The CAD System Development Of The Grinding Wheel Cross-sectional Profile Machining The Micro-diameter Drill's Flute

Because of the rapid development of the modern precise manufacturing and micro- electronic manufacturing in the latest twenty years, consequently, higher requirements have been putted forward to the manufacture technology of the micro-diameter drill bit.Twist drill flute is an important part of the drill bit. Through the comparison of the five means which can machine the twist drill flute,we have gotten that the highest precise method is grinding.During the course of grinding the drill flute, the main determinants of the flute's precision are the grinding wheel cross-sectional profile's precision and the relative position precision between the grinding wheel and the drill. The purpose of the paper is seeking the grinding wheel's cross-sectional profile, which can machine the highest precise flute of the micro- diameter drill bit and also test the correctness of the solving course, on the condition of the known end-sectional curve of the drill bit and the relative position parameters between the grinding wheel and drill bit.First of all ,on the basis of the predecessors' theory analysis, the paper concludes that the micro-diameter drill flute end-sectional curve can be replaced by arc (certainly, end- sectional curve can probably be other shapes ).Based on these, the paper solves the grinding wheel cross-sectional profile of machining this micro-diameter drill flute by applying mathematics theory knowledge (the method to solving the grinding wheel cross-sectional shape is also fit for any shape of drill end-sectional curve). During the course of solving the grinding wheel cross-sectional profile, it also analyses the grinding wheel cross- sectional profile errors and the errors' sensitive parameters,which are resulted by the existence of the drill end-sectional errors and the relative position errors between the drill bit and the grinding wheel.At the same time ,it analyses the possible interference phenomenon that can be occurred in the course of machining drill bit flute by the grinding wheel cross-sectional profile solved. At last, according to the course of solving the grinding wheel cross-sectional profile and relative mathematic knowledge,the paper develops the CAD system based on the WINDOWS platform. The CAD system can solve the grinding wheel cross-sectional profile of machining drill bit flute. Applying the system, after inputting drill bit's relative parameters and the relative position parameters between the drill bit and the grinding wheel, the grinding wheel cross-sectional profile we need can be obtained.