410182 A7 _；_B7_ 五、發明說明（1 ) 【發明所鼷之技術領域】 <請先閲讀背面之注意事項再填窝本頁> 本發明係關於自動進刀控制裝置，尤其適用於穿孔機 較佳之電鑽機之自動進刀控制裝置^ 【先行技術】 習知，就有使用由台架所支持之電鑽機，例如工字鋼 等被加工物，進行穿設螺拴孔等貫通孔。這種穿孔機，係 例如日本實公平6 _ 4 7 6 1 0號公報所揭示之穿孔機， 進行如下動作。 亦即，當起動該穿孔機時，首先設於穿孔機底部之電 磁基座之電磁鐵就激磁，該電磁基座就被磁性地吸引於被 加工物之表面。其後，就驅動上述電鑽機之驅動馬達與進 刀馬達。藉此，電鎭機雖然會高速迴轉，但是，進刀馬達 之迴轉爲不會傳達於傳動軸，不進行電鑽機之進刀。 經濟部智慧財產局貝工消费合作社印製 接著，操作手動手柄，卡入傳動軸之離合器時，電鑽 機由上述進刀馬達以低速自動地下降，不久，設於電鑽機 之鑽刀之先端爲達到被加工物之表面，而稍爲咬入於該表 面。於是•該鑽刀就受到來自被加工物之阻力，驅動該鑽 刀之電鑽機之驅動馬達之負載將會稍爲變大。此時之負載 變化將由負載感測器所檢測"當負載感測器檢測出該負載 之變化時，進刀馬達就被增速運動，而進行對於被加工物 之鑽孔。不久，上述鑽刀之先端就鑽穿過被加工物之下面 ，結束被加工物之鑽孔時，電鑽機之驅動馬達之負載就變 小，而檢測出鑽孔已結束。當檢測出該鑽孔時，不僅逆轉 本紙張尺度適用中國因家標準（CNS>A4規袼<210 * 297公釐） -4- 410182 a? _B7 五、發明說明（2 ) 上述進刀馬達之迴轉，並且，其迴轉速度變成更大，而從 被加工物後退。 (請先《讀背面之注意事項再填寫本頁) 按，有關本發明之其他先行技術，例如有曰本特開昭 61 -131807號公報所揭示者。 【發明所欲解決之問題】 上述之先行技術係如上述，設於電鑽機之進刀將咬入 於被加工物表面時之負載變化由負載感測器檢測，但是， 該負載之變化係依進刀之大小而異，又相同電鑽機之無負 載電流也具個體差，具有不能以良好精度檢測該負載變化 之問題。 本發明之目的，係提供一種可除去上述先行技術之問 題，將設於電鑽機之進刀咬入於被加工物表面時之負載變 化毫無個體差地以良好精度檢測之自動進刀控制裝置。又 ，其他目的，係提供一種進刀鑽孔被加工物之後時之負載 變化以良好精度檢測出來。 【解決問題之手段】 經濟部智慧財產局員工消费合作社印製 爲了達成上述目的，本發明係將電鑽機向被加工物自 動進刀之自動進刀控制裝置，其第1特徵爲具備：檢測無 負載迴轉時之電鑽機電流値之手段，與無負載迴轉時之電 鑽機電流値，將設於該電鑽機之鑽刀咬入於被加工物表面 時所增加之電流値以下之電流値作爲偏壓電流加算來求取 第1閾値之手段，與上述電鑽機電流値變成該第1閾値以 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） -5- Α7 410ίδ2 ____Β7___ 五、發明說明（3 ) 上時，判斷爲鑽刀已咬入於被力卩工物之手段。 若依據此特徵，就將無負載迴轉時之電鑽機電流値作 爲基礎來求取上述第1閾値，當電鑽機電流値變成該第1 閱値以上時，就判斷爲鑽刀已咬入於被加工物表面，所以 ，可將電鑽機之每個體之無負載迴轉時之電鑽機電流値爲 基礎作爲決定該第1閩値，其結果，就沒有電鑽機之個體 差，而可判斷鑽刀已咬入於被加工物表面》 又，本發明之第2特徵爲：設定較電鑽機之無負載迴 轉時之正常鑽機電流値更大之第2閾値，當上述鑽刀晈入 於上述被加工物表面之後電鑽機電流値爲變成該第2閾値 以下時，具有有判斷爲鑽刀爲已結束被加工物之鑽孔之手 段。依據此特徵時就可提高判斷鑽刀結束鑽孔時之精度。 【發明之實施形態】 茲參照.圖面詳細說明本發明。第2圖係表示鑽孔機之 全體構成之斜視圖》第3圖係表示右側側面圖。 在鑽孔機本體1下端，係於其內部形成有備有電磁鐵 MG之電磁基座2。在該鑽孔機本體1上部側面，設有沿 著該側面可上下移動之滑動板3 6，在該滑動板3 6支持 有電鑽機3。在該鑽孔機本體1內，設有使上述滑動板 3 6上下移動所需要之進刀馬達4，由該進刀馬達4所迴 轉驅動之傳動軸，設有離合器。3支手柄39，39， 39 ，係經由該離合器安裝於鑽孔機本體1 ，拆下該離合 器之狀態下當轉動該3支手柄時，就以手動，將電鑽機3 本紙張尺度適用中國國家標準（CNS)A4規格（210* 297公；8Π (請先閱讀背面之注意事項再填寫本頁) i 裝 ----Γ 訂 i.l· ! ----線 經濟部智慧財產局負工消费合作社印製 -6- 410182 a? ___B7_ 五、發明說明（4 ) 對於被加工物前進或後退。 (請先W讀背面之注項再填寫本頁) 又，在上述滑動板_ 3 6背側，形成有向上下具有傾斜 面之凹部（沒有圖示）。該滑動板3 6之凹部，係隨著上 述電鑽機3之下降而移動，當設於電鑽機3之鑽刀進給到 鑽刀尖時，就會作用於限制開關（沒有圖示）。 在上述電鑽機3，係具有由沒有圖示之驅動馬達所迴 轉之環狀鑽刀5，該鑽刀5係在電鑽機3下端之心軸1 1 先端向下裝設°上述心軸1 1係由從上述鑽孔機本體1下 端部向側方突出之托架1 2支持成可上下移動》又，在上 述鑽刀5內，滑動自如地設有中心銷5 a。 設於上述鑽孔機本體1正面之開關鈕（switch knob ) 經濟部智慧財產局員工消費合作社印製 4 0係用來操作起動開關6者，其係成爲2階段移動，將 該起動開關6之3個接點6A，6B，6C，以既定之順 序接通。例如，於後述之第1圖之電路圖，最初閉合接點 6A與6C，接著閉合接點6C與6B。因此，當操作開 關鈕4 0時，首先設於上述電磁基座2內部之電磁鐵MG 就被激磁而鑽孔機本體1就固定於被加工物，接著，就開 始驅動進刀馬達4與驅動馬達。按，卡入設於上述傳動軸 之離合器時，電鑽機3就與上述進刀馬達4連接，而進行 自動進刀。茲參照第1圖，說明本發明之驅動部之機能如 下。第1圖係用來說明該驅動部機能之電路圖。鑽孔機本 體1爲置於被加工物之既定位置，當操作上述開關鈕4 0 時，首先，起動開關6之接點6 A就閉合。其結果，設於 上述電磁基座2內部之電磁鐵MG就被激磁而鑽孔機1就 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公« ) A7 410182 ___B7 五、發明說明（5) 固定於被加工物。接著，當接點6 B與6 C閉合時，就驅 動電鑽機3之驅動馬達5 2，而驅動經由整流器5 3所連 接之進刀馬達4。在驅動馬達5 2之電通路，設有電流檢 測用變壓器5 4，而施加於驅動馬達5 2之負載變動就由 電流檢測用變壓器5 4成爲電流變化被檢測出來。由該電 流檢測用變壓器5 4所檢測之檢測電流係由整流器5 5所 整流’而由電阻5 6，電容器5 7所構成之平滑電路所平 滑而ίϊ入於微電腦5 8 » 如上述開始驅動驅動馬達5 2與進刀馬達4之後，轉 動上述3支手柄39，39，39，將電鑽機3之鑽刀5 內之中心銷5 a下降到直到抵接於形成於非加工物表面之 站頭標誌（punching marker)位置時卡入上述離合器時， 電鑽機3就連接於上述進刀馬達4，而進行自動進刀。並 且’電鑽機3之鑽刀5咬入於被加工物表面施加於驅動馬 達5 2之負載發生變動時，此變動將變成由電流檢測用變 壓器5 4所檢測之檢測電流之變動輸入於微電腦5 8。 微電腦5 8係由後述依本發明之無負載電流檢測方法 ，當檢測該檢測電流之變動時，就控制光電三端雙向可控 砂開關元件TR 1 (photo· triode AC switch)之導通時間 ，亦即，控制相位，而輸出增速或減速運動進刀馬達4之 訊號。亦即，進刀馬達4係控制成較鑽刀5咬入於被加工 物表面爲止之當初速度，爲能夠變成更高速度迴轉之增速 或低速度迴轉之減速。其結果|電鑽機3係較當初之速度 爲更高速度或低速度進給，而由鑽刀5進行被加工物之鑽 本紙張尺度適用中國國家標準（CNS)A4規格（210*297公釐） (請先閲婧背面之注意事項再填寫本頁) --------I 訂---------- 經濟部智慧財產局具工消费合作社印製 -8- A7 410182 _B7__ 五、發明說明（6) 孔。 鑽孔作業中之負載變化，爲持續地由電流檢測用變壓 器5 4所監視，而反饋至進刀馬達4，進刀馬達4之迴轉 速度將被控制成適合負載之速度。