200908536 九、發明說明 【發明所屬之技術領域】 本發明係有關線型馬達之原點設定方法，特別是有關 內裝作爲以高速重複定位使用的磁性式線型編碼器的線型 馬達之原點設定方法。 【先前技術】 多數使用線型馬達作爲移動機構和運送機構的驅動源 。使用線型馬達之際，檢查線型馬達之移動部的移動位置 是不可缺的。使用線型編碼器作爲檢查相關之移動位置的 手段。又，亦採用將移動部的直線運動轉換成旋轉運動， 藉由旋轉編碼器來檢查移動位置的手法。利用該等之編碼 器檢查出等間隔刻設的磁性記號或光學性記號，且累計該 已檢查的記號，更內插分配至兩個記號間，檢查出移動部 的移動量。 雖然該等之編碼器能檢查出移動部的移動量，亦即遞 增（incremental search)量，但並不能檢查出絕對位置（ 對某一座標原點的位置）。爲了檢查絕對位置，必須設定 記號的累計和內插信號的累計成爲基準的位置。亦即，必 須確立移動部的原點位置。 以往原點位置的確立方法，是採用在線型馬達之固定 部側之所要的位置設置限制開關，讓移動部從既定方向開 始移動，以限制開關所檢查的位置爲原點，來設定確立設 置在移動部的鎖簧（dog)之手法。 -5- 200908536 對此，也提供一種未使用限制開關和鎖簧等之手段的 線型馬達的原點設定方法（例如參照日本專利文獻1 )。 此爲在線型馬達並列設置線型編碼器，作爲位置檢測器（ position detector)，在已決定線型馬達之移動部的位置， 介設運算子（operator )而定位後，自該位置起以低速使 移動部朝已決定的方向移動，在來自霍爾元件（hall element)之磁信號（magnetic signal)的極性產生設定數 變化的位置’將用以演算現在位置的雙向計數器（ bidirectional counter)歸零，藉此以位置檢測器檢查出位 置之原點的手法。 進而’使用光學式線型編碼器的線型馬達，有鑑於附 著塵埃或有污點的話’檢測感度變弱，耐環境性不足，提 供一種耐環境性強’且低成本，不需要磁性式線型編碼器 之設定（setting )的線型馬達（例如參照日本專利文獻2 )。此爲永久磁鐵兼用線型馬達的磁場與線型編碼器的被 fe查體之fe性標度部（magnetic scale) 所構成，並且設 成永久磁鐵的間距間隔爲磁性標度部的標度間距，強烈對 抗塵埃等’增加耐環境性。 [專利文獻1]日本特開平8_322276號公報 [專利文獻2]日本特開2004-56892號公報 【發明內容】 [發明欲解決之課題] 利用限制開關和鎖簧的原點設定或者以原點的確立方 -6 - 200908536 法’需要限制開關和鎖簧，該等限制開關和鎖簧的位置調 整’必須介設運算子進行。 又’以日本專利文獻1所揭示之原點的確立方法，運 算子利用粗略定位在已決定之位置的記號，首先以附加在 移動構件的記號以及附加在固定支承部的記號的兩個記號 在一個永久磁鐵的寬度內粗略爲一致的方式，利用運算子 實施粗略的定位，然後，實行線型馬達的原點設定/確立 處理。因此，在線型馬達之原點設定時，必須介設運算子 ’且需要利用人力的各種設定（setting )作業，完全無法 實現自動的進行原點設定處理。 另一方面，在日本專利文獻2所記載的線型馬達，不 須要磁性式線型編碼器的設定，該磁性式線型編碼器的標 度頭（scale head)，係爲配置以電角度（electric angle )相位偏移90°的方式所形成的複數個霍爾元件所構成， 利用將由霍爾元件輸出的二相正弦波的類比訊號變換爲位 置資料的位置資訊變換器，來演算可動子的現在位置的構 造。可是，如專利文獻2之第2圖（a)所示的感應電壓 (i n d u c e d v ο 11 a g e )波形及編碼器訊號的波形，係爲只能 在複數個永久磁鐵以既定的一定間隔相鄰且規則的排列配 置之除了磁鐵排列之端部的磁鐵排列之中央部側採用的原 理。因此，只處理編碼器訊號波形，並不能設定、確立用 以確定線型馬達之絕對位置的原點。因而，在專利文獻2 所記載的線型馬達，默認採用設定以用確定絕對位置之位 置資訊變換器的原點之手段或手法爲前提。除此之外’在 200908536 專利文獻2中’有關馬達原點及原點設定’亦未能發現任 何的記述。 本發明係爲有鑑於如上述的事情的發明，本發明之目 的在於提供一種能穩定且輕易的實現用以確定線型馬達之 絕對位置的原點之設定及確立的原點設定方法。 [用以解決課題之手段] 藉由本發明之一形態，提供一種線型馬達之原點設定 方法，係爲在圓筒狀構件的中空部，具有：將複數個永久 磁鐵的同一磁極互相面對面的緊密貼合，直列狀配置所構 成的磁轭、和具有與前述磁鐵列隔著磁性空隙而面對面配 置的電樞線圈的電樞、和配設在前述磁鐵列的端部或中途 ，使前述磁鐵列的磁性特性急遽變化的磁性特性急變部、 和以前述磁鐵列構成磁性標度部，將兩個前述永久磁鐵間 的長度，設定成前述磁性標度部的標度間距，並且互相的 以電角度錯開9 0 ° (相當於標度間距的1 / 4波長）來配置 相位的複數個第1磁性檢測器、和從該第1磁性檢測器以 電角度錯開1 80° (相當於標度間距的1 / 2波長）來配置 相位的第2磁性檢測器之沿著前述電樞的長邊方向所具有 的位置檢查用的磁性式線型編碼器；前述磁軛與前述電樞 的任一方爲固定子，另一方爲可動子，在前述電樞側具備 前述磁性式線型編碼器的標度頭（scale head )，使前述 磁軛與前述電樞相對性的直線移行的線型馬達之原點設定 方法’其特徵爲：使前述可動子沿著原點方向移動，搜尋 -8- 200908536 前述磁鐵列之磁性特性產生急遽變化的磁性特性急變 ;以該磁性特性急變位置爲基礎，來設定用以設定原 原點設定基準位置；從該原點設定基準位置開始使可 以既定的減速來減速，使其停在前述標度頭爲既定値 置；從該停止位置開始使前述可動子的移動方向反轉 尋由前述磁性式線型編碼器所得到的磁性特性的極性 點；在該極性變化點的位置，使前述可動子停止，形 述線型馬達之絕對位置的基準位置。 又’藉由本發明之另一形態’提供一種線型馬達 點設定方法，係爲在圓筒狀構件的中空部，具有：將 個永久磁鐵的同一磁極互相面對面的緊密貼合，直列 置所構成的磁軛、和具有與前述磁鐵列隔著磁性空隙 對面配置的電樞線圈的電樞、和配設在前述磁鐵列的 或中途，使前述磁鐵列的磁性特性急遽變化的磁性特 變部、和以前述磁鐵列構成磁性標度部，將兩個前述 磁鐵間的長度，設定成前述磁性標度部的標度間距， 互相的以電角度錯開90° (相當於標度間距的1 / 4波 來配置相位的複數個第1磁性檢測器、和從該第1磁 測器以電角度錯開1 80° (相當於標度間距的1 / 2波 來配置相位的第2磁性檢測器之沿著前述電樞的長邊 所具有的位置檢查用的磁性式線型編碼器；前述磁軛 述電樞的任一方爲固定子，另一方爲可動子，在前述 側具備前述磁性式線型編碼器的標度頭，使前述磁軛 述電樞相對性的直線移行的線型馬達之原點設定方法 位置 點的 動子 的位 ，捜 變化 ..卜- < 八 成B[J 之原 複數 狀配 而面 端部 性急 永久 並且 長） 性檢 長） 方向 與前 電樞 與前 ，其 -9- 200908536 特徵爲：搜尋前述磁鐵列之磁性特性產生急遽變化的磁性 特性急變位置，判斷前述可動子沿著前述磁性特性急變部 方向通過原點；使前述可動子沿著靠近原點的方向移動’ 依舊使其通過原點；更使前述可動子沿著離開原點的方向 ，僅移動既定距離；使前述可動子沿著原點方向移動，搜 尋前述磁性特性急變位置；以該磁性特性急變位置爲基礎 ，來設定用以設定原點的原點設定基準位置；從該原點設 定基準位置開始使可動子以既定的減速來減速，使其停在 前述標度頭爲既定値的位置；從該停止位置開始使前述可 動子沿著原點方向移動，來搜尋由前述磁性式線型編碼器 所得到的磁性特性的極性變化點；在該極性變化點的位置 ，使前述可動子停止，形成前述線型馬達之絕對位置的基 準位置。 又，藉由本發明之另一形態，提供一種線型馬達之原 點設定方法，係爲在圓筒狀構件的中空部，具有：將複數 個永久磁鐵的同一磁極互相面對面的緊密貼合，直列狀配 置所構成的磁軛、和具有與前述磁鐵列隔著磁性空隙而面 對面配置的電樞線圈的電樞、和配設在前述磁鐵列的端部 或中途，使前述磁鐵列的磁性特性急遽變化的磁性特性急 變部、和以前述磁鐵列構成磁性標度部，將兩個前述永久 磁鐵間的長度，設定成前述磁性標度部的標度間距，並且 互相的以電角度錯開90° (相當於標度間距的1 / 4波長） 來配置相位的複數個第1磁性檢測器、和從該第1磁性檢 測器以電角度錯開1 80° (相當於標度間距的1 / 2波長） -10- 200908536 來配置相位的第2磁性檢測器之沿著前述電樞的長邊方向 所具有的位置檢查用的磁性式線型編碼器；前述磁軛與前 述電樞的任一方爲固定子，另一·方爲可動子’在即述電樞 側具備前述磁性式線型編碼器的標度頭，使前述磁軛與前 述電樞相對性的直線移行的線型馬達之原點設定方法，其 特徵爲：使前述可動子沿著原點方向移動，搜尋前述磁鐵 列之磁性特性產生急遽變化的磁性特性急變位置；以該磁 性特性急變位置爲基礎，來設定用以設定原點的原點設定 基準位置；從該原點設定基準位置開始使可動子以既定的 減速來減速，使其暫停在前述標度頭爲既定値的位置；更 從該停止位置開始使前述可動子沿著原點方向移動，來搜 尋由前述磁性式線型編碼器所得到的磁性特性的極性變化 點；在該極性變化點的位置，使前述可動子停止，形成前 述線型馬達之絕對位置的基準位置。 進而，藉由本發明之另一形態，提供一種線型馬達之 原點設定方法，係爲在圓筒狀構件的中空部，具有：將複 數個永久磁鐵的同一磁極互相面對面的緊密貼合，直列狀 配置所構成的磁軛、和具有與前述磁鐵列隔著磁性空隙而 面對面配置的電樞線圈的電樞、和配設在前述磁鐵列的端 部或中途，使前述磁鐵列的磁性特性急遽變化的磁性特性 急變部、和以前述磁鐵列構成磁性標度部，將兩個前述永 久磁鐵間的長度，設定成前述磁性標度部的標度間距，並 且互相的以電角度錯開90° (相當於標度間距的1 / 4波長 )來配置相位的複數個第1磁性檢測器、和從該第1磁性 -11 - 200908536 檢測器以電角度錯開1 80° (相當於標度間距的 )來配置相位的第2磁性檢測器之沿著前述電 向所具有的位置檢查用的磁性式線型編碼器； 前述電樞的任一方爲固定子，另一方爲可動子 樞側具備前述磁性式線型編碼器的標度頭，使 前述電樞相對性的直線移行的線型馬達之原點 其特徵爲：使前述可動子沿著原點方向移動， 鐵列之磁性特性產生急遽變化的磁性特性急變 磁性特性急變位置爲基礎，來設定用以設定原 定基準位置；從該原點設定基準位置開始使可 的減速來減速，使其暫停在前述標度頭爲既定 以前述原點設定基準位置爲前述線型馬達之絕 準位置。 [發明效果] 藉由本發明，根本不需要限制開關或鎖簧 整、設定作業，線型馬達組裝結束的時候，作 點設定結束，故能排除藉由人工的設定及調整 供再現性佳且穩定的線型馬達之原點設定方法 【實施方式】 [用以實施發明的最佳形態] 以下，針對本發明之實施形態，邊參照圖 明。再者，於各圖中，針對同一處附上相同符 1 / 2波長 樞的長邊方 前述磁軛與 ，在前述電 前述磁軛與 設定方法， 搜尋前述磁 位置；以該 點的原點設 動子以既定 値的位置； 對位置的基 的安裝、調 業也隨著原 作業，可提 面、邊做說 號，並且省 -12- 200908536 略重複的說明。適用有關本發明之原點設定方法的線型馬 達，係以磁轭（field yoke)和電樞（armature)的任一方 爲固定子、另一方爲可動子，使磁軛和電樞相對性的直線 移動。在以下所描述的實施形態中，爲了方便說明，雖以 磁軛爲固定子，電樞爲可動子，但本發明並非限定於該等 實施形態而解釋。 第1圖是表示採用實施本發明之磁式線型編碼器的線 型馬達之槪略構造的前視圖。又，第2圖是第1圖中之 A - A的剖面圖。 如第1圖、第2圖所示，線型馬達1係具備：形成底 座的底座部2、和用以引導線型馬達1朝直線方向移動的 線型引導部3。線型引導部3係由安裝在底座部2的導軌 3 A、和在導軌3 A上滑動的滑塊3 B所構成。在滑塊3 B的 上面，例如載置著用以安裝應用線型馬達1的機械和裝置 的工作台3 C。 在底座部2配設著構成線型馬達1的固定子（固定部 )’使其產生磁場的磁軛4。磁軛4係由緊密貼合插入到 圓筒狀構件（套筒）6與圓筒狀構件6的中空內部的圓柱 狀永久磁鐵8的磁鐵列所構成。複數的永久磁鐵8爲分別 具備相同一形狀、尺寸的構件。各個永久磁鐵8係在圓筒 狀構件6的長邊方向被磁化。磁鐵列，係使相鄰的永久磁 鐵8以同磁極（彼此爲N極-N極或者s極-S極）互相的 面對面，且密著的狀態下，排列複數個所構成。線型馬達 1之移動方向的長度’亦即最大移動距離，係將可動子的 -13- 200908536 長度拉長至排列的永久磁鐵8之磁鐵列的長度。 銨系作爲磁鐵的種類最適合。再者，永久磁鐵8並不 限於圓柱狀，亦即實心的磁鐵，例如也可爲圓筒形的磁鐵 。像這樣，因永久磁鐵8的同磁極，互相的密著面對面配 置，所以產生非常強的反彈力。如第8圖所示，藉由模擬 求得相關之永久磁鐵8之磁性特性。第8圖是表示合成磁 場的空間分佈特性，橫軸方向是表示圓筒狀構件6的軸向 距離，縱軸方向是表示使同極磁鐵密著時的合成磁場。形 成在圓筒狀構件6之半徑方向，垂直進出圓筒狀構件6之 表面的磁束成份，對隔著空隙面對面配置的電機子線圏1 2 形成有效磁束。可是，有關本發明之實施形態的線型馬達 1，同極彼此的磁束在密著面碰合，所以與磁鐵外周部之 磁束比較的話，接近磁鐵中心的磁束，係受到來自相對之 方向產生相對應磁鐵之磁場的影響。因此，接近磁鐵中心 的磁束，會因相互的反斥朝向與對應磁石相反的方向彎曲 。其結果，推測僅彎曲的成份自圓筒狀構件6的半徑方向 偏移，從圓筒表面進出，對電樞線圈（armature coil) 12 的有效磁束減少。 圓筒狀構件6是以非磁性體所構成，其相對磁導率（ relative magnetic permeability) 2_0 以下爲宜。以磁性體 構成圓筒狀構件6的話，磁束大部分會流經以永久磁鐵8 列—圓筒狀構件 6 —永久磁鐵 8列所構成的磁路（ magnetic circuit )，到達電樞線圏1 2的有效磁束減少。 在線型馬達1的可動子（可動部）1 0，形成有插通圓 -14- 200908536 筒狀構件6的插通孔，構成可沿著圓筒狀構件6的長邊方 向移動。可動子1 0，係以電樞、收納電樞的框體、安裝在 框體的磁性式線型編碼器（線型感測器）所構成。在電樞 安裝著三相電樞線圈1 2。 第3圖是由線型馬達1的側面觀看的槪略圖，第6圖 是第3的一部分之放大圖。在磁性式線型編碼器，係具備 用以形成爲了檢測可動子之位置的磁極圖形的磁性標度部 、和檢測磁性標度部之磁極圖形的標度頭。如第3圖所示 ，在本實施形態中，並非分別將磁性標度部和標度頭各別 二等份的配設在底部，使用於線型馬達1之磁軛4的永久 磁鐵8列，是構成兼用磁性式線型編碼器1 6之被檢測體 的磁性標部部1 9。進而，如第3圖及第6圖所示，使兩個 永久磁鐵8緊密貼合之構造時的長度Lp，是構成磁性標 度部19的標度間距Lp。 在可動子1 0側亦即電樞線圈1 2的一端部，將磁性式 線型編碼器1 6的標度頭1 8安裝在線型馬達1的原點側。 在此，原點側意思是當線型馬達1從現在位置開始移動時 ，表示位置的資訊量大增的方向離開原點，減少的方向靠 近原點。再者，標度頭1 8的安裝位置不限於上述，例如 也可安裝在可動子10的中心位置。 磁性式線型編碼器1 6，係爲了檢測來自固定子之永久 磁鐵8列的磁束，具備兩個第1磁性檢測部14。各個第1 磁性檢測部1 4 ’係配置成以電角度互相的具有90°相位差 (相當於標度間距Lp之1 /4波長），其輸出訊號爲二相 -15- 200908536 行 的 該 訊 爲 置 變 理 性 配 ( 20 係 測 這 的 急 14 的 束 。藉此’可檢測出線型馬達1的電角度與線型馬達1的 進方向。 由該等第1磁性檢測部14，輸出標度頭1 8之現在 位置資訊之位址的二相正弦波的類比訊號da、db。作爲 等第1磁性檢測部1 4，係以能將磁性直線式的變換爲電 號的霍爾元件最適合。進而，在磁性式線型編碼器i 6， 了 fe測磁丨生特性急變部3 2 (於後述）的磁性特性急變位 ’沿著電樞的長邊方向在標度頭1 8內設有磁性特性急 位置檢測部22。磁性特性急變位置檢測部22是用來處 、判定來自第1磁性檢測部丨4的訊號以及來自第2磁 檢測部20的訊號。 第2磁性檢測部20，係沿著線型馬達1的移動方向 置成對第1磁性檢測部14，以電角度的相位錯開！ 8〇, 相當於標度間距Lp之1 /2波長）。由第2磁性檢測部 輸出正弦波的類比訊號dc。作爲第2磁性檢測部2〇， 以能將磁性直線式的變換爲電訊號的霍爾元件最適合。 磁性特性急變位置檢測部22，係例如以第2磁性檢 部20的輸出訊號dc、和加上Lp/2波長部份、位置偏移 方的第1磁性檢測部14 (參照第6圖）的輸出訊號da 加法電路（圖未示）、和由該加法結果來判定磁性特性 變位置的比較告？（圖未示）所構成。 如第4圖沿著磁軛4表示從兩個第I磁性檢測部 輸出的類比訊號da、db以及從第2磁性檢測部20輸出 類比訊號dc的波形。於第4圖中，縱軸方向係表示磁 -16- 200908536 密度ΒΓ，橫軸方向係表示標度頭丨8的位置，縱軸方向係 表示來自該位置的永久針磁_ 8列的有效磁束的磁束密度 Br。進而，如第7圖（a )部分放大由原點周邊的第i磁 性檢測部1 4輸出的類化訊號d a、d b波形。 其次，針對有關本發明的實施形態的線型馬達丨的驅 動系統5 0做說明。第丨〇圖是表示驅動系統之構造例的方 塊圖。如第10圖所示，該驅動系統5 〇係由馬達驅動控制 裝置（輔助驅動器）3 0、磁性特性急變位置檢測部2 2、位 置資訊變換器28、可寫入記憶體等的固定記憶部3丨所構 成。連接輸入從第1磁性檢測部14輸出的二相正弦波的 類比訊號da、db ’變換爲位置資料的位置資訊變換器2 8 、和藉由從外部對線型馬達丨指示的位置指令（圖未示） 與以位置資訊變換器2 8所得到的標度頭1 8的現在位置的 訊號P 〇 s ’來演算對電樞線圈1 2的電流指令的馬達驅動控 制裝置3 0。 馬達驅動控制裝置（伺服傳動裝置）3 〇，係例如以中 央演算裝置（或微處理器）、ROM、RAM、輸出入電路、 以及必v放大器（po wer amplifier )等所構成。 依據來自第1磁性檢測部1 4的磁性訊號，邊控制流 入線圈的電流、邊驅動控制線型馬達i。 位置資訊變換器28，係輸入表示由安裝在電樞線圈 1 2之端部的標度頭1 8讀取的可動子1 〇的現在位置的類比 訊號’亦即由第1磁性檢測部1 4輸出的二相正弦波的類 比訊號da、db，變換成位置資料。該位置資訊變換器28 -17- 200908536 爲位置變換器’並且亦爲表示標度頭1 8之現在位置的位 置計數器。位置資訊變換器2 8，係完成返回原點時，接受 由馬達驅動控制裝置3 0輸出的重置訊號，作爲位置計數 器的値爲零。 馬達驅動控制裝置30’係依據標度頭18之現在位置 的資訊pos來演算電流指令，將控制電流經由給電線（圖 未示）輸送到可動子，來控制可動子的目標位置及移動速 度。 再者’在上述的說明中，雖然位置資訊變換器2 8，係 獨立作爲驅動系統5 0之一構成要件，但不限於此，可也 配設在磁性式線型編碼器1 6的內部。也可將磁性式線型 編碼器1 6作爲馬達驅動控制裝置3 0之一構成要件，配設 在其內部。又，相反的，也可將馬達驅動控制裝置3 0作 爲磁性式線型編碼器1 6之一構成要件，配設在其內部。 磁性特性急變位置檢測部22，係輸出從第1磁性檢測 部14輸出的類比訊號da以及從第2磁性檢測部20輸出 的類比訊號dc，來加法演算兩訊號。 類比訊號d a與類比訊號d c，相位偏移1 8 0度，爲d a 与dc的關係。因而’兩者相加的話，相互抵消，在永久磁 鐵8緊密貼合之處，加法訊號ac的大小接近零。不是零 ，是因各個永久磁鐵8的磁性特性和形狀、在第1磁性檢 測部1 4、第2磁性檢測部20具有誤差。 而且，處理（例如閾値處理）該加法訊號ac的大小 ’來檢測磁性特性急變位置。而且，由於在磁性特性急變 -18- 200908536 位置’ da与dc的關係崩解，因此da+ dc成爲較大的輸出 訊號。如第5圖’表示該加法訊號亦即合成感測器輸 出’在磁輕4的整個範圍內沒有什麼變化。又，如第7圖 (a ) ’放大在原點周邊的加法訊號ac的波形。對應於上 述的閾値處理（threshold processing )，磁性特性急變位 置檢測部22 ’係將磁性特性急變位置檢測訊號dth以及超 出訊號do v輸出到馬達驅動控制裝置3 〇。又，上述的閾値 處理可配合應用該線型馬達的運送裝置所要求的精度做適 當設定。 再者’也可將磁性特性急變位置檢測部2 2作爲磁性 式線型編碼器1 6之一構成要件，配設在其內部。進而， 因可將磁性式線型編碼器1 6作爲馬達驅動控制裝置3 0之 一構成要件’配設在其內部，故磁性特性急變位置檢測部 2 2也可配設在馬達驅動控制裝置3 〇的內部。 有關本發明之實施形態的線型馬達，如第3圖所示， 在緊密貼合排列複數個永久磁鐵8的兩端部，設有磁性特 性急變部32爲磁軛4的一部分。再者，第3圖中，設置 在左端的磁性特性急變部3 2，係利用於線型馬達的原點位 置檢測用’設置在右端的磁性特性急變部3 2，係利用作爲 超出位置檢測用。 磁性特性急變部3 2，係以非磁性體所構成，也可以磁 性體所構成。再者，相對磁導率r 5 0以上的材料爲宜，若 爲相對磁導率r 1 0 0以上的材料更佳，相對磁導率r 1 〇 〇 〇 〇 以上的材料最適合。 -19- 200908536 又’作爲磁性特性急變部3 2的材質，例如 合金、銅合金、非磁性不銹鋼（例如 SUS 3 04 ) 性材料。進而，作爲相對磁導率高的磁性體材料 是利用磁性不銹鋼、軟鋼、矽鐵B F Μ、碳鋼或低 雖然可應用磁性特性急變部32的線型馬達 方向之厚度（長度），比一個永久磁鐵8的磁化 度還短者，但應用比永久磁鐵8的磁化方向之長 爲宜。藉由磁性特性急變位置檢測部22穩定的 特性急變位置。磁性特性急變部3 2具有與圓筒 之內徑大致相同大小的外徑，在外周部塗佈接著 圓筒狀構件6的一端壓入，並利用鉚接固定或固 狀構件6爲宜。 假設不在永久磁鐵8列的端部配設磁性特性 ，形成空隙時，出現在端部的磁束，會馬上回到 的永久磁鐵8本身的異極。對此，在永久磁鐵8 配設磁性特性急變部3 2的情形下，出現在端部 會通過磁性特性急變部3 2，回到位在端部的永久 身的異極。而且，如果磁性特性急變部3 2的材 的相對磁導率的話，描繪出現在端部之磁束的廻 〇 而且，磁性檢測器對於與此直交的磁束，會產生 應。 