JP7740959B2 - Chair load support member and chair - Google Patents

Description

The present invention relates to a load-supporting member for a chair and a chair.

Patent Document 1 discloses a chair comprising a front crossbeam, a seat crossbeam, a back crossbeam, back webbing, and seat webbing. The seat webbing is stretched between the front crossbeam and the seat crossbeam. The back webbing is stretched between the back crossbeam and the seat crossbeam. One end edge of the back webbing and one end edge of the seat webbing are attached to the seat crossbeam by a hook.

Japanese Utility Model Publication No. 55-52854

In the aforementioned chair, the attachment structure between the webbing (upholstery) and the seat beam (rod) did not look very appealing. Therefore, improvements were needed in terms of appearance.

One aspect of the present invention aims to provide a load-supporting member for a chair and a chair that have a good appearance in a structure in which a tensioning material is stretched over a rod.

One aspect of the present invention provides a load-supporting member for a chair, comprising a pair of spaced-apart first rods, an upholstery stretched between the pair of first rods and having a load-receiving surface that receives the weight of a seated occupant, a second rod spanning the pair of first rods and to which the upholstery is attached, and a cover that covers the attachment portion where the upholstery is attached to the second rod.

In this embodiment, the attachment portion of the upholstery material is covered with the cover, making it difficult to see from the outside. As a result, the attachment portion does not detract from the appearance of the chair. This results in a chair with a good appearance.

The attachment portion is preferably a holding portion formed by folding the upholstery material into a loop shape around the second rod.
According to this aspect, the structure of the mounting portion is simple, and therefore the mounting portion can be easily manufactured.

The cover body preferably has a recess formed therein for accommodating at least a portion of the second rod.
According to this aspect, the attachment portion can be made less visible from the outside.

The second rod preferably engages with the recess.
According to this aspect, the displacement of the second rod can be restricted, making it easy to position the second rod and the cover body.

The second rod is preferably elastically deformable.
According to this aspect, when the cover body has a curved shape, the second rod has a shape corresponding to the curved shape of the cover body, which makes it easy to position the second rod relative to the cover body.
According to this aspect, the second rod is flexibly deformed in response to the seating load input to the upholstery material, thereby providing a flexible seating feel.

The first rod comprises side rods that form the seat frame, which is the outer shell of the seat, and vertical rods that form the back frame, which is the outer shell of the backrest; the upholstery is stretched between the pair of side rods, the side rods and the vertical rods are connected at a connecting portion; the back frame has an upper rod that connects the upper ends of the pair of vertical rods; and the second rod is separate from the first rod and is preferably located on the vertical rods closer to the connecting portion than the upper rod.

In this embodiment, the second rod is located close to the connecting portion, making it difficult to form it integrally with the first rod. However, because the second rod is separate from the first rod, it does not need to be molded integrally with the first rod. This means that the structure of the manufacturing mold does not become complicated, thereby reducing manufacturing costs.

Another aspect of the present invention provides a chair comprising the chair load-bearing member and a support structure supporting the chair load-bearing member.
According to this aspect, the attachment portion of the upholstery material is covered with the cover body, so that a chair with a good appearance can be obtained.

One aspect of the present invention provides a chair load support member and chair that have a good appearance in a structure in which a tensioning material is stretched over a rod.

FIG. 1 is a side view of a chair according to an embodiment. FIG. 1 is a perspective view of a chair in a partially cross-sectional state according to an embodiment. FIG. 2 is a perspective view of the chair body and the support base in the embodiment. FIG. 2 is a perspective view of a chair body in a partially cross-sectional state according to the embodiment. FIG. 2 is an exploded perspective view of a chair body in a partially cross-sectional state according to the embodiment. FIG. 2 is an exploded perspective view showing an enlarged portion of the chair according to the embodiment. 3 is a cross-sectional view of a first connecting frame and a second connecting frame in the embodiment, taken along the length direction. FIG. 3 is a cross-sectional view of a first connecting frame and a second connecting frame in an embodiment, taken perpendicular to the length direction. FIG. FIG. 1 is a perspective view of a portion of a chair according to an embodiment. FIG. 2 is a perspective view showing a cross section of a first connecting frame and a second connecting frame of the chair in the embodiment. FIG. 2 is a perspective view showing a cross section of a first connecting frame and a second connecting frame of the chair in the embodiment. FIG. 2 is a perspective view showing a cross section of a first connecting frame and a second connecting frame of the chair in the embodiment.

