Research On Knotting Technology And System Design Of Automatic Binding Knotting Machine

In the agricultural and sideline food processing industry,the use of woven bags for packaging is one of the most common marketing and transportation methods of agricultural and sideline products such as broccoli and green beans.However,due to the need to use rope in line with food safety requirements for food packaging,most of the existing knotting machines can not be applied to the bundling and packaging of agricultural and sideline food.As a result,inefficient and labor-intensive manual packing is still the main method.Aiming at the problems of low efficiency and high labor intensity of manual knotting in agricultural and sideline food industry,a special automatic tying machine is designed in this paper.The machine uses rope to tie double-knot,which is used to tie flexible packaging bags such as woven bags.Specific research contents are as follows:(1)Investigate user needs,determine research and development objectives,review literature,analyze the research and development status of knotting technology and equipment at home and abroad,and draw existing research and development experience for the design of automatic tying machine.(2)Based on the analysis of the mechanical knotting process of double-knot,the manual knotting process of double knotting is divided into two rope clamping,rope picking,rotation,rope lashing,fastening and other processes.According to the knotting process,design the way of mechanization operation,formulate the whole machine design scheme,combined with the motion state of the rope to design and calculate the key structure.The designed automatic bundling machine is divided into bunching station and knotting station.The mechanized bundling and knotting process is divided into bunching,knotting,sleeve,tying,rope breaking,rope renewing and other procedures.The machine can complete all the above procedures in one operation.(3)The 3D modeling software UG was used to establish the structure of the whole machine,and the kinematic simulation of the key structure was carried out based on the 3D model with the software ADAMS.By comparing the position relationship between key points and reference points in the process of movement,it is verified that the machine can successfully lashing rope and bunching mouth in the process of operation.The movement of each mechanism conforms to the initial design requirements and can realize automatic binding and knotting.(4)The design of the control system is divided into two parts:control hardware selection and control program preparation.Choose the domestic H842.12 bus PAC controller as the control core;According to the knotting process and the design of mechanized operation mode,the servo motor with high control precision is selected as the power source of rotating motion,the pneumatic claw and pneumatic slide with sensitive action and low cost are used as the executive parts of rope clamping and transportation device,and the electric slide is selected as the executive parts of the rope sleeve device with high position accuracy requirements.In order to boost the development of domestic industrial control technology,the HPAC software compiled control program developed by Huazhong Numerical Control team is used.The SFC language with strong structure is used as the main program,which has good expansibility and readability.In order to conform to the trend of intelligent development,a good man-machine interaction interface is designed for the automatic binding and tying machine,which can display the real-time state of each part of the system during debugging and running,and can give control instructions to the machine through the interface,which improves the efficiency of detection and operation.(5)The bundling machine prototype was made according to the design scheme,and the knotting success rate and knotting efficiency of the prototype were tested.The test results showed that the knotting success rate of the bundling machine was 92%,and the knotting efficiency was 28.2 seconds/piece,which met the requirements of the expected design objectives.The operation effect of the control system was tested.The interactive operation between the human-computer interaction interface and the machine can be normally fed back to the display interface,and the instruction transmission is accurate.The knotting effect is better in the automatic mode,and the control is accurate in the manual mode.