JP5712370B2 - Chair - Google Patents

Description

  The present invention relates to a chair used in an office or the like.

  This type of office (or office) chair is often accompanied by an armrest. When an armrest is provided on a chair, an elbow strut extending upward from a support base arranged at the upper end of the leg strut is set up, and an elbow rest is supported on the elbow strut, or a back support arm that is attached to the support base in a tiltable manner. In many cases, the elbow support portion extending in the front-rear direction is fixed and the elbow support portion supports the elbow rest.

  The chair disclosed in Patent Document 1 below is an example of the latter. In what takes this aspect, it is exclusively that the back support arm (reference numeral 13 in the figure) and the elbow support part (reference numeral 5 in the figure) are separate members. Therefore, in assembling the chair, a process of fixing the elbow support to the back support arm is essential, which is disadvantageous in terms of work man-hours.

  In addition, in what takes this aspect, it is possible to design so that the external appearance and thickness of an elbow support part may be equal to that of a back support arm. However, if the elbow support is made as thick as the back support arm, which is required to be strong, the armrest will increase in weight.

Japanese Patent Laying-Open No. 2005-073872

  The main object of the present invention is to avoid the weight of the armrest while simplifying the assembling work of the chair provided with the armrest.

In the present invention, in a chair provided with a pair of back support arms on the left and right sides of the backrest and provided with an armrest extending in the front-rear direction at a portion extending vertically in each back support arm, a cavity is formed in the armrest Then , the internal space of the armrest wrap is made to reach a part extending in the vertical direction of the back support arm, and a cavity communicating with the internal space is formed in the part . In addition, in the present invention, in a chair provided with a pair of back support arms on the left and right sides of the backrest, and provided with armrests extending in the front-rear direction at a portion extending in the vertical direction in each back support arm, a hollow is formed inside the armrest. The elbow support includes an elbow support having an inner space opened upward as a component of the armrest, and a member serving as a lid that closes the opening of the elbow support from above, the elbow support An operation part for operating a predetermined function of the chair and a transmission member or a transmission mechanism for transmitting an operation force applied to the operation part are housed on the side of the chair, and the lid body forms the uppermost surface of the armrest. The lid is a single member expanded to a size extending from the elbow support to the upper end of the back support arm.

  When the elbow support includes an elbow support part having an internal space opened upward and a member serving as a lid that closes the opening of the elbow support part from above, On the side, an operation unit for operating a predetermined function of the chair, and a transmission member or a transmission mechanism that transmits an operation force applied to the operation unit can be accommodated.

  The inner space of the elbow support section preferably extends over substantially the entire area of the front and rear dimensions of the elbow support section, and the lid that closes the opening of the elbow support section also preferably covers the entire area of the opening. .

  If the inner space of the elbow support part reaches a part extending in the vertical direction of the back support arm and a cavity communicating with the inner space is formed in the part, the weight of the armrest is further reduced. Contribute to

  By inserting a transmission member or a transmission mechanism for transmitting an operation force applied to an operation unit for operating a predetermined function of the chair into the cavity formed in a portion extending in the vertical direction of the back support arm, By guiding downward from the internal space of the support portion along the portion extending in the vertical direction of the back support arm, the back support arm can suitably conceal the transmission member or transmission mechanism without exposing it to the public. It becomes possible.

  If the lid body forms the uppermost surface of the armrest, and this lid body is a single member expanded to a size extending from the elbow support portion to the upper end portion of the back support arm, The lid can be easily attached to and detached from the elbow support.

  ADVANTAGE OF THE INVENTION According to this invention, the weight increase of an armrest can be avoided, aiming at the simplification of the assembly operation | work of the chair which provides an armrest.

The perspective view from the front which shows one Embodiment of this invention. The perspective view from the front which decomposes | disassembles and shows the tension ground of the embodiment. The front which abbreviate | omits and shows the tension place of the embodiment partially. The left view which decomposes | disassembles and shows the tension ground of the embodiment. The rear view which abbreviate | omits and shows the tension place of the embodiment partially. The perspective view from the back which abbreviate | omits and shows the leg of the embodiment. The disassembled perspective view which abbreviate | omits and shows a part of the whole embodiment. The perspective view from the front which expands and shows the principal part of the support base and back support arm of the embodiment. The disassembled perspective view which expands and shows the principal part of the support base of the same embodiment, and a back support arm. The perspective view from the back which abbreviate | omits and shows the support base part of the embodiment abbreviate | omitting. The front view which decomposes | disassembles and shows the support base part of the embodiment. The left view which shows the support base and seat of the embodiment. Explanatory drawing equivalent to FIG. 12 which shows the locking mechanism of the embodiment. The disassembled perspective view which shows the seat and seat receiver of the embodiment. Sectional view on the AA line which showed the principal part in FIG. BB sectional drawing which showed the principal part in FIG. CC sectional view which showed the principal part in FIG. The perspective view which showed the attachment structure of the backrest support body and back support member of the embodiment. The perspective view which decomposes | disassembles and shows the back shell and back support member of the embodiment. The front view of the back shell of the embodiment. The front view of the back support member of the embodiment. DD line sectional drawing which showed the principal part in FIG. EE sectional view which showed the principal part in FIG. The FF line expanded sectional view in FIG. The GG sectional view taken on the line in FIG. The HH sectional view taken on the line which showed the principal part in FIG. FIG. 4 is a cross-sectional view taken along a line II, showing a part of the main part in FIG. The left view which shows the right back support arm and elbow support part seeing from the seated person of the embodiment. The perspective view which decomposes | disassembles and shows the elbow support part and elbow rest of the embodiment. The perspective view from the back which shows the attachment base of the elbow rest of the embodiment. The sectional side view which shows the elbow support part and elbow rest of the embodiment. The front sectional view which shows the left elbow support part and the elbow rest seen from the seated person of the embodiment. The back sectional view showing the front end part of the elbow support part and the elbow rest of the embodiment. The perspective view which shows the movable elbow rest of the embodiment. The top view which shows an example of the movable mechanism of the movable elbow rest of the embodiment. The side view of the chair which attached the movable elbow rest of the embodiment. The perspective view which shows the movable elbow rest which concerns on one of the modifications of this invention. The top view of the chair which attached the movable elbow rest which concerns on the modification. The perspective view which shows the movable elbow rest which concerns on one of the modifications of this invention. The top view of the chair which attached the movable elbow rest which concerns on the modification. The perspective view which shows the movable elbow rest which concerns on one of the modifications of this invention. The side view of the chair which attached the movable elbow rest which concerns on the modification. The perspective view which shows the movable elbow rest and elbow support part which concern on one of the modifications of this invention. The perspective view which shows the movable elbow rest and elbow support part which concern on the modification. The perspective view which shows the movable elbow rest and elbow support part which concern on the modification. The perspective view which shows the movable elbow rest and elbow support part which concern on the modification.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  In this embodiment, the present invention is applied to an office swivel chair.

  As shown in FIGS. 1 to 7, the chair includes a leg 1, a support base 3 supported by the leg 1, a seat receiver 5 disposed on the support base 3, and a support supported by the seat receiver 5. The seat 7, the back support 9 that is rotatably supported by the support base 3, the back 11 attached to the back support 9, and the back tilting operation of the back 11 are performed. And a rocking mechanism 13 for moving the seat receiver 5 and the seat 7 upward and downward, and an armrest 15 provided on the backrest support 9.

《Leg composition》
As shown in FIGS. 1 to 7, the leg 1 includes a leg base 17 and a leg support 19 provided at the center of the leg base 17.

  As shown in FIG. 1 to FIG. 5 and FIG. 7, the leg base 17 is provided with a plurality of leg blades 23 radially projecting from a hub 21 provided in the center portion. 25 are provided.

  As shown in FIGS. 1 to 5, 7, and 14, the leg support 19 is a gas spring type that is elastically expanded and contracted in the vertical direction so that it can be locked at a desired position. belongs to. That is, the leg support 19 includes a gas spring main body 27 fitted to the hub 21 of the leg base 17 and a rod 29 protruding from the upper end of the gas spring main body 27. An operation button 31 for unlocking is projected. The support base 3 is attached to the upper end of the rod 29. The unlocking operation button 31 is operated by an operation lever 295 for raising and lowering which is an operation portion provided on an armrest 15 described later.

《Support base configuration》
As shown in FIGS. 7 to 13, the support base 3 includes a main frame 33 attached to the rod 29 of the leg support 19, and a front link shaft 35 and a support shaft 37 attached to the main frame 33. It will be. The front link shaft 35 is for supporting the front end portion of the seat receiver 5 through the front link 39. The support shaft 37 is for supporting the backrest support body 9 and supporting a substantially intermediate portion of the seat receiver 5 via the rear link 41.

  As shown in FIGS. 7 to 13, the main frame 33 has a boss portion 43 fitted to the upper end portion of the rod 29 in the leg support 19 and a semicircular arc shape in plan view surrounding the upper end side of the boss portion 43. The rear frame member 45, a pair of side frame members 47 extending forward from the left and right front ends of the rear frame member 45, and the front end portions of the side frame members 47 are coupled to each other and have a flat surface at the front end. A front frame member 49 is provided. The boss portion 43, the rear frame member 45, the side frame member 47, and the front frame member 49 are integrally formed by aluminum die casting or the like. A front bearing portion 51 that supports the front link shaft 35 is integrally provided on the upper surface portion of the front frame member 49, and the support shaft is located near the boundary between the rear frame member 45 and the side frame member 47. A rear bearing portion 53 that supports 37 is integrally provided. In addition, the height from the floor surface of the shaft center of the two bearing portions 51 and 53 is different, and the front bearing portion 51 is set at a higher position than the rear bearing portion 53.

  As shown in FIG. 12, the main frame 33 incorporates a tilt reaction force generation mechanism 55 that biases the backrest 11 forward.