Next, embodiments of the present disclosure will be described with reference to the drawings. In the embodiments and variations described below, corresponding components may be designated by the same reference numerals and their description may be omitted. In the following description, expressions indicating relative or absolute arrangements, such as "parallel," "orthogonal," "center," and "coaxial," not only refer to such arrangements in a strict sense, but also to relative displacements with tolerances or angles or distances that provide the same functionality.

Fig. 1 is a side view of the chair 1. Fig. 2 is a perspective view of the chair 1 in a partially cross-sectional state.
As shown in FIGS. 1 and 2, the chair 1 comprises a support structure 2, a chair body 3, and armrests 4.

In the following description, directions such as front-to-back, up-down, left-to-right, etc. are defined based on a person (occupant) seated in the correct posture on chair 1. In the diagram, the arrow UP indicates upward. The arrow FR indicates forward. The arrow RH indicates right. On chair 1, the side away from the center in the front-to-back and left-to-right directions is sometimes referred to as the outside, and the side toward the center is sometimes referred to as the inside. The left-to-right direction is the width direction of chair 1. A plan view refers to a view from the top-to-bottom direction. A side view refers to a view from the left-to-right direction.

<Support structure 2>
As shown in FIG. 1 , the support structure 2 includes legs 11 and a support base 12 .
The leg 11 includes a multi-leg 14 and a pedestal 15. Each leg of the multi-leg 14 is fitted with a caster 16 that can run on a floor surface F. The leg 11 is placed on the floor surface F.

The leg pillar 15 is erected at the center of the multi-legged leg 14. The leg pillar 15 houses a gas spring 17, which is the lifting mechanism for the chair 1. The gas spring 17 is configured such that, for example, the inner cylinder 17a is supported so that it can be raised and lowered and rotated relative to the chair.

3 is a perspective view of the chair body 3 and the support base 12. In FIG. 3, the upholstery materials 111 and 112 are omitted.
As shown in Fig. 1, the support base 12 is fixed to the upper end of the pillar 15 (inner cylinder 17a). As shown in Fig. 3, the support base 12 includes a casing 21, a lifting operation mechanism 22, a tilting mechanism 23, and a tilt adjustment mechanism 24.

The casing 21 is formed in a box shape and includes a case body 31, a pair of forward extending portions 32, and a rear case 33.
The pair of forward extending portions 32 extend obliquely forward from both left and right end portions of the case body 31. The rear case 33 protrudes rearward from the center of the case body 31 in the left and right direction.

The lifting operation mechanism 22 includes an operating rod 142. The operating rod 142 protrudes from the case body 31. The lifting operation mechanism 22 can operate the gas spring 17 by using the operating rod 142.
The tilting mechanism 23 includes a backrest support shaft (not shown). The backrest support shaft is a shaft member that passes through the rear case 33 in the left-right direction.
The tilt adjustment mechanism 24 includes an operating rod 62. The tilt adjustment mechanism 24 can adjust the ease with which the backrest 101 can rotate by operating the operating rod 62.

<Chair body 3>
As shown in FIGS. 1 and 2, the chair body 3 includes a seat 100 and a backrest 101.
The seat 100 extends in the front-to-rear direction in a side view. A portion of the seat 100 is inclined downward toward the front. The upper surface of the seat 100 forms a seat surface 100a that supports the area from the buttocks to the thighs of the seated occupant from below. The seat surface 100a is a load-receiving surface that receives the weight of the seated occupant. The seat 100 is supported on the support base 12 so that it can slide in the front-to-rear direction.

The backrest 101 extends generally upward from the rear end of the seat 100. In this embodiment, the backrest 101 has a gentle S- or Z-shape in side view. The front surface of the backrest 101 forms a back support surface 101a that supports the lumbar and back of the seated occupant from behind. The back support surface 101a is a load-bearing surface that receives the weight of the seated occupant.

The backrest 101 is rotatable about an axis O1 that runs left-right relative to the seat 100. The backrest 101 is connected to the support base 12 so as to be rotatable about an axis O2 of the backrest support shaft of the tilting mechanism 23. The seat 100 can slide forward and backward relative to the support base 12 as the backrest 101 rotates about axis O2 relative to the support base 12 and as the backrest 101 rotates about axis O1 relative to the seat 100.

The specific configuration of the chair body 3 will be described below.
The chair body 3 includes a shell 110, a first upholstery material 111 (seat upholstery material), and a second upholstery material 112 (backrest upholstery material).
The shell 110 is a frame-shaped member that forms the outer shell of the chair body 3. The shell 110 includes a seat frame 120 and a back frame 123.

