本科毕业论文---数控加工中心自动换刀系统的研究外文翻译.doc

密级：

JINGGANGSHAN UNIVERSITY
外文翻译

题目 数控加工中心自动换刀系统的研究

学 院 机电工程学院
专 业 机械设计制造及其自动化
班 级 机制11(本1)
学 号
姓 名
指导教师
起讫时间 2014.11——2015.5

教 务 处 印 制

16
机电工程学院 机械设计制造及其自动化专业 外文翻译
Machinery,2011,12(04)
Research on the automatic tool changer system of the manching center

ZHENG Xin-wu,ZHANG Ming-zhong,LI Chun-mu,LI Yin,CHEN Yong-ming
(Department of Mechanical & Electrical Engineering,Xiamen University,Xiamen361005,China)

Abstract：The automatic tool changer(ATC),which includes a magazine, a tool changer and a control system, is one of the key compoments of the machining center (MC), General issues of the ATC, however, are its slowness and low stability during tool changes and the complexity of control system programming. To solve those problems, one type of software and its internal PLC technology were inverstigated. Based on an analysis of the fundamental structure and operating principle of the ATC system and a research of the control procedure of the “disc with arm”-type ATC,the PLC program and macro programs combined with ServoWorks CNC technology were developed.Finally, it was shown that newly designed control system can complete the whole process of changing tools in 4 to 6 seconds on the YY-1060 vertical MC. The results indicate that the process is rapid, accurate and reliable enough to completely meet the practical requirements.
Keywords: machining center(MC); automatic tool changer(ATC); programmable logic controller(PLC)

1. Introduction
Using knife library (MAG) automatic tool change is the way of tool change, is widely used in machining center independent knife library vastly increases the storage quantity of cutting tool, which helps to expand the function of machine tool, and can be well isolated interference of various kinds of factors affecting the machining accuracy.Processing center of the library types are: a knife disc tool library and chain tool library.Library change tool way according to the presence of manipulator, tool change process into a manipulator tool change and no manipulator tool change.This study in order to YY - 1060 vertical machining center is equipped with DEX - A402 disc tool library manipulator automatic tool change mechanism as the object, study of automatic tool changer (ATC) system.
Programmable controller (PLC) is the core part of automatic tool change system.At present, the domestic control of the automatic tool change more than the traditional PLC (hereinafter referred to as hard PLC) and single chip microcomputer, such as mitsubishi FX series PLC, Siemens S7-200 series PLC, AT98C51 microcontroller.Hard PLC control method without special instructions of the tool, you need to write complex cutter PLC program, as well as simplify the process of nc programming by macro program;Adopt single chip microcomputer control circuit structures, complex, the system stability is low, programming complex.This research adopts the LadderWorks is a kind of built-in PLC system software based on the technology of ServoWorks type, can be between CNC rapid internal signal transmission.
2. Library structure and tool change movement
Automatic tool change main components include: motor, CAM, tool pot, dao library motor, cup, brake, pine clip round tool, the origin signal, etc.DEX - A402 automatic tool change is shown in figure 1.

Fig.1.Automatic tool change Fig.2.Sword arm action
Sword arm action driven by stepping motor, tool change action points 4 steps to complete.Single sword arm motor direction of rotation, through the automatic tool change mechanism of CAM mechanism to control the sword arm and reversing, the drive mode improves the sword arm rotation Angle precision, simplify the control of the motor at the same time.Sword arm movement of the specific process as shown in figure 2.
3. Transfer instructions
CNC programming instruction by T, M instructions to complete the automatic tool change action, tool change instruction decoded by the internal system, the target tool, and macro instruction, translated into the corresponding binary number saved to the system specified in the register.ServoWorksPLC system T instruction decoder to F26, M instruction decode to F10, users can according to the request of change knife action write macro program and PLC program.T directive specifies the tool, completing the library choose tool, tool library rotation direction judgment and determination of rotating interval;M directive specifies the macro program, according to the requirements in tool complete spindle back to zero, the Z axis point back to change the tool, the tool arm rotating direction, location and tool cup up and down movement.
3.1 The choice of cutter (T)
Cutting tool choice is tool library specified on the tool to change the cutter location, the action by the T instruction function.Automatic tool changer (ATC) system based on information from the position of the tool storage and T instruction, according to the given command and control system decide the knife library direction of rotation, the requirements of the steps, etc., generally, the memory can be used to model random control and mechanical control in two ways.Corresponding to their respective mechanical random control every tool set, usually between the spindle and the tool storage, to provide tool change "middle tool set".Memory model, by contrast, stochastic control using a pointer, pointer points out that the position of tool library rotation, each knives and tool set is not always one-to-one correspondence, the control mode change quickly and reliable.In according to the mechanical structure of the tool storage choices in tool control mode, the following system of pointer to a float switch tool way: by the user T directive specifies a tool, after decoding system, found in the floating of the pointer to the memory number corresponding to the cutting tool, the system use special instruction ROTB direction of rotation and rotation distance judgment the knife, tool library rotation to the target location choice tool finish tool, M6 instructions completed action in the tool, the specific process as shown in figure 3.

