201040393 六、發明說明： 【發明所屬之技術領域】 本發明是用來壓縮流體的螺旋壓縮機，特別是適合作 爲「用於空調機或冷凍機等的冷凍循環」的螺旋壓縮機。 【先前技術】 螺旋壓縮機，是將具有「被彎折成3次元（3維）之 0 構成曲面」的螺旋轉子作爲壓縮機構部。因爲這個緣故， 用來收納壓縮機構部的殼體，一般是採用能成形爲複雜形 狀的鑄鐵。通常被作爲壓縮機的殻體使用的鑄鐵，強度較 壓力配管用鋼材更低。在設計壓力相同的場合中，鑄鐵製 殼體的材料厚度必須較鋼材製殼體更厚，因此具有壓縮機 質量增加的缺點。此外，螺旋壓縮機必須將排放氣體中所 含有的潤滑油予以分離，因此，大多是將油分離器一體化 地製作於壓縮機上，由於油分離器也是鑄鐵製，而具有壓 〇 縮機的質量大幅增加的課題。 另外，也考慮如同迴轉式壓縮機或渦捲式壓縮機般， 將壓縮機構部收納於鋼管製腔室內，使螺旋壓縮機小型輕 量化。舉例來說，如專利文獻1所示，形成將螺旋壓縮機 的壓縮機構部收納於鋼管製腔室內的構造。該種習知技術 的裝置，是採用「鋼管製腔室內的壓力呈高壓」的構造。 此外，就其他的習知例而言’也考慮以下構造的螺旋 壓縮機：將鑄鐵製壓縮機構部收納於鋼管製腔室內，並在 鋼管與鑄鐵的異種金屬間實施銲接，而將鋼管製腔室內分 -5- 201040393 隔成低壓部與高壓部。 〔專利文獻1〕美國專利第4545 742號 【發明內容】 〔發明欲解決之課題〕 藉由在螺旋壓縮機中採用鋼管製腔室，可實現小型輕 量化。但是在習知的螺旋壓縮機卻具有以下所示的課題。 在鋼管製腔室內的壓力形成冷媒氣體壓縮後之高壓的 場合中，是形成以高壓、高溫的冷媒氣體來執行電動機的 冷卻。因爲這個緣故，在壓縮機的運轉中，存有電動機過 熱的危險性，就信賴性的觀點而言是有問題的。相反地， 也可以使鋼管製腔室內的壓力形成冷媒氣體壓縮前的低壓 。但是，在使鋼管製腔室內形成低壓的構造中，「在鋼管 製腔室內設置油分離器」變得困難，而必須將油分離器與 壓縮機獨立設置，而具有壓縮機全體變得大型化的缺點。 此外’在「利用於鋼管與鑄鐵的異種金屬間的銲接而 形成分隔低壓部與高壓部之構造」的場合中，雖然異種金 屬間的銲接是可能的’但倘若未設定最適當的銲接條件， 將因爲銲接部的熔入不足而產生龜裂，而具有：氣體浅漏 或高壓冷媒氣體朝低壓部浅漏，而引發性能下降的課題。 不僅如此，在該構造中，必須銲接鋼管製腔室的全周而分 隔成低壓部與商壓部’而使銲接長度變長。因此，還具有 「在銲接部產生龜裂的潛在性升高」的課題，特別是對大 容量的壓縮機有適用上的困難。此外，―日採用該構造， _ 6 - 201040393 由於形成密閉構造，還具有：無法執行軸承交換等之維修 保養的課題。 如以上所述，在「將螺旋壓縮機的壓縮機構部收納於 鋼管製腔室內」的構造中，由於壓縮機形成半密閉化，是 很難將電動機配置於低壓側、且將油分離器配置於高壓側 。亦即，鋼管製腔室構造對小型輕量化而言是絕佳的構造 ，相反地對維修保養性與信賴性而言卻具有不佳的問題。 0 本發明的目的在於：小型輕量並具有絕佳的維修保養 性，且獲得高信賴性的螺旋壓縮機。 〔解決課題手段〕 爲了達成上述目的，本發明是具備下述構件的螺旋壓 縮機：由齒形部與軸部所構成的螺旋轉子、和支承該螺旋 轉子之軸部的低壓側軸承與高壓側軸承、和直結於前述螺 旋轉子之軸部的驅動用馬達、和收容著該馬達的馬達殼體 Ο 、和收容著前述螺旋轉子與前述低壓側軸承的主殻體、及 收納著前述螺旋轉子之高壓側軸承的排放殼體，其特徵爲 :具備用來收容前述馬達殻體、前述主殼體及前述排放殼 體的鋼管製腔室；前述鋼管製腔室是由可在軸方向上分割 的低壓側腔室與高壓側腔室所構成；由設於前述鋼管製腔 室之內面的凸緣、和設於前述主殼體或馬達殼體的凸緣、 及設於上述凸緣間的密封要件構成··將前述鋼管製腔室內 的空間分隔成低壓部側的空間與高壓部側的空間。 在此，前述低壓側腔室與前述高壓側腔室，也可以形 201040393 成：藉由利用設於上述兩者之外面端部的凸緣而結合的方 式，使鋼管腔室內對外氣形成密封的構造。此外，前述高 壓側腔室更進一步在軸方向上分割成2個部分，而由與前 述低壓側腔室連接的第1高壓側腔室、及連接於該第1高 壓側腔室的第2高壓側腔室所構成，上述的第1、第2高 壓側腔室，最好是形成：藉由設於上述兩者之外面端部的 凸緣所結合，而使鋼管腔室內對外氣形成密封的構造。 此外，前述鋼管製腔室內的空間，可藉由以下的方式 分隔成低壓部側的空間與高壓部側的空間：設於前述高壓 側腔室內面的凸緣、與設在前述主殼體的凸緣隔著密封要 件而連接；設於前述高壓側腔室內面的凸緣、與設於前述 馬達殼體的凸緣隔著密封要件連接；設於前述低壓側腔室 內面的凸緣、與設於前述主殼體的凸緣隔著密封要件而連 接；或者設於前述低壓側腔室內面的凸緣、與設於前述馬 達殼體的凸緣隔著密封要件而連接。 構成前述鋼管製腔室之外殻的中心軸，最好是被配置 於水平方向。 在本發明中，前述螺旋轉子最好是由：相互嚙合的至 少一對公轉子及母轉子所構成。此外，被本發明的螺旋壓 縮機所壓縮的作動流體，是冷凍循環所使用的冷媒，該冷 媒是使用「每個單位體積流量的冷卻能力爲冷媒R407C之 7 0%以下」的冷媒，只要將前述螺旋轉子的公轉子齒數設 成4齒，將母轉子齒數設成6齒，並利用變流器來驅動直 結於前述公轉子的驅動用馬達，便能使用地球暖化係數低 -8- 201040393 的冷媒（低GWP冷媒）。 此外，最好是構成：將前述鋼管製腔室的中心軸配置 在前述公轉子的中心軸與前述母轉子的中心軸之間。 而前述螺旋壓縮機，同樣可適用於具備下述構件者： 與螺旋轉子相互嚙合的柵門轉子、及用來支承該柵門轉子 之軸部的軸承。 針對具備「由齒形部與軸部所構成的螺旋轉子、和與 0 該螺旋轉子嚙合的柵門轉子、和支承前述螺旋轉子之軸部 的低壓側軸承與高壓側軸承、和支承前述栅門轉子之軸部 的軸承、和「直結於前述螺旋轉子之軸部，並驅動該螺旋 轉子」的馬達、和收容著該馬達的馬達殼體、及收容著前 述螺旋轉子與前述柵門轉子的主殼體」的螺旋壓縮機，本 發明的其他特徵在於：具備用來收容前述馬達殼體與前述 主殼體的鋼管製腔室，前述鋼管製腔室是由可在軸方向上 分割的低壓側腔室與高壓側腔室所構成，並藉由設於前述 〇 鋼管製腔室之內面的凸緣'設於前述主殼體或馬達殼體的 凸緣、及設於上述凸緣間的密封要件，而構成將前述鋼管 製腔室內的空間分隔成低壓部側的空間與高壓部側的空間 〇 針對具備「螺旋轉子、和支承該螺旋轉子的軸承、和 驅動前述螺旋轉子的馬達、和收容著該馬達的馬達殻體、 及收容著前述螺旋轉子的主殼體」的螺旋壓縮機，本發明 的另一個其他的特徵在於：具備用來收容前述馬達殼體與 前述主殼體的鋼管製腔室’該鋼管製腔室是構成可在軸方 -9 - 201040393 向上分割’且前述可分割的鋼管製腔室內的空間，是隔著 密封要件而分隔成低壓部側的空間與高壓部側的空間。 〔發明效果〕 根據本發明’由於具備用來收容馬達殻體與主殼體的 鋼管製腔室，該鋼管製腔室構成可在軸方向上分割，且該 可分割之鋼管製腔室內的空間，是形成「可隔著密封要件 而分隔成低壓部側的空間與高壓部側的空間」的構造，因 此能獲得：小型輕量並具有絕佳維修保養性，且高信賴性 的螺旋壓縮機。 【實施方式】 以下，根據圖面來說明本發明中具體的實施例。在各 圖中，標示相同圖號的部分，是指相同或者相當的部分。 〔實施例1〕 第1圖中顯示本發明的實施例1。雖然在以下的說明 中，是採用「具有公、母兩個螺旋轉子的雙軸型螺旋壓縮 機」來作爲實施例說明，但本發明並不侷限於雙軸型螺旋 壓縮機，單一螺旋轉子的單軸型螺旋壓縮機也同樣能適用 0 如第1圖所示，螺旋壓縮機具有相互連接的馬達殼體 1、主殼體2、及排放殼體3。馬達殼體1收納著「用來驅 動壓縮機構部」的驅動用馬達4，並利用螺栓等手段而固 -10- 201040393 定於主殼體2。在主殻體2形成有：圓筒狀鏜孔5、及用 來將冷媒氣體導入圓筒狀鏜孔5的吸入埠6。在圓筒狀鏜 孑L 5內，由滾子軸承7、8、9 ( 7、8爲低壓側軸承，9爲 高壓側軸承）及滾珠軸承1 2 (高壓側軸承）支承成可轉動 的公轉子14、及母轉子（圖面中未顯示）是相互嚙合地被 收納’公轉子1 4的軸是直結於馬達4。在排放殻體3收納 有滾子軸承9及滾珠軸承12(高壓側軸承），這些軸承是 0 利用螺栓等手段而固定於主殻體2。此外，在排放殼體3 的其中一端，安裝著用來封閉「收納滾子軸承9、及滾珠 軸承12之軸承室16」的遮蔽板17。 在主殻體2及排放殼體3內形成有供油通路1 8、1 9， 而構成連通「設於高壓側腔室22、23下部」的油池20、 及前述各軸承部。 馬達殼體1、主殼體2'及排放殼體3，是被收納於「 構成可在軸方向上分割」的鋼管製腔室內。鋼管製腔室是 ❹ 由低壓側腔室2 1 ;及高壓側腔室2 2、2 3所構成，形成於 各腔室外面端部的凸緣24、25、26、27，是藉由密封要件 (圖面中未顯示）並利用螺栓等手段所連接，而使鋼管製 腔室內對外氣形成密封，且形成可在軸方向上分割的構造 。前述高壓側腔室在軸方向上被分割成2個部份，而由與 前述低壓側腔室連接的第1高壓側腔室22、及連接於該第 1高壓側腔室22的第2高壓側腔室23所構成。 形成於主殼體2的凸緣29、與形成於高壓側腔室22 內部的凸緣28，是隔著密封要件30而由螺栓等所連接。 -11 - 201040393 如此一來，鋼管腔室內的空間31、32被分隔成：空間31 成爲低壓側空間，空間3 2成爲高壓側空間。 接著，說明冷媒氣體及油的流動。 從設於低壓側腔室2 1之吸入口 3 3所吸入的低溫、低 壓冷媒氣體，是經濾篩34捕集異物後，通過「被設於馬 達4與馬達殼體1之間」的氣體通路、及「馬達的定子4a 與轉子4 b間」的氣隙（a i r - g a p )，而冷卻馬達4。經冷 卻後的冷媒氣體，是從形成於主殼體2的吸入埠6，而被 吸入由「因公、母螺旋轉子而嚙合」的齒面與主殼體2所 形成的吸入室，在此之後，隨著連接於馬達4之公轉子14 的轉動，而被密封於「由公、母螺旋轉子的嚙合齒面、與 主殼體2所形成」的壓縮室，並由於简JS縮室的縮小而緩 緩地被壓縮並成爲高溫、高壓的冷媒氣體。該經壓縮的冷 媒氣體，是通過由排放殼體3所構成的排放通路3 5及排 放配管36，而朝構成高壓側腔室23的鏡板37排放。 在壓縮時作用於公、母螺旋轉子的壓縮反作用力之中 ，徑向負載是由滾子軸承7、8、9所支承，而推力負載則 由滾珠軸承1 2所支承。上述軸承的潤滑及冷卻用油，是 從設於高壓側腔室22、23之下部的油池20，通過「連通 於各軸承部」的供油通路1 8、1 9，並利用差壓而供油。經 供油後的油，是與壓縮冷媒氣體一起朝構成高壓側腔室23 的鏡板3 7排放。壓縮冷媒氣體所含有的油’是在藉由衝 撞鏡板3 7而產生的一次分離後，由「被設置於高壓側腔 室23的除霧器38等」的捕集式油分離器形成二次分離’ -12- 201040393 而貯留於「設置於高壓側腔室22、23之下部」的油 。壓縮冷媒氣體’是通過_壓側腔室22之上部的氣 路3 9，並由「被設於高壓側腔室22」的排放口 40所 〇 在習知的螺旋壓縮機中’馬達殻體丨、主殼體2 放殼體3是藉由相互地連接所密封’具有「保持內部 之耐壓殼體」的功能。另外’螺旋壓縮機’爲了收納 0 有被彎折成3次元（3維）的複雜構成曲面」的螺旋 、和容量控制用滑閥（slide valve)，而形成複雜的 構造。因此，螺旋壓縮機的殻體一般是採用「可成形 雜形狀」的鑄鐵。在採用鑄鐵作爲殼體的場合中’由 度較壓力配管用的鋼材更低’爲了維持而不得不增加 的材料厚度，而具有使壓縮機之質量增加的傾向。相 上述的情形，在本實施例的構造中，由於是以鋼管製 來保持內部壓力，故鑄鐵製的主殼體2是以收納壓縮 Q 部作爲其主要目的。因此，能將鑄鐵製殼體的質量抑 最小的限度，可獲得小型輕量的螺旋壓縮機。 而在第1圖的實施例中，是將構成鋼管製腔室之 的中心軸，配置於水平方向上。在將鋼管製腔室配置 平方向的場合中，由於形成低重心，當搬出、搬入壓 時具有良好的穩定性。但是，本發明並不侷限於將鋼 腔室配置於水平方向，即使將「構成鋼管製腔室之外 的中心軸配置於垂直方向，也能將「用來收納壓縮機 」之纟專鐵製威體的質量抑制成最小限度。 I 20 體通 排放 及排 壓力 「具 轉子 殼體 爲複 於強 殼體 對於 腔室 機構 制成 外殼 於水 縮機 管製 殼」 構部 -13- 201040393 將鑄鐵製殼體收納於鋼管製腔室內的習知螺旋壓縮機 ，是形成：鋼管製腔室內的壓力’是由冷媒氣體壓縮前的 低壓、或者冷媒氣體壓縮後的高壓之其中任一種所構成的 構造；或者藉由在鋼管與鑄鐵的異種金屬間銲接’而分隔 成高壓室與低壓室的。 在鋼管製腔室內爲低壓的場合中’由於必須將經螺旋 轉子壓縮的冷媒氣體直接排放至鋼管製腔室外部’故難以 將油分離器設置於鋼管製腔室內。因此’必須另外設置油 分離器，而難以小型化。 在鋼管製腔室內爲高壓的場合中，是形成以高壓、高 溫的冷媒氣體來實施驅動用馬達4的冷卻’由於在壓縮機 的運轉中導致驅動用馬達4過熱，而具有信賴性的問題。 此外，雖然驅動用馬達4的絶緣材是由樹脂材料所構成’ 但這些樹脂材料的耐熱等級也必須提升。 在藉由異種金屬間的銲接而形成「分隔成高壓室與低 壓室」之構造的場合中，一旦銲接條件的設定不當（意指 非最合適者），將在異種金屬間的銲接部產生因熔入不足 所引起的龜裂，致使高壓的冷媒氣體洩漏至低壓部而導致 性能下降。此外，爲了分隔成高壓室與低壓室，鋼管製腔 室有必要全周銲接，而越是大容量的壓縮機，其銲接長度 而越長，而提高了高壓冷媒氣體洩漏至低壓部的危險性。 因此，這種構造不適用於大容量的壓縮機。 相對於上述的狀況，藉由形成本實施例的構造，由於 鋼管製腔室內是形成「隔者密封要件30而分隔成局低壓 -14- 201040393 」的構造，故可以將驅動用馬達4配置於鋼管製腔室內的 低壓側，將油分離器配置於鋼管製腔室內的高壓側。藉由 構成上述的說明’可以兼顧：由低壓、低溫的冷媒氣體對 馬達4的冷卻、及油分離器朝鋼管製腔室內的配置。 