201226813 六、發明說明 【發明所屬之技術領域】 本發明是關於一種，對作爲收容被設置在無塵室內的 曝光裝置等的空調對象的空間供給循環被精密調溫後的空 氣的精密空調機。 【先前技術】 液晶玻璃基板的曝光裝置的周邊環境，由於玻璃基板 會因溫度變化而熱膨脹，所以必須精密控制空調溫度（精 度 ±0.01 〜±0.1 °c)。 這類的曝光裝置等，是被設在無塵室內由隔壁等所形 成的空間內，並在無塵室的地板設置與無塵室用的空調機 不一樣的精密空調機，由精密空調機對作爲空調對象的空 間供給循環被精密溫度控制後的空調空氣。 該精密空調機是由冷凍循環所構成，以蒸發器將來自 空間的空氣冷卻成比設定溫度更低的溫度（例如17 °C )，再以再加熱電熱器將此加熱成設定溫度（例如23 °C ) ’並將此作爲空調空氣供給循環到空間內。 於此’作爲冷凍循環的蒸發器的吸熱部，爲了空調空 間內雖被設在無塵室內，可是作爲散熱部的冷凝器，是與 壓縮機一起作爲室外機設置在無塵室外，並以冷媒配管連 接散熱部與室外機，而構成氣冷式空調機。或是提案有： 以成爲散熱部的冷凝器作爲水冷式設置在無塵室的地板 時’在無塵室外設置冷卻水供給裝置，並以水冷配管連接 201226813 散熱部與冷卻水供給裝置的水冷式空調機等各整的型式 (專利文獻1 )。 可是，以再加熱電熱器將由蒸發器冷卻成比設定溫度 更低的溫度的空調空氣加熱成設定溫度的精密溫度控制， 會有電熱器的運轉成本增加的問題。 於此，除了如專利文獻2所提案的方式，利用冷凍循 環的熱氣體，使這個流到蒸發器，控制蒸發溫度的熱氣體 旁通管（byPaSS )之外，還提案有在蒸發器的空氣吹出側 另外設置再加熱用冷凝器，使熱氣體流到該再加熱用冷凝 器，並以其再加熱用冷凝器加熱以蒸發器所冷卻的空氣， 之後以再加熱電熱器進行精密溫度控制。 在該專利文獻2，由於是使熱氣體流到蒸發器來控制 蒸發溫度，並以再加熱用冷凝器溫度控制空調空氣，所以 可將再加熱電熱器的運轉成本降低到某一程度，可是在熱 氣體旁通管，要應答性佳且精密地控制冷凍循環的凝結溫 度或蒸發溫度是不可能的，因此再加熱電熱器的設置是不 可欠缺的。 另一方面，在專利文獻3，提案有在蒸發器的吹出側 設置再加熱用冷凝器，利用由空氣壓作動的三方比例控制 閥控制熱氣體的熱氣體的旁通量，可實現以再加熱用冷凝 器的回應性佳的溫度控制，藉此，不需要再加熱電熱器。 該專利文獻3，是以蒸發器將來自空間的空氣冷卻成 比設定溫度更低5 °C的溫度後馬上以再加熱用冷凝器加熱 到設定溫度者，由於再加熱電熱器並不需要，所以可抑制 -6 - 201226813 運轉成本。 [先行技術文獻] [專利文獻] [專利文獻1]曰本特開2000-283 500號公報 [專利文獻2]日本特開2009-2 1 6332號公報 [專利文獻3]日本特許第3 28 3 245號公報 【發明內容】 [發明所欲解決之課題] 然而，專利文獻1〜3中，在排熱回收用的冷凝器使 用冷卻水，在無塵室外另外設置冷卻水供給裝置，並且必 須進行以冷水配管連結冷卻水供給裝置與冷凝器側的散熱 部的作業。 尤其，最近的無塵室愈來愈大型化，設置曝光裝置等 的製程機器的潔淨區的高度將近l〇m，且地板的回流室的 高度也有5〜6m左右，而且其延伸地面面積也有數萬 m2，而形成在潔淨區內，設置有一個一個覆蓋多數個製程 機器的空間。使該各空間的熱散熱的散熱部被一個一個設 置在回流室，另一方面，由於在無塵室外設置有冷卻水供 給裝置，所以連接該冷水供給裝置與各散熱部的冷水配管 必然變長，而且連接也必須要高處作業’並且對於冷水配 管的保溫、漏水對策等必須要有極大的勞力。 又，專利文獻1〜3中，冷凍循環的負荷’是被設定 成對應最大空調負荷的能力，由於壓縮機的冷媒吐出壓是 201226813 以一定進行運轉’所以由蒸發器所吸熱的冷媒熱的排熱’ 控制流到冷凝器的冷卻水的循環量’可達成吸熱量與排熱 量的相匹配。可是’以冷卻水冷卻冷凝器的水冷式’是在 空調負荷大的時候’可適當控制在冷凝器的散熱量者’在 空調負荷少的時候，供給到冷凝器側的冷卻水流量極端變 少，成爲冷卻水流量的控制範圍以下會有穩定運轉變困難 的可能性。 亦即，作爲控制對象的空間的溫度控制’吸入空氣與 吹出溫度的溫度差爲± 2 °C以下時’空調負荷小的情況較 多。另一方面，供給到冷凝器的冷卻水溫度’是使用18 °C左右的冷卻水，由於冷卻水溫度相對於冷媒的凝結溫度 (7〇°C前後）低，所以空調負荷愈小’冷卻水量的控制變 的愈困難，且使冷凍循環穩定進行運轉，並配合空調負 荷，調整冷凝器側的排熱量變的困難。 於此，本發明的目的，是解決上述課題，並提供一種 可一面將冷凍循環的負荷保持在一定，一面對應控制對象 的空間的空調負荷，控制排熱量的精密空調機。 [解決課題用的手段] 爲了達成上述目的，本發明是一種，導入作爲被設置 在無麈室的空調對象的空間內的空氣，並將此形成設定溫 度，在前述空間內循環用的精密空調機，其特徵爲，具備 有： 冷凍循環，其具有：從壓縮機的吐出側到吸入側，依 201226813 序連接冷凝器、膨脹閥、蒸發器’並且使前述壓縮機的吐 出側的熱氣體流到前述蒸發器的熱氣體旁通管迴路； 熱回收部，其收容有前述冷凍循環的蒸發器’導入來 自前述空間的空氣，以前述蒸發器空調成設定溫度在前述 空間內循環；以及 散熱部，其被設在前述無塵室內，並且收容有前述冷 凍循環的冷凝器，且具備有利用無塵室內的空氣氣冷其冷 凝器，將前述冷凝器的凝結壓力保持在一定的散熱能力可 變風扇。 在本發明，前述冷凍循環、前述熱回收部、及前述散 熱部是被收容在同一個殼體內者。 在本發明，前述熱氣體旁通管迴路具備比例控制閥， 在前述熱回收部設有檢出以前述蒸發器所冷卻的空調空氣 的溫度的溫度感測器，以其溫度感測器的檢出値，控制前 述比例控制閥，藉此，可精密溫度控制由蒸發器所冷卻的 空調空氣者。 在本發明，在連結前述蒸發器的冷媒出口與壓縮機的 吸入側的冷媒配管，連接有將壓縮機的冷媒吸入壓力保持 在一定的吸入壓力調整閥，前述膨脹閥由溫度式膨脹閥構 成，在前述吸入壓力調整閥的上游側的配管設有前述溫度 式膨脹閥的感溫筒，藉此，可將在前述蒸發器的冷媒蒸發 壓力保持在一定者。 在本發明，在前述冷凝器到前述溫度式膨脹閥的高壓 側冷媒配管設有高壓感測器，另一方面以變頻裝置驅動前 -9 - 201226813 述散熱部的散熱能力可變風扇’並以變頻裝置控制前述散 熱能力可變風扇的旋轉’使得由前述高壓感測器所檢出的 冷媒的凝結壓力形成一定，藉此在冷凝器的冷媒凝結壓力 可保持在一定者。 在前述冷凝器與前述高壓感測器間的高壓側冷媒配管 有連接受液槽即可。 收容前述熱回收部與前述散熱部的殼體’被設在前述 無塵室的回流室即可。 [發明效果] 根據本發明，精密溫度控制空調對象的空間內的空氣 之際，對空調空間的空氣的蒸發器流入熱氣體，藉此精密 溫度控制空調空氣，由無塵室內設置的散熱部的冷凝器氣 冷相當於在蒸發器熱回收的熱，藉此進行排熱，而可穩定 進行精密溫度控制，進而可發揮在無塵室外不需設置室外 機、冷水源等極佳的效果者。 【實施方式】 [實施發明用的形態] 以下，依據添付圖面詳述本發明的適合的一實施的形 能。 首先，依據圖1說明對無塵室10;以及覆蓋被設置 在無塵室10內的曝光裝置等的製程機器11，作爲空調對 象的空間1 2的精密空調機1 3。 -10- 201226813 無塵室10是由：設有曝光裝置等的製程機器 且設有覆蓋這個的空間12的潔淨區16;被形成在 16的頂棚17的上方，對潔淨區16供給清淨空氣 空間1 8 ;以及被形成在潔淨區1 6的地面1 9的下 來自潔淨區16的空氣的回流室20。回流室20與 間18是以循環路21連結，在其循環路21設有無 空調機22,在供氣空間18內的頂棚17設有複數 淨區16吹出清淨空氣，且具有HEPA與風扇的風 器單元23。來自回流室20的空氣，是經由循環路 導入空調機22，在空調機22空調成設定溫度，其 氣從供氣空間18通過風扇過濾器單元23內的高性 器被清淨，以下向流吹初到潔淨區1 6。 在潔淨區16，是有在地面19上覆蓋製程機器 空間1 2，以精密空調機1 3對空間1 2內進行空調 密溫度控制製程機器11及製程機器11的周圍環境 在本發明，是將該精密空調機13設置在無塵 內，尤其是設置在回流室20內者。亦即，精密空言 是由：具備有將空間12內的空氣作爲回風（RA) 入，並對此進行精密空調，作爲供氣SA對空間1 供給循環的蒸發器26及循環風扇27的熱回收部 備壓縮機29等的機器部30:以及具備有冷凝器3 冷用的散熱能力可變風扇3 2的散熱部3 3所構成。 散熱部33是至少被設置在無塵室10,尤其是被設 室20者。又，如圖示，具備熱回收部28與壓縮機 1 1，並 潔淨區 的供氣 ，吸引 供氣空 塵室用 個對潔 扇過滤 21被 空調空 能過濾 1 1的 ，可精 〇 室 10 同機13 予以導 2進行 28 ;具 1及氣 於此， 在回流 ί 29等 -11 - 201226813 的機器部30;以及散熱部33是指：收容在一個殼體14 內作爲精密空調機13。該精密空調機13雖設在無塵室1〇 內的潔淨區16、回流室20等，可是尤其是設在回流室20 即可》 接著，依據圖2，說明構成精密空調機13的冷凍循 環25。 冷凍循環2 5是從壓縮機2 9的吐出側到吸入側，以冷 媒配管37依序連接散熱部33的冷凝器31、受液槽34、 作爲膨脹閥的溫度式膨脹閥3 5、熱回收部28的蒸發器 26、分離器36,再者，主要構成設有從壓縮機29的吐出 側到冷凝器31的高壓側冷媒配管37a分歧，使熱氣體流 到蒸發器26的熱氣體旁通管迴路40。 更進一步詳細說明該冷凍循環25。 在壓縮機29的吐出側的高壓側冷媒配管37a，設有 檢出壓縮機29的過負荷的壓力開關41，其高壓側冷媒配 管3 7a連接在冷凝器3 1的入口側。在冷凝器3 1的入口側 的高壓側冷媒配管37a連接有凝結壓力調整閥50。冷凝 器31是由鰭片&管子形成，在其冷凝器31設有散熱能力 可變風扇3 2，形成散熱部3 3。冷凝器3 1的出口側的高壓 側冷媒配管37a，是連接在受液槽34的上部，在受液槽 34的底部連接有高壓側冷媒配管37b。在從該受液槽34 到溫度式膨脹閥35的高壓側冷媒配管37b，連接有高壓 感測器42，並且在其下游的高壓側冷媒配管37b’連接有 檢出水分量的玻璃液面計43、除去冷媒中的水分的過濾 -12- 201226813 器乾燥器44、作爲止閥的無塡料閥（PacklESS valvE ) 45 ° 來自溫度式膨脹閥35的低壓側冷媒配管37c，連接 在蒸發器26的入口側。蒸發器26是由鰭片&管子所形 成，在其蒸發器26的出口側形成有設有循環風扇27的熱 回收部28。 從蒸發器26的出口側到分離器3 6的低壓側冷媒配管 37c依序連接壓力計46、外均壓導入閥47、過濾器48、 吸入壓力調整閥49。 溫度式膨脹閥35是由隔膜閥構成，詳細雖未圖示， 可是一方的隔膜室經由毛細管51連接感溫筒52，另一方 的隔膜室連接在外均管53而構成。感溫筒52是沿著蒸發 器2 6的出口側的低壓側冷媒配管3 7 c而設，外均管5 3是 連接在外均壓導入閥47。溫度式膨脹閥3 5，是利用從感 溫筒52經由毛細管5 1，作用在隔膜的一方的壓力（依據 蒸發器26的蒸發溫度的壓力）、與從外均管53作用在隔 膜的另一方的壓力（蒸發器26的蒸發壓力）的差壓，控 制閥開度（減壓度）。 此外，圖示的例子中，雖是以外平衡式的溫度式膨脹 閥3 5的例子進行說明，可是，也可使用內平衡式的溫度 式膨脹閥、或電動式膨脹閥。 吸入壓力調整閥49是輸入其下游側的冷媒壓力，調 整壓縮機29的吸入壓使其冷媒壓力成爲一定。 熱氣體旁通管迴路4〇是由：連接從壓縮機29的吐出 -13- 201226813 側到冷凝器3 1的高壓側冷媒配管3 "7a與蒸發器26的入 的旁通管配管54 ;與連接其旁通管配管的比例控制閥 所構成。又，在比例控制閥5 5的上游側的旁通管配管 連接有過濾器56。 