JP6618691B2

JP6618691B2 - Chair

Info

Publication number: JP6618691B2
Application number: JP2015053654A
Authority: JP
Inventors: 照護青木
Original assignee: 東海金属工業株式会社
Priority date: 2015-03-17
Filing date: 2015-03-17
Publication date: 2019-12-11
Anticipated expiration: 2035-03-17
Also published as: JP2016171920A

Description

本発明は、椅子に関する。より詳しくは、背もたれの後傾動作に連動して座を移動させる体重感応式の椅子に関する。 The present invention relates to a chair. More specifically, the present invention relates to a weight-sensitive chair that moves a seat in conjunction with a backward tilting motion of the backrest.

この種の椅子では、着座者の座り心地を向上させるため着座者の体の動きに合わせて背もたれ（背アーム）の後傾と連動して座面の後部を後傾移動させることが望ましい。特許文献１の椅子は、人が着座するための座面が設けられた着座部と、この着座部を支持するための座受け部と、座受け部を着座部の下面側から支持するためのベース部と、このベース部を下方から支持するための脚部と、人の背中の荷重を支持するための背もたれと、この背もたれに連結され、この背もたれの後傾動作に伴い回動可能に動作する背アームと、この背アームの後傾動作に伴い着座部を持ち上げるリンク部材とを備える。リンク部材は、着座部と背アームとベース部とを各々回動可能に連結する後リンク部と、後リンク部より前に配置され、着座部とベース部とを各々回動可能に連結する前リンク部とを備える。また後リンク部と前リンク部とによって、背アームの後傾時に、起立方向に回動されながら着座部の座面全体が後傾される。 In this type of chair, in order to improve the sitting comfort of the seated person, it is desirable to rearwardly move the rear part of the seating surface in conjunction with the backward tilting of the backrest (back arm) in accordance with the movement of the seated person's body. The chair of Patent Document 1 is a seat part provided with a seating surface for a person to sit on, a seat receiving part for supporting the seating part, and a seat receiving part for supporting the seat receiving part from the lower surface side of the seating part. A base part, a leg part for supporting the base part from below, a backrest for supporting a load on the back of a person, and a backrest connected to the backrest so that the backrest can be rotated in accordance with a backward tilting operation. And a link member that lifts the seat portion in accordance with the backward tilting operation of the back arm. The link member is disposed in front of the rear link portion and the rear link portion that rotatably connects the seat portion, the back arm, and the base portion, and before the link between the seat portion and the base portion is rotatably connected. A link portion. Further, when the back arm is tilted backward by the rear link portion and the front link portion, the entire seating surface of the seating portion is tilted backward while being rotated in the standing direction.

特開２０１２−１０９３８号公報JP 2012-10938 A

しかしながら、上記特許文献１の椅子では、人が着座して背アームに荷重をかけて後傾させる場合、座面全体が後傾すると同時に着座部の前側の座面が大きく上がっていた。そのため、その前側の座面に大腿部があたり、足への圧迫感が大きく座り心地が悪くなる恐れがあった。 However, in the chair of Patent Document 1, when a person sits and leans backward by applying a load to the back arm, the entire seating surface tilts backward, and at the same time the seating surface on the front side of the seating portion rises greatly. For this reason, the thigh hits against the front seat surface, and there is a fear that the feeling of pressure on the foot is large and the sitting comfort is deteriorated.

本発明は、上記の問題点を鑑みて創案されたものであり、本発明が解決しようとする課題は、座面の後側を後傾させる際に、座面の前側を大きく上げないで着座者の座り心地を向上することにある。 The present invention was devised in view of the above-mentioned problems, and the problem to be solved by the present invention is that when the rear side of the seating surface is tilted backward, the seating is performed without greatly raising the front side of the seating surface. Is to improve the sitting comfort of the elderly.

本発明の椅子は、人が着座するための座面が設けられた着座部と、この着座部の下面側に配置されて板状に形成され、着座部が取り付けられることにより上面側が覆われる座受け体と、座受け体の下方に配置されて、座受け体を支持するためのベース部とを備える。また椅子は、着座した人の背中からかかる荷重を支持するための背もたれと、この背もたれの後傾動作に連動して後傾動作する背アームとを備える。また椅子は、座受け体とベース部とを各々回動可能に連結する後リンク部材と、この後リンク部材よりも前側に配置されて、前記座受け体と前記ベース部とを相対的に離間する方向に移動可能に連結する前側連結部とを備える。また椅子は、背アームの後傾動作に抗して付勢する付勢手段とを備える。後リンク部材は、その上端側を座受け体に第一の後回動中心として回動可能に連結されて、その下端側をベース部に第一の後回動中心よりも後方を第二の後回動中心として回動可能に連結されている。前リンク部材は、その上端側を座受け体に第一の前回動中心として回動可能に連結されて、その下端側をベース部に第一の前回動中心よりも後方を第二の前回動中心として回動可能に連結されている。座受け体は、座受け体の前側を形成している座受け前部と、座受け体の後側を形成している座受け後部とで構成され、座受け前部と座受け後部とは、互いに隣接した境界を第一の後回動中心として互いに相対的に回動可能である。また座受け後部は、後リンク部材及び背アームと一体的に回動可能である。さらに背アームの後傾動作に伴い、座受け体が後リンク部材の各回動中心により回動されて、かつ、前側連結部によりベース部と座受け体とが互いに離間する方向に移動されながら、座受け後部、後リンク部材及び背アームは相対的な位置関係を維持した状態で一体的に回動され、さらに、座受け前部が上昇方向へ回動されて第一の後回動中心として座受け前部に対して座受け後部が相対的に下がる方向へ回動される。 The chair of the present invention is a seat part provided with a seating surface for a person to sit on, a seat disposed on the lower surface side of the seating part and formed in a plate shape, and the upper surface side is covered by attaching the seating part. A receiving body and a base part which is arrange | positioned under the seat receiving body and supports a seat receiving body are provided. The chair also includes a backrest for supporting a load applied from the back of a seated person, and a back arm that moves backward in conjunction with a backward tilting operation of the backrest. Further, the chair is disposed on the front side of the rear link member that rotatably couples the seat receiver and the base portion, and is relatively spaced apart from the seat receiver and the base portion. And a front connecting portion that is movably connected in the direction to be moved. The chair also includes urging means for urging against the backward tilting action of the back arm. The rear link member is pivotally connected to the seat receiving body with the upper end side as a first rear rotation center, and the lower end side is a second base portion with the lower end side behind the first rear rotation center. It is connected so as to be pivotable as a rear pivot center. The front link member is rotatably connected to the seat receiving body with the upper end side as a first front rotation center, and the lower end side is used as a base part and the second front rotation is performed behind the first front rotation center. As a center, it is connected so that rotation is possible. The seat receiver is composed of a seat front part that forms the front side of the seat receiver and a seat back part that forms the rear side of the seat receiver. The seat front part and the seat rear part are , They can be rotated relative to each other with the boundaries adjacent to each other as the first rear rotation center. Further, the rear portion of the seat receiver can be rotated integrally with the rear link member and the back arm. Further, with the backward tilting action of the back arm, the seat receiver is rotated by each rotation center of the rear link member, and the base portion and the seat receiver are moved away from each other by the front connecting portion, The rear portion of the seat receiver, the rear link member, and the back arm are integrally rotated while maintaining the relative positional relationship, and the front portion of the seat receiver is rotated in the upward direction to serve as the first rear rotation center. The seat receiving rear part is rotated in a direction to be relatively lowered with respect to the seat receiving front part.

この場合、背アームの後傾動作に伴い、座受け体が後リンク部材の各回動中心により回動されて、かつ、前側連結部によりベース部と座受け体とが互いに離間する方向に移動されながら、座受け後部、後リンク部材及び背アームは一体的に連結された状態で回動されるので、人が着座して背もたれに荷重をかけた際、体に密着しながら体に追従して傾くので座り心地が向上する。このとき、座受け前部が上昇方向へ回動され、第一の後回動中心として座受け前部に対して座受け後部が相対的に下がる方向へ回動されるため、座受け前部と座受け後部の前後別々の動きにより、座受け後部（座面）が下方移動（後傾）しても座受け部（座受け前部）の前側が上がりにくくなる。したがって、座受け部の前側で大腿部にあたる圧迫感を軽減できる。 In this case, as the back arm is tilted backward, the seat receiving body is rotated around each rotation center of the rear link member, and the base portion and the seat receiving body are moved away from each other by the front connecting portion. However, since the seat receiving rear part, the rear link member and the back arm are rotated in an integrally connected state, when a person is seated and a load is applied to the backrest, it follows the body while closely contacting the body. The seating comfort is improved because it tilts. At this time, the seat receiving front part is rotated in the upward direction, and the seat receiving front part is rotated in a direction in which the seat receiving rear part is lowered relative to the seat receiving front part as the first rear rotation center. And the back and rear movements of the rear part of the seat receiving part make it difficult for the front side of the seat receiving part (the seat receiving front part) to rise even if the seat receiving rear part (seat surface) moves downward (tilts backward). Accordingly, it is possible to reduce a feeling of pressure on the thigh on the front side of the seat receiving portion.