Fig.3.Flow chart of choosing tools
3.2 Transfer instructions (M)
Auxiliary M instruction decoding through the system to the PLC "rumet" point (internal relay), users write PLC program according to the action requirement.ATC auxiliary M instructions include M6 in knife, M19 spindle positioning, initialization M86 tool library, etc.Machining center library change knife process as shown in figure 4.

Fig.4.In flow chart
ServoWorks CNC can according to the needs of users customize the G/M/S/T macro call simplify nc programming, commonly used machine tool movement program can be integrated into a command, such as using M06 complete the change movement.The macro program can call with the same auxiliary M instructions.Within the system to specify instructions stored mobile storage unit classification, such as G00, G01, G02G03 instructions stored in the system variables such as # 4001.Macro calls the method is as follows:
O9001
G40G80
#510=#4001
#511=#4001
#512=#4003
#513=#1032AND256
#514=#BIN[#513]
（IF[#512EQ#514]GOTO N 1000）
G90G30Z0
M19
M6
G#510G#511
N1000M99

4. The PLC program development
Automatic tool change the PLC program mainly includes the library choose tool and sword arm in application.ServoWorksPLC program addresses are: machine tools to the PLC input signal (X), PLC to the input signal (Y) machine tools, CNC engine signal to the PLC engine (F), PLC engine to the CNC engine signal (G), intermediate relay (R), counter (C), the timer (T), etc.The following "rumet" point description tool change by PLC.
4.1 Library choose knife PLC program
LadderWorksPLC based automatic tool change order (as shown in figure 3) are: tools, search instructions DSCH, rotating direction and distance calculation ROTB CTR, library rotating tool count instructions.
DEX - A402 tool library tooling capacity for 24, dao library to choose the main PLC program as shown in figure 5.Program R270 storage target tool, DSCH instruction in D20 of 25 the address of the storage unit to find the same as the R270 content, and stored in the R280;CO specifies the tooling capacity, tool library ROTB instruction real-time computing target tool R290 and current tool cup, cup on C2, the step distance and direction between the R283 from storage cloth, R203.6 storage direction of rotation;C2 count done by CRT instruction, knife library rotation direction R960.3 decided to C2 counts increase and decrease, R200.4 for signals of count.
4.2 The knife arm in PLC program
In the rotation of the PLC program to realize tool arm motion control.Automatic tool change through the motor drive the CAM arm movement control the knife, knife arm with wheel braking signals and the CAM signal wheel brake signal, pine nipped dao signals, the origin, through the above signal sequence diagram write brake position.Position 1 corresponds to the origin position, position 2 corresponding tool arm forward 60 degrees, position 3 corresponding knife arm is turned 180 degrees.This research according to the flow chart of tool change written in tool PLC program, as shown in figure 6.

Fig.5.Library choose tool application Fig6.In PLC program
4.3 Storage unit number swaps
Automatic tool changer is a random continuous process, the tool change after the completion of the need to modify the content in the storage unit, ensure accurate tool change next time.Storage unit tool, swaps, complete the spindle cutter number D20 and present corresponding tool, tool cup on D + C2 (20) exchange, through the intermediate storage D18 transition, specific implementation way as shown in figure 7.

Fig.7.Access unit knife swaps
XMOV instructions to complete the storage unit data read, write, read operation on RW = 0, RW = 1 to perform write operations.
5. Test
Ladder Works console is a collection of PLC program creating, editing, compilation, operation monitoring and debugging of PLC control platform.Ladder Works PLC all sorts of function instruction is complete, the programming method is simple, support "TXT format text files.These programs are written in accordance with the requirements for Ladder Works PLC programming corresponding statements table, save to "TXT" in the document, compiled by the Ladder Works console and complete the PLC programming.As a tool of built-in PLC system software type, machine tool distribution Ladder Works PLC software needs specially configured when external I/O communication module to achieve PLC communicate with outside of the actuator.This design USES the BECKHOFF company EL1004 as a signal input module, EL2889 as a signal input module.
Finally this study will design the automatic tool change the PLC program and the macro program application in YY - 1060 machining center, verify the accuracy and reliability of the program.Open system, in manual programming model (MDI) under the dispatch 1 tool to tool change position, initialization of tool library, then select use T command specified within the scope of the cutting tool.Verified the system automatically calculates the shortest tool library rotating path method as shown in table 1.
Table 1 Knife library rotating path is calculated

When the specified target tool, beyond the cutting tool, the system error.After many debugging, complete the closest cutter replacement (library rotating a tool) need 4 s, the farthest distance in tool (library rotating 12 knife) need 6 s.Experimental results show that the designed system in our study randomly choose tool accurate tool change process, no disorderly knife phenomenon, tool change motion stability, can well satisfy the processing center automatic tool changer of quickness, accuracy and stability requirements.
6. Conclusion
Compared with the traditional automatic tool change control system, based on the technology of ServoWorks LadderWorksPLC built-in software type, with automatic tool change dedicated control instruction, greatly simplifies the programming of nc machining center tool change system and maintenance difficulty.At the same time, the technology and CNC technology can quickly and accurately finish the tool change process.With the development of pure software CNC technology, the control method will be widely used.