在熱回收部28設有檢出以蒸發器26進行空調’並 用循環風扇27供給到空間12的供氣SA的溫度的溫度 測器58，而形成以該溫度感測器58的檢出値’控制熱 體旁通管迴路40的比例控制閥55。 又，散熱部33的散熱能力可變風扇32’是以變頻 置60旋轉數可改變地被驅動，在其變頻裝置60輸入高 感測器42的檢出値，並以變頻裝置60控制散熱能力可 風扇32的風量的方式，使高壓感測器42的檢出値成爲 定。 在該圖2的冷凍循環25，由壓縮機29所壓縮的冷 氣體（熱氣體），是以凝結壓力調整閥50進行壓力 制，主要通過冷凝器3 1，在這裡與利用散熱能力可變 扇32的旋轉被送風的回流室20內的空氣（23〜25 °C 右）進行熱交換而凝結，並在溫度式膨脹閥35被減壓 到蒸發器26。另一方面，來自壓縮機29的熱氣體的一 分，從熱氣體旁通管迴路4〇在比例控制閥5 5被流量 制，並與在溫度式膨脹閥35被減壓的氣液混相冷媒一 流到蒸發器26。在熱回收部28，導入來自空間12的回 RA’以蒸發器26冷卻這個，形成設定溫度±0.01〜±( °C，並作爲精密溫度控制的供氣S A供給到空間1 2。 P 55 54 利 感 氣 裝 壓 變 媒 控 風 左 流 部 控 起 風 1.1 -14- 201226813 在蒸發器26熱回收後的冷媒，作爲蒸發冷媒在吸 壓力調整閥49調整成壓縮機29的吸入壓力，經由分離 36被吸冬壓縮機29，且再次被壓縮作爲熱氣體被循環。 首先，在本發明，壓縮機29是以吸入壓力調整閥 調整成吸入壓力，並將過熱（比飽和氣體線更高5 t 溫度）的蒸發冷媒壓縮成預定的壓力，形成熱氣體。該 氣體是經由散熱部33的冷凝器31與熱氣體旁通管迴 40供給到蒸發器26的雙方。此時，高壓感測器42檢 冷凝器31的出口側的壓力，依據這個，變頻裝置60控 散熱能力可變風扇32的送風量，並且凝結壓力調整閥 調整流入冷凝器31的壓力。藉此，調整在冷凝器31的 交換量（排熱量），且不論熱氣體旁通管量的變動，在 凝器31的凝結壓力可保持在一定。在該冷凝器31的 結，由於是與回流室20內的空氣（23 °C〜25 °C左右） 行熱交換，所以凝結冷媒溫度與空氣的溫度差小，即使 熱量少的情況，也可以散熱能力可變風扇32的送風量 當控制散熱量。 接著，在熱回收部2 8的供氣S A的精密溫度控制 是藉由溫度感測器5 8控制比例控制閥5 5的開度，控制 熱氣體旁通管迴路40流入蒸發器26的熱氣體量的方式 進行。 該溫度感測器58，在圖雖表示檢出熱回收部28的 發器26的出口側的供氣SA的溫度的例子，可是也可 外設置檢出蒸發器26的入口側的回風RA的溫度的溫 入 器 49 的 熱 路 出 制 50 熱 冷 凝 進 散 適 從 來 蒸 另 度 -15- 201226813 感測器，並以其出入口的溫度感測器控制比例控制 55 〇 另一方面，溫度式膨脹閥35不論熱氣體旁通管量 調整減壓度，將蒸發器26的蒸發壓力保持在一定者。 即，蒸發器26的出口側溫度轉換成被封入在感溫筒52 的冷媒的壓力，將這個經由毛細管51導入溫度式膨脹 35的隔膜室的一方，同時經由外均管53將在蒸發器 被蒸發的冷媒的蒸發壓力導入溫度式膨脹閥35的隔膜 的另一方，並以兩隔膜室的差壓調整溫度式膨脹閥35 減壓度。 藉此，在蒸發器26，蒸發壓力被保持一定，在其 發器26的冷媒蒸發量，亦即，由於是以熱氣體流入量 制回風RA與冷媒的熱交換量，所以可進行對空調負荷 精密溫度控制。 在該冷凍循環25，雖是以散熱部33的冷凝器31 在熱回收部28的蒸發器26回收的熱，排熱到回流室 的空氣，可是，其排熱量，由於相對於在無塵室1〇的 調機1 3處理的熱量非常的小，所以可以空調機1 3的空 充分進行處理。因此，不需如以往，將爲了排熱，用的 外機、.冷水供給裝置等設置在無塵室1 〇外，並以冷媒 管連接的費事情形。 又，精密溫度控制之際，在熱氣體旁通管迴路40 以比例控制閥5 5配合回流室2 0的空調負荷控制其熱氣 流量，使其流入蒸發器26。此時，冷凝器31以高壓感 閥 亦 內 閥 26 室 的 蒸 控 的 將 20 空 調 室 配 體 測 -16- 201226813 器42的檢出値將凝結壓力控制在一定，同時，溫度式膨 脹閥35將蒸發壓力控制在一定，並且吸入壓力調整閥49 調壓縮機29的吸入壓力，使冷凍循環25可穩定進行運 轉。 又，比例控制閥55是依據回流室20的空調負荷變動 控制熱氣體量，在蒸發器26依據空調負荷，冷媒進行熱 回收。之後，在壓縮機29壓縮後的熱氣體導入散熱部33 的冷凝器31進行散熱。如此，由於在熱回收後進行散 熱，所以當空調負荷急遽變動之際，雖然在冷凍循環25 的熱回收量與散熱量的匹配容易變差，可是由於在冷凍循 環25設有受液槽34，所以冷凍循環25可穩定的運轉。 接著，在圖3的莫理爾線圖上說明該冷凍循環25。 圖3表示在冷媒使用R407C時的莫理爾線圖上的冷 凍循環，且是表示橫軸爲比熱焓 （kJ/kg)，縱軸爲絕 對壓力（MPa) ，Lg爲R4 07C的飽和氣體線，L1爲飽和 液線。 首先，壓縮機29的吸入冷媒，是由吸入壓力調整閥 49以點A ( 12°C、0.5MPa)導入到壓縮機29。該點A是 在比飽和氣體線Lg更充分高（+ 5 °C )的氣相側處於過熱 狀態’其冷媒氣體由壓縮機29被壓縮到點B ( 75 °C、 2.0MPa)。該點B的熱氣體，是被供給到冷凝器31側與 熱氣體旁通管迴路40側，在其分歧點，成爲下降到點C (1.7MP a)的壓力。被導入冷凝器31的熱氣體，藉由散 熱保持在點C的凝結壓力的狀態下通過飽和液線L1，從 -17- 201226813 氣液混相狀態被冷卻到成爲過冷卻液的點D ( 3 1 °C )。 該點D的過冷卻度可以溫度式膨脹閥3 5進行控制’ 由溫度式膨脹閥35被檢壓到點E ( 1 1°C、0.8MPO 。在 蒸發器26，可以該點E的壓力維持蒸發壓力。另一方 面，來自點C的熱氣體被導入到蒸發器26’壓力下降到 點F(0.8MPa)，成爲蒸發器26的蒸發壓力。在蒸發器 26，流入點F的熱氣體與由溫度式膨脹閥3 5被減壓到點 E爲止的冷媒，其冷媒與來自空間12的空氣（回風RA) 進行熱交換。藉此，冷媒成爲點G的狀態’從蒸發器26 的出口流入吸入壓力調整閥49的入口側’由其吸入壓力 調整閥49，從點G減壓調整到點A，導入到壓縮機29。 在該莫理爾線圖上的冷凍循環，點C到點D的熱量 爲冷凝器31的散熱量，點E到點G的熱量爲在蒸發器26 的熱量變化，冷凝器31的散熱量，是壓縮機29的熱量 (點G至點F的熱量）與蒸發熱量的合計熱量。 於此，熱氣體旁通管量〇%時，蒸發器26的蒸發熱量 成爲點E至點G的熱量，沒有空調負荷，熱氣體旁通管 量爲100%的時候，形成由冷凝器26進行壓縮機29的熱 量的散熱，蒸發器26的入口的冷媒的比熱焓是從點G 減去壓縮機29的熱量而成爲點Η。因此，相對於熱氣體 旁通管量 〇%〜1 00%，蒸發器26的入口的冷媒的比熱 焓，成爲點Ε〜點Η的任一個的點Η’ 。點Η’〜點G的 熱量成爲依據空調負荷的蒸發熱量，亦即成爲由蒸發器 26與空氣（回風RA)進行熱交換的熱量。 18 - 201226813 因此，配合空間12的空調負荷狀態，在熱氣體旁通 管量0 %〜1 0 0 %的範圍進行控制的方式，可在圖所示的點 E至點Η之間，調整配合空調負荷的熱交換量。 流到該熱氣體旁通管迴路40的熱氣體旁通管量’是 以冷凍循環25的冷媒的循環量爲1〇〇%時，能夠將在壓縮 機的產生熱量予以散熱的量’即使最大流到70%左右，冷 凍循環25也可穩定進行運轉。因此’可適當進行在比例 控制閥5 5的流量控制，且相對於設定溫度（例如2 3 °C ) 可精密溫度控制在±0.0 1°C〜±〇-l°C。 以上雖說明了本發明的實施的形態’可是本發明並不 限於上述的實施的形態，可有各種的變更。亦即，雖以溫 度式膨脹閥作爲膨脹閥進行說明，可是也可以電動式膨脹 閥進行，而在圖3，雖表示使用R407作爲冷媒時的冷媒 凝結壓力、蒸發壓力、壓縮機吸入壓力的一個例子，可是 當然也可依據空調負荷、處理風量等’變更壓縮機的壓縮 能力、凝結壓力、蒸發壓力等。 【圖式簡單說明】 [圖1 ]表示本發明的一實施的形態的整體圖。 [圖2]爲圖1所是的精密空調機的冷凍循環的詳細 圖。 [圖3]是在莫理爾線圖上表示圖2的冷凍循環的說明 圖。 -19· 201226813 【主要元件符號說明】 1 〇 :無塵室 1 2 :空間 1 4 :殼體 2 5 :冷凍循環 26 :蒸發器 2 8 :熱回收部 29 :壓縮機 3 1 :冷凝器 32:散熱能力可變風扇 3 3 :散熱部 40:熱氣體旁通管迴路 -20 -[Brief Description of the Invention] [Technical Field] The present invention relates to a precision air conditioner that circulates air that has been precisely tempered as a space for an air-conditioning object such as an exposure device that is housed in a clean room. [Prior Art] In the surrounding environment of the exposure apparatus of the liquid crystal glass substrate, since the glass substrate thermally expands due to temperature changes, it is necessary to precisely control the temperature of the air conditioner (accuracy ± 0.01 ± ± 0.1 ° C). Such an exposure device or the like is provided in a space formed by a partition wall or the like in a clean room, and a precision air conditioner different from an air conditioner for a clean room is provided on the floor of the clean room, and the precision air conditioner is provided. The air-conditioning air whose cycle is controlled by the precise temperature is supplied to the space to be air-conditioned. The precision air conditioner is composed of a refrigerating cycle in which the air from the space is cooled by the evaporator to a temperature lower than a set temperature (for example, 17 ° C), and then heated to a set temperature by a reheating electric heater (for example, 23) °C) 'And this is circulated into the space as air conditioning air supply. Here, the heat absorbing portion of the evaporator as the