またこの椅子では、着座部は、座受け前部の上面に配置されて着座部の前側の座面を形成している前側座面を有し、背もたれの後傾動作を行っている状態では、この後傾動作を行わず荷重がかかっていない背もたれの起立時の状態よりも、前側座面の後端側が前側座面の前端側よりも相対的に上がった状態で配置されることが好ましい。この場合、座面の前側が大きく上昇することなく座面の後側が下がるため、大腿部を圧迫することを軽減し座り心地が向上する。 Further, in this chair, the seating portion has a front seat surface that is disposed on the upper surface of the seat receiving front portion and forms a seating surface on the front side of the seating portion, and in a state where the backrest is tilted backward, It is preferable that the rear end side of the front seat surface be positioned relatively higher than the front end side of the front seat surface, rather than a state where the backrest does not perform the rearward tilting operation and the load is not applied. In this case, the rear side of the seating surface is lowered without significantly raising the front side of the seating surface, so that the pressure on the thigh is reduced and the sitting comfort is improved.

またこの椅子では、好ましくは、前側連結部は、後リンク部材よりも前側に配置されて、座受け体とベース部とを各々回動可能に連結する前リンク部材である。この前リンク部材は、その上端側を座受け体に第一の前回動中心として回動可能に連結されて、その下端側をベース部に第一の前回動中心よりも後方を第二の前回動中心として回動可能に連結されている。また前リンク部材の上端側に配置された第一の前回動中心と、前リンク部材の下端側に配置された第二の前回動中心との間の距離よりも、後リンク部材の上端側に配置された第一の後回動中心と、後リンク部材の第二の後回動中心との間の距離の方が大きい。この場合、前リンク部材側の座受け体（座受け前部）の連結部分が、後リンク部材側の座受け体（座受け前部と座受け後部の境界）の連結部分よりも上がりにくくなり、座面の前端側が上がりにくくなるため、人が着座した際に足の大腿部への接触が軽減されて座り心地が向上する。 Moreover, in this chair, Preferably, a front side connection part is a front link member which is arrange | positioned ahead of a rear link member and connects a seat receiving body and a base part so that rotation is possible respectively. The front link member is rotatably connected to the seat receiving body with the upper end side as a first front rotation center, and the lower end side is used as a base portion and the rear of the first front rotation center is the second previous time. It is connected so as to be rotatable as a center of movement. Further, the distance between the first front rotation center disposed on the upper end side of the front link member and the second front rotation center disposed on the lower end side of the front link member is closer to the upper end side of the rear link member. The distance between the arranged first rear rotation center and the second rear rotation center of the rear link member is larger. In this case, the connecting part of the seat receiving body (the seat receiving front part) on the front link member side is less likely to rise than the connecting part of the seat receiving body (the boundary between the seat receiving front part and the seat receiving rear part) on the rear link member side. Since the front end side of the seating surface is difficult to rise, contact with the thigh of the foot is reduced when a person is seated, and the sitting comfort is improved.

またこの椅子では、後リンク部材は、弾性的に付勢するばね部材を連結するための後リンク連結部を備え、付勢手段は、ばね部材の一端側を後リンク連結部に回動可能に連結することが好ましい。この場合、後リンク部材を規制しながら一体的にスムーズに回動し、付勢手段によって背もたれが後傾状態から起立状態へ戻り易くなり、背もたれの起立時と背もたれの後傾時との相互の切り替えにおいて着座者に違和感を与えない。 Further, in this chair, the rear link member includes a rear link connecting portion for connecting a spring member that is elastically biased, and the biasing means can turn one end side of the spring member to the rear link connecting portion. It is preferable to connect. In this case, the rear link member is regulated and smoothly rotated integrally, and the backrest easily returns from the rearward tilted state to the standing state by the urging means, and the mutual relationship between the backrest standing and the backrest tilting backward Does not give a sense of incongruity to the seated person when switching.

本発明によれば、座面の後側を後傾させる際に、座面の前側を大きく上げないで着座者の座り心地を向上することができる。 According to the present invention, when the rear side of the seating surface is tilted backward, the sitting comfort of the seated person can be improved without greatly raising the front side of the seating surface.

本発明の一実施形態に係る椅子の斜視図である。It is a perspective view of the chair concerning one embodiment of the present invention. 図１に示される椅子のＡ−Ａ断面図である。It is AA sectional drawing of the chair shown by FIG. 図１及び図２に示される椅子を部分的に拡大して模式的に示した側面図である。FIG. 3 is a side view schematically showing the chair shown in FIGS. 1 and 2 partially enlarged. 図１に示される椅子の座受け体及びベース部の斜視図である。It is a perspective view of the seat receiver and base part of the chair shown in FIG. 図１に示される椅子のベース部及び背もたれの斜視図である。It is a perspective view of the base part and backrest of the chair shown by FIG. 図２に示される座受け体の下面側を部分的に拡大して示した斜視図である。It is the perspective view which expanded and showed the lower surface side of the seat receiving body shown by FIG. 図１に示される椅子を下方から見た斜視図である。It is the perspective view which looked at the chair shown by FIG. 1 from the downward direction. 図１に示される椅子の分解図である。FIG. 2 is an exploded view of the chair shown in FIG. 1. 図８に示されるベース部を拡大して示した分解図である。It is the exploded view which expanded and showed the base part shown by FIG.

本発明の一実施形態について説明する。本実施形態の椅子１は、一人掛け用の椅子であり例えば、事務用としてオフィス等で使用される。なお、各図において示される上下や前後左右の矢印は、椅子１における上下や前後左右を示している。 An embodiment of the present invention will be described. The chair 1 of this embodiment is a chair for one person, and is used in offices or the like for office work, for example. In addition, the up / down and front / rear / left / right arrows shown in each figure indicate the up / down, front / rear, left / right in the chair 1.

図１及び図２に示される椅子１は、人が着座するための座面４ａが設けられた着座部４と、この着座部４が取り付けられることにより上面側が覆われる座受け体８とを備える。また椅子１は、座受け体８の下方に配置されて、座受け体８を支持するためのベース部１０と、このベース部１０を下方から支える脚６を備える。また椅子１は、座受け体８とベース部材１０とを回動可能に連結する後リンク部材３０及び前リンク部材５０を備える。また椅子１は、着座者の背中からかかる荷重を支持するための背もたれ２と、この背もたれ２の後傾動作に連動して後傾動作する背アーム２０とを備える。また椅子１は、背アーム２０の後傾動作に抗して付勢するばね部材６０を備える。 The chair 1 shown in FIG.1 and FIG.2 is provided with the seat part 4 in which the seat surface 4a for a person to sit down was provided, and the seat receiving body 8 by which this seat part 4 is attached, and the upper surface side is covered. . The chair 1 includes a base portion 10 that is disposed below the seat receiving body 8 and supports the seat receiving body 8 and legs 6 that support the base portion 10 from below. Moreover, the chair 1 is provided with the rear link member 30 and the front link member 50 which connect the seat receiving body 8 and the base member 10 so that rotation is possible. The chair 1 also includes a backrest 2 for supporting a load applied from the back of the seated person, and a back arm 20 that performs a backward tilting operation in conjunction with a backward tilting operation of the backrest 2. The chair 1 also includes a spring member 60 that urges the back arm 20 against a backward tilting operation.

図１に示される着座部４は、発泡ウレタン等のクッション材で形成されており、平面視で、矩形状に形成された部位である。着座部４の座面４ａは、全体として略水平に配置されている。詳しくは、着座部４の座面４ａの中央部分は、図２に示すように前端側がやや下方に傾斜しており、後端側がやや上方に傾斜した状態で配置されている。着座部４は、図２及び図３に示すように裏面側に配置された座受け体８によって支持されている。着座部４は、その前側の座面を形成している前側座面４２と、着座部４の後側の座面を形成している後側座面４４とを備える。前側座面４２は、人が着座する際に主に大腿部に接触する部位である。後側座面４４は、人が着座したときに荷重がかかり易い部位であり、複数の凹部４０を有する。凹部４０は、背もたれ２の回動（揺動）動作により着座部４の前側座面４２と、後側座面４４との間で行われる曲げ動作をよりフレキシブルにするために設けられた凹みである。凹部４０は、図１に示すように着座部４の左右方向の一端側から他端側にかけて、帯状に形成されている。複数の凹部４０は、前後方向に並んで複数本（本実施形態では３本）配置されている。 The seating portion 4 shown in FIG. 1 is formed of a cushion material such as urethane foam, and is a portion formed in a rectangular shape in plan view. The seating surface 4a of the seating part 4 is disposed substantially horizontally as a whole. Specifically, as shown in FIG. 2, the central portion of the seating surface 4 a of the seating portion 4 is arranged with the front end side inclined slightly downward and the rear end side inclined slightly upward. As shown in FIGS. 2 and 3, the seat portion 4 is supported by a seat receiver 8 disposed on the back side. The seat portion 4 includes a front seat surface 42 that forms a front seat surface thereof, and a rear seat surface 44 that forms a rear seat surface of the seat portion 4. The front seat surface 42 is a part that mainly contacts the thigh when a person is seated. The rear seat surface 44 is a portion where a load is easily applied when a person is seated, and has a plurality of recesses 40. The recess 40 is a recess provided in order to make the bending operation performed between the front seat surface 42 and the rear seat surface 44 of the seating portion 4 more flexible by the pivoting (swinging) operation of the backrest 2. is there. As shown in FIG. 1, the recess 40 is formed in a band shape from one end side to the other end side of the seating portion 4 in the left-right direction. A plurality of recesses 40 (three in this embodiment) are arranged side by side in the front-rear direction.

