摘 要
数控机床加工零件时，首先应编制零件的加工程序，这是数控机床的工作指令。将加工程序输入到数控装置，再由数控装置控制机床主运动的变化、起停，进给运动的方向、速度和位移量以及其它如刀具选择交换、工件夹紧松开和冷却润滑的开、关等动作，使刀具与工件及其它辅助装置严格的按照加工程序规定的顺序、轨迹和参数进行工作，从而加工出符合要求的零件。
主传动系统设计主要是指运用转速图的基本原理，拟定满足转速数列经济的，合理的传动系统方案。确定主要传动件的空间布置。其主要内容包括：选择变速组及其传动的副数，确定各变速组中的传动比 ，计算齿轮齿数和皮带轮直径，以及设计主要传动件的空间布置，轴向定位及其结构尺寸。主传动系统一般由动力源（如电动机），变速装置及执行件（如主轴，工作台），以及开停，换向和制动机构等部分组成。动力源给执行件提供动力，变速装置传递动力以及变换运动速度，执行件执行机床所需的运动，完成旋转或直线运动。
本次设计主要了解C618数控车床发展；利用所学知识对其分析与研究，了解国内外C618数控车床发展动态；对C618数控车床主传动系统的结构设计；绘制零件图及装配图。
关键词：C618；数控车床；主传动；结构设计
ABSTRACT
When NC machine tools process parts，the machining program of parts should be compiled first，which is the working instruction of NC machine tools. The machining program is input into the NC device，and then the NC device controls the change，start and stop of the main motion of the machine tool，the direction，speed and displacement of the feed movement，and other actions such as tool selection and exchange，workpiece clamping and loosening and cooling lubrication，so that the tool and workpiece and other auxiliary devices work strictly according to the sequence，trajectory and parameters specified in the machining procedure，so as to process the parts that meet the requirements.
The main transmission system design mainly refers to using the basic principle of the speed chart to draw up a reasonable transmission system scheme which satisfies the economy of the speed sequence. Determine the spatial arrangement of the main transmission parts. The main contents include: selecting the number of transmission pairs of the transmission group and its transmission，determining the transmission ratio in each transmission group，calculating the number of gear teeth and the diameter of the belt pulley，and designing the spatial arrangement of the main transmission parts，axial positioning and its structural dimensions. The main transmission system is generally composed of power source (such as motor)，variable speed device and actuator (such as spindle，worktable)，as well as on and off，reversing and braking mechanism. Power supply power to actuator，variable speed Set transfer power as well as change the speed of motion，the actuator to perform the machine required motion，complete rotation or linear motion.
This design mainly understand the development of C618 CNC lathe；use the knowledge to analyze and study it，understand the development trends of C618 CNC lathe at home and abroad；design the structure of the main transmission system of C618 CNC lathe；draw part drawings and assembly drawings.
Keywords: C618；CNC lathe；Main transmission；Structural design
目 录
1绪论 1
1.1选题背景及意义 1
1.2发展现状 2
1.3研究主要内容 2
2 C618数控车床的整体布局 3
2.1 C618简介 3
2.2 床身设计 3
2.3 回转刀架设计 4
2.4 矩形滑动导轨设计 5
2.5平板链式排屑装置设计 5
2.6进给传动系统设计 6
2.7主轴箱设计 6
3 C618数控车床主传动系统设计 8
3.1 拟定传动方案 8
3.2 选择电机 9
3.3 计算各轴转速、功率和转矩 12
3.4 传动图设计 13
3.5 转速图设计 14
4 C618数控车床相关部件设计及选择 15
4.1轴系部件的结构设计 15
4.1.1 I轴结构设计 15
4.1.2 II轴结构设计 19
4.2电磁摩擦离合器的计算和选择 25
4.3键和圆螺母的选择 29
4.4主轴结构设计 30
4.5编码器的选择与安装 34
4.6绘制主传动系统总装图 36
5总结与展望 37
致 谢 38
参考文献 39
