Structure Design And System Simulation Research Of Load Limiting Type Pneumatic Hoist

With the advancement of technologies,pneumatic technology has been widely applied.and new types of pneumatic tools have gradually entered the market.of which Pneumatic hoist has a strong market's competitive,It is widely used in the inflammable and explosive dangerous environment,such as military,petroleum and chemical industry.Gradually replaced the existing hand hoist and electric hoist.But according to the pneumatic hoist research status analyzing research at home and abroad.lt is found that many problems exist in the domestic pneumatic hoist,such as inadequate shell load capacity,poor braking performance,large motor noise and unlimited load limit protection,which has a great impact on its safety in production and popularization.In allusion to these problems,this paper first according to the subject of the requirements of the technical indicators of pneumatic hoist.the overall design of the mechanical structure,analyzes the influence of load capacity and the factors of improve the speed,based on the working principle and structure characteristics of pneumatic motor,and establish its mathematical model and torque balance equations of motor internal pressure changes,and the motion simulation analysis was carried out.and then improve the stability of motor by changing its structure parameters by simulation results.Further more,brake is also as key components of pneumatic hoist in safety production,Not only the reasonable design of the main structure,but also the force situation of the spring should be analyzed and optimized.The vibration equation of spring is obtained to improve the braking effect of pneumatic hoist.Secondly,by using AN SYS Workbench analysis software,and pneumatic hoist shell has been structural static analysis,although the local stress concentration,but the shell is under the rated load,the maximum strain value 0.038mm is less than the elastic strain of the shell material,Assure the pneumatic hoist shell on the strength and stiffness requirements;Through the transient analysis of the brake,It is concluded that the effect of friction disk wear on braking performance under the condition of sudden braking outside,and the braking performance of the brake can be further improved according to the simulation results.Through modal analysis of the pneumatic motor,Obtain the analysis frequency list and a modal cloud chart,According to the obvious modal discovery of frequency variation:The vibration of the pneumatic motor at 539.78HZ and 2404.3HZ is the most intense,highest noise,Should reduce the motor spindle circular section radius,Reducing the influence of the motor on the working environment.Finally,Using the AMESim software of modeling and simulation platform to build a AMESim aerodynamic simulation model for the designed pneumatic system.Through the AMESim software,the brake pressure,the response speed and the torque of the motor spindle are analyzed in the pneumatic system.and the braking force can be up to 3 times of the load in 0.05s.Ensure the system can quickly achieve the effect of braking in a safety time.And the simulation also shows that when the load exceeds the rated load of the motor torque will be reduced to zero,Achieve to limit the load protection purposes,At the same time,the reliability and stability of the pneumatic system is further demonstrated.