradually increased and the operation feeling is bad.

The present invention has been made to solve the above-mentioned conventional problems, and is advantageous in terms of space, and
An object of the present invention is to provide a seat lift device that improves the operation feeling.

[0010]

In order to solve the above-mentioned problems, the present invention is provided with a sector gear which is rotated by an operation, and a lift for raising and lowering a seat via a link member linked to the rotation of the sector gear. In the apparatus, a cam plate rotated by a second rotary shaft that is eccentric from the first rotary shaft of the sector gear, an inner end of the cam plate that is locked by the second rotary shaft, and an outer end of the cam plate by the second rotary shaft. An engaging spiral spring for assisting is provided, and an elongated hole into which a pin provided on the sector gear fits is formed in the cam plate. The elongated hole has a spring force F of the spiral spring.
The center-to-center distance H between the second rotary shaft and the pin at the lowest descent position of the seat is the maximum between the center of the second rotary shaft and the pin at the highest position of the seat where the spring force f of the spiral spring is minimum. The present invention provides a seat lifting device, characterized in that the pin is formed so as to be longer than the distance h.

According to the present invention, the inner end portion of the assisting spiral spring is locked to the second rotary shaft eccentric from the first rotary shaft of the sector gear, and the spring force F of the spiral spring gradually increases. In the descending direction of the sheet, the center-to-center distance H gradually increases and the spring force acting on the pin becomes substantially constant, and the spring force f of the spiral spring gradually decreases. Since h is gradually shortened and the spring force acting on the pin becomes substantially constant, the operation force of the sector gear becomes substantially constant.

As described in claim 2, the product of the spring force F and the center-to-center distance h and the product of the spring force f and the center-to-center distance H have a substantially constant relationship, and the spring force acting on the pin is maximized. It is preferable that it is substantially constant between the position and the lowermost position.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that parts having the same configurations and functions as those of the conventional technique are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIGS. 1 and 2, the sector gear 22 rotatably supported by the first rotating shaft 21 on the front portion of the base frame 4 has a hole 9a at the front end portion of the connect rod 9. Push nut 28 fitted to pin 8d
It is fastened at b.

A spring set plate 23 is provided so as to straddle above the sector gear 22, one end 23a of the spring set plate 23 is fixed to the base frame 4 by caulking pins 24, and the other end 23b has a hole 23c.
Are fitted into and supported by the first rotary shaft 21.

The spring set plate 23 has the structure shown in FIG.
In the side view of (a), the first rotary shaft 21 of the sector gear 22 is shown.
The second rotating shaft 25, which is eccentric to the front and diagonally upward, is fixed,
The center hole 26a of the cam plate 26 in the second rotary shaft 25
Is rotatably supported.

The assisting spiral spring 27 has an inner end portion 27.
The a is fitted and locked in the slot portion 25a of the second rotary shaft 25, and the outer end portion 27b is locked in the spring hook portion 26b of the cam plate 26. After the inner end portion 27a of the spiral spring 27 is fitted into the slit portion 25a of the second rotary shaft 25, the push plate nut 28a is fixed to the tip of the second rotary shaft 25, whereby the cam plate 26 and the spiral spring 25 are fixed. The inner end portion 27a of 27 is prevented from coming off.

The cam plate 26 is formed with an elongated hole 26c into which the pin 8d provided on the sector gear 22 is fitted.

As shown in FIG. 1A, the elongated hole 26c is
The center-to-center distance H between the center of the second rotating shaft 25 (center of the spiral spring 27) and the center of the pin 8d at the lowest position of the seat cushion 2 where the spring force F of the spiral spring 27 is maximum is:
As shown in FIG. 1 (b), it is longer than the center-to-center distance h between the center of the second rotating shaft 25 and the center of the pin 8d at the highest position of the seat cushion 2 where the spring force f of the spiral spring 27 is minimum. The pin 8d is formed so as to move.

Here, the spring force F is the spring force applied to the spring hook portion 26b of the cam plate 26 at the lowest position,
The spring force f is the spring force applied to the spring hooking portion 26b of the cam plate 26 at the highest position. In addition, the distance (always constant) between the center of the second rotating shaft 25 and the outer end portion 27b locked to the spring hooking portion 26b of the cam plate 26 is W
And

In the prior art, F × W / H> f × W / H ... (F> f), which increases the operating force at the lowest position (see FIG. 4). In the form, F × W / H≈f × W / h ... (F> f H> h), and the operating force at the highest position and the lowest position is almost constant (see FIG. 5). That is, the product of the spring force F and the center-to-center distance h and the product of the spring force f and the center-to-center distance H are set to a substantially constant relationship (F × h≈f × H), and the spring force acting on the pin is maximized. It is designed to be substantially constant between the ascending position and the most descending position.