按，萬一，當檢測超載 時，就由沒有圖示之電路’仍然激磁電磁基座2之電磁鐵 MG之狀態下停止驅動馬達5 2與進刀馬達4，不僅防止 各馬達之損傷’並且，又可防範鑽刀之迴轉慣性力致使鑽 孔機本體1爲將鑽刀5爲中心旋轉之危險於未然。 接著•鑽刀5先端穿過被加工物下面結束由該鑽刀5 之鑽孔時，電鑽機3之驅動馬達5 2之負載就變小。此負 載之變化係透過上述電流檢測用變壓器5 4而由微電腦 5 8檢測，啓動鑽孔結束時期檢測用繼電器X 1 >而切換 其接點XI’使進刀馬達4逆轉•並且，控制光電三端雙 向可控矽開關元件TR1來增速進刀馬達4之迴轉速度。 其結果，電鑽機3係以鑽孔作業中之進給速度以上之速度 ，從被加工物後退。 按，當上述鑽刀5咬入於被加工物接面時，及鑽刀5 先端穿越被加工物下面時之驅動馬達5 2負載之檢測’係 由上述微電腦5 8下列地進行。將其步驟，參照第4圖之 流程圖與第5圖之時間圖表說明如下。 於第5圖之時刻t1，閉合上述接點66Β與6C時 ，就在驅動馬達52開始流動鑽機電流i ’而電鑽機就開 始迴轉（步驟S1)。進到步驟S2時’微電腦58就設 定暫時性閾値電流a (數安倍程度），進到步驟S3就從 (請先W讀背面之注意事項再填寫本頁) ^-------I -^>—-1 11111· 經濟部智慧財產局員工消費合作社印製 本紙張尺度適用中國因家標準<CNS)A4規格（210 X 297公« > -9- 410182 A7 ._B7 五、發明說明（7 ) (請先Μ讀背面之法意事項再填寫本頁) 電流檢測用變壓器5 4檢測電鐄機電流i ，亦即，檢測流 動於驅動馬達52之電流i 。按•此暫時性閩値電流a係 假想加上電鑽機之偏差，電鑽機支持金屬件之加工精度等 時之最惡劣情況之電鑽機無負載時之電鑽機電流値。 由進刀馬達4所迴轉驅動設於傳動軸之離合器被Ο N ，當電鑽機3之鑽刀5向被加工物表面下降之時段就判斷 步驟S 4。亦即，判斷鑽機電流i是否已變成上述暫時性 閾値電流a以上。若在該步驟S 4之判斷爲肯定時，就進 到步驟S 5，而進行上述暫時性閾値電流a以上之鑽機電 流i是否經過t秒鐘之判斷，例如持續3秒鐘。若此判斷 爲肯定時，儘管電鑽機爲無負載由於已變成較上述暫時性 閾値電流a爲大之情形，所以判斷爲發生某些異常，而進 到步驟S 6發出超載警報》 經濟部智慧財產局員工消费合作社印製 另一方面，若上述步驟之判斷爲否定時，就進到步驟 S7，而設定最終閾値b (=鑽機電流i +偏壓値c)。 此偏壓値c ，係考慮電源電壓之變動，鑽刀5之直徑，被 加工物材質等時之隨著鑽孔所發生之鑽機電流之最小上升 値。接著，進到步驟S8，判斷上述鑽機電流i是否已到 上述最終間値b以上。若此判斷爲否定之時段，將表示電 鑽機之鑽刀5爲沒有達到被加工物表面。 按，若上述步驟8之判斷變成肯定時（第5圖之時刻 t 2 )，就進到步驟9，判斷是否經過t秒，例如經過3 秒。若變成肯定時，就判斷電鑕機之鑽刀5爲已咬入於被 加工物表面。於是，就進到步驟S10，微電腦58就進 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公麓） -10 - A7 410182 B7_ 五、發明說明（8) <請先Μ讀背面之注意事項再填寫本頁) 行光電三端雙向可控矽開關元件TR1 (參照第1圖）之 動作期間之相位控制，使進刀馬達4爲較鑽刀5咬入到被 加工物表面爲止之當初速度，能夠變成高速度迴轉加以增 速或低速度迴轉之減速。 接著，於步驟S 1 1 ，就替換爲最終閾値t)=上述暫 時性閾値a。於步驟S 1 2，就判斷是否成立，，鑽機電流 i差最終閾値b ，若此判斷爲肯定之時段，爲還在鑽孔作 業中1所以，對於驅動馬達5 2施加著大的負載當中。其 後，當於步驟S 1 2之判斷變成否定時（第5圖之t 3 ) ，就曉得上述鑽刀5已穿過被加工物背面，而進到步驟 SI 3，XI繼電器就通電。按，當鑽孔當中鑽屑若堵塞 於鑽刀之鑽屑逃逸溝時•即使鑽刀5穿過被加工物背面， 鑽機電流i仍如第5圖以一點鏈線d所示，不會變成太小 ，但是因如上述步驟S11其最終閾値b爲替換成暫時性 '閾値a，所以這種情形時也可精度良好地檢測鑽刀5已穿 過被加工物背面》 經濟部智慧財產局員工消费合作社印製 於步驟S 1 3，若X 1繼電器通電時，連接於進刀馬 達4之接點XI’就切換，而進刀馬達4會逆轉。其結果 ，電鑽機將被向上拉起。 由以上之說明就淸楚，若依據本發明，將各個鑽孔機 之無負載時之鑽機電流i爲基礎，只有既定之偏壓電流値 c *增加鑽機電流時，因會判斷爲鑽刀5已咬入於被加工 物，所以，鑽孔機個體有所偏差時，也可用良好精度檢測 該鑽刀之咬入時點* 本紙張尺度適用中國國家標準（CNS)A4規格<210 * 297公芨> • 11 - 經濟部智慧財產局員工消费合作社印5# A7 _____B7_____ 五、發明說明（9) 【發明效果】 若依據本發明申請專利範圍第1項之發明，因無負載 迴轉時之鑽機電流値係被視爲第1閾値之基礎，所以’可 將該第1閾値依各電鑽機之個體加以設定。所以，可用良 好精度檢測該鑽刀之咬入時點。 若依據本發明申請專利範圍第2項之發明，則可檢測 電鑽機之超載，來提升安全性。 若依據本發明申請專利範圍第3項之發明，作爲第2 閾値，設定爲較電鑽機無負載迴轉時之正常鑽機電流更大 之値，依據該第2閩値來判斷鑽刀已結束被加工物之鑽孔 ，所以即使鑽刀之鑽屑逃逸溝堵塞鑽屑而鑽機電流沒有降 低到電鑽機無負載迴轉時之正常鑽機電流程度時，也可檢 測鑽刀已結束被加工物之鑽孔。 若依據.本發明申請專利範圍第4項之發明，當判斷鑽 刀已咬入於被加工物表面時，會增速或減速進刀速度，所 以可用適合於鑽刀直徑之速度鑽孔，而可防止鑽刀之破損 或電鑽機或進刀馬達等之燒毀。. 圖式之簡單說明 第1圖係表示本發明之一實施形態構成之電路圖。 第2圖係本發明所適用之鑽孔機一例之斜視圖》 第3圖係第2圖之鑽孔機之右側側面圖。 第4圖係表示本發明要部機能之流程圖。 本纸張尺度適用中S國家標準（CNS)A4規格（210 X 297公t > ------ ------裝 ------T 訂··'--— l· — !線 I <請先閱讀背面之注意事項再填寫本頁) -12- A7 410182 _B7_ 五、發明說明（10) 第5圖係用來說明本發明要部動作之時圖圖表。 【符號之說明】 1…鑽孔機本體，2…電磁基座，3…電鑽機，4…進刀 馬達，5…鑽刀，6…起動開關，6 A，6 B，6 C…接 點，5 2…驅動馬達，5 4…電流檢測用變壓器，5 8… 微電腦，X 1…繼電器，T R 1…光電三端雙向可控矽開 關元件。 ----!^--------訂--/----^---'線 . (請先閱讀背面之注意事項再填寫本頁) 經濟部智慧財產局貝工消費合作社印製 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐〉 -13-410182 A7 _; _B7_ V. Description of the invention (1) [Technical Field of the Invention] < Please read the precautions on the back before filling this page > The present invention relates to an automatic feed control device, especially suitable for perforation Automatic feed control device for electric drill with better machine ^ [prior art] It is known that there is a through-hole such as a screw hole and a through-hole such as a machined object supported by a stand, such as an I-beam. Such a punching machine is, for example, the punching machine disclosed