図２に示される座受け体８は、着座部４を支持するための部位であり、平面視で矩形状に形成された板状の部位である。座受け体８は、着座部４の下面（裏面）側に配置されている。座受け体８は、座受け前部８２と、座受け後部８４と備える。 The seat receiver 8 shown in FIG. 2 is a part for supporting the seating part 4, and is a plate-like part formed in a rectangular shape in plan view. The seat receiver 8 is disposed on the lower surface (back surface) side of the seat portion 4. The seat receiving body 8 includes a seat receiving front part 82 and a seat receiving rear part 84.

座受け前部８２は、前側座面４２に対して裏面側に配置されている部位である。座受け前部８２は、平板状の部材である。座受け前部８２は、図２に示すようにその裏面側に後述する前リンク部材５０を回動可能に支持するための支持部８２ｄを備える。支持部８２ｄは、前リンク部材５０の上端側の形状に沿って、略湾曲状に形成されており、座受け前部８２の略中央に配置されている。座受け前部８２は、図４及び図８に示すように略中央部分に孔８２ａ、８２ｂが設けられている。孔８２ｂは、左右両側に一対設けられおり、前リンク部材５０の上端側を回動する前上回動部５２が外れないようにするためのストッパー５６が配置されている。孔８２ａは、一対の孔８２ｂの間の略中央に配置されており、その孔８２ａの前側の縁は、ストッパー５６の上面に設けられた係合部５６ａにより、係合されている。ストッパー５６の両側は、爪を有する一対の係合部５６ｂが設けられている。その係合部５６ｂによって、ストッパー５６の両側が座受け前部８２の裏面側に引っ掛けられて固定される。座受け前部８２の後端は、図８に示すように左右両側に左右方向に挿通可能に形成された一対の差込孔８２ｃが設けられている。一対の差込孔８２ｃは、後述する棒状の後上回動軸３３を通すための差込孔である。 The seat receiving front part 82 is a part arranged on the back side with respect to the front side seating surface 42. The seat receiving front part 82 is a flat member. As shown in FIG. 2, the seat receiving front portion 82 includes a support portion 82 d for rotatably supporting a front link member 50 described later on the back surface side thereof. The support portion 82d is formed in a substantially curved shape along the shape of the upper end side of the front link member 50, and is disposed at the approximate center of the seat receiving front portion 82. As shown in FIGS. 4 and 8, the seat receiving front portion 82 is provided with holes 82 a and 82 b in a substantially central portion. A pair of holes 82b are provided on both the left and right sides, and a stopper 56 is provided to prevent the front upper rotation portion 52 that rotates the upper end side of the front link member 50 from being removed. The hole 82 a is disposed at the approximate center between the pair of holes 82 b, and the front edge of the hole 82 a is engaged by an engaging portion 56 a provided on the upper surface of the stopper 56. On both sides of the stopper 56, a pair of engaging portions 56b having claws are provided. By the engaging portion 56b, both sides of the stopper 56 are hooked and fixed to the back side of the seat receiving front portion 82. As shown in FIG. 8, the rear end of the seat receiving front portion 82 is provided with a pair of insertion holes 82c formed so as to be inserted in the left and right sides. The pair of insertion holes 82c are insertion holes for passing a rod-shaped rear upper rotation shaft 33 described later.

座受け後部８４は、図２及び図３に示すように後側座面４４に対して裏面側に配置されている部位である。座受け後部８４は、左右方向に延びた平板状の部材である。座受け後部８４の略中央の左右両端側は、図８に示すように一対の孔８４ｂが設けられている。一対の孔８４ｂは、ビス等により背アーム２０に連結するために設けられた孔である。一対の孔８４ｂの内側は、一対の孔８４ａが設けられている。一対の孔８４ａは、ビス等により背アーム２０及び後リンク部材３０に連結するために設けられた孔である。一対の孔８４ａ、８４ｂへ、ビス等を挿通することにより、座受け後部８４（座受け体８）は、背アーム２０及び後リンク部材３０へ連結して固定される。座受け後部８４の前端の左右の両端側は、図４に示すように左右方向に差込ができる一対の差込孔８４ｃが設けられている。一対の差込孔８４ｃは、座受け後部８４の左右方向の内側が開放され、その外側が封鎖された筒状の差込孔である。一対の差込孔８４ｃは、図８に示すように各々座受け後部８４の前端側から一対突出した形状で形成されている。その一対の差込孔８４ｃと座受け前部８２の一対の差込孔８２ｃとへ、後上回動軸３３が各々差し込まれて回動可能に連結されている。その連結される際の配置は、図８に示すように座受け後部８４側の一対の差込孔８４ｃよりも、座受け前部８２側の一対の差込孔８２ｃの方が内側になるように配置される。そうすることで、座受け前部８２と座受け後部８４とは、図７に示すように互いに隣接した境界に配置された後上回動軸３３により第一の後回動中心３２ａとして相対的に回動可能になっている。 As shown in FIGS. 2 and 3, the seat receiving rear portion 84 is a portion disposed on the back surface side with respect to the rear seat surface 44. The seat receiving rear portion 84 is a flat plate-like member extending in the left-right direction. As shown in FIG. 8, a pair of holes 84b are provided on the left and right ends at the substantially center of the seat receiving rear portion 84. As shown in FIG. The pair of holes 84b are holes provided for connecting to the back arm 20 with screws or the like. A pair of holes 84a are provided inside the pair of holes 84b. The pair of holes 84a are holes provided to be connected to the back arm 20 and the rear link member 30 by screws or the like. By inserting a screw or the like into the pair of holes 84a and 84b, the seat receiving rear portion 84 (the seat receiving body 8) is connected and fixed to the back arm 20 and the rear link member 30. As shown in FIG. 4, a pair of insertion holes 84 c that can be inserted in the left-right direction are provided on the left and right ends of the front end of the seat receiving rear portion 84. The pair of insertion holes 84c are cylindrical insertion holes in which the inner side in the left-right direction of the seat receiving rear part 84 is opened and the outer side is sealed. As shown in FIG. 8, the pair of insertion holes 84 c are formed so as to protrude in pairs from the front end side of the seat receiving rear portion 84. The rear upper rotation shaft 33 is inserted into the pair of insertion holes 84c and the pair of insertion holes 82c of the seat receiving front portion 82, and is rotatably connected. As shown in FIG. 8, the paired insertion holes 82 c on the seat receiving front part 82 side are on the inner side than the pair of insertion holes 84 c on the seat receiving rear part 84 side. Placed in. By doing so, the seat receiving front part 82 and the seat receiving rear part 84 are relatively set as the first rear turning center 32a by the rear upper turning shaft 33 arranged at the boundary adjacent to each other as shown in FIG. Can be rotated.

ベース部１０は、図４に示すように上方が開放された箱状の部位である。ベース部１０は、図９に示すように底面１０ｘと、側面部１０ｙとを備える。底面１０ｘは、ベース部１０の下端側に配置された面の上面側を形成する部位である。底面１０ｘは、孔１０ｃを有しており、その孔１０ｃに脚６（脚柱部６６）が挿通されている。ベース部１０は、脚６が挿通した状態でベース部１０と脚６が連結されて固定されている。脚６は、図１及び図２に示すようにベース部１０を支持するための部位である。脚６は、複数本の棒状の骨格で構成される枝部６２と、中心に上下方向に柱状に形成されている脚柱部６６とを備える。脚柱部６６は、上端側がベース部１０に連結されている。脚柱部６６は、金属製の棒状の支柱部６６ａと、その支柱部６６ａを覆う脚柱カバー６６ｂとを備える。枝部６２は、脚柱部６６から複数方向に向けて輻射状に形成されており、各々の枝部６２の先端部は、キャスター６４が取り付けられている。 The base part 10 is a box-shaped part whose upper part is opened as shown in FIG. As shown in FIG. 9, the base portion 10 includes a bottom surface 10x and a side surface portion 10y. The bottom surface 10 x is a part that forms the upper surface side of the surface disposed on the lower end side of the base portion 10. The bottom surface 10x has a hole 10c, and the leg 6 (leg post 66) is inserted through the hole 10c. The base portion 10 is fixed by connecting the base portion 10 and the legs 6 with the legs 6 inserted. The leg 6 is a part for supporting the base portion 10 as shown in FIGS. 1 and 2. The leg 6 includes a branch portion 62 composed of a plurality of rod-like skeletons, and a leg column portion 66 formed in a column shape in the vertical direction at the center. The upper end side of the columnar part 66 is connected to the base part 10. The pedestal portion 66 includes a metal rod-shaped support portion 66a and a pedestal cover 66b that covers the support portion 66a. The branch part 62 is radially formed from the pillar part 66 in a plurality of directions, and a caster 64 is attached to the tip part of each branch part 62.

側面部１０ｙは、図９に示すようにベース部１０の左右の側に配置された面を形成する部位である。一対の側面部１０ｙは、図２に示すように前リンク部材５０及び後リンク部材３０の下端側と回動可能に連結されている。図９に示される一対の側面部１０ｙは、前リンク部材５０を回動可能にするための前下回動軸５１を挿通するための一対のベース部前孔１０ａと、後リンク部材３０を回動可能にするための後下回動軸３１を挿通するための一対のベース部後孔１０ｂとが設けられている。一対の側面部１０ｙの間には、図２に示すようにベース部１０を補強するためのベース部補強材１４が配置されている。 The side part 10y is a part which forms the surface arrange | positioned at the left-right side of the base part 10, as shown in FIG. As shown in FIG. 2, the pair of side surface portions 10 y is rotatably connected to the lower end sides of the front link member 50 and the rear link member 30. The pair of side surface portions 10y shown in FIG. 9 rotates the pair of base portion front holes 10a for inserting the front lower rotation shaft 51 for allowing the front link member 50 to turn and the rear link member 30. A pair of base portion rear holes 10b for inserting the rear lower rotation shaft 31 for enabling movement is provided. Between the pair of side surface portions 10y, a base portion reinforcing member 14 for reinforcing the base portion 10 is disposed as shown in FIG.

