【正文】 的尺寸和表面光潔度的，后刀面磨損可能造成尺寸不合格的產(chǎn)品而且表面光潔度也差。在大多數(shù)實(shí)際切削條件下，由于主前刀面先于副前刀面磨損，磨損到達(dá)足夠大時(shí)，刀具將實(shí)效，結(jié)果是制成不合 格零件。 由于刀具表面上的應(yīng)力分布不均勻，切屑和前刀面之間滑動(dòng)接觸區(qū)應(yīng)力，在滑動(dòng)接觸區(qū)的起始處最大，而在接觸區(qū)的尾部為零，這樣磨蝕性磨損在這個(gè)區(qū)域發(fā)生了。這是因?yàn)樵谇邢骺ㄗ^(qū)附近比刀刃附近發(fā)生更嚴(yán)重的磨損，而刀刃附近因切屑與前刀面失去接觸而磨損較輕。這結(jié)果離切削刃一定距離處的前刀面上形成麻點(diǎn)凹坑，這些通常被認(rèn)為是前刀面的磨損。通常情況下，這磨損橫斷面是圓弧形的。在許多情況中和對(duì)于實(shí)際的切削狀況而言，前刀面磨損比起后刀面磨損要輕，因此后刀面磨損更普遍地作為刀具失效的尺度標(biāo)志。然而因許多作者已經(jīng)表示過(guò)的那樣在增 加切削速度情況下，前刀面上的溫度比后刀面上的溫度升得更快，而且又因任何形式的磨損率實(shí)質(zhì)上是受到溫度變化的重大影響。因此前刀面的磨損通常在高速切削時(shí)發(fā)生的。 刀具的主后刀面磨損帶的尾部是跟未加工過(guò)的工件表面相接觸，因此后刀面磨損比沿著磨損帶末端處更為明顯，那是最普通的。這是因?yàn)榫植啃?yīng)，這像未加工表面上的已硬化層，這效應(yīng)是由前面的切削引起的工件硬化造成的。不只是切削，還有像氧化皮，刀刃產(chǎn)生的局部高溫也都會(huì)引起這種效應(yīng)。這種局部磨損通常稱作為凹坑性磨損，而且偶爾是非常嚴(yán)重的。盡管凹坑的出現(xiàn)對(duì)刀具的切削性質(zhì)無(wú)實(shí)質(zhì) 意義的影響，但凹坑常常逐漸變深，如果切削在繼續(xù)進(jìn)行的話，那么刀具就存在斷裂的危機(jī)。 如果任何進(jìn)行性形式 的磨損任由繼續(xù)發(fā)展，最終磨損速率明顯地增加而刀具將會(huì)有摧毀性失效破壞，即刀具將不能再用作切削，造成工件報(bào)廢，那算是好的，嚴(yán)重的可造成機(jī)床破壞。對(duì)于各種硬質(zhì)合金刀具和對(duì)于各種類型的磨損，在發(fā)生嚴(yán)重失效前，就認(rèn)為已達(dá)到刀具的使用壽命周期的終點(diǎn)。然而對(duì)于各種高速鋼刀具，其磨損是屬于非均勻性磨損，已經(jīng)發(fā)現(xiàn)：當(dāng)其磨損允許連續(xù)甚至到嚴(yán)重失效開(kāi)始，最有意義的是該刀具可以獲得重磨使用，當(dāng)然，在實(shí)際上，切削時(shí)間遠(yuǎn)比使用到失 效的時(shí)間短。以下幾種現(xiàn)象之一均是刀具嚴(yán)重失效開(kāi)始的特征：最普遍的是切削力突然增加，在工件上出現(xiàn)燒損環(huán)紋和噪音嚴(yán)重增加等。 自動(dòng)夾具設(shè)計(jì) 用做裝配設(shè)備的傳統(tǒng)同步夾具把零件移動(dòng)到夾具中心上，以確保零件從傳送機(jī)上或從設(shè)備盤(pán)上取出后置于已定位置上。然而在某些應(yīng)用場(chǎng)合、強(qiáng)制零件移動(dòng)到中心線上時(shí)，可能引起零件或設(shè)備破壞。當(dāng)零件易損而且小小振動(dòng)可能導(dǎo)致報(bào)廢時(shí)，或當(dāng)其位置是由機(jī)床主軸或模具來(lái)具體時(shí)，再或者當(dāng)公差要求很精密時(shí)，那寧可讓夾具去適應(yīng)零件位置，而不是相反。為著這些工作任務(wù)，美國(guó)俄亥俄州 Elyria 的 Zaytran 公司已經(jīng)開(kāi)發(fā)了一般性功能數(shù)據(jù)的非同步西類柔順性?shī)A具。因?yàn)閵A具作用力和同步化裝置是各自獨(dú)立的，該同步裝置可以用精密的滑移裝置來(lái)替換而不影響夾具作用力。夾具規(guī)格范圍是從 英寸行程， 5 英鎊夾緊力到 6 英寸行程、 400 英寸夾緊力。 現(xiàn)代生產(chǎn)的特征是批量變得越來(lái)越小而產(chǎn)品的各種規(guī)格變化最大。因此，生產(chǎn)的最后階段，裝配因生產(chǎn)計(jì)劃、批量和產(chǎn)品設(shè)計(jì)的變更而顯得特別脆弱。這種情形正迫使許多公司更多地致力于廣泛的合理化改革和前面提到過(guò)情況那樣裝配自動(dòng)化。盡管柔性?shī)A具的發(fā)展很快落后與柔性運(yùn)輸處理裝置的發(fā)展，如落后于工業(yè)機(jī)器人 的發(fā)展，但仍然試圖指望增加夾具的柔順性。事實(shí)上夾具的重要的裝置 —— 生產(chǎn)裝置的專向投資就加強(qiáng)了使夾具更加柔性化在經(jīng)濟(jì)上的支持。 根據(jù)它們?nèi)犴樞裕瑠A具可以分為：專用夾具、組合夾具、標(biāo)準(zhǔn)夾具、高柔性?shī)A具。柔性?shī)A具是以它們對(duì)不同工件的高適應(yīng)性和以少更換低費(fèi)用為特征的。 