Study On Separation And Transport Device For Remnant Plastic Film

This paper describes the background and significance of the research topic, introduced the source of the research topic and the contents of the research. This work used fuzzy optimization method and theory, multi-body kinematics and dynamics and virtual prototyping technology, method and theory to carry out machine analysis, modeling and simulation. Experimental tests show that the theoretical model is accurate and design results are reasonable.Due to the lack of appropriate machinery and labor, large quantity of remnant plastic film can not be recycled thereby left as residues on arable land, causing serious pollution to the soil and ecological environment. Depending on the manual use of hand picking of remnant plastic film is labor intensive, work efficiency is low and recovery rate is low, therefore mechanical cleaning of farmland remnant plastic film is the most effective way possible. Based on this, the study of farmland remnant plastic film pollution handling technology and equipment for agricultural production is one of the most important factors for this present study.As a result of the remnant plastic film contamination of the soil and the environment, foreign countries use less plastic film. The plastic film in use in Japan, the United States and some European countries are generally thicker (0.02 - 0.05mm), the strength is large thereby using roller-type plastic film recycling machine. The main locally developed machineries for mechanical cleaning and recovery of remnant plastic film are film–tearing machine during seedling and spring-tooth film rake after harvest. According to the main working mechanism, plastic film recovery machinery can be divided into spring-tooth, telescopic rake,fixed tilt-tooth, , and a variety of pneumatic equipment. At present in China plastic films (0.006-0.008mm) are in use and remnant plastic films have strong adhesion on the working part, tying and hanging on the teeth, a key technical problem yet to be resolved. During the use of pneumatic method to recover remnant plastic film, it is difficult for the air to separate out plastic films mixed within the soil. Therefore, this study developed plastic films loosening shovel and rake machine structure, zigzag scraper with other new model for remnant plastic film separation and transportation devices. The parts structural principles and trajectory movement design prevented the remnant plastic film from winding around the working parts thereby solving the technical problems of winding around the working parts. These devices provided key techniques and theories for studies on farmland remnant plastic film pollution control devices, research and development. For field cleaning and land preparation operations overall design, Pro / Engineer software was used to achieve movement entity model, the test assembly is accurate. Tests showed that the design results are correct, reasonable and working performance is reliable.Machine transmission pressure angle, remnant plastic film recovery rate, soil resistance, remnant plastic film tensile strength, machinery mechanical reliability and others have fuzzy attributes and fuzzy optimization method and theory was used for design. The design is practical, economical and satisfactory mechanically. Using multi-body system dynamics modeling basic theory, Pro / E and ADAMS software functions, kinematics and dynamic forces analysis, modeling, simulation, the design was carried out. This improved design efficiency and reduced prototype manufacturing costs. Fuzzy optimal design is based on fuzzy mathematics and mechanical design optimization theory to develop new design methods and theories for use in the field of agricultural machinery design. This can solve many traditional design and precision design insurmountable problems. The three basic elements of fuzzy optimal design are objective function, constraint function and design variables. In engineering design these elements are often "vague", therefore using fuzzy method to solving the problem, can be more in line with the actual engineering design optimization results. The plastic film loosening shovel main function is to collect remnant plastic film from the soil. During operation, it will go down up to 120mm below arable land surface to lift up remnant plastic film, crop residues, soil and other mixed up materials. Some soil is separated through the holes on the shovel and most materials are transported by the scraper conveyor to the back separating sieve . The loosening shovel working speed, soil penetration angle and soil characteristics have enormous impact on working resistance and soil conditions. By analyzing the structure and principle of film loosening shovel working resistance, established film loosening shovel fuzzy evaluation model. In order to optimize the structural parameters and operating parameters, a large number of tests were carried out and concluded that loosening shovel panel best hole size and best working angle areφ66 and 35°respectively.Remnant plastic film separating sieve device are equipped to clean the field and prepare the soil. During operation, this device will separate remnant plastic film and crop residues from soil then conveyed them to the film box. Through the analysis of separating sieve device structure movement and the plastic film materials on the separating sieve surface movement pattern, a mathematical model was developed for remnant plastic film separating sieve movement. Pro / Engineer software was used to establish remnant plastic film separating sieve 3D model for movement simulation. Through analysis of the simulation experiments and optimizing the separating sieve structural parameters and motion parameters, the rate of remnant plastic film separation rate effectively increased and the separating sieve reciprocating inertial force caused by the vibration decreased. Tests showed that the vibration frequency for remnant plastic film separating sieve has great impact on the rate of separation. At the flywheel speed of 175r/min, separating sieve has better separation ability and the operation is more stable. Tests show that the design is reasonable and the remnant plastic film separation performance is reliable.Remnant plastic film rake link pole structure is spring-tooth of four-links pole support, spring-tooth is fixed on the links mechanism pole to transport and collect remnant plastic film. Analyzing the spring tooth movement and with the aim of obtaining spring-tooth optimal trajectories, links mechanism structural optimized mathematical design model was established. Fuzzy optimization principles and methods was used for the constraint function allowable pressure angle, spring tooth trajectory maximum height, avoiding spring tooth reverse film allowable angle with fuzzy treatment, established fuzzy optimization model design and use optimal level set to solve fuzzy optimization problem. With known crank mechanism, machine frame and spring-tooth structure size, design calculation revealed that optimal links mechanism pole and optimal rocker links mechanism pole size of 0.39m and 0.385m which is less than the original size by 13.3% and 8.3% respectively. Fuzzy optimal links mechanism design achieved the expected trajectory motion, the operation of spring tooth, its functional position and angle met working requirements effectively preventing remnant plastic film winding and clogging.Zigzag scraper for remnant plastic film, crop residue and soil transportation devices structure and principles were studied. With scraper set minimum operational energy consumption taken as the objective function, established optimal mathematical design model using optimization calculation to determine scraper structural size, configuration space, the working speed and the working angle for optimal design results. According to the multi-body system modeling theory and using Cartesian system method developed the device system kinematics and dynamic mathematical model with the use of ADAMS software simulation, carried out in-depth analysis of the system movement and kinetic characteristics. From experiments, it was discovered that when the scraper set and shovel locations are not properly arranged, it is easy for loosening shovel soil have sharp increase in working resistance which at serious times lead to operation breakdown. Therefore, through trials confirmed that the best scraper set location to loosening shovel is c = 300mm. Test results show that optimal design result is reasonable, under certain operating speed can completely meet the design requirements and in the testing process no remnant plastic film is wrapped around the scrapper. To conduct more in-depth studies on farmland remnant plastic film pollution control key technology and equipment, comprehensive use of fuzzy design optimization, neural network, virtual prototyping technology, intelligent design and digital design methodologies and theories are needed. Finally, to conclude the present study results and innovation, areas for further research were highlighted.