ベース部補強材１４は、図９に示すようにベース部１０の内部に沿って前後方向に板状に形成されている部材である。ベース部補強材１４の略中央は、図９に示すようにベース部１０の孔１０ｃと重なるようにして配置するための孔１４ｃが設けられている。ベース部補強材１４の後側は、図２に示すように後方に向けて谷折り山折りの順に曲げられて形成されて配置されている。そうすることで、ベース部補強材１４の後端側に略水平な面１４ａが形成されて配置されている。面１４ａは、図２及び図９に示すようにベース部１０の底面１０ｘから離間した状態で後端側に配置されており、ベース部１０の上端と略同じ高さになるように配置されている。面１４ａの上面側には、図２及び図９に示すように後リンク部材３０の回動（揺動）を止めるための後述する制止部材１２が接続して設けられている。 The base part reinforcing member 14 is a member formed in a plate shape in the front-rear direction along the inside of the base part 10 as shown in FIG. As shown in FIG. 9, a hole 14 c is provided in the approximate center of the base portion reinforcing member 14 so as to overlap the hole 10 c of the base portion 10. As shown in FIG. 2, the rear side of the base portion reinforcing member 14 is bent and formed in the order of valley fold and mountain fold toward the rear. By doing so, a substantially horizontal surface 14 a is formed and arranged on the rear end side of the base portion reinforcing member 14. 2 and 9, the surface 14 a is disposed on the rear end side in a state of being separated from the bottom surface 10 x of the base portion 10, and is disposed so as to be substantially the same height as the upper end of the base portion 10. Yes. As shown in FIGS. 2 and 9, a stop member 12 (described later) for stopping the rotation (swing) of the rear link member 30 is connected to the upper surface side of the surface 14a.

背アーム２０は、図２及び図３に示すようにベース部１０に対して後端側に配置されており、側面視で、略Ｌ字状に形成されている。背アーム２０の一端側（上端側）は、背もたれ２に連結されている。背アーム２０の他端側（下端側）は、後リンク部材３０と、座受け体８（座受け後部８４）とに連結されている。背もたれ２は、図２に示すように側面視で人の背面に沿うような湾曲状に形成されており、正面視で矩形状に形成された板状の部材である。図２及び図３に示される背もたれ２は、着座者が荷重をかける前面側に対して後面側は、背アーム２０に連結されて配置されている。背アーム２０の後面側の略中央で、左右に長細い略直方体状に形成されたブラケット２２を介して、背アーム２０にビス等により連結されている。 As shown in FIGS. 2 and 3, the back arm 20 is disposed on the rear end side with respect to the base portion 10, and is formed in a substantially L shape in a side view. One end side (upper end side) of the back arm 20 is connected to the backrest 2. The other end side (lower end side) of the back arm 20 is connected to the rear link member 30 and the seat receiving body 8 (the seat receiving rear portion 84). As shown in FIG. 2, the backrest 2 is a plate-like member that is formed in a curved shape along the back of the person in a side view and is formed in a rectangular shape in the front view. The backrest 2 shown in FIGS. 2 and 3 is connected to the back arm 20 on the rear side with respect to the front side on which the seated person applies a load. It is connected to the back arm 20 by a screw or the like through a bracket 22 formed in a substantially rectangular parallelepiped shape that is long on the left and right sides at the approximate center on the rear surface side of the back arm 20.

図８に示される背アーム２０の他端側（下端側）の上面側は、座受け後部８４（座受け体８）が連結される。座受け後部８４に設けられた一対の孔８４ａと、背アーム２０の前側に設けられた一対の孔２０ｂとへ各々ビスを挿通することで一体的に連結して固定される。また座受け後部８４に設けられた一対の孔８４ｂと、背アーム２０の前側で一対の孔２０ｄよりも左右方向で外側に設けられた一対の孔２０ｄとへ各々ビスを挿通することでも連結して固定される。またその一方で、背アーム２０の他端側の下面側は、後リンク部材３０が連結されている。 A seat receiving rear portion 84 (seat receiving body 8) is connected to the upper surface side of the other end side (lower end side) of the back arm 20 shown in FIG. The screws are inserted into the pair of holes 84a provided in the seat receiving rear portion 84 and the pair of holes 20b provided on the front side of the back arm 20 so as to be integrally connected and fixed. The pair of holes 84b provided in the seat receiving rear portion 84 and the pair of holes 20d provided on the front side of the back arm 20 and on the outer side in the left-right direction with respect to the pair of holes 20d are also connected by inserting screws. Fixed. On the other hand, the rear link member 30 is connected to the lower surface side of the other end side of the back arm 20.

後リンク部材３０は、図９に示すように左右両端側が下方へ向けて折り曲げられた板状の部材である。後リンク部材３０は、側面部３０ｙと、上面部３０ｘと備える。後リンク部材３０は、図３に示すようにその上端側が第一の後回動中心３２ａとして座受け体８に回動可能に連結される。後リンク部材３０は、その下端側が第一の後回動中心３２ａよりも後方を第二の後回動中心３４ａとしてベース部１０に回動可能に連結される。また後リク部材３０は、背アーム２０に連結されて固定されている。後リンク部材３０の上面側は、図３に示すように背アーム２０に連結されて固定されている。 As shown in FIG. 9, the rear link member 30 is a plate-like member whose left and right ends are bent downward. The rear link member 30 includes a side surface portion 30y and an upper surface portion 30x. As shown in FIG. 3, the upper end side of the rear link member 30 is rotatably connected to the seat receiving body 8 as a first rear rotation center 32a. The rear link member 30 is rotatably connected to the base portion 10 with the lower end side of the rear link member 30 as the second rear rotation center 34a behind the first rear rotation center 32a. The rear recoil member 30 is connected to and fixed to the back arm 20. The upper surface side of the rear link member 30 is connected and fixed to the back arm 20 as shown in FIG.

図９に示される側面部３０ｙは、後リンク部材３０の側面を形成している板状の部位である。側面部３０ｙの後側は、その上端に隣接して上面部３０ｘが配置されている。側面部３０ｙの前側は、上面部３０ｘの前端の位置から延設して突き出ている。側面部３０ｙは、第一の後回動中心３２ａとして回動可能にするための一対の後上回動孔３２と、第二の後回動中心３４ａとして回動可能するための一対の後下回動孔３４と、後上回動孔３２と後下回動孔３４との間に配置されて、後述するばね部材６０を連結する棒状の軸３５を取り付けるための一対の長孔３６を備える。長孔３６は、後方に膨らむ略円弧状に形成された孔である。長孔３６に挿通された軸３５は、その軸３５の中央にばね部材６０を回動可能に連結して配置されている。なお、軸３５は、本発明の「後リンク連結部」に相当する。 The side surface portion 30y shown in FIG. 9 is a plate-like portion forming the side surface of the rear link member 30. On the rear side of the side surface portion 30y, an upper surface portion 30x is disposed adjacent to the upper end thereof. The front side of the side surface portion 30y protrudes from the position of the front end of the upper surface portion 30x. The side surface portion 30y has a pair of rear upper rotation holes 32 for enabling rotation as the first rear rotation center 32a and a pair of rear lower portions for enabling rotation as the second rear rotation center 34a. A pivot hole 34 is disposed between the rear upper pivot hole 32 and the rear lower pivot hole 34, and includes a pair of elongated holes 36 for attaching a rod-shaped shaft 35 that connects a spring member 60 described later. . The long hole 36 is a hole formed in a substantially arc shape that swells rearward. The shaft 35 inserted through the long hole 36 is disposed at the center of the shaft 35 with a spring member 60 rotatably connected thereto. The shaft 35 corresponds to the “rear link connecting portion” of the present invention.

図４及び図５に示される一対の側面部３０ｙの突き出た前側の上端側は、棒状に形成された金属製の後上回動軸３３を一対の後上回動孔３２に各々挿通させて回動可能に配置されている。後上回動軸３３は、前述した座受け前部８２と座受け後部８４とを連結して第一の後回動中心３２ａとして回動可能にするためのものである。後上回動軸３３は、図９に示すように後リンク部材３０の両端に、回動を容易にするための一対の軸受３３ａを介して取り付けられる。軸受３３ａは、円状の縁を有した輪状の部材である。後上回動軸３３は、図８に示すように左右方向の内側から外側にかけて、座受け前部８２の後端側に設けられている一対の差込孔８２ｃ、一対の後上回動孔３２、座受け後部８４の前端側で左右方向の両端に設けられた一対の差込孔８４ｃの順に回動可能に差し込まれて取り付けられる。 4 and 5, the upper upper side of the protruding front side of the pair of side surface portions 30y is inserted into the pair of rear upper rotation holes 32 through a metal rear upper rotation shaft 33 formed in a bar shape. It is arrange | positioned so that rotation is possible. The rear upper rotation shaft 33 is for connecting the above-described seat receiving front portion 82 and the seat receiving rear portion 84 so as to be rotatable as the first rear rotation center 32a. As shown in FIG. 9, the rear upper turning shaft 33 is attached to both ends of the rear link member 30 via a pair of bearings 33a for facilitating the turning. The bearing 33a is a ring-shaped member having a circular edge. As shown in FIG. 8, the rear upper rotation shaft 33 includes a pair of insertion holes 82 c and a pair of rear upper rotation holes provided on the rear end side of the seat receiving front portion 82 from the inner side to the outer side in the left-right direction. 32, a pair of insertion holes 84c provided at both ends in the left-right direction on the front end side of the seat receiving rear portion 84 are inserted so as to be turnable in order.

