JP2018075110A - Load support member for chair, and chair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily form a three-dimensional load support surface while improving a flexibility in a shape of the load support surface of a load support member for chair, such as a backrest.SOLUTION: A backrest 6 includes a stretch material 65 and a back frame 60. The back frame 60 includes a pair of vertical rods 62 and a lower rod 64. The vertical rods 62 includes a projection 67 at a middle part between one end 62b and the other end 62a of the vertical rods, the projection 67 projecting in a direction intersecting with a surface of the stretch material 65. The lower rod 64 has a projected dimension at a center in a load apply direction to both ends such that a center part 63b projects rearwardly from both ends 63a, 63a of an upper rod 63. The lower rod 64 is formed to have rearwardly-convex corner parts between a linear part and an inclined part. The stretch material 65 is fixed at the lower rod 64 along the linear part, the inclined part, and the rearwardly-convex corner parts.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a chair load support member and a chair.

2. Description of the Related Art A chair having a backrest that stands up from the rear portion of a seating surface, the backrest including a net-like tension member and a back frame that holds the outer periphery of the tension member is known.
In such a backrest of a chair, the surface shape of the net-like tension material, that is, the shape of the load support surface of the backrest is determined by the shape of the back frame that holds the outer periphery of the tension material. For this reason, in the backrest using the net-like tension material, for example, it is difficult to dent a part of the load support surface backward, and the degree of freedom of the shape of the load support surface is low.

  On the other hand, for example, Patent Document 1 discloses a configuration in which a load supporting surface is formed by sewing a plurality of net-like tension members together. In this configuration, the load supporting surface has a three-dimensional shape by applying tension in the direction in which the seam portions are continuous by the seam portion that stitches the tension members together.

  Further, in Patent Document 2, the shape of the load support surface is three-dimensional by holding a part of the net-like tension material forming the load support surface so as to be pulled backward by the shape holding member provided on the back frame. A typical configuration is disclosed.

International Publication No. 2005-112704 JP 2011-24791 A

However, in the configuration disclosed in Patent Document 1, it is necessary to sew together a plurality of tension members, which takes time.
Moreover, in the structure disclosed by patent document 2, when assembling a backrest, a part of tension material must be fixed to the shape holding member provided in the back frame, and it takes an effort.
An object of the present invention made there is to increase the degree of freedom of the shape of the load support surface of the chair load support member such as a backrest, and to easily form a three-dimensional load support surface. It is to provide a member and a chair.

The present invention employs the following means in order to solve the above problems.
A load support member for a chair according to the present invention includes a tension member that forms a load support surface that receives a load of a seated person, and a frame member that supports an outer peripheral end of the tension member. The frame member extends in a first direction along the load support surface of the tension member, and a pair of first frame rods provided apart from each other in a second direction intersecting the first direction; A second frame rod that connects one end portions of the pair of first frame rods. The first frame rod is a protruding portion that protrudes toward the seated person in a third direction orthogonal to the load support surface at an intermediate portion between the one end portion and the other end portion of the first frame rod. have. The second frame rod is formed such that a central portion in the second direction protrudes on the opposite side of the seated person in the third direction with respect to both end portions in the second direction. The second frame rod is formed with a corner that protrudes on the opposite side of the seated person in the third direction between the center portion and the both end portions of the second frame rod. . The tension member is supported along the central portion, the both end portions, and the corner portion in the second frame rod.

  According to such a configuration, the tension along the second direction acts on the tension member at a portion located on the other end side of the first frame rod with respect to the protruding portion of the first frame rod. . Moreover, since the center part of the 2nd direction has protruded to the opposite side to the seated person in the 3rd direction with respect to the both ends of a 2nd direction, the tension | tensile_strength is 2nd frame It becomes the shape which became depressed toward the seated person side in the 3rd direction in the center part of this frame ridge. Furthermore, the upholstery is supported along the center, both ends, and corners in the second frame rod. Thereby, a load support surface becomes a three-dimensional shape.

