Research On Optimization Design Of Hoisting Mechanism Of Medium And Small Tower Cranes

Under the condition of modern production,the tower crane is regarded as a machine for vertical and horizontal transporting materials.In the aspect of large-scale construction projects,such as:the construction of high-rise buildings,the laying of railway and transportation hub,mining and metallurgy and other fields,play an indispensable role.However,due to the domestic technical reasons,the total weight and energy consumption of the domestic crane is huge,resulting in significant increase in production costs and operating costs.In response to the national requirements for the lightweight design of the crane,the tower crane must be speeded up the pace of product replacement.In this thesis,the lifting mechanism of one of the main components of the small and medium sized tower crane was studied,the layout scheme design of the main components was carried out,and for the small and medium-sized crane hoisting mechanism for optimized design,to achieve the purpose of reducing the size and weight of the lifting mechanism and reducing the amount of material used in the product.Firstly,the thesis studied the spatial layout of the components of the lifting mechanism,the middle and small type lifting tower crane hoisting mechanism layout design model was put forward,a variety of solving layout was completed by isomorphism and mutual interference elimination scheme,and adopted the analytic hierarchy process to carry on the qualitative analysis and the quantitative analysis to the layout scheme,the best space layout scheme of meet the engineering requirements was obtained,to lay the foundation for the lifting mechanism optimal solution.Secondly,according to the characteristics of layout scheme of lifting mechanism of small and medium sized tower crane and the design features of main design parameters of cylindrical gear transmission system,drum,motor and brake,the mathematical model of optimization design for the components of the reducer,the drum,the motor and the brake was established,derived its general expression,and the optimization module of MATLAB was used to solve the problem,the optimal value of the main design parameters of the lifting mechanism was obtained.Again,on the basis of the optimal solution of the main design parameters of the lifting mechanism was optimized,and on the basis of satisfying the working performance of the lifting mechanism,appropriated parameter coordination for initial optimization results,and make interference test for the coordinated parameters,the mixed discrete values of the design parameters were obtained.Finally,based on the MATLAB software platform,the design of the man-machine interactive automatic design system was developed,integrated visual design for the space layout scheme design of lifting mechanism and main parameter optimization design and parameter coordination and interference checking of initial optimization results were realized,layed the foundation for small and medium sized high tower crane lifting mechanism design.Verified by examples,the software system for automatic design of lifting mechanism of small and medium sized tower crane which had been completed,could be used to quickly complete the space layout scheme design,the main parameters for optimization design of the lifting mechanism and the work of parameter coordination and interference test,the results showed that the proposed theory and method were feasible and effective,the achievements played an effective role in shortening the cycle of product research and development,reducing the design and manufacturing cost,improving the design efficiency and the competitiveness of products in the market.