在本實施例中，油分離器是形成倂用「利用鏡板3 7 的衝突式油分離」與「利用除霧器38的捕集式油分離」 的構造。此外，由於形成「以密封要件3 0分隔低壓部與 0 高壓部」的構造，故具有良好的氣密性，且「高壓冷媒氣 體洩漏至低壓部而使性能下降」的危險性極低。不僅如此 ，由於鋼管製腔室可分割成低壓側腔室2 1 ;與高壓側腔室 22、23，因此軸承更換等的維修保養也變得能輕易地執行 〔實施例2〕 第2圖中顯示本發明的實施例2。與第1圖的實施例 Q 相同，鋼管製腔室是由低壓側腔室2 1及高壓側腔室22、 23所構成，藉由利用螺栓等的手段連接「形成於各腔室的 凸緣24、25、26、27」，使低壓側腔室2 1與高壓側腔室 22、23互相構成密封關係’且形成：既能對外氣形成密封 構造，又能分割的構造。 在本實施例中，形成於馬達殼體1的凸緣29、與形成 於高壓側腔室22內部的凸緣28，是隔著密封要件30而由 螺栓等所連接的這點是不同於實施例1。在本實施例中， 鋼管製腔室內的空間31、3 2是被分隔成：空間3 1成爲低 -15- 201040393 壓側空間，而空間32成爲高壓側空間’而能兼顧··低壓 、低溫的冷媒氣體對驅動用馬達4的冷卻；及油分離器朝 鋼管製腔室內的配置，進而成爲：低壓部與高壓部的氣密 性良好，且維修保養也容易的構造。 〔實施例3〕 第3圖中顯示本發明的實施例3。與第1圖的實施例 相同，鋼管製腔室是由低壓側腔室2 1與高壓側腔室22所 構成，由螺栓等手段將形成於各腔室的凸緣24、25連接 成密封關係，並構成可分割的構造。在本實施例中，形成 於主殼體2的凸緣29與形成於低壓側腔室21內部的凸緣 28，是隔著密封要件3 0而由螺栓等所連接，鋼管製腔室 內的空間3 1、3 2則被分隔成：空間3 1成爲低壓側空間， 空間3 2成爲高壓側空間。在本實施例中，可兼顧：低壓 、低溫的冷媒氣體對驅動用馬達4的冷卻；及油分離器朝 鋼管製腔室內的配置，而成爲：低壓部與高壓部的氣密性 良好，且維修保養也容易的構造。 在本實施例中，由於「即使不分割高壓側腔室2 2，壓 縮機也能分解組裝」，因此相較於必須分割高壓側腔室22 的實施例’則不需要連接於高壓腔室間的凸緣和密封要件 ’具有可獲得「簡單且信賴性更高之壓縮機」的效果。 〔實施例4〕 第4圖中顯示本發明的實施例4。與第1圖的實施例 -16- 201040393 相同，鋼管製腔室是由低壓側腔室2 1與高壓側腔室22 構成，藉由以螺栓等手段將形成於各腔室的凸緣24、 連接成密封關係，而構成可分割的構造。在本實施例中 「形成於馬達殻體1的凸緣29與形成於低壓側腔室2 1 部的凸緣28，是隔著密封要件30而由螺栓等所連接」 這點是與上述各實施例不同。在本實施例中，鋼管製腔 內的空間3 1、3 2也被分隔成：空間3 1成爲低壓側空間 Λ 空間3 2成爲高壓側空間。藉此，可兼顧：低壓、低溫 Ο 媒氣體對驅動用馬達4的冷卻；及油分離器朝鋼管製腔 內的配置，而形成：低壓部與高壓部的氣密性良好，且 容易地維修保養的構造。此外，在本實施例中也與實施 3相同，由於「即使不分割高壓側腔室22，壓縮機也能 解組裝」，因此不需要「當高壓側腔室22經分隔時成 必需品」之高壓腔室間的密封要件。 〔實施例5〕 第5圖中顯示本發明的實施例5。與第1圖的實施 相同，鋼管製腔室是由低壓側腔室2 1與高壓側腔室22 23所構成，藉由以螺栓等手段將形成於各腔室的凸緣 、25、26、27連接成密封關係，而形成可分割的構造。 本實施例中’與外殻41構成一體的凸緣25 ’是配置成 越外殼4 1之外氣側25 a與冷媒側2 5 b的兩側。在本實 例中，由於外殻41內部無須另外設置與殼體連接用的 緣，故能以更簡單的構造，將鋼管製腔室內分隔成低壓 所 25 5 內 的 室 冷 室 能 例 分 爲 例 2 4 在 跨 施 凸 側 -17- 201040393 空間31與高壓側空間32。 雖然在本實施例中，是形成以螺栓等連接「形成於主 殻體2的凸緣29」與「形成於高壓側腔室22的凸緣25」 的構造，但即使是構成以下的構造也能獲得相同的效果： 以螺栓等連接「形成於馬達殼體的凸緣、與形成於高壓側 腔室的凸緣」，·或「形成於主殼體的凸緣、與形成於低壓 側腔室的凸緣」；或者「形成於馬達殼體的凸緣、與形成 於低壓側腔室的凸緣」。 〔實施例6〕 第6圖中顯示本發明的實施例6。與第1圖的實施例 相同，馬達殼體1、主殻體2、排放殼體3是被收納於「 構成可分割的鋼管製腔室內」。本實施例是採用「每個單 位體積流量的冷卻能力，爲冷媒R4 0 7 C之7 0 %以下」的冷 媒，作爲經壓縮之作動冷媒的範例。在本實施例中，收容 於主殼體2的螺旋轉子是由以下的條件所構成：公轉子i 4 的齒數爲4齒’母轉子I5的齒數爲6齒；並以變流器43 來驅動「直結於公轉子1 4之軸部」的驅動用馬達4。 就空調機或冷凍機所使用的冷媒而言，存在有R4 1 〇A 、R407C、R134a、氨、二氧化碳等數量繁多的種類，且 每一種的「每個單位體積流體之冷卻能力」也不同。在假 設空調機或冷凍機所要求的冷卻能力爲相同的場合中，由 於倘若採用每個單位體積之冷卻能力大的冷媒，將使壓縮 機的理論排放量變小，故可使壓縮機小型化。相反地，在 -18- 201040393 採用每個單位體積之冷卻能力小的冷媒的場合中，壓縮機 將變的大型化。舉例來說，在將冷媒R407C之每個單位體 積流量的冷卻能力設成100的場合中，R410A約成爲15〇 ，而Rl 3 4a約成爲65。因爲這個緣故，在欲獲得相同冷 卻能力的場合中，相較於R407C或R410A ’倘若採用 R1 34a作爲冷媒，將使壓縮機變的大型化。雖然最近廣受 注目之地球暖化係數低的冷媒（低GWP冷媒），大多數 0 是譬如與R 1 3 4a相同，爲每個單位體積流量之冷卻能力小 的冷媒，但只需根據本實施例，即使採用上述的低GWP 冷媒，也能實現壓縮機的輕量化。 雖然螺旋壓縮機的公轉子14與母轉子15的齒數，存 在有分別爲5齒與6齒、以及5齒與7齒等的組合，但在 轉子徑相同的場合中，由於齒數越少則齒溝的面積越大， 故具有使理論排放量增加的傾向。本實施例形成：即使在 採用每個單位體積流量之冷卻能力小的冷媒的場合中，將 〇 公轉子14與母轉子15的齒數組合分別設定成4齒與6齒 ’並以變流器43驅動直結於公轉子丨4之軸部的驅動用馬 達4 ’而可以增速的構造。根據本實施例，可以對「採用 外部電源44，且以一定速度驅動」的壓縮機，實現大幅的 小型·輕量化。 〔實施例7〕 第7圖中顯示本發明的實施例7。與第！圖的實施例 相同’馬達殻體1、主殻體2、排放殻體3是被收納於「 "19- 201040393 構成可分割的鋼管製腔室內」。本實施例’是構成將鋼管 製腔室的中心軸47，配置於：公轉子14;和直結於該公 轉子1 4之驅動用馬達4的中心軸4 5 ;及母轉子1 5的中心 軸46之間。在雙軸型的螺旋壓縮機中，是必然存在有「 公轉子14的中心軸」與「母轉子15的中心軸」的2個軸 。藉由將鋼管製腔室的中心軸配置於上述2個軸之間，可 以降低「把鑄鐵製殼體配置於鋼管製腔室內時」所產生之 鋼管製腔室內的無效空間（dead space )，可實現更小型 的螺旋壓縮機。 然而，雖然上述的實施例皆採用雙軸型的螺旋壓縮機 來作說明，但即使是單軸型螺旋壓縮機也同樣能適用。說 明單軸型螺旋壓縮機的範例，該單軸型螺旋壓縮機具備： 由齒形部與軸部所構成的螺旋轉子、和與該螺旋轉子嚙合 的柵門轉子、和支承前述螺旋轉子之軸部的低壓側軸承與 高壓側軸承、和支承前述柵門轉子之軸部的軸承、和驅動 「直結於前述螺旋轉子的軸部之該螺旋轉子」的馬達、和 收容著該馬達的馬達殼體、及收容著前述螺旋轉子與前述 柵門轉子的主殼體。使在上述單軸型螺旋壓縮機的場合中 ’也具備用來收容前述馬達殻體與前述主殼體的鋼管製腔 室’且該鋼管製腔室是由可在軸方向上分割的低壓側腔室 與闻壓側腔室所構成。接著，只要構成：由設於鋼管製腔 室內面的凸緣'和設於前述主殻體或者馬達殻體的凸緣、 及设於上述凸緣間的密封要件，將前述鋼管製腔室內的空 間分隔成低壓部側的空間與高壓部側的空間，便能獲得與 -20- 201040393 上述實施例相同的效果。 此外，上述的實施例皆爲：設於外殼41之內面的凸 緣、與設於主殻體或者馬達殼體的凸緣，隔著密封要件30 而連接之構造的範例，亦即，是將凸緣配置於外殼的外氣 側與冷媒側之兩側的構造。但是，即使是藉由設於低壓側 腔室與高壓側腔室之外面端部的凸緣，將設於主殻體或馬 達殼體的凸緣與密封要件一起夾入，以取代設於外殼內面 0 的凸緣，也可以將鋼管製腔室內分隔成低壓側空間3 1與 高壓側空間3 2。只要形成上述的實施例，便不需要外殼內 面的凸緣，可形成更簡素的構造。 根據上述的本實施例，由於將壓縮機構部收納於鋼管 製腔室內，故能達成螺旋壓縮機之大幅度的小型輕量化。 不僅如此，鋼管製腔室是可分割，而構成可隔著密封要件 而將鋼管製腔室內的空間分隔成低壓部與高壓部。因此， 在習知的鋼管製腔室構造中極爲困難的壓縮機，除了形成 Q 半密閉化之外，還能將電動機配置於低壓側’並將油分離 器配置於高壓側，可獲得具有良好的維修保養性之小型輕 量且高信賴性的螺旋壓縮機。 【圖式簡單說明】 第1圖：是顯示本發明實施例1之螺旋壓縮機的縱剖 面圖。 第2圖：是顯示本發明實施例2之螺旋壓縮機的縱剖 面圖。 -21 - 201040393 第3圖：是顯示本發明實施例3之螺旋壓縮機的縱剖 面圖。 第4圖：是顯示本發明實施例4之螺旋壓縮機的縱剖 面圖。 第5圖：是顯示本發明實施例5之螺旋壓縮機的縱剖 面圖。 第6圖：是顯示本發明實施例6之螺旋壓縮機的俯視 剖面圖。 第7圖：是顯示本發明實施例7之螺旋壓縮機的俯視 剖面圖。 【主要元件符號說明】 1 馬達殻體 2 :主殼體 3 :排放殻體 4 :馬達 4a :定子 4b :轉子 5 :圓筒狀鏜孔 6 :吸入埠 7、8、1 〇 :滾子軸承（低壓側軸承） 9、1 1 :滾子軸承（高壓側軸承） 1 2、1 3 :滾珠軸承（高壓側軸承） 14 :公轉子（螺旋轉子） -22- 201040393 1 5 :母轉子（螺旋轉子） 1 6 :軸承室 1 7 :遮蔽板 1 8、1 9 :供油通路 2 0 :油池 2 1 :低壓側腔室 22、23 :高壓側腔室（22 :第1高壓側腔室，23 :第 0 2高壓側腔室） 24、 25、 26、 27， 28， 29:凸緣 2 5 a :外氣側 25b :冷媒側 3 〇 :密封要件 3 1、3 2 :空間 3 3 :吸入口 3 4 :濾篩 Q 3 5 :排放通路 3 6 :排放配管 3 7 :鏡板 3 8 :除霧器 3 9 :氣體通路 4 0 :排放口 41 :外殼 42 :電源端子 43 :變流器 -23- 201040393 4 4 :外部電源 45 、 46 、 47 :中心軸 -24[Technical Field] The present invention relates to a screw compressor for compressing a fluid, and more particularly to a screw compressor which is suitable as a "refrigeration cycle for an air conditioner or a refrigerator". [Prior Art] A spiral compressor has a spiral rotor having a "curved surface formed by 0-dimensional (three-dimensional) 0" as a compression mechanism portion. For this reason, the casing for accommodating the compression mechanism portion is generally cast iron which can be formed into a complicated shape. Cast iron, which is usually used as a casing for a compressor, has a lower strength than steel for pressure piping. In the case where the design pressure is the same, the material thickness of the cast iron casing must be thicker than that of the steel casing, thus having the disadvantage of an increase in the quality of the compressor. In addition, the screw compressor must separate the lubricating oil contained in the exhaust gas. Therefore, most of the oil separator is integrally formed on the compressor, and the oil separator is also made of cast iron, and has a compression and contraction machine. The subject of a significant increase in quality. In addition, as in a rotary compressor or a scroll compressor, the compression mechanism unit is housed in a steel pipe chamber to reduce the size and weight of the screw compressor. For