.200940006 第二行程調整機構40 内側端411 把柄42 擋止塊44 導銷46 椅背深度調整機構60 齒排結構62 行程控制裝置64 定位環66 栓銷41 外側端412 彈性件43 凸柱45 樞軸50 頂面61 擋止面63 第二調整桿65 凸輪67 八、 本案若有化學式時，請揭示最能顯示發明特徵化 學式：（無） 九、 發明說明： 【發明所屬之技術領域】 本發明係有關一種辦公椅雙行程椅背仰躺調整機 構，尤指一種辦公椅在藉由第一行程機構改變椅背傾斜 位置後，可再藉由第二行程調整機構使椅背再傾斜一角 φ 度位置，藉以避免習知第一行程機構藉一次操作即可達 成第一行程及第二行程傾斜角度所造成的危險性，達成 辦公椅椅背以雙行程分次調整傾斜角度之安全效果者。 【先前技術】 目前為提昇一座椅如辦公椅之使用功能及其舒適 度，常在座椅設計多種不同的調整功能，如椅扶手高低 調整機構、椅座高低調整機構、及椅座後傾調整機構、 椅背後傾調整機構、椅背深度調整機構或腰靠凸出調整 機構等；上述不同功能的調整機構都已有多種不同的結 構設計，其中在椅座或椅背調整機構方面，包含：中華 3 200940006 民國新型 M321261、M326807、M308687、M3281531、 M272463、M270739、M244008、M244006、 M244008，發明公告號1227118、新型公告號00480961、 00312709 、 00219466 、 00148174 、 00051473 、 0578518 、 00444555、306219、296582，中國新型 ZL99235672.5 及 美國發明US6,994,400等，其中，椅座高低調整機構或椅 背調整機構大部分係設置在椅座底面一底盤之主架體 (第一架體）的内部，再分別利用一控制桿由底盤向外 延伸，使控制桿之一端延伸至椅座底面之邊緣供坐者之 ❹ 手部操控如以手扳動該控制桿’另一端則連結至底盤内 部之椅座高低調整機構或椅背調整機構的相關控制件； 一般而言，椅座高低調整機構及椅背調整機構係分別利 用一控制桿操作，如其中一控制桿設在椅座底面之右側 邊緣供人以右手操控，而另一控制桿則設在椅座底面之 左側邊緣供人以左手操控。 目前辦公椅的使用除了基本坐靠功能外，仰躺功能 之需要性也日漸提高，對於經常性、長時間坐在辦公椅 上之工作者如電腦使用者而言’一辦公椅已被當作工作 椅、休息椅或休閒椅等多用途使用，故辦公椅之椅背的 ® 角度調整範圍就必須符合上述多用途之使用功能；又， 目前習知之椅背傾斜調整機構大部分都屬於一種單行程 之調整機構，也就是藉由一單行程調整機構以一次操作 即可同時達成第一行程之傾斜角度如向後傾斜約2〇度供 坐者以仰躺姿態作淺度休息，及第二行程之傾斜角度如 椅背從第一行程之20度傾斜角度再向後傾斜一適當角度 如約10度供坐者可進一步以較傾斜之仰躺姿態作深度休 息（椅背已向後調整傾斜30度）；然，上述之單行程調 整機構在操作使用時，坐者須自我控制以選定其所欲之 椅背傾斜角度，由於一般辦公椅之底座設有滾輪以可在 4 200940006 地面滑動移位，因此當坐者在操作單行程調整機構時， 因個人疏忽或失控而容易直接向後仰躺至第二行程之傾 斜角度，即椅背越過第一行程之約2〇度傾斜角度至 度f約30度，此時因向後仰躺角度過大 而谷易發生向後翻倒之危險；而本發明主要係利用 =次調整以分別控制第一行程與第二行程的椅背傾斜 角度，達成辦公椅椅背以雙行程分次調整傾斜角 全效果’藉以增進辦公椅椅之使用效率。 【發明内容】.200940006 Second stroke adjustment mechanism 40 Inner end 411 handle 42 Stop block 44 Guide pin 46 Back cover depth adjustment mechanism 60 Tooth row structure 62 Stroke control device 64 Positioning ring 66 Pin 41 Outer end 412 Elastic member 43 Post 45 Axis 50 Top surface 61 Stop surface 63 Second adjustment rod 65 Cam 67 8. If there is a chemical formula in this case, please disclose the chemical formula that best shows the characteristics of the invention: (None) 9. Description of the invention: [Technical Field of the Invention] The present invention The utility model relates to an office chair double-stroke backrest reclining adjustment mechanism, in particular to an office chair, after the tilting position of the seat back is changed by the first stroke mechanism, the seat back can be tilted by an angle φ by the second stroke adjusting mechanism. The position can be used to avoid the danger caused by the first stroke mechanism and the second stroke inclination angle by the first stroke mechanism, and the safety effect of adjusting the tilt angle by the double strokes of the office chair back is achieved. [Prior Art] At present, in order to improve the function and comfort of a seat such as an office chair, various adjustment functions of the seat design, such as the height adjustment mechanism of the armrest, the height adjustment mechanism of the seat, and the backrest of the seat are often used. The adjustment mechanism, the back tilt adjustment mechanism of the chair, the depth adjustment mechanism of the seat back or the lumbar protrusion adjustment mechanism, etc.; the adjustment mechanism of the above different functions has various structural designs, wherein the seat or the seat back adjustment mechanism includes : Zhonghua 3 200940006 New M321261, M326807, M308687, M3281531, M272463, M270739, M244008, M244006, M244008, invention announcement number 1227118, new announcement numbers 00480961, 00312709, 00219466, 00148174, 00051473, 0578518, 