【正文】 supplied to the control unit and the machine tool by cards，punched tapes，or by magnetic tape．Eight—channel punched paper tape is the most monly used form of data input for conventional N／C systems．The coded instructions on the tape consist of sections of punched holes called blocks．Each block represents a machine function，a machining operation，or a bination of the two．The entire N／C program on a tape is made up of an accumulation of these successive data blocks．Programs resulting in long tapes all wound on reels like motionpicture film．Programs on relatively short tapes may be continuously repeated by joining the two ends of the tape to form a loop．Once installed，the tape is used again and again without further handling．In this case，the operator simply loads and unloads the parts．Punched tapes ale prepared on type writers with special tape—punching attachments or in tape punching units connected directly to aputer system．Tape production is rarely errorfree．Errors may be initially caused by the part programmer，in card punching or pilation，or as a result of physical damage to the tape during handling，etc．Several trial runs are often necessary to remove all errors and produce an acceptable working tape． While the data on the tape is fed automatically，the actual programming steps ale done manually．Before the coded tape may be prepared，the programmer，often working with a planner or a process engineer, must select the appropriate N／C machine tool，determine the kind of material to be machined，calculate the speeds and feeds，and decide upon the type of tooling needed. The dimensions on the part print are closely examined to determine a suitable zero reference point from which to start the program．A program manuscript is then written which gives coded numerical instructions describing the sequence of operations that the machine tool is required to follow to cut the part to the drawing specifications． The control unit receives and stores all coded data until a plete block of information has been accumulated．It then interprets the coded instruction and directs the machine tool through the required motions． The function of the control unit may be better understood by paring it to the action of a dial telephone，where，as each digit is dialed，it is stored．When the entire number has been dialed，the equipment bees activated and the call is pleted． Silicon photo diodes，located in the tape reader head on the control unit，detect light as it passes through the holes in the moving tape．The light beams are converted to electrical energy，which is amplified to further strengthen the signal．The signals are then sent to registers in the control unit, where actuation signals are relayed to the machine tool drives．?dāng)?shù)控技術(shù)數(shù)控技術(shù)數(shù)控技術(shù)數(shù)控技術(shù) 數(shù)控是可編程自動化技術(shù)的一種形式，通過數(shù)字、字母和其他符號來控制加工設(shè)備。（八）確定切削用量規(guī)劃進(jìn)給路線并進(jìn)行零件加工。（六）刀具選擇加工該零件選用直徑Φ20面銑刀加工毛坯表面、兩角的臺階；直徑為Φ12的立銑刀來加工凹槽、內(nèi)型腔；直徑為Φ6的球頭銑刀倒角；再選用Φ6中心鉆和直徑為14的鉆頭加工孔；Φ12的鏜刀鏜孔。（四）加工順序的安排根據(jù)上述工序的劃分方法，該案例零件先加工外形然后加工內(nèi)型腔、鉆孔等。該課題零件尺寸不大加工也不是很難，因為需要換約4把刀來加工，而機(jī)床自動換刀可提高加工效率，再加上學(xué)校的實習(xí)資源有限，所以選用法那科加工中心。數(shù)控臥式鏜、銑床和臥式加工中心適于加工各種復(fù)雜的箱體零件、泵體、閥體、殼體等。（二）機(jī)床選擇不同類型的零件應(yīng)在不同的數(shù)控機(jī)床上加工，要根據(jù)零件的設(shè)計要求選擇機(jī)床，數(shù)控車床適于加工形狀比較復(fù)雜的軸類零件和由復(fù)雜曲線回轉(zhuǎn)形成的模具內(nèi)型腔。一般的銑床都可以完成，因為要用多把刀才可完成為了提高加工效率所以選用加工中心。此外世界上各工業(yè)發(fā)達(dá)國家還將數(shù)控技術(shù)及數(shù)控裝備列為國家戰(zhàn)略物資，不僅采取重大措施來發(fā)展自己的數(shù)控技術(shù)及其產(chǎn)業(yè)，而且在“高精尖”數(shù)控關(guān)鍵技術(shù)和裝備方面對我國實行封鎖和限制政策。當(dāng)今世界各國制造業(yè)廣泛采用數(shù)控技術(shù)，以提高制造能力和水平，提高對動態(tài)多變市場的適應(yīng)能力和競爭能力。數(shù)控機(jī)床在各個機(jī)械制造業(yè)已成為大、中型企業(yè)的主要技術(shù)裝備。數(shù)控機(jī)床綜合了微電子、計算機(jī)、信息處理、自動檢測、自動控制、電機(jī)與拖動，電子和電力、精密測量、氣液壓及現(xiàn)代機(jī)械制造技術(shù)等多種先進(jìn)技術(shù)的機(jī)電一體化產(chǎn)品，是數(shù)控機(jī)床的心臟。本課題針對零件總體的工藝設(shè)計、主要工序的數(shù)控加工工藝設(shè)計及實際的加工訓(xùn)練，全面了解了殼體類零件的加工要求和總體生產(chǎn)過程、質(zhì)量的控制及保證措施。開題報告課題名稱： 零件的數(shù)控銑加工工藝設(shè)計及編程加工院系名稱： 甘肅機(jī)電職業(yè)技術(shù)學(xué)院 專 業(yè)： 數(shù)控技術(shù)班 級： G102201班 學(xué)生姓名： 一．課題研究的意義課題研究的零件設(shè)計到了銑削面、銑削輪廓、挖槽、鉆孔等需要多道工序才能完成，全面復(fù)習(xí)和鞏固數(shù)控銑削加工基本知識，并運用所學(xué)知識解決實際設(shè)計問題、提高分析問題、解決問題的能力。掌握各種手冊、文獻(xiàn)資料在設(shè)計中的運用方法。二．發(fā)展情況近幾年來，機(jī)械加工業(yè)大量采用數(shù)控機(jī)床取代傳統(tǒng)的普通機(jī)床進(jìn)行機(jī)械加工，普通機(jī)械逐漸被數(shù)控機(jī)械所代替。具有高精度，高效率，柔性自動化等特點決定了今后發(fā)展數(shù)控機(jī)床是我國機(jī)械制造業(yè)技術(shù)改造的必由之路，是工廠自動化的基礎(chǔ)。數(shù)控技術(shù)是用數(shù)字信息對機(jī)械運動和工作過程進(jìn)行控制的技術(shù)；是制造業(yè)實現(xiàn)自動的化、柔性化、集成化生產(chǎn)的基礎(chǔ)；是提高產(chǎn)品質(zhì)量、提高勞動生產(chǎn)率必不可少的物質(zhì)手段；是國防現(xiàn)代化的重要戰(zhàn)略物質(zhì)；是關(guān)系到國家戰(zhàn)略地位和體現(xiàn)國家綜合國力水平的重要基礎(chǔ)性產(chǎn)業(yè)。大力發(fā)展以數(shù)控技術(shù)為核心的先進(jìn)制造技術(shù)已成為世界各發(fā)達(dá)國家加速經(jīng)濟(jì)發(fā)展、提高綜合國力和國家地位的重要途徑。三．?dāng)?shù)控加工工藝設(shè)計過程