example, as shown in Patent Document 1, a structure in which a compression mechanism portion of a screw compressor is housed in a steel pipe chamber is formed. The device of the prior art uses a structure in which the pressure in the steel tube chamber is high. Further, in other conventional examples, a screw compressor having a structure in which a cast iron compression mechanism portion is housed in a steel pipe chamber and welding between a steel pipe and a dissimilar metal of cast iron is performed is considered. Indoor sub--5- 201040393 is divided into a low pressure section and a high pressure section. [Patent Document 1] U.S. Patent No. 4,545,742 [Disclosure] [Problem to be Solved by the Invention] By using a steel tube chamber in a screw compressor, it is possible to reduce the size and weight. However, the conventional screw compressor has the following problems. In the case where the pressure in the steel pipe chamber forms a high pressure after the refrigerant gas is compressed, the cooling of the motor is performed by the high-pressure, high-temperature refrigerant gas. For this reason, there is a risk that the motor is overheated during the operation of the compressor, and there is a problem from the viewpoint of reliability. Conversely, it is also possible to cause the pressure in the steel tube chamber to form a low pressure before the refrigerant gas is compressed. However, in a structure in which a low pressure is formed in a steel pipe chamber, it is difficult to provide an oil separator in a steel pipe chamber, and it is necessary to separately install the oil separator and the compressor, and the entire compressor is enlarged. Shortcomings. In addition, in the case of "a structure for separating a low pressure portion and a high pressure portion by welding between a dissimilar metal of a steel pipe and a cast iron", welding between dissimilar metals is possible, but if the most appropriate welding condition is not set, The crack is generated due to insufficient melting of the welded portion, and there is a problem that the gas is leaking or the high-pressure refrigerant gas leaks toward the low pressure portion, causing deterioration in performance. Moreover, in this configuration, it is necessary to weld the entire circumference of the steel tube chamber to be divided into a low pressure portion and a commercial pressure portion' to lengthen the welding length. Therefore, there is a problem that "the potential for cracking in the welded portion is increased", and in particular, it is difficult to apply to a large-capacity compressor. In addition, ― 6 - 201040393 has a structure in which it is difficult to perform maintenance such as bearing exchange. As described above, in the structure in which the compression mechanism portion of the screw compressor is housed in the steel pipe chamber, it is difficult to arrange the motor on the low pressure side and arrange the oil separator because the compressor is semi-hermetic. On the high pressure side. That is, the steel tube chamber structure is an excellent structure for small size and light weight, and on the contrary, it has a problem of poor maintenance and reliability. 0 The object of the present invention is to provide a screw compressor that is small and lightweight, has excellent maintenance, and is highly reliable. [Means for Solving the Problem] In order to achieve the above object, the present invention is a screw compressor including a spiral rotor composed of a toothed portion and a shaft portion, and a low pressure side bearing and a high pressure side that support a shaft portion of the spiral rotor. a bearing, a driving motor that is directly coupled to the shaft portion of the spiral rotor, a motor housing that houses the motor, a main housing that houses the spiral rotor and the low-pressure side bearing, and a spiral rotor that houses the spiral rotor a discharge casing of a high-pressure side bearing, comprising: a steel pipe chamber for accommodating the motor casing, the main casing and the discharge casing; the steel pipe chamber is divided by an axial direction a low-pressure side chamber and a high-pressure side chamber; a flange provided on an inner surface of the steel pipe chamber; a flange provided on the main casing or the motor casing; and a flange disposed between the flange Sealing element configuration. The space inside the steel pipe chamber is divided into a space on the low pressure portion side and a space on the high pressure portion side. Here, the low-pressure side chamber and the high-pressure side chamber may be formed in the form of 201040393: the outer chamber of the steel tube chamber is sealed by means of a flange formed by the outer ends of the outer surfaces of the two. structure. Further, the high pressure side chamber is further divided into two portions in the axial direction, and the first high pressure side chamber connected to the low pressure side chamber and the second high pressure connected to the first high pressure side chamber Preferably, the first chamber and the second high pressure chamber are formed by combining flanges provided at the outer ends of the two surfaces to seal the outside air in the steel tube chamber. structure. Further, the space in the steel pipe chamber may be partitioned into a space on the low pressure portion side and a space on the high pressure portion side by a flange provided on the inner surface of the high pressure side chamber and a main flange provided in the main casing. a flange is connected via a sealing member; a flange provided on the inner surface of the high-pressure side chamber is connected to a flange provided on the motor casing via a sealing member; and a flange provided on the inner surface of the low-pressure chamber The flange provided in the main casing is connected via a sealing member, or the flange provided on the inner surface of the low-pressure chamber