The seat frame 120 forms the outer shell of the seat 100. The back frame 123 forms the outer shell of the backrest 101. The seat frame 120 and back frame 123 are molded from, for example, a resin material. The chair body 3 is an example of a "chair load support member."

As shown in Figure 3, the seat frame 120 is U-shaped and opens rearward in a plan view. Specifically, the seat frame 120 includes a front rod portion 130 and a pair of side rod portions 131.

The front rod 130 extends in the left-right direction at the front end of the seat 100.
The pair of side rods 131 extend rearward from both ends of the front rod 130. The pair of side rods 131 are arranged spaced apart in the left-right direction.

The back frame 123 includes a main frame 151 and a support frame 152 .
The main body frame 151 is formed in a rectangular frame shape when viewed from the front, and includes a pair of vertical rods 155, an upper rod 157, a first connecting frame 158 (see FIG. 4 ), and a second connecting frame 159.

The pair of vertical rods 155 are spaced apart in the left-right direction. Each vertical rod 155 includes a lower frame 150 and a main rod 153.
The front end of the lower frame 150 is rotatably connected to the rear end of the side rod portion 131. The location where the side rod portion 131 and the lower frame 150 are connected is referred to as the "connecting portion 122." In other words, the side rod portion 131 and the vertical rod portion 155 (more specifically, the lower frame 150) are connected at the connecting portion 122 so as to be rotatable around the axis O1.

The lower frame 150 is inclined upward toward the rear. A holding recess 154 (see Figure 5) is formed on the inner surface (inner surface in the left-right direction) of the rear end of the lower frame 150.

The main rod portion 153 extends upward from the rear end of the lower frame 150. Specifically, the main rod portion 153 comprises a first portion 153a and a second portion 153b. The first portion 153a extends from the rear end of the lower frame 150 at an angle, advancing upward. The second portion 153b extends from the upper end of the first portion 153a at an angle, advancing backward as it extends upward.

The side rods 131 of the seat frame 120 and the vertical rods 155 of the back frame 123 form the first rods 124. The pair of first rods 124 are arranged spaced apart in the left-right direction. The pair of first rods 124 are arranged side by side facing each other in the left-right direction.

The upper rod portion 157 extends in the left-right direction. The upper rod portion 157 spans the upper ends of the pair of vertical rod portions 155. The upper rod portion 157 connects the upper ends of the pair of vertical rod portions 155 together.

Fig. 4 is a perspective view of the chair body 3 in a partially cutaway state. Fig. 5 is an exploded perspective view of the chair body 3 in a partially cutaway state.
As shown in Figures 4 and 5, the first connecting frame 158 is a rod extending in the left-right direction. A cross section of the first connecting frame 158 perpendicular to the longitudinal direction is, for example, circular. The first connecting frame 158 is made of, for example, metal. The first connecting frame 158 spans the rear ends of the pair of lower frames 150. The first connecting frame 158 connects the rear ends of the pair of lower frames 150 together. The first connecting frame 158 is a separate body from the first rod 124. The first connecting frame 158 is an example of a "second rod."

The first connecting frame 158 is elastically flexible and has bending characteristics such that, for example, when a force is applied to the first connecting frame 158 in a bending direction, the bending deformation can be visually confirmed.
The first connecting frame 158 is provided at a position closer to the connecting portion 122 than the upper rod portion 157 (see FIG. 3).

As shown in FIG. 5, both ends of the first connecting frame 158 are connected to the vertical rod portions 155 via holders 40. That is, one end of the first connecting frame 158 is connected to one vertical rod portion 155 via a first holder 40. The other end of the first connecting frame 158 is connected to the other vertical rod portion 155 via a second holder 40.

Fig. 6 is an enlarged exploded perspective view of a portion of the chair 1. Fig. 7 is a cross-sectional view of the first connecting frame 158 and the second connecting frame 159 along the length direction.
As shown in Figures 6 and 7, the holder 40 includes a holder body 41, a fastener 42 (bolt), and a receiving device 43 (nut). The holder body 41 is formed in a block shape. The holder body 41 has a first insertion hole 41a, a second insertion hole 41b, and a third insertion hole 41c. As shown in Figure 7, the holder body 41 is formed with a fitting recess 41d that holds the receiving device 43. The holder 40 fits into the holding recess 154 of the vertical rod portion 155.

As shown in Figures 6 and 7, the end of the first connecting frame 158 is inserted into the first insertion hole 41a of the holder 40.