  In the chair load support member according to the present invention, in the chair load support member, the second frame rod is formed at a central portion in the second direction and extends along the second direction. A straight portion and a slant that is formed continuously on both sides in the second direction with respect to the straight portion, and that inclines toward the seated person in the third direction toward the both ends. The row portion may be provided integrally.

  By comprising in this way, the tension | tensile_strength material can be made into the shape which was dented efficiently in the center part side of the 2nd frame collar.

  The tension member pulls the first portion fixed in a state where the tension along the second direction is applied between the pair of first frame rods and the second frame rod side. In a state in which tension is applied, the second portion fixed to the center portion in the second direction of the second frame rod, and the second frame rod, at both ends in the second direction A pair of fixed third portions.

  In this way, in the first part between the pair of first frame rods, tension is applied along the second direction, which is the direction in which the pair of first frame rods face each other, and the second direction The tension | tensile_strength of the direction pulled to the 2nd frame rod side was provided to the 2nd site | part fixed to the 2nd frame rod in the center part. With such a configuration, the load support surface formed by the tension member is the center of the load support surface in the second direction in the second part as compared with the case where the outer peripheral portion of the tension member is simply fixed to the frame member. The part is shaped to be recessed toward the seated person in the third direction. In this way, the load supporting surface can be made more three-dimensional.

  Moreover, the chair load supporting member according to the present invention is such that, in the chair load supporting member, the second portion is given higher tension than the first portion and the third portion. It may be.

  By comprising in this way, a tension | tensile_strength material is dented more largely in a 2nd site | part.

  The chair according to the present invention includes a leg portion installed on the floor, a seat supported by the leg portion, and a backrest comprising the chair load support member as described above, supported by the leg portion. .

  By comprising in this way, the 2nd frame collar side of the backrest load support surface formed with a tension material can be made into the hollow shape. In this way, the load supporting surface can be made more three-dimensional.

  According to the chair load support member and the chair according to the present invention, the degree of freedom of the shape of the load support surface of the chair load support member such as the backrest is increased, and the three-dimensional load support surface is easily formed. It becomes possible.

It is the perspective view which looked at the chair concerning one embodiment of this invention from diagonally forward. It is the perspective view which looked at the said chair from diagonally backward. It is the side view which looked at the said chair from the left. It is a perspective developed view which shows the structure of the backrest part of the said chair. It is a perspective view which shows the back frame which comprises the said backrest part. It is a plane sectional view which shows the structure of the lower collar of the said backrest part. It is a grid figure which shows the shape of the load support surface formed with the tension material of the said backrest part. It is a sectional side view of the center part of the left-right direction of the backrest part. It is a figure which shows the shape of the tension material in the state before mounting | wearing the said tension material to a back frame.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a chair load supporting member and a form for carrying out a chair according to the invention will be described with reference to the accompanying drawings. However, the present invention is not limited only to this embodiment.
In the following description, the direction facing the front of a person seated in a normal posture with the back facing the back of the chair will be referred to as `` front '', and the opposite direction will be referred to as `` rear '' . Also, the upward direction of a person seated in a chair in a normal posture is called “up”, the opposite direction is called “down”, and the left side of a person seated in the chair 1 in a normal posture is “left”, right Will be called "right".

  FIG. 1 is a perspective view of a chair according to an embodiment of the present invention as seen from diagonally forward. FIG. 2 is a perspective view of the chair as viewed obliquely from the rear. FIG. 3 is a side view of the chair as viewed from the left. FIG. 4 is a perspective developed view showing the configuration of the backrest of the chair. FIG. 5 is a perspective view showing a back frame constituting the backrest part. FIG. 6 is a cross-sectional plan view showing the configuration of the lower arm of the backrest. FIG. 7 is a grid diagram showing the shape of the load support surface formed by the tension member of the backrest. FIG. 8 is a side cross-sectional view of the center part in the left-right direction of the backrest part. FIG. 9 is a diagram showing the shape of the tension member in a state before the tension member is attached to the back frame.