in Japanese Patent Publication No. 6_4677-110, and performs the following operations. That is, when the puncher is started, the electromagnet of the electromagnetic base provided at the bottom of the puncher is excited first, and the electromagnetic base is magnetically attracted to the surface of the workpiece. Thereafter, the drive motor and the feed motor of the electric drill are driven. As a result, although the electric hammer can rotate at a high speed, the rotation of the feed motor is not transmitted to the drive shaft, and the feed of the electric drill is not performed. Printed by Shelley Consumer Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs. Then, when the manual handle is operated and the clutch of the drive shaft is engaged, the electric drill is automatically lowered by the above-mentioned feed motor at a low speed. It reaches the surface of the workpiece and bites into the surface slightly. Thus • The drill is subject to resistance from the workpiece, and the load of the drive motor of the electric drill that drives the drill will become slightly larger. The load change at this time will be detected by the load sensor. "When the load sensor detects the load change, the feed motor will be moved at an increased speed to drill the workpiece. Soon, the tip of the aforesaid drill bit was drilled under the workpiece, and when the drilling of the workpiece was finished, the load of the driving motor of the electric drill was reduced, and it was detected that the drilling had ended. When this hole is detected, it will not only reverse the paper size and apply Chinese standards (CNS > A4 Regulations < 210 * 297mm) -4- 410182 a? _B7 V. Description of the invention (2) The above feed motor The turning speed is also increased, and the turning speed is reversed from the workpiece. (Please read "Notes on the back side before filling out this page.") Press, and other prior arts related to the present invention are disclosed in, for example, Japanese Patent Application Laid-Open No. 61-131807. [Problems to be Solved by the Invention] The above-mentioned prior technology is as described above. The load change when an electric drill is inserted into the surface of a workpiece is detected by a load sensor. However, the change of the load is determined by The size of the feed varies, and the no-load current of the same electric rig also has individual differences, which has the problem that the load change cannot be detected with good accuracy. An object of the present invention is to provide an automatic feed control device capable of removing the problems of the foregoing prior art and detecting the load change when an infeed provided in an electric drill is bitten on the surface of a workpiece without any difference. . Another object is to provide a method for detecting the load change after drilling and drilling the workpiece with good accuracy. [Means for solving the problem] Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs In order to achieve the above-mentioned purpose, the present invention is an automatic feeding control device for automatically feeding an electric drill to a workpiece, and the first feature is: Means of electric drill current 时 during load rotation, and electric drill current 时 during no-load rotation, the increased current 値 current below the electric drill 设 set on the surface of the workpiece when the drill bit installed in the electric drill is biased The method of adding the voltage and current to obtain the