As shown in FIGS. 4 and 5 , the second connecting frame 159 includes a rod portion 171 and a cover body 172 .
The second connecting frame 159 is bridged across the pair of vertical rods 155 (see FIG. 3). More specifically, the second connecting frame 159 is bridged across the rear ends of the pair of lower frames 150. The second connecting frame 159 connects the rear ends of the pair of lower frames 150 together.

The rod portion 171 is a rod body extending in the left-right direction. A cross section perpendicular to the longitudinal direction of the rod portion 171 is, for example, circular. The rod portion 171 is made of, for example, metal. The rod portion 171 spans the pair of vertical rod portions 155. More specifically, the rod portion 171 spans the rear ends of the pair of lower frames 150. An end of the rod portion 171 is inserted into the second insertion hole 41b (see FIG. 6) of the holder 40.
The rod portion 171 is elastically deformable and has bending characteristics such that, for example, when a force is applied to the rod portion 171 in a bending direction, bending deformation can be visually confirmed.

Figure 8 is a cross-sectional view of the first connecting frame 158 and the second connecting frame 159 of the chair 1, taken perpendicular to the longitudinal direction. As shown in Figures 5 and 8, the cover body 172 includes a front plate portion 173, a main plate portion 174, and a plurality of retaining plates 175. The cover body 172 is an example of a "cover body."

The main plate portion 174 is formed as a long plate extending in the left-right direction. The main plate portion 174 has a main portion 174A that slopes downward toward the rear. The main plate portion 174 can restrict rearward displacement of the first connecting frame 158.

The front plate portion 173 is formed in the shape of a long plate extending in the left-right direction. The front plate portion 173 hangs down from the underside of the main plate portion 174. The front plate portion 173 is formed in the shape of a plate that intersects with the front-to-rear direction. The front plate portion 173 may, for example, be formed in the shape of a plate that is approximately perpendicular to the front-to-rear direction. The front plate portion 173 may also be inclined so that it moves forward or backward as it extends downward from the upper end.

A storage recess 176 is formed on the underside of the cover body 172 by the rear surface 173a of the front plate portion 173 and the underside 174a of the main plate portion 174. The storage recess 176 accommodates at least a portion of the first connecting frame 158. The storage recess 176 is a recess that opens downward. The storage recess 176 is an example of a "recess."

In this embodiment, the first connecting frame 158 engages with the accommodating recess 176 over at least a portion of its length. The first connecting frame 158 may engage with the accommodating recess 176 over a portion of its length (for example, only the central portion) or over its entire length.
When the first connecting frame 158 engages with the accommodation recess 176, it is accommodated in the accommodation recess 176 in a state where its forward and rearward displacement is restricted by, for example, the front plate 173, the main plate 174, and the retaining plate 175. In this case, the accommodation recess is also referred to as an "engagement recess." Note that the first connecting frame 158 does not have to engage with the accommodation recess 176.

The holding plate 175 is shaped like a plate that intersects the left-right direction. For example, the holding plate 175 is shaped like a plate that is perpendicular to the left-right direction. The holding plate 175 is formed from the rear surface 173a of the front plate portion 173 to the underside 174a of the main plate portion 174.

The rear edge of the holding plate 175 is inclined upward toward the rear, so that the rear edge of the holding plate 175 can restrict the first connecting frame 158 from being displaced forward.
The plurality of holding plates 175 are formed at intervals in the left-right direction (the length direction of the cover body 172).

A recess 177 into which the rod portion 171 engages is formed in the retaining plate 175. The recess 177 is formed in a concave shape extending diagonally rearward from the front edge of the retaining plate 175. The rod portion 171 is positioned rearward of the front plate portion 173. The rod portion 171 engages with the recess 177 while its forward movement is restricted by the front plate portion 173.

The cover body 172 functions to cover the first holding portion 113 of the first upholstery material 111, which will be described later. The cover body 172 makes at least a portion of the first holding portion 113 difficult to see from the outside. For example, because the first holding portion 113 is located in a position covered by the cover body 172, when viewed from the front or rear, at least a portion of the first holding portion 113 cannot be seen due to the cover body 172 and the second upholstery material 112 that covers it.

Figure 9 is a perspective view of a portion of chair 1. As shown in Figure 9, main board portion 174 has a curved shape that is convex downward overall. The curved shape of main board portion 174 may be, for example, a circular arc or an elliptical arc. The closer to the center of the length of main board portion 174, the lower it is located.

