JPH10179313A - Structure for supporting back rest of chair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize through a simple structure a comfortable rocking state by deforming a waist supporting part into a recessed part facing forward. SOLUTION: This supporting structure is such that the seat 3 is installed, so as to make its backward retreat and tilt freely, in the slit 7 of the supporting frame 2 by means of the first axis 6, with the first tilting body 10 for attaching a back support 8 pivotally attached to the supporting frame 2 and the seat support 5 by means of the second 11 and third 12 are interlocked with a link 19, with the backward inclination of the second tilting body 14 suppressed by the link 19. A pair of pressurizing parts 15 separated left and right are projectingly provided facing forward on the upper end of the second tilting body 14. At the time of rocking, the waist supporting part 9 is supported at two points with the left and right pressurizing parts 15; it is, therefore, deflected and deformed in a forwardly recessed shape in the plane view in the manner of enveloping the waist.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support structure for a backrest in a chair.

[0002]

2. Description of the Related Art In a chair, in order to support the upper body in a stable state without placing a burden on a lumbar spine or a spinal cord at the time of rocking, a backrest of a chair is supported by a back support portion supporting a human back and a waist. It has been considered that the lumbar support portion is configured to support the lumbar support portion so that the lumbar support portion protrudes forward relative to the back support portion at the time of rocking when a person leans on the backrest.

[0003] As a specific means, for example, JP-A-7-95911, JP-A-7-95913, and JP-A-7-155233, which are filed by the applicant of the present application, disclose a method in which A guide member extending toward the back surface of the waist support portion is fixed to the support frame thus formed, and the waist support portion is extended in a side view in conjunction with the backward tilt of the back support portion by utilizing the guide action of the guide member. It is disclosed to be modified as follows.

Further, in Japanese Patent Application Laid-Open No. Hei 7-155232, the waist support is configured to be flexibly deformable in a plan view so that the guide member and the waist support come into contact with both right and left ends first. Accordingly, it is disclosed that the waist support portion is configured to be deformed into a concave shape facing forward when viewed from above when locking. With this configuration, the waist of the person is wrapped in the waist support, so that a more comfortable locking state can be obtained.

On the other hand, as in the above-mentioned publications, Japanese Patent Application Laid-Open Nos. Hei 7-163436 and Hei 7-84741 filed by the applicant of the present application disclose an elastic member which deforms in conjunction with the backward tilting of the back support. U.S. Pat.

[0006]

However, Japanese Patent Laid-Open No. 7-9591
In the configuration using a fixed guide member as disclosed in JP-A-7-95913, JP-A-7-95913, and JP-A-7-155233, the waist support is stretched in a side view at the time of locking. However, the locking operation may not be smooth. In addition, if the guide member is of a fixed type, simply supporting the back surface of the waist support portion with the guide member will cause the waist support portion to protrude forward too much, so that an appropriate support state cannot be obtained.

On the other hand, JP-A-7-163436 and JP-A-7-18
In the method in which the waist support is pushed out using an elastic member as disclosed in Japanese Patent No. 4741, the elastic force of the elastic member is hardly deformed in order to prevent the elastic member from returning due to the reaction force of the body at the time of locking. This would impede the smooth back tilting of the back, and the smooth back tilting of the back and proper support of the body would conflict.

According to the present invention, when the backrest is formed in the back support and the waist support and these are relatively moved at the time of locking, the waist support can be smoothly moved relative to the back support with a simple structure. The purpose is to do so.

[0009]

According to the present invention, to achieve this object, the present invention provides a "seat body attached to a support frame provided at the upper end of a leg, and a rearward tilt against a resilient support means such as a spring 13". Comprising a backrest, the backrest comprises a back support for supporting the back of a person and a waist support for supporting the waist of the person, and the waist support is directed forward relative to the back support. In a chair which is formed so as to be able to protrude and bendable in a concave shape facing forward in a plan view, the back support portion is attached to a first tilting body pivotally attached to the support frame or a seat body so as to be tiltable rearward. When a second tilting body extending toward the back of the waist support portion is pivotally attached to the seat body or the support frame so as to be able to tilt forward and backward, and the first tilting body and the second tilting body are tilted rearward when the first tilting body tilts rearward. The link is connected via the link so that the second tilting body relatively tilts forward. Allowed, and the configuration of the contact to the back of the lumbar support "the second tilting member.

[0010]

Next, embodiments of the present invention will be described with reference to the drawings. 1 is a longitudinal side view of the chair, FIG. 2 is an exploded view of the members, FIG. 3 is a sectional view taken along the line III-III of FIG. 1, and FIG.
5, FIG. 5 is a rear view as viewed in the direction VV in FIG. 1, FIG. 6 is a cross-sectional view as viewed in the direction VI-VI in FIG. 1, FIG. 7 is a vertical sectional side view in the locking state, and FIG. It is VIII sectional drawing.

