201107064 六、發明說明： 【發明所屬之技術領域】 本發明係關於旋轉切削工具。 【先前技術】 一般，印刷基板是從母板切出複數同一規格之小尺寸 印刷基板而製作。例如，將複數枚母板重疊施行孔加工後 ，對各種母板施行蝕刻和鍍敷處理以形成圖案，將施行該 等處理後的母板再度重疊複數枚，使用旋轉切削工具，個 別地切出同一規格之小尺寸印刷基板而製作。該切出加工 一般稱爲外形加工。此外，在進行孔加工和外形加工時， 爲了使預定的基板貫通以便能進行加工，一般係實施將基 板重疊在拋棄扳上，且重疊複數枚基板也是爲了提高生產 效率。 作爲進行這種外形加工的旋轉切削工具，以往有例如 如專利文獻1揭示的印刷基板加工用的路達銑刀（Router Bit )。 針對這種路達銑刀，通常是在工具本體的外周以預定 的扭轉角將切削屑排出溝設成螺旋狀，在該切削屑排出溝 的前刀面（rake face)和工具本體的外周面（或形成在工 具本體外周的外周退避面）之交叉稜線部，形成外周切割 刀。 然而，如第1圖之圖示’工具本體1的外周切割刀2 的扭轉角α，一般係從前端到基端被設成固定的角度。又 -5- 201107064 ，爲了使截斷切削屑的作用發揮，一般實施設置切削屑截 斷溝（以下，稱爲斷屑刀（Chip Breaker ))，其係凹設 在外周切割刀2’以用於截斷螺旋狀連續之外周切割刀2’ 。此外，第1圖中的符號B’係略示僅以預定數朝預定的 螺旋旋轉方向設置在工具本體外周的斷屑刀者，具體上是 指將被斷屑刀截斷的複數個外周切割刀的端點連結於該斷 屑刀的螺旋旋轉方向之假想線。該假想線B’的角度（切 斷角y?’）也是從前端到基端爲固定角度。此外，第1圖 係圖示切削屑排出溝或外周切割刀2’的螺旋旋轉方向爲 右（右扭轉），斷屑刀的螺旋旋轉方向爲左（左扭轉）。 [先行技術文獻] [專利文獻] [專利文獻1]日本特開2004-2〇259 1號公報 【發明內容】 [發明所欲解決之課題] 如前述，一般在進行母板的外形加工時，係複數枚重 疊加工。第2圖（a)係顯示利用具有極爲一般的右刀右 扭轉的外周切割刀之路達刀（Router )，進行外形加工時 的模式圖和切削阻抗者。於此情形下，切削阻抗R係表示 路達刀的送進方向和反方向的送進分力Fy、對送進 Fy作用於直角方向之背分力Fx及路達刀的軸方向之分力 亦即垂直分力Fz之合力，該切削阻抗R係對路達刀的送201107064 VI. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to a rotary cutting tool. [Prior Art] Generally, a printed circuit board is produced by cutting a plurality of small-sized printed boards of the same specification from a mother board. For example, after a plurality of mother boards are superimposed and subjected to hole processing, various mother boards are subjected to etching and plating treatment to form a pattern, and the mother sheets subjected to the above processes are overlapped in plurality, and individually cut out using a rotary cutting tool. Manufactured from a small-sized printed substrate of the same specification. This cutting process is generally referred to as profile processing. Further, in the hole processing and the outer shape processing, in order to allow a predetermined substrate to pass through so as to be able to be processed, it is generally practiced to superimpose the substrate on the disposable plate and to overlap the plurality of substrates in order to improve the production efficiency. As a rotary cutting tool for performing such external shape processing, for example, a router bit for processing a printed circuit board disclosed in Patent Document 1 has been known. For such a road milling cutter, the cutting dust discharge groove is generally spirally formed at a predetermined twist angle on the outer circumference of the tool body, and the rake face of the chip discharge groove and the outer peripheral surface of the tool body are generally provided. (or a peripheral ridge portion formed on the outer peripheral retracting surface of the outer periphery of the tool body) to form a peripheral cutting blade. However, as shown in Fig. 1, the torsion angle α of the outer peripheral cutter 2 of the tool body 1 is generally set to a fixed angle from the front end to the base end. Further, in addition to -5, 2011,070,64, in order to prevent the action of cutting chips, a chip cutting groove (hereinafter referred to as a chip breaker) is generally provided, which is recessed in the outer peripheral cutting blade 2' for cutting. Spiral continuous outer peripheral cutting knife 2'. Further, the symbol B' in Fig. 1 is a schematic view showing a chip breaker which is disposed on the outer circumference of the tool body only in a predetermined number of spiral rotation directions, and specifically refers to a plurality of peripheral cutters which are cut by the chip breaker. The end point is connected to the imaginary line of the spiral rotation direction of the chip breaker. The angle (cutting angle y?') of the imaginary line B' is also a fixed angle from the front end to the base end. Further, Fig. 1 shows that the spiral rotation direction of the chip discharge groove or the outer peripheral cutter 2' is right (right twist), and the spiral rotation direction of the chip breaker is left (left twist). [PRIOR ART DOCUMENT] [Patent Document 1] [Patent Document 1] Japanese Laid-Open Patent Publication No. 2004-2〇 259 No. 1 (Invention) [Problems to be Solved by the Invention] As described above, generally, when performing the outer shape processing of the mother board, Multiple overlapping processing. Fig. 2(a) shows a schematic diagram and cutting resistance when the shape is machined using a router that has a very peripheral right-to-right torsion outer peripheral cutter. In this case, the cutting resistance R represents the feeding force component Fy of the feeding direction and the reverse direction of the Luda knife, the back component force Fx acting on the feeding direction Fy in the right angle direction, and the component force of the axial direction of the road knife. That is, the combined force of the vertical component force Fz, the cutting resistance R is the delivery of the Luda knife