is connected to a flange provided in the motor casing via a sealing member. Preferably, the central axis of the outer casing constituting the steel pipe chamber is disposed in the horizontal direction. In the present invention, the spiral rotor is preferably constituted by at least a pair of male and female rotors that mesh with each other. Further, the actuating fluid compressed by the screw compressor of the present invention is a refrigerant used in a refrigerating cycle, and the refrigerant is a refrigerant using "the cooling capacity per unit volume flow rate is 70% or less of the refrigerant R407C", as long as The number of teeth of the male rotor of the spiral rotor is set to 4 teeth, the number of teeth of the female rotor is set to 6 teeth, and the drive motor directly connected to the male rotor is driven by a current transformer, and the global warming coefficient can be used -8 - 201040393 Refrigerant (low GWP refrigerant). Further, preferably, the central axis of the steel tube chamber is disposed between the central axis of the male rotor and the central axis of the female rotor. The screw compressor described above is also applicable to a member having a gate rotor that meshes with a spiral rotor and a bearing for supporting a shaft portion of the gate rotor. a low-pressure side bearing and a high-pressure side bearing that support a spiral rotor composed of a toothed portion and a shaft portion, and a gate rotor that meshes with the helical rotor, and a shaft portion that supports the spiral rotor, and supports the gate a bearing of a shaft portion of the rotor, a motor that "straights the shaft portion of the spiral rotor and drives the spiral rotor", a motor housing that houses the motor, and a main body that houses the spiral rotor and the gate rotor Another aspect of the present invention provides a screw compressor including a steel pipe chamber for accommodating the motor casing and the main casing, wherein the steel pipe chamber is a low pressure side that can be divided in the axial direction. a chamber and a high-pressure side chamber, and a flange provided on an inner surface of the inner surface of the tantalum steel tube chamber is provided on a flange of the main casing or the motor casing, and is disposed between the flanges The space for partitioning the space inside the steel pipe chamber into the space on the low pressure portion side and the space on the high pressure portion side are provided with a "spiral rotor, a bearing for supporting the spiral rotor, and driving the screw" A screw compressor of a motor of a rotor, a motor case in which the motor is housed, and a main casing that houses the spiral rotor, and another feature of the present invention, further comprising: a housing for housing the motor housing The steel pipe chamber of the main casing 'the steel pipe chamber is a space which can be divided upwardly on the axis -9 - 201040393' and is divided into the above-mentioned separable steel pipe chamber, and is partitioned into a low pressure portion side via a sealing member Space and space on the side of the high pressure section. [Effect of the Invention] According to the present invention, a steel pipe chamber for accommodating a motor casing and a main casing is provided, and the steel pipe chamber is divided in the axial direction, and the space in the separable steel pipe chamber is In the structure in which the space between the low pressure portion side and the high pressure portion side can be separated by the sealing member, it is possible to obtain a screw compressor that is compact and lightweight, has excellent maintenance, and is highly reliable. . [Embodiment] Hereinafter, specific embodiments of the present invention will be described based on the drawings. In the drawings, the parts indicating the same drawing numbers refer to the same or equivalent parts. [Embodiment 1] Fig. 1 shows Embodiment 1 of the present invention. Although in the following description, a "two-shaft type screw compressor having two male and female spiral rotors" is used as an embodiment, the present invention is not limited to a two-shaft type screw compressor, and a single-screw type rotor The uniaxial screw compressor is also applicable to 0. As shown in Fig. 1, the screw compressor has a motor housing 1, a main casing 2, and a discharge casing 3 which are connected to each other. The motor housing 1 houses a drive motor 4 for "compressing the compression mechanism portion", and is fixed to the main casing 2 by means of a bolt or the like -10-201040393. The main casing 2 is formed with a cylindrical bore 5 and a suction port 6 for introducing refrigerant gas into the cylindrical bore 5. In the cylindrical cymbal L 5, the roller bearings 7, 8, 9 (7, 8 are low-pressure side bearings, 9 is a high-pressure side bearing) and the ball bearing 1 2 (high-pressure side bearing) is supported as a rotatable revolution. The sub-fourteen and the female rotor (not shown in the drawing) are accommodated in mesh with each other. The shaft of the male rotor 14 is directly connected to the motor 4. The discharge case 3 houses a roller bearing 9 and a ball bearing 12 (high-pressure side bearing), and these bearings are fixed to the main casing 2 by means of bolts or the like. Further, a shielding plate 17 for closing the "storage roller bearing 9 and the bearing chamber 16 of the ball bearing 12" is attached to one end of the discharge casing 3. In the main casing 2 and the discharge casing 3, oil supply passages 18 and 19 are formed to constitute an oil pool 20 that communicates with "the lower portions of the high pressure side chambers 22, 23" and the respective bearing portions. The motor case 1, the main case 2', and the discharge case 3 are housed in a steel tube chamber in which "the structure can be divided in the axial direction". The steel control chamber is composed of a low pressure side chamber 2 1 and