Because the main plate portion 174 is curved, the first connecting frame 158 is more likely to engage with the storage recess 176 at least in the center of the length of the cover body 172 (see Figure 4). If the first connecting frame 158 is elastically deformable, it will assume a bent shape that follows the shape of the cover body 172. The first connecting frame 158 engages with the storage recess 176 due to its own elasticity when it is deformed so as to be convex downward.

As shown in Figure 7, the fastener 42 is inserted into the third insertion hole 41c and then into the hole of the receiver 43. The tip of the fastener 42 abuts against the innermost surface 154a of the holding recess 154. This restricts left-right displacement of the holder 40, thereby positioning the holder 40 relative to the vertical rod portion 155.

The first connecting frame 158 and the second connecting frame 159 can be assembled to the first rod 124 in the following manner.
The holder 40 has the fasteners 42 retracted to shorten the length by which the fasteners 42 protrude outward in the left-right direction from the holder main body 41. The holders 40 are attached to both ends of the first connecting frame 158 and the rod portion 171. The first connecting frame 158 and the rod portion 171 with the holders 40 attached to both ends are referred to as a "frame with holders."

Attach the cover body 172 to the frame with holder. Insert one end of the frame with holder deeply into the holding recess 154 of one of the vertical rod sections 155. Next, move the frame with holder toward the other vertical rod section 155, and insert the other end of the frame with holder into the holding recess 154 of the other vertical rod section 155. This results in both ends of the frame with holder being inserted into the holding recess 154.

The fastener 42 of the holder 40 is advanced, increasing the length of the fastener 42 that protrudes outward in the left-right direction from the holder body 41. The tip of the fastener 42 abuts against the innermost surface 154a of the holding recess 154. This restricts left-right displacement of the holder 40, positioning the holder-attached frame relative to the vertical rod portion 155.

The holder body 41 may be positioned such that a through-hole with a female thread is formed in the innermost portion of the holding recess 154, and the fastener 42 is fastened to this through-hole. The holder body 41 may be positioned such that a receiving device (nut) to which the fastener 42 is fastened is embedded in the innermost portion of the holding recess 154 by insert molding or the like.

3, the support frame 152 connects the lower frames 150 to each other. The support frame 152 spans the pair of lower frames 150. The support frame 152 includes a pair of connection frames 160 and a support base connection portion 161.
The connection frames 160 extend inward in the left-right direction from each lower frame 150. The support base connecting portion 161 connects the pair of connection frames 160 together.

As shown in FIG. 2, the first upholstery material 111 is fastened to the outer peripheral edge of the seat frame 120, thereby blocking the opening in the seat frame 120 from above. More specifically, the first upholstery material 111 is fastened to the outer peripheral edge of the seat frame 120 and the outer peripheral edge of the lower frame 150. The first upholstery material 111 is fastened to the seat frame 120 and the lower frame 150, for example, by inserting plate-shaped edging material provided on the periphery of the first upholstery material 111 into grooves formed in the seat frame 120 and the lower frame 150. The left and right side edges of the first upholstery material 111 are fastened to the side rod portion 131 and the lower frame 150. The front edge of the first upholstery material 111 is fastened to the front rod portion 130.

The first upholstery material 111 constitutes the seat surface 100a. The first upholstery material 111 is stretched between the pair of side rods 131 and the pair of lower frames 150. The first upholstery material 111 is an example of an "upholstery material."

The second upholstery material 112 is fastened to the outer peripheral edge of the back frame 123, thereby blocking the opening of the back frame 123 from the front. More specifically, the second upholstery material 112 is fastened to the back frame 123 by inserting plate-shaped edge materials provided on the periphery of the second upholstery material 112 into grooves formed in the back frame 123. The left and right side edges of the second upholstery material 112 are fastened to the main rod portion 153. The upper edge of the second upholstery material 112 is fastened to the upper rod portion 157.
The second upholstery material 112 constitutes the back support surface 101a. The second upholstery material 112 is stretched between the pair of vertical rod portions 155 (more specifically, the main rod portions 153).

The first upholstery material 111 and the second upholstery material 112 are, for example, perforated sheet-like upholstery materials. The first upholstery material 111 and the second upholstery material 112 are, for example, mesh materials formed by combining stretchable synthetic resin fibers in a mesh shape. The first upholstery material 111 and the second upholstery material 112 can deform in response to, for example, the rotation of the backrest 101 relative to the seat 100. The first upholstery material 111 and the second upholstery material 112 are see-through. That is, they may be see-through in the thickness direction (i.e., be see-through from one side to the back side).
Examples of perforated sheet-like upholstery materials include mesh materials and punched materials with many through holes. The first upholstery material 111 and the second upholstery material 112 are not limited to perforated sheet-like materials and may be formed, for example, in the form of cloth or film.