  As shown in FIGS. 8 to 13, the tilt reaction force generating mechanism 55 includes a torque transmission bracket 57 having a base end portion supported by the support shaft 37 and a left and right torque transmission bracket 57. The movable shaft 59 is provided between the front end portions of the spring 57, and a spring 63 that elastically biases the movable shaft 59 backward as a scaffold by using a spring receiver 61 provided on the main frame 33 as a scaffold. Reference numeral 64 designates a lifting / lowering unlocking arm for pressing the unlocking operation button 31 provided on the rod 29 of the leg post 19, and as shown in FIGS. , A lifting wire for transmitting the operating force of the lifting control lever 295 provided on the armrest 15 to the lifting lock release arm 64. When the wire 297 is pulled by operating the operation lever 295, the base end boss portion 66 externally fitted to the support shaft 37 rotates and is provided integrally on the opposite side of the wire 297 across the base end boss portion 66. The unlocked arm 64 is rotated downward.

  The support base 3 is covered with an upper cover 65 and a lower cover 67 as shown in FIGS. 3 to 6, 10, and 11.

  As shown in FIGS. 10 and 11, the upper cover 65 covers the support base 3 from the upper surface side, and is provided with an upper locking claw 69 protruding downward to engage with the support base 3. The lower cover 67 covers the support base 3 from the lower surface side, and is provided with a lower locking claw 71 protruding upward to engage with the support base 3. Further, the upper cover 65 and the lower cover 67 are arranged so that the opening end edges 73 and 75 abut each other.

  On the outer peripheral surface of the front side of the main frame 33 of the support base 3, in other words, on the flat surface of the front end of the front frame member 49, as shown in FIGS. And a common upper / lower mounting portion 77 for mounting the upper and lower sides.

  More specifically, the main frame 33 of the support base 3 includes an upper locking claw 69 of the upper cover 65 and a lower locking claw 71 of the lower cover 67, as shown in FIGS. An upper and lower common mounting portion 77 for engaging is provided, and the upper and lower common mounting portion 77 is engaged with an engagement end surface 79 with which the upper locking claw 69 is engaged and with the lower locking claw 71. An end face 81, a locking end face 83 for preventing lateral shift for locking lateral shift of the upper locking claw 69, and a locking end face 85 for preventing lateral shift for locking lateral shift of the lower locking claw 71 are provided. Yes.

  As shown in FIGS. 8, 10, and 11, the upper and lower common mounting portion 77 is provided on the outer peripheral surface 87 of the front end of the front frame member 49 in the main frame 33, and the outer peripheral surface 87 of the front end is rectangular. It is recessed in the shape. In the upper and lower mounting part 77, the upper side is an engagement end surface 79 with which the upper locking claw 69 of the upper cover 65 is engaged, and the lower side is an engagement end surface 81 with which the lower locking claw 71 of the lower cover 67 is engaged. Further, in the upper and lower common mounting portion 77, the left and right sides are locking end surfaces 83 and 85 for preventing lateral displacement with respect to the upper locking claw 69 and the lower locking claw 71 of the upper cover 65 and the lower cover 67.

  Note that, in the vicinity of the middle in the front-rear direction on the outer periphery of the main frame 33, as shown in FIGS. 8 to 10, 12, and 13, an upper dedicated mounting portion 89 for mounting the upper cover 65 and a lower cover 67 are mounted. And a lower dedicated mounting portion 91. The upper cover 65 is provided with a claw 93 that engages with the upper dedicated mounting portion 89, and the lower cover 67 is provided with a claw 95 that engages with the lower dedicated mounting portion 91.

  Further, as shown in FIG. 10, an upper dedicated mounting portion 97 for mounting the upper cover 65 and a lower dedicated mounting portion 99 for mounting the lower cover 67 are provided at the rear end of the outer periphery of the main frame 33. Yes. The upper cover 65 is provided with a claw 101 that engages with the upper dedicated mounting portion 97, and the lower cover 67 is provided with a claw 103 that engages with the lower dedicated mounting portion 99. In other words, the rear frame member 45 of the main frame 33 includes a substantially horizontal central protrusion that is the lower dedicated mounting portion 99 and a pair of upper dedicated mounting portions 97 disposed on both sides of the lower dedicated mounting portion 99. Side ridges are provided. The upper dedicated mounting portion 97 is arranged with a height different from that of the lower dedicated mounting portion 99.

  In addition to the above, the opening edges 73 and 75 of the upper and lower covers 65 and 67 are provided with grooves, except for the vicinity of the rotating shaft, so that the outer peripheries of the upper cover 65 and the lower cover 67 are also brought into contact with each other. Specifically, one of the upper cover 65 and the lower cover 67 has a fitting recess exposed to the outside, and the other has an L-shaped groove that can be fitted to each other with the fitting recess exposed to the inside. . In this way, the upper and lower covers 65, 67 adapted to engage with the upper and lower dedicated mounting portions 89, 91 of the support base 3 are arranged so as to cover the claws 93, 95 at a certain distance from the support base 3. Even if it has comprised, upper and lower covers 65 and 67 can be reliably fitted.

  The left and right front links 39 are rotatably attached to the bearing portion 51 in front of the support base 3 described above via the front link shaft 35. The structure for attaching the front link 39 to the support base 3 is as follows. That is, as shown in FIGS. 8 to 13, the support base 3 includes a bearing portion 51 that supports the front link shaft 35 on the left and right sides, and a pair of opposed flat surfaces 105 that are perpendicular to the axial direction. The front link 39 is located between the planes 105 in the rotation range (U) when used so that the chair can perform its original function, and the front link 39 can be inserted into and removed from the support base 3 (not shown). In the rotation range at the time of insertion / removal, a plane corresponding portion 107 located outside the plane 105 is provided, and the front link 39 is rotatably supported by the support base 3 via the front link shaft 35.

  In other words, as shown in FIGS. 8 to 13, the support base portion 3 is positioned forward and upward at a bearing portion 51 that supports the front link shaft 35 and a position adjacent to the axial direction of the bearing portion 51. And an open link arm housing portion 109. The link arm housing portion 109 is formed between a pair of flat surfaces 105 orthogonal to the front link shaft 35. The front link 39 has a shaft hole 113 for holding the front coupling shaft 111 at the upper end portion and a boss portion 115 that is externally mounted on the front link shaft 35 at the base end portion. A link arm 117 is provided. The link arm 117 has a plane corresponding portion 107 corresponding to the link arm accommodating portion 109.

  In the in-use rotation range (U), the plane corresponding portion 107 of the link arm 117 is located between the opposing planes 105 of the link arm accommodating portion 109. Therefore, the left and right front links 39 are prohibited from being detached from the front link shaft 35 and the front connecting shaft 111. On the other hand, in the rotation range at the time of insertion / removal, the plane corresponding portion 107 of the link arm 117 is located outside the plane 105 facing the link arm housing portion 109. Therefore, the left and right front links 39 can be detached from the front link shaft 35 and the front connecting shaft 111. In the assembled state, the front link 39 is set so as not to rotate to the rotation range during insertion / removal. At the time of assembly, the front link 39 is laid back to the front link shaft 111 passed through the front link mounting portion 121 of the seat 5 and the front link shaft 35 passed through the front bearing portion 51 of the main frame 33 from the left and right. Fit. In this state, the front link 39 is tilted forward, and the link arm 117 of the front link 39 is fitted between the opposing flat surfaces 105 of the link arm housing portion 109. Thereafter, the rear link shafts 123 are fitted into the rear link mounting portions 127 located substantially in the middle of the seat receiver 5 and the back support arms 151 are attached from the left and right, whereby the assembly state described above is achieved. That is, the left and right front links 39 can be attached to the main frame 33 without using a retaining part such as a screw.

  The seat base 5 is supported on the support base 3 configured as described above via the front link 39 and the rear link 41.

《Composition of the seat》
As shown in FIGS. 4 to 6, 12, 13, and 15, the seat 5 has a form that can be referred to as an outer shell. In this embodiment, the seat 5 is integrally formed of synthetic resin. On the lower surface of the seat 5, a front link mounting portion 121 for mounting the rotation end 119 of the front link 39 via the front connection shaft 111 and a rotation end 125 of the rear link 41 via the rear connection shaft 123 are provided. A rear link attachment portion 127 for attachment is provided. The front link mounting portion 121 and the rear link mounting portion 127 are provided integrally with the seat receiver 5.

  Ribs 126 are formed in a grid pattern in the vertical and horizontal directions on the upper surface of the seat 5, and two parallel parts of the ribs 126 extend so as to protrude below the seat 5, and the front link mounting portion 121. And the rear link attaching part 127 is comprised. The left and right sides of the front link mounting portion 121 and the rear link mounting portion 127 are closed by side walls 128 and 130 having through holes. These side walls 128 and 130 may also be formed by extending a part of the rib 126 downward. The other ribs 126 are formed so as to be connected to these ribs 126 at a plurality of locations, and are designed to contribute not only to the strength of the seat 5 itself but also to the strength of the front link mounting portion 121 and the rear link mounting portion 127. ing. That is, the front link mounting portion 121 and the rear link mounting portion 127 are hollow bodies having front walls 118 and 122, rear walls 120 and 124, and left and right side walls 128 and 130, respectively. , 122, the rear walls 120, 124, and the left and right side walls 128, 130 are formed by extending a part of the rib 126 downward.

《Composition of the seat》
As shown in FIGS. 7, 14, and 15, the seat 7 includes an inner shell 129 attached to the upper surface of the seat receiver 5, a cushion 131 disposed on the inner shell 129, and the cushion 131. And a tension fabric 133 stretched on the outer surface.

  As shown in FIG. 15, the inner shell 129 is integrally formed of synthetic resin, and is fixed to the seat receiver 5 with a claw or the like (not shown). The inner shell 129 is provided with a front end drooping portion 135 that gently hangs obliquely downward on the front side, and the intermediate portion 137 bulges below the peripheral portion 139 at the boundary between the intermediate portion 137 and the peripheral portion 139. An annular step 141 is formed.

  As shown in FIGS. 14 and 15, the cushion 131 is made of urethane foam or the like, and includes a cushion hanging portion 143 along the front end hanging portion 135 of the inner shell 129 on the front side. In addition, the upper surface of the cushion 131 which is the core material of the seat 7 is provided with a plurality of uneven portions arranged in one direction, in other words, a plurality of grooves 145 arranged in the front-rear direction in this embodiment.

