Research On NC Machining Method Of Complex Curved Surface Based On The Principle Of Contact

It is very hard for traditional three-dimensional machine tool to NC machining complex curved surface with high precision,because both ball head milling cutter and conical milling cutter will produce too much cutting allowance.As the threedimensional machine tool cannot make the location point and tool moving at the same time,but this problem could be solved in the five coordinate of machine tool.In the five coordinate machine tool,while it is possible to adopt such as residual height method is applicable to all kinds of curved surface,it still cannot change position of the cutting solution.By researching,we found that using the contact principle the cutting problem is resolved.The principle of contact can be explained by a life experience: you can't spoon all the soup with a spoon,but a shovel can.Because pot can be described as a machining surface,the spoon will generate more allowance,but shovels won't,this is because the shovels meet contact principle,and the shovel tangent to the pot.From the point of view of NC machining principle we can give our contact principle a definition like this: A processing method,which should make sure the normal vector of the knife site parallel with the machining cutter knife axis all the time.This paper takes ellipsoid processing for example,further study the NC machining method of complex surface based on contact principle.It also focuses on the introducing of contact principle,and a method for calculating normal vector of tool point in curved surface machining is optimized,it verifies the feasibility of the complicated surface machining method based on the principle of cutting,gives a method for the study of tool and tool path planning in the principle of cutting contact.