refrigeration cycle is provided in the clean room for the air-conditioned space, but the condenser as the heat radiating portion is provided as an outdoor unit in the dust-free outdoor together with the compressor, and is a refrigerant. The piping is connected to the heat radiating unit and the outdoor unit to form an air-cooled air conditioner. Or the proposal: When the condenser that is the heat sink is used as the water-cooled floor in the clean room, the cooling water supply device is installed in the clean room, and the water-cooled pipe is connected to the water-cooled pipe. Various types such as air conditioners (Patent Document 1). However, the precise temperature control in which the air-conditioning air cooled by the evaporator to a temperature lower than the set temperature is heated to a set temperature by the reheating electric heater has a problem that the operating cost of the electric heater increases. Here, in addition to the method proposed in Patent Document 2, the hot gas in the refrigeration cycle is used to flow this to the evaporator, and the hot gas bypass pipe (byPaSS) for controlling the evaporation temperature is also proposed to have air in the evaporator. Further, a reheating condenser is provided on the blowing side to allow hot gas to flow to the reheating condenser, and the reheating condenser is used to heat the air cooled by the evaporator, and then the reheating electric heater is used for precise temperature control. In Patent Document 2, since the hot gas is supplied to the evaporator to control the evaporation temperature, and the air-conditioning air is controlled by the reheating condenser temperature, the operating cost of the reheating electric heater can be reduced to a certain extent, but It is impossible to respond to the hot gas bypass pipe and to precisely control the condensation temperature or evaporation temperature of the refrigeration cycle, so the setting of the reheating electric heater is indispensable. On the other hand, in Patent Document 3, it is proposed to provide a reheating condenser on the blowing side of the evaporator, and to control the bypass amount of the hot gas of the hot gas by the three-way proportional control valve operated by the air pressure, so that reheating can be realized. The condenser's responsive temperature control is used, whereby there is no need to reheat the heater. According to Patent Document 3, the air from the space is cooled by the evaporator to a temperature lower than the set temperature by 5 ° C, and then heated to a set temperature by the reheating condenser. Since the reheating of the electric heater is not required, It can suppress the running cost of -6 - 201226813. [Patent Document 1] [Patent Document 1] Japanese Laid-Open Patent Publication No. 2000-283500 (Patent Document 2) Japanese Laid-Open Patent Publication No. 2009-2 No. 6332 (Patent Document 3) Japanese Patent No. 3 28 3 OBJECT OF THE INVENTION [Problems to be Solved by the Invention] However, in Patent Documents 1 to 3, cooling water is used in the condenser for exhaust heat recovery, and a cooling water supply device is additionally provided in the clean room, and must be carried out. The operation of the cooling water supply device and the heat radiating portion on the condenser side is connected by a cold water pipe. In particular, the recent clean room has become larger and larger, and the height of the clean area of the manufacturing machine such as the exposure device is nearly 10 μm, and the height of the floor return chamber is also about 5 to 6 m, and the number of extended floor areas is also Ten thousand meters, formed in the clean area, is provided with a space covering a large number of process machines. The heat radiating portions that dissipate the heat of the respective spaces are provided in the return chamber, and the cooling water supply device is provided in the clean room, so that the cold water piping connecting the cold water supply device and the heat radiating portions is inevitably long. In addition, the connection must also be carried out at a high level, and it is necessary to have great labor for the heat preservation and water leakage measures of the cold water piping. Further, in Patent Documents 1 to 3, the load of the refrigeration cycle is set to correspond to the maximum air-conditioning load, and since the refrigerant discharge pressure of the compressor is 201226813, the refrigerant heat is absorbed by the evaporator. The heat 'control of the circulation amount of the cooling water flowing to the condenser' can achieve the matching of the heat absorption amount and the heat removal amount. However, when the air-conditioning load is large, the water-cooling type of the condenser can be appropriately controlled. When the air-conditioning load is low, the flow of cooling water supplied to the condenser side is extremely low. It is difficult to stabilize the operation below the control range of the cooling water flow rate. In other words, when the temperature difference