-6- 201107064 進方向朝左斜後方作動。如第2圖（b)所示之藉由該切 削阻抗R使外形加工中的路達刀彎曲之加工結果，加工側 面形成倒塌形狀，特別是在工具前端側經切削加工的部分 之倒塌量5 (相當於工具前端的撓曲）變大。 該倒塌量（5過大時，不僅無法滿足印刷基板被要求的 尺寸精確度，而且在外形加工結束時，將路達刀朝上方拉 出之際，由於加工側面形成倒塌形狀，因此外周切割刀（ 特別是工具前端側的外周切割刀）容易接觸到加工側面， 而有使外周切割刀受損、使工具耐久性劣化之問題。 又，由於將母板複數枚重疊進行外形加工，若是無法 順利地進行切削屑排出，在僅進行短距離之外形加工時， 亦有因爲切削屑堆積而折損工具的問題。 再者，本發明者等獲得關於以下問題之見解，即對於 實際上發揮切削作用的外周切割刀（切削屑排出溝）的扭 轉角，若是單純地使工具基端側大於工具前端側，則因爲 基端側的切削屑排出溝的扭轉角之影響而提高切削屑排出 性，但另一方面，因爲外周切割刀的扭轉角相異而使得切 削阻抗以扭轉角的變化點爲境界形成相異，這個原因使得 加工面的精確度劣化、外周切割刀受損或誘發工具本身的 折損。 本發明係本發明者等，針對旋轉切削工具的切削屑排 出溝（外周切割刀）的扭轉角進行硏究之結果，獲得藉由 使扭轉角從工具前端朝向基端側逐漸變大的方式，可謀求 進一步加工性及耐久性之提高的見解而完成者，提供一種 [ 201107064 實用性極爲優異之旋轉切削工具，其相較於扭轉角爲固定 之習知之旋轉切削工具，能長距離維持良好的切削加工》 [解決課題之手段] 參照附圖說明本發明之要旨。 關於一種旋轉切削工具，其係在工具本體1的外周形 成有複數個從工具前端朝向基端側之螺旋狀切削屑排出溝 3，在該切削屑排出溝3的前刀面和前述工具本體1的外 周面或形成在前述工具本體1的外周的外周退避面之交叉 稜線部’形成有外周切割刀2，其特徵爲：使前述外周切 割刀2的扭轉角〇：從工具前端朝向基端側漸增。 又，關於一種旋轉切削工具，其係如申請專利範圍第 1項記載的旋轉切削工具，其中，前述扭轉角《^係設定成 20〜35°。 又’關於一種旋轉切削工具，其係如申請專利範圍第 1項記載的旋轉切削工具，其中，將該扭轉角α設定成前 述扭轉角α在工具前端部和工具基端部之角度差爲丨〜丨〇。 〇 又，關於一種旋轉切削工具，其係如申請專利範圍第 2項記載的旋轉切削工具，其中，將該扭轉角£^設定成前 述扭轉角α在工具前端部和工具基端部之角度差爲ι~ι〇° 〇 又，關於一種旋轉切削工具，其係如申請專利範圍第 1至4項記載的旋轉切削工具，其中，凹設在前述外周切 -8 - 201107064 割刀2以用於截斷切削屑之斷屑刀4，係佾著預定的螺旋 旋轉方向並設複數支，該斷屑刀4係以前述螺旋旋轉方向 和前述外周切割刀2以預定的交叉角7交叉之方式被裝設 ，構成爲該交叉角7從工具前端朝向基端側爲不變或漸增 〇 又，關於一種旋轉切削工具，其係如申請專利範圍第 5項記載的旋轉切削工具，其中，將該交叉角r設定成前 述交叉角r在工具前端部和工具基端部之角度差爲 〇 又，關於一種旋轉切削工具，其係如申請專利範圍第 6項記載的旋轉切削工具，其中，前述工具本體1的直徑 係設定成該直徑從工具前端朝向基端側漸增之前方錐形狀 〇 又，關於一種旋轉切削工具，其係如申請專利範圍第 7項記載的旋轉切削工具，其中，前述直徑的錐角係設定 成 0_5~4°。 又，關於一種旋轉切削工具，其係如申請專利範圍第 6項記載的旋轉切削工具，係工具直徑爲〇· 5〜2mm之印刷 基板加工用之路達刀。 又，關於一種旋轉切削工具，其係如申請專利範圍第 8項記載的旋轉切削工具，係工具直徑爲〇.5〜2 mm之印刷 基板加工用之路達刀。-6- 201107064 The direction of the movement moves backwards to the left. As shown in Fig. 2(b), as a result of the cutting resistance R, the processing of the Luda knife in the outer shape processing results in a collapsed shape on the machined side, in particular, the amount of collapse of the portion on the tool leading end side. (equivalent to the deflection of the front end of the tool) becomes larger. The amount of collapse (5 is too large, not only can not meet the required dimensional accuracy of the printed substrate, and at the end of the shape processing, when the road knife is pulled upward, the peripheral cutting blade is formed due to the collapsed shape of the machined side ( In particular, the outer peripheral cutting blade on the tool front end side easily comes into contact with the machined side surface, and the outer peripheral cutting blade is damaged and the durability of the tool is deteriorated. Further, since the mother board is overlapped and the outer shape is processed, it is impossible to smoothly In the case of performing the cutting of the chips, the problem of the tool is lost due to the accumulation of the chips. The inventors of the present invention have obtained the knowledge that the periphery is actually capable of performing the cutting action. When the torsion angle of the cutter (chip discharge groove) is simply such that the tool base end side is larger than the tool tip end side, the chip discharge performance is improved by the influence of the torsion angle of the chip discharge groove on the base end side, but the other is On the other hand, because the torsion angles of the peripheral cutters are different, the cutting impedance is differentiated by the change point of the twist angle. For this reason, the accuracy of the machined surface is deteriorated, the peripheral cutting blade is damaged, or the tool itself is damaged. The present inventors have studied the twist angle of the chip discharge groove (outer peripheral cutting blade) of the rotary cutting tool. As a result, it is possible to obtain a rotating cutting tool with excellent practicality by providing a view that the torsion angle is gradually increased from the tip end of the tool toward