00444555, 306219, 296582, China's new ZL99235672.5 and the US invention US6,994,400, etc., wherein the seat height adjustment mechanism or the seat back adjustment mechanism is mostly disposed inside the main frame body (the first frame body) of the bottom surface of the seat base, and then respectively Extending from the chassis by a lever, extending one end of the lever to the bottom of the seat The edge is for the seat of the rider. The handle is controlled by the hand. The other end is connected to the seat height adjustment mechanism or the back control mechanism of the seat back adjustment mechanism; in general, the seat height adjustment The mechanism and the backrest adjustment mechanism are respectively operated by a control rod, such as one of the control rods disposed on the right side edge of the bottom surface of the seat for the right hand to operate, and the other control rod is disposed on the left side edge of the bottom surface of the seat for the person to Left hand control. At present, in addition to the basic seating function, the need for the reclining function is increasing. For a worker who is sitting on an office chair for a long time, such as a computer user, an office chair has been regarded as Work chairs, rest chairs or lounge chairs are used for a variety of purposes, so the angle adjustment range of the back of the office chair must conform to the above-mentioned multi-purpose function; in addition, most of the current chair back tilt adjustment mechanisms belong to a single type. The adjustment mechanism of the stroke, that is, the tilt angle of the first stroke can be simultaneously achieved by a single stroke adjustment mechanism, such as tilting back about 2 degrees for the rider to take a shallow rest in the reclining posture, and the second stroke The inclination angle is such that the back of the chair is inclined from the inclination angle of 20 degrees of the first stroke and then inclined backward by an appropriate angle, for example, about 10 degrees, for the seat to further rest in a more inclined reclining posture (the back of the seat has been adjusted backward by 30 degrees) However, when the single stroke adjustment mechanism described above is used, the rider must control himself to select the desired tilt angle of the seat back, because the base of the general office chair is set. The roller can be slidably displaced on the ground in 4200940006, so when the occupant is operating the single-stroke adjustment mechanism, it is easy to directly recline back to the inclination angle of the second stroke due to personal negligence or loss of control, that is, the back of the chair passes over the first stroke. About 2 degrees of inclination angle to degree f to about 30 degrees, at this time because the backward reclining angle is too large, the valley is prone to fall backwards; and the present invention mainly uses = secondary adjustment to control the first stroke and the second stroke respectively The tilt angle of the back of the chair is achieved by the double-stroke adjustment of the tilt angle of the office chair back to enhance the efficiency of the office chair. [Summary of the Invention]