亦即，由第3圖所示的永久磁鐵8列與磁性 部32的排列、以及第5圖所示的合成感測器輸t 可利用鋁 等的非磁 ，更理想 碳鋼等。 1的移動 方向之長 度更長者 檢測磁性 狀構件6 劑後，從 接在圓筒 急變部3 2 位在端部 列的端部 的磁束， 磁鐵8本 料爲較高 路更明顯 較大的反 特性急變 B ac的波 -20- 200908536 形即可明白’依據可動子10的移動指令，移動方向X和 合成感測器輸出ac的輸出訊號兩邊都監視，藉此產生可 動子1 〇之超出的情形，就能檢查。在第3圖所示的永久 磁鐵8列的左端部或右端部，產生可動子1 〇之超出的情 形，如第5圖所示，了解到合成感測器輸出ac的輸出會 急速增大。於是，藉由變化磁性特性急變位置檢測部22， 閾値處理合成感測器輸出ac的的輸出大於既定大小產生 變化的狀態，藉此就能檢測可動子1 0的超出狀態。在此 的閾値處理例如可配合應用該線型馬達的運送裝置所要求 的精度做適當設定。 如此一來，通常的運轉控制中，可動子1〇是在第3 圖的右端沿著右方向移動中，藉由磁性特性急變位置檢測 部22，利用閾値處理來檢測第5圖所示的右端位置χ4的 情形下，可將該位置x4應用於可動子1 0之右端部超出狀 態的檢查。藉由同樣的處理，通常的運轉控制中，可動子 1 〇在第3圖的左端沿著左方向移動中，利用閾値處理來檢 測原點設定基準位置X 1 (於後述）的情形下，可將該位置 應用於可動子1 〇之左端部超出狀態的檢查。 如第3圖、第6圖所示，作爲磁性特性急變部3 2，於 第1 1圖的曲線ga表示使用與在圓筒狀構件6之內部具有 與永久磁鐵8大致相同大小之直徑的中間實心的非磁性不 銹鋼的S U S 3 0 4 (相對磁導率1 . 〇 0 0 8 )時的類比訊號的加 法訊號ac。於第1 1圖中’橫軸表示標度頭的位置’縱軸 表示合成感測器輸出訊號的大小。 -21 - 200908536 在此，說明磁性特性急變部的變形例。第1 3圖所示 的磁性特性急變部32b，係在軸心部使用相對磁導率 r= 1 0 0 0 0的高相對磁導率磁性體3 3，其直徑爲永久磁鐵8 之一半的大小，在其外側使用非磁性不銹鋼（SUS3 04 ) 34 。像這樣於第1 1圖的曲線gb表示構成磁性特性急變部 3 2b時的類比訊號的加法訊號ac。 進而，第1 4圖所示的磁性特性急變部3 2c，係使用相 對磁導率r= 1 0000的高相對磁導率磁性體，其直徑爲與永 久磁鐵8相同的大小。於第1 1圖的曲線gc表示該變形例 的類比訊號的加法訊號ac。由第1 1圖所示的磁性特性曲 線群g a〜g c即可理解，也可利用非磁性體或磁性體的任 何材料作爲磁性特性急變部的材質。 根據以上情形，有關改變磁性特性急變部材質時的磁 性特性’如第1 2圖表示發明人等所進行的模擬結果。由 弟1 2圖所不的模擬結果’可理解至少利用包含相對磁導 率r爲5 0以上之磁性體的材料爲宜，利用包含相對磁導 率r爲1 〇 〇以上之磁性體的材料更佳，利用包含相對磁導 率r爲1 〇 〇 〇 〇以上之磁性體的材料更佳。 又’有關磁性特性急變部的位置，並不限於上述的實 施形態’當然可有幾種變化。例如不是磁鐵列的端部側， 可在磁軛的中途配設磁性特性急變部。進而，也可在磁鐵 列的端部側與磁軛的中途，於複數處配設磁性特性急變部 -22- 200908536 <原點設定及原點設定動作> 其次，針對如上所構成的線型馬達之原點設定及原點 設定動作做說明。 在通常的狀態，利用位置資訊變換器28來演算可動 子1 0的現在位置。而且，電源爲OFF再起動的情形、自 底部2取出可動子10，然後再度將可動子10安裝在底部 2的情形等，無法演算可動子1 0的絕對位置。在位置資訊 變換器2 8，用來演算絕對位置的基準位置會偏移。於是， 在有關本實施形態的線型馬達，欲再度設定基準位置加以 確定的返回原點作業，不用透過操作員，能自動的實行。 第1 5圖至第1 8圖，係分別表示有關本實施形態的線 型馬達1的原點設定之流程的流程圖。因原點設定時’原 點設定的手法因可動子1 0與磁性特性急變部3 2的位置關 係而不同，所以分成各種情形說明。 第1 5圖係表示返回原點開始前，可動子1 0全部沿著 磁性特性急變部3 2方向通過原點時的原點設定之流程。 再者，假定原點是在第15圖所示的位置。 首先，由設置在馬達驅動控制裝置3 0的操作盤（圖 未示），藉由手冊指令，或是線型馬達運轉程式中的程式 指令’對馬達驅動控制裝置3 0輸出返回原點指令（步驟 S 1 0 1 ) ° 其次，馬達驅動控制裝置3 0內的微處理器等的控制 手段’係磁性特性急變位置檢測部22來檢測磁性特性急 變部3 2 ’檢測可動子1 〇沿著磁性特性急變部3 2方向通過 -23- 200908536 原點（步驟S 1 0 2 )。再者，在本實施形態中，磁性特性 急變部3 2，爲兼用檢測線型馬達1之端部的端部檢測部的 構造。 其次，實行事先設定記憶之出現原點用的順序程式， 依舊使線型馬達1的可動子1 0沿著靠近原點的方向移動 ，通過原點，進而使可動子1 〇沿著離開原點的方向，僅 移動既定距離（步驟S103)。除去第15圖所示的原點位 置。在此，作爲既定的距離例如磁性式線型標度的1至數 標度間距，例如相當3標度間距的距離最適合。只要除去 原點之位置的距離就很充分。 而且，線型馬達1沿著原點方向以微低速驅動，使可 動子1 〇沿著原點方向移動，藉由磁性特性急變位置檢測 部22來處理（例如閾値處理）從第2磁性檢測部20輸出 之距離1 /2標度間距（Lp/2 )的兩點間的類比訊號的加法 訊號ac，搜尋（search )磁性特性急變位置（步驟S104 ) 。在此的加法訊號係加上彼此1 80度相位不同的訊號，來 演算兩點間的磁性特性之差。 其次，以加法結果的値Vb大於既定値的位置，作爲 原點設定基準位置X 1 (步驟S 1 0 5 )。如此一來，可藉由 磁性特性急變位置檢測部2 2 ’來檢測原點設定基準位置 X 1。該原點設定基準位置x 1 ’不是磁性特性急變部3 2與 永久磁鐵8的邊界’偏離此。此爲根據如下的理由。亦即 ，因爲磁性特性急變部3 2與永久磁鐵8的邊界附近爲波 形ac的峰値，所以其位置可爲X1。可是’峰値會因各個 -24 - 200908536 磁軛有誤差。因此，以某一磁軛的峰値爲代表，設定閾値 時’有可能在別的磁鞭會因誤差達不到該閾値。於是，以 波形ac之中段附近爲閾値最適合，磁性特性急變部3 2與 永久磁鐵8的邊界附近錯開X 1最適合。 <有關既定値> 在此，既定値可如下設定。首先，在線型馬達1，具 有所使用的永久磁鐵8之各個尺寸的誤差、永久磁鐵8著 磁時的磁性特性的誤差、以及永久磁鐵8插入至圓筒狀構 件6組裝時所產生的永久磁鐵固定位置的誤差。考慮該等 誤差的話，在除了直線狀排列的永久磁鐵8列的兩端及原 點周邊的移動範圍內觀測之比從第1磁性檢測器1 4及第2 磁性檢測部20輸出的兩個類比訊號da、dc的加法訊號的 變動寬Vb大5 %的値，亦即以1.05 Vb爲既定値就能利用 。根據發人等進行的實驗，只要是比加法訊號ac的變動 寬Vb大10%的値=1.1 Vb，就能更穩定的設定原點，只要 是比兩個類比訊號的加法訊號ac的變動寬Vb大25 %的値 =1 . 2 5 V b 更佳。 判定原點設定基準位置X1的話，從該X1開始使可動 子1 0以事先決定的減速來減速，以可動子1 0停止的位置 爲標度頭的位置χ2(參照第7圖（b)、第7圖（C))。 該減速例如爲事先設定記憶在馬達驅動控制裝置3 0內的 微處理器等的控制手段最適合。再者，減速大的話，在x2 的可動子停止時會發生過大的超越量（overshoot)，有傷 -25- 200908536 及場軛端部之虞。又，減速太小的話，到達 是，在磁軛內停止的減速爲適當的値。 其次，使可動子1 〇從標度頭的現在位§ 向反轉（步驟S106 )。 有關停止位置x2的二相正弦波類比訊 碼器的A相訊號da及B相訊號db，使用^ ，針對標度頭的位置xh進行計算。 X h (Lp/27i)f(db/da) ...(1) 但在式（1)中，f(db / da)定義爲下 〜式（1 d )。 f(db/da)= atan(db/da)-7t/2|dag〇,db2〇 f(db/da)= atan(db/da) + 7i/2|da<0,db 2 Ο f(db/da)= at an (db / d a)+ π/2 I d a<0，db < Ο ·· f(db/da)= a t an (db/d a) - π/2 I d a ^ 0 , d b < 0 ·· 可動子1 0的停止位置x2，係求得的標 置hp A，在第7圖（a)或第7圖（c)的 z e r 〇)的話，形成槪括値，以下記的列式表; x2 = -xh ·· (2) 大致等於上記列式（1 )的xh。再者’ 算在1^八±標度間距/ 2的範圍很有效。 可動子10從現在位置X 2沿著第7圖 (與目前相反的方向）以微速移動，重複葬 搜尋二相正弦波類比訊號的極性變化點（步 時間增大。於 【x2讓移動方 號的磁性式編 =記的式（1 ) 記的式（1 a ) ...(la) ... (lb) .(lc) •(Id) 度頭的原點位 X軸上爲0 ( 上記的位置計 (b )的右方向 章算式（1 )， 驟 S 1 0 7 )。 -26- 200908536 在可動子1 0到達極性變化點，亦即xkO的位置（第 7圖（c)中’ χ3的位置）’停止可動子1〇，重置標度頭 的現在位置計數器（步驟S 1 0 8 )。 再者，在上記式（1)中’雖然有關求得的標度頭之 原點位置hpA，在X軸向爲〇(zero)，但以該〇點替換 爲弟7圖（a )所不的波形的任何位置，改變定義，當然 式（la)〜（Id)的「π/2」的値也會變。 又，在各個永久磁鐵8具有尺寸上的誤差、磁化特性 的誤差等的情形下，爲了解決因該等誤差的影響，可針對 求得的原點位置phA，進行所要的修正。針對該修正的手 法，因並非本發明的主旨，故在此不於詳述 於是，在本實施形態中，線型馬達1之組裝作業結束 的時候，不用操作者就能實現線型馬達1之絕對位置的基 準位置（點）的原點x3=phA，就能自動的實現原點設定 處理。因而，如以往爲了原點設定之藉由操作員的追加作 業，一切都不會發生。 其次，第1 6圖係表示在返回原點開始前，可動子1 0 不在磁性特性急變部3 2之位置時的原點設定之流程。在 位於此種位置關係的情形下，可動子10會超過原點位置 ，移動到磁性特性急變部3 2，再度朝向原點位置移動。 首先，藉由線型馬達運轉程式中的程式指令，對馬達 驅動控制裝置3 0輸出返回原點指令（步驟S20 1 )。 其次，使線型馬達1沿著原點方向驅動’使可動子1〇 沿著原點方向移動，藉由磁性特性急變位置檢測部22來 -27- 200908536 處理（例如閾値處理）從第2磁性檢測部2 〇輸出之距離 1/2標度間距（Lp/2 )的兩點間的類比訊號的加法訊號ac ’搜尋磁性特性急變位置（步驟S2〇2 )。 其次’以加法結果的變動寬vb大於既定値的位置， 作爲原點設定基準位置xl (步驟S2〇3 )。 判定爲原點設定基準位置χ 1的話，使可動子1 〇從該 X 1開始減速，停在標度頭位置χ2。 其次’使可動子1 0從標度頭的現在位置χ2沿著原點 方向（與目前相反的方向）以微速移動（步驟s 2 04 )， 演算上記的式（1 ) ’來捜尋二相正弦波類比訊號的極性 變化點（步驟S 2 0 5 )。 可動子1 〇到達極性變化點的話，使可動子1 〇停止， 重置現在位置計數器（步驟S206 )。 其次’第1 7圖係表示磁性特性急變部3 2在磁軛的中 途’且配設在比原點位置更靠近內側時的原點設定之流程 。在位於此種位置關係的情形下，可動子1 〇會超過位於 配設在磁軛之中途的磁性特性急變部3 2而移動，直至移 動到原點位置。 首先’藉由線型馬達運轉程式中的程式指令，對馬達 驅動控制裝置30輸出返回原點指令（步驟S301)。 其次，使線型馬達1沿著原點方向驅動，使可動子1 〇 沿著原點方向移動，藉由磁性特性急變位置檢測部2 2來 處理（例如閾値處理）從第2磁性檢測部2 0輸出之距離 1 /2標度間距（Lp/2 )的兩點間的類比訊號的加法訊號ac -28- 200908536 ，捜尋磁性特性急變位置（步驟S3 02 )。 其次，以加法結果的變動寬Vb大於既定値的位置， 作爲原點設定基準位置χΐ (步驟S3 03 )。 設定爲原點設定基準位置X1的話，使可動子10從標 度頭的現在位置X1沿著原點方向以微速移動’演算上記 的式（1 )，搜尋二相正弦波類比訊號的極性變化點（步 驟 S 3 0 4 )。 可動子1 0到達極性變化點的話，使可動子1 〇停止> 重置現在位置計數器（步驟S 3 0 5 )。 其次，第1 8圖係表示磁性特性急變部3 2在磁軛的中 途，且配設在比原點位置更靠近外側時的原點設定之流程 。在位於此種位置關係的情形下，可動子1 〇會超過原點 而移動，在位於配設在磁軛之中途的磁性特性急變部3 2 的位置，改變移動方向，直至移動到原點位置。 首先’藉由線型馬達運轉程式中的程式指令，對馬達 驅動控制裝置30輸出返回原點指令（步驟S4〇l )。 使線型馬達1沿著原點方向驅動，使可動子1 〇沿著 原點方向移動’藉由磁性特性急變位置檢測部22來處理 (例如閾値處理）從第2磁性檢測部2 0輸出之距離\丨2 標度間距（Lp/2 )的兩點間的類比訊號的加法訊號ac，搜 尋磁性特性急變位置（步驟S 4 0 2 )。 其次’以加法結果的變動寬Vb大於既定値的位置， 作爲原點設定基準位置X 1 (步驟s 4 0 3 )。 判疋爲原點設定基準位置X1的話，使可動子1 〇從該 -29- 200908536 X 1開始減速，停在標度頭位置X2。 其次，使可動子10從標度頭的現在位置Χ2 方向（與目前相反的方向）以微速移動（步驟 演算上記的式（1 )，搜尋二相正弦波類比訊號 化點（步驟S405 )。 可動子1 〇到達極性變化點的話，使可動子 重置現在位置計數器（步驟S 406 )。 再者，無論在上述的任一個外殼，在設定線 之絕對位置的基準位置（點）之原點hpA的時候 LED等的發光手段點亮既定期間。或者，將使蜂 可聽頻率的發音手段動作，告知外部的告知手段 磁性式線型編碼器1 6的話，適合易於藉由操作 原點設定處理結束。 <變形例> 在上述的原點設定中，採用在原點附近減速 的低速，停留在原點設定誤差極小的範圍，能事 位置X2很遠的返回距離的演算方法。除此之外， 圖（a )的範例中，二相正弦波類比A相訊號d a 號db，求得極性由正變負（或負變正）的位置， 原點設定的處理。 進而，在藉由磁性特性急變位置檢測部22， 設定基準位置xl之後，重置位置資訊變換器28 設定基準位置x 1爲原點加以利用’位置精度略 沿著原點 S404 )， 的極性變 1 0停止， 型馬達1 ，都能使 鳴器等之 ，附設在 員來確認 至極微小 先掌握離 亦在第7 或B相訊 都能完成 檢測原點 ，以原點 粗，亦可 -30- 200908536 在充分的利用範圍採用。 藉由本實施形態，爲了演算線型馬達之絕對位置的基 礎的原點設定，完全不需要以往必須具有人工之作業，亦 即附設限制開關或鎖簧的安裝、調整、設定作業。又，線 型馬達之組裝結束的時候，原點設定關係的組裝及安裝作 業亦同時全部結束完成。 進而，根據線型馬達的永久磁鐵周邊及周圍的磁場分 佈或磁場特性，自動的檢查磁性特性急變位置，就能簡單 且正確的完成原點設定。 亦即，原點設定時，不需要操作員，因作業員之能力 的原點設定作業之誤差等亦能排除，就能完成再現性佳、 穩定的線型馬達的原點設定。 再者，本發明依舊不限於上述的實施形態，在實施階 段，在不脫離該主旨的範圍內，能變形並將構成要素具體 化。又，可藉由上述之實施形態所揭示的複數個構成要素 的適當組合，形成各種發明。例如，也可從實施形態所示 的所有構成要素中，取消幾個構成要素。進而，也可適當 組合不同之實施形態的構成要素。 【圖式簡單說明】 第1圖是表示有關第1實施形態的線型馬達之槪略構 造的前視圖。 第2圖是第1圖中之A-A的剖面圖。 第3圖是有關第1實施形態的線型馬達之側面槪略圖 -31 - 200908536 第4圖是有關第1實施形態的第1磁性檢測部的輸出 波形。 第5圖是加上第1實施形態的第2磁性檢測部之輸出 的波形。 第6圖是有關第1實施形態的線型馬達之原點周邊的 部分放大圖。 第7圖（a )是第6圖之第1磁性檢測部的輸出波形 的部分放大圖，（b )是表示原點設定時之對可動子的運 轉指令的參考圖。 第8圖是表示使同極磁鐵面對面且緊密貼合時的合成 磁場之模擬結果的圖。 第9圖是表示使同極磁鐵面對面且緊密貼合，並且使 用高相對磁導率的圓筒構件時的合成磁場之模擬結果的圖 〇 第1 〇圖是表示有關本發明之實施形態的線型馬達之 驅動系統之構造例的方塊圖。 第1 1圖是表示配合相對磁導率而變化的合成感測器 輸出的圖。 第1 2圖是表示針對配合相對磁導率而變化的合成感 測器輸出而進行的模擬結果的圖。 第1 3圖是表示本發明之磁性特性急變部的另一構造 例的圖。 第1 4圖是表示本發明之磁性特性急變部的另一構造 -32- 200908536 例的圖。 第1 5圖是表示有關本實施形態的線型馬達的原點設 定之流程的流程圖。 第1 6圖是表示有關本實施形態的線型馬達的原點設 定之流程的流程圖。 第1 7圖是表示有關本實施形態的線型馬達的原點設 定之流程的流程圖。 第1 8圖是表示有關本實施形態的線型馬達的原點設 定之流程的流程圖。 【主要元件符號說明】 1 :線型馬達 4 :磁車尼 6 ’·圓筒狀構件 8 :永久磁石 1 0 :可動子 1 2 :電樞線圈 1 4、2 0 :磁性檢測部 1 6 :磁性式線型編碼器 18 :標度頭（scale head) 1 9 :磁性標度部 22 :磁性特性急變位置檢測部 2 8 :位置資訊變換器 3 0 :馬達驅動控制裝置 -33- 200908536 3 2、3 2 b、3 2 C :磁性特性急變部 5 0 :驅動系統 -34-BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for setting an origin of a linear motor, and more particularly to a method for setting an origin of a linear motor in which a magnetic linear encoder for repetitive positioning at a high speed is incorporated. [Prior Art] Most of the linear motors are used as the driving source of the moving mechanism and the transport mechanism. When using a linear motor, it is indispensable to check the moving position of the moving part of the linear motor. A line encoder is used as a means of checking the relevant moving position. Further, a method of converting the linear motion of the moving portion into a rotational motion and checking the moving position by the rotary encoder is also employed. The magnetic symbols or optical marks which are equally spaced are detected by the encoders, and the inspected marks are accumulated, interpolated and distributed between the two marks, and the amount of movement of the moving portion is checked. Although the encoders can detect the amount of movement of the moving portion, i.e., the amount of incremental search, the absolute position (position to the origin of a coordinate) cannot be checked. In order to check the absolute position, it is necessary to set the position where the accumulation of the mark and the accumulation of the interpolation signal become the reference. That is, the origin position of the moving part must be established. In the conventional method of establishing the origin position, the limit switch is set at a desired position on the fixed portion side of the in-line motor, and the moving portion is moved from a predetermined direction, and the position at which the switch is inspected is used as an origin to set the establishment. The method of locking the dog in the moving part. In addition, a method of setting the origin of a linear motor that does not use a restriction switch, a lock spring, or the like is also provided (see, for example, Japanese Patent Laid-Open Publication No. Hei. This is an in-line type motor in which a line type encoder is arranged in parallel, and as a position detector, an operator is placed at a position of a moving portion of the linear motor, and the operator is positioned at a low speed from the position. The part moves in a determined direction, and the bidirectional counter for calculating the current position is zeroed at a position where the polarity of the magnetic signal from the hall element is changed by the set number. This is the method by which the position detector checks the origin of the position. Furthermore, the linear motor using the optical linear encoder has a weak sense of detection due to adhesion of dust or stains, and is environmentally resistant, providing a high environmental resistance and low cost, and does not require a magnetic linear encoder. A linear motor that is set (for example, refer to Japanese Patent Laid-Open Publication No. 2). This is a magnetic field of a permanent magnet and a linear motor, and is composed of a magnetic scale of a linear encoder, and the pitch of the permanent magnet is set to a scale interval of the magnetic scale portion. Fighting against dust, etc. 