the proximal end side, and further improvement in workability and durability can be achieved. Compared with a conventional rotary cutting tool in which the torsion angle is fixed, it can maintain a good cutting process over a long distance. [Means for Solving the Problem] The gist of the present invention will be described with reference to the drawings. A rotary cutting tool is attached to a tool. The outer circumference of the main body 1 is formed with a plurality of spiral chip discharge grooves 3 from the tool tip end toward the base end side, and the rake face of the chip discharge groove 3 and the outer peripheral surface of the tool body 1 or the tool body 1 are formed. The outer peripheral cutting blade 2 is formed by the intersecting ridge portion of the outer peripheral retreating surface, and is characterized in that the outer peripheral cutting blade is provided The torsion angle 2 of 2 is gradually increased from the tip end of the tool toward the base end side. The rotary cutting tool according to claim 1 is the rotary cutting tool according to the first aspect of the invention, wherein the twist angle is set to 20 A rotary cutting tool according to the first aspect of the invention, wherein the torsion angle α is set to the torsion angle α at the tool front end portion and the tool base end portion. The rotary cutting tool according to the second aspect of the invention is the rotary cutting tool according to the second aspect of the invention, wherein the twist angle is set to the twist angle α at the front end of the tool. The angle difference between the base end of the tool and the base of the tool is ι~ι〇°. Further, regarding a rotary cutting tool, the rotary cutting tool according to the first to fourth aspects of the patent application, wherein the recess is set in the outer circumference of the above-mentioned -8 - 201107064 The cutter 2 is used for cutting the chip breaking cutter 4, and is provided with a predetermined spiral rotation direction and is provided with a plurality of branches, the chip breaker 4 is in the aforementioned spiral rotation direction and the aforementioned outer circumference cutter 2 The predetermined intersection angle 7 is arranged in such a manner that the intersection angle 7 is constant or increasing from the tool front end toward the base end side. Regarding a rotary cutting tool, it is described in item 5 of the patent application scope. The rotary cutting tool, wherein the intersection angle r is set such that the angle of intersection r is an angle difference between the tool front end portion and the tool base end portion, and a rotary cutting tool is described in the sixth item of the patent application scope. The rotary cutting tool, wherein the diameter of the tool body 1 is set such that the diameter gradually increases from the front end of the tool toward the base end side, and the shape of the rotary cone is related to a rotary cutting tool as described in item 7 of the patent application. The rotary cutting tool in which the taper angle of the aforementioned diameter is set to 0_5 to 4°. Further, a rotary cutting tool according to the sixth aspect of the invention is a rotary cutting tool according to the sixth aspect of the invention, which is a Luda knife for processing a printed circuit board having a tool diameter of 〇·5 to 2 mm. Further, a rotary cutting tool according to the eighth aspect of the invention is a rotary cutting tool according to the eighth aspect of the invention, which is a Luda knife for printing a substrate having a tool diameter of 〇5 to 2 mm.
] [發明之功效] -9 - 201107064 本發明係以上述方式構成，因此相較於切削屑排出溝 的扭轉角爲固定之習知之旋轉切削工具，能長距離維持良 好的切削加工，係一實用性極爲優異之旋轉切削工具。 【實施方式】 根據圖式簡單地說明認爲適合本發明之實施形態並顯 示本發明之作用。 使工具本體1 一邊旋轉一邊接觸被加工物，將該被加 工物加工。此時，因爲外周切割刀2 (切削屑排出溝3 ) 的扭轉角α爲愈工具前端愈小而愈基端側愈大，因此能抑 制倒塌，從基板等拉出工具時可防止外周切割刀受損。又 ，於基端側不易產生切削屑堆積，加工性及耐折損性提高 〇 具體而言，起因於工具前端側的扭轉角α小，工具本 體1的倒塌被抑制，特別是工具前端部的倒塌量5顯著地 變小，當外形加工結束時，於將路達刀朝上方拉出之際， 外周切割刀和加工側面之接觸被抑制，而防止外周切割刀 受損。又，起因於工具基端側的扭轉角α大，切削屑排出 性提高而防止切削屑堆積，工具之耐折損性提高。再者， 因爲使扭轉角α從工具前端朝向基端側逐漸地增大，與單 純地使扭轉角α在工具前端側和工具基端側相異的情形不 同，解決了因爲外周切割刀2的扭轉角不同，使得原因是 切削阻抗以扭轉角的變化點爲境界而相異之加工面精確度 劣化、外周切割刀受損或誘發工具本身之折損的問題。 -10- 201107064 又，經外周切割刀2切削之切削屑被引導至切削屑排 出溝3而排出，但一部分切削屑係透過斷屑刀4朝工具的 旋轉方向後方移動。此時，如第3圖所示，如果外周切割 刀2和斷屑刀4的交叉角γ小，則前述切削屑之移動變得 困難，使得切削屑排出性惡化以至折損。