JP3508940B2 - Chair with backrest - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chair having a backrest that tilts backwards against the elasticity of a spring or the like.

[0002]

2. Description of the Related Art As a prior art relating to a chair having a backrest which can be tilted rearward, US Pat. No. 4,685,733 discloses a backrest including a back support portion for supporting a person's back and a waist support portion for supporting a waist. And the person leans against the back support
When Ru Kaka, the invention lumbar support portion is such that relatively forward projecting against the back support portion is described.

According to this prior art, since the supporting area by the backrest is increased and the load applied to the spinal cord in the locked state can be reduced, the comfort in the locked state can be improved.

[0004]

By the way, a person's waist (buttock) is gently curved backward in a convex shape in a plan view. However, in the prior art, since the hip support portion is simply projected forward relative to the back support portion, only a narrow range of the left and right central portions of the person's hip (buttock) is supported. Therefore, there is a limit to improving the comfort of the rocking state.

According to the present invention, when the backrest is formed by the back support portion and the waist support portion so that the waist support portion projects forward relative to the back support portion, the backrest leans against the backrest. The purpose is to further improve the comfort in a hanging state.

[0006]

SUMMARY OF THE INVENTION To achieve this object the present invention, the backrest of the rear tilted while being bullet sexually support, constituted by a back support portion and the lumbar support, seat support or seat Receiving
To the back of the back support , tilt the back support to the front.
Guide that projects forward relative to the back support
A chair whose body is provided so as to extend behind the waist support portion.
A child, the back of the waist support of the backrest
When viewed from the front, in the central part and the parts on both the left and right sides, backward
The protruding projecting chevron in side view is provided on each of the projecting parts with the guide.
It is provided so that the body contacts from the rear,
When the back support part tilts backward with respect to the guide body,
The contact portion of the guide body with respect to the convex portion is below the convex portion
From the top to the top
And further to the left of the central protrusion of the waist support.
By setting the protrusion height of the convex parts on both right side to be high,
When the back support part is tilted backward, from the central part of the waist support part
Also, the left and right sides are configured so that they project larger toward the front.
It is

In the present invention, the "waist" is a concept including the buttocks.

[0008]

[Operation and Effect of the Invention] With this configuration, when the back support is tilted backward, relatively forward protrudes as a whole lumbar support section for the back support portion and the waist support portion, left and right Both sides protrude forward more than the center. That is, when the back support portion is tilted backward, the waist support portion is deformed in a forward concave shape in a plan view.

On the other hand, since a person's waist (buttock) is gently curved backward convexly in a plan view, when a person leans against the backrest, the person's waist (buttock) is wrapped from behind by the waist support portion. It becomes like a state. In this way, a person's waist (buttock)
When the waist is wrapped in the waist support, the waist (buttock) support area of the waist support can be increased and the stability of the human posture can be improved. It is possible to significantly improve the quality.

Further, since each of the convex portions of the waist supporting portion has a mountain shape in a side view, the waist supporting portion largely protrudes in the initial stage of backward tilting of the back supporting portion, and the back supporting portion projects too much forward after tilting backward to some extent. Therefore, it is possible to prevent the waist support portion from protruding excessively forward. In this case, at the initial stage of the rearward tilt of the back support portion, the waist support portion is rapidly deformed into the shape of the frontward concave in a plan view, so that there is an advantage that the comfort in the rocking state can be further improved.

[0011]

Embodiments of the present invention will now be described with reference to the drawings. 1 to 22 show the first embodiment, and in these drawings, reference numeral 1 is a leg of a chair, reference numeral 2 is a seat receiving portion,
Reference numeral 3 indicates a seat body supported by the seat receiving portion 2, and reference numeral 4
Indicates a backrest with a cushion 6, respectively. Backrest 4
Is attached to the seat receiving portion 2 by a back support 16 formed in an L shape in a side view so as to be tiltable rearward.

The seat body 3 comprises a seat plate 3'made of synthetic resin and a cushion 5 mounted on the upper surface thereof. As shown in FIGS. 3 and 5 to 11, the seat receiving portion 2 includes a fixed frame body 7 fixed to the upper end of the leg body 1 and a movable seat receiving plate 8 arranged above the fixed frame body 7. . The movable seat receiving plate 8 is formed slightly narrower than the seat body 3.

