数控机床自动润滑系统毕业设计

江西城市职业学院2011届毕业设计

题目：数控机床自动润滑系统设计

分院：机电工程学院

班级：数控08—1班

学号： 080744080104

学生姓名： XXXX

起讫日期：

指导教师：职称：

教研室主任：

审核日期：

数控机床自动润滑系统

摘要

机床润滑系统的设计、调试和维修保养，对于提高机床加工精度、延长机床使用寿命等都有着十分重要的作用。但是在润滑系统的电气控制方面，仍存在以下问题:一是润滑系统工作状态的监控。数控机床控制系统中一般仅设邮箱釉面监控，以防供油不足，而对润滑系统易出现的漏油、油路堵塞等现象，不能及时做出反应。二是设置的润滑循环和给油时间单一，容易造成浪费。数控机床在不同的工作状态下，需要的润滑剂量是不一样的，如在机床暂停阶段就比加工阶段所需要的润滑油量要少。针对上述情况，在数控机床电气控制系统中，对润滑控制部分进行了改进设计，时刻监控润滑系统的工作状况，以保证机床机械部件得到良好的润滑，并且还可以根据机床的工作状态，自动调整供油、循环时间，以节约润滑油。

数控机床中润滑系统为间歇供油工作方式。因此，润滑系统中的压力采用定期检查方式，即在润滑泵每次工作以后检查。如果出现故障，如漏油、油泵失效、油路堵塞，润滑系统内的压力就会突然下降或升高，此时应立即强制机床停止运行，进行检查，以免事态扩大。油面过低以往习惯的处理方法是将“油面过低”信号与“压力异常”报警信号归为一类，作为紧急停止信号。一旦PMC系统接收到上述信号，机床立即进入紧急停止状态，同时让伺服系统断电。但是，与润滑系统因油路堵塞或漏油现象而造成“压力异常”的情况不同，如果润滑泵油箱内油不够，短时间不至于影响机床的性能，无需立即使机床停止工作。但是，出现此现象后，控制系统应及时显示相应的信息，提醒操作人员及时添加润滑油。如果操作人员没有在规定时间内予以补充，系统就会控制机床立即进入暂停状态。只有及时补给润滑油后，才允许操作人员运行机床，继续中断的工作。针对“油面过低”信号，这样的处理方法可以避免发生不必要的停机，减少辅助加工时间，特别是在加工大型模具的时候。在设计时，我们将“油面过低”信号归为电气控制系统“进给暂停”类信号，采用“提醒——警告——暂停，禁止自动运行”的报警。一旦油箱内油过少，不仅在操作面板上有红色指示灯提示，在屏幕上也同时显示警告信息，提醒操作人员。如果该信号在规定的时间内没有消失，则让机床迅速进入进给暂停状态，此时暂停机床进行任何自动操作。操作人员往油箱内添加足够的润滑油后，只需要按“循环启动”按钮，就可以解除此状态，让机床继续暂停前的加工操作。

该系统采用PLC进行控制。正常情况下，按下启动按钮，润滑电动机M立即运行，20S

后此时油压检测开关应该由断开变为闭合，之后润滑电动机立即停止运行。当主轴电机运行时间累积达到30分钟时，管路油压要下降到使压力检测开关复位，这时润滑电动机要立即运行20S，开始增压，此后周而复始的运行。当润滑系统发生管路泄露、堵塞、润滑电动机过载时，润滑电动机都要停止运行，并发出报警，报警的形式为发光二极管以0.6秒的间隔闪烁并驱动警铃报警，直到人工按复位按钮后报警才消失。当油箱中润滑油不足时，由低液位检测开关对液面高度进行检测，这时主轴和润滑电动机都要停止，同时发光二极管一直常亮。同时启动补给油箱对当前油箱进行加油，当液面到达高液位检测开关时停止补给。

关键词：数控机床润滑系统 PLC 故障分析

ABSTRACT

Lubrication system design and machine commissioning and maintenance, to improve the machining precision machine tools, prolong service life and so on, all have very important role. But in the lubricating system of electrical control, still exist in the following problems: one is the lubrication system working condition monitoring. CNC machine control system in general only a mailbox glaze monitoring, in case oil-supplied insufficient, and for lubrication system easy appear oil, fuel blockage phenomenon, cannot make timely response. 2 it is setting of lubrication oil of circulation and give time onefold, easy to cause the waste. Nc machine tools in different work condition, need lubricating dose is different, such as in the machine tool suspended stage than processing stage need lubricating oil amount to little. In view of the above situation, on the nc machine, electric control system for lubrication control parts were improved design, the time monitoring lubrication system, to ensure the working conditions of the machine mechanical parts get good lubrication, and still can according to machine work condition and automatic adjustment oil-supplied, cycle time, so as to save the lubricating oil.

