JP2018089407A - Chair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chair capable of stably supporting a body of a sitter by supporting a lumbar part of the sitter in a further wide range by a lumber support.SOLUTION: The chair includes a pair of vertical rods constituting a part of a back frame; a mesh fabric tightly stretched between the vertical rods; and a lumbar support disposed at the back face side of the mesh fabric within a range of a vertically intermediate part and having both ends fitted to the vertical rods. The lumbar support includes six belt strips 62a-62f extending in the horizontal direction and disposed parallel to each other in the vertical direction, where flexibility of the belt strips 62a, 62b, 62e, and 62f is set larger compared with that of belt strips 62c and 62d located at a vertically central part.SELECTED DRAWING: Figure 13

Description

  The present invention relates to a chair provided with a lumbar support that is attached to the back of a back and supports a waist of a seated person.

  2. Description of the Related Art Conventionally, a chair having a back frame structure in which a back constituting the chair is configured by attaching a tension material to the back frame is known. As such a chair, there exists a thing of the following patent document 1, for example. In this structure, a back frame and a seat frame are integrally configured, and a seating surface is formed by attaching a mesh ground to an opening formed in the back frame and the seat frame.

  Furthermore, in a chair with such a back frame structure, as described in Patent Document 2 below, it is also effective to attach a lumbar support for the purpose of reducing the burden on the waist. The lumbar support is usually in the form of a belt, and is provided so as to be bridged to the left and right of the back frame on the back surface of the tension member. And the waist part can be supported with a tension material by producing the reaction force which opposes the load to the back by a waist part.

  In addition, the lumbar support described in Patent Document 2 has a structure in which the left and right sides of the lumbar support main body portion formed in a block shape are supported by a pair of support portions formed in a thin strip shape. The lumbar support main body part can be moved to an appropriate position along the waist of the seated person by deforming the support part exclusively when leaning on the back.

JP 2007-260118 A JP 2008-119411 A

  However, in the configuration described in Patent Document 2 described above, the lumbar support main body portion is hardly expected to be deformed with respect to the left and right support portions. The waist may not be supported. Then, it is assumed that the load when the seated person leans back can concentrate on a part of the waist and cannot be kept stable.

  An object of the present invention is to effectively solve such a problem. Specifically, the lumbar support can support the waist of the seated person in a wide range, and stably supports the body of the seated person. An object is to provide a chair that can.

  In order to achieve this object, the present invention takes the following measures.

  That is, the chair of the present invention includes a pair of vertical eaves constituting a part of the back frame, a tension member stretched between these vertical eaves, and a vertical direction of the tension member on the back side of the tension member A lumbar support that is arranged in the range of the intermediate portion and has both ends attached to the downspout, wherein the lumbar support extends in the left-right direction and is arranged in parallel in the up-down direction. One strip is provided, and it is characterized in that it is configured to increase the flexibility of the strip at a position separated upward or downward as compared with the strip at a specific position in the vertical direction.

  With this configuration, since the flexibility of the strip at a specific position in the vertical direction is relatively small, when the occupant leans on the back and the tension material bends backward, the waist is It is possible to support it firmly and make the lumbar support function effectively. Furthermore, since the strips at a position further upward or downward than that are relatively flexible, the shape of the strip along the waist is formed starting from the strip at a specific position in the upper and lower directions. By bending, the whole lumbar support becomes a reasonable form that does not cause a burden on a part of the waist, and it becomes possible to support the entire waist appropriately.

  In order to give the strip a great flexibility while not causing a sense of incongruity to the seated person, it is configured to provide a deformation permitting portion for causing the bending in the left and right end portions of the strip. Is preferred.

  In order to make it possible to increase the flexibility of the strip at a position separated upward or downward from the strip at a specific position in the vertical direction while having a simple configuration, the deformation permission portion includes: It is preferable that the arm portion is taken up in the vertical direction from the end portion of the strip at a specific position in the vertical direction and connected to the end portion of the strip at a position separated upward or downward. .

  In order to suppress the bending of the strip at a specific position in the vertical direction and to make a difference in the flexibility of the strips arranged in the vertical direction, a fixing portion for regulating the bending of the strip is provided. It is preferable that the structure is provided in the vicinity of the end of the strip at a specific position in the vertical direction.

  Furthermore, in order to make it possible to greatly change the support strength of the lumbar part by the entire lumbar support, the fixed part regulates the movement of the end of the strip at a specific position in the vertical direction, and the amount of regulation It is preferable that the flexibility of the strip at a specific position in the vertical direction can be changed by changing the length.

  The entire lumbar support is bent more naturally so that the contact pressure against the body does not become excessive excessively, and the tension material is prevented from bending greatly in the vicinity of the upper and lower ends of the lumbar support. In order to reduce dynamic resistance and prevent damage to the upholstery material, the strip at a specific position in the vertical direction is a strip located in the central portion in the vertical direction, and is different adjacent to the vertical direction of the strip. It is preferable that the strip is provided.

  In order to obtain a good appearance while maintaining the flatness of the tension member without the lumbar support interfering with the tension member only by being attached to the vertical arm, the vertical arm is not provided with the tension member. A support surface for supporting the material is provided in the front part, and a relief area gradually separated from the tension material is formed at a position inside the support surface toward the inside, and the lumbar support It is preferable to be configured to be attached to the escape area.

  In addition, in order to obtain the same effect of properly supporting the entire waist by the lumbar support while using a mode different from the above, a pair of vertical fins constituting a part of the back frame, and these And a lumbar support that is arranged in the range of the middle part in the vertical direction of the tension material on the back side of the tension material, and that has both ends attached to the vertical collar. Preferably, the lumbar support has a structure in which the upper and lower edge portions are bent to follow the bending of the tension member, and is preferably configured so that the flexibility becomes smaller toward the central portion in the vertical direction. It is.

  According to the present invention described above, it is possible to provide a chair that can appropriately support the waist of the seated person in a wide range by the lumbar support and can stably support the body of the seated person. .

The perspective view which shows the chair which concerns on one Embodiment of this invention. The side view of the chair. The front view in the state which removed the mesh ground and the lumbar support from the chair. The enlarged end elevation which cut | disconnected the vertical shaft of the chair in the AA position of FIG. The expanded end elevation which cut | disconnected the upper frame part of the chair in the BB position of FIG. The expansion perspective view which shows the principal part of the back frame of the chair. The expansion perspective view which shows the lower frame part periphery of the back frame which comprises the chair. The expansion perspective view which shows the state which removed the groove formation member from the state of FIG. The enlarged end elevation which cut and showed the lower frame part of the chair in CC position of Drawing 7 typically. The schematic diagram which decomposes | disassembles and shows the mesh ground and strip which comprise the chair. The perspective view which expands and shows the back frame and lumbar support which comprise the chair. The rear view which expands and shows a part of same back frame and lumbar support. The perspective view which decomposes | disassembles and shows the lumbar support. The perspective view which expands and shows the attachment part periphery of the lumbar support in a vertical shaft The enlarged end view which cut | disconnected the end part of a vertical shaft and a lumbar support in the VV position of FIG. The enlarged end view which cut | disconnected the end part of the vertical shaft and the lumbar support in the WW position of FIG. Explanatory drawing which shows the state which enlarged the amount of regulation by a stopper member in the same lumbar support. Explanatory drawing which shows the state which provided the load from the back to a lumbar support from the state of FIG. Explanatory drawing which shows the state which made the restriction amount by a stopper member small in the same lumbar support. Explanatory drawing which shows the state which provided the load from the back to the lumbar support from the state of FIG. The end view which cut | disconnected the lumbar support main body in the state of FIG. 17, 18 in the P1-P1 position and the P2-P2 position. The schematic diagram which shows the structure of a lumbar support main body. The disassembled perspective view which shows the example which deform | transformed the lumbar support. The perspective view which looked at the lumbar support main body shown in FIG. 23 from the back side. The perspective view which shows the modification of the lumbar support different from FIG. The schematic diagram which shows the modification of a lumbar support main body. The schematic diagram which shows the modification of the lumbar support main body different from FIG. The schematic diagram which shows the modification of the lumbar support main body different from FIG. The schematic diagram which shows the modification of the lumbar support main body different from FIGS. The schematic diagram which shows the modification of the lumbar support main body different from FIGS.

  Embodiments of the present invention will be described below with reference to the drawings.

  In the chair of this embodiment, as shown in FIG. 1, a seat 2 is arranged above a leg 1 and a back 3 is erected on the back of the seat 2, and the seat 2 and the back 3 are placed by the leg 1. It is configured as a swivel chair supported rotatably.

  Here, in the embodiment of the present application, when the direction is indicated, the terms “vertical direction”, “front / rear direction”, and “left / right direction” are used, which are the same as the general direction when the chair is raised as shown in FIG. , A vertical direction (Z direction in the figure), a direction substantially perpendicular to the spine 3 (X direction in the figure), a vertical direction and a direction perpendicular to the front-rear direction (Y direction in the figure).

  The structure of the chair will be described in detail. The leg 1 is configured such that the leg strut 12 is rotatably supported at the center of five leg blades 11 to 11 that extend radially and have casters 11a at the tips. As shown in FIG. 2, a support base 13 serving as a basis for supporting the back 3 and the seat 2 is provided at the upper end 12 a of the leg column 12. A gas spring (not shown) is incorporated in the leg column 12, and the upper end 12 a of the leg column 12 can be moved up and down together with the support base 13 by operating this.

  The support base portion 13 is formed of a rigid body such as an aluminum die cast, extends slightly forward and forward from the leg column 12, and the tip 13 a supports the front portion 21 a of the seat 21. A seat surface 22 including a cushion is provided in the upper portion of the seat receiver 21, and the seat 2 is configured by these.

  Further, the support base 13 rotatably supports a back support rod 14 formed of a metal frame at the left and right positions of the leg support 12, and the back support rod 14 extends rearward and upward. A back frame 31 as a frame is provided at the tip 14a. Further, the rear portion 21b of the seat receiver 21 is rotatably supported at a position midway from the position where the back support rod 14 is supported by the support base 13 toward the tip 14a. Therefore, the back frame 31 and the seat receiver 21 operate in conjunction with the support base 13 while a part of the rotation fulcrum slides, so that a so-called synchro-rocking operation is possible.

