摘要
随着我国国民经济迅速发展和国防建设的需要，对高档的数控机床提出了急迫的大量需求。机床是一个国家制造业水平的象征。而代表机床制造业最高境界的是五轴联动数控机床系统，从某种意义上说，反映了一个国家的工业发展水平状况。
长期以来，以美国为首的西方工业发达国家，一直把五轴联动数控机床系统作为重要的战略物资，实行出口许可证制度。特别是冷战时期，对中国、前苏联等社会主义阵营实行封锁禁运。爱好军事的朋友可能知道著名的“东芝事件”：上世纪末，日本东芝公司卖给前苏联几台五轴联动的数控铣床，结果让前苏联用于制造潜艇的推进螺旋桨，上了几个档次，使美国间谍船的声纳监听不到潜艇的声音了，所以美国以东芝公司违反了战略物资禁运政策，要惩处东芝公司。所谓面接触式加工是指以面接触成型的加工方式，如端面铣削(磨削)加工．这种加工方式的主要特点是：由于切削点有较高的切削速度，周期进给量大，因而它具有较高的加工效率和精度．但由于受成型方式和刀具形状的影响，它主要适合于中凸曲率变化较平坦的曲面的加工．五坐标联动数控加工当前和今后研究的重点
所谓线接触式加工是指加工过程中以线接触成型的加工方式，如圆柱周铣、圆锥周铣、樟形窿削及砂带磨削等．这种加工方式的特点是：由于切削点处切削速度较高，因而可获得较高的加工精度，同时，由于是线接触成型，因而具有较高的加工效率，已发展到对任意曲面线接触加工的研究。
五轴联动机床的使用，让工件的装夹变得容易。加工时无需特殊夹具，降低了夹具的成本，避免了多次装夹，提高模具加工精度。采用五轴技术加工模具可以减少夹具的使用数量。另外，由于五轴联动机床可在加工中省去许多特殊刀具，所以降低了刀具成本。五轴联动机床在加工中能增加刀具的有效切削刃长度，减小切削力，提高刀具使用寿命，降低成本。
采用五轴联动机床加工模具可以很快的完成模具加工，交货快，更好的保证模具的加工质量，使模具加工变得更加容易，并且使模具修改变得容易。在传统的模具加工中，一般用立式加工中心来完成工件的铣削加工。随着模具制造技术的不断发展，立式加工中心本身的一些弱点表现得越来越明显。现代模具加工普遍使用球头铣刀来加工，球头铣刀在模具加工中带来好处非常明显，但是如果用立式加工中心的话，其底面的线速度为零，这样底面的光洁度就很差，如果使用四、五轴联动机床加工技术加工模具，可以克服上述不足。
关键词：五轴加工中心机，驱动，控制
Abstract
Carved from the processing principle of speaking is a kind of drilling and milling, engraving machine data input mode according to the needs of ease. Computer engraving machine with laser engraving and mechanical engraving of the two categories, these two categories have a large power and small power of the points. Because the engraving machine is very wide range of applications, it is necessary to understand the most suitable range of engraving machine application. Small power only suitable for double color plate, building model, small signs, three-dimensional crafts. Because the power is too small and greatly affect the scope of its application. Large power engraving machine engraving machine power can do little things. The most suitable for large-scale cutting, relief, sculpture. In the numerical control machine tool, the electric spindle usually uses the frequency conversion speed regulation method. There are three kinds of control modes, which are ordinary frequency conversion drive and control, vector control drive, control and direct torque control.
The ordinary frequency conversion is the scalar drive and the control, its drive control characteristic is the constant torque drive, the output power and the rotational speed is proportional. The dynamic performance of the common variable frequency control is not good enough, the control performance is poor at low speed, the output power is not stable enough, also does not have the C axis function. But the price is cheap, the structure is simple, generally used for grinding machine and ordinary high speed milling machine, etc..
Vector control technology to imitate the DC motor control, rotor field oriented, with the vector transform method to achieve the drive and control, with good dynamic performance. Vector control drive at the beginning of a great torque value, coupled with the simple structure of the electric spindle itself, the inertia is very small, so the acceleration is large, can be achieved immediately after the start to allow limit speed. The drive and open loop and closed loop two. The latter can be achieved with position and velocity feedback, not only has a better dynamic performance, also can realize the C shaft power; and the dynamic performance of the former is a bit poor, also do not have c axis function, but the price is relatively cheap.
Key words: engraving machine, drive, control
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