Structure Optimization Design Of Automatic Tea Rolling Device

Tea is an important agricultural economic crop in China,but the current tea processing equipment has a low level of automation and high labor costs.Rolling is a very important process in the tea making process,and the rolling pressure directly affects the quality of tea.At present,the rolling pressure is mainly applied by the tea maker based on experience.The pressure applied for each batch is difficult to accurately control,which leads to unstable quality of processed tea and seriously affects the quality of tea.Therefore,in this paper,based on the existing 6CR-55 single-column kneading machine,the structure of the pressing device and the discharging device were improved and optimized,to realize the automatic pressure and automatic discharge of the rolling,so as to improve the stability of tea quality and reduce labor intensity.The main research contents are as follows:(1)The structure design of the automatic pressurizing device of the tea rolling machine.The automatic pressurizing device was composed of connecting flange,thrust bearing,backing plate,pressure sensor,kneading shaft and spring.By analyzing analyzing the stress distribution in the process of the tea rolling and dynamics simulation of rolling axis cover,the pressure sensor and the corresponding installation structure were designed.And based on the simulation results,the DYLF-102 spoke-type pressure sensor was selected,and the thrust bearing structure was selected to ensure that the squeezing force generated by the fresh tea leaves on the kneading barrel lid was transmitted along the axis of the kneading shaft,so that the pressure value measured by the pressure sensor was basically the squeezing force generated by the fresh tea leaf on the kneading barrel lid.In order to realize the automatic work of the tea rolling machine,the lid of the rolling machine was automatically opened and closed controlled by a motor,the limit position opening and closing of the lid of the rolling machine was very important.In order to make better use of the existing structure of the kneading machine,a proximity switch was installed on the cross arm beam for control.(2)The structure design and optimization of the automatic unloading device of the tea rolling machine.On the basis of the original structure of the manual unloading structure of the rolling machine,a crank shaper mechanism was proposed to realize the opening and closing of the unloading chassis.And the switch structure of the discharge tray controlled by the handle was transformed and controlled by a motor.The structure of the automatic unloading device was mainly composed of a stepping motor,a discharge chassis shaft,a crank,a guide rod,and a slider.The parameterized design and optimization analysis of the crank slider were carried out by ADAMS.The results showed that X-axis DV＿Xc of the connection point C between slider and guide rod has the greatest influence on the torque,while Y-axis DV＿Ya of the connection point A between crank and motor)and Y-axis DV＿Yc of the connection point C between slider and guide rod have almost no influence on the torque.the motor drives the maximum crank The torque value was optimized from the initial 22961.3N.mm to 14528.8N.mm,which is a reduction of 36.7%;the installation position of the crank was optimized from the initial-240 mm to-99.81 mm,which was a reduction of 58.4%,and the optimization effect was significant.In the process of kneading,the brake of the motor was used to lock the unloading chassis.Install proximity switches on the motor mounting frame and under the kneading disc to control the opening and closing positions of the unloading chassis.(3)Prototype performance test.The automatic pressurizing device and the automatic unloading device were trial-produced and assembled in the 6CR-55single-column rolling and twisting machine device.Based on the STM32 single-chip microcomputer,the tea rolling and twisting machine control system was developed to realize the automatic pressure,automatic rolling and automatic rolling of the tea rolling process.The test results of the prototype machine showed that the pressure sensor could accurately detect the rolling pressure during the rolling process,and the automatic pressurizing device could automatically pressurize the tea leaves according to the pressure value set by the system.After the rolling was completed,the tea leaves were automatically discharged and the entire rolling process was completed automatically.