因此，例如爲了 提高切削屑排出性以使工具耐折損性提高，可構成爲使外 周切割刀2和斷屑刀4(的螺旋旋轉方向）的交叉角r ， 從工具前端朝向基端側爲不變或漸增。於此情形下，構成 爲在工具基端側形成比工具前端側更大的交叉角7，而可 使前述切削屑排出性提高以使耐折損性提高。 再者，針對直徑小的路達刀，爲了保持路達刀之強度 而設計成前方錐形狀之情形下，仍可獲得與直型同等或者 同等以上之效果，因此亦可設計成前方錐形狀。 [實施例] 根據第3至8圖說明關於本發明之具體實施例。 本實施例係一旋轉切削工具，其係於由刀部和柄部所 構成的工具本體1之該刀部的外周，形成有複數個從工具 前端朝向基端側之螺旋狀的切削屑排出溝3，該切削屑排 出溝3的前刀面和前述工具本體的外周面或形成在前述工 具本體的外周的外周退避面之交叉稜線部，形成有外周切 割刀2;且其係構成爲前述外周切割刀2的扭轉角α從工 具前端朝向基端側漸增；且其係刀部的直徑 D爲 0.5〜2mm之印刷基板加工用的路達刀。此外，本實施例係 i S Ϊ -11 - 201107064 以鄰接的切削屑排出溝3在工具周方向交叉的方式，在其 交叉稜線部形成外周切割刀2，亦即在切削屑排出溝3-朝 向工具旋轉方向的面爲前刀面，朝向與工具旋轉方向相反 方向的部分（面）爲對外周切割刀2具有預定的外周退避 角之外周退避面。 此外，由於刀部的直徑D (工具直徑D)小於0.5mm 時，耐折損性非常低，因此在外周切割刀受損或倒塌量成 爲問題之前就發生刀折損，而無法確實地發揮後述'作用效 果。又，大於2mm時，則由於剛性提高，倒塌量變小而 無法確實地發揮後述作用效果。本實施例係採用直徑D 爲1 · 0mm者。 具體地說明各部分》 外周切割刀2 (切削屑排出溝3 )的扭轉角α係設定 成20〜35°。該扭轉角α小於20°時，切削屑之排出性惡化 。又，大於35°時，容易出現毛邊使得折損壽命變短。 再者，扭轉角α係設定成在工具前端部和工具基端部 的角度差爲1〜13°。具體而言，前述外周切割刀2的扭轉 角α被形成爲從工具前端朝向基端側逐漸地變大，工具前 端側預定位置的扭轉角α和工具基端側預定位置的扭轉角 α之角度差，被設定爲1〜13°。本實施例中，從工具前端 起在工具直徑D的2倍以下位置的扭轉角α和刀長位置 的扭轉角α之角度差，係設定爲1〜13°。更具體而言，例 如第6圖的實施例No.l (直徑：1mm，刀長：6.5mm)中 ，從工具前端起在1.5mm位置（工具直徑D的2倍以下 -12- 201107064 )的扭轉角〇：和從工具前端起在6.5mm位置（刀長位置 )的扭轉角α之角度差’係設定爲2·5°。此外，後述切斷 角/5的測定位置亦與扭轉角α的測定位置同樣。 當前述扭轉角在工具則端部和工具基端部之角度差爲 小於1。時，無法獲得加工性及耐折損性提高之效果。又’ 大於1 0 °時，切削阻抗的變化變大使得較易折損’因此較 佳爲10°以下。 又，扭轉角α係設定成在任一點皆成爲2 0~40°之範圍 。本實施例中，將工具前端部的扭轉角α設定成27·5°’ 將工具基端部的扭轉角α設定成3 0°，使扭轉角α在工具 前端部和工具基端部的角度差成爲約2.5°»此外，扭轉角 α係以20〜35°之範圍較佳。 又，本實施例中，在工具本體1(刀部）的外周，除 了切削屑排出溝3及外周切割刀2之外，沿著預定的螺旋 旋轉方向並設著複數用於截斷切削屑之斷屑刀4。該斷屑 刀4係設成與外周切割刀2交叉，第3圖中，以切斷角召 表示將藉由斷屑刀截斷的複數外周切割刀的端點結合在該 斷屑刀的螺旋旋轉方向之假想線Β和工具的中心軸所構成 之角。 其中，如第3圖所圖示，將上述切斷角/3和上述扭轉 角α之和，定義爲交叉角7 ，將180° -交叉角r ，定義爲 外周切割刀角0。 本實施例中，進行調整並構成爲使交叉角r朝向工具 基端側不變或漸增，使切斷角々從工具前端朝向基端側不 [s] -13- 201107064 變、漸減或漸增。此外，如第3圖所示，外周切割刀2的 扭轉角α係表示以工具中心軸爲基準而將與工具中心軸形 成的角的右方向作爲正方所測定者，另一方面，斷屑刀4 的切斷角；5係表示以工具中心軸爲基準而將與工具中心軸 形成的角的左方向作爲正方所測定者。本實施例中，構成 爲工具前端側的交叉角r和工具基端側的交叉角r之角度 差爲0~16°。例如第6圖的實施例No.l (直徑：lmm，刀 長：6.5mm)爲外周切割刀2的螺旋方向爲右（右扭轉： 扭轉角α爲未達9 0°)，且斷屑刀4的螺旋方向爲右（右 扭轉：切斷角yS爲超過9(Γ )。將工具前端部（距離工具 前端1.5mm之位置）的扭轉角α設定爲27.5°，將切斷角 設定爲1〇〇°，因此工具前端部的交叉角7爲127.5°，外 周切割刀角0爲52.5°。另一方面，將工具基端部（刀長 位置：距離工具前端6.5mm之位置）的扭轉角α設定爲 3〇°，將切斷角召設定爲9 9°，因此工具基端部的交叉角r 爲129°，外周切割刀角0爲5Γ。因此從工具前端朝向工 具基端側，將扭轉角α的角度差設定成大2.5° ( 3 0° — 27.5°)，將切斷角万設定成小厂（100°— 99°)，將交叉 角的角度差設定成大1.5° ( 129°- 127.5°)。 工具前端側的交叉角r和工具基端側的交叉角T之角 度差大於15°時，工具基端側的外周切割刀的外周切割刀 角0太小，容易產生受損，直徑穩定性低（在受損處測定 直徑時被測定爲較小），或容易產生毛邊或折損，因此 15°以下較佳。 -14- 201107064 工具本體（刀部）的直徑係如第3圖所圖示，亦可設 定爲固定（直型），爲了進一步抑制工具本體1的倒塌， 如第4圖所圖示，亦可設定成從工具前端朝向基端方向漸 增之所謂的前方錐形狀。本實施例中，設定成前方錐形狀 。該直徑的錐角係設定成〇·5〜5°。若錐角小於0.5°，則工 具本體1之倒塌抑制效果將與直型大致相同，無法顯著地 顯現其差。又，若大於4°，則工具基端側之剛性變高，此 外工具前端側和工具基端側之切削阻抗差變的太大，在工 具軸方向均等加工變的困難，而難以獲得所要的加工尺寸 精確度和加工面粗度，因此4°以下較佳。本實施例中，設 定成1.12° 。 因而，如第5圖（a)所圖示之習知例（扭轉角〇：’固 定、直型）中，例如將積層之基板X’加工時，產生了顯 著的倒塌（工具前端的倒塌量5)，但以使外周切割刀2 的扭轉角α小到工具前端程度大到基端側程度的方式，能 抑制在工具前端部的倒塌量5 (第5圖（b))，進一步 在如上述之本實施例（第5圖（c ))中，以工具基端側 的剛性高且前端側的阻抗小之方式，將積層之基板X加 工時更能抑制該當倒塌，從基板拉出時能防止外周切割刀 2的前端受損。此外，圖中符號3’爲切削屑排出溝，4’爲 斷屑刀。如本實施例，於設計成前方錐形狀的情形下，如 第5圖（a )，由於加工側面位於工具前端的左側側面上 方（Z部分）之可能性低，因此該當加工側面和外周切割 刀2接觸困難，而可抑制外周切割刀2受損，因此可獲if -15- 201107064 與直型同等或者同等以上之效果（參照後述實驗例、第8 圖）。 本實施例係如上述般構成，因此當一邊使工具本體1 旋轉，一邊使其接觸被加工物以將該被加工物加工時，由 於外周切割刀2 (切削屑排出溝3)的扭轉角α小到工具 前端程度大到基端側程度，因此能抑制倒塌（特別是工具 前端部的倒塌量5顯著地小），從基板等拉出工具時能防 止外周切割刀受損。又，在基端側不易產生切削屑堆積， 提高加工性及耐折損性。 因此，相較於切削屑排出溝的扭轉角爲固定之習知之 旋轉切削工具，本實施例係可長距離維持良好的切削加工 之實用性極爲優異者。 以下說明有關根據本實施例之效果的實驗例。 以第7圖上部所示之實驗條件比較實施例（第6圖中 之例Ο和習知例（第6圖中之例14)的折損壽命的結果 顯示於第7圖之圖表（實驗例1)，該實施例（第6圖中 之例1) 係直徑l.Ommx刀長6.5mm、錐角1.12°的路達 刀，具有如第6圖所示之參數，該習知例（第6圖中之例 14)係使扭轉角及切斷角不改變，扭轉角爲第6圖的基端 側扭轉角且固定，切斷角爲第6圖的基端側切斷角且固定 ，工具本體的直徑爲直型以外，具有與實施例同樣的參數 。此外，前方錐形狀之路達刀的直徑，於本實施例係顯示 基端側的直徑。 又，針對各路達刀，以數位顯微鏡觀察1 m切削後之 -16 - 201107064 外周切割刀受損、摩耗狀態，將結果顯示於第8圖（實驗 例2)。此外，第8圖中〇所包圍的部分爲外周切割刀受 損的部分。 根據第7、8圖，可確認實施例不僅不易產生外周切 割刀受損，相較於習知例亦提高折損壽命，因此確認本實 施例相較於習知之旋轉切削工具，可長距離維持良好的切 削加工。 【圖式簡單說明】 第1圖係習知例之主要部分之槪略說明側視圖。 第2圖係有關切削阻抗和倒塌之說明圖。 第3圖係本實施例之主要部分之槪略說明側視圖。 第4圖係本實施例之主要部分之槪略說明側視圖。 第5圖係比較本實施例和習知例之加工時的狀態之槪 略說明圖。 第6圖係顯示本實施例及習知例之各參數之表。 第7圖係顯示實驗例1的實驗條件及實驗結果之說明 圖。 第8圖係顯示實驗例2的實驗結果之照片。 