JP3585013B2 - Support structure for backrest in chair - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a support structure for a backrest in a chair.
[0002]
[Prior art]
In order to be able to support the upper body in a stable state without straining the lumbar spine and spinal cord when rocking, the back of the chair is supported by a back support that supports the back of a person and a waist support that supports the waist It has been considered that the waist support is made to protrude forward with respect to the back support at the time of rocking when a person leans on the backrest.
[0003]
For example, Japanese Patent Application Laid-Open Nos. 7-95911, 7-95913, and 7-155233, which are filed by the applicant of the present application, disclose a supporting frame fixed to the upper end of a leg. A guide member extending toward the back of the waist support is fixed to the waist support, and the guide function of the guide member is used to deform the waist support in a side view in conjunction with the backward tilt of the back support. Is disclosed.
[0004]
Further, Japanese Patent Application Laid-Open No. 7-155232 discloses that the waist support portion is configured to be flexibly deformable in a plan view, and the guide member and the waist support portion are set so as to hit the right and left ends first. It is disclosed that the waist support 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.
[0005]
On the other hand, similarly to the above-mentioned publications, JP-A-7-163436 and JP-A-7-184741 according to the prior application of the present applicant use an elastic member which deforms in conjunction with the backward tilting of the back support. It is disclosed that the waist support is projected forward.
[0006]
[Problems to be solved by the invention]
However, in a configuration using a fixed guide member as disclosed in JP-A-7-95911, JP-A-7-95913, and JP-A-7-155233, the waist support is stretched in a side view at the time of locking. Therefore, the locking operation may not be smooth. 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 excessively forward, so that an appropriate support state cannot be obtained.
[0007]
On the other hand, when the waist support is pushed out using an elastic member as disclosed in JP-A-7-163436 and JP-A-7-184743, return deformation of the elastic member due to the reaction force of the body at the time of locking is prevented. Therefore, it is necessary to make the elastic force of the elastic member difficult to be deformed, so that the smooth back tilting of the backrest is hindered, and the smooth back tilting of the backrest and the appropriate support of the body are prevented. They were in conflict.
[0008]
The present invention allows a simple structure to move the waist support relative to the back support smoothly with a simple structure in forming the backrest into the back support and the waist support and moving them relative to each other during locking. It is intended for that purpose.
[0009]
[Means for Solving the Problems]
In order to achieve this object, in the present invention,
`` A seat attached to a support frame provided at the upper end of the leg, and a backrest that tilts rearward against elastic support means such as a spring 13, wherein the backrest is a back support that supports a person's back. A chair comprising a waist support for supporting a human waist, wherein the waist support is formed so as to be able to protrude forward relative to the back support and bendable and deformable in a forward concave shape in plan view. At
The back support is attached to a first tilt body pivotally attached to the support frame and the seat so as to be tiltable rearward, and a second tilt body extending toward the back of the waist support is attached to the seat and the support frame. The first tilting body and the second tilting body are pivotally attached to each other via a link so that the second tilting body relatively tilts forward when the first tilting body tilts rearward. The second tilting body abuts against the back of the waist support. "
Was configured.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment 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 line III-III of FIG. 1, FIG. 4 is a sectional view taken along line IV-IV of FIG. 1, and FIG. 6 is a sectional view taken along line VI-VI in FIG. 1, FIG. 7 is a longitudinal sectional side view in a locking state, and FIG. 8 is a sectional view taken along line VIII-VIII in FIG.
[0011]
The chair includes a leg 1, a support frame 2 fixed to an upper end of the leg 1, a cushioned seat 3 attached to the support frame 2, and a cushioned backrest 4, and the seat 3 is a seat. It is fixed to the receiver 5.
As shown in FIGS. 3 and 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 receiver 5 is disposed inside the left and right side plates 2 a of the support frame 2 in front view, and the side plate of the seat receiver 5 is attached to the front end of the side plate 2 a of the support frame 2. It is pivotally connected 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. Therefore, the seat body 3 can retreat while tilting rearward.
[0012]
The backrest 4 includes a back support 8 for supporting the back of the person and a waist support 9 for supporting the waist of the person. The back support 8 has a substantially L-shape in side view. It is fixed to the upper part of the formed first tilting body 10.
The front end of the first tilting body 10 projects downward, and a vertically intermediate portion of the downward projection 10 a is pivotally attached to the side plate 2 a of the support frame 2 by the second shaft 11. Further, the front end of the horizontal portion of the first tilting body 10 is pivotally attached to the seat receiver 5 by the third shaft 12. As shown in FIG. 1 partially 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.
[0013]
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 in conjunction with this, the seat body 3 moves the first pivot hole 7 It will be tilted backward while being guided backward by the guide.
A front end of a second tilting body 14 formed in an L-shape in a side view is pivotally attached to the seat receiver 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 of the upper end, pressing portions 15 that contact the back surface of the waist support portion 9 projecting forward.
[0014]
The pressing portion 15 may be brought into contact with the waist support portion 9 in the non-locking state, or some gap may be provided between the pressing portion 15 and the waist support portion 9 in the non-locking state. Alternatively, the pressing portion 15 may be brought into contact with the waist support portion 9 during the backward tilt of the backrest 4. Further, a spring means may be interposed between the pressing portion 15 of the second tilting body 14 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.
