201139828 六、發明說明： 【發明所屬之技術領域】 本發明是關於：「用來輔助門之開閉」的門緩閉器（ door check)等所使用的壓缸裝置。 【先前技術】 以下的門緩閉器已被大眾所知悉：藉由將彈簧緩衝器 等的壓缸裝置鏈接結合於鉸鏈門（hinged door)，對門的 開閉作用彈力、衰減力，而使門自動的關閉、或調整其關 閉速度，此外，將門保持於開啓位置。傳統上，就利用該 種彈簧緩衝器等之壓缸裝置的門緩閉器而言，有著如專利 文獻1所記載的裝置。 專利文獻1所記載的門緩閉器，是藉由將「使壓縮線 圈彈簧的彈力朝作動活塞桿之伸長方向作用」的彈簧緩衝 器，鏈接結合於鉸鏈門的門與門框之間，而對應於門的開 度，當門位於關閉位置附近時，賦予關閉方向的力量，此 外，當門位於全開位置附近時，則將門保持於開啓位置。 [專利文獻Π日本特開2008-2 124號公報 【發明內容】 [發明欲解決之課題] 然而，在上述專利文獻1所記載的技術中，具有以下 的問題：在彈簧緩衝器位於被收縮至最短之中間位置的場 合中’將導致產生較強的彈力。因此，即使在門位於開關 -5- 201139828 閉位置的中間時，也將形成「作用彈力（指彈力 )」的情形，以致在「欲將門保持於開關閉位置 的場合中存在問題。 本發明的目的是提供一種：解決上述問題點 置。 [解決課題之手段] 爲了解決上述的課題，本發明，是具備下述 缸裝置：壓缸，該壓缸已封入有作動流體；和活 塞是可滑動地嵌裝於該壓缸內；和活塞桿，該活 於該活塞，且延伸至前述壓缸的外部：及彈簧構 簧構件被設於前述壓缸內，當前述活塞桿從前述 的長度爲特定長度以上時，對該前述活塞桿作用 未達特定長度時，則不對前述活塞桿作用彈力， :前述彈簧機構具有：外周離合溝，該外周離合 前述活塞桿的外周；和內周離合溝，該外周離合 前述外周離合溝，且被設於前述壓缸的內周側； 手段，該離合器手段在當前述活塞桿從前述壓缸 度爲特定長度以上時，與前述外周離合溝卡合且 述活塞桿而被固定於軸方向上，並且能相對於前 移動於軸方向上，當前述活塞桿從前述壓缸突出 達特定長度時，與前述內周離合溝卡合且相對於 而被固定於軸方向上，並且能相對於前述活塞桿 軸方向上；及彈簧手段，該彈簧手段是用來彈推 發生作用 之中間」 的壓缸裝 構件的壓 塞，該活 塞桿連結 件，該彈 壓缸突出 彈力，當 其特徵爲 溝被設於 溝是面向 和離合器 突出的長 相對於前 述壓缸而 的長度未 前述壓缸 而移動於 前述離合 -6- 201139828 器手段；前述離合器手段包含：複數個凸輪構件，該複數 個凸輪構件是在卡合於前述外周離合溝及前述內周離合溝 的至少其中一個的狀態下，被插入設有前述內周離合溝之 前述壓缸側的內周面與前述活塞桿的外周面之間；及保持 構件’該保持構件是用來將該凸輪構件保持成可沿著前述 壓缸及活塞桿的徑方向移動；在該壓缸裝置，於前述壓缸 的內周側設有「沿著該壓缸的軸方向延伸，且用來導引前 述凸輪構件」的導引套筒，並在該導引套筒形成有前述內 周離合溝，且在前述導引套筒與前述壓缸之間嵌設有彈性 構件。 [發明的效果] 根據本發明，可對應於從該壓缸突出的長度，對活塞 桿作用彈力，此時，可藉由彈性構件，來減輕因離合器手 段的作動所衍生之噪音的產生。 【實施方式】 以下，根據圖面詳細地說明本發明的一個實施形態。 本實施形態的壓缸裝置由第1圖所示，其重要部分的放大 則由第2圖所示。如第1圖及第2圖所示，壓缸裝置1是對活 塞桿2作用反斥力（反作用力），也就是所謂的彈簧緩衝 器’在構成壓缸之略有底的筒狀壓缸構件3的開口端部， 插入有「內周部形成與活塞桿2滑動之軸承」的活塞桿導 具4，活塞桿導具4，是將壓缸構件3的開口端部予以斂縫 201139828 (縮徑）後固定。在活塞桿導具4的內側安裝有油封5，該 油封5爲橡膠製且在內部埋入有金屬環，是用來將壓缸構 件3的內部與外部之間予以密封。 此外，在壓缸構件3之中間部的內部安裝有作爲隔壁 構件的中間導具6，藉由該中間導具6將壓缸構件3的內部 劃分爲：底部側的壓缸部7、與開口部側的活塞桿導引部8 。在該中間導具6，用來連通壓缸部7與活塞桿導引部8的 通路6A是貫穿於軸方向。中間導具6是嵌合於壓缸構件3內 ，且藉由使壓缸構件3的側壁朝內側斂縫（縮徑）而被固 定。而該中間導具6，雖然亦可與活塞桿導具4相同，形成 與活塞桿2滑動的軸承，但在該場合中，由於必須提高活 塞桿導具2與中間導具6之間的同心度，故就製造性而言， 使中間導具6的內徑大於活塞桿導具4的方式較佳。非固定 的活塞（free piston) 9是可滑動地嵌合於壓缸部7，且由 非固定的活塞9，將壓缸部7內劃分成：底部側的氣體室1 〇 、與中間導具6側的壓缸室1 1。 活塞桿2是可滑動且液密地貫穿活塞桿導具4與油封5 ，而插入壓缸構件3。活塞桿2的基端側，是貫穿中間導具 6並延伸至壓缸室11的內部爲止，在該前端部連結著活塞 12。活塞12是可滑動地嵌合於壓缸部7，在其外周安裝有〇 型環13，而將壓缸室11內劃分成下述的2個室：中間導具6 側的活塞桿側室1 1 A、及非固定的活塞9側的底側室1 1 B。 接著，在壓缸室1〗及活塞桿導引部8內，封入作動液，並 在氣體室10內封入大氣壓程度的低壓氣體。該所謂大氣壓 -8 - 201139828 程度的氣體是指：當第1圖所示的活塞桿2於最大伸長時， 使大氣導入氣體室1〇的氣體。藉此，當使用時，由於溫度 條件等，有時較大氣壓更高。 此外，雖然根據壓缸裝置1的要求特性，氣體壓稍微 高一點也無妨，但倘若氣體壓較高時，由於將後述的自由 區間產生若千的彈力，因此最好是形成「較壓缸裝置1或 門等安裝側之摩擦更小的力」的氣體壓。或者，亦可使氣 體室1 0形成大氣開放狀態。在該場合中，最好是朝大氣開 放的孔，設置用來防止異物侵入的過濾器。 在活塞1 2，將活塞桿側室1 1 A與底側室1 1 B予以連通的 連通路14是沿著軸方向貫穿，在連通路14設有衰減力產生 機構15。衰減力產生機構15是由「被安裝於活塞12之活塞 桿側室1 1 A側的端面，且用來開閉連通路1 4」的碟盤狀閥 體所形成，其中央部是在活塞桿2的斂縫（縮徑）部2a之 間’可滑動地（1 . 5 m m左右）嵌插於軸方向。藉此，可作 爲「通常是封閉連通路1 4，僅容許從底側室1 1 B朝活塞桿 側室1 1 A之作動液的流通」的單向閥而發揮作用。此外， 在哀減力產生機構15設有孔口 （orifice)，該孔口 （ orifice)使由「使底側室11 B與活塞桿側室11A常保連通」 的小孔、缺口等所形成。 在活塞桿導引部8設有：用來對活塞桿2作用彈力的彈 簧機構16。以下，針對彈簧機構16的構造進行說明。將圓 筒狀的導引套筒17插入壓缸構件3的活塞桿導引部8內，使 其兩端部抵接於油封5及中間導具6而被固定於軸方向上。 201139828 在導引套筒17的中間部形成有內周溝，也就是指內周離合 溝18。導引套筒17’考慮到內周離合溝18的加工性，在內 周離合溝18之中間導具6側的端部，於軸方向上分割成2個 部份，而由第1導引套筒17A及第2導引套筒17B的2個部份 所形成，在油封5側的第〗導引套筒17A形成有：成爲內周 離合溝18的凹部。導引套筒17，雖然基於強度上的考量， 最好爲金屬製’但爲了輕量化，亦可採用經強化的合成樹 脂。 第1及第2導引套筒17A、17B，其外徑略小於壓缸構件 3之活塞桿導引部8的內徑，且在第1及第2導引套筒17A、 17B之各自的兩端部附近形成有外周溝19、20，在外周溝 19、20則分別嵌合有Ο型環Η、22。如此一來，第1及第2 導引套筒17A、17B，在與活塞桿導引部8之間具有些微的 間隙，且隔著〇型環2 1、2 2而被彈性地支承。 在活塞桿2’面向導引套筒17且在中間部形成有外周 溝，也就是指外周離合溝2 3。內周離合溝1 8與外周離合溝 23 ’其深度大致相等’此外，上述的軸方向端部形成錐狀 〇 在導引套筒1 7與活塞桿2之間，圓筒狀的離合器構件 24是可滑動地沿著軸方向被導引。在離合器構件24的側壁 貫穿有複數個「以放射狀被等間隔配置」的球孔25。在各 個球孔25，成爲凸輪構件的轉動體，也就是指球體26(鋼 球）是可移動地沿著球孔25的軸方向（離合器構件24的徑 方向）插入。球體26的直徑，與球孔25的直徑大致相等， -10- 201139828 此外，形成大致等於「離合器構件24的材料厚度、與內周 離合溝18之深度（與外周離合溝18的深度相等）的總合」 。藉此，球體26在「離合器構件24被插入導引套筒17與活 塞桿2之間」的狀態下’ 一定會形成：卡合於活塞桿2之外 周離合溝23的狀態（請參考第1圖） '或者卡合於導引套 筒1 7之內周離合溝1 8的狀態（請參考第2圖）。由作爲球 體26之保持構件的離合器構件24、與球體26構成：卡脫於 活塞桿2的離合器手段。 在中間導具6與離合器構件24之間，嵌設有作爲彈簧 手段的線圈彈簧2 7 (壓縮彈簧），並藉由其彈力而將離合 器構件24持續朝向油封5側彈推。在離合器構件24的其中 一端部，圓筒狀的彈簧承接部28是一體地形成於同心上， 線圈彈簧27的其中一端部嵌合於彈簧承接部28的外周，且 結合於離合器構件24。此外，在中間導具6的其中一端部 ，圓筒狀的彈簧承接部29—體地形成於同心上，線圏彈簧 的另一端部嵌合於彈簧承接部29的外周，且結合於中間導 具6。藉由利用上述的彈簧承接部28、29來定位線圈彈簧 27的兩端部，可使線圈彈簧27順利地伸縮。此外，離合器 構件24及中間導具6之彈簧承接部28、29的前端部是形成 錐狀，當線圈彈簧27伸縮時，構成線圈彈簧27的線材是設 成不會干涉彈簧承接部2 8、2 9。藉此，既可確實地將線圈 彈簧27予以定位，又可防止因線材的干涉所導致之異音的 產生。 在壓缸構件3的底部及活塞桿2之突出側的前端部，分 -11 - 201139828 別安裝有用來鏈接結合壓缸裝置1的安裝部30、31，上述 安裝部3 0 ' 3 1的形狀，可以設成配合門等被安裝構件的形 狀。 接著，針對如上述所構成之本實施形態的作用進行說 明。第7圖，是從俯視角度觀看「安裝有壓缸裝置1的鉸鏈 門60」之其中一例的說明圖。如第7圖所示，鉸鏈門60， 是藉由鉸鏈62而可開閉地將門板63安裝於門框6 1的門，第 7圖中的圖號（A)是表示門板63的關閉位置，圖號（C) 是表示從關閉位置（A)起開啓大約90°的全開位置，圖號 (B )則表示關閉位置（A )與全開位置（C )的中間位置 (從關閉位置（A )起開啓大約45°的位置）。 