The chair includes a leg 1, a support frame 2 fixed to the upper end of the leg 1, a cushioned seat 3 attached to the support frame 2, and a cushioned backrest 4. Reference numeral 3 is fixed to the seat receiving body 5. FIG.
As shown in FIGS. 4 to 4, the support frame 2 is formed in an open U-shape when viewed from the front. Similarly, as shown in FIGS. 3 and 4, the seat receiving body 5 is a left and right side plate of the support frame 2 in a front view.
The side plate of the seat receiver 5 is pivotally connected to the front end of the side plate 2a of the support frame 2 by a horizontal first shaft 6. In this case, the first pivot hole 7 of the support frame 2 in which the first shaft 6 is fitted is formed as an elongated hole extending horizontally in a side view. Accordingly, the seat body 3 can retreat while tilting rearward.

The backrest 4 comprises a back support 8 for supporting the back of a person and a waist support 9 for supporting the waist of the person. The back support 8 is substantially L in side view. It is fixed to the upper part of the first tilting body 10 formed in a character shape. First
The front end of the tilting body 10 protrudes downward, and a vertically intermediate portion of the downward protruding portion 10 a is pivotally attached to the side plate 2 a of the support frame 2 by a second shaft 11. Further, the front end of the horizontal portion of the first tilting body 10 is pivotally connected to the seat receiver 5 by a third shaft 12. As shown partially in FIG. 1 by a dashed line, the downwardly protruding portion 10a of the first tilting body 10 is supported from the front by a spring 13 as an example of elastic support means.

Therefore, when a person leans on the backrest 4, the first tilting body 10 tilts rearward about the second shaft 11 against the spring 13, and the seat 3 moves in the first pivotal position in conjunction with this. Support hole 7
It will be tilted backward while being moved backward by being guided by. A front end of a second tilting body 14 formed in an L shape in side view is pivotally attached to the seat receiving body 5 by the third shaft 12 so as to be tiltable back and forth. The second tilting body 14 extends toward the back surface of the waist support portion 9, and has, at the left and right sides on the upper end, pressing portions 15 that hit the back surface of the waist support portion 9 projecting forward.

The pressing portion 15 may be brought into contact with the waist support portion 9 in the non-locking state, or a slight gap may be provided between the pressing portion 15 and the waist support portion 9 in the non-locking state. In this case, the pressing portion 15 may be brought into contact with the waist support portion 9 while the backrest 4 is tilted backward. Further, the second tilting body 14
A spring means may be interposed between the pressing portion 15 and the waist support portion 9. Further, the pressing portion 15 may be engaged with the waist support portion 9 by means such as pinning.

The back support 8 and the waist support 9 each have a structure in which a cushion is provided on a board (shell) 15 made of synthetic resin or the like. The back support 8 is attached to the first tilting body 10. And is in a state where it is hardly bent and deformed. Further, the substrate 16 of the back support 8 and the waist support 9 has a narrow width portion 16a.
Are connected together through. Therefore, the bridge portion 16a
Is bent and deformed, whereby the waist support portion 9 becomes a back support portion 8.
Relative to the front. Furthermore, the waist support 9
Is formed to have a bending strength capable of bending and deforming in a forward concave shape in plan view. In addition, the back support part 8 and the waist support part 9
It may be connected by a rotatable connection tool such as a hinge or may be pivotally connected by a pin.

The horizontal portion of the second tilting member 14 and the support frame 2 are linked to each other by a link 19 pivotally connected to the support frame 2 by means of a fourth shaft 17 and a fifth shaft 18. In the above configuration, as shown in FIG. 7, when a person leans on the backrest 4, the back support portion 8 and the first tilting body 10 tilt backward integrally, and in conjunction with this, the seat 3 also moves to the first tilting position. It is tilted rearward while being retracted and guided by the pivot hole 7. Further, the second tilting body 14 also tilts rearward in conjunction with the first tilting body 10. In this case, since the link 19 is in a state of being stretched on the second tilting body 14, the backward tilting of the second tilting body 14 is suppressed, so that the waist support portion 9 moves relative to the back support portion 8. Protruding forward.

Then, the waist support portion 9 is pressed from the back by the pressing portion 15 of the second tilting member 14.
Because the interval between the left and right pressing portions 15 is wide, as shown in FIG.
The waist support portion 9 bends and deforms in a forward concave shape in plan view. As a result, the waist of the person is wrapped around the waist support 9, and a more comfortable locking state can be provided. Further, since the absolute position of the second tilting body 14 at the time of locking is retracted compared to the time of non-locking, in other words, the second tilting body 15
Also moves backward and backward in conjunction with the first tilting body 10,
With a simple structure in which the pressing portion 15 of the second tilting body 14 is just applied to the back of the waist support portion 9, the waist support portion 9 does not protrude excessively, and the upper body of the person can be properly supported.

