Mechanization Analysis And Experimentation Research Of Walnut Shearing-extrusion Flexible Shell-crushing

In order to improve the income level of farmers, accelerate the development of the rural economy, build a new socialist countryside, in recent years our country has labeled the walnut industry as a major project. As national characteristic agriculture and forestry economic industry, at present, the walnut planting scale, yield and output value of forestry economic industry has reached the advanced level and the leading position in the world. With the development of walnut production and market demand constantly increasing, walnut shell crushing and kernel fetching process in deep processing also has become increasingly prominent issue in scientific research and production.Traditional manual shell crushing and kernel fetching process has a serious impact on the production efficiency and product quality. Therefore the innovative design of a automatic mechanical walnut shell crushing and kernel fetching equipment which was popularized all over the country to solve the current situation of walnut processing backwardness is significant. At present, the existent walnut shell breaking devices mainly adopted the rigid element which existed problems of low shell-cracking rate and kernel-exposing rate. Most walnut shellers which were poor adaptability for different varieties of walnuts blindly pursue improving hulling rate which lead to high walnut kernel-breaking rate and high loss rate. Using flexible components and design a reasonable mechanism could effectively improve the shell-cracking rate and kernel-exposing rate, reduce damage of walnut and improve the kernel-unbroken rate.Walnut shearing-extrusion flexible shell crushing, kernel taking and shell-kernel separating device is used in this research witch focus on the structure design and mechanism analysis of flexible belt shearing-extrusion and hulling system, especially experimental analysis and research on this system. The specific contents are as follows:1. Aiming at problems in the production and processing of walnut shell-crushing and kernel-taking process, analyzing the present existing method, the method obtains the ideal mechanical device; In view of different mechanical shell-breaking method,summarized the domestic and foreign walnut shell-breaking and hulling kernel-takingmachinery equipments research present situation. Research status on mechanical characteristics of nuts shell crushing process at home and abroad are introduced and analyzed.2. The composition structure of walnut shell crushing, kernel taking and shell-kernel separating device is introduced and composition structures of flexible belt shearing-extrusion on shell crushing and hulling systemⅠ, kernel-taking by hammering of flexible blade system Ⅱ, walnut shell-kernel two-way separation in rotary drum under the action of coupling between air and flexible helical blade system Ⅲ are detailed introduced. Also their working process and the principle are analyzed.A new type of walnut classification equipment is designed and the respective components in three systems in the device are also improved designed.3. The geometric and physical parameters of walnut are explored and the three dimensions and the thickness of the walnut shell are measured; Mechanism of walnut shell crushing and hulling are explored and mechanical properties of walnut shell is analyzed. The elastic mechanics theory is used to calculate the critical force of unstability in different shell location; The thin shell theory is used to explore the rupture source of walnut shell and work out the critical force of crack generation and shell crush in different shell location; The fracture mechanics is used to analyze the conditions of crack propagation and calculate the critical force of crack generation; Based on the walnut shell-broken device, Conditions for walnut entering into the extrusion space,extrusion angle, rotation angle and stress in shell-broken zone and hulling zone are respective analyzed.4. Based on walnut shearing-extrusion flexible shell crushing, kernel taking and shell-kernel separating device, walnut shell-crushing mechanics properties and effects are respective analyzed. Impacts on shell-crushing mechanics properties and effects are respective analyzed by single factor experiment method. Then impacts on the order of shell-crushing force is calculated by the multi-factor orthogonal experiments and a set of optimal parameters about ideal shell-broken rate and kernel-unbroken rate are confirmed.5. Based on walnut shearing-extrusion flexible shell crushing, kernel taking andshell-kernel separating device, walnut shell-hulling effects are analyzed. Impacts on shell-hulling effects are respective analyzed by single factor experiment method. A set of optimal parameters about ideal hulling rate and kernel-unbroken rate are confirmed.