'increased environmental resistance. [Patent Document 1] JP-A-2004-56892 [Patent Document 2] JP-A-2004-56892 SUMMARY OF INVENTION [Problems to be Solved by the Invention] The origin of the limit switch and the lock spring is set or the origin is used. Establishing the -6 - 200908536 method 'need to limit the switch and the lock spring, the position adjustment of the limit switch and the lock spring' must be performed by an operator. Further, in the method of establishing the origin disclosed in Japanese Patent Laid-Open No. 1, the operator uses a symbol that is roughly positioned at the determined position, first with the two symbols attached to the symbol of the moving member and the symbol attached to the fixed support portion. A method in which the width of one permanent magnet is roughly uniform, the rough positioning is performed by the operator, and then the origin setting/establishment processing of the linear motor is performed. Therefore, when the origin of the in-line motor is set, the operator must be placed and the various settings of the manpower are required. It is impossible to automatically perform the origin setting process. On the other hand, in the linear motor described in Japanese Patent Laid-Open No. 2, the setting of the magnetic linear encoder is not required, and the scale head of the magnetic linear encoder is configured to have an electric angle. A plurality of Hall elements formed by a phase shift of 90°, and a position information converter that converts the analog signal of the two-phase sine wave outputted by the Hall element into position data to calculate the current position of the movable element structure. However, the waveform of the induced voltage (inducedv ο 11 age ) and the waveform of the encoder signal as shown in the second diagram (a) of Patent Document 2 are such that only a plurality of permanent magnets are adjacent and regular at a predetermined interval. The principle of the arrangement of the central portion of the arrangement of the magnets at the ends of the magnet array is adopted. Therefore, only the encoder signal waveform is processed, and the origin for determining the absolute position of the linear motor cannot be set and established. Therefore, the linear motor described in Patent Document 2 is assumed by default on the basis of the means or technique for setting the origin of the position information converter for determining the absolute position. In addition, in the 200908536 Patent Document 2, "About the motor origin and origin setting" was not found any description. The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a method for setting an origin which can stably and easily realize setting and establishment of an origin for determining an absolute position of a linear motor. [Means for Solving the Problems] According to one aspect of the present invention, a method for setting an origin of a linear motor is provided in which a hollow portion of a cylindrical member has a surface in which the same magnetic poles of a plurality of permanent magnets face each other a yoke having an in-line arrangement and an armature having an armature coil disposed to face the magnet array with a magnetic gap therebetween, and an end portion or a middle portion of the magnet array a magnetic characteristic sharp portion in which the magnetic characteristics are rapidly changed, and a magnetic scale portion formed by the magnet array, and a length between the two permanent magnets is set to a scale pitch of the magnetic scale portions, and electrical angles to each other a plurality of first magnetic detectors that are shifted by 90° (corresponding to a 1/4 wavelength of the scale interval) to configure the phase, and electrically offset from the first magnetic detector by 180° (corresponding to a scale interval) a magnetic linear encoder for position inspection of the second magnetic detector in which the phase is disposed along the longitudinal direction of the armature; the yoke and the armature Either the stator is a stator and the other is a movable member, and the scale head of the magnetic linear encoder is provided on the armature side, and the linear motor in which the yoke is linearly opposed to the armature The origin setting method is characterized in that the movable member is moved along the origin direction, and the magnetic characteristics of the magnet array in which the magnetic characteristics of the magnet array are rapidly changed are searched for -8-200908536; the magnetic characteristic is changed based on the sharp position of the magnetic characteristic. The original origin setting reference position is set, and the predetermined deceleration can be decelerated from the origin setting reference position to stop the scale head as a predetermined position; and the movement of the movable member is started from the stop position. The direction is reversed to find the polarity point of the magnetic characteristic obtained by the magnetic linear encoder; at the position of the polarity change point, the movable member is stopped, and the reference position of the absolute position of the linear motor is formed. According to another aspect of the present invention, a method of setting a linear motor point is provided in a hollow portion of a cylindrical member, which has a structure in which the same magnetic poles of one permanent magnet are in close contact with each other and are arranged in series. a yoke, an armature having an armature coil disposed opposite to the magnetic gap between the magnet arrays, and a magnetic variator in which the magnetic properties of the magnet array are rapidly changed while being disposed in the middle of the magnet array The magnetic scale portion is configured by the magnet array, and the length between the two magnets is set to a scale pitch of the magnetic scale portion, and is electrically shifted by 90 degrees from each other (corresponding to a 1/4 wave of the scale pitch) a plurality of first magnetic detectors for arranging the phases, and a second magnetic detector that is shifted from the first magnetic detector by an electrical angle by 180° (corresponding to a 1/2 wave of the scale pitch) a magnetic linear encoder for position inspection of a long side of the armature; one of the yoke armatures is a stator, and the other is a movable member, and the magnetic linear encoder is provided on the side Scale head, said yoke so that the method of setting the origin point position of the mover of the linear motor armature linearly relative migration of bits, changes .. Dissatisfied Bu - < 八成B[J's original complex number is matched with the end of the end of the urgency and long). The direction and the front armature and the front, its -9-200908536 is characterized by: searching for the magnetic properties of the magnet column to produce rapid changes The magnetic characteristic is rapidly changed, and it is determined that the movable member passes through the origin in the direction of the magnetic characteristic sharp portion; the movable member is moved along the direction close to the origin to pass through the origin; and the movable member is further separated The direction of the origin is only moved by a predetermined distance; the movable member is moved along the origin direction to search for the sudden change position of the magnetic characteristic; and the origin setting reference position for setting the origin is set based on the sharp position of the magnetic characteristic. Starting from the origin setting reference position, the movable member is decelerated by a predetermined deceleration, and is stopped at a position where the scale head is a predetermined cymbal; and the movable member is moved along the origin direction from the stop position. Searching for a polarity change point of the magnetic characteristic obtained by the aforementioned magnetic linear encoder; at the position of the polarity change point, the aforementioned movable member Stop, the absolute position of the linear motor is formed of a reference position. Moreover, according to another aspect of the present invention, a method for setting an origin of a linear motor is provided in which a hollow portion of a cylindrical member has a close contact with a surface of a plurality of permanent