a high pressure side chamber 2 2, 2 3 , and the flanges 24, 25, 26, 27 formed at the ends of the outer surfaces of the chambers are sealed by The components (not shown in the drawing) are connected by means of bolts or the like, and the outer chamber of the steel pipe chamber is sealed with an external air, and a structure that can be divided in the axial direction is formed. The high pressure side chamber is divided into two portions in the axial direction, and the first high pressure side chamber 22 connected to the low pressure side chamber and the second high pressure connected to the first high pressure side chamber 22 The side chamber 23 is constructed. The flange 29 formed in the main casing 2 and the flange 28 formed in the inside of the high pressure side chamber 22 are connected by bolts or the like via the sealing member 30. -11 - 201040393 In this manner, the spaces 31 and 32 in the steel pipe chamber are partitioned such that the space 31 becomes a low pressure side space, and the space 3 2 becomes a high pressure side space. Next, the flow of the refrigerant gas and the oil will be described. The low-temperature and low-pressure refrigerant gas sucked from the suction port 3 3 provided in the low-pressure side chamber 21 is a gas that is collected between the motor 4 and the motor casing 1 after the foreign matter is collected by the sieve 34. The motor and the air gap are "air-gap" between the "motor stator 4a and the rotor 4b" to cool the motor 4. The cooled refrigerant gas is sucked into the suction chamber formed by the main casing 2, and is sucked into the suction chamber formed by the tooth surface that is meshed by the male and female spiral rotors and the main casing 2. Thereafter, the male rotor 14 connected to the motor 4 is sealed to a compression chamber "made by the meshing tooth surface of the male and female spiral rotors and the main casing 2", and is simplified by the JS chamber. It is reduced and slowly compressed to become a high-temperature, high-pressure refrigerant gas. The compressed refrigerant gas is discharged to the mirror plate 37 constituting the high pressure side chamber 23 through the discharge passage 35 and the discharge pipe 36 constituted by the discharge casing 3. In the compression reaction acting on the male and female spiral rotors during compression, the radial load is supported by the roller bearings 7, 8, 9 and the thrust load is supported by the ball bearings 12. The lubricating and cooling oil for the bearing is supplied from the oil pool 20 provided in the lower portion of the high pressure side chambers 22 and 23 through the oil supply passages 18 and 19 which are "connected to the respective bearing portions" and is subjected to differential pressure. Oil supply. The oil after the oil supply is discharged together with the compressed refrigerant gas toward the mirror plate 37 constituting the high pressure side chamber 23. The oil contained in the compressed refrigerant gas is formed by the trap type oil separator of "the mist eliminator 38 provided in the high pressure side chamber 23, etc." after the primary separation by the collision of the mirror plate 37. Separate ' -12- 201040393 and store in the oil "disposed on the lower part of the high pressure side chambers 22, 23". The compressed refrigerant gas 'is passed through the gas passage 3 9 at the upper portion of the pressure side chamber 22 and is slid by the discharge port 40 provided in the high pressure side chamber 22 in a conventional screw compressor 'motor housing丨, main casing 2 The casing 3 is sealed by being connected to each other to have a function of "maintaining a pressure-resistant casing inside." Further, the 'screw compressor' has a complicated structure in order to accommodate a spiral having a complicated three-dimensional (three-dimensional) curved surface and a slide valve for capacity control. Therefore, the housing of the screw compressor is generally cast iron which has a "formable shape". In the case where cast iron is used as the casing, the steel material used for the pressure piping is lower than the material thickness which has to be increased for maintenance, and the quality of the compressor tends to increase. In the above case, in the structure of the present embodiment, since the internal pressure is maintained by the steel pipe, the main casing 2 made of cast iron has the main purpose of accommodating the compression Q portion. Therefore, it is possible to obtain a compact and lightweight screw compressor by minimizing the quality of the cast iron casing. On the other hand, in the embodiment of Fig. 1, the central axis constituting the steel tube chamber is disposed in the horizontal direction. In the case where the steel tube chamber is placed in the flat direction, since the center of gravity is formed, it has good stability when being carried out and loaded. However, the present invention is not limited to the arrangement of the steel chamber in the horizontal direction, and even if the central axis other than the chamber constituting the steel pipe is placed in the vertical direction, the "iron for storing the compressor" can be used. The quality of the body is suppressed to a minimum. I 20 body discharge and discharge pressure "with rotor shell is a strong shell for the chamber mechanism to make the shell to the water shrinking machine control shell" Construction Department-13- 201040393 The cast iron shell is housed in the steel tube cavity The conventional spiral compressor in the room is formed by: the pressure in the chamber of the steel pipe is a structure composed of any one of a low pressure before compression of the refrigerant gas or a high pressure after compression of the refrigerant gas; or by a steel pipe and a cast iron The dissimilar metal is welded 'and separated into a high pressure chamber and a low pressure chamber. In the case where the steel pipe chamber is