手柄軸工藝及夾具設(shè)計(jì)-資料下載頁(yè)
2024-11-03 16:57本頁(yè)面
【導(dǎo)讀】題目所既定的零件為輸出軸，其主要作用，一是傳遞轉(zhuǎn)矩，使主軸獲得旋轉(zhuǎn)的動(dòng)力；二是工作過(guò)程中經(jīng)常承受載荷；三是支撐傳動(dòng)零部件。要求不高，位置要求較嚴(yán)格，表現(xiàn)在φ40的右端面、φ20圓柱面。熱處理方面需要調(diào)質(zhì)處理，到200HBS，保持均勻。通過(guò)分析該零件，其布局合理，方便加工，我們通過(guò)徑向夾緊可保證其加工要求，整個(gè)圖面清晰，尺寸完整合理，能夠完整表達(dá)物體的形狀和大小，符合要求。毛坯種類(lèi)的選擇決定與零件的實(shí)際作用，材料、形狀、生產(chǎn)性質(zhì)以及在生產(chǎn)中獲得可能性，毛坯的制造方法主要有以下幾種：1、型材2、鍛造3、鑄造4、焊接5、其他毛坯。鋼質(zhì)模鍛件的公差及機(jī)械加工余量按GB/T12362-2003確定。要確定毛坯的尺寸公差及機(jī)械加工余量，應(yīng)先確定如下各項(xiàng)因素：。零件表面粗糙度由零件圖知除錐面及右端面=.。根據(jù)鍛件質(zhì)量、零件表面粗糙度、形狀復(fù)雜系數(shù)查表5-9，～，～，～，～。，余量要適當(dāng)增大。如精度和表面粗糙度要求，主要目標(biāo)是全面保證加工質(zhì)量。
【正文】 ial, usually carbon. The electrode, made to the shape of the cavity required, and the workpiece are both submerged in a dielectric fluid, which is generally a light lubricating oil. This dielectric fluid should be a nonconductor (or poor conductor) of electricity. A servo mechanism maintains a gap of about to in. ( to mm) between the electrode and the work, preventing them from ing into contact with each other. A direct current of low voltage and high amperage is delivered to the electrode at the rate of approximately 20 000 hertz (Hz). These electrical energy impulses bee sparks which jump the dielectric fluid. Intense heat is created in the localized area of the park impact, the metal melts and a small particle of molten metal is expelled from the surface of the workpiece . The dielectric fluid, which is constantly being circulated, carries away the eroded particles of metal and also assists in dissipating the heat caused by the spark.In the last few years, major advances have been made with regard to the surface finishes that can be produced. With the low metal removal rates, surface finishes of 2 to 4 um. ( to ) are possible. With high metal removal rates finishes of 1 000uin. (25um) are produced.The type of finish required determines the number of amperes which can be used, the capacitance, frequency, and the voltage setting. For fast metal removal (roughing cuts), high amperage, low frequency, high capacitance, and minimum gap voltage are required. For slow metal removal (finish cut) and good surface finish, low amperage, high frequency, low capacitance, and the highest gap voltage are required.Electrical discharge machining has many advantages over conventional machining processes.1. Any material that is electrically conductive can be cut, regardless of its hardness. It is especially valuable for cemented carbides and the new supertough spaceage alloys that are extremely difficult to cut by conventional means.2. Work can be machined in a hardened state, thereby overing the deformation caused by the hardening process.3. Broken taps or drills can readily be removed from workpieces. 4. It does not create stresses in the work material since the tool (electrode) never es in contact with the work.5. The process is burrfree.6. Thin, fragile sections can be easily machined without deforming.7. Secondary finishing operations are generally eliminated for many types of work.8. The process is automatic in that the servomechanism advances the electrode into the work as the metal is removed.9. One person can operate several EDM machines at one time.10. Intricate shapes, impossible to produce by conventional means, are cut out of a solid with relative ease.11. Better dies and molds can be produced at lower costs.12. A die punch can be used as the electrode to reproduce its shape in the matching die plate, plete with the necessary clearance. 23
試題試卷相關(guān)推薦
鄂ICP備17016276號(hào)-1