図８及び図９に示される一対の側面部３０ｙの突き出た前側の下端側は、棒状に形成された金属製の後下回動軸３１を一対の後下回動孔３４に挿通させ、ベース部１０の一対のベース部後孔１０ｂを挿通させて回動可能に連結した状態で配置されている。図９に示される後下回動軸３１は、後リンク部材３０の両端に、回動を容易にするための一対の軸受３１ａを介して取り付けられている。軸受３１ａは、円状の縁を有した輪状の部材である。 8 and FIG. 9, the lower end of the front side from which the pair of side surface portions 30y protrudes is inserted into the pair of rear lower rotation holes 34 by inserting a metal rear lower rotation shaft 31 formed in a rod shape into the base. The pair of base part rear holes 10b of the part 10 are inserted and arranged so as to be pivotably connected. The rear lower rotation shaft 31 shown in FIG. 9 is attached to both ends of the rear link member 30 via a pair of bearings 31a for facilitating the rotation. The bearing 31a is a ring-shaped member having a circular edge.

上面部３０ｘは、図２及び図６に示すようにその下面側（裏面側）に制止部材１２に接触して制止させるための板状の制止接触部３７が設けられている。制止接触部３７は、上面部３０ｘ（後リンク部材３０）の下面側（裏面側）に溶接等で一体的に接続されている。制止接触部３７は、背もたれ２（背アーム２０）の起立状態のとき、制止部材１２に接触して背もたれ２を制止させている。制止部材１２は、図２に示すように断面略逆Ｕ字状に形成されている。制止部材１２は、図９に示すようにベース部１０に配置された面１４ａの略中央に配置されて接続される制止部材本体１２ａと、その制止部材本体１２ａの上面側から後面側にかけて覆われる制止接触部１２ｂと、制止部材本体１２ａと制止接触部１２ｂとをビス等により固定するための孔１２ｃとを備える。制止接触部１２ｂの上面側は、背もたれ２が後傾状態のときに接触させて制止するために設けられた部位である。制止接触部１２ｂの後面側は、背もたれ２が起立状態のときに接触させて制止するために設けられた部位である。背もたれ２の後傾状態では、図２に示すように後リンク部材３０（上面部３０ｘ）の下面側の前端部分が、制止接触部１２ｂと接触して制止される。 As shown in FIGS. 2 and 6, the upper surface portion 30 x is provided with a plate-like restraining contact portion 37 for contacting and restraining the restraining member 12 on the lower surface side (back surface side). The restraining contact portion 37 is integrally connected to the lower surface side (back surface side) of the upper surface portion 30x (rear link member 30) by welding or the like. The restraining contact portion 37 contacts the restraining member 12 and restrains the backrest 2 when the backrest 2 (back arm 20) is standing. As shown in FIG. 2, the restraining member 12 has a substantially inverted U-shaped cross section. As shown in FIG. 9, the restraining member 12 is covered from the upper surface side to the rear surface side of the restraining member main body 12a that is disposed and connected to the center of the surface 14a disposed on the base portion 10, and is covered. A stop contact portion 12b, and a hole 12c for fixing the stop member main body 12a and the stop contact portion 12b with screws or the like are provided. The upper surface side of the restraining contact portion 12b is a portion provided for contacting and restraining the backrest 2 when the backrest 2 is tilted backward. The rear surface side of the restraining contact portion 12b is a portion provided for contacting and restraining when the backrest 2 is standing. In the rearward tilt state of the backrest 2, as shown in FIG. 2, the front end portion on the lower surface side of the rear link member 30 (upper surface portion 30x) comes into contact with the restraining contact portion 12b and is restrained.

またその一方で、上面部３０ｘは、その後側に設けられた一対の孔３０ｂと、背アーム２０の後側に設けられた一対の孔２０ｃとへ各々ビス等を挿通することで一体的に連結して固定される。上面部３０ｘは、その前側に設けられた一対の孔３０ａと、背アーム２０の前側に設けられた一対の孔２０ｂとへ各々ビス等を挿通することで一体的に連結して固定される。そうすることで、上面部３０ｘは、前述した座受け後部８４の一対の孔８４ａと、背アーム２０の一対の孔２０ｂと、後リンク部材３０の一対の３０ａとが、上からこの順で、上面側から３つの部材にビスが挿通されて一体的に連結される。そうすることで、背アーム２０が座受け後部８４（座受け部８）後リンク部材３０の間に挟まれた状態で連結される。したがって、座受け後部８４は、後リンク部材３０及び背アーム２０に一体的に連結された状態で回動できる。 On the other hand, the upper surface portion 30x is integrally connected by inserting screws or the like into a pair of holes 30b provided on the rear side and a pair of holes 20c provided on the rear side of the back arm 20. Fixed. The upper surface portion 30x is integrally connected and fixed by inserting screws or the like into a pair of holes 30a provided on the front side thereof and a pair of holes 20b provided on the front side of the back arm 20. By doing so, the upper surface portion 30x includes the pair of holes 84a of the seat receiving rear portion 84, the pair of holes 20b of the back arm 20, and the pair of 30a of the rear link member 30 in this order from above. Screws are inserted through the three members from the upper surface side and integrally connected. By doing so, the back arm 20 is connected in a state of being sandwiched between the seat receiving rear portion 84 (the seat receiving portion 8) and the rear link member 30. Therefore, the seat receiving rear portion 84 can be rotated in a state of being integrally connected to the rear link member 30 and the back arm 20.

後リンク部材３０及び背アーム２０の下面側（裏面側）は、図２に示すように背アームカバー２４が配置されている。背アームカバー２４は、図８に示すようにその後端側に設けられた複数（本実施形態では３つ）の係合爪２４ｂとで係合されている。その係合爪２４ｂに後リンク部材３０が係合された状態で、背アームカバー２４の前端側に設けられた一対の孔２４ａと、背アーム２０の最も前端側に設けられた一対の孔２０ａとにビスを挿入して一体的に連結することによって固定される。このようにして、図９で示される背アームカバー２４の前端側と後端側とが各々連結されることで、後リンク部材３０と背アームカバー２４とが、背アーム２０を間に挟んだ状態で固定される。 As shown in FIG. 2, a back arm cover 24 is disposed on the lower surface side (back surface side) of the rear link member 30 and the back arm 20. As shown in FIG. 8, the back arm cover 24 is engaged with a plurality (three in this embodiment) of engaging claws 24b provided on the rear end side. In a state where the rear link member 30 is engaged with the engaging claw 24b, a pair of holes 24a provided on the front end side of the back arm cover 24 and a pair of holes 20a provided on the most front end side of the back arm 20 are provided. It is fixed by inserting a screw into and connecting together. In this manner, the front end side and the rear end side of the back arm cover 24 shown in FIG. 9 are connected to each other, so that the rear link member 30 and the back arm cover 24 sandwich the back arm 20 therebetween. Fixed in state.

前リンク部材５０は、図９に示すようにその下端側の一部が切り欠かれ、矩形状のやや厚みのある板状の部材である。前リンク部材５０の上端側は、図２及び図３に示すように後述する後リンク部材３０よりも前側に配置されている。前リンク部材５０の上端側は、座受け体８に第一の前回動中心５２ａとして回動可能に連結される。前リンク部材５０の下端側は、第一の前回動中心５２ａよりも後方に配置された第二の前回動中心５４ａとしてベース部１０に回動可能に連結される。前リンク部材５０は、第一の前回動中心５２ａとして回動可能にするための前上回動部５２と、第二の前回動中心５４ａとして回動可能にするための前下回動孔５４とを備える。 As shown in FIG. 9, the front link member 50 is a rectangular plate member with a part of the lower end side cut out and having a slightly thicker shape. As shown in FIGS. 2 and 3, the upper end side of the front link member 50 is disposed on the front side of the rear link member 30 described later. The upper end side of the front link member 50 is rotatably connected to the seat receiver 8 as the first front rotation center 52a. The lower end side of the front link member 50 is rotatably connected to the base portion 10 as a second front rotation center 54a disposed rearward of the first front rotation center 52a. The front link member 50 has a front upper rotation part 52 for enabling rotation as a first front rotation center 52a, and a front lower rotation hole 54 for enabling rotation as a second front rotation center 54a. With.

