【正文】 a threeaxis machines would have an additional vertical movement of the spindle, for example ,four,five or sixaxis machines provide additional liner or rotary movements. There classes of NC systems are monly recognized. One of these is called pointtopoint or positioning NC where a cutting tool and workplace are positioned with respect to each other before a cut is taken, as exemplified by an NC drill press. The path between points is of little concern and is not particularly controlled. Another class, known as a straightcut NC system, involves movements, between points like pointtopoint NC but along straight or curved paths determined by the machine ways or slides. An NC turret lathe may be of the second class. A third class is continuouspath NC, or more formally continuous tool path control, which does contouring or profiling or lines, curves, or surfaces, of all shapes. One way of achieving continuous path NC is to move the work piece or cutter from point to point along a straight line or curve with many points spaced closely enough together so that the position path of the cut approximates a desired curve within limits required. Another way is to drive machine members say as saddle and the table on it, along coordinate axes at varying velocities controlled so that the resultant motion is along a particular line or curve.An NC machine may be controlled through an openloop circuit. The openloop system is the simplest and cheapest but does not assure accuracy. A signal that is an order for a certain action is issued by the control unit. This travel through the travels through the drive mechanism which imposes the action upon the controlled member of the machine. The basic drive mechanism for a table or other machine member in an openloop system is a stepping motor, also called a digital or pulse motor. It has, for example,49poles around the armature inside of 50 poles around he stator. Two poles are always aligned. Poles are energized to align the next two poles and turn the armature through a definite small angle each time a pulse of electricity is received. The motor turns the lead screw, which moves the table a corresponding distance, If, for example, a pulse stands for a movement, and a movement of mm is desired, he control unit issues 50 pulses。3~，6~。）號(hào)。最后感謝所有關(guān)心、幫助過我的朋友和同學(xué)！做好一個(gè)畢業(yè)設(shè)計(jì)真的不容易，衷心感謝我身邊所有的老師和同學(xué)！愿你們身體健康、工作順利！ 王超凡 2014年5月26日30參考文獻(xiàn)[1] 趙華. 模具設(shè)計(jì)與制作[M]. 北京: 清華大學(xué)出版社, 2009.[2] 黃平、朱文堅(jiān). 機(jī)械設(shè)計(jì)教程理論、方法與標(biāo)準(zhǔn)[M]. 北京: 清華大學(xué)出版社, 2010.[3] 郭鐵良. 模具制造工藝學(xué)[M]. 北京:高等教育出版社, 2008.[4] 趙昌盛. 實(shí)用模具材料應(yīng)用手冊(cè)[M]. 北京：機(jī)械工業(yè)出版社, 2005.