Research On Gear Modification By Means Of Pulse Electrochemical Machining Based On Singlechip Control

The quality of gear, which is used widely as a basic product, directly influences the quality of relative electromechanical products of our country and their competition in the international market. On the whole, there are big differences comparing our country's gears with foreign gear products on such technological standards as load capacity, service life and noise level etc. What's more, the focal point to improve gear properties is still the form of gear tooth. Gear modification is the critical technology to improve gear transmission, raise its service life and motion precision. Therefore, to develop researches on gear modification is practically significant.Scholars at home and abroad have been developing many researches on theories and machining technologies of gear modification. Theories of gear modification have been mature by now. In this paper, attempts to apply pulse electrochemical machining technology (PECM) to gear modification machining were carried out after studying the methods of gear modification machining nowadays at home and abroad and researches on PECM technology and its applications that Nontraditional Machining Institute of Dalian University of Technology has been engaged in recently. A series of researches have been developed on cathode design, process control and machining gap control etc. Several results that are valuable to applications and instructively significant have been gained.PECM is a new technology that the pulse power, especially the high frequency and short pulse current power, is applied and the traditional direct current power is replaced instead. Compared with traditional electrochemical machining, the characteristics of electrochemistry, flowing field and anode dissolution of this new technology are improved and its machining precision, surface quality and machining efficiency are enhanced greatly. In this paper, through researches on the theory of PECM, the PECM technology is applied to gear modification machining and a series of instructive rules during machining process are studied. Gap, flowing field and current density are three important factors that influence the machining precision and surface quality of PECM. In this paper, the research emphasizes on cathode tool design and process control. Because the tiny and steady machining gap is allowed in PECM, new ideas and methods that differ from traditional electromechanical gear modification can be used to design the cathode of PECM gear modification. So this paper develops several schemes of cathode design and their merits and demerits are analyzed and compared. The author also develops the simulation software of gear modification machining, through which the machining process can be simulated and the design of cathode can be aimed so that the cathode design can be optimized, the experimental expense can be reduced and the developing cycle time can be shortened.In this paper, aimed at the character of gear modification, the control system of PECM gear modification has been designed based on singlechip to realize the automation of the machining process. The system consists of stepper motor control module, human-computer interaction module and communication module between singlechip and PC. It has strong ability in anti-jamming and good flexibility and can satisfy the experimental demand. What's more, human-computer interaction can be convenient and easy through the communication with PC.According to Faraday Law, the eroded quantity of metal depends on current density and machining time. So deciding the pulse current magnitude and real-time controlling the machining time of each point on the gear tooth surface according to the demand and rule of machining are important contents of PECM gear modification research. In this paper, combined with lab conditions and based on the thought that ensuring the modification quantity of gear and improving machining efficiency, experiments of gear modification bymeans of PECM using two schemes of cathode design are carried out. The experimental results are analyzed t...