low pressure, the refrigerant gas compressed by the spiral rotor must be directly discharged to the outside of the steel pipe chamber. Therefore, it is difficult to install the oil separator in the steel pipe chamber. Therefore, an oil separator must be additionally provided, which is difficult to miniaturize. In the case where the steel pipe chamber is at a high pressure, the cooling of the drive motor 4 is performed by the high-pressure, high-temperature refrigerant gas. The drive motor 4 is overheated during the operation of the compressor, which has a problem of reliability. Further, although the insulating material of the driving motor 4 is made of a resin material, the heat resistance level of these resin materials must also be improved. In the case where the structure of "separating into a high pressure chamber and a low pressure chamber" is formed by welding between dissimilar metals, if the welding condition is improperly set (meaning that it is not the most suitable), the welding portion between the dissimilar metals is caused. The crack caused by the insufficient melting causes the high-pressure refrigerant gas to leak to the low-pressure portion, resulting in a decrease in performance. In addition, in order to separate into a high pressure chamber and a low pressure chamber, it is necessary to weld the steel tube chamber all the way, and the larger the capacity of the compressor, the longer the welding length, and the higher the risk of the high pressure refrigerant gas leaking to the low pressure portion. . Therefore, this configuration is not suitable for a large-capacity compressor. With respect to the above-described situation, by forming the structure of the present embodiment, since the inside of the steel pipe chamber is formed by the "separator sealing member 30 and is divided into the partial low pressure-14-201040393", the driving motor 4 can be disposed. On the low pressure side of the steel control chamber, the oil separator is placed on the high pressure side of the steel tube chamber. By constituting the above description, it is possible to achieve both the cooling of the motor 4 by the low-pressure, low-temperature refrigerant gas and the arrangement of the oil separator in the steel chamber. In the present embodiment, the oil separator has a structure in which "collision type oil separation by the mirror plate 37" and "separation type oil separation by the mist eliminator 38" are formed. In addition, since the structure of "the low pressure portion and the high pressure portion are separated by the sealing member 30" is formed, the airtightness is excellent, and the risk of "high pressure refrigerant gas leaking to the low pressure portion and degrading performance" is extremely low. In addition, since the steel tube chamber can be divided into the low pressure side chamber 2 1 and the high pressure side chambers 22 and 23, the maintenance of the bearing replacement and the like can be easily performed (Example 2). Embodiment 2 of the present invention is shown. Similarly to the embodiment Q of Fig. 1, the steel tube chamber is composed of the low pressure side chamber 21 and the high pressure side chambers 22, 23, and the flanges formed in the respective chambers are connected by means of bolts or the like. 24, 25, 26, 27", the low-pressure side chamber 21 and the high-pressure side chambers 22, 23 are in a sealed relationship with each other', and a structure in which the sealing structure can be formed in the external air and the division can be formed. In the present embodiment, the flange 29 formed in the motor casing 1 and the flange 28 formed inside the high pressure side chamber 22 are connected by bolts or the like via the sealing member 30, which is different from the implementation. example 1. In the present embodiment, the spaces 31, 32 in the steel control chamber are divided into: the space 3 1 becomes a low -15 - 201040393 pressure side space, and the space 32 becomes a high pressure side space 'can be taken into consideration · low pressure, low temperature The cooling of the driving motor 4 by the refrigerant gas and the arrangement of the oil separator into the steel pipe chamber further improve the airtightness of the low pressure portion and the high pressure portion, and the structure is easy to maintain. [Embodiment 3] Fig. 3 shows Embodiment 3 of the present invention. As in the embodiment of Fig. 1, the steel tube chamber is composed of the low pressure side chamber 21 and the high pressure side chamber 22, and the flanges 24, 25 formed in the respective chambers are connected in a sealed relationship by means of bolts or the like. And constitute a separable structure. In the present embodiment, the flange 29 formed in the main casing 2 and the flange 28 formed in the inside of the low-pressure side chamber 21 are connected by bolts or the like via the sealing member 30, and the space in the chamber of the steel pipe is formed. 3 1 and 3 2 are divided into: space 3 1 becomes a low-pressure side space, and space 3 2 becomes a high-pressure side space. In the present embodiment, both the low-pressure and low-temperature refrigerant gas are cooled to the driving motor 4, and the oil separator is disposed in the steel pipe chamber, and the low-pressure portion and the high-pressure portion are excellent in airtightness, and Maintenance is easy to construct. In the present embodiment, since "the compressor can be disassembled and assembled even if the high pressure side chamber 22 is not divided", it is not required to be connected between the high pressure chambers as compared with the embodiment in which the high pressure side chamber 22 must be divided. The flange and sealing requirements have the effect of obtaining a "simple and more reliable compressor." [Embodiment 4] Fig. 4 shows Embodiment 4 of the present invention. Similarly to the embodiment-16-201040393 of Fig. 1, the steel tube