  A gas spring type reaction force mechanism 14 s (see FIG. 7) is provided inside the back support rod 14 so as to generate a reaction force against the rearward tilt of the back frame 31. Similarly, a reaction force mechanism (not shown) is also provided inside the support base 13 so as to generate a reaction force against the movement of the seat receiver 21. A resin cover 15 is divided into a plurality of parts around the back support rod 14 and is configured to cover the back support rod 14 together with the reaction force mechanism 14s described above.

  As will be described later, the back frame 31 is provided with a mounting groove G that is open on the outer peripheral side in order to attach a mesh ground 38 that is a tension material. 38 can be attached by inserting an edge 38a (see FIG. 10), and the spine 3 is configured together with the mesh ground 38.

  As shown in FIG. 2, the back frame 31 is inclined slightly rearward as a whole, and is reduced in size in the front-rear direction while being curved upward from below. The back frame 31 is provided with a lumbar support 6 as an optional member as shown in FIG. The lumbar support 6 is disposed on the back surface of the mesh ground 38, and can support the waist through the mesh ground 38 when a seated person leans against the back 3.

  Hereinafter, first, the description will be focused on the configuration of the back frame 31. Therefore, in FIGS. 3, 7, and 8, a mounting portion 76 (FIG. 14) described later for mounting the lumbar support 6 (see FIG. 1) is omitted.

  FIG. 3 shows a state in which the mesh ground 38 and the lumbar support 6 are removed from the chair and viewed from the front. The back frame 31 is configured by a frame main body 32 and a groove forming member 36 that forms the above-described mounting groove G (see FIG. 2) in cooperation with the frame main body 32 by attaching to the frame main body 32.

  The frame body 32 is composed of a pair of vertical rods 33, 33 extending in the vertical direction, and a pair of horizontal rods 34, 35 that connect the upper and lower portions to each other. Is formed with a substantially rectangular opening OP. The frame body 32 is molded by resin integral molding using a mold, but can be molded using a metal material such as aluminum.

  The vertical rods 33, 33 arranged on the left and right have a symmetrical shape, but the horizontal rods 34, 35 arranged on the upper and lower sides have completely different functions because they have different functions. Therefore, in the following, the upper reed is referred to as the upper frame portion 34, and the lower recumbent is referred to as the lower frame portion 35.

  When viewed from the front, the vertical rods 33 and 33 are arranged with the interval slightly narrowed upward. Therefore, the spine 3 is configured to become slightly smaller upward. The upper frame portion 34 connected to these is formed to be slightly curved so that the center is convex upward, and the connection portion with the vertical rods 33 and 33 is formed by a smooth arc. The lower frame portion 35 is also formed so as to be connected to the vertical rods 33 and 33 by a smooth curve, and is configured such that the center dimension is about twice as large as the center in both the left and right direction ends. (Refer to FIG. 7), and the back support rod 14 described above is connected to the center portion.

  As shown in FIG. 2, the vertical rod 33 is provided with a curved portion and an inclined portion in a side view from the bottom to the top. Specifically, immediately above the connecting portion with the lower frame portion 15, a first region R1 that is a curved portion in which the front surface 33a that is a support surface is curved so as to be convex forward, and above the first region R1 The second region R2 that is curved in the direction opposite to the first region R1 so that the front surface 33a is concave toward the front, and the third region that is set above and tilts the front surface 33a toward the rear It is a shape based on an ergonomic viewpoint provided with R3. As shown in the figure, the human spine line LB draws a gentle S-curve, so that the vertical rod 33 also draws a substantially similar curve in a side view. That is, the first region R1 is a waist region that is set at the height position of the waist when a person with a standard figure is seated, and the second region R2 is when the person with the standard figure is seated. The lumbar region and the back region have a shape that substantially matches the curvature of the seated person's spine in a side view. Further, the third region R3 is a shoulder region that is provided at the height position of a standard human body's shoulder and is shaped to separate the back frame 31 from the shoulder of the seated person. The aforementioned lumbar support 6 (see FIG. 1) is provided in the first region R1.

  By attaching the mesh ground 38 to such a vertical rod 33, the mesh ground 38 can be shaped along the front surface 33 a of the vertical rod 33. That is, a waist region (first region R1), a back region (second region R2), and a shoulder region (third region) can be formed on the entire support surface of the seated person on the back 3. Therefore, based on an ergonomic point of view, the waist and back can be supported along the curvature of the human spine, and the body can be held in an appropriate posture with little fatigue even when sitting for a long time. Also, in the shoulder area, based on ergonomics, it is possible to secure a space around the shoulder to make it easier to move the arm and improve work efficiency, and as a support area for relaxing when the upper body is warped It can be used. Since the shoulder region is formed so as to be separated from the shoulder, it does not necessarily have to be provided at the same height as the shoulder as long as it is above the back region, and is slightly lower than the shoulder. Even when formed, the above-described effects can be obtained.

  Here, the AA position in FIG. 3, that is, the end face shape when the vertical hook 33 is cut in the second region R2, is shown in FIG. As shown in this figure, the vertical rod 33 is formed as a plane portion in which the front surface 33a serving as a support surface of the mesh ground 38 is substantially orthogonal to the front-rear direction, and is generally orthogonal to the front surface 33a, that is, It has a shape extending toward the rear. Furthermore, the outer side surface 33b continuing to the outer side of the front surface 33a is formed so as to be inclined inward as it goes rearward. On the inner side of the front surface 33a, a relief surface 33c that inclines inward as it goes rearward is formed, and an inner side surface 33d that inclines toward the outside as it goes rearward is formed continuously with the escape surface 33c. A rear surface 33e is formed between the inner surface 33d and the outer surface 33b. Further, most of the front surface 33a, the outer surface 33b, the clearance surface 33c, the inner surface 33d and the rear surface 33e are connected to each other by smooth curved surfaces. A region formed by adding the flank 33c to the curved surface connecting the front surface 33a and the flank 33c is a flank region Rc that is set inside the front surface 33a and gradually moves away from the mesh ground 38 toward the inside.

  A mounting groove 33g is formed at a position in the vicinity of the front surface 33a in the outer side surface 33b so as to be substantially parallel to the front surface 33a, that is, with the outer peripheral side as an opening direction, and an edge 38a (see FIG. 10) is formed in the mounting groove 33g. When the mesh ground 38 is inserted and attached, the mesh ground 38 is stretched inward from the outer surface 33b via the front surface 33a. Therefore, the front surface 33a functions as a support surface that regulates the position of the mesh ground 38 and contributes to the formation of the overall shape. In addition, since the relief region Rc is formed inside the front surface 33a that is the support surface, the mesh ground 38 hardly affects the cross-sectional area of the entire vertical rod 33, that is, does not cause a decrease in strength. The support area is reduced to make it easier to bend. Furthermore, although the flank 33c is separated from the mesh base 38 in a normal state, when the mesh base 38 is deformed by leaning on a person, it is possible to increase the stability by contacting the mesh base 38. It has become.

  The front surface 33a is designed to have a certain area or more, so that when the seated person shifts his / her posture from side to side, he / she does not bite into his / her back to cause discomfort or discomfort. Further, a relief surface 33c is formed on the inner side of the front surface 33a so as not to form an acute corner, thereby relieving contact with the body. The upper frame portion 34 has a shape that is recessed like a wing cross section toward the rear from the front surface and the flank 33c that can come into contact with the body of the seated person. Furthermore, the rear surface 33e is formed to be sufficiently smaller than the front surface 33a, so that the shape feature is more prominent. In addition, when a simpler shape is assumed in which the inner surface 33c and the front surface 33a are extended without forming the flank 33c, it can also be said that the sectional view is substantially triangular. The vertical rod 33 has such a cross-sectional shape so that the front-rear dimension L2 is larger than the left-right dimension L1 (in the present embodiment, approximately twice). From the viewpoint of the amount of material used, strength, and design, the front-rear dimension L2 is preferably 1.5 times to 3 times the left-right dimension L1. Because of the dimensional relationship as described above, there are few visible portions of the vertical hook 33 through the mesh ground 38 in the front view, and a more refined impression can be given. In addition, since the load on the vertical rod 33 mainly acts as a result of the seat occupant leaning backward, it is possible to ensure the strength against the load on the rear by increasing the front-rear dimension L2. It has become.

  In other words, the vertical rod 33 has a reverse triangle shape with respect to the front and rear dimensions of the front half portion in which the front surface 33a and the flank surface 33c functioning as pressure-receiving surfaces and the groove 33g functioning as a tension member attachment location are formed. The thickness of the latter half of the shape is almost the same or greater.

  The vertical rod 33 has substantially the same shape along the vertical direction including not only the second region R2 but also the first region R1. That is, since the dimension in the front-rear direction (front-rear dimension L2) is smaller than the dimension in the left-right direction (left-right dimension L1), the first region R1, second region R2, It is possible to appropriately form the three regions R3.

  As described above, the front-rear dimension L2 becomes smaller (in the present embodiment, about 1/2) as it goes upward, but the left-right dimension L1 is hardly changed (see FIG. 3). The ratio of the upper front-rear dimension to the lower front-rear dimension L2 is preferably about 30 to 60%. Due to the dimensional relationship as described above, it appears that the size of the vertical hook 33 hardly changes between the upper part and the lower part in a front view, and a stable impression can be given (see FIG. 2). In addition, the bending moment due to the backward load caused by the seated person leaning on is larger toward the lower side of the vertical rod 33 and smaller toward the upper side. Therefore, as described above, the longitudinal dimension L2 is decreased toward the upper side. However, there is no shortage of strength, and it is possible to produce a refined impression that the upper part is thinner in a side view, and it is also possible to reduce the manufacturing cost by reducing the material.