between the intake air and the blow-out temperature is ± 2 ° C or less, the air-conditioning load is small. On the other hand, the cooling water temperature supplied to the condenser 'is a cooling water of about 18 ° C. Since the cooling water temperature is lower than the condensation temperature of the refrigerant (before and after 7 ° C), the smaller the air conditioning load is, the amount of cooling water. The more difficult the control becomes, and the refrigeration cycle is stably operated, and the air conditioning load is adjusted to make it difficult to adjust the heat removal amount on the condenser side. In view of the above, an object of the present invention is to provide a precision air conditioner that can control the amount of heat generation while maintaining the load of the refrigeration cycle while maintaining the load of the refrigeration cycle. [Means for Solving the Problem] In order to achieve the above object, the present invention is directed to a precision air conditioner that is introduced into a space of an air-conditioning object to be installed in a clean room and is formed at a set temperature to be circulated in the space. The present invention is characterized by comprising: a refrigerating cycle having a flow of hot gas from the discharge side to the suction side of the compressor, connecting the condenser, the expansion valve, and the evaporator ' in accordance with the 201226813 sequence and discharging the compressor a hot gas bypass pipe loop to the evaporator; a heat recovery unit that receives the air from the space in the evaporator of the refrigeration cycle, and circulates in the space by the evaporator air conditioner at a set temperature; and a heat dissipation unit The condenser is provided in the clean room, and the condenser of the refrigeration cycle is accommodated, and the condenser is provided by air in the clean room, and the condensation pressure of the condenser is kept constant. fan. In the invention, the refrigeration cycle, the heat recovery unit, and the heat radiating portion are housed in the same casing. In the present invention, the hot gas bypass pipe circuit includes a proportional control valve, and the heat recovery unit is provided with a temperature sensor that detects the temperature of the air-conditioned air cooled by the evaporator, and the temperature sensor is inspected. At the outset, the aforementioned proportional control valve is controlled, whereby the air-conditioned air cooled by the evaporator can be precisely controlled. In the present invention, a refrigerant pressure pipe that connects the refrigerant outlet of the evaporator and the suction side of the compressor is connected to a suction pressure regulating valve that maintains a refrigerant suction pressure of the compressor, and the expansion valve is composed of a temperature expansion valve. The piping on the upstream side of the suction pressure adjusting valve is provided with a temperature sensing cylinder of the temperature expansion valve, whereby the refrigerant evaporation pressure in the evaporator can be kept constant. In the present invention, a high-pressure sensor is provided in the high-pressure side refrigerant pipe of the condenser to the temperature-type expansion valve, and a variable-speed device is used to drive the heat-dissipating variable fan of the heat-dissipating portion. The inverter device controls the rotation of the heat-dissipating variable fan so that the condensation pressure of the refrigerant detected by the high-pressure sensor is constant, whereby the refrigerant condensation pressure in the condenser can be kept constant. The high-pressure side refrigerant pipe between the condenser and the high-pressure sensor may be connected to the liquid receiving tank. The casing ??? in which the heat recovery portion and the heat radiating portion are housed may be provided in the return chamber of the clean room. [Effect of the Invention] According to the present invention, when the air in the space of the air-conditioning object is precisely temperature-controlled, the evaporator of the air in the air-conditioned space flows into the hot gas, whereby the air-conditioning air is controlled by the precise temperature, and the heat-dissipating portion provided in the clean room is provided. The air-cooling of the condenser is equivalent to the heat recovered by the heat of the evaporator, thereby performing heat removal, and the precise temperature control can be stably performed, and the excellent effect such as the outdoor unit and the cold water source can be provided in the clean room without dust. [Embodiment] [Embodiment for Carrying Out the Invention] Hereinafter, the performance of a suitable embodiment of the present invention will be described in detail based on the drawings. First, a clean room 10 for a clean room 10; and a manufacturing machine 11 for covering an exposure device or the like provided in the clean room 10, and a precision air conditioner 13 as a space 12 of the air-conditioning object will be described with reference to Fig. 1 . -10- 201226813 The clean room 10 is composed of a process machine provided with an exposure device or the like and provided with a clean area 16 covering the space 12; it is formed above the ceiling 17 of the 16 to supply a clean air space to the clean area 16. 