図２に示される前リンク部材５０の上端側に配置された前上回動部５２は、座受け部８（座受け前部８２）と回動可能に連結されている。前上回動部５２は、その外周が側面視で略円弧状に形成されている。その連結される際は、前上回動部５２の位置がずれないようにするためのストッパー５６が設けられている。ストッパー５６は、その前面側を前上回動部５２の面の形状に沿って湾曲された柱状に形成された部材である。ストッパー５６の上面側は、座受け前部８２の上面側から係合するための係合部５６ａが設けられている。前上回動部５２は、座受け部８とストッパー５６との間に挟まれた状態で回動可能に配置されている。前リンク部材５０の下端側は、棒状に形成された金属製の前下回動軸５１を一対の前下回動孔５４に挿通させ、さらにベース部１０の一対のベース部前孔１０ａに挿通させて配置することで、回動できる。前下回動軸５１は、その前下回動軸５１の中央に後で詳述するばね部材６０を回動可能に連結して配置されている。 The front upper turning portion 52 disposed on the upper end side of the front link member 50 shown in FIG. 2 is rotatably connected to the seat receiving portion 8 (the seat receiving front portion 82). The outer periphery of the front upper turning part 52 is formed in a substantially arc shape in a side view. When the connection is made, a stopper 56 is provided to prevent the position of the front upper rotation part 52 from shifting. The stopper 56 is a member formed in the shape of a column whose front side is curved along the shape of the surface of the front upper rotation portion 52. On the upper surface side of the stopper 56, an engaging portion 56a for engaging from the upper surface side of the seat receiving front portion 82 is provided. The front upper turning portion 52 is rotatably arranged in a state of being sandwiched between the seat receiving portion 8 and the stopper 56. The lower end side of the front link member 50 is inserted through a pair of front lower rotation holes 54 through a pair of front lower rotation shafts 54 made of a metal and is further inserted into a pair of base portion front holes 10 a of the base portion 10. It can be rotated by arranging it. The front lower rotation shaft 51 is disposed at the center of the front lower rotation shaft 51 by rotatably connecting a spring member 60 described in detail later.

ばね部材６０は、図９に示すように金属線を円筒状に巻いたコイルばねである。ばね部材６０の両端は、伸縮方向に延設された引っ掛け部６０ａ、６０ｂを有する。ばね部材６０の一端側の引っ掛け部６０ａは、図６に示すようにばね部材６０の前端側を前下回動軸５１に連結するための前連結部６１に係止されている。ばね部材６０の他端側の引っ掛け部６０ｂは、ばね部材６０の後端側を軸３５に連結するための後連結部６３に係止されている。前連結部６１は、筒状の部位を有する部材であり、略中央に筒状の部位の長手方向に対して垂直方向に延設された板状の部位を有して形成されている部材である。後連結部６３は、筒状の部位を有する部材であり、略中央に筒状の部位の長手方向に対して垂直方向に延設された板状の部位を有して形成されている部材である。前連結部６１の延設された板状の部位は、ばね部材６０の前端側に連結されており、後連結部６３の延設された板状の部位は、ばね部材６０の後端側に連結されている。軸３５は、後連結部６３を介してばね部材６０が回動可能に取り付けられた状態で、一対の長孔３６の上側に各々差し込まれる。その差し込まれた状態で軸３５は、各長孔３６の円弧状の形状に沿って下方へ摺動させて、各長孔３６の最も下側に移動したとき、固定される。そうすることで、背アーム２０の後傾動作に抗して、ばね部材６０が前後方向に付勢することが可能な状態で配置される。このようにして、ばね部材６０は、前後に前連結部６１と後連結部６３とで各軸に回動可能に連結されており、背アーム２０の起立時と後傾動作との交互の動作に応じてばね部材６０が前後方向に伸縮可能に配置される。なお、ばね部材６０は、本発明の「付勢手段」に相当する。 The spring member 60 is a coil spring obtained by winding a metal wire in a cylindrical shape as shown in FIG. Both ends of the spring member 60 have hook portions 60a and 60b extending in the extending and contracting direction. The hook portion 60 a on one end side of the spring member 60 is engaged with a front connection portion 61 for connecting the front end side of the spring member 60 to the front lower rotation shaft 51 as shown in FIG. 6. The hook portion 60 b on the other end side of the spring member 60 is locked to a rear connection portion 63 for connecting the rear end side of the spring member 60 to the shaft 35. The front connecting portion 61 is a member having a cylindrical portion, and is a member formed to have a plate-like portion extending in a direction perpendicular to the longitudinal direction of the cylindrical portion at the center. is there. The rear connecting portion 63 is a member having a cylindrical portion, and is a member formed to have a plate-like portion extending in a direction perpendicular to the longitudinal direction of the cylindrical portion at the center. is there. The extended plate-like portion of the front connecting portion 61 is connected to the front end side of the spring member 60, and the extended plate-like portion of the rear connecting portion 63 is connected to the rear end side of the spring member 60. It is connected. The shaft 35 is inserted into the upper side of the pair of long holes 36 in a state where the spring member 60 is rotatably attached via the rear connecting portion 63. In the inserted state, the shaft 35 slides downward along the arcuate shape of each long hole 36 and is fixed when moved to the lowermost side of each long hole 36. By doing so, the spring member 60 is disposed in a state in which the spring member 60 can be urged in the front-rear direction against the backward tilting operation of the back arm 20. In this way, the spring member 60 is connected to the respective axes by the front connecting portion 61 and the rear connecting portion 63 so as to be able to rotate back and forth, and the alternate operation of the back arm 20 when the back arm 20 is raised and the backward tilting operation is performed. Accordingly, the spring member 60 is arranged to be extendable in the front-rear direction. The spring member 60 corresponds to the “biasing means” of the present invention.

次に、背もたれ２の起立時の状態と、背もたれ２の後傾時の状態とにおける位置関係と回動機構について詳細を説明する。図２及び図３に示される椅子１は、実線により背もたれ２が起立時の状態を示し、想像線により背もたれ２の後傾時（後）の状態を示す。座受け後部８４は、後リンク部材３０及び背アーム２０に一体的に連結された状態で回動するとき、背アーム２０の後傾動作に伴い、座受け体８が後リンク部材３０及び前リンク部材５０の各回動中心により回動される。その回動をしつつ、座受け後部８４、後リンク部材３０及び背アーム２０は、相対的に位置関係を維持しながら別部材が一体的に組み合わされて連結された状態で回動される。さらに、座受け前部８２が上昇方向へ回動されて、第一の後回動中心３２ａとして座受け前部８２に対して座受け後部８４が相対的に下がる方向へ回動される。 Next, the positional relationship and the turning mechanism in the state when the backrest 2 stands and the state when the backrest 2 is tilted backward will be described in detail. The chair 1 shown in FIG. 2 and FIG. 3 shows a state when the backrest 2 stands up by a solid line, and shows a state when the backrest 2 is tilted backward (rear) by an imaginary line. When the seat receiving rear portion 84 rotates in a state of being integrally connected to the rear link member 30 and the back arm 20, the seat receiving body 8 moves to the rear link member 30 and the front link along with the backward tilting operation of the back arm 20. The member 50 is rotated by each rotation center. While rotating, the seat receiving rear portion 84, the rear link member 30, and the back arm 20 are rotated in a state where other members are integrally combined and connected while maintaining a relative positional relationship. Further, the seat receiver front portion 82 is rotated in the upward direction, and the seat receiver rear portion 84 is rotated relative to the seat receiver front portion 82 as the first rear rotation center 32a.

図２及び図３に示される座受け後部８４の後端側は、背もたれ２の起立時において、第一の後回動中心３２ａよりも高い位置で制止接触部１２ｂの後面側に接触して制止されており、座受け前部８２に対して上方へ向けて屈曲した状態で配置されている。このとき、座受け前部８２は、略水平状態となっているため、座受け後部８４の後端側の上面は、座受け前部８２よりも上方へ上がった状態で配置されている。座受け後部８４の後端側は、背もたれ２の後傾開始から、最も後傾した状態になるまでに、下方に向けて回動される。その回動によって下方に移動され、座受け後部８４が背もたれ２が最も後傾した状態（後リンク部材３０が制止部材１２の上面側に配置されている制止接触部１２ｂに接触した状態）で座受け前部８２と同様に略水平状態になる。この場合、着座部４の後側座面４４は、背もたれ２の起立時においてその座面が略水平状態に配置されているのに対し、背もたれ２が最も後傾した状態のときにおいてその座面が後傾した状態で配置される。 2 and 3, the rear end side of the seat receiving rear portion 84 comes into contact with the rear surface side of the restraining contact portion 12b at a position higher than the first rear turning center 32a when the backrest 2 stands up. It is arranged in a state bent upward with respect to the seat receiving front part 82. At this time, since the seat receiving front part 82 is in a substantially horizontal state, the upper surface on the rear end side of the seat receiving rear part 84 is arranged in a state of being raised upward from the seat receiving front part 82. The rear end side of the seat receiving rear portion 84 is rotated downward from the start of the rearward tilting of the backrest 2 to the most backward tilted state. As a result of the rotation, the seat receiving rear portion 84 is seated in a state where the backrest 2 is inclined most backward (the rear link member 30 is in contact with the restraining contact portion 12b disposed on the upper surface side of the restraining member 12). As in the case of the receiving front portion 82, it becomes substantially horizontal. In this case, the rear seating surface 44 of the seating portion 4 is arranged in a substantially horizontal state when the backrest 2 stands, whereas the seating surface when the backrest 2 is tilted most backward. Are arranged in a tilted state.

