200843898 九、發明說明： 【發明所屬之技術領域】200843898 IX. Description of the invention: [Technical field to which the invention pertains]
本發明係關於一種自動托板交換機（The present invention relates to an automatic pallet switch (
件間供給及收回液壓油，該輛係、_ 該車由係一體形成有一葉片，該止擋件則Supply and recovery of hydraulic oil between the parts, the vehicle, the vehicle is integrally formed with a blade, the stop is
该止擔件之外殼與該軸之上液壓板及下液壓板間供給及收回液壓 油，以藉罐油之壓力而使該軸上下運動，藉此使一托板與該 車由之運動有機地聯鎖。 【先前技術】 利用適當的工具、以各種切削或非切削成形方式加工一金屬或 非金屬材料之機械設備稱為機床。 根據在利用一刀尖或一鑽頭之一加工過程中是否產生碎屑而 定，可將機床劃分成切削機床與金屬成形機床。 切削機床於加工過程中會產生材料碎屑，其包含車床（lathe)、 銑床（milling machine )、加工中心（machining center )、鑽床（drilling machine )、鏜床（boring machine )、磨床（grinding machine )、 切齒床（gear cutting machine )、專用加工機床等等。金屬成形機 床則不於加工過程中產生材料碎屑，其包含機械壓力機 (mechanical press)、氣動壓力機（pneumatic press)、剪板折彎 機(cutting and bending machine)、鍛造機（forging machine)、 拉製機（drawing machine)等等。 200843898 著技術之^展及對生產率要求之提高’已開發出—種自動化 數控切削機床。近來，數控切削機床之開發曾被劃分成車床系列 與銑床系列，然而，其現在被整合於一起，因而出現了 —種多功 月匕加工中〜。由於工業領域中對加工中心之需求甚廣，因而加工 中心之市場迅速擴大。 加工中心係為一種可於一單個機器中執行各種切削加工之機 床，其不僅具有一自動更換刀具之功能，且亦具有一自動加工一 工件之至少二表面之功能。加工中心被區分成用於加工一旋轉工 件之旋轉加卫中心與用於加工—非旋轉工件之非旋轉加工中心。 用於加工非旋轉工件之非旋轉加工中心係從NC銑床或NC鑽床 改良而來，其包含一自動刀具交換機（automatic tool changer ; ATC )、一多刀刀座（t〇〇1 magazine )以及一自動托板交換機 (automatic pallet changer ； APC ) 〇 用於加工旋轉工件之旋轉加工中心則係從NC車床改良而來，用 以於在執行切削加工之後執行例如分度、凹槽加工、孔加工、攻 螺紋等各種加工，其亦包含ATc及APC。 如上所述，當前之趨勢係旋轉加工中心與非旋轉加工中心皆實 質採用APC。 根據其傳動類型而定，APC可劃分成凸輪.軸（eam_shaft)型、 齒條-齒輪（rack-pinion)型 '滾珠_螺桿型及葉片_ 止擋件 (vane-stopper)型 ° 第1圖顯示一習知凸輪-軸型自勤虹 主㈢勒托板交換機（APC)。該凸輪- 軸型APC包含一軸120與一凸輪撫m， 錢構150，軸120係上下運動， 200843898 凸輪機構150則與軸120聯鎖以進行旋轉。 於凸輪-軸型APC中，軸120藉由從一流體壓力或如馬達之一動 力傳遞裝置（power transmitting means )接收動力而上下運動，與 軸120聯鎖之凸輪機構150則被構造成隨轴120之上下運動而旋 轉。然而，因凸輪-軸型APC具有諸多構成元件，故其製造及維護 較為困難，致使製作時間較長且成本升高。 第2圖顯示一習知齒條•齒輪型自動托板交換機（APC )。該齒 條-齒輪型APC包含一齒條160及一齒輪161，齒條160於其一側 上形成一齒部，齒輪161則具有與齒條160之齒部相嚙合之一齒 部。 因齒條-齒輪型APC被構造成藉由一動力傳遞裝置使齒條160 上下運動，並藉由齒條160之上下運動而帶動齒輪161旋轉，故 其結構複雜，因而難以製造。再者，因採用簡易之齒嚙合型動力 傳遞方法，故難以準確、穩定地傳遞動力。 第3圖顯示一習知滾珠-螺桿型APC。該滾珠-螺桿型APC包含 一中心軸以及一滾珠170，其中中心轴上形成一螺旋型滾道171。 在滾珠-螺桿型APC中，一活塞被固定至一外殼，以包圍該中心 軸，該活塞係藉由一流體壓力而上下運動，且活塞之上下運動亦 使設置於該活塞中之滾珠170沿中心軸之螺旋型滾道171上下運 動，藉以帶動中心軸旋轉。然而，滾珠-螺桿型APC結構複雜，因 而難以製造。再者，在自上下運動轉換成旋轉運動之能量轉換過 程中會出現能量損失，且滾珠170與螺旋型滾道171間之摩擦會 降低其耐用性。 200843898 此外，其利用一流體作為一動力傳遞媒介，因而若於一流體供 給及收回過程中不能迅速供給及收回流體，即會產生一排斥力。 此外，若流體供給及收回過快，亦會因元件間之衝突而產生排斥 力0 【發明内容】 本發明之一目的在於提供一種自動托板交換機（automatic pallet changer; APC)，其中利用一葉片及一止擋件來簡化APC之結構， 從而容易製造及易於維護該APC。 本發明之另一目的在於提供一種自動托板交換機，其中於一流 體供給及收回過程中適當地控制一流體之一流率。 為達成本發明之上述目的，提供一種自動托板交換機（APC)， 包含：一可旋轉之圓柱形中空軸；一上部液壓板及一下部液壓板， 分別設置於該軸之上側及下側且與該軸形成一體；一葉片，設置 於該上部液壓板與該下部液壓板間，以包圍該軸之一外表面之一 部分，且與該軸形成一體；一止擋件，設置於該軸之該外表面上， 以限制該轴旋轉；一外殼，用以容納該轴及該止擋件，且其中具 有一液壓供給口； 一固定臂，耦接至該外殼，以固定該止擋件； 以及一托板，與該軸聯鎖，以上、下、左、右地運動。 較佳地，一液壓油流動部形成於該葉片之一側、及沿一圓周方 向與該葉片之該一側相隔一所期望角度之另一側。 較佳地，該液壓油流動部包含一第一流動部以及一第二流動 部，該第一流動部係形成一矩形堰形狀，其一深度自該葉片之一 側或另一側朝該葉片之一圓周方向逐漸變淺，而該第二流動部係 9 200843898 形成一三角形堰形狀，其一深度及一寬度自該葉片之一側或另一 側朝該葉片之該圓周方向逐漸變淺及變窄，藉以供給及收回液壓 油，並且吸收一震動。 較佳地，該止擋件係設置於該上部液壓板與該下部液壓板間， 以由該固定臂限制其左右旋轉運動。 較佳地，一用以在其中插入該固定臂之縱向伸長橢圓形固定部 形成於該止擋件之該外表面中，以由該固定臂固定該止擋件。 【實施方式】 在以下實例及對照實例中將例示本發明之可行且當前較佳之實 施例。 第4圖係為根據本發明之一自動托板交換機（APC)之一立體 分解圖，第5圖係為一軸之一立體圖，第6(a)圖及第6(b)圖係 為根據本發明之自動托板交換機（APC )之一剖面圖及一端視圖， 第7圖係為顯示軸之旋轉運動之一實例之示意圖，第8圖則係為 顯示轴之上下運動之一實例之示意圖。 參見第4圖及第5圖，該APC包含··一可旋轉之圓柱形中空轴 20 ; —上部液壓板23及一下部液壓板24，分別設置於軸20之上 側及下側且與軸20形成一體；一葉片21，設置於上部液壓板23 與下部液壓板24間，以包圍軸20之一外表面之一部分’且與軸 20形成一體；一止擋件30，設置於轴20之該外表面上，並與葉 片21之一側或另一侧相接觸，以限制轴20旋轉；一外殼10，用 以容置軸20及止擋件30 ; —固定臂11，耦接至外殼10，以固定 止擋件30 ;以及一托板40，與軸20聯鎖，以上、下、左、右地 200843898 運動。 