【主要元件符號說明】 1 :工具本體 2 =外周切割刀 3 :切削屑排出溝 ^ -17- 201107064 4 :斷屑刀（Chip Break) α :扭轉角 r :交叉角 -18 -[Effects of the Invention] -9 - 201107064 The present invention is constructed in the above-described manner, so that the rotary cutting tool having a fixed torsion angle of the cutting waste discharge groove can maintain a good cutting process over a long distance, and is practical. Extremely excellent rotary cutting tool. [Embodiment] The embodiments of the present invention are considered to be suitable for the present invention and the effects of the present invention are shown. The tool body 1 is brought into contact with the workpiece while rotating, and the workpiece is processed. At this time, since the torsion angle α of the outer peripheral cutting blade 2 (the chip discharge groove 3) is smaller as the tip end of the tool becomes larger, the larger the base end side is, the collapse can be suppressed, and the outer peripheral cutting blade can be prevented when the tool is pulled out from the substrate or the like. Damaged. Further, it is less likely to cause chipping on the base end side, and the workability and the fracture resistance are improved. Specifically, the torsion angle α due to the tip end side of the tool is small, and the collapse of the tool body 1 is suppressed, particularly the collapse of the tip end portion of the tool. The amount 5 is remarkably small, and when the outer shape processing is finished, the contact between the outer peripheral cutting blade and the machined side is suppressed while the outer peripheral cutting blade is prevented from being damaged when the road knife is pulled upward. Further, the torsion angle α due to the proximal end side of the tool is large, the chip discharge property is improved, and the accumulation of chips is prevented, and the fracture resistance of the tool is improved. Further, since the torsion angle α is gradually increased from the tip end of the tool toward the proximal end side, unlike the case where the torsion angle α is simply different between the tool leading end side and the tool base end side, the outer peripheral cutting blade 2 is solved. The difference in the torsion angle is caused by the fact that the cutting impedance is deteriorated by the change point of the torsion angle, the accuracy of the machined surface is deteriorated, the peripheral cutting blade is damaged, or the damage of the tool itself is induced. -10- 201107064 Further, the chips cut by the outer peripheral cutting blade 2 are guided to the chip discharge groove 3 and discharged, but a part of the chips are moved rearward in the rotation direction of the tool through the chip breaker 4. At this time, as shown in Fig. 3, if the crossing angle γ of the outer peripheral cutter 2 and the chip breaker 4 is small, the movement of the chips is difficult, and the chip discharge property is deteriorated or broken. Therefore, for example, in order to improve the chip discharge property and improve the fracture resistance of the tool, the intersection angle r of the outer peripheral cutter 2 and the chip breaker 4 (the direction of the spiral rotation) can be configured so as not to be from the tool tip toward the base end side. Change or increase. In this case, it is configured to form a larger crossing angle 7 than the tool leading end side on the tool base end side, and the above-described chip discharge performance can be improved to improve the fracture resistance. Further, in the case where the Luda knife having a small diameter is designed to have a front tapered shape in order to maintain the strength of the Luda knife, an effect equivalent to or equal to that of the straight type can be obtained, and therefore, the front tapered shape can be designed. [Embodiment] A specific embodiment of the present invention will be described based on Figs. 3 to 8. The present embodiment is a rotary cutting tool which is formed on the outer circumference of the blade portion of the tool body 1 which is formed by the blade portion and the shank portion, and is formed with a plurality of spiral chip discharge grooves from the tool tip end toward the base end side. 3, the rake face of the chip discharge groove 3 and the outer peripheral surface of the tool body or the intersection ridge line formed on the outer peripheral retracting surface of the outer periphery of the tool body, the peripheral cutting blade 2 is formed; and the outer circumference is configured The torsion angle α of the cutter 2 is gradually increased from the tip end of the tool toward the proximal end side, and the diameter D of the blade portion is 0.5 to 2 mm. Further, in the present embodiment, i S Ϊ -11 - 201107064, the outer peripheral cutting blade 2 is formed at the