1 8 ; and a return chamber 20 of air from the clean area 16 formed under the ground 1 9 of the clean area 16 . The return chamber 20 and the space 18 are connected by a circulation path 21, and the air passage unit 22 is provided in the circulation path 21, and the ceiling 17 in the air supply space 18 is provided with a plurality of clear areas 16 for blowing clean air and having a wind of HEPA and a fan. Unit 23. The air from the return chamber 20 is introduced into the air conditioner 22 via the circulation path, and the air conditioner 22 is air-conditioned to a set temperature, and the air is purged from the air supply space 18 through the high-level device in the fan filter unit 23, and the air flow is blown downward. Go to the clean area 16. In the clean area 16, there is a space for covering the process machine on the ground 19, and the ambient environment of the air conditioner 110 and the process machine 11 in the space 1 2 in the space of the precision air conditioner is in the present invention. The precision air conditioner 13 is disposed in a dust-free interior, particularly in the return chamber 20. That is to say, the precise air is composed of the air in the space 12 as the return air (RA), and the air conditioner is precisely air-conditioned, and the heat of the evaporator 26 and the circulation fan 27 that supplies the space 1 to the space 1 as the air supply SA is circulated. The collection unit 29 includes a machine unit 30 such as a compressor 29 and a heat dissipation unit 3 3 including a heat dissipation variable fan 3 2 for cooling the condenser 3 . The heat radiating portion 33 is provided at least in the clean room 10, particularly in the room 20. Further, as shown in the figure, the heat recovery unit 28 and the compressor 1 1 are provided with air supply in the clean area, and the air supply dust chamber is sucked by the pair of clean fan filters 21 by the air conditioner empty energy filter 1 1 10 The same machine 13 is guided to perform 28; the machine unit 30 having the first and the ventilator, and the heat dissipating portion 33 is housed in a casing 14 as the precision air conditioner 13. The precision air conditioner 13 is provided in the clean area 16 and the return chamber 20 in the clean room 1 ,, but may be provided in the return chamber 20 in particular. Next, the refrigeration cycle constituting the precision air conditioner 13 will be described based on Fig. 2 . 25. The refrigerating cycle 25 is a condenser 31 that sequentially connects the heat dissipating portion 33 from the discharge side of the compressor 29 to the suction side, a liquid receiving tank 34, a temperature type expansion valve 35 as an expansion valve, and heat recovery. Further, the evaporator 26 and the separator 36 of the unit 28 are mainly configured to be provided with a high-pressure side refrigerant pipe 37a that is branched from the discharge side of the compressor 29 to the condenser 31, and the hot gas is bypassed by the hot gas to the evaporator 26. Tube circuit 40. This refrigeration cycle 25 will be described in further detail. The high pressure side refrigerant pipe 37a on the discharge side of the compressor 29 is provided with a pressure switch 41 for detecting the overload of the compressor 29, and the high pressure side refrigerant pipe 37a is connected to the inlet side of the condenser 31. A condensation pressure regulating valve 50 is connected to the high pressure side refrigerant pipe 37a on the inlet side of the condenser 31. The condenser 31 is formed of a fin & tube, and a condenser 41 is provided with a heat dissipating variable fan 32 in the condenser 31 to form a heat radiating portion 33. The high-pressure side refrigerant pipe 37a on the outlet side of the condenser 3 1 is connected to the upper portion of the liquid receiving tank 34, and a high-pressure side refrigerant pipe 37b is connected to the bottom of the liquid receiving tank 34. A high-pressure sensor 42 is connected to the high-pressure side refrigerant pipe 37b from the liquid receiving tank 34 to the temperature expansion valve 35, and a high-temperature side refrigerant pipe 37b' downstream thereof is connected to a glass level meter that detects the amount of water. 