上部液壓板23與下部液壓板24係分別設置於軸20之上側及下 側，並與轴20形成一體，且形成為與外殼10之一内圓周面相接 觸。 葉片21係設置於上部液壓板23與下部液壓板24間，以包圍軸 20之一外表面之一部分，且與軸20形成一體，葉片21具有一所 期望之形狀，以包圍軸20之該外表面之一部分，並被固定成與上 部液壓板23之一下表面、及下部液壓板24之一上表面相接觸。 由此，葉片21與上部液壓板23與下部液壓板24以及軸20相聯 鎖。 於葉片21之一側及另一側上，形成一液壓油流動部22,用作動 力傳遞媒介之液壓油從中流過，以傳遞動力給軸20。 液壓油流動部22包含一第一流動部22a以及一第二流動部 22b，第一流動部22a係形成一矩形堰形狀，其一深度自葉片21 之一側或另一側朝葉片21之一圓周方向逐漸變淺，而第二流動部 22b係形成一三角形堰形狀，其一深度及一寬度自葉片21之一側 或另一側朝葉片21之該圓周方向逐漸變淺及變窄，藉以供給及收 回液壓油，並且吸收一震動。 當將液壓油於外殼10之一液壓油口 12供給及回收時，液壓油 會流過第一流動部22a及第二流動部22b。液壓油流過第一流動部 22a及第二流動部22b之量及流速相依於各該第一流動部22a及第 二流動部22b之尺寸及形狀。 倘若流過第一流動部22a及第二流動部22b之液壓油量增大， 200843898 則軸20之一旋轉速度亦將增大。然而，止擋件30與葉片21間會 發生碰撞，進而產生一排斥力。 相反地，倘若流過第一流動部22a及第二流動部22b之液壓油 量減少，則軸20之旋轉速度降低，且收回充注於止擋件30與葉 片21間之液壓油之過程被延遲，進而產生一排斥力。 因此，第一流動部22a及第二流動部22b分別形成矩形堰形狀 及三角形堰形狀，該矩形堰形狀之深度自葉片21之一側或另一側 朝葉片21之圓周方向逐漸變淺，該三角形堰形狀之深度及寬度自 葉片21之一側或另一側朝葉片21之該圓周方向逐漸變淺，藉以 正確限制液壓油之量及流速，以有效控制軸20之旋轉。 止擋件30係與軸20 —同容納於外殼10中以限制軸20之旋轉， 其夾置於上部液壓板23與下部液壓板24間，並藉由一耦接至外 殼10之固定臂11而固定至外殼10。 此處，一用以在其中插入固定臂11之縱向伸長橢圓形固定部31 形成於止擋件30之該外表面中，以由固定臂11固定止擋件30。 由於固定部31係形成為縱向伸長之橢圓狀，故止擋件30之左 右旋轉運動受到固定臂11限制，但可容許於固定部31與固定臂 11間之一距離範圍内進行上下運動。 參見第6(a)圖、第6(b)圖、第7圖及第8圖，若從形成於外殼 10中之液壓油口 12向止擋件30與葉片21之一側間供給液壓油， 並經由該外殼之另一液壓油口 12收回充注於止擋件30與葉片21 另一側間之液壓油，便可使轴20旋轉。 而且，若向止擋件30與葉片21另一側間供給液壓油，並收回 12 200843898 充注於止擋件30與葉片一側間之液壓油，便可使軸20反向旋轉。 用於供給及收回止擋件30與葉片21之一側或另一側間之液壓 油之液壓油口 12，係於外殼10中對應於形成於葉片21之一側及 另一側中之第一流動部22a及第二流動部22b而形成。 液壓油亦供給至上部液壓板23之一上側與下部液壓板24之一 下側以及自此收回，進而產生一壓力並藉由該壓力使軸20上下運 動。此時，軸20在形成於止擋件30外表面中之固定部31與固定 臂11間之距離範圍内上下運動，其中固定臂11係耦接至外殼10 以固定止擋件30。 與葉片21、軸20、止擋件30及外殼10相接觸之接觸面係分別 與其相間隔一 0.05毫米之間隙，藉以防止在供給及收回液壓油之 過程中液壓油出現浪漏。因此，無需利用一單獨之密封部件即可 w止液壓油:¾漏。 ' 此外，由於與葉片21、轴20、止擋件30及外殼10相接觸之接 觸面係分別相間隔一 0.05毫米之間隙，故液壓油會形成一油膜， 該油膜具有潤滑油之功效。 產業利用性 根據本發明，藉由利用葉片與止擋件，可簡化APC之結構，進 而使其容易製造及維護。 此外，因可正確控制經由液壓油流動部所供給及收回之液壓油 量，故軸之旋轉速度得到提高且排斥力得到降低，進而改善APC 之效能。 此外，根據本發明，無需利用額外之裝置便可使轴進行旋轉運 13 200843898 動及上/下運動。 此外，因各該部件皆係藉由一精密之加工製程而製成，故可防 止液壓油透過該等部件間之接觸面發生洩漏，因而無需提供一額 外密封部件，而且因液壓油會形成一潤滑膜，故無需利用單獨之 潤滑油即可自然地達成潤滑作用。 熟習此項技藝者將可理解，可輕易地根據上文說明所揭露之概 念及具體實施例而修改或設計出其他用於達成本發明相同目的之 實施例。熟習此項技藝者亦將可理解，此等等效之實施例並不背 離在隨附申請專利範圍中所述之本發明之精神及範圍。 【圖式簡單說明】 第1圖係為一習知凸輪-軸型自動托板交換機（APC)之示意圖； 第2圖係為一習知齒條-齒輪型自動托板交換機（APC)之示意 圖； 第3圖係為一習知滾珠-轴桿型自動托板交換機（APC)之示意 圖； 第4圖係為根據本發明之一自動托板交換機（APC)之一立體 分解圖； 第5圖係為一軸之一立體圖； 第6(a)圖係為根據本發明之自動托板交換機（APC)之一剖面 圖； 第6(b)圖係為第（6a)圖之一端視圖； 第7圖係為顯示軸之旋轉運動之一實例之示意圖；以及 第8圖係為顯示軸之上下運動之一實例之示意圖。 14 200843898 【主要元件符號說明】 10 :外殼 12 :液壓油口 21 :葉片 22a :第一流動部 23 :上部液壓板 30 :止擋件 40 :托板 150 :凸輪 161 :齒輪 171 :滾道 11 :固定臂 20 :軸 22 :液壓油流動部 22b :第二流動部 24 :下部液壓板 31 :固定部 120 ··軸 160 :齒條 170 :滾珠 t. 15The outer casing of the support member and the hydraulic plate and the lower hydraulic plate above the shaft supply and withdraw hydraulic oil to move the shaft up and down by the pressure of the can oil, thereby making a pallet and the movement of the vehicle organic Ground interlocking. [Prior Art] A mechanical device that processes a metal or non-metal material in various cutting or non-cutting forms using a suitable tool is called a machine tool. The machine can be divided into a cutting machine and a metal forming machine depending on whether or not debris is generated during machining using one of the tips or one of the drills. The cutting machine produces material debris during the machining process, including lathe, milling machine, machining center, drilling machine, boring machine, grinding