The degree to which the waist support portion 9 protrudes forward relative to the back support portion 8 can be changed by changing the height position of the pressing portion 15 (the more the pressing portion 15 moves downward, the smaller the protruding amount becomes). ), Can be freely adjusted by changing the position of the link 19 (the second position is obtained by retreating the position of the link 19).
Since the backward tilt of the tilting body 14 is suppressed, the forward projection amount increases).

In the above-described embodiment, a pair of left and right pressing portions 15 is provided on the second tilting body 10, but a plurality of pairs of pressing portions 15 are provided.
May be arranged such that the protrusion dimension increases toward the left and right outer sides, or the pressing portion 15 may be formed to have a concave shape facing forward in plan view. As shown in a modification of FIG. 9, the pressing portion 15 of the second tilting member 10 is formed as a simple flat plate extending linearly in plan view, while the second tilting member 14 is provided on the back of the waist support portion 9. A pair (or a plurality of pairs) of pressing portions 15 may be formed.

Further, a plurality of vertically long slits may be formed in the waist support portion so as to be more easily deformed.
Further, the present invention can be applied to a chair in which the seat body does not tilt backward or retreat.

[0021]

As described above, according to the present invention, the waist support is relatively protruded forward by the second tilting body which rotates in conjunction with the retraction of the back support. Although the configuration is very simple, the waist support can protrude forward relative to the back support by an appropriate amount. Further, since the waist support portion is not forcibly stretched and deformed, the locking operation is also smooth.

Accordingly, it is possible to achieve a comfortable locking state by fitting the backrest to the upper body of the person with a simple structure. Further, according to the second aspect of the present invention, since the waist of the person is wrapped by the waist support in the locking state, a more comfortable locking state can be obtained. Further, according to the twenty-third aspect, the distance between the seat body and the backrest can be maintained in an appropriate state, so that a more comfortable locking state can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a chair according to a first embodiment.

FIG. 2 is an isolated side view of a member.

FIG. 3 is a sectional view taken along line III-III of FIG.

FIG. 4 is a sectional view taken along line IV-IV of FIG.

FIG. 1 is a rear view as viewed from the line VV.

FIG. 6 is a sectional view taken along line VI-VI of FIG.

FIG. 7 is a longitudinal sectional side view in a locking state.

FIG. 8 is a sectional view taken along line VIII-VIII of FIG. 7;

FIG. 9 is a plan sectional view showing a modification.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Leg 2 Support frame 3 Seat 4 Backrest 5 Seat support 8 Back support 9 Waist support 10 First tilting body 13 Spring 14 Second tilting body 15 Pressing part

Claims (3)

[Claims] 1. A seat 3 attached to a support frame 2 provided at an upper end of a leg 1, and a backrest 4 which tilts rearward against an elastic support means such as a spring 13; A back support portion 8 for supporting the back of the user and a waist support portion 9 for supporting the waist of the person, and the waist support portion 9 can protrude forward relative to the back support portion 8 and can be viewed in plan. The back support portion 8 is attached to the support frame 2 or the first tilting body 10 pivotally attached to the seat body 2 so as to be tiltable rearward, while the seat body is formed. A second tilting body 14 extending toward the back surface of the waist support 9 is pivotally attached to the support frame 3 or the support frame 2 so as to be able to tilt forward and backward, and these first tilting body 10 and the second tilting body 14 are connected to the first tilting body. When the second tilting body 14 tilts forward relative to the second tilting body 10 via the link 19, The support structure of the backrest in the chair, characterized in that in contact with the second tilting member 14 on the back of the waist support 9. 2. The method according to claim 1, wherein the second tilting member 14 is provided.
A pressing portion in which one or both of the pressing portion 15 and the waist supporting portion 9 are deformed so that the waist supporting portion 9 is bent forward and concave in a plan view by a pressing action of the pressing portion 15 on the waist supporting portion 9. 15. A support structure for a backrest in a chair, characterized in that it forms 15. [Claim 3] In claim 1 or claim 2,
The front seat 3 is attached to the support frame 2 so as to be able to retreat and tilt backward, and the first tilting body 10 and the seat 3 are connected to the first tilting body 10.
Is tilted rearward, the seat body 3 is interlockingly connected so as to tilt backward while retreating together, and further, the second tilting body 14 is pivotally attached to the seat body 3 so as to be tiltable rearward and the like. And a support frame 2 connected to the second tilting member 14 and the support frame 2 by a link 19 rotatably pivotally movable back and forth.