  As shown in FIGS. 1 to 7, 14, and 15, the tension fabric 133 has a bag shape that covers the cushion 131 and the peripheral edge 139 of the inner shell 129. The outer peripheral edge 147 of the upholstery 133 is sewn in a cylindrical shape, and a string 148 is passed through it. The edge 147 of the tension fabric 133 is wound around the lower surface side of the inner shell 129 and pulled by the string 148 so as to be hooked on the stepped portion 141 provided on the lower surface side of the inner shell 129 together with the string 148. Thereby, the edge 147 of the tension fabric 133 is arranged along the end surface of the stepped portion 141 of the inner shell 129. Further, the step portion 141 of the inner shell 129 and the edge 147 of the upholstery 133 are covered by the seat receiver 5 so as to be hidden from below. Incidentally, at the four corners of the inner shell 129, the tension fabric 133 may be fixed to the inner shell 129 by tacking, bonding, or the like. In particular, since the front side of the inner shell 129 of the present embodiment hangs down, the front corner portion of the tension fabric 133 is fixed in this way, so that it is surely prevented from coming off.

  The upholstery 133 has a visual feature portion associated with the groove 145 formed in the cushion 131. In this embodiment, the visual feature portion is embossed on the stretch fabric 133 (for example, cloth, leather, or the like to be the stretch fabric 133) with a pressing die having an uneven pattern corresponding to the visual feature portion. When the ground 133 is a synthetic fiber product, it is heated together with embossing, and when the upholstery 133 is rayon, cotton, etc., the fabric is subjected to resin processing and then embossed and heated). 149. The filament 149 is slightly recessed from the upper surface of the stretch fabric 133 and protrudes downward from the lower surface of the stretch fabric 133. In this embodiment, a plurality of the filaments 149 exist so as to be arranged in the front-rear direction, and are present at positions where they overlap with the grooves 145 of the planar cushion 131 from above when the upholstery 133 is placed on the cushion 131. . However, it is important that the line 149 is recognized by the visual sense of the seated person and others, and the groove 145 of the cushion 131 and the line 149 of the tension fabric 133 do not necessarily overlap in plan view.

  Between the cushion 131 and the tension fabric 133 stretched on the upper surface side of the cushion 131 and the visual feature portion 149 thereof, a gap due to the uneven portion 145 is interposed. The uneven portion 145 contributes to ensuring the breathability of the seating surface, and improves the sitting comfort.

<< Configuration of back support body >>
As shown in FIGS. 7 to 9, 16 and 18, and FIGS. 26 to 28, the backrest support 9 includes left and right back support arms 151 extending rearward and upward from the support base 3, and these An upper connecting member 153 that connects upper end portions 169 of the left and right back support arms 151 and a base end portion of the back support arm 151 that is integrally extended from the base end of the torque transmitting bracket 57 toward the rear upper side. The left and right back support brackets 155 that are attached to the side surfaces and the lower connecting member 157 that connects the rear ends of the left and right back support brackets 155 are provided.

  Each of the left and right back support arms 151 has a back shell (inner shell) 205 as a backrest member on the front side and supports it. As shown in FIGS. 1 to 9, 13, and 16 to 18, the left and right back support arms 151 are each made of resin and supported by the support base 3 so as to be rotatable. The front-rear direction extending part 159 and an upright part 161 extending continuously upward from the rear end of the front-rear direction extending part 159 are provided. In the example of illustration, the front-back direction extension part 159 and the standing part 161 have comprised the substantially U shape in the side view.

  Each back support arm 151 has a substantially L shape in a side view and extends in the front-rear direction below the seat 7. More specifically, the front end 163 of the front-rear extension 159 is a shaft that extends in the left-right direction. A shaft 37 is attached to the support base 3 so as to be able to rotate back and forth. The rear part of the forward facing part extends from the rear of the seat 7 in a slightly upwardly inclined direction with respect to the vertical direction. That is, in the standing state of the backrest 11, the upright portion 161 has a shape that extends slightly upward in the forward direction from the vertical direction and the waist portion in the height direction protrudes most forward. The upright portion 161 has a shape that can be attached so as to fit the back portions of the left and right side edges of the back shell 205. That is, the chair in the present embodiment is formed by attaching resin back shells 205 to the front surfaces of the left and right back support arms 151 that extend rearward and upward from the support base 3, and the back support arms 151 The waist and the lower side of the back shell 205 are directly supported. In the present embodiment, the upper end portion 169 of the back support arm 151 is assumed to be located near the waist of the seated person.

  Further, each back support arm 151 is fitted to the end portion 165 of the support shaft 37 provided on the support base portion 3 from the outside to the base end portion thereof, that is, the front end portion 163 of the front-rear direction extending portion 159. A shaft mounting portion 167 is provided. Each back support arm 151 is provided with an arm protrusion 171 for attaching the upper connecting member 153 to the tip, that is, the upper end 169 of the upright portion 161.

  As shown in FIGS. 3 to 9 and FIGS. 16 and 26 to 28, the shaft mounting portion 167 of each back support arm 151 is opened only inward so as to fit the end portion 165 of the support shaft 37. A shaft hole 173 is provided. Specifically, the end 165 of the support shaft 37 is fitted into the shaft hole 173 via a bush 175 so as to be relatively rotatable. The bush 175 is inserted from the inner surface side of the back support bracket 155 before the support shaft 37 is mounted, and the support shaft 37 is fitted into the inner periphery of the bush 175 so as to be relatively rotatable. The flange portion 177 of the bush 175 is located between the back support bracket 155 and the main frame 33. The shaft mounting portion 167 is fitted on the outer periphery of the bush 175, and the end portion 165 of the support shaft 37 is covered by the shaft mounting portion 167. The shaft hole 173 has a tapered shape with a large diameter on the opening end side, and the support shaft 37 has a cylindrical shape. The bush 175 has a shape filling the space between the inner peripheral surface of the shaft hole 173 and the outer peripheral surface of the shaft 37. That is, the outer peripheral surface of the bush 175 has a tapered shape, and the inner peripheral surface has a cylindrical shape having the same cross-sectional shape in each part.

  Note that the rear link 41 is integrally provided on the outer periphery of the shaft mounting portion 167 as shown in FIGS. 3 to 9, 16 and 17, and FIGS. 26 to 28. Also, cover members 181 that cover the half 179 of the lower connecting member 157 are integrally projected on the inner side surface of each back support arm 151 in the vicinity of the shaft mounting portion 167. The cover member 181 is provided with a screw insertion hole 183. By screwing a screw 187 inserted into the screw insertion hole 183 into a screw hole 185 provided in the lower connecting member 157, the left and right back holes 183 are inserted. A support arm 151 is attached to the lower connecting member 157.

  In this state, the left and right back support arms 151 are coupled to each other via the lower connecting member 157, so that the shaft mounting portion 167 does not come out of the support shaft 37. That is, the left and right back support brackets 155 whose rear ends are connected by the lower connecting member 157 are supported by the support base 3 via the support shaft 37, and both ends of the support shaft 37 projecting outward from the back support bracket 155. Since the left and right back support arms 151 that rotate together with the back support bracket 155 are supported by the part 165, the left and right back support arms 151 are attached from the left and right outside of the back support bracket 155, so 37, the back support bracket 155 and the lower connecting member 157 can be covered. In this embodiment, the ends 189 of the cover member 181 of the left and right back support arms 151 are closely abutted in the assembled state.

  As shown in FIGS. 7, 18, 18, and 28, the arm projecting portion 171 of the back support arm 151 is for attaching the end portion of the upper connecting member 153, and includes a screw insertion hole 191 and the screw insertion hole. And a nut (not shown) having a screw hole continuous with 191.

  As shown in FIGS. 7 and 18, the upper connecting member 153 is a metal metal having a channel shape, and is installed between the arm projecting portions 171 of the left and right back support arms 151 and screwed to the nut. The screw 195 is attached to each back support arm 151. That is, the upper connecting member 153 has a shape that opens rearward, and is fitted between the upper end portion 169 of the back support arm 151 by being fitted to the arm projecting portion 171 from the front side.

  As shown in FIGS. 9, 12, 13, 16, and 17, the back support bracket 155 is made of metal and is integrally formed with the torque transmission bracket 57. Via the main frame 33 so as to be rotatable.

  As shown in FIGS. 9, 16 and 17, the lower connecting member 157 is made of metal, and both ends thereof are rigidly connected to the rear end of the back support bracket 155 by welding. The lower connecting member 157 has a skeletal function of the back support arm 151 made of synthetic resin in cooperation with the back support bracket 155. Moreover, it also has a function as a base for preventing the back support arm 151 fitted from the left and right from being detached from the left and right. Further, the lower connecting member 157 receives a backward tilting load acting on the backrest 11 via the back support arm 151, and transmits the load via the back support bracket 155 for torque transmission of the tilt reaction force generation mechanism 55. It also has a function of transmitting to the bracket 57.

  The backrest 11 is supported by the backrest support body 9 as described above.

《Composition of backrest》
As shown in FIGS. 1 to 7, the backrest 11 is made of a resin-made back shell 205 that is curved until it becomes substantially horizontal at the top 201 and has an opening 203 for promoting elastic deformation at an almost middle portion thereof. The back shell 205 includes a back support member 209 that supports a leading edge 207 located behind the top portion 201 of the back shell 205, and a tension fabric 206 attached to the surface side of the back shell 205.

  The back shell 205 forms a backrest surface on which the seated person rests (the backrest surface is formed regardless of the presence or absence of the tension fabric 206). As shown in FIGS. 2 to 7, 19, 20, 22, 22 to 24, 26, and 27, the back shell 205 is made of resin and supported by the backrest support 9. More specifically, the seating surface of the back shell 205 is made of a so-called resin shell, and has a forward-facing concave shape in which the left and right side edges in the plan view protrude forward at the waist portion in the height direction, and the vertical direction. The side section has a three-dimensional shape forming a forward convex shape protruding forward. In other words, the back shell 205 has a concave shape facing forward in plan view in the vicinity of the upper end portion 169 of the back support arm 151, and is curved so as to cover the upper surface of the back support arm 151 rearward and rearwardly upward. It is growing. The waist portion of the back shell 205 located in the lower region 229 of the back shell 205 is provided with slits, cutouts, etc. for promoting elastic deformation in order to firmly support the waist of the seated person. Absent.