first threshold, and the current of the electric drill rig becomes the first threshold, and the Chinese national standard (CNS) A4 specification (210 X 297 mm) is applied to this paper scale -5- Α7 410ίδ2 ____ Β7 ___ 5 2. In the description of the invention (3), the means for judging that the drill has been bitten into the forced workpiece. If based on this feature, the first threshold value 上述 is obtained based on the electric drill current 时 during no-load rotation. When the electric drill current 値 becomes the first reading or more, it is determined that the drill bit has been bitten into the The surface of the workpiece is processed. Therefore, the electric drill 値 current when each body of the electric drill is rotating without load can be used as the basis for determining the first one. As a result, there is no individual difference between the electric drill and the drill. It bites into the surface of the workpiece >> Also, the second feature of the present invention is that a second threshold 値 which is larger than the normal drill current 时 during the no-load rotation of the electric drill is set, and when the drill is inserted into the workpiece When the electric drill current 値 behind the surface becomes below the second threshold 具有, there are means for judging that the drill is finished drilling the workpiece. According to this feature, the accuracy of judging the end of the drill can be improved. [Embodiments of the invention] The present invention will be described in detail with reference to the drawings. Fig. 2 is a perspective view showing the overall configuration of the drilling machine. Fig. 3 is a right side view. An electromagnetic base 2 equipped with an electromagnet MG is formed in the lower end of the drilling machine body 1 inside. A sliding plate 36 is provided on the upper side of the drilling machine body 1 so as to be movable up and down along the side, and an electric drill 3 is supported on the sliding plate 36. The drilling machine body 1 is provided with a feed motor 4 necessary for moving the slide plate 36 up and down, and a transmission shaft driven by the feed motor 4 is provided with a clutch. The three handles 39, 39, 39 are installed on the drilling machine body 1 through the clutch. When the three handles are turned when the clutch is removed, the electric drill 3 is manually operated. The paper size is applicable to the country of China. Standard (CNS) A4 specifications (210 * 297mm; 8Π (please read the precautions on the back before filling this page) i equipment ---- Γ order il ·! ---- line work consumption of the Intellectual Property Bureau of the Ministry of Economic Affairs Printed by the cooperative -6- 410182 a? ___B7_ V. Description of the invention (4) For the workpiece to be moved forward or backward. (Please read the note on the back before filling out this page.) Also, on the back side of the above sliding plate _ 3 6 A recessed portion (not shown) having an inclined surface is formed up and down. The recessed portion of the sliding plate 36 is moved as the electric drill 3 is lowered. When a drill provided in the electric drill 3 is fed to the drill, When it is sharp, it will act on the limit switch (not shown). The above-mentioned electric drill 3 is provided with a circular drill 5 which is rotated by a drive motor (not shown), and the drill 5 is located at the lower end of the electric drill 3 The mandrel 1 1 is installed at the tip downward. The mandrel 1 1 is moved from the lower end of the