chamber is composed of the low pressure side chamber 21 and the high pressure side chamber 22, and the flange 24 formed in each chamber is formed by means of bolts or the like. Connected into a sealed relationship to form a separable configuration. In the present embodiment, "the flange 29 formed in the motor casing 1 and the flange 28 formed in the lower portion of the low pressure side chamber 2 are connected by bolts or the like via the sealing member 30". The embodiments are different. In the present embodiment, the spaces 3 1 and 3 2 in the steel pipe cavity are also partitioned such that the space 3 1 becomes the low pressure side space Λ the space 3 2 becomes the high pressure side space. Thereby, both the low-pressure and low-temperature smear gas cooling of the driving motor 4 and the arrangement of the oil separator in the steel pipe cavity are formed, and the low-pressure portion and the high-pressure portion are formed to have good airtightness and are easily repaired. Maintenance structure. Further, in the present embodiment, as in the third embodiment, since the compressor can be disassembled even if the high pressure side chamber 22 is not divided, the high voltage "necessary when the high pressure side chamber 22 is separated" is not required. Sealing requirements between chambers. [Embodiment 5] Fig. 5 shows Embodiment 5 of the present invention. As in the first embodiment, the steel tube chamber is composed of the low pressure side chamber 21 and the high pressure side chamber 22 23, and the flanges, 25, 26 formed in each chamber by means of bolts or the like are used. 27 is connected in a sealed relationship to form a separable configuration. In the present embodiment, the flange 25' integral with the outer casing 41 is disposed on both sides of the gas side 25a and the refrigerant side 2 5b outside the outer casing 41. In the present example, since the inside of the outer casing 41 does not need to be additionally provided with a flange for connection with the casing, the chamber can be divided into a low-pressure chamber 25 5 by using a simpler structure. 2 4 In the span of the convex side -17- 201040393 space 31 and the high pressure side space 32. In the present embodiment, the "mounting flange 29 formed in the main casing 2" and the "flange 25 formed in the high pressure side chamber 22" are connected by bolts or the like, but the following structures are also formed. The same effect can be obtained: "the flange formed in the motor casing and the flange formed in the high pressure side chamber", or "the flange formed in the main casing and the low pressure side cavity" are connected by bolts or the like. "Flange of the chamber"; or "a flange formed in the motor housing and a flange formed in the low pressure side chamber". [Embodiment 6] Fig. 6 shows Embodiment 6 of the present invention. Similarly to the embodiment of Fig. 1, the motor casing 1, the main casing 2, and the discharge casing 3 are housed in "a chamber that constitutes a separable steel pipe." In the present embodiment, a refrigerant having a cooling capacity per unit volume flow rate of 70% or less of the refrigerant R4 0 7 C is used as an example of a compressed actuating refrigerant. In the present embodiment, the spiral rotor housed in the main casing 2 is constituted by the following conditions: the number of teeth of the male rotor i 4 is 4 teeth 'the number of teeth of the female rotor I5 is 6 teeth; and is driven by the current transformer 43 The drive motor 4 is "straight to the shaft portion of the male rotor 14". As for the refrigerant used in the air conditioner or the refrigerator, there are a large number of types such as R4 1 〇A, R407C, R134a, ammonia, carbon dioxide, and the like, and the "cooling ability per unit volume of fluid" of each type is also different. In the case where the cooling capacity required for the air conditioner or the refrigerator is the same, if the refrigerant having a large cooling capacity per unit volume is used, the theoretical discharge amount of the compressor is reduced, so that the compressor can be miniaturized. On the other hand, in the case of using a refrigerant having a small cooling capacity per unit volume in -18-201040393, the compressor will become larger. For example, when the cooling capacity per unit volume flow rate of the refrigerant R407C is set to 100, R410A is about 15 〇 and Rl 3 4a is about 65. For this reason, in the case where the same cooling ability is to be obtained, the compressor is enlarged as compared with R407C or R410A', if R1 34a is used as the refrigerant. Although the recently-recognized refrigerant with low global warming coefficient (low-GWP refrigerant), most of the zeros are the same as R 1 3 4a, and the cooling capacity is small for each unit volume flow, but only according to this embodiment. For example, even if the above-described low GWP refrigerant is used, the weight of the compressor can be reduced. Although the number of teeth of the male rotor 14 and the female rotor 15 of the screw compressor is 5 teeth and 6 teeth, and 5 teeth and 7 teeth, respectively, in the case where the rotor diameter is the same, the teeth are smaller because the number of teeth is smaller. The larger the area of the groove, the tendency to increase the theoretical amount of emissions. In the present embodiment, even in the case of using a refrigerant having a small cooling capacity per unit volume flow rate, the combination of the number of teeth of the male rotor 14 and the female rotor 15 is set to 4 teeth and 6 teeth, respectively, and the converter 43 is used. The drive motor 4' that is directly coupled to the shaft portion of the male rotor 4 can be driven to increase the speed. According to the present embodiment, it is possible to realize a large size and weight reduction for a compressor that uses "the external power source 44 and is driven at a constant speed". [Embodiment 