  As shown in FIGS. 1 to 3, the chair 1 of this embodiment includes a leg portion 2 placed on the floor surface F, a box-like support base 3 installed at the upper end of the leg portion 2, and a seating. A seat 4 on which a person sits, a seat receiving member 5 that is attached to the upper surface of the support base 3 and supports the seat 4, and a back of a seated person that extends from the support base 3 to the rear upper side and is seated on the seat 4 And a backrest portion 6 that supports

  The leg 2 includes a multi-leg 7 with casters 7a and a pedestal column 8 that stands up from the center of the multi-leg 7 and incorporates a gas spring as a lifting mechanism.

  The support base 3 is attached to the upper end portion of the pedestal column 8 so as to be rotatable in the horizontal direction. The support base 3 incorporates an elevation adjustment mechanism for the pedestal column 8 and a tilt adjustment mechanism for the backrest 6.

  The seat body 4 includes a base plate 13 that forms a skeleton, a cushion material 14 made of urethane or the like attached to the top of the base plate 13, and a tension member 15 that covers the outer peripheral surface of the base plate 13 from the outer surface of the cushion material 14. And.

  The substrate 13 is made of a synthetic resin having elasticity, and has a substantially rectangular shape with rounded four corners when viewed from above. The substrate 13 is held by a seat receiving member 5 fixed on the support base 3 so as to be slidable back and forth.

  The backrest 6 supports the load from the back of the seated person who is seated on the seat body 4. The backrest 6 includes a back frame (frame material) 60 and a tension member 65 stretched on the back frame 60. The front surface of the tension member 65 is a load support surface 65f that receives the load of the seated person.

  The back frame 60 has a base portion 61 connected to a tilt adjustment mechanism in the support base 3. The support base 3 is provided with an operation knob 12. By operating the operation knob 12, a reaction force when the back frame is tilted in the front-rear direction can be adjusted.

  As shown in FIGS. 1 to 5, the back frame 60 includes a pair of vertical rods (first frame rods) 62, an upper rod 63, and a lower rod (second frame rod) 64. . The vertical rod 62, the upper rod 63, and the lower rod 64 are continuously formed in an annular shape by, for example, resin, aluminum alloy or the like.

  The pair of vertical rods 62 extend in the vertical direction along the load support surface 65f of the tension member 65, and are spaced apart in the horizontal direction. The vertical rod 62 is opposite to the load input direction P (see FIG. 3) to the load support surface 65f of the upholstery material 65 at an intermediate portion between the upper end portion (other end portion) 62a and the lower end portion (one end portion) 62b. It has a protruding portion 67 that protrudes forward on the side (the occupant side in the third direction orthogonal to the load support surface).

  The upper collar 63 extends in the left-right direction, and connects the upper ends 62 a of the pair of vertical collars 62. In the upper collar 63, the central portion 63b in the left-right direction protrudes backward (in the third direction opposite to the seated person), which is the load input direction P, with respect to the left and right ends 63a, 63a. It is formed to do.

  The lower rod 64 is provided to be separated from the upper rod 63 in the vertical direction, and connects the lower ends 62b of the pair of vertical rods 62 to each other. The lower collar 64 is formed such that the central portion 64b in the left-right direction protrudes rearward in the load input direction P with respect to the load support surface 65f with respect to the left and right end portions 64a, 64a.

Here, as shown in FIG. 6, the lower collar 64 has a straight portion 64p and a skew portion 64s on the side where the tension member 65 is stretched, facing forward. The linear portion 64p is formed in the central portion 64b in the left-right direction of the lower collar 64, and extends along the left-right direction. The oblique portion 64s is formed continuously on both sides in the left-right direction with respect to the linear portion 64p. The skewed portions 64s and 64s are formed so as to incline forward in a direction opposite to the load input direction P from both ends of the linear portion 64p toward both ends 64a and 64a on the outer side in the left-right direction. ing. Further, the lower collar 64 is formed with a corner 64t that protrudes rearward (opposite to the seated person in the third direction) between the linear part 64p and the skew part 64s.
In such a lower collar 64, with respect to both end portions 64a and 64a, the rearward projecting dimension S1 of the linear portion 64p of the central portion 64b has a rearward direction of the central portion 63b with respect to both end portions 63a and 63a of the upper collar 63. It is formed to be larger than the protruding dimension S2 (see FIG. 3).