壓缸裝置1可作爲輔助門板63之開閉的門開關裝置使 用，該門開閉裝置是將壓缸構件3側的安裝部3 0可轉動地 銷結合於「被固定於門框6 1側」的托架64，且活塞桿2側 的安裝部3 1可轉動地銷結合於「被固定於門板63側」的托 架65，而安裝於鉸鏈門60。此時，活塞桿2在門板63位於 關閉位置（A)或全開位置（C )時，伸長長度變得最大， 當門板6 3位於中間位置（B )時，伸長長度則變得最小， 在該位置’鉸鏈門60的鉸鏈62是位於壓缸裝置1之軸線的 延長線上。 參考第7圖’在門板63位於「從中間位置（B )起之開 閉方向的特定範圍內」的場合中，活塞桿2從壓缸構件3突 出的長度，是位於從最小位置起的特定範圍位。此時，如 第2圖所示’活塞桿2的外周離合溝23是相對於導引套筒17 201139828 的內周離合溝1 8而位於中間導具6側。在該狀態下’被插 入離合器構件24之球孔25的球體26，是卡合於導引套筒17 的內周離合溝1 8，且抵接於活塞桿2的外周面而限制朝徑 方向內側的移動，進而相對於導引套筒1 7將離合器構件24 固定於軸方向，並容許活塞桿2之軸方向的移動。如此一 來，線圈彈簧27的彈力變成由「藉由球體26，相對於導引 套筒17而被固定軸方向上」的離合器構件2 4所支承，不會 對活塞桿2作用。該範圍被稱爲自由區間。 另外，藉由活塞1 2相對於「活塞桿2的伸縮」所產生 的移動，而使壓缸室1 1內的作動液流通至連通路1 4，而由 衰減力產生機構15作用衰減力。此時，在活塞桿2的伸長 行程時，相對於「作動液從連通路14的桿側室1 1 A側朝底 側室1 1 B側的流動」，衰減力產生機構1 5發揮作爲孔口的 功能，而產生特定的衰減力。此外，在縮回行程時，衰減 力產生機構1 5容許「作動液從連通路1 4的底側室1 1 B側朝 活塞桿側室1 1 A側的流動」，而使衰減力變小。 在前述的自由區間，線圈彈簧2 7的彈力不會對「活塞 桿2的伸縮」作用，主要僅作用「藉由活塞12的移動所產 生的衰減力」。此外，雖然藉由壓缸室11內的容積變化而 對氣體室10內的氣體產生壓縮、膨脹，但由於氣體室10內 爲大氣壓程度的低壓，因此該壓力幾乎不會對活塞桿2的 伸縮造成影響。如此一來，由於可在自由區間內，幾乎不 會產生抵抗地使活塞桿2自由伸縮，因此可使門板63自由 地朝開閉兩個方向移動。 -13- 201139828 —旦門板6 3越過自由區間而移動至關閉位置（A )或 全開位置（C)附近爲止時，便如第1圖所示’活塞桿2將 伸長，其外周離合溝23將越過導引套筒17的內周離合溝18 而朝油封5側移動。此時，活塞桿2從壓缸構件3突出的長 度達到特定長度，當活塞桿2的外周離合溝23通過導引套 筒17的內周離合溝18時，「卡合於內周離合溝18，而將離 合器構件24固定於導引套筒17」的球體26將卡合於活塞桿 2的外周離合溝23，離合器構件24將解除對導引套筒17之 軸方向的固定，並相對於活塞桿2而固定於軸方向上。藉 此，線圈彈簧27的彈力將透過離合器構件24而作用於活塞 桿2，而將活塞桿2朝伸長方向彈推。如此一來，門板63在 位於關閉位置（A )附近的場合中，將自動地移動至關閉 位置（A )爲止，此外在位於全開位置（C )附近的場合中 ，則自動地移動至全開位置（C )爲止後形成保持。這樣 的區間被稱爲彈推區間。 在該彈推區間，由於衰減力產生機構1 5相對於活塞桿 2的伸長而如先前所述地發揮孔口的功能，產生特定的衰 減力，故能適度地使門板63的移動速度減速，可減輕門板 63於開閉時的衝撃及噪音。 當活塞桿2從壓缸構件3突出的長度形成特定長度而切 換上述的自由區間與彈推區間時，因爲球體26卡合於導引 套筒17的內周離合溝18或活塞桿23的外周離合溝23，而產 生若干的敲擊聲。相對於該現象，由於導引套筒17A、17B 是由0型環2 1、22所彈性地支承，而不會直接接觸於壓缸 -14 - 201139828 構件3，故能降低傳達至壓缸構件3的敲擊聲，並抑制噪音 的產生。 而在上述的實施形態中’只要是可藉由卡合於內周離 合溝1 8及外周離合溝2 3，而將離合器構件2 4選擇性地固定 於導引套筒17或活塞桿2 ’也可以採用滾子等其他的轉動 體、或者「不會轉動地形成滑動」的凸輪構件，來取代球 體26 〇 接下來，參考第3〜6圖說明上述實施形態的第u變形 例。而在以下的說明中，相對於第1圖及第2圖所示的實施 形態，對相同的部分標示相同的圖號，且僅針對不同的部 分作詳細的說明。 在第3圖及第6圖所示的第1變形例中，是設置具有彈 性之合成樹脂的導引套筒1 7C，來取代被分割成2個部分的 第1及第2導引套筒17A、1 7B中，位於球體26不會轉動之位 置的第2導引套筒17B。在導引套筒17C，並未設置外周溝 20及Ο型環22，而是如第6圖所示，在其外周部一體地形成 複數個「沿著軸方向延伸」的突出部，也就是指凸肋32, 凸肋32的前端部是嵌合於壓缸構件3的活塞桿導引部8內。 凸肋32是沿著周方向，而以相等的間隔所配置。 藉由凸肋32，可減少導引套筒17C與壓缸構件3之間的 接觸面積，此外，藉由凸肋3 2的可撓性、及充滿凸肋32間 之間隙的作動液的振動衰減作用，可降低從導引套筒1 7C 傳達至壓缸構件3的振動、噪音。如此一來，與上述實施 形態相同，可減少傳達至壓缸構件3之「由球體26所引起 -15- 201139828 的敲擊聲」，而抑制噪音的產生。雖然藉由在導引套筒 1 7C的外周形成凸肋3 2，可更進一步達到噪音的降低，但 即使未形成凸肋3 2，也能藉由以合成樹脂形成導引套筒 17C，而產生噪音減少的效果。 在第4圖所示的第2變形例中，導引套筒17是形成一體 ，外周溝19、20及Ο型環21、22僅被設在其兩端部。藉此 ，藉由0型環21、22彈性地支承導引套筒17，與壓缸構件3 之間可形成間隙，而與上述實施形態相同，可減少傳達至 壓缸構件3之「由球體2 6所引起的敲擊聲」，而抑制噪音 的產生。然而，雖然在該場合中可減少零件數量，但由於 內周離合溝1 8成爲圓筒構件之中間部的內周溝，因此被認 爲加工性稍爲困難。 在第5圖所示的第3實施形態中，是將被分割成2個部 份中的第2導引套筒17B予以省略，並將剩餘的另一個第1 導引套筒17A的其中一端部，抵接於「使壓缸構件3之活塞 桿導引部8的側壁，朝內側斂縫（縮徑）」的斂縫部3 3， 而固定於軸方向上。此外，中間導具6，省略了圓筒狀的 彈簧承接部29，藉由「形成於可供活塞桿2插通之開口周 圍」的錐狀凹部，也就是指彈簧承接部34，對線圈彈簧27 的其中一端部施以定位，藉由該錐狀，防止與線圈彈簧27 的線材之間的干涉。如此一來，既能減少零件的數量，又 能達成與上述實施形態相同的作用效果。 然而’雖然在上述的實施形態、及其第1〜3變形例中 ’是藉由縮小作動液所流動的流路面積來獲得衰減力，但 -16- 201139828 也亦可如所謂的摩擦緩衝器般，藉由活塞與壓缸之間的摩 擦而獲得衰減力，只要是能產生衰減力的構造的話，也可 以是其他的構造。但是，藉由採用油液作爲作動流體，可 獲得最穩定的衰減力。 【圖式簡單說明】 第1圖：爲本發明其中一種實施形態之壓缸裝置的縱 剖面圖。 第2圖：是顯示在第1圖的壓缸裝置中，活塞桿經短縮 而彈簧機構的彈力未作用於活塞桿之狀態的重要部分放大 縱剖面圖。 第3圖：是顯示第1圖之壓缸裝置的第1變形例之重要 部分的放大縱剖面圖。 第4圖：是顯示第1圖之壓缸裝置的第2變形例之重要 部分的放大縱剖面圖。 第5圖：是顯示第1圖之壓缸裝置的第3變形例之重要 部分的放大縱剖面圖。 第6圖：爲第3圖之A-A線的横剖面圖。 第7圖：是顯示從俯視角度觀視「將本發明之一種實 施形態的壓缸裝置安裝於門的狀態」的說明圖。 【主要元件符號說明】 1 :壓缸裝置 2 :活塞桿 -17- 201139828 3 :壓缸構件（壓缸） 12 :活塞 17 :導引套筒 1 6 :彈簧機構 1 8 :內周離合溝 21、22 : Ο型環（彈性構件） 24 :離合器構件（保持構件） 26 :球體（凸輪構件） 2 7 :線圈彈簧（彈簧手段） -18-[Technical Field] The present invention relates to a cylinder device used for a door check or the like for "opening and closing of a door". [Prior Art] The following door shutters have been known to the public: by coupling a cylinder device such as a spring damper to a hinged door, the door is opened and closed to exert an elastic force and a damping force, and the door is automatically rotated. Close, or adjust its closing speed, in addition, keep the door in the open position. Conventionally, a door shutter using a cylinder device such as a spring damper has a device as disclosed in Patent Document 1. The door shutter described in Patent Document 1 is linked and coupled between the door of the hinged door and the door frame by a spring damper that "acts the elastic force of the compression coil spring in the direction in which the piston rod is extended". At the opening of the door, when the door is in the vicinity of the closed position, the force in the closing direction is given, and when the door is in the