JPH11113668A - Chair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To recline a back rest with proper force and return surely the seat and back rest into their original positions when the back rest is released from the load. SOLUTION: A back-receiving flame 7 is supported on the back support part 5c of a support flame 5 fixed to legs 2, so as to be movable upward/ downward and turnable. And slide guide blocks 8d and 8e are turnably attached to a seat support part 5b. In a seat-receiving frame 6, a front guide rail 6a extending horizontally toward the front and rear and a rear guide rail 6b extending obliquely upward, the front higher and the rear lower, are formed. After the seat-receiving flame 6 is slidably supported by fitting the slide guide blocks 8d and 8e into the front and rear guide rails 6a and 6b, the front end of the curved rod 7b of the back-receiving fine 7 and the connection part 6d of the seat-receiving frame 6 are freely turnably connected with a connecting pin 14a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chair in which a backrest and a seat are locked in conjunction with each other.

[0002]

2. Description of the Related Art In a chair (for example, an office chair) provided with a locking mechanism for tilting a backrest by applying a backrest load, when the backrest tilts backward, the front end of the seat is prevented from rising and the seat is lifted. Is known in which the user is moved forward to maintain good sitting comfort. In addition, a return spring is provided for returning the backrest and the seat to the original posture when the backrest load is released.

[0003]

In such a chair,
If a return spring with a large spring constant is used to quickly return the seat with the seated person's weight to the original position when the backrest load is released, a large force will be applied when the backrest is tilted backward. Required. On the other hand, if a return spring having a small spring constant is used so that the backrest can be tilted backward with a light force, the restoring force of the seat tends to be insufficient.

The present invention has been made in order to solve the above-mentioned problem, and it is possible to tilt the backrest backward with an appropriate force, and to surely return the seat and the backrest to the original posture when the backrest load is released. An object of the present invention is to provide a chair that can be returned.

[0005]

In order to achieve this object, the following chair has been created. That is, in the first invention, the main body frame of the leg is provided with the seat frame that can move in the front-rear direction and the back frame that can swing back and forth, and is tilted backward by the backrest load of the seated person. A chair in which a seating frame and a backing frame are connected so that the backing frame pushes the seating frame substantially forward, and a chair is provided between the main body frame and the seating frame in front of the seating frame. A front guide rail for guiding the portion in the front-rear direction so as to be rotatable about a substantially horizontal axis, and a rear guide rail for guiding the rear portion of the seat frame obliquely upward so as to be lifted as the seat frame advances. And a spring for urging the seat receiving frame rearward with respect to the main body frame.

In the chair configured as described above, when the occupant tilts the back of the chair backward, the seating frame is pushed substantially forward in conjunction with the backing frame. At this time, the front part of the seat receiving frame is guided by the front guide rails to move forward, and the rear part of the seat receiving frame is guided by the rear guide rails to move obliquely forward and upward, so that good sitting comfort is maintained. Then, when the backrest load is removed, such as when the seated person raises his back,
Since the force lifting the rear portion of the seat frame, that is, the rear end of the seat (seat), is released, the weight of the occupant trying to push down the rear portion of the seat frame and the urging force of the spring are combined with the backrest. And the seat returns to the original position easily and securely.

[0007]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a partially cutaway perspective view of the chair, and FIG. 2 is an exploded perspective view of the chair with the cushion removed.
As shown in FIG. 1, a chair (such as an office chair) 1 includes a leg 2, a seat (seat) 3, and a backrest 4. The seat 3 and the backrest 4 are connected via a connecting mechanism described below, and the seat 3 moves back and forth in conjunction with the tilting of the backrest 4 in the front-back direction. The details will be described below.

As shown in FIG. 2, a base 2a is attached to the upper end (also referred to as a foot) of a column of a leg 2 having casters, and left and right support frames 5, 5 are provided at both left and right ends of the base 2a. Are fixed respectively by fixing means such as welding. The support frame 5 is formed by bending a steel pipe into a substantially L-shape. A seat support portion 5b extending substantially horizontally in the front-rear direction supports the seat receiving frame 6, and a back support portion 5c that rises at a substantially right angle from the seat support portion 5b. Back frame 7
Has come to support. The support frame 5 is a main body frame according to the present invention.