  Next, the shape of the upper frame portion 34 will be described. FIG. 5 shows a cross-sectional shape when the upper frame portion 34 is cut at the BB position in FIG.

  As shown in this figure, the upper frame portion 34 is formed as a flat portion with the front surface 34a extending obliquely upward, and an upper surface 34b that is inclined downward toward the rear continuously above the front surface 34a is formed. Has been. In addition, a relief surface 34c that slopes downward as it goes rearward downward from the front surface is formed, and a lower surface 34d that slopes upward as it goes rearward is formed continuously from the relief surface 34c. ing. Adjacent ones of the front surface 34a, the upper surface 34b, the flank surface 34c, and the lower surface 34d are connected by a smooth curved surface. Similar to the vertical rod 33 (see FIG. 4) described above, a region obtained by adding the flank 34c to the curved surface connecting the front surface 34a and the flank 34c is set on the inner side of the front surface 34a and gradually meshes toward the inner side. This is an escape region Rc that is spaced apart from 38.

  Of the curved surface connecting the front surface 34a and the flank 34c, the most forwardly protruding portion constitutes the leading edge Ef along the extending direction of the upper frame portion 34, and is a curved surface connecting the upper surface 34b and the lower surface 34d. Of these, the rearmost protruding portion constitutes the rear edge Er along the extending direction of the upper frame portion 34.

  A mounting groove 34g is formed in the upper surface 34b at a position forward from the center position in the front-rear direction, specifically, at a position near the front surface 34a, substantially parallel to the front surface 34a, that is, with the outer peripheral side as the opening direction. If the mesh ground 38 is attached by inserting the edge 38a (see FIG. 10) into the mounting groove 34g, the mesh ground 38 extends from the upper surface 34b along the front surface 34a, and the shape of the upper portion of the vertical rod 33 Will be arranged diagonally downward.

  Like the front surface 33a of the vertical rod 33, the front surface 34a functions as a support surface that supports the mesh ground 38. Since the escape region Rc is formed inside the front surface 34a that is the support surface, the upper frame The support area of the mesh ground 38 is reduced without substantially affecting the cross-sectional area of the entire portion 34, that is, without causing a decrease in strength, so that bending is easily caused. Furthermore, the front surface 34a has a certain area or more, and when the seated person makes his / her body bow, the upper frame portion 34 bites into the back. It does not cause discomfort or discomfort. In addition, a relief surface 34c is formed below the front surface 34a so as not to form an acute corner, thereby softening contact with the body. And the upper frame part 34 is made into the shape which became constricted like the wing | blade cross section toward the back from the front surface 34a and flank 34c which can contact a seated person's body. In addition, when the simple shape which does not provide the flank 34c is assumed, it can be said that it is formed in the cross-sectional view substantially triangular shape which goes to the rear edge Er from the front surface 34a. By doing so, the front-rear dimension L4 is made larger than the vertical dimension L3 (in the present embodiment, approximately 1.7 times). From the viewpoint of the amount of material used, strength, and design, the front-rear dimension L4 is preferably 1.4 times to 2.5 times the left-right dimension L3. Because of the above dimensional relationship, it is possible to give a more refined impression with fewer visible parts of the upper frame part 34 through the mesh ground 38 in the front view as with the vertical gutter 33. It is possible to ensure the strength against the backward load that mainly acts.

  In other words, like the vertical rod 33, the upper frame portion 34 also has a front-rear dimension and a front-rear dimension in which a front surface 34a and a flank surface 34c that function as pressure-receiving surfaces and a groove 34g that functions as a tension member attachment location are formed. The thickness of the latter half of the inverted triangular shape is almost the same or larger.

  The upper frame portion 34 and the vertical rod 33 are smoothly continuous as shown in FIG. 6, and the mounting grooves 34g and 33g provided in each are also formed to be continuous. Therefore, the mesh ground 38 is stretched while forming a smooth surface between the upper frame portion 34 and the vertical rod 33.

  Next, the shape of the lower frame part 35 will be described. Since the lower frame portion 35 is connected to the back support rod 14 as described above, the lower frame portion 35 is configured to be larger than the other vertical rod 33 or the like as shown in FIG. The back support rod 14 is screwed to the lower surface of the lower frame portion 35, and the reaction force mechanism 14s described above is provided therein.

  The lower frame portion 35 is connected to the upper plate portion 35a extending in the left-right direction and constituting a part of the peripheral edge of the above-described opening, and the lower frame 35 is connected to the center of the rear portion of the upper plate portion 35a. It is comprised by the board part 35b and the side board parts 35c and 35c connected to the lower board part 35b and the upper board part 35a from the right and left vertical rods 33 and 33, and is mutually connected by the smooth curved surface. As a result, the lower frame part 35 forms a concave internal space S that is opened forward and the opening forms a substantially inverted trapezoid. The internal space S also functions as a meat stealer in molding, contributing to the reduction of materials and weight reduction. Further, the lower plate portion 35b is set to have a larger size in the front-rear direction than the upper plate portion 35a in order to ensure a wide mounting space for the back support rod 14 that supports the entire back 3. The lower plate portion 35b also functions as a support rod continuous with the back support rod 14, and is formed integrally with the frame main body 32, so that the number of parts can be reduced and an overall sense of unity can be obtained. An appearance can be obtained. If this is not a problem, the lower plate portion 35b and the side plate portions 35c and 35c can be configured separately from the frame main body 32. The lower frame portion 35 as a whole has a shape that is longer in the front-rear direction than the vertical frame 33 and the upper frame portion 34, and gives a more unified and refined excellent design. ing.

  However, unlike the vertical rod 33 and the upper frame portion 34, the mesh ground 38 interferes with the back support rod 14 even if the mounting groove G having the outer peripheral side as the opening direction is formed in the lower plate portion 35 b and the side plate portion 35 c. For this reason, it becomes impossible to perform installation. For this reason, a mounting groove 35g having an outer peripheral side in the open direction is formed below the upper plate portion 35a in the lower frame portion 35, and is configured to be continuous with the mounting grooves 33g and 34g of the vertical rod 33 and the upper frame portion 34. Can be considered. However, since the lower frame portion 35 is formed with the internal space S opened forward as described above, when the lower frame portion 35 is molded using a mold, the mold The pulling direction is set to the front-rear direction. Therefore, the mounting groove G is formed on the upper plate part 35a whose lower part is covered by the lower plate part 35b, that is, at the position overlapped by the lower plate part 35b when viewed from the outer peripheral side, even if a slide mold is used. It is difficult to do. With regard to the above points, when focusing on the positional relationship with the attachment groove G as the center, the attachment groove 35g formed in the lower frame portion 35 for attaching the mesh ground 38 intersects the surface extending in the opening direction (outer peripheral direction). It can be considered that the lower plate portion 35b having another structure is integrally provided at the position where the operation is performed.

  Therefore, in the present embodiment, as shown in FIG. 8, the mounting groove 35 g (see FIG. 9) is formed by mounting the groove forming member 36 along the upper plate portion 35 a in the internal space S of the lower frame portion 35. It is possible to do. Since the internal space S is largely open to the groove forming member 36, it is possible to easily perform the attaching operation. The groove forming member 36 is a flat plate member along the upper plate portion 35a, and the through holes 36a are formed at five positions spaced apart in the left-right direction. And the back frame 31 which is a frame body is comprised with the frame main body 32 by screwing using this through-hole 36a and the screw hole 35d1 formed in the lower frame part 35. As shown in FIG.

  Specifically, as shown in FIG. 9, the upper plate portion 35a is provided with a step portion 35d formed by being recessed backward, and the screw hole 35d1 described above is formed in the step portion 35d. A recess 35e formed by further recessing is provided below the step 35d. Then, by attaching the groove forming member 36 to the stepped portion 35d, it is possible to form the attachment groove 35g between the concave portion 35e and the groove forming member 36.

  The mounting groove 35g is formed over substantially the entire circumference of the back frame 31 provided with the opening OP together with the mounting grooves 33g and 34g formed in the vertical rod 33 and the upper frame portion 34, for attaching the mesh ground 38. A substantially continuous mounting groove G is formed. As shown in FIG. 7, the mounting groove 33 g formed in the vertical rod 33 is interrupted at a position close to the lower frame portion 35, and the mounting groove 35 g formed by the lower frame portion 35 and the groove forming member 36 is Not continuous. However, since the end portions of both the mounting grooves 33g and 35g are formed in a continuous positional relationship when they are extended to each other, it can be considered that they are substantially continuous. Of course, by changing the shape of each member, the mounting groove G can be configured to be completely continuous.

  When the mesh ground 38 is attached, the groove forming member 36 is covered with the lower frame portion 35 and the mesh ground 38, so that the groove forming member 36 hardly stands out and the back frame 31 is connected to the frame main body 32. Even if divided into the groove forming member 36, the design is not impaired. Further, the mesh ground 38 is attached to the lower frame portion 35 constituting the back frame 31, thereby covering the entire opening OP formed in the back frame 31, creating a sense of unity of the entire back 3, and the back 3 Since it is arranged below the seat 2 in the front view (see FIG. 3), it is possible to have a more luxurious design.

  Here, as shown in FIG. 10, the mesh ground 38 is cut into a back shape and a band-shaped reinforcing band 39 is attached to the edge 38a inserted into the mounting groove G (see FIG. 2) by sewing. Therefore, the mesh ground 38 is configured so that the edge 38a is inserted into the mounting groove G together with the reinforcing band 39, so that the mesh 38 can be held in a firmly inserted position and the form can be stabilized. The portions corresponding to the vertical rods 33 and 33 and the upper frame portion 34 are attached by sewing three-dimensionally while bending one reinforcing band 39, and only another reinforcing band only on the portion corresponding to the lower frame portion 35. 39 is attached. Between the two reinforcing bands 39, 39 is a portion located between the mounting groove 33 g formed in the vertical rod 33 and the groove 35 g provided in the lower frame portion 35, and a simple recess 38 b to which the reinforcing band 39 is not attached. Only fraying processing of the mesh ground 38 is performed.