drill body 1 to the side. The protruding bracket 12 is supported to be movable up and down. "Also, a center pin 5a is slidably provided in the drill 5 above. A switch knob provided on the front of the above-mentioned drilling machine body 1 The 40 printed by the property bureau employee consumer cooperative is used to operate the start switch 6, which is a two-stage movement, and the three contacts 6A, 6B, 6C of the start switch 6 are turned on in a predetermined order. For example, In the circuit diagram of the first figure described later, the contacts 6A and 6C are closed first, and then the contacts 6C and 6B are closed. Therefore, when the switch button 40 is operated, the electromagnet MG inside the electromagnetic base 2 is first Excitation and the drilling machine body 1 is fixed to the workpiece, and then, the feed motor 4 and the drive motor are driven. When the button is engaged with the clutch provided on the transmission shaft, the electric drill 3 and the feed motor 4 are driven. Connect and perform automatic feed. The function of the driving part of the present invention is described below with reference to Figure 1. The first figure is a circuit diagram for explaining the function of the driving part. The drilling machine body 1 is placed on the workpiece. Predetermined position when the above-mentioned switch button 40 is operated First, the contact 6 A of the start switch 6 is closed. As a result, the electromagnet MG provided inside the above-mentioned electromagnetic base 2 is excited, and the drilling machine 1 applies the Chinese National Standard (CNS) A4 specification for this paper size ( 210 X 297 male «） A7 410182 _B7 V. Description of the invention (5) Fixed to the workpiece. Then, when the contacts 6 B and 6 C are closed, the drive motor 5 2 of the electric drill 3 is driven, and the drive is passed through the rectifier. 5 3 is connected to the feed motor 4. The electric path of the drive motor 5 2 is provided with a current detection transformer 5 4, and the load variation applied to the drive motor 5 2 is changed by the current detection transformer 54 into a current change. Detected. The detection current detected by the current detecting transformer 5 4 is rectified by the rectifier 5 5 and smoothed by a resistor 5 6 and a capacitor 5 7 and is inserted into the microcomputer 5 8 »Start driving as described above After the motor 52 and the feed motor 4, the three handles 39, 39, and 39 are rotated to lower the center pin 5a in the drill 5 of the electric drill 3 until it abuts on the end formed on the surface of the non-processed object. When the clutch is engaged at the punching marker position, the electric drill 3 is connected to the feed motor 4 for automatic feed. In addition, when the drill bit 5 of the electric drill 3 is bited on the surface of the workpiece and the load applied to the drive motor 5 2 is changed, the change becomes a change in the detection current detected by the current detection transformer 5 4 and input to the microcomputer 5 8. The microcomputer 58 is controlled by the no-load current detection method according to the present invention described later. When the change in the detection current is detected, the on-time of the photoelectric three-terminal bidirectional controllable sand switching element TR 1 (photo · triode AC switch) is controlled. That is, the phase is controlled, and the signal of the feed motor 4 is increased or decelerated. That is, the feed motor 4 is controlled to be faster