  The back shell 205 is slightly tilted forward below the waist corresponding to the upper end 169 of the back support arm 151, is curved backward at the waist, and slightly tilted rearward above the waist. The back support arm 151 directly supports the back shell 205 at a portion below the waist of the back shell 205, that is, at the waist and a portion below the waist. The back support arm 151 is located at the rear portion of the back shell 205 and supports the back surface of the back shell 205 at a portion below the waist of the back shell 205.

  The back shell 205 is curved until it is substantially horizontal at the top 201, and has an opening 203 for promoting elastic deformation at a substantially intermediate portion. In other words, a plurality of openings 203 extending in the vertical direction are provided in the portion extending from the waist to the rear upper side. More specifically, the back shell 205 has a plurality of strip-like members 213 extending in the vertical direction in the upper region 211, and the opening 203 is formed between the strip-like members 213. Further, the back shell 205 has a shape corresponding to the waist of the seated person, that is, the waist-corresponding portion 215 having a wide left and right width and gradually becoming narrower as it goes upward in a front view.

  As shown in FIGS. 2 to 7, 19, 20, 22, and 24, the upper region 211 is provided continuously on the front portion 217 that receives the back of the seated person and the upper edge of the front portion 217. The top portion 201 includes an upper curved portion 219 that is curved until it is substantially horizontal, and a back portion 221 that is provided continuously from the rear edge of the upper curved portion 219 and curves downward and hangs down. A groove 223 that opens downward is formed at the leading edge 207 of the back surface portion 221.

  As shown in FIG. 24, the groove 223 has a main insertion portion 225 for fitting the back support member 209, and the back support member 209 in a state where the back support member 209 is fitted to the main insertion portion 225. And a sub-insertion portion 227 that opens on the back side. That is, the groove 223 provided in the distal end edge 207 of the back shell 205 is a stepped groove shape in which a main insertion portion 225 and a sub insertion portion 227 are continuously formed, and the main insertion portion 225 has a back support member. When an upper mounting portion 251 (described later) 209 is inserted, only the auxiliary insertion portion 227 is left open and left. The sub insertion portion 227 is continuous with a side edge groove 235 described later, and by attaching the tension fabric 206 using the sub insertion portion 227 and the side edge groove 235, the front shell 205 is moved from the front surface to the upper back surface side. It can be covered with a stretch fabric 206. It should be noted that a rib 228 for adjusting elastic deformation is formed on the belt-like member 213 of the back surface portion 221.

  Further, the lower region 229 of the back shell 205 has a concave shape in which the left and right sides protrude forward from the middle in the left-right direction, as shown in FIGS. 2 to 7, 19, 20, 23, 26 and 27. There is no. In the lower region 229, a protrusion 231 continuous with the strip member 213 is formed, and a thin portion 233 continuous with the opening 203 is formed between adjacent protrusions 231. A lower region 229 of the back shell 205 has a portion 215 corresponding to the waist of the seated person raised upward in a side view, and is curved so that the center in plan view is recessed.

  As shown in FIGS. 1, 2, 4, 6, 19, 22, 22, 23, 26, and 27, the back shell 205 has side edges that are open outwardly on the left and right side edges, respectively. Grooves 235 are provided, and these side edge grooves 235 and sub-insertion portions 227 in the grooves 223 are continuous. In addition, a lower edge groove 237 that is continuous with the side edge groove 235 is provided at the lower end of the back shell 205.

  As shown in FIGS. 1 to 6, 23, 26, and 27, the back shell 205 has a lower portion 239 attached to the front surface of the back support arm 151 and an upper portion 243 that is the back support member 209. Supported by The attachment of the lower part 239 of the back shell 205 will be described. A plurality of nut holes 204 are formed on the front side of the upright portion 161 of the left and right back support arms 151 so as to be spaced apart from each other. On the other hand, screw insertion holes respectively corresponding to the nut holes 204 are provided on the left and right sides of the lower portion 239 of the back shell 205. Accordingly, the mounting screws 241 are inserted through the screw insertion holes from the front and then screwed into the nut holes 204 to tighten the left and right sides of the lower portion 239 of the back shell 205 between the left and right back support arms 151. It can be fixed to the front surface of the upright portion 161. The screw 241 is concealed when the upholstery 206 is provided.

  As shown in FIGS. 1, 2, 4 to 7, 19, 21, 21, 22, and 24 to 27, the back support member 209 is opened to the left and right and below the back surface of the back shell 205. It is a plate-like one disposed so as to form a space 245, and is supported by the backrest support 9 to control the deflection of the back shell 205 in the front-rear direction. In other words, the plate-like member is disposed rearwardly from the backrest surface that receives the weight of the seated person, and the upper edge of the plate-like member is connected to the backrest surface. And the space formed between the said backrest surface and a plate-shaped member is open | released in the left-right direction from the top to the bottom. Thereby, since air flows in the left-right direction of the chair, air permeability is improved.

  The back support member 209 has a concave shape when viewed from the front in which the left and right sides protrude forward from the middle in the left-right direction. A supporting member main body 247 having a lower mounting portion 249 provided at the lower end of the supporting member main body 247 and attached to the upper connecting member 153; and a main fitting portion 225 of the groove 223 provided at the upper end of the supporting member main body 247. And the rib 253 formed over the upper mounting portion 251, the support member main body 247 and the lower mounting portion 249. Note that the left and right end edges of the back support member are thicker than the middle part, and this functions as a peripheral reinforcing material.

  The support member main body 247 is plate-shaped as shown in FIGS. 4 to 7, 18, 19, 19, 21, 22, and 24 to 27. A protruding curved shape is formed, and a bent portion 255 is formed below the upper mounting portion 251. The bent portion 255 is shaped such that the upper side of the bent portion 255 is inclined forward with respect to the lower side. In other words, the bent portion 255 is bent in a square shape when viewed from the side.

  As shown in FIGS. 4 to 7, 19, 21, and 24, the upper mounting portion 251 has a thickness dimension that can be closely fitted to the main fitting portion 225, and is in a fitted state. And attached to the back shell 205 using screws 263. That is, the upper attachment portion 251 is a plate-like member extending upward from the upper end of the support member main body 247, and the upper end portion of the rib 253 is located on the front surface thereof. On the front surface of the upper mounting portion 251, the plate nut 257 is disposed between the adjacent ribs 253, and the upper end portion thereof is fitted into the main fitting portion 225 of the groove 223, thereby positioning and holding the plate nut 257. Be able to. The back support member 209 can be attached to the back shell 205 by screwing the screw 263 inserted from the back side through the screw hole 261 of the back shell 205 into the screw hole 259 of the plate nut 257. It has become. In this state, the plate nut 257 is hidden by the back shell 205 and the back support member 209.

  As shown in FIGS. 4 to 7, 19, 21, 25, and 27, the lower mounting portion 249 includes a rear wall 265 that continuously extends downward from the lower end of the support member body 247, and this A top wall 267 extending forward from the upper end of the rear wall 265 and connecting the ribs 253 located in the middle to each other, and a front wall 269 suspended downward from the front edge of the top wall 267, The upper connecting member 153 has a shape opened downward so as to be fitted from above. A screw insertion hole 273 for inserting a screw 271 for attaching the back support member 209 to the upper connecting member 153 is formed in the front wall 269 of the lower attachment portion 249.

  As shown in FIGS. 7, 19, 21, 22, 24 to 27, the ribs 253 extend in the vertical direction, and a plurality of ribs 253 are provided on the front surface of the back support member 209. These ribs 253 are shaped so that the projecting dimension gradually decreases toward the upper side. The ribs 253 are arranged on the left and right with a substantially constant interval. The ribs 275 located on both the left and right sides are cut off at the lower end of the support member main body 247 and do not extend to the lower mounting portion 249. The top wall 267 is located below the ribs 275 located on the left and right sides. And the front wall 269 is not provided. On the other hand, the rib 277 located in the middle extends to the front surface of the front wall 269 of the lower mounting portion 249. The protruding dimensions of the ribs 275 located on the left and right sides are set to be smaller than the protruding dimensions of the ribs 277 positioned in the middle. Further, below the back support member 209, the thickness dimension of the ribs 275 located on the left and right sides is larger than the thickness dimension of the ribs 277 located in the middle. Specifically, the ribs 275 located on the left and right sides, which are shorter in the vertical direction than the ribs 277 located in the middle, have a thickness dimension of about 6 millimeters below, while the ribs 277 located in the middle are located below. The thickness dimension is about 4 millimeters. Therefore, when the back support member 209 is viewed from the back side, it seems that there are frames extending in the vertical direction on both the left and right sides. A tension fabric 206 extending from the lower edge of the backrest 11 to the upper edge is provided on the front surface of the back shell 205.

  As shown in FIGS. 1 to 7, 22 to 24, 26 and 27, the upholstery 206 is mainly composed of a cloth material having air permeability and translucency. The end portion 279 is fastened to the outer peripheral edge of the back shell 205. More specifically, the lower end portion 281 of the upholstery 206 is pushed into the lower edge groove 237 of the back shell 205 and fixed, and the left and right end portions 283 are pushed into the side edge groove 235 of the back shell 205. It is fixed. Further, the upper portion 285 of the upholstery 206 is placed on the outer surface of the upper curved portion 219 and the rear portion 221 of the back shell 205, and the end portion 279 is pushed into the sub-insertion portion 227 of the groove 223 to be fixed. Specifically, a pushing material (not shown) is sewn on the entire periphery of the end portion of the upholstery fabric 206, and together with the pushing material, an end portion 279, a lower end portion 281 of the upholstery fabric 206, and left and right end portions. 283 is attached to the sub-insertion portion 227, the lower edge groove 237, and the side edge groove 235 of the groove 223 of the back shell 205, respectively. Note that the head of the screw 263 that connects the back shell 205 and the back support member 209 is covered with the tension fabric 206 attached to the back shell 205.

  The backrest 11 as described above is visible in a state in which both side edges of the back shell 205 protrude outward from both side edges of the back support member 209 in the rear view. In addition, the back side of the upholstery 206 can be visually recognized through the opening 203 of the back shell 205 when viewed obliquely from the rear, and the rib 253 of the back support member 209 can be visually recognized from the perspective viewed from diagonally forward. It is.

  The backrest 11 configured as described above and the seat 7 are interlocked by a locking mechanism 13.