As shown in FIG. 8 , the rear end of the first upholstery material 111 is formed with a first holding portion 113, where the first upholstery material 111 is folded back into a loop around the first connecting frame 158. The folded and overlapped first upholstery materials 111 are joined together at the joining portion 114 by sewing, welding, or the like. At the joining portion 114, the first upholstery materials 111 are joined with the same sides overlapping each other. In other words, at the joining portion 114, the front surfaces or back surfaces of the first upholstery materials 111 are overlapped together. In this embodiment, the joining portion 114 extends diagonally downward and forward from the tubular portion 113A.

The first retaining portion 113 includes a cylindrical portion 113A that surrounds the first connecting frame 158, and a connecting portion 114. The first connecting frame 158 is inserted into the first retaining portion 113 (more specifically, the cylindrical portion 113A). The first retaining portion 113 is structured to attach the first upholstery material 111 to the first connecting frame 158. The first retaining portion 113 is an example of an "attachment portion" and a "retaining portion."

The first holding portion 113 and the first connecting frame 158 are covered by the cover body 172. In a side view, at least a portion of the first holding portion 113 is housed in the housing recess 176 of the cover body 172. In this embodiment, in a side view, the first holding portion 113 and the first connecting frame 158 are entirely housed in the housing recess 176. Therefore, the first holding portion 113 is difficult to see from the outside. The first holding portion 113 and the first connecting frame 158 are located in a position enclosed by the cover body 172 in a plan view, except for the portions inserted into the holding recess 154 (see Figure 5).

Fig. 10 is a perspective view showing a cross section of the first connecting frame 158 and the second connecting frame 159 of the chair 1. Fig. 11 is a perspective view showing a cross section of the first connecting frame 158 and the second connecting frame 159 of the chair 1.
10 and 11 , the lower end of the second upholstery material 112 is formed with a cylindrical second retaining portion 115, which surrounds the second connecting frame 159. The structure of the second retaining portion 115 is as follows: the second upholstery material 112 extends downward in front of the second connecting frame 159, passes through the lower end of the front plate portion 173, wraps around under the second connecting frame 159, and enters the storage recess 176.

The second upholstery material 112 passes between the inner surface of the storage recess 176 and the first retaining portion 113, and then passes through the rear end of the main plate portion 174 and wraps around to the rear of the second connecting frame 159. The second upholstery material 112 advances along the upper surface of the main plate portion 174 and is overlapped on the rear surface of the second upholstery material 112 in front of the second connecting frame 159. The overlapped second upholstery materials 112 are joined together at the joining portion 116 by sewing, welding, etc. At the joining portion 116, the second upholstery materials 112 are joined with their different surfaces (front and back surfaces) overlapping each other.

Within the storage recess 176, the second upholstery material 112 is raised by the first connecting frame 158. As a result, the second upholstery material 112 abuts against the lower end of the front plate portion 173 and the rear end of the main plate portion 174.

The second connecting frame 159 is inserted into the second holding portion 115. The second holding portion 115 is a structure (mounting portion) that attaches the second upholstery material 112 to the second connecting frame 159.

The circumferential length of the second holding portion 115 may be constant. That is, the circumferential length of the second holding portion 115 may be the same at any position in the left-right direction.
The second holding portion 115 may be formed so as to extend linearly in the left-right direction when the second connecting frame 159 is not inserted. A linear shape of the second holding portion 115 is easier to manufacture than a portion that is curved in accordance with the curvature of the cover body 172. A linear second holding portion 115 also has the advantage of improving the appearance of the stitching at the joint 116.

The first upholstery material 111 is adjacent to or abutting the lower end of the second retaining portion 115. More specifically, the first upholstery material 111 is adjacent to or abutting the underside of the second upholstery material 112 at the lower end of the front plate portion 173 of the cover body 172. The first upholstery material 111 may be pressed down by the lower end of the front plate portion 173. Because the first upholstery material 111 is adjacent to or abutting the lower end of the second retaining portion 115, there is no gap or only a very small gap between the first upholstery material 111 and the second upholstery material 112. Therefore, when viewed from the front of the chair 1, the first upholstery material 111 and the second upholstery material 112 appear to be continuous with no gap or to be adjacent to each other as a single unit. Therefore, the chair 1 has a good appearance, with a structure in which the first upholstery material 111 and the second upholstery material 112 are stretched between a pair of first rods 124.