vicinity of the fully open position, the door is held in the open position. [Problem to be Solved by the Invention] However, the technique described in Patent Document 1 has the following problem: the spring buffer is located to be shrunk to In the case of the shortest intermediate position, 'will result in a strong elastic force. Therefore, even when the door is in the middle of the closed position of the switch -5-201139828, the "acting elastic force (finger spring force)" will be formed, so that there is a problem in the case where the door is to be held in the open-close position. An object of the present invention is to provide a solution for solving the above problems. The present invention provides a cylinder device having a cylinder in which an operating fluid is sealed and a piston is slidable. Embedded in the cylinder; and a piston rod that lives on the piston and extends to the outside of the cylinder: and a spring-spring member is disposed in the cylinder, when the piston rod is from the aforementioned length When the piston rod is not more than a certain length, the elastic force is not applied to the piston rod. The spring mechanism has an outer circumferential clutch groove, the outer circumference of the outer circumference of the piston rod, and an inner circumferential clutch groove. The outer circumference is coupled to the outer circumferential clutch groove and is disposed on an inner circumferential side of the pressure cylinder; and the clutch means is configured to be specific when the piston rod is from the cylinder pressure When the piston rod is engaged with the outer circumferential clutch groove and fixed to the axial direction, and is movable in the axial direction with respect to the front, when the piston rod protrudes from the pressure cylinder to a certain length, The inner circumferential clutch groove is engaged with and fixed to the axial direction with respect to the axial direction of the piston rod; and the spring means is a cylinder member for ejecting the middle of the action. a tampon, the piston rod connecting member, the elastic cylinder protruding elastic force, when it is characterized in that the groove is disposed in the groove and the length of the clutch protruding relative to the cylinder is not the aforementioned cylinder and moves to the clutch -6 - 201139828; the clutch means includes: a plurality of cam members, wherein the plurality of cam members are inserted into the inner circumference in a state of being engaged with at least one of the outer circumferential clutch groove and the inner circumferential clutch groove Between the inner circumferential surface of the clutch groove on the cylinder side and the outer circumferential surface of the piston rod; and a holding member 'the retaining member is for the cam member Keeping along the radial direction of the cylinder and the piston rod; the cylinder device is provided on the inner peripheral side of the cylinder to extend along the axial direction of the cylinder and to guide the cam a guiding sleeve of the member, wherein the inner circumferential clutch groove is formed in the guiding sleeve, and an elastic member is embedded between the guiding sleeve and the pressure cylinder. [Effects of the Invention] According to the present invention, the elastic force can be applied to the piston rod in accordance with the length protruding from the cylinder, and at this time, the generation of noise due to the operation of the clutch hand can be reduced by the elastic member. [Embodiment] Hereinafter, an embodiment of the present invention will be described in detail based on the drawings. The cylinder device of the present embodiment is shown in Fig. 1, and the enlargement of the important portion is shown in Fig. 2. As shown in FIGS. 1 and 2, the cylinder device 1 acts on the piston rod 2 with a repulsive force (reaction force), that is, a so-called spring buffer 'in the cylindrical cylinder member that constitutes a slightly bottomed cylinder of the cylinder. A piston rod guide 4 having a "bearing in which the inner peripheral portion forms a slide with the piston rod 2" is inserted into the open end portion of the piston rod 3, and the piston rod guide 4 is used to crimp the open end portion of the cylinder member 3 to 201139828. After the path) is fixed. An oil seal 5 is attached to the inside of the piston rod guide 4, and the oil seal 5 is made of rubber