The fixed frame body 7 is formed in a box shape having an upward opening, and its front portion is formed obliquely upward in a side view, and has the same width as the movable seat receiving plate 8 at the upper end of the front portion. A fixed seat receiving plate 9 having a size is fixed. On the lower surface of the movable seat receiving plate 8, hanging pieces 8a extending along both left and right side surfaces of the fixed frame body 7 are fixed, and the tip ends of these hanging pieces 8a are fixed to the left and right sides of the fixed frame body 7. The first bearing portion 10 formed on both side plates 7a is pivotally attached by a first pivot 11 extending in the left-right direction.

Sliders 13 are provided on both the left and right edges of the movable seat receiving plate 8 and the left and right edges of the fixed seat receiving plate 9, respectively.
And the seat body 3 is fixed to these sliders 13. Therefore, the seat body 3 is movable in the front-rear direction and can be tilted rearward, and the seat body 3 can be bent at the connecting portion between the front portion 3a and the rear portion 3b thereof. A mounting plate 18 extending along the side surface of the fixed frame body 7 is fixed to the front ends of the horizontal portions of the two back support rods 16. The upper and lower intermediate portions of the front portion of the mounting plate 18 are fixed to the fixed frame body. A second bearing portion 19 formed at a part of the side plate 7a of the rear plate 7 at a position slightly rearward of the first pivot 11 is pivotally attached by a second pivot 20 extending in the left-right direction.

A first support shaft 21 mounted between the lower ends of the mounting plates 18 of the left and right back support rods 16 is also provided.
And the second support shafts 22 mounted between the front end portions of the left and right side plates 7a of the fixed frame 7 are fitted with two left and right spring bearings 23, respectively. A coil spring 24 is mounted between the two 23 as an example of an elastic body that elastically supports the backrest 4.

In order that the mounting plate 18 of the back support 16 and the movable seat receiving plate 8 can be tilted rearward without interfering with each other, the projecting dimension of the second bearing portion 19 into which the second shaft pivot shaft 20 is fitted is set as follows. It is made larger than the projecting dimension of the first bearing portion 10 into which the first pivot 11 is fitted. The upper portions of the mounting plates 18 of the left and right back support members 16 project above the fixed frame member 7, and the third support shaft 25 is mounted between the front portions of the upper ends of the left and right mounting plates 18. On the other hand, an engaging member 26 having a pair of left and right side plates 26a is fixed to a portion of the lower surface of the seat body 3 above the third pivot 25, and a downward opening formed on both left and right sides 26a of the engaging member 26. The engaging groove hole 27 of is fitted into the third support shaft 25.

A guide groove 28 is formed in the upper part of the mounting plate 18 of the left and right back supports 16 and extends longitudinally in a rearward and rearward direction, and the movable seat receiving plate 8 is formed in each of the guide grooves 28. The end of the guide shaft 29 mounted between the left and right hanging pieces 8a is inserted. Relief holes 30 for allowing the rotation of the third support shaft 25 are formed in the left and right hanging pieces 8a of the movable seat receiving plate 8. In addition, the front end portion of the movable seat receiving plate 8 is notched to allow the rearward movement of the engaging member 26 (this notch is designated by reference numeral 3).
It shows with 1. (See FIGS. 3, 6 and 11).

Therefore, when the back support member 16 tilts backward, the seat member 3 is tilted rearward by the movable seat receiving plate 8, the pressing action of the third support shaft 25, and the guiding action of the guide slot 28.
It slides rearward while tilting rearward (however, the front portion 3a of the seat body 3 only slides rearward and does not tilt rearward). Next, the structure of the backrest 4 will be mainly described with reference to FIGS.
~ It demonstrates based on FIG.

The backrest 4 is formed in a hollow shape by fixing an outer shell 15 made of synthetic resin to an inner shell 14 made of synthetic resin having a cushion 6 mounted on the front surface thereof by an appropriate means such as screwing. The left and right side portions of the inner shell 14 are fixed to the upper end portion of the back support 16 by appropriate means such as screwing. Also, the backrest 4 is
Back support part 4a for supporting a person's back A (see FIG. 16)
And a narrow waist supporting portion 4b that supports a person's waist (buttock) B is vertically connected. The back support portion 4a of the backrest 4 is tilted backward at a gentle angle θ1 (about 100 degrees) with respect to the horizontal plane in a state where no load is applied (see FIG. 16).

On the other hand, the waist supporting portion 4b is formed by cutting two vertically elongated slits 4B downward to open a center member 4b 'located at the left and right central portions of the chair in a front view and side members 4b "located on both sides thereof. The inner shell 14 is formed in a plate shape, while the outer shell 15 is provided with an enclosing wall 15a at a portion excluding the lower end edge. In the outer shell 15 of the support portion 4b, a plurality of slits 17 extending between the left and right side edges are formed at appropriate vertical intervals so as to allow the deformation.