FIG. 12 is a perspective view showing a cross section of the first connecting frame 158 and the second connecting frame 159 of the chair 1. As shown in FIG.
As shown in Figure 12, the main plate portion 174 of the cover body 172 has a curved shape. Therefore, the closer to the longitudinal end of the main plate portion 174, the higher the position of the main plate portion 174. Therefore, in the region near the longitudinal end, the main plate portion 174 has a curved shape having a main portion 174A and an end plate portion 174B. The main portion 174A is inclined downward toward the rear. The end plate portion 174B hangs down from the rear end of the main portion 174A. The height dimension of the end plate portion 174B increases as it approaches the longitudinal end.

In a cross section perpendicular to the longitudinal direction of the cover body 172, it is desirable that the perimeter of the circumscribed figure (closed figure) that passes through the front end of the main plate portion 174, the rear end of the main plate portion 174, the outer peripheral surface of the first connecting frame 158, and the lower end of the front plate portion 173 to the front end of the main plate portion 174 be constant regardless of the position along the longitudinal direction of the cover body 172.

When the main plate portion 174 has a main portion 174A and an end plate portion 174B, the circumscribed figure is a figure that passes through the front end portion of the main portion 174A, the rear end portion of the main portion 174A, the lower end portion of the end plate portion 174B, the outer peripheral surface of the first connecting frame 158, and the lower end portion of the front plate portion 173 to the front end portion of the main portion 174A.

In FIG. 12, the perimeter of the circumscribing figure S1, the perimeter of the circumscribing figure S2, and the perimeter of the circumscribing figure S3 are equal.
The circumscribing figure S1 is the circumscribing figure of a cross section perpendicular to the longitudinal direction at position P1 near the end of the cover body 172. The circumscribing figure S2 is the circumscribing figure of a cross section perpendicular to the longitudinal direction at position P2 away from the end of the cover body 172. Position P2 is closer to the center of the length of the cover body 172 than position P1. The circumscribing figure S3 is the circumscribing figure of a cross section perpendicular to the longitudinal direction at position P3 further away from the end of the cover body 172. Position P3 is closer to the center of the length of the cover body 172 than position P2.

The main plate portion 174 at positions P1 and P2 has a main portion 174A and an end plate portion 174B. The height dimension of the end plate portion 174B at position P2 is smaller than the height dimension of the end plate portion 174B at position P1. The main plate portion 174 at position P3 does not have an end plate portion 174B.

If the perimeter of the circumscribing figure of the cover body 172 is constant, the perimeter of the second holding portion 115 can also be constant. This makes it easier to manufacture the second holding portion 115.

<Armrest 4>
1 and 2, the armrests 4 extend from the connecting frame 160 to both the left and right sides, and then extend upward on both the left and right sides of the seat 100. The armrests 4 support the arms and the like of the seated occupant from below.

(Effects of this embodiment)
In the chair 1 of this embodiment, the first retaining portion 113 of the first upholstery material 111 is covered by the cover body 172, making the first retaining portion 113 less visible from the outside. Therefore, the appearance of the chair 1 is not marred by the first retaining portion 113. As a result, the chair 1 has a good appearance.

The first retaining portion 113 of the first upholstery material 111 is folded back in a loop shape, surrounding the first connecting frame 158. Because the structure of the first retaining portion 113 is simple, it is easy to manufacture.

The cover body 172 has a storage recess 176 that stores at least a portion of the first connecting frame 158. This makes it difficult to see the first holding portion 113 from the outside.

The first connecting frame 158 engages with the storage recess 176. This restricts the forward/backward displacement of the first connecting frame 158, making it easier to position the first connecting frame 158 and the cover body 172.

If the first connecting frame 158 is elastically deformable, it will assume a shape that corresponds to the shape of the cover body 172 when the cover body 172 has a curved shape. This makes it easy to position the first connecting frame 158 relative to the cover body 172.
If the first connecting frame 158 is elastically flexible, it will flex and deform in response to the seating load input to the first upholstery material 111, thereby providing a flexible seating feel.

The first connecting frame 158 is located close to the connecting portion 122, making it difficult to form it integrally with the first rod 124. However, because the first connecting frame 158 is separate from the first rod 124, it does not need to be molded integrally with the first rod 124. This means that the structure of the mold used for manufacturing does not become complicated, which helps reduce manufacturing costs.