magnets facing each other, and is in-line. Arranging the yoke and the armature having the armature coils disposed to face each other with the magnetic gap interposed therebetween, and the end portion or the middle of the magnet array, causing the magnetic properties of the magnet array to change rapidly The magnetic characteristic sharpening portion and the magnetic scale portion are formed by the magnet array, and the length between the two permanent magnets is set to a scale pitch of the magnetic scale portion, and is electrically shifted by 90° from each other (equivalent to a plurality of first magnetic detectors for arranging the phase at a wavelength of 1 / 4 of the scale interval, and an electrical angle of 1 80° from the first magnetic detector (corresponding to a 1/2 wavelength of the scale pitch) - 10-200908536 A magnetic linear encoder for position inspection along the longitudinal direction of the armature of the second magnetic detector in which the phase is disposed; any of the yoke and the armature The square is a fixed stator, and the other side is a movable member'. The scale head of the magnetic linear encoder is provided on the side of the armature, and the origin of the linear motor in which the yoke and the armature are linearly displaced is set. The method is characterized in that: the movable member is moved along the origin direction, and the magnetic characteristic of the magnet array is searched for a sudden change in the magnetic characteristic of the magnet string; and the magnetic characteristic sharp position is used to set the origin for setting the origin. Setting a reference position at the origin; starting from the origin setting reference position, decelerating the movable member with a predetermined deceleration, suspending the position where the scale head is a predetermined cymbal; and further moving the movable member along the stop position The origin direction moves to search for a polarity change point of the magnetic characteristic obtained by the magnetic linear encoder; at the position of the polarity change point, the movable member is stopped to form a reference position of the absolute position of the linear motor. Further, according to another aspect of the present invention, a method for setting an origin of a linear motor is provided in which a hollow portion of a cylindrical member has a close contact with a surface of a plurality of permanent magnets facing each other, and is in-line. Arranging the yoke and the armature having the armature coils disposed to face each other with the magnetic gap interposed therebetween, and the end portion or the middle of the magnet array, causing the magnetic properties of the magnet array to change rapidly The magnetic characteristic sharpening portion and the magnetic scale portion are formed by the magnet array, and the length between the two permanent magnets is set to a scale pitch of the magnetic scale portion, and is electrically shifted by 90° from each other (equivalent to a plurality of first magnetic detectors for arranging the phase at a wavelength of 1 / 4 of the scale interval, and an electrical angle of 1 80° (corresponding to a scale pitch) from the first magnetic-11 - 200908536 detector a magnetic linear encoder for position inspection of the second magnetic detector of the phase along the electrical direction; one of the armatures is a stator and the other is a movable The index head of the magnetic linear encoder is provided on the side, and the origin of the linear motor in which the armature is linearly displaced is characterized in that the movable member is moved along the origin direction, and the magnetic characteristics of the iron column are impatient. The changed magnetic characteristic is based on the sudden change of the magnetic characteristic of the magnetic characteristic, and is set to set the original reference position; the deceleration is decelerated from the origin setting reference position, and the pause is made in the aforementioned scale head. The point setting reference position is the absolute position of the aforementioned line motor. [Effect of the Invention] According to the present invention, it is not necessary to limit the switch or the lock spring and the setting work at all, and when the assembly of the linear motor is completed, the setting of the point is completed, so that it is possible to eliminate the need for manual setting and adjustment for reproducibility and stability. [Embodiment] [Best Mode for Carrying Out the Invention] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Furthermore, in each of the figures, the yoke with the long side of the same symbol 1/2 wavelength pivot is attached to the magnetic yoke and the setting method, and the magnetic position is searched for; Set the position of the mover to the established position; the installation and adjustment of the base of the position can also be done with the surface and side by the original work, and the explanation is slightly repeated from -12 to 200908536. A linear motor to which the origin setting method of the present invention is applied is a straight line in which one of a field yoke and an armature is a stator and the other is a movable member to make the yoke and the armature relatively linear. mobile. In the embodiments described below, for convenience of explanation, the yoke is a stator and the armature is a movable member. However, the present invention is not limited to the embodiments and will be explained. Fig. 1 is a front elevational view showing a schematic configuration of a linear motor using a magnetic linear encoder embodying the present invention. Further, Fig. 2 is a cross-sectional view taken along line A - A in Fig. 1. As shown in Fig. 1 and Fig. 2, the linear motor 1 includes a base portion 2 that forms a base, and a linear guide portion 3 that guides the linear motor 1 to move in a linear direction. The linear guide portion 3 is composed of a guide rail 3A attached to the base portion 2 and a slider 3B that slides on the guide rail 3A. On the upper surface of the slider 3 B, for example, a table 3 C for mounting a machine and a device for applying the linear motor 1 is placed. A yoke 4 that forms a magnetic field is formed in the base portion 2 by a stator (fixed portion) constituting the linear motor 1. The yoke 4 is composed of a magnet array that is tightly fitted to the cylindrical permanent magnet 8 inserted into the cylindrical member (sleeve) 6 and the hollow portion of the cylindrical member 6. The plurality of permanent magnets 8 are members each having the same shape and size. Each of the permanent magnets 8 is magnetized in the longitudinal direction of the cylindrical member 6. The magnet array is formed by arranging a plurality of adjacent permanent magnets 8 so as to face each other with the same magnetic poles (N pole-N pole or s pole-S pole mutually) and in a sealed state. The length of the moving direction of the linear motor 1, i.e., the maximum moving distance, lengthens the length of the -13-200908536 of the movable member to the length of the magnet array of the aligned permanent magnets 8. Ammonium is the most suitable type of magnet. Further, the permanent magnet 8 is not limited to a cylindrical shape, that is, a solid magnet, and may be, for example, a cylindrical magnet. In this manner, since the same magnetic poles of the permanent magnets 8 are arranged to face each other in close contact with each other, a very strong repulsive force is generated. As shown in Fig. 8, the magnetic characteristics of the associated permanent magnet 8 are obtained by simulation. Fig. 8 is a view showing the spatial distribution characteristics of the combined magnetic field. The horizontal axis direction indicates the axial distance of the cylindrical member 6, and the vertical axis direction indicates the combined magnetic field when the same-pole magnet is adhered. A magnetic flux component that enters and exits the surface of the cylindrical member 6 in the radial direction of the cylindrical member 6 is formed, and an effective magnetic flux is formed on the motor sub-wire 圏1 2 disposed to face each other across the gap. However, in the linear motor 1 according to the embodiment of the present invention, the magnetic fluxes of the same polarity are in contact with each other on the adhesion surface. Therefore, when the magnetic flux near the center of the magnet is compared with the magnetic flux at the center of the magnet, the magnetic flux near the center of the magnet is correspondingly generated from the opposite direction. The influence of the magnetic field of the magnet. Therefore, the magnetic fluxes close to the center of the magnet are bent toward each other in the opposite direction to the corresponding magnet due to mutual reciprocal. As a result, it is presumed that only the bent component is displaced from the radial direction of the cylindrical member 6, and the effective magnetic flux to the armature coil 12 is reduced from the cylinder surface. The cylindrical member 6 is made of a non-magnetic material, and has a relative magnetic permeability of 2_0 or less. When the cylindrical member 6 is made of a magnetic material, most of the magnetic flux flows through a magnetic circuit composed of a permanent magnet 8 column - a cylindrical member 6 - a permanent magnet 8 row, and reaches the armature wire 圏 1 2 The effective magnetic flux is reduced. The movable member (movable portion) 10 of the linear motor 1 is formed with an insertion hole through which