machine, Gear cutting machine, special processing machine, etc. Metal forming machines do not produce material debris during processing. They include mechanical presses, pneumatic presses, cutting and bending machines, and forging machines. , drawing machine, and so on. 200843898 Technology development and improvement of productivity requirements has been developed - an automated CNC cutting machine. Recently, the development of CNC cutting machine tools has been divided into a series of lathes and milling machines. However, it has now been integrated, and thus there has been a multi-function process. Due to the wide demand for processing centers in the industrial sector, the market for processing centers is rapidly expanding. The machining center is a machine that can perform various cutting operations in a single machine, which not only has the function of automatically changing the tool, but also has a function of automatically machining at least two surfaces of a workpiece. The machining center is divided into a rotary center for machining a rotating workpiece and a non-rotating machining center for machining-non-rotating workpieces. The non-rotating machining center for machining non-rotating workpieces is modified from an NC milling machine or an NC drilling machine, and includes an automatic tool changer (ATC), a multi-tool holder (t〇〇1 magazine), and a Automatic pallet changer (APC) The rotary machining center for machining rotating workpieces is modified from the NC lathe to perform, for example, indexing, groove machining, hole machining, etc. after performing the cutting process. Various processing such as tapping, which also includes ATc and APC. As mentioned above, the current trend is that APC is used both in rotary machining centers and non-rotating machining centers. Depending on the type of transmission, APC can be divided into cam. shaft (eam_shaft) type, rack-pinion type 'ball _ screw type and vane _ stop type (vane-stopper) type. A conventional cam-axis type self-service rainbow main (three) Leto board switch (APC) is shown. The cam-shaft type APC includes a shaft 120 and a cam som, a structure 150, and a shaft 120 up and down. The 200843898 cam mechanism 150 is interlocked with the shaft 120 for rotation. In the cam-shaft type APC, the shaft 120 is moved up and down by receiving power from a fluid pressure or a power transmitting means such as a motor, and the cam mechanism 150 interlocked with the shaft 120 is configured to follow the shaft. 120 moves up and down and rotates. However, since the cam-shaft type APC has many constituent elements, it is difficult to manufacture and maintain, resulting in a long production time and an increased cost. Figure 2 shows a conventional rack and pinion type automatic pallet switch (APC). The rack-and-pinion type APC includes a rack 160 and a gear 161. The rack 160 has a tooth portion formed on one side thereof, and the gear 161 has a tooth portion that meshes with the tooth portion of the rack 160. Since the rack-and-pin type APC is configured to move the rack 160 up and down by a power transmission device and to rotate the gear 161 by the upper and lower movements of the rack 160, the structure is complicated and it is difficult to manufacture. Furthermore, since the simple tooth meshing type power transmission method is employed, it is difficult