The seat receiving frame 6 is formed, for example, by pressing a steel plate into the shape shown in the figure, and has a front guide rail 6a extending horizontally at positions near the front end on both left and right sides (specifically, in this example, a long guide rail 6a). A hole is formed, and a rear guide rail 6b (specifically, a long hole) extending obliquely upward is formed at a position near the rear end. In addition, the inclination direction of the rear guide rail 6b, that is, the shape of the long hole is formed obliquely upward (front height) where the front edge of the long hole is higher than the rear edge as shown in the figure.

Then, bolt-shaped mounting members 8a, 8b and nuts 8c, 8 are provided on the side of the seat support portion 5b of the support frame 5.
The slide guide blocks (guide bodies) 8d, 8e rotatably supported via the front and rear guide rails 6a, 6
It is fitted so that it can slide with respect to b. In other words, the movement direction of the seat receiving frame 6 is regulated by the guide portion composed of the front guide rail 6a and the slide guide block 8d and the rear guide rail 6b and the slide guide block 8e, so that the seat receiving frame 6 can slide substantially in the front-rear direction. Supported. Note that, contrary to this example, a guide rail may be provided on the support frame 5 side, and a slide guide block (guide body) may be provided on the seat receiving frame 6 side.

The other end of the spring (tensile spring) 9 having one end attached to the head of the attachment 8b is attached to a spring support 6c provided on the seat receiving frame 6, and the seat receiving frame 6 is provided. 6 is urged rearward with respect to the support frame 5, and the spring 9 is extended when the seat receiving frame 6 slides forward. In FIG. 2, the front and rear guide rails, slide guide blocks, springs, and the like are shown on only one side (right side toward the chair), and the other (left side) is not shown. Is symmetrical.

The seat shell 10 disposed between the seat frame 6 and the base 2a is lifted by bolts 10b screwed into the mounting portion 10a.
It is fixed to. The seat shell 10 has a narrow slit 10c through which the mounting leg 5a of the support frame 5 passes,
A hole 10d is formed through the back support portion 5c of the support frame 5 so that the seat receiving frame 6 and the seat shell 10 can be integrally moved with respect to the support frame 5.

On the other hand, a resin-made slide rail member 11a is attached to an elongated hole 7a formed on the side of the back receiving frame 7 so as to extend substantially vertically, and is attached to the back support portion 5c of the support frame 5. A pin 11b extending in the horizontal direction is inserted into the slide rail member 11a, and the back receiving frame 7 is supported so as to be rotatable around a horizontal axis and slidable in a substantially vertical direction. The tip of the pin 11 a is prevented from falling off by a retaining ring 11 c, and a back shell 12 is attached to the back side of the back support frame 7. Reference numeral 12a in the figure denotes a bolt for fastening the back support frame 7 and the back shell 12. Although the left and right back frames 7, 7 are provided in this example, they may be integrated. Further, the back support portion 5c of the support frame 5 is connected to the back support frame 7 while penetrating the hole 12b of the back shell 12.

The distal end of the curved rod 7b extending downward from the back support frame 7 is rotatably connected to a connecting portion 6d protruding from the rear portion of the seat receiving frame 6 via a connecting pin 14a. A retaining ring 14b is attached to the tip of 14a. The back support portion 5c of the support frame 5 and the curved rod 7b of the back support frame 7 are covered with a bellows-like frame cover 13 so as to be hidden from view from outside. In frame 7,
As shown in FIG. 1, the chair 1 is assembled with the cushions 3a and 4a attached.

Next, the operation of the locking mechanism of the chair 1 configured as described above will be described. FIG. 3 shows a state before locking, and FIG. 4 shows a locking state in which the backrest tilts backward. In FIG. 3, the seat frame 6
It is located at the rearmost position on the right end in the drawing by the action of a spring 9 attached between the attachment 8b supported on the support frame 5 and the spring support 6c of the seat receiving frame 6. At this time, the slide guide block 8d is located near the front end of the front guide rail 6a,
Are located near the front end of the rear guide rail 6b. In this state, the cushion 3 supported by the seat frame 6
The upper surface of a, that is, the seating surface (seat surface) is substantially horizontal.