《Configuration of locking mechanism》
As shown in FIGS. 4 to 13, the locking mechanism 13 is of a weight sensing type in which the seat 7 is moved upward while being tilted in accordance with the backward tilting motion of the backrest 11.

  Specifically, as shown in FIGS. 4 to 13, the locking mechanism 13 includes a support base portion 3 that holds a front link shaft 35 on the front side and a support shaft 37 on the rear side, and a lower end portion on the front side. After the front link 39 that is rotatably supported by the support base 3 via the link shaft 35 and the lower end portion are integrated with the shaft mounting portion 167 of the back support arm 151 supported by the support shaft 37. The link 41 and the front link attaching part 121 are connected to the turning end 119 of the front link 39 via the front connecting shaft 111 and the rear link attaching part 127 is connected to the turning end of the rear link 41 via the rear connecting shaft 123. The main body is composed of a seat 5 connected to 125.

  That is, as shown in FIGS. 4 to 13, the locking mechanism 13 supports the seat base 5 supporting the seat 7 on the support base 3 by the front link 39 and the rear link 41 inclined in the same direction. In accordance with the backward tilting operation of the back support arm 151 supported by the base 3, the front link 39 and the rear link 41 are rotated in the upright direction to lift the seat receiver 5 upward. When the backrest 11 is tilted backward, the front portion of the seat 7 is lifted more than the rear portion of the seat 7. That is, in the normal backrest and seat synchro-rocking mechanism, the seat is tilted only downward in accordance with the backward tilting motion of the backrest, but the weight sensing type locking mechanism as shown in this embodiment 13, unlike a normal locking mechanism, as shown by a two-dot chain line in FIG. 13, the seat 7 is tilted against the load of the seated person while the seat 7 is tilted in accordance with the backward tilting motion of the backrest 11. It is configured to lift.

  More specifically, as shown in FIG. 13, when the backrest 11 is not tilted backward, the forward link 39 has a forward inclination degree larger than the forward inclination degree of the rear link 41. Is set. In other words, the inclination angle α with respect to the horizontal line at the front link 39 is set smaller than the inclination angle β with respect to the horizontal line at the rear link 41 when the backrest 11 is not tilted backward. Further, the center of rotation of the front link 39 relative to the support base 3 is set at a position higher than the center of rotation of the rear link 41 relative to the support base 3. In other words, the axis of the front link shaft 35 is set at a position higher than the axis of the support shaft 37 by a distance h. The effective length dimension of the front link 39, that is, the inter-center distance L1 between the front link shaft 35 and the front connecting shaft 111, and the effective length dimension of the rear link 41, that is, the support shaft that is the rear link shaft. 37 and the rear connecting shaft 123 are set to be substantially the same distance L2. Further, the back support arm 151 is pivotally supported by a portion of the support base 3 that is in front of the leg column 19. In other words, the shaft mounting portion 167 of the back support arm 151 is supported by the support shaft 37 positioned in front of the leg support 19 in a side view.

  The point that the forward tilting degree of the front link 39 is larger than the forward tilting degree of the rear link 41 is intended to lift the front side of the seat 7 relatively larger than the rear side during the rearward tilting. By making the forward tilting degrees of the link 39 and the rear link 41 greatly different from each other, it is possible to set the lift of the front side of the seat 7 when tilting backward to a large value. That is, the front link 39 has many operations for lifting the front portion of the seat 7, that is, the front portion 7a1 of the seating surface 7a, and the rear link 41 is mainly for the operation of moving the seat 7 rearward. As a result, while the seat surface 7a lifts the front portion 7a1 much, the rear portion 7a2 of the seat surface 7a moves backward and moves backward so as to follow the backrest 11 tilting backward. As a result, the relative positional relationship between the rear end portion of the seat 7 and the lower end portion of the backrest 11 is effectively suppressed by tilting the seat surface 7a relatively rearward.

  The point of making the rotation center positions of the front link 39 and the rear link 41 different in the vertical direction is mainly for the purpose of adjusting the level of the seat 7 when standing upright. By combining with the forward tilt degree difference, the posture of the seat 7 when the backrest 11 stands and the posture of the seat 7 when the backrest 11 is tilted backward are both set to an optimum state. By making the effective length dimension L1 of the front link 39 and the effective length dimension L2 of the rear link 41 substantially the same, the setting can be made more appropriate.

  In general, in a chair in which the back support arm is pivotally supported at a position in front of the leg column in the support base, the backrest tends to sink downward when the backrest is tilted. When the normal weight-sensing locking mechanism that allows the entire seat to lift upward when tilting is used, a large sense of incongruity, more specifically, against the seated person's expectation, As a result of the entire seat including the seat being lifted up, there is a sense of incongruity caused by the simultaneous movement of the backrest sinking motion and the seat lifting motion opposite to the sinking motion in the vicinity of the seated person's waist. According to the configuration of the embodiment, the uncomfortable feeling is alleviated. That is, although the thing of this embodiment is a body weight sensing type, even when the backrest 11 is tilted backward, the rear side of the seat 7 is not lifted greatly, so that it is difficult to give a great sense of incongruity.

  In the present embodiment, the rear link 41 rotates integrally with the back support arm 151 and the torque transmission bracket 57 around the support shaft 37 that is the rotation center of the back support arm 151. Thereby, not only the interlocking operation of the seat 7 accompanying the back tilting operation of the backrest 11 but also the accurate positioning of the seat 7 by the support base 3 via the rear link 41 is realized. Further, in the present embodiment, the rotation range of the backrest 11 is set to 20 degrees, and the angle formed by the seat surface 7a in the state where the backrest 11 is tilted back as much as possible is compared to when the backrest 11 stands. It is set to tilt 4 degrees backward. That is, in the present embodiment, the backrest 11 by the front link 39 is larger than the dimension γ2 in which the rear portion 7a2 of the seating surface 7a is lifted mainly by lifting the substantially central portion of the seat 5 when the backrest 11 is tilted backward. As a result of setting the dimension γ1 at which the front portion 7a1 of the seat surface 7a is lifted when tilted backward to be larger, the angle of the seat surface 7a when the backrest 11 is fully tilted is tilted by 4 degrees than when the backrest 11 is upright. I have to. In addition, in the present embodiment, since the rear link 41 is connected to the substantially central portion in the front-rear direction of the seat receiver 5, both the front and rear links 39, 41 when the backrest 11 is tilted backward are lifted up. However, since the front link 39 lifts the seat receiver 5 more than the rear link 41, the rear end portion of the seat receiver 5 can be set relatively lower than the front end portion, and the front end portion of the seat receiver 5 is raised. At this time, the height position of the rear end portion of the seat receiver 5 is hardly changed between when the backrest 11 stands and when it tilts backward.

《Arrangement of armrest》
The armrest 15 includes an elbow support portion 287 that protrudes forward integrally from the front surface of the upper end portion of the back support arm 151 of the backrest support body 9, and elbow pads 289 and 327 provided on the elbow support portion 287. It has.

  As shown in FIGS. 5 and 6, the outer edge 162 of the upright portion 161 of the back support arm 151 continues to the elbow support 287 while expanding outward as it goes upward. Further, as shown in FIGS. 4, 6, 28, etc., the front edge portion 162 of the upright portion 161 continues to the elbow support portion 287 while expanding forward as it goes upward. As a result, the portion to which force is applied when the seated person puts his arm on the armrest 15 has a greatly expanded shape. The outer edge 162 of the upright portion 161 also serves as the front edge. The reason is that the outer peripheral surface of the upright portion 161 (facing the rear and the outer side) has a curved shape that gradually expands forward while expanding outward. Because.

  The elbow support 287 is integrally formed with the back support arm 151 as shown in FIGS. 3 to 6, 18, 26 to 28, 29, 31, and 32. While forming an integral part with the upper end portion 169 of the upright portion 161, it has a bottomed boat shape with the internal space opened upward. The elbow support portion 287 protrudes from the height position of the back support arm 151 near the waist of the seated person, and projects outward from the outer edge portion of the back shell 205 (and the tension fabric 206) at the same height position. After that, it extends forward from the back shell 205. The elbow support 287 has a rear end connected to the back support arm 151, while the front end is not supported by other members.

  FIG. 27 shows a state where a fixed elbow rest 289 is already mounted on the elbow support 287. In plan view, except for the spacers 305 and 333 which are the rear ends of the elbow pads 289 and 327, the contour lines of the mounting bases 299 and 329 of the elbow pads 289 and 327, and the upper ends 169 of the elbow support portions 287 and the standing portions 161 Is substantially coincident with the outline. According to FIG. 27, the elbow support part 287 extends forward, starting from the upper end part 169 of the back support arm 151 and extending outwardly so as to draw an arc (or curve). A contour line 286 having a substantially arc shape (true arc or elliptic arc) in plan view is drawn at a connecting portion between the upright portion 161 and the elbow support portion 287 of the back support arm 151.

  The upper surfaces of the upper end portions 169 of the elbow support portion 287 and the back support arm 151 are planarly expanded in the front-rear direction. The outer peripheral edge of the upper surface of the upper end portion 169 of the elbow support portion 287 and the back support arm 151 is a step portion 288 that falls downward as compared with other portions of the upper surface. As shown in FIG. 32, the central portion in the left-right direction of the bottom surface 341 of the elbow support portion 287 bulges downward. The lower edge 345 of the outwardly facing side surface 343 that intersects the bottom surface 341, in other words, the intersection line of the bottom surface 341 and the outwardly facing side surface 343 (the ridgeline where the outward side surface 343 is refracted from the bottom surface 341). The height position of 345 is higher than the lowermost edge of the bottom surface 341. Similarly, the lower edge 349 of the inwardly facing side surface 347 that intersects with the bottom surface 341, in other words, the intersection line between the bottom surface 341 and the inwardly facing side surface 347 (the inwardly facing side surface 347 is refracted from the bottom surface 341). The height position of the ridge line 349 is also higher than the lowermost edge of the bottom surface 341.