to transmit power accurately and stably. Figure 3 shows a conventional ball-screw type APC. The ball-screw type APC includes a center shaft and a ball 170, wherein a spiral type raceway 171 is formed on the center shaft. In the ball-screw type APC, a piston is fixed to a casing to surround the center shaft, the piston is moved up and down by a fluid pressure, and the upper and lower movement of the piston also causes the ball 170 disposed in the piston to follow The spiral raceway 171 of the center shaft moves up and down to drive the central shaft to rotate. However, the ball-screw type APC has a complicated structure and is therefore difficult to manufacture. Furthermore, energy loss occurs during the energy conversion from the up-and-down motion to the rotary motion, and the friction between the ball 170 and the spiral race 171 reduces the durability. 200843898 In addition, it utilizes a fluid as a power transmission medium, so that if a fluid cannot be quickly supplied and withdrawn during a fluid supply and recovery process, a repulsive force is generated. In addition, if the fluid supply and recovery are too fast, a repulsive force is generated due to the conflict between the components. [Invention] It is an object of the present invention to provide an automatic pallet changer (APC) in which a blade is utilized. And a stop to simplify the structure of the APC, making it easy to manufacture and easy to maintain the APC. Another object of the present invention is to provide an automatic pallet changer in which a flow rate of a fluid is appropriately controlled during the supply and retraction of the first-class body. In order to achieve the above object of the present invention, an automatic pallet switch (APC) is provided, comprising: a rotatable cylindrical hollow shaft; an upper hydraulic plate and a lower hydraulic plate, respectively disposed on the upper side and the lower side of the shaft and Formed integrally with the shaft; a blade disposed between the upper hydraulic plate and the lower hydraulic plate to surround a portion of an outer surface of the shaft and integral with the shaft; a stop member disposed on the shaft The outer surface is configured to restrict rotation of the shaft; a housing for receiving the shaft and the stopper, and having a hydraulic supply port therein; a fixing arm coupled to the outer casing to fix the stopper; And a pallet, interlocked with the shaft, moving up, down, left, and right. Preferably, a hydraulic oil flow portion is formed on one side of the blade and on the other side of the blade at a desired angle from one side of the blade in a circumferential direction. Preferably, the hydraulic oil flow portion includes a first flow portion and a second flow portion, the first flow portion forming a rectangular shape with a depth from one side of the blade or the other toward the blade One of the circumferential directions gradually becomes shallower, and the second flow portion 9 200843898 forms a triangular shape with a depth and a width gradually becoming shallower from one side or the other side of the blade toward the circumferential direction of the blade and Narrowed to supply and retract hydraulic oil and absorb a shock. Preferably, the stopper is disposed between the upper hydraulic plate and the lower hydraulic plate to restrict the left and right