and has a metal ring embedded therein for sealing between the inside and the outside of the cylinder member 3. Further, an intermediate guide 6 as a partition member is attached to the inside of the intermediate portion of the cylinder member 3, and the inside of the cylinder member 3 is divided by the intermediate guide 6 into a cylinder portion 7 on the bottom side and an opening. Piston rod guide 8 on the side. In the intermediate guide 6, the passage 6A for connecting the cylinder portion 7 and the piston rod guide portion 8 is penetrated in the axial direction. The intermediate guide 6 is fitted into the cylinder member 3, and is fixed by caulking (reducing the diameter) of the side wall of the cylinder member 3. The intermediate guide 6 may be the same as the piston rod guide 4 to form a bearing that slides with the piston rod 2. However, in this case, it is necessary to increase the concentricity between the piston rod guide 2 and the intermediate guide 6. In terms of manufacturability, the inner diameter of the intermediate guide 6 is preferably larger than that of the piston rod guide 4. A free piston 9 is slidably fitted to the cylinder portion 7, and a non-fixed piston 9 divides the inside of the cylinder portion 7 into a gas chamber 1 底部 on the bottom side and an intermediate guide. The cylinder chamber 1 on the 6 side. The piston rod 2 is slidably and liquid-tightly inserted through the piston rod guide 4 and the oil seal 5, and is inserted into the cylinder member 3. The proximal end side of the piston rod 2 extends through the intermediate guide 6 and extends into the interior of the cylinder chamber 11, and the piston 12 is coupled to the distal end portion. The piston 12 is slidably fitted to the cylinder portion 7, and the 〇-shaped ring 13 is attached to the outer circumference thereof, and the inside of the cylinder chamber 11 is divided into two chambers: a piston rod side chamber 1 on the side of the intermediate guide 6 A, and the bottom side chamber 1 1 B on the non-fixed piston 9 side. Next, in the cylinder chamber 1 and the piston rod guide portion 8, the operating fluid is sealed, and a low-pressure gas of atmospheric pressure is sealed in the gas chamber 10. The gas of the atmospheric pressure -8 - 201139828 refers to a gas that introduces the atmosphere into the gas chamber 1 when the piston rod 2 shown in Fig. 1 is at the maximum elongation. Thereby, when used, the atmospheric pressure is sometimes higher due to temperature conditions and the like. Further, although the gas pressure is slightly higher depending on the required characteristics of the cylinder device 1, if the gas pressure is high, it is preferable to form a "compressing cylinder device" because the free interval described later generates thousands of elastic forces. 1) The gas pressure of the friction on the mounting side such as the door is smaller. Alternatively, the gas chamber 10 may be made to be in an open atmosphere. In this case, it is preferable that a hole opened to the atmosphere is provided with a filter for preventing entry of foreign matter. In the piston 12, the communication passage 14 that connects the piston rod side chamber 1 1A and the bottom side chamber 1 1 B is penetrated in the axial direction, and the communication passage 14 is provided with a damping force generating mechanism 15. The damping force generating mechanism 15 is formed by a disk-shaped valve body that is attached to the end surface of the piston rod side chamber 1 1 A of the piston 12 and that opens and closes the communication passage 14", and the center portion thereof is at the piston rod 2 The caulking (reduced diameter) portion 2a is slidably inserted (about 1.5 mm) in the axial direction. As a result, it is possible to function as a check valve that normally closes the communication passage 14 and allows only the flow of the fluid from the bottom chamber 1 1 B toward the piston rod side chamber 1 1 A. Further, the sag force generating mechanism 15 is provided with an orifice formed by a small hole, a notch or the like which "maintains the bottom side chamber 11B and the piston rod side chamber 11A". The piston rod guide portion 8 is provided with a spring mechanism 16 for applying an elastic force to the piston rod 2. Hereinafter, the structure of the spring mechanism 16 will be described. The cylindrical guide sleeve 17 is inserted into the piston rod guide portion 8 of the cylinder member 3, and both end portions thereof are brought into contact with the oil seal 5 and the intermediate guide 6 to be fixed in the axial direction. 