摘要

本次设计主要是普通立式铣床的经济型数控改造设计，在本设计中，采用AT89C51、2764、6264、8155等芯片扩展成简单的开环单片机控制系统，通过铣削参数的计算确定步进电机。软件采用模块式，主要包括主程序模块、键盘显示模块、串行通信模块、凸轮程序处理模块、报警中断模块等。有键盘输入用户加工程序，存入外部程序存储器（2764），根据加工程序内容控制步进电机驱动工作台的径向（X向）和周向（Y向）联动，从而加工出相应的凸轮轮廓。同时，设计中也考虑到系统的精确性和稳定性，采用双片齿轮错齿法调整滚珠丝杠的轴向间隙，选用光电隔离电路去除强电干扰，选择大功率场效应晶体管斩波驱动电路实现脉冲的放大。

本设计造价低、适应能力强、应用范围广。采用本机床加工可大幅度降低工人劳动强度，有效提高加工生产率和提高工件精度。

关键词：数控技术，数控改造，单片机，，机床改造，凸轮加工

ABSTRACT

The design is General economic vertical milling machine design of NC, in this design, use of AT89C51, 2764,6264,8155, and other chip expansion into simple open-loop control system microcontroller, through the milling parameters Calculation determine stepper motor. Use of modular software, including the main program modules, keyboard modules, serial communication module, Cam process of the module, the police interrupted module. A keyboard input users processing procedures, into the external program memory (2764), in accordance with procedures for processing the content control of the stepper motor-driven table radial (X to) and the Zhou (Y to) linked to processing the corresponding cam Contour. At the same time, also taking into account the design of the system accuracy and stability of a dual-gear tooth wrong ball screw adjustment of the axial gap, the choice of optoelectronic circuits to remove segregation-interference, select high-power field-effect transistor chopper Driver circuit pulse amplification.

The design of low cost, strong adaptability and wide application. Using this machine tool workers can be significantly reduced labor intensity, effectively enhance the productivity and improve processing accuracy of the workpiece.

Keywords: NC, NC transformation, SCM, machine transformation, processing Cam

目 录

第1章 绪论 ································································ 1

1.1 课题背景 ···················································································2 1.2 现实意义 ····················································································2 1.3 设计任务 ····················································································2 1.4 总体设计方案分析 ·······································································2 1.5 总体设计方案确定 ·······································································2 1.5.1 伺服系统 ·················································································2 1.5.2 控制信号 ·················································································2 1.5.3 辅助功能 ·················································································2

第2章 步进电机的确定 ··················································· 1

2.1 步进电机的选用 ··········································································2 2.1.1 铣削用量 ·················································································2 2.1.2切削层参数 ···············································································2 2.1.3 铣削力和功率 ···········································································2 2.1.4计算 ························································································2

第3章 消隙方法与预紧 ··················································· 2

3.1 消隙方法 ····················································································2 3.1.1 偏心轴套调整法 ······································································2 3.1.2 锥度齿轮调整法 ······································································2 3.1.3 双片齿轮错齿调整法 ································································2 3.2 预紧 ··························································································2

第4章 步进电机接口电路及驱动 ········································ 1 第5章 数控系统设计······················································ 1

5.1 确定机床控制系统方案 ·································································2 5.2 主要芯片配置 ·············································································2 5.2.1 主要芯片选择 ·········································································2 5.2.2 主要管脚功能 ·········································································2 5.2.3 EPROM的选用 ······································································2

5.2.4 RAM的选用 ··········································································2 5.2.5 8031存储器及I/O的扩展 ··························································2 5.2.6 8155工作方式查询 ··································································2 5.2.7 状态查询 ···············································································2 5.2.8 8155定时功能 ········································································2 5.2.9 芯片地址分配 ·········································································2 5.3 键盘设计 ····················································································2 5.3.1 键盘定义及功能 ······································································2 5.3.2 键盘程序设计 ·········································································2 5.4 显示器设计·················································································2 5.4.1 LED的显示原理 ······································································2 5.4.2 LED显示器与8155的连接 ························································2 5.4.3 显示缓冲区 ············································································2 5.5 光电隔离电路 ·············································································2 5.6 越界报警电路 ·············································································2 5.6.1 主要电子器件 ·········································································2 5.7 总体程序控制 ·············································································2 5.7.1 数据处理程序 ·········································································2 5.7.2 串行通信的软件设计 ································································2 5.7.3 加工程序的设计 ······································································2 5.7.4 流程图 ··················································································2 5.7.5 总程序 ··················································································2

结论 ·········································································· 1 参考文献 ···································································· 1 致谢 ·········································································· 1