  In this way, the mesh ground 38 is inserted into the attachment groove G formed over substantially the entire circumference of the back frame 31 so as to be stretched along the shape of the back frame 31 to constitute the back 3. Yes. Since the mounting groove G is formed with the outer peripheral side open at each position, the edge 38a of the mesh base 38 can be easily inserted, and the mounting work can be easily performed. Further, since the mesh ground 38 extends in a direction approximately 180 ° opposite to the mounting groove G, the direction in which the tension acts and the opening direction of the mounting groove G are almost opposite to each other, and do not come off easily. .

  Moreover, the front surface of the back 3 can be made into an appropriate shape by attaching the mesh ground 38 to the attachment groove G of the back frame 31. Specifically, as described above with reference to FIG. 2, the vertical rod 33 has a first region R <b> 1, a second region R <b> 2, and a third region R <b> 3 formed from below in a side view. The mesh ground 38 is stretched while generating undulations and a flat surface, and the entire back 3 can be easily maintained in this shape. Therefore, despite the relatively simple structure in which the mesh ground 38 is attached to the back frame 31, the shape of the back 3 can be made comfortable and suitable for the body of the seated person.

  Hereinafter, the configuration of the lumbar support 6 attached to the back frame 31 will be described in detail. As shown in FIG. 1, the lumbar support 6 is attached to the first region R1 (see FIG. 2) of the vertical rods 33, 33 constituting the back frame 31, constitutes the spine 3, and the seating person's support surface By being arranged on the back side of the mesh place 38, the waist of the seated person can be supported via the mesh place 38. Further, the lumbar support 6 can be attached by using the relief region Rc (see FIG. 4) in the vertical rod 31 described above.

  As shown in FIG. 11, the lumbar support 6 is roughly composed of a lumbar support main body 61 that has flexibility and supports the waist of the seated person, and a support part 70 for supporting the lumbar support body. ing. This figure shows a state in which the lumbar support 6 is exposed by removing the mesh ground 38 (see FIG. 1). The right end 61a as one end of the lumbar support body 61 is attached to one vertical rod 33A (33) constituting the back frame 31, and the left end 61b as the other end is connected to the other through the support 70. It is attached to the vertical rod 33B (33). Hereinafter, the end located on the right side of the lumbar support main body in front view is referred to as a right end 61a, and the end located on the left is referred to as a left end 61b. Both end portions 61 a and 61 b of the lumbar support main body 61 function as attachment portions for being attached to the vertical rod 33 directly or indirectly. The support part 70 has a rectangular parallelepiped box shape that is thin in the front-rear direction, and is mainly composed of a support case 71 that is a main body part and a lid part 72 that is a restricting member attached to the front surface of the support case 71.

  The lumbar support body 61 is formed into a thin plate shape with a resin such as polypropylene, and a plurality (six in this embodiment) of strips 62 to 62 extending in the left-right direction are arranged in parallel at equal intervals up and down. It has a shape. The strips 62 to 62 are not limited to six and can be appropriately changed. The strips 62 to 62 are formed with a substantially constant width in the left-right direction, and can be independently bent and deformed. Further, the strips 62 to 62 are arranged in a plane substantially parallel to the mesh ground 38 (see FIG. 1) constituting the spine 3, so that any of the strips 62 to 62 appropriately supports the waist of the seated person. Can be done. Since it is comprised as mentioned above, between the strips 62-62, the slits 63-63 which have a substantially constant width | variety are formed in the left-right direction, In addition to the independent bending function of each strip 62-62, , It has come to give a design that makes the appearance impression refreshing and light.

  Further, the lumbar support body 61 is formed of a translucent material, and coupled with the transmission of light by the mesh ground 38, the light is transmitted in a wider area of the back 3 and a lighter impression is obtained. It is possible to give.

  FIG. 12 shows the lumbar support 6 viewed from the back. On the back side of the support case 71, an operation lever 73, which is an operation unit for changing the amount of restriction of the displacement of the lumbar support 6, is provided.

  FIG. 13 shows a state where the lumbar support 6 is disassembled. As described above, the lumbar support main body 61 is formed in a thin plate shape having the front-rear direction as the thickness direction, and has a laterally long rectangular appearance in front view. The right end 61a side is formed to be slightly thicker, and the back side is a tapered surface 61d along the relief surface 33c (see FIGS. 4 and 11) of the vertical rod 33A. In addition, screw insertion holes 61e and 61e are provided at two positions spaced apart vertically on the edge on the right end 61a side, and a rectangular attachment piece 61c protrudes rearward between these holes. Is formed. Further, a protruding piece 61f protruding rearward is formed at a position closer to the inside of the tapered surface 61d.

  Further, a stopper receiving portion 64 is formed on the left end portion 61b side of the lumbar support main body 61 so as to protrude rearward along the vertical direction of the edge portion.

  A wide range from the vicinity of the right end portion 61a of the lumbar support main body 61 to the vicinity of the left end portion 61b is formed with the same thickness, and the above-described five slits 63a to 63e are provided therein. The strips 62a to 63f of the book are formed in parallel. Among the slits 63a to 63e, the upper slit 63a and the lower slit 63e are continuously provided with elongated holes 63a1 and 63e1 that are slightly wider in the vertical direction at positions near the left end 61b. . The long hole portions 63a1 and 63e1 function as guides by coming into contact with the outer periphery of an annular portion 71g provided in a support case 71 described later. Similarly, a long hole portion 63c1 that is slightly larger than the long hole portions 63a1 and 63e1 is continuously provided in the central slit 63c at a position near the left end portion 61b. It functions as a guide by coming into contact with the outer periphery of an annular portion 74a formed on a stopper member 74 described later.

  The support case 71 constituting the support part 70 is substantially box-shaped as described above, and an inverted U-shaped step part 71d is formed on the front surface of the plate part 71e constituting the bottom surface of the box with the same thickness in the front-rear direction. By forming, a case internal space Sc that can accommodate the left end 61 of the lumbar support main body 61 is formed inside these. A rectangular block-shaped slit guide 71f formed to the same thickness as the stepped portion 71d is formed on the right side of the case inner space Sc. The slit guide 71f is formed slightly smaller than the slits 63a to 63e of the lumbar support main body 61, and is disposed at a position corresponding to these, so that the lumbar support main body 61 is moved up and down via the inner edges of the slits 63a to 63e. It is possible to guide to restrain in the direction.

  In addition, two annular portions 71g described above are arranged on the front surface of the plate portion 71e, and are formed to have the same thickness as the stepped portion 71d. The annular portion 71g is used to attach a lid portion 72 described later, and as described above, is used to guide the long hole portions 63a1 and 63e1 provided in the slits 63a and 63e. A circular attachment hole 71 h is formed at a position slightly to the right of the center of the plate portion 71 e so that a small-diameter portion 73 a described later provided in the operation lever 73 can be inserted.

  Further, the support case 71 is substantially symmetrical with the back side of the left mounting end 71a in the drawing for mounting on the vertical rod 33B (see FIG. 11) with the back side of the right end 61a of the lumbar support main body 61 described above. It is in shape. That is, the back surface of the attachment end 71a is a tapered surface 71a1 along the flank 33c (see FIGS. 4 and 11) of the vertical rod 33B. In addition, screw insertion holes 71a2 and 71a2 are provided at two edges spaced apart from each other on the edge of the mounting end 71a, and a rectangular mounting piece 71b is formed so as to protrude rearward between them. ing. Furthermore, a protruding piece 71f protruding rearward is formed at a position closer to the inside of the tapered surface 71a1.

  The lid portion 72 attached to the support case 71 is a plate-like member having substantially the same outer shape as the stepped portion 71 d of the support case 71. The screw can be attached to the support case 71 by screwing a screw (not shown) into the central screw portion of the annular portion 71g provided in the support case 71 through the screw insertion holes 72a arranged above and below. . By attaching the lid 72 to the support case 71, these can cooperate to form a substantially flat surface. By doing so, unnecessary irregularities are avoided and the mesh ground 38 (see FIG. 1) is prevented from being caught or damaged.

  The support case 71 and the lid portion 72 constitute a support portion 70 that supports the left end portion 61b of the lumbar support main body 61 so as to be movable in the left-right direction within the range of the case internal space Sc.

  The support case 71 is provided with a stopper member 74 as a fixing portion that restricts the left-side end 61b of the lumbar support main body 61 from moving in the left-right direction. The stopper member 74 is formed as a cam having a substantially rectangular plate shape, and a small diameter portion 74a protruding in the normal direction is provided at a position slightly inward in the longitudinal direction from the center. In addition, each corner is cut into an arc shape so that the stopper member 74 can rotate in the case internal space Sc. The stopper member 74 locks a stopper receiving portion 64 provided at the left end portion 61b of the lumbar support main body 61, and constitutes a restricting means Mr between them.

  In addition, an operation lever 73 is disposed on the back side of the support case 71, and the small diameter portion 73a provided in the operation lever is inserted through the mounting hole 71h provided in the plate portion 71e described above. Then, a screw 75 is screwed into a screw hole provided at the center of the small diameter portion 73a of the operation lever 73 via a screw insertion hole 74b provided in the small diameter portion 74a of the stopper member 74, whereby the plate portion 71e is inserted. In a sandwiched state, the stopper member 74 and the operation lever 73 can be integrated, and by rotating the operation lever 73, the direction of the stopper member 74 can be changed. When the knob 73c of the operation lever 73 is turned sideways, the stopper member 74 is rotated so that the long side is in the horizontal direction and the knob 73c is in the vertical direction, so that the stopper member 74 has the long side in the vertical direction. Become.

  FIG. 14 is an enlarged view of the attachment portion 76 formed on the vertical rod 33B (33) for attaching the lumbar support 6. As shown in FIG. The other vertical rod 33A (see FIG. 11) is also formed with the vertical rod 33B symmetrically, and the mounting portion 76 having the same shape is formed. Therefore, as an example, the vertical rod 33B (33) will be described as an example.