  A groove 66 that is recessed toward the inside of the backrest 6 is formed continuously in the circumferential direction on the outer peripheral edge of the pair of vertical collars 62 and 62 and the upper collar 63 of the back frame 60. .

  The tension member 65 has a mesh shape in which a large number of holes are formed, and an outer peripheral end portion 65e of the tension member 65 is wound into grooves 66 and 66m (see FIG. 8) formed in the back frame 60 and fixed by the edge member 68. ing.

As shown in FIGS. 1 and 7, the tension member 65 includes a first part A1, an upper collar fixing part A2, a second part A3, and third parts A4 and A4.
The first portion A1 of the tension member 65 is fixed between the pair of vertical rods 62 and 62 in a state where a tension T1 along the left-right direction is applied.
As shown in FIGS. 1 and 8, the upper collar fixing portion A2 of the tension member 65 is fixed to the upper collar 63 above the first portion A1.
The second portion A3 of the tension member 65 is fixed in a state in which a tension T2 is applied to pull toward the linear portion 64p formed in the central portion 64b of the lower collar 64 in the left-right direction. Here, it is preferable that the second part A3 is given higher tension than the first part A1 and the third part A4.
The third portions A4, A4 of the tension member 65 are formed on both sides of the second portion A3 in the left-right direction, and on the skewed portions 64s, 64s formed on the left and right ends 64a, 64a of the lower collar 64, In particular, it is fixed without applying tension.

Here, the 2nd site | part A3 is being fixed in the state pulled with respect to the linear part 64p of the lower collar 64 in the direction of the lower collar 64 strongly. In this embodiment, as shown in FIG. 6, the second part A3 is fixed over the entire length between both ends of the linear part 64p of the lower collar 64.
Further, the tension member 65 is fixed along the straight portion 64p, the skew portions 64s and 64s, and the corner portions 64t and 64t on both sides in the left-right direction of the straight portion 64p in the lower collar 64. . Specifically, as shown in FIG. 8, the lower collar 64 is provided with a fixing member 69 along the front surface thereof. The fixing member 69 includes a base portion 69a that is fixed to a recess 64u formed on the front surface of the lower collar 64, and an extending portion 69b that extends downward with a space in the front-rear direction between the front surface of the lower collar 64, It has. The tension member 65 is wound around a downward groove 66m formed between the front surface of the lower collar 64 and the extending portion 69b of the fixing member 69, and is fixed by an edge member 68 (see FIG. 4).

  By comprising in this way, the tension | tensile_strength T1 along the left-right direction acts on 1st site | part A1 which is the area | region of the upper collar 63 side rather than the protrusion part 67 of the vertical collar 62. FIG. The tension T1 in the left-right direction applied to the tension member 65 acts so as to connect the protruding portions 67 of the pair of vertical rods 62 linearly. As described above, by providing the protruding portion 67 on the vertical rod 62, the tension T1 along the left-right direction is less likely to act on the lower rod 64 side than the protruding portion 67 of the vertical rod 62.

