【正文】 Machine Tools The work process of NC is shown in the right figure. Part drawing Part program Control puter Servodrive unit Machine tool Part Next the part program is transferred into the control puter(MDI).the puter converts each mand into the signal that the servodrive unit needs . Chapter 1 INTRODUCTION TO NUMERICAL CONTROL Basic Components of NC Machine Tools The work process of NC is shown in the right figure. Part drawing Part program Control puter Servodrive unit Machine tool Part At last , the servodrive unit drives the machine tool to manufacture the finished part . Chapter 1 INTRODUCTION TO NUMERICAL CONTROL Basic Components of NC Machine Tools A typical NC machine tool has five fundamental units: (1)the input media。 (3)the servodrive unit。 (5)the mechanical machine tool unit . Chapter 1 INTRODUCTION TO NUMERICAL CONTROL Basic Components of NC Machine Tools The general relationship among the five ponents is illustrated in the below. . Chapter 1 INTRODUCTION TO NUMERICAL CONTROL Basic Components of NC Machine Tools The input media contains the program of instructions, it is the detailed stepbystep mands that direct the actions of the machine tool。 (2)The type of servodrive system。 (2) Continuous (Contouring)path control system。 however, its implementation costs are higher. . Chapter 1 INTRODUCTION TO NUMERICAL CONTROL Types of NC ServoDrive System ClosedLoop ServoDrive Position pare circuit Speed control circuit Worktable Instruction Speed feedback signal Position feedback signal Leadscrew Servomotor . Chapter 1 INTRODUCTION TO NUMERICAL CONTROL Application of CNC The applications of CNC are divided into two categories: (1)Machine tool applications。 thus twoaxis control is laser cutting machines can cut holes in preformed sheet metal stock, requiring four or five axis control. . Chapter 1 INTRODUCTION TO NUMERICAL CONTROL Application of CNC NonMachine Tool Application Tube bending machine (數控彎管機 ) Automatic tube bending machines are programmed to control the location and the angle of the applications include frames of bicycles and motorcycles. . Chapter 1 INTRODUCTION TO NUMERICAL CONTROL FEATURES OF NC AND ITS APPLICATIONAREAS Advantages and Disadvantages of NC NC has many benefits and advantages over manual production methods, but NC is more sophisticated technology than conventional production methods. . Chapter 1 INTRODUCTION TO NUMERICAL CONTROL Advantages and Disadvantages of NC Advantages of NC (1)Greater accuracy and repeatability (2)More plex part geometries are possible (3)Nonproductive time is reduced (4)Lower scrap rates (5)Inspection requirements are reduced (6)Engineering changes can be acmodated more gracefully . Chapter 1 INTRODUCTION TO NUMERICAL CONTROL Advantages and Disadvantages of NC Advantages of NC (7)Simpler fixtures are needed (8)Shorter manufacturing lead times (9)Reduced parts inventory (10)Less floor space required (11)Operator skilllevel requirements are reduced . Chapter 1 INTRODUCTION TO NUMERICAL CONTROL Advantages and Disadvantages of NC Disadvantages of NC (1)Higher investment cost (2)Higher maintenance effort (3)Part program (4)Higher utilization of NC equipment . Chapter 1 INTRODUCTION TO NUMERICAL CONTROL Application Areas for NC Machine Tools NC is best suited to relatively low volume runs of plex and varied ponents .NC can also be used to produce large numbers of plex ponents and /or small numbers simple ones. 謝謝觀看 /歡迎下載 BY FAITH I MEAN A VISION OF GOOD ONE CHERISHES AND THE ENTHUSIASM THAT PUSHES ONE TO SEEK ITS FULFILLMENT REGARDLESS OF OBSTACLES. BY FAITH I BY FAITH