仰躺要=乃在ΐ提供一種辦公椅雙行程椅背 =凋整機構’包含··一第一架體，其頂面係鎖固在辦 =椅坐的底面處，其底面連結一支撐腳架，其後端與一 第二架體對應樞接結合，其内部設有一第一 構供可調整椅背的傾斜位置，及/或一控 構：可調整椅座的高低位置；一第二架： 日隸接結合，其後端與辦公椅椅背鎖固結合， ^其底部設有-彈性裝置供可調整椅背Lying on the back = is providing an office chair with a double-stroke back = the finishing mechanism' contains a first frame, the top surface of which is locked at the bottom of the chair, and the bottom surface is connected to a supporting foot. The rear end of the frame is pivotally coupled to a second frame body, and the first portion is provided with a first inclined position for adjusting the back of the chair, and/or a control structure: the height position of the seat can be adjusted; Frame: The day is connected, the back end is combined with the back of the office chair, and the bottom is provided with elastic means for the adjustable seat back.
程？整機構，其係設置在第-架= 供可在第一行程機構改變椅背的傾斜位 $後/可使椅背再傾斜一角度範圍；其中，當坐 使！背向後傾斜-適當角度供坐者仰躺 度從第一二# 一f操作該第二行程調整機構以使斜傾角 果達成辦公椅祷背以兩行程分次調 背仰以於;椅雙行程椅 齒排結構及複數個擋止面，並藉由設置 5 •200940006 一行程控制裝置中之複數個定位環供可與齒排結構之凹 槽處對應卡合，及複數個凸輪供可與抵壓擋止面而對椅 背深度調整機構形成一固定定位效果；藉此，可配合需 要而將椅背向斜後方移動，以增進坐者的舒適性。 【實施方式】 為使本發明更加明確詳實，兹舉一較佳實施例並配 合下列圖示，將本發明之結構及其技術特徵詳述如後： 參考圖1〜4所示，其分別係本發明辦公椅雙行程 椅背仰躺機構一實施例之立體示意圖、立體組合圖、立 體組合之局部放大圖及立體分解示意圖。本發明辦公椅 雙行程椅背仰躺機構1係安裝在辦公椅座1〇的底面11上 使用’其一端與椅背13鎖固結合，其包含：一第一架體 20、一第二架體3〇及一第二行程調整機構4〇。 該第一架體20頂面係利用鎖固件與辦公椅坐1〇的底 面11鎖固結合，且其底面連結一支撐腳架12，並藉由一 樞軸50穿過第一架體20及第二架體3〇以對應樞接結合， 該第一架體20設有一第一行程機構21並藉由操作第一調Cheng? The whole mechanism, which is set in the first frame = for the first stroke mechanism to change the tilt position of the seat back $ after / can tilt the seat back an angle range; wherein, when sitting! Back-to-back tilt-appropriate angle for the seater's reclining degree to operate the second stroke adjustment mechanism from the first two #f, so that the oblique tilting fruit reaches the office chair prayer back with two strokes to adjust the back-up; a tooth row structure and a plurality of stop faces, and by providing a plurality of positioning rings in the 5:200940006 one-stroke control device for correspondingly engaging with the groove of the tooth row structure, and a plurality of cams are available The pressure stop surface forms a fixed positioning effect on the seat back depth adjusting mechanism; thereby, the seat back can be moved obliquely rearward to meet the need to improve the comfort of the seat. [Embodiment] In order to make the present invention more clear and detailed, the structure and technical features of the present invention will be described in detail as follows with reference to the following drawings: Referring to Figures 1 to 4, respectively A three-dimensional schematic diagram, a three-dimensional combination diagram, a partial enlarged view and a three-dimensional exploded view of an embodiment of the double-stroke backrest reclining mechanism of the office chair of the present invention. The double-stroke backrest reclining mechanism of the office chair of the present invention is mounted on the bottom surface 11 of the office chair 1 'with one end and the seat back 13 is locked and combined, and includes: a first frame 20 and a second frame The body 3〇 and a second stroke adjustment mechanism 4〇. The top surface of the first frame body 20 is locked and coupled with the bottom surface 11 of the office chair by a locking member, and the bottom surface thereof is coupled to a supporting foot frame 12, and passes through the first frame body 20 through a pivot 50 and The second frame body 3 is coupled by a pivotal connection, and the first frame body 20 is provided with a first stroke mechanism 21 and operated by the first adjustment