the cylindrical member 6 is inserted into the circle -14 - 200908536, and is configured to be movable along the longitudinal direction of the cylindrical member 6. The movable member 10 is composed of an armature, a housing for housing the armature, and a magnetic linear encoder (linear sensor) attached to the housing. A three-phase armature coil 12 is mounted on the armature. Fig. 3 is a schematic view of the side of the linear motor 1, and Fig. 6 is an enlarged view of a portion of the third. The magnetic linear encoder includes a magnetic scale portion for forming a magnetic pole pattern for detecting the position of the movable member, and a scale head for detecting a magnetic pole pattern of the magnetic scale portion. As shown in Fig. 3, in the present embodiment, the magnetic scale portion and the scale head are not disposed in two at the bottom, and the permanent magnets in the yoke 4 of the linear motor 1 are arranged in eight rows. The magnetic target portion 1 9 constituting the object to be used of the magnetic linear encoder 16 is also used. Further, as shown in Figs. 3 and 6, the length Lp at the time of the structure in which the two permanent magnets 8 are closely attached is the scale pitch Lp constituting the magnetic scale portion 19. The index head 18 of the magnetic linear encoder 16 is attached to the origin side of the linear motor 1 at the movable member 10 side, that is, at one end of the armature coil 12. Here, the origin side means that when the linear motor 1 starts moving from the current position, the direction indicating that the amount of information of the position is greatly increased is away from the origin, and the decreasing direction is close to the origin. Further, the mounting position of the scale head 18 is not limited to the above, and may be attached to the center position of the movable member 10, for example. The magnetic linear encoder 16 is provided with two first magnetic detecting portions 14 for detecting magnetic fluxes from the permanent magnets 8 columns of the stator. Each of the first magnetic detecting portions 1 4 ′ is arranged to have a phase difference of 90° from each other at an electrical angle (corresponding to a 1/4 wavelength of the scale pitch Lp), and the output signal is a two-phase -15-200908536 line. For the anamorphism (20), the beam of the urgency 14 is measured. Thus, the electrical angle of the linear motor 1 and the advance direction of the linear motor 1 can be detected. The first magnetic detecting unit 14 outputs the scale head. The analog signals da and db of the two-phase sine wave of the address information of the current position information of 18 are the most suitable for the first magnetic detecting unit 14 to convert the magnetic linear type into the electric number. Further, in the magnetic linear encoder i6, the magnetic characteristic sharp change portion 3 (described later) of the magnetic linear encoder i6 is magnetically placed in the scale head 18 along the longitudinal direction of the armature. The characteristic acute position detecting unit 22 is used to determine the signal from the first magnetic detecting unit 以及4 and the signal from the second magnetic detecting unit 20. The second magnetic detecting unit 20 is attached. The moving direction of the linear motor 1 is set to the first magnetic detecting portion 14 The phase shifted electrical angle! 8〇, the pitch scale corresponding to 1/2 the wavelength Lp). The analog signal dc of the sine wave is output from the second magnetic detecting unit. As the second magnetic detecting unit 2, a Hall element capable of converting a magnetic linear type into an electric signal is most suitable. The magnetic characteristic sudden change position detecting unit 22 is, for example, the output signal dc of the second magnetic detecting unit 20 and the first magnetic detecting unit 14 (see FIG. 6) in which the Lp/2 wavelength portion and the positional shift are added. The output signal da addition circuit (not shown), and the comparison of the magnetic characteristics change position by the addition result are reported? (not shown). As shown in Fig. 4, the analog signals da and db output from the two first magnetic detecting portions and the waveform of the analog signal dc output from the second magnetic detecting portion 20 are shown along the yoke 4. In Fig. 4, the vertical axis direction indicates the magnetic --16-200908536 density ΒΓ, the horizontal axis direction indicates the position of the scale head 丨8, and the vertical axis direction indicates the effective magnetic flux from the position of the permanent magnetic _8 column. Magnetic flux density Br. Further, as shown in Fig. 7(a), the waveforms of the classifying signals d a and d b outputted from the i-th magnetic detecting unit 14 around the origin are enlarged. Next, a description will be given of a drive system 50 for a linear motor unit according to an embodiment of the present invention. The figure is a block diagram showing a configuration example of the drive system. As shown in Fig. 10, the drive system 5 is a fixed drive unit such as a motor drive control device (auxiliary drive) 30, a magnetic characteristic sudden change position detecting unit 2, a position information converter 28, and a writable memory. 3丨 constitutes. The position information converter 28 that converts the analog signals da, db' of the two-phase sine wave output from the first magnetic detecting portion 14 into the position data, and the position command indicated by the external line motor 丨 are connected (Fig. The motor drive control device 30 that calculates the current command to the armature coil 12 is calculated from the signal P 〇 s ' of the current position of the scale head 18 obtained by the position information converter 28. The motor drive control device (servo drive) 3 is constituted by, for example, a central calculation device (or a microprocessor), a ROM, a RAM, an input/output circuit, and a volt amplifier. The line-driven motor i is driven while controlling the current flowing into the coil based on the magnetic signal from the first magnetic detecting unit 14. The position information converter 28 inputs an analog signal indicating the current position of the movable member 1 读取 read by the scale head 18 attached to the end portion of the armature coil 12, that is, by the first magnetic detecting portion 14 The analog signal da, db of the output two-phase sine wave is transformed into position data. The position information transducer 28-17-200908536 is a position transducer 'and is also a position counter indicating the current position of the scale head 18. The position information converter 28 receives the reset signal output from the motor drive control unit 30 when the return to the origin is completed, and the position counter is zero. The motor drive control device 30' calculates the current command based on the information pos of the current position of the scale head 18, and controls the target current and the moving speed of the movable member by supplying the control current to the movable member via a feed wire (not shown). Further, in the above description, the position information converter 28 is independently constituted as one of the components of the drive system 50, but is not limited thereto, and may be disposed inside the magnetic linear encoder 16. The magnetic linear encoder 16 can also be used as one of the components of the motor drive control device 30, and is disposed inside. Further, conversely, the motor drive control device 30 may be provided as one of the components of the magnetic linear encoder 16 and disposed therein. The magnetic characteristic sudden change position detecting unit 22 outputs the analog signal da outputted from the first magnetic detecting unit 14 and the analog signal dc outputted from the second magnetic detecting unit 20 to add and calculate the two signals. The analog signal d a and the analog signal d c have a phase offset of 180 degrees, which is a relationship between d a and dc. Therefore, if the two are added together, they cancel each other out, and when the permanent magnet 8 is closely attached, the magnitude of the addition signal ac is close to zero. It is not zero because of the magnetic characteristics and shape of each of the permanent magnets 8, and the first magnetic detecting unit 14 and the second magnetic detecting unit 20 have errors. Further, the magnitude (" of the addition signal ac" is processed (e.g., threshold 値 processing) to detect a sharp change in the magnetic characteristics. Moreover, da+ dc becomes a larger output signal due to the disintegration of the relationship between da and dc at the magnetic characteristic -18-200908536. As shown in Fig. 5', the addition signal, i.e., the composite sensor output, has not changed over the entire range of the magnetic light 4. Further, as shown in Fig. 7, (a) ', the waveform of the addition signal ac around the origin is enlarged. In response to the threshold processing described above, the magnetic characteristic sudden position detecting unit 22' outputs the magnetic characteristic sharp position detecting signal dth and the over-signal do v to the motor drive control device 3A. Further, the above-described threshold 値 processing can be appropriately set in accordance with the accuracy required for the transport device to which the linear motor is applied. Further, the magnetic characteristic sharp position detecting unit 2 2 may be disposed as one of the components of the magnetic linear encoder 16 