Classified according to the control trajectory of CNC milling machine motion

The point-position control of the CNC milling machine only requires the accurate positioning of the moving parts of the machine tool from ~ point to another point. The requirements for the movement trajectory between points are not strict, and rf1 is not added during the movement process. , The movement of each coordinate axis

Is irrelevant. In order to achieve both fast and accurate positioning in precision CNC machining, the displacement between two points generally moves quickly, and then slowly approaches the positioning point to ensure positioning accuracy.
The point position of CNC milling machine is _D track control drilling machine, CNC boring machine, CNC punching machine, etc. With the development of numerical control technology and the reduction of the price of numerical control systems, numerical control systems used solely for point control have become rare.

Linear control CNC milling machine Linear control CNC milling machine is also called parallel control CNC milling machine. Its characteristic is that in addition to controlling the accurate positioning between points, it also controls the moving speed and route (trajectory) between two related points. The movement route only moves parallel to the machine coordinate axis, that is to say, there is only one coordinate axis controlled at the same time (that is, there is no need for interpolation operation function in the CNC system). During the shifting process, the tool can cut at the specified feed rate. Generally, only rectangular and step-shaped parts can be processed.

Precision CNC machining CNC milling machines with linear control functions mainly include relatively simple CNC lathes, CNC milling machines, CNC grinders, etc. The numerical control system of this kind of machine tool is also called the linear control numerical control system. Similarly, Jing-controlled machine tools used solely for linear control are rare.

Contour control CNC milling machine

Contour control CNC machine tools are also called continuous control CNC milling machines. Its control feature is that it can simultaneously control the displacement and speed of two or more motion coordinates. In order to meet the requirements of the relative motion trajectory of the tool along the contour of the workpiece to meet the requirements of the machining contour of the workpiece, the displacement control and speed control of each coordinate movement must be accurately coordinated in accordance with the prescribed proportional relationship.

Therefore, in this type of control method, precision CNC machining requires the numerical control device to have interpolation functions. The so-called interpolation is the basic data input according to the program (such as the end point coordinates of the straight line, the end point coordinates of the arc, and the center coordinates or radius). , Through the mathematical processing of the interpolation calculator in the numerical control system, the shape of the straight line or arc is described, that is, while calculating, the pulse is distributed to each axis controller according to the calculation result, so as to control the linkage displacement of each coordinate axis The amount conforms to the required profile.

During the movement of the CNC milling machine, the tool continuously cuts the surface of the workpiece, and can process various straight lines, arcs, and curves.