  An attachment portion 76 is formed on the vertical rod 33 in a first region R1 (see FIG. 2) that is curved so as to protrude forward. Moreover, the attaching part 76 is formed in the escape region Rc vicinity in the vertical hook 33 mentioned above. The attachment portion 76 has a shape obtained by cutting out a part of the front surface 33a and the flank 33c visible from the front side of the vertical rod 33, that is, from the front, specifically, a part of the flank 33c and the front surface. A very small portion of 33a is retracted to form a vertically long plane portion 76a that is substantially perpendicular to the front-rear direction. Inside the flat surface portion 76a, a rectangular groove portion 76c having a long side direction in the vertical direction is formed. In addition, screw holes 76b and 76b are provided at two locations on the upper and lower sides of the flat portion 76a. The position of the attachment portion 76 is formed so as to extend upward from a position where the back frame 31 is widest in the left and right directions as viewed from the front (see FIG. 3). Therefore, it can be said that the mesh base 38 is widest and the point where the mesh ground 38 is easily bent, and the support effect by attaching the lumbar support 6 is easily obtained.

  14 will be described in more detail with reference to FIG. 13. When the support case 71 is attached to the vertical rod 33B side, the attachment portion 76 in which the back surface of the attachment end 71a of the support case 71 is formed on the vertical rod 33B. The flat portion 76B is supported so as to be in contact therewith. At this time, the attachment piece 71b engages with the groove 76c, so that the attachment piece 71b can be firmly supported in the left-right direction. Then, by screwing screws (not shown) into the screw holes 76b and 76b through the two screw insertion holes 72a and 72a, the support case 71 can be firmly fixed in the front-rear direction. . When the support case 71 is attached to the vertical rod 33 in this way, as shown in FIG. 15, the inner side (right side in the drawing) of the support case 71 is more rearward (upper side in the drawing) than the front surface 33a of the vertical rod 33. It is inclined to move backwards. For this reason, the lumbar support main body 61 supported by the support case 71 naturally curves in the center toward the rear, so that the waist can be supported more gently when seated.

  Referring to FIG. 14 again with reference to FIG. 13, the attachment structure of the right end 61a of the lumbar support main body 61 and the vertical rod 33A (see FIG. 11) will be described. As described above, the attachment portion 76 in FIG. 14 is symmetrical with the vertical rod 33B. First, the back surface of the right end portion 61 a of the lumbar support main body 61 is supported so as to abut on the flat surface portion 76 B of the mounting portion 76. At this time, the mounting piece 61c is engaged with the groove 76c, so that it can be firmly supported in the left-right direction. Then, screws (not shown) are screwed into the screw holes 76b and 76b through the two screw insertion holes 61e and 61e, so that the right end 61a of the lumbar support main body 61 is firmly attached in the front-rear direction. Can be fixed. When the support case 71 is attached to the vertical rod 33 in this manner, as in the case of the support case 71, as shown in FIG. It is inclined so as to recede toward the rear (upper side in the figure), and the center of the lumbar support main body 61 can be curved backward.

  With the mounting structure as described above, the lumbar support 6 can be mounted within the relief region Rc of the vertical rod 33. Therefore, the lumbar support 6 does not interfere with the mesh ground 38 and maintains the surface uniformity of the mesh ground 38 so as not to affect the appearance.

  The entire lumbar support 6 can be easily removed from the back frame 31 by removing screws (not shown) from the screw holes 76b, 76b provided in the left and right vertical rods 33. Therefore, the lumbar support 6 can be omitted depending on the user's preference. The attachment portion 76 is provided on the front side as described above, and is not conspicuous because it is usually hidden by the mesh ground 38.

  Since the lumbar support 6 is supported by the mesh ground 38, the position can be stabilized. Therefore, the lumbar support 6 cannot be fixed without inserting screws into the screw holes 76b, 76b provided in the left and right vertical rods 33. It will not be enough. Therefore, the lumbar support 6 can be attached later with the mesh ground 38 being carved. At this time, as described above, the entire vertical rod 33 is formed so as to extend in the direction orthogonal to the front surface 33a, that is, toward the rear, so that the rear of the mesh ground 38 is widely opened, The lumbar support 6 can be easily attached.

  Further, as shown in FIG. 16, when the lumbar support main body 61 is attached to the vertical rod 33A, the protruding piece 61f comes into contact with the inner side surface 33d of the vertical rod 33B. In this way, when the center of the lumbar support body 61 is bent so as to bend backward as the seated person leans against it, the projecting piece 61f tries to deform so as to spread outward, and this deformation is suppressed. A large pressing force is generated by being supported by the inner surface 33d. Therefore, the lumbar support main body 61 tries to return to the original shape by using the reaction force from the vertical rod 33B against the pressing force as a restoring force. Therefore, when the seated person leaves the seat, it can be easily restored and returned to the normal shape.

  A similar configuration is also provided on the support case 71 side as shown in FIG. 15, and the protruding piece 71 c comes into contact with the inner side surface 33 d of the vertical rod 33, thereby accompanying the bending of the lumbar support main body 61. Even if the support case 71 is deformed, the original position can be firmly restored.

  Here, based on FIG. 15, the effect | action of the support part 70 and the control means Mr is demonstrated. The support portion 70 is formed with a thin case inner space Sc in the front-rear direction, in which the left end 61b of the lumbar support main body 61 and the stopper member 74 are arranged in parallel. When a seated person leans down and the lumbar support main body 61 bends backward (upper side in the figure), the right end 61a (see FIG. 16) of the lumbar support main body 61 is fixed to the vertical rod 33. The left end 61b of the lumbar support main body 61 is displaced inward (rightward in the drawing) along the case internal space Sc. At this time, the stopper receiving portion 64 formed on the lumbar support main body 61 is locked to the stopper member 71 and the position is restricted, so that the bending amount is restricted so that the lumbar support main body 61 is not further deformed. .

  The case internal space Sc is formed with a dimension in the front-rear direction, that is, with a margin in the gap, so that the lumbar support main body 61 can move in the front-rear direction between the stopper member 74 and the inner surface 72 c of the lid portion 72. It has become. This dimension is preferably about 1 to 5 times the thickness of the center of the lumbar support body 61a. The left end portion 61b of the lumbar support main body 61 can be inclined rearward (upper side in the drawing) beyond the support case 71, and can be supported more flexibly by the amount of such movement in the front-rear direction. ing.

  In addition, when the lumbar support main body 61 is bent and a large inclination occurs, the left end 61b strongly contacts the inner surface 72c of the lid 72 and generates a pressing force. That is, the lid portion 72 functions as a regulating member that regulates the bending angle of the left end portion 61b, and can easily return to the original form by using the reaction force against the pressing force as a restoring force. Here, the bending angle of the left end 61b is an angle when the lumbar support main body 61 is bent and deformed, and is defined as a reference based on a free state to which no load is applied.

  FIGS. 17 and 19 illustrate how the amount of deformation that can be deformed is changed by operating the operation unit 73 to change the restriction amount of the lumbar support main body 61.

  FIG. 17A shows a state in which the lumbar support 6 is viewed from the rear, and the knob 73c of the operation unit 73 is positioned in the left-right direction. At this time, the stopper member 74 is in a state where the long side is directed in the left-right direction, and the distance m1 between the stopper member 74 and the stopper receiving portion 64 formed in the lumbar support main body 61 is relatively small. Therefore, the end portion 61b of the lumbar support main body 61 has a small movable distance, and is largely restricted. That is, it can be said that the end portion 61b of the lumbar support main body 61 is in a locked state. Note that m1 may be set to zero.

  FIG. 17B shows a cross section at the position V1-V1 in FIG. In a normal state where a load in the front-rear direction is not applied to the lumbar support main body 61, the lumbar support main body 61 is subjected to a force for restoring to a planar state by its own rigidity. One end portion 61b of the lumbar support main body 61 is supported via a support case 71 that is attached so as to be inclined at an attachment angle θ with respect to the left-right direction, and the other end portion 61a is also the same. Is supported directly on the vertical rod 33A at an angle of Therefore, even when the lumbar support main body 61 is in a state where the stopper receiving portion 64 is not in contact with the stopper member 74, the lumbar support main body 61 is in a curved state such that the vicinity of the center protrudes rearward.

  18 (a) and 18 (b) show a state in which a load directed backward is applied to the entire lumbar support main body 61 from this state. The lumbar support main body 61 as a whole tends to bend toward the rear so that the center protrudes further. However, since the distance m1 between the stopper receiving portion 64 and the stopper member 74 is small, the restriction is large, and the strip near the center in the vertical direction. The rearward displacement amount Δx11 at 62d (62c) is very small.

  At this time, although the tension in the left-right direction acts on the entire lumbar support main body 61, the restriction by the stopper member 74 acts on the strip 62d (62c) near the center in the vertical direction and is positioned above and below these. Since the strips 62a, 62b, 62e, and 62f are not directly restricted by the stopper member 74, the upper and lower ends 64a and 64b of the stopper receiving portion 64 are deformed so as to be displaced inward. In other words, the peripheral portions of the strips 62a, 62b, 62e, and 62f move in the left-right direction while undergoing elastic deformation as a deformation allowing portion Be (see FIG. 21) described later.

  Therefore, compared to the strips 62c and 62d near the center in the vertical direction, the strips 62b and 62e positioned above and below can bend further rearward, and the strips 62a and 62f positioned at the upper and lower ends are further rearward. It is possible to bend toward. FIG. 18B is a comparison of the bending shapes of the strip 62d near the center in the vertical direction and the strip 62f at the lowermost end, and the strip 62f at the lowermost end has a larger displacement amount Δx12 than the strip 62d. Can be obtained. From this, the lumbar support 6 of the present embodiment sets the vertical center as a specific position in the vertical direction for more firmly supporting the seated person's waist, and the strips 62c, 62d at this position While reducing the flexibility, the strips 62a, 62b, 62e, and 62f that are further away from each other in the vertical direction increase the flexibility and follow the deformation of the strips 62c and 62d near the center. It can be said that it can be appropriately deformed according to the external force.

