Research On The Hydraulic Lifting Mechanism System Of Moving Sieve Jigger

Gangue proportion and ash increase sharply as the popularity and promotion of mechanization method coal mining. Lead to the nature of coal drops. It goes against environmental protection used directly. Because of the simple preparation,low running cost,water and energy saving,high separating accuracy,large fraction width and large treatment capacity. Hydraulic moving sieve jigger has developed into one of the most economical and suitable technique to remove gangue. In the research it found that the layering of coal is related to the quality of separation. It is necessary to research the key factors which effect coal delaminating from coal dressing theory, and aims at these key factors, to analysis the hydraulic system and essential part. At the same time, considered mechanical shock and so on insufficiencies are existed in the equipment. Transform has been done on the original hydraulic system and optimize the hydraulic system.Firstly, the paper researches the effecting factors which affected separation from the dressing theory. It includes the gangue's delaminating and discharging. The primary factor which influences delamination of coal and gangue is the law of motion of material going along with sieves highly and lowly. Through the comparative studies between the mechanical driving and the hydraulic driving sieve jigger, discovered that the beginning acceleration of sieves is bigger than the gangue's when the sieves drop. The materials separated from sieves completely and have enough time and spatial to delaminate. The discharge speed of gangue related to the rotate speed of discharging wheel. The rotational speed is decided with the promotion of pressure value of cylinder and referenced value SP4.The paper propose the method of calculating the SP4 value and writing VB procedure. It's facilitative for the theoretical calculation of SP4 value when sieve jigger in different working condition. It save time for the debugging and raises the production efficiency.Secondly, hydraulic system digital simulation method based on the power bond graph and MATLAB used to research the dynamic characteristic of the hydraulic system and essential part. Simulate the process of hydraulic system by changing the simulation parameters. Analysis the result and draws the conclusion. It has reference significance for the optimization design and the transformation of sieve jigger. The bond graph model has be built for the hydraulic system,proportion throttle valve,host pump and cylinder in the paper and used MATLAB to simulate it,analysed the response rapidity and stability of the hydraulic system to found out the factors which influence the law of motion of the sieve. Optimized the system based on the analysis result proved that the dynamic characteristic of the lifting mechanism can satisfied the request of separation. Considered that mechanical shock exist when the sieve drop down. It put forward that to use the proportion throttle valve to adjust the dropping speed on condition that it didn't affect the lamination. Because of short time, the pure hydraulic brake will cause hydraulic shock,oil overheated,valve rapid wear. Therefore,Using throttling to modulate velocity and the spring damping system to brake the way. In this way it can reduce the mechanical and hydraulic shock simultaneously.Finally, the paper designed the measurement and control system for the lifting mechanism. Mainly studied the magnetostriction position sensor used to detect the piston travel of lifting cylinder.The speed and the acceleration of cylinder also can be detected by design differentiating circuit. For this, it can real-time monitor the law of motion of sieve and enable the separation effect to achieve superiorly.