図２及び図３に示されるこの回動において前リンク部材５０の上端側に配置された第一の前回動中心５２ａと、前リンク部材５０の下端側に配置された第二の前回動中心５４ａとの間の距離Ｌ１よりも、後リンク部材３０の上端側に配置された第一の後回動中心３２ａと、後リンク部材３０の第二の後回動中心３４ａとの間の距離Ｌ２の方が大きくなっている。前リンク部材５０の第一の前回動中心５２ａと前リンク部材５０の第二の前回動中心５４ａとを結んだ線分と、水平方向との傾斜角度αと、後リンク部材３０の第一の前回動中心５２ａと後リンク部材３０の第二の後回動中心３４ａとを結んだ線分と、水平方向との傾斜角度βとは、略同じ角度である。傾斜角度αと傾斜角度βとは、背もたれ２の起立時の状態で４０°〜６０°程度に配置されており、背もたれ２の後傾動作（後傾開始時を含む）の状態で、４０°〜８０°程度に配置される。そのため、背もたれ２の起立時の状態と、背もたれ２の後傾時の状態とを比較して第一の後回動中心３２ａの高さ変位Ｈ２と、第一の前回動中心５２ａの高さ変位Ｈ１とを比較して、変位Ｈ２の方が大きくなる。即ち、着座部４において、背もたれ２（背アーム２０）の後傾動作を行っている状態では、背もたれ２の後傾動作を行っていない背もたれ２の起立時の状態よりも、座受け前部８２（着座部４の前側座面４２）の後端側が座受け前部８２の前端側よりも相対的に上がった状態で配置される。またこのとき背もたれ２の起立時の状態よりも、背もたれ２の後傾動作を行っている状態の第一の前回動中心５２ａ及び第一の後回動中心３２ａの位置は、後側に配置される。 2 and 3, the first front rotation center 52a disposed on the upper end side of the front link member 50 and the second front rotation center 54a disposed on the lower end side of the front link member 50 in this rotation. The distance L2 between the first rear rotation center 32a disposed on the upper end side of the rear link member 30 and the second rear rotation center 34a of the rear link member 30 is greater than the distance L1 between Is getting bigger. The line segment connecting the first front rotation center 52a of the front link member 50 and the second front rotation center 54a of the front link member 50, the inclination angle α with the horizontal direction, and the first link of the rear link member 30 The line segment connecting the front rotation center 52a and the second rear rotation center 34a of the rear link member 30 and the inclination angle β between the horizontal direction and the horizontal direction are substantially the same angle. The tilt angle α and the tilt angle β are arranged at about 40 ° to 60 ° when the backrest 2 is standing, and 40 ° when the backrest 2 is tilted backward (including when the backrest starts). It is arranged at about ~ 80 °. Therefore, the height displacement H2 of the first rear rotation center 32a and the height displacement of the first front rotation center 52a are compared between the standing state of the backrest 2 and the rearward tilting state of the backrest 2. Compared with H1, the displacement H2 is larger. That is, in the state where the backrest 2 (back arm 20) is performing the backward tilting operation in the seating portion 4, the seat receiving front portion 82 is greater than the state of the backrest 2 that is not performing the backward tilting operation of the backrest 2. The rear end side (the front seating surface 42 of the seating portion 4) is disposed in a state where it is relatively higher than the front end side of the seat receiving front portion 82. Further, at this time, the positions of the first front rotation center 52a and the first rear rotation center 32a in the state in which the backrest 2 is performing the backward tilting operation are arranged on the rear side rather than the state in which the backrest 2 stands. The

本実施形態は、以下のような作用効果を有する。本実施形態の椅子１において、座受け体８は、座受け体８の前側を形成している座受け前部８２と、座受け体８の後側を形成している座受け後部８４とを備える。また座受け前部８２と座受け後部８４とは、互いに隣接した境界を第一の後回動中心３２ａとして互いに相対的に回動可能である。また座受け後部８４は、後リンク部材３０及び背アーム２０と一体的に回動可能である。さらに背アーム２０の後傾動作に伴い、座受け体８が後リンク部材３０の各回動中心により回動されて、かつ、前側連結部によりベース部１０と座受け体８とが互いに離間する方向に移動される。さらに、このとき移動されながら、座受け後部８４、後リンク部材３０及び背アーム２０は相対的な位置関係を維持した状態で一体的に回動され、さらに、座受け前部８２が上昇方向へ回動されて、第一の後回動中心３２ａとして座受け前部８２に対して座受け後部８４が相対的に下がる方向へ回動される。 The present embodiment has the following operational effects. In the chair 1 of the present embodiment, the seat receiver 8 includes a seat receiver front part 82 that forms the front side of the seat receiver 8 and a seat receiver rear part 84 that forms the rear side of the seat receiver 8. Prepare. Further, the seat receiving front part 82 and the seat receiving rear part 84 are rotatable relative to each other with a boundary adjacent to each other as a first rear turning center 32a. The seat receiving rear portion 84 can rotate integrally with the rear link member 30 and the back arm 20. Further, in accordance with the backward tilting operation of the back arm 20, the seat receiving body 8 is rotated about each rotation center of the rear link member 30, and the base portion 10 and the seat receiving body 8 are separated from each other by the front side connecting portion. Moved to. Further, while being moved at this time, the seat receiving rear portion 84, the rear link member 30 and the back arm 20 are integrally rotated while maintaining the relative positional relationship, and further, the seat receiving front portion 82 is moved upward. As a result, the seat receiving rear portion 84 is rotated relative to the seat receiving front portion 82 as the first rear rotating center 32a.

そうすることで、座受け後部８４は、背アーム２０の後傾動作に伴い、座受け体８が後リンク部材３０の各回動中心により回動されて、かつ、前側連結部によりベース部１０と座受け体８とが互いに離間する方向に移動される。さらに、このとき移動されながら、座受け後部８４、後リンク部材３０及び背アーム２０は一体的に連結された状態で回動されるので、人が着座して背もたれ２に荷重をかけた際、体に密着しながら体に追従した動きで座り心地が向上する。また座受け前部８２が上昇方向へ回動され、第一の後回動中心３２ａとして座受け前部８２に対して座受け後部８４が相対的に下がる方向へ回動されるため、座受け前部８２と座受け後部８４の前後別々の動きにより、座受け後部８４（座面）が下方移動（後傾）しても座受け部８（座受け前部８２）の前側が上がりにくくなる。したがって、人が着座した際に座受け部８の前側があたって大腿部を圧迫しにくくなる。 By doing so, the seat receiving rear portion 84 is rotated by the respective rotation centers of the rear link member 30 in accordance with the backward tilting operation of the back arm 20, and the base connecting portion 8 and the base portion 10 by the front connecting portion. The seat receiver 8 is moved away from each other. Further, while being moved at this time, the seat receiving rear portion 84, the rear link member 30 and the back arm 20 are rotated in an integrally connected state, so when a person is seated and a load is applied to the backrest 2, Sitting comfort is improved by movement that follows the body while closely contacting the body. Further, the seat receiver front portion 82 is rotated in the upward direction, and the seat receiver rear portion 84 is rotated in the direction of lowering relative to the seat receiver front portion 82 as the first rear rotation center 32a. By the front and rear movements of the front portion 82 and the seat receiving rear portion 84, the front side of the seat receiving portion 8 (the seat receiving front portion 82) is hardly raised even if the seat receiving rear portion 84 (seat surface) moves downward (tilts backward). . Therefore, when a person is seated, the front side of the seat receiving portion 8 hits and it becomes difficult to press the thigh.

またこの椅子１では、着座部４は、座受け前部８２の上面に配置されて着座部４の前側の座面を形成している前側座面４２を有し、背もたれ２の後傾動作を行っている状態では、この後傾動作を行わず荷重がかかっていない背もたれ２の起立時の状態よりも、前側座面４２の後端側が前側座面４２の前端側よりも相対的に上がった状態で配置される。そうすることで、座面の前側が大きく上昇することなく座面の後側が下がるため、人が着座した際に、大腿部を圧迫することがなく座り心地が向上する。 Moreover, in this chair 1, the seating part 4 has the front side seating surface 42 which is arrange | positioned on the upper surface of the seat receiving front part 82, and forms the seating surface of the front side of the seating part 4, and performs back tilting motion of the backrest 2 In the running state, the rear end side of the front seat surface 42 is relatively higher than the front end side of the front seat surface 42, as compared to the standing state of the backrest 2 in which the rearward tilting operation is not performed and no load is applied. Arranged in a state. By doing so, the rear side of the seating surface is lowered without significantly raising the front side of the seating surface, so that when a person is seated, the thigh is not compressed and the sitting comfort is improved.

またこの椅子１では、前側連結部は、後リンク部材３０よりも前側に配置されて、座受け体８とベース部１０とを各々回動可能に連結する前リンク部材５０である。この前リンク部材５０は、その上端側を座受け体８に第一の前回動中心５２ａとして回動可能に連結されて、その下端側をベース部１０に第一の前回動中心５２ａよりも後方を第二の前回動中心５４ａとして回動可能に連結されている。前リンク部材５０の上端側に配置された第一の前回動中心５２ａと、前リンク部材５０の下端側に配置された第二の前回動中心５４ａとの間の距離Ｌ１よりも、後リンク部材３０の上端側に配置された第一の後回動中心３２ａと、後リンク部材３０の第二の後回動中心３４ａとの間の距離Ｌ２の方が大きい。そうすることで、前リンク部材５０側の座受け体８（座受け前部８２）の連結部分が、後リンク部材３０側の座受け体８（座受け前部８２と座受け後部８４の境界）の連結部分よりも上がりにくくなり、座面の前側が上がりにくくなるため、人が着座した際に足の大腿部への接触が軽減されて座り心地が向上する。 Moreover, in this chair 1, a front side connection part is the front link member 50 which is arrange | positioned ahead of the rear link member 30, and connects the seat receiving body 8 and the base part 10 so that rotation is possible respectively. The front link member 50 is pivotally connected to the seat receiving body 8 with the upper end side thereof as a first front rotation center 52a, and the lower end side of the front link member 50 is behind the first front rotation center 52a. Are connected so as to be rotatable about a second front rotation center 54a. The rear link member is larger than the distance L1 between the first front rotation center 52a disposed on the upper end side of the front link member 50 and the second front rotation center 54a disposed on the lower end side of the front link member 50. The distance L2 between the first rear rotation center 32a disposed on the upper end side of the 30 and the second rear rotation center 34a of the rear link member 30 is larger. By doing so, the connecting portion of the seat receiving body 8 (the seat receiving front part 82) on the front link member 50 side is the boundary between the seat receiving body 8 (the seat receiving front part 82 and the seat receiving rear part 84) on the rear link member 30 side. ) And the front side of the seating surface is less likely to rise, so that when a person is seated, contact with the thighs of the foot is reduced and seating comfort is improved.