  One elbow support portion 287, in this embodiment, a bottom wall 291 at the front end portion of the right elbow support portion 287 when viewed from the seated person, is formed with a penetrating window 293, and the lower side through the window 293 The operation lever 295 is protruded. The operation lever 295 is for operating the operation button 31 for unlocking the leg strut, and is accommodated in the inner space of the elbow support portion 287 except for the operation end portion 296 operated by the finger of the seated person. . The rotation shaft 309 of the operation lever 295 extends in the left-right direction, and both left and right end portions thereof are pivotally supported by bearing bodies 311 provided in the internal space of the elbow support portion 287, respectively. The bearing body 311 is mainly composed of a plate-like body that stands upright from the bottom wall 291 of the elbow support portion 287 and faces the left and right sides, and is formed by cutting out a bearing hole having a substantially semicircular shape when viewed from the side. It is something. The rotating shaft of the operation lever 295 engages with the bearing hole on the upper edge of the bearing body 311.

  The operation lever 295 and the operation button 31 are connected by a wire 297. One end portion of the wire 297 connected to the operation lever 295 is housed in the inner space of the elbow support portion 287 together with the base end portion of the operation lever 295. When the operation end 296 of the operation lever 295 is lifted upward, the wire 297 is pulled as shown by a two-dot chain line in FIG. The operation force applied to the operation lever 295 is transmitted to the operation button 31 by the wire 297, so that the operation button 31 can be operated, and the leg strut can be locked / unlocked. In short, when the operation lever 295 is operated, the back-seat lifting function of the chair is operated.

  A pressing plate 313 for preventing the operation lever 295 and the tube 300 from being detached is attached above the rotating shaft 309 of the operation lever 295 and the tube 300 containing the wire 297. The holding plate 313 is fixed to the bottom wall 291 of the elbow support 287 using screws 315.

  The internal space of the elbow support portion 287 communicates with the wire guide space 298 formed in the standing portion 161 of the back support arm 151. The wire guide space 298 extends in the vertical direction, and a part or all of the wire guide space 298 opens forward. The lower end portion of the wire guide space 298 reaches just above the longitudinally extending portion 159, and is located slightly below the lower end of the back shell 205 in a state where the lower portion 239 of the back shell 205 is attached to the upright portion 161. Open to the front. Therefore, the wire 297 connected to the operation lever 295 is led from the inner space of the elbow support portion 287 to the lower end portion of the wire guide space 298, and then reaches the support base portion 3 along the longitudinally extending portion 159. The

  The elbow pads 289 and 327 are detachable from the elbow support 287. Thereby, arbitrary things can be selected and used out of the multiple types of elbow pads 289 and 327 which can be attached to the common elbow support part 287. The elbow rest includes a fixed type 289 and a movable type 327.

  1 to 5, FIG. 7 and FIG. 18, FIG. 19, FIG. 27, FIG. 29 to FIG. 33, an elbow rest 289 of the fixed type has an elbow rest body 301 on which a seated person's arm is placed. In this embodiment, it is not displaceable with respect to 287. The elbow rest 289 is integrally provided with an attachment base 299 that is directly attached to the elbow support 287 and an elbow rest main body 301 that is supported by the attachment base 299.

  The mounting base 299 includes a base 303 that is attached to the upper end 169 of the elbow support 287 and the back support arm 151, and a spacer 305 that extends substantially horizontally from the inner end of the base 303. The base 303 is hooked to the elbow support 287 by a locking mechanism on the front side, and the rear side is attached to the front side of the back support arm 151 using screws 307.

  The locking mechanism is interposed between the front end portion of the elbow support portion 287 and the lower surface on the front side of the base body 303. Specifically, a tether 317 (which may be a bolt screwed to the elbow support 287) protruding upward is provided at the front end of the elbow support 287, and this tether is provided on the front lower surface of the base 303. A hooked portion 319 that engages with the upper end portion of 317 is provided, and these are used as a locking mechanism. The upper end of the anchoring body 317 projects outwardly just like the head of a bolt. As shown in FIGS. 30 and 33, the hooked portion 319 has a reverse-side-upside-shaped saddle shape in which the side wall 320 hangs from the lower surface on the front side of the base body 303 and the bottom wall 321 is bent substantially horizontally. And open to the rear. The rear edge of the bottom wall 321 is cut out in a partial arc shape in plan view so that a shaft portion below the upper end portion of the anchoring body 317 is accommodated.

  The upper surface of the outer peripheral portion of the base body 303 is planarly expanded in the front-rear direction. The outer peripheral edge is a stepped portion 304 that is recessed upward compared to other portions of the upper surface. A convex piece 323 protrudes downward from a location that is slightly inward from the outer periphery of the base body 303.

  A contact portion 325 that hangs downward and contacts the back support arm 151 from the front is provided at a position corresponding to a boundary region between the elbow support portion 287 and the upper end portion 169 of the back support arm 151 on the rear side of the base 303. A screw insertion hole 326 is formed in the contact portion 325.

  The spacer 305 is for filling a space where the top wall 267 directly below the rib 275 is not present, and has a plate shape substantially continuous with the top wall 267 of the lower mounting portion 249 of the back support member 209.

  When attaching the mounting base 299 of the elbow support 287 to the elbow support 287, the mounting base 299 is placed on the elbow support 287 in a state slightly shifted forward compared to the elbow support 287, and the mounting base 299 is rearward Displace to. Then, the hooked portion 319 on the lower surface on the front side of the mounting base 299 engages with the anchoring body 317 fixed to the front end portion of the elbow support portion 287 from the front. As a result, as shown in FIGS. 31 and 33, since the upper end portion of the anchoring body 317 is positioned directly above the bottom wall 320 of the hooked portion 319, the front side of the mounting base 299 is lifted from the elbow support portion 287. Is suppressed. After that, the screw 307 is inserted into the screw insertion hole 326 of the contact portion 325 from the front, and is screwed and tightened into the nut hole 308 formed in the back support arm 151 in advance.

  When the attachment base 299 is attached to the elbow support 287, the step 304 on the outer periphery of the attachment base 299 and the step 288 on the outer periphery of the upper end 169 of the elbow support 287 and the back support arm 151 are fitted. The convex piece 323 of the mounting base 299 is inserted into the internal space of the elbow support portion 287. As shown in FIGS. 18 and 27, the spacer 305 is closely interposed between the upper surface of the upper connecting member 153 and the lower end surfaces of the ribs 275 located on the left and right sides of the back support member 209. Is done.

  That is, the upper end portion 169 of the upright portion 161 of the elbow support portion 287 and the back support arm 151 is supported at a portion excluding the rear end portions of the attachment bases 299 and 329 of the elbow pads 287 and 327. Even if the spacers 305 and 333 which are the rear ends of the mounting bases 299 and 329 are temporarily supported, they are due to the upper connecting member 153. The mounting bases 299 and 329 except for the spacers 305 and 333 are placed across the upper surface of the elbow support portion 287 and the upper surface of the upper end portion 169 of the upright portion 161.

  However, the upper end portion of the upright portion 161 (which is connected to the rear end portion of the elbow support portion 287 and located at the same height as the rear end portion of the elbow support portion 287) is regarded as a part of the elbow support portion 287. It doesn't matter. In this case, the elbow support part 287 is placed immediately above the standing part 161 of the back support arm 151.

  When the attachment base 299 of the elbow rest 287 is removed from the elbow support 287, the procedure reverse to the above may be taken. That is, the screw 307 is removed from the nut hole 308 and extracted from the screw insertion hole 326, and the mounting base 299 is displaced forward to release the engagement between the hooked portion 319 and the tether 317.

  Therefore, the movable type elbow rest 327 shown in FIGS. 34 to 36 is an embodiment in which the elbow rest main body 331 on which the seated person's arm is placed is slidable in the front-rear direction with respect to the elbow support portion 287. is there. The elbow rest 327 is interposed between an attachment base 329 that is directly attached to the elbow support 287, an elbow rest body 331 that is a separate body from the attachment base 329, and the attachment base 329 and the elbow rest body 331. A movable mechanism is provided, and the mounting base 329, the elbow pad main body 331, and the movable mechanism are integrated into the unit so as to be detachable from the elbow support portion 287.

  The mounting base 329 is a member that is at least partially common to the mounting base 299 of the fixed type elbow rest 287. The attachment structure of the attachment base 329 to the elbow support portion 287 is also common to at least a part of that of the attachment base 299 of the fixed type elbow rest 287. On the lower surface on the front side of the mounting base 329, a hooking portion (not shown) similar to the mounting base 299 is provided. Further, a contact portion 335 that hangs downward and contacts the back support arm 151 from the front is provided at a position corresponding to a boundary region between the elbow support portion 287 and the upper end portion 169 of the back support arm 151 on the rear side of the mounting base 329. There is a screw insertion hole 336 in the contact portion 335. Needless to say, the screw 307 is inserted into the screw insertion hole 336. The point that the spacer 333 extends substantially horizontally from the inner end is the same as the mounting base 299.

  The movable mechanism is a moderation that selectively selects the slide guide (or rail) structure for guiding the movement of the elbow rest main body 331 along the front-rear direction relative to the mounting base 329 or the elbow rest main body 331 at any one of a plurality of positions in the front-rear direction. Includes a moderation mechanism for stopping. These slide guide structures, moderation mechanisms, and the like themselves can be configured in the same manner as that of known movable armrests (for example, as described in JP2010-063833A and JP2002-336079A). May be adopted). As an example of the slide guide structure, as shown in FIG. 35, an elbow rest main body 331 (a downward surface or a member attached under the elbow rest main body 331) and an attachment base 329 (an upward surface or an attachment base). A long hole 332 extending in the sliding direction on one inner side and a slider (pin, which is inserted into the long hole 332 and slides along the long hole 332). It is conceivable to fix the projections 330). The long holes 332 and the slider 330 are desirably arranged at positions that do not appear on the lower surface of the elbow pad main body 331 or the upper surface of the mounting base 329 even when the elbow pad main body 311 is displaced to the full movable range. In this case, there is no possibility that fingers are pinched between the long hole 332 and the slider 330. Also, a moderation mechanism is not essential.

  When the movable type elbow rest 327 is mounted on the elbow support 287, the elbow rest main body 331 is slid in the front-rear direction as shown by a solid line and a two-dot chain line in FIG. It is possible to arrange in a position.