結(jié)構(gòu)形式可變換的柔性?shī)A具裝有可變更結(jié)構(gòu)排列的零件（例如針形頰板，多片式零件和片狀頰板），標(biāo)準(zhǔn)工件的非專用夾持或夾緊元件（例如：?jiǎn)?dòng)標(biāo)準(zhǔn)夾持夾具和帶有可移動(dòng)元件的夾具配套件），或者裝有陶瓷或硬化了的中介物質(zhì)（如：流動(dòng)粒子床夾具和熱夾具緊夾具）。為了生產(chǎn) ，零件要在夾具中被緊固，需要產(chǎn)生夾緊作用，其有幾個(gè)與夾具柔順性無(wú)關(guān)的步驟： 根據(jù)被加工的即基礎(chǔ)的部分和工作特點(diǎn)，確定工件在夾具中的所需的位置，接著必須選擇若干穩(wěn)定平面的組合，這些穩(wěn)定平面就構(gòu)成工件被固定在夾具中確定位置上的夾持狀輪廓結(jié)構(gòu)，均衡所有各力和力矩，而且保證接近工件工作特點(diǎn)。最后，必須計(jì)算、調(diào)整、組裝可拆裝的或標(biāo)準(zhǔn)夾具元件的所需位置，以便使工件牢牢地被夾緊在夾具中。依據(jù)這樣的程序，夾具的輪廓結(jié)構(gòu)和裝合的規(guī)劃和記錄過(guò)程可以進(jìn)行自動(dòng)化控制。 結(jié)構(gòu)造型任務(wù)就是要產(chǎn)生若干穩(wěn)定平面的組合，這樣在這些平面上的各 夾緊力將使工件和夾具穩(wěn)定。按慣例，這個(gè)任務(wù)可用人 — 機(jī)對(duì)話即幾乎完全自動(dòng)化的方式來(lái)完成。一人 — 機(jī)對(duì)話即以自動(dòng)化方式確定夾具結(jié)構(gòu)造型的優(yōu)點(diǎn)是可以有組織有規(guī)劃進(jìn)行夾具設(shè)計(jì)，減少所需的設(shè)計(jì)人員，縮短研究周期和能更好地配置工作條件。簡(jiǎn)言之，可成功地達(dá)到顯著提高夾具生產(chǎn)效率和效益。 在充分準(zhǔn)備了構(gòu)造方案和一批材料情況下，在完成首次組裝可以成功實(shí)現(xiàn)節(jié)約時(shí)間達(dá) 60%。 因此夾具機(jī)構(gòu)造型過(guò)程的目的是產(chǎn)生合適的編程文件。 Foreign language translation machinery shaft and gear design and application Abstract In the traditional mechanical and modern machinery in the important position of gear and shaft is unshakable. Gears and shafts to the main spindle box installed in the transmission direction of the force. Through the processing can be divided into a number of models were used in many occasions. So we gear and shaft of understanding and knowledge must be multilevel multifaceted. Keywords: Gear。 axis In the stress analysis of spur gear, is assumed to act in a single plane. We will study the threedimensional coordinates of the gear forces. Thus, in the case of helical gears, the teeth are not parallel to the axis of rotation. In the case of bevel gears, the rotational axes are not parallel to each other. As we discussed, there are other reasons to learn and master. Helical gears are used to pass the motion between parallel axes. Angle of each gear are the same, but one must be rightlateral oblique teeth, while the other must be leftlateral oblique teeth. Tooth shape is a helical surface splash. If one is cut into a parallelogram (rectangle) surrounded by the gear cylinder of paper, the paper printed side edge angle of the tooth bees slash. If I start this piece of paper, in the blood blade edge angle on