than the initial speed at which the drill 5 bites into the surface of the workpiece, and is a deceleration that can be increased at a higher speed or decelerated at a lower speed. Results | The electric drill 3 is fed at a higher speed or a lower speed than the original speed, and the workpiece is drilled by the drill 5 The paper size is in accordance with the Chinese National Standard (CNS) A4 (210 * 297 mm) ) (Please read the precautions on the back of Jing before filling out this page) -------- I Order ------------ Printed by the Industrial and Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs-8- A7 410182 _B7__ 5. Description of the invention (6) Hole. The load change during the drilling operation is continuously monitored by the current detecting transformer 54, and is fed back to the feed motor 4. The rotation speed of the feed motor 4 is controlled to a speed suitable for the load. Press, in case, when an overload is detected, the circuit (not shown) will stop driving the motor 5 2 and the feed motor 4 in a state where the electromagnet MG of the electromagnetic base 2 is still excited, and not only prevent damage to each motor. It can also prevent the drilling inertia force of the drill from causing the drill body 1 to rotate the drill 5 as the center. Then • When the drill 5 passes through the bottom of the workpiece to finish drilling by the drill 5, the load of the drive motor 5 2 of the electric drill 3 becomes small. This load change is detected by the microcomputer 5 8 through the current detecting transformer 54, and the relay X 1 for drilling end detection is activated, and the contact XI 'is switched to reverse the feed motor 4 and control the photoelectricity. The tri-terminal triac is used to increase the turning speed of the feed motor 4. As a result, the electric drill 3 is retracted from the workpiece at a speed higher than the feed speed during the drilling operation. The detection of the load of the driving motor 5 2 when the drill 5 bites into the interface of the workpiece and the tip of the drill 5 passes under the workpiece is detected by the microcomputer 58 as described below. The steps are described below with reference to the flowchart in FIG. 4 and the time chart in FIG. 5. At time t1 in FIG. 5, when the above-mentioned contacts 66B and 6C are closed, the driving motor 52 starts to flow the drilling rig current i ′ and the electric drilling rig starts to rotate (step S1). When entering step S2, the microcomputer 58 sets the temporary threshold current a (in the order of several amps), and when proceeding to step S3, it starts from (please read the precautions on the back before filling in this page) ^ ------- I -^ > —- 1 11111 · The paper size printed by the Employees' Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs applies to Chinese standards < CNS) A4 size (210 X 297 male «> -9- 410182 A7 ._B7 V. Description of the invention (7) (Please read the French and Italian matters on the back before filling this page) The current detection transformer 54 detects the electric current i of the electric machine, that is, the current i flowing through the drive motor 52. Press this temporarily The electric current a is the imaginary plus the deviation of the electric drilling rig, the electric drilling rig supports the worst case of the machining accuracy of the metal parts, etc. The electric drilling rig electric current 时 when there is no load. The rotary drive by the feed motor 4 is set at The clutch of the drive