rotational movement thereof by the fixed arm. Preferably, a longitudinally elongated elliptical fixing portion for inserting the fixing arm therein is formed in the outer surface of the stopper to fix the stopper by the fixing arm. [Embodiment] A feasible and presently preferred embodiment of the present invention will be exemplified in the following examples and comparative examples. Figure 4 is an exploded perspective view of an automatic pallet changer (APC) according to the present invention, and Figure 5 is a perspective view of one axis, and Figures 6(a) and 6(b) are based on this A cross-sectional view and an end view of one of the inventions of the automatic pallet changer (APC), FIG. 7 is a schematic diagram showing an example of the rotational movement of the shaft, and FIG. 8 is a schematic diagram showing an example of the upper and lower movement of the shaft. Referring to Figures 4 and 5, the APC comprises a rotatable cylindrical hollow shaft 20; an upper hydraulic plate 23 and a lower hydraulic plate 24, respectively disposed on the upper and lower sides of the shaft 20 and with the shaft 20 Formed integrally; a blade 21 disposed between the upper hydraulic plate 23 and the lower hydraulic plate 24 to surround a portion of one of the outer surfaces of the shaft 20 and integral with the shaft 20; a stop member 30 disposed on the shaft 20 On the outer surface, and in contact with one side or the other side of the blade 21 to restrict the rotation of the shaft 20; a housing 10 for accommodating the shaft 20 and the stopper 30; - the fixing arm 11 coupled to the outer casing 10 , with a fixed stop 30; and a pallet 40, interlocked with the shaft 20, above, down, left, and right 200843898 movement. The upper hydraulic plate 23 and the lower hydraulic plate 24 are respectively disposed on the upper side and the lower side of the shaft 20, and are integrally formed with the shaft 20, and are formed in contact with the inner circumferential surface of one of the outer casings 10. The blade 21 is disposed between the upper hydraulic plate 23 and the lower hydraulic plate 24 to surround a portion of one of the outer surfaces of the shaft 20 and is integral with the shaft 20, the blade 21 having a desired shape to surround the shaft 20 One of the surfaces is fixed to be in contact with a lower surface of the upper hydraulic plate 23 and an upper surface of the lower hydraulic plate 24. Thereby, the blade 21 and the upper hydraulic plate 23 are interlocked with the lower hydraulic plate 24 and the shaft 20. On one side and the other side of the blade 21, a hydraulic oil flow portion 22 is formed through which hydraulic oil serving as a power transmission medium flows to transmit power to the shaft 20. The hydraulic oil flow portion 22 includes a first flow portion 22a and a second flow portion 22b. The first flow portion 22a is formed in a rectangular shape with a depth from one side of the blade 21 or the other side toward the blade 21. The circumferential direction gradually becomes shallower, and the second flow portion 22b forms a triangular shape, and a depth and a width thereof gradually become shallower and narrower from one side or the other side of the blade 21 toward the circumferential direction of the blade 21. Supply and retract hydraulic oil and absorb a shock. When hydraulic oil is supplied