On the other hand, as shown in FIG. 8, the second portion A3 formed in the region closer to the lower collar 64 than the protrusion 67 of the vertical collar 62 has the tension member 65 as a linear portion 64p of the lower collar 64. By pulling in the direction, a tension T2 including a component Td facing downward and a component Tp in the load input direction P is applied. As shown in FIG. 1, the tension T <b> 2 is a straight line between the straight portion 64 p (see FIG. 6) at the center in the left-right direction of the lower rod 64 and the protrusions 67 of the pair of vertical rods 62. It acts on the substantially trapezoidal region D that is connected in a concentrated manner. Therefore, in the second portion A3, the load support surface 65f of the tension member 65 is recessed backward.
Furthermore, by fixing the tension member 65 with at least two corners 64t and 64t at both ends of the linear portion 64p of the lower collar 64, the tension member 65 is attached to the linear portion 64p from both left and right ends. A ridge line L extending so as to gradually expand toward the protrusions 67, 67 of the upper vertical rod 62 is formed. Here, the tension of the tension member 65 is not applied to the third portion A4, and the tension T1 in the left-right direction is not applied to the lower part of the tension member 65. As a result, the second part A3 and the third part A4 are less likely to lift from the lower collar 64 at the lower part of the tension member 65. Therefore, the dent in the second portion A3 becomes visually more noticeable.

In order to assemble the backrest portion 6 as described above, first, the first portion A1 of the tension member 65 is fixed in a state where a tension T1 is applied along the left-right direction between the pair of vertical saddles 62. At the same time, the upper collar fixing portion A2 is fixed to the upper collar 63.
Next, the second portion A3 is fixed to the linear portion 64p of the lower collar 64 in a state where a tension T2 that is pulled toward the lower collar 64 is applied to the central portion in the left-right direction of the tension member 65.
Thereafter, the tension member 65 is fixed to the skewed portions 64 s and 64 s on both sides in the left and right direction of the lower collar 64, respectively, and the pair of third portions A4 are fixed.
By comprising in this way, the backrest part 6 as mentioned above can be assembled.

  By the way, as shown in FIG. 9, the upholstery material 65 constituting the backrest portion 6 has a shape that conforms to the outer shape of the back frame 60 as a whole without being stretched on the back frame 60. That is, the tension member 65 includes first peripheral edge portions 65a and 65a fixed to the pair of vertical rods 62 in a state where a tension T1 along the left-right direction is applied between the pair of vertical rods 62, and the upper rods. An upper edge 65b fixed to 63 and a second peripheral edge 65c fixed to the linear portion 64p at the center in the left-right direction of the lower collar 64 in a state where a tension T2 is applied to the lower collar 64. And a pair of third peripheral edge portions 65d and 65d fixed to the skewed portions 64s and 64s at both ends in the left and right direction in the lower collar 64.

Here, the second peripheral edge portion 65c is formed with a belt-like portion 65x protruding downward from the third peripheral edge portions 65d and 65d on both sides in the left-right direction. When the tension member 65 is attached to the back frame 60 by the assembling method of the backrest portion 6 as described above, the second peripheral edge portion 65c is lowered with the tension T2 applied by pulling the belt-like portion 65x downward. It fixes to 64 linear part 64p.
In addition, the root portions 65n and 65n on both sides in the left-right direction of the belt-like portion 65x are concave upward. Thereby, when the tension T2 is applied to the belt-like portion 65x, the tension T2 is difficult to reach the third peripheral portions 65d and 65d (third portions A4 and A4) on both sides in the left-right direction.
Furthermore, the third peripheral edge portions 65d and 65d are formed in a curved shape that protrudes downward. While the second peripheral portion 65c is strongly pulled downward and fixed to the lower collar 64, the third peripheral portions 65d and 65d are not pulled strongly, and the grooves 66 of the inclined portions 64s and 64s of the lower collar 64 are provided. The third portion A4 is prevented from generating a tension by being caught in the wire.

As described above, the vertical rod 62 has the protruding portion 67 that protrudes forward in the opposite direction to the load input direction P at the intermediate portion between the upper end portion 62a and the lower end portion 62b. With this configuration, the tension T1 along the left-right direction acts on the first portion A1 on the upper collar 63 side of the protruding portion 67 of the vertical rod 62, whereas the tensile force T1 acts on the first portion A1. The tension T1 along the left-right direction is less likely to act on the lower eyelid 64 side. Thus, by providing the protrusion 67 on the vertical rod 62, a region where the tension T1 along the left-right direction acts can be clearly formed.
Further, the lower collar 64 is formed such that the central portion 64b protrudes rearward with respect to both end portions 64a and 64a. Further, the lower collar 64 is formed with a corner 64t that protrudes rearward (opposite to the seated person in the third direction) between the linear portion 64p and the skewed portion 64s. The tension member 65 is fixed on the lower collar 64 along the straight portion 64p, the skewed portions 64s and 64s, and the corner portions 64t and 64t on both sides in the left-right direction of the straight portion 64p. Thereby, tension | tensile_strength T2 is provided to 2nd site | part A3, and 2nd site | part A3 of the upholstery material 65 becomes a shape dented back.

