UNIT 1 INTRODUCTION TO NC MACHINE （1号机组介绍数控机床）.pdf

Introduction to UNIT 1 INTRODUCTION TO NC MACHINE NC Machine Tools TOOLS Structure 1.1 Introduction Objectives 1.2 NC Machines 1.2.1 Types of NC Machine 1.2.2 Controlled Axes 1.2.3 Basic Components of NC Machines 1.2.4 Problems with Conventional NC 1.3 Principles of NC Machines 1.4 Summary 1.5 Answers to SAQs 1.1 INTRODUCTION NC machines, advantages of NC machines, Types of NC systems, Controlled axes, Basic Components of NC Machines, Problems with Conventional NC and Principles of NC Machines are described in this Unit. Objectives After studying this unit, you should be able to understand  ,  ,  , and  . 1.2 NC MACHINES Controlling a machine tool by means of prepared program, which consists of blocks, or series of numbers, is know as numerical control (NC). In manufacturing of more complicated parts, the system has to calculate automatically additional data points, which is done by means of an interpolator. Numerical Control (NC) refers to the method of controlling the manufacturing operation by means of directly inserted coded numerical instructions into the machine tool. It is important to realize that NC is not a machining method; rather, it is a concept of machine control. Although the most popular applications of NC are in machining, NC can be applied to many other operations, including welding, sheet metalworking, riveting, etc. NC machines are method of automation, where automation of medium and small volume production is done by some controls under the instructions of a program. Various definitions of NC are : A system in