and recovered to one of the hydraulic ports 12 of the outer casing 10, the hydraulic oil flows through the first flow portion 22a and the second flow portion 22b. The amount and flow rate of the hydraulic oil flowing through the first flow portion 22a and the second flow portion 22b depend on the size and shape of each of the first flow portion 22a and the second flow portion 22b. If the amount of hydraulic oil flowing through the first flow portion 22a and the second flow portion 22b is increased, the rotational speed of one of the shafts 20 will also increase in 200843898. However, a collision occurs between the stopper 30 and the blade 21, thereby generating a repulsive force. On the contrary, if the amount of hydraulic oil flowing through the first flow portion 22a and the second flow portion 22b is decreased, the rotational speed of the shaft 20 is lowered, and the process of retracting the hydraulic oil charged between the stopper 30 and the blade 21 is Delay, which in turn produces a repulsive force. Therefore, the first flow portion 22a and the second flow portion 22b respectively form a rectangular 堰 shape and a triangular 堰 shape, the depth of the rectangular 堰 shape gradually becoming shallower from one side or the other side of the blade 21 toward the circumferential direction of the blade 21, The depth and width of the triangular 堰 shape gradually become shallower from one side or the other side of the blade 21 toward the circumferential direction of the blade 21, thereby properly limiting the amount and flow rate of the hydraulic oil to effectively control the rotation of the shaft 20. The stopper 30 is housed in the outer casing 10 together with the shaft 20 to restrict the rotation of the shaft 20, and is interposed between the upper hydraulic plate 23 and the lower hydraulic plate 24, and is coupled to the fixed arm 11 of the outer casing 10 by a shaft It is fixed to the outer casing 10. Here, a longitudinally elongated elliptical fixing portion 31 for inserting the fixing arm 11 therein is formed in the outer surface of the stopper 30 to fix the stopper 30 by the fixing arm 11. Since the fixing portion 31 is formed in an elliptical shape elongated in the longitudinal direction, the left-right rotational movement of the stopper 30 is restricted by the fixed arm 11, but it is allowed to move up and down within a distance between the fixed portion 31 and the fixed arm 11. Referring to Figures 6(a), 6(b), 7 and 8, when hydraulic oil is supplied from the hydraulic port 12 formed in the casing 10 to the side of the stopper 30 and the blade 21 And retracting the hydraulic oil filled between the stopper 30 and the other side of the blade 21 via the other hydraulic port 12 of the outer casing, the shaft 20 can be rotated. Further, if hydraulic oil is supplied between the stopper 30 and the other side of the blade 21, and the hydraulic oil filled between the stopper 30 and the blade side is recovered, the shaft 20 can be reversely rotated. The hydraulic oil port 12 for supplying and retracting the hydraulic oil between the stopper 30 and one side or the other side of the blade 21 is corresponding to the one formed on one side and the other side of the blade 21 in the outer casing 10. A flow portion 22a and a second flow portion 22b are formed. The hydraulic oil is also supplied to the lower side