整桿211可使第二架體3〇以樞軸5〇為軸心極轉一適當角 度，22度，進而使對應連結在第二架體3〇上端的椅背13 可凋整呈一傾斜角度，及一高低控制機構22供可 座的高低位置。 π 該第二架體30其前端係與第一架體2〇對應樞接結 合，其後端與辦公椅椅背鎖固結合，且在其底部設 圖6〜10所示）如彈簧供可調整椅背傾 斜可設有一椅背深度調整機構 =了將向斜後方移動’該椅背深度調整機構肋， 下殼體組合形成的殼體結構，其頂面 61上§又有複數個齒排結構62及複數個擋止面昍，並藉由 6 .200940006 设置在第二架體30上之一行程控制裝置64以控制椅背深 度調整機構60之移動位置；本實施例之行程控制裝置 主要包含一第二調整桿65、複數個定位環66及複數個凸 輪67，其中，該第二調整桿65係套設複數個定位環及 複數，凸輪67，其穿設在第二架體3〇之第二開孔犯内， 並使複數個定位環66及複數個凸輪67藉由第二架體3〇上 之複數個第二開孔34對應穿過，且使該複數個定位環66 與齒排結構62之凹槽處對應活動卡合，將椅背深度調整 機構60調整至適當位置處，轉動該第二調整桿昍並同步 ❹ 帶動複數個凸輪66轉動，而使其凸輪面相對抵緊在播止 面63上並對椅背深度調整機構產生一固定定位效果。 s亥第一行程調整機構40係設置在第一架體2〇及第-架義之間，供可在第—行程機構21改變 = 位置後，可使椅背13再傾斜-角度範圍如職，本實= 例之第二行程調整機構4〇可包含一栓銷41，該栓銷41包 含一内側端411及一外侧端412，其係穿過第一架體2〇 之第一開孔23及第二架體30上相對應之左/右兩栓孔 31a、31b，該栓銷41之一内侧端41丨向外連接一把柄 〇 42，該栓銷41上套設一彈性件43如彈簧並藉由一擋止塊 44將彈性件43限制在一適當位置處，又該栓銷41配合第 一架體30之栓孔31a設有一可在該拴孔3ia内隨栓銷41 移動的凸柱45，又該把柄42上連結設有一導銷46對應並 穿過第二架體30之導孔32，使該導銷46可在該導孔32内 來回移動，藉此，當把柄42向外拉開而帶動栓銷μ向外 移動且同步帶動凸柱45向外移動並脫離第二架體3〇之栓 孔31a，同時栓銷41之外側端412脫離第二架體3〇之栓 孔31b，使第二架體30從第一行程之傾斜角度再向後可 再傾斜一角度範圍如1〇度而達成第二行程的傾斜效果， 又該第二行程可藉由該彈性裝置14 (如圖6〜10所示） 7 .200940006 之彈簧彈性自動回復，也就是使椅背 自動回復至第一行程的位置，这出抛、由第一仃程位置 程分次調整傾斜角度之安全效果。辦么椅椅背13以兩行 下般可，在其上、 =固件穿過該鎖固孔與辦二 機構工::=係=:^=:裝躺 在辦公椅座10的底面1!上，其一端與^ ^裝 =Γί辦公椅椅座10相對椅背13之的 參考圖7所示，其係本發明辦公椅雙行椅 ===上該=:士£ 座1。相對椅背13呈一第一行程之傾斜角椅椅 ❹ ，考，8所示，其係本發明辦公椅雙行程椅背仰躺 之另—使用狀態圖’該雙行程 的底面η上，於第一行程時椅=向； =-角度A，進-步在第二行程時使椅背13斜傾角度 從第一行程之傾斜角度A再向後傾斜一角度B位置。 μ t考圖9所示，其係本發明辦公椅雙行㈣背仰躺 機，1之又一使用狀態圖。當坐者利用雙行程分次調整 別控制第一行程與第二行程，辦公椅椅座1〇相對椅 青之呈一舒適、正確的角度位置，藉以避免習知第一 ^程機構藉一次操作即可達成第一行程及第二行程傾斜 角度所造成的危險性如後躺角度過大而向後翻倒，達成 辦公椅椅背13以兩行程分次調整傾斜角度之安全效果。 8 .200940006 參考圖10、11所示，其係本發明辦公椅雙行程椅背 仰躺機構1之又二使用狀態圖。該雙行程椅背仰躺機 1安裝在辦公椅座10的底面11上，其一端與椅背13鎖固 結合，藉由調整一椅背深度調整機構60可使椅背13向斜 後方移動如圖11之箭頭C所示，比對圖10與圖丨丨調整 刖、後的位置狀態，可增加辦公椅的乘坐或仰躺空間， 並可配合體型較大者或以仰躺方式的坐者，以增進坐 的舒適性。 以上所述僅為本發明的較佳實施例，對本發明而言 ❹ 僅是說明性的，而非限制性的，·本專業技術人員理解Γ 在本發明權利要求所限定的精神和範圍内可對其進行許 多改變，修改，甚至等效變更，但都將落入本發明的^ 護範圍内。 【圖式簡單說明】 圖1係本發明一實施例安裝在辦公椅上立體示意圖。 圖2係本發明一立體組合圖示意圖。 圖3係圖2之局部放大示意圖。 & 圖4係本發明一立體分解示意圖。 圖5係本發明之椅背深度調整機構之立體分解示意圖。 圖6係本發明之一使用狀態示意圖。 圖7係本發明之再一使用狀態（第一行程）示意圖。 圖8係本發明之另一使用狀態（第二行程）示意圖。 圖9，本發明之又一使用狀態（坐者呈躺仰）示意圖。 圖10係本發明之椅背深度調整機構之使用狀態示意圖。 圖11係本發明之椅背深度調整機構之又一使用狀態示意 圖。 【主要元件符號說明】 9 200940006 雙行程椅背仰躺機構 底面11 椅背13 第一架體20 第一調整桿211 第一開孔23 栓孔31a 導孔32 φ 第三開孔34 栓銷41 外侧端412 彈性件43 凸柱45 樞軸50 頂面61 擔止面63 第二調整桿65 ❹ 凸輪67 1 辦公椅座10 支撐腳架12 彈性裝置14 第一行程機構21 高低控制機構22 第二架體30 栓孔31b 第二開孔33 第二行程調整機構40 内側端411 把柄42 擋止塊44 導銷46 椅背深度調整機構60 齒排結構62 行程控制裝置64 定位環66The whole rod 211 can rotate the second frame body 3 with the pivot axis 5〇 as an axis to a proper angle of 22 degrees, so that the seat back 13 correspondingly connected to the upper end of the second frame body 3 can be inclined and inclined. The angle, and a high and low control mechanism 22 are provided for the high and low positions of the seat. π The front end of the second frame body 30 is pivotally coupled to the first frame body 2, and the rear end of the second frame body 30 is pivotally coupled with the back of the office chair, and is provided at the bottom thereof as shown in FIGS. 6-10. Adjusting the back of the seat back may be provided with a backrest depth adjusting mechanism = moving the reclining rearward of the backrest depth adjusting mechanism rib, and the lower casing is combined to form a housing structure, and the top surface 61 has a plurality of tooth rows The structure 62 and the plurality of stop faces are controlled by a stroke control device 64 disposed on the second frame 30 by 6.200940006 to control the moving position of the seat back depth adjusting mechanism 60; the stroke control device of the embodiment is mainly The second adjusting rod 65 includes a plurality of positioning rings 66 and a plurality of cams 67. The second adjusting rod 65 is sleeved with a plurality of