With the lift device as described above, FIG.
At the lowermost position of the seat cushion 2 shown in (a),
The spring force F of the spiral spring 27 is maximized, but the center-to-center distance H between the center of the second rotary shaft 25 (center of the spiral spring 27) and the center of the pin 8d gradually increases in the descending direction, The spring force acting on the pin 8d becomes almost constant.

At the most raised position of the seat cushion 2 shown in FIG. 1 (b), the spring force f of the spiral spring 27 becomes the minimum, but the center of the second rotary shaft 25 (center of the spiral spring 27) The center-to-center distance h from the center of the pin 8d gradually decreases in the upward direction, and the spring force acting on the pin 8d becomes substantially constant.

Thus, as the seat cushion 2 is moved up and down, the spring force of the spiral spring 27 acting on the pin 8b becomes substantially constant, and as shown in FIG.
The operation force of No. 2 becomes almost constant, and the operation feeling is improved.

The first rotary shaft 21 of the sector gear 22
Since the inner end portion 27a of the spiral spring 27 can be locked to the second rotation shaft 25 that is eccentric from the above, it is advantageous in terms of space and the degree of freedom in design is improved.

In the above embodiment, the lift mechanism for raising the rear portion of the seat cushion 2 is used. However, the lift mechanism for raising the front portion of the seat cushion 2 or the lift mechanism for raising the front portion and the rear portion of the seat cushion 2 at the same time is used. It goes without saying that it is also applicable. Further, it goes without saying that the present invention can be applied to a type operated by an electric motor as well as operated by a manual operation dial.

[0027]

As is apparent from the above description, according to the present invention, the center-to-center distance H gradually increases in the descending direction of the seat in which the spring force F of the spiral spring gradually increases and acts on the pin. The spring force acting on the pins becomes substantially constant in the ascending direction of the sheet in which the spring force f of the spiral spring becomes gradually smaller and the spring force f becomes smaller. , The operation force of the sector gear becomes almost constant and the operation feeling is improved. Further, since the inner end portion of the assist spiral spring can be locked to the second rotation shaft that is eccentric from the rotation shaft of the sector gear,
It becomes advantageous in terms of space and the degree of freedom in design is improved.

[Brief description of drawings]

FIG. 1 is a main part of a lift device according to the present invention, in which (a) is a side view of a most lowered position and (b) is a side view of a most raised position.

FIG. 2 is an exploded perspective view of a main part of a lift device.

FIG. 3 is a graph showing a relationship between an operation angle and an operation force of the lift device according to the present invention.

FIG. 4 is a graph showing a relationship between an operating angle and an operating force of a conventional lift device.

FIG. 5 is a conventional seat, (a) is a perspective view,
(B) is a side view of the lift device.

[Explanation of symbols]

1 sheet 2 seat cushion 4 base frame 8d pin 10 Manual dial 21 1st rotating shaft 22 sector gear 25 Second rotating shaft 26 Cam plate 26b Spring hook 26c slot 27 Assist spiral spring 27a inner end 27b outer end F, f Spring force H, h center distance

Claims (2)

[Claims] 1. A lift device provided with a sector gear that is rotated by an operation, and lifting and lowering a seat via a link member linked to the rotation of the sector gear, wherein a second eccentric shaft is eccentric from a first rotation shaft of the sector gear. The cam plate rotated by the rotating shaft and the second of the cam plate
An assist spiral spring having an inner end locked to the rotation shaft and an outer end locked to a cam plate is provided with the cam plate, and a length with which a pin provided on the sector gear is fitted. A hole is formed, and in this elongated hole, the center-to-center distance H between the second rotating shaft and the pin at the seat's lowest position where the spring force F of the spiral spring is maximum is the minimum spring force f of the spiral spring. A seat lifting device, wherein the pin is formed so as to be longer than a center distance h between the second rotation shaft and the pin at the most raised position of the seat. 2. The product of the spring force F and the center-to-center distance h and the product of the spring force f and the center-to-center distance H have a substantially constant relationship,
The seat lifting device according to claim 1, wherein the spring force acting on the pin is substantially constant between the highest position and the lowest position.