201139828 An inner circumferential groove is formed in the intermediate portion of the guiding sleeve 17, that is, the inner circumferential clutch groove 18. The guide sleeve 17' takes into consideration the workability of the inner circumferential clutch groove 18, and the end portion of the inner circumferential clutch groove 18 on the side of the intermediate guide 6 is divided into two portions in the axial direction, and is guided by the first guide. The sleeve 17A and the second guide sleeve 17B are formed in two parts, and the first guide sleeve 17A on the oil seal 5 side is formed with a recess that becomes the inner circumference clutch groove 18. The guide sleeve 17 is preferably made of metal based on strength considerations. However, for the purpose of weight reduction, a reinforced synthetic resin may be used. The first and second guiding sleeves 17A and 17B have an outer diameter slightly smaller than the inner diameter of the piston rod guide portion 8 of the cylinder member 3, and are respectively formed by the first and second guiding sleeves 17A and 17B. The outer peripheral grooves 19 and 20 are formed in the vicinity of both end portions, and the meandering rings 19 and 20 are fitted to the outer peripheral grooves 19 and 20, respectively. As a result, the first and second guide sleeves 17A and 17B have a slight gap with the piston rod guide portion 8, and are elastically supported via the 〇-shaped rings 2 1 and 2 2 . The piston rod 2' faces the guide sleeve 17 and is formed with an outer peripheral groove at the intermediate portion, that is, the outer peripheral clutch groove 23. The inner circumferential clutch groove 18 and the outer circumferential clutch groove 23' have substantially the same depth. Further, the axial end portion is formed with a tapered shape between the guide sleeve 17 and the piston rod 2, and the cylindrical clutch member 24 It is slidably guided along the axial direction. A plurality of "holes 25 arranged radially at equal intervals" are inserted through the side wall of the clutch member 24. Each of the ball holes 25 serves as a rotating body of the cam member, that is, the ball 26 (steel ball) is movably inserted in the axial direction of the ball hole 25 (diameter of the clutch member 24). The diameter of the ball 26 is substantially equal to the diameter of the ball hole 25, and -10-201139828 is formed to be substantially equal to the material thickness of the clutch member 24 and the depth of the inner circumferential clutch groove 18 (equal to the depth of the outer circumferential clutch groove 18). total" . Thereby, the ball 26 is surely formed in a state in which the clutch member 24 is inserted between the guide sleeve 17 and the piston rod 2, and is engaged with the clutch groove 23 outside the piston rod 2 (please refer to the first section). Fig.) 'Or the state of the inner circumferential clutch groove 18 of the guide sleeve 17 (refer to Fig. 2). The clutch member 24, which is a holding member of the ball 26, and the ball 26 are constituted by a clutch means that is disengaged from the piston rod 2. Between the intermediate guide 6 and the clutch member 24, a coil spring 27 (compression spring) as a spring means is fitted, and the clutch member 24 is continuously urged toward the oil seal 5 side by its elastic force. At one end portion of the clutch member 24, a cylindrical spring receiving portion 28 is integrally formed concentrically, and one end portion of the coil spring 27 is fitted to the outer circumference of the spring receiving portion 28, and is coupled to the clutch member 24. Further, at one end portion of the intermediate guide 6, a cylindrical spring receiving portion 29 is integrally formed concentrically, and the other end portion of the coil spring is fitted to the outer circumference of the spring receiving portion 29, and is coupled to the intermediate guide. With 6. By positioning the both end portions of the coil spring 27 by the above-described spring receiving portions 28, 29, the coil spring 27 can be smoothly expanded and contracted. Further, the front end portions of the spring receiving portions 28 and 29 of the clutch member 24 and the intermediate guide 6 are tapered, and when the coil spring 27 is expanded