43. Filtration for removing moisture in the refrigerant -12- 201226813 Dryer 44, a sputum-free valve (PacklESS valvE) as a check valve 45 ° Low-pressure side refrigerant pipe 37c from the temperature type expansion valve 35, connected to the evaporator 26 The entrance side. The evaporator 26 is formed of a fin & tube, and a heat recovery portion 28 provided with a circulation fan 27 is formed at the outlet side of the evaporator 26. The pressure gauge 46, the external pressure equalization introduction valve 47, the filter 48, and the suction pressure regulating valve 49 are sequentially connected from the outlet side of the evaporator 26 to the low pressure side refrigerant piping 37c of the separator 36. The temperature type expansion valve 35 is composed of a diaphragm valve. Although not shown in detail, one of the diaphragm chambers may be connected to the temperature sensing tube 52 via the capillary 51, and the other diaphragm chamber may be connected to the outer tube 53. The temperature sensing cylinder 52 is provided along the low pressure side refrigerant pipe 3 7 c on the outlet side of the evaporator 26, and the outer equalizing pipe 5 3 is connected to the external pressure equalizing introduction valve 47. The temperature type expansion valve 35 is a pressure acting on the diaphragm from the temperature sensing cylinder 52 via the capillary 51, (pressure according to the evaporation temperature of the evaporator 26), and acting on the other side of the diaphragm from the outer tube 53. The differential pressure of the pressure (evaporation pressure of the evaporator 26) controls the valve opening degree (decompression degree). Further, in the illustrated example, an example of the externally-balanced temperature type expansion valve 35 will be described. However, an internal balance type temperature expansion valve or an electric expansion valve may be used. The suction pressure adjusting valve 49 receives the refrigerant pressure on the downstream side, and adjusts the suction pressure of the compressor 29 so that the refrigerant pressure becomes constant. The hot gas bypass pipe circuit 4 is connected by a bypass pipe connecting the pipe from the discharge 13-201226813 side of the compressor 29 to the high-pressure side refrigerant pipe 3 "7a of the condenser 3 and the evaporator 26; It consists of a proportional control valve that connects the piping of its bypass pipe. Further, a filter 56 is connected to the bypass pipe of the upstream side of the proportional control valve 55. The heat recovery unit 28 is provided with a temperature detector 58 that detects the temperature of the air supply SA that is air-conditioned by the evaporator 26 and is supplied to the space 12 by the circulation fan 27, and the detection 値' of the temperature sensor 58 is formed. The proportional control valve 55 of the hot body bypass pipe circuit 40 is controlled. Further, the heat-dissipating variable variable fan 32' of the heat radiating portion 33 is driven to be changeably changed by the number of revolutions 60, and the detecting device of the high-sensing device 42 is input to the inverter device 60, and the heat-dissipating capability is controlled by the inverter device 60. The manner in which the air volume of the fan 32 can be made makes the detection 値 of the high voltage sensor 42 constant. In the refrigeration cycle 25 of Fig. 2, the cold gas (hot gas) compressed by the compressor 29 is pressurized by the condensation pressure regulating valve 50, mainly through the condenser 31, and here, the variable fan is used. The rotation of 32 is condensed by heat exchange (23 to 25 ° C right) in the air returning recirculation chamber 20, and is decompressed to the evaporator 26 at the temperature type expansion valve 35. On the other hand, a part of the hot gas from the compressor 29 is flow-regulated from the hot gas bypass pipe circuit 4 at the proportional control valve 55, and is mixed with the gas-liquid mixed phase refrigerant decompressed in the temperature type expansion valve 35. First class to evaporator 26. In the heat recovery portion 28, the return RA' from the space 12 is introduced to cool this by the evaporator 26 to form a set temperature of ±0.01 to ±(°C, and is supplied to the space 1 as a precise temperature controlled supply air SA. P 55 54 The sensible gas-filled pressure-variable medium-controlled wind-controlled left-flow part control wind is 1.1 - 14 - 201226813 The refrigerant recovered by the heat recovery of the evaporator 26 is adjusted as the evaporation refrigerant at the suction pressure regulating valve 49 to the suction pressure of the compressor 29, and is separated. 36 is sucked into the winter compressor 29 and is again compressed as hot gas to be circulated. First, in the present invention, the compressor 29 is adjusted to a suction pressure by a suction pressure regulating valve, and superheated (5 t higher than the saturated gas line) The evaporating refrigerant at the temperature is compressed to a predetermined pressure to form a hot gas which is supplied to both sides of the evaporator 26 via the condenser 31 of the heat radiating portion 33 and the hot gas bypass pipe 40. At this time, the high voltage sensor 42 The pressure on the outlet side of the condenser 31 is checked, and according to this, the inverter unit 60 controls the amount of blown air of the heat-dissipating variable variable fan 32, and the condensing pressure regulating valve adjusts the pressure flowing into the condenser 