Design And Simulation Analysis Of Doffer Extubation Device With Self-adaptive Function

With the development of science and technology,the application of automation equipment in the textile industry is becoming more and more extensive,and manual doffing will gradually be replaced by automatic doffing.In recent years,major manufacturers have successively introduced automatic doffing machines,but these doffing machines still have some problems when working,such as poor doffing stability,inability to adapt to spindle installation errors,and serious damage to the yarn during doffing,which have brought certain troubles to the spinning work.In view of the problems of the automatic doffing machine,this paper designs a new doffing machine equipped with a pipe-drawing device that can automatically adapt to the installation error of the spindle.The pipe pulling device uses a dual rocker mechanism to simulate the trajectory of a human hand pulling a pipe,a parallelogram mechanism to simulate a hand's twisting action to achieve pre-loosening,and a floating connecting plate to automatically adapt to the installation error of the spindle within a certain range.This new type of doffing machine is suitable for spinning frames with a spindle pitch of 70 mm.It can draw 6 bobbins at the same time,and the drawing cycle is 3 seconds.The main research work and conclusions of this paper are as follows:(1)The scheme design and structural design of each part of the automatic doffing machine is introduced,the main part is the design of the actuator of the extubation device and the design of the adaptive clamping device;the driving cylinder of the extubation device is preliminarily selected;the paper uses Solid Works to model and assemble each part,and describe the overall working process of the doffing machine.(2)The expected trajectory of the extubation mechanism is designed by referring to the trajectory of manual extubation.The optimization method is used to optimize the parameters of the extubation mechanism according to the expected trajectory,and the mechanical parameters meeting the expected trajectory and design requirements are obtained.Using ADAMS to simulate the trajectory of the extubation mechanism after parameter optimization,and the obtained trajectory curve meets the requirements.(3)The dynamic simulation of the extubation device and the lifting device is carried out by ADAMS,so as to obtain the dynamic parameters.According to the difference of spindle installation,the pipe drawing process can be divided into accurate spindle installation and spindle installation error.The simulation results show that,regardless of the spindle installation error,the maximum driving force of the main cylinder and the resetting cylinder are basically unchanged.The maximum driving force of the main cylinder is 1189.46 N,and the maximum driving force of the resetting cylinder is 26.70 N.The maximum driving force of the clamping cylinder is 726.94 N when the left material clamp is shifted to the right and the right material clamp is shifted to the left;the maximum driving force of the propelling cylinder is 23.40 N when the clamps on both sides of the holder are deflected to the left.The driving force results obtained by the simulation verify that the primary cylinders meet the requirements;there are certain differences in the forces between the components in the two cases,and the calculation results have laid the necessary foundation for the finite element analysis.(4)Combined with the results of dynamic simulation,the statics analysis is performed on key components by ANSYS Workbench.The analysis results show that the maximum equivalent stress and maximum deformation of other parts except the sliding shaft pin under the lifting device are less than the design requirements.Reasonably increase the shaft diameter of the sliding shaft pin under the lifting device and reanalyze it,and the result meets the design requirements.