and contracted, the wire constituting the coil spring 27 is disposed so as not to interfere with the spring receiving portion 28, 2 9. Thereby, the coil spring 27 can be surely positioned, and the generation of abnormal sound due to the interference of the wire can be prevented. At the bottom of the cylinder member 3 and the front end portion of the protruding side of the piston rod 2, the mounting portions 30, 31 for linking the combined cylinder device 1 are attached to the bottom portion -11 - 201139828, and the shape of the mounting portion 3 0 ' 3 1 is attached. It can be set to match the shape of a member to be mounted such as a door. Next, the operation of the embodiment constructed as described above will be explained. Fig. 7 is an explanatory view showing an example of "the hinged door 60 to which the cylinder device 1 is attached" viewed from a plan view. As shown in Fig. 7, the hinged door 60 is a door that can be opened and closed by the hinge 62 to be attached to the door frame 61, and the figure (A) in Fig. 7 is a closed position of the door panel 63. The number (C) is the fully open position that opens approximately 90° from the closed position (A), and the figure (B) indicates the intermediate position between the closed position (A) and the fully open position (C) (from the closed position (A) Open the position about 45°). The cylinder device 1 can be used as a door opening and closing device for opening and closing the auxiliary door panel 63. The door opening and closing device is configured to rotatably couple the mounting portion 30 on the cylinder member 3 side to the "fixed to the side of the door frame 61". The bracket 64 is attached to the hinged door 60 by the detachably attaching portion 3 of the piston rod 2 side to the bracket 65 that is "fixed to the side of the door panel 63". At this time, when the door panel 63 is in the closed position (A) or the fully open position (C), the extension length becomes maximum, and when the door panel 63 is at the intermediate position (B), the elongation length becomes minimum. The hinge 62 of the position 'hinge door 60 is an extension line on the axis of the cylinder device 1. Referring to Fig. 7 'in the case where the door panel 63 is located within a specific range of the opening and closing direction from the intermediate position (B), the length of the piston rod 2 protruding from the cylinder member 3 is a specific range from the minimum position. Bit. At this time, as shown in Fig. 2, the outer circumferential clutch groove 23 of the piston rod 2 is located on the intermediate guide 6 side with respect to the inner circumferential clutch groove 18 of the guide sleeve 17201139828. In this state, the ball 26 inserted into the ball hole 25 of the clutch member 24 is engaged with the inner circumferential clutch groove 18 of the guide sleeve 17, and abuts against the outer peripheral surface of the piston rod 2 to restrict the radial direction. The inner movement further fixes the clutch member 24 in the axial direction with respect to the guide sleeve 17 and allows the movement of the piston rod 2 in the axial direction. As a result, the elastic force of the coil spring 27 is supported by the clutch member 24 which is "fixed in the axial direction by the ball 26 with respect to the guide sleeve 17," and does not act on the piston rod 2. This range is called the free interval. Further, the movement of the piston 12 in the cylinder chamber 1 1 is caused to flow to the communication passage 14 by the movement of the piston 1 2 with respect to the "expansion and contraction of the piston rod 2", and the damping force generating mechanism 15 acts on the damping force. At this time, in the elongation stroke of the piston rod 2, the damping force generating mechanism 15 functions as an orifice with respect to the "flow of the operating fluid from the rod side chamber 1 1 A side of the communication passage 14 toward the bottom side chamber 1 1 B side". Function, which produces a specific damping force. Further, at the time of the retracting stroke, the damping force generating means 15 allows "the flow of the operating fluid from the bottom side chamber 1 1 B side of the communication passage 14 toward the piston rod side chamber 1 1 A side" to reduce the damping force. In the above-described free section, the elastic force of the coil spring 27 does not act on the "expansion and contraction of the