intersecting ridge line portion so that the adjacent chip discharge grooves 3 intersect in the tool circumferential direction, that is, in the chip discharge groove 3-direction The surface in the tool rotation direction is a rake face, and a portion (face) facing the direction opposite to the tool rotation direction is a peripheral retraction surface having a predetermined outer circumference retraction angle of the outer peripheral cutter 2 . In addition, since the diameter D (tool diameter D) of the blade portion is less than 0.5 mm, the fracture resistance is extremely low, so that the blade breakage occurs before the outer peripheral cutter is damaged or the amount of collapse becomes a problem, and the effect described later cannot be reliably performed. effect. Further, when the thickness is more than 2 mm, the amount of collapse is reduced due to an increase in rigidity, and the effect of the later described effects cannot be reliably exhibited. In this embodiment, the diameter D is 1 · 0 mm. Specifically, the torsion angle α of the outer peripheral cutting blade 2 (the chip discharge groove 3) is set to 20 to 35°. When the torsion angle α is less than 20°, the discharge property of the chips is deteriorated. Moreover, when it is more than 35 degrees, burrs are likely to occur, and the breaking life is shortened. Further, the torsion angle α is set such that the angular difference between the tip end portion of the tool and the end portion of the tool base is 1 to 13°. Specifically, the torsion angle α of the outer peripheral cutter 2 is formed to gradually increase from the front end of the tool toward the base end side, and the angle of twist α of the predetermined position on the front end side of the tool and the angle of the twist angle α of the predetermined position on the base end side of the tool are formed. The difference is set to 1 to 13°. In the present embodiment, the angular difference between the torsion angle α at the position twice or less of the tool diameter D and the torsion angle α at the blade length from the tip end of the tool is set to 1 to 13°. More specifically, for example, in the embodiment No. 1 (diameter: 1 mm, knife length: 6.5 mm) of Fig. 6, the position is 1.5 mm from the tip end of the tool (less than twice the diameter D of the tool -12 - 201107064) Torsion angle 〇: The angular difference θ between the torsion angle α at the 6.5 mm position (the tool length position) from the tip end of the tool is set to 2·5°. Further, the measurement position of the cutting angle /5 described later is also the same as the measurement position of the torsion angle α. When the aforementioned twist angle is at an angle difference between the end of the tool and the end of the tool base, it is less than one. When the workability and the fracture resistance are not improved, the effect is not obtained. Further, when it is larger than 10 °, the change in the cutting resistance becomes large, making it easier to break, so it is preferably 10 or less. Further, the torsion angle α is set to be in the range of 20 to 40° at any point. In the present embodiment, the torsion angle α of the tip end portion of the tool is set to 27·5°'. The torsion angle α of the tool base end portion is set to 30°, and the torsion angle α is at the angle of the tool front end portion and the tool base end portion. The difference becomes about 2.5°. In addition, the twist angle α is preferably in the range of 20 to 35°. Further, in the present embodiment, on the outer circumference of the tool body 1 (knife portion), in addition to the chip discharge groove 3 and the outer peripheral cutter 2, a plurality of cuts for cutting chips are provided along a predetermined spiral rotation direction. Chip cutter 4. The chip breaker 4 is disposed to intersect the outer cutter 2, and in FIG. 3, the end point of the plurality of peripheral cutters that are cut by the chip breaker is coupled to the spiral rotation of the chip breaker. The imaginary line of the direction and the angle formed by the central axis of the tool. Here, as shown in Fig. 3, the sum of the above-described cutting angle / 3 and the above-mentioned torsion angle α is defined as the intersection angle 7, and the 180° - intersection angle r is defined as the outer peripheral