  Here, FIGS. 21A and 21B show end views at the P1-P1 position in FIG. 17A and the P-P2 position in FIG. 18A, respectively. As shown in FIG. 21A, the strips 62a to 62f constituting the lumbar support main body 61 have a shape slightly curved along the curvature of the first region R1 (see FIG. 2) on the back surface of the mesh ground 38. It is arranged to be. In addition, each strip 62a to 62f has a curved shape that protrudes to the front side, and each cross section has an edge portion so that it can softly contact the body of the seated person via the mesh ground 38. It is processed so that it is smoothly continuous by a curve.

  As shown in FIG. 21 (b), when a load is applied to the entire lumbar support main body 61 from the front side, the strips 62c and 62d near the center in the vertical direction bend substantially backward as described above. There is no. On the other hand, the strips 62b and 62e positioned above and below, and the strips 62a and 62f positioned further above and below can be gradually bent backward gradually. Further, as shown in the drawing, each of the strips 62a to 62f can be twisted and deformed along with the backward deflection. This is due to the fact that the strips 62a to 62f are formed in a strip-like shape having a width, and a structure that enables bending, which will be described in detail later. In addition, as described above, the fact that the elastic deformation can be allowed by being formed of a resin material such as polypropylene also contributes to the enhancement of the effect. In this way, the upper and lower strips 62a, 62b, 62e, and 62f are twisted and deformed while rearwardly deforming, so that the lumbar support body 61 is deformed smoothly as a whole following the mesh ground 38. It is possible to avoid the mesh ground 38 from being bent extremely at the positions of the strips 62a and 62f. Therefore, the body of the seated person can be supported more appropriately, and damage to the mesh ground 38 due to sliding contact with the lumbar support 6 can be suppressed.

  The above operation example is a case where a substantially uniform force is applied to the lumbar support main body 61 in the vertical direction. When an extremely large force is applied to the upper side from the lower side, the upper side is conversely higher than the upper side. When an extremely large force is applied to the lower side, it behaves differently. That is, when a force is applied exclusively to the upper strips 62a and 62b, the upper strips 62a and 62b are displaced rearward with the vicinity of the center in the vertical direction regulated by the stopper member 74 as a large force. The lower strips 62e and 62f are displaced forward. Further, when a force is applied exclusively to the lower strips 62e and 62f, the lower strips 62e and 62f are displaced rearward, while the upper strips 62a and 62b are displaced forward. . For this reason, when the seated person's waist is in contact with the lumbar support body 61, the lumbar support body 61 can change the position more appropriately and support the entire seated person's waist.

  FIG. 19A shows a state in which the knob 73c of the operation unit 73 is rotated to a downward position from the state of FIG. At this time, the stopper member 74 has a long side in the vertical direction and a short side in the horizontal direction. By doing so, the distance m2 from the stopper receiving portion 64 formed in the lumbar support main body 61 is increased. That is, the end portion 61b of the lumbar support main body 61 has a longer movable distance and a smaller restriction. That is, it can be said that the end portion 61b of the lumbar support main body 61 is in an unlocked state. However, even in this case, unless a load in the front-rear direction is applied to the lumbar support main body 61, the lumbar support main body 61 remains in its original position by its own rigidity as shown in FIG. Become.

  20A and 20B show a state in which a load directed backward is applied to the entire lumbar support main body 61 from this state. As shown in FIG. 20 (b), the lumbar support main body 61 can be greatly bent rearward as compared with the case of FIG. 18 (b), and the bending in the strip 62d (62c) near the center in the vertical direction is possible. Both the amount Δx21 and the deflection amount Δx22 of the upper and lower strips 62f (62a) can be larger than the initial deflection amounts Δx11, Δx12 (see FIG. 18). By doing so, it is possible to reduce the regulation of the waist by the lumbar support 6. Also in this case, the relationship between the strips 62a to 62f arranged above and below is the same, and it is possible to appropriately support the seated person's waist by adjusting the positional relationship with each other.

  Further, since the regulating means Mr for regulating the amount of deflection of the lumbar support main body 61 is provided on the vertical rod 33B via the support portion 70, the lumbar support main body 61 bends substantially the entire left and right direction. It is possible to support the waist of the seated person in a wider range, and it is possible to improve comfort. Further, since the operation lever 73 for changing the amount of bending is similarly provided on the vertical rod 33B via the support portion 70, if the seated person extends his / her hand back while sitting, The operation can be easily performed, and it is possible to set the deflection amount according to the preference. In addition, the operation lever 73 can be operated by rotating the knob 73c so that the position of the knob 73c is changed between the inwardly facing state and the downwardly facing state. It can be said that it has.

  Furthermore, since the entire support portion 70 including the operation lever 73 and the restricting means Mr is provided at the end portion, coupled with the structure in which the mesh ground 38 (see FIG. 1) is attached to the back frame 31, When viewed, the area through which light passes is increased to give a sense of openness. Furthermore, since the support part 70 has a left-right asymmetric structure provided only on one vertical rod 33B (see FIG. 11), this is a structure that can be easily discriminated through the mesh ground 38. It is possible to present a characteristic appearance that gives a more sophisticated impression.

  In addition, the lumbar support main body 61 in the present embodiment has a characteristic shape in which six strips 62a to 62f are arranged in parallel in the vertical direction, as shown in FIG. Hereinafter, the operation obtained by such a shape will be described.

  When the lumbar support main body 61 is viewed in detail, it can be seen that the strips 62a to 62f are sequentially connected by connecting portions 65a to 65f extending in the vertical direction. FIG. 21B schematically shows the lumbar support main body 61 separated into parts in the vertical direction. Each strip 62a-62f functions as a body support part Bs for holding the body.

  Considering the two strips 62c and 62d in the central portion, since the strip members 62c and 62d have stopper members 74 (see FIGS. 17 and 19) in the extending direction, The tension (arrow in the figure) generated by leaning acts in substantially the same direction as the extending direction. Therefore, the strips 62c and 62d are uniformly deformed according to the cross-sectional shape for holding the body as a whole, and can be bent evenly.

  On the other hand, it can be considered that the strips 62b and 62e arranged above and below the strips 62c and 62d are respectively connected to the strips 62c and 62d via the connection portions 65b and 65e. . And it is thought that the tension (arrow in the figure) generated by the seated person leaning on as described above acts near the center, that is, the lower end of the connecting portion 65b or the upper end of the connecting portion 65e. Then, it does not act directly on the strips 62c and 62d constituting the body support part Bs, but acts around the connecting parts 65b and 65e. Therefore, the connecting portions 65b and 65e function as arm portions orthogonal to the expansion / contraction direction, thereby acting as a deformation allowing portion Be, and allowing expansion / contraction in the left / right direction, that is, position change with respect to the central strips 62c and 62d. can do. By doing so, the upper and lower strips 62b and 62e change the position in the left-right direction as if they were expanded and contracted together with the connecting portions 65b and 65e with respect to the central strips 62c and 62d. The body can be held.

  Similarly, the strips 62a and 62f arranged further above and below the strips 62b and 62e are connected to the central strips 62c and 62d via the connection portions 65a and 65b or the connection portions 65e and 65f, respectively. Can be seen. That is, it can be said that the larger deformation | transformation tolerance part Be which functions as an arm part orthogonal to the expansion-contraction direction which consists of connection part 65a, 65b or connection part 65e, 65f is provided. Therefore, the central strips 62c and 62d can be allowed to expand or contract in the left-right direction, that is, change in position.

  As described above, among the strips 62a to 62f, it can be said that the strips 62a, 62b, 62e, and 62f are provided with the deformation-permitting portions Be. It is possible for the whole body to support the body more stably by acting so that the whole supports the body widely without supporting the body.

  The lumbar support 6 in this embodiment does not have a slide mechanism that slides up and down to change the position along the body, but is relatively small in flexibility so that the body can be firmly supported. The strips 62a, 61b, 61e, 61f having relatively large flexibility by having the deformation-allowing portion Be at the end adjacent to the strips 61c, 61d positioned in the center in the vertical direction. By being provided, it is possible to obtain a more natural feeling of use by appropriately deforming along the body.

  As described above, the chair according to this embodiment includes a pair of vertical rods 33 and 33 that constitute a part of the back frame 31 and a mesh that is a tension member stretched between the vertical rods 33 and 33. Comprising a ground 38 and a lumbar support 6 disposed in the range of the middle portion of the mesh ground 38 in the vertical direction on the back side of the mesh ground 38 and having both ends attached to the vertical rods 33, 33, The support 6 includes six strips 62a to 62f that extend in the left-right direction and are arranged in parallel in the vertical direction, and the strips 62c and 62d that are located at the center in the vertical direction, which is a specific position in the vertical direction. Compared to the above, the strips 62a, 62b, 62e, 62f at positions separated in the upward or downward direction are configured to have greater flexibility.

  With this configuration, the strips 62c and 62d located in the central portion in the vertical direction are relatively small in flexibility, so that the seated person can lean against the back and the mesh ground 38 bends backward. In this case, it is possible to support the lumbar part firmly and to function effectively as the lumbar support 6. Further, since the strips 62a, 62b, 62e, 62f located at positions above or below the strips 62c, 62d located at the central portion in the vertical direction are relatively flexible, the vertical direction The lumbar support 6 is bent so as to be shaped along the waist while centering on the strips 62c and 62d at the center, so that the entire lumbar support 6 does not cause a burden on a part of the waist, and the waist It is possible to support the whole. Further, even if the mesh ground 38 is greatly bent at a position where the lumbar support 6 is not on the back surface, the upper and lower end portions of the lumbar support 6 are deformed to prevent the mesh ground 38 from being greatly bent at the boundary portion. The sliding resistance with the support 6 can be reduced to prevent the tension member from being damaged.