shaft is ION. When the drill 5 of the electric drill 3 is lowered toward the surface of the workpiece, step S4 is judged. That is, it is judged whether the drill current i has become the above-mentioned temporary threshold current a. When the judgment of this step S 4 is affirmative, it proceeds to step S 5 and proceeds to It is judged whether the rig current i above the temporary threshold current a exceeds t seconds, for example, it lasts for 3 seconds. If this judgment is affirmative, the electric rig is no load because it has become larger than the temporary threshold current a In this case, it is determined that some abnormality has occurred, and the process proceeds to step S6 to issue an overload alarm. On the other hand, if the judgment of the above steps is negative, the process proceeds to step S7. And set the final threshold 値 b (= rig current i + bias 値 c). This bias 値 c is based on the variation of the power supply voltage, the diameter of the drill 5 and the material of the workpiece. The minimum increase of the rig current 値. Then, proceed to step S8 to determine whether the rig current i has reached the above final interval 値 b. If this judgment is negative, it will indicate that the drill 5 of the electric rig has not reached the processing The surface of the object. Press. If the judgment in step 8 above becomes affirmative (time t 2 in FIG. 5), proceed to step 9 to determine whether t seconds have elapsed, such as 3 seconds. If it becomes affirmative, then judge The drill bit 5 of the machine has been bitten into the surface of the workpiece. Then, go to step S10, and the microcomputer 58 will enter this paper. The size of the paper applies the Chinese National Standard (CNS) A4 (210 X 297 feet) -10- A7 410182 B7_ V. Description of the invention (8) < Please read the precautions on the back before filling this page) The phase control during the operation of the photoelectric triac TR1 (refer to Figure 1), so that The feed motor 4 is faster than the initial speed at which the drill 5 bites into the surface of the object to be processed, and can be turned into a high-speed rotation to increase or decelerate the rotation at a low speed. Then, in step S 1 1, it is replaced with the final threshold 値 t) = the temporary threshold 値 a. In step S 12, it is judged whether it is true. The difference between the drill current i and the final threshold 値 b. If this judgment is positive, it is still in the drilling operation. Therefore, a large load is applied to the drive motor 5 2. Thereafter, when the judgment in step S 12 becomes negative (t 3 in FIG. 5), it is known that the above-mentioned drill 5 has passed through the back of the workpiece, and proceeds to step SI 3 and the XI relay is energized. Press, if the cuttings in the hole are blocked by the cuttings escape ditch of the drill • Even if the drill 5 passes through the back of the workpiece, the drill current i is still shown as a chain line d in Figure 5 and will not become Too small, but because the final threshold 値 b is replaced with a temporary 'threshold 値 a' as in step S11 above, it can also be accurately detected in this case that the drill 5 has passed through the back of the work. The consumer cooperative is printed in step S 1 3. If the X 1 relay is energized, the contact XI 'connected to the feed motor 4 is switched, and the feed motor 4 is reversed. As a result, the electric drill will be pulled up. From the above description, it is clear that if the drilling machine current