and disposed therein. Further, since the magnetic linear encoder 16 can be disposed as one of the components constituting the motor drive control device 30, the magnetic characteristic sudden position detecting unit 2 2 can be disposed in the motor drive control device 3 〇 internal. In the linear motor according to the embodiment of the present invention, as shown in Fig. 3, the magnetic characteristic sharp portion 32 is provided as a part of the yoke 4 at both end portions of the plurality of permanent magnets 8 in close contact with each other. In addition, in the third figure, the magnetic characteristic sudden change unit 3 2 provided at the left end is used for detecting the position of the origin of the linear motor by the magnetic characteristic sudden change unit 3 provided at the right end. The magnetic characteristic sharp portion 32 is composed of a non-magnetic material or a magnetic body. Further, a material having a magnetic permeability of r 5 or more is preferable, and a material having a relative magnetic permeability of r 1 0 or more is more preferable, and a material having a relative magnetic permeability of r 1 〇 〇 〇 〇 or more is most suitable. -19- 200908536 Further, as a material of the magnetic characteristic sharp portion 3 2 , for example, an alloy, a copper alloy, or a non-magnetic stainless steel (for example, SUS 3 04 ) material. Further, the magnetic material having a high relative magnetic permeability is made of magnetic stainless steel, mild steel, neodymium iron BF Μ, carbon steel or a thickness (length) of a linear motor direction in which the magnetic characteristic sharp portion 32 can be applied, compared to a permanent magnet. The magnetization of 8 is also short, but the application is longer than the magnetization direction of the permanent magnet 8. The characteristic change position which is stabilized by the magnetic characteristic rapid change position detecting unit 22 is suddenly changed. The magnetic property sharp portion 3 2 has an outer diameter that is substantially the same as the inner diameter of the cylinder, and is applied to the outer peripheral portion by press-fitting one end of the cylindrical member 6, and is preferably fixed by caulking or the solid member 6. It is assumed that the magnetic characteristics are not disposed at the ends of the permanent magnets 8 rows, and when the voids are formed, the magnetic fluxes present at the ends are immediately returned to the different poles of the permanent magnets 8 themselves. On the other hand, in the case where the permanent magnet 8 is provided with the magnetic characteristic sudden change portion 32, the opposite end of the permanent body which passes through the magnetic characteristic sudden change portion 32 and returns to the end portion appears. Further, if the relative magnetic permeability of the material of the magnetic characteristic sharp portion 3 2 is drawn, the magnetic flux appearing at the end portion is drawn, and the magnetic detector is generated for the magnetic flux orthogonal thereto. In other words, the arrangement of the permanent magnets 8 and the magnetic portion 32 shown in Fig. 3 and the combined sensor output shown in Fig. 5 can be made of non-magnetic such as aluminum or the like, and more preferably carbon steel. When the length of the moving direction of 1 is longer, after the magnetic member 6 is detected, the magnetic flux is connected from the end of the end portion of the cylindrical sharp portion 3, and the magnet 8 is a relatively large and relatively large reverse. The characteristic change B ac wave -20- 200908536 The shape can be understood 'According to the movement command of the movable member 10, the moving direction X and the output signal of the composite sensor output ac are monitored on both sides, thereby generating the excess of the movable element 1 The situation can be checked. In the left end or the right end of the permanent magnet 8 column shown in Fig. 3, the case where the movable member 1 超出 is exceeded is generated. As shown in Fig. 5, it is understood that the output of the combined sensor output ac is rapidly increased. Then, by changing the magnetic characteristic sharpness position detecting portion 22, the output of the threshold 値 processing synthesis sensor output ac is larger than the state in which the predetermined size changes, whereby the over state of the movable member 10 can be detected. The threshold 値 process here can be appropriately set, for example, in accordance with the accuracy required for the transport device to which the linear motor is applied. In the normal operation control, the movable member 1〇 moves in the right direction at the right end of the third figure, and the magnetic characteristic sharpness position detecting unit 22 detects the right end shown in FIG. 5 by the threshold 値 process. In the case of the position χ4, the position x4 can be applied to the inspection of the right end of the movable member 10 beyond. By the same processing, in the normal operation control, the movable member 1 移动 moves in the left direction at the left end of the third figure, and when the origin setting reference position X 1 (described later) is detected by the threshold 値 process, This position is applied to the inspection of the left end of the movable member 1 超出. As shown in Fig. 3 and Fig. 6, as the magnetic characteristic sharp portion 32, the curve ga in Fig. 1 indicates the use of the middle of the diameter of the cylindrical member 6 which is substantially the same size as the permanent magnet 8. The addition signal ac of the analog signal of the solid non-magnetic stainless steel SUS 3 0 4 (relative magnetic permeability 1. 〇0 0 8 ). In Fig. 1, the 'horizontal axis indicates the position of the scale head' and the vertical axis indicates the size of the composite sensor output signal. -21 - 200908536 Here, a modification of the magnetic characteristic sharpening portion will be described. The magnetic characteristic sharp portion 32b shown in Fig. 3 is a high relative magnetic permeability magnetic body 3 having a relative magnetic permeability r = 1 0 0 0 0 in the axial center portion, and has a diameter of half of the permanent magnet 8 Size, using non-magnetic stainless steel (SUS3 04) 34 on the outside. The curve gb in Fig. 1 shows the addition signal ac of the analog signal when the magnetic characteristic sharp portion 3 2b is formed. Further, in the magnetic characteristic sharp portion 3 2c shown in Fig. 14, a high relative magnetic permeability magnetic body having a relative magnetic permeability r = 1 0000 is used, and the diameter thereof is the same as that of the permanent magnet 8. The curve gc in Fig. 1 1 shows the addition signal ac of the analog signal of this modification. It can be understood from the magnetic characteristic curve groups g a to g c shown in Fig. 1 that any material other than the non-magnetic material or the magnetic material can be used as the material of the magnetic characteristic sharp portion. According to the above, the magnetic property when the material of the magnetic characteristic sharpening portion is changed' is shown in Fig. 2 as a simulation result by the inventors. It is understood that at least the material containing the magnetic material having a relative magnetic permeability r of 50 or more is preferable, and a material containing a magnetic body having a relative magnetic permeability r of 1 〇〇 or more is preferably used. More preferably, it is more preferable to use a material containing a magnetic body having a relative magnetic permeability r of 1 Å or more. Further, the position of the magnetic characteristic sharp portion is not limited to the above-described embodiment. Of course, there are several variations. For example, it is not the end side of the magnet array, and a magnetic characteristic sharp portion can be disposed in the middle of the yoke. Further, in the middle of the end portion of the magnet array and the yoke, a magnetic characteristic sudden change portion may be disposed at a plurality of points -22-200908536 <Home position setting and origin setting operation> Next, the origin setting and the origin setting operation of the line motor configured as described above will be described. In the normal state, the position information converter 28 is used to calculate the current position of the mover 10. Further, when the power source is OFF and restarted, the movable member 10 is taken out from the bottom 2, and then the movable member 10 is attached to the bottom portion 2 again, and the absolute position of the movable member 10 cannot be calculated. In the position information converter 2, the reference position for calculating the absolute position is shifted. Therefore, in the linear motor according to the present embodiment, the home position return operation to be determined by setting the reference position again can be automatically performed without passing through the operator. Figs. 15 to 18 are flowcharts showing the flow of the origin setting of the linear motor 1 of the present embodiment. Since the method of setting the origin by the origin setting differs depending on the positional relationship between the movable member 10 and the magnetic characteristic sudden change unit 32, it is described in various cases. Fig. 15 is a flow chart showing the origin setting when the movable member 10 passes through the origin in the direction of the magnetic characteristic sharp portion 3 2 before returning to the origin. Furthermore, it