Therefore, the back support portion 4a of the backrest 4
Hardly elastically deforms, but the waist support portion 4b of the backrest 4 elastically deforms toward a state of linearly extending in a side view, and each member 4b 'of the waist support portion 4b,
4b ″ can be rotated in the front-rear direction about the root of the back support portion 4a. The groove width of each slit 17 in the outer shell 15 becomes wider toward the side edge of the surrounding wall 15a. Therefore, the outer shell 15 can be easily elastically deformed.
As shown in FIG. 2, when the outer shell 15 is stretched and deformed to some extent, the slits 17 are closed at the back surface of the outer shell 15, and the waist support portion 4b is not further deformed.

12 to 15 and 17 to 21.
The outer shell 15 is omitted. Angle-shaped projections 14a 'and 14a "protruding rearward in a side view are fixed to the back surfaces of the center member 4b' and the side members 4b" of the waist support portion 4b. The protrusion heights of the protrusions 14a ″ on both side members 4b ″ are set to be larger than the protrusion heights of the protrusions 14a ′ on the center member 4b ′. Each of the convex portions 14
a ', 14a "are the members 4 in the waist support 4b.
It is provided at a substantially central position on the left and right of b ', 4b ".

The protrusions 14a ', 14a "are made of an elastic material such as hard rubber. Therefore, the members 4b', 4b" of the waist support 4b are provided with the protrusions 14a ', 14a ". On the rear end surface of the fixed frame body 7, as an example of guide means, a guide body 35 made of a metal plate and extending substantially obliquely upward toward the inside of the hollow portion of the waist support portion 4b of the backrest 4 is provided. It is fixed.

By forming two slits 35A having upward openings in the guide body 35, the waist support portion 4 is formed.
The three rising portions 35 'and 35 "corresponding to the respective members 4b' and 4b" of b are formed. A pair of left and right brackets 35a are formed by bending left and right at the upper ends of the rising portions 35 ', 35 ".
A single support shaft 35c mounted on each bracket 35a is rotatably fitted with a pressing roller 35b that abuts each of the protrusions 14a ', 14a "of the waist support 4b.

A pair of left and right brackets 36 extending rearward are fixed to the lower ends of the members 4b ', 4b "of the waist supporting portion 4b, and the guide member 35 rises between the tips of the left and right brackets 36. A restriction roller 37 located at the back of the parts 35 ', 35 "is rotatably attached. The regulation roller 37 is an example of a spacing regulation means for preventing the members 4b ′, 4b ″ of the waist support portion 4b from being excessively separated from the guide body 35, and in a state before the backrest 4 tilts backward, There is a large gap between the regulation roller 37 of the side member 4b ″ and the rising portion 35 ″ of the guide body 35, and there is almost no gap between the regulation roller 37 of the center member 4b ′ and the rising portion 35 ′ of the guide body 35. It is set so that no gap is opened.

The pressing roller 35b of the guide body 35 and the respective convex portions 14a ', 14a "of the waist supporting portion 4b are related as follows: That is, as shown in FIG. When the pressure does not work, the pressing roller 35b
There positioned at the lower end portion of each convex portion 14a ', 14a ", 19
As shown in, when the backrest 4 tilts backward to a certain angle θ2 (about 110 degrees in the embodiment) with respect to the horizontal plane in a side view,
When the pressing roller 35b is located at the apex of the convex portions 14a ', 14a " and the backrest 4 is tilted backward to an angle .theta.3 (about 120 degrees in the embodiment) of the tilt limit , as shown in FIG.
The pressing roller 35b is associated so as to be located at the upper end of each convex portion 14a ', 14a ".

In the above structure, when a person sitting on a chair leans against the backrest 4, the backrest 4 tilts backward against the elasticity of the coil spring 24, as shown in FIGS. Then, the pressing roller 35b of the guide body 35
And the convex portions 14a ′, 14a ″ of the waist support portion 4b guide the respective portions 4b ′, 4b ″ of the waist support portion 4b to the back support portion 4a while stretching and deforming in the process of tilting backward. It projects relatively positively.

In this case, the waist support portion 4b has a convex portion 14a ',
Since 14a ″ is provided, in the initial stage of the backward tilting of the back support portion 4a, the forward pressing action of the waist support portion 4b by the guide body 35 exerts a large action to quickly project the back support portion 4a. After that, the forward pressing action of the waist support portion 4b by the guide body 35 does not work so much, and the relative postures of the back support portion 4a and the waist support portion 4b do not change much. It does not squeeze a person's waist B.