each point occurred on the involute curve. Spur gear teeth is that the initial contacts across the entire tooth surface and extend to the line. Helical gear tooth is the point of initial contact, when the teeth meshing into more, it bees line. In spur gears, the contact is parallel to the axis of rotation. Helical gears in the first diagonal line across the tooth surface. It is the gradual meshing gears and smooth teeth from one tooth to another, passing movement that makes highspeed helical gears under heavy load with the ability to transmit motion smoothly. Helical gear shaft bearings to withstand radial and axial force. When the axial thrust of a big change or due to other reasons, have some impact, then you can use the herringbone gear. Double helical gear (herringbone gear) is mounted side by side with the reverse on the same axis is equivalent to two helical gears. They have the opposite effect of axial thrust, thus eliminating axial thrust. When two or more unidirectional bevel gear to be on the same axis, the gear39。s tooth should be selected so that a minimum of axial thrust. Crossed helical gears or helical gears, they are neither intersecting nor parallel to the shaft centerline. Crossed helical gears point contact between each other, it39。s runin with the gear and into a line contact. So they can only transfer the load and is mainly used for small equipment in, and certainly can not remend the use of the power transmission. Crossed helical gears and helical gears to be installed between the kneading after each other before, there is no difference. They are manufactured in the same way. A pair of meshing of crossed helical gears typically have the same tooth, that is Lgear driven gear meshing with the right hand. In the crossed helical gear design, when the helix angle equal to the minimum when the sliding velocity generated. However, when the helix angle is not equal, if the two gears with the same tooth, then apply for a large bevel gear gear. Worm and crossed helical gears similar. The worm pinion has a smaller number of teeth, usually one to four teeth, because they are pletely wrapped around the cylindrical section, so they are referred to as thread teeth. Its called the worm gear to match, not a true helical worm gear. Worm and worm gear is usually u