Main body description of high speed CNC system

NC machining process is completed in a NC machining process system composed of NC machine tool, cutting tool, fixture and workpiece. CNC plus program controls the movement path of cutting tool relative to workpiece. Therefore, the unity of CNC machine tools, fixtures, tools and workpieces is called CNC machining process system.

numerical control machine. The machine tool that adopts numerical control technology or is equipped with numerical control system is called numerical control machine tool. Numerical control machine tool is a kind of machine integration processing equipment with relatively high technology intensity and automation degree. It is the main body of numerical control processing and the working machinery of parts processing.

High speed CNC fixture. In mechanical manufacturing, the device used to clamp the workpiece and guide the tool is called fixture. In the process of mechanical manufacturing, fixture is widely used, from blank manufacturing to product assembly and testing of each production link, there are many kinds of fixture. The fixture is used to fix the workpiece and keep the correct position, which is the link to realize the data processing.

Tool. Metal cutting tool is an important tool in modern machining, whether it is ordinary machine tool or CNC machine tool, must rely on the tool to complete the cutting work. Tool is the bridge to realize NC machining.

Main elements of high speed CNC programming technology

1. According to the principle of giving full play to the function of CNC machine tool, the reasonable machining method and process route are determined.
2. When designing and selecting NC machining tools, the factors such as machining methods, cutting parameters and workpiece materials should be considered to meet the requirements of convenient adjustment, good rigidity, high precision and good durability. When designing and selecting NC machining fixture, it should be able to quickly complete the positioning and clamping process of the workpiece, so as to reduce the auxiliary time. And try to use modular fixture to shorten the production preparation cycle. In addition, the fixture used should be easy to install on the machine tool to coordinate the dimensional relationship between the workpiece and the machine coordinate system.
3. The selection of high-speed CNC tool setting point is the starting point of program execution. The selection should be based on the principles of simplifying programming, easy alignment, easy inspection in machining process and reducing CNC machining error. The tool setting point can be set on the workpiece to be processed, or on the fixture or machine tool. In order to improve the machining accuracy of parts, the tool setting point should be set on the design basis or process basis of parts as far as possible.
4. In order to improve the utilization rate of the machine tool, the pre adjustment outside the machine tool should be used as far as possible, and the pre adjustment size should be input into the CNC system in time before running the program, so as to realize the tool compensation.
5. CNC machining route is determined to ensure the accuracy and surface roughness requirements of the machined parts; shorten the tool path as far as possible, reduce the empty tool travel; it is conducive to simplify the numerical calculation, reduce the number of program segments and programming workload. The process route is formulated to process the parts on the machining center. Due to the many processes of parts processing and the variety of tools used, rough machining, semi finish machining and finish machining have to be completed even under one-time clamping.
6. The cutting parameters include cutting depth, spindle speed and feed speed. The specific value of cutting parameters should be comprehensively considered according to the provisions of the manual of CNC machine tool, the material of the workpiece to be processed, the processing content and other high-speed CNC process requirements, and combined with the experience data.

The quality of NC process design will directly affect the size accuracy and surface quality of NC machining, the length of processing time, the consumption of materials and labor, and even directly affect the safety of processing. Using large computer gong to process CNC machine parts, the general process from parts drawing to qualified products is as follows:

1. According to the shape and size of the workpiece, material and technical requirements specified in the part drawing, the large-scale computer gong processing carries out the design and calculation of the process program (including the processing sequence, the relative movement path of the cutter and the workpiece, the stroke and the feed speed, etc.).
2. Then, according to the form of “numerical control device identification code”, it can be programmed.
3. The control medium (such as perforated paper tape) is made according to the number code, text code and symbol number on the part processing program sheet.
4. Through the photoelectric reader, the perforated paper tape converts the optical signal with or without holes into electrical signal and inputs it to the numerical control device.