is assumed that the origin is at the position shown in Fig. 15. First, an operation panel (not shown) provided in the motor drive control device 30 outputs a return home command to the motor drive control device 30 by a manual command or a program command in the linear motor operation program. S 1 0 1 ) ° Next, the control means of the microprocessor or the like in the motor drive control device 30 is the magnetic characteristic sudden change position detecting unit 22 detecting the magnetic characteristic sudden change portion 3 2 'detecting the movable member 1 〇 along the magnetic characteristics The sharp change portion 3 2 passes through the -23-200908536 origin (step S 1 0 2 ). In the present embodiment, the magnetic characteristic sharp portion 32 is a structure that also serves as an end detecting portion for detecting the end portion of the linear motor 1. Next, the sequence program for setting the origin of the memory in advance is executed, and the movable member 10 of the linear motor 1 is moved in the direction close to the origin, and the origin is passed, thereby causing the movable member 1 to move away from the origin. In the direction, only the predetermined distance is moved (step S103). Remove the origin position shown in Figure 15. Here, as a predetermined distance, for example, a 1-to-scale pitch of a magnetic linear scale, for example, a distance equivalent to a three-scale pitch is most suitable. It is sufficient to remove the distance from the origin. Further, the linear motor 1 is driven at a low speed in the origin direction to move the movable member 1 〇 along the origin direction, and is processed by the magnetic characteristic sharp position detecting unit 22 (for example, threshold 値 processing) from the second magnetic detecting unit 20 The output signal ac of the analog signal between the two points of the distance of 1 / 2 scale interval (Lp/2) is output, and the magnetic characteristic sharp position is searched (step S104). The addition signal here is a signal with a phase different from each other by 180 degrees to calculate the difference in magnetic characteristics between the two points. Next, the 値Vb of the addition result is larger than the position of the predetermined 値, and the reference position X1 is set as the origin (step S1 0 5 ). In this manner, the origin setting reference position X 1 can be detected by the magnetic characteristic sudden change position detecting unit 2 2 '. The origin setting reference position x 1 ' is not deviated from the boundary between the magnetic characteristic sharp portion 3 2 and the permanent magnet 8. This is for the following reasons. That is, since the vicinity of the boundary between the magnetic characteristic sharp portion 3 2 and the permanent magnet 8 is the peak of the waveform ac, the position thereof can be X1. However, the 値 値 will have errors due to the various -24 - 200908536 yokes. Therefore, when the threshold 値 is set as represented by the peak 某一 of a certain yoke, it is possible that the other magnetic whip may fail to reach the threshold 因 due to an error. Therefore, it is most suitable to use the vicinity of the middle portion of the waveform ac as the threshold ,, and it is most suitable to shift the magnetic characteristic sharp portion 3 2 and the vicinity of the boundary of the permanent magnet 8 by X 1 . <About the predetermined 値> Here, the predetermined 値 can be set as follows. First, the in-line type motor 1 has an error in each size of the permanent magnet 8 to be used, an error in the magnetic characteristics when the permanent magnet 8 is magnetized, and a permanent magnet which is generated when the permanent magnet 8 is inserted into the assembly of the cylindrical member 6. Fixed position error. In consideration of the above-mentioned errors, the two analogies output from the first magnetic detector 14 and the second magnetic detecting unit 20 are observed in the range of movement of the both ends of the permanent magnets 8 arranged in a line and the movement range around the origin. The variation of the sum signal of the signals da and dc is as large as 5% of the Vb, that is, the fixed value of 1.05 Vb can be utilized. According to the experiment conducted by the person, etc., as long as it is 値=1.1 Vb which is 10% larger than the variation width Vb of the addition signal ac, the origin can be set more stably as long as it is wider than the addition signal ac of the two analog signals. Vb is 25% larger than . 1 . 2 5 V b is better. When the origin setting reference position X1 is determined, the movable member 10 is decelerated by the deceleration determined in advance from the X1, and the position at which the movable member 10 stops is the position χ2 of the scale head (refer to Fig. 7(b), Figure 7 (C)). This deceleration is most suitable, for example, as a control means for setting a microprocessor or the like stored in the motor drive control device 30 in advance. In addition, if the deceleration is large, an excessive overshoot occurs when the movable member of x2 stops, and there is a flaw between -25-200908536 and the end of the field yoke. Further, if the deceleration is too small, the arrival is that the deceleration stopped in the yoke is an appropriate enthalpy. Next, the movable member 1 使 is reversed from the current position § of the scale head (step S106). For the A-phase signal da and the B-phase signal db of the two-phase sine wave analog signal of the stop position x2, use ^ to calculate the position xh of the scale head. X h (Lp/27i)f(db/da) (1) However, in the formula (1), f(db / da) is defined as the following formula (1 d ). f(db/da)= atan(db/da)-7t/2|dag〇,db2〇 f(db/da)= atan(db/da) + 7i/2|da <0,db 2 Ο f(db/da)= at an (db / d a)+ π/2 I d a <0,db < Ο ·· f(db/da)= a t an (db/d a) - π/2 I d a ^ 0 , d b < 0 ·· The stop position x2 of the mover 10 is the obtained target hp A. In the case of zer 〇 in Fig. 7(a) or Fig. 7(c), the following is formed. The column table; x2 = -xh ·· (2) is roughly equal to xh of the above formula (1). Furthermore, it is effective in the range of 1^8±scale spacing/2. The movable member 10 moves at a slight speed from the current position X 2 along the seventh picture (the opposite direction from the current direction), and repeats the search for the polarity change point of the two-phase sine wave analog signal (the step time is increased. [x2 let the moving square number The magnetic formula = (1) The formula (1 a ) ... (la) ... (lb) . (lc) • (Id) The origin of the head is 0 on the X-axis ( In the right direction of the position meter (b), the equation (1), step S 1 0 7 ). -26- 200908536 reaches the polarity change point of the mover 10, that is, the position of xkO (Fig. 7(c) ' Position of χ3' stops the movable position 1〇 and resets the current position counter of the scale head (step S 1 0 8 ). Furthermore, in the above formula (1), the original head of the obtained scale head The point position hpA is 〇 (zero) in the X-axis, but the position is changed to any position of the waveform which is not shown in Figure 7 (a), and the definition is changed. Of course, the formula (la) to (Id) of "π" In the case where each of the permanent magnets 8 has a dimensional error or an error in magnetization characteristics, in order to solve the influence of the errors, the obtained origin position ph can be obtained. A. The correction is performed. The method of the correction is not the gist of the present invention, so it will not be described in detail here. In the present embodiment, when the assembly operation of the linear motor 1 is completed, the operator can be used without When the origin x3=phA of the reference position (dot) of the absolute position of the linear motor 1 is realized, the origin setting processing can be automatically realized. Therefore, as in the past, the operator does not need to perform the additional operation for the origin setting. Next, Fig. 16 shows the flow of the origin setting when the movable element 10 is not at the position of the magnetic characteristic sudden change unit 32 before returning to the origin. In the case of such a positional relationship, it is movable. The sub-10 moves beyond the origin position, moves to the magnetic characteristic sudden change unit 32, and moves again toward the origin position. First, the motor drive control device 30 outputs a return-to-origin command by a program command in the linear motor operation program ( Step S20 1 ). Next, the linear motor 1 is driven in the origin direction to move the movable element 1 〇 along the origin direction, and the magnetic characteristic sharp position detecting unit 22 is used -27- 2009085 36 processing (for example, threshold 値 processing) searches for the magnetic characteristic sharp change position from the addition signal ac ' of the analog signal between the two points of the distance 1/2 scale interval (Lp/2) output from the second magnetic detecting unit 2 (step S2〇) 2) Next, 'the change width vb of the addition result is larger than the position of the predetermined ,, and the reference position x1 is set as the origin (step S2〇3). When it is determined that the reference position χ 1 is set to the origin, the mover 1 使 is made X 1 starts to decelerate and stops at the scale head position χ 2. Secondly, 'moving the movable member 10 from the current position χ2 of the scale head in the origin direction (the opposite direction from the current direction) at a slight speed (step s 2 04 ), The equation (1) on the calculus is used to find the polarity