piston rod 2", and mainly acts only on the "damping force generated by the movement of the piston 12". Further, although the gas in the gas chamber 10 is compressed and expanded by the volume change in the cylinder chamber 11, since the gas chamber 10 has a low pressure at atmospheric pressure, the pressure hardly contracts the piston rod 2. Make an impact. In this way, since the piston rod 2 can be freely expanded and contracted with little resistance in the free section, the door panel 63 can be freely moved in both the opening and closing directions. -13- 201139828 - When the door panel 6 3 moves past the free section and moves to the vicinity of the closed position (A) or the fully open position (C), the piston rod 2 will expand as shown in Fig. 1, and the outer circumferential clutch groove 23 will The inner circumferential clutch groove 18 of the guide sleeve 17 is moved toward the oil seal 5 side. At this time, the length of the piston rod 2 protruding from the cylinder member 3 reaches a certain length. When the outer circumferential clutch groove 23 of the piston rod 2 passes through the inner circumference clutch groove 18 of the guide sleeve 17, "engages with the inner circumference clutch groove 18". The ball 26 that fixes the clutch member 24 to the guiding sleeve 17" will engage with the outer circumferential clutch groove 23 of the piston rod 2, and the clutch member 24 will release the fixing of the guiding sleeve 17 in the axial direction, and relative to The piston rod 2 is fixed in the axial direction. Thereby, the elastic force of the coil spring 27 acts on the piston rod 2 through the clutch member 24, and the piston rod 2 is pushed in the extending direction. As a result, when the door panel 63 is located near the closed position (A), it will automatically move to the closed position (A), and in the case of the vicinity of the fully open position (C), it will automatically move to the fully open position. (C) forms a hold after that. Such an interval is called a bombing interval. In the pop-up section, since the damping force generating mechanism 15 functions as an orifice as described above with respect to the elongation of the piston rod 2, a specific damping force is generated, so that the moving speed of the door panel 63 can be moderately decelerated. The flushing and noise of the door panel 63 during opening and closing can be reduced. When the length of the piston rod 2 protruding from the cylinder member 3 is formed to a specific length to switch the above-described free section and the elastic section, since the ball 26 is engaged with the outer circumference of the guide sleeve 17 or the outer circumference of the piston rod 23 The clutch groove 23 is generated to generate a number of knocking sounds. With respect to this phenomenon, since the guide sleeves 17A, 17B are elastically supported by the 0-rings 2 1 and 22 and do not directly contact the members 3 of the cylinders 14 - 201139828, the transmission to the cylinder members can be reduced. 3 knocking sounds and suppress noise generation. In the above embodiment, the clutch member 24 is selectively fixed to the guide sleeve 17 or the piston rod 2 as long as it can be engaged with the inner circumference clutch groove 18 and the outer circumference clutch groove 2 3 . Instead of the spherical body 26, another rotator such as a roller or a cam member that "slides without rotating" may be used. Next, the u-th modification of the above embodiment will be described with reference to Figs. In the following description, the same reference numerals are given to the same parts in the first embodiment and the second embodiment, and only the different parts will be described in detail. In the first modification shown in FIGS. 3 and 6, a guide sleeve 1 7C having an elastic synthetic resin is provided instead of the first and second guide sleeves divided into two portions. In the 17A and 17B, the second guide sleeve 17B is located at a position where the ball 26 does not rotate. In the guide sleeve 17C, the outer circumferential groove 20 and the Ο-shaped ring 22 are not provided, but as shown in Fig. 6, a plurality of "extending in the axial direction" are integrally formed on the outer peripheral portion thereof, that is, The finger rib 32 is formed, and the front end portion of the rib 32 is fitted into the piston rod guide portion 8 of the cylinder member 3. The ribs 32 are arranged