Design Of The Rotary Lift Mechanism Of A Commercial Vehicle Transportation Semi-Trailer

With the continuous development of modern logistics, its influence on the national economy development, and in competition is increasingly pronounced. These passenger cars, as a mode of transport, in improving the road utilization rate, reduce energy consumption and so on to perform well and bring high economic benefits. As a new special vehicle, the commercial vehicle transportation semi-trailer is a transition in that direction. Therefore, how to implement a safety, reliability and stable performance and high performance in compressive strength of the semi-trailer track has become the research emphasis of the current industry.Based on an actual engineering project, the subject of this essay is to carry on the design for the forward lift mechanism on a commercial transport semi-trailer, to design the semi-trailer gooseneck into a type of rotary lift mechanism, to utilize the change of the rotary lift plate angle to make sure the angle between the lifting plate and the horizontal ground is smaller than the angle of the departing vehicle, therefore to ensure the semi-trailer truck with the loading mechanism is not over-sized. First of all, this essay analyzed the compared the structural characteristics of this type of vehicle both at home and abroad, using a 3D model generated with UG software. The structure is mainly composed of gooseneck, main frame, rotary lift plate and the traction device consisting of hydraulic cylinder, wire rope linkage and other components, according to the actual demand of the mechanism in different operating mode of motion state. And then, modal analysis was carried out on the lifting mechanism to get the first six order natural frequency and modal characteristics. Results show that the agency does not produce resonance, laying the foundation for the further study for institutional dynamics. Next, to increase working stability and reliability of the rotary lift mechanism, and improve the mechanical state of the lifting mechanism, this paper aims to reduce the oil cylinder force as the optimization goal, using Matlab software to simulate optimization, optimization point and the curve of the optimization goal, then analyze and select the best scheme. The optimized oil cylinder force decreased by 8.92% compared with the initial value. Finally, based on the theoretical prototype which has been modified and tested, the feasibility of design has been verified.