change point of the two-phase sine wave analog signal (step S 2 0 5 ). When the mover 1 〇 reaches the polarity change point, the mover 1 〇 is stopped, and the current position counter is reset (step S206). Next, the "Fig. 17" shows the flow of the origin setting when the magnetic characteristic sharp portion 3 2 is in the middle of the yoke and disposed closer to the inner side than the origin position. In the case of such a positional relationship, the movable member 1 移动 moves beyond the magnetic characteristic sudden change portion 32 located in the middle of the yoke until it moves to the origin position. First, the home drive command is output to the motor drive control device 30 by the program command in the line motor operation program (step S301). Then, the linear motor 1 is driven in the origin direction to move the movable member 1 〇 along the origin direction, and is processed by the magnetic characteristic sharp position detecting unit 2 (for example, threshold 値 processing) from the second magnetic detecting unit 2 0 . The output signal is an addition signal ac -28-200908536 of the analog signal between the two points of the distance of 1 / 2 scale interval (Lp/2), and the magnetic characteristic sharp change position is sought (step S3 02). Next, the variation width Vb of the addition result is larger than the position of the predetermined 値, and the reference position χΐ is set as the origin (step S3 03). When the home position setting reference position X1 is set, the movable member 10 is moved from the current position X1 of the scale head at a slight speed in the origin direction to calculate the polarity change point of the two-phase sine wave analog signal. (Step S 3 0 4 ). When the mover 10 reaches the polarity change point, the mover 1 〇 is stopped > the current position counter is reset (step S 3 0 5 ). Next, Fig. 18 shows a flow of the origin setting when the magnetic characteristic sharp portion 3 2 is placed in the middle of the yoke and is disposed closer to the outer side than the origin position. In the case of such a positional relationship, the movable member 1 移动 moves beyond the origin, and the moving direction is changed at the position of the magnetic characteristic sharp portion 3 2 disposed in the middle of the yoke until moving to the origin position. . First, the home drive command is output to the motor drive control device 30 by the program command in the line motor operation program (step S4〇1). The linear motor 1 is driven in the origin direction to move the movable member 1 〇 along the origin direction. The distance output from the second magnetic detecting unit 20 by the magnetic characteristic sharp position detecting unit 22 (for example, threshold 値 processing) \丨2 The addition signal ac of the analog signal between the two points of the scale interval (Lp/2) searches for the magnetic characteristic sharp change position (step S 4 0 2 ). Next, the change width Vb of the addition result is larger than the position of the predetermined 値, and the reference position X 1 is set as the origin (step s 4 0 3 ). When the reference position X1 is set as the origin, the movable member 1 减速 is decelerated from the -29-200908536 X 1 and stopped at the scale head position X2. Next, the movable member 10 is moved at a slight speed from the current position Χ2 direction of the scale head (the direction opposite to the current direction) (the equation (1) is calculated in the above step, and the two-phase sine wave analog signal point is searched (step S405). When the sub 1 〇 reaches the polarity change point, the mover is reset to the current position counter (step S 406 ). Further, the origin hpA of the reference position (point) at the absolute position of the set line in any of the above-described outer casings. When the light-emitting means such as the LED is turned on for a predetermined period of time, or when the sound absorbing means of the bee audible frequency is operated to notify the external notification means of the magnetic linear encoder 16 , it is suitable to be completed by the operation origin setting processing. <Modifications> In the above-described origin setting, a low speed which decelerates near the origin is used, and a calculation method of the return distance which is extremely distant from the position X2 in the range where the origin setting error is extremely small is maintained. In addition, in the example of (a), the two-phase sine wave is analogous to the A-phase signal d a db, and the position where the polarity is changed from positive to negative (or negatively positive) is determined. Further, after the magnetic property sharp change position detecting unit 22 sets the reference position x1, the reset position information converter 28 sets the reference position x 1 to the origin and uses the 'positional accuracy slightly along the origin S404. 1 0 stop, type motor 1, can make the sounder, etc., attached to the staff to confirm that it is very small to grasp first. Also in the 7th or B phase signal can complete the detection origin, the original point is thick, or -30 - 200908536 Adopted in full use. According to the present embodiment, in order to calculate the origin setting of the absolute position of the linear motor, it is not necessary to have an artificial work, that is, attaching, adjusting, and setting the limit switch or the lock spring. When the assembly of the linear motor is completed, the assembly and installation work of the origin setting relationship are all completed at the same time. Further, according to the magnetic field distribution around the permanent magnet of the linear motor and the magnetic field characteristics, the magnetic characteristics can be automatically checked for rapid change, and the origin setting can be easily and accurately performed. In other words, when the origin is set, the operator is not required, and the error of the origin setting operation of the operator's ability can be eliminated, and the origin of the linear motor with good reproducibility and stability can be set. In addition, the present invention is not limited to the above-described embodiments, and modifications may be made and constituent elements may be embodied in the scope of the invention without departing from the spirit and scope of the invention. Further, various inventions can be formed by appropriate combination of a plurality of constituent elements disclosed in the above embodiments. For example, several constituent elements may be eliminated from all the constituent elements shown in the embodiment. Further, constituent elements of different embodiments may be combined as appropriate. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a front elevational view showing a schematic configuration of a linear motor according to a first embodiment. Fig. 2 is a cross-sectional view taken along line A-A in Fig. 1. Fig. 3 is a side elevational view of the linear motor of the first embodiment. -31 - 200908536 Fig. 4 is an output waveform of the first magnetic detecting portion according to the first embodiment. Fig. 5 is a waveform obtained by adding the output of the second magnetic detecting portion of the first embodiment. Fig. 6 is a partially enlarged view showing the vicinity of the origin of the linear motor of the first embodiment. Fig. 7(a) is a partially enlarged view showing an output waveform of the first magnetic detecting unit in Fig. 6, and Fig. 7(b) is a reference view showing an operation command for the movable member at the time of setting the origin. Fig. 8 is a view showing a simulation result of a combined magnetic field when the same-pole magnets face each other and are in close contact with each other. Fig. 9 is a view showing a simulation result of a combined magnetic field when a homopolar magnet is brought into close contact with each other and a cylindrical member having a high relative magnetic permeability is used. Fig. 1 is a view showing a line type according to an embodiment of the present invention. A block diagram of a configuration example of a drive system of a motor. Fig. 1 is a view showing the output of the composite sensor which changes in accordance with the relative magnetic permeability. Fig. 1 is a view showing simulation results performed on the composite sensor output that changes in accordance with the relative magnetic permeability. Fig. 1 is a view showing another structural example of the magnetic characteristic sharp portion of the present invention. Fig. 14 is a view showing another example of the structure - 32 - 200908536 of the magnetic characteristic sharp portion of the present invention. Fig. 15 is a flow chart showing the flow of the origin setting of the linear motor of the embodiment. Fig. 16 is a flow chart showing the flow of the origin setting of the linear motor of the embodiment. Fig. 17 is a flow chart showing the flow of the origin setting of the linear motor of the embodiment. Fig. 18 is a flow chart showing the flow of the origin setting of the linear motor of the embodiment. [Description of main component symbols] 1 : Linear motor 4 : Magnetic car 6 '· Cylindrical member 8 : Permanent magnet 1 0 : Movable member 1 2 : Armature coil 1 4, 2 0 : Magnetic detecting unit 1 6 : Magnetic Linear encoder 18: scale head 1 9 : magnetic scale portion 22: magnetic characteristic sharp position detecting portion 2 8 : position information converter 3 0 : motor drive control device - 33 - 200908536 3 2 2 b, 3 2 C : Magnetic characteristic sudden change part 5 0 : Drive system -34-