[0015]
The back support portion 8 and the waist support portion 9 each have a structure in which a cushion is provided on a substrate (shell) 15 made of synthetic resin or the like, and the back support portion 8 is attached to the first tilting body 10, and It is in a state where it does not bend and deform.
Further, the substrate 16 of the back support portion 8 and the waist support portion 9 are integrally connected via a narrow portion 16a. Therefore, the waist support portion 9 can protrude forward relative to the back support portion 8 by bending and deforming the bridge portion 16a. Further, the waist support portion 9 is formed to have a bending strength capable of bending and deforming in a concave shape facing forward in plan view. The back support 8 and the waist support 9 may be connected by a rotatable connection tool such as a hinge or may be pivotally connected by a pin.
[0016]
The horizontal portion of the second tilting body 14 and the support frame 2 are connected to each other by a link 19 pivotally connected to the fourth frame 17 and the fifth shaft 18 so as to be able to rotate back and forth.
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 body 3 also moves to the first tilting position. It is guided by the pivot hole 7 and tilts backward while moving backward. Further, the second tilting body 14 also tilts backward 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 rearward tilting of the second tilting body 14 is suppressed, whereby the waist support 9 is moved relative to the back support 8. Protruding forward.
[0017]
Then, the waist support portion 9 is pressed from the back by the pressing portion 15 of the second tilting member 14, but since the left and right pressing portions 15 of the second tilting member 14 are wide, as shown in FIG. The waist support portion 9 bends and deforms in a concave shape facing forward in plan view. As a result, a state in which the waist of the person is wrapped in the waist support portion 9 is provided, 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 as compared with the time of non-locking, in other words, the second tilting body 15 also moves backward and tilts in conjunction with the first tilting body 10. Although the simple structure in which the pressing portion 15 of the second tilting body 14 is merely applied to the back of the waist support portion 9, the waist support portion 9 does not protrude excessively, and can appropriately support the upper body of a person. .
[0018]
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 lower the pressing portion 15 moves downward, the smaller the projecting amount), or the link. The position of the link 19 can be freely adjusted (by retreating the position of the link 19, the backward tilt of the second tilting body 14 is suppressed, so that the forward projection amount increases).
[0019]
In the above-described embodiment, the pair of left and right pressing portions 15 is provided on the second tilting body 10. However, a plurality of pairs of pressing portions 15 may be arranged such that the protrusion dimension increases toward the left and right outer sides. Alternatively, the pressing portion 15 may be formed in a concave shape facing forward in a plan view.
As shown in a modification of FIG. 9, the pressing portion 15 of the second tilting member 10 is formed in a simple flat plate extending linearly in a 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.
[0020]
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 a seat body does not tilt backward or retreat.
[0021]
Effects of the Invention
As described above, according to the present invention, the waist support is relatively protruded forward by the second tilting body that rotates in conjunction with the backward movement of the back support, so that the configuration is very simple. However, the waist support can protrude forward by an appropriate amount relative to the back support. Further, since the waist support portion is not forcibly stretched and deformed, the locking operation is smooth.
[0022]
Therefore, 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, 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. 1;
FIG. 7 is a longitudinal sectional side view in a locking state.
8 is a sectional view taken along line VIII-VIII in 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)

A seat 3 attached to a support frame 2 provided at the upper end of the leg 1 and a backrest 4 which tilts backward against elastic support means such as a spring 13 are provided, and the backrest 4 supports a human back. It comprises a back support portion 8 and a waist support portion 9 for supporting the waist of the person, and the waist support portion 9 is capable of protruding forward relative to the back support portion 8 and is bent in a forward concave shape in plan view. In a chair formed to be deformable,
The back support 8, while attached to the first tilting member 10 which is pivoted freely rear tilting the support frame 2 and the seat body 2, the seat body 3 and the support frame 2, towards the back of the lumbar support 9 The second tilting body 14 is extended forward and backward so as to be freely tiltable. When the first tilting body 10 tilts rearward, the second tilting body 14 relatively moves forward. A support structure for a backrest in a chair, characterized in that the second tilting member (14) abuts on the back of the waist support portion (9) by being linked via a link (19) so as to tilt. In "claim 1", the one second or Re tilting member 14 and the lumbar support 9 noise or both, forward lumbar supporting portion 9 in a plan view by the pressing action of the pressing portion 15 against the lumbar support 9 A support structure for a backrest in a chair, wherein a pressing portion 15 is formed so as to be bent and deformed in a concave shape. In claim 1 or claim 2, the front seat 3 is attached to the support frame 2 so as to be capable of retreating and tilting rearward, and the first tilting body 10 and the seat 3 are connected to each other by the first tilting body 10. the seat body 3 when the rear tilting interlockingly connected to the rear tilt while retraction together, further, pivoted freely tilted backward movement of the second tilting member 14 to the seat support 3, a second tilting member 14 A support structure for a backrest in a chair, wherein the support frame 2 is connected to the second tilting body 14 and a link 19 pivotally connected to the support frame 2 so as to be able to rotate back and forth.

Images