Research And Design Of Pneumatic Extrusion Walnut Shell-Breaking Machine

Walnut is rich in nutrients and has great market potential in China.In recent years,with the support of national policies,walnut production in China has been increasing year by year,showing a good momentum of vigorous development.However,the development of walnut deep processing industry in China is relatively backward,especially the mechanized walnut shell-breaking technology,which basically depends on manual treatment,resulting in high cost of walnut shell-breaking,which has become a bottleneck problem restricting the industrial application of walnut.Therefore,it is urgent to develop mechanized walnut shell-breaking technology.Based on the analysis of the current situation of walnut shell-breaking technology and the research of related literature at home and abroad,a new walnut shell-breaking machine was developed in this paper.Firstly,the physical properties of walnut and mechanical properties of walnut shell breaking were researched.Using "Zhipin" brand thin-shelled walnut produced by Xingtai Production Base of Hebei Greenlei Agriculture and Forestry Technology Co.,Ltd.as the research object,the physical parameters such as water content,three-dimensional size distribution and shell thickness of walnut were measured,and the influence factors of walnut shell breaking were carried out.The results showed that the variation degree of walnut three-dimensional diameter was small and the difference of shell thickness in different parts is obvious.The four-point mold with 60° angle has the best shell-breaking effect when it is used to break the shell longitudinally.The maximum force required for walnut shell cracking is 579.65N.Secondly,the theoretical research on the mechanical principle of walnut shell breaking and the design of the shell breaker structure were carried out.In the beginning,the principle,advantages and disadvantages of common nut shell breaking methods were studied.The working principle of pneumatic extrusion shell breaking was determined according to the physical property of the measured walnut.Then,the overall structure,actuator and action trajectory of the shell breaker were determined.The feeding mechanism,shell breaking mechanism and unloading device were designed.The parameters and selection of the main pneumatic components used in the pneumatic system were carried out.The control mode and process of the electronic control system were selected and designed.Finally,the three-dimensional virtual model was established,and the drawing design was completedThirdly,experiments on shell-breaking of walnut were carried out.The test bench was manufactured and debugged,and then the shell-breaking effect experiment was carried out.The results showed that the walnut shell-breaking machine developed in this paper,using"Zhipin" brand thin-shelled walnut with 9.84%moisture content as raw material,can reach 86.87%of the first shell-breaking rate,83.54%of the high-dew-kernels rate,53.65%of the kernels yield rate and 94 kg/h of the processing efficiency.The research results can provide technical and equipment support for walnut shell-breaking processing.