Research On Key Technology Of Hydraulic Retarder For Construction Vehicle

With the rapid growth of China’s highway grade and mileage,road transport has become an important transport route,and thus the safety requirements for the operation of transport vehicles are increasingly high.Large vehicles running long distances have greater safety risks,so the braking safety of large vehicles have special requirements,except the original vehicle wheel-side brakes brake also requires an increase in the corresponding auxiliary brake,to meet the large vehicles in the long downhill driving safety brake.For the vehicle auxiliary braking needs,the auto parts suppliers developed a hydraulic retarder and eddy current retarder and other devices.Certain limitations can be found after these two kinds of auxiliary braking equipment been analyzed.And the defects can be eliminated by the development of hydraulic technology.Based on this,the research of hydraulic retarder brake is performed in the paper.Firstly,the hydraulic system and retardation scheme of the hydraulic retarder is designed according to the vehicle long downhill retardation conditions and the vehicle braking requirements.At the same time,under the condition of the existing target vehicle parameters,the hydraulic retarder components are calculated for the long downhill retardation braking condition of the target vehicle at a slope of 6%;and the main components of the system are selected by combining the relevant product samples and technical manuals.Secondly,in order to make the hydraulic retarder to be able to better cooperate with the vehicle’s running brake,better play the role of the hydraulic retarder and vehicle running brake,and improve the braking efficiency.In this paper,based on ECE regulations and China’s relevant standards and regulations,the braking force of the target vehicle before and after the retrofitting of hydraulic retarder is analyzed.Finally,the control strategy of the hydraulic retarder when retarding and the braking control strategy under low intensity braking are determined.Finally,the components,system and vehicle power system of the hydraulic retarder are modeled and simulated by AMESim software.At first,the simulation analysis is carried out separately for the continuous braking condition and transient braking condition of the hydraulic retarder.The simulation results show that the hydraulic retarder can provide the braking torque quickly and stably.Then the thermal balance simulation of the hydraulic retarder system is carried out.The results show that the maximum temperature of the hydraulic retarder under the limit working condition meet the working requirements of the system.At last,the combing simulation analysis of the hydraulic retarder and the vehicle power system are carried out.The simulation results show that the hydraulic retarder can meet the demand of slow braking of the vehicle on long downhill slopes and low braking intensity of the vehicle.The use of the brakes of the vehicle is been reduced and therefore the service life and driving safety are ensured...