of one of the upper and lower hydraulic plates 24 of the upper hydraulic plate 23 and retracted therefrom, thereby generating a pressure and moving the shaft 20 up and down by the pressure. At this time, the shaft 20 moves up and down within a distance between the fixed portion 31 formed in the outer surface of the stopper 30 and the fixed arm 11, wherein the fixed arm 11 is coupled to the outer casing 10 to fix the stopper 30. The contact surfaces in contact with the blade 21, the shaft 20, the stopper 30, and the outer casing 10 are spaced apart by a gap of 0.05 mm, respectively, to prevent leakage of the hydraulic oil during the supply and withdrawal of the hydraulic oil. Therefore, it is not necessary to use a separate sealing member to stop the hydraulic oil: 3⁄4 leak. In addition, since the contact surfaces in contact with the blade 21, the shaft 20, the stopper 30, and the outer casing 10 are spaced apart by a gap of 0.05 mm, respectively, the hydraulic oil forms an oil film which has the effect of lubricating oil. Industrial Applicability According to the present invention, by using a blade and a stopper, the structure of the APC can be simplified, thereby making it easy to manufacture and maintain. In addition, since the amount of hydraulic oil supplied and withdrawn through the hydraulic oil flow portion can be properly controlled, the rotational speed of the shaft is improved and the repulsive force is lowered, thereby improving the performance of the APC. Furthermore, according to the present invention, the shaft can be rotated without using an additional device. In addition, since each of the components is formed by a precise processing process, the hydraulic oil can be prevented from leaking through the contact faces between the components, so that it is not necessary to provide an additional sealing member, and the hydraulic oil forms a The film is lubricated, so lubrication can be achieved naturally without the use of a separate lubricant. It will be appreciated by those skilled in the art that <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; It is also to be understood by those skilled in the art that the invention is not to be construed as limited by the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram of a conventional cam-shaft type automatic pallet switch (APC); Fig. 2 is a schematic diagram of a conventional rack-and-pin type automatic pallet switch (APC) Figure 3 is a schematic view of a conventional ball-shaft type automatic pallet switch (APC); Figure 4 is an exploded perspective view of an automatic pallet switch (APC) according to the present invention; 1(a) is a cross-sectional view of an automatic pallet changer (APC) according to the present invention; and FIG. 6(b) is an end view of the (6a) diagram; The figure is a schematic diagram showing one example of the rotational motion of the shaft; and the eighth figure is a schematic diagram showing an example of the upper and lower motion of the shaft. 14 200843898 [Description of main component symbols] 10: Housing 12: Hydraulic port 21: Blade 22a: First flow portion 23: Upper hydraulic plate 30: Stop member 40: Pallet 150: Cam 161: Gear 171: Raceway 11 : fixed arm 20 : shaft 22 : hydraulic oil flow portion 22 b : second flow portion 24 : lower hydraulic plate 31 : fixed portion 120 · shaft 106 : rack 170 : ball t. 15