  And the deformation | transformation permission part Be for producing a bending is provided in the edge part of the strips 62a, 62b, 62e, and 62f of the position distant from the strips 62c and 62d located in the center part of an up-down direction. With this configuration, the strips 62a, 62b, 62e, and 62f can be made to have great flexibility by the deformation allowing portion Be, and the deformation allowing portion Be is at the end. The middle part in the left-right direction where the lower back part abuts more strongly can have a solid structure that supports the body as the body support part Bs, and the discomfort that the seated person feels due to the deformation of the deformation-allowing part Be accompanying the bending. It is also possible to make it smaller.

  Further, the end of the strips 62a, 62b, 62e, 62f at the position where the deformation allowing portion Be is taken out in the vertical direction from the end portions of the strips 62c, 62d located in the central portion in the vertical direction and separated upward or downward. Since the connecting portions 65a, 65b, 65e, and 65f function as arm portions connected to the portions, the flexibility of the strips 62a, 62b, 62e, and 62f can be set in the vertical center portion with a simple configuration. It is possible to make it larger than the strips 62c and 62d located in the area.

  Further, since the stopper member 74, which is a fixed portion for restricting the bending of the strips 62a to 62f, is configured to be provided in the vicinity of the end portions of the strips 62c and 62d located in the vertical center portion, The stopper member 74 can effectively suppress the bending of the strips 62c and 62d positioned in the center in the vertical direction, and can reduce the influence on the bending of the strips 62a and 62f in the vicinity of the vertical end portion to reduce the vertical direction. It is possible to easily make a difference in the flexibility of the strips 62a to 62f arranged on the belt.

  Further, the stopper member 74 regulates the movement of the end portions of the strips 62c and 62d located at the central portion in the vertical direction, and the strip 62c and the strip 62c located at the central portion in the vertical direction by changing the regulation amount. Since the flexibility of 62d can be changed, it is possible to greatly change the support strength of the waist by the lumbar support 6 as a whole according to the preference of the seated person.

  Then, the strips at a specific position in the vertical direction that make the flexibility relatively small are set as the strips 62c and 62d located in the central portion in the vertical direction, and the strips 62c and 62d are adjacent to each other in the vertical direction. Since the strips 62b and 62d are provided and the flexibility of the strips 62b and 62d is relatively large, the contact pressure to the body at the upper and lower edges of the lumbar support 6 is weakened, and the pressure is partially applied. It is designed not to be excessive.

  The vertical rods 33, 33 are provided with a front surface 33 a as a support surface for supporting the mesh ground 38 at the front portion, and gradually escape from the mesh ground 33 a toward the inner side of the front surface 33 a toward the inner side. Since Rc is formed and the lumbar support 6 is configured to be attached to the relief region Rc of the vertical rods 33, 33, the lumbar support 6 is meshed by being attached to the relief region Rc of the vertical rods 33, 33. Interference with the ground 38 can be easily avoided, and it is possible to obtain a good appearance while maintaining the uniformity of the mesh ground 38.

  Further, when the above configuration is viewed from another point of view, when the lumbar support main body 61 including the plurality of strips 33a to 33f is captured as one strip, the chair according to the present embodiment is a part of the back frame 31. A pair of vertical rods 33, 33, a mesh ground 38 that is a tension member stretched between the vertical rods 33, 33, and the middle of the mesh ground 38 in the vertical direction on the back side of the mesh ground 38. The lumbar support 6 is arranged in the range of the portion, and the lumbar support 6 has both ends attached to the vertical rods 33, 33. The lumbar support 6 is for the upper and lower edges to bend following the bending of the mesh ground 38. It can be said that it has a structure and is configured such that the flexibility becomes smaller toward the center in the vertical direction.

  With this configuration, the flexibility of the central portion in the vertical direction of the lumbar support 6 is relatively small, so that when the seated person rests on the back and the mesh ground 38 bends backward, the waist portion The lumbar support 6 can function effectively. Furthermore, since the upper and lower end portions have a relatively large flexibility, the entire lumbar support 6 does not cause a burden on a part of the lumbar portion by flexing to form a shape along the lumbar portion. It becomes a form and it is possible to support the whole waist | hip | lumbar part appropriately.

  The specific configuration of each unit is not limited to the above-described embodiment.

  For example, in the above-described embodiment, the mesh ground 38 is used as the tension material. However, as long as it has elasticity that can be stretched on the frame body, the woven fabric, the nonwoven fabric, the film, and the like are not limited thereto. The sheet-like material can be used effectively.

  In the above-described embodiment, the lumbar support main body 61 is configured to include the six strips 62a to 62f. However, if the upper and lower strips are deformed following the central one, the same effect as described above can be obtained. Therefore, in the case of using strips, it is possible to adopt a configuration in which three strips are arranged up and down.

  Further, as shown in FIGS. 23 and 24, the lumbar support main body 161 and the periphery of the attachment portion 176 of the vertical rod 133 can be modified. The lumbar support main body 161 has five strips 162a to 162e extending in the left-right direction arranged in parallel in the vertical direction, and the end portions of the strips 162b to 162d near the center are connected to the back side. A stopper receiving portion 164 is formed on the surface. Further, the upper and lower strips 162a and 162e are provided with an elastic bent portion 166 having a reverse V-shape in plan view protruding in the front-rear direction (backward direction in this example), and the end portions are connected to each other through a thin plate shape. It connects by the part 165, the back surface is made to contact | abut to the plane part 176a with which the attachment part 176 of the vertical shaft 133 is equipped, and it fixes using the screw penetration hole 165a and the screw hole 176b. The elastic bending portion 166 has a large expansion / contraction function like a spring, and can function as the above-described deformation allowing portion Be. An overhanging portion 177 is formed inwardly on the vertical rod 133, and the small-diameter portion 173a of the operating lever 173 and the stopper member 174 use the screw hole 173b through the insertion hole 177a provided therein. And can be fixed. The stopper member 174 has a long side direction and a short side direction. By changing the position of the knob 173c of the operation lever 173, the direction of the stopper member 164 is changed to change the amount of restriction of the stopper receiving portion 164, whereby the lumbar support body 161 is changed. Can be controlled. Of the five strips 162a to 162e, the upper and lower 162a, 162e are provided with elastic bending portions 166 (deformation allowance portions Be) so that the entire lumbar support body 161 supports the body widely. It has become. In other words, since the deformation allowing portion Be is integrally formed with the strips 162a and 162e as the elastic bent portion 166 protruding in a direction substantially orthogonal to the spine 3, the expansion and contraction in the left-right direction can be set large. It is possible to obtain a high waist support performance by changing to a more appropriate shape between the other strips 162b to 162d.

  Also, the structure of FIGS. 23 and 24 can be further simplified and modified as shown in FIG. In this example, the lumbar support main body 261 is configured by three strips 262a to 262c extending in the left-right direction, and the upper and lower strips 262a, 262c have elastic bent portions 266 (deformation allowance portions Be at the ends). ) And is further connected by a connection portion 265. The connecting portion 265 is provided with a screw hole 265a, which can be connected to the vertical rod 33 (see FIG. 11). The central strip 262b can change the amount of regulation of the central strip 262b by operating a buckle 273 that is an operation unit. Specifically, the buckle 273 is rotatably attached by a fulcrum 265b provided at the connection portion 265, and the end 262b1 of the strip 262b is supported by the action point 273b provided at a position slightly away from the fulcrum. Has been. Further, the tip of the buckle 273 is configured as a force point 273c for operation. When the tip of the buckle 273 is directed to the left side in the figure, the restriction of the strip 262b is reduced and the tip of the buckle 273 is shown in the figure. When it is directed to the right side, the strip 262b is pulled in the right direction so that the regulation can be greatly exerted. Further, since the upper and lower strips 262a and 262c are provided with elastic bent portions 166 (deformation allowing portions Be) at their ends, the positions can be adjusted to support the body widely.

  Also, the lumbar support body 361A can be configured based on the above-described lumbar support body 61 (see FIG. 17) and modified as shown in FIG. The lumbar support main body 361A is formed by connecting the ends of strips 362a to 362f extending in the left-right direction by connecting portions 365 and 365. A slit 363a is provided between the strips 362a to 362f. -363e are formed, and each strip 362a-362f can be bent independently. Attachment pieces 366A and 366A are formed at the center in the vertical direction of each connection portion 365 and 365, and are directly attached to the vertical rods 33 and 33 (see FIG. 11) using this. That is, in this embodiment, there is no structure for changing the amount of restriction of bending by the stopper member 74 (see FIG. 17). However, the attachment pieces 366A, 366A function as a fixing portion for restricting the bending of the strips 362c, 362d located in the central portion in the vertical direction, and the strips 363a, 363b, 363d, 363e positioned above and below are fixed. Since the connecting portion functions as an arm portion, it has greater flexibility than the strips 362c and 362d located in the central portion in the vertical direction. Even if comprised in this way, the effect according to embodiment mentioned above can be acquired, and a seated person's whole waist | hip | lumbar part can be suitably supported by deform | transforming the whole along a seated person's waist | hip | lumbar part.

  Furthermore, the lumbar support main body 361B can be configured by being modified as shown in FIG. This is based on the lumbar support 361A shown in FIG. 26A and is provided near the lower end by changing the position of the mounting piece 366B. In this case, the attachment pieces 366B and 366B function as a fixing portion that regulates the two strips 362e and 362f near the lower end. That is, a specific position in the vertical direction for more firmly supporting the seated person's waist is set as a position near the lower end of the lumbar support main body 361B, and the flexibility of the strips 362e and 362f at this position is relatively small. . And the strip 362a-362d of the position away from this upward is provided with comparatively big flexibility because the connection part 365 functions as an arm part. Even when configured in this way, the effect according to the above-described embodiment can be obtained, and the lower part of the waist of the seated person is firmly supported and the whole is deformed so as to be curved starting from this position. Similarly to the above, it is possible to favorably support the entire waist of the seated person.