cutting blade angle 0. In this embodiment, the adjustment is performed and the cross angle r is made constant or increasing toward the base end side of the tool, so that the cut angle 变 does not change from the tool front end toward the base end side [s] -13- 201107064, gradually decreases or increases. . Further, as shown in Fig. 3, the torsion angle α of the outer peripheral cutter 2 indicates that the right direction of the angle formed with the tool center axis is measured squarely with respect to the tool center axis, and the chip breaker is also used. The cut angle of 4; the 5 series indicates the measurement of the left direction of the angle formed by the center axis of the tool with respect to the tool center axis as the square. In the present embodiment, the angle difference between the intersection angle r of the tool leading end side and the intersection angle r of the tool base end side is 0 to 16°. For example, the embodiment No. 1 (diameter: lmm, knife length: 6.5 mm) of Fig. 6 is that the spiral direction of the outer peripheral cutting blade 2 is right (right twist: the twist angle α is less than 90°), and the chip breaker The spiral direction of 4 is right (right twist: the cut angle yS is more than 9 (Γ). The twist angle α of the tool tip end (1.5 mm from the tool tip) is set to 27.5°, and the cut angle is set to 1 〇〇°, so the cross angle 7 of the front end of the tool is 127.5°, and the outer peripheral cutting angle 0 is 52.5°. On the other hand, the torsion angle of the tool base end (knife length position: 6.5 mm from the tool tip) α is set to 3〇°, and the cut angle is set to 9 9°, so the intersection angle r of the tool base end is 129°, and the outer circumference cutter angle 0 is 5Γ. Therefore, from the tool front end toward the tool base end side, The angle difference of the torsion angle α is set to be 2.5° (30° to 27.5°), the cut angle is set to small (100° to 99°), and the angle difference of the intersection angle is set to 1.5° (129). °- 127.5°). When the angle difference between the intersection angle r of the tool leading end side and the intersection angle T of the tool base end side is greater than 15°, the outer peripheral cutting of the tool base end side The peripheral cutting blade angle 0 is too small, is liable to be damaged, has low diameter stability (measured to be small when the diameter is measured at the damaged portion), or is liable to cause burrs or breakage, so that it is preferably 15 or less. -14- 201107064 The diameter of the tool body (knife part) can be set as fixed (straight type) as shown in Fig. 3. To further suppress the collapse of the tool body 1, as shown in Fig. 4, it can also be set to The front end of the tool is gradually increased in the direction of the base end. In the present embodiment, the front taper shape is set. The taper angle of the diameter is set to 〇·5 to 5°. If the taper angle is less than 0.5°, the tool The collapse suppressing effect of the body 1 will be substantially the same as that of the straight type, and the difference cannot be remarkably exhibited. Further, if it is larger than 4°, the rigidity of the tool base end side becomes high, and the cutting resistance difference between the tool leading end side and the tool base end side is further poor. It becomes too large to be equally difficult to machine in the direction of the tool axis, and it is difficult to obtain the desired processing dimensional accuracy and the processing surface roughness, so that it is preferably 4 or less. In this embodiment, it is set to 1.12°. Figure 5 (a) is illustrated In the conventional example (twist angle 〇: 'fixed, straight type), for example, when the laminated substrate X' is processed, a significant collapse (the amount of collapse of the tool tip 5) is generated, but the twist of the outer peripheral cutter 2 is made. The angle α is as small as the tip end of the tool to the base end side, and the amount of collapse 5 at the tip end portion of the tool can be suppressed (Fig. 5(b)), and further in the present embodiment as described above (Fig. 5(c) In the case where the rigidity of the base end side of the tool is high and the impedance of the front end side is small, it is possible to suppress the collapse of the laminated substrate X during