at equal intervals along the circumferential direction. By the rib 32, the contact area between the guide sleeve 17C and the cylinder member 3 can be reduced, and the flexibility of the rib 32 and the vibration of the operating fluid filled with the gap between the ribs 32 can be reduced. The damping action reduces vibration and noise transmitted from the guide sleeve 1 7C to the cylinder member 3. As a result, in the same manner as in the above embodiment, the "knocking sound of -15 - 201139828 caused by the ball 26" transmitted to the cylinder member 3 can be reduced, and noise generation can be suppressed. Although the noise reduction can be further achieved by forming the rib 3 2 on the outer circumference of the guide sleeve 17C, the guide sleeve 17C can be formed of synthetic resin even if the rib 3 2 is not formed. Produces a noise reduction effect. In the second modification shown in Fig. 4, the guide sleeve 17 is integrally formed, and the outer circumferential grooves 19 and 20 and the Ο-shaped rings 21 and 22 are provided only at both end portions. Thereby, the guide sleeve 17 is elastically supported by the 0-rings 21 and 22, and a gap can be formed between the cylinders 3 and the cylinder member 3, and the spherical body can be reduced to be transmitted to the cylinder member 3 as in the above embodiment. 2 6 caused by the knocking sound, and suppresses the noise. However, although the number of parts can be reduced in this case, since the inner circumferential clutch groove 18 becomes the inner circumferential groove of the intermediate portion of the cylindrical member, it is considered that the workability is slightly difficult. In the third embodiment shown in Fig. 5, the second guide sleeve 17B divided into two portions is omitted, and one end of the remaining other first guide sleeve 17A is omitted. The portion abuts on the caulking portion 3 3 which causes the side wall of the piston rod guide portion 8 of the cylinder member 3 to be caulked (reduced in diameter), and is fixed in the axial direction. Further, the intermediate guide 6 omits the cylindrical spring receiving portion 29, and the "cone-shaped recessed portion formed around the opening through which the piston rod 2 can be inserted", that is, the spring receiving portion 34, the coil spring One end portion of 27 is positioned to prevent interference with the wire of the coil spring 27 by the tapered shape. As a result, the number of parts can be reduced, and the same effects as those of the above embodiment can be achieved. However, in the above-described embodiment and the first to third modifications, the damping force is obtained by reducing the flow path area through which the operating fluid flows, but -16-201139828 may also be a so-called friction buffer. In general, the damping force is obtained by the friction between the piston and the pressure cylinder, and other structures may be used as long as it is a structure capable of generating a damping force. However, by using oil as the actuating fluid, the most stable damping force can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a longitudinal sectional view showing a cylinder device according to an embodiment of the present invention. Fig. 2 is an enlarged longitudinal sectional view showing an important part of the cylinder device of Fig. 1 in which the piston rod is shortened and the spring force of the spring mechanism is not applied to the piston rod. Fig. 3 is an enlarged longitudinal sectional view showing an important part of a first modification of the cylinder device of Fig. 1. Fig. 4 is an enlarged longitudinal sectional view showing an important part of a second modification of the cylinder device of Fig. 1. Fig. 5 is an enlarged longitudinal sectional view showing an important part of a third modification of the cylinder device of Fig. 1. Fig. 6 is a cross-sectional view taken along line A-A of Fig. 3. Fig. 7 is an explanatory view showing a state in which a cylinder device according to an embodiment of the present invention is attached to a door from a plan view. [Main component symbol description] 1 : Cylinder device 2 : Piston rod -17- 201139828 3 : Cylinder member (cylinder) 12 : Piston 17 : Guide sleeve 1 6 : Spring mechanism 1 8 : Inner circumference clutch groove 21 , 22 : Ο type ring (elastic member) 24 : clutch member (holding member) 26 : ball (cam member) 2 7 : coil spring (spring means) -18-