7] Embodiment 7 of the present invention is shown in Fig. 7. With the first! EMBODIMENT OF THE FIGURES The same as the 'motor case 1, the main case 2, and the discharge case 3 are housed in a "divided steel tube chamber" of ""19-201040393". The present embodiment is a central shaft 47 constituting a steel tube chamber, and is disposed at: a male rotor 14; and a central shaft 45 of the driving motor 4 directly connected to the male rotor 14; and a central axis of the female rotor 15 Between 46. In the two-shaft type screw compressor, two axes of "the central axis of the male rotor 14" and "the central axis of the female rotor 15" are inevitably present. By arranging the central axis of the steel tube chamber between the two shafts, it is possible to reduce the dead space in the steel tube chamber generated when the cast iron casing is placed in the steel tube chamber. A smaller screw compressor can be realized. However, although the above embodiments have been described using a two-shaft type screw compressor, even a single-shaft type screw compressor can be applied. An example of a uniaxial type screw compressor comprising: a spiral rotor composed of a tooth portion and a shaft portion, a gate rotor engaged with the spiral rotor, and a shaft supporting the spiral rotor a low-pressure side bearing and a high-pressure side bearing, a bearing for supporting a shaft portion of the gate rotor, and a motor for driving the spiral rotor that is directly connected to a shaft portion of the spiral rotor, and a motor housing that houses the motor And a main casing that houses the spiral rotor and the gate rotor. In the case of the above-described uniaxial screw compressor, 'there is also a steel pipe chamber for accommodating the motor casing and the main casing, and the steel pipe chamber is a low pressure side which is separable in the axial direction. The chamber is formed by the chamber and the squeezing side chamber. Next, the flanges ' provided on the inner surface of the steel pipe chamber, the flanges provided in the main casing or the motor casing, and the sealing members provided between the flanges are configured to be inside the steel pipe chamber. The space is divided into the space on the low pressure side and the space on the high pressure side, and the same effect as the above embodiment of -20-201040393 can be obtained. Further, the above-described embodiments are examples of a structure in which a flange provided on the inner surface of the outer casing 41 and a flange provided on the main casing or the motor casing are connected via the sealing member 30, that is, The flange is disposed on the outer side of the outer casing and the sides of the refrigerant side. However, even if the flange provided at the end of the outer surface of the low pressure side chamber and the high pressure side chamber is fitted with the flange of the main housing or the motor housing, instead of being provided in the outer casing The flange of the inner surface 0 can also divide the steel tube chamber into a low pressure side space 31 and a high pressure side space 3 2 . As long as the above embodiment is formed, the flange inside the outer casing is not required, and a simpler construction can be formed. According to the present embodiment described above, since the compression mechanism portion is housed in the steel pipe chamber, it is possible to achieve a large size and weight reduction of the screw compressor. Moreover, the steel tube chamber is separable, and the space inside the steel tube chamber can be partitioned into a low pressure portion and a high pressure portion via a sealing member. Therefore, in the compressor which is extremely difficult in the conventional steel pipe chamber structure, in addition to forming the Q semi-hermetic, the electric motor can be disposed on the low pressure side and the oil separator can be disposed on the high pressure side, which is good. Small, lightweight and highly reliable screw compressor for maintenance. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a longitudinal sectional view showing a screw compressor according to a first embodiment of the present invention. Fig. 2 is a longitudinal sectional view showing a screw compressor according to a second embodiment of the present invention. -21 - 201040393 Fig. 3 is a longitudinal sectional view showing a screw compressor according to a third embodiment of the present invention. Fig. 4 is a longitudinal sectional view showing a screw compressor according to a fourth embodiment of the present invention. Fig. 5 is a longitudinal sectional view showing a screw compressor according to a fifth embodiment of the present invention. Fig. 6 is a plan sectional view showing a screw compressor according to a sixth embodiment of the present invention. Fig. 7 is a plan sectional view showing a screw compressor of a seventh embodiment of the present invention. [Main component symbol description] 1 Motor housing 2: Main housing 3: Discharge housing 4: Motor 4a: Stator 4b: Rotor 5: Cylindrical bore 6: Suction 埠 7, 8, 1 〇: Roller bearing (Low-pressure side bearing) 9, 1 1 : Roller bearing (high-pressure side bearing) 1 2, 1 3 : Ball bearing (high-pressure side bearing) 14 : Male rotor (spiral rotor) -22- 201040393 1 5 : Female rotor (spiral Rotor) 1 6 : Bearing chamber 1 7 : shielding plate 1 8 , 1 9 : oil supply passage 20 : oil pool 2 1 : low pressure side chamber 22, 23: high pressure side chamber (22: first high pressure side chamber , 23 : 0 2 high pressure side chamber) 24, 25, 26, 27, 28, 29: flange 2 5 a : outer air side 25b: refrigerant side 3 〇: sealing element 3 1 , 3 2 : space 3 3 : suction port 3 4 : sieve Q 3 5 : discharge passage 3 6 : discharge pipe 3 7 : mirror plate 3 8 : defogger 3 9 : gas passage 4 0 : discharge port 41 : outer casing 42 : power terminal 43 : variable flow -23- 201040393 4 4 : External power supply 45, 46, 47: Center axis -24