Development Of Automatic Bagging Device For Lentinus Edodes Stick

Lentinus edodes production ranks first in the total production of edible fungi in China,while stick cultivation is the main cultivation method of Lentinus edodes in China.The production of mushroom sticks requires manual wrapping of water-retaining film and bags on the discharging barrel of mushroom stick automatic loading machine.The bagging work is intensive and has potential safety hazards.With the problem of insufficient agricultural labor force becoming more and more serious and the rising labor cost,it is urgent to realize the automation of mushroom stick bagging process.Therefore,the research on automatic bagging equipment of mushroom sticks has important scientific research value and practical significance.In order to realize the automatic bagging of mushroom sticks,the following four aspects were studied in this paper.(1)Physical characteristics of water-retaining film and bacterial bags.The purpose of this study is to provide theoretical basis for the scheme selection and design of automatic bagging device for mushroom sticks.The size parameters of water-retaining film and bacterial bags were measured and their structural differences were analyzed through field investigation.Using universal testing machine,vacuum pressure sensor and other equipment,the air absorption characteristics of different diameter vacuum suction cups to water-retaining film and bacterial bags were studied.It was concluded that the vacuum suction cup with diameter of 10 mm had the best air absorption effect on water-retaining film and bacterial bags.According to the GBT1040.3-2006 standard for testing the tensile properties of plastic,the tensile properties of water-retaining film and bacterial bags were tested and the stress-strain curves were obtained,which provided the basis for the design.(2)The general scheme of automatic bagging device for mushroom sticks was determined.The technology of artificial bagging was analyzed,and the function and performance requirements of automatic bagging device for mushroom sticks were put forward.According to the manual bagging technology,the automatic bagging device of mushroom stick needs to complete four working processes: bagging,opening,round supporting and bagging.The workflow schemes are selected according to the functional and performance requirements.The transmission scheme of bag-taking scheme chooses synchronous belt drive and ropewheel drive,air-suction bag-taking scheme and bag-changing scheme of mobile bag-box,opening and supporting scheme chooses piecewise opening round-supporting scheme,and bagging scheme chooses pneumatic scheme to drive.(3)Research on key components and design of control system.The guide structure of the supporting mechanism is designed and studied.The basic dimension parameters of the guiding structure are determined according to the size structure of the water-retaining film,the bacterial bag and the discharging cylinder.Then the theoretical calculation of the tensile properties of the water-retaining film and the bacterial bag is carried out.Static analysis verifies that the water-retaining film,the bacterial bag and the supporting plate will not be damaged or broken during the supporting process.Finally,in order to ensure the bagging process.Bacterial bags and water-retaining film will not slip.The influencing factors of friction between water-retaining film and bacterial bags and guide structure are analyzed and the orthogonal test of multiple linear regression is carried out.The distance between grooves on the surface of supporting circular bracket is 0.3 mm and the depth of grooves is 1.84 mm.According to the automatic bagging workflow,the selection of stepper motor and sensor and the design of detection system are completed,and the STM32 single chip computer is selected as the controller,and the flow chart of the control system is finally completed.(4)prototype manufacture and test.In order to verify the effect of bagging,a test prototype was developed.The parameters of the opening mechanism are optimized by multifactor orthogonal test.The optimal combination is: the number of sucker rows is 3,the number of sucker rows is 3,the cylinder speed is 0.3 m/s,and the sucker installation position is 10 mm away from the edge of the bacterial bag.The validation test of the whole machine shows that the success rates of water-retaining film and bacterial bag are 94% and 100%,respectively,the success rates of opening 94% and 100%,and the success rates of supporting round bag are 100% and 92%.The success rate of bagging is 92%.The bagging of one water-retaining film and one bacterial bag can be completed in turn every 20 seconds.