裝配圖環(huán)形罩殼件落料、拉深、成形、修邊復(fù)合模設(shè)計(jì)(有cad圖)
裝配圖環(huán)形罩殼件落料、拉深、成形、修邊復(fù)合模設(shè)計(jì)(有cad圖),裝配,環(huán)形,罩殼,件落料,成形,復(fù)合,設(shè)計(jì),cad
Basic Machine Tool ElementsMost machine tools are constructed by using two or more components. These components , although they may have different function in such as a lathe , mill or drill press , have common characteristicsBecause of the demand for metal removal machines such as lathes , machining centers ,milling machines ,grinders , and the many others shown throughout this book , there has been continuous development in flexible machining centers .the mass-produced and special machine tools are constructed of basic elements . this chapter describes those elements .Important requirements for machine tool structures include rigidity, shape , operator and part accessibility , ease of chip removal , and safety . In terms of machine tool performance , static and precision . Stability of the machine structure is necessary to appreciate the breadth of modern machining methods in the manufacture of products .Structures For Cutting MachinesCastings , forgings , and hot-or cold-formed shapes usually require machining .The variety of sizes , shapes , and materials calls for diversity in machining.Machine tools differ not only in the number of cutting edges they employ , but also in the way the tool and workpiece are moved in relation to each other . In some machines (vertical machining centers , drill presses , boring machines , milling machines, shapers, and grinders) the workpiece remains virtually motionless and the tool moves . in others (planers , lathes , and boring mills ) the tool is virtually fixed and the workpiece moves. But it should be pointed out that seldom are these simple elements applied without modification . The dingle-piont tool-shaping machines are the easiest to visualize , the lathe and the boring machine are kinematic inversions employing the single-point tool . the work rotates in the lathe, but the cutting toll is stationary . In the boring machine the tool rotates while the work is stationary . Although the lathe tool and the boring machine worktable are not truly stationary , this is overlooked for the moment . To feed a tool carriage past rotating work is usually more acceptable than to feed rotating work with headstock and supports past a stationary tool post . The shaper and planer use single-point cutting tool . The smaller workpiece is more efficiently machined on the shaper than on the planer . The general appearance of the machine is changed by reversing the kinematic relationship of work and tool . However , the cutting action principle is identical .With the introduction of the milling cutter by Eli Whitney in the early 1800s , the rotating tool was used only as a boring tool . But Whitney gave it a new application . The milling cutter was no longer used for cutting keyways , slitting ,sawing , slab and face milling , gear cutting , and shaping irregularly-formed pieces . Use of the rotating tool combined with traversing work .The cylindrical grinder adopts motions of the lathe and boring machine except for the substituting of rotating tools (the grinding wheel ) for single-point tools . The characteristics of these basic cutting machines are listed in Tab . Tab Cutting and Feed Movement for Conventionnal MachinesMachineCutting MovementFeed Movement Types of Operation LatheWorkpiece rotates Tool and carriageCylindrical surface, drilling, boring , reamingBoring machineTool rotates Table Drilling , boring, reaming ,and facing planerTable traversesTool Flat surfaces(planning)ShaperTool traversesTableFlat surfaces(shaping)Horizontal MillingTool rotatesTableFlat surfaces, gears, cams, drilling, boringHorizontal boring machineTool rotatesTool traversesFlat surfacesCylindrical grinderTool (grinding wheel) rotatesTable and /or toolCylindrical surface(grinding)Drill pressTool rotatesTool Drilling boring facing and threadingSaw Tool Table and /or pieceCut offBroaching machine Tool Tool External and internal surfaces
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