またこの椅子１では、後リンク部材３０は、弾性的に付勢するばね部材６０を連結するための軸３５を備え、ばね部材６０は、その一端側を軸３５に回動可能に連結される。そうすることで、後リンク部材３０を規制しながら一体的にスムーズに回動し、ばね部材６０によって背もたれ２が後傾状態から起立状態へ戻り易くなり、背もたれ２の起立時と背もたれ２の後傾時との相互の切り替えにおいて着座者に違和感を与えない。 Further, in the chair 1, the rear link member 30 includes a shaft 35 for connecting a spring member 60 that is elastically biased, and the spring member 60 is rotatably connected to the shaft 35 at one end thereof. . By doing so, the rear link member 30 is regulated and smoothly rotated integrally. The spring member 60 makes it easy for the backrest 2 to return from the rearward tilted state to the upright state, and when the backrest 2 stands up and behind the backrest 2. It does not give a sense of incongruity to the seated person when switching between the tilted times

またこの椅子１では、ばね部材６０は、その一端側が後リンク部材３０に配置された軸３５と、他端側が前リンク部材５０に配置された前下回動軸５１とに各々回動可能に連結される。そうすることで、ばね部材６０の連結部位を前下回動軸５１以外に設ける必要がなく、部品点数の削減になる。 Further, in the chair 1, the spring member 60 is rotatable about a shaft 35 arranged at one end side on the rear link member 30 and a front lower turning shaft 51 arranged at the other end side on the front link member 50. Connected. By doing so, it is not necessary to provide the connection part of the spring member 60 other than the front lower rotating shaft 51, and the number of parts is reduced.

本実施形態の椅子は、上述した実施形態に限定されるものではなく他の形態でも実施できる。本実施形態では、椅子１は、事務用の椅子に適用したがこれに限られるものではない。他の種類や用途の椅子に適用してもよい。 The chair of this embodiment is not limited to the above-described embodiment, and can be implemented in other forms. In this embodiment, although the chair 1 was applied to the office chair, it is not restricted to this. You may apply to the chair of another kind and use.

また本実施形態の背もたれ２は、背アーム２０とは別部材として連結して適用したがこれに限られるものでない。背もたれ２と背アーム２０とを一体的にして同じ部材として形成してもよい。 Moreover, although the backrest 2 of this embodiment was connected and applied as a separate member from the back arm 20, it is not restricted to this. The backrest 2 and the back arm 20 may be integrally formed as the same member.

また本実施形態のばね部材６０の一端側が後リンク部材３０に配置された軸３５へ、他端側が前リンク部材に配置された前下回動軸５１へ回動可能に連結したがこれに限られるものではない。他端側を別の部位に連結して付勢可能にしてもよい。 In addition, one end side of the spring member 60 of this embodiment is rotatably connected to the shaft 35 disposed on the rear link member 30 and the other end side is pivotally connected to the front lower rotation shaft 51 disposed on the front link member. It is not something that can be done. The other end side may be connected to another part to enable energization.

また本実施形態の前側連結部は、前リンク部材５０としたがこれに限られるものではない。前リンク部材５０を設けないでベース部１０と座受け体８とを直接連結して前側連結部としてもよい。この場合、ベース部１０又は座受け体８のどちらか一方に長孔を設け、長孔を設けない他方に円柱状（棒状）の連結軸を設けて、この長孔内で円柱状の連結軸が移動可能に連結してもよい。即ち、この前側連結部は、後リンク部材よりも前側に配置されて、座受け体８とベース部１０とを相対的に離間する方向に移動可能に連結される。さらにこの場合、図３に示される背アーム２０の後傾状態となる前の実線部分の前リンク部材５０の第一の前回動中心５２ａと、背アーム２０の後傾状態となった後の想像線部分の前リンク部材５２の第一の前回動中心５２ａとの軌道に沿った円弧状の距離と同等の長さでこの長孔を設けてもよく、又はこの軌道位置にこの長孔を設けてもよい。その際の長孔は、連結軸が入る大きさであればよく、円弧状でもよいし、直線状（円柱状の連結軸よりやや幅広にすることが好ましい。）にしてもよい。 Moreover, although the front side connection part of this embodiment was made into the front link member 50, it is not restricted to this. Without providing the front link member 50, the base part 10 and the seat support 8 may be directly connected to form a front side connection part. In this case, either one of the base portion 10 and the seat support 8 is provided with a long hole, and the other without the long hole is provided with a columnar (rod-shaped) connecting shaft. May be movably connected. That is, this front side connection part is arrange | positioned ahead of a rear link member, and is connected so that the seat receiving body 8 and the base part 10 can move to the direction which spaces apart relatively. Further, in this case, the first forward rotation center 52a of the front link member 50 in the solid line part before the back arm 20 shown in FIG. The long hole may be provided with a length equivalent to the arc-shaped distance along the track with the first front rotation center 52a of the front link member 52 of the line portion, or the long hole is provided at the track position. May be. In this case, the long hole may have a size that allows the connecting shaft to be inserted, and may have an arc shape or a linear shape (preferably slightly wider than the cylindrical connecting shaft).

１椅子
２背もたれ
４着座部
４ａ座面
６脚
８座受け体
１０ベース部
２０背アーム
３０後リンク部材
３２ａ第一の後回動中心
３４ａ第二の後回動中心
３５軸
４２前側座面
４４後側座面
５０前リンク部材
５２ａ第一の前回動中心
５４ａ第二の前回動中心
６０ばね部材
８２座受け前部
８４座受け後部
Ｌ１距離
Ｌ２距離
DESCRIPTION OF SYMBOLS 1 Chair 2 Backrest 4 Seating part 4a Seat surface 6 Leg 8 Seat receiving body 10 Base part 20 Back arm 30 Rear link member 32a First rear rotation center 34a Second rear rotation center 35 Axis 42 Front seat surface 44 Rear Side seat surface 50 Front link member 52a First front rotation center 54a Second front rotation center 60 Spring member 82 Seat receiving front portion 84 Seat receiving rear portion L1 Distance L2 Distance

Claims

A seating portion provided with a seating surface for a person to sit on;
A seat receiver which is disposed on the lower surface side of the seating portion and formed in a plate shape, and the upper surface side is covered by attaching the seating portion;
A base portion disposed below the seat support to support the seat support;
A backrest to support the load applied from the seated person's back,
A back arm that tilts backward in conjunction with the backward tilting motion of the backrest;
A rear link member for rotatably connecting the seat receiver and the base part;
A front side connecting portion that is arranged on the front side of the rear link member and connects the seat receiving body and the base portion so as to be relatively spaced apart from each other;
A chair provided with biasing means for biasing against the backward tilting motion of the back arm,
The rear link member is pivotally connected to the seat receiving body with an upper end side thereof as a first rear rotation center, and a lower end side of the rear link member is rearward of the base portion with respect to the first rear rotation center. Is pivotally connected around the second rear rotation center,
The first rear rotation center is shifted rearward and upward from the standing position of the back arm as the back arm is tilted backward.
The seat receiving body includes a seat receiving front portion forming a front side of the seat receiving body,
And a rear seat portion forming the rear side of the seat receiver,
The seat receiving front portion and the seat receiving rear portion are rotatable relative to each other with the boundary adjacent to each other as the first rear rotation center,
The seat receiving rear portion is rotatable integrally with the rear link member and the back arm,
With the back tilting operation of the back arm, the seat receiving body is rotated by the respective rotation centers of the rear link member, and the base portion and the seat receiving body are separated from each other by the front connecting portion. The seat receiving rear part, the rear link member, and the back arm are integrally rotated while maintaining the relative positional relationship while the seat receiving front part rotates in the upward direction. The seat receiving rear part is rotated relative to the seat receiving front part as the first rear turning center in a direction of lowering including the rear end part of the seat receiving rear part,
The rear link member includes a rear link connecting portion for connecting an elastically biased spring member,
The biasing means is a chair that rotatably connects one end side of the spring member to the rear link connecting portion .

The seating portion has a front seat surface that is disposed on the upper surface of the seat receiving front portion and forms a front seating surface of the seating portion,
In the state of performing the backward tilting operation of the backrest, the rear end side of the front seating surface is more than the front end side of the front seating surface than the state of standing the backrest that is not subjected to the backward tilting operation and is not loaded. The chair according to claim 1, which is also arranged in a relatively raised state.

The front side connecting portion is a front link member that is disposed on the front side of the rear link member and rotatably connects the seat receiver and the base portion.
The front link member is rotatably connected to the seat receiving body with the upper end side as a first front rotation center, and the lower end side of the front link member is connected to the base portion behind the first front rotation center. It is connected so as to be able to rotate as the second front rotation center,
The rear link member is more than the distance between the first front rotation center disposed on the upper end side of the front link member and the second front rotation center disposed on the lower end side of the front link member. The chair according to claim 1 or 2, wherein a distance between the first rear rotation center disposed on the upper end side of the rear link member and the second rear rotation center of the rear link member is larger. .