Further, since the height dimension of the convex portion 14a "of the side member 4b is larger than the height dimension of the convex portion 14a 'of the center member 4b' of the waist support portion 4b, both side members 4b" are backrests 4b '. Project more than. Therefore, as shown by the dotted line in FIG. 17, the waist (buttock) B of the person is wrapped in the waist support portion 4b in the initial stage of the rearward tilt of the back support portion 4a, and as a result, a comfortable rocking state is obtained. Can be done.

Since the distance between the regulating roller 37 and the guide body 35 on both side members 4b "is wide, both side members 4b" are initially formed at the initial stage of rearward tilting of the backrest 4.
Rotates so that its lower end protrudes significantly forward,
As a result, the side portion of the person's waist (buttock) B can be quickly supported (after the backrest 4 tilts backward to some extent and the regulation roller 37 contacts the guide body 35, both side members 4b ″ are placed on the side surface. It deforms so as to be visually extended and relatively projects with respect to the back support portion 4a).

On the other hand, the center member 4 of the waist supporting portion 4b
Since the regulating roller 37 is close to the guide body 35 from the beginning, the b ′ is tilted backward while deforming so as to be stretched in a side view from the beginning when the backrest 4 is tilted backward. As described above, the rear portion 3a of the seat body 3 is tilted rearward by the rotating action of the movable seat receiving plate 8, the pressing action of the third support shaft 25, and the guiding action of the guide groove hole 28. The front portion 3a of the seat body 3 slides rearward by the rearward tilting of the backrest 4 while interlocking with the rearward tilting and sliding backward.

As in this embodiment, when the seat body 3 is configured to bend in a side view and the front portion 3a of the seat body 3 is slid only backward, a person leans against the backrest 4. There is an advantage that the thigh portion can be prevented from being pushed up by the front portion of the seat body 3 in the hanging state. In the example, the backrest point (the point at which the upper half of the body hits the backrest first according to the JIS standard, the point P in FIGS. 1 and 22 in the example) and the sitting position standard point (the center point of the load on the seat) In the example, the distance between the backrest 4 and the point H in FIG. 1 and FIG. 22) is larger than the dimension L2 (see FIG. 1) when the backrest 4 is not tilted backward. Dimension L3 in the cut state (Fig. 2
2 )), and in the embodiment, L2 and L
The difference from 3 is set to about 4 mm.

Although the restricting roller 37 is provided on the back surface of the inner shell 14 of the backrest 4 in the above embodiment, the restricting roller 37 may be provided on the front surface of the lower end portion of the outer shell 15. In the above embodiment, the convex portions 14a ', 14a "are formed of an elastic body such as rubber, but as a means for forming the convex portions 14a', 14a", the applicant of the present application has previously filed a patent application. (Japanese Patent Application No. 5-245
As illustrated in have you 16 66 No.), a metal plate or hard synthetic resin plate curved form, which or fixed by screws or rivets, or integrally molded into hollow state ,
Alternatively, such as integrally molding the inner shell into a solid shape,
Various other structures can be adopted.

The guide body 35 is not limited to being formed in a plate shape and inserted into the waist support portion 4b, and various other modes can be adopted. Furthermore, the back support portion 4a and the waist support portion 4b of the backrest 4 do not have to be integrally molded of synthetic resin, and may be formed separately or connected. 23 to 25 show another embodiment of the present invention.

The second embodiment shown in FIG. 23 is a modification of the first embodiment, in which the pressing roller 35 is provided at each rising portion 3.
It is one that is not divided for every 5'and 35 ".
As another modification of the first embodiment, each pressing roller 3
The support shaft 35c of 5 may not be shared, and the support shaft 35c may be provided in a state of being divided for each rising portion 35 ', 35 ".

The third embodiment shown in FIG. 24 is also a modification of the first embodiment, in which the waist supporting portion 4b is formed so as to extend linearly in a plan view, and both side members 4 in the waist supporting portion 4b are formed.
In providing the convex portion 14a "on the b", the convex portion 14a "
Is provided in a state in which it is eccentric to a portion of the backrest 4 that is closer to the outer side. By doing this, both side members 4
When b ″ is pushed forward by the guide body 35, the left and right end portions of the side member 4b ″ greatly protrude, so that the waist support portion 4b should be deformed so as to be in close contact with a person's waist (buttock). You can

The fourth embodiment shown in FIG. 25 is the regulating roller 3
7 shows another example of the attachment means of the guide member 35.
In addition, a longitudinal slit 35B is formed corresponding to each member 4b ', 4b "of the waist support portion 4b, while the waist support portion 4b is formed.
A bracket 36 protruding rearward from the slit 35B is fixed to the lower end of each member 4b ′, 4b ″ in FIG. 1, and a regulation roller 37 is attached to this bracket 36 via a support shaft 37 ′.

