| Diamond has some excellent performance in physics, chemistry, mechanism, so it is used to science and engineering field where need diamond cutting tool with smooth surface and precise size as well as shape. As cutting tools, diamond is most ideal material, and it has been used in precise process field. How to make diamond cutting tool with sharp knife-edge, high precision and quality, it direct influence the level of ultra precise process technology and become focus of research. But diamond is rigid, wearable, friable, resist erode, so it is very hard to make ultra precise diamond cutting tool. Making diamond cutting tool has become key technology and need to research emergently. There are many methods of making cutting tool now, but mechanical lapped method is mostly used to make cutting tool, because of mature technology, process stabilization, easy control and low cost.Making ultra precise and high quality diamond cutting tool is a challenge of technology. There are some factors which influence making diamond cutting tool, like process condition, environment, equipment and operate skill. But most important and base problem is improving process condition and lapped equipment in our country, so how to improve move's precision and stabilization of lapped machine is the key problem.In this paper, the primary factors which influence move's precision and stabilization of lapped machine is discussed and analyzed. A precise, minitype, high speed spindle system has been designed, by using sensorless brushless DC spindle motors which is built with fluid dynamic bearings;The Servo feed systems based on closed loop feedback device which is made up of voice coil motor, servo head and servo disk is designed and done. In order to lap diamond in precision and stabilization, the minitype precise lapped machine includes these researches:The minitype and precise spindle system has been design and done. It adopts fluid dynamic bearings technology and sensorless BLDC motor technology so that spindle system rotates stably and precisely. Though the motor figure is simple, thecontrol system is very complicated. In order to solve this problem, IC ML4426 is adopted as core of spindle system, and the peripheral circuit has been design. PWM control is adopted to achieve current and speed closed loop control.The servo feed system is designed to achieve track control. The core of servo feed system is make up of voice coil motor, servo head, servo disk, it can make sure the system move stably and precisely. In order to achieve servo control of servo feed system, servo information detect circuit and control software is designed, and is used to pick-up servo information form servo disk. The track control software is designed by C programme.Precise lapped disk is done, it utilize high precise plane geometry disk as base disk and coat diamond-like carbon film. Precise lapped disk of this paper can improve the problem of lapped powder which is pockety and dissimilarly high.Air filter is also designed. It is used to protect lapped machine and improve lapped environment.Finial, assembled lapped machine is used to experiment of making diamond tool. Experiment include: 1. Lapped surface of diamond, the objective of this experiment is testing the lapped machine's stability by detecting quality of diamond cutting tool surface. Tests by the AFM show that the surfaces of diamond edge's Ra is 6.725nm and whole diamond average Ra is 3.25nm. The result indicated the lapped machine is precise and steady. 2. Lapped knife-edge of diamond cutting tool. The objective of this experiment is also test the lapped machine's stability by compare lapped knife-edge of diamond cutting tool by lapped machine which is design in this paper and general lapped machine. The test result indicated our lapped machine can still grind straight knife-edge when angle is less 90°. So the result also indicated the lapped machine precise and steady.
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