[5] 王煥庭、李茂華、徐善國(guó). 機(jī)械工程材料[M]. 大連,大連理工大學(xué)出版社， 2000.[6] 屈華昌. 塑料成型工藝及模具設(shè)計(jì)[M]. 北京,高度教育出版社，2007.[7] 黃毅宏、李明輝. 模具制造工藝[M]. 北京: 機(jī)械工業(yè)出版社, 2003.[8] [M].西安:西北工業(yè)大學(xué)出版社,2000.[9] 宋濤、[M].北京:化學(xué)工業(yè)出版社,2003.[10]：中國(guó)輕工業(yè).[11] [M].廣州:華南理工大學(xué)出版社,1996.[12] [M].機(jī)械工業(yè)出版社,2005.[13] 蔣繼宏、王效岳 注塑模具典型結(jié)構(gòu)100例[M].北京：中國(guó)輕工業(yè)出版社，2000.[14] 王鵬駒、張杰 塑料模具設(shè)計(jì)師手冊(cè) 北京：機(jī)械工業(yè)出版社，2008.[15] :上?？茖W(xué)技術(shù)出版社,1985第一版[16] : 機(jī)械工業(yè)出版社,2002.[17] :中國(guó)石化出版社,2000.[18] : 機(jī)械工業(yè)出版社,2002.[19] : 機(jī)械工業(yè)出版社,2000.4附　錄 附錄一 塑料制件尺寸公差 （單位：mm）公稱尺寸精度等級(jí)12345678公稱數(shù)值~3＞3~6＞6~10＞10~14＞14~18＞18~24＞24~30＞30~40＞40~50＞50~65＞65~80＞80~100＞100~120＞120~140＞140~160注：源自《實(shí)用注塑成型及模具設(shè)計(jì)》P41表215（+）號(hào)，用于基準(zhǔn)軸取負(fù)（－）號(hào)。還要感謝洛陽(yáng)理工學(xué)院圖書館及圖書館熱情的管理員為我提供豐富的參考資料。同時(shí)也讓我明白了，學(xué)習(xí)就要學(xué)會(huì)深入，不要三心二意，要學(xué)會(huì)細(xì)心，要有耐心，否則一無所成?，F(xiàn)在想來，在導(dǎo)師的攙扶下走過的這半年做設(shè)計(jì)的過程，自己還真的長(zhǎng)進(jìn)不少，王老師，謝謝您！畢業(yè)設(shè)計(jì)是溫故而知新，和不斷提升的過程。此后王老師又不斷地為我解決設(shè)計(jì)中遇到的各類問題，在畫圖紙以及寫論文的時(shí)候，王老師又為我改出圖紙中的各處錯(cuò)誤。這幾個(gè)月的設(shè)計(jì)，時(shí)時(shí)出現(xiàn)問題和疑問，但是我還是感覺到一定的成就感，心里也蠻高興的，這也是對(duì)我這段時(shí)間的回報(bào)吧！洛陽(yáng)理工學(xué)院畢業(yè)設(shè)計(jì)論文謝 辭首先感謝我的導(dǎo)師王雅紅老師，她的耐心和博學(xué)多才讓我佩服。在設(shè)計(jì)的過程中我逐漸對(duì)模具有了更加深刻的認(rèn)識(shí)和了解，在剛接觸這門學(xué)科時(shí)，我對(duì)很多東西都不了解，就連基本的動(dòng)模板，定模板、凸模、凹模、定模板座、動(dòng)模板座都不知道是什么，經(jīng)過這一段時(shí)間的學(xué)習(xí)，我開始感覺到模具注塑模具也沒有想象中的難了，在學(xué)習(xí)注射模具時(shí)，由于塑料成型模具對(duì)塑件的材料也有很多的要求，因此對(duì)于一些工業(yè)中常用材料的性質(zhì)也有了初步的認(rèn)識(shí)和了解。在做好注塑成型的準(zhǔn)備工作之后，接著介紹了模具設(shè)計(jì)的內(nèi)容，冷流道注塑模具無外乎包括四大系統(tǒng)：澆注系統(tǒng)、溫度調(diào)節(jié)系統(tǒng)、頂出系統(tǒng)和機(jī)構(gòu)系統(tǒng)（其實(shí)也可以歸為頂出系統(tǒng)，該系統(tǒng)如斜導(dǎo)柱、滑塊和開閉器等）。.29 結(jié)　論本設(shè)計(jì)首先說明了塑料工業(yè)的重要地位和當(dāng)今注塑模具的現(xiàn)狀，隨著經(jīng)濟(jì)的發(fā)展，塑料工業(yè)將繼續(xù)呈現(xiàn)蓬勃發(fā)展之勢(shì)。 排氣系統(tǒng)由于塑件的尺寸適中，為薄殼型塑件，模具型腔空間較小，排氣量不大。設(shè)計(jì)時(shí)應(yīng)首先根據(jù)PVC塑料的成型溫度和注射量進(jìn)行熱平衡計(jì)算，再確定冷卻水道的尺寸和位置。在模具分型時(shí)，注射凝料從定模澆口套中被拉出，最后推出機(jī)構(gòu)開始工作，將塑件和澆注系統(tǒng)凝料一起推出模外。冷料穴的作用是 容納澆注系統(tǒng)流道中料流的前鋒冷料,以免這些冷料進(jìn)入型腔。圖64 分流道的截面形狀本模具只有一級(jí)分流道，半徑取4mm，分流道在定模板上銑削加工形成。4）澆注系統(tǒng)的主流道主流道上端直徑為5mm,下端直徑取8mm，高度為75mm,錐角4176。拉料桿的結(jié)構(gòu)： 圖63 拉料桿的結(jié)構(gòu)材料選用45鋼，淬火處理HRC40～45。 圖62 定位圈的結(jié)構(gòu)設(shè)計(jì)3）拉料桿的設(shè)計(jì)澆口套出料口直徑為8mm，取拉料桿的直徑與出料口相等8mm。 定位圈的固定使用M6內(nèi)六角螺釘。 圖61 澆口套的結(jié)構(gòu)2）定位圈的設(shè)計(jì)XS－ZY－500注射機(jī)的固定模板上定位孔直徑為150mm。澆口套外徑取24mm。澆口套凹球面半徑取20mm，深度取3mm。澆注系統(tǒng)零件的設(shè)計(jì) 澆口套的結(jié)構(gòu) 使用XS－ZY－500注射機(jī)時(shí)定位孔直徑為150mm，與澆口套下部尺寸相差較大，所以選用定位圈與澆口套分離的結(jié)構(gòu)。 澆注系統(tǒng)的設(shè)計(jì)塑件采用直接澆口成型 分流道采用梯形截面流道，梯