华南理工大学《机械制造技术基础》chapter4-section3new.pptxVIP

4.3 Hole making machine tool and cutting tool Drilling machine (钻床) Boring machine (镗床) Broaching machine (拉床) Usually used hole making machine tools Usually used hole making cutting tools Twist drill (麻花钻) and “masses?drill” (群钻) Core drill (扩孔钻) Reamer (铰刀) Boring cutter (镗刀) Broaching cutter (拉刀) 4.3.1 Drilling machines Drilling machines can both enlarge and finish cutting of holes from a small fraction of a millimetre to hundreds of millimetres in diameter. Drilling machines are used for rough drilling holes. Main types: Vertical(立式） 、Radial（摇臂）、Deep hole drills（深孔）. The picture shows a typical Vertical Drilling machines . 深孔钻、深孔钻床、深孔加工机-台湾威鸿 BTA2500.flv Radial drill press Methods of Machining operations: Fig 3.29 4.3.2 Boring machine Boring is the operation that enlarges a pre-existed internal hole. Several machines have been developed that are specially adapted to boring work. . Main types of boring machines:Horizontal boring machine 、Jig boring machines and high accurate boring machine 镗床加工.flv Boring machine (镗床) Performance: big size, high accurate, different surfaces, high accurate relative position. Main motion: rotation of the boring cutterfeed motion: cutter or workpiece Jig boring machine (坐标镗床）: Very high accurate position. position accuracy is between 0.002~0.01mm Diamond boring machine diamond boring cutters used. 4.3.3 Drilling tools 瑞士米克朗疯狂微型钻头.flv 钻头是如何制作的.flv (1) Twist drill Structure of ordinary twist drill Tip angle—formed by two planes parallel with the two main cutting edges Chisel edge—center edge linking the two main cutting edges 1 Ordinary Twist drills（麻花钻） The main geometry for twist drill is: the helical angle ? (24~30), the tip angle 2?(118~130), rake angle ?, relief angle ? and wedge inclination angle Different types of twist drills adapted 2 Adapted twist drills 如何磨钻头.flv The quality of surface machined by twist drill The accuracy: IT11-IT12 The roughness: 50~12.5?m The range