31. Thereby, the condenser 3 is adjusted. The exchange amount (exhaust heat) of 1 and the condensation pressure at the condenser 31 can be kept constant regardless of the variation of the amount of the hot gas bypass pipe. The junction at the condenser 31 is due to the air in the return chamber 20 ( The heat exchange is carried out at a temperature of 23 ° C to 25 ° C. Therefore, the difference between the temperature of the condensing refrigerant and the temperature of the air is small, and even if the amount of heat is small, the amount of heat supplied from the fan 32 can be controlled to control the amount of heat released. The precise temperature control of the supply air SA of the recovery unit 28 is performed by controlling the opening degree of the proportional control valve 55 by the temperature sensor 58 and controlling the amount of hot gas flowing into the evaporator 26 by the hot gas bypass pipe circuit 40. The temperature sensor 58 shows an example of detecting the temperature of the air supply SA on the outlet side of the radiator 26 of the heat recovery unit 28, but the return air on the inlet side of the evaporator 26 may be additionally provided. The temperature of the RA is warmed up by the warmer 49. The heat is condensed into the heat. The steam is further -15-201226813. The sensor is controlled by the temperature sensor of its inlet and outlet. 55 〇 On the other hand, the temperature Expansion valve 35 regardless of hot gas bypass The amount of pressure reduction adjusts the degree of pressure reduction, and the evaporation pressure of the evaporator 26 is kept constant. That is, the temperature of the outlet side of the evaporator 26 is converted into the pressure of the refrigerant enclosed in the temperature sensing cylinder 52, and this is introduced into the temperature type via the capillary 51. One of the diaphragm chambers of the expansion 35 simultaneously introduces the evaporation pressure of the refrigerant evaporated in the evaporator into the other side of the diaphragm of the temperature expansion valve 35 via the outer equalization tube 53, and adjusts the temperature type expansion valve with the differential pressure of the two diaphragm chambers. 35. The degree of pressure reduction. Thereby, in the evaporator 26, the evaporation pressure is kept constant, and the amount of refrigerant evaporation in the generator 26, that is, the amount of heat exchange between the return air RA and the refrigerant by the amount of hot gas inflow, Therefore, precise temperature control of the air conditioning load can be performed. In the refrigeration cycle 25, the heat recovered in the evaporator 26 of the heat recovery unit 28 by the condenser 31 of the heat radiating portion 33 dissipates heat to the air in the return chamber, but the heat is discharged as compared with the clean room. The heat of the 1〇 adjustment 1 3 is very small, so the air conditioner 1 3 can be fully processed. Therefore, it is not necessary to install the external unit, the cold water supply device, and the like for the purpose of heat removal in the clean room 1 and to connect the refrigerant tubes. Further, at the time of the precise temperature control, the hot gas bypass pipe circuit 40 controls the flow rate of the hot gas to the evaporator 26 by the air conditioning load of the return flow chamber 20 with the proportional control valve 55. At this time, the condenser 31 controls the condensing pressure of the venting pressure of the high-pressure sensing valve and the inner chamber of the valve 26 to control the venting pressure of the air-conditioning chamber, and the temperature-type expansion valve 35 The evaporation pressure is controlled to be constant, and the suction pressure adjustment valve 49 adjusts the suction pressure of the compressor 29 so that the refrigeration cycle 25 can be stably operated. Further, the proportional control valve 55 controls the amount of hot gas in accordance with the change in the air-conditioning load of the return chamber 20, and the refrigerant 26 performs heat recovery in accordance with the air-conditioning load. Thereafter, the hot gas compressed by the compressor 29 is introduced into the condenser 31 of the heat radiating portion 33 to dissipate heat. In this way, the heat is dissipated after the heat recovery. Therefore, when the air-conditioning load is rapidly changed, the heat recovery amount in the refrigeration cycle 25 and the heat radiation amount are likely to be deteriorated. However, since the liquid receiving tank 34 is provided in the refrigeration cycle 25, Therefore, the refrigeration cycle 25 can be stably operated. Next, the refrigeration cycle 25 will be described on the Morris diagram of FIG. Figure 3 shows the refrigeration cycle on the Moore diagram when R407C is used in the refrigerant, and is a saturated gas line indicating that the horizontal axis is specific heat (kJ/kg), the vertical axis is absolute pressure (MPa), and Lg is R4 07C. L1 is a saturated liquid line. First, the refrigerant