  In the present embodiment, in the chair having the armrest 15 in which the movable-type elbow rest 327 is provided on the upper surface of the elbow support 287, the movable-type elbow rest 327 is detachably attached to the elbow support 287. And an elbow rest main body 331 disposed above the mounting base 329. The elbow rest main body 331 is interposed between the mounting base 329 and the elbow rest main body 331 along a predetermined locus. And the mounting base 329, the elbow pad main body 331, and the movable mechanism are detachably attached to the elbow support portion 287. As a result, the movable type elbow rest 327 or the fixed type elbow rest 289 can be selected and attached to the common elbow support 287.

  As a kind of elbow rest provided on the upper surface of the elbow support 287, there is a fixed type elbow rest 289, and the fixed type elbow rest 289 is detachably attached to the elbow support 287. A mounting base 299; and an elbow rest main body 301 disposed above the mounting base 299. The mounting base 299 and the elbow rest main body 301 are unitized to be attached to and detached from the elbow support portion 287. Therefore, various elbow pads 327 and 289 can be detached and replaced as an integral unit. When switching between the movable type and the fixed type, it is not necessary to replace the elbow support portion 287 and the back support arm 151. In addition, the replacement members 327 and 289 are also reduced in size, thereby reducing costs and resources. Is advantageous.

  Since the upper surface of the elbow support portion 287 is expanded in the front-rear direction in the front-rear direction, in the movable type elbow rest 327, the slide movement of the elbow rest main body 331 and the elbow support portion 287 are difficult to interfere, which is preferable.

  Since the elbow support portion 287 protrudes forward from the front surface of the upper end portion 169 of the back support arm 151 that supports the backrest 11, the load applied to the elbow pads 289 and 327 is supported by the robust back support arm 151. It is possible to secure the strength.

  There is a space opened upward in the elbow support portion 287. In addition to the operation portion 295 and the operation portion 295 for operating a predetermined function (back seat lifting function) of the chair in the internal space. Since the wire 297 for transmitting the operating force to be transmitted is disposed, the outer shape of the armrest 15 including the operation portion 295 and the wire 297 becomes compact. Since the operation part 295 and the wire 297 which are components of the operation mechanism are incorporated in the elbow support part 287 fixed to the chair, the elbow pads 327 and 289 can be attached to and detached from the elbow support part 287. The elbow pads 327 and 289 can be exchanged without affecting the operation mechanism, and the movable type and the fixed type can be switched. In other words, even if the elbow rest to be used is the movable type 327 or the fixed type 289, the operation mechanism can be operated in the same manner to exhibit the predetermined function of the chair. it can.

  Since the internal space communicates with a wire guide space 298 extending vertically along the back support arm 151 that supports the backrest 11, an intermediate portion of the wire 297 is disposed in the wire guide space 298. The terminal portion of the wire 297 can be guided to the vicinity of the seat 7.

  According to the present embodiment, a backrest member 205 that forms a backrest surface on which a seated person leans, and a back support that supports the backrest member 205 in a state where the backrest member 205 is disposed on the front surface side. The arm 151 and the back support arm 151 project from a height position near the waist of the seated person, project outward to avoid the backrest member 205, and then extend forward from the backrest member 205 to be seated. Since the chair comprising the elbow support portion 287 formed integrally with the back support arm 151 for supporting the person's arm is constructed, the back support arm 151 and the elbow support portion 287 become an integral member, and the back support arm 151 is connected to the elbow. The work process for fixing the support portion 287 becomes unnecessary, and the number of work steps can be reduced as compared with the prior art.

  Since the outer edge 162 of the upright portion 161 extending in the vertical direction and connected to the elbow support portion 287 in the back support arm 151 is connected to the elbow support portion 287 while expanding outward as it goes upward, it is large. The part where force is applied can be supported in a wide range, and the strength of the armrest 15 can be secured.

  Since the connecting portion between the upright portion 161 of the back support arm 151 and the elbow supporting portion 287 has a substantially arcuate outline 286 in plan view, the connecting portion is not angular. In other words, the rear part of the armrest 15 including the outer peripheral surface of the upright part 161 is not square, and even if it hits a person or an object, there is little risk of giving a person a pain or damaging the object.

  Since the central portion of the bottom surface 341 of the elbow support portion 287 in the left-right direction bulges downward, the thickness of the bottom wall 291 necessary for the strength of the elbow support portion 287 can be secured, and is most easily touched. The vertical dimension of the outward side surface 343 and the inward side surface 347 can be made as thin as possible. Thereby, it becomes possible to embody a light visual impression that the elbow support portion 287 is thin vertically.

  Since the left back support arm 151 and the elbow support part 287 and the right back support arm 151 and the elbow support part 287 are both fixed to the single backrest member 205, the back support member 205 is interposed therebetween. The left back support arm 151 and elbow support part 287 are integrated with the right back support arm 151 and elbow support part 287, leading to the stabilization of the structure.

  Since the rear end side of the elbow support portion 287 has a cantilever shape supported by the back support arm 151, it is not necessary to give a narrow feeling to the seated person's hands, thighs, and knees.

  According to the present embodiment, the pair of back support arms 151 are arranged on the left and right sides of the backrest 11, and the back support arms 151 extend in the up-down direction in the front-rear direction (in the above-described embodiment, the standing portions 161). An armrest 15 extending from the armrest 15 is provided, and a cavity is formed inside the armrest 15. That is, an elbow support portion 287 that extends in the front-rear direction and supports the arm (or elbow) of the seated person is provided integrally with the back support arm 151, and the internal space formed in the elbow support portion 287 is at least a cavity inside the armrest 15. As part. As a result, the amount of material used when the armrest 15 or its elbow support portion 287 that does not require the strength of the back support arm 151 is molded to have the same appearance and the same thickness as the back support arm 151 is reduced. In addition, the weight of the armrest 15 and thus the chair can be reduced. In addition, an operation part (in the above embodiment, the operation lever 295) for operating a predetermined function of the chair and a transmission member or mechanism for transmitting an operation force applied to the operation part 295 (in the above-described embodiment) to the cavity inside the armrest 15 In the above embodiment, the wire 297 and the tube 300) can be arranged.

  As the components of the armrest 15, an elbow support portion 287 that encloses an internal space that opens upward, and a member that serves as a lid that closes the opening of the elbow support portion 287 from above (in the above embodiment, the elbow rests 289, 327). Or the mounting bases 299 and 329), and the operation unit 295, the transmission member or the transmission mechanisms 297 and 300 are accommodated on the elbow support unit 287 side. In the form, the rotation center shaft 309) and the transmission members or transmission mechanisms 297, 300 are not visible from the outside, and the appearance is improved. In addition, when assembling these members 295, 297, and 300, the elbow support 287 can be operated from above.

  The inner space of the elbow support part 287 extends over substantially the entire area of the front and rear dimensions of the elbow support part 287, and the lid bodies 299, 329 that close the opening of the elbow support part 287 also extend over substantially the entire area of the opening. The operation of assembling the operation units 295, 297, and 300 is further simplified.

  The internal space of the elbow support portion 287 reaches a portion 161 extending in the vertical direction of the back support arm 151, and a cavity (wire insertion space 298 in the above embodiment) communicating with the internal space is formed in the portion 161. Since it forms, it contributes to the further weight reduction of the elbow support part 287 and the back support arm 151. FIG.

  By inserting a transmission member or mechanism 297, 300 for transmitting an operating force applied to the operation unit 295 into a cavity 298 formed in the portion 161 of the back support arm 151, the transmission member or mechanism 297, 300 is supported by the elbow. It can be guided downward along the portion 161 from the internal space of the portion 287. Therefore, the transmission member or mechanism 297, 300 is exposed to the vicinity of the member (in the above embodiment, the gas spring rod 29) that implements a predetermined function of the chair (the object to be operated by the operation unit 295). Therefore, it is possible to conceal it appropriately.

  A lid (in the above embodiment, a fixed-type elbow rest 289) forms the uppermost surface of the armrest 15 (in the above embodiment, the upper surface of the elbow rest main body 301), and this lid 289 is an elbow support portion. Since it is a single member expanded to a size extending from 287 to the upper end 169 of the back support arm 151, the lid 289 can be easily attached and detached. In addition, since the lid body 289 can be integrally formed, the manufacturing cost can be suppressed and the number of parts can be reduced.

  The present invention is not limited to the embodiment described in detail above. For example, the backrest member is not limited to the back shell 205 of a resin molded product. The backrest member may be a curved thin plate back plate of a resin molded product or a metal molded product, and a cushion such as urethane sponge is attached to the front side of the rigid member (and the cushion is stretched). It may be one that is covered with the ground). Alternatively, a stretch fabric may be stretched on a rigid frame, and the backrest surface may be formed by the stretch fabric.

  In the above embodiment, the elbow pads 289 and 327 that are directly touched by the arm of the seated person and the elbow support part 287 that supports the load of the arm of the seated person are separate members. Does not interfere with molding.

  In the above embodiment, the elbow support portion 287 is extended from the upper end portion 169 of the back support arm 151, but the upper end of the back support arm extends above the height near the seated person's waist. In this case, the elbow support part is extended from the middle part (not the upper end part) of the back support arm.

  In the above embodiment, the backrest member 205 and the back support arm 151 that supports the backrest member 205 are separate members. However, the backrest member is fixed to the front side of the back support arm, or the backrest member Of course, the back support arm and the backrest member can be integrally formed as long as the condition that the back support arm is fixed to the back side is satisfied.

  In particular, various types of movable elbow rests 327 can be considered.

  The movable type elbow rest 327 shown in FIGS. 37 and 38 is an aspect in which an elbow rest main body 331 on which a seated person's arm is placed is slidable with respect to the elbow support portion 287 in the left-right direction. The elbow rest 327 is interposed between an attachment base 329 that is directly attached to the elbow support 287, an elbow rest body 331 that is a separate body from the attachment base 329, and the attachment base 329 and the elbow rest body 331. And a movable mechanism (not shown) (e.g., equivalent to the mechanism described in Japanese Patent Application Laid-Open No. 2010-063833), and the mounting base 329, the elbow rest main body 331, and the movable mechanism as an integrated unit. The elbow support 287 can be attached to and detached from the elbow support 287.