positioning rings and a plurality of cams 67. The second adjusting rods 65 are disposed on the second frame body. The second opening hole is made, and the plurality of positioning rings 66 and the plurality of cams 67 are correspondingly passed through the plurality of second openings 34 of the second frame body 3, and the plurality of positioning rings 66 are The groove of the tooth row structure 62 corresponds to the active engagement, and the seat back depth adjustment mechanism 60 is adjusted At a suitable position to the rotation of the second adjusting rod and Xuan ❹ driven synchronous rotation of a plurality of cams 66, while it is relatively tightly against the cam surface and the effect of generating a fixedly positioned on the seat back depth adjusting mechanism companion stop surface 63. The first stroke adjustment mechanism 40 is disposed between the first frame body 2 and the first frame, so that the seat back 13 can be tilted again after the first stroke mechanism 21 is changed to the position. The second stroke adjustment mechanism 4 of the present embodiment can include a pin 41 that includes an inner end 411 and an outer end 412 that pass through the first opening 23 of the first frame 2 And the corresponding left/right two pin holes 31a, 31b of the second frame 30, one of the inner ends 41 of the pin 41 is connected outwardly to a handle 42, and the pin 41 is sleeved with an elastic member 43. The spring is restrained by a stop block 44 to the elastic member 43 at an appropriate position, and the pin 41 is fitted with the bolt hole 31a of the first frame body 30 to be movable with the pin 41 in the bore 3ia. The guide post 45 is further connected with a guide pin 46 and passes through the guide hole 32 of the second frame 30, so that the guide pin 46 can move back and forth in the guide hole 32, whereby the handle 42 is used. Pulling outwardly to drive the pin 51 to move outwardly and synchronously driving the stud 45 to move outward and disengage from the bolt hole 31a of the second frame body 3, while the outer end 412 of the pin 41 is disengaged from the second frame 3栓 of the bolt hole 31b, so that the second frame 30 can be tilted backward from the tilt angle of the first stroke by an angle range, for example, 1 degree, to achieve the tilting effect of the second stroke, and the second stroke can be The elastic device 14 (shown in Figures 6 to 10) 7 .200940006 spring elastic automatic recovery, that is, the seat back automatically returns to the position of the first stroke, which is thrown, and the tilt is adjusted by the first stroke position. Angle safety effect. The chair back 13 can be made in two rows, on which the = firmware passes through the locking hole and the second mechanism::=System=:^=: The bottom of the office chair 10 is placed on the bottom 1! Above, the end of the office chair seat 10 relative to the seat back 13 is shown in Fig. 7, which is the office chair of the present invention, double row chair ===上上=:士座1. The opposite seat back 13 is a tilting angle chair chair 第一 of the first stroke, as shown in the test 8, which is the other embodiment of the present invention, the double-stroke back of the chair is lying on the bottom surface η of the double stroke. During the first stroke, the chair = direction; = - the angle A, and the step-by-step tilting of the seat back 13 from the inclination angle A of the first stroke by an angle B position during the second stroke. μ t is shown in Fig. 