  The lower collar 64 is integrally provided with a linear portion 64p and skew portions 64s and 64s formed continuously on both sides in the left-right direction with respect to the linear portion 64p. By comprising in this way, 2nd site | part A3 of the upholstery material 65 can be made into the shape dented back efficiently.

  Further, the lateral tension T1 applied to the tension member 65 acts so as to tie the protruding portions 67 of the pair of vertical rods 62 in a straight line. On the other hand, in the second region A3, the tension T2 applied to the tension member 65 is a trapezoidal region D that connects the linear portion 64p of the lower collar 64 and the protrusions 67 of the pair of vertical collars 62 to each other. Acts intensively. Therefore, the load supporting surface 65f of the tension member 65 is effectively recessed at the second portion A3 located in the region connecting the lower rod 64 and the protruding portions 67 of the pair of vertical rods 62.

Further, in the first portion A1 between the pair of vertical rods 62, a tension T1 is applied to the tension member 65 along the left-right direction, which is the direction in which the pair of vertical rods 62 face each other. A tension T2 that is pulled to the lower eyelid 64 side was applied to the second portion A3 fixed to the lower eyelid 64. With such a configuration, the load support surface 65f formed by the tension member 65 is compared with a case where the outer peripheral portion of the tension member 65 is simply fixed to the back frame 60. The central part of the direction is recessed backward. In this way, the load support surface 65f can be formed into a more three-dimensional shape. In addition, since the tension member 65 may be fixed to the back frame 60 while sequentially applying the tensions T1 and T2, the assembling work of the backrest portion 6 can be easily performed.
Further, by applying a tension T2 that pulls toward the lower eyelid 64 to the second part A3, the load support surface 65f has a shape in which the central portion in the left-right direction is recessed rearward, so that the load support surface 65f is used by the user. The shape is excellent in the holdability of the back.
Thereby, the freedom degree of the shape of the load support surface 65f of the backrest part 6 can be increased, and a three-dimensional load support surface can be easily formed.

  In addition, the second portion A3 was given higher tension than the first portion A1 and the second portion A3. By comprising in this way, the tension | tensile_strength material 65 is dented more largely in 2nd site | part A3.

  Moreover, in the 2nd site | part A3 of the tension | tensile_strength material 65, it fixes by the 2 or more points spaced apart in the left-right direction with respect to the lower collar 64, and is pulled to the lower collar 64 side given to 2nd site | part A3. The tension T2 clearly acts linearly from the point where the tension member 65 is fixed to the lower rod 64 toward the upper rod 63 side. As a result, the ridge line L can be formed in the upholstery material 65, and the depression in the second portion A3 becomes visually more noticeable.