In the chair 1, the first upholstery material 111 of the seat 100 and the second upholstery material 112 of the backrest 101 are separate bodies, so the load received by the seat 100 is less likely to affect the second upholstery material 112. The load received by the backrest 101 is less likely to affect the first upholstery material 111. This prevents deformation of the first upholstery material 111 and the second upholstery material 112 when a person sits down. This results in a chair 1 that provides excellent seating comfort.

(Other Modifications)
Although preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to these embodiments. Addition, omission, substitution, and other modifications of the configuration are possible without departing from the spirit of the present disclosure. The present disclosure is not limited by the above description, but is limited only by the scope of the appended claims.

In the above-described embodiment, the first upholstery material 111 is attached to the first connecting frame 158 (second rod) by the loop-shaped first retaining portion 113, but the structure by which the upholstery material is attached to the second rod is not particularly limited. For example, the upholstery material may be attached to the second rod by inserting a plate-shaped rim material provided on the periphery of the upholstery material into a groove in the second rod. In this example, the attachment portion is the point where the rim material is inserted into the groove in the second rod.
The upholstery material may be attached to the second rod by a tacker. In this example, the attachment point is where the upholstery material is attached to the second rod by the tacker.

In the above embodiment, the second upholstery material 112 is attached to the second connecting frame 159 by the cylindrical second retaining portion 115, but the structure by which the second upholstery material is attached to the second connecting frame does not have to be a cylindrical retaining portion that surrounds the second connecting frame. For example, the attachment structure may be such that the edge material of the second upholstery material is inserted into a groove in the cover body.

In the above-described embodiment, the cover body 172 has a structure including a front plate portion 173 and a main plate portion 174, but the structure of the cover body is not particularly limited. The cover body may have a structure including, for example, a main plate, a front plate hanging down from the front end of the main plate, and a rear plate hanging down from the rear end of the main plate. This cover body can accommodate the second rod and the attachment portion in an internal space (accommodation recess) surrounded by the main plate, front plate, and rear plate. The cover body may have, for example, a half-pipe shape. This cover body can accommodate the second rod and the attachment portion in an internal space (accommodation recess).
In addition, within the scope of the present disclosure, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described modified examples may be combined as appropriate.

1... chair 2... support structure 3... chair body (chair load support member)
100... seat 100a... seat surface (load bearing surface)
101... Backrest 111... First upholstery material (upholstery material)
113...First holding portion (holding portion, mounting portion)
120... Seat frame 122... Connection portion 123... Back frame 124... First rod 131... Side rod portion 155... Vertical rod portion 157... Upper rod portion 158... First connection frame (second rod)
172... Cover body 176... Storage recess (recess)

Claims (6)

A pair of first rods arranged at a distance from each other;
A tension member stretched between the pair of first rods and having a load-receiving surface formed thereon to receive the load of a seated person;
a second rod that is spanned between the pair of first rods and to which the tension member is attached;
a cover body that covers the attachment portion where the upholstery material is attached to the second rod ,
The first rod body includes a side rod portion constituting a seat frame which is an outer shell of the seat, and a vertical rod portion constituting a back frame which is an outer shell of the backrest,
the tension member is a first tension member stretched between the pair of side rod portions,
A second tension member is stretched between the pair of vertical rod portions,
the cover body has a main plate portion and a front plate portion extending from the main plate portion, and a recess portion that accommodates at least a portion of the mounting portion is formed by a lower surface of the main plate portion and a rear surface of the front plate portion,
the second upholstery member has a second attachment portion attached to the cover body,
The first upholstery material extends from the attachment portion and is adjacent to or abuts the second upholstery material at a lower end of the front panel portion.
Load-bearing member for chairs. The load-supporting member for a chair according to claim 1, wherein the attachment portion is a retaining portion in which the upholstery material is folded back in a loop shape around the second rod. The load-bearing member for a chair according to claim 1 or 2 , wherein the second rod engages with the recess. The load-supporting member for a chair according to any one of claims 1 to 3 , wherein the second rod is elastically deformable. The side rod portion and the vertical rod portion are connected at a connecting portion,
The back frame has an upper rod portion that connects upper ends of the pair of vertical rod portions,
The second rod is separate from the first rod and is provided at a position of the vertical rod portion closer to the connecting portion than the upper rod portion.
The load-supporting member for a chair according to any one of claims 1 to 4 . A load-supporting member for a chair according to any one of claims 1 to 5 ;
a support structure for supporting the chair load support member.