9, which is a double-row (four) back reclining machine of the present invention, and another state diagram of use. When the occupant uses the two-stroke sub-adjustment to control the first stroke and the second stroke, the office chair seat has a comfortable and correct angular position relative to the chair blue, so as to avoid the first operation of the first-time mechanism. The danger caused by the first stroke and the second stroke inclination angle can be achieved, such as the back lie angle is too large and falls backwards, and the safety effect of adjusting the tilt angle by the two steps of the office chair back 13 is achieved. 8.200940006 Referring to Figures 10 and 11, it is a two-use state diagram of the double-stroke backrest reclining mechanism 1 of the office chair of the present invention. The double-stroke back reclining machine 1 is mounted on the bottom surface 11 of the office chair 10, and one end thereof is lockedly coupled with the seat back 13. By adjusting a back depth adjustment mechanism 60, the seat back 13 can be moved obliquely rearward. As shown by the arrow C in Fig. 11, the positional state of the office chair can be increased by adjusting the position of the rear and rear positions of Fig. 10 and Fig. 10, and can be matched with a larger person or a seater in a reclining manner. To enhance the comfort of sitting. The above is only the preferred embodiment of the present invention, and is intended to be illustrative only and not limiting, and the skilled person understands that within the spirit and scope defined by the claims of the present invention. Many changes, modifications, and even equivalents may be made thereto, all of which fall within the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an embodiment of the present invention installed on an office chair. 2 is a schematic view of a three-dimensional combination of the present invention. Figure 3 is a partial enlarged view of Figure 2. & Figure 4 is a perspective exploded view of the present invention. FIG. 5 is a perspective exploded view of the seat back depth adjusting mechanism of the present invention. Figure 6 is a schematic view showing the state of use of one of the present inventions. Fig. 7 is a schematic view showing still another use state (first stroke) of the present invention. Figure 8 is a schematic view of another state of use (second stroke) of the present invention. Fig. 9 is a schematic view showing still another use state of the present invention (the seater is lying down). Fig. 10 is a view showing the state of use of the seat back depth adjusting mechanism of the present invention. Fig. 11 is a view showing still another state of use of the seat back depth adjusting mechanism of the present invention. [Main component symbol description] 9 200940006 Double-stroke chair back reclining mechanism bottom surface 11 Chair back 13 First frame body 20 First adjustment lever 211 First opening hole 23 Bolt hole 31a Guide hole 32 φ Third opening hole Bolt 41 Outer end 412 Elastic member 43 Stud 45 Pivot 50 Top surface 61 Stretch surface 63 Second adjustment lever 65 凸轮 Cam 67 1 Office seat 10 Supporting foot frame 12 Elastic device 14 First stroke mechanism 21 Height control mechanism 22 Second Frame 30 Bolt hole 31b Second opening 33 Second stroke adjustment mechanism 40 Inner end 411 Handle 42 Stop block 44 Guide pin 46 Back depth adjustment mechanism 60 Tooth row structure 62 Stroke control device 64 Positioning ring 66