Nc machine tools in lubricating system of the intermittent oil-supplied way to work. Therefore, in the lubricating system pressure by regular examination way, namely the lubrication pump every time after work inspection. If the malfunction, such as oil, oil pump failure, fuel blockage, lubrication system of pressure will suddenly slumps or rise, at this time, should now mandatory machine stop running, inspect, lest things expand. Oil noodles too low past habits of the processing method is will "oil noodles too low" signal and "abnormal pressure" alarming signals into categories, as an emergency stop signals. Once PMC system to receive the signal, the machine immediately enter the emergency stop state, while allowing servo system power outages. But, because oil and lubrication system caused by blocked or leakage "abnormal pressure" situation is different, if lubrication pump oil tank inside short time unapt influence is insufficient, the performance of the machine tool, without immediate machine stop working. But, appear this phenomenon, control system should be timely shows the corresponding information, remind operation personnel to add lubricating oil. If the operator does not within the time specified, compensatory system will be controlled machine tool entered immediately suspend state. Only after timely supply lubricating oil will allow

operators operating machine, continue to interrupt. In view of "oil noodles too low" signal, the treatments can avoid unnecessary downtime, reduce auxiliary processing time, especially in the processing of large mould. In the design, we will "oil noodles too low" signals into electric control system "feeding pause" kinds of signal, adopting "remind - warning - timeout, prohibit automatic operation" of alarm. Once inside the tank oil too little, not only in the operation panel have red indicator light hint, on the screen also shows the warning message, remind the operating personnel. If the signal within the prescribed time not disappear, then let machine quickly went into feed suspended state, when suspended machine tool any automatic operation. Operators to tank inside add enough oil, only need to press the "start" button, circulation can terminate the state, let the machine continue to pause before processing operation.

This system USES PLC control. Under normal circumstances, press the start button, lubrication motor M immediately after operation, at hydraulic testing switch 20S by disconnect into closed, should stop immediately after lubrication motor running. When spindle motor running time cumulation reach 30 minutes, hydraulic pipeline to descend to make pressure detecting switch resets when lubrication motor must immediately 20S, start running, thereafter the cycle of operation pressurization. When the lubrication system occurred pipeline leak, jam, lubrication motor, lubrication motor overload will stop running and alarm and alarm in the form of leds to 0.6 seconds of interval and drive the alarm flashing alarm, press the reset button until artificially after alarm before it disappeared. When the tank lubricant in shortage, from low level detection switch to liquid surface height testing, when spindle and lubrication motors will stop, and leds have been ChangLiang. And the launch of current supply tank tank bunkering, when the liquid surface high level detection arrive when you stop supply switch.

Key words：CNC machine Lubrication system PLC Failure analysis

目录

一、绪论 (1)

二、润滑系统的分类及其要求 (2)

2.1 润滑系统和方法的分类 (2)

2.1.1分散性润滑系统 (2)

2.2.2集中性润滑系统 (2)

2.2润滑系统的选择原则 (3)

2.3润滑系统的基本要求 (4)

三、润滑系统的控制原理 (4)

3.1 电气控制原理 (4)

3.2 自动控制原理 (6)

四、数控机床润滑系统的 PLC控制 (7)

4.1可编程控制器PLC结构及其功能 (7)

4.1.1 PLC的简介 (7)

4.1.2 PLC的硬件结构及其外部信息的转换 (7)

4.1.3 数控机床PLC的功能 (7)

4.2润滑系统PLC的梯形图 (8)

4.3 PLC的特点 (10)

五、润滑系统的工作监控及其故障分析 (11)

5.1润滑系统工作状态的监控 (11)

5.2润滑时间及润滑次数的监控 (11)

5.3润滑报警信号的处理 (11)

5.4润滑系统的故障分析 (12)

六、结语 (13)

七、参考文献 (13)

八、谢辞 (13)

九、注释 (14)