(Other embodiments)
In addition, this invention is not limited to said embodiment, A various design change is possible in the range which does not deviate from the summary. For example, although the above-described embodiment is an embodiment in which the load support is a backrest, a similar structure can be adopted for the seat.
For example, the lower collar 64 is integrally provided with a linear portion 64p and skew portions 64s and 64s formed continuously on both sides in the left-right direction with respect to the linear portion 64p. Not exclusively. For example, any one of the linear part 64p and the skew part 64s of the lower collar 64 may be curved so as to protrude toward the opposite side of the seated person in the third direction. Also, the lower eyelid 64 has a curved shape that protrudes toward the opposite side of the seated person in the third direction, and has a central portion in the second direction and both end portions in the second direction with respect to the central portion. Alternatively, the curvature of the curved shape may be varied.
Further, in order to fix the tension member 65 along the linear portion 64p of the lower collar 64, the oblique portions 64s and 64s, and the corner portions 64t and 64t on both sides in the left-right direction of the linear portion 64p, the tension member is used. 65 may be wound around the groove 66 and fixed by the edge material 68, or may be fixed by a holding member pressed from the front, or may be fixed by a tucker or the like.
In addition, for example, the tension member 65 acts on the second portion A3 due to the difference in the position in the vertical direction (first direction) between the second peripheral portion 65c and the third peripheral portions 65d and 65d. As long as the applied tension T2 does not reach the third portions A4 and A4, any shape may be used. For example, the third peripheral edge portions 65d and 65d may protrude greatly below the second peripheral edge portion 65c, and the second peripheral edge portion 65c protrudes below the third peripheral edge portions 65d and 65d. You may do it.
Further, the second portion A3 is formed by fixing the second peripheral edge portion 65c of the tension member 65 over the entire length between both ends of the linear portion 64p of the lower collar 64, but the ridge line L is formed. If it can do, the 2nd site | part A3 should just be fixed with respect to the lower eyelid 64 by two or more points spaced apart in the left-right direction.
In the above embodiment, the tension member 65 is fixed to the upper collar 63, but the tension material 65 may not be fixed to the upper collar 63.
Further, the back frame 60 may be configured not to include the upper collar 63 but to include only the pair of vertical collars 62 and 62 and the lower collar 64.

1 Chair 2 Leg 4 Seat 6 Backrest 60 Back frame (frame material)
62 Downspout (first frame)
62a Upper end (other end)
62b Lower end (one end)
63 Upper rod 63a End 63b Central portion 64 Lower rod (second frame rod)
64a End portion 64b Central portion 64p Straight portion 64s Skew portion 64t Corner portion 65 Upholstery material 65e Outer peripheral end portion 65f Load support surface 67 Projection portion A1 First portion A2 Upper collar fixing portion A3 Second portion A4 Third portion Part D Region F Floor L Edge P Load input direction S1, S2 Protrusion dimension T1 Left-right tension T2 Tensile tension

Claims (5)

A upholstery that forms a load bearing surface that receives the load of the seated person;
A frame member that supports the outer peripheral end of the tension member;
With
The frame material is
A pair of first frame rods extending in a first direction along the load support surface of the tension member and spaced apart in a second direction intersecting the first direction;
A second frame rod connecting one ends of the pair of first frame rods;
With
The first frame rod is a protruding portion that protrudes toward the seated person in a third direction orthogonal to the load support surface at an intermediate portion between the one end portion and the other end portion of the first frame rod. Have
The second frame rod is formed so that the central portion of the second direction protrudes to the opposite side of the seated person in the third direction with respect to both ends of the second direction,
Between the central portion and the both end portions of the second frame rod, corner portions that are convex on the opposite side to the seated person in the third direction are formed, respectively, and A load supporting member for a chair, which is supported along the central portion, the both end portions, and the corner portion in a frame. The second frame rod is
A linear portion formed in the center of the second direction and extending along the second direction;
A skewed portion that is formed continuously on both sides in the second direction with respect to the linear portion, and that inclines toward the seated person in the third direction toward the both end portions and extends linearly. The load supporting member for a chair according to claim 1, which is provided integrally. The upholstery is
A first portion fixed in a state in which a tension along the second direction is applied between the pair of first frame rods;
A second portion fixed to a central portion of the second frame rod in the second direction with a tension applied to the second frame rod side; and
In the second frame rod, a pair of third parts fixed to both ends in the second direction;
The load supporting member for chairs of Claim 1 or 2 provided with these.   The load supporting member for a chair according to claim 3, wherein the second portion is provided with a higher tension than the first portion and the third portion. Legs installed on the floor,
A seat supported by the legs;
A backrest comprising the load supporting member for a chair according to any one of claims 1 to 4, supported by the leg portion,
A chair equipped with.

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