processing, and it is possible to prevent the front end of the outer peripheral cutting blade 2 from being damaged when the substrate is pulled out from the substrate. In the figure, the symbol 3' is the chip discharge groove, and the 4' is the chip breaker. As in the present embodiment, in the case of designing the front tapered shape, as in Fig. 5(a), since the machining side is less likely to be located above the left side surface (Z portion) of the front end of the tool, the side and outer peripheral cutting blades should be processed. (2) It is difficult to contact, and the peripheral cutting blade 2 can be suppressed from being damaged. Therefore, if -15-201107064 is equivalent to or equal to the straight type (see the experimental example and the eighth drawing described later). Since the present embodiment is configured as described above, when the tool body 1 is rotated and the workpiece is brought into contact with the workpiece to process the workpiece, the torsion angle α of the outer peripheral cutter 2 (chip discharge groove 3) is obtained. It is as small as the front end of the tool to the base end side, so that the collapse can be suppressed (especially, the amount of collapse 5 of the tip end portion of the tool is remarkably small), and the peripheral cutting blade can be prevented from being damaged when the tool is pulled out from the substrate or the like. Further, it is less likely to cause chipping on the base end side, and the workability and the fracture resistance are improved. Therefore, this embodiment is excellent in the practicality of maintaining a good cutting process over a long distance compared to a conventional rotary cutting tool in which the torsion angle of the chip discharge groove is fixed. Experimental examples regarding the effects according to the present embodiment will be described below. The results of the fracture life of the comparative example (the example in Fig. 6 and the example (the example 14 in Fig. 6) of the comparative example shown in the upper part of Fig. 7 are shown in the graph of Fig. 7 (Experimental Example 1) This embodiment (Example 1 in Fig. 6) is a Luda knife having a diameter of 1.0 mm and a blade length of 6.5 mm and a taper angle of 1.12°, and has a parameter as shown in Fig. 6, which is a conventional example (6th) In the example 14), the torsion angle and the cutting angle are not changed, and the torsion angle is the base end side torsion angle of Fig. 6 and is fixed, and the cutting angle is the base end side cutting angle of Fig. 6 and is fixed. The diameter of the main body is the same as that of the embodiment, and the diameter of the road blade of the front taper shape is the diameter of the base end side in the present embodiment. Microscope observation 1 - 201107064 after cutting 1 m after cutting, damage and wear state of the outer cutter, the results are shown in Fig. 8 (Experimental Example 2). In addition, the part enclosed by the crucible in Fig. 8 is damaged by the peripheral cutter. According to Figures 7 and 8, it can be confirmed that the embodiment is not only difficult to cause damage to the peripheral cutting blade, but also compared with the conventional example. Since the high-break life is high, it is confirmed that the present embodiment can maintain a good cutting process over a long distance compared to the conventional rotary cutting tool. [Simplified Schematic Description] Fig. 1 is a schematic side view showing a main part of a conventional example. Fig. 2 is an explanatory view showing the cutting impedance and collapse. Fig. 3 is a schematic side view showing the main part of the embodiment. Fig. 4 is a schematic side view showing the main part of the embodiment. A schematic diagram for comparing the state of the processing of the present embodiment and the conventional example is shown. Fig. 6 is a table showing the parameters of the present embodiment and the conventional example. Fig. 7 shows the experimental conditions of the experimental example 1 and Fig. 8 is a photograph showing the experimental results of Experimental Example 2. [Explanation of main component symbols] 1 : Tool body 2 = peripheral cutting blade 3: chip discharge groove ^ -17- 201107064 4 : chip breaking Chip Break α : Torsion angle r : Cross angle -18 -