Design And Optimization Of Automatic Welding Device For Automobile Heat Exchangers

The automobile heat exchanger is an important part of the automobile air conditioning system.Currently,manual welding is still the main way of heat exchanger welding,there are many disadvantages in this manual operation,such as low efficiency,poor welding quality,harsh working condition.Therefore,research of a suitable automatic device has important significance for the heat exchanger welding.Based on the welding process,an overall design of automatic device for the heat exchanger welding is developed according to the requirements.Then the optimization design for structure and precision of the device are completed.The main contents are as follows:(1)The requirements for automatic welding are analyzed,and a functional principle model is established based on the analysis of heat exchanger process.With comparative analysis of each functional principle model,a program of the automatic welding system is developed,including the overall structure scheme,the automatic welding motion program and the seam tracking program.(2)The detailed structure of automatic welding equipment is designed.Referring to the requirements of uniform welding,the speed and force characteristics of moving robot are analyzed.(3)The static characteristics of the automatic welding equipment are simulated according to different positions of mobile robot in the circular track.Mathematical model for structural parameters of optimization design is established with the minimum weight and deformation of device set to be design object.After optimization with multi-island genetic algorithm(MIGA),desired result is obtained.(4)At first,a static error model is established with the multi-body system theory after the analysis of error sources.Based on analysis of error sensitivity,minimization of the manufacturing cost is taken as target to optimize and distribute the error parameters with MIGA.Finally,the precision of the overall device is optimized based on the global optimization method after a comprehensive analysis of the relationship between static deformation error and dynamic deformation error.