Identification And Solving Method Of Difficult Function Elements And Its Application For Tightening Knotter Design

In the new economic era,product innovation and design capabilities have become the company's core competitiveness.In the process of the product innovation design,the identification and solution of difficult function elements is the difficulty of design and key to product success.In the development of the fully automated strapping machines,due to factors such as customer demand and space constraints,it is difficult to solve the tightening knotter function.On the basis of systematic research on the method of the difficult function elements and its related theory,this paper presents a method for identifying the difficult function elements based on root cause analysis,The effect synthesis method for solving the function elements is improved,the solving method of difficult the function elements based on the trimming is proposed,and using the innovative design of the tightening knotter for the broom strapping machine as case study.The main work of the thesis is as follows:(1)Analyze the reasons for the difficulties in solving the difficult function elements and further define the difficult function elements,based on the existing research on difficult function elements.Based on root cause analysis,a method for identifying difficult function elements is proposed.Firstly,the paper analyzes the constraint type,and integrate the constraints of the function elements into the function structure as an input to establish an extended functional structure.Then,starting from the output stream with relate to problem appearance,causal reasoning on functional structure is performed to determine all root causes that generate the output steam and all constrained types of the problem function elements.Finally,the constrained relationship between the conflict area and the function elements are determined to realize the identification of the difficult function elements.(2)The problem solving method based on the effect comprehensive method is improved,and the method based on function trimming is proposed.The former is used for the direct solution of difficult function elements,with the support of the effect knowledge base,the correlation effect is searched,and the available effect range is reduced under the constraint condition.Finally,the solution is completed by combining the engineering examples in the effect knowledge base.The latter,first analyzes the feasibility of trimmingand replacing the difficult function elements directly,and then reduces the difficulty of solving the difficult function elements by trimming the constraint function elements and the constrained input stream of the difficult function elements.Finally,use the effect reasoning to complete the solution.(3)An innovation design of the broom-like tightening knotters where suitable for knot seedlings and other seedling crops tied is completed,based on above identification and solution methods of the difficult function elements,the conceptual design of the tightening knotters have been proposed,and the finite element analysis of the key parts in the tightening knotters have been carried out.