  Further, the lumbar support main body 461 can be configured based on the above-described lumbar support main body 61 (see FIG. 17) and modified as shown in FIG. This lumbar support main body 461 is formed by connecting the ends of strips 462a to 462f extending in the left-right direction by connecting portions 465a and 465f. Between these strips 462a to 462f, there is a slit 463a. ˜463e are formed, and the strips 462a to 462f can be bent independently. Of these slits 463a to 463e, the central slit 463c is formed to have the smallest width and increase in width in the vertical direction. For this reason, the strips 462a to 462f are positioned at the central portion in the vertical direction. The widths of the strips 462c and 462d are larger, and the width becomes smaller as the strips 462a and 462f at the upper and lower ends are formed. Accordingly, the strips 462a and 462f positioned at the top and bottom are easily stretched by applying a load, and the flexibility is increased. The lumbar support body 461 having such a configuration can also favorably support the seated person's waist.

  Similarly, a lumbar support main body 561 as shown in FIG. In this case, end portions of the strips 562a to 562f extending in the left-right direction are connected by connecting portions 565 and 565. Slits 563a to 563e are formed between the strips 562a to 562f, and the strips 562a to 562f can be bent independently. The strips 562c and 562d positioned at the central portion in the vertical direction are formed with substantially the same width in the longitudinal direction, whereas the strips 562b and 562e positioned above and below the central portions 562b1 and 562e1 in the longitudinal direction. The strips 562c and 562d are formed with the same width, and the longitudinal ends 562b2 and 562e2 are formed with a smaller width. Further, the strips 562a and 562f located at the upper and lower end portions have longitudinal center portions 562a1 and 562f1 formed in the same width as the strips 562c and 562d, and the longitudinal end portions 562a2 and 562f2 are strip strips 562b and 562b. It is formed with a smaller width than end portions 562b2 and 562e2 of 562e. As described above, the strips 562a to 562f are formed such that the end portions are formed with a smaller width in the vertical direction, so that the flexibility is increased. The lumbar support body 561 having such a configuration can also favorably support the seated person's waist.

  Further, as described above, even if the lumbar support body 61 (see FIG. 17) does not include a plurality of strips 61a to 61f, the upper and lower edges are bent and deformed according to the center. An effect can be obtained. Specifically, as shown in FIG. 28A, the lumbar support main body 661 may be formed in a single band shape, and a plurality of cuts 662 to 662 may be provided in parallel along the upper and lower edges. If it carries out like this, flexibility can be enlarged by reducing the rigidity of an up-and-down edge part. The lumbar support body 661 having such a configuration can also favorably support the seated person's waist.

  Similarly, as shown in FIG. 28 (b), the lumbar support main body 761A may be formed in a single band shape and may be formed so as to penetrate a large number of small holes 762A throughout the thickness direction. . The small holes 762A are regularly formed at equal pitches in the upper, lower, left, and right sides, and the diameter is smaller at the central part in the vertical direction, and the diameter is increased as it goes up and down. It can be reduced and flexibility can be increased. The lumbar support body 761A having such a configuration can favorably support the seated person's waist.

  Also, based on this form, as shown in FIG. 29 (a), a number of small holes 762B provided over the entire lumbar support main body 761B have the same diameter, and pitches in the left-right direction as going up and down. May be formed to be small and to have a high density. Also by doing this, the rigidity can be gradually reduced and the flexibility can be increased as the upper and lower edges are approached, and the waist of the seated person can be suitably supported.

  Further, a mesh structure 862 can be used instead of the mode using the small holes 762A (see FIG. 28) and the small holes 762B. By making the mesh structure 862 finer at the center in the vertical direction and becoming coarser as it goes up and down, the rigidity can be gradually reduced and the flexibility can be increased as it approaches the upper and lower edges. The seated person's waist can be supported.

  Further, as shown in FIG. 30, the cross section of the lumbar support main body 961 may be thick at the central portion in the vertical direction and thin as it approaches the vertical edge portions 963 and 964. Also by doing this, the rigidity can be gradually reduced and the flexibility can be increased as the upper and lower edges are approached, and the waist of the seated person can be suitably supported.

  Other configurations can be variously modified without departing from the spirit of the present invention.

6 ... Lumbar support 31 ... Back frame 33 ... Vertical rod 33a ... Front (support surface)
38 ... Mesh (tension)
61 ... Lumber support main body 62, 62a to 62f ... Strips 65a, 65b, 65e, 65f ... Connection part (arm part)
65c, 65d ... connection part (arm part)
74: Stopper member (fixed part)
Rc ... Escape area Be ... Deformation allowable part

That is, the chair of the present invention includes a pair of vertical eaves constituting a part of the back frame, a tension member stretched between these vertical eaves, and a vertical direction of the tension member on the back side of the tension member A lumbar support that is arranged in a range of an intermediate portion and has both ends attached to the vertical shaft, wherein the lumbar support is formed in one band shape, and a plurality of lumbar supports along the upper and lower edges. A lumbar support main body provided with incisions in parallel is provided.
If comprised in this way, flexibility can be enlarged by reducing the rigidity of an up-and-down edge part, and a seated person's waist | hip | lumbar part can be supported suitably.

  The chair of the present invention includes a pair of vertical eaves constituting a part of the back frame, a tension member stretched between these vertical eaves, and a vertical intermediate portion of the tension member on the back side of the tension member And a lumbar support attached to both ends of the vertical shaft, wherein the lumbar support is formed in a single band shape and has a large number of small holes throughout. The lumbar support main body is formed so as to penetrate in the direction, and the small holes are regularly formed at equal pitches in the upper, lower, left, and right directions, and the diameter is smaller at the central part in the vertical direction, and the diameter increases as it goes up and down And
  If comprised in this way, a rigidity can be gradually reduced and flexibility can be enlarged as it approaches an up-and-down edge part, and a seated person's waist | hip | lumbar part can be supported suitably.

  The chair of the present invention includes a pair of vertical eaves constituting a part of the back frame, a tension member stretched between these vertical eaves, and a vertical intermediate portion of the tension member on the back side of the tension member And a lumbar support attached to both ends of the vertical shaft, wherein the lumbar support is formed in a single band shape and has a large number of small holes throughout. The lumbar support main body is formed so as to penetrate in the direction, and the plurality of small holes have the same diameter, and the pitch is reduced in the left-right direction and the density is increased as it goes up and down. To do.
  If comprised in this way, a rigidity can be gradually reduced and flexibility can be enlarged as it approaches an up-and-down edge part, and a seated person's waist | hip | lumbar part can be supported suitably.

  The chair of the present invention includes a pair of vertical eaves constituting a part of the back frame, a tension member stretched between these vertical eaves, and a vertical intermediate portion of the tension member on the back side of the tension member And a lumbar support having both ends attached to the vertical shaft, the lumbar support being formed in a single band shape and a mesh structure throughout. A support body is provided, and the mesh structure is finer at the center in the vertical direction, and is coarser as it goes up and down.
  If comprised in this way, a rigidity can be gradually reduced and flexibility can be enlarged as it approaches an up-and-down edge part, and a seated person's waist | hip | lumbar part can be supported suitably.

  The chair of the present invention includes a pair of vertical eaves constituting a part of the back frame, a tension member stretched between these vertical eaves, and a vertical intermediate portion of the tension member on the back side of the tension member And a lumbar support attached to both ends of the vertical shaft, wherein the lumbar support is formed in one band shape and is thick at the center in the vertical direction, and the upper and lower edges. And a lumbar support body having a cross section that becomes thinner as it approaches.
  If comprised in this way, a rigidity can be gradually reduced and flexibility can be enlarged as it approaches an up-and-down edge part, and a seated person's waist | hip | lumbar part can be supported suitably.

  The chair of the present invention includes a pair of vertical eaves constituting a part of the back frame, a tension member stretched between these vertical eaves, and a vertical intermediate portion of the tension member on the back side of the tension member The lumbar support is provided with a lumbar support that is attached to both ends of the downspout, and the lumbar support includes a lumbar support main body that is attached to the downspread throughout the entire area. The lumbar support main body has a structure in which the upper and lower edges of the lumbar support body are bent to follow the bending of the tension member, and is configured to be less flexible as it goes to the center in the vertical direction.
  If comprised in this way, the whole waist | hip | lumbar part can be appropriately supported by a lumbar support.

Claims (8)

A pair of vertical eaves constituting a part of the back frame, a tension member stretched between these vertical eaves, and arranged in the range of the intermediate portion in the vertical direction of the tension material on the back side of the tension material, A lumbar support having both ends attached to the downspout,
The lumbar support includes at least three strips extending in the left-right direction and arranged in parallel in the up-down direction,
A chair configured to increase the flexibility of the strip at a position separated upward or downward from the strip at a specific position in the vertical direction.   The chair according to claim 1, further comprising a deformation allowing portion for causing bending at an end portion in the left-right direction of the strip.   The deformation allowing portion is an arm portion that is taken up in the vertical direction from the end portion of the strip at a specific position in the vertical direction and connected to the end portion of the strip in a position separated upward or downward. The chair according to claim 2.   The chair according to any one of claims 1 to 3, wherein a fixing portion for restricting the bending of the strip is provided in the vicinity of an end portion of the strip at a specific position in the vertical direction.   The fixing portion regulates the movement of the end of the strip at the specific position in the vertical direction, and the flexibility of the strip at the specific position in the vertical direction can be changed by changing the regulation amount. The chair according to claim 4, which is configured as follows.   The strip in a specific position in the vertical direction is a strip located in a central portion in the vertical direction, and different strips are provided adjacent to the vertical direction of the strip. A chair according to any one of the above.   The vertical rod is provided with a support surface for supporting the tension member at the front portion, and is formed with a relief region that gradually separates from the tension member toward the inside at a position inside the support surface, The lumbar support is attached to the escape area of the downspout, The chair according to any one of claims 1 to 6 characterized by things. A pair of vertical eaves constituting a part of the back frame, a tension member stretched between these vertical eaves, and arranged in the range of the intermediate portion in the vertical direction of the tension material on the back side of the tension material, A lumbar support having both ends attached to the downspout,
The lumbar support has a structure in which the upper and lower edge portions are bent to follow the bending of the upholstery material, and is configured so that the flexibility becomes smaller toward the vertical center portion. .

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