References
[1] ZhanShu Liu. Machining center structure, maintenance and debugging [M]. Beijing: China Machine Press, 2003.
[2] ChangJi Deng, GuanLian Jiang. Based on the PLC automatically choose knife knife application and development [J]. Journal of combination machine tools and automatic processing technology, 2010 (6) : 53-56.
[3] GU jian,NIU Yun-yan. Research on the Structure and PLC Control of a New Automatic Tool Changer[ C ]//2011 International Conference on Consumer Electronics, Communications and Networks.United States;IEEE Computer Society, 2011; 686-689.
[4] ZHANG Lian-zhong, WANG LI. Machining Center Automatic ATC Analysis and Researh [ C ]//3rd International Conference on Industrial Engineering. United States; IEEE Computer Society, 2010; 355-358.
[5] Mitsubishi. CNC EZMotion-NC E60 PLC programming Manual[ Z ]. Mitsubishi, 2002.
[6] Yin Li. Pure software of open numerical control system research and reference on the machining center [D]. Xiamen: xiamen university school of physical and mechanical and electrical, 2009.
[7] DENG Chang-qi, LI Bin. The Application and Development of Automatic Tool Selection in Tool Magazine based on PLC [ C ]//2010 International Conference on Manufacturing Engineering and Automation, ICMEA2010.Germany: Trans Tech Publications, 2010: 1959-1962.
[8] Sofe Servo System INC. ServoWorks CNC LadderWorksPLC User’s Manual[ Z ]. Soft Servo System Inc, 2006.

井冈山大学外文翻译用纸
机械，2011，12（04）
数控加工中心自动换刀系统的研究
郑新武，章明众，李春木，李寅，陈永明
（厦门大学 机电工程系，福建厦门 361005）
摘要：自动换刀系统（ATC）包括刀库机构、换刀机构以及控制系统3个部分，是加工中心的重要组件之一。为了解决数控加工中心自动换刀速度慢、稳定性低及控制系统编程复杂等问题，将一种软件式内置PLC技术应用于自动换刀系统中。在分析自动换刀系统的基本结构、工作原理以及研究圆盘刀臂式自动换刀系统的控制流程的基础上，结合ServoWorksCNC技术，开发了适用于各种自动换刀机构的PLC程序以及宏程序。最后，将所开发的控制系统应用于YY-1060立式加工中心，其在4s-6s内可完成整个换刀过程。研究结果表明，换刀过程快捷、准确、可靠，完全能够满足使用的要求。
关键词：加工中心；自动换刀；可编程逻辑控制器

1.引言
利用刀库(MAG)实现自动换刀是目前加工中心大量使用的换刀方式,独立的刀库大大增加了刀具的存储数量,有利于扩大机床的功能,并能较好地隔离各种影响加工精度因素的干扰。加工中心的常用刀库类型有：盘式刀库和链式刀库。刀库换刀方式按照换刀过程有无机械手参与，分成有机械手换刀和无机械手换刀。本研究以YY-1060立式加工中心装备的DEX-A402盘式刀库有机械手自动换刀机构为对象，对自动换刀系统(ATC)进行研究。
可编程控制器（PLC）是自动换刀系统的核心部分。目前，国内对自动换刀机构的控制多采用传统PLC（简称硬PLC）及单片机，如三菱FX系列的PLC控制、西门子S7-200系列PLC、AT98C51单片机。硬PLC控制方法没有专用的选刀指令，需要编写复杂的选刀PLC程序，同时无法通过宏程序简化数控编程过程；采单片机控制电路搭建复杂，系统稳定性较低，编程复杂。本研究采用的LadderWorks是一种基于ServoWorks技术的软件式内置PLC系统，可与CNC之间进行内部的信号的快速传输。

2.库的结构及换刀动作
自动换刀机构主要构成包括：刀臂电机、凸轮、刀臂、刀库电机、刀杯、刹车、松夹刀、原点讯号轮等。DEX-A402自动换刀机构如图1所示。

图1 自动换刀机构 图2 刀臂动作
刀臂动作由步进电机驱动，换刀动作分4各步骤完成。刀