JPH0518342U - The seat and backrest cannot be angled. - Google Patents

Abstract

(57) [Abstract] [Purpose] To ensure that the angular displacement of the seat and the backrest is achieved structurally and mechanically simply in a chair that can adjust the tilts of the seat and the backrest that are in parallel with each other. . According to the present invention, in a chair of the above type, a seat portion 11 and a backrest 12 are combined and connected to parallel rotary shafts 14 and 15, and the backrest 12 is a lower portion thereof and a lever arm extending forward under the seat portion. 12a, the seat portion is mounted on a lever arm, and when the backrest is pushed and angularly displaced with the rotating shaft 15 as a fulcrum, the rotating shaft 14 is angularly displaced as a fulcrum.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chair having a seat and a backrest whose angles can be adjusted, and more particularly, to a chair having a seat and a backrest having adjustable angular displacements which are simultaneously advanced in relation to each other.

[0002]

[Prior Art]

 Chairs having a seat and a backrest that are angularly displaceable about a horizontal axis of rotation in relation to one another are already known. The seat of the chair can be angularly displaced stepwise relative to it on a fixed support of the base, while the backrest automatically changes its inclination with respect to the position of the seat. The reverse is also true. The correlation or simultaneous progression of the seat and back angular displacements, which is usually ensured by mechanical devices and contrast springs, complicates the structure of the chair and adds cost.

[0003]

[Problems to be solved by the device]

 An object of the present invention is to provide a simple structure with a simple lever, rather than a mechanical device or a spring, to allow simultaneous angular displacement of the seat or backrest.

[0004]

[Means for Solving the Problems]

 The solution to the above problem is achieved by a chair which substantially corresponds to claim 1 described later.

A person sitting in a chair leans backwards from a vertical posture, for example, a working posture to a relaxed posture, for example, a conversational posture.

The chair according to the present invention is provided with a backrest designed to utilize the weight of a person on a chair by contrast and reaction without relying on a spring to perform a supple angular displacement to the rear. There is. Therefore, the movement of the backrest, which adjusts the tilt and follows the backrest load, always balances the posture and weight of a person sitting in a chair.

In practice, the rearward angular displacement of the backrest is associated with the rearward movement of the seat, which is always under the weight of the seated person. Thus, the total variable angle of seat and back angular displacement corresponds to the sum of the two angle changes of seat and back tilt. This contributes to relieving the load of the spine on the seated person when the lean load shifts from a vertical position to a relaxed position, the effect of which is even more effective and stronger than when the backrest is tilted. Means that.

[0008]

【Example】

 The present invention will be described in more detail with reference to the accompanying drawings showing an example of an embodiment of the present invention.

FIG. 1 is a perspective view of the backside of the seat portion alone, FIG. 2 is a perspective view of the backrest alone, and FIG. 3 is a schematic side view of the seat portion and the backrest combination in a state where a pressing load is applied to the seat portion, FIG. 4 is a schematic side view of the seat portion and the backrest combination in which the backrest is loaded rearward.

The illustrated chair according to the present invention includes a seat portion 11 and a backrest 12 assembled on a support or a base 13 as constituent elements.

The seat portion 11 is pivotally attached to the base 13 on the front side by a first rotating shaft 14 in the transverse direction. On the other hand, the backrest 12 is pivotally attached at its lower portion to the rear portion of the base 13 by a second rotary shaft 15 in the transverse direction. The rotation axis 14 of the seat and the rotation axis 15 of the backrest are parallel to each other.

The backrest 12 has a lower lever arm 12a angled to it. The lever arm 12a moves together with the backrest 12 and swings so that the lever arm 12a can be fixed to the backrest either integrally or by being inserted. The lever arm 12a extends forward below the seat and beyond the rotation axis of the backrest.

When the seat portion and the backrest are combined, the rear portion of the seat portion 11 rests on the lever arm 12a of the backrest, and the seat portion and the backrest can be angularly displaced with their respective shafts 14 and 15 as fulcrums. .. The seat and backrest can be linked by a pocket slot 16 formed on the underside of the seat and adapted to hold the free end of the lever arm 12a.

Therefore, when the weight of the seated person is exclusively and predominantly applied to the seat portion in the direction of arrow F (FIG. 3), the backrest is standing upright over the seat portion on the lever arm. Keep On the other hand, when a seated person moves his / her body backward and applies a force in the direction of arrow G (Fig. 4) to the backrest, the backrest itself leans backward, and the lever arm pushes up the rear portion of the seat portion. This movement of the seat is caused by the weight of the occupant, and correspondingly limits the rearward tilt of the backrest.

However, as described above, the movements of the seat and the backrest are seated together, excluding the load on the backrest, which is a simultaneous interrelation that allows a person on a chair to be in a comfortable posture and state. The person automatically returns to the initial posture (Fig. 3).

[0016]

[Effect of the device]

 As is clear from the above description, the present invention is a chair of the type described at the beginning, and has a simple lever configuration without using mechanical devices or springs. The task of enabling simultaneous progressive angular displacements is achieved.

[Brief description of drawings]

FIG. 1 shows a perspective view of the back side of a seat portion alone.

FIG. 2 is a perspective view of a backrest alone.

FIG. 3 is a schematic side view of a seat portion and a backrest combination under a state where a pressing load is applied to the seat portion.

FIG. 4 is a schematic side view of a seat portion and a backrest combination under a state where a backrest is loaded with a leaning load.

[Explanation of symbols]

 11 Seat Part 12 Backrest 12a Lever Arm 13 Base 14 First Rotating Shaft 15 Second Rotating Shaft 16 Pocket Slot

Claims (3)

[Scope of utility model registration request] 1. A seat portion is pivotally attached to a base on its front side by a first rotating shaft, and a backrest has its lower portion on the base,
Pivoted by a second axis of rotation parallel to the first axis of rotation,
In a chair capable of adjusting the phase of angular displacement in which the seat and the backrest simultaneously move in correlation with each other, the backrest is provided with a lever arm at its lower portion, which extends forward under the seat at an angle with respect to the backrest. Is pushed and angularly displaced about the second rotation axis as a fulcrum, the seat portion is angularly displaced about the first rotation axis while being mounted on the lever arm. The chairs. 2. The lever arm, which is integral with or fixed to the backrest, extends forward below the seat beyond the second axis of rotation, and when the backrest is pushed and tilts rearward, The chair according to claim 1, wherein the lever arm is adapted to apply a force to push the lower surface of the seat portion upward from the bottom. 3. The chair according to claim 1, wherein the lever arm has a free end inserted into a pocket slot formed on the lower surface of the seat portion.