i of each drilling machine is unloaded based on the present invention, only the predetermined bias current 値 c * will be judged as the drilling tool 5 when the drilling machine current is increased. It has been bitten into the workpiece, so when the individual drilling machine has some deviations, it can also be used to detect the biting point of the drill with good accuracy. * This paper size applies to China National Standard (CNS) A4 specifications < 210 * 297芨 > • 11-5 # A7 _____B7_____ Printed by the Intellectual Property Bureau Staff Consumer Cooperatives of the Ministry of Economic Affairs 5. Description of the Invention (9) [Inventive Effect] If the invention according to item 1 of the scope of patent application according to the present invention is due to the drilling rig during unloaded rotation The current threshold is regarded as the basis of the first threshold, so 'the first threshold can be set according to each individual electric drill. Therefore, the biting time of the drill can be detected with good accuracy. If the invention according to item 2 of the patent scope of the present invention is applied, the overload of the electric drill can be detected to improve safety. If the invention according to item 3 of the patent application scope of the present invention is set as the second threshold, which is larger than the current of the normal rig when the electric drill is rotating without load, it is judged that the drill has been processed according to the second threshold. Therefore, even if the drill cuttings escape ditch blocks the cuttings and the drill current does not decrease to the normal drilling current when the electric drill is turning without load, it can detect that the drill has finished drilling the workpiece. If the invention according to item 4 of the scope of patent application of the present invention is used, when it is judged that the drill bit has been bitten on the surface of the workpiece, the speed will be increased or decreased, so the hole can be drilled at a speed suitable for the diameter of the drill, It can prevent the damage of drill or burnout of electric drill or feed motor. Brief Description of the Drawings Fig. 1 is a circuit diagram showing the constitution of one embodiment of the present invention. Fig. 2 is a perspective view of an example of a drilling machine to which the present invention is applied. Fig. 3 is a right side view of the drilling machine of Fig. 2. Fig. 4 is a flowchart showing essential functions of the present invention. This paper size is applicable to China National Standard (CNS) A4 specification (210 X 297 male t > ------ ------ installation ------ T order · '--- l · —Line I < Please read the precautions on the back before filling out this page) -12- A7 410182 _B7_ V. Description of the invention (10) Figure 5 is a time chart for explaining the main parts of the invention. [Explanation of symbols] 1 ... drilling machine body, 2 ... electromagnetic base, 3 ... electric drill, 4 ... feed motor, 5 ... drill, 6 ... start switch, 6 A, 6 B, 6 C ... contact , 5 2… driving motor, 5 4… current detection transformer, 5 8… microcomputer, X 1… relay, TR 1… photoelectric triac. ----! ^ -------- Order-/ ---- ^ --- 'line. (Please read the precautions on the back before filling out this page) Consumption of Shellfish, Intellectual Property Bureau, Ministry of Economic Affairs The paper size printed by the cooperative is applicable to China National Standard (CNS) A4 (210 X 297 mm) -13-