When the occupant leaves his / her upper body on the backrest 4 of the chair 1 and pushes it later, the backing frame 7
And is slightly pushed down. That is, the back support frame 7 is connected to the back support 5 c of the support frame 5.
And the pin 11b is displaced in the longitudinal direction of the elongated hole 7a with respect to the pin 11b, and the backrest load received by the back receiving frame 7 is curved with the pin 11b as a fulcrum. It is transmitted from the tip of the rod 7b to the connecting portion 6d and pushes the seat receiving frame 6 obliquely upward. The front portion of the seat receiving frame 6 is pushed straight forward because the front guide rail 6a engaging with the slide guide block 8d extends substantially horizontally, while the rear portion of the seat receiving frame 6 is connected to the slide guide block 8e. After the engagement, the guide rail 6b extends obliquely upward and is pushed forward obliquely upward. That is, chair 1
The seat 3 slides forward against the pulling force of the spring 9, and the rear end of the seat 3 is lifted obliquely. In addition, the front part of the seat receiving frame 6 is
The rear guide rail 6b is formed so as to maintain an obliquely upward (front high) state even after slightly turning around a and slightly lifting the rear part.

In this manner, the seat 3 slides forward at the same time as the backrest 4 tilts backward, and the buttocks of the occupant move forward, so that good sitting comfort is maintained. It is preferable that the rear end of the seat 3 is slightly lifted and the front end is lowered in a direction in which the feeling of pressure on the back of the thigh of the seated person is reduced.
At this time, the inclined seat 3 promotes the sliding of the seat receiving frame 6 forward by the component force of the seating load acting along the seat surface. Further, when the weight of the occupant is heavy, the backrest load is increased, so that the rear portion of the seat is lifted up without any problem, so that the user does not feel any discomfort due to the difference in weight.

When the occupant lifts his / her back to remove the backrest load, the force lifting the rear portion of the seat receiving frame 6, ie, the rear end of the seat 3 (seat), is released. (Weight) pushes down the rear part of the seat receiving frame 6 to relatively slide the rear guide rail 6b and the slide guide block 8e. Further, since the pulling force of the spring 9 also acts, the backrest 4 and the seat 3 are restored to their original positions. Return to the position (see FIG. 3) simply and reliably.

In the locking mechanism of the chair 1 described above, the seating load is used for the restoring force of the seat frame 6, so that the spring constant of the spring 9 is set relatively small so that the backrest can be tilted backward with an appropriate force. can do. And
Since it is not necessary to return the seat where the person with the heavy weight sits back only by the urging force of the spring as in the related art, the inconvenience that the seat 3 is difficult to return when the weight of the seated person becomes heavy is avoided. That is, it is possible to manufacture a chair having a good usability provided with a locking mechanism having a relatively simple configuration.

[0020]

As described above, according to the present invention,
The seat can be slid forward by tilting the backrest of the chair backward with an appropriate force, and the seat and the backrest can be reliably returned to the original posture when the backrest load is released. Accordingly, there is an effect that the feeling of use (comfort) of the chair can be improved by the locking mechanism having a relatively simple configuration.

[Brief description of the drawings]

FIG. 1 is a partially sectional perspective view of a chair according to an embodiment.

FIG. 2 is an exploded perspective view of the chair according to the embodiment.

FIG. 3 is a sectional view of a main part of the chair, showing a state before locking.

FIG. 4 is a sectional view of a main part of the chair, showing a rocking state in which a backrest is tilted backward.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chair 2 Leg part 3 Seat part 4 Backrest 5 Support frame (body frame) 6 Seat receiving frame 6a Front guide rail 6b Rear guide rail 6d Connection part 7 Back support frame 8d, 8e Slide guide block 9 Spring 11b Pin 14a Connection pin

Claims (1)

[Claims] 1. A backrest frame which is provided on a body frame of a leg head and which is provided with a backrest frame movable in the front-rear direction and a backrest frame swingable back and forth, and which is tilted rearward by a backrest load of a seated person. Is a chair in which a seat receiving frame and a back receiving frame are connected so as to push the seat receiving frame substantially forward, and a front part of the seat receiving frame is substantially provided between the main body frame and the seat receiving frame. A front guide rail that guides in the front-rear direction while being rotatable about a horizontal axis, a rear guide rail that guides the rear part of the seating frame obliquely upward so as to be lifted as the seating frame advances, A chair provided with a spring for urging the seat frame rearward with respect to the main body frame.