  The movable mechanism includes a slide rail structure that guides the movement of the elbow rest main body 331 relative to the mounting base 329 in the left-right direction, and a moderation for selectively stopping the elbow rest main body 331 at any one of a plurality of positions in the left-right direction. Including mechanisms. These slide rail structures, moderation mechanisms, and the like can be configured in the same manner as in known movable armrests.

  When the movable type elbow rest 327 is mounted on the elbow support 287, the elbow rest main body 331 is slid in the left-right direction as shown by a solid line and a two-dot chain line in FIG. It is possible to arrange in a position.

  The movable type elbow rest 327 shown in FIG. 39 and FIG. 40 is an aspect in which the elbow rest main body 331 on which the arm of the seated person is placed can turn substantially horizontally with respect to the elbow support portion 287. The elbow rest 327 is interposed between an attachment base 329 that is directly attached to the elbow support 287, an elbow rest body 331 that is a separate body from the attachment base 329, and the attachment base 329 and the elbow rest body 331. A movable mechanism (not shown) is provided, and the mounting base 329, the elbow pad main body 331, and the movable mechanism are integrated with each other so as to be attached to and detached from the elbow support portion 287.

  The movable mechanism includes a hinge structure that allows horizontal rotation with respect to the mounting base 329 of the elbow rest main body 331, a moderation mechanism for selectively stopping the elbow rest main body 331 at any one of a plurality of positions on the horizontal rotation path, and the like. Include. These hinge structures, moderation mechanisms, and the like can be configured in the same manner as in known movable armrests.

  When the movable type elbow rest 327 is mounted on the elbow support 287, the front end side of the elbow rest main body 331 is pivoted inwardly or outwardly as shown by a solid line and a two-dot chain line in FIG. It can be placed in any orientation desired by the person.

  The movable type elbow rest 327 shown in FIGS. 41 and 42 is an embodiment in which an elbow rest main body 331 on which a seated person's arm is placed can rotate substantially perpendicularly to the elbow support portion 287. The elbow rest 327 is interposed between an attachment base 329 that is directly attached to the elbow support 287, an elbow rest body 331 that is a separate body from the attachment base 329, and the attachment base 329 and the elbow rest body 331. A movable mechanism (not shown) is provided, and the mounting base 329, the elbow pad main body 331, and the movable mechanism are integrated with each other so as to be attached to and detached from the elbow support portion 287.

  The movable mechanism includes a hinge structure that allows vertical rotation of the elbow rest main body 331 relative to the mounting base 329, and a moderation mechanism that selectively stops the elbow rest main body 331 at any one of a plurality of positions on the vertical rotation trajectory, Alternatively, a lock mechanism for selectively fixing the elbow rest main body 331 to any one of a plurality of positions on the vertical rotation track is included. These hinge structure, moderation mechanism, lock mechanism, and the like can be configured in the same manner as in a known movable armrest.

  When the movable type elbow rest 327 is mounted on the elbow support 287, the front end side of the elbow rest main body 331 is turned up and down as shown by a solid line and a two-dot chain line in FIG. It is possible to arrange at an arbitrary inclination angle.

  In the said embodiment, although the standing part 161 of the elbow support part 287 and the back support arm 151 made | forms the side view reverse L-shape, it is not limited to such a shape. By separately providing a support column that supports the front end portion of the elbow support portion 287 from below, the elbow support portion 287, the upright portion 161, and the support column can be configured to form a side-reverse character shape. Alternatively, the elbow strut may rise upward from the left and right sides below the seat, and an elbow support portion extended in the front-rear direction may be provided at the upper end portion, and the elbow pads 327 and 289 may be attached on the elbow strut. In this case, the elbow strut and the elbow support part have a T-shaped aspect in side view.

  The function operated by the operation lever 295 as the operation unit is not limited to the back seat lifting function. The operation lever 295 may be used for operations such as a lock function for switching between prohibition / prohibition of the locking operation of the backrest 11.

  In the above embodiment, the wire 297 (and the tube 300) connected to the operation unit 295 is guided downward from the inner space of the elbow support unit 287 to the lower edge of the back shell 205 through the wire insertion space 298. Although it was intended to be drawn in the seven directions (below the seat support 5 and on the support base 3), the handling of the wire 297 is not limited to this. The wire 297 may be passed through the back support arm 151.

  By adopting the structure of the elbow rest according to the present invention, not only switching between the movable type and the fixed type becomes simple, but also to the elbow rest in which the size, hardness, material, material, etc. of the elbow rest main body are different. Can be easily replaced.

  In addition, what is shown in FIG. 43 to FIG. 46 is a modification of the movable type elbow rest 327 in which the elbow rest main body 331 is slidable along a predetermined locus, and the elbow support 287 that supports this. is there. 44 shows a state where the upper covering material 331y is removed, FIG. 45 shows a state where the lower plate 331x is removed, and FIG. 46 shows a state where the mounting base 329 is removed.

  In this modification, the elbow rest main body 331 is divided into, for example, a metal lower plate 331x and an upper covering material 331y made of resin, for example, which is fitted on the lower plate 331x, and slides on the lower plate 331x. A long hole 332 extending in the direction, that is, the front-rear direction is formed. A plurality of long holes 332 are provided, three in the illustrated example. Each long hole 332 penetrates the lower plate 331x in the vertical direction. The lower plate 331x slides on the surface of the mounting base 329.

  On the surface of the mounting base 329, the same number of sliders 330 protruding upward as the long holes 332 are provided. Each slider 330 is inserted into each elongated hole 332 of the lower plate 331x and constitutes a movable mechanism that guides the movement of the elbow rest main body 331 together with the elongated hole 332. The slider 330 has a hollow cylindrical shape inside. The inner space of the slider 330 extends downward and passes through the mounting base 329 in the vertical direction. A central portion of the mounting base 330 is provided with a substantially rectangular through window 329x that extends in the front-rear direction in plan view. Further, a square hole 329y and a round hole 329z are formed in front of the through window 329x.

  When attaching the mounting base 329 to the elbow support portion 287, the screw 307 is inserted into the screw insertion hole 336 of the contact portion 335 on the rear side of the mounting base 329, and this screw 307 is inserted into the nut hole 308 on the front side of the back support arm 151. Screw and tighten to fix. In addition, in a state where a bolt 317 serving as a tether is inserted into a round hole 329z formed on the front side of the mounting base 329, the bolt 317 is screwed and fastened to the front side of the elbow support portion 287 and fixed. When the attachment base 329 is attached to the elbow support portion 287, a part of the pressing plate 313 fits in the square hole 329y.

  In the inner space of the elbow support portion 287 in this modification, a nut portion 287x is fixed at a position overlapping the slider 330 of the mounting base 329 in plan view. A female thread is cut on the inner periphery of the nut portion 287x. A screw 331z for preventing the lower plate 331x from being detached from the mounting base 329 is screwed into the nut portion 287x. The screw 331z is inserted into the inner space of the slider 330 from above the lower plate 331x, and its shaft portion is screwed into the inner periphery of the nut portion 287x. However, it is not essential to provide the nut portion 287 x in the elbow support portion 287, and a female screw may be cut on the inner periphery of the slider 330 and the screw 331 z may be screwed to the slider 330.

  A moderation element 287y serving as an element of the moderation mechanism is disposed at the central portion of the internal space of the elbow support portion 287. The moderation element 287y has an upper surface formed in a substantially wave shape when viewed from the side, and is elastically biased upward by a spring or the like. The moderation element 287y is accommodated in the through window 329x of the attachment base 329, and can project and retract in the vertical direction within the through window 329x. On the downward surface of the lower plate 331x of the elbow rest main body 331, an engaged portion (not shown) in the form of a rack (toothed tooth) in which irregularities are continuously provided in the front-rear direction is formed in advance. By engaging the moderation element 287y at such a position, the elbow rest main body 331 is selectively stopped at any of a plurality of positions in the front-rear direction.

  Of course, it is also possible to attach a fixed-type elbow rest 289 to the elbow support 287 in this modification, and the attachment structure in that case is exactly the same as in the above embodiment. Even when the fixed-type elbow rest 289 is attached, the nut portion 287x and the moderation element 287y can be left as they are.

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

  The present invention can be used as an office chair used in, for example, an office.

151 ... Back support arm 161 ... Standing part 205 ... Backrest member 287 ... Elbow support part 341 ... Bottom surface of elbow support part

Claims (6)

A pair of back support arms are arranged on the left and right sides of the backrest, and an armrest extending in the front-rear direction is provided at a portion extending in the vertical direction in each back support arm, and a cavity is formed inside the armrest ,
The interior space having the armrest wraps up to a portion extending in the vertical direction of the back support arm, and the chair forms a cavity communicating with the interior space in the portion . A pair of back support arms are arranged on the left and right sides of the backrest, and an armrest extending in the front-rear direction is provided at a portion extending in the vertical direction in each back support arm, and a cavity is formed inside the armrest,
As an element of the armrest, it has an elbow support part that encloses an internal space that opens upward, and a member that becomes a lid that closes the opening of the elbow support part from above,
An operation part for operating a predetermined function of the chair on the side of the elbow support part and a transmission member or a transmission mechanism for transmitting an operation force applied to the operation part are housed .
The chair , wherein the lid forms an uppermost surface of an armrest, and the lid is a single member extended to a size extending from the elbow support to the upper end of the back support arm . As an element of the armrest, it has an elbow support part that encloses an internal space that opens upward, and a member that becomes a lid that closes the opening of the elbow support part from above,
Transmission member or claim 1 chair according to have achieved transmission mechanism for transmitting the operation section and the operation force applied to the operating portion for operating the predetermined function of the chair on the side of the elbow support. Inner space of the elbow supporting portion is over substantially the entire area of the front and rear dimensions of the elbow support, the lid also claim 2 or 3, wherein spans substantially the entire region of the opening to close the opening of the elbow supporting portion Chairs. The chair according to claim 2, wherein the inner space of the elbow support part reaches a portion extending in the vertical direction of the back support arm, and a cavity communicating with the inner space is formed in the portion. By inserting a transmission member or a transmission mechanism for transmitting an operation force applied to an operation unit for operating a predetermined function of the chair into the cavity formed in a portion extending in the vertical direction of the back support arm, The chair according to claim 3 or 5 , wherein the chair is guided downward along a portion extending in an up-down direction of the back support arm from an internal space of the support portion.

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