[Brief description of drawings]

FIG. 1 is a right side view of a main part of a chair according to a first embodiment.

FIG. 2 is a rear view of the backrest.

FIG. 3 is an exploded perspective view of a main part.

FIG. 4 is an exploded perspective view of a backrest.

FIG. 5 is an enlarged side view of a main part.

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

7 is a sectional view taken along line VII-VII in FIG.

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

9 is a sectional view taken along line IX-IX of FIG.

FIG. 10 is a sectional view taken along line XX of FIGS. 6 and 9.

FIG. 11 is a partial perspective view of a seat receiving portion.

FIG. 12 is a rear view of the backrest with the outer shell omitted.

FIG. 13 is an enlarged view of a main part of FIG.

14 is a sectional view taken along line XIV-XIV of FIG.

15 is a sectional view taken along line XV-XV of FIG.

16 is a partial cross-sectional view taken along the line XVI-XVI of FIG.

FIG. 17 is a schematic plan view showing the relationship between a person's waist and the waist support.

FIG. 18 is a partial cross-sectional view taken along the line XVIII-XVIII of FIG. 13.

FIG. 19 shows a state in which the backrest is in the middle of rearward tilting, which is indicated by XVI- in FIG.
It is the figure seen at the XVI viewing location.

FIG. 20 shows a state in which the backrest is in the middle of rearward tilting, as shown in XVIII of FIG.
-XVIII is a view seen at a visual spot.

FIG. 21: XVI of FIG. 13 showing the backrest fully tilted backward
FIG. 6 is a diagram viewed from a position XVI.

22 is an overall view of FIG. 21. FIG.

FIG. 23 is a plan sectional view of an essential part of the second embodiment.

FIG. 24 is a plan view of an essential part of the third embodiment.

FIG. 25 is a view showing a fourth embodiment , in which (A) is a side sectional view of a main part.
FIG, (B) is a B-B Midan sectional view of (A).

[Explanation of symbols]

1 leg 2 seat receiving part 3 seat 4 backrest 4a back support 4b waist support 4b 'waist support center member 4b ″ Side member of waist support 7 Fixed frame 14 Inner shell 14a ', 14a "convex portion 15 Outer shell 24 coil spring 35 Guide body 35 ', 35 "rising part 35b pressing roller 37 Regulation Roller

Front page continued (72) Inventor Shunichi Takamatsu 1-4-12 Imafukuhigashi, Joto-ku, Osaka Ito-Kikurebio Co., Ltd. (72) Inventor Masaru Nakasako, Mitsuichi, Ueno, Kyoto Prefecture 28- 24 (56) References JP-A-2-63416 (JP, A) Actual development Sho 62-196047 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) A47C 3/026 A47C 7 / 14 A47C 7/44

Claims (2)

(57) [Claims] 1. A back which tilts backward while being elastically supported
A sauce,It consists of a back support part and a waist support part,Seat or seat
In the receiving part, tilt the back support part backwards to attach the waist support part.
A guy that projects forward relative to the back support
The body is provided so as to extend to the rear of the waist support portion.
A chair, Of the back surface of the waist support portion of the backrest, in front view
Sides that project backwards in the center and on the left and right sides
From the rear side, the guide body
It is provided so as to abut, The back support part tilts backward between the convex parts and the guide body.
When it moves, the contact point of the guide body with respect to the convex portion moves to the front.
Move from the lower part of the convex part to the upper part beyond the apex
Related, Furthermore, the left and right sides of the waist supporting portion are more than the central convex portion.
By setting the protrusion height of the convex portion of the side to be high,
Left side of the center of the waist support when the back support is tilted backward
Both sides on the right side are configured so that they project more toward the front.
The Chair with backrest. 2.The aboveWaist supportBecomes elastically deformed
Cage, this waist supportLocated in the center of the chair when viewed from the frontYou
RuLocated on the center member and its left and right sidesDoSidem
Separately formed into three parts withRameeNumber
To eachThe convex portions are provided one by oneon the other hand,On the upper end of the guide body, from the rear to the convex portion of the waist support
A pressing roller is provided, and the lower end of the waist support section is
There is a regulation roller that hits the back of the guide body. A chair with a backrest according to claim 1.