The Study On The Wire Feeder Of Arc Spray Systems

The wire feeder is one of the most important parts in an arc spray system. The stability of a wire feeder is the key factor, which has determined the high quality of coatings. The performance of a wire feeder system is related to many factors. Therefore, a study of the resistance of a wire-feeder is the basis of drive modes, drive power and control strategies. First, the thesis studied the variety roles of the wire-feeder resistance. And then the model of calculation resistance was developed and was verified by testing experiment. At last, it has proposed some measures to improve the performance of wire feeder systems and has provided the related calculation model.The thesis is based on dynamics and tribology theory. This investigation studies a wire feeder of a company's arc spray equipment. The thesis studies on the resistance of a wire feeder system from the theory. According to the principle of resistance brought about, the factors, which caused the resistance was analyzed with energy method and their models were developed. The mainly results are in the following: Firstly, it has discussed the factors, which influenced the speed fluctuation in wire feeder system. Secondly, the wire-feeder resistance was analyzed and calculated. It has shown that the curvature of a wire tube was the most primary factor, which caused the resistance fluctuation. Thirdly, the scope of speed fluctuation was analyzed and calculated. It has proposed that the resistance was the main factor, which caused the speed fluctuation. Fourthly, it has deduced the transfer function and dominant resonant frequency of transmission mechanism.With the experiment equipment of mechanical system efficiency, we have respectively tested the wire feeder with working load and without load. The results of experiment are as follows: Firstly, the curvature of the wire tube was the main factor, which affected the speed fluctuation. The resistance increased with the curl degree of a wire tube. Secondly, the resistance was different when the material of wires was different. The bigger the fiction coefficient is, the bigger resistance is. And the resistance fluctuation is more obvious when higher stiff material wire is used. Thirdly, if the wires of different material were feeding at the same speed, the consumed power was different. If the same wires were fed at different speed, the consumed power would be different, too. Fourthly, the transmission efficiency of wire feeder system is lower. It is about 73.3 percent. Fifthly, in order to ensure the uniformity and stability of speed, the system stiffness must be increased.On the base of wire-feeder resistance from theory to experiment, it has proposed some measures to improve the performance of a wire feeder system, such as improving the transmission efficiency of worm and gear, improving the stiffness of mechanical drive link, selecting solid characteristic motor, installing flywheel on the high shaft and adopting loop locked control to the wire feeder speed. The studies have provided a more detailed full-scale principle of configuration for calculating motor power, selecting motor and the speed control strategy. This paper has still provided more convenience procedures and examples for scientific research people in the field.