sucked into the compressor 29 is introduced into the compressor 29 by the suction pressure adjusting valve 49 at a point A (12 ° C, 0.5 MPa). This point A is in a superheated state on the gas phase side which is sufficiently higher (+ 5 °C) than the saturated gas line Lg. The refrigerant gas is compressed by the compressor 29 to the point B (75 ° C, 2.0 MPa). The hot gas at the point B is supplied to the side of the condenser 31 and the side of the hot gas bypass pipe 40, and at the point of divergence, the pressure drops to the point C (1.7 MP a). The hot gas introduced into the condenser 31 is cooled by the heat-dissipating pressure at the point C to pass through the saturated liquid line L1, and is cooled from the gas-liquid mixed phase state of -17 to 201226813 to the point D which becomes the supercooled liquid (3 1 °C). The degree of subcooling at point D can be controlled by the temperature expansion valve 35. The temperature expansion valve 35 is pressed to point E (1 1 ° C, 0.8 MPO. At the evaporator 26, the pressure at the point E can be maintained. Evaporation pressure. On the other hand, the hot gas from point C is introduced into the evaporator 26' and the pressure drops to point F (0.8 MPa), which becomes the evaporation pressure of the evaporator 26. At the evaporator 26, the hot gas flowing into the point F is The refrigerant that has been decompressed to the point E by the temperature expansion valve 35 exchanges heat with the air (return air RA) from the space 12. Thereby, the refrigerant becomes the state of the point G 'from the outlet of the evaporator 26 The inlet side of the suction pressure adjusting valve 49 is sucked into the pressure regulating valve 49, and is pressure-reduced from the point G to the point A, and is introduced to the compressor 29. The freezing cycle on the Morris chart, point C to point The heat of D is the heat dissipation amount of the condenser 31, the heat of the point E to the point G is the heat amount of the evaporator 26, and the heat radiation amount of the condenser 31 is the heat of the compressor 29 (the heat of the point G to the point F) and The total amount of heat of evaporation heat. Here, when the amount of hot gas bypass pipe is 〇%, the heat of evaporation of the evaporator 26 When the amount of heat from the point E to the point G is no air-conditioning load and the amount of the hot gas bypass pipe is 100%, the heat of the compressor 29 is dissipated by the condenser 26, and the specific heat of the refrigerant at the inlet of the evaporator 26 is The heat of the compressor 29 is subtracted from the point G to become a point Η. Therefore, the amount of heat of the refrigerant at the inlet of the evaporator 26 is Ε% to 00% with respect to the amount of the hot gas bypass pipe, and becomes a point Ε~Η Any one of the points Η'. The heat of the point 〜 to the point G becomes the heat of evaporation according to the air conditioning load, that is, the heat exchanged by the evaporator 26 and the air (return air RA). 18 - 201226813 Therefore, the space is matched. The air conditioning load state of 12 is controlled in a range of 0% to 10.0% of the hot gas bypass pipe, and the amount of heat exchange with the air conditioning load can be adjusted between points E to Η shown in the figure. The amount of the hot gas bypass pipe flowing to the hot gas bypass pipe circuit 40 is such that the amount of heat generated by the compressor can be dissipated even when the circulation amount of the refrigerant in the refrigeration cycle 25 is 1%. Flow to about 70%, the refrigeration cycle 25 can also run stably Therefore, the flow rate control of the proportional control valve 55 can be appropriately performed, and the precise temperature can be controlled to ±0.0 1 °C to ±〇-l °C with respect to the set temperature (for example, 2 3 °C). The present invention is not limited to the above-described embodiment, and various modifications may be made. However, although the temperature expansion valve is used as the expansion valve, the electric expansion valve may be used. 3 shows an example of the refrigerant condensation pressure, the evaporation pressure, and the compressor suction pressure when R407 is used as the refrigerant. However, it is of course possible to change the compression capacity, the condensation pressure, and the evaporation pressure of the compressor depending on the air conditioning load, the treatment air volume, and the like. Wait. BRIEF DESCRIPTION OF THE DRAWINGS [Fig. 1] An overall view showing an embodiment of the present invention. Fig. 2 is a detailed view of a refrigeration cycle of the precision air conditioner of Fig. 1; Fig. 3 is an explanatory view showing the refrigeration cycle of Fig. 2 on a Morris diagram. -19· 201226813 [Description of main component symbols] 1 〇: clean room 1 2 : space 1 4 : case 2 5 : refrigeration cycle 26 : evaporator 2 8 : heat recovery part 29 : compressor 3 1 : condenser 32 : Heat-dissipating variable fan 3 3 : Heat sink 40: Hot gas bypass pipe loop -20 -